Inhibition of leptin-induced vascular extracellular matrix remodelling by adiponectin

CRISPR/Cas9-mediated deletion of adipocyte genes associated with NAFLD alters adipocyte lipid handling and reduces steatosis in hepatocytes in vitro

Obesity is a major risk factor for the development of nonalcoholic fatty liver disease (NAFLD), and the subcutaneous white adipose tissue (scWAT) is the primary lipid storage depot and regulates lipid fluxes to other organs. Our previous work identified genes upregulated in scWAT of patients with NAFLD: SOCS3, DUSP1, and SIK1. Herein, we knocked down (KD) their expression in human adipose-derived mesenchymal stem cells (hADMSCs) using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology and characterized their phenotype. We found that SOCS3, DUSP1, and SIK1 expression in hADMSC-derived adipocytes was not critical for adipogenesis. However, the metabolic characterization of the cells suggested that the genes played important roles in lipid metabolism. Reduction of SIK1 expression significantly increased both de novo lipogenesis (DNL) and palmitate-induced lipogenesis (PIL). Editing out SOCS3 reduced DNL while increasing isoproterenol-induced lipolysis and insulin-induced palmitate accumulation. Conversely, DUSP1 reduced PIL and DNL. Moreover, RNA-sequencing analysis of edited cells showed that these genes not only altered lipid metabolism but also other biological pathways related to inflammatory processes, in the case of DUSP1, extracellular matrix remodeling for SOCS3, or cellular transport for SIK1. Finally, to evaluate a possible adipocyte-hepatocyte axis, human hepatoma HepG2 cells were cocultured with edited hADMSCs-derived adipocytes in the presence of [3H]-palmitate. All HepG2 cells cultured with DUSP1-, SIK1-, or SOCS3-KD adipocytes decreased [3H]-palmitate accumulation compared with control adipocytes. These results support our hypotheses that SOCS3, DUSP1, and SIK1 regulate multiple aspects of adipocyte function, which may play a role in the progression of obesity-associated comorbidities, such as NAFLD.NEW & NOTEWORTHY Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology successfully edited genomic DNA of human adipose-derived mesenchymal stem cells (hADMSC). SOCS3, SIK1, and DUSP1 regulate adipocyte lipid handling. Silencing SOCS3, SIK1, and DUSP1 expression in hADMSC-derived adipocytes reduces hepatocyte lipid storage in vitro.

Role of Leptin and Adiponectin in Carcinogenesis

Hormones produced by adipocytes, leptin and adiponectin, are associated with the process of carcinogenesis. Both of these adipokines have well-proven oncologic potential and can affect many aspects of tumorigenesis, from initiation and primary tumor growth to metastatic progression. Involvement in the formation of cancer includes interactions with the tumor microenvironment and its components, such as tumor-associated macrophages, cancer-associated fibroblasts, extracellular matrix and matrix metalloproteinases. Furthermore, these adipokines participate in the epithelial-mesenchymal transition and connect to angiogenesis, which is critical for cancer invasiveness and cancer cell migration. In addition, an enormous amount of evidence has demonstrated that altered concentrations of these adipocyte-derived hormones and the expression of their receptors in tumors are associated with poor prognosis in various types of cancer. Therefore, leptin and adiponectin dysfunction play a prominent role in cancer and impact tumor invasion and metastasis in different ways. This review clearly and comprehensively summarizes the recent findings and presents the role of leptin and adiponectin in cancer initiation, promotion and progression, focusing on associations with the tumor microenvironment and its components as well as roles in the epithelial-mesenchymal transition and angiogenesis.

Adipose Tissue Paracrine-, Autocrine-, and Matrix-Dependent Signaling during the Development and Progression of Obesity

Obesity is an ever-increasing phenomenon, with 42% of Americans being considered obese (BMI ≥ 30) and 9.2% being considered morbidly obese (BMI ≥ 40) as of 2016. With obesity being characterized by an abundance of adipose tissue expansion, abnormal tissue remodeling is a typical consequence. Importantly, this pathological tissue expansion is associated with many alterations in the cellular populations and phenotypes within the tissue, lending to cellular, paracrine, mechanical, and metabolic alterations that have local and systemic effects, including diabetes and cardiovascular disease. In particular, vascular dynamics shift during the progression of obesity, providing signaling cues that drive metabolic dysfunction. In this review, paracrine-, autocrine-, and matrix-dependent signaling between adipocytes and endothelial cells is discussed in the context of the development and progression of obesity and its consequential diseases, including adipose fibrosis, diabetes, and cardiovascular disease.

