Ziziphus abyssinica hydro-ethanolic root bark extract attenuates acute inflammation possibly through membrane stabilization and inhibition of protein denaturation and neutrophil degranulation

Abstract

Background: Despite the widespread use of Ziziphus abyssinica (ZAE) roots and claims of its efficacy against diverse inflammatory conditions in traditional medicine, there is paucity of information on the scientific basis for its folkloric use. Objectives: The current study evaluated the anti-inflammatory property of the root bark extract of ZAE and its possible mechanism(s) of action in in vivo and in vitro experimental models. Methods: Anti-inflammatory activity of ZAE was assessed in vitro using heat and hypotonic solution – induced haemolysis as well as egg albumin (EA) and bovine serum albumin (BSA) denaturation assays. Carrageenan and formalin-induced paw oedema and carrageenan-induced peritonitis in rats were used to evaluate the anti-inflammatory property of the extract in vivo. Results: ZAE (100, 300 and 1000 µg/mL) significantly inhibited heat and hypotonic solution-induced haemolysis as well as EA and BSA-induced denaturation. ZAE (300 mg/kg, p.o.) similar to diclofenac (10 mg/kg, p.o.), significantly (P<0.05) reduced paw oedema by 40.77±6.82 and 54.81 ± 3.74% respectively in carrageenan-induced paw oedema test. The percentage inhibitions produced by ZAE (30, 100 and 300 mg/kg, p.o.) were 3.31±22.12, 49.89±2.98 and 76.98±0.50 % respectively compared to 80.51±0.53 % produced by diclofenac (10 mg/kg, p.o.) in the formalin-induced paw oedema test. Massive recruitment of leukocytes (mainly neutrophils) into the peritoneal cavity of the rats by carrageenan was significantly (P<0.01) reduced by ZAE (30, 100 and 300 mg/kg p.o.) and dexamethasone (5 mg/kg, p.o.). Conclusions: The inhibitory effect of ZAE against acute inflammation in this study provides scientific basis for its use in folk medicine and reveals its potential as a source of novel anti-inflammatory agent.