Coleus amboinicus extract increases transforming growth factor-1β expression in Wistar rats with cisplatin-induced nephropathy.

Coleus amboinicus (CA) plants are known to exert antibacterial and anti-inflammatory effects and demonstrate antiproliferative effects against cancer cells. This study aimed to investigate the activity of CA extract on the expression of transforming growth factor-1β (TGF-1β) in cisplatin-induced nephropathy in Wistar rats (Rattus norvegicus).

CA was obtained from fresh leaves of CA and was extracted using 96% ethanol maceration. This blinded, controlled, randomized post-test study assigned 24 Wistar rats to three groups (n=8). Negative controls received normal saline (P0), nephropathy was induced in rats by cisplatin (5 mg/kg, IP) (P1), and treated with ethanolic coleus extract (500 mg/kg, PO) (P2), respectively, for 7 days. Nephropathy was induced on the 4^th day. All rats were sacrificed on the 8^th day for blood and kidney sample collection. Concentrations of blood urea nitrogen (BUN), creatinine, and alkaline phosphatase were analyzed using colorimetric analysis. A semi-quantitative analysis was performed on sectioned kidneys to determine the numbers of positive cells for TGF-1β expression and to evaluate structural and functional alterations in the kidneys using histopathological and immunohistochemical staining.

The concentrations of BUN, creatinine, and alkaline phosphatase from blood samples in the treatment group were significantly lower than those of the control group (p<0.05). Morphological evaluation of the tubular interstitium and glomeruli revealed that necrotic, degenerating, and infiltration of cells significantly decreased in the treatment group compared to the control group (p<0.05). The mean immunostaining scores indicating the presence of TGF-1β were 7.8 in the ethanolic coleus extract group, 3 in the induction group, and 2.3 in the control group. The expression scores for TGF-β1 were significantly different between the ethanolic coleus extract treatment and control group (p<0.05).Our results suggest that in Wistar rats with cisplatin-induced nephropathy, CA extract inhibits pathological lesions by regulating the renal expression of TGF-1β in areas containing the renal tubules and glomeruli.