Abdominal Subcutaneous Fat Tissue Research Articles

99mTc]Tc-hydroxydiphosphonate uptake in soft tissue is associated with amyloid load in subcutaneous abdominal fat tissue and mortality in wild-type transthyretin amyloidosis patients.

Bone scintigraphy is key to non-invasively diagnosing wild-type transthyretin (ATTRwt) amyloidosis, and is mainly used to assess cardiac radiotracer uptake. However, extracardiac radiotracer uptake is also observed. We investigated whether intensity of soft tissue radiotracer uptake is associated with amyloid load in subcutaneous abdominal fat tissue and with mortality. This prospective cohort study included 94 ATTRwt amyloidosis patients and 26 amyloid-negative heart failure controls who underwent whole-body [99mTc]Tc-hydroxydiphosphonate scintigraphy. Site-to-background ratios were calculated for heart, elbows, subcutaneous tissue, shoulders and wrists on anterior planar bone scintigraphy images using rib and whole-body radiotracer uptake as background. Fat tissue aspirates were stained with Congo red to grade amyloid load. Site-to-rib ratios were compared between ATTRwt amyloidosis patients and controls, and associations of site-to-background ratio with Congo red score and all-cause mortality were studied. ATTRwt amyloidosis patients had higher soft tissue-to-rib, heart-to-rib and heart-to-whole body ratios compared with controls. The intensity of soft tissue uptake was positively associated with amyloid load in fat tissue in ATTRwt amyloidosis patients. Estimated glomerular filtration rate, N-terminal brain natriuretic propeptide, high-sensitivity cardiac troponin T (hs-cTnT), and the prognostic Mayo and NAC staging system were associated with all-cause mortality in univariable models. Soft tissue/rib ratio, hs-cTnT and the prognostic staging systems were the only two variables that were independently associated withall-cause mortality. Soft tissue radiotracer uptake on bone scintigraphy in ATTRwt amyloidosis patients is positively associated with amyloid load in abdominal fat tissue and is independently associated with mortality.

ELISA-4-amyloid: diagnostic accuracy of an ELISA panel for typing the four main types of systemic amyloidosis in subcutaneous abdominal fat tissue samples

Background Reliable typing of amyloid is essential. Amyloid extraction from tissue enables immunochemical typing of the precursor protein using an enzyme-linked immunosorbent assay (ELISA). Objective To assess the diagnostic accuracy of a panel of ELISAs for typing the four main types (AA, ATTR, AL-kappa and AL-lambda amyloid). Methods From 1996 to 2023 subcutaneous abdominal fat tissue aspirates were obtained from 1339 amyloidosis patients and 868 controls. Amyloid was visually graded 0–4+ in Congo red-stained smears. Amyloid extracted from tissue by Guanidine was typed using a panel comprising four ELISAs. Results All amyloid protein concentrations in extracts correlated with amyloid grade in smears. Typing sensitivity was low (23.3%) in samples with grade 1+/2+ amyloid. Overall typing sensitivity of the panel was 81.6% for all easily visible amyloid (grade 3+/4+): high for AA (98.8%) and ATTR (96.8%) and fair for AL-kappa (66.7%) and AL-lambda (75.9). Overall typing specificity was 98.0% and the overall positive predictive value was 98.0%. Conclusions We describe a highly specific ELISA panel for routine typing of the main amyloid types in fat tissue. Until more sensitive typing techniques will become generally available, typing easily visible amyloid in fat tissue using this ELISA panel is reliable, affordable and straightforward.

Bioelectrical Impedance Analysis Detects Body Fat Changes After Surgical Subcutaneous Fat Removal.

Background: The risk and metabolic effects of obesity are determined by the distribution of fat throughout the body. It has been proposed that the distribution of abdominal fat is more closely related to the metabolic risks of obesity. High prevalence of overweight and obesity has thereby contributed to an increased uptake of surgical subcutaneous fat removal (SSFR) procedures. The goal of this study was to determine whether bioelectrical impedance analysis (Tanita system) can be used to detect the removal of excess abdominal subcutaneous fat tissue during SSFR when studying the metabolic effects of such procedures. Methods: Study population comprised patients who received body contouring procedures at the Hamad General Hospital's plastic surgery department between November 2020 and December 2022. To evaluate the factors of interest, subjects were prospectively followed up at two time points: within 1 week before the surgery and within 1-2 weeks thereafter. The following factors were measured: body weight, body fat percentage, body fat mass, body mass index (BMI), fat-free mass, estimated muscle mass, total body water, visceral fat score, and basal metabolic rate. Results: In total, 22 patients were included in the study. The two visits' medians for height, weight, BMI, fat percent (fat%), fat mass, visceral fat rating, and Doi's weighted average glucose (dwAG) were compared. Only in the case of Tanita fat% and fat mass, were the preoperative and postoperative medians significantly different. Furthermore, there was no association between these Tanita measures and dwAG or homeostatic model assessment (HOMA; insulin resistance [IR]) changes (before and after surgery). Tanita measures overestimated fat loss, as seen by the mountain plot and Bland-Altman plot agreement methods. Conclusions: Our findings indicated that the only two Tanita measures exhibited meaningful early associations with the amount of tissue excised which were fat mass and fat% differences. Although dwAG and HOMA-IR are not impacted immediately postsurgery, a trend was seen that suggested improvements in those parameters, even though the changes are not clinically significant.

