Beneficial effects of subcutaneous fat transplantation on metabolism

Development of a CT-assessed adiposity nomogram for predicting outcome in localized ccRCC

PURPOSE

This study aimed to develop and validate a computed tomography-based nomogram assessing visceral and subcutaneous adiposity for predicting outcomes in localized clear cell renal cell carcinoma (ccRCC).

METHODS

A cohort of 364 patients with pathologically confirmed ccRCC participated in this retrospective study, with 254 patients assigned to the training set and 110 to the validation set (a 7:3 distribution ratio). The adipose score (AS) was generated using the least absolute shrinkage and selection operator Cox regression. Subsequently, a nomogram was constructed by integrating the clinical independent predictor with the AS to predict disease-free survival (DFS) in localized ccRCC after surgery. The performance of the nomogram was compared with the University of California, Los Angeles, Integrated Staging System (UISS), and the Stage, Size, Grade, and Necrosis (SSIGN) score.

RESULTS

In both the training and validation cohorts, the nomogram exhibited superior discrimination compared to SSIGN and UISS (C-index: 0.897 vs. 0.781 vs. 0.776 in the training cohort, and 0.752 vs. 0.596 vs. 0.686 in the validation cohort; 5 year AUC: 0.907 vs. 0.805 vs. 0.820 in the training cohort, and 0.832 vs. 0.577 vs. 0.726 in the validation cohort). Decision curve analysis (DCA) revealed a superior net benefit across a wider range of threshold probabilities for predicting 5 year DFS compared to UISS and SSIGN scores.

CONCLUSIONS

The developed prognostic nomogram demonstrated high accuracy and overall superior performance compared to existing prognostic models.

Early-Life Risk Factors for Carotid Intima-Media Thickness and Carotid Stiffness in Adolescence

Importance

Atherogenesis starts during childhood, making childhood and adolescence an important window of opportunity to prevent atherosclerotic cardiovascular disease later in life.

Objective

To identify early-life risk factors for preclinical atherosclerosis in adolescence.

Design, Setting, and Participants

This cohort study is part of the ongoing Wheezing Illness Study in Leidsche Rijn (WHISTLER) prospective birth cohort study, which includes 3005 healthy newborns born between December 2001 and December 2012 in the Leidsche Rijn area of Utrecht, the Netherlands. Eligible participants included those from the WHISTLER cohort who visited the clinic between March 2019 and October 2020 for adolescent follow-up. This study's analyses were performed in January 2024.

Exposures

Early-life growth was assessed at birth to 6 months, 5 years, and 12 to 16 years. Abdominal ultrasonography determined abdominal subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) depth. Blood pressure (BP) percentiles and body mass index (BMI) z scores were used.

Main Outcomes and Measures

Carotid ultrasonography was performed at age 12 to 16 years to assess carotid intima-media thickness (cIMT) and the distensibility coefficient (DC), established measures of preclinical atherosclerosis. Multivariable linear regression models were used to identify early-life risk factors for cIMT and DC in adolescence.

Results

In total, 232 adolescents (median [IQR] age, 14.9 [13.7-15.8] years; 121 female [52.2%]) were included. More postnatal weight gain (B = 12.34; 95% CI, 2.39 to 22.39), higher systolic BP at 5 years (B = 0.52; 95% CI, 0.02 to 1.01), more VAT at 5 years (B = 3.48; 95% CI, 1.55 to 5.40), and a larger change in VAT between 5 and 12 to 16 years (B = 3.13; 95% CI, 1.87 to 4.39) were associated with a higher cIMT in adolescence. A higher BMI (B = -2.70, 95% CI,-4.59 to -0.80) and VAT at 5 years (B = -0.56; 95% CI, -0.87 to -0.25), as well as a larger change in BMI between 5 and 12 to 16 years (B = -3.63; 95% CI, -5.66 to -1.60) were associated with a higher carotid stiffness in adolescence. On the contrary, a larger change in SAT between 5 and 12 to 16 years (B = 0.37; 95% CI, 0.16 to 0.58) was associated with a higher carotid DC in adolescence.

Conclusions and Relevance

In this cohort study of 232 participants, early-life growth parameters, and particularly abdominal VAT development, were associated with a higher cIMT and carotid stiffness in adolescence. These findings suggest that assessment of adipose tissue development during childhood can aid characterization of lifetime risk trajectories and tailoring of cardiovascular prevention and risk management strategies.

Phenotypes of Metabolic Dysfunction-Associated Steatotic Liver Disease-Associated Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) typically develops as a consequence of liver cirrhosis, but HCC epidemiology has evolved drastically in recent years. Metabolic dysfunction-associated steatotic liver disease (MASLD), including metabolic dysfunction-associated steatohepatitis, has emerged as the most common chronic liver disease worldwide and a leading cause of HCC. A substantial proportion of MASLD-associated HCC (MASLD-HCC) also can develop in patients without cirrhosis. The specific pathways that trigger carcinogenesis in this context are not elucidated completely, and recommendations for HCC surveillance in MASLD patients are challenging. In the era of precision medicine, it is critical to understand the processes that define the profiles of patients at increased risk of HCC in the MASLD setting, including cardiometabolic risk factors and the molecular targets that could be tackled effectively. Ideally, defining categories that encompass key pathophysiological features, associated with tailored diagnostic and treatment strategies, should facilitate the identification of specific MASLD-HCC phenotypes. In this review, we discuss MASLD-HCC, including its epidemiology and health care burden, the mechanistic data promoting MASLD, metabolic dysfunction-associated steatohepatitis, and MASLD-HCC. Its natural history, prognosis, and treatment are addressed specifically, as the role of metabolic phenotypes of MASLD-HCC as a potential strategy for risk stratification. The challenges in identifying high-risk patients and screening strategies also are discussed, as well as the potential approaches for MASLD-HCC prevention and treatment.

A case report on Madelung's disease and comprehensive review of the literature

BACKGROUND

Madelung's disease (MD), alternatively referred to as benign symmetric lipomatosis, multiple symmetric lipomatosis, or Launois-Bensaude syndrome, is an uncommon benign disorder marked by symmetric proliferation of adipose tissue in the head, neck, and torso regions.

CASE DESCRIPTION

In this case, the patient was a female with the late middle-aged demographic, diagnosed with Type I MD. Notably, she exhibited no prior history of alcohol consumption, and there was no family history of MD. Subsequent to the clinical diagnosis, the patient underwent medical imaging assessments to delineate the surgical parameters. Post-surgery, she demonstrated a favorable recovery trajectory, marked by the absence of any surgical complications.

RESULT

The patient underwent successful surgical excision of the lipomatous mass. Postoperatively, she had an uneventful recovery with no complications and no recurrence observed during the follow-up period of seven months.

CONCLUSION

Timely diagnosis and early surgical intervention play a pivotal role in enhancing the quality of life for individuals with MD. Preoperative medical imaging examinations function as highly effective tools, contributing to heightened surgical safety and a decreased probability of encountering complications during the surgical procedure.

BAFF neutralization impairs the autoantibody-mediated clearance of dead adipocytes and aggravates obesity-induced insulin resistance

B cell-activating factor (BAFF) is a critical TNF-family cytokine that regulates homeostasis and peripheral tolerance of B2 cells. BAFF overproduction promotes autoantibody generation and autoimmune diseases. During obesity, BAFF is predominantly produced by white adipose tissue (WAT), and IgG autoantibodies against adipocytes are identified in the WAT of obese humans. However, it remains to be determined if the autoantibodies formed during obesity affect WAT remodeling and systemic insulin resistance. Here, we show that IgG autoantibodies are generated in high-fat diet (HFD)-induced obese mice that bind to apoptotic adipocytes and promote their phagocytosis by macrophages. Next, using murine models of obesity in which the gonadal WAT undergoes remodeling, we found that BAFF neutralization depleted IgG autoantibodies, increased the number of dead adipocytes, and exacerbated WAT inflammation and insulin resistance. RNA sequencing of the stromal vascular fraction from the WAT revealed decreased expression of immunoglobulin light-chain and heavy-chain variable genes suggesting a decreased repertoire of B cells after BAFF neutralization. Further, the B cell activation and the phagocytosis pathways were impaired in the WAT of BAFF-neutralized mice. In vitro, plasma IgG fractions from BAFF-neutralized mice reduced the phagocytic clearance of apoptotic adipocytes. Altogether, our study suggests that IgG autoantibodies developed during obesity, at least in part, dampens exacerbated WAT inflammation and systemic insulin resistance.

Body composition and late-occurring chronic health conditions after autologous stem cell transplantation for lymphoma

BACKGROUND

Autologous peripheral blood stem cell transplantation (aPBSCT) is the standard of care for adults with relapsed lymphoma, yet recipients remain at risk of developing chronic health conditions (CHCs). It was hypothesized that body composition measurements of skeletal muscle and fat are associated with late-onset CHCs and nonrelapse mortality after aPBSCT.

METHODS

Leveraging the Blood or Marrow Transplant Survivor Study, we examined association between pre-aPBSCT body composition and new-onset grade 3-5 CHCs among 187 adults with lymphoma treated with aPBSCT (2011-2014) surviving ≥2 years after aPBSCT. Using computed tomography scans at the L3 level, skeletal muscle mass (skeletal muscle area and skeletal muscle density [SMD]) and body fat (subcutaneous adipose tissue and visceral adipose tissue) were measured and quantified as sex-specific z-scores. Competing risk models were built to study the impact of body composition on incident grade 3 through 5 CHCs and nonrelapse mortality (NRM) adjusting for confounders.

