In inflammatory bowel disease therapy, thiopurines have been essential.　However, several reports have investigated factors affecting thiopurine metabolism to date.　This study investigated factors affecting intracellular concentrations of 6-thioguanine nucleotide (6-TGN) and 6-methylmercaptopurine (6-MMP) in a real-world setting.

Between May 2013 and October 2021 in one institution, 44 patients (median age 44 years;male 35, female 9;ulcerative colitis 32, Crohn's disease 12) receiving thiopurines were reviewed.　Intracellular 6-TGN/6-MMP concentrations were measured by high-performance liquid chromatography, and the initial measurement in each patient was used for the study.

The 6-TGN level was significantly higher in females, with mild disease activity, absence of NUDT15 polymorphism, and allopurinol administration.　A higher trend was observed with high thiopurine dosage (>50 mg).　6-MMP levels were significantly lower with concomitant use of time-dependent 5-aminosalicylic acid (5-ASA) and allopurinol, and higher with high thiopurine dosage.　On multivariate analysis of variance, logarithmically transformed 6-TGN levels were significantly higher in females, with high thiopurine dosage, and allopurinol administration.　Similarly, logarithmically transformed 6-MMP levels were significantly higher with time-dependent 5-ASA administration and high thiopurine dosage.

Patients who received allopurinol, a high dose of thiopurine, or were female showed higher 6-TGN levels.

Crohn's disease [CD] and ulcerative colitis [UC] require lifelong treatment and patient monitoring. Current biomarkers have several limitations; therefore, there is an unmet need to identify novel biomarkers in inflammatory bowel disease [IBD]. Previously, the role of plasminogen activator inhibitor 1 [PAI-1] was established in the pathogenesis of IBD and suggested as a potential biomarker. Therefore, we aimed to comprehensively analyse the selectivity of PAI-1 in IBD, its correlation with disease activity, and its potential to predict therapeutic response.

Blood, colon biopsy, organoid cultures [OC], and faecal samples were used from active and inactive IBD patients and control subjects. Serpin E1 gene expressions and PAI-1 protein levels and localisation in serum, biopsy, and faecal samples were evaluated by qRT-PCR, ELISA, and immunostaining, respectively.

The study population comprised 132 IBD patients [56 CD and 76 UC] and 40 non-IBD patients. We demonstrated that the serum, mucosal, and faecal PAI-1 concentrations are elevated in IBD patients, showing clinical and endoscopic activity. In responders [decrease of eMayo ≥3 in UC; or SES-CD  50% in CD], the initial PAI-1 level decreased significantly upon successful therapy. OCs derived from active IBD patients produced higher concentrations of PAI-1 than the controls, suggesting that epithelial cells could be a source of PAI-1. Moreover, faecal PAI-1 selectively increases in active IBD but not in other organic gastrointestinal diseases.

The serum, mucosal, and faecal PAI-1 concentration correlates with disease activity and therapeutic response in IBD, suggesting that PAI-1 could be used as a novel, non-invasive, disease-specific, faecal biomarker in patient follow-up.

The conversion of azathioprine (AZA) to active 6-thioguanine nucleotides (6-TGN) is essential for its clinical efficacy; however, another metabolite formed, 6-methylmercaptopurine (6-MMP), is related to hepatotoxicity. Blood samples were collected from 37 patients under AZA's treatment, and a new HPLC-UV method was validated and applied for simultaneous quantification of 6-TGN and 6-MMP in erythrocytes of Crohn's disease (CD) patients. The concentration of 6-TGN and 6-MMP found ranged from 4.5 to 2,456 ρmol/8 × 108 red blood cells (RBCs) for 6-TGN and from 170 to 53,951 ρmol/8 × 108 RBCs for 6-MMP. Reduced levels of 6-MMP in patients into combo therapy with AZA and allopurinol (2,031 ρmol/8 × 108 RBCs) have been observed when compared to patients undergoing monotherapy with AZA (9,098 ρmol/8 × 108 RBCs). Additionally, there was a negative correlation (r = -83.7%, P < 0.05) between lymphocyte count and 6-TGN levels. The method developed is reliable, accurate and reproducible and can be used as an important tool in the monitoring routine of patients with CD under AZA treatment, allowing the individualization of the dose, monitoring adherence to the treatment and the evaluation of the clinical outcome of these patients.