Longitudinal analysis of serum neurofilament light chain levels as marker for neuronal damage in hereditary transthyretin amyloidosis

Objective To evaluate serum neurofilament light chain (sNfL) as biomarker of disease onset, progression and treatment effect in hereditary transthyretin (ATTRv) amyloidosis patients and TTR variant (TTRv) carriers. Methods sNfL levels were assessed longitudinally in persistently asymptomatic TTRv carriers (N = 12), persistently asymptomatic ATTRv amyloidosis patients (defined as asymptomatic patients but with amyloid detectable in subcutaneous abdominal fat tissue) (N = 8), in TTRv carriers who developed polyneuropathy (N = 7) and in ATTRv amyloidosis patients with polyneuropathy on treatment (TTR-stabiliser (N = 20) or TTR-silencer (N = 18)). Polyneuropathy was confirmed by nerve conduction studies or quantitative sensory testing. sNfL was analysed using a single-molecule array assay. Results sNfL increased over 2 years in persistently asymptomatic ATTRv amyloidosis patients, but did not change in persistently asymptomatic TTRv carriers. In all TTRv carriers who developed polyneuropathy, sNfL increased from 8.4 to 49.8 pg/mL before the onset of symptoms and before polyneuropathy could be confirmed neurophysiologically. In symptomatic ATTRv amyloidosis patients on a TTR-stabiliser, sNfL remained stable over 2 years. In patients on a TTR-silencer, sNfL decreased after 1 year of treatment. Conclusion sNfL is a biomarker of early neuronal damage in ATTRv amyloidosis already before the onset of polyneuropathy. Current data support the use of sNfL in screening asymptomatic TTRv carriers and in monitoring of disease progression and treatment effect.

Adiposity, fat depots and the prediction of stroke.

Despite the progress in research, the utility of clinical assessment for the prediction of stroke is limited. The aim herein, was to evaluate the predictive values of major ultrasound indexes of carotid artery and fat depots for stroke in patients with high and very high cardiovascular (CV) risk. The study group included 364 patients (age: 61.3 ± 7.2 years old) with typical CV risk factors scheduled for elective coronary angiography (2012-2013). A comprehensive baseline assessment included the following ultrasound indexes: carotid artery intima-media thickness (IMT), extra-media thickness (EMT), epicardial (EFT) and pericardial fat thickness (PFT), abdominal subcutaneous (ASF) and visceral fat (AVF) and combined periarterial adipose tissue intima-media adventitia (PATIMA) index. Afterwards, all patients were followed for 80.9 ± 7.1 months. There were 23 strokes and 25 cases with new-onset atrial fibrillation during follow-up. Receiver operating characteristics (ROC) analysis showed, that selected clinical parameters (age, waist circumference [WC], waist-hip ratio [WHR]) and ultrasound indexes (EFT: area under curve [AUC] 0.672, p < 0.01 and PATIMA index: AUC 0.658, p < 0.01) were predictive for stroke. However, their predictive values showed no significant differences (p = NS). The baseline body mass index (BMI) was the only parameter, which showed a prediction for new-onset atrial fibrillation (BMI > 33 kg/m2: sensitivity 65%, specificity 76%). It was found that age, WC and echocardiographic EFT revealed significant predictive values for stroke. Both WC and EFT showed a very high NPV suggesting that they should be implemented into the clinical practice as a tool affirming a very low risk of stroke.

