scholarly journals Selective β-Cell Loss and α-Cell Expansion in Patients with Type 2 Diabetes Mellitus in Korea

2003 ◽  
Vol 88 (5) ◽  
pp. 2300-2308 ◽  
Author(s):  
Kun Ho Yoon ◽  
Seung Hyun Ko ◽  
Jae Hyoung Cho ◽  
Jung Min Lee ◽  
Yu Bae Ahn ◽  
...  
Keyword(s):  
Cell Mass ◽  
Cell Loss ◽  
Relative Volume ◽  
Diabetic Patients ◽  
Organ Donors ◽  
Β Cells ◽  
Β Cell ◽  
Type 2 Diabetic Patients ◽  
Type 2 Diabetic

In the presence of obesity, β-cell mass needs to be increased to compensate for the accompanying demands and maintain euglycemia. However, in Korea, the majority of type 2 diabetic patients are nonobese. We determined the absolute masses, relative volumes, and ratio of α- and β-cell in the pancreas and islets in normal and diabetic Korean subjects to correlate these findings with the clinical characteristics. Whole pancreases procured from organ donors were divided into 24 parts (control 1, n = 9). Tissue was also obtained by surgical resection after 35 partial pancreatectomies: in 25 diabetic patients, 10 age- and body mass index (BMI)-matched patients of benign or malignant pancreatic tumor without diabetes mellitus (DM) (control 2). Morphometric quantifications were performed. In control 1, the relative volume of β-cells was 2.1 ± 0.9%, and the total β-cell mass was 1.3 ± 0.3 g. The relative volume of β-cells was found to be variable (control 1, 2.1 ± 0.9%; control 2, 1.9 ± 0.7%; DM, 1.4 ± 1.0%; P < 0.05 DM vs. control 1 and 2) and showed good correlation with BMI (control 1, r2 = 0.64; DM, r2 = 0.55; all subjects, r2 = 0.38; P < 0.05). Notably, in type 2 diabetic patients, the ratio of α-cell area to β-cell area in the islet was higher than in control 1 and 2 (0.81 ± 0.4 vs. 0.29 ± 0.2, 0.20 ± 0.1, P < 0.05). Additionally, significant α-cell expansion and a decreased β-cell fraction were predominantly observed in larger islets (islet area, >6415 μm2; P < 0.05) in control 1 and diabetic patients. The relative volume of β-cell was found to be correlated with BMI in diabetic patients and normal organ donors. Moreover, decreased β-cell but increased α-cell proportion in the islets suggests for a selective β-cell loss in the pathogenesis of Korean type 2 diabetes.

scholarly journals Resveratrol improves insulin sensitivity, reduces oxidative stress and activates the Akt pathway in type 2 diabetic patients

2011 ◽  
Vol 106 (3) ◽  
pp. 383-389 ◽  
Author(s):  
Pál Brasnyó ◽  
Gergő A. Molnár ◽  
Márton Mohás ◽  
Lajos Markó ◽  
Boglárka Laczy ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Insulin Resistance ◽  
Insulin Sensitivity ◽  
Cell Function ◽  
Diabetic Patients ◽  
Β Cell ◽  
Type 2 Diabetic Patients ◽  
Β Cell Function ◽  
Type 2 Diabetic

Although resveratrol has widely been studied for its potential health benefits, little is known about its metabolic effects in humans. Our aims were to determine whether the polyphenol resveratrol improves insulin sensitivity in type 2 diabetic patients and to gain some insight into the mechanism of its action. After an initial general examination (including blood chemistry), nineteen patients enrolled in the 4-week-long double-blind study were randomly assigned into two groups: a resveratrol group receiving oral 2 × 5 mg resveratrol and a control group receiving placebo. Before and after the second and fourth weeks of the trial, insulin resistance/sensitivity, creatinine-normalised ortho-tyrosine level in urine samples (as a measure of oxidative stress), incretin levels and phosphorylated protein kinase B (pAkt):protein kinase B (Akt) ratio in platelets were assessed and statistically analysed. After the fourth week, resveratrol significantly decreased insulin resistance (homeostasis model of assessment for insulin resistance) and urinary ortho-tyrosine excretion, while it increased the pAkt:Akt ratio in platelets. On the other hand, it had no effect on parameters that relate to β-cell function (i.e. homeostasis model of assessment of β-cell function). The present study shows for the first time that resveratrol improves insulin sensitivity in humans, which might be due to a resveratrol-induced decrease in oxidative stress that leads to a more efficient insulin signalling via the Akt pathway.

scholarly journals No decrease of the beta-cell mass in type 2 diabetic patients

Diabetes ◽  
2001 ◽  
Vol 50 (Supplement 1) ◽  
pp. S188-S188 ◽  
Author(s):  
Y. Guiot ◽  
C. Sempoux ◽  
P. Moulin ◽  
J. Rahier
Keyword(s):  
Beta Cell ◽  
Cell Mass ◽  
Beta Cell Mass ◽  
Diabetic Patients ◽  
Type 2 Diabetic Patients ◽  
Type 2 Diabetic

T1044 Ultrasonographic Fatty Pancreas Is Associated with β-Cell Dysfunction in Korean Type 2 Diabetic Patients

2009 ◽  
Vol 136 (5) ◽  
pp. A-487
Author(s):  
Seon-Young Park ◽  
Jin-Ook Chung ◽  
Kyoung-Won Yoon ◽  
Sung-Bum Cho ◽  
Wan-Sik Lee ◽  
...  
Keyword(s):  
Diabetic Patients ◽  
Β Cell ◽  
Type 2 Diabetic Patients ◽  
Cell Dysfunction ◽  
Fatty Pancreas ◽  
Korean Type ◽  
Type 2 Diabetic

scholarly journals Very Low–Calorie Diet Mimics the Early Beneficial Effect of Roux-en-Y Gastric Bypass on Insulin Sensitivity and β-Cell Function in Type 2 Diabetic Patients

