Oleic acid regulates the circadian rhythm of adipose tissue in obesity.

The effect of oleic acid (OA) on the regulation of the circadian rhythm present in human visceral (VAT) and subcutaneous (SAT) adipose tissue from patients with morbid obesity has not been analyzed yet. VAT and SAT explants from patients with morbid obesity were incubated with OA to analyze the circadian regulation of clock and other genes related to lipid metabolism (SREBP-1c, FAS, LPL and CPT1), and their association with baseline variables and the improvement of these patients after bariatric surgery. There were significant differences in amplitude and acrophase in VAT with respect to SAT. In VAT, body weight negatively correlated with BMAL1 and CRY1 amplitude, and REVERBα acrophase; body mass index (BMI) negatively correlated with REVERBα acrophase; and waist circumference negatively correlated with PER3 acrophase. In SAT, BMI negatively correlated with CLOCK amplitude, and CLOCK, REVERBα and CRY2 MESOR; and waist circumference negatively correlated with PER3 amplitude and acrophase. A greater short-term improvement of body weight, BMI and waist circumference in patients with morbid obesity after bariatric surgery was associated with a lower CRY1 and CRY2 amplitude and an earlier PER1 and PER3 acrophase in SAT. OA produced a more relevant circadian rhythm and increased the amplitude of most clock genes and lipid metabolism-related genes. OA regulated the acrophase of most clock genes in VAT and SAT, placing CLOCK/BMAL1 in antiphase with regard to the other genes. OA increased the circadian rhythmicity, although with slight differences between adipose tissues. These differences could determine its different behavior in obesity.

Protein kinase D1 deletion in adipocytes enhances energy dissipation and protects against adiposity.

Nutrient overload in combination with decreased energy dissipation promotes obesity and diabetes. Obesity results in a hormonal imbalance, which among others activates G protein-coupled receptors utilizing diacylglycerol (DAG) as secondary messenger. Protein kinase D1 (PKD1) is a DAG effector, which integrates multiple nutritional and hormonal inputs, but its physiological role in adipocytes is unknown. Here, we show that PKD1 promotes lipogenesis and suppresses mitochondrial fragmentation, biogenesis, respiration, and energy dissipation in an AMP-activated protein kinase (AMPK)-dependent manner. Moreover, mice lacking PKD1 in adipocytes are resistant to diet-induced obesity due to elevated energy expenditure. Beiging of adipocytes promotes energy expenditure and counteracts obesity. Consistently, deletion of PKD1 promotes expression of the ß3-adrenergic receptor (ADRB3) in a CCAAT/enhancer binding protein (C/EBP)-α- and δ-dependent manner, which leads to the elevated expression of beige markers in adipocytes and subcutaneous adipose tissue. Finally, deletion of PKD1 in adipocytes improves insulin sensitivity and ameliorates liver steatosis. Thus, depletion of PKD1 in adipocytes increases energy dissipation by several complementary mechanisms and might represent an attractive strategy to treat obesity and its related complications.

Taurine supplementation in conjunction with exercise modulated cytokines and improved subcutaneous white adipose tissue plasticity in obese women.

Interventions that can modulate subcutaneous white adipose tissue (scWAT) function, such as exercise training and nutritional components, like taurine, modulate the inflammatory process, therefore, may represent strategies for obesity treatment. We investigated the effects of taurine supplementation in conjunction with exercise on inflammatory and oxidative stress markers in plasma and scWAT of obese women. Sixteen obese women were randomized into two groups: Taurine supplementation group (Tau, n = 8) and Taurine supplementation + exercise group (Tau + Exe, n = 8). The intervention was composed of daily taurine supplementation (3 g) and exercise training for 8 weeks. Anthropometry, body fat composition, and markers of inflammatory and oxidative stress were determined in plasma and scWAT biopsy samples before and after the intervention. We found that, although taurine supplementation increased taurine plasma levels, no changes were observed for the anthropometric characteristics. However, Tau alone decreased interleukin-6 (IL-6), and in conjunction with exercise (Tau + Exe), increased anti-inflammatory interleukins (IL-15 and IL10), followed by reduced IL1ß gene expression in the scWAT of obese women. Tau and Tau + Exe groups presented reduced adipocyte size and increased connective tissue and multilocular droplets. In conclusion, taurine supplementation in conjunction with exercise modulated levels of inflammatory markers in plasma and scWAT, and improved scWAT plasticity in obese women, promoting protection against obesity-induced inflammation. TRN NCT04279600 retrospectively registered on August 18, 2019.

