scholarly journals Metabolic role of visceral adipose tissue and main methods of its diagnosis at the present stage

2020 ◽  
Vol 82 (1) ◽  
Author(s):  
G.D. Fadieienko ◽  
Ya.V. Nikiforova
Keyword(s):  
Adipose Tissue ◽  
Visceral Adipose Tissue ◽  
Biologically Active ◽  
Inflammatory Infiltration ◽  
Endocrine Organ ◽  
Metabolic Functions ◽  
Metabolic Role ◽  
Visceral Adipose ◽  
Active Substances

A review of the literature on the metabolic role of visceral adipose tissue and the main methods for its diagnosis is presented. Visceral adipose tissue is an active endocrine organ what secretes a number of biologically active substances. With an increase in the proportion of visceral adipose tissue, moderate inflammation is observed with a chronic systemic increase in the activity of adipokines. Adipokines carry out several immune or metabolic functions associated with inflammatory infiltration. Active substances such as leptin, adiponectin, resistin, etc., the source of which is visceral adipose tissue, have peripheral, central and local effects on the metabolism of glucose and lipids, glycolysis processes in the liver, etc. It is the activity of visceral adipose tissue that should be considered among the main pathophysiological development factors obesity and its potential metabolic cardiovascular and/or liver complications.

scholarly journals Protocatechuic acids protects against high glucose- induced insulin resistance in human visceral adipose tissue

2016 ◽  
Vol 62 (5) ◽  
pp. 45-46
Author(s):  
Paulina Ormazabal ◽  
Beatrice Scazzocchio ◽  
Rosaria Varì ◽  
Annunziata Iacovelli ◽  
Roberta Masella
Keyword(s):  
Insulin Resistance ◽  
Adipose Tissue ◽  
Visceral Adipose Tissue ◽  
High Glucose ◽  
Protective Role ◽  
Insulin Sensitizer ◽  
20 Nm ◽  
Visceral Adipose

Adipocytes exposed to high glucose concentrations exhibit impaired insulin signaling. Binding of insulin to its membrane receptor activates insulin metabolic pathway leading to IRS-1 and AKT phosphorylations. The accumulation of visceral adipose tissue (VAT) correlates with insulin resistance and metabolic syndrome. Anthocyanins (ACN) are bioactive food compounds of great nutritional interest. We have shown that protocatechuic acid (PCA), a major metabolite of ACN, might exert insulin-sensitizer activities in human visceral adipose tissue. The aim of this work was to define the protective role of PCA against insulin-resistance induced by high glucose in VAT.Methodology: VAT obtained from control subject (BMI≤25) were separated in four experimental groups: i) PCA: samples treated for 24 h with 100 μM PCA, ii) GLU: VAT treated with 30 mM glucose for 24 h, iii) PCA+GLU: 1 hour incubation with 100 μM PCA before adding glucose (30 mM, 24 h), iv) CTR: vehicle. After treatment, VAT groups were (or not) acutely stimulated with insulin (20 nM, 20 min). Tyr-IRS-1 and Ser-Akt phosphorylations were assessed by Western blotting (WB) in basal or insulin stimulated tissues in all experimental groups. Samples were assessed for IRS-1, IR, Akt and GLUT4 protein content by WB. Results: No differences in protein contents between experimental groups were found. GLU tissues showed a lower increment in insulin-stimulated phosphorylation of IRS-1 and Akt compared to CTR and PCA samples. This impaired activation was completely reversed by the pretreatment with PCA.Conclusion: An in-vitro insulin-resistance condition induced by high glucose was established in biopsies of VAT. PCA restores the ability of GLU-tissues to fully respond to insulin by increasing IRS-1 and Akt phosphorylations. These results confirm the insulin-sensitizer effect of PCA on VAT previously reported by our group. An anthocyanin rich diet might help to protect against insulin-resistance in VAT.