RESULTS

The study cohort had a median age at aPBSCT of 57 years with 63% males, 77% non-Hispanic Whites and 81% with non-Hodgkin lymphoma. The 5-year cumulative incidence of grade 3 through 5 CHCs was 47% (95% Confidence Interval, CI, 38%-56%). Each SD increase in SMD was associated with 30% reduced risk of grade 3 through 5 CHCs (95% CI, 0.50-0.96). The 10-year cumulative incidence of NRM was 16% (95% CI, 10-22). No body composition measure was associated with NRM.

CONCLUSIONS

The association between SMD and grade 3 through 5 CHCs following aPBSCT could inform development of prognostic models to identify adults with lymphoma at greatest risk of morbidity following aPBSCT.

Alzheimer Disease Pathology and Neurodegeneration in Midlife Obesity: A Pilot Study

Obesity and excess adiposity at midlife are risk factors for Alzheimer disease (AD). Visceral fat is known to be associated with insulin resistance and a pro-inflammatory state, the two mechanisms involved in AD pathology. We assessed the association of obesity, MRI-determined abdominal adipose tissue volumes, and insulin resistance with PET-determined amyloid and tau uptake in default mode network areas, and MRI-determined brain volume and cortical thickness in AD cortical signature in the cognitively normal midlife population. Thirty-two middle-aged (age: 51.27±6.12 years, 15 males, body mass index (BMI): 32.28±6.39 kg/m2) cognitively normal participants, underwent bloodwork, brain and abdominal MRI, and amyloid and tau PET scan. Visceral and subcutaneous adipose tissue (VAT, SAT) were semi-automatically segmented using VOXel Analysis Suite (Voxa). FreeSurfer was used to automatically segment brain regions using a probabilistic atlas. PET scans were acquired using [11C]PiB and AV-1451 tracers and were analyzed using PET unified pipeline. The association of brain volumes, cortical thicknesses, and PiB and AV-1451 standardized uptake value ratios (SUVRs) with BMI, VAT/SAT ratio, and insulin resistance were assessed using Spearman's partial correlation. VAT/SAT ratio was associated significantly with PiB SUVRs in the right precuneus cortex (p=0.034) overall, controlling for sex. This association was significant only in males (p=0.044), not females (p=0.166). Higher VAT/SAT ratio and PiB SUVRs in the right precuneus cortex were associated with lower cortical thickness in AD-signature areas predominantly including bilateral temporal cortices, parahippocampal, medial orbitofrontal, and cingulate cortices, with age and sex as covariates. Also, higher BMI and insulin resistance were associated with lower cortical thickness in bilateral temporal poles. In midlife cognitively normal adults, we demonstrated higher amyloid pathology in the right precuneus cortex in individuals with a higher VAT/SAT ratio, a marker of visceral obesity, along with a lower cortical thickness in AD-signature areas associated with higher visceral obesity, insulin resistance, and amyloid pathology.

Association of excess visceral fat and severe illness in hospitalized COVID-19 patients in Japan: a retrospective cohort study

BACKGROUND/OBJECTIVES

Obesity, defined by body mass index (BMI), is a well-known risk factor for the severity of coronavirus disease 2019 (COVID-19). Adipose tissue distribution has also been implicated as an important factor in the body's response to infection, and excess visceral fat (VF), which is prevalent in Japanese, may contribute significantly to the severity. Therefore, this study aimed to evaluate the association of obesity and VF with COVID-19 severe illness in Japan.

SUBJECTS/METHODS

This retrospective cohort study involved 550 COVID-19 patients admitted to a tertiary care hospital with BMI and body composition data, including VF. The primary endpoint was severe illness, including death, due to COVID-19 during hospitalization. Logistic regression analysis was applied to examine the quartiles of BMI and VF on severe illness after adjusting for covariates such as age, sex, subcutaneous fat, paraspinal muscle radiodensity, and comorbidities affecting VF (COPD, cancer within 5 years, immunosuppressive agent use).

RESULTS

The median age was 56.0 years; 71.8% were males. During hospitalization, 82 (14.9%) experienced COVID-19 severe illness. In the multivariate logistic regression analysis, Q4 of BMI was not significantly associated with severe illness compared to Q1 of BMI (OR 1.03; 95% CI 0.37-2.86; p = 0.95). Conversely, Q3 and Q4 of VF showed a higher risk for severe illness compared to Q1 of VF (OR 2.68; 95% CI 1.01-7.11; p = 0.04, OR 3.66; 95% CI 1.30-10.26; p = 0.01, respectively). Stratified analysis by BMI and adjusted for covariates showed the positive association of VF with severe illness only in the BMI < 25 kg/m2 group.

CONCLUSIONS

High BMI was not an independent risk factor for COVID-19 severe illness in hospitalized patients in Japan, whereas excess VF significantly influenced severe illness, especially in patients with a BMI < 25 kg/m2.

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.

Influence of nutritional status and body composition on postoperative events and outcome in patients treated for primary localized retroperitoneal sarcoma

BACKGROUND

Retroperitoneal sarcomas (RPS) are rare tumours of mesenchymal origin, commonly presented as a large tumour mass at time of diagnosis. We investigated the impact of body composition on outcome in patients operated on for primary localized RPS.

PATIENTS AND METHODS

We retrospectively analysed data for all patients operated on for primary RPS at our institution between 1999 and 2020. Preoperative skeletal muscle area (SMA), visceral and subcutaneous adipose tissue area (VAT and SAT) and muscle radiation attenuation (MRA) were calculated using computed tomography scans at the level of third lumbar vertebra. European Working Group on Sarcopenia in Older People (EWGSOP2) criteria were applied to define myopenia. Using maximum log-rank statistic method we determined the optimal cut-off values of body composition parameters. Myosteatosis was defined based on determined MRA cut-offs.

RESULTS

In total 58 patient were eligible for the study. With a median follow-up of 116 months, the estimated 5-year overall survival (OS) and local-recurrence free survival (LRFS) were 66.8% and 77.6%, respectively. Patients with myopenia had significantly lower 5-year OS compared to non-myopenic (p = 0.009). Skeletal muscle index and subcutaneous adipose tissue index predicted LRFS on univariate analysis (p = 0.052 and p = 0.039, respectively). In multivariate analysis high visceral-to-subcutaneous adipose tissue area ratio (VSR) independently predicted higher postoperative complication rate (89.2% vs. 10.8%, p = 0.008). Myosteatosis was associated with higher postoperative morbidity.

CONCLUSIONS

Myopenia affected survival, but not postoperative outcome in RPS. Visceral obesity, VSR (> 0.26) and myosteatosis were associated with higher postoperative morbidity. VSR was better prognostic factor than VAT in RPS.

Adipose organ dysfunction and type 2 diabetes: Role of nitric oxide

Adipose organ, historically known as specialized lipid-handling tissue serving as the long-term fat depot, is now appreciated as the largest endocrine organ composed of two main compartments, i.e., subcutaneous and visceral adipose tissue (AT), madding up white and beige/brown adipocytes. Adipose organ dysfunction manifested as maldistribution of the compartments, hypertrophic, hypoxic, inflamed, and insulin-resistant AT, contributes to the development of type 2 diabetes (T2D). Here, we highlight the role of nitric oxide (NO·) in AT (dys)function in relation to developing T2D. The key aspects determining lipid and glucose homeostasis in AT depend on the physiological levels of the NO· produced via endothelial NO· synthases (eNOS). In addition to decreased NO· bioavailability (via decreased expression/activity of eNOS or scavenging NO·), excessive NO· produced by inducible NOS (iNOS) in response to hypoxia and AT inflammation may be a critical interfering factor diverting NO· signaling to the formation of reactive oxygen and nitrogen species, resulting in AT and whole-body metabolic dysfunction. Pharmacological approaches boosting AT-NO· availability at physiological levels (by increasing NO· production and its stability), as well as suppression of iNOS-NO· synthesis, are potential candidates for developing NO·-based therapeutics in T2D.

Gut microbiota in overweight and obesity: crosstalk with adipose tissue

Overweight and obesity are characterized by excessive fat mass accumulation produced when energy intake exceeds energy expenditure. One plausible way to control energy expenditure is to modulate thermogenic pathways in white adipose tissue (WAT) and/or brown adipose tissue (BAT). Among the different environmental factors capable of influencing host metabolism and energy balance, the gut microbiota is now considered a key player. Following pioneering studies showing that mice lacking gut microbes (that is, germ-free mice) or depleted of their gut microbiota (that is, using antibiotics) developed less adipose tissue, numerous studies have investigated the complex interactions existing between gut bacteria, some of their membrane components (that is, lipopolysaccharides), and their metabolites (that is, short-chain fatty acids, endocannabinoids, bile acids, aryl hydrocarbon receptor ligands and tryptophan derivatives) as well as their contribution to the browning and/or beiging of WAT and changes in BAT activity. In this Review, we discuss the general physiology of both WAT and BAT. Subsequently, we introduce how gut bacteria and different microbiota-derived metabolites, their receptors and signalling pathways can regulate the development of adipose tissue and its metabolic capacities. Finally, we describe the key challenges in moving from bench to bedside by presenting specific key examples.