Despite new treatment options for inflammatory bowel disease (IBD), conventional thiopurines remain a common treatment option for maintaining remission, particularly in non-Westernized countries. Therapeutic drug monitoring (TDM) is advised in standard care for optimizing therapy strategies to improve effectiveness, reveal nonadherence and reduce toxicity. Still, the rationale of TDM is debated.

Key insights on TDM of thiopurine metabolites are discussed. The pharmacology of thiopurines is described, emphasizing the interindividual differences in pharmacogenetics, pharmacokinetics and pharmacodynamics. Pharmacological differences between conventional thiopurines and tioguanine are outlined. Finally, several optimization strategies for thiopurine therapy in IBD are discussed.

TDM has been a useful, but limited, tool to individualize thiopurine therapy. Pharmacokinetic data on the active thiopurine metabolites, derived from measurements in erythrocytes, associated with clinical response only partially predict effectiveness and toxicity. An additional pharmacodynamic marker, such as Rac1/pSTAT3 expression in leukocytes, may improve applicability of TDM in the future.

Polymorphisms in the nucleotide diphosphate-linked moiety X-type motif 15 (NUDT15) gene are associated with thiopurine-induced leukopenia in patients with inflammatory bowel disease (IBD). NUDT15-associated subcellular thiopurine metabolism has not been investigated in primary lymphocytes. We hypothesized that NUDT15 mutation increases DNA-incorporated deoxythioguanosine (dTG) and induces apoptosis in lymphocytes.

DNA-incorporated dTG in peripheral blood mononuclear cells (PBMCs) and 6-thioguanine nucleotides (6-TGN) in red blood cells were measured in patients with IBD undergoing thiopurine treatment. The association of a single nucleotide polymorphism for NUDT15 (rs116855232) with dTG^PBMC was examined. The pro-apoptotic effect of DNA-incorporated dTG was examined ex vivo in association with NUDT15 genotypes by co-culturing patient-derived peripheral CD4⁺ T lymphocytes with 6-thioguanine (6-TG).

dTG^PBMC was significantly higher in NUDT15 variants than in non-variants. dTG^PBMC, but not 6-TGN^RBC, negatively correlated with peripheral lymphocyte counts (r =  - 0.31 and  - 0.12, p = 0.012 and 0.173, respectively). DNA-incorporated dTG significantly accumulated to a greater extent in lymphocytes from NUDT15 variants when co-cultured with 6-TG ex vivo than in those from non-variants and was associated with decreased proliferation and increased apoptosis.

Increased DNA-incorporated dTG may be responsible for thiopurine-induced leukocytopenia through cell apoptosis in IBD patients with NUDT15 mutation.

This study aimed to compare fecal calprotectin (FC) levels with other commonly used parameters as part of patient care during evaluation for inflammatory bowel disease (IBD).

We recruited adult IBD patients with ulcerative colitis (UC) and Crohn's disease (CD) and compared the results of the patient's biopsy results (i.e., inflamed versus noninflamed) for six sites (i.e., ileum, ascending colon, transverse colon, descending colon, sigmoid colon, rectum) with concentrations of C-reactive protein (CRP), total leucocytes and fecal calprotectin (FC).

We found that FC was significantly elevated in a concentration-dependent manner that correlated with the number of active inflammation sites reported in biopsy. Although CRP and leucocyte measurements trended upwards in line with inflammation reported from biopsy, the results were highly variable and highlighted poor reliability of these biomarkers for indicating IBD inflammation.

These results strongly suggest that FC correlates best with biopsy reports and is a superior marker than CRP and leucocytes.

