Effect of calorie restriction with or without exercise on insulin sensitivity, beta-cell function, fat cell size, and ectopic lipid in overweight subjects

Intermittent fasting versus continuous caloric restriction for glycemic control and weight loss in type 2 diabetes: A traditional review

Type 2 Diabetes Mellitus (T2DM) represents a major global health issue, with its incidence anticipated to increase markedly in the forthcoming decades. Efficient non-pharmacological therapies, especially dietary approaches, are essential for regulating glycemic control and facilitating weight reduction. Intermittent Fasting (IF) and Continuous Caloric Restriction (CCR) are two well researched methodologies, but their relative effectiveness and enduring advantages continue to be topics of active discussion. This review systematically assesses and contrasts the impacts of intermittent fasting (IF) and continuous calorie restriction (CCR) on glycemic regulation and weight reduction in persons with type 2 diabetes mellitus (T2DM), highlighting their short-term and long-term effects, safety profiles, and adherence rates. A thorough literature analysis was performed utilizing PubMed and Google Scholar, concentrating on papers published from 2000 to 2024. The review encompassed randomized controlled trials and observational studies that investigated the effects of intermittent fasting (IF) and continuous calorie restriction (CCR) on glycemic indicators (HbA1c, fasting glucose) and body weight. IF shown substantial short-term advantages, encompassing marked decreases in HbA1c levels, fasting glucose, and body weight. Mechanistic discoveries emphasized better insulin sensitivity, augmented fat metabolism, and autophagy as key aspects. In contrast, CCR was linked to enduring metabolic enhancements, including decreased visceral fat and improved insulin sensitivity. Nevertheless, both dietary approaches demonstrated constraints.

Regulation of metabolic pathways genes and the effects of very low-calorie diet on insulin resistance and fatty acid profiles in obese patients undergoing bariatric surgery

Objectives

To evaluate the effects of a very-low-calorie diet (VLCD) on insulin resistance (IR), metabolic gene expression, and fatty acid profiles in obese patients (body mass index [BMI] ≥ 30 kg/m2) undergoing bariatric surgery compared to age- and sex-matched nonobese controls (BMI ≤ 25 kg/m2) undergoing elective abdominal surgery.

Methods

A total of 38 participants (21 obese and 17 nonobese controls) were recruited for this study. Obese patients underwent VLCD (800 kcal/day) for four weeks before surgery. Fasting blood samples and tissue biopsies were collected during surgery. Key parameters included IR (measured using HOMA-IR), metabolic gene expression (quantified via RT-PCR), and fatty acid composition (analyzed by gas chromatography). Data were compared between pre- and post-VLCD groups in the obese cohort.

Results

GLUT4 expression was reduced (1.57-fold, p = 0.025), whereas PDK4 (3.9-fold, p = 0.002), CPT1 (2.5-fold, p = 0.013), and AMPK (twofold, p = 0.004) expression were Correlation analysis revealed that GLUT4 was negatively correlated with BMI (r = -0.85), glucose (r = -0.94), and IR (r = -0.79), CPT1 was positively correlated with these parameters (BMI: r = 0.84, glucose: r = 0.92, IR: r = 0.82). VLCD significantly reduced monounsaturated fatty acids, including alpha-linolenic acid (p = 0.03) and erucic acid (p = 0.019). Postsurgical improvements included reductions in BMI (Δ = 6.21, p < 0.0001), glucose level (Δ = 6.94, p = 0.0007), and IR (Δ = 10.19, p = 0.0039).

Conclusion

VLCD modulated metabolic gene expression and fatty acid profiles, enhancing IR and metabolic health both pre- and post-surgery. This represents a critical strategy for optimizing the outcomes of obese patients undergoing bariatric surgery.

Supplementary information

The online version contains supplementary material available at 10.1007/s40200-025-01625-5.

Weight loss in MASLD restores the balance of liver fatty acid sources

BACKGROUNDLipogenesis contributes substantially to the pathological accumulation of intrahepatic triacylglycerol (IHTG) in metabolic dysfunction-associated steatotic liver disease (MASLD). Since hepatic lipogenesis is highly sensitive to energy intake, we hypothesized that mechanisms of MASLD regression induced by weight loss would be driven by a marked reduction in the lipogenic pathway.METHODSOverweight adults with high liver fat (HighLF; n = 9; IHTG ≥ 5.6% measured by 1H-magnetic resonance spectroscopy) or low (normal) liver fat (LowLF; n = 6; IHTG < 5.6%) received dietary counseling for 6 months and underwent comprehensive metabolic phenotyping during inpatient studies that captured fasting and fed states. Multiple stable isotopes were used to assess the contribution of lipogenesis, free fatty acids (FFAs), and dietary fat to IHTG.RESULTSBody weight loss (-10% ± 2%) reduced IHTG in individuals with MASLD (19.4% ± 3.6% to 4.5% ± 2.1%, P < 0.001). Insulin sensitivity improved significantly (46%, P < 0.01), while fasting FFA flux from adipose tissue was not different. VLDL-triacylglycerol (VLDL-TG) concentrations fell by 38% (P = 0.02) because of a 67% reduction in contribution from lipogenesis (P = 0.02), whereas the absolute contributions from FFAs and dietary fat to VLDL-TG were not different. Reduced lipogenesis was significantly associated with loss of IHTG.CONCLUSIONThese data underscore the primary role of lipogenesis in MASLD pathology and highlight the importance of controlling this pathway through treatment strategies.TRIAL REGISTRATIONClinicalTrials.gov (NCT01371396).FUNDINGNational Institutes of Health (NIH) grant RL1DK081187; Task Force for Obesity Research at Southwestern (TORS) NIH UL1DE019584; and Clinical and Translational Science Award NIH/National Center for Advancing Translational Sciences UL1-RR024982.

A fasting-mimicking diet programme reduces abdominal adipose tissue while preserving abdominal muscle mass in persons with type 2 diabetes

BACKGROUND AND AIM

This study evaluated the effects of a fasting-mimicking diet (FMD) programme alongside usual care on abdominal visceral- (aVAT) and subcutaneous (aSAT) adipose tissue, and abdominal muscle area (aMA) in persons with type 2 diabetes in primary care.

METHODS AND RESULTS

100 persons with type 2 diabetes using metformin and/or diet alone for glycemic control were randomly assigned to receive an FMD for 5 consecutive days each month plus usual care or usual care only for 12 months. The treatment effect of the FMD on aVAT, aSAT and aMA as well as associations between changes in aVAT, aSAT or aMA, and changes in metabolic parameters were assessed. 89 participants completed baseline visits including MRI. The adjusted estimated treatment effect after 12 months in the FMD group was a loss of 37.9 cm2 (95 % CI -54.7, to -21.0) in aVAT, 20.9 cm2 (95 %CI -34.5 to -7.3) in aSAT and -1.6 cm2 (95 % CI -4.6 to 1.4) in aMA compared to the control group. Changes in aVAT and aSAT were strongly associated with change in HbA1c and moderately with other metabolic parameters.

CONCLUSIONS

A 12-month FMD programme reduced both aVAT and aSAT, while aMA remained unaffected compared to controls in persons with type 2 diabetes. The decline in aVAT and aSAT was associated with a reduction of several metabolic parameters, including HbA1c. A monthly FMD programme yields various health benefits in type 2 diabetes and appears to be a valuable treatment option as adjunct to usual care.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03811587, 05-11-2018.

Multi-omic analysis of biological aging biomarkers in long-term calorie restriction and endurance exercise practitioners: A cross-sectional study

Calorie restriction (CR) and physical exercise (EX) are well-established interventions known to extend health span and lifespan in animal models. However, their impact on human biological aging remains unclear. With recent advances in omics technologies and biological age (BioAge) metrics, it is now possible to assess the impact of these lifestyle interventions without the need for long-term follow-up. This study compared BioAge biomarkers in 41 middle-aged and older adult long-term CR practitioners, 41 age- and sex-matched endurance athletes (EX), and 35 sedentary controls consuming Western diets (WD), through PhenoAge: a composite score derived from nine blood-biomarkers. Additionally, a subset of participants (12 CR, 11 EX, and 12 WD) underwent multi-omic profiling, including DNA methylation and RNAseq of colon mucosa, blood metabolomics, and stool metagenomics. A group of six young WD subjects (yWD) served as a reference for BioAge calculation using Mahalanobis distance across six omic layers. The results demonstrated consistently lower BioAge biomarkers in both CR and EX groups compared to WD controls across all layers. CR participants exhibited lower BioAge in gut microbiome and blood-derived omics, while EX participants had lower BioAge in colon mucosa-derived epigenetic and transcriptomic markers, suggesting potential tissue-specific effects. Multi-omic pathway enrichment analyses suggested both shared and intervention-specific mechanisms, including oxidative stress and basal transcription as common pathways, with ether lipid metabolism uniquely enriched in CR. Despite limitations due to sample size, these findings contribute to the broader understanding of the potential anti-aging effects of CR and EX, offering promising directions for further research.

