Saponins are triterpenoid or steroidal glycosides and are an important group of naturally occurring compounds of plant origin. They exhibit diverse pharmacological potentials including radical scavenging, as well as neuroprotective, anti-diabetic and anti-inflammatory activities, owing to their diverse chemical scaffolds. Saponins consist of an aglycone part (non-sugar) and a glycone part (sugar) and have at least one glycosidic (C–O sugar bond) linkage present between the glycone and aglycone mostly at C-3. On the basis of the aglycone part, saponins are classified into triterpenoid glycosides, steroid glycosides and alkaloid glycosides. Saponins exhibit neuroprotective activities against various disorders of the central nervous system (CNS) including stroke, Alzheimer’s disease (AD), Huntington’s disease (HD) and Parkinson’s disease (PD). They mediate their therapeutic effects by modulation of various pathological targets. This study highlights various neuroprotective mechanisms of saponins including free radical scavenging, modulation of neuroprotective signaling pathways, activation of neurotrophic factors, modulation of neurotransmitters, inhibition of BACE1 enzyme and tau hyper-phosphorylation. The study concludes that saponins have considerable efficacy against various pathological targets of neurological disorders, especially AD, and might be an important source of leads against neurodegenerative disorders.
Objective. (−) Epicatechin (EP) is a naturally occurring antioxidant flavonoid found in some green plants. The current study was designed to evaluate the potential role of antioxidant mechanisms in the hepatoprotective properties of EP using the carbon tetrachloride (CCl4)-induced acute liver injury model. Materials and Methods. Rats (n = 7 per group) were divided into five groups including control group, (−) epicatechin group (20 mg·kg−1 body weight), CCl4 group (1 mL−1 body weight), CCl4-EP treatment group, and CCl4-silymarin (SILY) group. The levels of enzymes including hepatic malondialdehyde (MDA), glutathione (GSH), catalase (CAT), glutathione S-transferase (GST), nitric oxide synthase (NOS), glutathione peroxidase (GPx), and cytochrome P450 (CYP450) were analyzed via enzyme-linked immunosorbent assay (ELISA). Histological studies were performed on all groups to assess the regenerative effects of test sample and compare it with the control group. Results. Test compound EP and standard drug silymarin (SILY) considerably reduced liver function enzyme levels in the blood, which were raised by CCl4 administration, and increased serum albumin and total protein (TP) concentrations. The hepatic malondialdehyde (MDA) level was considerably declined, whereas glutathione (GSH), catalase (CAT), glutathione S-transferase (GST), nitric oxide synthase (NOS), glutathione peroxidase (GPx), and cytochrome P450 (CYP450) levels were upregulated in the EC-treated groups. The hepatoprotective results of the study were further confirmed via the histological assessments, which indicated a regeneration of the damaged hepatic tissue in treated rats. Conclusions. The results of this study revealed a significant protective efficacy of EP against CCl4-induced liver injury, which was potentially mediated via upregulation of antioxidant enzymes and direct scavenging effects of the compound against free radicals.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.