Antioxidant activity of a new multiflorane-type triterpene from seeds of Cucurbita Argyrosperma and their protective role on hydrogen peroxide induced oxidative stress
Pérez Gutiérrez, Rosa Martha
Muñiz Ramirez, Alethia
Mota Flores, José María
García Campoy, Abraham Heriberto
"Background: Cucurbita Argyrosperma seeds have acquired a reputation as an herbal remedy to treat various diseases because this plant is a predominant source of natural compounds with potent anti-inflammatory, antioxidant properties, and seed supplementation improves oxidative stress. Previous studies indicated that an imbalance between H2O2 production and elimination capacity is responsible for β-cell vulnerability, making β-cell a target susceptible to pathological disasters. This investigation aimed to evaluate the protective effects of one new multiflorane-type triterpene 3β-trans-caffeoyloxymultiflor-8-ene- 7α,12β, 18 β-triol (1) from MeOH extract from C. Argyrosperma, on rat pancreatic β cells (INS-1 cells) exposed to hydrogen peroxide (H2O2) induced oxidative stress conditions. Methods: The chemical structure of the novel triterpene, which was identified as 3β-trans-caffeoyloxymultiflor-8-ene- 7α,12β, 18 β-triol (1), was established based on the interpretation of spectroscopic analyses. The antioxidant activities of 1 were leaded by detect radical scavenging potential of 2,2-dyphenyl-1-picrylhydrazyl (DPPH) and 3.1 2,2′-Azino-bis(3-Ethylbenzothiazoline-6-Sulfonic Acid) ABTS. The assays were conducted on INS-1 cells line exposed to increasing concentrations of 1 at 5,10 and 20 µg/mL and H2O2 at 250 µM. Then, the experiments, cell viability, cell integrity ((LDH; lactate dehydrogenase release), mitochondrial function (ATP analysis), ROS formation, lipid peroxidation (MDA) and caspase-3, 9 activities were measured in the cells. We also determined the effect of 1 on antioxidant enzyme levels and cytotoxicity in pancreatic β cells under oxidant conditions. Results: The results showed that triterpene displayed high free-radical-scavenging activity, which is similar to that of standard antioxidants used. At concentrations of 5, 10, and 20 𝜇g/mL protect INS-1 cells against H2O2 induced cytotoxicity decrease in cell death, with a marked increase in cell viability, sustained cellular functionality (ATP). Antioxidant enzymes such as glutathione peroxidase (GPx), glutathione reduced (GSH), catalase (CAT), superoxide dismutase (SOD), and the non-antioxidant enzyme (GSH) increased in INS-1 cells with 1 pretreatment. MDA in pancreatic cells was ameliorated by 1 pretreatment reducing intracellular reactive oxygen species level. Findings also demonstrated that H2O2-induced apoptosis in INS-1 cells and produced modulation of the caspase-3, 9 expressions in INS-1 cells exposed to 1. Exposure to 1significantly inhibited ROS and apoptosis production, reducing β cell dysfunction under oxidant conditions. Conclusions: Triterpene consequently could be a promising natural antioxidant for use in maintaining the integrity of pancreatic β-cells exposed to oxidative stress conditions being able to participate in the control type 2 diabetes."
Knowledge areaBIOLOGÍA VEGETAL (BOTÁNICA)
PublisherFunctional Food Center Inc.
Free radical scavenging