Resistance training improves skeletal muscle insulin sensitivity in elderly offspring of overweight and obese mothers

Unique advantages of dynamic l-[11C]methionine PET/CT for assessing the rate of skeletal muscle protein synthesis: A pilot trial in young men

Although the standard method to evaluate skeletal muscle protein synthesis (MPS) is muscle biopsy, the method is invasive and problematic for multisite use. We conducted a small pilot study in volunteers to investigate changes in MPS according to skeletal muscle site using a noninvasive method in which 6 healthy young men were given yogurt (containing 20 g milk protein) or water, and 1 h later, l-[11C]methionine ([11C]Met) was administered intravenously. Dynamic PET/CT imaging of their thighs was performed for 60 min. The influx constant Ki of [11C]Met in skeletal muscle protein was calculated as an index of MPS using a Patlak plot, and found to be 0.6%-28% higher after ingesting yogurt than after water in 5 of the 6 volunteer participants, but it was 34% lower in the remaining participant. Overall, this indicated no significant increase in Ki after ingesting milk protein. However, when the quadriceps and hamstring muscles were analyzed separately, we found a significant difference in Ki. This demonstrates the potential of visualizing MPS by calculating the Ki for each voxel and reconstructing it as an image, which presents unique advantages of [11C]Met PET/CT for evaluating MPS, such as site-specificity and visualization.

Comparative effectiveness of different modes of exercise interventions in diabetics with frailty in China: a systematic review and a network meta-analysis

OBJECTIVE

To systematically evaluate the efficacy of different training modes in patients with diabetes decline.

METHODS

PubMed, Cochrane Library, EMbase, Web of Science, CNKI, VIP, WANFANG, SinoMed were searched in computer to collect randomized controlled trials (RCTs) of training intervention in patients with diabetes and frailty, and the search time was as of May 21, 2023. After two review authors independently screened studies, extracted data, and assessed the risk of bias of included studies, network meta-analysis was performed using Stata14.0 and R4.3.1 software. Fasting blood glucose (FGB), glycosylated haemoglobin (HbA1c), two-hour postprandial blood glucose (PBG), total cholesterol (TCH), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), Short Physical Performance Battery (SPPB), and body mass index (BMI) were used as outcome measures.

RESULTS

A total of 15 RCTs were included, including 1550 patients. The results of the network meta-analysis showed that integrated training reduced FBG compared with the control group; integrated training, Pilates training, resistance training can reduce HbA1c; Pilates training and resistance training can reduce PBG; integrated training, Pilates training, resistance training can reduce TCH; Pilates training and resistance training can reduce TG; resistance training improves BMI. The results of the best probability ranking showed that multi-group training had the most significant effect on improving PBG and SPPB scores.

CONCLUSION

The current evidence suggests that multi-group training is the best way to reduce fasting blood glucose and improve physical activity before meals, and Pilates training may be the best way to reduce glycated hemoglobin, blood glucose two hours after meals, improve blood lipid level and BMI in patients with diabetes in China.

TRIAL REGISTRATION

PROSPERO registration number for this study: CRD42023427868.

The Effects of Resistance Exercise Training on Skeletal Muscle Metabolism and Insulin Resistance Development in Female Rodents with Type 1 Diabetes

The etiology of insulin resistance (IR) development in type 1 diabetes mellitus (T1DM) remains unclear; however, impaired skeletal muscle metabolism may play a role. While IR development has been established in male T1DM rodents, female rodents have yet to be examined in this context. Resistance exercise training (RT) has been shown to improve IR and is associated with a lower risk of hypoglycemia onset in T1DM compared to aerobic exercise. The purpose of this study was to investigate the effects of RT on IR development in female T1DM rodents. Forty Sprague Dawley eight-week-old female rats were divided into four groups: control sedentary (CS; n = 10), control trained (CT; n = 10), T1DM sedentary (DS; n = 10), and T1DM trained (DT; n = 10). Multiple low-dose streptozotocin injections were used to induce T1DM. Blood glucose levels were maintained in the 4-9 mmol/l range with intensive insulin therapy. CT and DT underwent weighted ladder climbing 5 days/week for six weeks. Intravenous glucose tolerance tests (IVGTT) were conducted on all animals following the six-week period. Results demonstrate that DS animals exhibited significantly increased weekly blood glucose measures compared to all groups including DT (p < 0.0001), despite similar insulin dosage levels. This was concomitant with a significant increase in insulin-adjusted area under the curve following IVGTT in DS (p < 0.05), indicative of a reduction in insulin sensitivity. Both DT and DS exhibited greater serum insulin concentrations compared to CT and CS (p < 0.05). DS animals also exhibited significantly greater glycogen content in white gastrocnemius muscle compared to CS and DT (p < 0.05), whereas DT and DS animals exhibited greater p-Akt: Akt ratio in the white vastus lateralis muscle and citrate synthase activity in the red vastus lateralis muscle compared to CS and CT (p < 0.05). These results indicate that female rodents with T1DM develop poor glycemic control and IR which can be attenuated with RT, possibly related to differences in intramyocellular glycogen content.

