Inducible Nitric Oxide Synthase Downregulation and Apoptotic Activity of Pleurotus florida (Oyster Mushroom)

Background: Pleurotus florida is an edible delicious mushroom grown on large scale in different parts of the world. Objective: The objective of this study is to test the hepatoprotective, cytotoxic, and apoptotic activities of methanol extract of P. florida. Materials and Methods: 1.5 µg lipopolysaccharide (LPS)/25 g body weight was used to induce hepatic inflammation in Baggs albino mice strain c followed by treatment with varied concentrations of P. florida methanol extract. Hepatoprotective activity of mushroom extract was studied examining the liver sections. Total RNA of hepatocytes was isolated and reverse transcriptase‑polymerase chain reaction (RT‑PCR) of inducible nitric oxide synthase (iNOS) gene was performed. The mushroom extract was evaluated for its cytotoxic and apoptotic activity against human cervical carcinoma cells using 3‑(4,5‑dimethylthiazol‑2yl)‑2,5‑diphenyl tetrazolium bromide and 4’‑6‑diamidino‑2‑phenylindole assay, propidium iodide, acridine orange/ ethidium bromide staining methods. Results: High hepatoprotection with no abnormalities was observed at 125 µg of mushroom extract. RT‑PCR showed significantly reduced transcriptional expression of iNOS at 125 µg concentration of mushroom extract. The methanol extract of P. florida showed cytotoxic activity with IC50 of 47.11 ± 0.01 μg/mL and effectively induced apoptosis in a concentration‑dependent manner. Conclusion: The results of the present study revealed that P. florida is not only a nutritionally valuable food but also an important source for therapeutic compounds.