Diabetic kidney disease (DKD) is a major complication of diabetes mellitus, characterized by podocyte injury and lipid accumulation, which contribute to high morbidity and mortality. Current treatments primarily alleviate symptoms, underscoring the need for targeted therapies to address the underlying mechanisms of DKD progression. This study explores the protective effects of dapagliflozin (DAPA), a selective sodium-glucose cotransporter 2 (SGLT2) inhibitor, on podocyte lipotoxicity and its regulatory role in the estrogen-related receptor alpha (ERRα)-acyl-CoA oxidase 1 (ACOX1) axis. Using db/db mice and streptozotocin-induced DKD models, we demonstrate that DAPA significantly reduces the urinary albumin-to-creatinine ratio (ACR) and improves renal pathology by alleviating glomerular hypertrophy, mesangial matrix expansion, and podocyte foot process effacement. DAPA also decreases triglyceride and free fatty acid accumulation in glomeruli, as evidenced by Oil Red O and BODIPY staining. Mechanistically, DAPA upregulates ERRα and ACOX1 expression in podocytes, enhancing fatty acid oxidation (FAO) and mitigating lipidtoxicity. Loss of ERRα exacerbates lipid-induced podocyte injury, while ERRα overexpression confers protective effects. These findings highlight DAPA's renoprotective effects via modulation of the ERRα-ACOX1 axis, suggesting that targeting ERRα could be a promising therapeutic strategy for DKD.

Our review summarizes and evaluates the current state of knowledge on lipid metabolism in relation to the pathomechanisms of kidney disease with a focus on common pediatric kidney diseases. In addition, we discuss how nutrition in early childhood can alter kidney development and permanently shape kidney lipid and protein metabolism, which in turn affects kidney health and disease throughout life. Comprehensive integrated lipidomics and proteomics network analyses are becoming increasingly available and offer exciting new insights into metabolic signatures. Lipid accumulation, lipid peroxidation, oxidative stress, and dysregulated pro-inflammatory lipid mediator signaling have been identified as important mechanisms influencing the progression of minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, diabetic kidney disease, and acute kidney injury. We outline key features of metabolic homeostasis and lipid metabolic physiology in renal cells and discuss pathophysiological aspects in the pediatric context. On the one hand, special vulnerabilities such as reduced antioxidant capacity in neonates must be considered. On the other hand, there is a unique window of opportunity during kidney development, as nutrition in early life influences the composition of cellular phospholipid membranes in the growing kidney and thus affects local signaling pathways far beyond the growth phase.

Tubulointerstitial fibrosis (TIF), a critical pathological hallmark in progressive chronic kidney disease (CKD), may be potentiated by renal lipid metabolism dysregulation and ectopic lipid deposition, though these processes likely exhibit bidirectional interactions with fibrotic progression Lipophagy is a type of selective autophagy that specifically recognizes lipid droplets and is accountable for lipid stability and metabolism. It serves as a link between lipid metabolism and autophagy. It was found that a positive correlation between elevated LARS1 expression and the severity of renal interstitial fibrosis in CKD patients. In Lars1+/- mice, we observed that the absence of LARS1 significantly reduced lipid deposition and TIF. Mechanistically, stimulation of HK-2 cells with TGF-β1 resulted in LARS1-mediated activation of mTORC1 and suppression of lipophagy, consequently leading to increased lipid accumulation and epithelial mesenchymal transition (EMT) through a defined mechanistic pathway. Collectively, our studies demonstrate that LARS1 plays a pivotal role in renal fibrosis at least in part by inhibiting lipophagy, suggesting that targeting LARS1 may represent a novel therapeutic strategy for patients with CKD.

To explore the influence of the serum total bilirubin to total cholesterol (TBIL/TC) ratio on the progression of chronic kidney disease (CKD) in people with type 2 diabetes.

The present retrospective discovery cohort investigated 4282 patients. The exposure was baseline TBIL/TC ratio. The outcome was the first time to progressing CKD, defined by a drop in the estimated glomerular filtration rate (eGFR) category, along with a reduction in eGFR of at least 25% compared to the baseline value. Hazard ratios (HRs) for CKD progression were evaluated based on the Cox proportional hazards approach. Dose-response relationships were conducted using Restricted Cubic Splines (RCS). Additionally, 758 patients were enrolled as an independent validation cohort.

During a median observation period of 2.4 years (interquartile range 1.3-3.8 years) within the discovery cohort, 522 individuals showed progression in CKD. The analysis revealed a negative association between the TBIL/TC ratio and the risk of CKD progression, with an adjusted HR of 0.17 and a 95% CI ranging from 0.07 to 0.41. After adjusting for confounding variables, the HRs for the second, third, and fourth quartiles of the TBIL/TC ratio were recorded at 0.61 (95% CI 0.48, 0.78), 0.55 (95% CI 0.42, 0.72), and 0.55 (95% CI 0.41, 0.74), respectively. Analysis with RCS indicated an optimal TBIL/TC ratio threshold of 0.25%. Similar results were also observed in the validation cohort.

A higher TBIL/TC ratio was significantly associated with a reduced risk of CKD progression in patients with type 2 diabetes.

Diabetic cardiomyopathy is a unique cardiomyopathy that is common in diabetic patients, and it is also a diabetic complication for which no effective treatment is currently available. Moreover, relevant studies have revealed that a link exists between type 2 diabetes and heart failure and that abnormal thickening of EAT is inextricably linked to the development of diabetic heart failure. Numerous clinical studies have demonstrated that EAT is implicated in the pathophysiologic process of diabetic myocardial disease. In this overview, we will introduce the physiology, pathophysiology of the disease and potential therapeutic strategies, knowledge gaps, and future directions of the role of epicardial adipose tissue in type 2 diabetes mellitus and heart failure to promote the development of novel therapeutic approaches to improve the prognosis of patients with diabetic cardiomyopathy.

To ascertain the connection between normal-range urinary albumin-to-creatinine ratio (UACR) and all-cause mortality (ACM) among diabetic adults with preserved eGFR.

We used data from the 2003-2018 National Health and Nutrition Examination Survey. Nationally representative cross-sectional survey data linked with mortality outcomes from the National Death Index. Restricted cubic spline curves (RCS) and multivariable Cox regression models alongside subgroup analyses were utilised for estimating hazard ratios (HRs) and 95% confidence intervals (Cls) for UACR-ACM interplay, adjusting for demographic, socioeconomic, biochemical, medication and medical history factors. The UACR's predictive accuracy for survival outcomes was determined through receiver operating characteristic analysis.

