An Anthocyanin-Rich Mixed-Berry Intervention May Improve Insulin Sensitivity in a Randomized Trial of Overweight and Obese Adults

Evidence supports the beneficial effects of berries on glucoregulation, possibly related to flavonoid content, fiber content, or both. The purpose of this study was to assess the potential of mixed berries to improve insulin sensitivity and to identify the potential role of flavonoids and fiber. In a randomized cross-over trial with four treatment periods, overweight/obese men and women were fed a controlled 45% fat diet for one week prior to a meal-based glucose tolerance test. The same base diet was provided during each feeding period with the addition of one of four treatments: whole mixed berries, sugar matched mixed berry juice, sugar matched gelatin, and sugar/fiber matched gelatin. Subjects then completed a meal-based oral glucose tolerance test. Serum glucose, insulin and non-esterified fatty acids were not different between individual treatments. However, in a secondary analysis, the combined berry preparations resulted in a lower serum insulin area under the curve (difference of 0.15 ± 0.066 ln pmol min/mL, mean ± SE, p = 0.0228), compared to the combined gelatin treatments, while the difference for serum glucose did not quite meet statistical significance (difference of 0.17 ± 0.093 ln mg·min/dL, mean ± SE, p = 0.0738). These results suggest the potential for mixed berry preparations to improve post-prandial insulin response.

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167 EVIDENCE FOR A HYPERBOLIC RELATIONSHIP BETWEEN INSULIN SENSITIVITY AND THE INSULIN RESPONSE DERIVED FROM AN ORAL GLUCOSE TOLERANCE TEST

Journal of Investigative Medicine ◽

10.2310/6650.2005.00005.166 ◽

2005 ◽

Vol 53 (1) ◽

pp. S107.2-S107

Author(s):

K. M. Utzschneider ◽

R. L. Prigeon ◽

D. B. Carr ◽

J. Tong ◽

R. L. Hull ◽

...

Keyword(s):

Insulin Sensitivity ◽

Glucose Tolerance ◽

Oral Glucose Tolerance Test ◽

Glucose Tolerance Test ◽

Insulin Response ◽

Tolerance Test ◽

Oral Glucose ◽

Oral Glucose Tolerance

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Growth Hormone and Sex Steroid Effects on Serum Glucose, Insulin, and Lipid Concentrations in Healthy Older Women and Men

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2009-1275 ◽

2009 ◽

Vol 94 (10) ◽

pp. 3833-3841 ◽

Cited By ~ 16

Author(s):

Thomas Münzer ◽

S. Mitchell Harman ◽

John D. Sorkin ◽

Marc R. Blackman

Keyword(s):

Insulin Sensitivity ◽

Glucose Tolerance ◽

Ldl Cholesterol ◽

Glucose Tolerance Test ◽

Tolerance Test ◽

Serum Glucose ◽

Sex Steroid ◽

Oral Glucose ◽

Older Individuals ◽

Beneficial Effects

Context: With aging, GH, IGF-I, and sex steroid concentrations and glucose tolerance decrease, and body fat and serum lipids increase. Objective: The aim of the study was to assess GH and/or sex steroid administration effects on serum glucose, insulin, insulin sensitivity, and lipids in older individuals. Design: A double-masked, 2 × 2 factorial, placebo-controlled, double-dummy design was used for the study. Intervention: GH and/or sex steroid [transdermal estradiol plus oral medroxyprogesterone acetate in women (HRT); testosterone enanthate (T) in men] were administered for 6 months. Participants: Healthy, community-dwelling women (n = 57) and men (n = 74) ages 65–88 yr (mean, 72 yr) participated in the study. Main Outcome Measures: We measured serum glucose, insulin, and insulin sensitivity [quantitative insulin sensitivity check index (QUICKI) and insulin sensitivity index (ISI)] before and during an oral glucose tolerance test and lipid profiles. Results: In women, GH did not alter oral glucose tolerance test 120 min or 2-h area under the curve (AUC) glucose values, but it increased 120 min insulin and AUC insulin. There were no significant effects of HRT or GH+HRT. ISI and QUICKI decreased after GH. In men, GH increased 120 min and AUC glucose and insulin AUC. GH+T increased 120 min glucose and glucose and insulin AUCs. T alone did not affect glucose or insulin. ISI decreased after GH and GH+T, whereas QUICKI decreased after GH. GH in women and men and GH+T in men decreased QUICKI by 4 wk. In women, HRT decreased total cholesterol and low-density lipoprotein (LDL)-cholesterol, and GH decreased LDL-cholesterol. In men, total cholesterol decreased after T and GH+T. LDL-cholesterol decreased after GH and GH+T. GH increased serum triglycerides. Conclusions: GH administration to healthy older individuals for 6 months increased insulin resistance with moderately beneficial effects on lipids. Chronic GH administration to healthy older individuals increases insulin resistance with moderately beneficial effects on lipids.

