Effect of Soursop (Annona muricata) Leaf Extract on the Kidney Histology of Adult Albino Rats Induced with Cadmium

Abstract

Cadmium is a pervasive environmental toxicant with a long biological half-life, and the kidney, owing to its high blood flow and filtration role, is particularly vulnerable to cadmium-induced injury characterised by oxidative stress, tubular necrosis, and fibrosis. Annona muricata (soursop) leaf extract, rich in flavonoids, alkaloids, and acetogenins, has shown antioxidant and organ-protective properties in prior studies, but direct evidence of its effect on cadmium-induced kidney histology remains limited. This study investigated the effect of graded doses of Annona muricata leaf extract on body weight and kidney histology in cadmium-induced adult albino rats. Fifty rats were divided into five groups of ten: Group A (control), Group B (cadmium plus low-dose extract, 200 mg/kg), Group C (cadmium plus medium-dose extract, 400 mg/kg), Group D (cadmium plus high-dose extract, 800 mg/kg), and Group E (cadmium only). Cadmium chloride (0.5 mg/kg) and the extract were administered orally for two weeks, after which kidney tissue was processed and stained with haematoxylin and eosin for histological examination and additionally graded by two blinded observers using a semi-quantitative severity scale (0 = normal to 3 = severe). All groups showed significant within-group weight gain from baseline to endpoint (p < 0.001), with the cadmium-only group showing the least gain and greatest variability (p = 0.004). Histologically, the control (score 0) and high-dose (score 0) groups showed normal kidney architecture, while the cadmium-only group showed severe haemorrhage and fibrosis (score 3). Low-dose (score 2) and medium-dose (score 1) groups showed intermediate changes, mild haemorrhage and fibrosis, and mild inflammatory infiltration, respectively, consistent with an apparent dose-related pattern of histological change. These findings suggest that Annona muricata leaf extract, particularly at higher doses, may reverse cadmium-induced renal toxicity and growth suppression in rats, although this pattern is based on semi-quantitative histological grading rather than formal statistical comparison between groups, and should be confirmed by future studies incorporating quantitative morphometry and biochemical renal-function markers.