Sarcopenic Obesity, Insulin Resistance, and Their Implications in Cardiovascular and Metabolic Consequences

Therapeutic strategies to modulate gut microbial health: Approaches for sarcopenia management

Sarcopenia is a progressive and generalized loss of skeletal muscle and functions associated with ageing with currently no definitive treatment. Alterations in gut microbial composition have emerged as a significant contributor to the pathophysiology of multiple diseases. Recently, its association with muscle health has pointed to its potential role in mediating sarcopenia. The current review focuses on the association of gut microbiota and mediators of muscle health, connecting the dots between the influence of gut microbiota and their metabolites on biomarkers of sarcopenia. It further delineates the mechanism by which the gut microbiota affects muscle health with progressing age, aiding the formulation of a multi-modal treatment plan involving nutritional supplements and pharmacological interventions along with lifestyle changes compiled in the review. Nutritional supplements containing proteins, vitamin D, omega-3 fatty acids, creatine, curcumin, kefir, and ursolic acid positively impact the gut microbiome. Dietary fibres foster a conducive environment for the growth of beneficial microbes such as Bifidobacterium, Faecalibacterium, Ruminococcus, and Lactobacillus. Probiotics and prebiotics act by protecting against reactive oxygen species (ROS) and inflammatory cytokines. They also increase the production of gut microbiota metabolites like short-chain fatty acids (SCFAs), which aid in improving muscle health. Foods rich in polyphenols are anti-inflammatory and have an antioxidant effect, contributing to a healthier gut. Pharmacological interventions like faecal microbiota transplantation (FMT), non-steroidal anti-inflammatory drugs (NSAIDs), ghrelin mimetics, angiotensin-converting enzyme inhibitors (ACEIs), and butyrate precursors lead to the production of anti-inflammatory fatty acids and regulate appetite, gut motility, and microbial impact on gut health. Further research is warranted to deepen our understanding of the interaction between gut microbiota and muscle health for developing therapeutic strategies for ameliorating sarcopenic muscle loss.

Unveiling a hidden burden: exploring sarcopenia in hospitalized older patients through concordance and cluster analysis

BACKGROUND

Sarcopenia has been shown to be an important condition with the ability to predict negative health outcomes, especially in hospitalized older adults; hence, its accurate identification has an important role in the prognosis of older patients.

AIM

The prevalence of sarcopenia among hospitalized older adults was assessed by employing three distinct diagnostic methods.

METHODS

Older adults who were hospitalized were recruited. Bioelectrical impedance analysis was used to assess muscle mass and body composition. Sarcopenia was diagnosed via the European and Asian criteria and via a modified approach in which the Colombian cutoff points for handgrip and gait speed were used. Finally, a cluster analysis was performed to classify the population.

RESULTS

The prevalence rates of sarcopenia and severe sarcopenia ranged from 7.3 to 31.6%. The agreement between approaches revealed substantial or almost perfect agreement in 30% of the sarcopenia comparisons and 46.6% of the severe sarcopenia comparisons. The cluster analysis defined three different clusters. The first cluster was associated with increased age, BMI and body fat and poorer functional status and muscle. The second cluster was the healthiest, with high functional status and muscle mass. The third cluster had intermediate characteristics.

DISCUSSION

This study highlights the requirements for standardized diagnostic criteria and precise body composition assessment tools in acute geriatric units and highlights the heterogeneity of older adults. Accurate assessment and well-defined diagnostic criteria will facilitate the implementation of appropriate management and interventions.

CONCLUSION

Sarcopenia is highly prevalent in hospitalized older adults, but the adjusted criteria and the inclusion of other parameters must be considered in the assessment.

Comprehensive Analysis of the Association Between Sex Hormones and Body Mass Components Among Men Adults: Results From a Large Population-Based Study

BACKGROUND

As the human body ages, adverse body composition status such as sarcopenia and obesity become obvious phenotypes which can cause numerous health problems. We aimed to comprehensively investigate the association of sex hormones and body mass components in adult men of various age groups.

METHODS

We analysed national representative population data from the US National Health and Nutrition Examination Survey. Generalized linear model regression analyses were used to evaluate the association between sex hormones (total testosterone [TT], bio-available testosterone [BT], sex hormone-binding globulin [SHBG], estradiol [E2] and testosterone to estradiol ratio [T/E ratio]) and body mass components (weight, body mass index (BMI), total lean mass, appendicular lean mass, bone mineral content, total fat and trunk fat). The collection and testing time of blood samples were not fixed and there was no strict fasting, but in subsequent analysis we used statistical methods to minimize the impact of random testing.

RESULTS

After screening for inclusion and exclusion, 3759 male participants aged 20-85 years old were included in this study. Higher levels of TT, SHBG, BT and T/E ratios were significantly associated with higher total lean mass, appendicular lean mass and bone mineral content, while lower weight, BMI, total fat and trunk fat. For E2 levels in men, we found an opposite trend, with higher E2 levels significantly associated with lower total lean mass and appendicular lean mass, and higher weight, BMI, total fat and trunk fat. Notably, in subgroup analysis, the results showed that there were significant interaction effects of age and smoking history in the association between sex hormones and body mass components.

CONCLUSION

Higher TT levels, BT levels, SHBG levels and T/E ratios are associated with lower body weight and improved body composition in young adult men (characterized by higher lean body mass, higher bone density and lower fat mass). The relationship is especially pronounced among relatively young, nonsmoking men.

Single-nucleus transcriptomics reveals subsets of degenerative myonuclei after rotator cuff tear-induced muscle atrophy

Rotator cuff tear (RCT) is the primary cause of shoulder pain and disability and frequently trigger muscle degeneration characterised by muscle atrophy, fatty infiltration and fibrosis. Single-nucleus RNA sequencing (snRNA-seq) was used to reveal the transcriptional changes in the supraspinatus muscle after RCT. Supraspinatus muscles were obtained from patients with habitual shoulder dislocation (n = 3) and RCT (n = 3). In response to the RCT, trajectory analysis showed progression from normal myonuclei to ANKRD1+ myonuclei, which captured atrophy-and fatty infiltration-related regulons (KLF5, KLF10, FOSL1 and BHLHE40). Transcriptomic alterations in fibro/adipogenic progenitors (FAPs) and muscle satellite cells (MuSCs) have also been studied. By predicting cell-cell interactions, we observed communication alterations between myofibers and muscle-resident cells following RCT. Our findings reveal the plasticity of muscle cells in response to RCT and offer valuable insights into the molecular mechanisms and potential therapeutic targets of RCT.

The Association Between Preoperative Sarcopenia and Sarcopenic Obesity and the Occurrence of Postoperative Complications in Patients Undergoing Pancreaticoduodenectomy for Periampullary Malignancies-A Literature Review

BACKGROUND

Sarcopenia and sarcopenic obesity, perceived as a reflection of cancer-induced cachexia, are often diagnosed in patients with periampullary malignancies. The pathophysiology of those conditions is multifactorial regarding the tumor microenvironment, immunological response, and the relationship to surrounding tissues.

METHODS

The PubMed and SCOPUS databases were systematically searched between November 2023 and December 2023. A total of 254 studies were primarily identified. Regarding the inclusion and exclusion criteria, 26 studies were finally included in the review.

RESULTS

Evaluated papers disclosed that sarcopenia was significantly associated with a higher incidence of postoperative complications, including pancreatic fistula (POPF) type B and C, with the odds ratio (OR) ranging from 2.65 (95%CI 1.43-4.93, p = 0.002) to 4.30 (95%CI 1.15-16.01, p < 0.03). Sarcopenic patients also suffered more often from delayed gastric emptying (DGE) with an OR of 6.04 (95%CI 1.13-32.32, p = 0.036). Infectious complications, postoperative hemorrhage, and intra-abdominal abscesses occurred more often in sarcopenic patients. Surgical complications were also noted more frequently when sarcopenic obesity was present. Preoperative nutritional prehabilitation seems to reduce the risk of postoperative complications. However, more prospective studies are needed.

CONCLUSIONS

Sarcopenia and sarcopenic obesity were associated with a higher incidence of multiple postoperative complications, including POPF (type B and C), DGE, hemorrhage, and infectious complications.

The effect of sarcopenic obesity on glycaemic status based on fasting plasma glucose and glycated haemoglobin: A prospective cohort study

AIM

To investigate the effect of sarcopenic obesity on the progression of glycaemic status in middle-aged and older adults without diabetes.

MATERIALS AND METHODS

This research involved 4637 participants without diabetes from the China Health and Retirement Longitudinal Study 2011-2015. Sarcopenic obesity at baseline was evaluated based on the Asian Working Group for Sarcopenia 2019 criteria. According to the American Diabetes Association criteria, we used fasting plasma glucose and glycated haemoglobin to define glycaemic status. Cox proportional hazard models were applied to obtain adjusted hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

The mean age of included participants was 58.98 ± 8.82 years, and 45.35% were men. During 18,497 person-years of follow-up, 1743 (37.59%) cases with glycaemic status progression were identified. Compared with participants without sarcopenia and obesity, participants with sarcopenic obesity, but not sarcopenia only or obesity only, exhibited a higher risk of progression from normoglycaemia to diabetes (HR = 2.11; 95% CI: 1.10-4.04). Moreover, participants with sarcopenic obesity (HR = 1.65; 95% CI: 1.04-2.63), sarcopenia only (HR = 1.78; 95% CI: 1.11-2.86), or obesity only (HR = 2.00; 95% CI: 1.29-3.12) had increased the risk of progression from prediabetes to diabetes.

CONCLUSIONS

The effect of sarcopenic obesity on the progression of glycaemic status based on fasting plasma glucose and glycated haemoglobin may be more pronounced than that of sarcopenia only or obesity only.

Association between Sarcopenic Obesity and Arterial Stiffness in Korean Adults

Objectives: This study examined the association between sarcopenic obesity and arterial stiffness using bioelectrical impedance analysis (BIA). Methods: This retrospective cross-sectional study included 20,601 Korean adults from January 2016 to December 2023. Sarcopenia was defined as height-adjusted appendicular skeletal muscle mass [(ASM/height2) <5.7 in women and <7.0 in men] using BIA. Obesity was defined by body mass index or waist circumference. Arterial stiffness was assessed by measuring brachial-ankle pulse wave velocity (baPWV). The participants were categorized into four groups: normal, sarcopenia, obesity, and sarcopenic obesity. The baPWV values were compared among the four groups to investigate the association between sarcopenic obesity and arterial stiffness using adjusted multivariate analyses. Results: The mean baPWV of the sarcopenic obesity group was higher (p < 0.001) than that of the other groups. The odds ratio for having high baPWV (>1800 cm/s) in the sarcopenic obesity group was 2.40 (95% CI, 1.07-5.38) after adjusting for age, sex, exercise, smoking, heavy alcohol consumption, hypertension, and dyslipidemia. Conclusions: Sarcopenic obesity was independently associated with increased arterial stiffness.

