Over the recent years, numerous research efforts have been focused toward xanthones, a class of heterocyclic compounds characterized by a three-ring core structure and a diverse range of biological activities. Despite extensive studies, no xanthone-based molecule has successfully progressed through clinical trials to reach pharmaceutical applications. Xanthones belong to the class of secondary metabolites that exist naturally, found in various plant species, and their structural diversity has been further expanded through synthetic modifications to enhance their pharmacological efficacy. This review provides a comprehensive description of the therapeutic potential of xanthone derivatives within the scope of neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, multiple sclerosis, and neuroinflammation. Existing literature has been rigorously examined to highlight the pharmacological relevance of xanthones in these disorders. Additionally, the pathophysiological aspects of each disease are discussed in detail to establish a mechanistic understanding of how xanthone derivatives may exert neuroprotective effects. Furthermore, the SAR of xanthones is explored to elucidate key molecular features responsible for their bioactivity, providing insights into rational drug design. By synthesizing and critically analyzing the existing research, this review is focused in highlighting the therapeutic relevance of xanthones in neurodegenerative diseases and their potential as lead candidates for further drug development.

The increase in the incidence of gastric ulcer (GU) has posed major threat on public health. This research aimed to evaluate gastroprotective properties of the aqueous leaf extract of Talium triangulare (AETT) in ethanol-induced gastric ulceration. GU was induced via oral administration of single dose of 5 mLkg-1 of 90% ethanol in rats and protection of 200 mgkg-1 bw of AETT and 20 mgkg-1 bw of omeprazole was investigated for 14 d via oral treatment. Influence of AETT on anti-inflammatory, redox assays, ulcer index (UI), and gastric mucosa histological alterations were evaluated. Significant increase in myeloperoxidase (MPO) and tumor necrosis factor-alpha levels compared to untreated group established gastric inflammation in rats induced by ethanol. Gastric ulcerated group exhibited heightened oxidative stress with concurrent decline in activities of antioxidant enzymes. Ethanol exposure to rats resulted in induction of lipid peroxidation, prominently elevating gastric malondialdehyde (MDA) concentration. Nevertheless, treatment with AETT or omeprazole exhibited substantial anti-inflammatory effects within gastric mucosa by attenuating expression of markers associated with inflammation. AETT demonstrated reduction in concentrations of MDA and H2O2, thereby alleviating progression of lipid peroxidation cascades. Also, AETT exhibited mitigating effect on ethanol-induced oxidative harm by enhancing the functionality of protective enzymes and elevating glutathione (GSH) concentration. Overall, AETT exhibited enhancements in activities of cytoprotective antioxidant enzymes, mitigated impact of oxidative stress and inflammation, inhibited lipid peroxidation, and decreased UI score. These beneficial effects could be attributed to phytochemicals present in AETT including 6,10,14-trimethyl-2-pentadecanone and Phytol. Outcome of this study established the traditional herbal claims of AETT.

Tangeretin, a flavone compound (O-polymethoxylated) naturally present in tangerine and other citrus peels has demonstrated effectiveness as an anti-inflammatory and neuroprotective agent in several disease model. This study evaluated the impact of tangeretin in mitigating cognitive dysfunction and oxidative stress induced by colchicine in rats, comparing its efficacy with donepezil hydrochloride.

Cognitive dysfunction was induced by administering colchicine (15 µg/rat) intracerebroventricularly (ICV) via a stereotaxic apparatus in male Wistar rats. Colchicine resulted in poor memory retention in acquiring and retaining a spatial navigation task, passive avoidance apparatus, and Morris water maze paradigms. Chronic treatment with tangeretin (at doses of 50, 100, and 200 mg/kg, p.o. once daily) and donepezil hydrochloride (at a dose of 10 mg/kg, p.o. daily) for 28 days, starting seven days before colchicine injection, significantly ameliorated colchicine-induced cognitive impairment.

The biochemical analysis showed that chronic administration of tangeretin effectively reversed the colchicine-induced increase in the level/activity of lipid peroxidation, hydrogen peroxide (H2O2), myeloperoxidase (MPO), nitrite, reactive oxygen species (ROS), tumour necrosis factor-α (TNF-α), nuclear factor kappa B (NF-κB), interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-10 (IL-10), serotonin, dopamine, glutamate, amyloid beta (Aβ) peptide, and caspase-3. Tangeretin also reversed the colchicine-induced reduction in the level/activity of brain-derived neurotrophic factor (BDNF), amma-aminobutyric acid (GABA), acetylcholinesterase (AChE), glutathione S-Transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH), and total thiol (T-SH) in rat brains. However, donepezil hydrochloride did not prevent oxidative stress.

