Abstract

Background:
Hyperuricemia is a key risk factor for gout and other metabolic disorders. Conventional xanthine oxidase (XO) inhibitors like allopurinol, can cause adverse effects, prompting the search for natural alternatives. Tribulus terrestris (T. terrestris) is a traditional medicinal plant with diuretic and anti-inflammatory properties.

Aim:
This study aimed to evaluate the in-vitro antioxidant and anti-inflammatory activities, and the in-vivo hypouricemic and xanthine oxidase inhibitory effects of a methanolic extract of T. terrestris fruit (TTFME) in a hyperuricemic rat model.

Methods:
Hyperuricemia was induced in Wistar rats by using yeast extract and potassium oxonate. The rats were treated with TTFME (200 and 400 mg/kg) and allopurinol (5 mg/kg) for 40 days. In-vitro assays assessed 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and inhibition of albumin denaturation. Serum uric acid levels, XO activity, liver and kidney function markers, and globulin levels were measured in-vivo.

Results:
TTFME showed weak in-vitro antioxidant activity (16.7% DPPH scavenging), but potent, dose-dependent anti-inflammatory activity (84.4% inhibition at 300 µg/ml). In hyperuricemic rats, both doses of TTFME significantly reduced serum uric acid levels to normal levels, comparable to those of allopurinol. Notably, 200 mg/kg TTFME exhibited superior XO inhibition (77.5%) compared to allopurinol (72.2%). The extract also significantly lowered elevated serum globulin and creatinine levels, indicating its anti-inflammatory and nephroprotective effects.

Conclusion:
Tribulus terrestris fruit extract has potent hypouricemic, xanthine oxidase inhibitory, and anti-inflammatory properties, supporting its potential as a natural therapeutic or adjunctive agent for managing hyperuricemia and gout.

Key words: Anti-inflammatory; Antioxidant; Hyperuricemia; Tribulus terrestris; Xanthine Oxidase.