Abstract 14315: New Insights Into the Mechanisms of Sepsis: The Role of Proprotein Convertase Subtilisin/kexin Type 9 as a Key Regulator of Pathogen Toxin Clearance

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Elena Topchiy ◽  
Yingjin Wang ◽  
John Boyd ◽  
Keith R Walley
Keyword(s):  
Adipose Tissue ◽  
Visceral Adipose Tissue ◽  
Ex Vivo ◽  
Fluorescent Microscopy ◽  
Hepatic Uptake ◽  
Cardiovascular Complications ◽  
Proprotein Convertase ◽  
Bacterial Endotoxins ◽  
Visceral Adipose

Background: To prevent severe inflammation during infection, the patient must quickly clear bacterial endotoxins from the circulation before they accumulate and are able to interact with immune cells and vascular endothelium, and induce inflammatory organ failure. Bacterial endotoxins are carried within lipoprotein particles. Thus, one mechanism of action for sepsis treatments could be acceleration of lipoprotein clearance by adipocytes and hepatocytes. Proprotein convertase subtilisin/kexin type 9 (PCSK9) decreases the rate of lipoprotein clearance. We have recently reported that reduced function of PCSK9 improves outcome and prevents cardiovascular complications associated with sepsis. Hypothesis: PCSK9 inhibits LDL associated LPS clearance through hepatic LDLR and VLDL associated LPS clearance through adipose VLDLR. Methods and Results: Using siRNA against the LDLR in HepG2 hepatocytes decreased uptake of fluorescently labeled LPS (fLPS) after 48 hours by 1.50±0.10 fold (n=3, p<0.05). Addition of recombinant PCSK9 in the absence of LDLR did not alter uptake of LPS. We confirmed that hepatic uptake of LPS is exclusively via the LDLR by fluorescent microscopy of ex vivo LPS treated primary hepatocytes isolated from LDLR -/- mice. To address the importance of the LDLR upon clearance of LPS from plasma, we injected fLPS into the portal vein of LDLR-/-, PCSK9-/- and wild type mice (WT). Compared to WT, LDLR-/- mice had 36±13% (n=9, p<0.001) increase in plasma LPS after 1 hour, whereas PCSK9-/- show a significant decrease (28±4%, n=9, p<0.001) in plasma LPS. LDLR-/-, but not PCSK9-/- mice showed 46±7% decrease (n=10, p<0.05) in hepatic uptake. On the other hand, compared to the WT PCSK9-/- mice had 200±35% (n=8, p<0.001) increase in LPS uptake by visceral adipose tissue whereas LDLR-/- had no effect compared to WT mice. To further investigate LPS uptake by adipose tissue we injected flLPS into the tail vein of VLDLR-/- and WT mice. VLDLR-/- mice had 33±6% (n=10, p<0.001) decrease in visceral adipose tissue uptake, with no significant change in hepatic uptake. Conclusions: Expression of hepatic LDLR and adipose VLDLR is mainly regulated by PCSK9 and both play important role in clearing LPS from circulation.

scholarly journals COVID-19 and Obesity: Role of Ectopic Visceral and Epicardial Adipose Tissues in Myocardial Injury

2021 ◽  
Vol 12 ◽  
Author(s):  
Adèle Lasbleiz ◽  
Bénédicte Gaborit ◽  
Astrid Soghomonian ◽  
Axel Bartoli ◽  
Patricia Ancel ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Intensive Care ◽  
Inflammatory Cytokines ◽  
Visceral Adipose Tissue ◽  
Cardiovascular Events ◽  
Low Grade ◽  
Viral Spread ◽  
Visceral Adipose ◽  
Pro Inflammatory Cytokines