Adipose tissue depot specific expression and regulation of fibrosis-related genes and proteins in experimental obesity

Transforming growth factor beta (Tgfb) is a well-studied pro-fibrotic cytokine, which upregulates cellular communication network factor 2 (Ccn2), collagen, and actin alpha 2, smooth muscle (Acta2) expression. Obesity induces adipose tissue fibrosis, which contributes to metabolic diseases. This work aimed to analyze the expression of Tgfb, Ccn2, collagen1a1 (Col1a1), Acta2 and BMP and activin membrane-bound inhibitor (Bambi), which is a negative regulator of Tgfb signaling, in different adipose tissue depots of mice fed a standard chow, mice fed a high fat diet (HFD) and ob/ob mice. Principally, these genes were low expressed in brown adipose tissues and this difference was less evident for the ob/ob mice. Ccn2 and Bambi protein as well as mRNA expression, and collagen1a1 mRNA were not induced in the adipose tissues upon HFD feeding whereas Tgfb and Acta2 mRNA increased in the white fat depots. Immunoblot analysis showed that Acta2 protein was higher in subcutaneous and perirenal fat of these mice. In the ob/ob mice, Ccn2 mRNA and Ccn2 protein were upregulated in the fat depots. Here, Tgfb, Acta2 and Col1a1 mRNA levels and serum Tgfb protein were increased. Acta2 protein was, however, not higher in subcutaneous and perirenal fat of these mice. Col6a1 mRNA was shown before to be higher in obese fat tissues. Current analysis proved the Col6a1 protein was induced in subcutaneous fat of HFD fed mice. Notably, Col6a1 was reduced in perirenal fat of ob/ob mice in comparison to the respective controls. 3T3-L1 cells express Ccn2 and Bambi protein, whose levels were not changed by fatty acids, leptin, lipopolysaccharide, tumor necrosis factor and interleukin-6. All of these factors led to higher Tgfb in 3T3-L1 adipocyte media but did not increase its mRNA levels. Free fatty acids induced necrosis whereas apoptosis did not occur in any of the in vitro incubations excluding cell death as a main reason for higher Tgfb in cell media. In summary, Tgfb mRNA is consistently induced in white fat tissues in obesity but this is not paralleled by a clear increase of its target genes. Moreover, discrepancies between mRNA and protein expression of Acta2 were observed. Adipocytes seemingly do not contribute to higher Tgfb mRNA levels in obesity. These cells release more Tgfb protein when challenged with obesity-related metabolites connecting metabolic dysfunction and fibrosis.

Transplantation of committed pre-adipocytes from brown adipose tissue improves whole-body glucose homeostasis

Obesity and its co-morbidities including type 2 diabetes are increasing at epidemic rates in the U.S. and worldwide. Brown adipose tissue (BAT) is a potential therapeutic to combat obesity and type 2 diabetes. Increasing BAT mass by transplantation improves metabolic health in rodents, but its clinical translation remains a challenge. Here, we investigated if transplantation of 2-4 million differentiated brown pre-adipocytes from mouse BAT stromal fraction (SVF) or human pluripotent stem cells (hPSCs) could improve metabolic health. Transplantation of differentiated brown pre-adipocytes, termed "committed pre-adipocytes" from BAT SVF from mice or derived from hPSCs improves glucose homeostasis and insulin sensitivity in recipient mice under conditions of diet-induced obesity, and this improvement is mediated through the collaborative actions of the liver transcriptome, tissue AKT signaling, and FGF21. These data demonstrate that transplantation of a small number of brown adipocytes has significant long-term translational and therapeutic potential to improve glucose metabolism.

A comprehensive review of the literature on CD10: its function, clinical application, and prospects

CD10, a zinc-dependent metalloprotease found on the cell surface, plays a pivotal role in an array of physiological and pathological processes including cardiovascular regulation, immune function, fetal development, pain response, oncogenesis, and aging. Recognized as a biomarker for hematopoietic and tissue stem cells, CD10 has garnered attention for its prognostic potential in the progression of leukemia and various solid tumors. Recent studies underscore its regulatory significance and therapeutic promise in combating Alzheimer's disease (AD), and it is noted for its protective role in preventing heart failure (HF), obesity, and type-2 diabetes. Furthermore, CD10/substance P interaction has also been shown to contribute to the pain signaling regulation and immunomodulation in diseases such as complex regional pain syndrome (CRPS) and osteoarthritis (OA). The emergence of COVID-19 has sparked interest in CD10's involvement in the disease's pathogenesis. Given its association with multiple disease states, CD10 is a prime therapeutic target; inhibitors targeting CD10 are now being advanced as therapeutic agents. This review compiles recent and earlier literature on CD10, elucidating its physicochemical attributes, tissue-specific expression, and molecular functions. Furthermore, it details the association of CD10 with various diseases and the clinical advancements of its inhibitors, providing a comprehensive overview of its growing significance in medical research.

Potential confounders of the obesity paradox in older patients following transcatheter aortic valve replacement

PURPOSE

A higher body mass index (BMI) is associated with lower mortality in older patients following transcatheter aortic valve replacement (TAVR) for severe aortic valve stenosis. The current study aimed to investigate potential confounders of association between BMI and prognosis.

METHODS

The retrospective single-center study included consecutive patients following TAVR and excluded those in whom subcutaneous fat accumulation (SFA), visceral fat accumulation (VFA), and major psoas muscle (MPM) volume were not assessed by computed tomography. Cachexia was defined as a combination of BMI < 20 kg/m2 and any biochemical abnormalities.

RESULTS

After 2 patients were excluded, 234 (age, 86 ± 5 years; male, 77 [33%]; BMI, 22.4 ± 3.8 kg/m2; SFA, 109 (54-156) cm2; VFA, 71 (35-115) cm2; MPM, 202 (161-267) cm3; cachexia, 49 [21%]) were evaluated. SFA and VFA were strongly correlated with BMI (ρ = 0.734 and ρ = 0.712, respectively), whereas MPM was weakly correlated (ρ = 0.346). Two-year all-cause mortality was observed in 31 patients (13%). Higher BMI was associated with lower mortality (adjusted hazard ratio [aHR], 0.86; 95% confidence interval [CI], 0.77-0.95). A similar result was observed in the multivariate model including SFA (aHR in an increase of 20 cm2, 0.87; 95% CI, 0.77-0.98) instead of BMI, whereas VFA was not significant. Cachexia was a worse predictor (aHR, 2.51; 95% CI 1.11-5.65).

CONCLUSIONS

Association of higher BMI with lower mortality may be confounded by SFA in older patients following TAVR. Cachexia might reflect higher mortality in patients with lower BMI.

Aging adipose tissue, insulin resistance, and type 2 diabetes

With the increase of population aging, the prevalence of type 2 diabetes (T2D) is also rising. Aging affects the tissues and organs of the whole body, which is the result of various physiological and pathological processes. Adipose tissue has a high degree of plasticity and changes with aging. Aging changes the distribution of adipose tissue, affects adipogenesis, browning characteristics, inflammatory status and adipokine secretion, and increases lipotoxicity. These age-dependent changes in adipose tissue are an important cause of insulin resistance and T2D. Understanding adipose tissue changes can help promote healthy aging process. This review summarizes changes in adipose tissue ascribable to aging, with a focus on the role of aging adipose tissue in insulin resistance and T2D.

Association between visceral adiposity and generalized anxiety disorder (GAD)

BACKGROUND AND OBJECTIVES

Due to an increased rate of inflammation in generalized anxiety disorder (GAD), insight into the mediating factors in the onset and recurrence of the inflammatory response can help to achieve novel treatments for alleviating the risk of GAD. In the current study, we aimed to evaluate the possible relationship between visceral adipose tissue (VAT) as an important intermediary in inflammation pathways and GAD in participants of the Employees' Health Cohort Study of Iran (EHCSIR).

METHOD

We analyzed the data from 3889 included participants aged > 18 years in the EHCSIR study, which were collected from 2017 to 2020. Lifetime and 12-month GAD were assessed using the Composite International Diagnostic Interview (CIDI-2.1) questionnaire. The adjusted prevalence ratio was computed to evaluate the association between GAD and visceral adiposity index (VAI), GAD and visceral fat area (VFA), GAD and body mass index (BMI) and ultimately GAD and waist circumference (WC) in males and females using STATA software.

RESULTS

Log-binomial analysis showed a higher prevalence ratio of 12-month GAD associated with VFA in women [PR: 1.42, CI: 1.07-1.87, P: 0.015]. The prevalence of lifetime GAD was higher in obese women (BM1 > 30) [PR: 2.35, CI: 1.07-5.13, P:0.03] than in women with normal BMI. Women with higher VAI were also significantly more likely to suffer lifetime GAD [PR: 1.25, CI: 1.05]. 1.48, P:0.01]. In males, the prevalence of lifetime diagnosed GAD per 1 standard deviation increase in VFA was 0.65 [CI: 0.46-0.91, P: 0.01].

CONCLUSION

Visceral adiposity as a positive agent was associated with GAD prevalence in women. The presence of GAD symptoms showed no relationship to VFA in men.

Subcutaneous white adipose tissue independently regulates burn-induced hypermetabolism via immune-adipose crosstalk

Severe burns induce a chronic hypermetabolic state that persists well past wound closure, indicating that additional internal mechanisms must be involved. Adipose tissue is suggested to be a central regulator in perpetuating hypermetabolism, although this has not been directly tested. Here, we show that thermogenic adipose tissues are activated in parallel to increases in hypermetabolism independent of cold stress. Using an adipose tissue transplantation model, we discover that burn-derived subcutaneous white adipose tissue alone is sufficient to invoke a hypermetabolic response in a healthy recipient mouse. Concomitantly, transplantation of healthy adipose tissue alleviates metabolic dysfunction in a burn recipient. We further show that the nicotinic acetylcholine receptor signaling pathway may mediate an immune-adipose crosstalk to regulate adipose tissue remodeling post-injury. Targeting this pathway could lead to innovative therapeutic interventions to counteract hypermetabolic pathologies.