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Oral glucose tolerance test and insulin sensitivity in low insulin responders

Acta Endocrinologica ◽

10.1530/acta.0.1040077 ◽

1983 ◽

Vol 104 (1) ◽

pp. 77-84 ◽

Cited By ~ 9

Author(s):

A. Wajngot ◽

R. Luft ◽

S. Efendić

Keyword(s):

Insulin Sensitivity ◽

Glucose Tolerance ◽

Glucose Tolerance Test ◽

Fasting Blood Glucose ◽

Insulin Response ◽

Tolerance Test ◽

Oral Glucose ◽

Infusion Test ◽

Glucose Infusion Test ◽

Low Insulin Response

Abstract. Oral and iv glucose tolerance, insulin response to iv and oral glucose load as well as insulin sensitivity were evaluated in 58 'low insulin responders'. They were selected from a group of 226 healthy subjects with normal fasting blood glucose and normal iv glucose tolerance test on the basis of a low insulin response during a standardized glucose infusion test (GIT). The insulin response to GIT was analysed by parameter identification in a mathematical model (parameter KI). Insulin sensitivity was also measured by computer analysis of GIT (parameter KG) and, in a limited group of subjects, by a somatostatin infusion test. Thirty-three low insulin responders had normal OGTT, whereas 5 demonstrated borderline-1, 16 borderline-2, and 4 decreased OGTT. The first group of subjects demonstrated normal or enhanced insulin sensitivity. Borderline and decreased OGTT, in most instances, was accompanied by decreased insulin sensitivity, implying that a subgroup of low insulin responders exhibited signs of both impaired insulin response to glucose and insulin resistance. Since these defects characterize manifest type-2 diabetes, these subjects possibly may run a high risk to develop this type of diabetes. On the other hand, low insulin response in combination with increased insulin sensitivity may reflect adaptation of the secretory capacity of B-cells to the need of insulin.

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Assay-dependent variability of serum insulin levels during oral glucose tolerance test: influence on reference intervals for insulin and on cut-off values for insulin sensitivity indices

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm.2008.020 ◽

2008 ◽

Vol 46 (2) ◽

Cited By ~ 10

Author(s):

Maria Werner ◽

Anke Tönjes ◽

Michael Stumvoll ◽

Joachim Thiery ◽

Jürgen Kratzsch

Keyword(s):

Insulin Sensitivity ◽

Glucose Tolerance ◽

Oral Glucose Tolerance Test ◽

Glucose Tolerance Test ◽

Serum Insulin ◽

Tolerance Test ◽

Reference Intervals ◽

Oral Glucose ◽

Oral Glucose Tolerance ◽

Sensitivity Indices

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Antidepressant Effects on Insulin Sensitivity and Proinflammatory Cytokines in the Depressed Males

Mediators of Inflammation ◽

10.1155/2010/573594 ◽

2010 ◽

Vol 2010 ◽

pp. 1-7 ◽

Cited By ~ 26

Author(s):

Yi-Chyan Chen ◽

Wei-Win Lin ◽

Yu-Jung Chen ◽

Wei-Chung Mao ◽

Yi-Jen Hung

Keyword(s):

Insulin Sensitivity ◽

Glucose Tolerance ◽

Rating Scale ◽

Glucose Tolerance Test ◽

Antidepressant Treatment ◽

Insulin Response ◽

Tolerance Test ◽

Oral Glucose ◽

Intravenous Glucose ◽

Testing Procedures

Growing evidence suggests that mood disorder is associated with insulin resistance and inflammation. Thus the effects of antidepressants on insulin sensitivity and proinflammatory responses will be a crucial issue for depression treatment. In this study, we enrolled 43 non-diabetic young depressed males and adapted standard testing procedures to assess glucose metabolism during 4-week hospitalization. Before and after the 4-week antidepressant treatment, participants underwent oral glucose tolerance test (OGTT) and frequently sampled intravenous glucose tolerance test (FSIGT). Insulin sensitivity (SI), glucose effectiveness (SG), acute insulin response, and disposition index (DI) were estimated using the minimal model method. The plasma levels of C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-α(TNF-α), and adiponectin were measured. The Hamilton depression rating scale (HAM-D) total scores were reduced significantly during the course of treatment. There were no significant changes in the parameters ofSI,SG, and DI. Compared to drug naïve status, the level of plasma IL-6 was significantly elevated (0.77to1.30 pg/ml;P=.001) after antidepressant therapy. However, the concentrations of CRP, TNF-α, and adiponectin showed no differences during the course of treatment. The results suggest that antidepressants may promote stimulatory effect on the IL-6 production in the early stage of antidepressant treatment.