Advancements in sarcopenia diagnosis: from imaging techniques to non-radiation assessments

Sarcopenia is a prevalent condition with significant clinical implications, and it is expected to escalate globally, demanding for effective diagnostic strategies, possibly at an early stage of the disease. Imaging techniques play a pivotal role in comprehensively evaluating sarcopenia, offering insights into both muscle quantity and quality. Among all the imaging techniques currently used for the diagnosis and follow up of sarcopenia, it is possible to distinguish two classes: Rx based techniques, using ionizing radiations, and non-invasive techniques, which are based on the use of safe and low risk diagnostic procedures. Dual-energy x-ray Absorptiometry and Computed Tomography, while widely utilized, entail radiation exposure concerns. Ultrasound imaging offers portability, real-time imaging, and absence of ionizing radiation, making it a promising tool Magnetic Resonance Imaging, particularly T1-weighted and Dixon sequences, provides cross- sectional and high-resolution images and fat-water separation capabilities, facilitating precise sarcopenia quantification. Bioelectrical Impedance Analysis (BIA), a non-invasive technique, estimates body composition, including muscle mass, albeit influenced by hydration status. Standardized protocols, such as those proposed by the Sarcopenia through Ultrasound (SARCUS) Working Group, are imperative for ensuring consistency across assessments. Future research should focus on refining these techniques and harnessing the potential of radiomics and artificial intelligence to enhance diagnostic accuracy and prognostic capabilities in sarcopenia.

Association between body composition and incisional surgical site infection after laparoscopic appendectomy for complicated appendicitis

PURPOSE

Surgical site infection (SSI) is common after laparoscopic appendectomy, resulting in prolonged hospital stay and increased costs. This study examined the relationship between body composition parameters and risk of incisional SSI in patients with complicated appendicitis.

METHODS

We included 411 patients who underwent laparoscopic surgery for complicated appendicitis at a single institution between March 2015 and October 2023. Body composition parameters were derived from preoperative computed tomography (CT). A nomogram was constructed based on the independent predictors of incisional SSI.

RESULTS

Overall, 45 (10.9%) patients developed incisional SSI. Visceral fat area (VFA) was independently associated with risk of incisional SSI (hazard ratio 1.015, 95% confidence interval 1.010-1.020, P < 0.001). A nomogram integrating VFA and two other independent predictors (diabetes and conversion) demonstrated high discriminative (area under the curve = 0.793) and calibration abilities.

CONCLUSIONS

CT-derived VFA could be a valuable predictor of incisional SSI in patients with complicated appendicitis undergoing laparoscopic surgery. A VFA-based nomogram may help in identifying patients at high risk of SSI.

Association between dynapenic obesity and risk of cardiovascular disease: The Hisayama study

BACKGROUND

Dynapenic obesity is a condition characterized by high adiposity levels combined with muscle dysfunction. Although high adiposity and muscle loss/dysfunction are thought to synergistically increase the risk of cardiovascular disease (CVD), few studies have addressed the association between dynapenic and sarcopenic obesity and CVD. We aimed to investigate the association of dynapenic obesity with incident CVD events using the data from a population-based prospective longitudinal study in Japan.

METHODS

A total of 2490 community-dwelling Japanese aged 40-79 years (42.5% males, mean age 57.7 ± 10.6 years) without a history of CVD were followed up for a median of 24 years. Handgrip strength was classified as low, medium, or high by age- and sex-specific tertiles. Body mass index (BMI) levels were categorized as lean (<18.5 kg/m2), normal (18.5-24.9 kg/m2), or obese (≥25.0 kg/m2). Dynapenic obesity was defined as having both low handgrip strength and obesity. The outcomes were defined as the first-ever development of CVD (defined as stroke or coronary heart disease). The hazard ratios (HRs) and their 95% confidence intervals (CIs) for the development of CVD were estimated using a Cox proportional hazards model, in which participants with high handgrip strength and normal BMI were used as a reference group. Mediation analyses used serum high-sensitivity C-reactive protein (hs-CRP) and homeostatic model assessment for insulin resistance (HOMA-IR) as mediators.

RESULTS

During the follow-up period, 482 participants developed CVD events (324 cases of stroke and 209 of coronary heart disease). The multivariable-adjusted risk of CVD increased significantly among participants with dynapenic obesity compared with the reference group (HR 1.49, 95% CI 1.03-2.17). An analysis by age groups showed a further increase in the risk of CVD among participants with dynapenic obesity aged less than 65 years (HR 1.66, 95% CI 1.04-2.65). In mediation analyses for participants aged less than 65 years, serum hs-CRP was shown to be a significant mediator explaining 13.8% of the association between dynapenic obesity and the development of CVD, while HOMA-IR explained 12.2% of this relationship.

CONCLUSIONS

Dynapenic obesity was a significant risk factor for the development of CVD in a general Japanese population. This association was more pronounced among those aged <65 years. Inflammation, and possibly glucose metabolism, might partly mediate this association. Our findings suggest that preventing muscle dysfunction as well as appropriate weight control, especially in middle-age, are important for preventing the development of CVD.

Association between dynapenic abdominal obesity and arthritis among the middle-aged and older Chinese: a longitudinal study

BACKGROUND

This study aimed to assess the longitudinal association between dynapenic abdominal obesity and new-onset arthritis among the middle-aged and older Chinese population.

METHODS

We included 6863 participants from the 2011 and 2015 waves of the China Health and Retirement Longitudinal Study (CHARLS). Dynapenia was defined as handgrip strength < 28 kg for males, and < 18 kg for females. Abdominal obesity was defined as a waist circumference ≥ 90 cm for males and ≥ 85 cm for females. Based on the definitions, all participants were divided into four groups: no dynapenia and no abdominal obesity (ND/NAO), abdominal obesity alone (ND/AO), dynapenia alone (D/NAO), and dynapenia and abdominal obesity (D/AO). The association between dynapenic abdominal obesity and new-onset arthritis was assessed by sex using the Poisson regression models.

RESULTS

After a four-year follow-up, 1272 (18.53%) participants reported new-onset arthritis. Those in the D/AO group had a significantly increased risk of new-onset arthritis compared to those in the ND/NAO group (adjusted relative risk (RR): 1.34, 95% confidence interval (CI): 1.01-1.77). In females, the ND/AO (RR: 1.21, 95% CI: 1.03-1.43) and D/AO (RR: 1.39, 95% CI: 1.01-1.93) groups were associated with a higher risk of arthritis. This significant association was not observed in males.

CONCLUSIONS

Our results indicated that the combined effect of dynapenia and abdominal obesity significantly increased the risk of new-onset arthritis in females, but this association was not observed in males.

Sarcopenia-related changes in serum GLP-1 level affect myogenic differentiation

BACKGROUND

Sarcopenia, a group of muscle-related disorders, leads to the gradual decline and weakening of skeletal muscle over time. Recognizing the pivotal role of gastrointestinal conditions in maintaining metabolic homeostasis within skeletal muscle, we hypothesize that the effectiveness of the myogenic programme is influenced by the levels of gastrointestinal hormones in the bloodstream, and this connection is associated with the onset of sarcopenia.

METHODS

We first categorized 145 individuals from the Emergency Room of Taipei Veterans General Hospital into sarcopenia and non-sarcopenia groups, following the criteria established by the Asian Working Group for Sarcopenia. A thorough examination of specific gastrointestinal hormone levels in plasma was conducted to identify the one most closely associated with sarcopenia. Techniques, including immunofluorescence, western blotting, glucose uptake assays, seahorse real-time cell metabolic analysis, flow cytometry analysis, kinesin-1 activity assays and qPCR analysis, were applied to investigate its impacts and mechanisms on myogenic differentiation.

RESULTS

Individuals in the sarcopenia group exhibited elevated plasma levels of glucagon-like peptide 1 (GLP-1) at 1021.5 ± 313.5 pg/mL, in contrast to non-sarcopenic individuals with levels at 351.1 ± 39.0 pg/mL (P < 0.05). Although it is typical for GLP-1 levels to rise post-meal and subsequently drop naturally, detecting higher GLP-1 levels in starving individuals with sarcopenia raised the possibility of GLP-1 influencing myogenic differentiation in skeletal muscle. Further investigation using a cell model revealed that GLP-1 (1, 10 and 100 ng/mL) dose-dependently suppressed the expression of the myogenic marker, impeding myocyte fusion and the formation of polarized myotubes during differentiation. GLP-1 significantly inhibited the activity of the microtubule motor kinesin-1, interfering with the translocation of glucose transporter 4 (GLUT4) to the cell membrane and the dispersion of mitochondria. These impairments subsequently led to a reduction in glucose uptake to 0.81 ± 0.04 fold (P < 0.01) and mitochondrial adenosine triphosphate (ATP) production from 25.24 ± 1.57 pmol/min to 18.83 ± 1.11 pmol/min (P < 0.05). Continuous exposure to GLP-1, even under insulin induction, attenuated the elevated glucose uptake.

CONCLUSIONS

The elevated GLP-1 levels observed in individuals with sarcopenia are associated with a reduction in myogenic differentiation. The impact of GLP-1 on both the membrane translocation of GLUT4 and the dispersion of mitochondria significantly hinders glucose uptake and the production of mitochondrial ATP necessary for the myogenic programme. These findings point us towards strategies to establish the muscle-gut axis, particularly in the context of sarcopenia. Additionally, these results present the potential of identifying relevant diagnostic biomarkers.