A sex-specific association of leukocyte telomere length with thigh muscle mass

OBJECTIVES

Telomeres are DNA-protein complexes at the ends of linear chromosomes that protect against DNA degradation. Telomeres shorten during normal cell divisions and therefore, telomere length is an indicator of mitotic-cell age. In humans, telomere shortening is a potential biomarker for disease risk, progression and premature death. Physical activity has been associated with longer leukocyte telomere length (LTL) in some studies. In the current study the relationship between LTL, thigh muscle mass and adipose tissue distribution was explored.

METHODS

We performed anthropometric measurements and magnetic resonance imaging (MRI) measurements of the thigh in 149 healthy subjects (77 male, 72 female). LTL was measured using qPCR. Additionally, the subjects answered a questionnaire concerning their training behaviour.

RESULTS

In male subjects, LTL was significantly associated with thigh muscle mass, independent of age and body mass index (p=0.006). In addition, a slight association of LTL with weekly endurance units in the male group was found. These relations could not be observed in females.

CONCLUSIONS

In conclusion, we observed a sex-specific association of LTL and thigh muscle mass in healthy males. The reason of this sex-specific association is currently unclear, but could be related to different training effects and/or hormonal pathways in men and women.

Telomere length as a marker of changes in body composition and fractures-an analysis of data from the NHANES 2001-2002

Purpose

There has been an association between changes in body composition, fracture incidence, and age in previous studies. Telomere length (TL) has been proposed as a biomarker of aging. However, the relationship between body composition, fractures, and TL has rarely been studied. Therefore, this study aimed to investigate the correlation between TL and body composition and fractures.Patients and methods: 20950 participants from the 2001-2002 National Health and Nutrition Examination Survey (NHANES) were included in the final analysis. In NHANES, body compositions were measured with DXA, and TL was determined with quantitative PCR. Correlation analysis of TL and body composition was conducted using multivariate weighted linear regression and logistic regression models.

Results

The results showed that TL positively correlated with bone mineral density (BMD) and bone mineral content (BMC) in most body parts. However, BMD and BMC were negatively connected with TL in the upper limbs and skull. Fat content was negatively associated with TL, while muscle content was positively linked to TL. In addition, TL's trend analysis results were consistent with the regression model when transformed from a continuous to a classified variable. An increase in TL was associated with a higher incidence of wrist fractures, while a decrease in spine fractures. The above correlation also has a certain degree of sex specificity.

Conclusion

Our study indicate that TL is associated with body composition as well as fractures, but further research is needed to confirm these contrasting associations in the skull, upper limbs, and wrists.

Effects of free weight and body mass-based resistance training on thigh muscle size, strength and intramuscular fat in healthy young and middle-aged individuals

NEW FINDINGS

What is the central question of this study? How do free weight resistance training (RT) and body mass-based RT for 8 weeks compare for isometric muscular strength, muscle size and intramuscular fat (IMF) content in the quadriceps femoris? What is the main finding and its importance? Free weight and body mass-based RTs could induce muscle hypertrophy; however, decreased IMF content was observed following the body mass-based RT alone.

ABSTRACT

The objective of this study was to investigate the effects of free weight and body mass-based resistance training (RT) on muscle size and thigh intramuscular fat (IMF) in young and middle-aged individuals. Healthy individuals (aged 30-64 years) were assigned to either a free weight RT group (n = 21) or a body mass-based RT group (n = 16). Both groups performed whole-body resistance exercise twice a week for 8 weeks. Free weight resistance exercises (squats, bench press, deadlift, dumbbell rows and back range) involved 70% one repetition maximum, with three sets of 8-12 repetitions per exercise. The nine body mass-based resistance exercises (leg raise, squats, rear raise, overhead shoulder mobility exercise, rowing, dips, lunge, single-leg Romanian deadlifts and push-ups) included the maximum possible repetitions per session, which were performed in one or two sets. Mid-thigh magnetic resonance images using the two-point Dixon method were taken pre- and post-training. The muscle cross-sectional area (CSA) and IMF content in the quadriceps femoris were measured from the images. Both the groups showed significantly increased muscle CSA post-training (free weight RT group, P = 0.001; body mass-based RT group, P = 0.002). IMF content in the body mass-based RT group significantly decreased (P = 0.036) but did not significantly change in the free weight RT group (P = 0.076). These results suggest that the free weight and body mass-based RTs could induce muscle hypertrophy; however, in healthy young and middle-aged individuals, decreased IMF content was induced following the body mass-based RT alone.