The RCS regression analysis showcased that there was no significant evidence to support a nonlinear relationship between normal-range UACR and ACM (p = 0.080 for nonlinearity) in participants with diabetes mellitus (DM). In the model 2 adjusted for multiple confounding variables, the HR for ACM was 1.22 (95% CI, 1.06-1.40) per 10 mg/g raise in continuous UACR and 1.50 (95%CI, 1.18-1.91) for the high UACR tertile compared to the low. Kaplan-Meier analysis showed significantly lower survival rates in the medium and high UACR groups (p < 0.001). Subgroup analysis manifested a significant UACR-body mass index (BMI) interaction (p = 0.033 for interaction).

In DM adults without overt kidney dysfunction, elevated normal-range UACR was independently related to escalated ACM, particularly in those with normal BMI. To conclude, we underscore the significance of early risk assessment in DM patients with normal-range albuminuria, even without overt kidney dysfunction.

The clinical application of cyclosporine A (CsA) is limited due to nephrotoxicity. Lipid metabolism disorders play important roles in renal injury, but their role in CsA nephrotoxicity is not yet clear. Huangqi (Astragalus mongholicus Bunge) and Danshen (Salvia miltiorrhiza Bunge) (HD) play roles in ameliorating the nephrotoxicity of CsA, but their mechanisms still need to be fully clarified.

This study innovatively aimed to analyse the coexpression of renal proteins and serum metabolites for the identification of key pathways and targets. This study provides novel insight into the mechanism by which HD ameliorates CsA-induced nephrotoxicity.

We utilized HD to intervene in both in vivo and in vitro nephrotoxicity models induced by CsA. For the in vivo experiments, we constructed a coexpression network of renal proteins and serum metabolites, which was used to screen for key pathways. To validate these findings, we knocked down key proteins in vivo. For the in vitro studies, we employed MTT, Transwell, flow cytometry, and immunofluorescence assays to monitor the epithelial-mesenchymal transition (EMT) of HK-2 cells. Additionally, we used electron microscopy and Seahorse assays to examine the effects of HD on mitochondrial structure and function. Furthermore, we overexpressed Ppara to further confirm the mechanism by which HD improves renal function.

HD can improve renal pathological damage and function; regulate blood lipids, inflammation and oxidative stress indicators; and reduce apoptosis in renal tissues. Joint protein and metabolomics analyses revealed that two lipid metabolism-related pathways (the PPAR signalling pathway and linoleic acid metabolism pathway) were coenriched, involving six differential proteins (Cyp2e1, Cyp4a10, Gk, Lpl, Ppara, and Pck1) and two differentially abundant metabolites (alpha-Dimorphecolic acid and 12,13-EpOME). Western blot was used to verify differentially expressed proteins. HD improved mitochondrial damage and lipid accumulation, as demonstrated by transmission electron microscopy (TEM) analysis and Oil Red O staining. Knockdown of the key protein Ppara affected the expression of ACOX1 and exacerbated RF. In vitro verification demonstrated that HD significantly inhibited CsA-induced EMT in HK-2 cells and improved mitochondrial structure and function. Ppara overexpression promoted HD-mediated regulation of mitochondrial function, reduced apoptosis, and improved HK-2 RF.

HD can ameliorate CsA nephrotoxicity through renal protein-serum metabolism coexpression, the PPAR signalling pathway, and linoleic acid metabolism. HD-induced upregulation of Ppara to regulate lipid metabolism, improve mitochondrial function and reduce apoptosis are important mechanisms. The Ppara/ACOX1/TGF-β1 axis may play an important role in this process. These findings offer potential targets for the future development of therapeutic strategies and novel drugs.

Insulin resistance (IR) is the main pathological feature of polycystic ovary syndrome (PCOS), but the adverse impacts of IR on ovary and granulosa cells (GCs) are unknown. Therefore, the role of palmitic acid (PA) induced IR in GCs, and a mitochondrial proteostasis and mitochondrial homeostasis control system, the mitochondrial unfolded protein response (UPRmt)/mitophagy/lysosome axis were investigated to uncover the side effect and the mechanism of IR on GCs. Our results revealed that IR in GC was successfully constructed by 100 μM PA treatment accompanied with cell senescence. In addition, mitochondrial function was impaired by IR-induced GC senescence accompanied by significantly increased reactive oxygen species (ROS) and decreased mitochondrial membrane potential, and mitochondrial proteostasis was impaired by a dysfunctional UPRmt and increased protein aggregation, leading to more unfolded and misfolded proteins accumulating in mitochondria. Mitochondrial homeostasis was maintained by the mitophagy/lysosome degradation system, although mitophagy was significantly increased, lysosomes were damaged; hence, malfunctional mitochondria were not cleared by the mitophagy/lysosome degradation system, more ROS were produced by malfunctional mitochondria. Therefore, accelerated GC senescence was triggered by excessive ROS, and reversed by the mitophagy inhibitor cyclosporin A (CsA) accompanied with reduced IR. Additionally, the mice were administered with PA, and results revealed that the accelerated ovarian aging was caused by PA, which might be attributed to GC senescence. In conclusion, GC senescence was triggered in PA-induced IR by disruption of the UPRmt/mitophagy/lysosome axis, and IR induced GC senescence was reversed by the CsA.

Diabetic kidney disease (DKD) is one of the major complications of diabetes, and its pathological progression is closely associated with lipid metabolic reprogramming. Under diabetic conditions, renal cells undergo significant lipid metabolic abnormalities, including increased lipid uptake, impaired fatty acid oxidation, disrupted cholesterol efflux, and enhanced lipid catabolism, as adaptive responses to metabolic stress. These changes result in the accumulation of lipids such as free fatty acids, diacylglycerol, and ceramides, leading to lipotoxicity that triggers inflammation and fibrosis. Hypoxia in the DKD microenvironment suppresses fatty acid oxidation and promotes lipid synthesis through the HIF-1α pathway, while chronic inflammation exacerbates lipid metabolic disturbances via inflammatory cytokines, inflammasomes, and macrophage polarization. Targeting lipid metabolism represents a promising therapeutic strategy for alleviating DKD; however, further clinical translational studies are warranted to validate the efficacy and safety of these approaches.

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder that poses a significant global health burden due to its profound effects on systemic physiological homeostasis. Without timely intervention, the disease can progress insidiously, leading to multisystem complications such as cardiovascular, renal, and neuropathic pathologies. Consequently, pharmacological intervention becomes crucial in managing the condition. Leeches have been traditionally used in Chinese medicine for their potential to inhibit the progression of T2DM and its associated complications; however, the specific mechanisms underlying their action and target pathways remain poorly understood. The objective of this study was to predict potential therapeutic targets of leeches in the treatment of T2DM.