The Asian Pacific association for the study of the liver clinical practice guidelines for the diagnosis and management of metabolic dysfunction-associated fatty liver disease

Metabolic dysfunction-associated fatty liver disease (MAFLD) affects over one-fourth of the global adult population and is the leading cause of liver disease worldwide. To address this, the Asian Pacific Association for the Study of the Liver (APASL) has created clinical practice guidelines focused on MAFLD. The guidelines cover various aspects of the disease, such as its epidemiology, diagnosis, screening, assessment, and treatment. The guidelines aim to advance clinical practice, knowledge, and research on MAFLD, particularly in special groups. The guidelines are designed to advance clinical practice, to provide evidence-based recommendations to assist healthcare stakeholders in decision-making and to improve patient care and disease awareness. The guidelines take into account the burden of clinical management for the healthcare sector.

The Impact of Exercise Training Plus Dietary Interventions on Ectopic Fat in Population with Overweight/Obesity with and without Chronic Disease: A Systematic Review, Meta-analysis, and Metaregression of Randomized Clinical Trials

Background

The growing prevalence of obesity and related chronic diseases has led to increased interest in interventions targeting ectopic fat reduction to which its accumulation is linked to metabolic dysfunction.

Objectives

This study aimed to evaluate the effects of combined exercise training combined with dietary interventions compared with dietary interventions alone on ectopic fat [visceral fat area (VFA), liver fat, intramuscular fat (IMF), pancreatic fat, renal sinus fat, and pericardial and epicardial fats] in adults with overweight and obesity, both with and without chronic diseases.

Methods

Web of Science, Scopus, and PubMed were searched for original articles up to 1 March, 2024, that included exercise compared with control interventions on body weight and ectopic fat in adults with overweight or obesity. Weighted mean differences (WMD) for body weight, liver fat, pancreatic fat, and renal sinus fat and standardized mean differences (SMD) for VFA, IMF, pericardial and epicardial fats, and 95% confidence intervals were determined using random-effects models.

Results

Thirty-two studies, including 1488 participants and 38 intervention groups, met the inclusion criteria. The combined intervention of exercise and diet did not reduce body weight (WMD = -0.23 kg, P = 0.180), liver fat (WMD = 0.05%, P = 0.730), IMF (SMD = -0.08, P = 0.640), pericardial and epicardial fats (SMD = -0.12, P = 0.280), pancreatic fat (WMD = -0.24%, P = 0.370), and renal sinus fat (WMD = 0.01 cm2, P = 0.170) when compared with a diet-only group. Interestingly, exercise combined with diet significantly reduced VFA in participants with obesity (SMD = -0.12, P = 0.040) and healthy males (SMD = -0.33, P = 0.001) when compared with a diet-only group.

Conclusions

The findings suggest that combined exercise and dietary interventions did not lead to significant reductions in most ectopic fat depots when compared with diet alone. However, a modest reduction in VFA was observed in participants with obesity and healthy males. These results highlight the nuanced impact of exercise in combination with dietary interventions and the need to consider specific fat depots and participant characteristics in obesity management strategies.The trial was registered at PROSPERO as CRD42024546770.

Intense Caloric Restriction from Birth Protects the Heart Against Ischemia/Reperfusion Injury and Reduces Reactive Oxygen Species in Ovariectomized Rats

This study investigates the cardioprotective effects of intense caloric restriction (ICR) from birth in ovariectomized rats, a model of estrogen deficiency mimicking menopause. Our findings demonstrate that ICR significantly improved both basal and post-ischemic cardiac function, even in the absence of estrogens. The restricted animals exhibited enhanced cardiac contractility and relaxation, particularly after ischemia/reperfusion (I/R) injury, with superior functional recovery compared to control groups. Notably, ICR reduced key cardiometabolic risk factors, including blood pressure, heart rate, and adiposity, while improving glucose tolerance and insulin sensitivity. Additionally, while mitochondrial biogenesis remained unaffected, ICR preserved mitochondrial integrity by reducing the number of damaged mitochondria. This was linked to a reduction in oxidative stress, as evidenced by lower reactive oxygen species (ROS) production in the hearts of restricted animals. These results suggest that ICR offers a protective effect against cardiovascular dysfunction induced by estrogen depletion, potentially through enhanced antioxidant defenses and mitochondrial protection.

Efficacy of intermittent fasting on improving liver function in individuals with metabolic disorders: a systematic review and meta-analysis

BACKGROUND

Intermittent fasting (IF) can be an effective dietary therapy for weight loss and improving cardiometabolic health. However, there is scant evidence regarding the role of IF on indicators of liver function, particularly in adults with metabolic disorders. Therefore, we performed a systematic review and meta-analysis to investigate the effects of IF on liver function in adults with metabolic disorders.

METHODS

Three primary electronic databases including PubMed, Web of Science, and Scopus, were searched from inception to September 2024 to identify original studies that used IF interventions with or without control groups in adults with metabolic disorders. Inclusion criteria were (1) studies of human participants with metabolic diseases, (2) interventions that evaluated the effects of IF, (3) with or without a control group, and (4) measured liver fat, liver steatosis, liver fibrosis, or liver enzymes, including alanine aminotransferase (ALT) and aspartate aminotransferase (AST) as primary outcomes. Standardized mean differences (SMD) and 95% confidence intervals were calculated using random effects models. Heterogeneity was assessed using the Cochran's Q statistic and I-squared statistic (I2). Publication bias was assessed using the visual inspection of funnel plots and Egger's tests. The risk of bias was assessed using the PEDro scale and the NIH quality assessment tool.

RESULTS

A total 21 studies involving 1,226 participants with metabolic disorders were included in the meta-analysis. Overall, IF effectively decreased liver fat with a large effect size [SMD: -1.22 (95% CI: -1.63 to -0.80), p = 0.001], liver steatosis with a medium effect size [SMD: -0.73 (95% CI: -1.12 to -0.35), p = 0.001], ALT with a small effect size [SMD: -0.44 (95% CI: -0.58 to -0.30), p = 0.001], and AST with a small effect size [SMD: -0.30 (95% CI: -0.49 to -0.11), p = 0.001], but not liver fibrosis [SMD: -0.28 (95% CI: -0.59 to 0.02), p = 0.07]. Subgroup analyses showed that IF decreased liver fat and ALT significantly, independent of IF mode, participant age, health status, weight status, and intervention duration. IF significantly decreased liver fibrosis in those with obesity; and decreased AST following 5:2 diets, in middle-aged adults, adults with obesity, and regardless of health status or intervention duration.

CONCLUSIONS

IF seems to be an effective dietary therapy for improving liver function in adults with metabolic disorders, and many of liver function-related benefits occur regardless of IF mode, intervention duration, or participant health status.

LIMITATIONS

Significant heterogeneity, small numbers of studies and inclusion of non-randomized trials or single-group pre-post trials were the main limitation of our meta-analysis. Further randomized clinical trials are needed to elucidate the effects of IF on liver function in adults with metabolic disorders.

Calorie restriction induces mandible bone loss by regulating mitochondrial function

Caloric restriction (CR), commonly used as both a lifestyle choice and medical strategy, has been shown to adversely impact appendicular bone mass. However, its influence on alveolar bone health and the underlying mechanisms remain poorly understood. In this study, 8-week-old C57BL/6 J mice were fed with 30 % CR for 8 weeks. Micro-architecture, histologic parameters, and in vitro trajectories of osteoblast and adipocyte differentiation were examined. To further explore the underlying mechanisms, metabolic cages and in vitro bioenergetics were performed. Our results showed that 8 weeks of CR led to trabecular and cortical bone loss in the mandibles of female mice. CR in female mice decreased bone formation and bone resorption activities but induced adiposity in the mandibles. After CR, the adipogenesis in mesenchymal cells from orofacial bones (OMSCs) was greatly accelerated, whereas osteogenic differentiation was reduced in females. Undifferentiated CR OMSCs showed marked suppression in ATP production rates from mitochondria in female mice. ATP production rates decreased after osteogenesis but were upregulated during adipogenesis in female mice. Conversely, the generation of reactive oxygen species (ROS) was heightened during both osteoblastic and adipogenic differentiation in female CR groups. Collectively, our study indicated that CR could cause significant bone loss in the mandibles of female mice, almost certainly related to a reduced ATP supply and the unregulated generation of ROS.

The Causal Role of Ectopic Fat Deposition in the Pathogenesis of Metabolic Syndrome

Consuming a "modern" Western diet and overnutrition may increase insulin secretion. Additionally, nutrition-mediated hyperinsulinemia is a major driver of ectopic fat deposition. The global prevalence of metabolic syndrome is high and growing. Within this context, people with congenital lipodystrophy often experience a severe form of metabolic syndrome. Evidence is increasingly supporting that subtle partial lipodystrophy plays an important role in the development of metabolic syndrome in the general population. In individuals in the general population with subtle partial lipodystrophy, as well as in those with congenital lipodystrophy, the subcutaneous adipose tissues are unable to accommodate surplus energy intake. In both conditions, (excess) fat is directed toward the liver, pancreas, and muscles, where it is deposited as ectopic fat, as this fat can no longer be stored in the "safe" subcutaneous fat depots. Ectopic fat depositions cause insulin resistance in the liver and muscles, as well as β-cell dysfunction in the pancreas. Support of a direct pathological role of ectopic fat deposition in this condition is further provided by the rapid normalization of hepatic insulin sensitivity and improvement in pancreatic β-cell function after marked reductions in ectopic fat depositions. Thus, ectopic fat deposition in the liver, pancreas, and muscles may play a causal role in the pathogenesis of metabolic syndrome even in the general population. As such, the prevention of ectopic fat deposition may reduce the risk of metabolic syndrome and mitigate its effects.