Impact of Protease Inhibitor-Based Highly Active Antiretroviral Therapy on Fetal Subcutaneous Fat Tissue in HIV-Pregnant Women in a Middle-Income Country

BACKGROUND

HIV infection continues to be a global public health challenge, affecting approximately 1.7 million reproductive-aged women. Protease inhibitor-based highly active antiretroviral therapy (PI-HAART) has significantly reduced the risk of vertical transmission of HIV from mother to child. Nevertheless, concerns linger regarding the long-term effects, particularly on body composition, notably subcutaneous fat tissue (SFT). Although HIV-associated lipodystrophy syndrome (LS) has been well documented in adults and older children, its impact on fetuses exposed to PI-HAART remains underexplored. This study aims to evaluate SFT in the fetuses of HIV-pregnant women exposed to PI-HAART, assessing the potential clinical implications.

METHODS

We conducted a comparative study between HIV-pregnant women receiving PI-HAART and an HIV-negative control group. Fetometry measurements were obtained via 3D ultrasound. SFT in the fetal arm and thigh segments was assessed. Data were analyzed using lineal multivariate regression and receiver-operating characteristics (ROC)-curve analysis.

RESULTS

Fetuses exposed to PI-HAART exhibited a significant reduction in subcutaneous fat, particularly in the proximal third-middle union of the femur (coefficient: -2.588, p = 0.042). This reduction was correlated with lower newborn serum glucose levels (65.7 vs. 56.1, p = 0.007; coefficient: -1.277, p = 0.045).

CONCLUSIONS

Our study sheds light on the connection between PI-HAART, fetal subcutaneous fat, and neonatal health. These findings might reveal the long-lasting effects of PI-HAART on newborns and children's well-being. Our results emphasize the need for a more balanced approach to managing pregnant women with HIV in developing countries and open new venues for research on the impact of intrauterine PI-HAART exposure on energy metabolism and fetal programming.

Neurosecretory Protein GM-Expressing Neurons Participate in Lipid Storage and Inflammation in Newly Developed Cre Driver Male Mice

Obesity induces inflammation in the hypothalamus and adipose tissue, resulting in metabolic disorders. A novel hypothalamic neuropeptide, neurosecretory protein GM (NPGM), was previously identified in the hypothalamus of vertebrates. While NPGM plays an important role in lipid metabolism in chicks, its metabolic regulatory effects in mammals remain unclear. In this study, a novel Cre driver line, NPGM-Cre, was generated for cell-specific manipulation. Cre-dependent overexpression of Npgm led to fat accumulation without increased food consumption in male NPGM-Cre mice. Chemogenetic activation of NPGM neurons in the hypothalamus acutely promoted feeding behavior and chronically resulted in a transient increase in body mass gain. Furthermore, the ablated NPGM neurons exhibited a tendency to be glucose intolerant, with infiltration of proinflammatory macrophages into the adipose tissue. These results suggest that NPGM neurons may regulate lipid storage and inflammatory responses, thereby maintaining glucose homeostasis.

Rosiglitazone-induced PPARγ activation promotes intramuscular adipocyte adipogenesis of pig

Intramuscular fat (IMF) positively influences various aspects of meat quality, while the subcutaneous fat (SF) has negative effect on carcass characteristics and fattening efficiency. Peroxisome proliferator-activated receptor gamma (PPARγ) is a key regulator of adipocyte differentiation, herein, through bioinformatic screen for the potential regulators of adipogenesis from two independent microarray datasets, we identified that PPARγ is a potentially regulator between porcine IMF and SF adipogenesis. Then we treated subcutaneous preadipocytes (SA) and intramuscular preadipocytes (IMA) of pig with RSG (1 µmol/L), and we found that RSG treatment promoted the differentiation of IMA via differentially activating PPARγ transcriptional activity. Besides, RSG treatment promoted apoptosis and lipolysis of SA. Meanwhile, by the treatment of conditioned medium, we excluded the possibility of indirect regulation of RSG from myocyte to adipocyte and proposed that AMPK may mediate the RSG-induced differential activation of PPARγ. Collectively, the RSG treatment promotes IMA adipogenesis, and advances SA lipolysis, this effect may be associated with AMPK-mediated PPARγ differential activation. Our data indicates that targeting PPARγ might be an effective strategy to promote intramuscular fat deposition while reduce subcutaneous fat mass of pig.

Association between body composition and the risk of mortality in the obese population in the United States

Background

Recent studies have presented the concept of the obesity paradox, suggesting that individuals with obesity have a lower risk of death than those without obesity. This paradox may arise because body mass index (BMI) alone is insufficient to understand body composition accurately. This study investigated the relationship between fat and muscle mass and the risk of mortality in individuals with overweight/obesity.

Methods

We used data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2006 and 2011 to 2018, which were linked to mortality information obtained from the National Death Index. Multiple Cox regression analyses were performed to estimate mortality risk. Subgroup analysis was conducted using propensity score-matched (PSM) data for age, sex, and race/ethnicity.

Results

This study included 16,555 participants who were overweight/obese (BMI≥25 kg/m2). An increase in appendicular skeletal muscle mass index was associated with a lower mortality risk (hazard ratio [HR]: 0.856; 95% confidence interval [CI]: 0.802-0.915). This finding was consistent with the subgroup analysis of the PSM data. Contrastingly, a high fat mass index was associated with an increased risk of mortality. Sarcopenic overweight/obesity was significantly associated with high mortality compared to obesity without sarcopenia (HR: 1.612, 95%CI: 1.328-1.957). This elevated risk was significant in both age- and sex-based subgroups. This finding was consistent with the subgroup analysis using PSM data.

Conclusion

In contrast to the obesity paradox, a simple increase in BMI does not protect against mortality. Instead, low body fat and high muscle mass reduce mortality risk.

Physical activity, screen time and body composition in 13-year-old adolescents: The Generation R Study

BACKGROUND

Body composition between prepubertal children and adolescents varies, and it is unclear how physical activity and sedentary behaviour affect adolescent body composition.

OBJECTIVES

This study aimed to examine the associations of physical activity and screen time with overall and specific fat depots in the general adolescent population.

METHODS

In a population-based prospective cohort study, among 3258 adolescents aged 13 years, physical activity and screen time were assessed via self-report questionnaires. Body mass index, dual-energy X-ray absorptiometry-based measures (i.e. fat mass and lean body mass) and magnetic resonance imaging-based measures (i.e. abdominal subcutaneous and visceral fat mass) were obtained.

RESULTS

After adjusting for social-demographic and growth-related factors, each additional hour of daily physical activity was associated with lower fat mass, abdominal visceral fat mass and higher lean body mass (all p < 0.05). However, these associations were not observed in the longitudinal analyses. Each additional hour of daily screen time was associated with higher body mass index, fat mass, abdominal subcutaneous and visceral fat mass (all p < 0.05), which were consistent with the longitudinal analyses.

CONCLUSION

Adolescents with higher physical activity and lower screen time had lower levels of adiposity both at the general and visceral levels.

Tissue-specific mechanisms of fat metabolism that focus on insulin actions

BACKGROUND

The accumulation of ectopic fats is related to metabolic syndromes with insulin resistance, which is considered as the first hit in obesity-related diseases. However, systematic understanding of the occurrence of ectopic fats is limited, since organisms are capable of orchestrating complicated intracellular signaling pathways to ensure that the correct nutritional components reach the tissues where they are needed. Interestingly, tissue-specific mechanisms lead to different consequences of fat metabolism with different insulin sensitivities.

AIM OF REVIEW

To summarize the mechanisms of fat deposition in different tissues including adipose tissue, subcutis, liver, muscle and intestines, in an attempt to elucidate interactive mechanisms involving insulin actions and establish a potential reference for the rational uptake of fat.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Tissue-specific fat metabolism serves as a trigger for developing abnormal fat metabolism or as a compensatory agent for regulating normal fat metabolism. Outcomes of de novo lipogenesis and adipogenesis differ in the subcutaneous adipose tissue (SAT), liver and muscle, with the participation of insulin actions. Overload of lipid metabolic capability results in SAT fat expansion, and ectopic fat accumulation implicates impaired lipo-/adipogenesis in SAT. Regulating insulin actions may be a key measure on fat deposition and metabolism in individuals.

Feeding neurons integrate metabolic and reproductive states in mice

Balance between metabolic and reproductive processes is important for survival, particularly in mammals that gestate their young. How the nervous system coordinates this balance is an active area of study. Herein, we demonstrate that somatostatin (SST) neurons of the tuberal hypothalamus alter feeding in a manner sensitive to metabolic and reproductive states in mice. Whereas chemogenetic activation of SST neurons increased food intake across sexes, ablation decreased food intake only in female mice during proestrus. This ablation effect was only apparent in animals with low body mass. Fat transplantation and bioinformatics analysis of SST neuronal transcriptomes revealed white adipose as a key modulator of these effects. These studies indicate that SST hypothalamic neurons integrate metabolic and reproductive cues by responding to varying levels of circulating estrogens to modulate feeding differentially based on energy stores. Thus, gonadal steroid modulation of neuronal circuits can be context dependent and gated by metabolic status.

Dynamic changes in the transcriptome of tRNA-derived small RNAs related with fat metabolism

The prevalence of obesity and overweight is steadily rising, posing a significant global challenge for humanity. The fundamental cause of obesity and overweight lies in the abnormal accumulation of adipose tissue. While numerous regulatory factors related to fat deposition have been identified in previous studies, a considerable number of regulatory mechanisms remain unknown. tRNA-derived small RNAs (tsRNAs), a novel class of non-coding RNAs, have emerged as significant regulators in various biological processes. In this study, we obtained small RNA sequencing data from subcutaneous white adipose tissue and omental white adipose tissue of lean and obese pigs. In addition, we similarly obtained tsRNAs profiles from scapular brown adipose tissue (BAT), inguinal white adipose tissue (iWAT) and epigonadal white adipose tissue (eWAT) of normal mice. Finally, we successfully identified a large number of expressed tsRNAs in each tissue type and identified tsRNAs conserved in different adipose tissues of pigs and mice. These datasets will be a valuable resource for elucidating the epigenetic mechanisms of fat deposition.