We collected active components and targets associated with leeches from four online databases, while disease-related targets were sourced from the GeneCards and OMIM databases. Following this, we performed Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Gene expression data were obtained from the GSE184050 dataset. Important immune cell types were identified through immunoinfiltration analysis in conjunction with single sample enrichment analysis (ssGSEA). Additionally, weighted co-expression network analysis (WGCNA) was utilized to identify significantly associated genes. Finally, we employed LASSO regression, SVM-RFE, XGBoost, and random forest algorithms to further predict potential targets, followed by validation through molecular docking.

Leeches may influence cellular immunity by modulating immune receptor activity, particularly through the activation of RGS10, CAPS2, and OPA1, thereby impacting the pathology of Type 2 Diabetes Mellitus (T2DM).

However, it is important to note that our results lack experimental validation; therefore, further research is warranted to substantiate these findings.

Background/Objectives: Type 2 diabetes mellitus (T2DM), is a rapidly growing global health concern, often accompanied by chronic kidney disease (CKD) and metabolic disturbances. Obesity-related indices, such as the visceral adiposity index (VAI) and body adiposity index (BAI), have been linked to cardiovascular and renal complications in diabetic patients. However, studies integrating both the atherogenic coefficient (AC) and prognostic nutritional index (PNI) for evaluating diabetic nephropathy (DN) remain limited. This study aimed to assess the associations of obesity-related indices with immunological and nutritional factors in patients with T2DM and prediabetes (PreDM). Methods: A retrospective, cross-sectional study was conducted over six months at a university clinical hospital in Dolj County, Romania. The study enrolled 268 newly diagnosed T2DM patients and 150 PreDM patients. Anthropometric parameters, laboratory tests, and demographic data were collected. AC and PNI were calculated using standard formulas, and statistical analyses were performed to determine their associations with metabolic and inflammatory markers. Results: Our study found that T2DM patients had significantly lower PNI values, indicating mild malnutrition, while PreDM patients maintained a normal nutritional status. AC was significantly higher in T2DM patients, correlating with lipid profile alterations and systemic inflammation. Obesity indices, particularly VAI, were significantly elevated in T2DM patients with higher AC values. Statistically significant differences in total cholesterol, low-density lipoprotein cholesterol (LDL-c), and triglycerides were observed between AC subgroups, reinforcing its role in cardiovascular risk assessment. Conclusions: The findings highlight the potential of AC and PNI as biomarkers for assessing nutritional, inflammatory, and lipemic status in diabetic patients. The significant associations between obesity-related indices, lipid profiles, and inflammation markers suggest that early assessment of these parameters may potentially aid in predicting diabetic complications. Further studies are needed to explore the clinical utility of AC and PNI in managing T2DM and CKD progression. Future research should investigate how the lipidic spectrum alters the progression of DN across various patient groups with diabetes and prediabetes.

Chronic kidney disease (CKD) is documented to cause alterations in lipid metabolism, and this was considered a potent driver of increased cardiovascular risk. Among the diverse alteration of lipid traits in CKD, research endeavours have predominantly concentrated on low-density lipoproteins (LDL) in view of the potent pro-atherogenic role of these lipoprotein particles and the demonstration of protective cardiovascular effect of reducing LDL. However, few studies have focused on the metabolism of triglyceride-rich lipoproteins and even fewer on their role in causing kidney damage. Therefore, the comprehensive description of the impact of hypertriglyceridemia (HTG) in CKD pathophysiology remains largely undetermined. This reflects the difficulty of disentangling the independent role of triglycerides (TG) in the complex, bidirectional relationship between TG and kidney disease. Abnormal neutral lipid accumulation in the intrarenal vasculature and renal cells eventually due to HTG may also promote glomerular injury, throughout mechanisms including oxidative stress, mitochondrial dysfunction and proinflammatory responses. While epidemiological and experimental evidence suggests a potential role of TG in kidney damage, the causal mechanisms and their clinical relevance remain unclear, representing a significant area for future investigation. This review aims to highlight the intricate interplay between TG metabolism and kidney disease, shedding light on the mechanisms through which HTG may influence kidney functionality.

Earlier studies have implicated a crucial link between diabetic nephropathy (DN) and the gut microbiota (GM) by considering the gut-kidney axis; however, the specific cause-and-effect connections between these processes remain unclear.

To compare changes in the GM between DN patients and control subjects, a review of observational studies was performed. The examination focused on the phylum, family, genus, and species/genus categories. To delve deeper into the cause-effect relationship, instrumental variables for 211 GM taxa (9 phyla, 16 classes, 20 orders, 35 families, and 131 genera), which were eligible for the mbQTL (microbial quantitative trait locus) mapping analysis, were collected from the Genome Wide Association Study (GWAS). A Mendelian randomization investigation was then conducted to gauge their impact on DN susceptibility using data from the European Bioinformatics Institute (EBI) and the FinnGen consortium. The European Bioinformatics Institute data included 1032 DN patients and 451,248 controls, while the FinnGen consortium data consisted of 3283 DN patients and 210,463 controls. Two-sample Mendelian randomization (TSMR) was utilized to determine the link between the GM and DN. The primary method for analysis was the inverse variance weighted (IVW) approach. Moreover, a reverse Mendelian randomization analysis was carried out, and the findings were validated through sensitivity assessments.

This review examined 11 observational studies that satisfied the inclusion and exclusion criteria. There was a significant difference in the abundance of 144 GM taxa between DN patients and controls. By employing the MR technique, 13 bacteria were pinpointed as having a causal link to DN (including 3 unknown GM taxa). Even after Bonferroni correction, the protective impact of the phylum Proteobacteria and genus Dialister (Sequeira et al. Nat Microbiol. 5:304-313, 2020; Liu et al. EBioMedicine. 90:104527, 2023) and the harmful impact of the genus Akkermansia, family Verrucomicrobiaceae, order Verrucomicrobia and class Verrucomicrobiae on DN remained significant. No noticeable heterogeneity or horizontal pleiotropy was detected in the instrumental variables (IVs). However, reverse MR investigations have failed to reveal any substantial causal relationship between DN and the GM.

Differences in the GM among DN patients and healthy controls are explored in observational studies. We verified the possible connection between certain genetically modified genera and DN, thereby emphasizing the connection between the "gut-kidney" axis and new insights into the GM's role in DN pathogenesis underlying DN. Investigations into this association are necessary, and novel biomarkers for the development of targeted preventive strategies against DN are needed.

