Derivatives of 6-Nitrobenzimidazole Inhibit Fructose-Mediated Protein Glycation and Intracellular Reactive Oxygen Species Production

Visnagin: A novel cardioprotective agent against anthracycline toxicity (Review)

Doxorubicin (DOX), a cornerstone of cancer chemotherapy, is marred by its dose-dependent cardiotoxicity, leading to cardiomyopathy and heart failure. The epidemiology of DOX-related cardiotoxicity highlights its cumulative, progressive nature, with a significant impact on the health of patients. The pathophysiological mechanisms involve mitochondrial dysfunction, oxidative stress and disrupted calcium homeostasis in cardiomyocytes. Despite the search for effective cardioprotective strategies, current treatments offer limited efficacy. Visnagin emerges as a potential solution, known for its vasodilatory and anti-inflammatory properties, and recent studies suggest its cardioprotective efficacy against DOX-induced cardiotoxicity through mitochondrial protection, the modulation of key signaling pathways and the inhibition of apoptosis. The present review aimed to provide a comprehensive overview of the mechanisms of action of visnagin, as well as to provide experimental evidence, and potential integration into cancer treatment regimens, highlighting its promise as a novel therapeutic agent for managing cardiotoxicity in patients undergoing anthracycline chemotherapy.

Inhibition of Advanced Glycation End-Products by Tamarindus indica and Mitragyna inermis Extracts and Effects on Human Hepatocyte and Fibroblast Viability

Tamarindus indica and Mitragyna inermis are widely used by herbalists to cure diabetes mellitus. The aim of this study is to investigate the inhibitory potential of aqueous and various organic solvent fractions from both plants and some isolated compounds against advanced glycation end-products (AGEs). For this purpose, an in vitro BSA-fructose glycation model was used to evaluate the inhibition of AGE formation. Furthermore, the effects of the fractions on mouse fibroblast (NIH-3T3) and human hepatocyte (HepG2) survival were evaluated. The leaf, stem, and root fractions of both plants exhibited significant inhibition of AGEs formation. The IC₅₀ values appeared to be less than 250 µg/mL; however, all fractions presented no adverse effects on NIH-3T3 up to 500 µg/mL. Otherwise, our phytochemical investigation afforded the isolation of a secoiridoid from the Mitragyna genus named secoiridoid glucoside sweroside (1), along with three known quinovic acid glycosides: quinovic acid-3β-O-β-d-glucopyranoside (2), quinovic acid-3-O-β-d-6-deoxy-glucopyranoside, 28-O-β-d-glucopyranosyl ester (3), and quinovic acid 3-O-α-l-rhamnopyranosyl-(4→1)-β-d-glucopyranoside (4). In particular, 1-3 are compounds which have not previously been described in Mitragyna inermis roots. However, the isolated compounds did not exhibit AGE inhibitory activity. Further investigation on these potent antiglycation fractions may allow for the isolation of new antidiabetic drug candidates.

Visnagin ameliorates myocardial ischemia/reperfusion injury through the promotion of autophagy and the inhibition of apoptosis

Visnagin is a furanochromone and one of the main compounds of Ammi visnaga L. that had been used to treat nephrolithiasis in Ancient Egypt. Nowadays, visnagin was widely used to treat angina pectoris, urolithiasis and hypertriglyceridemia. The potential mechanisms of visnagin involved in inflammation and cardiovascular disease were also identified. But the protective effect of visnagin on myocardial ischemia/reperfusion injury has not been confirmed. Our aim was, for the first time, to investigate the potential protective effect of visnagin on cardiac function after myocardial ischemia-reperfusion injury in a rat model, and to identify its underlying mechanism involving the inhibition of apoptosis and induction of autophagy. Thirty SD rats were randomly divided into sham group, ischemia/reperfusion group (IR), ischemia/reperfusion with visnagin (IR + visnagin) group. Myocardial ischemia/Reperfusion injury model was established. Hemodynamic measurements and echocardiography were used to analyze cardiac function, TUNEL staining and caspase activity, LC3 dots were detected with immunofluorescence staining, LC3 expression was evaluated by western blot analysis, transmission electron microscopy (TEM) was used to detect autophagosomes. Compared with the sham group and visnagin group, the cardiac dysfunction, LC3II, autophagy flow in the IR+ visnagin group increased significantly (P<0.01), but the activity of caspase-3 and caspase-9 and the apoptotic in the IR + visnagin group decreased significantly (P<0.01). In conclusion, visnagin may play a protective role in ischemia/reperfusion injury by inducing autophagy and reducing apoptosis.

The anticancer activity of visnagin, isolated from Ammi visnaga L., against the human malignant melanoma cell lines, HT 144

Melanoma is a cancer of melanocyte cells and has the highest global incidence. There is a need to develop new drugs for the treatment of this deadly cancer, which is resistant to currently used treatment modalities. We investigated the anticancer activity of visnagin, a natural furanochromone derivative, isolated from Ammi visnaga L., against malignant melanoma (HT 144) cell lines. The singlet oxygen production capacity of visnagin was determined by the RNO bleaching method while cytotoxic activity by the MTT assay. Further, HT 144 cells treated with visnagin were also exposed to visible light (λ ≥ 400 nm) for 25 min to examine the illumination cytotoxic activity. The apoptosis was measured by flow cytometry with annexin V/PI dual staining technique. The effect of TNF-α secretion on apoptosis was also investigated. In standard MTT assay, visnagin (100 µg/mL) exhibited 80.93% inhibitory activity against HT 144 cancer cell lines, while in illuminated MTT assay at same concentration it showed lesser inhibitory activity (63.19%). Visnagin was induced apoptosis due to the intracellular generation of reactive oxygen species (ROS) and showed an apoptotic effect against HT 144 cell lines by 25.88%. However, it has no effect on TNF-α secretion. Our study indicates that visnagin can inhibit the proliferation of malignant melanoma, apparently by inducing the intracellular oxidative stress.