Adipose distribution patterns as prognostic factors in patients with HCC: A systematic review and meta-analysis

PURPOSES

The present meta-analysis aimed at identifying potential prognostic indicators associated with adipose distribution patterns for predicting the survival outcomes of patients diagnosed with hepatocellular carcinoma (HCC).

METHODS

A systematic retrieve was performed to identify studies investigating the association of adipose distribution patterns and the prognosis of HCC from the inception of PubMed, Embase, Cochrane Library, and Web of Science databases to May 25, 2023. The Newcastle-Ottawa scale was applied to assess the quality of included studies. The hazard ratios (HRs) and 95 % confidence intervals (CIs) of adipose distribution parameters of visceral, subcutaneous, and intermuscular adipose tissue were extracted. Univariate and multivariable meta-analyses were performed by Stata 12.0 to evaluate the relationship between these factors and overall survival (OS) and recurrence-free survival (RFS).

RESULTS

A total of 31 studies, comprising 7021 patients, including 2456 patients with HCV and 1466 patients with HBV were included. The pooled results indicated that only high visceral to subcutaneous adipose area ratio (VSR) (univariate analysis of OS: HR = 1.42, 95 % CI = 1.28-1.58, P < 0.001; multivariate analysis of OS: HR = 1.45, 95 % CI = 1.27-1.65, P < 0.001; univariate analysis of RFS: HR = 1.30, 95 % CI = 1.08-1.56, P = 0.006; multivariate analysis of RFS: HR = 1.36, 95 % CI = 1.10-1.67, P = 0.004) was both related to worse OS and RFS, with no significant heterogeneity observed.

CONCLUSION

Pretreatment VSR, as the sole parameter among adipose distribution-related factors exhibiting independent and stable associations with OS and RFS in patients with HCC, may hold promise as a potential prognostic factor for HCC.

Progression to Obesity: Variations in Patterns of Metabolic Fluxes, Fat Accumulation, and Gastrointestinal Responses

Obesity is a multifactorial disorder that is remarkably heterogeneous. It presents itself in a variety of phenotypes that can be metabolically unhealthy or healthy, associate with no or multiple metabolic risk factors, gain extreme body weight (super-responders), as well as resist obesity despite the obesogenic environment (non-responders). Progression to obesity is ultimately linked to the overall net energy balance and activity of different metabolic fluxes. This is particularly evident from variations in fatty acids oxidation, metabolic fluxes through the pyruvate-phosphoenolpyruvate-oxaloacetate node, and extracellular accumulation of Krebs cycle metabolites, such as citrate. Patterns of fat accumulation with a focus on visceral and ectopic adipose tissue, microbiome composition, and the immune status of the gastrointestinal tract have emerged as the most promising targets that allow personalization of obesity and warrant further investigations into the critical issue of a wider and long-term weight control. Advances in understanding the biochemistry mechanisms underlying the heterogenous obesity phenotypes are critical to the development of targeted strategies to maintain healthy weight.

Amino acids contribute to adaptive thermogenesis. New insights into the mechanisms of action of recent drugs for metabolic disorders are emerging

Adaptive thermogenesis is the heat production by muscle contractions (shivering thermogenesis) or brown adipose tissue (BAT) and beige fat (non-shivering thermogenesis) in response to external stimuli, including cold exposure. BAT and beige fat communicate with peripheral organs and the brain through a variegate secretory and absorption processes - controlling adipokines, microRNAs, extracellular vesicles, and metabolites - and have received much attention as potential therapeutic targets for managing obesity-related disorders. The sympathetic nervous system and norepinephrine-releasing adipose tissue macrophages (ATM) activate uncoupling protein 1 (UCP1), expressed explicitly in brown and beige adipocytes, dissolving the electrochemical gradient and uncoupling tricarboxylic acid cycle and the electron transport chain from ATP production. Mounting evidence has attracted attention to the multiple effects of dietary and endogenously synthesised amino acids in BAT thermogenesis and metabolic phenotype in animals and humans. However, the mechanisms implicated in these processes have yet to be conclusively characterized. In the present review article, we aim to define the principal investigation areas in this context, including intestinal microbiota constitution, adipose autophagy modulation, and secretome and metabolic fluxes control, which lead to increased brown/beige thermogenesis. Finally, also based on our recent epicardial adipose tissue results, we summarise the evidence supporting the notion that the new dual and triple agonists of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and glucagon (GCG) receptor - with never before seen weight loss and insulin-sensitizing efficacy - promote thermogenic-like amino acid profiles in BAT with robust heat production and likely trigger sympathetic activation and adaptive thermogenesis by controlling amino acid metabolism and ATM expansion in BAT and beige fat.

Subcutaneous adipose tissue alteration in aging process associated with thyroid hormone signaling

BACKGROUND

Functional changes in subcutaneous adipose tissue (SAT) occur earlier in the aging process and play an important role in the occurrence and development of age-related metabolic diseases. The mechanism of this phenomenon is still unclear, and the change in adipose tissue with age is poorly understood.

METHODS

We used transcriptome sequencing (RNA seq) to screen differentially expressed genes at the mRNA level, and analyzed the functional characteristics of the differential genes through GO and KEGG analysis in human SAT of all ages. In order to clarify the specific mechanism of the functional change, we analyzed the chromatin accessibility in the promoter region in the same SAT used in the RNA seq by the assay for transposase-accessible chromatin with high throughput sequencing (ATAC-seq) and obtained the functional genes in SAT changed with age. To verify these changes, we enlarged our sample content of human SAT. The primary mice adipocytes were extracted and stimulated by thyroid hormone of different concentration to construct an animal model, and the expression of the genes were determined through real-time Polymerase Chain Reaction(RT-PCR). The oxygen consumption test and immunofluorescence staining were used to determine the mitochondrial function of SAT.

RESULTS

RNA-seq showed characteristic gene expression of young and old human SAT, in which 331 genes were up-regulated and 349 genes were down-regulated. ATAC-seq, RNA-seq, combined with the mouse prediction model, determined the functional changed characteristics of seven genes. All these genes expressed differently in SAT of different ages, in which, NCF1, NLRP3, DUOX1 showed positive correlation with age; The expression of IFI30, P2RX1, P2RX6, PRODH, however, decreased with age. And all these genes showed dose dependent alternations under treatment of triiodothyroxine in mice SAT. The oxygen consumption rate revealed significant changes of the mitochondrial function and ROS accumulation in human SAT of different ages.

CONCLUSION

In elderly individuals, the function, in addition to distribution, of SAT undergoes significant changes, primarily in mitochondria, which may be due to insensitivity to thyroid hormone signaling. These results identified seven novel genes regulated by thyroid hormone, exhibiting significant changes in SAT of different age, and are probably related to the dysfunction of the aged SAT due to the mitochondrial damage and ROS accumulation.

Computed tomographic abdominal fat volume estimation - a handy tool to predict the risk of metabolic syndrome

Purpose

Abdominal obesity plays a significant role in the development of metabolic syndrome, with individual metabolic risk profiles for visceral and subcutaneous adipose tissues. This study aimed to calculate and correlate the subcutaneous, visceral, and total fat compartment volume in metabolic and non-metabolic syndrome patients.

Material and methods

This was a cross-sectional study conducted on 112 patients categorized into Group A (with metabolic syndrome) and Group B (without metabolic syndrome). They were subjected to computed tomography (CT) study of the abdomen using a 128-slice MDCT scanner. Body mass index (BMI), visceral fat volume (VFV), subcutaneous fat volume (SFV), and total fat volume (TFV) were calculated and correlated with biochemical evidence of metabolic syndrome.

Results

The mean age of patients in Group A was 60.91 ± 12.23 years as compared to Group B, which was 50.12 ± 16.30 years. Overall, a male predominance was observed, i.e. 69 cases (61.6%). BMI was proven to be an inaccurate risk predictor. However, mean VFV, SFV, and TFV was statistically higher in patients with metabolic syndrome (p = 0.001), with visceral fat volume predicting a higher risk in females (p = 0.026).

Conclusions

Abdominal CT is a commonly performed yet unexplored tool for the risk assessment of metabolic syndrome. Through the results obtained in this study, we have proven the need for calculating SFV, VFV, and TFV as predictors of metabolic syndrome in comparison to the conventional practice of BMI assessment. The radiologist can thus work with the clinician to effectively detect and treat this health condition.

