CYBERMED LIFE - ORGANIC  & NATURAL LIVING

Insulin Resistance

Insulin resistance (IR) is a pathological condition in which cells fail to respond normally to the hormone insulin. The body produces insulin when glucose starts to be released into the bloodstream from the digestion of carbohydrates (primarily) in the diet. Under normal conditions of insulin reactivity, this insulin response triggers glucose being taken into body cells, to be used for energy, and inhibits the body from using fat for energy, thereby causing the concentration of glucose in the blood to decrease as a result, staying within the normal range even when a large amount of carbohydrates is consumed. During insulin resistance, however, excess glucose is not sufficiently absorbed by cells even in the presence of insulin, thereby causing an increase in the level of blood sugar.

  • A 12-week aerobic exercise program reduces hepatic fat accumulation and insulin resistance in obese, Hispanic adolescents📎

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    Abstract Title:

    A 12-week aerobic exercise program reduces hepatic fat accumulation and insulin resistance in obese, Hispanic adolescents.

    Abstract Source:

    Obesity (Silver Spring). 2010 Feb ;18(2):384-90. Epub 2009 Aug 20. PMID: 19696755

    Abstract Author(s):

    Gert-Jan van der Heijden, Zhiyue J Wang, Zili D Chu, Pieter J J Sauer, Morey W Haymond, Luisa M Rodriguez, Agneta L Sunehag

    Article Affiliation:

    Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA.

    Abstract:

    The rise in obesity-related morbidity in children and adolescents requires urgent prevention and treatment strategies. Currently, only limited data are available on the effects of exercise programs on insulin resistance, and visceral, hepatic, and intramyocellular fat accumulation. We hypothesized that a 12-week controlled aerobic exercise program without weight loss reduces visceral, hepatic, and intramyocellular fat content and decreases insulin resistance in sedentary Hispanic adolescents. Twenty-nine postpubertal (Tanner stage IV and V), Hispanic adolescents, 15 obese (7 boys, 8 girls; 15.6 +/- 0.4 years; 33.7 +/- 1.1 kg/m(2); 38.3 +/- 1.5% body fat) and 14 lean (10 boys, 4 girls; 15.1 +/- 0.3 years; 20.6 +/- 0.8 kg/m(2); 18.9 +/- 1.5% body fat), completed a 12-week aerobic exercise program (4 x 30 min/week at>or =70% of peak oxygen consumption (VO(2)peak)). Measurements of cardiovascular fitness, visceral, hepatic, and intramyocellular fat content (magnetic resonance imaging (MRI)/magnetic resonance spectroscopy (MRS)), and insulin resistance were obtained at baseline and postexercise. In both groups, fitness increased (obese: 13 +/- 2%, lean: 16 +/- 4%; both P<0.01). In obese participants, intramyocellular fat remained unchanged, whereas hepatic fat content decreased from 8.9 +/- 3.2 to 5.6 +/- 1.8%; P<0.05 and visceral fat content from 54.7 +/- 6.0 to 49.6 +/- 5.5 cm(2); P<0.05. Insulin resistance decreased indicated by decreased fasting insulin (21.8 +/- 2.7 to 18.2 +/- 2.4 microU/ml; P<0.01) and homeostasis model assessment of insulin resistance (HOMA(IR)) (4.9 +/- 0.7 to 4.1 +/- 0.6; P<0.01). The decrease in visceral fat correlated with the decrease in fasting insulin (R(2) = 0.40; P<0.05). No significant changes were observed in any parameter in lean participants except a small increase in lean body mass (LBM). Thus, a controlled aerobic exercise program, without weight loss, reduced hepatic and visceral fat accumulation, and decreased insulin resistance in obese adolescents.

  • A MUFA-rich diet improves posprandial glucose, lipid and GLP-1 responses in insulin-resistant subjects.

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    Abstract Title:

    A MUFA-rich diet improves posprandial glucose, lipid and GLP-1 responses in insulin-resistant subjects.

    Abstract Source:

    J Am Coll Nutr. 2007 Oct;26(5):434-44. PMID: 17914131

    Abstract Author(s):

    Juan A Paniagua, Angel Gallego de la Sacristana, Esther Sánchez, Inmaculada Romero, Antonio Vidal-Puig, Francisco J Berral, Antonio Escribano, Maria José Moyano, Pablo Peréz-Martinez, José López-Miranda, Francisco Pérez-Jiménez

    Article Affiliation:

    Lipids and Atherosclerosis Research Unit, University Hospital Reina Sofía, Córdoba, Spain. This email address is being protected from spambots. You need JavaScript enabled to view it.

    Abstract:

    OBJECTIVE:To study the effects of three weight-maintenance diets with different macronutrient composition on carbohydrate, lipid metabolism, insulin and incretin levels in insulin-resistant subjects.

    METHODS:A prospective study was performed in eleven (7 W, 4 M) offspring of obese and type 2 diabetes patients. Subjects had a BMI>25 Kg/m2, waist circumference (men/women)>102/88, HBA1c<6.5% and were regarded as insulin-resistant after an OGTT (Matsuda ISIm<4). They were randomly divided into three groups and underwent three dietary periods each of 28 days in a crossover design: a) diet high in saturated fat (SAT), b) diet rich in monounsaturated fat (MUFA; Mediterranean diet) and c) diet rich in carbohydrate (CHO).