The emerging role of leptin in obesity-associated cardiac fibrosis: evidence and mechanism

Cardiac fibrosis is a hallmark of various cardiovascular diseases, which is quite commonly found in obesity, and may contribute to the increased incidence of heart failure arrhythmias, and sudden cardiac death in obese populations. As an endogenous regulator of adiposity metabolism, body mass, and energy balance, obesity, characterized by increased circulating levels of the adipocyte-derived hormone leptin, is a critical contributor to the pathogenesis of cardiac fibrosis. Although there are some gaps in our knowledge linking leptin and cardiac fibrosis, this review will focus on the interplay between leptin and major effectors involved in the pathogenesis underlying cardiac fibrosis at both cellular and molecular levels based on the current reports. The profibrotic effect of leptin is predominantly mediated by activated cardiac fibroblasts but may also involve cardiomyocytes, endothelial cells, and immune cells. Moreover, a series of molecular signals with a known profibrotic property is closely involved in leptin-induced fibrotic events. A more comprehensive understanding of the underlying mechanisms through which leptin contributes to the pathogenesis of cardiac fibrosis may open up a new avenue for the rapid emergence of a novel therapy for preventing or even reversing obesity-associated cardiac fibrosis.

Adipokines and Arterial Stiffness in Obesity

Adipokines are active molecules with pleiotropic effects produced by adipose tissue and involved in obesity-related metabolic and cardiovascular diseases. Arterial stiffness, which is a consequence of arteriosclerosis, has been shown to be an independent predictor of cardiovascular morbidity and mortality. The pathogenesis of arterial stiffness is complex but incompletely understood. Adipokines dysregulation may induce, by various mechanisms, vascular inflammation, endothelial dysfunction, and vascular remodeling, leading to increased arterial stiffness. This article summarizes literature data regarding adipokine-related pathogenetic mechanisms involved in the development of arterial stiffness, particularly in obesity, as well as the results of clinical and epidemiological studies which investigated the relationship between adipokines and arterial stiffness.

Leptin in Atherosclerosis: Focus on Macrophages, Endothelial and Smooth Muscle Cells

Increasing adipose tissue mass in obesity directly correlates with elevated circulating leptin levels. Leptin is an adipokine known to play a role in numerous biological processes including regulation of energy homeostasis, inflammation, vascular function and angiogenesis. While physiological concentrations of leptin may exhibit multiple beneficial effects, chronically elevated pathophysiological levels or hyperleptinemia, characteristic of obesity and diabetes, is a major risk factor for development of atherosclerosis. Hyperleptinemia results in a state of selective leptin resistance such that while beneficial metabolic effects of leptin are dampened, deleterious vascular effects of leptin are conserved attributing to vascular dysfunction. Leptin exerts potent proatherogenic effects on multiple vascular cell types including macrophages, endothelial cells and smooth muscle cells; these effects are mediated via an interaction of leptin with the long form of leptin receptor, abundantly expressed in atherosclerotic plaques. This review provides a summary of recent in vivo and in vitro studies that highlight a role of leptin in the pathogenesis of atherosclerotic complications associated with obesity and diabetes.

Effects of carotid baroreceptor stimulation on aortic remodeling in obese rats

BACKGROUND AND AIM

Our previous study found carotid baroreceptor stimulation (CBS) reduces body weight and white adipose tissue (WAT) weight, restores abnormal secretion of adipocytokines and inflammation factors, decreases systolic blood pressure (SBP) by inhibiting activation of sympathetic nervous system (SNS) and renin-angiotensin system (RAS) in obese rats. In this study, we explore effects of CBS on aortic remodeling in obese rats.

