Total Amount Of Adipose Tissue Research Articles

Influence of Polyphenols on Adipose Tissue: Sirtuins as Pivotal Players in the Browning Process.

Adipose tissue (AT) can be classified into two different types: (i) white adipose tissue (WAT), which represents the largest amount of total AT, and has the main function of storing fatty acids for energy needs and (ii) brown adipose tissue (BAT), rich in mitochondria and specialized in thermogenesis. Many exogenous stimuli, e.g., cold, exercise or pharmacological/nutraceutical tools, promote the phenotypic change of WAT to a beige phenotype (BeAT), with intermediate characteristics between BAT and WAT; this process is called "browning". The modulation of AT differentiation towards WAT or BAT, and the phenotypic switch to BeAT, seem to be crucial steps to limit weight gain. Polyphenols are emerging as compounds able to induce browning and thermogenesis processes, potentially via activation of sirtuins. SIRT1 (the most investigated sirtuin) activates a factor involved in mitochondrial biogenesis, peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), which, through peroxisome proliferator-activated receptor γ (PPAR-γ) modulation, induces typical genes of BAT and inhibits genes of WAT during the transdifferentiation process in white adipocytes. This review article aims to summarize the current evidence, from pre-clinical studies to clinical trials, on the ability of polyphenols to promote the browning process, with a specific focus on the potential role of sirtuins in the pharmacological/nutraceutical effects of natural compounds.

Вплив фіксованої комбінації метформіну SR та глімепіриду на показники вуглеводного, ліпідного обміну та жорсткість артеріальної стінки у хворих на цукровий діабет 2-го типу

З метою вивчення впливу цукрознижувальної терапії за допомогою комбінації глімепіриду й метформіну SR упродовж 12 тижнів на показники вуглеводного й ліпідного обміну, динаміку рівня адипокінів у плазмі крові та показники жорсткості артеріальної стінки великих артерій (аорти та її гілок) спостерігали 30 пацієнтів (з них 18 — жінки) з цукровим діабетом 2-го типу віком 60,10 ± 1,08 року із серед-ньою тривалістю основного захворювання 5,7 ± 0,9 року. Результати. Порівняно з початковими значеннями відзначено покращення показників вуглеводного обміну. Так, рівень HbA1c знизився на 1,7 % (р < 0,001), глікемії натще — на 22 % (р < 0,001), постпрандіальної глікемії — на 44 % (р < 0,001). Крім того, на тлі терапії спостерігалося покращення ліпідного обміну: зниження загального холестерину на 13,2 % (р < 0,01), холестерину ліпопротеїнів низької щільності — на 19,3 % (р < 0,01), тригліцеридів — на 30,6 % (р < 0,05). Спостерігалися зміни рівня адипокінів у плазмі крові: зниження рівня адипонектину з 5,98 ± 0,52 мг/мл до 4,45 ± 0,29 мг/мл (р < 0,01), а також тенденція до збільшення рівня лептину в плазмі крові з 14,6 ± 2,3 нг/мл до 18,12 ± 2,90 нг/мл (р > 0,05). Зміни швидкості пульсової хвилі в аорті та аортального індексу аугментації були статистично незначущими (р > 0,05). Зміни антропометричних показників (ваги, індексу маси тіла, окружності талії і стегон), а також загальної кількості жирової тканини, визначеної методом імпедансометрії, були статистично незначущими (р > 0,05).Висновки. Комбінована цукрознижувальна терапія глімепіридом і метформіном SR упродовж 12 тижнів призвела до статистично значущого покращення вуглеводного та ліпідного обміну, не впливала на антропометричні показники й загальну кількість жирової тканини, запобігала прогресуванню артеріосклерозу великих судин за даними показників жорсткості артеріальної стінки.

Abdominal adipose tissue components quantification in MRI as a relevant biomarker of metabolic profile