    RESULTS:Body weight and resting energy expenditure did not changed during the three dietary periods. Fasting serum glucose concentrations fell during MUFA-rich and CHO-rich diets compared with high-SAT diets (5.02 +/- 0.1, 5.03 +/- 0.1, 5.50 +/- 0.2 mmol/L, respectively. Anova<0.05). The MUFA-rich diet improved insulin sensitivity, as indicated by lower homeostasis model analysis-insulin resistance (HOMA-ir), compared with CHO-rich and high-SAT diets (2.32 +/- 0.3, 2.52 +/- 0.4, 2.72 +/- 0.4, respectively, Anova<0.01). After a MUFA-rich and high-SAT breakfasts (443 kcal) the postprandial integrated area under curve (AUC) of glucose and insulin were lowered compared with isocaloric CHO-rich breakfast (7.8 +/- 1.3, 5.84 +/- 1.2, 11.9 +/- 2.7 mmol . 180 min/L, Anova<0.05; and 1004 +/- 147, 1253 +/- 140, 2667 +/- 329 pmol . 180 min/L, Anova<0.01, respectively); while the integrated glucagon-like peptide-1 response increased with MUFA and SAT breakfasts compared with isocaloric CHO-rich meals (4.22 +/- 0.7, 4.34 +/- 1.1, 1.85 +/- 1.1, respectively, Anova<0.05). Fasting and postprandial HDL cholesterol concentrations rose with MUFA-rich diets, and the AUCs of triacylglycerol fell with the CHO-rich diet. Similarly fasting proinsulin (PI) concentration fell, while stimulated ratio PI/I was not changed by MUFA-rich diet.

    CONCLUSIONS:Weight maintenance with a MUFA-rich diet improves HOMA-ir and fasting proinsulin levels in insulin-resistant subjects. Ingestion of a virgin olive oil-based breakfast decreased postprandial glucose and insulin concentrations, and increased HDL-C and GLP-1 concentrations as compared with CHO-rich diet.

  • A plant-based diet for the prevention and treatment of type 2 diabetes📎

    Abstract Title:

    A plant-based diet for the prevention and treatment of type 2 diabetes.

    Abstract Source:

    J Geriatr Cardiol. 2017 May ;14(5):342-354. PMID: 28630614

    Abstract Author(s):

    Michelle McMacken, Sapana Shah

    Article Affiliation:

    Michelle McMacken

    Abstract:

    The prevalence of type 2 diabetes is rising worldwide, especially in older adults. Diet and lifestyle, particularly plant-based diets, are effective tools for type 2 diabetes prevention and management. Plant-based diets are eating patterns that emphasize legumes, whole grains, vegetables, fruits, nuts, and seeds and discourage most or all animal products. Cohort studies strongly support the role of plant-based diets, and food and nutrient components of plant-based diets, in reducing the risk of type 2 diabetes. Evidence from observational and interventional studies demonstrates the benefits of plant-based diets in treating type 2 diabetes and reducing key diabetes-related macrovascular and microvascular complications. Optimal macronutrient ratios for preventing and treating type 2 diabetes are controversial; the focus should instead be on eating patterns and actual foods. However, the evidence does suggest that the type and source of carbohydrate (unrefined versus refined), fats (monounsaturated and polyunsaturated versus saturated and trans), and protein (plant versus animal) play a major role in the prevention and management of type 2 diabetes. Multiple potential mechanisms underlie the benefits of a plant-based diet in ameliorating insulin resistance, including promotion of a healthy body weight, increases in fiber and phytonutrients, food-microbiome interactions, and decreases in saturated fat, advanced glycation endproducts, nitrosamines, and heme iron.

  • A randomized controlled trial of Kung Fu training for metabolic health in overweight/obese adolescents: the "martial fitness" study.

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    Abstract Title:

    A randomized controlled trial of Kung Fu training for metabolic health in overweight/obese adolescents: the "martial fitness" study.

    Abstract Source:

    J Pediatr Endocrinol Metab. 2009 Jul;22(7):595-607. PMID: 19774841

    Abstract Author(s):

    Tracey W Tsang, Michael Kohn, Chin Moi Chow, Maria Fiatarone Singh

    Abstract:

    Twenty overweight/obese adolescents underwent six months of Kung Fu or placebo (Tai Chi) training, 3x.wk(-1). Outcomes included fasting insulin and insulin resistance, lipids, glucose and HbA(1c), and C-reactive protein (CRP). CRP decreased significantly (p = 0.03) in both groups over time at six months. Although insulin sensitivity did not change, HbA(1c) tended to decrease over time (p = 0.09), again with no group difference (p = 0.60). Reduced CRP was related to increased upper body strength (p = 0.01). Increased lean body mass was related to reductions in HbA(1c), insulin resistance, triglycerides, and total cholesterol. Improvements in lean body mass appear to have a potential role in favorable metabolic outcomes, independent of changes in fat mass. Further research in this area is warranted before definite conclusions can be drawn about the efficacy of martial arts training for metabolic outcomes in this cohort.

  • Acupuncture Alters Expression of Insulin Signaling Related Molecules and Improves Insulin Resistance in OLETF Rats. 📎

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    Abstract Title:

    Acupuncture Alters Expression of Insulin Signaling Related Molecules and Improves Insulin Resistance in OLETF Rats.

    Abstract Source:

    Evid Based Complement Alternat Med. 2016 ;2016:9651592. Epub 2016 Aug 22. PMID: 27738449

    Abstract Author(s):

    Xin-Yu Huang, Liang Zhang, Jian Sun, Neng-Gui Xu, Wei Yi

    Article Affiliation:

    Xin-Yu Huang

    Abstract:

    To determine effect of acupuncture on insulin resistance in Otsuka Long-Evans Tokushima Fatty (OLETF) rats and to evaluate expression of insulin signaling components. Rats were divided into three groups: Sprague-Dawley (SD) rats, OLETF rats, and acupuncture+OLETF rats. Acupuncture was subcutaneously applied to Neiguan (PC6), Zusanli (ST36), and Sanyinjiao (SP6); in contrast, acupuncture to Shenshu (BL23) was administered perpendicularly. For Neiguan (PC6) and Zusanli (ST36), needles were connected to an electroacupuncture (EA) apparatus. Fasting blood glucose (FPG) was measured by glucose oxidase method. Plasma fasting insulin (FINS) and serum C peptide (C-P) were determined by ELISA. Protein and mRNA expressions of insulin signaling molecules were determined by Western blot and real-time RT-PCR, respectively. OLETF rats exhibit increased levels of FPG, FINS, C-P, and homeostasis model assessment-estimated insulin resistance (HOMA-IR), which were effectively decreased by acupuncture treatment. mRNA expressions of several insulin signaling related molecules IRS1, IRS2, Akt2, aPKCζ, and GLUT4 were decreased in OLETF rats compared to SD controls. Expression of these molecules was restored back to normal levels upon acupuncture administration. PI3K-p85α was increased in OLETF rats; this increase was also reversed by acupuncture treatment. Acupuncture improves insulin resistance in OLETF rats, possibly via regulating expression of key insulin signaling related molecules.

  • Aerobic exercise increases peripheral and hepatic insulin sensitivity in sedentary adolescents📎

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    Abstract Title:

    Aerobic exercise increases peripheral and hepatic insulin sensitivity in sedentary adolescents.

    Abstract Source:

    J Clin Endocrinol Metab. 2009 Nov ;94(11):4292-9. Epub 2009 Oct 6. PMID: 19808855

    Abstract Author(s):

    Gert-Jan van der Heijden, Gianna Toffolo, Erica Manesso, Pieter J J Sauer, Agneta L Sunehag

    Article Affiliation:

    Department of Pediatrics (G.-J.v.d.H., A.L.S.), Baylor College of Medicine, Houston, Texas 77030, USA.

    Abstract:

    CONTEXT:Data are limited on the effects of controlled aerobic exercise programs (without weight loss) on insulin sensitivity and glucose metabolism in children and adolescents.

    OBJECTIVE:To determine whether a controlled aerobic exercise program (without weight loss) improves peripheral and hepatic insulin sensitivity and affects glucose production (GPR), gluconeogenesis and glycogenolysis in sedentary lean and obese Hispanic adolescents.

    PATIENTS AND DESIGN:Twenty-nine post-pubertal adolescents (14 lean: 15.1 +/- 0.3 y; 20.6 +/- 0.8 kg/m(2); 18.9+/-1.5% body fat and 15 obese: 15.6 +/- 0.4 y; 33.2 +/- 0.9 kg/m(2); 38.4 +/- 1.4% body fat) (mean +/- SE), completed a 12 wk aerobic exercise program (4 x 30 min/week at>or=70% of VO(2) peak). Peripheral and hepatic insulin sensitivity and glucose kinetics were quantified using GCMS pre- and post-exercise.

    RESULTS:No weight loss occurred. Lean and obese participants complied well with the program ( approximately 90% of the exercise sessions attended, resulting in approximately 15% increase in fitness in both groups). Peripheral and hepatic insulin sensitivity were higher in lean than obese adolescents but increased in both groups; peripheral insulin sensitivity by 35 +/- 14% (lean) (p<0.05) and 59 +/- 19% (obese) (p<0.01) and hepatic insulin sensitivity by 19 +/- 7% (lean) (p<0.05) and 23 +/- 4% (obese) (p<0.01). GPR, gluconeogenesis and glycogenolysis did not differ between the groups. GPR decreased slightly, 3 +/- 1% (lean) (p<0.05) and 4 +/- 1% (obese) (p<0.01). Gluconeogenesis remained unchanged, while glycogenolysis decreased slightly in the obese group (p<0.01).

    CONCLUSION:This well accepted aerobic exercise program, without weight loss, is a promising strategy to improve peripheral and hepatic insulin sensitivity in lean and obese sedentary adolescents. The small decrease in GPR is probably of limited clinical relevance.

  • Ameliorative potential of acupressure on gestational diabetes mellitus: A randomized controlled trial.

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    Abstract Title:

    Ameliorative potential of acupressure on gestational diabetes mellitus: A randomized controlled trial.

    Abstract Source:

    J Complement Integr Med. 2018 Jun 21 ;16(1). Epub 2018 Jun 21. PMID: 29927746

    Abstract Author(s):

    Fayiz F El-Shamy, Sanad S El-Kholy, Mahmoud Labib, Ahmed M Kabel

    Article Affiliation:

    Fayiz F El-Shamy

    Abstract:

    Background and aim Gestational diabetes mellitus (GDM) poses a threat to the mother and child. The aim of this study was to examine the effect of acupressure on the glycemic control and insulin requirement of GDM females. Materials and methods Thirty GDM female patients were randomized to either the study group (SG; n=15), which was treated with acupressure and the standard antenatal care, or the control group (CG; n=15), which was treated with the standard antenatal care. Fasting and 2-h post-prandial blood glucose levels, requirement for insulin and insulin resistance were measured at 24 and 36 weeks' gestation (WG). Also, neonatal outcomes were registered at delivery. Results The pre intervention showed no statistically significant differences between SG and CG for baseline characteristics of participants (p>0.05). Within group analyses, after 12 weeks intervention had shown that 75 g oral glucose tolerance test (OGTT), insulin resistance, number of required insulin and measure of utilized insulin were significantly reduced (p<0.05), with significant increase in body mass index (BMI) (p<0.05) in both groups. All outcome measures were not significantly changed (p>0.05) between both groups at 24 and 36 WG. No significant differences (p>0.05) in pregnancy and neonatal outcomes between both groups at labor. Conclusions Acupressure may help to reduce gestational diabetes or insulin treatment for overweight female patients with GDM.

  • Anti-inflammatory effects of vitamin D and resistance training in men with type 2 diabetes mellitus and vitamin D deficiency: a randomized, double-blinded, placebo-controlled clinical trial.

