N-Acetylcysteine and Milk Thistle for Treatment of Diabetic Nephropathy

Inclusion Criteria: * Males or females, age 18-70 years old. * Type 2 diabetes mellitus * Diabetic nephropathy, as defined by: * estimated GFR between 60 and 15 ml/min, * presence of proteinuria. * Current medical treatment with low dose aspirin * Treatment of hypertension with (but not limited to) one diuretic, one beta- blocker and one medication from the classes ARBs or ACE inhibitors. * Treatment of hyperglycemia with (but not limited to) glipizide and the medication class insulin. * Treatment of hypercholesterolemia with (but not limited to) one medication from the class statins. Exclusion Criteria: * Type 1 diabetes mellitus. * Glycosylated hemoglobin (HbA1C) \> 10% * \>20% variation in estimated GFR, during last 6 months * SBP \>170 mmHg or DBP \>100 mmHg on medications * Other secondary forms of hypertension (endocrine, renovascular) * History of intolerance to: * Both ACE-I and ARBs; * The investigational supplements; * Iodinated radiologic contrast material. * Known non diabetic renal disease, or history of solid organ transplantation. * Hepatitis virus or Human Immunodeficiency virus infections * Use of one of the following medications within 2 months prior to enrollment in the study: * Metformin. * Thiazolidinediones (pioglitazone or rosiglitazone); * Prescription-grade vitamin E, vitamin C, systemic steroids, and/or non-steroidal anti-inflammatory agents; * Over-the-counter vitamin E, vitamin C, and/or non-steroidal anti-inflammatory agents. * Over-the-counter antioxidants supplements including: Lipoic acid, Coenzyme Q10, N-acetyl-cysteine (NAC), Glutathione (GSH), Chromium, Fish-oil extracts (omega-3 fatty acids), Soy extracts (isoflavones), Milk thistle extract (silymarin), Green-tea preparations, Pomegranate extracts, Grape extracts, and Prickly pear extract. * Active coronary artery disease or cerebral vascular disease within 3 months prior to signing the informed consent. * Hepatic dysfunction as defined by abnormal total bilirubin or liver enzymes (ALT, AST) \>2 times upper limit of normal range. * Active malignancy. * History of drug or alcohol dependency. * Psychiatric or neurological condition, preventing aware consent to the study and/or adherence to the study protocol * Unwillingness to practice birth control throughout the study. * Participation to another clinical study within 1 month prior to signing the informed consent form. * Planned move to outside the study area, surgery or radiographic studies utilizing iodine-based contrast material within the next one year