Transient increase in HDL-cholesterol during weight gain by hyperalimentation in healthy subjects

The effect of results-based motivating system on metabolic risk factors of non-communicable diseases: A field trial study

BACKGROUND

Non-communicable diseases can be controlled and managed by reducing their associated metabolic risk factors. In this study, a set of intervention packages were designed to reduce the prevalence of three common metabolic risk factors (hypertension, hyperlipidemia, and obesity and overweight) in the community by motivating non-physician health workers.

METHODS

A field trial study was conducted in 4 districts of Iran. Thirty-two community health centers were randomly selected. A survey of 30 to 70-year-old was conducted to measure baseline metabolic risk factors. The intervention packages focused on improving hypertension, hyperlipidemia, obesity and overweight. The interventions included goal-setting, evidence-based education, operational planning, and incentive payments for non-physician health workers. A second survey to measure the final metabolic risk factors was performed after one year. The difference-in-difference method was used to evaluate the effectiveness of the intervention packages.

RESULTS

The average age of participants in both surveys was 49 years. The interventions had statistically significant effects only on decreasing the prevalence of overweight and obesity. The package with all the interventions except pay-for-performance decreased the odds of overweight and obesity to 0.57 (95% CI: 0.34, 0.95).

CONCLUSIONS

Involving non-physician health workers and having action plans based on the health needs of the covered population can decrease obesity and overweight in the community. However, longer trials are needed to observe the effects on hypertension and hyperlipidemia.

A multi-scale digital twin for adiposity-driven insulin resistance in humans: diet and drug effects

BACKGROUND

The increased prevalence of insulin resistance is one of the major health risks in society today. Insulin resistance involves both short-term dynamics, such as altered meal responses, and long-term dynamics, such as the development of type 2 diabetes. Insulin resistance also occurs on different physiological levels, ranging from disease phenotypes to organ-organ communication and intracellular signaling. To better understand the progression of insulin resistance, an analysis method is needed that can combine different timescales and physiological levels. One such method is digital twins, consisting of combined mechanistic mathematical models. We have previously developed a model for short-term glucose homeostasis and intracellular insulin signaling, and there exist long-term weight regulation models. Herein, we combine these models into a first interconnected digital twin for the progression of insulin resistance in humans.

METHODS

The model is based on ordinary differential equations representing biochemical and physiological processes, in which unknown parameters were fitted to data using a MATLAB toolbox.

RESULTS

The interconnected twin correctly predicts independent data from a weight increase study, both for weight-changes, fasting plasma insulin and glucose levels, and intracellular insulin signaling. Similarly, the model can predict independent weight-change data in a weight loss study with the weight loss drug topiramate. The model can also predict non-measured variables.

CONCLUSIONS

The model presented herein constitutes the basis for a new digital twin technology, which in the future could be used to aid medical pedagogy and increase motivation and compliance and thus aid in the prevention and treatment of insulin resistance.

Hyperandrogenemia Induced by Letrozole Treatment of Pubertal Female Mice Results in Hyperinsulinemia Prior to Weight Gain and Insulin Resistance

Women with polycystic ovary syndrome (PCOS) diagnosed with hyperandrogenism and ovulatory dysfunction have an increased risk of developing metabolic disorders, including type 2 diabetes and cardiovascular disease. We previously developed a model that uses letrozole to elevate endogenous testosterone levels in female mice. This model has hallmarks of PCOS, including hyperandrogenism, anovulation, and polycystic ovaries, as well as increased abdominal adiposity and glucose intolerance. In the current study, we further characterized the metabolic dysfunction that occurs after letrozole treatment to determine whether this model represents a PCOS-like metabolic phenotype. We focused on whether letrozole treatment results in altered pancreatic or liver function as well as insulin resistance. We also investigated whether hyperinsulinemia occurs secondary to weight gain and insulin resistance in this model or if it can occur independently. Our study demonstrated that letrozole-treated mice developed hyperinsulinemia after 1 week of treatment and without evidence of insulin resistance. After 2 weeks of letrozole treatment, mice became significantly heavier than placebo mice, demonstrating that weight gain was not required to develop hyperinsulinemia. After 5 weeks of letrozole treatment, mice exhibited blunted glucose-stimulated insulin secretion, insulin resistance, and impaired insulin-induced phosphorylation of AKT in skeletal muscle. Moreover, letrozole-treated mice exhibited dyslipidemia after 5 weeks of treatment but no evidence of hepatic disease. Our study demonstrated that the letrozole-induced PCOS mouse model exhibits multiple features of the metabolic dysregulation observed in obese, hyperandrogenic women with PCOS. This model will be useful for mechanistic studies investigating how hyperandrogenemia affects metabolism in females.