IntroductionAbnormal accumulation of adipose tissue (AT) alters the metabolic profile and underlies cardiovascular complications. Conventional measures provide global measurements for the entire body. The purpose of this study was to propose a new approach to quantify the amount and type of truncal AT automatically from MRI in metabolic patients and controls. Materials and methodsDIXON acquisitions were performed at 1.5 T in 30 metabolic syndrome (MS) (59 ± 6 years), 12 obese (50 ± 11 years), 35 type 2 diabetes (T2DM) patients (56 ± 11 years) and 19 controls (52 ± 11 years). AT was segmented into: subcutaneous AT “SAT”, visceral AT “VAT”, deep VAT “dVAT”, peri-organ VAT “pVAT” using active contours and k-means clustering algorithms. Subsequently, organ AT infiltration index “oVAT” was calculated as the normalized fat signal magnitude in organs. ResultsExcellent intra- and inter-operator reproducibility was obtained for AT segmentation. MS and obese patients had the highest amount of total AT. SAT increased in MS (1144 ± 621 g) and T2DM patients (1024 ± 634 g), and twice the level of SAT in controls (505 ± 238 g), and further increased in obese patients (1429 ± 621 g). While VAT, pVAT and dVAT increased to a similar degree in the metabolic patients compared to controls, the oVAT index was able to differentiate controls from MS and T2DM patients and to discriminate the three metabolic patient groups (p < 0.01). Local AT sub-types were not related to BMI in all groups except for SAT in controls (p = 0.03). ConclusionReproducible truncal AT sub-types quantification using 3D MRI was able to characterize patients with metabolic diseases. It may serve in the future as a non-invasive predictor of cardiovascular complications in such patients.

Renal function and nutritional status in patients with arterial hypertension

Arterial hypertension is the main preventable cause of cardiovascular disease and all causes of death worldwide, and also ranks second among the most important causes of chronic kidney disease after diabetes. An important factor contributing to the increase in blood pressure is obesity. Being overweight raises blood pressure and accounts for 65-75% of the initial hypertension, which is the main cause of cardiovascular disease and kidney disease. The aim of the work was to study renal function in patients with arterial hypertension, depending on the nutritional status of patients. Materials and methods. A prospective study included 47 stable outpatients with stage II arterial hypertension (left ventricular hypertrophy) of the 1st to 3rd degree, (24 women and 23 men), the average age was 55.7 (8.9) years. The mean disease duration was 14 (3.2) years. The control group included 28 relatively healthy people without arterial hypertension (15 women and 9 men), the average age was 56.0 (6.6) years. All patients were evaluated for complaints, medical history, smoking status, physical examination with anthropometric indicators (height, weight, body mass index, waist circumference), heart rate and blood pressure. The risk of cardiovascular events was also determined in accordance with the SCORE scale. The nutritional status was evaluated based on bioimpedancemetry data (Omron analyzer) with determination of the percentage of total fat, muscle mass and visceral fat. To determine the functional state of the kidneys, the level of total protein in blood serum, creatinine and albumin in the urine was determined, with the determination of the albumin creatinine ratio in a single portion of urine, the glomerular filtration rate were calculated. Results and conclusions. In patients with arterial hypertension, a change in nutritional status was detected in the form of an increase in the amount of total adipose tissue against a background of a decrease in muscle tissue pool, with the development of sarcopenia in combination with obesity. Also, patients developed hypertensive nephropathy. It was found that the BMI is not informative enough to determine nutritional status, but requires the use of bioimpedancemetry to determine the percentage of total fat, visceral fat and muscle mass.

In vivo anti-obesity efficacy of curcumin loaded nanofibers transdermal patches in high-fat diet induced obese rats

Obesity as a dominant problem in developed countries which is known to be basic step of so many diseases is subjected to find a solution for in this work. Curcumin containing polyvinyl alcohol-gelatin nanofibers which ranging from 200 to 250 nm in diameter as a transdermal drug delivery system for declining volume of subcutaneous adipose tissue is investigated here. Morphology and synthesis method of nanofibers is designed and optimized by statistical software and a totally uniform and reproducible method of synthesis is used for preparation of a transdermal patch. Effectiveness of delivery system in transport of drug through skin is confirmed by side by side arrangement transdermal diffusion cells. This transdermal patch used for animal test showed 4 to 7% decrease in total amount of adipose tissue estimated by whole body magnetic resonance imaging technique.

Особливості розподілу жирової тканини у хворих на цукровий діабет 2-го типу з ожирінням та артеріальною гіпертензією з супутньою дисліпідемією