In March 2020, the WHO declared coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a global pandemic. Obesity was soon identified as a risk factor for poor prognosis, with an increased risk of intensive care admissions and mechanical ventilation, but also of adverse cardiovascular events. Obesity is associated with adipose tissue, chronic low-grade inflammation, and immune dysregulation with hypertrophy and hyperplasia of adipocytes and overexpression of pro-inflammatory cytokines. However, to implement appropriate therapeutic strategies, exact mechanisms must be clarified. The role of white visceral adipose tissue, increased in individuals with obesity, seems important, as a viral reservoir for SARS-CoV-2 via angiotensin-converting enzyme 2 (ACE2) receptors. After infection of host cells, the activation of pro-inflammatory cytokines creates a setting conducive to the “cytokine storm” and macrophage activation syndrome associated with progression to acute respiratory distress syndrome. In obesity, systemic viral spread, entry, and prolonged viral shedding in already inflamed adipose tissue may spur immune responses and subsequent amplification of a cytokine cascade, causing worse outcomes. More precisely, visceral adipose tissue, more than subcutaneous fat, could predict intensive care admission; and lower density of epicardial adipose tissue (EAT) could be associated with worse outcome. EAT, an ectopic adipose tissue that surrounds the myocardium, could fuel COVID-19-induced cardiac injury and myocarditis, and extensive pneumopathy, by strong expression of inflammatory mediators that could diffuse paracrinally through the vascular wall. The purpose of this review is to ascertain what mechanisms may be involved in unfavorable prognosis among COVID-19 patients with obesity, especially cardiovascular events, emphasizing the harmful role of excess ectopic adipose tissue, particularly EAT.

scholarly journals Significant role of fat tissue hormones in development of comorbid chronic pancreatitis and obesity

2018 ◽  
Vol 39 (1) ◽  
pp. 4-9
Author(s):  
T. N. Hristich
Keyword(s):  
Type 2 Diabetes ◽  
Adipose Tissue ◽  
Chronic Pancreatitis ◽  
Visceral Adipose Tissue ◽  
Healthy Lifestyle ◽  
Pancreatic Disease ◽  
Pancreatic Tissue ◽  
Visceral Adipose

Aim is to consider the role of hormones in the adipose tissue of obesity mechanisms of metabolic syndrome, type 2 diabetes mellitus in chronic pancreatitis. Materials and methods. Literature review indicates the value of visceral fat in the development of insulin resistance, dyslipidemia, including atherogenic one, taking into account the possible infiltration of pancreatic tissue by adipocytes. Participation of some adipocytokines of adipose tissue in the development of obesity in chronic pancreatitis is highlighted. It is shown that in some cases the hormones of visceral adipose tissue, penetrating through the portal vein to the liver and then to the pancreas, aggravated the course of systemic chronic inflammation typical for the inherent chronic pancreatitis, formed steatosis and promoted development of fatty disease of the pancreas. Conclusion. Literary sources show the leading role of visceral adipose tissue and its hormones in the formation of obesity in chronic pancreatitis. Lipoidosis or steatosis develop due to the infiltration of the liver and pancreatic tissue by adipocytes. Upon the progression of the type 2 diabetes, fatty liver or pancreatic disease, or cancer of these organs may develop. Consequently, there is a strong need for a serious differentiated preventive and curative measures aimed at promoting a healthy lifestyle to improve the quality of life of patients suffering from chronic pancreatitis.

scholarly journals Steroid sulfatase activity in subcutaneous and visceral adipose tissue: a comparison between pre- and postmenopausal women

2016 ◽  
Vol 174 (2) ◽  
pp. 167-175 ◽  
Author(s):  
Hanna Paatela ◽  
Feng Wang ◽  
Veera Vihma ◽  
Hanna Savolainen-Peltonen ◽  
Tomi S Mikkola ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Postmenopausal Women ◽  
Visceral Adipose Tissue ◽  
Premenopausal Women ◽  
Biologically Active ◽  
Tissue Homogenate ◽  
Steroid Sulfatase ◽  
Peripheral Tissues ◽  
Sulfatase Activity ◽  
Visceral Adipose