Evaluating the Association of Anthropometric Indices With Total Cholesterol in a Large Population Using Data Mining Algorithms

BACKGROUND

Unbalanced levels of serum total cholesterol (TC) and its subgroups are called dyslipidemia. Several anthropometric indices have been developed to provide a more accurate assessment of body shape and the health risks associated with obesity. In this study, we used the random forest model (RF), decision tree (DT), and logistic regression (LR) to predict total cholesterol based on new anthropometric indices in a sex-stratified analysis.

METHOD

Our sample size was 9639 people in which anthropometric parameters were measured for the participants and data regarding the demographic and laboratory data were obtained. Aiding the machine learning, DT, LR, and RF were drawn to build a measurement prediction model.

RESULTS

Anthropometric and other related variables were compared between both TC <200 and TC ≥200 groups. In both males and females, Lipid Accumulation Product (LAP) had the greatest effect on the risk of TC increase. According to results of the RF model, LAP and Visceral Adiposity Index (VAI) were significant variables for men. VAI also had a stronger correlation with HDL-C and triglyceride. We identified specific anthropometric thresholds based on DT analysis that could be used to classify individuals at high or low risk of elevated TC levels. The RF model determined that the most important variables for both genders were VAI and LAP.

CONCLUSION

We tend to present a picture of the Persian population's anthropometric factors and their association with TC level and possible risk factors. Various anthropometric indices indicated different predictive power for TC levels in the Persian population.

Effect of abrupt and gradual calorie restriction regimens on biochemical and behavioral markers in obese mice model

Background: Although Calorie Restriction (CR) is primarily considered in obesity management, behavioral studies of CR and its methodology of implementation are not well-defined. Objective: The study aimed to determine the efficacy of the extensively researched method of CR-abrupt calorie restriction (ACR) and a newly proposed gradual calorie restriction (GCR) in terms of body weight, behavioral and biochemical parameters in the obese animal model-C57BL/6J mice. Design: Male obese mice were subjected to GCR regimen for 14 weeks which was compared and evaluated for anxiety-like behavior and stress levels with ACR. Plasma corticosterone was measured before initiation of CR and every three weeks following GCR and ACR, whereas plasma insulin was measured twice-after obesity induction and post 14 weeks of CR. The behavioral assessments were conducted before inducing CR and every three weeks following ACR and GCR. Results: A significant anxiety-like behavior and an increase in plasma corticosterone were observed in mice on GCR during the critical initial six weeks of CR (p < 0.05). Both groups showed a decrease in plasma glucose levels; however, the GCR group showed a significant reduction (p < 0.01). There was a significant decrease in social interaction in both groups with an increase in the latency period and a decrease in time spent with the stranger animal during the social interaction test (p < 0.05). Conclusion: The mice on GCR regimen demonstrated lesser anxiety-like behavior and low plasma corticosterone levels compared to those on ACR. This gives us a new avenue in CR research to evaluate the methodologies of implementing CR.

Obesity and MASLD: Is weight loss the (only) key to treat metabolic liver disease?

Metabolic dysfunction-associated steatotic liver disease (MASLD) closely associates with obesity and type 2 diabetes. Lifestyle intervention and bariatric surgery aiming at substantial weight loss are cornerstones of MASLD treatment by improving histological outcomes and reducing risks of comorbidities. Originally developed as antihyperglycemic drugs, incretin (co-)agonists and SGLT2 inhibitors also reduce steatosis and cardiorenovascular events. Certain incretin agonists effectively improve histological features of MASLD, but not fibrosis. Of note, beneficial effects on MASLD may not necessarily require weight loss. Despite moderate weight gain, one PPARγ agonist improved adipose tissue and MASLD with certain benefit on fibrosis in post-hoc analyses. Likewise, the first THRβ-agonist was recently provisionally approved because of significant improvements of MASLD and fibrosis. We here discuss liver-related and metabolic effects induced by different MASLD treatments and their association with weight loss. Therefore, we compare results from clinical trials on drugs acting via weight loss (incretin (co)agonists, SGLT2 inhibitors) with those exerting no weight loss (pioglitazone; resmetirom). Furthermore, other drugs in development directly targeting hepatic lipid metabolism (lipogenesis inhibitors, FGF21 analogs) are addressed. Although THRβ-agonism may effectively improve hepatic outcomes, MASLD treatment concepts should consider all cardiometabolic risk factors for effective reduction of morbidity and mortality in the affected people.

Comprehensive Strategies for Metabolic Syndrome: How Nutrition, Dietary Polyphenols, Physical Activity, and Lifestyle Modifications Address Diabesity, Cardiovascular Diseases, and Neurodegenerative Conditions

Several hallmarks of metabolic syndrome, such as dysregulation in the glucose and lipid metabolism, endothelial dysfunction, insulin resistance, low-to-medium systemic inflammation, and intestinal microbiota dysbiosis, represent a pathological bridge between metabolic syndrome and diabesity, cardiovascular, and neurodegenerative disorders. This review aims to highlight some therapeutic strategies against metabolic syndrome involving integrative approaches to improve lifestyle and daily diet. The beneficial effects of foods containing antioxidant polyphenols, intestinal microbiota control, and physical activity were also considered. We comprehensively examined a large body of published articles involving basic, animal, and human studie, as well as recent guidelines. As a result, dietary polyphenols from natural plant-based antioxidants and adherence to the Mediterranean diet, along with physical exercise, are promising complementary therapies to delay or prevent the onset of metabolic syndrome and counteract diabesity and cardiovascular diseases, as well as to protect against neurodegenerative disorders and cognitive decline. Modulation of the intestinal microbiota reduces the risks associated with MS, improves diabetes and cardiovascular diseases (CVD), and exerts neuroprotective action. Despite several studies, the estimation of dietary polyphenol intake is inconclusive and requires further evidence. Lifestyle interventions involving physical activity and reduced calorie intake can improve metabolic outcomes.

Physical Activity and Weight Loss Among Adults With Type 2 Diabetes and Overweight or Obesity: A Post Hoc Analysis of the Look AHEAD Trial

Importance

Prior findings from the Look AHEAD trial showed no significant reduction in the risk of cardiovascular events by lifestyle-induced weight loss among individuals with type 2 diabetes (T2D) and overweight or obesity. However, physical activity (PA) may modify the changes in cardiovascular risk associated with weight loss.

Objective

To examine the joint association of weight loss and PA with the risk of adverse cardiovascular events in patients with T2D and overweight or obesity.

Design, Setting, and Participants

This cohort study was a post hoc analysis of the Look AHEAD randomized clinical trial, which compared the cardiovascular effects of weight loss by intensive lifestyle intervention vs diabetes support and education among individuals with T2D and overweight or obesity. The study was conducted from June 2001 to September 2012, and participants were patients in the substudy of accelerometry-measured PA from 8 locations in the United States. Data were analyzed from June to August 2023.

Exposures

Body weight change and accelerometer-derived PA volume across the first 4 years.

Main Outcomes and Measures

The primary outcome was a composite cardiovascular outcome including cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for angina.

Results

Among a total of 1229 participants (mean [SD] age, 60 [7] years; 533 male [43%]), 333 (27%) achieved and maintained weight loss for the first 4 years. Among the individuals who maintained weight loss, 105 (32%) maintained high PA volume. During a median of 9.5 years of follow-up, 198 participants (16.1%) experienced the primary outcome. Compared with those with low PA volume and no weight loss (105 [15.8%]), maintaining high PA volume and weight loss was associated with a 61% lower risk of the primary end point (hazard ratio, 0.39; 95% CI, 0.19-0.81; P = .01). However, there was no significant difference in the risk of the primary end point among those with either weight loss only or high PA only. The multiplicative interaction between weight loss and PA for the risk of cardiovascular events was also significant (P for interaction = .01).

Conclusions and Relevance

In this cohort study, maintaining weight loss and higher PA volume was associated with a lower risk of the composite cardiovascular outcome. The findings suggest that the cardiovascular benefits of PA may vary and be enhanced by weight loss among individuals with T2D and overweight or obesity.

Predicting the 10-year incidence of dyslipidemia based on novel anthropometric indices, using data mining

BACKGROUND

The aim was to establish a 10-year dyslipidemia incidence model, investigating novel anthropometric indices using exploratory regression and data mining.

METHODS

This data mining study was conducted on people who were diagnosed with dyslipidemia in phase 2 (n = 1097) of the Mashhad Stroke and Heart Atherosclerotic Disorder (MASHAD) study, who were compared with healthy people in this phase (n = 679). The association of dyslipidemia with several novel anthropometric indices including Conicity Index (C-Index), Body Roundness Index (BRI), Visceral Adiposity Index (VAI), Lipid Accumulation Product (LAP), Abdominal Volume Index (AVI), Weight-Adjusted-Waist Index (WWI), A Body Shape Index (ABSI), Body Mass Index (BMI), Body Adiposity Index (BAI) and Body Surface Area (BSA) was evaluated. Logistic Regression (LR) and Decision Tree (DT) analysis were utilized to evaluate the association. The accuracy, sensitivity, and specificity of DT were assessed through the performance of a Receiver Operating Characteristic (ROC) curve using R software.

