Ruellia tuberosa L. Extract Improves Histopathology and Lowers Malondialdehyde Levels and TNF Alpha Expression in the Kidney of Streptozotocin-Induced Diabetic Rats

Abstract

Ruellia tuberosa L. is a therapeutic plant that is generally consumed in Indonesian traditional medicine to prevent or cure various illnesses, i.e., diabetes. The current study was conducted to investigate the effects of hydroethanolic root extracts of Ruellia tuberosa L. on the kidney of streptozotocin-induced diabetic Wistar rats. In this study, male Wistar rats were divided into 5 groups: healthy rats (group 1), diabetic rats (group 2), and treated rats which received extract at dosages of 250 (group 3), 375 (group 4), and 500 (group 5) mg/kg body weight for 21 days. Diabetes mellitus was experimentally induced by the administration of five doses of streptozotocin 20 mg/kg body weight within five consecutive days. Significant increases in the value of TNF alpha expression and malondialdehyde (MDA) levels were observed in streptozotocin-induced diabetes rats. Furthermore, severe histological alterations of kidney tissues occurred in the diabetic rats group. After treatment was applied, the value of TNF alpha expression and MDA levels on the kidney decreased considerably (p < 0.05) in groups 3, 4, and 5. The optimum dosage was obtained at a dose of 250 mg/kg body weight (group 3), which had 42.24% and 52.70% decrease in TNF alpha expression and MDA levels, respectively. The histopathological profiles of the kidney also showed significant improvements in treated groups. The most prominent recoveries were also shown in group 3. The treatments induced repairment in the glomerular and renal tubular damages in the kidney tissues. To conclude, these results emphasize potentially health valuable properties of hydroethanolic root extracts of R. tuberosa L. in rats with streptozotocin-induced diabetes.

Figure 1

TNF alpha expression in the kidney of (a) healthy rats (group 1), (b) diabetic rats (group 2), (c) diabetic rats that treated with 250 mg/kg body weight extracts per day (group 3), (d) diabetic rats that treated with 375 mg/kg body weight extracts per day (group 4), and (e) diabetic rats that treated with 500 mg/kg body weight extracts per day (group 5). The red arrows show renal tubules with TNF alpha expression.

Figure 2

Histopathological profiles of the kidney of (a) healthy rats (group 1), (b) diabetic rats (group 2), (c) diabetic rats that treated with 250 mg/kg body weight extracts per day (group 3), (d) diabetic rats that treated with 375 mg/kg body weight extracts per day (group 4), and (e) diabetic rats that treated with 500 mg/kg body weight extracts per day (group 5). Number 1 shows overview of the kidney with 10× magnification, number 2 shows glomerulus area with 40× magnification, and number 3 shows tubules with 40× magnification. Black arrows show glomerulus, yellow arrows show proximal tubules, and blue arrows show Bowman's space.