The Oldest of Old Male C57B/6J Mice Are Protected from Sarcopenic Obesity: The Possible Role of Skeletal Muscle Protein Kinase B Expression

The impact of aging on body composition and glucose metabolism is not well established in C57BL/6J mice, despite being a common pre-clinical model for aging and metabolic research. The purpose of this study was to examine the effect of advancing age on body composition, in vivo glucose metabolism, and skeletal muscle AKT expression in young (Y: 4 months old, n = 7), old (O: 17-18 months old, n = 10), and very old (VO: 26-27 month old, n = 9) male C57BL/6J mice. Body composition analysis, assessed by nuclear magnetic resonance, demonstrated O mice had a significantly greater fat mass and body fat percentage when compared to Y and VO mice. Furthermore, VO mice had a significantly greater lean body mass than both O and Y mice. We also found that the VO mice had greater AKT protein levels in skeletal muscle compared to O mice, an observation that explains a portion of the increased lean body mass in VO mice. During glucose tolerance (GT) testing, blood glucose values were significantly lower in the VO mice when compared to the Y and O mice. No age-related differences were observed in insulin tolerance (IT). We also assessed the glucose response to AMPK activation by 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR). The change in blood glucose following AICAR administration was significantly reduced in VO mice compared to Y and AG mice. Our findings indicate that lean body mass and AKT2 protein expression in muscle are significantly increased in VO mice compared to O mice. The increase in AKT2 likely plays a role in the greater lean body mass observed in the oldest of old mice. Finally, despite the increased GT, VO mice appear to be resistant to AMPK-mediated glucose uptake.

Vascular Impairment, Muscle Atrophy, and Cognitive Decline: Critical Age-Related Conditions

The triad of vascular impairment, muscle atrophy, and cognitive decline represents critical age-related conditions that significantly impact health. Vascular impairment disrupts blood flow, precipitating the muscle mass reduction seen in sarcopenia and the decline in neuronal function characteristic of neurodegeneration. Our limited understanding of the intricate relationships within this triad hinders accurate diagnosis and effective treatment strategies. This review analyzes the interrelated mechanisms that contribute to these conditions, with a specific focus on oxidative stress, chronic inflammation, and impaired nutrient delivery. The aim is to understand the common pathways involved and to suggest comprehensive therapeutic approaches. Vascular dysfunctions hinder the circulation of blood and the transportation of nutrients, resulting in sarcopenia characterized by muscle atrophy and weakness. Vascular dysfunction and sarcopenia have a negative impact on physical function and quality of life. Neurodegenerative diseases exhibit comparable pathophysiological mechanisms that affect cognitive and motor functions. Preventive and therapeutic approaches encompass lifestyle adjustments, addressing oxidative stress, inflammation, and integrated therapies that focus on improving vascular and muscular well-being. Better understanding of these links can refine therapeutic strategies and yield better patient outcomes. This study emphasizes the complex interplay between vascular dysfunction, muscle degeneration, and cognitive decline, highlighting the necessity for multidisciplinary treatment approaches. Advances in this domain promise improved diagnostic accuracy, more effective therapeutic options, and enhanced preventive measures, all contributing to a higher quality of life for the elderly population.

Sarcopenic obesity predicts short- and long-term outcomes after neoadjuvant chemotherapy and surgery for gastric cancer

BACKGROUND

Sarcopenic obesity (SO) affects outcomes in various malignancies. However, its clinical significance in patients undergoing neoadjuvant chemotherapy (NAC) for locally advanced gastric cancer (LAGC) remains unclear. This study investigated the impact of pre- and post-NAC SO on postoperative morbidity and survival.

METHODS

Data from 207 patients with LAGC, who underwent NAC followed by radical gastrectomy between January 2010 and October 2019, were reviewed. Skeletal muscle mass and visceral fat area were measured pre- and post-NAC using computed tomography to define sarcopenia and obesity, the coexistence of which was defined as SO.

RESULTS

Among the patients, 52 (25.1%) and 38 (18.4%) developed SO before and after NAC, respectively. Both pre- (34.6%) and post- (47.4%) NAC SO were associated with the highest postoperative morbidity rates; however, only post-NAC SO was an independent risk factor for postoperative morbidity [hazard ratio (HR) = 9.550, 95% confidence interval (CI) = 2.818-32.369; P < .001]. Pre-NAC SO was independently associated with poorer 3-year overall [46.2% vs. 61.3%; HR = 1.258 (95% CI = 1.023-1.547); P = .049] and recurrence-free [39.3% vs. 55.4%; HR 1.285 (95% CI 1.045-1.579); P = .017] survival.

CONCLUSIONS

Pre-NAC SO was an independent prognostic factor in patients with LAGC undergoing NAC; post-NAC SO independently predicted postoperative morbidity.

Dietary recommendations for people with diabetes in special situations: a position statement report by Arabic Association for the Study of Diabetes and metabolism (AASD)

BACKGROUND

Diabetes is a significant global health concern. Regional factors play a crucial role in determining the appropriate diet for patients.

MAIN BODY

The Arabic Association for the Study of Diabetes and Metabolism has developed a position statement that addresses the dietary needs of patients in the context of low income and cultural dietary habits. This statement aims to explore the most suitable diet for Middle East and North Africa (MENA) region and provide guidance for physicians to overcome barriers in optimal care. While most dietary guidelines focus on uncomplicated diabetes, it's essential to recognize that diabetes often coexists with other common diseases in our region.

CONCLUSION

International guidelines cannot be directly applied to the Egypt and Arab countries due to cultural and dietary differences. Our position statement shares valuable insights into managing diabetes in special situations and diverse clinical settings within this region. These recommendations are flexible, considering personal, cultural, and traditional differences.

Dietary intake by patients taking GLP-1 and dual GIP/GLP-1 receptor agonists: A narrative review and discussion of research needs

Background

Obesity and type 2 diabetes mellitus (T2DM) are increasingly common in the United States and worldwide. Because both conditions are associated with serious health consequences, weight reduction is recommended by professional medical and nutrition societies to improve outcomes. Due to the striking efficacy of glucagon-like peptide receptor agonists (GLP-1RAs) and dual mechanism glucose-dependent insulinotropic polypeptide/glucagon-like peptide receptor agonists (GIP/GLP-1RAs) for weight reduction and glycemic control, there is increased utilization for patients with obesity and/or T2DM. Yet, the impact of these medications on dietary intake is less understood.

Methods

This narrative literature review summarizes clinical studies quantifying and characterizing dietary intake in people with obesity and/or T2DM using GLP-1 or GIP/GLP-1 RAs.

Results

Though data from these studies reveal that total caloric intake was reduced by 16-39 %, few studies evaluated the actual composition of the diet.

Conclusions

Further research is needed to understand the unique nutritional needs of adults on GLP-1 or dual GIP/GLP-1RAs and to support the development of nutritional guidelines for these individuals.

Sex difference in the association between creatinine-to-cystatin C ratio and metabolic syndrome among Chinese adults

Background

Metabolic syndrome (MetS), characterized by central obesity, insulin resistance, dyslipidemia, and hypertension, affects 20-25% of the global population. The creatinine-to-cystatin C ratio (CCR) is an indicator of skeletal muscle mass. While CCR may play a role in MetS development, sex differences in these associations are not fully understood. Therefore, this study aimed to investigate how CCR levels are associated with MetS in a Chinese adult population, focusing on possible sex disparities.

Method

We conducted a retrospective cross-sectional analysis of 9,376 adults from Xiamen Chang Gung Hospital between 2014 to 2016. We examined the relationship between CCR and MetS, adjusting for cardiometabolic risk factors.

Results

The prevalence of MetS was 24.7% in males and 18.0% in females. Interestingly, we observed significant sex differences in the association between CCR quartiles and MetS. Females in the lowest CCR quartile had a significantly higher risk of MetS (odds ratio=1.84). Receiver operating characteristic curve analysis revealed acceptable diagnostic power of CCR for MetS in females (area under the curve=0.65) but not in males.

Conclusion

Our findings suggest that CCR is an independent risk factor for MetS in females, highlighting the importance of sex-specific assessments when evaluating MetS risk.

Research Progress on the Effect and Mechanism of Exercise Intervention on Sarcopenia Obesity

With the increasingly severe situation of obesity and population aging, there is growing concern about sarcopenia obesity (SO). SO refers to the coexistence of obesity and sarcopenia, which imposes a heavier burden on individuals and society compared to obesity or sarcopenia alone. Therefore, comprehending the pathogenesis of SO and implementing effective clinical interventions are vital for its prevention and treatment. This review uses a comprehensive literature search and analysis of PubMed, Web of Science, and CNKI databases, with search terms including "Sarcopenic obesity", "exercise", "cytokines", "inflammation", "mitochondrial quality control", and "microRNA", covering relevant studies published up to July 2024. The results indicate that the pathogenesis of SO is complex, involving mechanisms like age-related changes in body composition, hormonal alterations, inflammation, mitochondrial dysfunction, and genetic and epigenetic factors. Regarding exercise interventions for SO, aerobic exercise can reduce fat mass, resistance exercise can increase skeletal muscle mass and strength, and combined exercise can achieve both, making it the optimal intervention for SO. The potential mechanisms by which exercise may prevent and treat SO include regulating cytokine secretion, inhibiting inflammatory pathways, improving mitochondrial quality, and mediating microRNA expression. This review emphasizes the effectiveness of exercise interventions in mitigating sarcopenic obesity through comprehensive analysis of its multifactorial pathogenesis and the mechanistic insights into exercise's therapeutic effects. Understanding these mechanisms informs targeted therapeutic strategies aimed at alleviating the societal and individual burdens associated with SO.

Associations of muscle mass, strength, and quality with diabetes and the mediating role of inflammation in two National surveys from China and the United states

AIMS

The evidence for joint and independent associations of low muscle mass and low muscle strength with diabetes is limited and mixed. The study aimed to determine the associations of muscle parameters (muscle mass, strength, quality, and sarcopenia) and sarcopenia obesity with diabetes, and the previously unstudied mediating effect of inflammation.

MATERIALS AND METHODS

A total of 13,420 adults from the 2023 China National Health Survey (CNHS) and 5,380 adults from the 2011-2014 National Health and Nutrition Examination Survey (NHANES) were included in this study. Muscle mass was determined using bioelectrical impedance analysis (BIA) in the CNHS, and whole-body dual X-ray absorptiometry (DXA) in the NHANES. Muscle strength was assessed using digital hand dynamometer. Multivariate logistic regression models were used to evaluate the associations of muscle parameters and sarcopenia obesity with diabetes. Inflammatory status was assessed using blood cell counts and two systemic inflammation indices (platelet-to-lymphocyte ratio (PLR) and system inflammation response index (SIRI)). Mediation analysis was conducted to examine inflammation's role in these associations.