Tissue fibrosis represents an aberrant repair process, occurring because of prolonged injury, sustained inflammatory response, or metabolic disorders. It is characterized by an excessive accumulation of extracellular matrix (ECM), resulting in tissue hardening, structural remodeling, and loss of function. This pathological phenomenon is a common feature in the end stage of numerous chronic diseases. Despite the advent of novel therapeutic modalities, including antifibrotic agents, these have only modest efficacy in reversing established fibrosis and are associated with adverse effects. In recent years, a growing body of research has demonstrated that exercise has significant benefits and potential in the treatment of tissue fibrosis. The anti-fibrotic effects of exercise are mediated by multiple mechanisms, including direct inhibition of fibroblast activation, reduction in the expression of pro-fibrotic factors such as transforming growth factor-β (TGF-β) and slowing of collagen deposition. Furthermore, exercise has been demonstrated to assist in maintaining the dynamic equilibrium of tissue repair, thereby indirectly reducing tissue damage and fibrosis. It can also help maintain the dynamic balance of tissue repair by improving metabolic disorders, exerting anti-inflammatory and antioxidant effects, regulating cellular autophagy, restoring mitochondrial function, activating stem cell activity, and reducing cell apoptosis, thereby indirectly alleviating tissue. This paper presents a review of the therapeutic potential of exercise and its underlying mechanisms for the treatment of a range of tissue fibrosis, including cardiac, pulmonary, renal, hepatic, and skeletal muscle. It offers a valuable reference point for non-pharmacological intervention strategies for the comprehensive treatment of fibrotic diseases.

Numerous studies have shown that dyslipidemia increases the risk of atherosclerotic cardiovascular disease (ASCVD) and significantly impacts the occurrence and progression of diabetic kidney disease (DKD). Early interventions for lipid metabolism disorders in DKD may improve renal function. This article reviews the clinical characteristics of dyslipidemia, mechanisms of lipid-induced renal injury, and advances in lipid-lowering therapy in DKD. We searched PubMed, Web of Science, and EMBASE to identify relevant articles, using keywords such as "diabetic kidney disease", "diabetic nephropathy", "diabetes", "dyslipidemia", "kidney", "cardiovascular disease", and "lipid therapy". High triglyceride (TG) and low high-density lipoprotein (HDL) are associated with increased risks of albuminuria and estimated glomerular filtration rate (eGFR) decline. Abnormal lipid metabolism may damage glomerular podocytes and renal tubular epithelial cells via ectopic lipid deposition, eventually impairing glomerular filtration function and increasing urinary albumin excretion. Lipid-lowering therapies can ameliorate lipid accumulation, downregulate inflammatory mediator expressions, and alleviate renal fibrosis. Fibrate and statin applications exhibit beneficial effects, reducing albuminuria and slowing eGFR decline in early DKD. However, the long-term effects of statins and fibrates on renal outcomes remain controversial. Pro-protein convertase subtilisin/kexin 9 (PCSK9)-targeted interventions have minimal side effects on the kidneys and seem effective in reducing inflammation and improving renal impairment compared with statins and fibrates. In addition, LDL apheresis (LDL-A) and double filtration plasmapheresis (DFPP) are promising clinical applications in diabetic patients with severe hypercholesterolemia or lipid-lowering drug intolerance.

A common observation in diabetic kidney disease is lipid accumulation, but the mechanism(s) underlying this pathology is unknown. Inhibition of Vascular endothelial growth factor B (VEGF-B) signaling was shown to prevent glomerular lipid accumulation and ameliorated diabetic kidney disease in experimental models. Here, we examined kidney biopsies from patients with Type 2 (84%) and Type 1 diabetes (16%), combined with data mining of RNA-seq dataset analyses in patients with diabetic kidney disease. In glomeruli, mesangial cell-derived VEGF-B expression was increased, and glomerular lipid accumulation positively correlated with impaired kidney function. Tubular lipid accumulation also associated with kidney dysfunction but was independent of tubular-derived VEGF-B expression. In vitro, the uptake of the fatty acid analogue, BODIPY-FA, was quantified. VEGF-B treatment increased BODIPY-FA uptake in endothelial cells, whilst pre-incubation with neutralizing antibodies against VEGF-B and its receptor VEGFR1 abolished this uptake. Transcriptome analyses of kidney and white adipose tissue from diabetic macaques showed that VEGF-B expression was higher in white adipose tissue than in kidney, and expression of VEGF-B was increased in white adipose tissue from patients with diabetic kidney disease. Analyses in diabetic transgenic mice demonstrated that expression of VEGF-B in adipocytes determined the lipolytic activity, dyslipidemia, kidney lipid accumulation and the development of diabetic kidney disease. Overall, VEGF-B is a regulator of kidney lipotoxicity in diabetic kidney disease, by controlling white adipose tissue lipolysis as well as endothelial fatty acid transport in glomeruli. Our data propose that assessment of kidney lipid accumulation, and VEGF-B expression can serve as biomarkers for early diabetic kidney disease.

Dyslipidemia is the leading cause of cardiovascular disease (CVD) in Type 2 diabetes mellitus patients. As a result, it is critical to target and manage the level of atherogenic lipids. Angiopoietin-like proteins 3 and 4 (ANGPTL 3 and ANGPTL 4) play an important role in the intravascular lipolysis of triglyceride-rich lipoproteins by blocking the enzyme lipoprotein lipase. This study aimed to determine the amounts of these angiopoietin-like proteins in T2DM and find their association with dyslipidemia in T2DM.

Sixty-one T2DM patients of age group 25-65 years and 27 healthy age-matched control participants were enrolled in the study. Glycemic status (FBS, PPBS, HbA1C), serum lipid parameters (cholesterol, TG, LDL, VLDL, HDL, Tc/HDL ratio), free fatty acid, serum insulin, and ANGPTL3, 4 were measured. A correlation was found between the ANGPTLs and the above parameters in T2DM patients.

Serum ANGPTL3 (P < 0.05) and ANGPTL4 (P < 0.001) were significantly decreased in T2DM. ANGPTL4 was also negatively correlated to PPBS (0.03), HbA1C (P = 0.05), and IR (P = 0.04). However, no such correlation was observed with ANGPTL 3. It was observed that lipid parameters were correlated with ANGPTL3 (LDL (P = 0.03), TC/HDL (P = 0.02)). There was a significant relationship between ANGPTL3 and 4 with FFA (P = 0.001 and P = 0.03, respectively).

This study shows that ANGPTL 3,4 may be associated with dyslipidemia in T2DM. ANGPTL4 is more correlated with glycemic status.