RESULTS

A total of 1776 subjects without dyslipidemia during phase 1 were followed up in phase 2 and enrolled into the current study. The AUC of models A and B were 0.69 and 0.63 among subjects with dyslipidemia, respectively. VAI has been identified as a significant predictor of dyslipidemias (OR: 2.81, (95% CI: 2.07, 3.81)) in all models. Moreover, the DT showed that VAI followed by BMI and LAP were the most critical variables in predicting dyslipidemia incidence.

CONCLUSIONS

Based on the results, model A had an acceptable performance for predicting 10 years of dyslipidemia incidence. Furthermore, the VAI, BMI, and LAP were the principal anthropometric factors for predicting dyslipidemia incidence by LR and DT models.

Nutrition and dietary restrictions in cancer prevention

The composition and pattern of dietary intake have emerged as key factors influencing aging, regeneration, and consequently, healthspan and lifespan. Cancer is one of the major diseases more tightly linked with aging, and age-related mortality. Although the role of nutrition in cancer incidence is generally well established, we are far from a consensus on how diet influences tumour development in different tissues. In this review, we will discuss how diet and dietary restrictions affect cancer risk and the molecular mechanisms potentially responsible for their effects. We will cover calorie restriction, intermittent fasting, prolonged fasting, fasting-mimicking diet, time-restricted eating, ketogenic diet, high protein diet, Mediterranean diet, and the vegan and vegetarian diets.

Navigating the Adipocyte Precursor Niche: Cell-Cell Interactions, Regulatory Mechanisms and Implications for Adipose Tissue Homeostasis

Support for stem cell self-renewal and differentiation hinges upon the intricate microenvironment termed the stem cell 'niche'. Within the adipose tissue stem cell niche, diverse cell types, such as endothelial cells, immune cells, mural cells, and adipocytes, intricately regulate the function of adipocyte precursors. These interactions, whether direct or indirect, play a pivotal role in governing the balance between self-renewal and differentiation of adipocyte precursors into adipocytes. The mechanisms orchestrating the maintenance and coordination of this niche are still in the early stages of comprehension, despite their crucial role in regulating adipose tissue homeostasis. The complexity of understanding adipocyte precursor renewal and differentiation is amplified due to the challenges posed by the absence of suitable surface receptors for identification, limitations in creating optimal ex vivo culture conditions for expansion and constraints in conducting in vivo studies. This review delves into the current landscape of knowledge surrounding adipocyte precursors within the adipose stem cell niche. We will review the identification of adipocyte precursors, the cell-cell interactions they engage in, the factors influencing their renewal and commitment toward adipocytes and the transformations they undergo during instances of obesity.

"Weight loss is my goal and being healthy is my goal… I can get over the hot flashes": a qualitative exploration of menopausal transition experiences and preferences for weight management among White women

OBJECTIVES

A qualitative research study design was used to (1) describe experiences of White women during the menopausal transition, and (2) identify barriers and facilitators for participating in a lifestyle program targeting weight management.

METHODS

Perimenopausal and postmenopausal White women who self-reported a desire to lose or maintain weight participated in focus groups. Women were queried about their past diet, exercise, and weight management practices; menopausal transition; and specific components and considerations for developing a lifestyle program for weight management. Thematic analysis was conducted on coded transcripts and four main themes emerged, each containing three to six subthemes.

RESULTS

Twenty-eight White women (age 54 ± 3 y, body mass index 31.4 ± 9.5 kg/m 2 ) were enrolled. Overall, women felt menopause was a major life event that coincided with weight gain and frustrating body changes. Women already engaged in many different types of exercises and diets to lose weight. Women also talked to healthcare professionals about menopause but were disappointed in the support they received. Women were interested in a lifestyle program that included menopause-specific education, which focused on results beyond weight, which was flexible to their busy lifestyle, and which provided opportunities to build camaraderie among other women experiencing menopause.

CONCLUSIONS

This cohort of White women were interested in receiving menopause information and improving their overall health as part of a lifestyle program targeting weight management during this transition. Building camaraderie with other women affected by menopause is important to women, as is creating a lifestyle program that is flexible with daily life.

Diet-induced Weight Loss and Phenotypic Flexibility Among Healthy Overweight Adults: A Randomized Trial

BACKGROUND

The capacity of an individual to respond to changes in food intake so that postprandial metabolic perturbations are resolved, and metabolism returns to its pre-prandial state, is called phenotypic flexibility. This ability may be a more important indicator of current health status than metabolic markers in a fasting state.

AIM

In this parallel randomized controlled trial study, an energy-restricted healthy diet and 2 dietary challenges were used to assess the effect of weight loss on phenotypic flexibility.

METHODS

Seventy-two volunteers with overweight and obesity underwent a 12-wk dietary intervention. The participants were randomized to a weight loss group (WLG) with 20% less energy intake or a weight-maintenance group (WMG). At weeks 1 and 12, participants were assessed for body composition by MRI. Concurrently, markers of metabolism and insulin sensitivity were obtained from the analysis of plasma metabolome during 2 different dietary challenges-an oral glucose tolerance test (OGTT) and a mixed-meal tolerance test.

RESULTS

Intended weight loss was achieved in the WLG (-5.6 kg, P < 0.0001) and induced a significant reduction in total and regional adipose tissue as well as ectopic fat in the liver. Amino acid-based markers of insulin action and resistance such as leucine and glutamate were reduced in the postprandial phase of the OGTT in the WLG by 11.5% and 28%, respectively, after body weight reduction. Weight loss correlated with the magnitude of changes in metabolic responses to dietary challenges. Large interindividual variation in metabolic responses to weight loss was observed.

CONCLUSION

Application of dietary challenges increased sensitivity to detect metabolic response to weight loss intervention. Large interindividual variation was observed across a wide range of measurements allowing the identification of distinct responses to the weight loss intervention and mechanistic insight into the metabolic response to weight loss.

Extract of Artemisia dracunculus L. Modulates Osteoblast Proliferation and Mineralization

Thiazolidinediones (TZD) significantly improve insulin sensitivity via action on adipocytes. Unfortunately, TZDs also degrade bone by inhibiting osteoblasts. An extract of Artemisia dracunculus L., termed PMI5011, improves blood glucose and insulin sensitivity via skeletal muscle, rather than fat, and may therefore spare bone. Here, we examine the effects of PMI5011 and an identified active compound within PMI5011 (2',4'-dihydroxy-4-methoxydihydrochalcone, DMC-2) on pre-osteoblasts. We hypothesized that PMI5011 and DMC-2 will not inhibit osteogenesis. To test our hypothesis, MC3T3-E1 cells were induced in osteogenic media with and without PMI5011 or DMC-2. Cell lysates were probed for osteogenic gene expression and protein content and were stained for osteogenic endpoints. Neither compound had an effect on early stain outcomes for alkaline phosphatase or collagen. Contrary to our hypothesis, PMI5011 at 30 µg/mL significantly increases osteogenic gene expression as early as day 1. Further, osteogenic proteins and cell culture mineralization trend higher for PMI5011-treated wells. Treatment with DMC-2 at 1 µg/mL similarly increased osteogenic gene expression and significantly increased mineralization, although protein content did not trend higher. Our data suggest that PMI5011 and DMC-2 have the potential to promote bone health via improved osteoblast maturation and activity.

Dose-response effects of exercise and caloric restriction on visceral adiposity in overweight and obese adults: a systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To determine and compare the dose-response effects of exercise and caloric restriction on visceral adipose tissue in overweight and obese adults, while controlling for the weekly energy deficit induced by the interventions.

METHODS

PubMed, Embase, CINAHL and Web of Science were searched for randomised controlled trials comparing exercise or caloric restriction against eucaloric controls in overweight or obese adults. The primary outcome was the change in visceral fat measured by CT or MRI. Meta-analyses and meta-regressions were performed to determine the overall effect size (ES) and the dose-dependent relationship of exercise and caloric restriction on visceral fat. Heterogeneity, risk of bias and the certainty of evidence were also assessed.

RESULTS

Forty randomised controlled trials involving 2190 participants were included. Overall, exercise (ES -0.28 (-0.37 to -0.19); p<0.001; I2=25%) and caloric restriction (ES -0.53 (-0.71 to -0.35); p<0.001; I2=33%) reduced visceral fat compared with the controls. Exercise demonstrated a dose-response effect of -0.15 ((-0.23 to -0.07); p<0.001) per 1000 calories deficit per week, whereas the effect of caloric restriction was not dose-dependent (ES 0.03 (-0.12 to 0.18); p=0.64). Most of the studies showed a moderate risk of bias.

CONCLUSIONS

These findings support the dose-dependent effects of exercise to reduce visceral fat in overweight and obese adults. Caloric restriction did not demonstrate a dose-response relationship, although this may be attributed to the smaller number of studies available for analysis, compared with exercise studies.

PROSPERO REGISTRATION NUMBER

CRD42020210096.

