In vivo antioxidant properties of Cotinus coggygria extracts

Abstract

The Smoke tree (Cotinus coggygria Scop.), well known as poisonous plant, is used mainly externally by the Balkan folk medicine for its antiseptic and anti-inflammatory properties. The aim of our study was to Ðµxplore the effect of aqueous infusion from C. coggygria leaves (AICCL) and ethanol infusion of C. coggygria heartwood (EICCW) in two experimental models of oxidative stress: Paracetamol (P)-induced liver toxicity (PILT) and Indomethacin (IN)-induced gastric ulcerogenesis (INIGU). Additional aim was to identify and extract the major phytochemical components of both infusions by Ultrahigh-Performance Liquid Chromatography coupled with Time-of-Flight mass spectrometry analyzer (ToF/MS) with an Electro Spray Ionization (ESI) source (UPLC-ESI/ToF/MS), as well as by High-Performance Counter-Current Chromatography (HPCCC). Eight groups of Male Wistar rats (n = 64; 200-250 g) were used in the PILT model: Water control (C), P, 1/100 AICCL+P, 2/100 AICCL+P, 4/100 AICCL+P, Ethanol control (Et), Et+P, 1/1000 EICCW+P. Similar eight groups were used in the INIGU model (IN instead of P). Rats were orally pretreated with AICCL or EICCW (10 ml/kg) by intragastric gavage. Groups C and P/IN received distilled water. Groups Et and Et+P/IN received 20% Ethanol. The pretreatment in the PILT model lasted 7 days before a single intraperitoneal injection of P (1 g/kg) and two days afterwards. The duration of pretreatment in the INIGU model was 3 days, followed by a single intragastric treatment with IN (100 mg/kg). The effects were evaluated by biochemical, morphometrical and histopathological methods. The blood serum levels of aspartate aminotransferase were significantly lower in the group 1/100 AICCL+P, compared to group P. The hepatic parenchyma of group 1/100 AICCL+P was with preserved architectonics without necrosis. Morphometrical examinations of stomachs showed that the 2/100 AICCL significantly decrease the ulcer number and area. EICCW induced a reduction of the depth and severity of indomethacin-induced mucosal lesions. Our results demonstrated the hepatoprotective effect of 1/100 AICCL, and gastroprotective effect of 2/100 AICCL and Ð•ICCW in support of the scarce reports about internal usage of decoctions from C. coggygria. The most probable mechanism of these beneficial effects is the significant decrease of lipid peroxidation, due to the antioxidant properties of the plant investigated. Phytochemical analyses showed that the major components of the AICCL are gallotannins and gallic acid. Fustin and sulfuretin were the major bioflavonoid constituents of the EICCW.