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    Abstract Title:

    Anti-inflammatory effects of vitamin D and resistance training in men with type 2 diabetes mellitus and vitamin D deficiency: a randomized, double-blinded, placebo-controlled clinical trial.

    Abstract Source:

    J Diabetes Metab Disord. 2019 Dec ;18(2):323-331. Epub 2019 Jun 24. PMID: 31890657

    Abstract Author(s):

    Ali Dadrass, Khalid Mohamadzadeh Salamat, Kamaladdin Hamidi, Kamal Azizbeigi

    Article Affiliation:

    Ali Dadrass

    Abstract:

    Objectives:The present study aimed to investigate the anti-inflammatory effects of vitamin D and resistance training in men with type 2 diabetes mellitus and vitamin D deficiency.

    Design:This study was a randomized, placebo-controlled, double-blinded clinical trial.: IRCT20190204042621N1.

    Participants:Forty-eight patients with type 2 diabetes aged 40-65 (from a total of 52 volunteers in Ardabil diabetes clinic) were randomly assigned to either the vitamin D supplementation with resistance training group (VD + RT: = 12), the resistance training group (RT: = 12), the vitamin D supplementation group (VD: = 12), or the control group (CON: = 12).

    Intervention:The subjects in VD group took vitamin D supplements at 50000 IU per 2 weeks for 3 months; the subjects in RT group exercised 3 times per week for 12 weeks; and the subjects in VD + RT group participated in both treatments. Subjects in CON group were asked to maintain normal daily life pattern for the duration of the study.

    Measurements:Serum Interleukin-6 (IL-6), Tumor Necrosis Factor-alpha (TNF-α) and C-reactive protein (CRP) levels were determined at pre and post-test and the data were compared among the four groups and between two tests (4 × 2) using two-way ANOVA with repeated measures.

    Results:IL-6 decreased significantly ( = 0.001) in all groups (VD + RT = % -71.73, RT = % -65.85, VD = % -61.70). TNF-α decreased significantly ( = 0.001) in VD + RT (% -44.90) and RT (% -40) groups. CRP showed no significant change in any group ( > 0.05).

    Conclusion:Results demonstrated that vitamin D supplementation in addition to resistance training had positive effects on some inflammatory markers in T2D and vitamin D deficient men. Vitamin D supplementation was especially effective when it was complemented with exercise training.

  • Ascorbic acid supplementation improves skeletal muscle oxidative stress and insulin sensitivity in people with type 2 diabetes: Findings of a randomized controlled study.

    Abstract Title:

    Ascorbic acid supplementation improves skeletal muscle oxidative stress and insulin sensitivity in people with type 2 diabetes: Findings of a randomized controlled study.

    Abstract Source:

    Free Radic Biol Med. 2016 Jan 13. Epub 2016 Jan 13. PMID: 26774673

    Abstract Author(s):

    Shaun A Mason, Paul A Della Gatta, Rod J Snow, Aaron P Russell, Glenn D Wadley

    Article Affiliation:

    Shaun A Mason

    Abstract:

    AIM/HYPOTHESIS:Skeletal muscle insulin resistance and oxidative stress are characteristic metabolic disturbances in people with type 2 diabetes. Studies in insulin resistant rodents show an improvement in skeletal muscle insulin sensitivity and oxidative stress following antioxidant supplementation. We therefore investigated the potential ameliorative effects of antioxidant ascorbic acid (AA) supplementation on skeletal muscle insulin sensitivity and oxidative stress in people with type 2 diabetes.

    METHODS:Participants with stable glucose control commenced a randomized cross-over study involving four months of AA (2×500mg/day) or placebo supplementation. Insulin sensitivity was assessed using a hyperinsulinaemic, euglycaemic clamp coupled with infusion of 6,6-D2 glucose. Muscle biopsies were measured for AA concentration and oxidative stress markers that included basal measures (2',7'-dichlorofluorescin [DCFH] oxidation, ratio of reduced-to-oxidized glutathione [GSH/GSSG] and F2-Isoprostanes) and insulin-stimulated measures (DCFH oxidation). Antioxidant concentrations, citrate synthase activity and protein abundances of sodium-dependent vitamin C transporter 2 (SVCT2), total Akt and phosphorylated Akt (ser473) were also measured in muscle samples.

    RESULTS:AA supplementation significantly increased insulin-mediated glucose disposal (delta rate of glucose disappearance;∆Rd) (p=0.009), peripheral insulin-sensitivity index (p=0.046), skeletal muscle AA concentration (p=0.017) and muscle SVCT2 protein expression (p=0.008); but significantly decreased skeletal muscle DCFH oxidation during hyperinsulinaemia (p=0.007) when compared with placebo. Total superoxide dismutase activity was also lower following AA supplementation when compared with placebo (p=0.006). Basal oxidative stress markers, citrate synthase activity, endogenous glucose production, HbA1C and muscle Akt expression were not significantly altered by AA supplementation.

    CONCLUSIONS/INTERPRETATION:In summary, oral AA supplementation ameliorates skeletal muscle oxidative stress during hyperinsulinaemia and improves insulin-mediated glucose disposal in people with type 2 diabetes. Findings implicate AA supplementation as a potentially inexpensive, convenient, and effective adjunct therapy in the treatment of insulin resistance in people with type 2 diabetes.

  • Attenuation of fructose-induced hypertension in rats by exercise training📎

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    Abstract Title:

    Attenuation of fructose-induced hypertension in rats by exercise training.

    Abstract Source:

    Hypertension. 1988 Aug;12(2):129-32. PMID: 3410522

    Abstract Author(s):

    G M Reaven, H Ho, B B Hoffman

    Article Affiliation:

    Department of Medicine, Stanford University School of Medicine, Palo Alto, CA.