PTIP Deficiency in B Lymphocytes Reduces Subcutaneous Fat Deposition in Mice.

Recent studies have predominantly focused on the role of B cells in metabolic diseases, yet the function of B cells in adipose homeostasis remains unclear. Pax transactivation domain-interacting protein (PTIP), a licensing factor for humoral immunity, is necessary for B cell development and activation. Here, using mice that lack PTIP in B cells (PTIP-/- mice), we explored the role of B cells in adipose homeostasis under physiological conditions. Fat deposition in 8-week-old mice was measured by micro-CT, and PTIP-/- mice presented a marked decrease in the deposition of subcutaneous adipose tissue (SAT). Untargeted lipidomics revealed that the triglyceride composition in SAT was altered in PTIP-/- mice. In addition, there was no difference in the number of adipocyte progenitor cells in the SAT of wild-type (WT) and PTIP-/- mice as measured by flow cytometry. To study the effects of steady-state IgM and IgG antibody levels on fat deposition, PTIP-/- mice were injected intraperitoneally with serum from WT mice once every 3-4 days for 4 weeks. The iSAT mass of the recipient mice showed no significant increase in comparison to the controls after 4 weeks of injections. Our findings reveal that PTIP plays an essential role in regulating subcutaneous adipocyte size, triglyceride composition, and fat deposition under physiological conditions by controlling B cells. The decreased subcutaneous fat deposition in PTIP-/- mice does not appear to be related to the number of adipocyte progenitor cells. The steady-state levels of IgM and IgG antibodies in vivo are not associated with the subcutaneous fat deposition.

Visceral-to-Subcutaneous Fat Ratio Is a Potential Predictor of Postoperative Complications in Colorectal Cancer.

BACKGROUND Colorectal cancer (CRC) is one of the most common malignant tumors. Surgery is the primary treatment for CRC. Recent studies have shown that visceral-to-subcutaneous fat ratio (VSR) may be a potential indicator of risk. The aim of the present study was to determine whether VSR is a suitable predictor of the impact of postoperative complications in CRC. MATERIAL AND METHODS Clinical data from 129 patients were analyzed retrospectively. All patients underwent laparoscopic surgery for CRC. Preoperative imaging was used to quantify VSR. The primary outcome was 30-day postoperative complications. Multivariate logistic regression was used to determine the association between obesity indexes and postoperative complications. RESULTS There were 129 patients who underwent primary resections of colorectal cancer. At 30 days after surgery, postoperative complications had occurred in 33 (25.6%) patients. VSR was significantly associated with postoperative complications in multivariate analysis (P=0.032, OR 6.103, 95% CI 1.173-31.748). In ROC analysis, VSR was a potential predictor of complications (AUC 0.650). A cutoff value of VSR ≥0.707 was associated with 60% sensitivity and 29% specificity for postoperative complications. Patients with VSR ≥0.707 had 41.7% risk of morbidity, whereas those with <0.707 had 16.0% risk (P=0.001). CONCLUSIONS Our study shows that VSR is superior to VFA for prediction of the risk of complications following CRC laparoscopic surgery. We have also identified the optimal cutoff values for the use of VSR for this purpose. Measurement of VSR and identifying patients with increased risk of postoperative complications facilitate making perioperative decisions.

Skeletal muscle size distribution in large-sized male and female athletes.