Розвиток атерогенної дисліпідемії у хворих на цукровий діабет (ЦД) 2-го типу й артеріальну гіпертензію є важливим фактором ризику серцево-судинних захворювань і часто асоціюється з ожирінням. Мета. Вивчити зв’язок між надлишковим відкладенням жиру в різних компартментах тіла зі змінами рівня ліпідів крові. Матеріали і методи. Обстежені 53 пацієнти (25 чоловіків) віком 55,90 ± 2,15 року з ЦД 2-го типу, гіпертонічною хворобою І–ІІ стадії 2-го ступеня й ожирінням І–ІІІ ступеня (45 ≥ ІМТ ≥ 30 кг/м2). Всім хворим визначався рівень ліпідів плазми крові і проводилося дослідження структури тіла за допомогою рент-генівської двофотонної абсорбціометрії з визначенням загальної маси жирової тканини (МЖТз), вмісту жиру в абдомінальній (МЖТа) і глютеофеморальній (МЖТг) ділянках. Був проведений регресійний аналіз взаємозв’язку показників ліпідного спектра й маси жирової тканини з урахуванням її розподілу. Результати. Рівень загального холестерину був статистично значимо асоційований із масою жирової тканини в абдомінальній ділянці (r = 0,27; p = 0,04). Рівень холестерину ліпопротеїдів низької щільності (ХС ЛПНЩ) був позитивно асоційований з МЖТз (r = 0,34; p = 0,01). При цьому основний внесок у цю асоціацію робив абдомінальний компартмент, бо залежність ХС ЛПНЩ від МЖТа (r = 0,38) була статистично значущою (p = 0,01). Рівень тригліцеридів був позитивно асоційований із МЖТз (r = 0,49; p = 0,001), а також з МЖТа (r = 0,39; p = 0,01) і МЖТг (r = 0,32; p = 0,02). Рівень холестерину ліпопротеїдів низької щільності (ХС ЛПВЩ) був негативно асоційований із МЖТз (r = — 0,36; p = 0,01). Висновки. У хворих із ЦД 2-го типу з ожирінням і артеріальною гіпертензією розвиток атерогенної дисліпідемії з підвищенням рівня загального холестерину, тригліцеридів і ХС ЛПНЩ, а також зі зниженням рівня ХС ЛПВЩ пов’язаний із підвищенням загальної кількості жирової тканини, а також із надлишковим відкладенням жиру в абдомінальній ділянці.

The methods for the characteristic of adipose tissue in the organism and their clinical significance

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The role of sibutramine in weight reduction

The effectiveness of pharmacologic support with sibutramine along with the preservation of dietary and regimen measures is shown in a group of long-term treated patients at the Metabolic Clinic of the University Hospital in Hradec Králové. In ambulatory patients, basic anthropometric parameters as body weight, BMI, waist circumference and the total amount of adipose tissue were compared before substitution with 10 mg sibutramine and after a four-month therapy. This group included 94 patients who were administered the same dose of sibutramine for the whole period of time. This group consisted of 37 men and 57 women. After a four-month therapy with sibutramine there was a mean reduction in weight by 7.9 ± 3.8 kg in the monitored group of patients. Their BMI was reduced by 2.3 ± 1.5 kg/height2 and the waist circumference by 4.4 ± 3.8 cm. The decrease in the percentage of the total body lipid was 2.9 %. Despite a surprising decision of the European Drug Agency to suspend the registration of sibutramine in the whole of Europe since January 2010 we can state that in our patients we have proven a positive effect of sibutramine substitution on their weight reduction (Tab. 1, Ref. 19).

Follow-up Whole-Body Assessment of Adipose Tissue Compartments during a Lifestyle Intervention in a Large Cohort at Increased Risk for Type 2 Diabetes

To assess adipose body compartments with magnetic resonance (MR) imaging and MR spectroscopy during a lifestyle intervention program that included optimized nutrition and controlled physical activity in subjects at increased risk for type 2 diabetes to determine factors that may help predict an increase in insulin sensitivity following the intervention. This prospective study was approved by the local review board. All participants gave written informed consent. MR imaging and MR spectroscopy were performed in 243 subjects (99 men and 144 women) before and 9 months after enrollment in a lifestyle intervention program. The results of whole-body MR imaging were used to calculate tissue profiles, differentiating between adipose tissue--especially visceral adipose tissue--and lean tissue. The concentration of hepatic lipids and intramyocellular lipids in the anterior tibial and soleus muscles was determined with MR spectroscopy, and insulin sensitivity was estimated by using an oral glucose tolerance test. The Student t test was used to assess differences between groups, and multivariate regression models were used to assess the value of adipose tissue compartments in the prediction of insulin sensitivity. Compared with women, men had almost twice the amount of visceral adipose tissue and a smaller amount of total adipose tissue (25.9% for men and 36.9% for women) at baseline. In addition, their insulin sensitivity was significantly lower than that of women. The most pronounced changes in adipose tissue were detected for visceral adipose tissue (from 4.9 L to 4.1 L [ie, -15.1%] in men and from 2.3 L to 1.9 L [ie, -15.8%] in women) and hepatic lipids (from 8.6% to 5.4% [ie, -36.8%] in men and from 5.1% to 4.3% [ie, -16.5%] in women). The mean insulin sensitivity improved significantly (from 11.3 arbitrary units [au] to 14.6 au [ie, +29.9%] in men and from 13.6 au to 14.6 au [ie, +7.5%] in women), with 70 of the 99 men (71%) and 84 of 144 women (58%) showing an increase in insulin sensitivity. In men, low concentrations of visceral adipose tissue, hepatic lipids, and abdominal subcutaneous fat at baseline were predictive of successful intervention in terms of changes in insulin sensitivity; in women, only low hepatic lipid levels were significantly predictive of successful intervention. Visceral adipose tissue and hepatic lipids, as assessed with MR imaging and MR spectroscopy, can be significantly reduced during lifestyle intervention. Their baseline values emerged as predictive factors for an improvement of insulin sensitivity.

