Protective Effect of a Bioflavonoid Proanthocyanidin-BP1 in Glycerol-Induced Acute Renal Failure in the Rat: Renal Stereological Study

Abstract

Renal ischemia as well as oxygen metabolites play an important role in renal injury during myoglobinuric acute renal failure (ARF). On the other hand, flavonoids, a diverse group of constituents naturally occurring in plants, have a strong antioxidative activity, and have been implicated in vascular relaxation. In this study the protective effect of a new bioflavonoid proanthocyanidin-BP1 (BP1), extracted from seeds of grapes, was evaluated in glycerol-induced ARF in rats. Stereological methods were used to quantify changes in renal morphology associated with ARF. Volume density of tubular lumen and intratubular cast formations, nuclear parameters (area, diameter, volume) of epithelial cells in the cortical proximal tubules, and glomerular parameters (surface area, diameter, volume, perimeter) were estimated on kidney sections of rats treated either with 50% glycerol (8 mL/kg i.m.) alone. BP1 (20 mg/kg i.p.) in addition to glycerol, or BP1 alone. It was noted that the volume density of tubular lumen and cast formations were significantly lower (p < 0.001) in kidneys of the rats treated with BP1 in addition to glycerol, compared with those treated with glycerol alone. There were no significant differences in glomerular and nuclear parameters between glycerol treated, and BP1 in addition to glycerol treated rats. Renal function was significantly improved in rats treated with BP1 in addition to glycerol. The results suggest that BP1 is a protective agent in glycerol model of ARF. This effect is probably due to the antioxidative activity of BP1 and reduced toxicity of myoglobin in renal tissue. Moreover, it is possible that the ability of BP1 to protect the kidney is dependent upon renal vascular relaxation. The potential beneficial effects of bioflavonoid-BP1 demonstrated in experimental ARF could be considered in therapy of myoglobinuric ARF.

Amelioration of myoglobinuric renal damage in rats by chronic exposure to flavonol-rich red wine

“…Also, a renoprotective effect by the wine bioflavonoid proanthocyanidin-BP1 was reported in a study examining the same glycerol-induced rhabdomyolysis animal model used in the present experiments [20]. It is unlikely that extrarenal effects of the treatments and of rhabdomyolysis contributed to the observed renal protection since systemic parameters other than FRAP, such as haemodynamics and uricaemia, were not different between the groups at basal conditions or after glycerol injection.…”

Does silybin protect against toxicity induced by polymyxin E in rat kidney?

“…Several mechanisms have been proposed for the protective effect of silybin. For instance, as an antioxidant, it may scavenge ROS via chelating ferric ions . As an antiinflammatory, it may decrease cyclooxygenase‐2 expression by interfering with nuclear factor κ‐ß or degrade tumor necrosis factor‐α by increasing expression of dipeptidylpeptidase IV in renal tubular cells .…”

Protective effect of polyphenol-containing azuki bean (Vigna angularis) seed coats on the renal cortex in streptozotocin-induced diabetic rats

“…Azuki beans are known to contain polyphenols such as proanthocyanidins with remarkable radical scavenging activities in vitro [1,2]. Proanthocyanidins have some preventive effects against oxidative damage associated with a variety of diseases, including inflammation, cardiovascular diseases, atherosclerosis and diabetes [4][5][6]. However, little is known about whether a diet of seed coats of the azuki bean has beneficial effects on diabetic nephropathy.…”

“…Generally, proanthocyanidins are known to be natural antioxidants that possess protective properties against oxidative stress. For example, grape seed proanthocyanidins extract has been reported to have beneficial effects on inflammation [4][5][6], cancer [7,8] and diabetes [9,10]. Recently, we demonstrated that polyphenol-containing azuki bean seed coats attenuated the increase of infiltrating macrophages and tubulointerstitial fibrosis in kidneys of rats induced by cisplatin, which has been used as a chemotherapeutic agent against malignant carcinoma [11].…”