METHODS AND RESULTS

Rats were fed high-fat diet (HFD) for 16 weeks to induce obesity and underwent either CBS device implantation and stimulation or sham operation at 8 weeks. BP and body weight were measured weekly. RAS activity of WAT, histological, biochemical and functional profiles of aortas were detected after 16 weeks. CBS effectively decreased BP in obese rats, downregulated mRNA expression of angiotensinogen (AGT) and renin in WAT, concentrations of AGT, renin, angiotensin II (Ang II), protein levels of Ang II receptor 1 (AT1R) and Ang II receptor 2 (AT2R) in WAT were declined. CBS inhibited reactive oxygen species (ROS) generation, inflammatory response and endoplasmic reticulum (ER) stress in aortas of obese rats, restrained vascular wall thickening and vascular smooth muscle cells (VSMCs) phenotypic switching, increased nitric oxide (NO) synthesis, promoted endothelium-dependent vasodilatation by decreasing protein expression of AT1R and leptin receptor (LepR), increasing protein expression of adiponectin receptor 1 (AdipoR1) in aortic VSMCs.

CONCLUSION

CBS reduced BP and reversed aortic remodeling in obese rats, the underlying mechanism might be related to the suppressed SNS activity, restored adipocytokine secretion and restrained RAS activity of WAT.

Regulation and function of leptin during ovarian follicular development in cows

Although it is well documented that leptin signals the body nutritional status to the brain, mechanisms of leptin regulation at the ovary are not well understood. This study was conducted to determine whether there was leptin and the receptor for leptin (LEPR) in cattle ovarian follicles and to investigate potential actions of leptin on follicular growth in vivo and on regulation of granulosa cell functions in vitro. There was leptin and LEPR in granulosa and theca cells of dominant and subordinate follicles, with greater immunostaining for leptin in granulosa cells of subordinate follicles. There was a lesser relative abundance of leptin receptor gene-related protein (LEPROT) and of the adiponectin receptors 1 (ADIPOR1) and 2 (ADIPOR2) mRNA transcripts in granulosa cells of subordinate than dominant follicles (P < 0.05). Intrafollicular injection of either 100 or 1000 ng/mL leptin did not affect the diameter and the growth of dominant follicles (P> 0.05). Supplementation of in vitro culture medium with different leptin concentations did not affect (P > 0.05) the relative abundance of hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 1 (HSD3B1), cytochrome P450 family 11 subfamily A member 1 (CYP11A1), signal transducer and activator of transcription 3 (STAT3) and X-linked inhibitor of apoptosis protein (XIAP) mRNA transcripts in granulosa cells. These findings indicate that leptin and LEPR are present in the follicular cells of cattle ovaries, but leptin apparently does not have essential functions in steroidogenesis and growth of dominant follicles.

Adipokines and Arterial Stiffness in the Elderly

INTRODUCTION

The aim of this study was to evaluate the relationship between adipokines and arterial stiffness in a group of 85 elderly subjects and the role of leptin and adiponectin on subclinical vascular damage, defined by a PWV>10 m/s.

METHODS

In each subject, we evaluated anthropometry, body composition by DXA (fat mass, fat mass%, lean mass), metabolic variables, leptin, adiponectin, systolic, diastolic, mean arterial pressure and pulse pressure (SBP, DBP, MAP, PP), carotid-femoral pulse wave velocity (cfPWV) and carotid-radial pulse wave velocity (crPWV).

RESULTS

In the study population, significant associations were observed between cfPWV and crPWV, age, SBP, MAP, waist circumference, fat body mass and leptin. The study population was subdivided in 2 subgroups according to adipokine patterns: group 1 included patients with high adiponectin and low leptin, and group 2 patients had high leptin and low adiponectin. SBP, PP, cfPWV were significantly higher in subjects with high leptin and low adiponectin (group 2). Even after adjustment for gender, fat mass%, MAP, HDL cholesterol and triglycerides, cfPWV was higher in group 2 than group 1. In a logistic binary regression on the entire population, considering subclinical vascular damage as a dependent variable and age, gender, MAP, fat mass%, triglycerides, HDL cholesterol and category of subjects with high leptin and low adiponectin as independent variables, MAP and category of subjects with high leptin and low adiponectin were significant predictors (OR, respectively, 1.09 and 3.61).