Variations of body composition, physical activity and caloric intake in schoolchildren during national holidays

Scientific literature has described that a significant body weight increase in schoolchildren occurs during some holiday periods (summer, winter, and thanksgiving holidays), harming their health. In this regard, it is thought that this phenomenon is mainly due to changes in eating habits and the variation in levels of physical activity; however, this approach has not yet been explored during national holidays (NAH) in Chile.

PURPOSE

To determine any changes in body composition, physical activity and caloric intake during NAH.

METHODS

A total of 46 schoolchildren (24 boys, age 10.5 ± 0.5; BMI 21.7 ± 4.7) participated. Measurements were performed 2 days before and after the NAH (9 days). Weight was measured and fat percentage was established using the Slaughter formula. Levels of physical activity were measured with accelerometers, validating 3 weekdays and 1 weekend; caloric intake was established through a 24-h recall.

RESULTS

Weight, percentage of fat and caloric intake increased significantly (250 g, 2.2 % and 733.3 kcal, respectively; p < 0.05); however, none of the variables of physical activity showed significant changes.

CONCLUSION

The change in caloric intake seems to be the main cause of weight and fat gain during the NAH.

Role of dietary fats in modulating cardiometabolic risk during moderate weight gain: a randomized double-blind overfeeding trial (LIPOGAIN study)

BACKGROUND

Whether the type of dietary fat could alter cardiometabolic responses to a hypercaloric diet is unknown. In addition, subclinical cardiometabolic consequences of moderate weight gain require further study.

METHODS AND RESULTS

In a 7-week, double-blind, parallel-group, randomized controlled trial, 39 healthy, lean individuals (mean age of 27±4) consumed muffins (51% of energy [%E] from fat and 44%E refined carbohydrates) providing 750 kcal/day added to their habitual diets. All muffins had identical contents, except for type of fat; sunflower oil rich in polyunsaturated fatty acids (PUFA diet) or palm oil rich in saturated fatty acids (SFA diet). Despite comparable weight gain in the 2 groups, total: high-density lipoprotein (HDL) cholesterol, low-density lipoprotein:HDL cholesterol, and apolipoprotein B:AI ratios decreased during the PUFA versus the SFA diet (-0.37±0.59 versus +0.07±0.29, -0.31±0.49 versus +0.05±0.28, and -0.07±0.11 versus +0.01±0.07, P=0.003, P=0.007, and P=0.01 for between-group differences), whereas no significant differences were observed for other cardiometabolic risk markers. In the whole group (ie, independently of fat type), body weight increased (+2.2%, P<0.001) together with increased plasma proinsulin (+21%, P=0.007), insulin (+17%, P=0.003), proprotein convertase subtilisin/kexin type 9, (+9%, P=0.008) fibroblast growth factor-21 (+31%, P=0.04), endothelial markers vascular cell adhesion molecule-1, intercellular adhesion molecule-1, and E-selectin (+9, +5, and +10%, respectively, P<0.01 for all), whereas nonesterified fatty acids decreased (-28%, P=0.001).

CONCLUSIONS

Excess energy from PUFA versus SFA reduces atherogenic lipoproteins. Modest weight gain in young individuals induces hyperproinsulinemia and increases biomarkers of endothelial dysfunction, effects that may be partly outweighed by the lipid-lowering effects of PUFA.

CLINICAL TRIAL REGISTRATION URL

http://ClinicalTrials.gov. Unique identifier: NCT01427140.

Treatment of lipid disorders in obesity

Obesity is the most common cause of secondary hyperlipidemia. Atherogenic dyslipidemia refers to elevated triglycerides, low HDL-cholesterol and small dense LDL associated with visceral obesity and metabolic syndrome. Obesity may also be associated with isolated low HDL-cholesterol or high triglycerides and postprandial hyperlipidemia. While some obese patients have high LDL cholesterol concentrations, obesity has a more pronounced effect on other atherogenic lipids and lipoproteins. Obesity may aggravate familial lipid disorders. Lipid disorders in obesity are responsive to weight loss, pharmacotherapy and weight loss surgery. Statins are the lipid-lowering drug of choice, together with lifestyle change. Hard clinical end point data to support combinations of statins with other drugs is lacking. After weight loss surgery, the absolute risk of cardiovascular disease should be reassessed, but tools to facilitate risk assessment need to be developed.