Min Ho Cho, Dol Mi Kim, Chul Sik Kim, Joug Suk Park, Joo Young Nam, Jin Hyuck Chang, Jina Park, Chul Woo Ahn, Bong Soo Cha, Sung Kil Lim, Kyung Rae Kim, Hyun Chul Lee
Korean Diabetes J. 2004;28(6):554-557. Published online December 1, 2004
The relationship between angiotensin converting enzyme inhibition and hypoglycemia remains controversial. An 82-year-old, nondiabetic woman who had taken ramipril 5 mg with amiloride 5 mg for two months was admitted to the hospital because of her altered mentality. Her plasma glucose was 1.5 mmol/L and she regained her consciousness after normalization of the plasma glucose. The recurrent attacks of hypoglycemia ended when she stopped taking ramipril. Her hypoglycemia was thought to result from the combined deficiency of catecholamines and cortisol that was induced by a deficiency of angiotensin II. The glucagoninsensitivity was thought to result from a chronic elevation of bradykinin due to the ACE inhibitor, and the relative hyperinsulinemia was though to be cased by the amiloride.
Hye Jung Lee, Hyuk Sang Kwon, Jin Hee Lee, Sung Koo Kang, Yoon Hee Choi, Sung Ha Hwang, Seung Hyun Ko, Jung Min Lee, Kun Ho Yoon, Bong Yun Cha, Won Chul Lee, Kwang Woo Lee, Ho Young Son
Korean Diabetes J. 2004;28(5):416-424. Published online October 1, 2004
BACKGROUND Angiotensin converting enzyme (ACE) inhibitors are becoming increasingly popular as the first-choice antihypertensive agents for diabetic patients. This could be partly related to their suggested beneficial effects on insulin sensitivity. This study was designed to compare the effect of captopril with that of control (nitrendipine) on insulin sensitivity for subjects with insulin resistance. METHODS: 24 subjects, aged less than 60 years, with their insulin resistance being defined as the area under the curve (AUCi) of insulin that was 2 standard deviations (SD) more than that of the control subjects during oral glucose tolerance test were recruited. A randomized, double-blind, crossover trial was conducted for an 8 weeks treatment period with captopril and the control (nitrendipine) that was given after an initial 6 weeks run-in period. Anthropometric measurement including weight, height, waist and hip circumference, blood pressure (systolic & diastolic), lipid profile blood chemistry, electrolytes levels & renal function testing, and frequently sampled intravenous glucose tolerance tests (FSIGT) for the insulin sensitivity index (SI) & acute insulin response to glucose (AIRg) were also done before and after treatment, respectively. RESULTS: 18 subjects (6 males, 12 females) completed the study. The mean age of the study subjects was 47.9+/-2.9 years (mean+/-SEM), and their BMI was 28.0+/-0.7 kg/m2 (mean+/-SEM).There was a significant decrease in weight (baseline; 71.5+/-9.2 kg vs. captopril; 70.7+/-9.0 kg and nitrendipine; 709+/-9.2 kg, p<0.05, respectively) and BMI (baseline; 28.0+/-3.0 kg/m2 vs. captopril; 27.7+/-2.8 kg/m2 and nitrendipine; 27.8+/-2.9 kg/m2, p<0.05, respectively) for both groups compared with the baseline, but there are no significant differences between the two groups. Triglyceride was significantly decreased after treatment with captopril compared to the baseline and nitrendipine (187.0+/-99.5 mg/dL vs. 224.5+/-134.2 mg/dL, respectively, p<0.05). The SI was significantly increased after captopril treatment compared with the baseline (1.4+/-1.0 vs. 2.5+/-0.8 min-1 per mU/ml, respectively, p<0.05), and the captopril group was significantly higher than that of nitrendipine (1.5+/-1.0 min-1 per mU/ml, p <0.05). Acute insulin response to glucose in both groups was also increased after treatment, but there was no statistically significance. CONCLUSION: Captopril therapy improved insulin sensitivity, and it decreased the concentration of fasting insulin in subjects with insulin resistance.
Seung Hyun Ko, Kun Ho Yoon, Myung Mi Kim, Yu Bae Ahn, Ki Ho Song, Soon Jib Yoo, Hyun Shik Son, Bong Yun Cha, Kwang Woo Lee, Ho Young Son, Sung Koo Kang
Korean Diabetes J. 2001;25(6):469-482. Published online December 1, 2001
BACKGROUND In a Heart Outcomes Prevention Evaluation HOPE study, ramipril, a long- acting angiotensin-converting enzyme (ACE) inhibitor, significantly reduced the death rates the number of myocardial infarctions, strokes, heart failure as well as the risk of complications related to diabetes and of diabetes itself. However, it is known that ACE inhibitors improve glucose tolerance or insulin sensitivity or reduce the incidence of diabetes. METHODS: 24 week-old OLETF (Otsuka Long Evans Tokushima Fatty) rats weighing 400~450 g were used in this study. 4 groups of rats were examined in parallel for 40 weeks. The OLETF rats were randomized for treatment with an aqueous solution of ramipril ( 5mg/Kg) daily [OL (RMP), n=10)] and with saline [OL(CON), n=10)]. The LETO rats were also randomized in the same was as the OLETF rats (LT (RMP), n=10, LT (CON), n=10). The blood glucose level, body weight, systolic and diastolic blood pressure was assessed every month. At 3 and 6 months, the 24hrs urinary protein concentration was measured, and as insulin tolerance test and oral glucose tolerance test were conducted in all experimental groups. After 6 months, the body weight was matched for 2 months in each corresponding group. Subsequently, a 15% sucrose loading was done for 2 months. After the glucose tolerance test, the pancreas was excised and immunohistochemical staining was conducted for insulin to quantify the beta cell mass by a point-counting method. In addition, the islet morphology was evaluated in the pancreas. RESULTS: Ramipril treatment for a period of 6 months improved the 2hr blood glucose level, the area under the glucose curve in the oral glucose tolerance test, insulin sensitivity in addition to lowering significantly systolic and diastolic blood pressure and 24hrs urinary protein level significantly in OLETF rats. Of note, a lower weight gain was observed in both the ramipril-treated animals at 6 months. After weight matching, the AUCg and 2hr blood glucose level values were similar between the corresponding groups, but a 15% sucrose loading worsened the AUCg value. Histologically, the islets were less disorganized and the extent of fibrosis was lower in the ramipril- treated OLETF rats in the trichrome stain. CONCLUSION: Long-term treatment of ramipril, a long acting angiotensin-converting enzyme inhibitor may be useful for suppressing weight gain and proteinuria in addition to having aprotective effect on the islet to harmful stimuli such as hyperglycemia.