The aim of this study is to explore the impact of blood lipids and statins on renal function and all-cause mortality in patients with diabetic nephropathy (DN). PubMed, Embase, Web of Science, and Cochrane Library were systematically searched until April 9, 2024, for relevant studies of blood lipids and statins on renal function and all-cause mortality in patients with DN. After the selection, total cholesterol levels (TC), total triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), estimated glomerular filtration rate (eGFR), urinary albumin excretion (UAE), serum creati-nine (SCR), end-stage renal disease (ESRD), and all-cause mortality indexes were extracted for finally meta-analysis. In total, 25 papers containing 21,411 patients with DN were finally included in this study. Levels of TC and LDL-C, which are continuous variables, were higher in DN patients who developed ESRD [TC/weighted mean difference (WMD) = 0.517, 95 % confidence interval (CI): (0.223, 0.812), p = 0.001; LDL-C/WMD = 0.449, 95%CI: (0.200, 0.698), p < 0.001]. In addition, this study also observed that statins may reduce UAE levels [WMD = -46.814, 95% CI: (-71.767, -21.861), p < 0.001]. Finally, the survey indicated that statins may be associated with an ESRD reduction [HR = 0.884, 95% CI: (0.784, 0.998), p = 0.045]. Blood lipids, particularly TC and LDL-C, may slow the progression of DN to ESRD. Besides, statins may protect the kidneys by lowering the excretion of UAE levels and reducing the risk of ESRD. Based on the above outcomes, the findings of this study provided robust evidence-based medical support for the future prevention, surveillance, and management of DN.

Diabetes mellitus is a chronic metabolic disease that increasingly affects people every year. It is known that with its progression and poor management, metabolic changes can lead to organ dysfunctions, including kidneys. The study aimed to combine Raman spectroscopy and biochemical lipid profiling, complemented by machine learning (ML) techniques to evaluate chemical composition changes in kidneys induced by Type 2 Diabetes mellitus (T2DM). Raman spectroscopy identified significant differences in lipid content and specific molecular vibrations, with the 1777 cm-1 band emerging as a potential spectroscopic marker for diabetic kidney damage. The integration of ML algorithms improved the analysis, providing high accuracy, selectivity, and specificity in detecting these changes. Moreover, lipids metabolic profiling revealed distinct variations in the concentration of 11 phosphatydylocholines and 9 acyl-alkylphosphatidylcholines glycerophospholipids. Importantly, the correlation between Raman data and lipids metabolic profiling differed for control and T2DM groups. This study underscores the combined power of Raman spectroscopy and ML in offering a low-cost, fast, precise, and comprehensive approach to diagnosing and monitoring diabetic nephropathy, paving the way for improved clinical interventions. However, taking into account small number of data related to ethical committee approvals, the study should be verified on a larger number of cases.

Diabetic nephropathy (DN) is a leading cause of end-stage renal disease in patients with type 2 diabetes mellitus (T2DM). This meta-analysis aims to evaluate the association between the triglyceride glucose (TyG) index, a novel marker reflecting insulin resistance, and the risk of developing DN in patients with T2DM. We conducted a comprehensive literature search in PubMed, Embase, and Web of Science databases up to May 12, 2024. Studies assessing the TyG index in relation to DN risk among T2DM patients were included. The pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using a random-effects model. A total of eight longitudinal follow-up studies encompassing 15 889 patients with T2DM were included. The pooled analysis revealed a significant association between a higher TyG index and an increased risk of DN in patients with T2DM (RR=1.53, 95% CI: 1.37-1.71, p<0.001; I2=35%). The results of meta-regression analysis suggested that the cutoff of TyG index was positively associated with the RR for the association between TyG index and DN. Subgroup analyses demonstrated that the association was stronger in studies with cutoff of TyG index ≥9.5 as compared to those with the cutoff <9.5 (RR: 1.73 vs. 1.40, p for subgroup difference <0.05). The association was not significantly affected by study design, mean age of the patients, proportion of men, or follow-up durations. In conclusion, higher TyG index is significantly associated with an increased risk of DN in patients with T2DM.

Lipotoxicity plays a crucial role in the progression of diabetic kidney disease (DKD), yet the dynamic changes in renal lipid composition from diabetes to early-stage DKD remain unclear. Free fatty acids, lactosylceramides and cardiolipin (CL) were identified as the most significantly altered lipids by quantitatively comparing targeted lipids in the renal cortex of the classic spontaneous diabetic db/db mice using high-coverage targeted lipidomics. Further investigation into the causes and effects of decreased CL, which is a unique mitochondrial phospholipid, was conducted in mitochondria-rich renal proximal tubular cells by using western blotting, real-time PCR, immunohistochemistry and transmission electron microscopy. Reduced expression of cardiolipin synthase, a key enzyme in the CL synthesis pathway, and inhibition of CL-related mitophagy were confirmed under high glucose conditions. In addition, the protective effect of CL-targeted Szeto-Schiller 31 in preserving mitophagy was demonstrated in both in vivo and in vitro studies. These findings provide new insights into the pathogenesis of early-stage DKD from a lipid perspective and offer a theoretical basis for discovering new treatments.

The treatment options to delay the progression of diabetic nephropathy (DN), a key contributor to chronic kidney disease (CKD), are urgently needed. Previous studies reported that traditional Chinese medicine Panax notoginseng (PNG) exerted beneficial effects on DN. However, the renoprotective effects of Notoginsenoside R2 (NR2), an active component of PNG, on DN have not been investigated. This study aimed to assess the therapeutic potential of NR2 in DN and explore its underlying mechanisms.

In vivo models were developed using db/db mice, while in vitro models utilized HK-2 cells exposed to high glucose and palmitic acid (HGPA). Online databases and Cytoscape software were employed to predict the potential targets of NR2. The expression of associated proteins was measured using immunohistochemistry and western blot. Lipid accumulation, oxidative stress levels, mitochondrial function and cell apoptosis were also assessed. Small interfering RNA was used in in vitro experiments to examine the effect of c-Src.

NR2 ameliorated albuminuria, renal function and renal pathology in db/db mice. The activation of c-Src was suppressed in db/db mice and in HK-2 cells exposed to HGPA. NR2 inhibited JNK/STAT1 phosphorylation and CD36 overexpression. NR2 also ameliorated lipid accumulation, oxidative stress, mitochondrial dysfunction and cell apoptosis in vivo and in vitro. By inhibiting c-Src, HK-2 cells exposed to HGPA experienced less lipid deposition and mitochondrial damage, indicating the renoprotective effects of NR2 were correlated with the inhibition of c-Src.

NR2 ameliorated mitochondrial dysfunction and delayed the progression of DN partly through suppression of c-Src. The protective effects of NR2 might be related to a reduction in lipid accumulation.

Mizagliflozin (MIZ) is a specific inhibitor of sodium-glucose cotransport protein 1 (SGLT1) originally developed as a medication for diabetes.

To explore the impact of MIZ on diabetic nephropathy (DN).

