Silymarin and milk thistle extract may prevent the progression of diabetic nephropathy in streptozotocin-induced diabetic rats.
OBJECTIVE
To investigate the effect of silymarin and milk thistle extract on the progression of diabetic nephropathy (DN) in rats.


METHODS
Diabetes was induced with a single intraperitoneal (IP) injection of streptozotocin (STZ) (60 mg/kg). Silymarin (100 mg/kg/d) or the extract (1.2 g/kg/d) was gavaged for 4 weeks. Blood glucose (BS), serum urea (S(u)), serum creatinine (S(cr)), and 24-h urine protein (Up) were measured and glomerular filtration rate (GFR) was calculated. Concentration of thiobarbituric acid reactive species (TBARS) and activities of glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) were evaluated in the renal tissue.


RESULTS
Data were expressed as mean +/- SEM. Silymarin or the extract had no significant effect on BS, S(cr), and GFR. Both milk thistle extract and silymarin, respectively, decreased S(u) (mg/dL) (87.1 +/- 7.78, p < 0.001; 84.5 +/- 7.15, p < 0.001), Up (mg) (5.22 +/- 1.56, p = 0.014; 5.67 +/- 0.86, p = 0.034), and tissue TBARS (nmol/mg protein) (0.67 +/- 0.04, p < 0.001; 0.63 +/- 0.07, p < 0.001) in diabetic rats, compared to diabetic control (DC) (S(u): 131.0 +/- 4.55, Up: 8.3 +/- 0.84, TBARS: 0.94 +/- 0.06). Both the extract and silymarin could increase the activity of CAT (IU/mg protein) (25.5 +/- 4.0, p = 0.005; 20 +/- 1.8, p = 0.16) and GPx (IU/mg protein) (0.86 +/- 0.05, p = 0.005; 0.74 +/- 0.04, p = 0.10), respectively, in diabetic rats compared to DC (CAT = 14.4 +/- 2.0, GPx = 0.57 +/- 0.02).


CONCLUSIONS
Milk thistle extract, to a lesser extent silymarin, can attenuate DN in rats possibly by increasing kidney CAT and GPx activity and decreasing lipid peroxidation in renal tissue.
Vessal
Ghazal
G
Department of Clinical Pharmacy, Shiraz Pharmaceutical Research Center, Faculty of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Islamic Republic of Iran. gvessal@yahoo.com
Akmali
Masoumeh
M
Najafi
Parisa
P
Moein
Mahmood Reza
MR
Sagheb
Mohammad Mahdi
MM
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced; D003928:Diabetic Nephropathies / Q000517:prevention & control*; D018450:Disease Progression; D008297:Male; D020944:Silybum marianum; D008517:Phytotherapy; D010936:Plant Extracts / Q000627:therapeutic use*; D020011:Protective Agents / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012838:Silymarin / Q000627:therapeutic use*; D013311:Streptozocin
D010936:Plant Extracts; D020011:Protective Agents; D012838:Silymarin; D013311:Streptozocin