Risk Factors of Non-alcoholic Fatty Liver Disease in the Iranian Adult Population: A Systematic Review and Meta-analysis

Context: Non-alcoholic fatty liver disease (NAFLD) is progressing considerably worldwide. Identifying the risk factors of NAFLD is a critical step in preventing its progression. Methods: In November 2022, two independent researchers studied seven databases, including PubMed, ISI/WoS, ProQuest, Scopus, SID, Magiran, and Google Scholar, and reference list of relevant articles, searching studies that assessed NAFLD risk factors in the Iranian adult population. Heterogeneity between studies was assessed by Cochran’s test and its composition using I2 statistics. A random-effects model was used when heterogeneity was observed; otherwise, a fixed-effects model was applied. Egger’s regression test and Trim-and-Fill analysis were used to assess publication bias. Comprehensive Meta-analysis software (version 3) was used for the analyses of the present study. Results: The results of this study showed significant associations between NAFLD with age [n = 15, odds ratio (OR) = 2.12, 95% CI: 1.79 - 2.51], body mass index (n = 46, OR = 5.00, 95% CI: 3.34 - 7.49), waist circumference (n = 20, OR = 6.37, 95% CI: 3.25 - 12.48), waist-to-hip ratio (n = 17, OR = 4.72, 95% CI: 3.93 - 5.66), total cholesterol (n = 39, OR = 1.80, 95% CI: 1.52 - 2.13), high-density lipoprotein (n = 37, OR = 0.53, 95% CI: 0.44 - 0.65), low-density lipoprotein (n = 31, OR = 1.68, 95% CI: 1.38 - 2.05), triglyceride (n = 31, OR = 3.21, 95% CI: 2.67 - 3.87), alanine aminotransferase (n = 26, OR = 4.06, 95% CI: 2.94 - 5.62), aspartate aminotransferase (n = 27, OR = 2.16, 95% CI: 1.50 - 3.12), hypertension (n = 13, OR = 2.53, 95% CI: 2.32 - 2.77), systolic blood pressure (n = 13, OR = 1.83, 95% CI: 1.53 - 2.18), diastolic blood pressure (n = 14, OR = 1.80, 95% CI: 1.48 - 2.20), fasting blood sugar (n = 31,OR = 2.91, 95% CI: 2.11- 4.01), homeostatic model assessment for insulin resistance (n = 5, OR = 1.92, 95% CI: 1.48 - 2.59), diabetes mellitus (n = 15, OR = 3.04, 95% CI: 2.46 - 3.75), metabolic syndrome (n = 10, OR = 3.56, 95% CI: 2.79 - 4.55), and physical activity (n = 11, OR = 0.32, 95% CI: 0.24 - 0.43) (P < 0.05). Conclusions: In conclusion, several factors are significantly associated with NAFLD. However, anthropometric indices had the strongest relationship with NAFLD in the Iranian adult population.

Sarcopenia negatively affects postoperative short-term outcomes of patients with non-cirrhosis liver cancer

BACKGROUND

Literature review have shown that sarcopenia substantially alters the postoperative outcomes after liver resection for malignant tumors. However, these retrospective studies do not distinguish cirrhotic and non-cirrhotic liver cancer patients, nor combine the assessment of muscle strength in addition to muscle mass. The purpose of this study is to study the relationship between sarcopenia and short-term outcomes after hepatectomy in patients with non-cirrhotic liver cancer.

METHODS

From December 2020 to October 2021, 431 consecutive inpatients were prospectively enrolled in this study. Muscle strength and mass were assessed by handgrip strength and the skeletal muscle index (SMI) on preoperative computed tomographic scans, respectively. Based on the SMI and the handgrip strength, patients were divided into four groups: group A (low muscle mass and strength), group B (low muscle mass and normal muscle strength), group C (low muscle strength and normal muscle mass), and group D (normal muscle mass and strength). The main outcome was major complications and the secondary outcome was 90-d Readmission rate.

RESULTS

After strictly exclusion, 171 non-cirrhosis patients (median age, 59.00 [IQR, 50.00-67.00] years; 72 females [42.1%]) were selected in the final analysis. Patients in group A had a statistically significantly higher incidence of major postoperative complications (Clavien-Dindo classification ≥ III) (26.1%, p = 0.032), blood transfusion rate (65.2%, p < 0.001), 90-day readmission rate (21.7%, p = 0.037) and hospitalization expenses (60,842.00 [IQR, 35,563.10-87,575.30], p < 0.001) than other groups. Sarcopenia (hazard ratio, 4.21; 95% CI, 1.44-9.48; p = 0.025) and open approach (hazard ratio, 2.56; 95% CI, 1.01-6.49; p = 0.004) were independent risk factors associated with major postoperative complications.

CONCLUSIONS

Sarcopenia is closely related to poor short-term postoperative outcomes in non-cirrhosis liver cancer patients and the assessment that combines muscle strength and muscle mass can simply and comprehensively identify it.

TRIAL REGISTRATION

ClinicalTrials.gov identifiers NCT04637048 . (19/11/2020).

Beyond energy balance regulation: The underestimated role of adipose tissues in host defense against pathogens

Although the adipose tissue (AT) is a central metabolic organ in the regulation of whole-body energy homeostasis, it is also an important endocrine and immunological organ. As an endocrine organ, AT secretes a variety of bioactive peptides known as adipokines - some of which have inflammatory and immunoregulatory properties. As an immunological organ, AT contains a broad spectrum of innate and adaptive immune cells that have mostly been studied in the context of obesity. However, overwhelming evidence supports the notion that AT is a genuine immunological effector site, which contains all cell subsets required to induce and generate specific and effective immune responses against pathogens. Indeed, AT was reported to be an immune reservoir in the host's response to infection, and a site of parasitic, bacterial and viral infections. In addition, besides AT's immune cells, preadipocytes and adipocytes were shown to express innate immune receptors, and adipocytes were reported as antigen-presenting cells to regulate T-cell-mediated adaptive immunity. Here we review the current knowledge on the role of AT and AT's immune system in host defense against pathogens. First, we will summarize the main characteristics of AT: type, distribution, function, and extraordinary plasticity. Second, we will describe the intimate contact AT has with lymph nodes and vessels, and AT immune cell composition. Finally, we will present a comprehensive and up-to-date overview of the current research on the contribution of AT to host defense against pathogens, including the respiratory viruses influenza and SARS-CoV-2.

Fat Loss in Patients with Metastatic Clear Cell Renal Cell Carcinoma Treated with Immune Checkpoint Inhibitors

The purpose of this study was to determine the prognostic impact of fat loss after immune checkpoint inhibitor (ICI) treatment in patients with metastatic clear cell renal cell carcinoma (ccRCC). Data from 60 patients treated with ICI therapy for metastatic ccRCC were retrospectively analyzed. Changes in cross-sectional areas of subcutaneous fat (SF) between the pre-treatment and post-treatment abdominal computed tomography (CT) images were expressed as percentages and were divided by the interval between the CT scans to calculate ΔSF (%/month). SF loss was defined as ΔSF < -5%/month. Survival analyses for overall survival (OS) and progression-free survival (PFS) were performed. Patients with SF loss had shorter OS (median, 9.5 months vs. not reached; p < 0.001) and PFS (median, 2.6 months vs. 33.5 months; p < 0.001) than patients without SF loss. ΔSF was independently associated with OS (adjusted hazard ratio (HR), 1.49; 95% confidence interval (CI), 1.07-2.07; p = 0.020) and PFS (adjusted HR, 1.57; 95% CI, 1.17-2.12; p = 0.003), with a 5%/month decrease in SF increasing the risk of death and progression by 49% and 57%, respectively. In conclusion, Loss of SF after treatment initiation is a significant and independent poor prognostic factor for OS and PFS in patients with metastatic ccRCC who receive ICI therapy.

Inguinal Fat Compensates Whole Body Metabolic Functionality in Partially Lipodystrophic Mice with Reduced PPARγ Expression

Peroxisome proliferator-activated receptor γ (PPARγ) gene mutations in humans and mice lead to whole-body insulin resistance and partial lipodystrophy. It is unclear whether preserved fat depots in partial lipodystrophy are beneficial for whole-body metabolic homeostasis. We analyzed the insulin response and expression of metabolic genes in the preserved fat depots of PpargC/- mice, a familial partial lipodystrophy type 3 (FPLD3) mouse model resulting from a 75% decrease in Pparg transcripts. Perigonadal fat of PpargC/- mice in the basal state showed dramatic decreases in adipose tissue mass and insulin sensitivity, whereas inguinal fat showed compensatory increases. Preservation of inguinal fat metabolic ability and flexibility was reflected by the normal expression of metabolic genes in the basal or fasting/refeeding states. The high nutrient load further increased insulin sensitivity in inguinal fat, but the expression of metabolic genes became dysregulated. Inguinal fat removal resulted in further impairment of whole-body insulin sensitivity in PpargC/- mice. Conversely, the compensatory increase in insulin sensitivity of the inguinal fat in PpargC/- mice diminished as activation of PPARγ by its agonists restored insulin sensitivity and metabolic ability of perigonadal fat. Together, we demonstrated that inguinal fat of PpargC/- mice plays a compensatory role in combating perigonadal fat abnormalities.

Maternal obesity and programming of metabolic syndrome in the offspring: searching for mechanisms in the adipocyte progenitor pool

BACKGROUND

It is now understood that it is the quality rather than the absolute amount of adipose tissue that confers risk for obesity-associated disease. Adipose-derived stem cells give rise to adipocytes during the developmental establishment of adipose depots. In adult depots, a reservoir of progenitors serves to replace adipocytes that have reached their lifespan and for recruitment to increase lipid buffering capacity under conditions of positive energy balance. MAIN: The adipose tissue expandability hypothesis posits that a failure in de novo differentiation of adipocytes limits lipid storage capacity and leads to spillover of lipids into the circulation, precipitating the onset of obesity-associated disease. Since adipose progenitors are specified to their fate during late fetal life, perturbations in the intrauterine environment may influence the rapid expansion of adipose depots that occurs in childhood or progenitor function in established adult depots. Neonates born to mothers with obesity or diabetes during pregnancy tend to have excessive adiposity at birth and are at increased risk for childhood adiposity and cardiometabolic disease.

CONCLUSION

In this narrative review, we synthesize current knowledge in the fields of obesity and developmental biology together with literature from the field of the developmental origins of health and disease (DOHaD) to put forth the hypothesis that the intrauterine milieu of pregnancies complicated by maternal metabolic disease disturbs adipogenesis in the fetus, thereby accelerating the trajectory of adipose expansion in early postnatal life and predisposing to impaired adipose plasticity.