#4067 HYPOXIC PRECONDITIONING FOR THE IMPROVEMENT OF THE REGENERATIVE CAPACITY OF MESENCHYMAL STEM CELLS AND ITS APPLICATION IN HYPERTENSIVE KIDNEY DISEASE

Abstract Background and Aims Autologous mesenchymal stem/stromal cells (MSCs) have emerged as a therapeutic option for many chronic diseases. Hypertensive kidney disease (HKD) might impair MSCs’ reparative ability by altering important biomolecular properties of the cell, but the characteristics of this impairment are unclear. In our previous pre-clinical studies, hypoxic preconditioning (HPC) enhanced MSC angiogenesis and reduced senescence through global gene and protein expression. Thus, we hypothesize that HPC would improve human MSCs by enhancing their functionality and angiogenesis, creating an anti-inflammatory and anti-senescence environment in MSCs from healthy control (HC), hypertensive patients (HTN), and hypertensive kidney disease patients (HKD). Method Human MSCs were collected from abdominal subcutaneous fat tissue biopsy of HC, HTN, and HKD patients (n=12 each). Samples were collected from healthy volunteers with no history of hypertension or kidney disease (HC), patients diagnosed with hypertension controlled with antihypertensive drugs (HTN), and hypertensive patients with eGFR&amp;lt;60 mL/min/1.73 m2 (HKD). MSCs were harvested and cultured in Normoxic (20% O2) or Hypoxic (1% O2) conditions for 24-48 hours. MSC functionality was measured by migration and proliferation. Angiogenic and inflammatory secretome in conditioned media was assessed along with MSC senescence by senescence-associated beta-galactosidase (SA-beta-gal) activity. In addition, transcriptome analysis using RNA-sequencing (n=3/group) and quantitative PCR (qPCR) were performed to evaluate gene expression. Results At baseline, Normoxic HTN-MSCs interestingly had higher proliferation compared to HC. HC-MSC subjected to HPC showed increased proliferation (Figure 1A). SA-β-gal activity tended to decrease after HPC, particularly in the HC group (P = .06). HPC did not affect the release of the pro-angiogenic protein VEGF from MSCs, but increased EGF in HC-MSC, and decreased HGF in HC and HKD MSCs. HPC upregulated the pro-angiogenetic genes, inflammatory gene, and a few senescence genes (Figure 1F). Conclusion HPC has a more favorable functional effect on HC- than on HKD-MSC, reflected in increased proliferation and EGF release, and tends to decrease senescence, whereas it has little effect on HTN or HKD MSCs. These observations may assist in developing novel therapeutic strategies to improve the regenerative capacity of MSCs in patients with hypertensive kidney disease.

Tissue-based diagnosis of systemic amyloidosis: Experience of the informal diagnostic center at Uppsala University Hospital.

Diagnosis of systemic amyloidosis is a clinical challenge and usually relies on a tissue biopsy. We have developed diagnostic methods based on the presence of amyloid deposits in abdominal subcutaneous fat tissue. This tissue is also used to determine the biochemical type of amyloidosis, performed by western blot and immunohistochemical analyses with the aid of in-house developed rabbit antisera and mouse monoclonal antibodies. Mass spectrometric methods are under development for selected cases. The diagnostic outcome for 2018-2020 was studied. During this period, we obtained 1,562 biopsies, of which 1,397 were unfixed subcutaneous fat tissue with varying degrees of suspicion of systemic amyloidosis. Of these, 440 contained amyloid deposits. The biochemical nature of the amyloid was determined by western blot analysis in 319 specimens and by immunohistochemistry in further 51 cases.

Bioimpedance analysis combined with sagittal abdominal diameter for abdominal subcutaneous fat measurement.

Abdominal subcutaneous fat tissue (ASFT) is an independent predictor of mortality. This prospective observational study aimed to establish a rapid, safe, and convenient estimation equation for abdominal subcutaneous fat area (SFA) using bioimpedance analysis (BIA) combined with sagittal abdominal diameter (SAD). A total of 520 adult subjects were recruited and were randomly divided into 2/3 (n = 346) and 1/3 (n = 174) to form a modeling group (MG) and a validation group (VG), respectively. Each subject's abdomen was scanned using computed tomography to obtain target variables (SFACT). Predictor variables for all subjects included bioimpedance index (h2/Z), anthropometric parameters height (h), weight (W), waist circumference (WC), hip circumference (HC), and SAD, along with age and sex (male =1, female = 0). SFA estimation equation SFABIA+SAD was established for the MG using stepwise multiple regression analysis. Cross-validation was performed using VG to evaluate the performance of the SFABIA+SAD estimation equation. Stepwise multiple regression analysis was applied from the MG, including SFABIA+SAD = 49.89 + 1.09 SAD−29.90 Sex + 4.71 W−3.63 h2/Z−1.50 h (r = 0.92, SEE = 28.10 cm2, n = 346, p < 0.001). Mean differences in SFABIA+SAD relative to SFACT were −1.21 ± 21.53, 2.85 ± 27.16, and −0.98 ± 36.6 cm2 at different levels of obesity (eutrophic, overweight, obese), respectively. This study did not have a large number of samples in different fields, so it did not have completely external validity. Application of BIA combined with SAD in anthropometric parameters achieves fast, accurate and convenient SAF measurement. Results of this study provide a simple, reliable, and practical measurement that can be widely used in epidemiological studies and in measuring individual SFA.