The Potential of Fasting-Mimicking Diet as a Preventive and Curative Strategy for Alzheimer's Disease

This review examines the potential of fasting-mimicking diets (FMDs) in preventing and treating Alzheimer's disease (AD). FMDs are low-calorie diets that mimic the physiological and metabolic effects of fasting, including the activation of cellular stress response pathways and autophagy. Recent studies have shown that FMDs can reduce amyloid-beta accumulation, tau phosphorylation, and inflammation, as well as improve cognitive function in animal models of AD. Human studies have also reported improvements in AD biomarkers, cognitive functions, and subjective well-being measures following FMDs. However, the optimal duration and frequency of FMDs and their long-term safety and efficacy remain to be determined. Despite these uncertainties, FMDs hold promise as a non-pharmacological approach to AD prevention and treatment, and further research in this area is warranted.

Depot-specific adaption of adipose tissue for different exercise approaches in high-fat diet/streptozocin-induced diabetic mice

Background: Adipose tissue pathology plays a crucial role in the pathogenesis of type 2 diabetes mellitus. Understanding the impact of exercise training on adipose tissue adaptation is of paramount importance in enhancing metabolic health. In this study, we aimed to investigate the effects of various exercise modalities on three distinct adipose tissue depots, namely, interscapular brown adipose tissue (iBAT), subcutaneous white adipose tissue (sWAT), and epididymal white adipose tissue (eWAT), in a murine model of diabetes. Methods: Male C57BL/6J mice received a 12-week high-fat diet and a single injection of streptozotocin, followed by an 8-week exercise intervention. The exercise intervention included swimming, resistance training, aerobic exercise, and high-intensity interval training (HIIT). Results: We found that exercise training reduced body weight and body fat percentage, diminished adipocyte size and increased the expression of mitochondria-related genes (PGC1, COX4, and COX8B) in three adipose tissue depots. The effects of exercise on inflammatory status include a reduction in crown-like structures and the expression of inflammatory factors, mainly in eWAT. Besides, exercise only induces the browning of sWAT, which may be related to the expression of the sympathetic marker tyrosine hydroxylase. Among the four forms of exercise, HIIT was the most effective in reducing body fat percentage, increasing muscle mass and reducing eWAT adipocyte size. The expression of oxidative phosphorylation and thermogenesis-related genes in sWAT and eWAT was highest in the HIIT group. Conclusion: When targeting adipose tissue to improve diabetes, HIIT may offer superior benefits and thus represents a more advantageous choice.

Dietary weight loss-induced improvements in metabolic function are enhanced by exercise in people with obesity and prediabetes

The additional therapeutic effects of regular exercise during a dietary weight loss program in people with obesity and prediabetes are unclear. Here, we show that whole-body (primarily muscle) insulin sensitivity (primary outcome) was 2-fold greater (P = 0.006) after 10% weight loss induced by calorie restriction plus exercise training (Diet+EX; n = 8, 6 women) than 10% weight loss induced by calorie restriction alone (Diet-ONLY; n = 8, 4 women) in participants in two concurrent studies. The greater improvement in insulin sensitivity was accompanied by increased muscle expression of genes involved in mitochondrial biogenesis, energy metabolism and angiogenesis (secondary outcomes) in the Diet+EX group. There were no differences between groups in plasma branched-chain amino acids or markers of inflammation, and both interventions caused similar changes in the gut microbiome. Few adverse events were reported. These results demonstrate that regular exercise during a diet-induced weight loss program has profound additional metabolic benefits in people with obesity and prediabetes.Trial Registration: ClinicalTrials.gov (NCT02706262 and NCT02706288).

Energy restriction or improvements in diet quality: identifying the best pathway for a longer and healthier life

Obesity is a major risk factor for chronic non-communicable diseases (NCDs) and it has increased to epidemic proportions. Unhealthy diet represents a modifiable risk factor for both obesity and NCDs, however, there is no universal dietary intervention to improve obesity-related NCDs and particularly to reduce the risk for major adverse cardiovascular events. Energy restriction (ER) and diet quality changes, with and without ER, have been widely investigated in preclinical and clinical studies, however, the potential underlying mechanisms driving the benefits of those dietary interventions remain largely unclear. ER affects multiple metabolic, physiological, genetic, and cellular adaptation pathways associated with prolonged lifespan, particularly in preclinical models, while these benefits remain to be established in humans. Moreover, the sustainability of ER and its implementation across the different diseases remains challenging. On the other hand, diet quality with improvements, with or without ER, has been associated with more favorable long-term metabolic and cardiovascular outcomes. This narrative review will describe the role of ER and/or diet quality improvements on the risk for NCDs. It will also discuss the potential mechanisms of action underlying the potential beneficial effects of those dietary approaches.

Identification of novel genes associated with exercise and calorie restriction effects in skeletal muscle

Exercise and caloric restriction (CR) significantly increase longevity across a range of species and delay aging-related losses in organ function. Although both interventions enhance skeletal muscle function, the molecular mechanisms underlying these associations are unknown. We sought to identify genes regulated by CR and exercise in muscle, and investigate their relationship with muscle function. To do this, expression profiles of Gene Expression Omnibus datasets obtained from the muscle tissue of calorie-restricted male primates and young men post-exercise were analyzed. There were seven transcripts (ADAMTS1, CPEB4, EGR2, IRS2, NR4A1, PYGO1, and ZBTB43) that were consistently upregulated by both CR and exercise training. We used C2C12 murine myoblasts to investigate the effect of silencing these genes on myogenesis, mitochondrial respiration, autophagy, and insulin signaling, all of which are processes affected by CR and exercise. Our results show that in C2C12 cells, Irs2 and Nr4a1 expression were critical for myogenesis, and five genes (Egr2, Irs2, Nr4a1, Pygo1, and ZBTB43) regulated mitochondrial respiration while having no effect on autophagy. Cpeb4 knockdown increased the expression of genes involved in muscle atrophy and induced myotube atrophy. These findings suggest new resources for studying the mechanisms underlying the beneficial effects of exercise and calorie restriction on skeletal muscle function and lifespan extension.

Comparing the effectiveness of long-term use of daily and weekly glucagon-like peptide-1 receptor agonists treatments in patients with nonalcoholic fatty liver disease and type 2 diabetes mellitus: a network meta-analysis

Objective

In the present network meta-analysis (NMA), we aimed to compare the effectiveness of daily and weekly treatment with glucagon-like peptide-1 receptor agonists for patients with nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM).

Method

We used Stata 17.0 for the NMA. Eligible Randomized controlled trials (RCTs) were searched in PubMed, Cochrane, and Embase databases until December 2022. Two researchers independently screened the available studies. The Cochrane Risk of Bias tool was used to assess the risk of bias in the included studies. We used GRADEprofiler (version3.6) to analyze the evidence certainty. Primary outcomes such as liver fat content (LFC), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels, as well as secondary outcomes such as γ-glutamyltransferase (γGGT) and body weight, were evaluated. Then, each intervention was ranked by the surface under the cumulative ranking curve (SUCRA). As a supplement, we drew forest plots of subgroup using RevMan (version 5.4).

Results

Fourteen RCTs involving 1666 participants were included in the present study. The NMA results showed that exenatide (bid) was the best treatment for improving LFC compared with other agents, liraglutide, dulaglutide, semaglutide (qw) and placebo), and the SUCRA values were 66.8%. Among five interventions (except exenatide (bid) and semaglutide (qw)) evaluated for AST outcome, and six interventions (except exenatide (bid)) evaluated for ALT outcome, semaglutide (qd) was the most effective drug (SUCRA (AST) = 100%, SUCRA (ALT) = 95.6%). The result of LFC in daily group was MD = -3.66, 95% CI [-5.56, -1.76] and in weekly GLP-1RAs group, it was MD = -3.51, 95% CI [-4, -3.02]. As to AST and ALT, the results in daily group versus weekly group were AST: MD = -7.45, 95% CI [-14.57, -0.32] versus MD= -0.58, 95% CI [-3.18, 2.01] and ALT: MD = -11.12, 95% CI [-24.18, 1.95] versus MD = -5.62, 95% CI [-15.25, 4]. The quality of evidence was assessed as moderate or low.

Conclusion

The daily GLP-1RAs may be more effective in primary outcomes. And the daily semaglutide may be the most effective treatment for NAFLD and T2DM among the six interventions.

Metabolic Syndrome and Its Association with Nonalcoholic Steatohepatitis

The relationship between insulin resistance, metabolic syndrome (MetS), and nonalcoholic fatty liver disease (NAFLD) is complicated. Although insulin resistance is almost universal in people with NAFLD and MetS, NAFLD may be present without features of MetS and vice versa. While NAFLD has a strong correlation with cardiometabolic risk factors, these are not intrinsic components of this condition. Taken together, our knowledge gaps call for caution regarding the common assertion that NAFLD is the hepatic manifestation of the MetS, and for defining NAFLD in broad terms as a "metabolic dysfunction" based on a diverse and poorly understood constellation of cardiometabolic features.