Diabetes ◽  
2013 ◽  
Vol 62 (9) ◽  
pp. 3027-3032 ◽  
Author(s):  
Clifton Jackness ◽  
Wahida Karmally ◽  
Gerardo Febres ◽  
Irene M. Conwell ◽  
Leaque Ahmed ◽  
...  
Keyword(s):  
Cell Function ◽  
Diabetic Patients ◽  
Β Cell ◽  
Very Low Calorie Diet ◽  
Type 2 Diabetic Patients ◽  
Low Calorie Diet ◽  
Calorie Diet ◽  
Β Cell Function ◽  
Type 2 Diabetic

scholarly journals Decrement of postprandial insulin secretion determines the progressive nature of type-2 diabetes

2006 ◽  
Vol 155 (4) ◽  
pp. 615-622 ◽  
Author(s):  
Wan Sub Shim ◽  
Soo Kyung Kim ◽  
Hae Jin Kim ◽  
Eun Seok Kang ◽  
Chul Woo Ahn ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Insulin Secretion ◽  
Diabetic Patients ◽  
Β Cell ◽  
Type 2 Diabetic Patients ◽  
C Peptide ◽  
Duration Of Diabetes ◽  
Type 2 Diabetic ◽  
Postprandial Insulin

Objective: Type-2 diabetes is a progressive disease. However, little is known about whether decreased fasting or postprandial pancreatic β-cell responsiveness is more prominent with increased duration of diabetes. The aim of this study was to evaluate the relationship between insulin secretion both during fasting and 2 h postprandial, and the duration of diabetes in type-2 diabetic patients. Design: Cross-sectional clinical investigation. Methods: We conducted a meal tolerance test in 1466 type-2 diabetic patients and calculated fasting (M0) and postprandial (M1) β-cell responsiveness. Results: The fasting C-peptide, postprandial C-peptide, M0, and M1 values were lower, but HbA1c values were higher, in patients with diabetes duration > 10 years than those in other groups. There was no difference in the HbA1c levels according to the tertiles of their fasting C-peptide level. However, in a group of patients with highest postprandial C-peptide tertile, the HbA1c values were significantly lower than those in other groups. After adjustment of age, sex, and body mass index (BMI), the duration of diabetes was found to be negatively correlated with fasting C-peptide (γ = −0.102), postprandial C-peptide (γ = −0.356), M0 (γ = −0.263), and M1 (γ = −0.315; P < 0.01 respectively). After adjustment of age, sex, and BMI, HbA1c was found to be negatively correlated with postprandial C-peptide (γ = −0.264), M0 (γ = −0.379), and M1 (γ = −0.522), however, positively correlated with fasting C-peptide (γ = 0.105; P < 0.01 respectively). In stepwise multiple regression analysis, M0, M1, and homeostasis model assessment for insulin resistance (HOMA-IR) emerged as predictors of HbAlc after adjustment for age, sex, and BMI (R2 = 0.272, 0.080, and 0.056 respectively). Conclusions: With increasing duration of diabetes, the decrease of postprandial insulin secretion is becoming more prominent, and postprandial β-cell responsiveness may be a more important determinant for glycemic control than fasting β-cell responsiveness.

Physical training may enhance β-cell function in type 2 diabetes

2004 ◽  
Vol 287 (5) ◽  
pp. E1024-E1031 ◽  
Author(s):  
Flemming Dela ◽  
Michael E. von Linstow ◽  
Kári Joensen Mikines ◽  
Henrik Galbo
Keyword(s):  
Insulin Sensitivity ◽  
Cell Function ◽  
Diabetic Patients ◽  
Β Cell ◽  
Type 2 Diabetic Patients ◽  
C Peptide ◽  
Glucagon Test ◽  
Β Cell Function ◽  
Type 2 Diabetic

In healthy young subjects, training increases insulin sensitivity but decreases the capacity to secrete insulin. We studied whether training changes β-cell function in type 2 diabetic patients. Patients, stratified into “moderate” and “low” secretors according to individual C-peptide responses to an intravenous glucagon test, were randomly assigned to a training program [ergometer cycling 30–40 min/day, including at least 20 min at 75% maximum oxygen consumption (V̇o2 max), 5 days/wk for 3 mo] or a sedentary schedule. Before and after the intervention (16 h after last training bout), a sequential hyperglycemic (90 min at 11, 18, and 25 mM) clamp was performed. An intravenous bolus of 5 g of arginine was given at the end. Training increased V̇o2 max 17 ± 13% and decreased heart rate during submaximal exercise ( P < 0.05). During the 3 mo of sedentary lifestyle, insulin and C-peptide responses to the clamp procedures were unchanged in both moderate and low secretors. Likewise, no change in β-cell response was seen after training in the low secretors ( n = 5). In contrast, moderate secretors ( n = 9) showed significant increases in β-cell responses to 18 and 25 mM hyperglycemia and to arginine stimulation. Glucagon responses to arginine as well as measures of insulin sensitivity and Hb A1c levels were not altered by training. In conclusion, in type 2 diabetic patients, training may enhance β-cell function if the remaining secretory capacity is moderate but not if it is low. The improved β-cell function does not require changes in insulin sensitivity and Hb A1c concentration.

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