A missense variant of the nucleoside diphosphate-linked moiety X-type motif 15 (NUDT15) gene (R139C) predisposes Asian patients with inflammatory bowel disease (IBD) to thiopurine-induced leukopenia. This study evaluates the long-term effect of NUDT15 R139C heterozygosity on hematological parameters during thiopurine administration.

We enrolled 83 Japanese IBD patients who were on anti-tumor necrosis factor-α agents and had used thiopurine. NUDT15 R139C was genotyped by polymerase chain reaction. We retrospectively reviewed patient clinical charts to collect data on white blood cell (WBC) count, mean corpuscular volume (MCV), hemoglobin, and platelet count during the 24 months following thiopurine initiation.

The included patients had either Crohn's disease (54; 65.1%) or ulcerative colitis (29; 34.9%). Genotyping of NUDT15 R139C identified 62 patients (74.7%) of genotype C/C and 21 (25.3%) of genotype C/T. The median dose of thiopurine was lower in the C/T group than in the C/C group after starting thiopurine. At 6 months, the mean WBC count of the C/T group became significantly lower than that of the C/C group (P = 0.008) and remained lower through the 24 months. The C/T group developed grade 2-4 leukopenia by 6 months, which persisted through 12-24 months. The mean MCV in the C/T group became higher than that of the C/C group after 3 months.

NUDT15 R139C heterozygosity affected the WBC count and MCV for 24 months after thiopurine administration. Our results indicate that careful monitoring of leukopenia and dose adjustment are necessary throughout treatment in IBD patients heterozygous for the NUDT15 R139C.

Therapeutic drug monitoring of thiopurine erythrocyte levels is not available in all centers and it usually requires quite a long time to obtain the results. The aims of this study were to build a model predicting low levels of 6-thioguanine and 6-methylmercaptopurine in pediatric inflammatory bowel disease (IBD) patients and to build a model to predict nonadherence in patients treated with azathioprine (AZA).

The study consisted of 332 observations in 88 pediatric IBD patients. Low AZA dosing was defined as 6-thioguanine levels <125 pmol/8 × 10 erythrocytes and 6-methylmercaptopurine levels <5700 pmol/8 × 10 erythrocytes. Nonadherence was defined as undetectable levels of 6-thioguanine and 6-methylmercaptopurine <240 pmol/8 × 10 erythrocytes. Data were divided into training and testing part. To construct the model predicting low 6-thioguanine levels, nonadherence, and the level of 6-thioguanine, the modification of random forest method with cross-validation and resampling was used.

The final models predicting low 6-thioguanine levels and nonadherence had area under the curve, 0.87 and 0.94; sensitivity, 0.81 and 0.82; specificity, 0.80 and 86; and distance, 0.31 and 0.21, respectively, when applied on the testing part of the dataset. When the final model for prediction of 6-thioguanine values was applied on testing dataset, a root-mean-square error of 110 was obtained.

Using easily obtained laboratory parameters, we constructed a model with sufficient accuracy to predict patients with low 6-thioguanine levels and a model for prediction of AZA treatment nonadherence (web applications: https://hradskyo.shinyapps.io/6TG_prediction/ and https://hradskyo.shinyapps.io/Non_adherence/).

With the advent of biologic therapies for the treatment of inflammatory bowel disease, the roles of thiopurines have continued to evolve. This review will focus on recent advances in pharmacology and the safety and efficacy of thiopurines as maintenance therapies for steroid-induced remissions and post-surgical maintenance of remission and as combination therapies to reduce immunogenicities of biologic agents.

Due to pharmacogenetics of thiopurine S-methyltransferase, thiopurine dosing is more effectively based on monitoring of thiopurine metabolites rather than weight-based dosing. Thiopurines continue to have a role as maintenance therapy after steroid-induced remissions and in combination with biologics to induce and maintain remission. Safety monitoring includes measurements of blood counts, liver chemistries, and dermatologic evaluations and protection from sun exposure. Thiopurines appear to be safe during pregnancies and while very uncommon, lymphomas (including hepatosplenic T cell lymphomas) remain a recognized risk, particularly in younger and older males.