    Abstract:

    This study was initiated to see if the insulin resistance, hyperinsulinemia, and hypertension that follow feeding normotensive Sprague-Dawley rats a fructose-rich diet could be prevented by letting rats run spontaneously in exercise wheel cages. Blood pressure in sedentary rats increased from (mean +/- SEM) 125 +/- 2 to 148 +/- 3 mm Hg in response to 2 weeks of a high fructose diet, and this increment was significantly (p less than 0.001) attenuated in exercising rats (from 121 +/- 1 to 131 +/- 2 mm Hg). In addition, mean (+/- SEM) plasma insulin concentration was lower in fructose-fed rats allowed to run spontaneously (44 +/- 2 vs 62 +/- 5 microU/ml; p less than 0.01). Finally, resistance to insulin-stimulated glucose uptake was assessed by determining the steady state plasma glucose response to a continuous glucose and exogenous insulin infusion during a period in which endogenous insulin secretion was suppressed. The results of these studies indicated that the mean (+/- SEM) steady state plasma glucose concentration was significantly lower in the exercise-trained rats (127 +/- 5 vs 168 +/- 6 mg/dl; p less than 0.001), despite the fact that the steady state plasma insulin levels were also lower in rats allowed to run spontaneously (75 +/- 4 vs 90 +/- 5 microU/ml; p less than 0.05). Thus, the ability of exercise-trained rats to stimulate glucose disposal was enhanced as compared with that of sedentary rats fed the same fructose-rich diet. These data demonstrate that the insulin resistance, hyperinsulinemia, and hypertension produced in normotensive rats by feeding them a high fructose diet can be attenuated if rats are allowed to run spontaneously.(ABSTRACT TRUNCATED AT 250 WORDS)

  • Beneficial effects of dietary restriction in type 2 diabetic rats: the role of adipokines on inflammation and insulin resistance. 📎

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    Abstract Title:

    Beneficial effects of dietary restriction in type 2 diabetic rats: the role of adipokines on inflammation and insulin resistance.

    Abstract Source:

    Br J Nutr. 2010 Jul;104(1):76-82. Epub 2010 Feb 24. PMID: 20178670

    Abstract Author(s):

    Joana Crisóstomo, Lisa Rodrigues, Paulo Matafome, Carmen Amaral, Elsa Nunes, Teresa Louro, Pedro Monteiro, Raquel Seiça

    Article Affiliation:

    Faculty of Medicine, Institute of Physiology, University of Coimbra, Coimbra, Portugal. This email address is being protected from spambots. You need JavaScript enabled to view it.

    Abstract:

    Inflammation plays an important role in diabetes mellitus and its complications. In this context, the negative cross-talk between adipose tissue and skeletal muscle leads to disturbances in muscle cell insulin signalling and induces insulin resistance. Because several studies have shown that energy restriction brings some benefits to diabetes, the aim of the present study was to evaluate the effects of dietary restriction on systemic and skeletal muscle inflammatory biomarkers, such C-reactive protein, adipokines and cytokines, and in insulin resistance in Goto-Kakizaki rats. This is an animal model of spontaneous non-obese type 2 diabetes with strongly insulin resistance and without dyslipidaemia. Animals were maintained during 2 months of dietary restriction (50 %) and were killed at 6 months of age. Some biochemical determinations were done using ELISA and Western blot. Data from the present study demonstrate that in Goto-Kakizaki rats the dietary restriction improved insulin resistance, NEFA levels and adipokine profile and ameliorated inflammatory cytokines in skeletal muscle. These results indicate that dietary restriction in type 2 diabetes enhances adipose tissue metabolism leading to an improved skeletal muscle insulin sensitivity.

  • Bitter melon (Momordica charantia L.) inhibits adipocyte hypertrophy and down regulates lipogenic gene expression in adipose tissue of diet-induced obese rats📎

    Abstract Title:

    Bitter melon (Momordica charantia L.) inhibits adipocyte hypertrophy and down regulates lipogenic gene expression in adipose tissue of diet-induced obese rats.

    Abstract Source:

    Br J Nutr. 2008 Feb;99(2):230-9. Epub 2007 Jul 26. PMID: 17651527

    Abstract Author(s):

    Hui-Ling Huang, Ya-Wen Hong, You-Hong Wong, Ying-Nien Chen, Jong-Ho Chyuan, Ching-Jang Huang, Pei-Min Chao

    Abstract:

    Bitter melon (Momordica charantia; BM) has been shown to ameliorate diet-induced obesity and insulin resistance. To examine the effect of BM supplementation on cell size and lipid metabolism in adipose tissues, three groups of rats were respectively fed a high-fat diet supplemented without (HF group) or with 5 % lyophilised BM powder (HFB group), or with 0.01 % thiazolidinedione (TZD) (HFT group). A group of rats fed a low-fat diet was also included as a normal control. Hyperinsulinaemia and glucose intolerance were observed in the HF group but not in HFT and HFB groups. Although the number of large adipocytes (>180 microm) of both the HFB and HFT groups was significantly lower than that of the HF group, the adipose tissue mass, TAG content and glycerol-3-phosphate dehydrogenase activity of the HFB group were significantly lower than those of the HFT group, implying that BM might reduce lipogenesis in adipose tissue. Experiment 2 was then conducted to examine the expression of lipogenic genes in adipose tissues of rats fed low-fat, HF or HFB diets. The HFB group showed significantly lower mRNA levels of fatty acid synthase, acetyl-CoA carboxylase-1, lipoprotein lipase and adipocyte fatty acid-binding protein than the HF group (P < 0.05). These results indicate BM can reduce insulin resistance as effective as the anti-diabetic drug TZD. Furthermore, BM can suppress the visceral fat accumulation and inhibit adipocyte hypertrophy, which may be associated with markedly down regulated expressions of lipogenic genes in the adipose.

