N-Acetylcysteine and Milk Thistle for Treatment of Diabetic Nephropathy

Inclusion Criteria: * Males or females age 18-76 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 Angiotensin Receptor Blockers (ARBs) or Angiotensin Converting Enzyme inhibitors (ACE-I) * 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 * Systolic Blood Pressure \>170 mmHg or Diastolic Blood Pressure \>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) * Phenytoin * Warfarin * 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 * 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