Diabetic mice were created using db/db mice. They were administered either a low dose (0.5 mg/kg) or a high dose (1.0 mg/kg) of the SGLT1 inhibitor MIZ via stomach gavage for 8 weeks. Subsequently, mesangial cells (MCs) were isolated and subjected to high glucose conditions in culture to assess the effects of MIZ on DN.

The results showed that low doses of MIZ significantly reduced albuminuria to a level comparable to that achieved with high doses in db/db mice. High doses of MIZ led to a substantial increase in body weight in mice, along with decreased blood glucose levels and food intake. Moreover, the intervention with high-dose MIZ notably decreased the expression of extracellular matrix genes, such as collagen type 1 alpha 1 mRNA levels. While the expression of SGLT1 increased after exposure to high glucose, it decreased following treatment with MIZ. Furthermore, MIZ intervention was more effective in improving lactate dehydrogenase levels in MCs induced by high glucose compared to canagliflozin. MIZ also significantly elevated levels of antioxidant enzymes superoxide dismutase, catalase, and glutathione, while reducing malondialdehyde levels.

These findings indicate that MIZ can ameliorate DN by inhibiting SGLT1, inflammation, and oxidative stress.

Metabolic Syndrome (MS) is a cluster of metabolic risk factors, characterized by abdominal obesity, dyslipidemia, hypertension, insulin resistance, among others. The purpose of the study was to evaluate the astaxanthin (AXT) effects extracted from freshwater crab (Dilocarcinus pagei) at the Paraná Basin on lipotoxicity, lipid peroxidation and oxidative stress in the kidney of rats fed with a sucrose-rich diet (SRD). We hypothesized that daily administration of AXT prevents kidney damage by reducing lipotoxicity, lipid peroxidation, and reactive oxygen species (ROS), and by improving antioxidant enzyme defenses and crosstalk between NrF2 and NF-ĸB transcription factors. Male Wistar rats were fed a reference diet (RD), RD+AXT, SRD and SRD+AXT (AXT daily oral dose: [10 mg/kg body weight]) for 90 days. Systolic and diastolic blood pressure, biochemical assays in serum and urine were evaluated. Renal cortex samples were taken for histological analysis, determination of triglyceride content, ROS, thiobarbituric acid reactive substances (TBARS), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) enzyme activities and glutathione content (GSH). 4-HNE, NrF2, and NF-ĸB p65 expression were analyzed by immunohistochemistry. We demonstrated that daily oral supplementation of AXT to animals fed a SRD reduced systolic and diastolic blood pressure, histological renal damage, lipid accumulation, ROS and lipid peroxidation, and increased CAT and GPx activities. NrF2 protein expression in renal cortex was increased, whilst NF-ĸB p65 was reduced. AXT extracted from freshwater crabs (Dilocarcinus pagei) may be promising nutritional strategy for the prevention of renal alterations present in this model.

Diabetic nephropathy (DN) is one of the most common complications of diabetes. Our previous study showed that CD38 knockout (CD38KO) mice had protective effects on many diseases. However, the roles and mechanisms of CD38 in DN remain unknown. Here, DN mice were generated by high-fat diet (HFD) feeding plus streptozotocin (STZ) injection in male CD38KO and CD38flox mice. Mesangial cells (SV40 MES 13 cells) were used to mimic the injury of DN with palPagination Donemitic acid (PA) treatment in vitro. Our results showed that CD38 expression was significantly increased in kidney of diabetic CD38flox mice and SV40 MES 13 cells treated with PA. CD38KO mice were significantly resistant to diabetes-induced renal injury. Moreover, CD38 deficiency markedly decreased HFD/STZ-induced lipid accumulation, fibrosis, and oxidative stress in kidney tissue. In contrast, overexpression of CD38 aggravated PA-induced lipid accumulation and oxidative stress. CD38 deficiency increased expression of SIRT3, while overexpression of CD38 decreased its expression. More importantly, 3-TYP, an inhibitor of SIRT3, significantly enhanced PA-induced lipid accumulation and oxidative stress in CD38 overexpressing cell lines. In conclusion, our results demonstrated that CD38 deficiency prevented DN by inhibiting lipid accumulation and oxidative stress through activation of the SIRT3 pathway.

Obesity is a significant health concern due to its rapid increase worldwide. It has been linked to the pathogenic factors of renal diseases, cancer, cardiovascular diseases, hypertension, dyslipidemia, and type 2 diabetes. Notably, obesity raises the likelihood of developing chronic kidney disease (CKD), leading to higher adult mortality and morbidity rates. This study explores the molecular mechanisms that underlie obesity-associated nephropathy and its clinical implications. Obesity-Associated Nephropathy (OAN) develops and worsens due to insulin resistance and hyperinsulinemia, which promote renal sodium reabsorption, glomerular hyperfiltration, and hypertension, leading to progressive kidney damage. Renal damage is further aggravated by persistent inflammation and redox damage, mediated by adipokines and proinflammatory cytokines, such as TNF-α and IL-6. Furthermore, stimulation of the sympathetic nervous system and the renin-angiotensin- aldosterone system (RAAS) intensifies glomerular hypertension and fibrosis. These elements cause glomerular hyperfiltration, renal hypertrophy, and progressive kidney damage. Clinical manifestations of obesity-associated nephropathy include proteinuria, reduced glomerular filtration rate (GFR), and ultimately, CKD. Management strategies currently focus on lifestyle modifications, such as weight loss through diet and exercise, which have been effective in reducing proteinuria and improving GFR. Pharmacological treatments targeting metabolic pathways, including GLP-1 receptor agonists and SGLT2 inhibitors, have shown renoprotective properties. Additionally, traditional RAAS inhibitors offer therapeutic benefits. Early detection and comprehensive management of OAN are essential to prevent its progression and lessen the burden of CKD.

