Glycyrrhizic acid (GA) inhibits reactive oxygen Species mediated photodamage by blocking ER stress and MAPK pathway in UV-B irradiated human skin fibroblasts.

Background: Previously we have reported that generation of reactive oxygen species is the prime event responsible for calcium mediated activation of PERK-eIF2α-CHOP pathway and apoptosis in UV-B irradiated human skin fibroblasts (Hs68). We have also reported that glycyrrhizic acid (GA) mediates potent photoprotective activity against UV-B - irradiation-induced photodamage in human skin fibroblast.

Objective: In the present study, we aimed to investigate the role of GA in preventing oxidative stress mediated unfolded protein response (UPR) and mitogen activated protein kinases (MAPK) pathway.

Oxidative stress mediated Ca(2+) release manifests endoplasmic reticulum stress leading to unfolded protein response in UV-B irradiated human skin cells.

Background: Exposure of skin to ultraviolet (UV) radiation, an environmental stressor induces number of adverse biological effects (photodamage), including cancer. The damage induced by UV-irradiation in skin cells is initiated by the photochemical generation of reactive oxygen species (ROS) and induction of endoplasmic reticulum (ER) stress and consequent activation of unfolded protein response (UPR).

Objective: To decipher cellular and molecular events responsible for UV-B mediated ER stress and UPR activation in skin cells.

A validated high-performance thin-layer chromatography method for the identification and simultaneous quantification of six markers from Platanus orientalis and their cytotoxic profiles against skin cancer cell lines.

Betulinic acid (1), betulinic acid-3-acetate (2), 3-acetylbetulinaldehyde (3), oleanolic acid-3-acetate (4), 3-β-hydroxy-28,19-β-olenolide (5), and β-sitosterol (6) were isolated from Platanus orientalis and a high-performance thin-layer chromatography method was developed for their simultaneous quantification. The markers were first derivatized on the chromatogram with ceric ammonium sulfate and then high-performance thin-layer chromatography densitometry was carried out. Chromatographic separation of these markers was carried out on silica gel 60 plates using a ternary solvent system n-hexane/toluene/acetone (6:3.

Effect of N-acetyl cysteine (NAC), an organosulfur compound from Allium plants, on experimentally induced hepatic prefibrogenic events in Wistar rat.

Aim of present study was to investigate the effect of NAC on experimental chronic hepatotoxicity models induced by carbon tetrachloride (CCl₄) and thioacetamide (TAA). CCl₄ toxicity was induced by administering 200 μl CCl₄ (diluted 2:3 in coconut oil)/100 g body weight, p.o.