CONCLUSION

In conclusion, in the elderly, the presence at the same time of high leptin levels and low adiponectin levels seems to have synergic effects on arterial stiffness.

Advances in understanding the role of adiponectin in renal fibrosis

Renal fibrosis is characterized by the proliferation of renal intrinsic cells, activation of renal interstitial fibroblasts and deposition of extracellular matrix (ECM), processes that lead to the progressive loss of renal function. Renal fibrosis is characterized by the proliferation of renal intrinsic cells, activation of renal interstitial fibroblasts, and septal fibrosis is recognized as a marker for the progression of chronic kidney disease, a condition that is associated with high morbidity and mortality and is a significant public health burden. Despite extensive studies, there are no effective treatments for renal fibrosis. Adiponectin (APN) is a protein mainly produced by adipocytes that has anti-inflammatory and anti-atherosclerotic effects, improves insulin resistance and provides other salutary effects. Recent studies found that APN can inhibit ECM deposition by inhibiting inflammation and oxidative stress, and by regulating the TGF-β, AMPK, MCP-1 and other signalling pathways. Many recent studies have examined the roles of these pathways in the pathogenesis of renal fibrosis. In this article, we review the pathogenic mechanism of APN in renal fibrosis and provide a theoretical basis for delaying and blocking renal fibrosis by alteration of APN activity.

Knockdown of CTCF reduces the binding of EZH2 and affects the methylation of the SOCS3 promoter in hepatocellular carcinoma

The epigenetic silencing mechanism of suppressor 3 of cytokine signaling (SOCS3) in cancers has not been fully elucidated. Polycomb repressive complexes 2 (PRC2), an important epigenetic regulatory factors, exerts a critical role in repressing the initial phase of gene transcription. Whether PRC2 participates the down- regulation of SOCS3 in Hepatocellular carcinoma (HCC) remains unclear and how does PRC2 be recruited target gene still needs to explore. In this study, Using TCGA HCC dataset, and detecting HCC tissue specimens and cell lines, we found that SOCS3 expression in HCC was inversely related to that of EZH2, and depended on its promoter methylation status. CTCF, vigilin, EZH2 and H3K27me3 were enriched at CTCF and EZH2 binding sites on the methylated SOCS3 gene promoter. The depletion of CTCF did not affect expression of EZH2 and DNMT1, but decrease recruitment of CTCF, vigilin, EZH2 and H3K27me3. Further, knockdown of CTCF led to a loss of methylation of the methylated SOCS3 promoter, which sequentially increased the expression of SOCS3 and decreased the expression of pSTAT3, the downstream effector. These findings suggest that the CTCF dependent recruitment of EZH2 to the SOCS3 gene promoter is likely to participate in the epigenetic silencing of SOCS3 and in regulating its gene expression.

Serum leptin, a potential predictor of long-term angiographic progression in Takayasu's arteritis

Aim

In patients with Takayasu's arteritis (TA), current biomarkers that properly reflect the progression of the vascular structure remain absent. We aimed to determine the serum leptin level to investigate its relationship with imaging changes and assess its value as a predictor for long‐term radiological progression.

Method

This study included 34 untreated TA patients and 40 age‐matched healthy controls. At baseline and during the 5‐year follow‐up, we assessed disease activity using Kerr's criteria and Indian Takayasu Clinical Activity Score (ITAS2010) and monitored laboratory biomarkers as well as imaging findings. Serum leptin levels were measured by enzyme‐linked immunosorbent assay.

Results

The baseline serum leptin levels were significantly higher in TA patients than in healthy controls. Leptin was significantly positively correlated with triglyceride and high‐density lipoprotein cholesterol levels and negatively correlated with fibrinogen and C‐reactive protein levels. Patients were subdivided into three groups based on their baseline leptin level. During a 5‐year follow‐up, patients in the high and medium leptin groups showed more radiological progression compared to those in the low leptin group. Cox proportional hazard regression analysis showed that a high serum leptin level was a positive predictor of radiological progression.

Conclusion

Leptin is a potential biomarker for assessing TA structural progression. Untreated patients with elevated serum leptin levels are at a higher risk of progression in the aorta. Thus, the leptin level can be a predictor of long‐term radiological progression.