An adipocentric perspective on the development and progression of non-alcoholic fatty liver disease

Alongside the liver, white adipose tissue (WAT) is critical in regulating systemic energy homeostasis. Although each organ has its specialised functions, they must work coordinately to regulate whole-body metabolism. Adipose tissues and the liver are relatively resilient and can adapt to an energy surplus by facilitating triglyceride (TG) storage up to a certain threshold level without significant metabolic disturbances. However, lipid storage in WAT beyond a "personalised" adiposity threshold becomes dysfunctional, leading to metabolic inflexibility, progressive inflammation, and aberrant adipokine secretion. Moreover, the failure of adipose tissue to store and mobilise lipids results in systemic knock-on lipid overload, particularly in the liver. Factors contributing to hepatic lipid overload include lipids released from WAT, dietary fat intake, and enhanced de novo lipogenesis. In contrast, extrahepatic mechanisms counteracting toxic hepatic lipid overload entail coordinated compensation through oxidation of surplus fatty acids in brown adipose tissue and storage of fatty acids as TGs in WAT. Failure of these integrated homeostatic mechanisms leads to quantitative increases and qualitative alterations to the lipidome of the liver. Initially, hepatocytes preferentially accumulate TG species leading to a relatively "benign" non-alcoholic fatty liver. However, with time, inflammatory responses ensue, progressing into more severe conditions such as non-alcoholic steatohepatitis, cirrhosis, and hepatocellular carcinoma, in some individuals (often without an early prognostic clue). Herein, we highlight the pathogenic importance of obesity-induced "adipose tissue failure", resulting in decreased adipose tissue functionality (i.e. fat storage capacity and metabolic flexibility), in the development and progression of NAFL/NASH.

Metabolic crosstalk between thermogenic adipocyte and cancer cell: Dysfunction and therapeutics

As one of the largest endocrine organs with a wide distribution in organisms, adipose tissue secretes multiple adipokines, cytokines, metabolites, and exosomes to promote tumour development. Elaborating the crosstalk between cancer cells and adipocytes provides a tissue-level perspective of cancer progression, which reflects the heterogeneity and complexity of human tumours. Three main types of adipose tissues, white, brown, and beige adipose tissue, have been described. Thermogenic capacity is a prominent characteristic of brown and beige adipocytes. Most studies so far mainly focus on the contribution of white adipocytes to the tumour microenvironment. However, the role of thermogenic adipose tissue in malignant cancer behaviour has been largely overlooked. Recently, emerging evidence suggests that beige/brown adipocytes play a key role in the development and progression of various cancers. This review focuses on the bidirectional communication between tumour cells and thermogenic adipocytes and the therapeutic strategies to disrupt this interaction.

U-shaped relationship between subcutaneous adipose tissue index and mortality in liver cirrhosis

BACKGROUND

Subcutaneous and visceral adipose tissues are important body components, but their effects on the mortality in patients with liver cirrhosis remain controversial based on the current evidence.

METHODS

We retrospectively identified 372 eligible patients in whom subcutaneous adipose tissue index (SATI) and visceral adipose tissue index (VATI) could be measured by computed tomography images at the third lumbar vertebra. The association of SATI and VATI with the risk of death was evaluated on a continuous scale with restricted cubic spline curves based on Cox proportional hazards models. Cumulative probability of mortality was estimated by Nelson-Aalen cumulative risk curve analyses. Independent predictors of death were evaluated by competing risk analyses after adjusting for age, sex, and model for end-stage liver disease score.

RESULTS

Majority of patients were male (69.4%) with a mean age of 55.40 ± 10.68 years. SATI had a U-shaped association with mortality (P for non-linearity <0.001). Cutoff values of SATI were 19.7 and 51.8 cm² /m² at the points where hazard ratios were just <1.2. SATI was categorized as low (<19.7 cm² /m² ), moderate (19.7-51.8 cm² /m² ), and high (>51.8 cm² /m² ) level. There was no significant difference in the cumulative probability of mortality between low versus moderate SATI groups (Gray's test, P = 0.052) and high versus moderate SATI groups (Gray's test, P = 0.054). Competing risk analyses demonstrated that low SATI could increase the mortality compared with moderate SATI (subdistribution hazard ratio [sHR] = 1.66, 95% confidence interval [CI]: 0.992-2.78, P = 0.054) and was an independent predictor of death (sHR = 1.86, 95% CI: 1.059-3.28, P = 0.031). Competing risk analyses also demonstrated that high SATI could significantly increase the mortality compared with moderate SATI (sHR = 1.6, 95% CI: 1-2.54, P = 0.049), and was an independent predictor of death (sHR = 2.007, 95% CI: 1.195-3.37, P = 0.0085). VATI had an irregularly shaped association with mortality (P for non-linearity <0.001). Cutoff values of VATI were 9.8 and 40.2 cm² /m² at the points where hazard ratios were just <1.2. VATI was categorized as low (<9.8 cm² /m² ), moderate (9.8-40.2 cm² /m² ), and high (>40.2 cm² /m² ) level. There was no significant difference in the cumulative probability of mortality between low versus moderate VATI groups (Gray's test, P = 0.381) and high versus moderate VATI groups (Gray's test, P = 0.787). Competing risk analyses demonstrated that neither low (sHR = 1.27, 95% CI: 0.599-2.7, P = 0.53) nor high VATI (sHR = 0.848, 95% CI: 0.539-1.34, P = 0.48) was an independent predictor of death compared with moderate VATI.

CONCLUSIONS

Both excessive deficiency and accumulation of subcutaneous adipose tissues negatively influence the outcomes of cirrhotic patients.

SARS-CoV-2 infection induces persistent adipose tissue damage in aged golden Syrian hamsters

Coronavirus disease 2019 (COVID-19, caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2)) is primarily a respiratory illness. However, various extrapulmonary manifestations have been reported in patients with severe forms of COVID-19. Notably, SARS-CoV-2 was shown to directly trigger white adipose tissue (WAT) dysfunction, which in turn drives insulin resistance, dyslipidemia, and other adverse outcomes in patients with COVID-19. Although advanced age is the greatest risk factor for COVID-19 severity, published data on the impact of SARS-CoV-2 infection on WAT in aged individuals are scarce. Here, we characterized the response of subcutaneous and visceral WAT depots to SARS-CoV-2 infection in young adult and aged golden hamsters. In both age groups, infection was associated with a decrease in adipocyte size in the two WAT depots; this effect was partly due to changes in tissue's lipid metabolism and persisted for longer in aged hamsters than in young-adult hamsters. In contrast, only the subcutaneous WAT depot contained crown-like structures (CLSs) in which dead adipocytes were surrounded by SARS-CoV-2-infected macrophages, some of them forming syncytial multinucleated cells. Importantly, older age predisposed to a unique manifestation of viral disease in the subcutaneous WAT depot during SARS-CoV-2 infection; the persistence of very large CLSs was indicative of an age-associated defect in the clearance of dead adipocytes by macrophages. Moreover, we uncovered age-related differences in plasma lipid profiles during SARS-CoV-2 infection. These data suggest that the WAT's abnormal response to SARS-CoV-2 infection may contribute to the greater severity of COVID-19 observed in elderly patients.

Feeding Neurons Integrate Metabolic and Reproductive States in Mice

Trade-offs between metabolic and reproductive processes are important for survival, particularly in mammals that gestate their young. Puberty and reproduction, as energetically taxing life stages, are often gated by metabolic availability in animals with ovaries. How the nervous system coordinates these trade-offs is an active area of study. We identify somatostatin neurons of the tuberal nucleus (TNSST) as a node of the feeding circuit that alters feeding in a manner sensitive to metabolic and reproductive states in mice. Whereas chemogenetic activation of TNSST neurons increased food intake across sexes, selective ablation decreased food intake only in female mice during proestrus. Interestingly, this ablation effect was only apparent in animals with a low body mass. Fat transplantation and bioinformatics analysis of TNSST neuronal transcriptomes revealed white adipose as a key modulator of the effects of TNSST neurons on food intake. Together, these studies point to a mechanism whereby TNSST hypothalamic neurons modulate feeding by responding to varying levels of circulating estrogens differentially based on energy stores. This research provides insight into how neural circuits integrate reproductive and metabolic signals, and illustrates how gonadal steroid modulation of neuronal circuits can be context-dependent and gated by metabolic status.

Mechanic Insight into the Distinct and Common Roles of Ovariectomy Versus Adrenalectomy on Adipose Tissue Remodeling in Female Mice

Dysfunctions of the ovaries and adrenal glands are both evidenced to cause aberrant adipose tissue (AT) remodeling and resultant metabolic disorders, but their distinct and common roles are poorly understood. In this study, through biochemical, histological and RNA-seq analyses, we comprehensively explored the mechanisms underpinning subcutaneous (SAT) and visceral adipose tissue (VAT) remodeling, in response to ovariectomy (OVX) versus adrenalectomy (ADX) in female mice. OVX promoted adipocyte differentiation and fat accumulation in both SAT and VAT, by potentiating the Pparg signaling, while ADX universally prevented the cell proliferation and extracellular matrix organization in both SAT and VAT, likely by inactivating the Nr3c1 signaling, thus causing lipoatrophy in females. ADX, but not OVX, exerted great effects on the intrinsic difference between SAT and VAT. Specifically, ADX reversed a large cluster of genes differentially expressed between SAT and VAT, by activating 12 key transcription factors, and thereby caused senescent cell accumulation, massive B cell infiltration and the development of selective inflammatory response in SAT. Commonly, both OVX and ADX enhance circadian rhythmicity in VAT, and impair cell proliferation, neurogenesis, tissue morphogenesis, as well as extracellular matrix organization in SAT, thus causing dysfunction of adipose tissues and concomitant metabolic disorders.

Sex-specific impact of anthropometric parameters on outcomes after transcatheter edge-to-edge repair for secondary mitral regurgitation

BACKGROUND

Body surface area (BSA) has been reported to be the stronger predictor for prognosis than body mass index in heart failure (HF) patients. The sex-specific association of BSA with mortality has been unclear.