  • Close adherence to a Mediterranean diet improves endothelial function in subjects with abdominal obesity📎

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    Abstract Title:

    Close adherence to a Mediterranean diet improves endothelial function in subjects with abdominal obesity.

    Abstract Source:

    Am J Clin Nutr. 2009 Aug;90(2):263-8. Epub 2009 Jun 10. PMID: 19515732

    Abstract Author(s):

    Loukianos S Rallidis, John Lekakis, Anastasia Kolomvotsou, Antonios Zampelas, Georgia Vamvakou, Stamatis Efstathiou, George Dimitriadis, Sotirios A Raptis, Dimitrios T Kremastinos

    Abstract:

    BACKGROUND: Abdominal obesity (AO) is associated with increased risk of cardiovascular disease and type 2 diabetes, whereas the Mediterranean diet exerts a cardioprotective effect.

    OBJECTIVE: We examined whether a close adherence to a Mediterranean-style diet improves endothelial function in individuals with AO.

    DESIGN: We recruited 90 subjects with AO without cardiovascular disease or type 2 diabetes. Participants were randomly assigned to the intervention or control group. Both groups were instructed to follow a Mediterranean-style diet for 2 mo. Subjects in the intervention group additionally had to follow a specific relevant daily and weekly food plan with close supervision by a dietitian and provision of basic foods. Flow-mediated dilatation (FMD), lipids, C-reactive protein (CRP), and insulin resistance with the homeostasis model assessment (HOMA-IR) were measured.

    RESULTS: After 2 mo, subjects in the intervention group increased their intake of total fat due to higher consumption of monounsaturated fatty acids as well as intakes of dietary fiber, vitamin C, and alcohol compared with the control group (all P<0.05). The intervention group also increased FMD ( 2.05%; 95% CI: 0.97, 3.13%), whereas no effect was found in the control group (-0.32%; 95% CI: -1.31, 0.67%). Changes in lipids and CRP concentrations did not differ between the 2 groups, whereas diastolic blood pressure decreased in the intervention group (-6.44 mm Hg; 95% CI: -8.57, -4.31 mm Hg) compared with the control group (-0.76 mm Hg; 95% CI: -2.83, 1.31 mm Hg). Finally, there was a trend for a reduction in HOMA-IR in the intervention group compared with the control group (P = 0.072).

    CONCLUSION: Close adherence to a Mediterranean-style diet achieved by close dietetic supervision improves endothelial function in subjects with AO.

  • Defect in insulin binding to receptors in obese man. Amelioration with calorie restriction📎

    Abstract Title:

    Defect in insulin binding to receptors in obese man. Amelioration with calorie restriction.

    Abstract Source:

    J Clin Invest. 1975 Jan;55(1):166-74. PMID: 1109176

    Abstract Author(s):

    J A Archer, P Gorden, J Roth

    Abstract:

    With insulin at 0.1 ng/ml, the binding of (125I)insulin in vitro to circulating lymphocytes from 11 obese patients was less than that observed with cells from 10 thin volunteers. Furthermore, with obese cells, unlabeled insulin was less effective in competing with labeled hormone for binding, both at low and high concentrations of unlabeled insulin. These differences were not accounted for by the high concentrations of insulin in the circulation of the obese patients at the time fthe blood was drawn, or by differences in degradation of hormone, or in the characteristics of the cell population. The decrease in binding appears to be due to a lowering of the receptor concentration, but some loss of affinity has not been excluded. Institution of a calorie restricted diet (nine patients) which ameliorated the hyperinsulinemia, produced an improvement in hormone binding. Since the insulin receptors of lymphocytes in metabolic disorders seem to reflect the state of insulin receptors or target cells such as liver and fat, the lymphocytes or other leukocytes appear to be ideal for studies of impaired cell responsiveness to hormones in man.

  • Differential effects of lipoic acid stereoisomers on glucose metabolism in insulin-resistant skeletal muscle.

    Abstract Title:

    Differential effects of lipoic acid stereoisomers on glucose metabolism in insulin-resistant skeletal muscle.

    Abstract Source:

    Am J Physiol. 1997 Jul;273(1 Pt 1):E185-91. PMID: 9252495

    Abstract Author(s):

    R S Streeper, E J Henriksen, S Jacob, J Y Hokama, D L Fogt, H J Tritschler

    Article Affiliation:

    Department of Physiology, University of Arizona, Tucson 85721-0093, USA.

    Abstract:

    The racemic mixture of the antioxidant alpha-lipoic acid (ALA) enhances insulin-stimulated glucose metabolism in insulin-resistant humans and animals. We determined the individual effects of the pure R-(+) and S-(-) enantiomers of ALA on glucose metabolism in skeletal muscle of an animal model of insulin resistance, hyperinsulinemia, and dyslipidemia: the obese Zucker (fa/fa) rat. Obese rats were treated intraperitoneally acutely (100 mg/kg body wt for 1 h) or chronically [10 days with 30 mg/kg of R-(+)-ALA or 50 mg/kg of S-(-)-ALA]. Glucose transport [2-deoxyglucose (2-DG) uptake], glycogen synthesis, and glucose oxidation were determined in the epitrochlearis muscles in the absence or presence of insulin (13.3 nM). Acutely, R-(+)-ALA increased insulin-mediated 2-DG-uptake by 64% (P<0.05), whereas S-(-)-ALA had no significant effect. Although chronic R-(+)-ALA treatment significantly reduced plasma insulin (17%) and free fatty acids (FFA; 35%) relative to vehicle-treated obese animals, S-(-)-ALA treatment further increased insulin (15%) and had no effect on FFA. Insulin-stimulated 2-DG uptake was increased by 65% by chronic R-(+)-ALA treatment, whereas S-(-)-ALA administration resulted in only a 29% improvement. Chronic R-(+)-ALA treatment elicited a 26% increase in insulin-stimulated glycogen synthesis and a 33% enhancement of insulin-stimulated glucose oxidation. No significant increase in these parameters was observed after S-(-)-ALA treatment. Glucose transporter (GLUT-4) protein was unchanged after chronic R-(+)-ALA treatment but was reduced to 81 +/- 6% of obese control with S-(-)-ALA treatment. Therefore, chronic parenteral treatment with the antioxidant ALA enhances insulin-stimulated glucose transport and non-oxidative and oxidative glucose metabolism in insulin-resistant rat skeletal muscle, with the R-(+) enantiomer being much more effective than the S-(-) enantiomer.

