- Protective Effects of Lithospermate B on Diabetic Nephropathy in OLETF Rat.
-
Hyun Joo Lee, Geun Taek Lee, Eun Seok Kang, Kyu Yeon Hur, Zheng Shan Zhao, Chul Woo Ahn, Hun Joo Ha, Man Kil Jung, Bong Soo Cha, Hyun Chul Lee
-
Korean Diabetes J. 2005;29(4):322-332. Published online July 1, 2005
-
-
-
Abstract
PDF
- BACKGROUND
Magnesium lithospermate B(LAB), an active component isolated from Salvia milltiorrhizae, has been reported to have renoprotective effects in type 1 diabetic animal model. The purpose of this study was to examine the effects of LAB on the prevention of diabetic nephropathy in Otsuka Long-Evans Tokushima Fatty(OLETF) rat which is regarded as an animal model of type 2 diabetes. METHODS: Ten microgram of LAB/kg or Vehicle(PBS) was given orally once daily to 10-week-old male OLETF rats and LETO rats for 40 weeks. Intra-peritoneal glucose tolerance test was performed at 50 weeks. 24 hr urinary protein excretion amounts were measured. Lipid peroxidation, TGF-beta1 and ED-1 of renal cortex were measured. RESULTS: The mean body weight of LAB+OLETF was not significantly different from that of OLETF rats. LAB treatment decreased proteinuria, lipid peroxidation, and free fatty acid in OLETF rats without decrease in the plasma glucose concentration. Also, LAB inhibited the progression of glomerular hypertrophy and mesangial expansion. LAB effectively decreased ED-1 positive cells, ECM expansion, and TGF-beta1 level in the renal cortex of OLETF rats. CONCLUSIONS: These results suggest that the beneficial effects of LAB on the diabetic renal damage in the OLETF rats may depend on a mechanism of decreasing oxidative stress. LAB might be a new therapeutic agent for the prevention of nephropathy in type 2 diabetes as well as type 1 diabetes.
- Efficacy of Serum Leptin Level as an Indicator to Predict the Clinical Response of Rosiglitazone in Patients with Type 2 Diabetes Mellitus.
-
Jae Hyuk Lee, Soo Kyung Kim, Kyu Yeon Hur, Han Seok Choi, Ji Young Jung, Wan Sub Shim, Hyun Joo Lee, Chul Woo Ahn, Sung Kil Lim, Kyung Rae Kim, Hyun Chul Lee, Bong Soo Cha
-
Korean Diabetes J. 2003;27(5):420-432. Published online October 1, 2003
-
-
-
Abstract
PDF
- BACKGROUND
Leptin is a protein secreted by adipocytes that regulates food intake by acting on the hypothalamus and is correlated with body fat mass. Insulin resistance is also correlated with body fat mass and obesity. Rosiglitazone (RSG) is known as a highly selective and potent agonist for the peroxisome proliferator-activated receptor-gamma (PPARgamma). It improves glycemic control by improving insulin sensitivity in peripheral tissue. This study was performed to evaluate the antidiabetic and insulin sensitizing effects of RSG combination therapy and the efficacy of serum leptin level as an indicator to predict the clinical response of RSG in type 2 diabetic patients with oral agents such as metformin and/or sulfonylurea. METHODS: The study subjects were 140 type 2 diabetic patients (90 male, 50 female) who received a 12-week course of daily 4 mg RSG, in addition to the previous medications. The glucose level, indices of insulin resistance and metabolic parameters were measured. Serum leptin level was measured by radioimmunoassay before and after RSG treatment. Visceral fat and subcutaneous fat were measured by sonography. RESULTS: After 12 weeks of RSG treatment, FPG (12.6+/-28.1 mg/dL), HOMAIR (0.3+/-0.9), serum fasting insulin (1.9+/-4.7 microU/mL), SBP and DBP had all decreased significantly, whereas body weight, BMI, waist circumference, WHR, body fat mass, and subcutaneous fat had all increased. Serum leptin level also tended to increase after RSG treatment, but without significance. deltaFPG (delta=value after treatment- value before treatent) was inversely correlated with basal serum leptin level (r=-0.202), basal HOMAIR (r=-0.226) and basal FPG (r=-0.565). There was no correlation between deltaFPG and basal BMI or serum insulin level. RSG treatment showed significant inverse correlation between serum leptin level and deltaHOMAIR (r=-0.416), delta insulin (r=-0.365) and deltaHbA1c (r=-0.189). Serum leptin level was positively correlated with the subcutaneous fat amount (r=0.548), basal BMI (r=0.521), and basal HOMAIR (r=0.343). CONCLUSION: These results showed that RSG treatment can improve not only hyperglycemia but also insulin resistance in type 2 diabetic patients. The serum leptin level at baseline can be used as an indicator to predict the clinical response of RSG treatment in type 2 diabetes patients.
|