Leptin and adiponectin dynamics at patients with rectal neoplasm - Gender differences

Background

Numerous studies associate adipokines with colorectal malignancy, but few data deal with patients suffering exclusively of rectal carcinoma (RC).

Aims

We evaluated leptin and adiponectin levels in RC patients compared to healthy population and their dynamics after surgery.

Material and methods

Serum leptin and adiponectin were evaluated before surgery in 59 RC consecutive patients (38 males and 21 females), and in age and weight matched healthy controls. Measurements were repeated at 24, 72 hours and 7 days after surgery.

Results

Adipokine levels were higher in women. Controls had higher leptin (32.±4.34 vs 9.51±1.73 ng/ml in women and 11±2.66 vs 2.54±0.39 ng/ml in men, p = 0.00048 and 0.0032) and lower adiponectin (9±0.64 vs 11.85±1.02 μg/ml in women and 7.39±0.51 vs 8.5±0.62 μg/ml in men, p = 0.017 and 0.019) than RC patients. Surgery caused an increase of leptin from 5.11±0.8 to 18.7±2.42 ng/ml, p = 6.85 x 10¨⁸, and a decrease of adiponectin from 9.71±0.58 to 7.87±0.47 μg/ml, p = 1.4 x 10¨¹⁰ for all RC patients and returned thereafter to the initial range at 7 days. Adipokines were correlated with body weight (BW). The significance of correlation persisted after surgery only in males, but disappeared in females. Adipokines were not modified by tumor position, presurgical chemoradiotherapy or surgical technique. Women with RC experiencing weight loss had higher adiponectin than women without weight modifications (p<0.05 at all time points).

Conclusions

Adipokine levels of patients with RC differ from the healthy population, possibly reflecting an adaptation to disease. Adipokine modifications after surgery may be related to acute surgical stress. Whether leptin and adiponectin directly interact is not clear. Women have higher adipokine levels, more so after significant weight loss, but the strength of their correlation with BW decreases after surgery. These data suggest gender differences in the adipokine profile of RC patients which may find clinical applications.

Sijunzi decoction may decrease apoptosis via stabilization of the extracellular matrix following cerebral ischaemia-reperfusion in rats

Neurons undergo degeneration, apoptosis and death due to ischaemic stroke. The present study investigated the effect of Sijunzi decoction (SJZD), a type of traditional Chinese medicine known as invigorating spleen therapy, on anoikis (a type of apoptosis) in rat brains following cerebral ischaemia-reperfusion. Rats were randomly divided into sham, model, nimodipine and SJZD low/medium/high dose groups. A middle cerebral artery occlusion model was established. Neurobehavioural scores were evaluated after administration for 14 days using a five-grade scale. Blood-brain barrier permeability and apoptotic rate were detected using Evans blue (EB) extravasation and TUNEL staining, respectively. Tissue inhibitor of metalloproteinase 1 (TIMP-1), matrix metalloproteinase 9 (MMP-9) and collagen IV (COL IV) were determined using immunohistochemistry. Neurobehavioural scores decreased remarkably in all SJZD and nimodipine groups compared to the model group (P<0.05). Compared with the sham group, EB extravasation was higher in the model group (P<0.01). The amount of EB extravasation decreased in the SJZD high dose and nimodipine groups compared to the model group (P<0.01), and extravasation in the SJZD high dose group was lower than the SJZD low and medium dose groups (P<0.01). TIMP-1 and MMP-9 expression and apoptotic rate increased, but COL IV decreased significantly in the hippocampus of the model group compared to the sham group (P<0.01). TIMP-1 and COL IV expression increased significantly and MMP-9 and apoptotic rate decreased remarkably in all SJZD and nimodipine groups compared to the model group (P<0.01). TIMP-1 and COL IV expression decreased, but MMP-9 expression and apoptotic rate increased in the SJZD low and medium dose groups compared to the SJZD high dose group (P<0.01). SJZD rescued neurons and improved neurobehavioural function in rats following cerebral ischaemia-reperfusion, especially when used at a high dose. The mechanism may be related to protection of the extracellular matrix followed by anti-apoptotic effects.

