Mechanisms of body fat distribution and gluteal-femoral fat protection against metabolic disorders

Obesity is a major health problem that affects millions of individuals, and it is associated with metabolic diseases including insulin resistance (IR), type 2 diabetes (T2D), and cardiovascular diseases (CVDs). However, Body fat distribution (BFD) rather than crude obesity is now considered as a more accurate factor associated with these diseases. The factors affecting BFD vary, from genetic background, epigenetic factors, ethnicity, aging, hormonal changes, to lifestyle and medication consumptions. The main goal of controlling BFD comes from the fact that fat accumulation in different depots has a different effect on the overall health and metabolic health of individuals. It is well established that fat storage in the abdominal visceral depot is associated with metabolic disorder occurrence, while gluteal-femoral subcutaneous fat depot seems to be protective against these diseases. In this paper, we will summarize the factors affecting fat distribution. Then, we will present evidence connecting gluteal-femoral fat depot with protection against metabolic disorders including IR, T2D, and CVDs. Finally, we will list the suggested mechanisms that lead to this protective effect. The abstract is visualized in Graphical Abstract

Mediators of Impaired Adipogenesis in Obesity-Associated Insulin Resistance and T2DM

Obesity has become a global health issue due to its high prevalence and associated comorbidities including insulin resistance (IR) and type 2 diabetes mellitus (T2DM). Obesity is associated with the expansion of adipose tissues through hypertrophy of mature adipocytes and differentiation of local preadipocytes in a process known as adipogenesis to store excess triacylglycerols (TAGs). Impairment of adipogenesis leads to ectopic fat deposition in skeletal muscles, liver, and kidneys, triggering IR in these tissues and increased risk of T2DM. Many factors contribute to impaired adipogenesis including obesity-associated mild chronic inflammation, oxidative stress, and fatty acid signaling. This review summarizes recent literature covering mediators of impaired adipogenesis and underlying molecular pathways

From an Apple to a Pear: Moving Fat around for Reversing Insulin Resistance.

Type 2 diabetes (T2D) is a chronic condition where the body is resistant to insulin, leading to an elevated blood glucose state. Obesity is a main factor leading to T2D. Many clinical studies, however, have described a proportion of obese individuals who express a metabolically healthy profile, whereas some lean individuals could develop metabolic disorders. To study obesity as a risk factor, body fat distribution needs to be considered rather than crude body weight. Different individuals' bodies favor storing fat in different depots; some tend to accumulate more fat in the visceral depot, while others tend to store it in the femoral depot. This tendency relies on different factors, including genetic background and lifestyle. Consuming some types of medications can cause a shift in this tendency, leading to fat redistribution. Fat distribution plays an important role in the progression of risk of insulin resistance (IR). Apple-shaped individuals with enhanced abdominal obesity have a higher risk of IR compared to BMI-matched pear-shaped individuals, who store their fat in the gluteal-femoral depots. This is related to the different adipose tissue physiology between these two depots. In this review, we will summarize the recent evidence highlighting the underlying protective mechanisms in gluteal-femoral subcutaneous adipose tissues compared to those associated with abdominal adipose tissue, and we will revise the recent evidence showing antidiabetic drugs that impact fat distribution as they manage the T2D condition.This research was funded by the Qatar National Research Fund (QNRF), grant number NPRP13S-1230-190008

Prevalence and Predictors of Insulin Resistance in Non-Obese Healthy Young Females in Qatar

The state of Qatar suffers from diabetes epidemic due to obesity-associated metabolic syndrome. However, the prevalence of insulin resistance prior to obesity, which could play an important role in the high prevalence of diabetes, has not yet been described. This study aims to compare the prevalence of insulin resistance in apparently healthy non-obese and obese participants from Qatar and identify the predictors of insulin resistance in different body massindex(BMI)-groups. In this cross-sectional study, 150 young healthy females from Qatar were dichotomized into four groups (underweight, normal weight, overweight and obese) based on their BMI. Anthropometric measures as well as fasting plasma levels of lipids, adipokines, blood glucose and insulin were recorded. The prevalence of insulin resistance as per homeostatic model assessment of insulin resistance (HOMA-IR) was estimated and differences between insulin sensitive and insulin resistant were compared. Linear models were used to identify predictors of insulin resistance in every BMI group. Prevalence of insulin resistance in non-obese healthy females from Qatar ranges between 7% and 37%and increases with BMI. Overall, predictors of insulin resistance in the Qatari population are triglycerides/high-density lipoprotein (HDL) ratio and free fat mass but vary according to the BMI group. The main predictors were triglycerides in normal weight, triglycerides/HDL in overweight and triglycerides/HDL and interleukin-6 (IL-6) in obese individuals. The high prevalence of insulin resistance in non-obese Qataris may partially explain diabetes epidemic. Larger studies are warranted to confirm these findings and identify underlying causes for insulin resistance in non-obese individuals in Qatar, aiming at targeted intervention before diabetes onsetThis project was funded by Qatar University (grant number QUST-CAS-FALL-14\15-35). The publication of this article was funded by the Qatar National Library

Editorial: OMICS-based approaches in sports research volume II.