These findings suggest that chronic administration of tangeretin at 50, 100, and 200 mg/kg, p.o. once daily, was protective in mitigating colchicine-induced cognitive impairment and associated oxidative stress. At the same time, donepezil hydrochloride did not demonstrate similar effects.

The present study evaluated the effects of ginger and bitterleaf tea infusions on redox and inflammatory balance in rats. Twenty-four Wistar rats with weights of between 160 and 180 g were assigned into four (4) groups (n = 6). The control group received distilled water, while the remaining groups were administered tea infusions of ginger, bitterleaf, or a combination of both at 5 mg/mL, respectively. Bitterleaf and ginger teas elevated the levels of superoxide dismutase, catalase, glutathione peroxidase, and reduced glutathione in rat plasma and liver, while malondialdehyde levels decreased. Furthermore, ginger tea caused an increase in the expression of nuclear factor erythroid-2-related factor 2 (Nrf-2) and reduced tumor necrosis factor alpha (TNF-α). The GC-MS analysis of the teas identified 77 chemical compounds, among which gingerol and precocene I were predominant. Collectively, the findings indicate, in particular, that ginger tea may boost antioxidant and anti-inflammatory capacity by increasing Nrf-2 levels.

Vernonia amygdalina (VA) leaves contain many potential active ingredients and exhibit diverse pharmacological activities. The antihypertensive, anti-inflammatory, and analgesic effects of VA crude and fraction extracts were carried out using Swiss albino mice models. VAE is considered safe to be administered due to LD50 being greater than 10,000 mg/kg body weight. A dose-dependent increase in antihypertensive, anti-inflammatory, and analgesic activities was observed in both VAE and fractions, similar to the reference drugs. The antihypertensive effect of the VAE 2.0 (2000 mg/kg, SBP: ↓26.05 %, DBP: ↓34.51 %) was nearly equivalent to Captopril (100 mg/kg, SBP: ↓30.28 %, DBP: ↓40.71 %) with no statistically significant difference (p > 0.05). The VAE 1.0 (1000 mg/kg), and EA 30 (30 mg/kg) showed potent anti-inflammatory activity when reducing the total edematous paw volume significantly (p < 0.01) by ↓65.58 %, and ↓69.34 %, respectively, similar to Ibuprofen (7.5 mg/kg, ↓67.03 %). Besides, VAE (>500 mg/kg), and W 400 (water, 400 mg/kg) fraction extracts showed a potent analgesic effect equivalent to Para 50 (paracetamol 50 mg/kg) for the highest protection (>65 %) against the acetic acid-induced writhing after 35 min. Moreover, cepharanthine, cynaroside, and vernoniosides of VA leaf extract exhibited the highest affinity (>10 kcal/mol) in anti-inflammatory and analgesic targets (iNOS and COX-2) and antihypertensive targets (ACE and β1 adrenoreceptor). Therefore, the crude and fraction extracts of VA leaves from the percolation method and bioactive metabolites are a potential source that can be developed into antihypertensive, anti-inflammatory, and analgesic agents in herbal medicine.

Naja nigricollis Venom (NnV) contains complex toxins that affects various vital systems functions after envenoming. The venom toxins have been reported to induce male reproductive disorders in envenomed rats. This present study explored the ameliorative potential of kaempferol on NnV-induced male reproductive toxicity. Fifty male wistar rats were sorted randomly into five groups (n = 10) for this study. Group 1 were noted as the control, while rats in groups 2 to 5 were injected with LD50 of NnV (1.0 mg/kg bw; i.p.). Group 2 was left untreated post envenomation while group 3 was treated with 0.2 ml of polyvalent antivenom. Groups 4 and 5 were treated with 4 and 8 mg/kg of kaempferol, respectively. NnV caused substantial reduction in concentrations of follicle stimulating hormone, testosterone and luteinizing hormone, while sperm motility, volume and counts significantly (p < 0.05) decreased in envenomed untreated rats. The venom enhanced malondialdehyde levels and substantially decreased glutathione levels, superoxide dismutase and glutathione peroxidase activities in the testes and epididymis of envenomed untreated rats. Additionally, epididymal and testicular myeloperoxidase activity and nitric oxide levels were elevated which substantiated severe morphological defects noticed in the reproductive organs. However, treatment of envenomed rats with kaempferol normalized the reproductive hormones with significant improvement on sperm functional parameters. Elevated inflammatory and oxidative stress biomarkers in testis and epididymis were suppressed post kaempferol treatment. Severe histopathological lesions in the epididymal and testicular tissues were ameliorated in the envenomed treated groups. Results highlights the significance of kaempferol in mitigating reproductive toxicity induced after snakebite envenoming.