Malonylation of Acetyl-CoA carboxylase 1 promotes hepatic steatosis and is attenuated by ketogenic diet in NAFLD

Protein post-translational modifications (PTMs) participate in important bioactive regulatory processes and therefore can help elucidate the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Here, we investigate the involvement of PTMs in ketogenic diet (KD)-improved fatty liver by multi-omics and reveal a core target of lysine malonylation, acetyl-coenzyme A (CoA) carboxylase 1 (ACC1). ACC1 protein levels and Lys1523 malonylation are significantly decreased by KD. A malonylation-mimic mutant of ACC1 increases its enzyme activity and stability to promote hepatic steatosis, whereas the malonylation-null mutant upregulates the ubiquitination degradation of ACC1. A customized Lys1523ACC1 malonylation antibody confirms the increased malonylation of ACC1 in the NAFLD samples. Overall, the lysine malonylation of ACC1 is attenuated by KD in NAFLD and plays an important role in promoting hepatic steatosis. Malonylation is critical for ACC1 activity and stability, highlighting the anti-malonylation effect of ACC1 as a potential strategy for treating NAFLD.

Identification of a weight loss-associated causal eQTL in MTIF3 and the effects of MTIF3 deficiency on human adipocyte function

Genetic variation at the MTIF3 (Mitochondrial Translational Initiation Factor 3) locus has been robustly associated with obesity in humans, but the functional basis behind this association is not known. Here, we applied luciferase reporter assay to map potential functional variants in the haplotype block tagged by rs1885988 and used CRISPR-Cas9 to edit the potential functional variants to confirm the regulatory effects on MTIF3 expression. We further conducted functional studies on MTIF3-deficient differentiated human white adipocyte cell line (hWAs-iCas9), generated through inducible expression of CRISPR-Cas9 combined with delivery of synthetic MTIF3-targeting guide RNA. We demonstrate that rs67785913-centered DNA fragment (in LD with rs1885988, r² > 0.8) enhances transcription in a luciferase reporter assay, and CRISPR-Cas9-edited rs67785913 CTCT cells show significantly higher MTIF3 expression than rs67785913 CT cells. Perturbed MTIF3 expression led to reduced mitochondrial respiration and endogenous fatty acid oxidation, as well as altered expression of mitochondrial DNA-encoded genes and proteins, and disturbed mitochondrial OXPHOS complex assembly. Furthermore, after glucose restriction, the MTIF3 knockout cells retained more triglycerides than control cells. This study demonstrates an adipocyte function-specific role of MTIF3, which originates in the maintenance of mitochondrial function, providing potential explanations for why MTIF3 genetic variation at rs67785913 is associated with body corpulence and response to weight loss interventions.

Effects of Time-Restricted Eating on Nonalcoholic Fatty Liver Disease: The TREATY-FLD Randomized Clinical Trial

IMPORTANCE

The efficacy and safety of time-restricted eating (TRE) on nonalcoholic fatty liver disease (NAFLD) remain uncertain.

OBJECTIVE

To compare the effects of TRE vs daily calorie restriction (DCR) on intrahepatic triglyceride (IHTG) content and metabolic risk factors among patients with obesity and NAFLD.

DESIGN, SETTING, AND PARTICIPANTS

This 12-month randomized clinical trial including participants with obesity and NAFLD was conducted at the Nanfang Hospital in Guangzhou, China, between April 9, 2019, and August 28, 2021.

INTERVENTIONS

Participants with obesity and NAFLD were randomly assigned to TRE (eating only between 8:00 am and 4:00 pm) or DCR (habitual meal timing). All participants were instructed to maintain a diet of 1500 to 1800 kcal/d for men and 1200 to 1500 kcal/d for women for 12 months.

MAIN OUTCOMES AND MEASURES

The primary outcome was change in IHTG content measured by magnetic resonance imaging; secondary outcomes were changes in body weight, waist circumference, body fat, and metabolic risk factors. Intention-to-treat analysis was used.

RESULTS

A total of 88 eligible patients with obesity and NAFLD (mean [SD] age, 32.0 [9.5] years; 49 men [56%]; and mean [SD] body mass index, 32.2 [3.3]) were randomly assigned to the TRE (n = 45) or DCR (n = 43) group. The IHTG content was reduced by 8.3% (95% CI, -10.0% to -6.6%) in the TRE group and 8.1% (95% CI, -9.8% to -6.4%) in the DCR group at the 6-month assessment. The IHTG content was reduced by 6.9% (95% CI, -8.8% to -5.1%) in the TRE group and 7.9% (95% CI, -9.7% to -6.2%) in the DCR group at the 12-month assessment. Changes in IHTG content were comparable between the 2 groups at 6 months (percentage point difference: -0.2; 95% CI, -2.7 to 2.2; P = .86) and 12 months (percentage point difference: 1.0; 95% CI, -1.6 to 3.5; P = .45). In addition, liver stiffness, body weight, and metabolic risk factors were significantly and comparably reduced in both groups.

CONCLUSIONS AND RELEVANCE

Among adults with obesity and NAFLD, TRE did not produce additional benefits for reducing IHTG content, body fat, and metabolic risk factors compared with DCR. These findings support the importance of caloric intake restriction when adhering to a regimen of TRE for the management of NAFLD.

TRIAL REGISTRATION

ClinicalTrials.gov Identifiers: NCT03786523 and NCT04988230.

Aryl hydrocarbon receptor affects circadian-regulated lipolysis through an E-Box-dependent mechanism

An internal circadian clock regulates timing of systemic energy homeostasis. The central clock in the hypothalamic suprachiasmatic nucleus (SCN) directs local clocks in peripheral tissues such as liver, muscle, and adipose tissue to synchronize metabolism with food intake and rest/activity cycles. Aryl hydrocarbon receptor (AhR) interacts with the molecular circadian clockworks. Activation of AhR dampens rhythmic expression of core clock genes, which may lead to metabolic dysfunction. Given the importance of appropriately-timed adipose tissue function to regulation of energy homeostasis, this study focused on mechanisms by which AhR may influence clock-controlled adipose tissue activity. We hypothesized that AhR activation in adipose tissue would impair lipolysis by dampening adipose rhythms, leading to a decreased lipolysis rate during fasting, and subsequently, altered serum glucose concentrations. Levels of clock gene and lipolysis gene transcripts in mouse mesenchymal stem cells (BMSCs) differentiated into mature adipocytes were suppressed by the AhR agonist β-napthoflavone (BNF), in an AhR dependent manner. BNF altered rhythms of core clock gene and lipolysis gene transcripts in C57bl6/J mice. BNF reduced serum free fatty acids, glycerol and liver glycogen. Chromatin immunoprecipitation indicated that BNF increased binding of AhR to E-Box elements in clock gene and lipolysis gene promoters. These data establish a link between AhR activation and impaired lipolysis, specifically by altering adipose tissue rhythmicity. In response to the decreased available energy from impaired lipolysis, the body increases glycogenolysis, thereby degrading more glycogen to provide necessary energy.

Untargeted lipidomics and metagenomics reveal the mechanism of aspirin eugenol ester relieving hyperlipidemia in ApoE-/- mice

Hyperlipidemia is induced by abnormal lipid metabolism, which can cause the occurrence of cardiovascular diseases and lead to grievous injury to health. Studies showed that AEE had a significant therapeutic effect on hyperlipidemia and is likely to be associated with the up-regulation of cholesterol 7-alpha hydroxylase (CYP7A1), the key enzyme for cholesterol conversion to bile acids, but no research confirmed whether the effect of AEE on hyperlipidemia was related to the gut microbiota and liver lipids. At the same time, more and more studies have shown that gut microbiota and lipids are closely related to hyperlipidemia. Hence, in this study, we investigated the effects of AEE on liver lipids through LC-MS-based untargeted lipidomics and the effects of AEE on gut microbiota based on cecal contents metagenomics by Illumina sequencing in HFD-induced hyperlipidemia ApoE-/- mice at the overall level. The results of lipidomics showed that AEE relieved hyperlipidemia by decreasing the concentration of 10 PEs and 12 SMs in the liver and regulating the pathways of glycerophospholipid metabolic pathway, sphingolipid signaling pathway, and NF-kB signaling pathway. The results of metagenomics concluded that AEE treatment changed the composition of gut microbiota and regulated the functions of lipid transport and metabolism, as well as the metabolism of bile acids and secondary bile acids. The results of the joint analysis between lipidomics and metagenomics showed that the abundance of Verrucomicrobia, Verrucomicrobiales, Candidatus_Gastranaerophilales, and Candidatus_Melainabacteria was significantly positively correlated with the concentration of SM (d18:1/18:0) and PE (16:0/18:1) in the process of AEE alleviating hyperlipidemia in mice. In conclusion, these results suggested that the effect of AEE on hyperlipidemia was closely related to the gut microbiota by the change of bile acids and liver lipids.

A Straightforward Method for Adipocyte Size and Count Analysis Using Open-source Software QuPath

Changes in adipose tissue morphology, depicted by cell morphology alterations such as enlargement of fat cells, always accompany over-weight and obesity. The variables related to cell size have been shown to associate with low-grade inflammation of adipose tissue and common obesity-related comorbidities including metabolic syndrome and type 2 diabetes. Quantifying fat cell morphology from images of histological specimens can be tedious. Here, we present a straightforward method for the task using the free open-source software QuPath with its inbuilt tools only. Measurements of human adipose tissue samples with the described protocol showed an excellent correlation with those obtained with ImageJ software with Adipocyte Tools plugin combined with manual correction of misdetections. Intraclass correlation between the two methods was at good to excellent level. The method described here can be applied to considerably large tissue areas, even whole-slide analysis.