RESULTS

Low muscle mass and strength were independently related to diabetes. Low muscle quality was associated with elevated diabetes risk. Sarcopenia has a stronger association with diabetes compared to low muscle strength alone or mass alone (CNHS, odds ratio (OR) = 1.93, 95 % confidence interval (CI):1.64-2.27; NHANES, OR = 3.80, 95 %CI:2.58-5.58). Participants with sarcopenia obesity exhibit a higher risk of diabetes than those with obesity or sarcopenia alone (CNHS, OR = 2.21, 95 %CI:1.72-2.84; NHANES, OR = 6.06, 95 %CI:3.64-10.08). Associations between muscle parameters and diabetes were partially mediated by inflammation (mediation proportion: 1.99 %-36.64 %, P < 0.05).

CONCLUSION

Low muscle mass and muscle strength are independently or jointly associated with diabetes, and inflammation might be a potential mechanism underlying this association. Furthermore, the synergistic effects of sarcopenia and obesity could significantly increase diabetes risk.

Sarcopenic obesity and pre-sarcopenia contribute to frailty in community-dwelling Italian older people: data from the FRASNET study

BACKGROUND

The ageing process is characterized by a change of body composition with an increase of fat mass and a reduction of muscle mass. Above a certain threshold these alterations configure a condition named sarcopenic obesity (SO). SO is associated with physical frailty in Asian and Brazilian populations. SO impacts on physical frailty in other ethnic groups but its influence on general frailty which is multidimensional and includes cognitive, social and physical factors, remain insufficiently explored in the Italian population.

METHODS

Frailty was measured in community dwelling Italian older adults enrolled in the FRASNET study with the frailty index (FI). The FI quantifies frailty as the ratio of the number of present health deficits to the total number of health deficits considered. Regression analyses were performed to assess the association between body composition categories and frailty. Classification and regression tree models were run to evaluate the frailty predictors.

RESULTS

One Thousand One Hundred Fourteen participants of the FRASNET study were included in the present analysis. The sample was composed for the 60.5% by females and its median age was 72 years. The median FI score was 0.11 (IQR 0.07-0.20); 234 individuals (21%) were frail (FI ≥ 0.25). SO (B 0.074, 95% C.I. 0.05-0.1, p < 0.001) and pre-sarcopenia (without obesity B 0.03, 95% C.I, 0.007-0.044, p < 0.001, with obesity B 0.11, 95% C.I. 0.05-0.16, p < 0.001) were associated with frailty. Fat mass percentage predicted frailty in people aged 65-70 years whereas, muscle strength predicted general frailty in people aged 70-81 years.

CONCLUSION

Pre-sarcopenia and SO represent potentially treatable predictors of frailty.

Muscle Organoid and Assembloid Systems

Skeletal muscle is one of the most complex and largest tissues that perform important processes in the body, including performing voluntary movements and maintaining body temperature. Disruption of muscle homeostasis results in the development of several disorders, including diabetes and sarcopenia. To study the developmental and regenerative dynamics of skeletal muscle and the mechanism behind muscle diseases, it is important to model skeletal muscle and diseases in vitro. Since skeletal muscle has a complex structure and interaction with other tissues and cells that are required to perform their function, conventional 2D cultures are not sufficient to model the skeletal muscle with their interactions. Advances in the field of organoids and assembloids will enable the establishment of more complex and realistic tissue or disease models which cannot be fully recapitulated in conventional 2D culture systems for use in several areas, including disease research, regenerative, and tissue biology. To overcome these limitations, 3D organoid systems and assembloid systems are promising because of their success in recapitulating the complex structural organization, function, and cellular interactions of skeletal muscle.

The obesity-related mutation gene on nonalcoholic fatty liver disease

The prevalence of overweight and obesity is increasing, leading to metabolic-associated fatty liver disease (MAFLD) characterized by excessive accumulation of liver fat and a risk of developing hepatocellular carcinoma (HCC). The driver gene mutations may play the roles of passengers that occur in single 'hotspots' and can promote tumorigenesis from benign to malignant lesions. We investigated the impact of high body weight and BMI on HCC survival using The Cancer Genome Atlas Liver Hepatocellular Carcinoma (TCGA-LIHC) dataset. To explore the effects of obesity-related gene mutations on HCC, we collected driver mutation genes in 34 TCGA patients with BMI ≥ 27 and 23 TCGA patients with BMI < 27. The digital PCR performing the PBMC samples for the variant rate by clinical cohort of 96 NAFLD patients. Our analysis showed that obesity leads to significantly worse survival outcomes in HCC. Using cbioportal, we identified 414 driver mutation genes in patients with obesity and 127 driver mutation genes in non-obese patients. Functional analysis showed that obese-related genes significantly enriched the regulated lipid and insulin pathways in HCC. The insulin secretion pathway in patients with obesity HCC-specific survival identified ABCC8 and PRKCB as significant genes (p < 0.001). It revealed significant differences in gene mutation and gene expression profiles compared to non-obese patients. The digital PCR test ABCC8 variants were detected in PBMC samples and caused a 14.5% variant rate, significantly higher than that of non-obese NAFLD patients. The study findings showed that the gene ABCC8 was a patient with the obesity-related gene in NAFLD, which provides the probability that ABCC8 mutation contributes to the pre-cancer lesion biomarker for HCC.

New specific skeletal muscle mass index cut-offs for the assessment of sarcopenia in patients with severe obesity

Introduction

Bioelectrical impedance analysis (BIA) is the most used tool in clinical practice to evaluate body composition in patients with obesity. The skeletal muscle index (SMI) defined by BIA has been proposed for the identification of sarcopenia, but there are currently no univocal cutoffs for this condition. In this study, we aimed: 1) to determine the prevalence of sarcopenia in patients with severe obesity using the current cutoffs of SMI; 2) to define new specific cutoffs; 3) to validate the new cutoffs; and 4) to re-determine the prevalence of sarcopenia.

Methods

A total of 300 patients, 74% women and 26% men (mean age = 42.6 ±; 9 years), with morbid obesity (mean BMI = 46.7 ±; 6.5 kg/m2) followed by the Unit of Endocrinology from January 2014 to December 2020 were retrospectively evaluated. SMI was calculated as the skeletal muscle mass normalized for squared height through the BIA equation by Janssen et al.

Results

The prevalence of sarcopenic obesity calculated using the cutoff points reported by De Rosa et al. (7.3 kg/h2 for women and 9.5 kg/h2 for men) was 2.3%. The prevalence of sarcopenia was calculated using the new cutoffs: with the cutoff obtained from the standard deviation method (8.2 kg/h2 for women and 10.2 kg/h2 for men), a prevalence of 14.7% was observed, whereas the prevalence reached 47.6% when using the cutoff calculated through the K-means unsupervised cluster (9.2 kg/h2 for women and 11.3 kg/h2 for men). The new cutoffs were validated with a second sample consisting of 300 patients with morbid obesity (BMI = 44.9 ±; 6.7 kg/m2): the rate of sarcopenic patients was still higher than that observed in the training cohort (56%). After the matching procedure (by BMI and age), the rates of sarcopenic patients were similar in both groups (50.2% in the validation group and 53% in the training group, p = 0.6).

Conclusion

The new cutoffs calculated with cluster analysis could better identify sarcopenia in morbidly obese patients. However, further studies are needed to validate these cutoffs in different patient cohorts.

Associations Between Life's Essential 8 and Insulin Resistance Among Nondiabetic Adults

BACKGROUND

Insulin resistance (IR) is closely linked to cardiometabolic diseases. Preventing and improving IR in nondiabetic populations is critically important. We aimed to investigate the relationship between Life's Essential 8 (LE8), the latest tool from the American Heart Association quantifying cardiovascular health, and IR among nondiabetic populations in the United States.

METHODS AND RESULTS

This cross-sectional study used data on 11 246 nondiabetic adults aged ≥20 years from the 2005 to 2018 the National Health and Nutrition Examination Survey. The LE8 score was classified into 2 subscale scores: health factor score and health behavior score. IR was measured by homeostasis model assessment of insulin resistance (HOMA-IR). Weighted logistic and linear regression models analyzed associations among the LE8 score, health behavior score, health factor score, and IR. Restricted cubic spline models assessed dose-response relationships. Adjusted subgroup analyses and inverse probability of treatment weighting method also evaluated the LE8-IR relationship. Of the 11 246 participants, 4860 (43.2%) had IR. The mean LE8 score was 70.07 (95% CI, 69.57-70.58). In fully adjusted models, higher LE8 scores were associated with lower IR odds (odds ratio per 10-unit increase, 0.57 [95% CI, 0.54-0.61]). Nonlinear LE8-IR dose-response was observed. Similar patterns were seen for health behavior and health factor subscores, with stronger IR correlations for health factors. The inverse LE8-IR association was significantly more pronounced among White participants and those with higher education, higher income, and without hypertension, cardiovascular disease, or chronic kidney disease. Significant negative LE8-IR associations persisted after inverse probability of treatment weighting.

CONCLUSIONS

LE8 and subscale scores are negatively associated with IR in a nonlinear relationship. Promoting optimal cardiovascular health adherence may improve IR in nondiabetic populations.

The role of sarcopenic obesity for the prediction of prognosis of patients with gastrointestinal cancer

BACKGROUND

Sarcopenic obesity (SO) in patients with gastrointestinal cancer is associated with a poor prognosis. We aimed to investigate the prognostic impact of SO in patients with gastrointestinal cancer, as well as the diagnostic cut-off value of SO in patients with gastrointestinal cancer among Chinese population.

METHODS

We conducted a consecutive cohort study. Between January 2017 and January 2019, 289 patients diagnosed with gastrointestinal cancer were included in our study. Skeletal muscle area, total fat area, and subcutaneous fat area were measured by CT scan. All patients were followed up for 5 years. Receiver operating characteristic curves (ROC) were adopted to determine the cut-off values of visceral fat obesity for the prediction of sarcopenia. Based on the cut-off values, patients with sarcopenia combined with visceral fat obesity were divided into the SO group, and the others were divided into the non-sarcopenic obesity (NSO) group. Kaplan-Meier curves and univariate and multivariate Cox proportional hazard models were employed to explore the associations of body composition profiles with 5-year overall survival and disease-specific survival.