Vernonia amygdalina (VA) is a plant that consumed as vegetable by Indonesians contained numerous secondary metabolites. VA's pharmacological action, including its antioxidant properties, anticancer, antidiabetic, and hepatoprotective. The purpose of this research is to reveal the activity of Vernonia amygdalina. leafs aqueous fraction (VALAF) as a blood pressure-lowering agent in hypertensive model.

Combination of prednisone and NaCl were used as hypertensive inducer. The animals were split into five different groups, normal control group treated with distilled water, treatment VALAF groups with dose of 10; 20 and 40 mg/kg BW respectively, while the last group was treated with captopril at dose of 2.25 mg/kg BW. All animals were given an oral treatment for 15 days. On days 5, 10, and 15, systolic and diastolic blood pressure, heart rate (HR), mean arterial pressure (MAP), and blood flow (BF) were all measured. On days 0 and 15, NO level were assessed. All data were analyzed using two-way ANOVA, and Duncan Multiple Range Test.

The V. amygdalina leaf aqueous fraction has blood pressure lowering activity. The blood pressure parameter of the rats treated with VALAF were lower as compared to the normal control group (p<0.05). NO levels in the VALAF group were not significantly higher than in the normal control group (p>0.05). The VALAF 20 give the greatest percentage of decrease in blood pressure, heart rate and blood volume on the 15th day of examination.

These study indicated that V. amygdalina leaf aqueous fraction has the potential to be an alternative therapy for managing blood pressure in hypertensive animal models.

Storage proteins from Sphenostylis stenocarpa and Phaseolus lunatus were fractionated, and their in vitro bioactivities were investigated. Albumin, globulin, prolamin, and glutelin constituents of the respective seeds were successively fractionated using the modified Osborne method. Phenylmethylsulfonyl fluoride (1 mM) was used as a protease inhibitor. The antioxidant, anti-inflammatory, and acetylcholinesterase-inhibitory activities of the protein fractions were evaluated using different appropriate techniques. Globulin was the predominant fraction, with a yield of 43.21±0.01% and 48.19±0.03% for S. stenocarpa and P. lunatus, respectively, whereas prolamin was not detected in both seeds. The protein fraction markedly scavenges hydroxyl radicals, nitric oxide radicals, and 2,2-diphenyl-1-picryldydrazyl radicals with concomitant high free radical-reducing power. Albumin and globulin fractions elicited the highest acetylcholinesterase-inhibitory potential of 48.75% and 49.75%, respectively, indicating their great application potential in managing neurodegenerative diseases. In this study, the albumin, globulin, and glutelin fractions of these underutilized legumes showed great analeptic bioactivities, which could be utilized as health-promoting dietary supplements/products.

The whole world is still challenged with COVID-19 pandemic caused by Coronavirus-2 (SARS-CoV-2) which has affected millions of individuals around the globe. Although there are prophylactic vaccines being used, till now, there is ongoing research into discovery of drug candidates for total eradication of all types of coronaviruses. In this context, this study sought to investigate the inhibitory effects of six selected tropical plants against four pathogenic proteins of Coronavirus-2. The medicinal plants used in this study were selected based on their traditional applications in herbal medicine to treat COVID-19 and related symptoms. The biological activities (antioxidant, free radical scavenging, and anti-inflammatory activities) of the extracts of the plants were assessed using different standard procedures. The phytochemicals present in the extracts were identified using GCMS and further screened via in silico molecular docking. The data from this study demonstrated that the phytochemicals of the selected tropical medicinal plants displayed substantial binding affinity to the binding pockets of the four main pathogenic proteins of Coronavirus-2 indicating them as putative inhibitors of Coronavirus-2 and as potential anti-coronavirus drug candidates. The reaction between these phytocompounds and proteins of Coronavirus-2 could alter the pathophysiology of COVID-19, thus mitigating its pathogenic reactions/activities. In conclusion, phytocompounds of these plants exhibited promising binding efficiency with target proteins of SARS-COV-2. Nevertheless, in vitro and in vivo studies are important to potentiate these findings. Other drug techniques or models are vital to elucidate their compatibility and usage as adjuvants in vaccine development against the highly contagious COVID-19 infection.