Intermittent fasting and exercise therapy abates STZ-induced diabetotoxicity in rats through modulation of adipocytokines hormone, oxidative glucose metabolic, and glycolytic pathway

Diabetes is a global, costly, and growing public health issue. Intermittent fasting (IF) and exercise therapy have been shown to improve insulin sensitivity (IS) in large studies, although the underlying processes are still unknown. The goal of this study, which included both nondiabetic and diabetic rats, was to look at the mechanisms of intermittent fasting and exercise in the management of diabetotoxicity. The effects of starvation and honey on the oral glucose tolerance test, insulin tolerance test, adipocytokines, oxidative glucose metabolic enzymes, glycolytic enzymes, food intake, and body weight in rats with streptozotocin‐induced diabetes were also investigated. In the nondiabetic phase, rats were administered an oral regimen of distilled water (0.5 ml/rat), honey (1 g/kg body weight), and interventions with IF, and starvation for 4 weeks while in the diabetic phase, after STZ or citrate buffer injections, interventions with IF, exercise, starvation, and honey treatment began for 4 weeks. At all OGTT and ITT points, there was a substantial rise in glucose in the STZ group. Adipocytokines hormone, oxidative glucose metabolic enzymes, glycolytic enzymes, and body weight were all affected by STZ when compared to starvation and honey, however, IF and exercise significantly reduced these alterations. In diabetic rats, intermittent fasting and exercise enhanced serum adipocytokines levels. These findings imply that adipokines modulate glycolytic/nonmitochondrial enzymes and glucose metabolic/mitochondrial dehydrogenase to mediate the antidiabetic effects of intermittent fasting and exercise.

Intermittent fasting and exercise therapy abates STZ‐induced diabetotoxicity in rats through modulation of adipocytokines hormone, oxidative glucose metabolic, and glycolytic pathway.

Differential Effects of Amount, Intensity, and Mode of Exercise Training on Insulin Sensitivity and Glucose Homeostasis: A Narrative Review

As type 2 diabetes remains a leading cause of morbidity and mortality, identifying the most appropriate preventive treatment early in the development of disease is an important public health matter. In general, lifestyle interventions incorporating exercise and weight loss via caloric restriction improve cardiometabolic risk by impacting several key markers of insulin sensitivity and glucose homeostasis. However, variations in the effects of specific types of exercise interventions on these markers have led to conflicting results surrounding the optimal amount, intensity, and mode of exercise for optimal effects. Moreover, the addition of weight loss via caloric restriction to exercise interventions appears to differentially impact changes in body composition, metabolism, and insulin sensitivity compared to exercise alone. Determining the optimal amount, intensity, and mode of exercise having the most beneficial impact on glycemic status is both: (1) clinically important to provide guidelines for appropriate exercise prescription; and (2) physiologically important to understand the pathways by which exercise-with and without weight loss-impacts glycemic status to enhance precision lifestyle medicine. Thus, the purposes of this narrative review are to: (1) summarize findings from the three Studies of a Targeted Risk Reduction Intervention through Defined Exercise (STRRIDE) randomized trials regarding the differential effects of exercise amount, intensity, and mode on insulin action and glucose homeostasis markers; and (2) compare the STRRIDE findings to other published dose-response exercise trials in order to piece together the various physiologic pathways by which specific exercise interventions-with or without weight loss-impact glycemic status.

The consumption of micronutrients in relation to calorie intake and risk of insulin resistance

BACKGROUND AND AIMS

Adequate dietary intakes of essential micronutrients are critical to prevent insulin resistance (IR)-related diseases. Even though the excess calorie intake linked with obesity is also associated with such diseases, no previous studies evaluated the importance of meeting the Dietary Reference Intake (DRI) of micronutrients in relation to calorie intake in those at risk for developing IR.

METHODS AND RESULTS

We evaluated the relationship between the ability or failure to meet the DRI of micronutrients in relation to daily calorie intake in 463 childbearing-age women with a higher prevalence of IR. 56-65% women met the DRIs for vitamin B12, vitamin C, thiamine, and riboflavin while only 0%-49% met the DRIs for folate, pyridoxine, niacin, pantothenic acid, total carotene, vitamins A, D and E by consuming an acceptable number of calories. Women who met the DRIs of folate and vitamin C within acceptable daily calorie intakes were 59% and 66% less likely to have higher Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) compared to women who did not.

CONCLUSIONS

Understanding the mechanisms that explain our findings will be of value to address IR-associated with exposure to high calorie/low-micronutrient dense diets consumed by childbearing-age women. Since there is a global recognition that IR has been increasing in adults and children, similar studies of this nature in pregnant women at risk for IR will provide much needed data to assess the burden of such adverse dietary habits in the offspring. Our study approach may form the foundation for such studies.

The Use and Effectiveness of Selected Alternative Markers for Insulin Sensitivity and Secretion Compared with Gold Standard Markers in Dietary Intervention Studies in Individuals without Diabetes: Results of a Systematic Review

Background: The gold-standard techniques for measuring insulin sensitivity and secretion are well established. However, they may be perceived as invasive and expensive for use in dietary intervention studies. Thus, surrogate markers have been proposed as alternative markers for insulin sensitivity and secretion. This systematic review aimed to identify markers of insulin sensitivity and secretion in response to dietary intervention and assess their suitability as surrogates for the gold-standard methodology. Methods: Three databases, PubMed, Scopus, and Cochrane were searched, intervention studies and randomised controlled trials reporting data on dietary intake, a gold standard of analysis of insulin sensitivity (either euglycaemic-hyperinsulinaemic clamp or intravenous glucose tolerance test and secretion (acute insulin response to glucose), as well as surrogate markers for insulin sensitivity (either fasting insulin, area under the curve oral glucose tolerance tests and HOMA-IR) and insulin secretion (disposition index), were selected. Results: We identified thirty-five studies that were eligible for inclusion. We found insufficient evidence to predict insulin sensitivity and secretion with surrogate markers when compared to gold standards in nutritional intervention studies. Conclusions: Future research is needed to investigate if surrogate measures of insulin sensitivity and secretion can be repeatable and reproducible in the same way as gold standards.

Nutritional quality of calorie restricted diets in the CALERIE™ 1 trial

OBJECTIVES

The aim was to determine the nutritional adequacy of calorie restricted (CR) diets during CR interventions up to 12 months.

METHODS

The Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy (CALERIE™) phase 1 trial consisted of 3 single-site studies to test the feasibility and effectiveness of CR in adults without obesity. After baseline assessments, participants who were randomized to a CR intervention received education and training from registered dietitians on how to follow a healthful CR diet. Food diaries were completed at baseline and during the CR interventions (~6, 9, and 12 months) when participants were self-selecting CR diets. Diaries were analyzed for energy, macronutrients, fiber, 11 vitamins, and 9 minerals. Nutritional adequacy was defined by sex- and age-specific Estimated Average Requirement (EAR) or Adequate Intake (AI) criteria for each nutrient. Diet quality was evaluated using the PANDiet diet quality index.

RESULTS

Eighty-eight CR participants (67% women, age 40 ± 9 y, BMI 27.7 ± 1.5 kg/m²) were included in the analysis. Dietary intake of fiber and most vitamins and minerals increased during CR. More than 90% of participants achieved 100% of EAR or AI during CR for 2 of 4 macronutrients (carbohydrate and protein), 6 of 11 vitamins (A, B1, B2, B3, B6, B12), and 6 of 9 minerals assessed (copper, iron, phosphorus, selenium, sodium, zinc). Nutrients for which <90% of participants achieved adequacy included fiber, omega-3 fatty acids, vitamins B5, B9, C, E, and K, and the minerals calcium, magnesium, and potassium. The PANDiet diet quality index improved from 72.9 ± 6.0% at baseline to 75.7 ± 5.2% during CR (p < 0.0001).

CONCLUSION

Long-term, calorie-restricted diets were nutritionally equal or superior to baseline ad libitum diets among adults without obesity. Our results support modest calorie restriction as a safe strategy to promote healthy aging without compromising nutritional adequacy or diet quality.

Physiological Systems in Promoting Frailty

Frailty is a complex syndrome affecting a growing sector of the global population as medical developments have advanced human mortality rates across the world. Our current understanding of frailty is derived from studies conducted in the laboratory as well as the clinic, which have generated largely phenotypic information. Far fewer studies have uncovered biological underpinnings driving the onset and progression of frailty, but the stage is set to advance the field with preclinical and clinical assessment tools, multiomics approaches together with physiological and biochemical methodologies. In this article, we provide comprehensive coverage of topics regarding frailty assessment, preclinical models, interventions, and challenges as well as clinical frameworks and prevalence. We also identify central biological mechanisms that may be at play including mitochondrial dysfunction, epigenetic alterations, and oxidative stress that in turn, affect metabolism, stress responses, and endocrine and neuromuscular systems. We review the role of metabolic syndrome, insulin resistance and visceral obesity, focusing on glucose homeostasis, adenosine monophosphate-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR), and nicotinamide adenine dinucleotide (NAD+ ) as critical players influencing the age-related loss of health. We further focus on how immunometabolic dysfunction associates with oxidative stress in promoting sarcopenia, a key contributor to slowness, weakness, and fatigue. We explore the biological mechanisms involved in stem cell exhaustion that affect regeneration and may contribute to the frailty-associated decline in resilience and adaptation to stress. Together, an overview of the interplay of aging biology with genetic, lifestyle, and environmental factors that contribute to frailty, as well as potential therapeutic targets to lower risk and slow the progression of ongoing disease is covered. © 2022 American Physiological Society. Compr Physiol 12:1-46, 2022.