Obesity-related glomerulopathy (ORG) represents an escalating public health with no effective treatments currently available. Abnormal lipid metabolism and lipid droplet deposition in the kidneys are key contributors to ORG. Cyanidin-3-glucoside (C3G) has shown potential in regulating lipid metabolism and may offer reno-protective effects; however, its therapeutic efficacy and underlying mechanisms in ORG remain unclear. An ORG mouse model was established, followed by an 8-week C3G intervention. The mice were divided into three groups: normal control (CT) group, ORG group, and C3G treatment group. Fecal 16S rRNA sequencing, metabolomics of feces-serum-kidney, and kidney single-cell RNA sequencing (scRNA-seq) were performed to investigate the effects and mechanisms of C3G. Compared to CT mice, ORG mice exhibited elevated serum CHO, TG, Cys-C, UACR, urinary Kim-1, and NAG levels, along with glomerular hypertrophy and tubular injury. These biochemical and pathological indicators improved following C3G treatment. Fecal 16S analysis revealed reduced gut microbiota diversity in ORG mice compared to CT mice, while C3G intervention increased gut microbiota diversity. Metabolic profiling of feces, serum, and kidney indicated reprogramming of glycerophospholipid metabolism in ORG mice, ameliorated by C3G treatment. Further analysis demonstrated that abnormal glycerophospholipid metabolites correlated with blood lipids, urinary protein, urinary tubular injury markers, and gut microbiota, specifically Lachnospiraceae and Blautia. Additionally, scRNA-seq analysis identified activation of the PPARγ/CD36 pathway in proximal tubule cells (PTCs) of ORG mice. C3G improved abnormal glycerophospholipid metabolism and alleviated injury in PTCs by inhibiting the PPARγ/CD36 pathway. C3G reduces lipid droplet accumulation in the PTCs of ORG mice by modulating the gut microbiota and inhibiting the PPARγ/CD36 pathway. These findings offer new insights and therapeutic targets for ORG.

Diabetic kidney disease (DKD), which is emerging as a pervasive global health concern and a considerable economic burden, is characterized by a detrimental effect on renal function and structure. Recent research indicates that the progression of DKD is facilitated by lipotoxic injury to tubular epithelial cells (TECs). However, the specific mechanisms that contribute to this cellular damage have yet to be fully elucidated. Our results revealed a significant upregulation of F2RL1 in vivo and in vitro models, which was positively correlated with the expression of inflammatory factors. Knockdown of F2RL1 significantly reduced inflammatory response in palmitate-stimulated HK-2 cells. Mechanistically, F2RL1 might exacerbate lipotoxicity-induced DKD through the modulation of the Hippo signaling pathway. Collectively, these findings suggest that modulating F2RL1 expression may be a strategic approach to mitigate the inflammatory damage to RTECs associated with DKD, potentially through its involvement in the Hippo signaling pathway. Given these findings, F2RL1 merits consideration as a candidate therapeutic target for DKD.

Diphenyl diselenide (DPDS) ameliorates nephropathy in streptozotocin (STZ)-induced type 1 diabetic rats by inhibiting oxidative stress and inflammatory reactions. However, it has not been clarified whether DPDS alleviates type 1 diabetic kidney disease (DKD) is related to the inhibition of extracellular matrix (ECM) production and the regulation of intestinal flora disorder.

The present study investigated the effects of DPDS on ECM generation in the kidney and intestinal microflora composition in feces. The rats were orally administered DPDS or metformin for eight weeks. Various indices were measured to assess the severity of renal injury. After euthanizing the rats, oxidative stress markers in serum and kidney were assessed using biochemical methods, and the expressions of ECM-related proteins in kidney were analyzed using Western blot. Additionally, 16S rRNA high-throughput sequencing was used to evaluate the diversity and composition of the intestinal flora in feces.

The results showed DPDS and metformin improved the DKD in STZ rats, as evidenced by decreased blood glucose, BUN, urine volume, urine microalbumin, urinary β2 microglobulin, and improvement of renal pathological morphology. Furthermore, DPDS intervention markedly reduced the protein expression of α-SMA, COI Ⅳ, FN, and vimentin in the kidneys. Besides, DPDS not only improved dyslipidemia in STZ diabetic rats, but also enhanced the activities of antioxidant enzymes, decreased the level of MDA in serum and kidney, and regulated the expression of proteins related to the Nrf2/Keap1 signaling pathway in the kidney. Moreover, we found that DPDS could selectively improve the relative abundance of probiotics as well as the diversity of flora, thus ameliorating the intestinal microbial composition of the STZ rats, significantly regulating the intestinal microbial homeostasis.

Overall, DPDS inhibited ECM production and improved renal pathological changes, which may be related to reducing oxidative stress damage in the kidney and improving intestinal flora imbalance, providing data support for the further development and application of DPDS in DKD.

Lipotoxicity has been implicated in diabetic kidney disease (DKD). However, the role of high glucose levels in DKD and the underlying renal protective mechanisms of GLP-1 receptor agonists (GLP-1RAs) remain unclear.

To investigate cholesterol accumulation, pyroptosis in glomerular endothelial cells (GEnCs), and the renal protective mechanisms of GLP-1RAs, we used various techniques, including RT-qPCR, Oil Red O staining, Western blotting, lactate dehydrogenase (LDH) activity assays, circRNA microarrays, bioinformatics analysis, gain and loss-of-function experiments, rescue experiments, and luciferase assays. Additionally, in vivo experiments were conducted using C57BL/6J and ApoE-deficient (ApoE-/-) mice.

GEnCs exposed to high glucose exhibited reduced cholesterol efflux, which was accompanied by downregulation of ATP-binding cassette transporter A1 (ABCA1) expression, cholesterol accumulation, and pyroptosis. Circ8411 was identified as a regulator of ABCA1, inhibiting miR-23a-5p through its binding to the 3'UTR. Additionally, higher glucose levels decreased circ8411 expression by inhibiting RXRα. GLP-1RAs effectively reduced cholesterol accumulation and cell pyroptosis by targeting the RXRα/circ8411/miR-23a-5p/ABCA1 pathway. In diabetic ApoE-/- mice, renal structure and function were impaired, with resulted in increased cholesterol accumulation and pyroptosis; however, GLP-1RAs treatment reversed these detrimental changes.

These findings suggest that the RXRα/circ8411/miR-23a-5p/ABCA1 pathway mediates the contribution of high glucose to lipotoxic renal injury. Targeting this pathway may represent a potential therapeutic strategy for patients with DKD and hypercholesterolemia. Moreover, GLP-1RAs may provide renal protective effects by activating this pathway.

This study is intended to explore the effect of hypoxia-inducible factor-1α (HIF-1α) activation on lipid accumulation in the diabetic kidney. A type 1 diabetic rat model was established by STZ intraperitoneal injection. Cobalt chloride (CoCl2) and YC-1 were used as the HIF-1α activator and antagonist, respectively. CoCl2 treatment significantly increased HIF-1α expression, accelerated lipid deposition, and accelerated tubular injury in diabetic kidneys. In vitro, CoCl2 effectively stabilized HIF-1α and increased its transportation from the cytoplasm to the nucleus, which was accompanied by significantly increased lipid accumulation in HK-2 cells. Furthermore, results obtained in vivo showed that HIF-1α protein expression in the renal tubules of diabetic rats was significantly downregulated by YC-1 treatment. Meanwhile, lipid accumulation in the tubules of the DM + YC-1 group was markedly decreased in comparison to the DM + DMSO group. Accordingly, PAS staining revealed that the pathological injury caused to the tubular epithelial cells was alleviated by YC-1 treatment. Furthermore, the blood glucose level, urine albumin creatinine ratio, and NAG creatinine ratio in the DM + YC-1 group were significantly decreased compared to the DM + DMSO group. Moreover, the protein expression levels of transforming growth factor β1 (TGF-β1) and connective tissue growth factor (CTGF) in diabetic kidneys were decreased by YC-1 treatment. Our findings demonstrate that the activation of HIF-1α contributed to interstitial injury in a rat model of diabetic nephropathy and that the underlying mechanism involved the induction of lipid accumulation.