ObjectiveAdipose tissue is an important extragonadal site for steroid hormone biosynthesis. After menopause, estrogens are synthesized exclusively in peripheral tissues from circulating steroid precursors, of which the most abundant is dehydroepiandrosterone sulfate (DHEAS). Our aim was to study activity of steroid sulfatase, an enzyme hydrolyzing DHEAS, and expression of steroid-converting enzyme genes in subcutaneous and visceral adipose tissue derived from pre- and postmenopausal women.DesignSerum and paired abdominal subcutaneous and visceral adipose tissue samples were obtained from 18 premenopausal and seven postmenopausal women undergoing elective surgery for non-malignant reasons in Helsinki University Central Hospital.MethodsTo assess steroid sulfatase activity, radiolabeled DHEAS was incubated in the presence of adipose tissue homogenate and the liberated dehydroepiandrosterone (DHEA) was measured. Gene mRNA expressions were analyzed by quantitative RT-PCR. Serum DHEAS, DHEA, and estrogen concentrations were determined by liquid chromatography–tandem mass spectrometry.ResultsSteroid sulfatase activity was higher in postmenopausal compared to premenopausal women in subcutaneous (median 379 vs 257 pmol/kg tissue per hour; P=0.006) and visceral (545 vs 360 pmol/kg per hour; P=0.004) adipose tissue. Visceral fat showed higher sulfatase activity than subcutaneous fat in premenopausal (P=0.035) and all (P=0.010) women. The mRNA expression levels of two estradiol-producing enzymes, aromatase and 17β-hydroxysteroid dehydrogenase type 12, were higher in postmenopausal than in premenopausal subcutaneous adipose tissue.ConclusionsSteroid sulfatase activity in adipose tissue was higher in postmenopausal than in premenopausal women suggesting that DHEAS, derived from the circulation, could be more efficiently utilized in postmenopausal adipose tissue for the formation of biologically active sex hormones.

scholarly journals Role of ceramide-to-dihydroceramide ratios for insulin resistance and non-alcoholic fatty liver disease in humans

2020 ◽  
Vol 8 (2) ◽  
pp. e001860
Author(s):  
Maria Apostolopoulou ◽  
Ruth Gordillo ◽  
Sofiya Gancheva ◽  
Klaus Strassburger ◽  
Christian Herder ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Adipose Tissue ◽  
Visceral Adipose Tissue ◽  
Fatty Liver Disease ◽  
Liver Fat ◽  
Liver Fat Content ◽  
Alcoholic Fatty Liver ◽  
Visceral Adipose ◽  
Alcoholic Fatty Liver Disease

IntroductionSphingolipid accumulation has been linked to obesity, type 2 diabetes and non-alcoholic fatty liver disease (NAFLD). A recent study showed that depletion of dihydroceramide desaturase-1 (DES-1) in adipose and/or liver tissue decreases ceramide-to-dihydroceramide ratios (ceramide/dihydroceramide) in several tissues and improves the metabolic profile in mice. We tested the hypothesis that ceramide/dihydroceramide would also be elevated and relate positively to liver fat content and insulin resistance in humans.Research design and methodsThus, we assessed total and specific ceramide/dihydroceramide in various biosamples of 7 lean and 21 obese volunteers without or with different NAFLD stages, who were eligible for abdominal or bariatric surgery, respectively. Biosamples were obtained from serum, liver, rectus abdominis muscle as well as subcutaneous abdominal and visceral adipose tissue during surgery.ResultsSurprisingly, certain serum and liver ceramide/dihydroceramide ratios were reduced in both obesity and non-alcoholic steatohepatitis (NASH) and related inversely to liver fat content. Specifically, hepatic ceramide/dihydroceramide (species 16:0) related negatively to hepatic mitochondrial capacity and lipid peroxidation. In visceral adipose tissue, ceramide/dihydroceramide (species 16:0) associated positively with markers of inflammation.ConclusionThese results failed to confirm the relationships of ceramide/dihydroceramide in humans with different degree of insulin resistance. However, the low hepatic ceramide/dihydroceramide favor a role for dihydroceramide accumulation in NASH, while a specific ceramide/dihydroceramide ratio in visceral adipose tissue suggests a role of ceramides in obesity-associated low-grade inflammation.

Sign in / Sign up

Export Citation Format

Share Document