Resistance Training Increases White Matter Density in Frail Elderly Women

We aimed to investigate the effects of maternal obesity on brain structure and metabolism in frail women, and their reversibility in response to exercise. We recruited 37 frail elderly women (20 offspring of lean/normal-weight mothers (OLM) and 17 offspring of obese/overweight mothers (OOM)) and nine non-frail controls to undergo magnetic resonance and diffusion tensor imaging (DTI), positron emission tomography with Fluorine-18-fluorodeoxyglucose (PET), and cognitive function tests (CERAD). Frail women were studied before and after a 4-month resistance training, and controls were studied once. White matter (WM) density (voxel-based morphometry) was higher in OLM than in OOM subjects. Exercise increased WM density in both OLM and OOM in the cerebellum in superior parietal regions in OLM and in cuneal and precuneal regions in OOM. OLM gained more WM density than OOM in response to intervention. No significant results were found from the Freesurfer analysis, nor from PET or DTI images. Exercise has an impact on brain morphology and cognition in elderly frail women.

p62/Sqstm1 rescue in muscle retards the progression of steatohepatitis in p62/Sqstm1-null mice fed a high-fat diet

Introduction: Obesity is a risk factor for many diseases because it leads to a reduction in skeletal muscle mass and promotes insulin resistance. p62/Sqstm1-knockout mice are a model of metabolic syndrome; show obesity, insulin resistance, and non-alcoholic fatty liver (NAFL); and develop non-alcoholic steatohepatitis (NASH) in response to the feeding of a high-fat diet (HFD). These phenotypes suggest that muscle p62 may prevent obesity-induced muscle dysfunction. In the present study, we aimed to determine the effects of muscle p62 on skeletal muscle mass, muscle strength, insulin resistance, and NASH pathology.

Methods: We generated muscle-specific p62 gene rescue mice (p62-mRes), which express p62 only in muscle and were derived from p62-knock out mice (p62^KIKI) using the cre/loxp system. p62^KIKI and p62-mRes mice were fed an HFD for 20 weeks and their phenotypes were compared.

Results: HFD-feeding caused severe obesity in both p62^KIKI and p62-mRes mice, but there was no effect of muscle p62 on body mass. Limb skeletal muscle mass, grip strength, and the cross-sectional area of muscle fibers were higher in p62-mRes mice than in p62^KIKI. The glucose tolerance and insulin sensitivity of the p62-mRes mice were also superior. The protein expression of mechanistic target of rapamycin, which promotes muscle protein synthesis, and GLUT4, a glucose transporter in skeletal muscle, were higher in the p62-mRes mice. p62^KIKI mice developed severe NASH when fed an HFD, but the progression of NASH was retarded by p62 gene rescue in muscle, and the expression of Tgf-β1, which encodes a factor that promotes hepatic fibrosis, was reduced.

Conclusion: Rescue of muscle-specific p62 in the whole-body p62 knock-out mice ameliorates the insulin resistance and retards the progression of NASH caused by systemic p62 ablation.

Early life programming of health and disease: the long-term consequences of obesity in pregnancy: a narrative review

The prevalence of overweight and obesity is rising in all parts of the world and among young women it presents a very clear danger during pregnancy. Women who are overweight or who gain excessive weight during pregnancy are at greater risk of complications in pregnancy and labour, and are more likely to lose their child to stillbirth, or themselves die during pregnancy. This narrative review considers the evidence that in addition to increasing risk of poor pregnancy outcomes, obesity has the capacity to programme fetuses to be at greater risk of cardiometabolic disorders later in life. An extensive body of evidence from prospective and retrospective cohorts, and record linkage studies demonstrates associations of maternal obesity and/or gestational diabetes with cardiovascular disease, type-1 and type-2 diabetes. Studies in animals suggest that these associations are underpinned by adaptations that occur in fetal life, which remodel the structures of major organs including the brain, kidney and pancreas. This article is protected by copyright. All rights reserved.

Maternal overnutrition elevates offspring's blood pressure-A systematic review and meta-analysis

BACKGROUND

Maternal overnutrition during pregnancy predisposes the offspring to cardiometabolic diseases.

OBJECTIVES

This systematic review and meta-analysis aimed to investigate the association between maternal overnutrition and offspring's blood pressure (BP) and the effect of offspring's obesity on this association.

DATA SOURCES

PubMed, EMBASE, Clinicaltrials.gov, CENTRAL.

STUDY SELECTION AND DATA EXTRACTION

Human studies published in English before October 2021 were identified that presented quantitative estimates of association between maternal overnutrition just before or during pregnancy and the offspring's BP.

SYNTHESIS

Random-effect model with the DerSimonian and Laird weighting method was used to analyse regression coefficients or mean differences.

RESULTS

After selection, 17 observational studies (140,517 mother-offspring pairs) were included. Prepregnancy body mass index (ppBMI) showed positive correlation with BP in offspring (regression coefficient for systolic: 0.38 mmHg per kg/m² , 95% confidence interval (CI) 0.17, 0.58; diastolic: 0.10 mmHg per kg/m² , 95% CI 0.05, 0.14). These indicate 1.9 mmHg increase in systolic and 0.5 mmHg increase in diastolic BP of offspring with every 5 kg/m² gain in maternal ppBMI. Results on coefficients adjusted for offspring's BMI also showed association (systolic: 0.08 mmHg per kg/m² , 95% CI 0.04, 0.11; diastolic: 0.03 mmHg per kg/m² , 95% CI 0.01, 0.04). Independent from ppBMI, gestational weight gain (GWG) showed positive correlation with systolic BP (systolic BP: 0.05 mmHg per kg, 95% CI 0.01, 0.09), but not after adjustment for offspring's BMI. Mean systolic BP was higher in children of mothers with excessive GWG than in those of mothers with optimal GWG (difference: 0.65 mmHg, 95% CI 0.25, 1.05).