The oxytocin signalling gene pathway contributes to the association between loneliness and cardiometabolic health

Increasing evidence has shown adverse effects of loneliness on cardiometabolic health. The neuromodulator and hormone oxytocin has traditionally been linked with social cognition and behaviour. However, recent implications of the oxytocin system in energy metabolism and the overrepresentation of metabolic issues in psychiatric illness suggests that oxytocin may represent a mechanism bridging mental and somatic traits. To clarify the role of the oxytocin signalling system in the link between cardiometabolic risk factors and loneliness, we calculated the contribution of single nucleotide polymorphisms (SNPs) in the oxytocin signalling pathway gene-set (154 genes) to the polygenic architecture of loneliness and body mass index (BMI). We investigated the associations of these oxytocin signalling pathway polygenic scores with body composition measured using body magnetic resonance imaging (MRI), bone mineral density (BMD), haematological markers, and blood pressure in a sample of just under half a million adults from the UK Biobank (BMD subsample n = 274,457; body MRI subsample n = 9796). Our analysis revealed significant associations of the oxytocin signalling pathway polygenic score for BMI with abdominal subcutaneous fat tissue, HDL cholesterol, lipoprotein(a), triglycerides, and BMD. We also found an association between the oxytocin signalling pathway polygenic score for loneliness and apolipoprotein A1, the major protein component of HDL. Altogether, these results provide additional evidence for the oxytocin signalling pathway’s role in energy metabolism, lipid homoeostasis, and bone density, and support oxytocin’s complex pleiotropic effects.

Cryolipolysis for abdominal subcutaneous fat reduction: A prospective, multicenter, single arm, clinical study.

Various treatment methods are used for noninvasive body contouring. To evaluate the efficacy and safety of a newly designed cryolipolysis device using a three-dimensional cooling method for abdominal fat reduction. Twenty-five participants with clinically apparent abdominal fat tissue participated in the study. The thickness of fat tissue below the umbilicus level was measured using a caliper at baseline and 12 weeks after the first treatment. The height of abdominal subcutaneous fat tissue on ultrasonography and participant satisfaction were assessed at every visit for 16 weeks. All adverse events (AEs) during the study period were recorded. p values <0.05 were considered statistically significant. Twenty-four participants completed this study; the mean BMI of participants was 29.34 ± 2.36 kg/m2 . The mean thickness of abdominal subcutaneous fat was significantly lower at 12 weeks (40.4 ± 6.8 mm, p < 0.001) than at baseline (49.3 ± 8.5 mm). Differences in the height of abdominal subcutaneous fat compared to that at baseline were 1.02 ± 0.41 cm (12 weeks, p < 0.001) and 1.13 ± 0.44 cm (16 weeks, p < 0.001). Rates of abdominal subcutaneous fat reduction at 12 and 16 weeks compared to that at baseline were 28.45% and 31.13%, respectively. The ratio of abdominal circumference to hip circumference at 12 and 16 weeks was significantly decreased compared to that at baseline. Most participants (95.8%) reported improvement in satisfaction scores at 16 weeks. There were no serious AEs during the entire study period. The study demonstrated the efficacy of a noninvasive cryolipolysis device using a three-dimensional cooling method for reducing abdominal subcutaneous fat.

FETAL ABDOMINAL SUBCUTANEOUS TISSUE THICKNESS FOR ESTIMATING FETAL BIRTH WEIGHT MEASURED BY ULTRASOUND – ITS RELIABILITY AND ACCURACY IN INDIAN POPULATION

Context: Estimated Fetal weight (EFW) inuences the management and outcome of pregnancy. Commonly used ultrasound fetal weight estimation like Hadlock four parameter method(Hadlock-4) based on fetal biometry is widely used. These formulas show variable degrees of error which is more evident in fetuses with nutritional and metabolic issues; better accuracy of fetal weight estimation can be obtained by incorporation of fetal soft tissue parameters like the fetal subcutaneous tissue in the weight estimation process. To determine if measurement of fetalAims: abdominal subcutaneous tissue thickness (FASTT) for Estimating Fetal birth weight by ultrasound in Indian population. Settings and Design: Method and Materials:Prospective observational study, A study was done in Department of Radio- diagnosis facility of K.V.G. Medical College and Hospital, Sullia, enrolling 100 women of third trimeter pregnancy who underwent ultrasonography and delivered within one week of scan. Abdominal subcutaneous fat tissue thickness of the fetuses was measured, from the inner to the outer aspect of the echogenic subcutaneous fat at the level of the abdominal circumference (AC). Pearson coefcient. Mean age of 100 ladies enrolled was 26 years and 4 months.Statistical analysis used: Results: FASTT was positively correlated with actual birth weight (Pearson's, r = 0.69, p &lt; 0.001). FASTT of &gt; 8.9 mm was sensitive to predict large for gestational age (LGA) babies. FASTT can be used as an additional indicator to predict large forConclusion: gestational age babies along with other known birth weight indicators to make it more reliable in Indian context.