FAAH deficiency promotes energy storage and enhances the motivation for food

Fatty acid amide hydrolase (FAAH) is the main degrading enzyme of the fatty acid ethanolamides anandamide (AEA) and oleoylethanolamide (OEA), which have opposite effects on food intake and energy balance. AEA, an endogenous ligand of CB(1) cannabinoid receptors, enhances food intake and energy storage, whereas OEA binds to peroxisome proliferator-activated receptors-alpha to reduce food intake and promoting lipolysis. To elucidate the role of FAAH in food intake and energy balance, we have evaluated different metabolic and behavioral responses related to feeding in FAAH-deficient (FAAH(-/-)) mice and their wild-type littermates. Total daily food intake was similar in both genotypes, but high-fat food consumption was enhanced during the dark hours and decreased during the light hours in FAAH(-/-) mice. The reinforcing and motivational effects of food were also enhanced in FAAH(-/-) mice as revealed by operant behavioral paradigms. These behavioral responses were reversed by the administration of the selective CB(1) cannabinoid antagonist rimonabant. Furthermore, body weight, total amount of adipose tissue, plasma-free fatty acids and triglyceride content in plasma, liver, skeletal muscle and adipose tissue, were increased in FAAH(-/-) mice. Accordingly, leptin levels were increased and adiponectin levels decreased in these mutants, FAAH(-/-) mice also showed enhanced plasma insulin and blood glucose levels revealing an insulin resistance. As expected, both AEA and OEA levels were increased in hypothalamus, small intestine and liver of FAAH(-/-) mice. These results indicate that the lack of FAAH predominantly promotes energy storage by food intake-independent mechanisms, through the enhancement of AEA levels rather than promoting the anorexic effects of OEA.

Practical approach for estimation of subcutaneous and visceral adipose tissue

The first objective was to investigate the correlations between anthropometrical measurements and visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in two cohorts differing in age using magnetic resonance imaging (MRI) as reference. A second objective was to investigate the potential usage of abdominal diameters in practical estimation of adipose tissue compartments using these cohorts. Measurements of body mass index, waist circumference, sagittal abdominal diameter (sagittal AD) and transverse abdominal diameter (transverse AD) were obtained from 336 volunteers of age 14-70 years. Manual measurements of VAT and SAT from single slice MRI at the L4-L5 level were used as reference. The abdominal diameters were measured from the MR images. Linear correlations between the anthropometrical measurements and the reference were studied. Sagittal AD showed the strongest correlation to VAT (r >or= 0 x 780, P<0 x 0001) and transverse AD was found to give information about the amount of SAT (r >or= 0 x 866, P<0 x 0001). The ellipse spanned by the sagittal AD and the transverse AD was strongly correlated to the total amount of adipose tissue (r >or= 0 x 962, P<0 x 0001). Strong correlations were found between sagittal and transverse abdominal diameters, assessed using MRI, and VAT and SAT, respectively. These results suggest the use of abdominal diameters in practical estimations of VAT and SAT depots.

Relationship between sex hormones, body composition and metabolic risk parameters in premenopausal women.