OMICS approaches, including genomics, epigenomics, transcriptomics, proteomics, and metabolomics, continue to provide invaluable tools for better understanding of the molecular mechanisms underlying various physiological and pathological functions in health and disease. The rapid advancement of these tools and emergence of new ones is progressively filling the gap in our understanding of the complex networks that determine the structure, function, and dynamics of organisms. These advancements have greatly empowered discoveries of novel diagnostic and prognostic biomarkers as well as therapeutic targets, and provided a better guidance to precision and personalized medicine

Profiling the Oral Microbiome and Plasma Biochemistry of Obese Hyperglycemic Subjects in Qatar

The present study is designed to compare demographic characteristics, plasma biochemistry, and the oral microbiome in obese ( = 37) and lean control ( = 36) subjects enrolled at Qatar Biobank, Qatar. Plasma hormones, enzymes, and lipid profiles were analyzed at Hamad Medical Cooperation Diagnostic Laboratory. Saliva microbiome characterization was carried out by 16S rRNA amplicon sequencing using Illumina MiSeq platform. Obese subjects had higher testosterone and sex hormone-binding globulin (SHBG) concentrations compared to the control group. A negative association between BMI and testosterone ( < 0.001, r = -0.64) and SHBG ( < 0.001, r = -0.34) was observed. Irrespective of the study groups, the oral microbiome was predominantly occupied by , , and species. A generalized linear model revealed that the Firmicutes/Bacteroidetes ratio (2.25 ± 1.83 vs. 1.76 ± 0.58; corrected -value = 0.04) was higher, and phylum Fusobacteria concentration (4.5 ± 3.0 vs. 6.2 ± 4.3; corrected -value = 0.05) was low in the obese group compared with the control group. However, no differences in microbiome diversity were observed between the two groups as evaluated by alpha (Kruskal-Wallis ≥ 0.78) and beta (PERMANOVA = 0.37) diversity indexes. Certain bacterial phyla (Acidobacteria, Bacteroidetes, Fusobacteria, Proteobacteria, Spirochaetes, and Firmicutes/Bacteroidetes) were positively associated ( = 0.05, r ≤ +0.5) with estradiol, fast food consumption, creatinine, breastfed during infancy, triglycerides, and thyroid-stimulating hormone concentrations. In conclusion, no differences in oral microbiome diversity were observed between the studied groups. However, the Firmicutes/Bacteroidetes ratio, a recognized obesogenic microbiome trait, was higher in the obese subjects. Further studies are warranted to confirm these findings in a larger cohort.Qatar National Research Fun

Impact of Moderate Physical Activity on Inflammatory Markers and Telomere Length in Sedentary and Moderately Active Individuals with Varied Insulin Sensitivity

Introduction: Physical activity-associated immune response plays a crucial role in the aging process. This study aimed to determine the impact of short-term moderate physical activity on cytokine levels, oxidative stress markers, and telomere length in lean/ overweight young subjects. Methods: Fasting blood samples were collected from 368 participants at Qatar Biobank. Based on their homeostatic model assessment of insulin resistance (HOMA-IR), participants were categorized as insulin sensitive (IS) or insulin resistant (IR). Subsequently, they were divided into four groups: sedentary IS (n = 90), sedentary IR (n = 90), moderately active IS (n = 94), and moderately active IR (n = 94). Moderate physical activity was defined as walking at least two days per week for more than 150 minutes, as determined by physical activity questionnaires. Serum samples were analyzed for circulating inflammatory cytokines (IL-1β, IL-1RA, IL-6, IL-10, IL-22, MCP-1/CCL2, TNF-α), as well as antioxidant enzyme levels (SOD and catalase). Telomere lengths were measured in the respective DNA samples. Results: Moderately active IR participants exhibited significantly lower SOD activity, while catalase activity did not show significant differences. Moderately active IS participants had higher IL-6 and IL-10 levels compared to sedentary IS participants, with no significant differences observed in the IR counterparts. Telomere length did not significantly differ between the physically active and sedentary groups. Conclusion: This study highlights the potential anti-inflammatory and anti-oxidative stress effects of moderate physical activity in individuals with insulin sensitivity and insulin resistance. However, no significant changes in telomere length were observed, suggesting a complex relationship between physical activity and the aging process. Further research is needed to fully understand the underlying mechanisms and optimize the balance between anti-inflammation and anti-oxidation through exercise and lifestyle adjustments.</p