Diagnosis of Senile Amyloidosis by Fine Needle Aspiration Biopsy and Cell Block from Abdominal Fat Pad

Background: Amyloidosis is menacingly increasing medical problem in aging population across globe. Its clinical presentation is varied. Its laboratory diagnosis often requires biopsy material. The fine needle aspiration cytology (FNAC, FNAB) offers dependable diagnostic alternative to cumbersome biopsy. Present protocol describes the FNAC of abdominal pad of fat as surrogate site for diagnosis of senile systemic amyloidosis avoiding biopsy other known sites. &#x0D; Aim: To study diagnostic accuracy of subcutaneous abdominal fat tissue fine needle aspiration cytology/biopsy for detecting systemic (senile) amyloidosis and its utility in clinical practice.&#x0D; Objectives:&#x0D; &#x0D; To diagnose systemic amyloidosis (senile) by fine needle aspiration cytology/biopsy of abdominal fat pad on crush smears of aspirates and cell blocks.&#x0D; To correlate the diagnosis of deposits of amyloid with the clinical manifestations in specific and non specific clinical manifestations of amyloidosis.&#x0D; &#x0D; &#x0D; To know the sensitivity and specificity of the diagnosis of amyloid deposition on fine needle aspiration cytology/biopsy of abdominal fat pad in comparison to the results of cell block preparations.&#x0D; &#x0D; Methodology: A prospective study carried out to compare results of FNAC of abdominal pad of fat with paraffin embedded cell block in diagnosis of amyloidosis in suspected cases of cases of senile systemic amyloidosis. Technical adopted methods to be used are regular tissue stains, congo red stain and polarized microscopy. &#x0D; Expected Results: It is expected that results of study will establish FNAC of abdominal pad of fat as dependable office diagnostic procedure that would avoid complicated biopsy procedures of gastrointestinal tissue, skin, bone marrow and others for senile systemic amyloidosis.

Effect of an Endurance and Strength Mixed Circuit Training on Regional Fat Thickness: The Quest for the "Spot Reduction".

Accumulation of adipose tissue in specific body areas is related to many physiological and hormonal variables. Spot reduction (SR) is a training protocol aimed to stimulate lipolysis locally, even though this training protocol has not been extensively studied in recent years. Thus, the present study sought to investigate the effect of a circuit-training SR on subcutaneous adipose tissue in healthy adults. Methods: Fourteen volunteers were randomly assigned to spot reduction (SR) or to a traditional resistance training (RT) protocol. Body composition via bioimpedance analysis (BIA) and subcutaneous adipose tissue via skinfold and ultrasound were measured before and after eight weeks of training. Results: SR significantly reduced body mass (p < 0.05) and subcutaneous abdominal adipose tissue (p < 0.05). Conclusions: circuit-training SR may be an efficient strategy to reduce in a localized manner abdominal subcutaneous fat tissue depot.

Abstract PS2-23: Prospective study of circulating cancer-associated macrophage-like cells (CAMLs) in obese patients with advanced breast cancer