CONCLUSIONS

Independent from offspring's BMI, higher prepregnancy BMI may increase the risk for hypertension in offspring. The positive association between GWG and offspring's systolic BP is indirect via offspring's obesity. Reduction in maternal obesity and treatment of obesity in children of obese mothers are needed to prevent hypertension.

Exercising for Insulin Sensitivity - Is There a Mechanistic Relationship With Quantitative Changes in Skeletal Muscle Mass?

Skeletal muscle (SM) tissue has been repetitively shown to play a major role in whole-body glucose homeostasis and overall metabolic health. Hence, SM hypertrophy through resistance training (RT) has been suggested to be favorable to glucose homeostasis in different populations, from young healthy to type 2 diabetic (T2D) individuals. While RT has been shown to contribute to improved metabolic health, including insulin sensitivity surrogates, in multiple studies, a universal understanding of a mechanistic explanation is currently lacking. Furthermore, exercised-improved glucose homeostasis and quantitative changes of SM mass have been hypothesized to be concurrent but not necessarily causally associated. With a straightforward focus on exercise interventions, this narrative review aims to highlight the current level of evidence of the impact of SM hypertrophy on glucose homeostasis, as well various mechanisms that are likely to explain those effects. These mechanistic insights could provide a strengthened rationale for future research assessing alternative RT strategies to the current classical modalities, such as low-load, high repetition RT or high-volume circuit-style RT, in metabolically impaired populations.

Curcuma Longa, the "Golden Spice" to Counteract Neuroinflammaging and Cognitive Decline-What Have We Learned and What Needs to Be Done

Due to the global increase in lifespan, the proportion of people showing cognitive impairment is expected to grow exponentially. As target-specific drugs capable of tackling dementia are lagging behind, the focus of preclinical and clinical research has recently shifted towards natural products. Curcumin, one of the best investigated botanical constituents in the biomedical literature, has been receiving increased interest due to its unique molecular structure, which targets inflammatory and antioxidant pathways. These pathways have been shown to be critical for neurodegenerative disorders such as Alzheimer’s disease and more in general for cognitive decline. Despite the substantial preclinical literature on the potential biomedical effects of curcumin, its relatively low bioavailability, poor water solubility and rapid metabolism/excretion have hampered clinical trials, resulting in mixed and inconclusive findings. In this review, we highlight current knowledge on the potential effects of this natural compound on cognition. Furthermore, we focus on new strategies to overcome current limitations in its use and improve its efficacy, with attention also on gender-driven differences.

Muscle Lipid Droplets: Cellular Signaling to Exercise Physiology and Beyond

Conventionally viewed as energy storage depots, lipid droplets (LDs) play a central role in muscle lipid metabolism and intracellular signaling, as recognized by recent advances in our biological understanding. Specific subpopulations of muscle LDs, defined by location and associated proteins, are responsible for distinct biological functions. In this review, the traditional view of muscle LDs is examined, and the emerging role of LDs in intracellular signaling is highlighted. The effects of chronic and acute exercise on muscle LD metabolism and signaling is discussed. In conclusion, future directions for muscle LD research are identified. The primary focus will be on human studies, with inclusion of select animal/cellular/non-muscle studies as appropriate, to provide the underlying mechanisms driving the observed findings.

Maternal overnutrition impairs offspring's insulin sensitivity: A systematic review and meta-analysis

This systematic review and meta‐analysis aimed to investigate the association between maternal overnutrition and offspring's insulin sensitivity—following the Preferred Reporting Items for Systematic Reviews and Meta‐analyses statement. Studies published in English before April 22, 2019, were identified through searches of four medical databases. After selection, 15 studies aiming to explore the association between prepregnancy body mass index (ppBMI) or gestational weight gain (GWG) of non‐diabetic mothers and their offspring's insulin sensitivity (fasting insulin or glucose level and Homeostatic Measurement Assessment for Insulin Resistance [HOMA‐IR]) were included in the meta‐analysis. Associations of ppBMI and GWG with offspring's insulin sensitivity were analysed by pooling regression coefficients or standardized differences in means with 95% confidence intervals (CIs). Maternal ppBMI showed significant positive correlations with the level of both fasting insulin and HOMA‐IR in offspring (standardized regression coefficient for fasting insulin: 0.107, CI [0.053, 0.160], p < 0.001 and that for HOMA‐IR: 0.063, CI [0.006, 0.121], p = 0.031). However, the result of the analysis on coefficients adjusted for offspring's actual anthropometry (BMI and adiposity) was not significant. Independent from ppBMI, GWG tended to show a positive correlation with insulin level, but not after adjustment for offspring's anthropometry. Offspring of mothers with excessive GWG showed significantly higher HOMA‐IR than those of mothers with optimal GWG (p = 0.004). Our results demonstrate that both higher ppBMI and GWG increase the risk of offspring's insulin resistance, but the effect of ppBMI on insulin sensitivity in offspring may develop as consequence of their adiposity.