OBJECTIVE: In healthy adults, it is generally accepted that women have less upper body muscle mass compared to men. However, it is unknown whether there are sex differences in skeletal muscle distribution in highly trained large-sized athletes. Our aim was to compare the skeletal muscle size distribution between large-sized male and female athletes. METHODS: Ten female athletes (>80 kg body mass) and twenty-one male athletes (>100 kg body mass) had muscle thickness (MT) and subcutaneous adipose tissue thickness measured by ultrasound at nine sites on the anterior and posterior aspects of the body. Total muscle mass (SM) was estimated from an ultrasound-derived prediction equation. Body fat percentage and fat-free mass were calculated from ultrasound measured subcutaneous fat thickness. RESULTS: The average SM in female athletes (30.0 kg) was approximately 70% of the mean value of the male athletes (45.3 kg).With respect to MT, the relative values of femaleto male athletes were 68% to 78% in the upper body and 85% to 92% in the lower body. Similar results were observed when analyzing data for male and female athletes (n = 5 each) who were pair matched for height. CONCLUSION: The relative values of MT for female/male athletes were higher in the lower body compared to the upper body. This is similar to that observed in healthy non-athletes indicating that this difference is not due to resistance training. The lower muscle mass in the arms and trunk of females appears to be a true sex difference but the cause of this difference is unknown.

Echo intensity as an indicator of skeletal muscle quality: applications, methodology, and future directions.

PURPOSE: This narrative review provides an overview of the current knowledge of B-mode ultrasound-derived echo intensity (EI) as an indicator of skeletal muscle quality. METHOD: PubMed and Google Scholar were used to search the literature. Advanced search functions were used to find original studies with the terms 'echo intensity' and/or 'muscle quality' in the title and/or abstract. Publications that conceptually described muscle quality but did not include measurement of EI were not a focus of the review. RESULT: Importantly, the foundational premise of EI remains unclear. While it is likely that EI reflects intramuscular adiposity, data suggesting that these measurements are influenced by fibrous tissue is limited to diseased muscle and animal models. EI appears to show particular promise in studying muscular aging. Studies have consistently reported an association between EI and muscle function, though not all chronic interventions have demonstrated improvements. Based on the existing literature, it is unclear if EI can be used as a marker of muscle glycogen following exercise and nutritional interventions, or if EI is influenced by hydration status. Inconsistent methodological approaches used across laboratories have made comparing EI studies challenging. Image depth, rest duration, participant positioning, probe tilt, and the decision to correct for subcutaneous adipose tissue thickness are all critical considerations when interpreting the literature and planning studies. CONCLUSION: While some areas show conflicting evidence, EI shows promise as a novel tool for studying muscle quality. Collaborative efforts focused on methodology are necessary to enhance the consistency and quality of the EI literature.

Impact of skeletal muscle IL-6 on subcutaneous and visceral adipose tissue metabolism immediately after high- and moderate-intensity exercises.

White adipose tissue is a major energy reserve for the body and is essential for providing fatty acids for other tissues when needed. Skeletal muscle interleukin-6 (IL-6) has been shown to be secreted from the working muscle and has been suggested to signal to adipose tissue and enhance lipolysis. The aim of the present study was to investigate the role of skeletal muscle IL-6 in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) lipolysis and glyceroneogenesis with prolonged moderate-intensity exercise and high-intensity exercise in mice. Female inducible muscle-specific IL-6 knockout (IL-6 iMKO) mice and littermate control (Floxed) mice performed a single exercise bout for either 120 min at 16 m/min and 10° slope (moderate intensity) or 30 min at 20 m/min and 10° slope (high intensity), or they remained rested (rest). Visceral and subcutaneous adipose tissues, quadriceps muscles, and blood were quickly obtained. Plasma IL-6 increased in Floxed mice but not in IL-6 iMKO mice with high-intensity exercise. VAT signal transducer and activator of transcription (STAT)3Tyr705 phosphorylation was lower, and VAT hormone-sensitive lipase (HSL)Ser563 phosphorylation was higher in IL-6 iMKO mice than in Floxed mice at rest. Furthermore, HSLSer563 and HSLSer660 phosphorylation increased in VAT and phosphoenolpyruvate carboxykinase protein decreased in SAT with moderate-intensity exercise in both genotypes. On the other hand, both exercise protocols increased pyruvate dehydrogenaseSer232 phosphorylation in VAT only in IL-6 iMKO mice and decreased tumor necrosis factor-α messenger RNA in SAT and VAT only in Floxed mice. In conclusion, the present findings suggest that skeletal muscle IL-6 regulates markers of lipolysis in VAT in the basal state and pyruvate availability for glyceroneogenesis in VAT with exercise. Moreover, skeletal muscle IL-6 may contribute to exercise-induced anti-inflammatory effects in SAT and VAT.

