curcumin and Glycosuria

We investigated the effects of prolonged treatment of diabetic rats with curcumin-supplemented yoghurt on the physiological and biochemical changes associated with diabetes mellitus. An established metabolic cage model was used to assess these changes in three groups of streptozotocin-diabetic rats which had been administered, by gavage, curcumin blended into yoghurt in the doses of 30, 60 and 90 mg/kg body weight (BW) per d (groups DC30, DC60, DC90) for 31 d. One group of non-diabetic rats was also treated with 90 mg/kg BW per d curcumin (NDC90). Three control groups of diabetic animals received water (DW), yoghurt (DY) and insulin at 27·78 μmol/d by subcutaneous injection (DI). Also, two groups of non-diabetic animals received water (NDW) and yoghurt (NDY). Groups DI and DC90 exhibited significant falls, relative to DW and DY, in food and water intake, urine volume, glycaemia, urinary urea and glucose, proteinuria, serum TAG and activities of aspartate and alanine aminotransferases, and higher hepatic glycogen and BW. These improvements were greater in DI than in DC90. No difference was observed in the serum levels of total cholesterol or HDL-cholesterol, or in the masses of adipose and muscular tissues, between DC90 and DW or DY. Moreover, the improvements in curcumin-treated rats, relative to DW and DY, were significant and dose-dependent. The NDC90 group also showed no difference from the NDW or NDY groups, in any of the markers for diabetes. In conclusion, curcumin mixed into yoghurt at the highest dose tested exhibited anti-diabetic activity, improving significantly most of the markers assessed in this study.

Topics: Animals; Biomarkers; Blood Glucose; Cholesterol; Curcumin; Diabetes Mellitus, Experimental; Dietary Supplements; Dose-Response Relationship, Drug; Drinking; Eating; Glycosuria; Male; Rats; Rats, Wistar; Urea; Yogurt

Curcumin is a potent inhibitor of the transcription factor activator protein-1 which plays an essential role in osteoclastogenesis. However, the effects of curcumin on bone metabolism have not been clarified in vivo. We reported herein the inhibitory effects of curcumin on the stimulated osteoclastic activity in insulin-dependent diabetes mellitus using rats with streptozotocin-induced diabetes. A dietary supplement of curcumin reversed the increase in levels of activity and mRNA of tartrate-resistant acid phosphatase (TRAP) and cathepsin K to control values. A histochemical analysis showed that the increase in TRAP-positive cells in the distal femur of the diabetic rats was reduced to the control level by the supplement. These results suggested that curcumin reduced diabetes-stimulated bone resorptive activity and the number of osteoclasts. When bone marrow cells were cultured with macrophage colony stimulating factor and receptor activator NF-kappaB ligand (RANKL), the increased activity to form TRAP-positive multinucleated cells and the increased levels of mRNA and protein of c-fos and c-jun in the cultured cells from diabetic rats decreased to control levels in the curcumin-supplemented rats. Similarly, the increased expression of c-fos and c-jun in the distal femur of the diabetic rats was significantly reduced by the supplement. These results suggested that curcumin suppressed the increased bone resorptive activity through the prevention of osteoclastogenesis associated with inhibition of the expression of c-fos and c-jun in the diabetic rats.

Topics: Acid Phosphatase; Amino Acids; Animals; Blood Glucose; Body Weight; Bone Marrow Cells; Bone Resorption; Calcium; Cathepsin K; Cell Differentiation; Curcumin; Diabetes Mellitus, Experimental; Dietary Supplements; Eating; Female; Femur; Glycosuria; Hydroxyproline; Isoenzymes; Osteocalcin; Osteoclasts; Rats; RNA, Messenger; Staining and Labeling; Stem Cells; Streptozocin; Tartrate-Resistant Acid Phosphatase