Predicting Skeletal Muscle and Whole-Body Insulin Sensitivity Using NMR-Metabolomic Profiling

PURPOSE

Abnormal lipoprotein and amino acid profiles are associated with insulin resistance and may help to identify this condition. The aim of this study was to create models estimating skeletal muscle and whole-body insulin sensitivity using fasting metabolite profiles and common clinical and laboratory measures.

MATERIAL AND METHODS

The cross-sectional study population included 259 subjects with normal or impaired fasting glucose or type 2 diabetes in whom skeletal muscle and whole-body insulin sensitivity (M-value) were measured during euglycemic hyperinsulinemic clamp. Muscle glucose uptake (GU) was measured directly using [18F]FDG-PET. Serum metabolites were measured using nuclear magnetic resonance (NMR) spectroscopy. We used linear regression to build the models for the muscle GU (Muscle-insulin sensitivity index [ISI]) and M-value (whole-body [WB]-ISI). The models were created and tested using randomly selected training (n = 173) and test groups (n = 86). The models were compared to common fasting indices of insulin sensitivity, homeostatic model assessment-insulin resistance (HOMA-IR) and the revised quantitative insulin sensitivity check index (QUICKI).

RESULTS

WB-ISI had higher correlation with actual M-value than HOMA-IR or revised QUICKI (ρ = 0.83 vs -0.67 and 0.66; P < 0.05 for both comparisons), whereas the correlation of Muscle-ISI with the actual skeletal muscle GU was not significantly stronger than HOMA-IR's or revised QUICKI's (ρ = 0.67 vs -0.58 and 0.59; both nonsignificant) in the test dataset.

CONCLUSION

Muscle-ISI and WB-ISI based on NMR-metabolomics and common laboratory measurements from fasting serum samples and basic anthropometrics are promising rapid and inexpensive tools for determining insulin sensitivity in at-risk individuals.

Inactivity and Skeletal Muscle Metabolism: A Vicious Cycle in Old Age

Aging is an inevitable and gradually progressive process affecting all organs and systems. The musculoskeletal system makes no exception, elderly exhibit an increased risk of sarcopenia (low muscle mass),dynapenia (declining muscle strength), and subsequent disability. Whereas in recent years the subject of skeletal muscle metabolic decline in the elderly has been gathering interest amongst researchers, as well as medical professionals, there are many challenges yet to be solved in order to counteract the effects of aging on muscle function efficiently. Noteworthy, it has been shown that aging individuals exhibit a decline in skeletal muscle metabolism, a phenomenon which may be linked to a number of predisposing (risk) factors such as telomere attrition, epigenetic changes, mitochondrial dysfunction, sedentary behavior (leading to body composition alterations), age-related low-grade systemic inflammation (inflammaging), hormonal imbalance, as well as a hypoproteic diet (unable to counterbalance the repercussions of the age-related increase in skeletal muscle catabolism). The present review aims to discuss the relationship between old age and muscle wasting in an effort to highlight the modifications in skeletal muscle metabolism associated with aging and physical activity.

Impact of Endurance and Resistance Training on Skeletal Muscle Glucose Metabolism in Older Adults

Aging is associated with insulin resistance and the development of type 2 diabetes. While this process is multifaceted, age-related changes to skeletal muscle are expected to contribute to impaired glucose metabolism. Some of these changes include sarcopenia, impaired insulin signaling, and imbalances in glucose utilization. Endurance and resistance exercise training have been endorsed as interventions to improve glucose tolerance and whole-body insulin sensitivity in the elderly. While both types of exercise generally increase insulin sensitivity in older adults, the metabolic pathways through which this occurs can differ and can be dependent on preexisting conditions including obesity and type 2 diabetes. In this review, we will first highlight age-related changes to skeletal muscle which can contribute to insulin resistance, followed by a comparison of endurance and resistance training adaptations to insulin-stimulated glucose metabolism in older adults.

Leucine Supplementation Does Not Alter Insulin Sensitivity in Prefrail and Frail Older Women following a Resistance Training Protocol

BACKGROUND

Frailty is a clinical condition associated with loss of muscle mass and strength (sarcopenia). Although sarcopenia has multifactorial causes, it might be partly attributed to a blunted response to anabolic stimuli. Leucine acutely increases muscle protein synthesis, and resistance training (RT) is the strongest stimuli to counteract sarcopenia and was recently shown to improve insulin sensitivity (IS) in frail older women. Discrepancies exist regarding whether chronic supplementation of leucine in conjunction with RT can improve muscle mass and IS.

OBJECTIVE

The aim of this double-blinded placebo-controlled study was to determine the effects of leucine supplementation and RT on IS in prefrail and frail older women.