RESULTS

Obtained from Youden's Index for ROC for the prediction of 5-year survival, skeletal muscle mass index (SMI) ≤40.02 cm2/m2 with VFA ≥ 126.30 cm2 in men and SMI ≤32.05 cm2/m2 with VFA ≥72.42 cm2 in women indicate a risk of poor prognosis in patients diagnosed with gastrointestinal cancer. Patients with SO had poorer 5-year overall survival (OS) than patients with NSO (6.74% vs. 82.84%, p < 0.001), and poorer 5-year DFS (6.74% vs. 81.82%, p < 0.001). In multivariate analysis, we found that the long-term mortality risk was approximately 13-fold higher among patients in the SO group compared to those with no conditions.

CONCLUSIONS

Preoperative assessment of SO is useful not only for monitoring nutritional status but also for predicting 5-year OS in gastrointestinal cancer patients.

Sarcopenia and metabolic dysfunction associated steatotic liver disease: Time to address both

Sarcopenia and metabolic dysfunction associated steatotic liver disease (MASLD) are closely intertwined. Sarcopenia, traditionally a disease of the older adult and chronic disease population, has been closely studied as one of the pathophysiologic conditions at play in the development of MASLD. They share similar risk factors of insulin resistance and physical inactivity. Given similar pathophysiology along the liver-muscle axis, sarcopenia has been studied as a risk factor for MASLD, and vice versa. Current research suggests a bidirectional relationship. Given the chronicity of MASLD as a chronic inflammatory liver disease, it can break down muscle mass and lead to sarcopenia, while sarcopenia promotes intramuscular lipid accumulation that releases cytokines that can aggravate inflammation in the liver. However, for the longest time, a lack of consensus definition for MASLD and sarcopenia made it difficult to study their relationship and outcomes. A recent nomenclature update to diagnosing MASLD has made it easier for researchers to identify cohorts for study. However, no gold standard technique to measure muscle mass or consensus sarcopenia definition has been identified yet. Future studies are needed to reach a consensus and reduce diagnostic variation. With similar pathophysiology and shared risk factors between the two diseases, future research may also identify potential therapeutic targets along the liver-muscle axis that would benefit both sarcopenia and MASLD in order to maximize their outcomes.

Importance of Assessing Sarcopenia in Patients with Type 2 Diabetes Mellitus Based on Body Fat Percentage Measured by Dual-Energy X-Ray Absorptiometry in Different Genders

Background

Growing evidence indicates that there is a close relationship between type 2 diabetes mellitus (T2DM) and sarcopenia, and T2DM patients are often accompanied by obesity. However, research exploring the connection between body fat percentage (BFP) and sarcopenia is currently limited.

Methods

This was a cross-sectional study that included 676 patients with T2DM over 50 years old. The appendicular skeletal muscle mass index (ASMI), handgrip strength, and 5-time chair stand test (5-TCST) were measured, and sarcopenia was diagnosed according to the Asian Working Group on Sarcopenia (AWGS). Spearman's coefficient was used to evaluate the correlation of BFP and body mass index (BMI) with the diagnostic elements of sarcopenia, and BFP and other relevant covariates were included in the binary logistic regression model. The subgroup performed an interaction test for statistically significant population baseline information.

Results

The prevalence of sarcopenia was 18.0% in males and 11.6% in females. Spearman correlation analysis showed that BFP was positively correlated with ASMI in women (R=0.107, P=0.029), but not in men. BFP was negatively correlated with grip strength (male: R= -0.187, P=0.003; female: R=-0.108, P=0.029). There was a positive correlation between BFP and 5-TCST (male: R=0.199, P=0.001; female: R=0.144, P=0.003). After adjusting for confounding factors, BFP was an independent risk factor for sarcopenia (men, OR: 1.33, 95% CI: 1.15-1.54; women, OR: 1.26, 95% CI: 1.13-1.41). This correlation was generally consistent, as demonstrated in further subgroup analyses.

Conclusion

High BFP was significantly associated with sarcopenia risk, and this association was independent of gender, age, and BMI.

Unraveling the enigma of sarcopenia and sarcopenic obesity in Indian adults with type 2 diabetes - a comparative cross-sectional study

BACKGROUND

Sarcopenia and sarcopenic obesity are growing concerns associated with increasing diabetes incidence, but data from Indian diabetic cohorts are limited. This study examined the prevalence and clinical factors associated with sarcopenia and sarcopenic obesity.

METHODS

In this cross-sectional study, 750 participants aged 35-70 years were recruited by systematic stratification and a fixed quota sampling technique from medical camps and categorized into diabetic (n = 250), nondiabetic (n = 250), and obese nondiabetic (n = 250) groups. The assessments included questionnaires, muscle mass estimation by bioimpedance analysis, and blood tests. Sarcopenia was defined using the Asian Working Group consensus, and sarcopenic obesity was defined as sarcopenia with a BMI ≥ 25 kg/m2. Logistic regression was used to analyze risk factors.

RESULTS

Sarcopenia affected 60% of diabetic patients, 28% of nondiabetic patients, and 38% of nonobese nondiabetic patients (p < 0.001). The prevalence of sarcopenic obesity was 40%, 11%, and 30%, respectively (p < 0.001). Diabetes was associated with 2.3-fold greater odds (95% CI 1.1-4.7) of sarcopenia and 2.4-fold greater odds (1.1-5.0) of sarcopenic obesity after adjustment. A duration greater than 10 years, uncontrolled diabetes, age greater than 65 years, low physical activity, hypertension, and dyslipidemia also independently increased the odds.

CONCLUSION

Indian adults with type 2 diabetes have a high burden of sarcopenia and sarcopenic obesity. Early optimization of diabetes care and lifestyle changes are vital for preserving muscle health.

Clinical characteristics and treatment compounds of obesity-related kidney injury

Disorders in energy homeostasis can lead to various metabolic diseases, particularly obesity. The obesity epidemic has led to an increased incidence of obesity-related nephropathy (ORN), a distinct entity characterized by proteinuria, glomerulomegaly, progressive glomerulosclerosis, and renal function decline. Obesity and its associated renal damage are common in clinical practice, and their incidence is increasing and attracting great attention. There is a great need to identify safe and effective therapeutic modalities, and therapeutics using chemical compounds and natural products are receiving increasing attention. However, the summary is lacking about the specific effects and mechanisms of action of compounds in the treatment of ORN. In this review, we summarize the important clinical features and compound treatment strategies for obesity and obesity-induced kidney injury. We also summarize the pathologic and clinical features of ORN as well as its pathogenesis and potential therapeutics targeting renal inflammation, oxidative stress, insulin resistance, fibrosis, kidney lipid accumulation, and dysregulated autophagy. In addition, detailed information on natural and synthetic compounds used for the treatment of obesity-related kidney disease is summarized. The synthesis of detailed information aims to contribute to a deeper understanding of the clinical treatment modalities for obesity-related kidney diseases, fostering the anticipation of novel insights in this domain.

The diagnostic agreement of sarcopenic obesity with different definitions in Chinese community-dwelling middle-aged and older adults

Background

In 2022, the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO) launched a consensus on the diagnostic methods for sarcopenic obesity (SO). The study aimed to identify the prevalence and diagnostic agreement of SO using different diagnostic methods in a cohort of subjects from West China aged at least 50 years old.

Methods

A large multi-ethnic sample of 4,155 participants from the West China Health and Aging Trend (WCHAT) study was analyzed. SO was defined according to the newly published consensus of the ESPEN/EASO. Furthermore, SO was diagnosed as a combination of sarcopenia and obesity. The criteria established by the Asian Working Group for Sarcopenia 2019 (AWGS2019) were used to define sarcopenia. Obesity was defined by four widely used indicators: percent of body fat (PBF), visceral fat area (VFA), waist circumference (WC), and body mass index (BMI). Cohen's kappa was used to analyze the diagnostic agreement of the above five diagnostic methods.

Results

A total of 4,155 participants were part of the study, including 1,499 men (63.76 ± 8.23 years) and 2,656 women (61.61 ± 8.20 years). The prevalence of SO was 0.63-7.22% with different diagnostic methods. The diagnosis agreement of five diagnostic methods was poor-to-good (κ: 0.06-0.67). The consensus by the ESPEN/EASO had the poorest agreement with other methods (κ: 0.06-0.32). AWGS+VFA had the best agreement with AWGS+WC (κ = 0.67), and consensus by the ESPEN/EASO had the best agreement with AWGS+ PBF (κ = 0.32).

Conclusion

The prevalence and diagnostic agreement of SO varies considerably between different diagnostic methods. AWGS+WC has the highest diagnostic rate in the diagnosis of SO, whereas AWGS+BMI has the lowest. AWGS+VFA has a relatively good diagnostic agreement with other diagnostic methods, while the consensus of the ESPEN/EASO has a poor diagnostic agreement. AWGS+PBF may be suitable for the alternative diagnosis of the 2022 ESPEN/EASO.

Pathogenesis of MASLD and MASH - role of insulin resistance and lipotoxicity

BACKGROUND

Insulin resistance and lipotoxicity are extremely interconnected but fundamental in setting the stage for the development of MASLD/MASH.

AIM/METHODS

A comprehensive literature search was performed and key themes were synthesised to provide insight into the underlying molecular mechanisms of insulin resistance and lipotoxicity in the liver, muscle, pancreas and adipose tissue and how organ cross-talk is fundamental to driving disease pathogenesis.

RESULTS

Classical thinking postulates that excess FFA load exceeds the storage capacity of adipose tissue, which is predicated upon both genetic and environmental factors. This results in insulin resistance and compensatory hyperinsulinaemia by pancreatic beta cells to overcome target organ insulin resistance. As adipocyte dysfunction worsens, not only are excess FFA delivered to other organs, including skeletal muscle, pancreas and liver but a pro-inflammatory milieu is established with increases in IL-6, TNF-α and changes in adipokine levels (increased leptin and decreased adiponectin). With increased intramuscular lipid accumulation, lipotoxic species decrease insulin signalling, reduce glucose uptake by downregulation of GLUT4 and decrease glycogen synthesis. With this additional reduced capacity, hyperglycaemia is further exacerbated and increased FFA are delivered to the liver. The liver has the largest capacity to oxidise fat and to adapt to these stressors and, therefore, has become the last line of defence for excess lipid storage and utilisation, the capacity of which may be impacted by genetic and environmental factors. However, when the liver can no longer keep up with increasing FFA delivery and DNL, lipotoxic species accumulate with ensuing mitochondrial dysfunction, increased ER stress, oxidant stress and inflammasome activation, all of which drive hepatocyte injury and apoptosis. The resulting wound healing response, marked by stellate cell activation, drives collagen accumulation, progressive fibrosis, and, ultimately, end organ failure and death. This vicious cycle and complex interplay between insulin resistance, hyperinsulinaemia, lipotoxicity and multi-directional cross-talk among different target organs are critical drivers of MASLD/MASH.

