Influence of ultrasound on Pleurotus pulmonarius (Fr.) Quél. (Grey Oyster Mushroom) – Protective Effects Against Metabolic Syndrome in Rats Fed with a High-fat Diet

The Pleurotus pulmonarius (Fr.) Quel. (Grey Oyster mushroom) is one of the most widely consumed mushroom species worldwide, and it possesses various medicinal properties. The application of ultrasound resulted in P. pulmonarius extracts with improved bioactivities both in cellular and animal models. However, no studies have investigated the preventive effects of ultrasound extract of P. pulmonarius in animal models. In this study, Wistar-Kyoto rats were pre-treated with the ultrasound extract of P. pulmonarius at high (500 mg/kg bw) and low (200 mg/kg bw) doses for 15 days. The rats were subsequently fed with a high-fat diet (HFD) for another 15 days. Rats pre-treated with P. pulmonarius extract from a high-dose ultrasound showed lower levels of serum cholesterol (1.50 mmol/L), triglyceride (0.60 mmol/L), and LDL (0.29 mmol/L). These rats also had lower oxidative stress, with MDA levels of only 10.81 µg/mg protein. The ultrasound extract of P. pulmonarius also exhibited anti-hyperglycaemic effects, whereby rats had lower blood glucose levels. Rats pre-treated with the ultrasound extract of P. pulmonarius also had inhibited inflammatory biomarkers CREB1 (2.85 pmol/mL), NF-κB2 (0.81 ng/mL), and STAT3 (0.48 ng/mL), proving the anti-inflammatory activity of the ultrasound extract. This study is the first to show the ability of P. pulmonarius extract prepared using ultrasound to prevent developing metabolic syndrome such as hyperlipidaemia, hyperglycaemia, oxidative stress, and inflammation in rats fed with HFD.