AdipoRs- a potential therapeutic target for fibrotic disorders

Introduction: Fibrotic disorders are a leading cause of morbidity and mortality; hence effective treatments are still vigorously sought. AdipoRs (AdipoR1 and Adipo2) are responsible for the antifibrotic effects of adiponectin (APN). APN exerts antifibrotic effects by binding to its receptors. APN concentration and AdipoR expression are closely associated with fibrotic disorders. Decreased AdipoR expression may reduce APN-AdipoR signaling, while the upregulation of AdipoR expression may restore the anti-fibrotic effects of APN. Loss of APN signaling exacerbates fibrosis in vivo and in vitro. Areas covered: We assess the relationship between APN and fibrotic disorders, the structure of receptors for APN and the pathways accounting for APN or its analogs blocking fibrotic disorders. This article also discusses designed APN products and their therapeutic prospects for fibrotic disorders. Expert opinion: AdipoRs have a critical role in blocking fibrosis. The development of small-molecule agonists toward this target represents a valid drug development pathway.

The aging heart

As the elderly segment of the world population increases, it is critical to understand the changes in cardiac structure and function during the normal aging process. In this review, we outline the key molecular pathways and cellular processes that underlie the phenotypic changes in the heart and vasculature that accompany aging. Reduced autophagy, increased mitochondrial oxidative stress, telomere attrition, altered signaling in insulin-like growth factor, growth differentiation factor 11, and 5'- AMP-activated protein kinase pathways are among the key molecular mechanisms underlying cardiac aging. Aging promotes structural and functional changes in the atria, ventricles, valves, myocardium, pericardium, the cardiac conduction system, and the vasculature. We highlight the factors known to accelerate and attenuate the intrinsic aging of the heart and vessels in addition to potential preventive and therapeutic avenues. A greater understanding of the processes involved in cardiac aging may facilitate our ability to mitigate the escalating burden of CVD in older individuals and promote healthy cardiac aging.

AMPK orchestrates an elaborate cascade protecting tissue from fibrosis and aging

Fibrosis is a common process characterized by excessive extracellular matrix (ECM) accumulation after inflammatory injury, which is also a crucial cause of aging. The process of fibrosis is involved in the pathogenesis of most diseases of the heart, liver, kidney, lung, and other organs/tissues. However, there are no effective therapies for this pathological alteration. Annually, fibrosis represents a huge financial burden for the USA and the world. 5'-AMP-activated protein kinase (AMPK) is a pivotal energy sensor that alleviates or delays the process of fibrogenesis. In this review, we first present basic background information on AMPK and fibrogenesis and describe the protective roles of AMPK in three fibrogenic phases. Second, we analyze the protective action of AMPK during fibrosis in myocardial, hepatic, renal, pulmonary, and other organs/tissues. Third, we present a comprehensive discussion of AMPK during fibrosis and draw a conclusion. This review highlights recent advances, vital for basic research and clinical drug design, in the regulation of AMPK during fibrosis.

The roles of signal transducer and activator of transcription factor 3 in tumor angiogenesis

Angiogenesis is the development of new blood vessels, which is required for tumor growth and metastasis. Signal transducer and activator of transcription factor 3 (STAT3) is a transcription factor that regulates a variety of cellular events including proliferation, differentiation and apoptosis. Previous studies revealed that activation of STAT3 promotes tumor angiogenesis. In this review, we described the activities of STAT3 signaling in different cell types involved in angiogenesis. Particularly, we elucidated the molecular mechanisms of STAT3-mediated gene regulation in angiogenic endothelial cells in response to external stimulations such as hypoxia and inflammation. The potential for STAT3 as a therapeutic target was also discussed. Overall, this review provides mechanistic insights for the roles of STAT3 signaling in tumor angiogenesis.

Prognostic Value of Adipokines in Predicting Cardiovascular Outcome: Explaining the Obesity Paradox

OBJECTIVE

To evaluate the cardiovascular (CV) prognostic value of adipokines in a large prospective cohort of patients participating in the Bypass Angioplasty Revascularization Investigation 2 Diabetes trial.