Lymphatic vessels in human adipose tissue.

Despite being considered present in most vascularised tissues, lymphatic vessels have not been properly shown in human adipose tissue (AT). Our goal in this study is to investigate an unanswered question in AT biology, regarding lymphatic network presence in tissue parenchyma. Using human subcutaneous (S-) and visceral (V-) AT samples with whole mount staining for lymphatic specific markers and three-dimensional imaging, we showed lymphatic capillaries and larger lymphatic vessels in the human VAT. Conversely, in the human SAT, microcirculatory lymphatic vascular structures were rarely detected and no initial lymphatics were found.

Aging Changes of the Superficial Fat Compartments of the Midface Over Time: A Magnetic Resonance Imaging Study.

BACKGROUND: Studies involving superficial facial fat compartments are few in number with conflicting results. Most of them involved small study groups and compared measurements between different populations of young and old subjects either on cadavers or living subjects. OBJECTIVE: To clarify volumetric and dimensional changes in midfacial superficial fat compartment retrospectively in patients who underwent a repeat magnetic resonance imaging (MRI) without gross pathology. MATERIALS AND METHODS: A total of 70 patients with a mean age of 60 years (range: 33-82 years) and a median elapsed time of 44.5 months (range: 32-64 months) between 2 MRIs were included. Magnetic resonance imaging scans were analyzed in the axial and sagittal planes to obtain measurements of the medial part of the superficial cheek fat. Superficial cheek fat was divided into 3 compartments. Thickness, width, and height were measured, and volumes were calculated for each compartment on both hemifaces. RESULTS: Volume and thickness were decreased significantly in all compartments (p < .05). The width was decreased in superior and middle compartments, whereas increased in lower compartment indicating dislocation of the fat tissue (p < .05). Height was also significantly increased (p < .05). A subgroup analysis has shown that there was no significant difference between men and women. CONCLUSION: This study clarifies that aging is associated with a significant decrease in superficial midfacial fat tissue volume and thickness both in women and men. The decrease in width in upper and middle compartments, but increase in lower compartment suggests a volume shift within superficial fat tissue.

Compression Garment-induced Leg Changes Increase Hemodynamic Responses in Healthy Individuals.

This study evaluated the morphological changes of the lower limb and associated hemodynamic responses to different lower-body compression pressures (COMPs) in physically active, healthy individuals at rest. Each of the 32 participants underwent three trials with three different degrees of lower-body compression applied: "Low" (2.2±1.4 mmHg), "Medium" (12.9±3.9 mmHg), and "High" (28.8±8.3 mmHg). In each COMP, a cross-sectional area of leg muscles (CSAmuscle), subcutaneous fat (CSAfat), superficial vessels (SupV), deep arteries (DA), and deep veins (DV) at the calf, knee, and thigh levels were measured using magnetic resonance imaging (MRI). Additionally, blood pressure (BP), heart rate (HR), cardiac output (CO), stroke volume (SV), and systemic vascular resistance (SVR) were measured using Doppler ultrasound (USCOM®). With High COMP, calf CSAmuscle and SupV were smaller (p<0.01), whereas DA and DV were larger (p<0.05). Calf CSAfat, however, was similar among all COMPs. There were no major changes in CSAmuscle and CSAfat at knee and thigh levels. CO (3.2±0.9 L/min) and SV (51.9±16.4 mL) were higher (p<0.05) only with High COMP, but other hemodynamic variables showed no significant changes across different COMPs. The High COMP at the lower limb induces leg morphological changes and increases associated hemodynamic responses of physically active healthy individuals at rest.