The use of thiopurines in the treatment of inflammatory bowel disease (IBD) can be optimized by the application of therapeutic drug monitoring. In this procedure, 6-thioguanine nucleotides (6-TGN) and 6-methylmercaptopurine (6-MMP) metabolites are monitored and related to therapeutic response and adverse events, respectively. Therapeutic drug monitoring of thiopurines, however, is hampered by several analytical limitations resulting in an impaired translation of metabolite levels to clinical outcome in IBD. Thiopurine metabolism is cell specific and requires nucleated cells and particular enzymes for 6-TGN formation. In the current therapeutic drug monitoring, metabolite levels are assessed in erythrocytes, whereas leukocytes are considered the main target cells of these drugs. Furthermore, currently used methods do not distinguish between active nucleotides and their unwanted residual products. Last, there is a lack of a standardized laboratorial procedure for metabolite assessment regarding the substantial instability of erythrocyte 6-TGN. To improve thiopurine therapy in patients with IBD, it is necessary to understand these limitations and recognize the general misconceptions in this procedure.

Thiopurines are the prerequisite for immunomodulation in inflammatory bowel disease (IBD) therapy. When administered in high (oncological) dose, thiopurine metabolites act as purine antagonists, causing DNA-strand breakage and myelotoxicity. In lower IBD dosages, the mode of action is primarily restricted to anti-inflammatory effects. Then, myelosuppression and hepatotoxicity are the most common adverse events of thiopurines. The aim of this study was to assess the effect of thiopurine metabolites on hematologic and hepatic parameters and to determine which patient characteristics are related to generation of thiopurine metabolites.

The authors scrutinized the therapeutic drug monitoring database of the VU University medical center and subsequently merged this database with the Clinical Laboratory database of our hospital covering the same time period (2010-2015).

The authors included 940 laboratory findings of 424 unique patients in this study. Concentrations of 6-thioguanine nucleotides (6-TGN) correlated negatively with red blood cell count, white blood cell count, and neutrophil count in both azathioprine (AZA) and mercaptopurine users. There was a positive correlation with mean corpuscular volume. In patients using 6-thioguanine, 6-TGN concentrations correlated positively with white blood cell count. Furthermore, there was an inverse correlation between patient's age and 6-TGN concentrations in patients using AZA or 6-thioguanine, and we observed an inverse correlation between body mass index and 6-TGN concentrations in patients using AZA or mercaptopurine. No relations were observed with liver test abnormalities.

Thiopurine derivative therapy influenced bone marrow production and the size of red blood cells. Age and body mass index were important pharmacokinetic factors in the generation of 6-TGN.

The single nucleotide polymorphism (SNP) c.415C>T in exon 3 of NUDT15 affects thiopurine-induced leukopenia in Asian patients with Crohn's disease. Meanwhile, three additional genetic variants of NUDT15 were reported in patients with acute lymphoblastic leukemia. We evaluated the effects of these additional genetic variants of NUDT15 in patients with inflammatory bowel disease (IBD) treated with thiopurines.

Ninety-six Japanese patients with IBD were enrolled. Genotyping for the NUDT15 and TPMT genes was performed using Custom TaqMan SNP genotyping assays or Sanger sequencing. The changes in white blood cell (WBC) count, mean corpuscular volume (MCV), platelet count, hemoglobin, CRP, amylase, albumin, AST, ALT, and ESR were evaluated.