The metabolic complications associated with obesity are dependent upon the degree of obesity and the distribution of adipose tissue. In order to evaluate the associations between sex hormone status, metabolic risk parameters, obesity and distribution of adipose tissue, 25 premenopausal women with a wide range of body mass index (19.3-48.1 kg/m2 were studied. Body composition was determined by dual-energy x-ray absorptiometry scan and anthropometric measurements; in addition, lipid and sex hormone status were determined and an oral glucose tolerance test was performed. We found that sex hormone-binding globulin was correlated negatively with total fat mass (r = -0.77, p < 0.001) and especially with abdominal localization of adipose tissue (r = -0.85, p < 0.001). Free testosterone was correlated positively with total fat mass (r = 0.40, p < 0.05) and with abdominal fat accumulation (r = 0.64, p < 0.001). Free estrogen was correlated negatively with total amount of adipose tissue (r = -0.40, p < 0.05) but not with the distribution of adipose tissue. Finally, total fatness, abdominal localization of adipose tissue and free testosterone were all associated with elevated metabolic risk factors. However, multiple regression analysis revealed that only abdominal localization of adipose tissue was independently associated with a higher risk profile, whereas the effects of sex hormones or total fatness disappeared when abdominal localization of adipose tissue was included in the analysis. In conclusion, these findings in premenopausal women indicate that the connection between sex hormones and metabolic risk factors might be indirect, probably operating through alterations in the amount of adipose tissue in the abdominal region.

Abdominal obesity is associated with insulin resistance and reduced glycogen synthase activity in skeletal muscle

Insulin resistance is commonly associated with obesity. The present study was performed to investigate the relative importance of total fat mass versus localization of adipose tissue in insulin-stimulated glucose disposal (R d) and skeletal muscle glycogen synthase (GS) activity in obese individuals. Twenty obese women with an average body mass index (BMI) of 37.8 ± 1.3 kg/m 2 and a waist to hip ratio (WHR) ranging from 0.78 to 1.02 were examined during basal conditions and following hyperinsulinemia (hyperinsulinemic euglycemic clamp). To accurately determine body composition, the following three methods were used: anthropometric measurements, dual-energy x-ray absorptiometry scanning (DEXA-scan), and bioelectric impedance measurements. In addition, indirect calorimetry and muscle biopsy were performed. Insulin-stimulated glucose R d was negatively correlated with WHR ( R = −.52, P < .025) whereas there were no correlations with BMI or percent fat ( R = .16, NS and R = .16, NS, respectively). Furthermore, a negative correlation between WHR and insulin stimulation of GS activity in skeletal muscle was found ( R = −.62, P < .005). In contrast, BMI and percent fat were not correlated with the insulin effect on GS activity in skeletal muscle ( R = .34, NS and R = −.35, NS, respectively). The concentration of nonesterified fatty acids (NEFA) during hyperinsulineamia was strongly correlated with WHR and abdominal localization of adipose tissue (determined by DEXA-scan; R = .60, P < .005 and R = .60, P < .007, respectively). Moreover, lipid oxidation during hyperinsulinemia was positively correlated with WHR ( R = .58, P < .007), whereas there was no correlation with BMI or percent fat ( R = .31, NS and R = .29, NS, respectively). Finally, NEFA concentrations during hyperinsulinemia were negatively correlated with insulin-stimulated glucose R d ( R = .73, P < .0009). We conclude that in a group of massively obese women localization of adipose tissue in the abdominal region (assessed by various techniques) was accompanied by impaired insulin-stimulated glucose R d, decreased capacity of insulin to stimulate GS activity in skeletal muscle, and higher circulating NEFA concentrations during the hyperinsulinemic period. In contrast, no correlations between BMI, percent fat, or other measurements of total amount of adipose tissue and these variables were found. Finally, the sophisticated measurements (DEXA-scan and bioelectric measurements) were not superior to BMI and WHR in predicting insulin resistance in this group of obese women.

A weight shape index for assessing risk of disease in 44,820 women

The medical literature gives ample evidence of the relationship between obesity and specific diseases such as adult-onset diabetes and hypertension. Until recently the sole focus of the relationship has been between morbidity and the degree of overweight which is usually measured as weight relative to height. Recently we have shown that the location of body fat is not only associated with morbidity but that this relationship is independent of the total amount of adipose tissue. Clinical studies have shown that adipocyte size, location and metabolism are related to fat distribution. An excess of large fat cells in the upper body explains the increase risk of diabetes in women. The location of body fat has been used to delineate three body types: gynoid (pear shape), intermediate, and android (apple shape). We used waist girth divided by hip girth for scaling body shape and found that it is associated with morbidity after adjustment for relative weight. The use of relative weight and body shape simultaneously gives a better estimate of risk of morbidity than either alone. This study of 44,820 women presents easy to read graphs, derived from the multiple logistic model, which will permit practicing physicians to estimate visually the combined risks associated with relative weight and body fat location.