Abstract Background Cancer-associated macrophage-like cells (CAMLs) are rare circulating gigantic atypical cells exclusively found in the peripheral blood of patients with solid cancers. CAMLs potentially originate from tumor-associated macrophages in the tumor microenvironment and may have a prognostic role in breast cancer. Obesity-induced local hypoxia attracts macrophages to the tumor microenvironment and activates macrophages to induce chronic inflammation, which can lead to breast cancer progression. However, little is known about the relationship between CAMLs, obesity, and body fat distribution. Also, the role of the CAMLs on breast cancer development needs to be investigated. We hypothesized that the number and size of CAMLs are correlated with body mass index (BMI), and we investigated the relationship between CAMLs and body composition. Materials and methods We prospectively collected 10 ml of peripheral blood from 30 patients initially diagnosed with advanced breast cancer who underwent computed tomography. Blood samples were drawn in CellSave tubes to preserve peripheral blood mononuclear cells. We used the CellSieve microfiltering system to isolate and identify CAMLs. After enumerating cells, we analyzed immunofluorescent staining for DAPI, CD14, CD45, CXCR4, and cytokeratin. CAMLs were identified by cell surface markers (CD14+, CD45+, and cytokeratin+) and morphology (multinuclear and giant cells &amp;gt;30 µm). BMI was measured at the time of diagnosis. The in-house 3D imaging analysis software Medical Executable for the Efficient and Robust Quantification of Adipose Tissue was used to calculate the total amount of abdominal visceral fat tissue (VAT) and subcutaneous fat tissue (SAT) between the upper diaphragm and pelvic end using multi-detector computed tomography data. The VAT:SAT ratio was also calculated. We quantified the expression of C-X-C chemokine receptor type 4 (CXCR4) in CAMLs to investigate the metastatic potential of the cells. Finally, we determined the relationship between the characteristics of CAMLs and BMI, body composition parameters, and CXCR4 using the Pearson correlation test. Results Of 30 collected samples, two had an inadequate amount of blood for evaluation. Among the remaining 28, we detected CAMLs in 24. The median BMI was 30.4 kg/m2, and half of the patients were categorized as obese by the World Health Organization BMI classification. BMI was correlated with the number (r=0.39, p=0.043), average size (r=0.42, p=0.039), and maximum size (r=0.50, p=0.013) of CAMLs. In body composition analysis, the maximum size of CAMLs was correlated with the total amount of VAT (r=0.51, p=0.012) and SAT (r=0.44, p=0.037) but not the VAT:SAT ratio. The number of CAMLs was correlated with maximum CXCR4 expression in CAMLs (r=0.58, p=0.004). CAMLs size and CXCR4 expression were inversely correlated. Conclusion The number and size of CAMLs are correlated with BMI, but CAMLs characteristics are not related to body composition. The number of CAMLs was associated with CXCR4, which indicated its metastatic potential. Further studies are needed to elucidate the biological role of CAMLs, especially whether the increased number and size of CAMLs in obesity reflect the tumor microenvironment. Citation Format: Toshiaki Iwase, Aaroh Parikh, Onur Sahin, Akshara S Raghavendra, Maryanne E Sapon, Anjali James, Tushaar V Shrimanker, Sudpreeda Chainitikun, Kumiko Kida, Daniel L Adams, Cha-Mei Tang, Andrea YD Medrano, Ann H Klopp, Naoto T Ueno. Prospective study of circulating cancer-associated macrophage-like cells (CAMLs) in obese patients with advanced breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS2-23.

1866-P: Adipocyte Hypertrophy Is Associated with Increased Dietary Fatty Acid Storage in Adipose Tissue and Reduced Postprandial Hepatic Fatty Acid Uptake and Esterification in Humans

Introduction: Excessive exposure of lean tissues to nonesterified fatty acids (NEFA) leads to insulin resistance (IR). Adipocyte hypertrophy is associated with IR and increase in adipose tissue intracellular triglyceride lipolysis and in NEFA levels, that may contribute to hepatic steatosis and IR. The effect of adipocyte hypertrophy on postprandial hepatic NEFA flux and metabolism and dietary fatty acids (DFA) storage in adipose tissues has not been studied, however. Methods: In 28 healthy adult subjects, fat cell size (FCS) was determined via histomorphologic analysis of abdominal subcutaneous fat tissue. Adipose tissue DFA storage was measured using oral administration of 18FTHA with positron emission tomography (PET). Postprandial hepatic NEFA uptake, oxidation, and esterification were determined using intravenous 11C-palmitate with dynamic PET acquisition. Results: As expected, FCS was correlated positively with fasting glycemia (ρ=0.44, P-value=0.029), homeostasis model assessment-estimated insulin resistance (HOMA-IR) (ρ=0.43, P-value=0.049), and hepatic fat content from CT radiodensity (ρ=0.32, P-value=0.10). FCS was correlated positively with DFA storage in intra-abdominal adipose tissues (ρ=0.48, P-value=0.022) and negatively with postprandial hepatic NEFA uptake (ρ=-0.42, P-value=0.027) and esterification (ρ=-0.58, P-value=0.0080). Conclusion: Adipocyte hypertrophy is associated with increased DFA storage in intra-abdominal adipose tissues and reduced postprandial hepatic NEFA uptake and esterification, despite being associated with greater hepatic fat content, fasting glycemia and HOMA-IR. Adipocyte hypertrophy is thus associated with adipose tissue metabolic adaptation that limits the exposure of the liver to fatty acids in the postprandial period. Disclosure R. Ye: None. S. Phoenix: None. C. Noll: None. E. Montastier: None. F. Frisch: None. L. Bouffard: None. M. Amrani: None. E.E. Turcotte: None. A.C. Carpentier: Advisory Panel; Self; HLS Therapeutics, Inc. Funding Canadian Institutes of Health Research (MOP53094); Centre de recherche du CHUS; Centre d’imagerie moléculaire de Sherbrooke; Faculté de médecine et des sciences de la santé de l’Université de Sherbrooke