METHODS

EuroSMR, a European multicenter registry, included patients who underwent edge-to-edge repair (TEER) for secondary mitral regurgitation (SMR). The outcome was two-year all-cause mortality.

RESULTS

The present cohort included 1594 HF patients (age, 74 ± 10 years; male, 66%). Association of calculated BSA with two-year all-cause mortality was evaluated. Patients were classified into three BSA groups: the lowest 10% (S), the highest 10% (L), and intermediate between S and L (M). Mean BSA was 1.87 ± 0.21 m2 (male, 1.94 ± 0.18 m2; female, 1.73 ± 0.18 m2). The association of BSA with the endpoint in females showed a U-shaped curve, indicating worse prognosis for both S and L. The association in males followed a linear regression, demonstrating better prognosis for L. Hazard ratio (HR) of L to S in males was 0.43 (95% confidence interval [CI], 0.25-0.74; p = 0.002), whereas HR of L to M in females was 1.76 (95% CI, 1.11-2.78; p = 0.016) (p for interaction = 0.003).

CONCLUSIONS

Sex-specific association patterns demonstrate the complex influence of anthropomorphic factors in HF patients scheduled for TEER. Further investigation beyond simple evaluation of weight and height is needed for better comprehension of the obesity paradox and better prediction of the results of transcatheter therapy in HF patients.

Depot-Dependent Impact of Time-Restricted Feeding on Adipose Tissue Metabolism in High Fat Diet-Induced Obese Male Mice

Time-restricted feeding (TRF) is known to be an effective strategy for weight loss and metabolic health. TRF's effect on metabolism is complex and likely acts on various pathways within multiple tissues. Adipose tissue plays a key role in systemic homeostasis of glucose and lipid metabolism. Adipose tissue dysregulation has been causally associated with metabolic disorders in obesity. However, it is largely unknown how TRF impacts metabolic pathways such as lipolysis, lipogenesis, and thermogenesis within different in adipose tissue depots in obesity. To determine this, we conducted a 10-week TRF regimen in male mice, previously on a long-term high fat diet (HFD) and subjected the mice to TRF of a HFD for 10 h per day or ad libitum. The TRF regimen showed reduction in weight gain. TRF restored HFD-induced impairment of adipogenesis and increased lipid storage in white adipose tissues. TRF also showed a depot-dependent effect in lipid metabolism and restored ATP-consuming futile cycle of lipogenesis and lipolysis that is impaired by HFD within epididymal adipose tissue, but not inguinal fat depot. We demonstrate that TRF may be a beneficial option as a dietary and lifestyle intervention in lowering bodyweight and improving adipose tissue metabolism.

CCL17 and CCL22 chemokines are upregulated in human obesity and play a role in vascular dysfunction

Background/Aims

Chemokines are known to play critical roles mediating inflammation in many pathophysiological processes. The aim of this study was to investigate the role of chemokine receptor CCR4 and its ligands CCL17 and CCL22 in human morbid obesity.

Methods

Circulating levels of CCL17 and CCL22 were measured in 60 morbidly obese patients (mean age, 45 ± 1 years; body mass index/BMI, 44 ± 1 kg/m²) who had undergone bariatric bypass surgery, and 20 control subjects. Paired subcutaneous (SCAT) and visceral adipose tissue (VCAT) from patients were analysed to measure expression of CCR4 and its ligands by RT-PCR, western blot and immunohistochemical analysis. The effects of CCR4 neutralization ex vivo on leukocyte-endothelial cells were also evaluated.

Results

Compared with controls, morbidly obese patients presented higher circulating levels of CCL17 (p=0.029) and CCL22 (p<0.001) and this increase was positively correlated with BMI (p=0.013 and p=0.0016), and HOMA-IR Index (p=0.042 and p< 0.001). Upregulation of CCR4, CCL17 and CCL22 expression was detected in VCAT in comparison with SCAT (p<0.05). Using the parallel-plate flow chamber model, blockade of endothelial CCR4 function with the neutralizing antibody anti-CCR4 in morbidly obese patients significantly reduced leucocyte adhesiveness to dysfunctional endothelium, a key event in atherogenesis. Additionally, CCL17 and CCL22 increased activation of the ERK1/2 mitogen-activated protein kinase signalling pathway in human aortic endothelial cells, which was significantly reduced by CCR4 inhibition (p=0.016 and p<0.05).

Conclusion

Based on these findings, pharmacological modulation of the CCR4 axis could represent a new therapeutic approach to prevent adipose tissue dysfunction in obesity.

Association of Metabolically Healthy Obesity and Risk of Cardiovascular Disease Among Adults in China: A Retrospective Cohort Study

PURPOSE

Previous studies have shown that metabolically healthy obesity (MHO) and changes in its status are connected to an increased incidence of cardiovascular disease (CVD). Yet, fewer studies have been conducted in China, especially for the middle-aged and elderly population, a high-risk group. The purpose of the study was to investigate the association between metabolic health status and CVD events.

PATIENTS AND METHODS

A total of 46,055 participants were categorized into 6 subgroups with different metabolic states according to the existence of metabolic syndrome and body mass index (BMI). The changes in obesity and metabolic health status were defined from baseline to follow-up outcomes with a combination of overweight and obesity. Cox proportional hazards models estimated the association of CVD events and each BMI-metabolic groups.

RESULTS

MHO and metabolic abnormality normal weight (MANW) subjects had a higher HR of CVD, 1.62 (95% CI, 1.36-1.92) and 1.24 (95% CI, 1.07-1.44), respectively, than their metabolically healthy normal weight (MHNW) counterparts. Then, more than 50% and 30% of the metabolically healthy overweight or obesity (MHOO) populations maintained their status and converted to a metabolically unhealthy state, respectively. Stable MANW, MHOO and metabolically abnormal obesity (MAO) were associated with a higher risk for CVD, 1.68 (95% CI, 1.37-2.05),1.26 (95% CI, 1.08-1.47) and 1.65 (95% CI, 1.45-1.88), respectively, than stable MHNW.

CONCLUSION

Despite being of normal weight, MANW status is in fact a risk factor for CVD, as well as MHO, especially for the Chinese middle-aged and elderly population. Furthermore, metabolic health is a transient state for partial middle-aged and elderly Chinese individuals, and MAO has the highest risk of CVD, including coronary heart disease (CHD) and stroke.

Metabolic effects of lipectomy and of adipose tissue transplantation

OBJECTIVE

The goal of this study was to review the metabolic effects of fat transplantation.

METHODS

Fat (adipose tissue [AT]) transplantation has been performed extensively for many years in the cosmetic reconstruction industry. However, not all fats are equal. White, brown, and beige AT differ in energy storage and use. Brown and beige AT consume glucose and lipids for thermogenesis and, theoretically, may provide greater metabolic benefit in transplantation. Here, the authors review the metabolic effects of AT transplantation.

RESULTS

Removal of subcutaneous human AT does not have beneficial metabolic effects. Most studies find no benefit from visceral AT transplantation and some studies report harmful effects. In contrast, transplantation of inguinal or subcutaneous AT in mice has positive effects. Brown AT transplant studies have variable results depending on the model but most show benefit.

CONCLUSIONS

Many technical improvements have optimized fat grafting and transplantation in cosmetic surgery. Transplantation of subcutaneous AT has the potential for significant metabolic benefits, although there are few studies in humans or using human AT. Brown AT transplantation is beneficial but not readily feasible in humans thus ex vivo "beiging" may be a useful strategy. AT transplantation may provide clinical benefits in metabolic disorders, especially in the setting of lipodystrophy.

Limosilactobacillus reuteri and caffeoylquinic acid synergistically promote adipose browning and ameliorate obesity-associated disorders

OBJECTIVE

High intake of caffeoylquinic acid (CQA)-rich dietary supplements, such as green coffee bean extracts, offers health-promoting effects on maintaining metabolic homeostasis. Similar to many active herbal ingredients with high pharmacological activities but low bioavailability, CQA has been reported as a promising thermogenic agent with anti-obesity properties, which contrasts with its poor oral absorption. Intestinal tract is the first site of CQA exposure and gut microbes might react quickly to CQA. Thus, it is of interest to explore the role of gut microbiome and microbial metabolites in the beneficial effects of CQA on obesity-related disorders.

RESULTS

Oral CQA supplementation effectively enhanced energy expenditure by activating browning of adipose and thus ameliorated obesity-related metabolic dysfunctions in high fat diet-induced obese (DIO) mice. Here, 16S rRNA gene amplicon sequencing revealed that CQA treatment remodeled the gut microbiota to promote its anti-obesity actions, as confirmed by antibiotic treatment and fecal microbiota transplantation. CQA enriched the gut commensal species Limosilactobacillus reuteri (L. reuteri) and stimulated the production of short-chain fatty acids, especially propionate. Mono-colonization of L. reuteri or low-dose CQA treatment did not reduce adiposity in DIO mice, while their combination elicited an enhanced thermogenic response, indicating the synergistic effects of CQA and L. reuteri on obesity. Exogenous propionate supplementation mimicked the anti-obesity effects of CQA alone or when combined with L. reuteri, which was ablated by the monocarboxylate transporter (MCT) inhibitor 7ACC1 or MCT1 disruption in inguinal white adipose tissues to block propionate transport.

CONCLUSIONS

Our data demonstrate a functional axis among L. reuteri, propionate, and beige fat tissue in the anti-obesity action of CQA through the regulation of thermogenesis. These findings provide mechanistic insights into the therapeutic use of herbal ingredients with poor bioavailability via their interaction with the gut microbiota. Video Abstract.