METHODS

Using the Fried criteria, 19 nondiabetic prefrail (1-2 criteria) and frail (≥3 criteria) older women (77.5 ± 1.3 y; body mass index (kg/m2): 25.1 ± 0.9) underwent a 3-mo intervention of RT 3 times/wk with protein-optimized diet of 1.2 g·kg-1·d-1 and 7.5 g·d-1 of l-leucine supplementation compared with placebo l-alanine. Pre-/postintervention primary outcomes were fasting plasma glucose, serum insulin, and 4-h responses to a standard meal of complete liquid formula. Secondary outcomes of resting energy expenditure using indirect calorimetry and body composition using dual-energy X-ray absorptiometry were obtained. Paired t tests analyzed pooled data, and 2-factor repeated-measures ANOVA determined supplementation, training, and interaction effects.

RESULTS

No significant time, group, or interaction effects were observed for postprandial areas under the curve of serum insulin or plasma glucose or for resting energy expenditure in l-leucine compared with l-alanine. Total lean body mass increased and percentage body fat decreased significantly for both groups postintervention (0.76 ± 0.13 and -0.92 ± 0.33 kg, respectively; time effect: P < 0.01).

CONCLUSIONS

IS was not affected by RT and leucine supplementation in nondiabetic prefrail and frail older women. Therefore, leucine supplementation does not appear to influence IS under these conditions. This trial was registered at clinicaltrials.gov as NCT01922167.

Association of Glucose Fluctuations with Sarcopenia in Older Adults with Type 2 Diabetes Mellitus

Type 2 diabetes mellitus accelerates loss of muscle mass and strength. Patients with Alzheimer’s disease (AD) also show these conditions, even in the early stages of AD. The mechanism linking glucose management with these muscle changes has not been elucidated but has implications for clarifying these associations and developing preventive strategies to maintain functional capacity. This study included 69 type 2 diabetes patients with a diagnosis of cognitive impairment (n = 32) and patients with normal cognition (n = 37). We investigated the prevalence of sarcopenia in diabetes patients with and without cognitive impairment and examined the association of glucose alterations with sarcopenia. Daily glucose levels were evaluated using self-monitoring of blood glucose, and we focused on the effects of glucose fluctuations, postprandial hyperglycemia, and the frequency of hypoglycemia on sarcopenia. Diabetes patients with cognitive impairment displayed a high prevalence of sarcopenia, and glucose fluctuations were independently associated with sarcopenia, even after adjusting for glycated hemoglobin A1c (HbA1c) levels and associated factors. In particular, glucose fluctuations were significantly associated with a low muscle mass, low grip strength, and slow walking speed. Our observation suggests the importance of glucose management by considering glucose fluctuations to prevent the development of disability.

Molecular imaging of diabetes and diabetic complications: Beyond pancreatic β-cell targeting

Diabetes is a chronic non-communicable disease affecting over 400 million people worldwide. Diabetic patients are at a high risk of various complications, such as cardiovascular, renal, and other diseases. The pathogenesis of diabetes (both type 1 and type 2 diabetes) is associated with a functional impairment of pancreatic β-cells. Consequently, most efforts to manage and prevent diabetes have focused on preserving β-cells and their function. Advances in imaging techniques, such as magnetic resonance imaging, magnetic resonance spectroscopy, positron emission tomography, and single-photon-emission computed tomography, have enabled noninvasive and quantitative detection and characterization of the population and function of β-cells in vivo. These advantages aid in defining and monitoring the progress of diabetes and determining the efficacy of anti-diabetic therapies. Beyond β-cell targeting, molecular imaging of biomarkers associated with the development of diabetes, e.g., lymphocyte infiltration, insulitis, and metabolic changes, may also be a promising strategy for early detection of diabetes, monitoring its progression, and occurrence of complications, as well as facilitating exploration of new therapeutic interventions. Moreover, molecular imaging of glucose uptake, production and excretion in specified tissues is critical for understanding the pathogenesis of diabetes. In the current review, we summarize and discuss recent advances in noninvasive imaging technologies for imaging of biomarkers beyond β-cells for early diagnosis of diabetes, investigation of glucose metabolism, and precise diagnosis and monitoring of diabetic complications for better management of diabetic patients.

Dynamic changes in p66Shc mRNA expression in peripheral blood mononuclear cells following resistance training intervention in old frail women born to obese mothers: a pilot study

The p66Shc gerontogene may affect healthspan by promoting fat accumulation. We assessed changes of p66Shc-mRNA in peripheral tissues in relation to maternal obesity and the moderating effects of resistance-training (RT) exercise in elderly frail women. Thirty-seven women participated in a 4-month RT program. Twenty were offspring of lean/normal weight mothers and 17 were offspring of overweight/obese mothers (OOM). P66Shc was assessed in peripheral blood mononuclear cells (PBMC) and in subcutaneous adipose tissue (SAT) before and after RT. Overall, OOM showed elevated p66Shc mRNA levels in the PBMC. Independently from maternal obesity, following RT there was a decrease in p66Shc expression in PBMC but not in SAT, particularly in subjects with a high body mass index. Results suggest that maternal obesity has long-term effects on the expression of genes involved in mitochondrial function and fat deposition and that RT modifies p66Shc expression in PBMC with greater effects in obese subjects.ClinicalTrials.gov ID: NCT01931540.