PATIENTS AND METHODS

The effects of the adipokine levels at baseline and change from baseline on the composite outcome (CV death, myocardial infarction, and stroke) were analyzed using unadjusted and fully adjusted Cox models in 2330 patients with type 2 diabetes and coronary artery disease who had participated in the Bypass Angioplasty Revascularization Investigation 2 Diabetes trial (from January 1, 2001, through December 1, 2008).

RESULTS

In a fully adjusted model, baseline leptin and change from baseline leptin were protective for CV events, whereas baseline adiponectin, baseline tumor necrosis factor α (TNF-α), change from baseline TNF-α, baseline C-reactive protein (CRP), and change from baseline CRP were harmful. The effect of baseline leptin on CV events depended on the body mass index (BMI), such that the hazard ratios (HRs) varied between 0.6 and 1.4 across the BMI quintiles (interaction P=.03). The same was true for baseline adiponectin (HR varied from 0.7 to 1.7; interaction P=.01), change from baseline monocyte chemoattractant protein-1 (HR varied from 0.8 to 1.8; interaction P=.03), change from baseline TNF-α (HR varied from 0.9 to 1.4; interaction P=.02), and change from baseline IL-6 (HR varied from 0.7 to 1.8; interaction P=.005).

CONCLUSION

Adipokines are independent predictors of CV events in patients with type 2 diabetes and coronary artery disease. The association between the specific adipokines and CV outcome varies depending on BMI. This reflects the complex pathophysiology of CV disease in obesity and may help explain the "obesity paradox."

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00006305.

Variation in blood levels of hormones in obese patients following weight reduction induced by endoscopic and surgical bariatric therapies

BACKGROUND

Beneficial clinical effects of weight reduction following bariatric therapies is not fully understood and maybe related to the complex interactions between leptin, adiponectin, visfatin, omentin, and ghrelin. The aim of study was to investigate their timeline changes associated with weight reduction and their profile in relation to the type of treatment and its efficacy.

METHODS

Circulating hormones levels were analyzed before and after endoscopic and surgical procedures in 67 obese patients and compared to non-obese healthy controls.

RESULTS

Obese patients had higher leptin levels and lower levels of adiponectin, visfatin, omentin, and ghrelin than non-obese controls. During the consecutive follow-up visits after treatment, there was a gradual decrease in leptin levels and an increase in adiponectin levels to the levels observed in non-obese. At 50-54weeks, the ghrelin levels were lower and the levels of adiponectin and visfatin, but not omentin, were higher compared to their baseline values. BMI correlated with ghrelin and leptin levels. The percentage of total weight loss correlated positively with adiponectin levels and negatively with leptin levels. Patients with adequate weight loss had a significantly lower leptin concentration than those with treatment failure. There were timeline variations in hormone levels between endoscopic and bariatric therapies, however there were no significant differences in the median their concentration at 50-54weeks after therapy.

CONCLUSION

Our study supports observations that weight loss itself, rather than the procedure type, is responsible for hormonal variation. The leptin levels reflect the best the body weight changes after bariatric therapies.

Adiponectin as an anti-fibrotic and anti-inflammatory adipokine in the liver

Hepatic fibrosis is a dynamic process resulting from excessive deposition of extracellular matrix in the liver; uncontrolled progression of fibrosis can eventually lead to liver cirrhosis and/or hepatocellular carcinoma. The fibrogenic process is complex and modulated by a number of both hepatic and extra-hepatic biological factors. Growing evidence indicates that adipokines, a group of cytokines produced by adipose tissue, impart dynamic functions in liver and are involved in modulation of hepatic fibrosis. In particular, two key adipokines, adiponectin and leptin, directly regulate many biological responses closely associated with development and progression of hepatic fibrosis. Leptin acts as a pro-fibrogenic cytokine, while adiponectin possesses anti-fibrogenic and anti-inflammatory properties. Adiponectin, acting via its cognate receptors, adiponectin receptors 1 and 2, potently suppresses fibrosis and inflammation in liver via multiple mechanisms. This review summarizes recent findings concerning the role of adiponectin in fibrogenic process in liver and addresses the underlying molecular mechanisms in modulation of fibrosis.