  • Effect of a high monounsaturated fatty acids diet and a Mediterranean diet on serum lipids and insulin sensitivity in adults with mild abdominal obesity.

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    Abstract Title:

    Effect of a high monounsaturated fatty acids diet and a Mediterranean diet on serum lipids and insulin sensitivity in adults with mild abdominal obesity.

    Abstract Source:

    Nutr Metab Cardiovasc Dis. 2009 Aug 17. Epub 2009 Aug 17. PMID: 19692213

    Abstract Author(s):

    M B Bos, J H M de Vries, E J M Feskens, S J van Dijk, D W M Hoelen, E Siebelink, R Heijligenberg, L C P G M de Groot

    Abstract:

    BACKGROUND AND AIMS: Diets high in monounsaturated fatty acids (MUFA) such as a Mediterranean diet may reduce the risk of cardiovascular diseases by improving insulin sensitivity and serum lipids. Besides being high in MUFA, a Mediterranean diet also contains abundant plant foods, moderate wine and low amounts of meat and dairy products, which may also play a role. We compared the effects of a high MUFA-diet with a diet high in saturated fatty acids (SFA) and the additional effect of a Mediterranean diet on insulin sensitivity and serum lipids.

    METHODS AND RESULTS: A randomized parallel controlled-feeding trial was performed, in 60 non-diabetics (40-65y) with mild abdominal obesity. After a two week run-in diet high in SFA (19 energy-%), subjects were allocated to a high MUFA-diet (20 energy-%), a Mediterranean diet (MUFA 21 energy-%), or the high SFA-diet, for eight weeks. The high MUFA and the Mediterranean diet did not affect fasting insulin concentrations. The high MUFA-diet reduced total cholesterol (-0.41mmol/L, 95% CI -0.74, -0.09) and LDL-cholesterol (-0.38mmol/L, 95% CI -0.65, -0.11) compared with the high SFA-diet, but not triglyceride concentrations. The Mediterranean diet increased HDL-cholesterol concentrations (+0.09mmol/L, 95% CI 0.0, 0.18) and reduced the ratio of total cholesterol/HDL-cholesterol (-0.39, 95% CI -0.62, -0.16) compared with the high MUFA-diet.

    CONCLUSION: Replacing a high SFA-diet with a high MUFA or a Mediterranean diet did not affect insulin sensitivity, but improved serum lipids. The Mediterranean diet was most effective, it reduced total and LDL-cholesterol, and also increased HDL-cholesterol and reduced total cholesterol/HDL-cholesterol ratio.

  • Effect of puerarin on type II diabetes mellitus with orthopaedic footwear.

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    Abstract Title:

    Effect of puerarin on type II diabetes mellitus with orthopaedic footwear.

    Abstract Source:

    Pak J Pharm Sci. 2017 Sep ;30(5(Special)):1899-1903. PMID: 29084664

    Abstract Author(s):

    Qinyuan Yu, Wenzhong Han, Yixi Zhu, Hua Zhai

    Article Affiliation:

    Qinyuan Yu

    Abstract:

    In recent years, the antioxidant efficacy of puerarin has been recognized. However, there is less research on Puerarin used in diabetes. This paper analyzes the effect of puerarin on type II diabetes mellitus induced by streptozotocin combined with orthopaedic footwear. In this study, 80 Sprague Dawley (SD) rats were fed with high fat and high sucrose diet for one month, and 1% streptozotocin (STZ) was used to induce type II diabetes mellitus. After 6 weeks aerobic exercise and puerarin intervention in rats, the effect of aerobic exercise and puerarin intervention on antioxidant ability in diabetic rats was investigated. The results showed that aerobic exercise and puerarin intervention can improve the insulin resistance in rats. Meanwhile, the annual incidence of foot ulcers in diabetic patients is 2%, while orthopaedic footwear can reduce the probability of diabetic foot ulcers. In general, exercise and puerarin intervention can really play a role in the prevention and treatment of diabetes, such as improving the metabolic status of diabetic patients and reducing their dependence on drugs.

  • Effects of crocin and voluntary exercise, alone or combined, on heart VEGF-A and HOMA-IR of HFD/STZ induced type 2 diabetic rats.

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    Abstract Title:

    Effects of crocin and voluntary exercise, alone or combined, on heart VEGF-A and HOMA-IR of HFD/STZ induced type 2 diabetic rats.

    Abstract Source:

    J Endocrinol Invest. 2016 Apr 19. Epub 2016 Apr 19. PMID: 27094045

    Abstract Author(s):

    V Ghorbanzadeh, M Mohammadi, H Dariushnejad, L Chodari, G Mohaddes

    Article Affiliation:

    V Ghorbanzadeh

    Abstract:

    BACKGROUND:Hyperglycemia is the main risk factor for microvascular complications in type 2 diabetes. Crocin and voluntary exercise have anti-hyperglycemic effects in diabetes. In this research, we evaluated the effects of crocin and voluntary exercise alone or combined on glycemia control and heart level of VEGF-A.