A comparison of the impact of exercise training with dietary intervention versus dietary intervention alone on insulin resistance and glucose regulation in individual with overweight or obesity: a systemic review and meta-analysis

PURPOSE

Obesity is associated with the development of insulin resistance (IR) and type 2 diabetes for which exercise training (Ex) and dietary interventions (DI) are effective interventions that can improve IR. We therefore performed a systematic meta-analysis to compare the effect of Ex + DI compared with DI on IR and glucose homeostasis.

METHODS

PubMed and Cochrane Library were conducted up to May 2021. Meta-analyses were conducted to compare the effect of Ex + DI compared with DI on fasting glucose and insulin, IR and body weight. Standardized mean differences (SMDs), weighted mean differences (WMD) and 95% confidence intervals (95% CIs) were computed using random or fixed effect models.

RESULTS

Fifty studies involving 2864 participants with overweight or obesity were included in the meta-analysis. Ex + DI caused a larger decrease in fasting glucose (p = 0.001, 62 trials) and IR (p = 0.01, 29 trials) when compared with DI alone. There was no significant evidence, however, for a greater effect of Ex + DI on fasting insulin (p = 0.07, 48 trials) and body weight (p = 0.12, 58 trials), compared with DI alone.

CONCLUSION

Our results suggest that a combination of Ex and DI may be more effective than DI alone at improving IR and fasting glucose in individuals with overweight and obesity.

Exercise training remodels subcutaneous adipose tissue in adults with obesity even without weight loss

Excessive adipose tissue mass underlies much of the metabolic health complications in obesity. Although exercise training is known to improve metabolic health in individuals with obesity, the effects of exercise training without weight loss on adipose tissue structure and metabolic function remain unclear. Thirty-six adults with obesity (body mass index = 33 ± 3 kg · m^-2 ) were assigned to 12 weeks (4 days week^-1 ) of either moderate-intensity continuous training (MICT; 70% maximal heart rate, 45 min; n = 17) or high-intensity interval training (HIIT; 90% maximal heart rate, 10 × 1 min; n = 19), maintaining their body weight throughout. Abdominal subcutaneous adipose tissue (aSAT) biopsy samples were collected once before and twice after training (1 day after last exercise and again 4 days later). Exercise training modified aSAT morphology (i.e. reduced fat cell size, increased collagen type 5a3, both P ≤ 0.05, increased capillary density, P = 0.05) and altered protein abundance of factors that regulate aSAT remodelling (i.e. reduced matrix metallopeptidase 9; P = 0.02; increased angiopoietin-2; P < 0.01). Exercise training also increased protein abundance of factors that regulate lipid metabolism (e.g. hormone sensitive lipase and fatty acid translocase; P ≤ 0.03) and key proteins involved in the mitogen-activated protein kinase pathway when measured the day after the last exercise session. However, most of these exercise-mediated changes were no longer significant 4 days after exercise. Importantly, MICT and HIIT induced remarkably similar adaptations in aSAT. Collectively, even in the absence of weight loss, 12 weeks of exercise training induced changes in aSAT structure, as well as factors that regulate metabolism and the inflammatory signal pathway in adults with obesity. KEY POINTS: Exercise training is well-known to improve metabolic health in obesity, although how exercise modifies the structure and metabolic function of adipose tissue, in the absence of weight loss, remains unclear. We report that both 12 weeks of moderate-intensity continuous training (MICT) and 12 weeks of high-intensity interval training (HIIT) induced modifications in adipose tissue structure and factors that regulate adipose tissue remodelling, metabolism and the inflammatory signal pathway in adults with obesity, even without weight loss (with no meaningful differences between MICT and HIIT). The modest modifications in adipose tissue structure in response to 12 weeks of MICT or HIIT did not lead to changes in the rate of fatty acid release from adipose tissue. These results expand our understanding about the effects of two commonly used exercise training prescriptions (MICT and HIIT) on adipose tissue remodelling that may lead to advanced strategies for improving metabolic health outcomes in adults with obesity.

Satiety Associated with Calorie Restriction and Time-Restricted Feeding: Peripheral Hormones

Calorie restriction (CR) is a common approach to inducing negative energy balance. Recently, time-restricted feeding (TRF), which involves consuming food within specific time windows during a 24-h day, has become popular owing to its relative ease of practice and potential to aid in achieving and maintaining a negative energy balance. TRF can be implemented intentionally with CR, or TRF might induce CR simply because of the time restriction. This review focuses on summarizing our current knowledge on how TRF and continuous CR affect gut peptides that influence satiety. Based on peer-reviewed studies, in response to CR there is an increase in the orexigenic hormone ghrelin and a reduction in fasting leptin and insulin. There is likely a reduction in glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and cholecystokinin (CCK), albeit the evidence for this is weak. After TRF, unlike CR, fasting ghrelin decreased in some TRF studies, whereas it showed no change in several others. Further, a reduction in fasting leptin, insulin, and GLP-1 has been observed. In conclusion, when other determinants of food intake are held equal, the peripheral satiety systems appear to be somewhat similarly affected by CR and TRF with regard to leptin, insulin, and GLP-1. But unlike CR, TRF did not appear to robustly increase ghrelin, suggesting different influences on appetite with a potential decrease of hunger after TRF when compared with CR. However, there are several established and novel gut peptides that have not been measured within the context of CR and TRF, and studies that have evaluated effects of TRF are often short-term, with nonuniform study designs and highly varying temporal eating patterns. More evidence and studies addressing these aspects are needed to draw definitive conclusions.

Fat Cell Size: Measurement Methods, Pathophysiological Origins, and Relationships With Metabolic Dysregulations

The obesity pandemic increasingly causes morbidity and mortality from type 2 diabetes, cardiovascular diseases and many other chronic diseases. Fat cell size (FCS) predicts numerous obesity-related complications such as lipid dysmetabolism, ectopic fat accumulation, insulin resistance, and cardiovascular disorders. Nevertheless, the scarcity of systematic literature reviews on this subject is compounded by the use of different methods by which FCS measurements are determined and reported. In this paper, we provide a systematic review of the current literature on the relationship between adipocyte hypertrophy and obesity-related glucose and lipid dysmetabolism, ectopic fat accumulation, and cardiovascular disorders. We also review the numerous mechanistic origins of adipocyte hypertrophy and its relationship with metabolic dysregulation, including changes in adipogenesis, cell senescence, collagen deposition, systemic inflammation, adipokine secretion, and energy balance. To quantify the effect of different FCS measurement methods, we performed statistical analyses across published data while controlling for body mass index, age, and sex.

The ups and downs of caloric restriction and fasting: from molecular effects to clinical application

Age-associated diseases are rising to pandemic proportions, exposing the need for efficient and low-cost methods to tackle these maladies at symptomatic, behavioral, metabolic, and physiological levels. While nutrition and health are closely intertwined, our limited understanding of how diet precisely influences disease often precludes the medical use of specific dietary interventions. Caloric restriction (CR) has approached clinical application as a powerful, yet simple, dietary modulation that extends both life- and healthspan in model organisms and ameliorates various diseases. However, due to psychological and social-behavioral limitations, CR may be challenging to implement into real life. Thus, CR-mimicking interventions have been developed, including intermittent fasting, time-restricted eating, and macronutrient modulation. Nonetheless, possible side effects of CR and alternatives thereof must be carefully considered. We summarize key concepts and differences in these dietary interventions in humans, discuss their molecular effects, and shed light on advantages and disadvantages.

Assessing Obesity-Related Adipose Tissue Disease (OrAD) to Improve Precision Medicine for Patients Living With Obesity

Obesity is a heterogenous condition that affects the life and health of patients to different degrees and in different ways. Yet, most approaches to treat obesity are not currently prescribed, at least in a systematic manner, based on individual obesity sub-phenotypes or specifically-predicted health risks. Adipose tissue is one of the most evidently affected tissues in obesity. The degree of adipose tissue changes - "adiposopathy", or as we propose to relate to herein as Obesity-related Adipose tissue Disease (OrAD), correspond, at least cross-sectionally, to the extent of obesity-related complications inflicted on an individual patient. This potentially provides an opportunity to better personalize anti-obesity management by utilizing the information that can be retrieved by assessing OrAD. This review article will summarize current knowledge on histopathological OrAD features which, beyond cross-sectional analyses, had been shown to predict future obesity-related endpoints and/or the response to specific anti-obesity interventions. In particular, the review explores adipocyte cell size, adipose tissue inflammation, and fibrosis. Rather than highly-specialized methods, we emphasize standard pathology laboratory approaches to assess OrAD, which are readily-available in most clinical settings. We then discuss how OrAD assessment can be streamlined in the obesity/weight-management clinic. We propose that current studies provide sufficient evidence to inspire concerted efforts to better explore the possibility of predicting obesity related clinical endpoints and response to interventions by histological OrAD assessment, in the quest to improve precision medicine in obesity.