Effects of Hypericum perforatum (St. John's wort) extract on renal function after unilateral ureteral obstruction in rat

Abstract

Obstructive nephropathy induced by urine reflux due to uroliths, prostatic hypertrophy and other disorders will result in renal interstitial fibrosis and inflammation. Because of Hypericum perforatums (HP) anti-oxidant and anti-inflammatory properties, the clinical usage of this drug in renal function has been studied. We divided 30 Sprague-Dawley rats randomly into 5 groups: sham group (Sham), untreated unilateral ureteral obstruction (UUO) group, vitamin E treated (50 IU/kg) UUO group, HP 30 and 60 treated (30 and 60 mg/kg) UUO groups. All of the chemicals were administrated 7 days before and after operation. At 7 days after UUO, blood samples were collected and left kidney were dissected and Haematoxylin and Eosin (HE) and Masson staining were used to study the dynamic histological changes. Low dose of HP similar to vitamin E alleviated the renal interstitial fibrosis, tubular cell degeneration, inflammatory cell infiltration and glomerular damage (p<0.01) but high dose of HP increased injuries (p<0.05). We provide for the first time evidence that HP extract in obstructed kidney has different effects, such that in low dose it can be affected as a renoprotective agent, but in high dose, it can be affected as an inflammation triggering substance. The demonstration of exact mechanism (s) of opposite effect of HP extracts needs more cellular and molecular investigations.