Ultrasonography of Quadriceps Femoris Muscle and Subcutaneous Fat Tissue and Body Composition by BIVA in Chronic Dialysis Patients.

Protein Energy Wasting (PEW) in hemodialysis (HD) patients is a multifactorial condition due to specific pathology-related pathogenetic mechanisms, leading to loss of skeletal muscle mass in HD patients. Computed Tomography and Magnetic Resonance Imaging still represent the gold standard techniques for body composition assessment. However, their widespread application in clinical practice is difficult and body composition evaluation in HD patients is mainly based on conventional anthropometric nutritional indexes and bioelectrical impedance vector analysis (BIVA). Little data is currently available on ultrasound (US)-based measurements of muscle mass and fat tissue in this clinical setting. The purpose of our study is to ascertain: (1) if there are differences between quadriceps rectus femoris muscle (QRFM) thickness and abdominal/thigh subcutaneous fat tissue (SFT) measured by US between HD patients and healthy subjects; (2) if there is any correlation between QRFM and abdominal/thigh SFT thickness by US, and BIVA/conventional nutritional indexes in HD patients. We enrolled 65 consecutive HD patients and 33 healthy subjects. Demographic and laboratory were collected. The malnutrition inflammation score (MIS) was calculated. Using B-mode US system, the QRFM and SFT thicknesses were measured at the level of three landmarks in both thighs (superior anterior iliac spine, upper pole of the patella, the midpoint of the tract included between the previous points). SFT was also measured at the level of the periumbilical point. The mono frequency (50 KHz) BIVA was conducted using bioelectrical measurements (Rz, resistance; Xc, reactance; adjusted for height, Rz/H and Xc/H; PA, phase angle). 58.5% were men and the mean age was 69 (SD 13.7) years. QRFM and thigh SFT thicknesses were reduced in HD patients as compared to healthy subjects (p < 0.01). Similarly, also BIVA parameters, expression of lean body mass, were lower (p < 0.001), except for Rz and Rz/H in HD patients. The average QRFM thickness of both thighs at top, mid, lower landmarks were positively correlated with PA and body cell mass (BCM) by BIVA, while negatively correlated with Rz/H (p < 0.05). Abdominal SFT was positively correlated with PA, BCM and basal metabolic rate (BMR) (p < 0.05). Our study shows that ultrasound QRFM and thigh SFT thicknesses were reduced in HD patients and that muscle ultrasound measurements were significantly correlated with BIVA parameters.

The Impact of Lidocaine on Adipose-Derived Stem Cells in Human Adipose Tissue Harvested by Liposuction and Used for Lipotransfer.

The local anesthetic lidocaine, which has been used extensively during liposuction, has been reported to have cytotoxic effects and therefore would be unsuitable for use in autologous lipotransfer. We evaluated the effect of lidocaine on the distribution, number, and viability of adipose-derived stem cells (ASCs), preadipocytes, mature adipocytes, and leukocytes in the fatty and fluid portion of the lipoaspirate using antibody staining and flow cytometry analyses. Adipose tissue was harvested from 11 female patients who underwent liposuction. Abdominal subcutaneous fat tissue was infiltrated with tumescent local anesthesia, containing lidocaine on the left and lacking lidocaine on the right side of the abdomen, and harvested subsequently. Lidocaine had no influence on the relative distribution, cell number, or viability of ASCs, preadipocytes, mature adipocytes, or leukocytes in the stromal-vascular fraction. Assessing the fatty and fluid portions of the lipoaspirate, the fatty portions contained significantly more ASCs (p < 0.05), stem cells expressing the preadipocyte marker Pref-1 (p < 0.01 w/lidocaine, p < 0.05 w/o lidocaine), and mature adipocytes (p < 0.05 w/lidocaine, p < 0.01 w/o lidocaine) than the fluid portions. Only the fatty portion should be used for transplantation. This study found no evidence that would contraindicate the use of lidocaine in lipotransfer. Limitations of the study include the small sample size and the inclusion of only female patients.