Genetic variants of exon 1 and exon 3 of NUDT15 were identified in 24 of 96 patients (25.0%). C.52G > A and c.36_37insGGAGTC in exon 1 were found in three patients each. All three patients with c.36_37insGGAGTC in exon 1 were heterozygotes of p.Arg139Cys in exon 3. Eighteen patients had p.Arg139Cys in exon 3 alone. The WBC count gradually decreased after initiation of thiopurine treatment in the mutated cases (n = 24), and was significantly lower at 6, 8, 10, and 16 wk (P = 0.0271, 0.0037, 0.0051, and 0.0185, respectively). The WBC counts were also evaluated in patients with and without prednisolone treatment. In the patients with prednisolone treatment, the WBC count tended to show a greater decrease in the mutated cases, with significant differences at 8 and 10 wk (P = 0.012 and 0.029, respectively). In the patients without prednisolone treatment, the WBC count was significantly lower at 2, 4, 8, and 14 wk in mutated cases (P = 0.0196, 0.0182, 0.0237 and 0.0241, respectively). MCV increased after starting thiopurine treatment in the mutated cases, and was significantly higher at 10 wk (P = 0.0085). Platelet count, hemoglobin, CRP, amylase, albumin, AST, ALT and ESR did not differ significantly between the wild-type and mutated cases. TPMT mutations were not found in any of the patients.

Mutations in exon 1 of NUDT15 also affect thiopurine-induced leukopenia in patients with IBD. To discuss thiopurine-induced leukopenia in more detail, investigation of SNPs in both exon 1 and exon 3 of NUDT15 is needed.

Azathioprine (AZA) is widely used to treat Crohn's disease (CD) with a recommended dose of 2-2.5 mg/kg per day for Westerners. Asian patients are suggested to take a lower dose. However, many clinicians reported poor efficacy with a reduced dose. This study aimed to explore a efficient and safe dose of AZA providing the best efficacy for Chinese CD patients.

Fifty patients with active CD were enrolled and randomized into two groups (n = 25 each). All other treatments were the same except that group A received 1 mg/kg per day and group B took 2 mg/kg per day of AZA. Complete remission (CR) rate and response rate at weeks 12, 24 and 48 were assessed by using intent-to-treat (ITT) and per-protocol (PP) analyses. Adverse events and recurrence rate were also evaluated.

At week 48, CR rate and response rate in group B (ITT: 50.0% and 59.1%; PP: 57.9% and 68.4%) were significantly higher than those in group A (ITT: 13.0% and 17.4%; PP: 16.7% and 22.2%) (P < 0.05). Nine adverse events occurred, including pancreatitis (n = 1), arthritis (n = 2) and myelosuppression (n = 6). There was no significant difference in adverse events between the two groups. However, recurrence rate was significantly higher in group A than in group B (P = 0.042).

AZA 2 mg/kg per day is more appropriate than 1 mg/kg per day for Chinese CD patients with a high efficacy, a low recurrence rate and not increased adverse events.

Thiopurines (azathioprine and mercaptopurine) are one of the immunosuppressive mainstays for the treatment of inflammatory bowel disease. In spite of its widespread use, thiopurine metabolism is still not fully understood, and a significant proportion of patients suffer toxicity or lack of efficacy. Different enzymatic pathways with individual variations constitute a pharmacogenetic model that seems to be suitable for monitoring and therapeutic intervention. This review is focused on current concepts and recent research that may help clinicians to rationally optimise thiopurine treatment in patients with inflammatory bowel disease.

It remains controversial whether 6-thioguanine nucleotide (6-TGN)-based dose adjusting can be beneficial in azathioprine (AZA) therapy. This study is designed to assess the role of 6-TGN concentrations in maintaining clinical remission in Chinese patients with Crohn's disease (CD).

We performed a prospective observational study and collected data of CD patients in the First Affiliated Hospital of Anhui Medical University from June 2013 to April 2014. Demographic material, CD activity index, 6-TGN concentration, and laboratory tests were recorded at baseline and at each visit. In addition, 6-TGN was measured when drug adverse effects occurred. All patients achieved maintenance stage were administered a stable AZA dose at least 3 months before enrollment and were followed up at least 12 months. Thiopurine S-methyltransferase (TPMT) genotype was measured before AZA treatment.

