Renoprotective effects of (+)-catechin in streptozotocin-induced diabetic rat model.
Diabetic nephropathy is a complication of diabetes mellitus leading to end-stage renal disease. Oxidative stress and inflammation play a major role in the pathogenesis of diabetic nephropathy. Green tea, known for its antioxidant and anti-inflammatory properties, has been shown to be renoprotective. We hypothesized that (+)-catechin (CTN), a component of green tea, is responsible for the renoprotection. Our investigation of the therapeutic potential of CTN in streptozotocin-induced diabetic rats demonstrated for the first time that the effects of CTN treatment were comparable with the effects of an angiotensin-converting enzyme inhibitor (ACEi) enalapril for the treatment of albumin excretion. After 12 weeks of CTN treatment with 35 mg/d in the drinking water, urinary albumin excretion and plasma creatinine concentrations in all the diabetic treatment groups were reduced, compared with the diabetic group with no treatment. Urine creatinine and creatinine clearance were higher in diabetic groups treated with CTN and ACEi compared with the diabetic group with no treatment. Endothelin 1, lipid peroxidation, concentration of alanine transferase enzyme, and expression of fibronectin were lower in all the treatment groups compared with the diabetic group with no treatment. Concentrations of free thiols were higher in the CTN-treated group compared with the diabetic rats with no treatment. Our findings suggest that CTN has renoprotective properties comparable with ACEi, and coadministration of CTN and enalapril might be useful in reducing albumin excretion as well as improving endothelial function. (+)-Catechin might be successfully used in the future for clinical situations where ACEi is poorly tolerated or contraindicated.
Department of Pediatrics, School of Medicine, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA.
Sudha P
SP
Chennasamudram
Shashi
S
Kudugunti
Purushotham Reddy
PR
Boreddy
Majid Y
MY
Moridani
Tetyana L
TL
Vasylyeva
D000410:Alanine Transaminase / Q000097:blood; D000419:Albuminuria / Q000188:drug therapy / Q000209:etiology; D000806:Angiotensin-Converting Enzyme Inhibitors; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology / Q000627:therapeutic use; D000975:Antioxidants / Q000494:pharmacology / Q000627:therapeutic use*; D028241:Camellia sinensis / Q000737:chemistry*; D002392:Catechin / Q000494:pharmacology / Q000627:therapeutic use*; D003404:Creatinine / Q000097:blood / Q000652:urine; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000150:complications / Q000188:drug therapy*; D003928:Diabetic Nephropathies / Q000097:blood / Q000517:prevention & control*; D004195:Disease Models, Animal; D004656:Enalapril / Q000494:pharmacology / Q000627:therapeutic use*; D019332:Endothelin-1 / Q000097:blood; D005353:Fibronectins / Q000097:blood; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D051381:Rats; D017207:Rats, Sprague-Dawley; D013438:Sulfhydryl Compounds / Q000097:blood
D000806:Angiotensin-Converting Enzyme Inhibitors; D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D019332:Endothelin-1; D005353:Fibronectins; D010936:Plant Extracts; D013438:Sulfhydryl Compounds; D004656:Enalapril; D002392:Catechin; D003404:Creatinine; D000410:Alanine Transaminase