Antioxidant and anti-inflammatory activities of Ganoderma resinaceum (Boud) fruiting bodies extracts

Abstract

Introduction: Ganoderma resinaceum is used to treat oxidative and inflammatory-related diseases such as cardiovascular and liver diseases. Thus, this study aimed to evaluate the antioxidant and anti-inflammatory activities of different extracts from G. resinaceum fruiting bodies. Methods: Aqueous crude (GRT), mycelial (MYC), exopolysaccharide (EPS I, EPS II) and water-soluble polysaccharide-rich (GRP I and GRP II) extracts of G. resinaceum were assessed for their free radical scavenging and metal chelating ions assays. The in vitro anti-inflammatory activity was evaluated by stabilization of erythrocytes’ membranes and protein denaturation assays. For the in vivo study, paw oedema was induced by administration of κ-carrageenan (0.1 mL; 1%) to male Wistar rats aged 4 to 6 weeks. Animals were pre-treated with G. resinaceum extracts (125 mg/kg) and diclofenac sodium (20 mg/kg). Inflammatory cytokine and chemokine levels were determined, and histological analysis of paw tissue was performed. Results: G. resinaceum polysaccharide-rich extracts (GRP I and GRP II) showed the best bioactivities. They scavenged DPPH (1,1-diphenyl-2-picrylhydrazyl, ABTS (2,2-azino-bis-3- ethylbenzylthiazoline-6-sulfonic acid, and NO (nitric oxide) radicals, and chelated ferrous ions, stabilized murine erythrocyte membranes, and inhibited protein denaturation. At 125 mg/kg, GRP I and GRP II restored the microarchitecture with a weak infiltration of immune cells in the subcutaneous tissues. Moreover, they decreased the overproduction of proinflammatory cytokines growth colony-stimulating factor (G-CSF), interferon gamma (IFNγ), tumour necrosis factor alpha (TNFα), chemokines (eotaxin, fractalkine) and increased the levels of anti-inflammatory cytokines (IL-10, IL-12p70). Conclusion: G. resinaceum polysaccharide extracts could be potent antioxidant and antiinflammatory agents.