Insulin sensitivity linked skeletal muscle Nr4a1 DNA methylation is programmed by the maternal diet and modulated by voluntary exercise in mice

Perinatal maternal high-fat consumption is known to increase the obesity and type 2 diabetes susceptibility and to impair exercise performance in the offspring. We hypothesize that epigenetic modifications in the skeletal muscle are partly responsible for this phenotype. To detect skeletal muscle genes affected by maternal nutrition, male offspring of low-fat (LF) and high-fat (HF) diet fed dams (BL6 mice) received LF diet upon weaning and were sacrificed at 6 or 25 weeks of age. Gene expression of Musculus quadriceps was investigated by microarray analysis revealing an up-regulation of the nuclear receptor Nr4a1 by maternal HF feeding. This was accompanied by promoter hypomethylation of CpG_-1408 which correlated with increased Nr4a1 gene expression at both ages. Offspring voluntary exercise training (by supplying running wheels from 7 to 25 weeks of age) normalized Nr4a1 methylation and gene expression respectively, and ameliorated the negative effects of maternal HF feeding on insulin sensitivity. Overall, Nr4a1 gene expression in skeletal muscle correlated with higher insulin levels during an oral glucose tolerance test and could, therefore, be involved in programming type 2 diabetes susceptibility in offspring exposed to perinatal high fat diet.

Lipid modulation of skeletal muscle mass and function

Loss of skeletal muscle mass is a characteristic feature of various pathologies including cancer, diabetes, and obesity, as well as being a general feature of ageing. However, the processes underlying its pathogenesis are not fully understood and may involve multiple factors. Importantly, there is growing evidence which supports a role for fatty acids and their derived lipid intermediates in the regulation of skeletal muscle mass and function. In this review, we discuss evidence pertaining to those pathways which are involved in the reduction, increase and/or preservation of skeletal muscle mass by such lipids under various pathological conditions, and highlight studies investigating how these processes may be influenced by dietary supplementation as well as genetic and/or pharmacological intervention.

Circulating Docosahexaenoic Acid Associates with Insulin-Dependent Skeletal Muscle and Whole Body Glucose Uptake in Older Women Born from Normal Weight Mothers

BACKGROUND

Obesity among pregnant women is common, and their offspring are predisposed to obesity, insulin resistance, and diabetes. The circulating metabolites that are related to insulin resistance and are associated with this decreased tissue-specific uptake are unknown. Here, we assessed metabolite profiles in elderly women who were either female offspring from obese mothers (OOM) or offspring of lean mothers (OLM). Metabolic changes were tested for associations with metrics for insulin resistance.

METHODS

Thirty-seven elderly women were separated into elderly offspring from obese mothers (OOM; n = 17) and elderly offspring from lean/normal weight mothers (OLM; n = 20) groups. We measured plasma metabolites using proton nuclear magnetic resonance (¹H-NMR) and insulin-dependent tissue-specific glucose uptake in skeletal muscle was assessed. Associations were made between metabolites and glucose uptake.

RESULTS

Compared to the OLM group, we found that the docosahexaenoic acid percentage of the total long-chain n-3 fatty acids (DHA/FA) was significantly lower in OOM (p = 0.015). DHA/FA associated significantly with skeletal muscle glucose uptake (GU) (p = 0.031) and the metabolizable glucose value derived from hyperinsulinemic-euglycemic clamp technique (M-value) in the OLM group only (p = 0.050).

CONCLUSIONS

DHA/FA is associated with insulin-dependent skeletal muscle glucose uptake and this association is significantly weakened in the offspring of obese mothers.

Bone mineral density is increased after a 16-week resistance training intervention in elderly women with decreased muscle strength

OBJECTIVE

Non-pharmacological interventions are important in reducing risk for osteoporotic fractures. We investigated the effects of a 16-week individualized resistance training intervention on bone mineral density (BMD), bone turnover markers and 10-year relative risk (RR) for osteoporotic fracture.

DESIGN

Interventional study with a follow-up.

METHODS

In total, 37 elderly women (mean age 71.9 ± 3.1 years) with decreased muscle strength participated in the resistance training intervention three times per week with 60 min per session for 16 weeks under the supervision of a licensed physiotherapist. Total hip BMD with quantitative CT, bone markers (sclerostin, osteocalcin, CTX, PINP, IGF-1, 25(OH)-D) and 10-year RR for osteoporotic fracture were measured at baseline, post-intervention and at 1-year follow-up after the end of the intervention. Eleven age- and sex-matched controls did not participate in the intervention but were studied at baseline and at 1-year follow-up.