The Relationship Between Abdominal Subcutan Fat Tissue Thickness and HbA1c in Pregnant Women

Objective: Obesity is a very common and important health problem and it has become widespread all over the world. Fat tissue is one of the major endocrine organs. Subcutaneous adipose tissue is associated with many diseases such as coronary artery disease, metabolic syndrome, diabetes, impaired lipid profile. Pregnancy is a special condition with metabolic changes involving all systems. We aimed to investigate the relationship and correlation between abdominal fat and HbA1c because of the specific metabolic conditions in pregnancy.Study Design: This is a retrospective study. Ninety-nine (n=99) pregnant women between the ages of 20 and 40 were included in the present study. They have not any other chronic diseases. Ultrasonography was performed between 16.-28. weeks. Abdominal subcutaneous fat tissue was measured during 16-28 weeks of pregnancy. Routine biochemical parameters and HbA1c were evaluated.Results: Subcutaneous fat tissue had a positive correlation with metabolic parameters such as weight and BMI, and a negative correlation with vitamin D level. There is a positive strong correlation with HbA1c level. There was not any correlation between HbA1c and metabolic parameters like triglyceride, LDL, HDL, and cholesterol.Conclusion: There was a strong positive correlation between abdominal subcutaneous fat tissue thickness and HbA1c. However, we didn’t find any correlation between infant weight and metabolic parameters.

Risk factors and complications after body-contouring surgery and the amount of stromal vascular fraction cells found in subcutaneous tissue.

Body contouring surgery following massive weight loss is often prone to complications. Subcutaneous adipose tissue is a rich source of stromal vascular fraction (SVF) cells, and moreover it plays an important role in the pathophysiology of obesity, metabolic syndrome, and wound healing. In this retrospective, single-centred appraisal, complications are examined and correlated with individual SVF numbers in abdominal subcutaneous fat tissue. We analysed whether the weight loss method affected complications. Eighty seven massive weight loss patients undergoing body contouring surgery between 2010 and 2017 were included in the study. In total, 57 cases with at least one complication were recorded (65.5%). Maximum lifetime weight was 109.6 kg (range 48-184 kg). Half of the complications (50.8%) were minor complications without the need for surgical revision. The mean number of SVF found in the resected tissue was 714 997.63 cells/g fat tissue. We found no statistical difference in complication rates dependent on cell numbers. Smoking (P = .049) and a high BMI at the time point of surgery (P = .031) led to significantly more complications. Also, a high resection weight (P = .057) showed a tendency for impaired wound healing. However, there was no difference in complication rates following body contouring procedures attributable to the method of weight loss in this study.

Polyglycolic acid sutures embedded in abdominal acupoints for treatment of simple obesity in adults: a randomized control trial

BackgroundAcupoint catgut embedding therapy characterized by acupoint, needle and catgut are superior to traditional acupuncture, due to exerting more comprehensive therapeutic efficacy. However, it is still deficient in clinical evidence for polyglycolic acid sutures, a novel biodegradable material instead of catgut, embedded for the treatment of simple obesity. In our study, we investigate the efficacy and related mechanism of polyglycolic acid sutures embedded in abdominal acupoints on simple obese persons by a randomized control trial.MethodsA total of 51 eligible participators were randomly allocated to a polyglycolic acid sutures embedding therapy (PASET) group (n = 28) or control group (n = 23). Participators in PASET group received polyglycolic acid sutures alternatively embedded in abdominal I group and II group acupoints in odd and even number therapeutic courses, and participators in control group were required to perform lifestyle modification. The duration of the study was 10 weeks.ResultsIt suggested that PASET significantly reduced weight, body mass index, hip circumference, waist circumference, waist/hip ratio, waist-to-height ratio and thickness of abdominal subcutaneous fat tissue compared with those before treatment (p < 0.01), but lifestyle modification only illustrated downward trend of weight (p < 0.05). Moreover, PASET group also improved the evaluated scores in aspects of physical function, self-esteem, public distress and sexual life, as well as decreased blood pressure, glycemia, low density lipoprotein, uric acid and the levels of tumor necrosis factor-alpha, interleukin-1β, and increased high density lipoprotein in comparison with those before treatment (p < 0.05), whose efficacies are superior to control group. Additionally, our results also indicate PASET is relative safe and its pain and discomfort can be tolerable.ConclusionsPASET distinctly ameliorates anthropometric data and quality of life in obese population, which associates with improvements of metabolic profile and inflammatory response. Based on the advantageous actions, we think PASET is an effective therapeutic approach to simple obesity treatment.Trial registration ChiCTR, ChiCTR1800015591. Registered 10 April 2018, http://www.chictr.org.cn/showproj.aspx?proj=23258