Sixty-nine patients receiving maintenance therapy were analyzed. A positive correlation was found between 6-TGN levels and AZA dose (r = 0.258, p = 0.032). The mean 6-TGN concentration was 302.06 ± 115.84 in the remission group vs. 264.94 ± 164.53 pmol/8 × 10(8) RBC in those with active disease (t = 0.847, p = 0.40), and 197.74 ± 66.54 pmol/8 × 10(8) RBC in patients who relapsed vs. 310.26 ± 122.38 pmol/8 × 10(8) RBC for those in sustained remission (t= -2.541, p = 0.013). In the leukopenia group, the 6-TGN concentration was 469.11 ± 115.53 pmol/8 × 10(8) RBC vs. 257.31 ± 83.74 pmol/8 × 10(8) RBC in the non-leukopenia group (t = 7.622, p < 0.001). There was a significant negative correlation between leukocyte count and 6-TGN concentration (r= -0.326, p = 0.006).

6-TGN measurement is a helpful method of preventing disease relapse and avoiding leukopenia in individual azathioprine maintenance therapy.

Thiopurines are commonly used drugs in inflammatory bowel disease. Intracellular levels of thiopurine metabolites [i.e. 6-thioguaninenucleotides (6-TGN)] are associated with efficacy and toxicity. Because 6-TGN measurement is not globally available, the mean corpuscular volume (MCV) has been proposed as a surrogate marker for monitoring thiopurine therapy.

To analyze the relationship between MCV and efficacy of thiopurines, defined as either response to therapy or 6-TGN levels.

A systematic search on PubMed was performed.

Fifteen studies were included. In six studies, a positive association was found between ΔMCV and 6-TGN. In four studies, it was suggested that ΔMCV can be used to predict clinical remission. In five articles, no association was found.

In the majority of articles, it was reported that ΔMCV is useful in guiding intracellular metabolite levels. However, there is insufficient evidence showing that ΔMCV can predict clinical remission.

Whether low-dose azathioprine (AZA) is effective in maintaining remission in patients with steroid-dependent ulcerative colitis (UC) remains unclear. We assessed the efficacy and safety of low-dose AZA in a Chinese population with UC.

We identified steroid-dependent UC patients in clinical remission on AZA maintenance therapy from a territory-wide IBD Registry. Standard- and low-dose AZA were defined as at least 2 mg/kg/day and less than 2 mg/kg/day, respectively. Relapse rates were analyzed by Kaplan-Meier analysis and compared using log-rank test.

Among 1226 UC patients, 128 (53% male, median duration on AZA 44 months) were included. Median maintenance AZA dose was 1.3 mg/kg/day. 97.7% of the patients were on concomitant oral 5-aminosalicylic acid. Cumulative relapse-free rates in patients on standard-dose and low-dose AZA were 71.2%, 52.8% and 45.2%, and 71.8%, 55.3% and 46.2% at 12, 24 and 36 months, respectively (p = 0.871). Relapse rate within 12 months was higher in patients who withdrew compared with those who maintained on AZA (52.6% versus 29.4%; p = 0.045). Mean corpuscular volume increased after AZA therapy in both of the low-dose [median (interquartile range, IQR): 88.2 (81.4-92.2) versus 95.1 (90.1-100.9) fl, p < 0.001] and standard-dose subgroups [median (IQR) 86.8 (76.9-89.9) versus 94.7 (85.9-99.7) fl, p < 0.001]. Leukopenia occurred in 21.1% of the patients. Patients on standard dose had a higher risk for leukopenia than those on low-dose AZA [odds ratio (OR) 3.9, 95% CI 1.9-8.2, p < 0.001].

In the Chinese population, low-dose AZA is effective for maintaining remission in steroid-dependent UC patients. Standard-dose AZA was associated with more than threefold increased risk of leukopenia.

The thiopurine drugs, 6-mercaptopurine and azathioprine, remain the mainstay of immunomodulator therapy for inflammatory bowel disease (IBD). Optimal management depends on achieving therapeutic levels of 6-thioguanine (6-TGN), but measuring thiopurine metabolites is associated with significant cost. Thiopurines cause lymphopenia and an increase in mean corpuscular volume (MCV). It is unclear whether any clinically useful correlation exists between 6-TGN levels and lymphocyte count or MCV.