The metabolic cost of subcutaneous and abdominal rewarming in king penguins after long-term immersion in cold water.

Marine endotherms in the polar regions face a formidable thermal challenge when swimming in cold water. Hence, they use morphological (fat, blubber) adjustment and peripheral vasoconstriction to reduce demands for heat production in water. The animals then regain normothermia when resting ashore. In the king penguin (Aptenodytes patagonicus) metabolic rate is lower in fed than in fasted individuals during subsequent rewarming on land. This has been suggested to be a consequence of diversion of blood flow to the splanchnic region in fed birds, which reduces peripheral temperatures. However, peripheral temperatures during recovery have never been investigated in birds with different nutritional status. The aim of this study was, therefore, to measure subcutaneous and abdominal temperatures during the rewarming phase on land in fasted and fed king penguins, and investigate to which extent any different rewarming were reflected in recovery metabolic rate (MRR) after long term immersion in cold water. We hypothesized that fed individuals would have a slower increase of subcutaneous temperatures compared to fasted penguins, and a correspondingly lower MRR. Subcutaneous tissues reached normothermia after 24.15 (back) and 21.36 min (flank), which was twice as fast as in the abdomen (46.82 min). However, recovery time was not affected by nutritional condition. MRR during global rewarming (4.56 ± 0.42 W kg-1) was twice as high as resting metabolic rate (RMR; 2.16 ± 0.59 W kg-1). However, MRR was not dependent on feeding status and was significantly elevated above RMR only until subcutaneous temperature had recovered. Contrary to our prediction, fed individuals did not reduce the subcutaneous circulation compared to fasted penguins and did not show any changes in MRR during subsequent recovery. It seems likely that lower metabolic rate in fed king penguins on land reported in other studies might not have been caused primarily by increased circulation to the visceral organs.

Subcutaneous Adipose Tissue in Female Volleyball Players: Is It Related with Performance Indices?

The aim of the present study was to examine subcutaneous adipose tissue distribution in female volleyball players with regards to (a) variation by anatomical site, (b) differences among age groups and playing positions, and (c) physiological characteristics associated with performance. Participants were adolescent (n = 89, age 15.6 ± 0.9 years, mean ± standard deviation) and adult female volleyball players (n = 78, 24.8 ± 5.3 years), who performed a series of anthropometric and performance tests including skinfold thickness in 10 sites, Abalakov jump (AJ) and handgrip test (HG). Chin had the smallest thickness, and iliac crest and abdomen the largest. The largest correlations of skinfold thickness were shown with regards to AJ ad HG. Coefficient of variations in skinfold thickness correlated with performance indices with small magnitude. Triceps and chin were the most frequent predictors of performance indices. The anatomical site of skinfold was near the active muscle groups related to performance in HG. In conclusion, performance indices such AJ and HG were related with thickness of specific skinfolds and with the variation of thickness by anatomical site (i.e., the less the variation, the better the performance). Considering the relevance of specific skinfolds (e.g., triceps and chin) for performance, their further use would be recommended for purposes of training monitoring, volleyball players' selection and talent identification.