CONCLUSIONS

Targeting tissue-specific insulin resistance and hyperinsulinaemia while decreasing FFA load (lipotoxicity) through dietary and lifestyle changes remain the best upstream interventions.

Sarcopenia: A dive into metabolism to promote a multimodal, preventive, and regenerative approach

Sarcopenia, the age-related loss of skeletal muscle mass and function, poses a significant challenge in the field of geriatrics and gerontology, impacting the health and independence of older adults. Understanding and addressing sarcopenia is crucial for optimizing clinical outcomes and enhancing the quality of life along with aging. By synthesizing current research findings and theoretical frameworks, this review elucidates the multifaceted mechanisms underlying sarcopenia, mainly focusing on energy balance and metabolic processes. Furthermore, the manuscript explores the implications of sarcopenia on overall health outcomes, functional decline, and quality of life in older individuals. The study concludes with a perspective on the role of preventive and regenerative medicine in sarcopenia, where the two main lifestyle pillars (exercise and diet) represent key factors.

The causal relationship between sarcopenia-related traits and ischemic stroke: Insights from univariable and multivariable Mendelian randomization analyses

AIMS

The causal relationship between sarcopenia-related traits and ischemic stroke (IS) remains poorly understood. This study aimed to explore the causal impact of sarcopenia-related traits on IS and to identify key mediators of this association.

METHODS

We conducted univariable, multivariable two-sample, and two-step Mendelian randomization (MR) analyses using genome-wide association study (GWAS) data. This included data for appendicular lean mass (ALM), hand grip strength (HGS), and usual walking pace (UWP) from the UK Biobank, and IS data from the MEGASTROKE consortium. Additionally, 21 candidate mediators were analyzed based on their respective GWAS data sets.

RESULTS

Each 1-SD increase in genetically proxied ALM was associated with a 7.5% reduction in the risk of IS (95% CI: 0.879-0.974), and this correlation remained after controlling for levels of physical activity and adiposity-related indices. Two-step MR identified that six mediators partially mediated the protective effect of higher ALM on IS, with the most significant being coronary heart disease (CHD, mediating proportion: 39.94%), followed by systolic blood pressure (36.51%), hypertension (23.87%), diastolic blood pressure (15.39%), type-2 diabetes mellitus (T2DM, 12.71%), and low-density lipoprotein cholesterol (7.97%).

CONCLUSION

Our study revealed a causal protective effect of higher ALM on IS, independent of physical activity and adiposity-related indices. Moreover, we found that higher ALM could reduce susceptibility to IS partially by lowering the risk of vascular risk factors, including CHD, hypertension, T2DM, and hyperlipidemia. In brief, we elucidated another modifiable factor for IS and implied that maintaining sufficient muscle mass may reduce the risk of such disease.

Effect of Sarcopenic Obesity on Weight Loss Outcomes and Quality of Life after Laparoscopic Sleeve Gastrectomy: A Retrospective Cohort Study

BACKGROUND

Sarcopenic obesity may affect the health outcome of people with obesity after laparoscopic sleeve gastrectomy (LSG). To assess the impact of sarcopenic obesity (SO) on weight loss outcomes and improvement of quality of life after LSG.

MATERIALS AND METHODS

This observational study included patients who underwent LSG with SO (99 patients) or without SO (146 patients) from a single center. The primary endpoint was weight loss and disease-specific quality of life in patients with or without SO after the operation. Fat-free mass (FFM) and fat mass (FM) were calculated based on the L3-level images of preoperative CT scans. SO was diagnosed if FM/FFM ≥ 0.80.

RESULTS

Operative time and postoperative hospital stay days were longer in the SO group (p < 0.001). After LSG, weight, BMI, and EBMI were significantly lower in the NSO group than in the SO group (all P < 0.05), while %EWL and the number of patients with %EWL ≥ 100% were significantly lower in the SO group (both p < 0.05). The total BAROS scores of patients in the NSO group were higher than those in the SO group (p < 0.05). Additionally, the MA II questionnaire assessment showed a lower percentage of "very good" and "good" outcomes in the SO group (p < 0.05).

CONCLUSIONS

Patients with SO take a slower rate, longer time to reach the ideal weight, and lower quality of life self-ratings than NSO patients after LSG. Thus, preoperative evaluation and tailoring rehabilitation guidance for people with SO should be accounted.

Would Combination Be Better: Swimming Exercise and Intermittent Fasting Improve High-Fat Diet-Induced Nonalcoholic Fatty Liver Disease in Obese Rats via the miR-122-5p/SREBP-1c/CPT1A Pathway

Background

Swimming and intermittent fasting can both improve obesity-induced NAFLD, but which of the two is more effective and whether the combination of the two has a superimposed effect is inconclusive.

Methods

The model of NAFLD in obese rats was established by a high-fat diet and performed swimming, intermittent fasting, and a combination of both interventions for 8 weeks. Serum lipids and enzyme activity were measured by an automatic biochemical analyzer. Liver morphostructural analysis was observed by transmission electron microscopy, and morphology was observed by HE staining. RT‒PCR was used to detect the mRNA level.

Results

Morphology and microstructure of the liver of model rats were impaired, with the upregulation of miR-122-5p, SREBP-1c, FASN and ACC1. Eight weeks of swimming exercise, intermittent fasting and the combination of both attenuate these effects, manifested by the downregulation of miR-122-5p and upregulation of CPT1A mRNA levels. There was no significant stacking effect of the combination of the swimming and intermittent fasting interventions.

Conclusion

NAFLD leads to pathology in model rats. Eight weeks of swimming exercise, intermittent fasting and the combination of both can inhibit miR-122-5p and improve hepatic lipid metabolism, while no significant additive effects of combining the interventions were found.

The relationship between sarcopenic obesity and changes in quadriceps muscle thickness and echo intensity in patients with stroke

BACKGROUND

Research findings on skeletal muscle degeneration in post-stroke sarcopenic obesity are limited. Thus, this study aimed to investigate the association between post-stroke sarcopenic obesity and quantitative and qualitative changes in skeletal muscles.

METHODS

This was a cross-sectional study conducted on patients with stroke admitted to the convalescent rehabilitation ward. For skeletal muscle assessment, an ultrasound system was used to measure quadriceps muscle thickness and echo intensity (QMT and QEI) on the paretic and non-paretic sides. Sarcopenic obesity was defined as the presence of both sarcopenia and obesity. Multiple regression analysis was performed to determine the relationships between sarcopenic obesity and QMT and QEI.

RESULTS

A total of 130 patients with stroke were included in this study (mean age: 69.4 ± 12.7 years). The prevalence of sarcopenic obesity was 23.1%. The multiple regression analysis showed that sarcopenic obesity was significantly negatively associated with QMT on both the paretic and non-paretic sides (paretic side: β =  -0.28, p < 0.001; non-paretic side: β =  -0.37, p < 0.001) and significantly positively associated with QEI (paretic side β = 0.21, p = 0.034; non-paretic side: β = 0.20, p = 0.029).

CONCLUSIONS

Post-stroke sarcopenic obesity was independently associated with quantitative and qualitative changes in skeletal muscles on both the paretic and non-paretic sides.

The agreement of low lean mass with obesity using different definitions and its correlation with hyperuricemia

Background

The agreement on the identification of sarcopenic obesity remains elusive, and its association with hyperuricemia remains unestablished. This study sought to evaluate the agreement of low lean mass (LLM) with obesity and its correlation with hyperuricemia.

Methods

A total of 25,252 study participants, comprising 4,597 individuals with hyperuricemia, were obtained from the National Health and Nutrition Examination Survey spanning the years 1999-2006 and 2011-2018. LLM with obesity was characterized by the coexistence of LLM, determined by the ratio of appendicular lean mass to body mass index (BMI), and three categories of obesity including BMI, body fat percentage (BF%), and waist circumference (WC). We employed Cohen's kappa to evaluate the agreement among the different diagnostic criteria and implemented survey multiple logistic regression and stratified analyses to explicate the connection between LLM with obesity and the risk of hyperuricemia.

Results

When defining obesity using BF%, BMI, and WC, the prevalence of LLM with obesity varied from 6.6 to 10.1%, with moderate-to-strong agreement. In the fully adjusted model, individuals with LLM or any of the three types of obesity exhibited notably elevated odds of developing hyperuricemia. Likewise, participants with LLM and obesity had 2.70 (LLM + BMI), 2.44 (LLM + BF%), and 3.12 (LLM + WC) times the risk of hyperuricemia, respectively, compared with healthy individuals. The association between LLM with obesity and hyperuricemia remained stable and significant across different age and sex subgroups.

Conclusion

When employing the three definitions of obesity, the incidence of LLM with obesity was not high, and the diagnostic agreement was relatively good. The participants with LLM and obesity exhibited an increased risk of hyperuricemia.

Approaching the Sarcopenic Patient with Nonalcoholic Steatohepatitis-related Cirrhosis

Sarcopenia is a well-known complication of chronic liver disease (CLD), and it is almost always observed in patients with cirrhosis, at least in those with decompensated disease. Since nonalcoholic fatty liver disease (NAFLD), recently renamed metabolic dysfunction-associated steatotic liver disease (MASLD), is becoming the leading cause of end-stage liver disease, a new scenario characterized by the frequent coexistence of NAFLD, obesity, and sarcopenia is emerging. Although it is not yet resolved whether the bidirectional relationship between sarcopenia and NAFLD subtends causal determinants, it is clear that the interaction of these two conditions is associated with an increased risk of poor outcomes. Notably, during the course of CLD, deregulation of the liver-muscle-adipose tissue axis has been described. Unfortunately, owing to the lack of properly designed studies, specific therapeutic guidelines for patients with sarcopenia in the context of NAFLD-related CLD have not yet been defined. Strategies aimed to induce the loss of fat mass together with the maintenance of lean body mass seem most appropriate. This can be achieved by properly designed diets integrated with specific nutritional supplementations and accompanied by adequate physical exercise. Future studies aiming to add to the knowledge of the correct assessment and approach to sarcopenia in the context of NAFLD-related CLD are eagerly awaited.