    MATERIALS AND METHODS:Animals were divided into eight groups as: control (con), diabetes (Dia), crocin (Cro), voluntary exercise (Exe), crocin and voluntary exercise (Cro-Exe), diabetic-crocin (Dia-Cro), diabetic-voluntary exercise (Dia-Exe), diabetic-crocin-voluntary exercise (Dia-Cro-Exe). Type 2 diabetes was induced by a high-fat diet (4 weeks) and injection of streptozotocin (STZ) (i.p, 35 mg/kg). Animals received oral administration of crocin (50 mg/kg) or performed voluntary exercise alone or together for 8 weeks. Oral glucose tolerance test (OGTT) was performed on overnight fasted control, diabetic and treated rats after 8 weeks of treatment. Then, serum insulin and heart VEGF-A protein levels were measured.

    RESULTS:Crocin combined with voluntary exercise significantly decreased blood glucose levels (p < 0.001) and insulin resistance (HOMA-IR) (p < 0.001) compared to diabetic group. VEGF-A level was significantly (p < 0.01) lower in Dia group compared to control group. The combination of crocin and voluntary exercise significantly enhanced VEGF-A protein levels in Dia-Cro-Exe and Cro-Exe group compared to diabetic and control groups, respectively; p < 0.001 and p < 0.05.

    DISCUSSION:Crocin combined with voluntary exercise improved insulin resistance (HOMA-IR) and reduced glucose levels in diabetic rats. Since both crocin and voluntary exercise can increase VEGF-A protein expression in heart tissue, they probably are able to increase angiogenesis in diabetic animals.

  • Effects of daily mechanical horseback riding on insulin sensitivity and resting metabolism in middle-aged type 2 diabetes mellitus patients.

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    Abstract Title:

    Effects of daily mechanical horseback riding on insulin sensitivity and resting metabolism in middle-aged type 2 diabetes mellitus patients.

    Abstract Source:

    Nagoya J Med Sci. 2010 Aug;72(3-4):129-37. PMID: 20942267

    Abstract Author(s):

    Yoshiyuki Hosaka, Masaru Nagasaki, Gustavo Bajotto, Youichi Shinomiya, Takahisa Ozawa, Yuzo Sato

    Article Affiliation:

    Hosaka Medical Clinic, Fujiyoshida, Japan.

    Abstract:

    The present study was conducted to investigate the effect of daily passive exercise using a horseback riding machine (Joba) on insulin sensitivity and resting metabolism in middle-aged, diabetic patients. Participants were 24 type 2 diabetes mellitus patients aged 59 +/- 8 years (mean +/- SD; range from 43 to 75 years of age). Patients were randomly divided into control (normal lifestyle) and Joba exercise groups. The latter group was instructed to perform one 30-min session of Joba riding per day, 7 times per week, for 3 months. Compared with baseline values, serum immunoreactive insulin (IRI) concentrations decreased and HOMA-IR was improved by Joba training. In addition, exercise duration per day significantly correlated (r = -0.65) with changes in serum IRI, and 3-month mechanical horseback riding significantly increased the resting metabolic rate of the patients. These results suggest that daily Joba passive exercise is potentially useful as a means to improve insulin sensitivity and resting metabolism in diabetic patients. The Joba fitness equipment can prove especially useful as an alternative exercise therapy for aged individuals incapable of performing independent exercise or for those who suffer from knee-joint disorders.

  • Effects of Exercise Modality on Insulin Resistance and Ectopic Fat in Adolescents with Overweight and Obesity: A Randomized Clinical Trial.

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    Abstract Title:

    Effects of Exercise Modality on Insulin Resistance and Ectopic Fat in Adolescents with Overweight and Obesity: A Randomized Clinical Trial.

    Abstract Source:

    J Pediatr. 2018 Dec 12. Epub 2018 Dec 12. PMID: 30554789

    Abstract Author(s):

    SoJung Lee, Ingrid Libman, Kara Hughan, Jennifer L Kuk, Jong H Jeong, Di Zhang, Silva Arslanian

    Article Affiliation:

    SoJung Lee

    Abstract:

    OBJECTIVE:To examine whether a combined aerobic exercise and resistance exercise is more effective than either aerobic exercise or resistance exercise alone in improving insulin sensitivity and reducing total adiposity and ectopic fat in adolescents.

    STUDY DESIGN:A total of 118 sedentary adolescents with overweight/obesity (body mass index>85th percentile, 12-17 years) were recruited from October 2013 through April 2017 at Children's Hospital of Pittsburgh. Participants were randomized to 1 of the following 6-month exercise groups (3 d/wk, 180 min/wk): aerobic exercise (n = 38), resistance exercise (n = 40), and combined aerobic exercise and resistance exercise (n = 40). The primary outcome was the change in insulin-stimulated glucose disposal by a 3-hour hyperinsulinemic-euglycemic clamp. The secondary outcomes were changes in liver fat by proton magnetic resonance spectroscopy and intermuscular adipose tissue by computed tomography.

    RESULTS:Of the 118 participants randomized, 85 participants (72%) completed the study with 90% exercise attendance. Total adiposity reduced similarly in all groups (-2%, P < .05). After adjusting for age and sex, insulin-stimulated glucose disposal increased (P < .05) in all groups, with the increase in the aerobic exercise group being greater than the resistance exercise group (1.7 ± 0.1 vs 0.7 ± 0.1 mg/kg/min, P < .05) but not different from the combined group (1.2 ± 0.1 mg/kg/min). Liver fat was reduced (P < .05) in the aerobic exercise (-0.6%) and combined (-0.6%) groups but not in the resistance exercise group (-0.3%, P > .05). Intermuscular adipose tissue decreased (P < .05) similarly in all groups.

    CONCLUSION:Combined aerobic exercise and resistance exercise and aerobic exercise alone are similarly beneficial in improving insulin sensitivity and reducing ectopic fat in adolescents with obesity.

    TRIAL REGISTRATION:ClinicalTrials.govNCT01938950.

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