RESULTS

Resistance training seemed to increase total hip BMD by 6% (P = 0.005). Sclerostin (P < 0.001) and total osteocalcin (P = 0.04) increased while other bone markers remained unchanged. A 10-year RR for major osteoporotic and hip fracture remained unchanged. At follow-up total hip BMD (P < 0.001) decreased back to the baseline level with a simultaneous decrease in serum sclerostin (P = 0.045), CTX (P < 0.001) and an increase in 25(OH)-D (P < 0.001), 10-year RR for major osteoporotic (P = 0.002) and hip fracture (P = 0.01).

CONCLUSIONS

Our findings suggest an important role of continuous supervised resistance training for the prevention of osteoporotic fractures in elderly women with decreased muscle strength.

Femoral Bone Marrow Insulin Sensitivity Is Increased by Resistance Training in Elderly Female Offspring of Overweight and Obese Mothers

Bone marrow insulin sensitivity may be an important factor for bone health in addition to bone mineral density especially in insulin resistant conditions. First we aimed to study if prenatal maternal obesity plays a role in determining bone marrow insulin sensitivity in elderly female offspring. Secondly we studied if a four-month individualized resistance training intervention increases bone marrow insulin sensitivity in elderly female offspring and whether this possible positive outcome is regulated by the offspring’s mother’s obesity status. 37 frail elderly females (mean age 71.9 ± 3.1 years) of which 20 were offspring of lean/normal-weight mothers (OLM, maternal BMI ≤ 26.3 kg/m2) and 17 were offspring of obese/overweight mothers (OOM, maternal BMI ≥ 28.1 kg/m2) were studied before and after a four-month individualized resistance training intervention. Nine age- and sex-matched non-frail controls (maternal BMI ≤ 26.3 kg/m2) were studied at baseline. Femoral bone marrow (FBM) and vertebral bone marrow (VBM) insulin sensitivity were measured using [18F]fluoro-2-deoxy-D-glucose positron emission tomography with computer tomography under hyperinsulinemic euglycemic clamp. We found that bone marrow insulin sensitivity was not related to maternal obesity status but FBM insulin sensitivity correlated with whole body insulin sensitivity (R = 0.487, p = 0.001). A four-month resistance training intervention increased FBM insulin sensitivity by 47% (p = 0.006) only in OOM, while VBM insulin sensitivity remained unchanged regardless of the maternal obesity status. In conclusion, FBM and VBM glucose metabolism reacts differently to a four-month resistance training intervention in elderly women according to their maternal obesity status.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01931540.

Developmental Origins of Health and Disease - from a small body size at birth to epigenetics

The Developmental Origins of Health and Disease (DOHaD) hypothesis proposes that several non-communicable diseases have their origins in prenatal life and in early childhood. This is believed to work through programming, an insult, taking place at a sensitive period of development, may have lifelong consequences, increasing and programming disease risk later in life. The Helsinki Birth Cohort Study (HBCS) has been focusing upon the importance of factors active during periods in early life and their influence on later health in 20,431 people born 1924-44. This review will focus upon findings from the HBCS over the past 20 years. Early growth patterns associated with coronary heart disease, type 2 diabetes and other health outcomes are described. The long-term health impact of maternal adiposity is also discussed. Potential underlying mechanisms explaining the associations are discussed including epigenetic factors. Key messages Several non-communicable diseases - including coronary heart disease and type 2 diabetes - have their origins in early life. Early life programming during sensitive periods of development may permanently program future health and disease risk. Optimizing the health and lifestyle of women of reproductive age will have positive health consequences for their offspring.

Resistance training enhances insulin suppression of endogenous glucose production in elderly women

An altered prenatal environment during maternal obesity predisposes offspring to insulin resistance, obesity, and their consequent comorbidities, type 2 diabetes and cardiovascular disease. Telomere shortening and frailty are additional risk factors for these conditions. The aim of this study was to evaluate the effects of resistance training on hepatic metabolism and ectopic fat accumulation. Thirty-five frail elderly women, whose mothers' body mass index (BMI) was known, participated in a 4-mo resistance training program. Endogenous glucose production (EGP) and hepatic and visceral fat glucose uptake were measured during euglycemic hyperinsulinemia with [(18)F]fluorodeoxyglucose and positron emission tomography. Ectopic fat was measured using magnetic resonance spectroscopy and imaging. We found that the training intervention reduced EGP during insulin stimulation [from 5.4 (interquartile range 3.0, 7.0) to 3.9 (-0.4, 6.1) μmol·kg body wt(-1)·min(-1), P = 0.042] in the whole study group. Importantly, the reduction was higher among those whose EGP was more insulin resistant at baseline (higher than the median) [-5.6 (7.1) vs. 0.1 (5.4) μmol·kg body wt(-1)·min(-1), P = 0.015]. Furthermore, the decrease in EGP was associated with telomere elongation (r = -0.620, P = 0.001). The resistance training intervention did not change either hepatic or visceral fat glucose uptake or the amounts of ectopic fat. Maternal obesity did not influence the studied measures. In conclusion, resistance training improves suppression of EGP in elderly women. The finding of improved insulin sensitivity of EGP with associated telomere lengthening implies that elderly women can reduce their risk for type 2 diabetes and cardiovascular disease with resistance training.