This study aimed to investigate the correlations between estimated small dense low-density lipoprotein-cholesterol (esd-LDL-c) and the development of end-stage kidney disease (ESKD), cardiovascular mortality, and all-cause mortality in individuals with diabetic kidney disease (DKD) or diabetes mellitus (DM) concomitant chronic kidney disease (CKD).

We analyzed the data from a biopsy-proven DKD cohort conducted at West China Hospital of Sichuan University between 2009 and 2021 (the DKD cohort) and participants with DM and CKD in the National Health and Nutrition Examination Survey (NHANES) 2011-2014 (the NHANES DM-CKD cohort). Cox regression analysis was also used to estimate associations between esd-LDL-c and the incidence of ESKD, cardiovascular mortality, and all-cause mortality.

There were 175 ESKD events among 338 participants in the DKD cohort. Patients were divided into three groups based on esd-LDL-c tertiles (T1 < 33.7 mg/dL, T2 ≥ 33.7 mg/dL to <45.9 mg/dL, T3 ≥ 45.9 mg/dL). The highest tertile of esd-LDL-c was associated with ESKD (adjusted HR 2.016, 95% CI 1.144-3.554, p = .015). Furthermore, there were 99 deaths (39 cardiovascular) among 293 participants in the NHANES DM-CKD cohort. Participants were classified into three groups in line with the tertile values of esd-LDL-c in the DKD cohort. The highest tertile of esd-LDL-c was associated with cardiovascular mortality (adjusted HR 3.95, 95% CI 1.3-12, p = .016) and all-cause mortality (adjusted HR 2.37, 95% CI 1.06-5.32, p = .036).

Higher esd-LDL-c was associated with increased risk of ESKD in people with biopsy-proven DKD, and higher cardiovascular and all-cause mortality risk among those with DM-CKD.

Diabetic nephropathy (DN) and obesity bring a huge burden to society. Obesity plays a crucial role in the progression of type 2 DN, but the pathophysiology remains unclear. Thus, we aimed the explore the association between type 2 DN and obesity using bioinformatics method. The gene expression profiles of type 2 DN (GSE96804) and obesity (GSE94752) were downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) were screened with the thresholds defined as |log2FC| ≥1 and P<0.05. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed. Subsequently, a protein-protein interaction network was constructed based on the STRING database. Hub genes were identified, and the co-expression network was constructed. Finally, the hub genes were verified in clinical samples of 24 patients by immunohistochemistry. A total of 17 common DEGs were identified. Finally, two overlapping hub genes were identified (CCL18, C1QC). C1QC has been verified in clinical specimens. Using bioinformatics methods, the present study analyzed the common DEGs and the potential pathogenic mechanisms involved in type 2 DN and obesity. C1QC was the hub gene. Further studies are needed to clarify the specific relationships among C1QC, type 2 DN and obesity.

Abnormal renal lipid metabolism causes renal lipid deposition, which leads to the development of renal fibrosis in diabetic kidney disease (DKD). The aim of this study was to investigate the effect and mechanism of chlorogenic acid (CA) on reducing renal lipid accumulation and improving DKD renal fibrosis.

This study evaluated the effects of CA on renal fibrosis, lipid deposition and lipid metabolism by constructing in vitro and in vivo models of DKD, and detected the improvement of Notch1 and Stat3 signaling pathways. Molecular docking was used to predict the binding between CA and the extracellular domain NRR1 of Notch1 protein.

In vitro studies have shown that CA decreased the expression of Fibronectin, α-smooth muscle actin (α-SMA), p-smad3/smad3, alleviated lipid deposition, promoted the expression of carnitine palmitoyl transferase 1 A (CPT1A), and inhibited the expression of cholesterol regulatory element binding protein 1c (SREBP1c). The expression of Notch1, Cleaved Notch1, Hes1, and p-stat3/stat3 were inhibited. These results suggested that CA might reduce intercellular lipid deposition in human kidney cells (HK2) by inhibiting Notch1 and stat3 signaling pathways, thereby improving fibrosis. Further, in vivo studies demonstrated that CA improved renal fibrosis and renal lipid deposition in DKD mice by inhibiting Notch1 and stat3 signaling pathways. Finally, molecular docking experiments showed that the binding energy of CA and NRR1 was -6.6 kcal/mol, which preliminarily predicted the possible action of CA on Notch1 extracellular domain NRR1.

CA reduces renal lipid accumulation and improves DKD renal fibrosis by inhibiting Notch1 and stat3 signaling pathways.

Emerging data have revealed that damage to tubular epithelial cell is a driving force in the progression of diabetic kidney disease (DKD). However, the specific mechanisms by which lipotoxicity contributes to the injury of these cells, thereby influencing the development of DKD, are yet to be fully understood. Here, we analyzed the GSE 30529 microarray datasets of human tubulointerstitial tissue samples from the Gene Expression Omnibus database (GEO). Concurrently, we conducted RNA-sequencing on palmitic acid (PA)-treated human renal proximal tubule epithelial cells (HK2 cells). After normalization, the differentially expressed genes (DEGs) were screened by R software and gene ontology (GO) enrichment analysis was conducted, and lysosomal-associated protein transmembrane 5 (LAPTM5) was finally selected. Our findings indicate that the expression of LAPTM5 was obviously increased in DKD patients, and the correlation between LAPTM5, and other clinical parameters of DKD was analyzed using the Spearman correlation analysis. The potential of LAPTM5 as a prognostic biomarker for DKD was further consolidated through receiver operating characteristic (ROC) analysis. To further verify the function of LAPTM5, we established mouse or in vitro systems mimicking DKD. The results showed that a consistent upregulation of LAPTM5, which was also found to be linked with inflammatory mediators within the context of DKD. Additionally, LAPTM5 silencing significantly downregulated mRNA expression of inflammatory factors in PA-treated HK2 cells. These results indicate that LAPTM5 is a potential biomarker and therapeutic treatment target for DKD. This discovery paves the way for future research and development of targeted interventions aimed at mitigating the progression of this prevalent condition.