Sarcopenic obesity is part of obesity paradox in dementia development: evidence from a population-based cohort study

BACKGROUND

Sarcopenic obesity, a clinical and functional condition characterized by the coexistence of obesity and sarcopenia, has not been investigated in relation to dementia risk and its onset.

METHODS

We included 208,867 participants from UK biobank, who aged 60 to 69 years at baseline. Dementia diagnoses were identified using hospital records and death register data. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models to evaluate the associations of obesity, sarcopenia, and sarcopenic obesity with dementia risk, stratified by sex. Stratified analyses were performed across dementia-related polygenic risk score (PRS). Restricted mean survival time models were established to estimate the difference and 95%CIs of dementia onset across different status. Additionally, linear regression models were employed to estimate associations of different status with brain imaging parameters. The mediation effects of chronic diseases were also examined.

RESULTS

Obese women with high PRS had a decreased risk (HR = 0.855 [0.761-0.961]), but obese men with low PRS had an increased risk (HR = 1.223 [1.045-1.431]). Additionally, sarcopenia was associated with elevated dementia risk (HRwomen = 1.323 [1.064-1.644]; HRmen = 2.144 [1.753-2.621]) in those with low PRS. Among those with high PRS, however, the association was only significant in early-life (HRwomen = 1.679 [1.355-2.081]; HRmen = 2.069 [1.656-2.585]). Of note, sarcopenic obesity was associated with higher dementia risk (HRwomen = 1.424 [1.227-1.653]; HRmen = 1.989 [1.702-2.323]), and results remained similar stratified by PRS. Considering dementia onset, obesity was associated with dementia by 1.114 years delayed in women, however, 0.170 years advanced in men. Sarcopenia (women: 0.080 years; men: 0.192 years) and sarcopenic obesity (women: 0.109 years; men: 0.511 years) respectively advanced dementia onset. Obesity, sarcopenia, and sarcopenic obesity were respectively related to alterations in different brain regions. Association between sarcopenic obesity and dementia was mediated by chronic diseases.

CONCLUSIONS

Sarcopenic obesity and sarcopenia were respectively associated with increased dementia risk and advanced dementia onset to vary degree. The role of obesity in dementia may differ by sex and genetic background.

The OPTIFAST total and partial meal replacement programme reduces cardiometabolic risk in adults with obesity: Secondary and exploratory analysis of the OPTIWIN study

AIM

The effects of weight loss with a partial or total meal replacement programme (MRP) on atherosclerotic cardiovascular disease (ASCVD) risk factors are not fully understood, in particular in people at higher CV risk. In the 52-week randomized controlled OPTIWIN study in men and women with obesity, meal replacement programme (total for first 26 weeks, partial for the ensuing 26 weeks) with OPTIFAST (OP) resulted in significantly greater weight loss compared with a low-calorie food-based (FB) dietary plan, both as part of a comprehensive lifestyle intervention [OP (n = 135)/FB (n = 138) week 26: -12.4%/-6.0%, p < .001; week 52: -10.5%/-5.5%, p < .001]. Here, we examined effects on ASCVD risk factors and 10-year ASCVD risk.

MATERIALS AND METHODS

Participants with body mass index 30-55 kg/m2 and age 18-70 years, and not on anti-obesity medications, were recruited. The effects on systolic and diastolic blood pressure (SBP, DBP), lipid parameters and 10-year ASCVD risk were analysed as changes over time using linear mixed models. Subgroup analyses were conducted for changes in SBP, DBP and ASCVD risk by categories of age (<40, 40-59, ≥60 years), baseline SBP (

RESULTS

Baseline characteristics were well balanced (OP/FB females 86%/79%, mean age 47/47 years, body mass index 38.4/39.2 kg/m2 , 10-year ASCVD risk <5% 87%/74%, dysglycaemia 52%/50%). At week 26, SBP/DBP were significantly reduced with OP versus FB, and a greater proportion achieved BP ≤130/80 mmHg [odds ratio 2.11 (95% confidence interval 1.10, 4.03), p = .024]. All lipid parameters as well as 10-year ASCVD risk were significantly improved with OP versus FB. A similar, but slightly attenuated pattern was observed at 52 weeks. Across subgroups, greater reductions for SBP, DBP and ASCVD risk were generally seen with OP versus FB with quantitatively higher baseline SBP and age, and in men.

CONCLUSIONS

In people with obesity at low ASCVD risk, OP significantly reduced cardiovascular risk factors and 10-year predicted risk for ASCVD.

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Key Words

• blood pressure
• body weight
• caloric restriction
• clinical trial
• heart disease risk factors
• obesity management

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MESH Headings

• Adult
• Male
• Humans
• Female
• Middle Aged
• Adolescent
• Young Adult
• Aged
• Obesity/complications
• Obesity/epidemiology
• Blood Pressure
• Risk Factors
• Weight Loss
• Atherosclerosis
• Lipids
• Hypertension/drug therapy

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Grants

• Nestlé Health Science

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Affiliation(s)

Jamy D Ard Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
Ian J Neeland Harrington Heart and Vascular Institute, University Hospitals Cleveland Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
Amy E Rothberg University of Michigan, Ann Arbor, Michigan, USA
Robert J Chilton University of Texas Health Science Center, San Antonio, Texas, USA
Daniel de Luis Center of Investigation of Endocrinlogy and Nutrition, University of Valladolid, Hospital clínico Universitario de Valladolid, Valladolid, Spain
Sarah S Cohen EpidStrategies, A Division of Tox Strategies Inc., Katy, Texas, USA
Odd Erik Johansen Nestlé Health Science, Lausanne, Switzerland

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Sarcopenic obesity in cancer

BACKGROUND

Sarcopenic obesity is a relatively new term. It is a clinical condition characterized by sarcopenia (loss of muscle mass and function) and obesity (increase in fat mass) that mainly affects older adults. As the incidence of sarcopenia and obesity increases worldwide, sarcopenic obesity is becoming a greater problem also in cancer patients. In fact, sarcopenic obesity is associated with poorer treatment outcomes, longer hospital stays, physical disability, and shorter survival in several cancers. Oxidative stress, lipotoxicity, and systemic inflammation, as well as altered expression of skeletal muscle anti-inflammatory myokines in sarcopenic obesity, are also associated with carcinogenesis.

CONCLUSIONS

Reported prevalence of sarcopenic obesity in cancer varies because of heterogeneity in definitions and variability in diagnostic criteria used to estimate the prevalence of sarcopenia and obesity. Therefore, the aim of this review is to describe the definitions, prevalence, and diagnostic criteria as well as the mechanisms that cancer has in common with sarcopenic obesity.

Associations between sarcopenic obesity and risk of cardiovascular disease: A population-based cohort study among middle-aged and older adults using the CHARLS

BACKGROUND

Previous studies have demonstrated that sarcopenia was associated with a high risk of cardiovascular disease (CVD). Nevertheless, little is known about the associations between sarcopenic obesity/possibly sarcopenic obesity and the risk of CVD among senior and middle-aged adults.

METHODS

Utilizing the nationally representative data from the China Health and Retirement Longitudinal Study (CHARLS), a sum of 7703 individuals aged at least 45 years were divided into four groups. The effects of sarcopenic obesity and possibly sarcopenic obesity on CVD were calculated using Cox proportional hazards regression models. Non-sarcopenic participants with optimal body mass index (BMI) or waist circumference (WC) served as a control group.

RESULTS

Sarcopenic obesity were related to increased risks of CVD (HR = 1.39; 95% CI = 1.16-1.67), heart disease (HR = 1.36; 95% CI = 1.10-1.67) and stroke (HR = 1.40; 95% CI = 1.02-1.92) compared with the optimal reference group. Similarly, the risk of CVD, heart disease and stroke increased by 0.34, 0.28 and 0.39 times in obese people with possible sarcopenia compared to the control group. Sensitivity analysis identified similar results to those described above. Patients with sarcopenia and a BMI ≥28.0 kg/m2 had a 1.47- and 1.48-fold risk of developing CVD and heart disease than controls.

CONCLUSION

Sarcopenic obesity and possibly sarcopenic obesity are positively associated with the development of CVD. The middle-aged and elderly population should prevent obesity and maintain muscle mass through some interventions such as weight control and moderate exercise, which may reduce the CVD risk.

Association between different skeletal muscle mass indices, physical function, and inflammation in obese pre-frail older adults

OBJECTIVES

There is lack of consensus on measurement of muscle mass and quality in obese older adults. We aim to evaluate the association of four muscle mass indices (appendicular skeletal muscle mass (ASM) over height2(ASMIht), ASM/weight (ASMwt), ASM/body fat percentage (ASMbfp)and ASM/body mass index (BMI) ASMIbmi) with physical function and inflammation in pre-frail obese older adults.

METHODS

Cross-sectional study of 407 community dwelling pre-frail older adults. Data on demographics, cognition, and physical function(gait speed, handgrip strength (HGS) and Short Physical Performance Battery (SPPB) test), body composition and inflammation biomarkers were collected. Participants were analysed based on BMI tertiles(T1 lowest,T3 highest).

RESULTS

The mean age was 72.67 years, mean BMI 25.42 kg/m2 and 59.5 % were females. Participants in T3 had a mean BMI of 30.75 kg/m2, younger with lower education levels, multimorbidity, polypharmacy and lower prevalence of sarcopenia. In BMI T3, ASMIbmi was significantly associated with EQ-5D index (β 0.53, 95 % CI 0.04 to 1.03, p = 0.033),HGS (β 5.28, 95 % CI 0.27 to 10.29, p = 0.039), SPPB (β 2.19, 95 % CI 0.47 to 3.91, p = 0.013) and IL-6 (β -4.13, 95 % CI -7.46 to -0.81, p = 0.017). ASMIwt was associated with EQ-5D index (β 0.17, 95 % CI 0.02 - 0.33, p = 0.047). ASMbfp was associated with HGS (β 6.97, 95 % CI 0.051 to 13.92, p = 0.049). There was significant association of HGS with all muscle mass indices in BMI T2, and ASMbfpin BMI T1.

CONCLUSION

ASMIbmi was significantly associated with SPPB, HGS, EQ-5D index and IL-6 in BMI T3. ASMbfp was associated with HGS in all the tertiles. Our results need further validation at population level.