Relationship of mesenteric panniculitis with visceral and subcutaneous adipose tissue

Background/aim: Mesenteric panniculitis (MP) is an idiopathic benign disease characterized by fat necrosis, chronic inflammation, and fibrosis. The relationship between obesity and chronic low-grade inflammation has been reported. This study investigated the relationship of MP diagnosed using multidetector computed tomography (MDCT) with visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) areas. Materials and methods: We retrospectively enrolled 104 patients with no radiological findings other than MP. Additionally, 76 individuals without any indicative radiological findings were included as controls. VAT and SAT were separately calculated (cm2) using a 3-dimensional workstation. The abdominal circumference was measured (cm). Results: The mean abdominal circumference was 99.9 ± 7.9 cm, SAT was 195.3 ± 89.1 cm2, and VAT was 203.9 ± 72.8 cm2 in the MP group. The abdominal circumference, VAT, and SAT were significantly higher in the MP group than in the control group (P < 0.001). According to the receiver operating characteristic (ROC) analysis, cut-off level VAT and SAT were 167.5 cm2 (sensitivity 71%, specificity 69%) and 117.5 cm2 (sensitivity 78%, specificity 51 %), respectively. Conclusion: Increased VAT and SAT were associated with MP, suggesting their role in the etiology of MP.

Role of OXCT1 in ovine adipose and preadipocyte differentiation.

3-oxoacid CoA-transferase 1 (OXCT1) is a key enzyme in ketone body metabolism that is expressed in adipose and other tissues. The present study addressed the function of OXCT1 in adipose tissue from Tan sheep. The 1563 bp ovine OXCT1 coding sequence was cloned from ovine adipose tissue. The OXCT1 protein sequence was highly homologous to OXCT1 from other species. OXCT1 was highly expressed in kidney and at lower levels in small intestine, lung, spleen, heart, stomach, liver, tail adipose, and cartilage, but not in longissimus muscle. OXCT1 was expressed at higher levels in perirenal and tail adipose tissues than in subcutaneous adipose tissue. OXCT1 expression levels increased during the in vitro differentiation of adipocytes, but decreased dramatically at day 8. OXCT1 knockdown in ovine adipocytes promoted lipid accumulation, whereas overexpression did the converse. This study demonstrates that OXCT1 may play a role in adipogenesis and provides new insight on adipose deposition in sheep.

A low visceral fat proportion, independent of total body fat mass, protects obese adolescent girls against fatty liver and glucose dysregulation: a longitudinal study.

BACKGROUND: The relative proportion of visceral fat (VAT) to subcutaneous fat (SAT) has been described as a major determinant of insulin resistance (IR). Our study sought to evaluate the effect of body fat distribution on glucose metabolism and intrahepatic fat content over time in a multiethnic cohort of obese adolescents. SUBJECTS/METHODS: We examined markers of glucose metabolism by oral glucose tolerance test, and body fat distribution by abdominal MRI at baseline and after 19.2 ± 11.4 months in a cohort of 151 obese adolescents (88 girls, 63 boys; mean age 13.3 ± 3.4 years; mean BMI z-score 2.15 ± 0.70). Hepatic fat content was assessed by fast-gradient MRI in a subset of 93 subjects. We used the median value of VAT/(VAT + SAT) ratio within each gender at baseline to stratify our sample into high and low ratio groups (median value 0.0972 in girls and 0.118 in boys). RESULTS: Female subjects tended to remain in their VAT/(VAT + SAT) category over time (change over follow-up P = 0.14 among girls, and P = 0.04 among boys). Baseline VAT/(VAT + SAT) strongly predicted the hepatic fat content, fasting insulin, 2-h glucose, and whole-body insulin sensitivity index at follow-up among girls, but not in boys. CONCLUSIONS: The VAT/(VAT + SAT) ratio is a major determinant of impaired glucose metabolism and hepatic fat accumulation over time, and its effects are more pronounced in girls than in boys.

Subcutaneous fat mass in infancy and abdominal, pericardial and liver fat assessed by Magnetic Resonance Imaging at the age of 10 years.