The aim of this study is to investigate the correlation between 6-TGN levels and lymphocyte count and MCV in thiopurine-treated patients with IBD.

We analysed a prospectively acquired database of 67 patients with IBD treated with thiopurine therapy. The data were analysed looking at the relationship between 6-TGN levels and both lymphocyte count and MCV by using the Spearman's rank correlation coefficient.

Twenty-seven (40%) patients had therapeutic 6-TGN levels. Thirty-three (49%) patients had sub-therapeutic 6-TGN levels. A weak positive correlation between 6-TGN levels and lymphocyte count was demonstrated, but this was not statistically significant (Spearman's R = 0.14, P = 0.23). Spearman's rank correlation coefficient between 6-TGN levels and MCV was statistically significant (R = 0.42, P = 0.0005). MCV >101 fL excluded a subtherapeutic 6-TGN level with positive predictive value of 92%.

There is no specific lymphopenia that can be assumed to indicate a therapeutic 6-TGN level. The relationship between 6-TGN levels and MCV is likely to be clinically relevant. If MCV is elevated, 6-TGN is unlikely to be sub-therapeutic. MCV is a potential surrogate marker which can rule out sub-therapeutic thiopurine metabolites in patients with IBD treated with azathioprine or 6-mercaptopurine.

6-gingerol has been reported to have anti-inflammatory effects in different experimental settings. The present study aimed at evaluating the effect of 6-gingerol on dextran sodium sulfate (DSS)-induced barrier impairment and inflammation in vitro and in vivo.

a differentiated Caco-2 monolayer was exposed to DSS and treated with different concentrations of 6-gingerol (0, 1, 5, 10, 50, and 100 μM). Changes in intestinal barrier function were determined using transepithelial electrical resistance (TEER). The anti-inflammatory activity of 6-gingerol was examined as changes in the expression of proinflammatory cytokine using quantitative real-time PCR. Western blotting was employed to determine the activation of adenosine monophosphate-activated protein kinase (AMPK). Mice with DSS-induced colitis were given different oral dosages of 6-gingerol daily for 14 days. Body weight and colon inflammation were evaluated, and level of proinflammatory cytokines in colon tissues was measured.

6-gingerol treatment was shown to restore impaired intestinal barrier function and to suppress proinflammatory responses in DSS-treated Caco-2 monolayers. We found that AMPK was activated on 6-gingerol treatment in vitro. In animal studies, 6-gingerol significantly ameliorated DSS-induced colitis by restoration of body weight loss, reduction in intestinal bleeding, and prevention of colon length shortening. In addition, 6-gingerol suppressed DSS-elevated production of proinflammatory cytokines (IL-1β, TNFα, and IL-12).

our findings highlight the protective effects of 6-gingerol against DSS-induced colitis. We concluded that 6-gingerol exerts anti-inflammatory effects through AMPK activation. It is suggested that 6-gingerol has a promising role in treatment of IBD.

The use of thiopurines is well established in the management of inflammatory bowel disease. A wealth of data and experience, amassed over several decades, supporting their efficacy has recently been challenged by trials that failed to show a benefit in Crohn's disease when used early in the disease course, although other trials continue to support their role both as monotherapy and in combination with anti-TNF. Recent reports of previously unrecognized toxicity have also emerged. Fortunately, the absolute incidence of serious toxicity remains low, and an improved understanding of how best to minimize risk and the recognition of groups of patients at higher risk of toxicity from thiopurines means that they remain a relatively safe therapy in the majority of patients. In this paper, we review the literature evaluating the role of thiopurines in inflammatory bowel disease as well as their toxicity. We conclude that education regarding the spectrum of thiopurine side effects and optimal monitoring during therapy may help with optimizing safety and efficacy of these important medications.