Sarcopenia, sarcopenic obesity, and arterial stiffness among older adults

Background

Aging is associated with a higher prevalence of sarcopenia, sarcopenic obesity (SO), and increased arterial stiffening, with possible detrimental effects on morbidity and mortality. The aim of this study was to assess the relationships between sarcopenia, SO, and different indexes of arterial stiffness in older adults.

Methods

A total of 77 hospitalized patients (mean age 78.68 ± 9.65 years) were evaluated, obtaining anthropometric variables, biochemical samples, handgrip test, and body composition assessment. Arterial stiffness was evaluated by measuring both carotid-femoral pulse wave velocity (cfPWV), a proxy for central stiffness, and cardio-ankle vascular index (CAVI), as well as considering peripheral arteries. The population was sorted into four subgroups: obese, sarcopenic, SO, and controls.

Results

The highest CAVI (11.31 ± 2.58) was found in sarcopenic patients. SO had the highest value of cfPWV (15.18 ± 8.44 m/s), even after adjustment for significant covariates. In multiple regressions, SO diagnosis resulted as a significant predictor of cfPWV (p = 0.03, R2 = 0.20), and sarcopenia diagnosis resulted as a predictor of CAVI (p = 0.042, R2 = 0.12).

Conclusions

In conclusion, a positive correlation is found between sarcopenia, SO, and arterial stiffness among older subjects. In particular, greater central arterial stiffness is associated with SO, outlining a remarkable effect on the cardiovascular risk profile.

Immunogenetic Aspects of Sarcopenic Obesity

Sarcopenic obesity (SO) is a combination of obesity and sarcopenia, with diagnostic criteria defined as impaired skeletal muscle function and altered body composition (e.g., increased fat mass and reduced muscle mass). The mechanism of SO is not yet perfectly understood; however, the pathogenesis includes aging and its complications, chronic inflammation, insulin resistance (IR), and hormonal changes. Genetic background is apparent in the pathogenesis of isolated obesity, which is most often polygenic and is characterized by the additive effect of various genetic factors. The genetic etiology has not been strictly established in SO. Still, many data confirm the existence of pathogenic gene variants, e.g., Fat Mass and Obesity Associated Gene (FTO), beta-2-adrenergic receptor (ADRB2) gene, melanocortin-4 receptor (MC4R) and others with obesity. The literature on the role of these genes is scarce, and their role has not yet been thoroughly established. On the other hand, the involvement of systemic inflammation due to increased adipose tissue in SO plays a significant role in its pathophysiology through the synthesis of various cytokines such as monocyte chemoattractant protein-1 (MCP-1), IL-1Ra, IL-15, adiponectin or CRP. The lack of anti-inflammatory cytokine (e.g., IL-15) can increase SO risk, but further studies are needed to evaluate the exact mechanisms of implications of various cytokines in SO individuals. This manuscript analyses various immunogenetic and non-genetic factors and summarizes the recent findings on immunogenetics potentially impacting SO development.

The Vicious Cycle of Type 2 Diabetes Mellitus and Skeletal Muscle Atrophy: Clinical, Biochemical, and Nutritional Bases

Today, type 2 diabetes mellitus (T2DM) and skeletal muscle atrophy (SMA) have become increasingly common occurrences. Whether the onset of T2DM increases the risk of SMA or vice versa has long been under investigation. Both conditions are associated with negative changes in skeletal muscle health, which can, in turn, lead to impaired physical function, a lowered quality of life, and an increased risk of mortality. Poor nutrition can exacerbate both T2DM and SMA. T2DM and SMA are linked by a vicious cycle of events that reinforce and worsen each other. Muscle insulin resistance appears to be the pathophysiological link between T2DM and SMA. To explore this association, our review (i) compiles evidence on the clinical association between T2DM and SMA, (ii) reviews mechanisms underlying biochemical changes in the muscles of people with or at risk of T2DM and SMA, and (iii) examines how nutritional therapy and increased physical activity as muscle-targeted treatments benefit this population. Based on the evidence, we conclude that effective treatment of patients with T2DM-SMA depends on the restoration and maintenance of muscle mass. We thus propose that regular intake of key functional nutrients, along with guidance for physical activity, can help maintain euglycemia and improve muscle status in all patients with T2DM and SMA.

Sarcopenia and Diabetes: A Detrimental Liaison of Advancing Age

Sarcopenia is an age-related clinical complaint characterized by the progressive deterioration of skeletal muscle mass and strength over time. Type 2 diabetes (T2D) is associated with faster and more relevant skeletal muscle impairment. Both conditions influence each other, leading to negative consequences on glycemic control, cardiovascular risk, general health status, risk of falls, frailty, overall quality of life, and mortality. PubMed/Medline, Scopus, Web of Science, and Google Scholar were searched for research articles, scientific reports, observational studies, clinical trials, narrative and systematic reviews, and meta-analyses to review the evidence on the pathophysiology of di-abetes-induced sarcopenia, its relevance in terms of glucose control and diabetes-related outcomes, and diagnostic and therapeutic challenges. The review comprehensively addresses key elements for the clinical definition and diagnostic criteria of sarcopenia, the pathophysiological correlation be-tween T2D, sarcopenia, and related outcomes, a critical review of the role of antihyperglycemic treatment on skeletal muscle health, and perspectives on the role of specific treatment targeting myokine signaling pathways involved in glucose control and the regulation of skeletal muscle metabolism and trophism. Prompt diagnosis and adequate management, including lifestyle inter-vention, health diet programs, micronutrient supplementation, physical exercise, and pharmaco-logical treatment, are needed to prevent or delay skeletal muscle deterioration in T2D.

Comparing the efficacy of low-load resistance exercise combined with blood flow restriction versus conventional-load resistance exercise in Chinese community-dwelling older people with sarcopenic obesity: a study protocol for a randomised controlled trial

INTRODUCTION

Sarcopenic obesity (SO) is characterised by decreased muscle mass, diminished muscle strength and/or reduced physical performance and a high percentage of body fat (PBF). Conventional-load resistance exercise (CRE) may be difficult for older people with SO owing to their declining physical functions. Low-load resistance exercise (LRE) combined with blood flow restriction (BFR; LRE-BFR) is a viable alternative to CRE for improving muscle mass and strength and potential exercise mode for managing SO. This study has two objectives: (1) to comprehensively evaluate the efficacy of CRE and LRE-BFR in improving body composition, muscle strength, physical performance, haematological parameters, cardiovascular disease (CVD) risk factors and quality of life and (2) to compare the efficacy of CRE and LRE-BFR and explore their potential mechanisms.

METHODS AND ANALYSIS

This work is a 12-week assessor-blinded randomised clinical trial that will be conducted thrice a week. Sarcopenia will be defined using the Asian Working Group for Sarcopenia 2019, and obesity will be determined using the criteria developed by the World Health Organization. Community-dwelling older people aged ≥ 65 years will be screened as the participants using inclusion and exclusion criteria. A total of 33 participants will be randomised into a CRE group (n = 11), an LRE-BFR group (n = 11) and a control group that will be given only health education (n = 11). The primary outcomes will be knee extensor strength and PBF, and the secondary outcomes will be body composition, anthropometric measurements, muscle strength of upper limbs, physical performance, haematological parameters, CVD risk factors and quality of life. The outcomes will be measured at the baseline (week 0), end of the intervention (week 12) and follow up (week 24). All the collected data will be analysed following the intention-to-treat principle.

ETHICS AND DISSEMINATION

The Ethics Research Committee has approved this study (approval No. CMEC-2022-KT-51). Changes or developments in this study will be reported at www.chictr.org.cn .

TRIAL REGISTRATION

ChiCTR2300067296 (3 January 2023).

Comparative effectiveness of multiple different treatment regimens for nonalcoholic fatty liver disease with type 2 diabetes mellitus: a systematic review and Bayesian network meta-analysis of randomised controlled trials

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) are closely related and mutually contribute to the disease's development. There are many treatment options available to patients. We provide a comprehensive overview of the evidence on the treatment effects of several potential interventions for NAFLD with T2DM.

METHODS

This systematic review and network meta-analysis included searches of PubMed, Embase, Cochrane Library, and Web of Science from inception to June 30, 2023, for randomised controlled trials of treatment of NAFLD with T2DM. We performed Bayesian network meta-analyses to summarise effect estimates of comparisons between interventions. We applied the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) frameworks to rate all comparative outcomes' certainty in effect estimates, categorise interventions, and present the findings. This study was registered with PROSPERO, CRD42022342373.

RESULTS

Four thousand three hundred and sixty-nine records were retrieved from the database and other methods, of which 24 records were eligible for studies enrolling 1589 participants. Eight clinical indicators and 14 interventions were finally in focus. Referring to the lower surface under the cumulative ranking curves (SUCRA) and the league matrix table, exenatide and liraglutide, which are also glucagon-like peptide-1 receptor agonists (GLP-1RAs), showed excellent potential to reduce liver fat content, control glycemia, reduce body weight, and improve liver function and insulin resistance. Exenatide was more effective in reducing glycated haemoglobin (HbA1c) (mean difference (MD) 0.32, 95%CI 0.12 to 0.52), lowering BMI (MD 0.81, 95%CI 0.18 to 1.45), and lowering alanine transaminase (ALT) (MD 10.96, 95%CI 5.27 to 16.66) compared to liraglutide. However, this evidence was assessed as low certainty. Omega-3 was the only intervention that did not have a tendency to lower HbA1c, with standard-treatment (STA-TRE) as reference (MD - 0.17, 95%CI - 0.42 to 0.07). Glimepiride is the only intervention that causes an increase in ALT levels, with standard-treatment (STA-TRE) as reference (MD - 11.72, 95%CI - 17.82 to - 5.57). Based on the available evidence, the treatment effects of pioglitazone, dapagliflozin, and liraglutide have a high degree of confidence.

CONCLUSIONS

The high confidence mandates the confident application of these findings as guides for clinical practice. Dapagliflozin and pioglitazone are used for glycaemic control in patients with NAFLD combined with T2DM, and liraglutide is used for weight loss therapy in patients with abdominal obesity. The available evidence does not demonstrate the credibility of the effectiveness of other interventions in reducing liver fat content, visceral fat area, ALT, and insulin resistance. Future studies should focus on the clinical application of GLP-1Ras and the long-term prognosis of patients.