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First-phase insulin response (FPIR) to intravenous glucose tolerance test (IVGTT), insulin sensitivity and long-term follow-up in ?- transfusion-dependent thalassemia (TDT) normoglycemic patients with reduced insulin secretion to oral glucose tolerance t

Mediterranean Journal of Hematology and Infectious Diseases ◽

10.4084/mjhid.2021.021 ◽

2021 ◽

Vol 13 (1) ◽

pp. e2021021

Author(s):

Vincenzo De Sanctis

Keyword(s):

Insulin Sensitivity ◽

Glucose Tolerance ◽

Glucose Tolerance Test ◽

Insulin Response ◽

Tolerance Test ◽

Intravenous Glucose Tolerance Test ◽

Oral Glucose ◽

Sensitivity Index ◽

Intravenous Glucose

Summary. Objective: To study the function of the endocrine pancreas in transfusion-dependent ?-thalassemia (?-TDT) patients with normal oral glucose tolerance test (OGTT) and hypoinsulinemia. Patients and methods: Seven ?-TDT patients (mean age 22.4 ± 4.2 years) with normal glucose tolerance test (NGT) and poor insulin response (hypoinsulinemia) to OGTT, not associated with ?-cell autoimmunity, were referred for a second opinion to an Italian Centre, part of the International Network of Clinicians for Endocrinopathies in Thalassemia and Adolescence Medicine (ICET-A). In this pilot study, the first-phase insulin response (FPIR), expressed as the sum of 1 and 3 minutes insulin, of ?-TDT patients to intravenous glucose tolerance test (IVGTT), was tested. Moreover, the long-term natural history was followed prospectively using an annual OGTT, with the aim of detecting any abnormality of glucose metabolism. Results: The FPIR value was between the 1st and 3rd percentile in two patients and between the 3rd and 10th percentile in five. After 43 ± 26 months (range 11 - 80 months) of follow-up, 2 patients developed impaired glucose tolerance (IGT), 3 both IGT and impaired fasting glucose (IFG) and two overt diabetes mellitus (DM). Interestingly, the patients who developed DM had, at baseline the lowest value of insulinogenic index (IGI, 0.08 and 0.25), defined as the ratio of the increment of plasma insulin to plasma glucose during the first 30 minutes after OGTT. Moreover, a significant correlation was found between the IGI at baseline and at follow-up in the patients who developed IGT with or without IFG (R= 0.927; P: 0.023). A significant reduction of Matsuda insulin sensitivity index (ISIM) and Insulin Secretion-Sensitivity Index-2 (ISSI-2) was documented in the study cohort at diagnosis of IFG, IGT and DM. There was a significant inverse correlation between ISSI-2 and area under the curve of plasma glucose (AUC-PG). Conclusions: These data demonstrated, for the first time, a progressive deterioration in glucose homeostasis in ?-TDT subjects with NGT and hypoinsulinemia. Thus, we consider that variations of insulin sensitivity could possibly have an impact on glucose tolerance in adult patients with TDT. Further investigations should focus on factors that might positively influence insulin sensitivity, including nutrition, drugs and physical activity.

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Effect of breakfast fat content on glucose tolerance and risk factors of atherosclerosis and thrombosis

British Journal Of Nutrition ◽

10.1017/s000711459800138x ◽

1998 ◽

Vol 80 (4) ◽

pp. 323-331 ◽

Cited By ~ 1

Author(s):

David L. Frape ◽

Norman R. Williams ◽

Jayshri Rajput-Williams ◽

B. W. Maitland ◽

A. J. Scriven ◽

...

Keyword(s):

Glucose Tolerance ◽

Thrombus Formation ◽

Serum Insulin ◽

Lipid Fraction ◽

Tolerance Test ◽

Serum Glucose ◽

Oral Glucose ◽

Significant Treatment ◽

Treatment Allocation ◽

Insulin Responses

Twenty-four middle-aged healthy men were given a low-fat high-carbohydrate (5.5 g fat; L), or a moderately-fatty, (25.7 g fat; M) breakfast of similar energy contents for 28 d. Other meals were under less control. An oral glucose tolerance test (OGTT) was given at 09.00 hours on day 1 before treatment allocation and at 13.30 hours on day 29. There were no significant treatment differences in fasting serum values, either on day 1 or at the termination of treatments on day 29. The following was observed on day 29: (1) the M breakfast led to higher OGTT C-peptide responses and higher areas under the curves (AUC) of OGTT serum glucose and insulin responses compared with the OGTT responses to the L breakfast (P< 0.05); (2) treatment M failed to prevent OGTT glycosuria, eliminated with treatment L; (3) serum non-esterified fatty acid (NEFA) AUC was 59% lower with treatment L than with treatment M, between 09.00 and 13.20 hours (P<0.0001), and lower with treatment L than with treatment M during the OGTT (P= 0.005); (4) serum triacylglycerol (TAG) concentrations were similar for both treatments, especially during the morning, but their origins were different during the afternoon OGTT when the Svedberg flotation unit 20–400 lipid fraction was higher with treatment L than with treatment M (P= 0.016); plasma apolipoprotein B-48 level with treatment M was not significantly greater than that with treatment L (P= 0.086); (5) plasma tissue plasminogen-activator activity increased after breakfast with treatment L (P= 0.0008), but not with treatment M (P= 0.80). Waist:hip circumference was positively correlated with serum insulin and glucose AUC and with fasting LDL-cholesterol. Waist:hip circumference and serum TAG and insulin AUC were correlated with factors of thrombus formation; and the OGTT NEFA and glucose AUC were correlated. A small difference in fat intake at breakfast has a large influence on circulating diurnal NEFA concentration, which it is concluded influences adversely glucose tolerance up to 6 h later.

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