BACKGROUND/OBJECTIVES: Fat mass development in infancy contributes to later adiposity, but its relation to ectopic fat depots is unknown. We examined the associations of infant subcutaneous fat with childhood general and organ-specific fat. SUBJECTS/METHODS: Among 593 children from a population-based prospective cohort study, we obtained total subcutaneous fat mass (as sum of biceps, triceps, suprailiacal, and subscapular skinfolds thickness), central-to-total subcutaneous fat ratio (sum of suprailiacal and subscapular skinfold thickness/total subcutaneous fat) at 1.5, 6 and 24 months of age. At 10 years, we assessed BMI, fat mass index (FMI) based on total body fat by dual-energy X-ray absorptiometry, and abdominal subcutaneous, visceral and pericardial fat mass indices, and liver fat fraction by Magnetic Resonance Imaging. RESULTS: A higher central-to-total subcutaneous fat ratio at 1.5 months only and higher total subcutaneous fat at 6 and 24 months were associated with higher BMI, FMI and subcutaneous fat mass index at 10 years. The observed associations were the strongest between total subcutaneous fat at 24 months and these childhood outcomes (difference per 1-SDS increase in total subcutaneous fat: 0.15 SDS (95% Confidence Interval (CI) 0.08, 0.23), 0.17 SDS (95% CI 0.10, 0.24), 0.16 SDS (95% CI 0.08, 0.23) for BMI, FMI and childhood subcutaneous fat mass index, respectively). Infant subcutaneous fat measures at any time point were not associated with visceral and pericardial fat mass indices, and liver fat fraction at 10 years. CONCLUSIONS: Our results suggest that infant subcutaneous fat is associated with later childhood abdominal subcutaneous fat and general adiposity, but not with other organ-specific fat depots.

Subcutaneous adipose tissue distribution and telomere length.

Background Overweight and obese individuals have a reduced life expectancy due to cardiovascular disease (CVD), type 2 diabetes, stroke and cancer. Systemic inflammation and premature telomere shortening have been discussed as potential mechanisms linking these conditions. We investigated the relation of subcutaneous adipose tissue (SAT) distribution to leukocyte relative telomere length (RTL). Methods We measured RTL in 375 participants of the observational STYJOBS/EDECTA cohort (ClinicalTrials.gov Identifier NCT00482924) using a qPCR based method. SAT distribution was determined by lipometry yielding a percent body fat value and SAT thicknesses at 15 standardized locations across the entire body. A correlation analysis between RTL, age, sex, lipometry data and conventional body measures (body mass index [BMI], waist-, hip circumference, waist-to-hip ratio, waist-to-height ratio) was calculated. The strongest determinants of RTL were determined by a stepwise multiple regression analysis. Results RTL was not associated with age or sex. RTL was significantly negatively correlated with BMI, percent body fat, waist-, hip circumference and waist-to-height ratio. Furthermore, RTL correlated with SAT at the following locations: neck, triceps, biceps, upper back, front chest, lateral chest, upper abdomen, lower abdomen, lower back, hip, front thigh, lateral thigh, rear thigh and calf. Stepwise regression analysis revealed nuchal and hip SAT as the strongest predictors of RTL. No significant association was seen between RTL and waist-to-hip ratio. Conclusions RTL is negatively associated with parameters describing body fat composure. Nuchal and hip SAT thicknesses are the strongest predictors of RTL. Central obesity appears to correlate with premature genomic aging.

Non-Surgical Fat Reduction and Topical Modulation of Adipose Tissue Physiology

Non-surgical fat reduction procedures have gained in popularity over the past few years and remain in great demand. The process results in accumulation of breakdown products, lipid droplets, that are slowly absorbed over a period of months. This paper outlines the physiological process whereby lipid droplets are absorbed through a process of autophagy (lipophagy) involving a repackaging of these droplets to smaller sizes so that macrophages can then cope with digestion of these very large particles. Furthermore, a fat compartment is described within the dermis surrounding the tail of the hair follicle, which is attracting much attention due to its unique phenotype, function, and connection to the deeper subcutaneous fat compartment. This provides an entry route for direct signaling to the subcutaneous fat. Related to these novel concepts, peptides can be designed in liposomal delivery systems to target lipid droplet breakdown via the hair follicle entry route. This concept is elucidated in this paper. J Drugs Dermatol. 2019;18(4):375-380.