The study investigated the effects of Zingiber officinale root and Vernonia amygdalina leaf on the brain redox status of Wistar rats. Twenty-four (24) rats weighing 160 ± 20 g were randomly assigned into four (4) groups, each with six (6) rats. Animals in Group 1 (control) were orally administered distilled water (1 mL), while the test groups were orally administered 5 mg/mL of either Z. officinale, V. amygdalina infusion, or a combination of both, respectively, for 7 days. The rats were sacrificed at the end of treatments and blood and tissue were harvested and prepared for biochemical assays. Results showed that administration of V. amygdalina and Z. officinale, as well as their coadministration, reduced the levels of malondialdehyde (MDA), nitric oxide (NO), acetylcholinesterase (AChE), and myeloperoxidase (MPO) in rat brain tissue compared with the control group. Conversely, coadministration of V. amygdalina and Z. officinale increased the levels of reduced glutathione (GSH) in rat brain tissue compared with the control group. However, the administration of the infusions singly, as well as the combination of both infusions, did not have any effect on the rat brain levels of glutathione peroxidase (GPx) and catalase (CAT) antioxidant enzymes compared to the control. Taken together, the findings indicate that the V. amygdalina and Z. officinale tea infusions have favorable antioxidant properties in the rat brain. The findings are confirmatory and contribute to deepening our understanding of the health-promoting effects of V. amygdalina and Z. officinale tea infusions.

Ulcerative colitis (UC), a subcategory of inflammatory bowel diseases, affects more than 2 million people globally. This study sought to investigate the curative ability of aqueous leaf extract of Telfairia occidentalis (ATO) on dextran sodium sulfate (DSS)-mediated colitis in rats. UC was induced by 5% of DSS in drinking water, and the curative ability of ATO was assessed at 200 mg/kg by oral administration for 10 days. The effect of ATO was deduced on anti-inflammatory, preclinical features [disease activity index (DAI)], redox assays, and alterations both microscopic and macroscopic of the colonic mucosa. DSS mediated inflammation in colons of rats with a significant increase in nitric oxide, myeloperoxidase, IL-1β, IL-6, and TNF-α levels compared with a control group. Lipid peroxidation was also induced following exposure of rats to DSS. There is a marked decrease in antioxidant enzymes activities in DSS group. However, treatment with ATO markedly inhibited the colonic inflammation by reversing the elevated levels of inflammatory markers. Furthermore, ATO suppressed the lipid peroxidation chain reaction by reducing the level of malondialdehyde and hydrogen peroxide. ATO attenuates DSS-induced oxidative stress by increase the level of GSH and enhancing the activities of the cytoprotective enzymes (catalase, glutathione-S-transferase, and superoxide dismutase). Taken together, ATO reduced DAI score, inhibited inflammation, suppressed lipid peroxidation, attenuated oxidative stress, and enhanced the antioxidant enzymes activities. These therapeutic effects of ATO might be due to its phytochemicals as showed in gas chromatography-mass spectroscopy results. The findings of this study indicate that aqueous leaf extract of T. occidentalis has could be a drug candidate for the treatment of UC. PRACTICAL APPLICATIONS: The study focused on the curative ability of aqueous leaf extract of Telfairia occidentalis on dextran sodium sulfate (DSS) mediated colitis in rats. The extract elicits beneficial effects against colitis via its ability to reduce mucosal inflammation, suppress lipid peroxidation, attenuate oxidative stress, enhance the antioxidant enzymes activities, and reduce both infiltration of inflammatory cells and mucosal damage in colon. This study provides scientific evidence to the therapeutic ability of aqueous leaf extract of T. occidentalis in the treatment of DSS-induced ulcerative colitis and could be a drug candidate for the treatment of inflammatory bowel diseases in humans.