Adiponectin: action, regulation and association to insulin sensitivity

Large-for-Gestational-Age, Leptin, and Adiponectin in Infancy

CONTEXT

Fetal overgrowth "programs" an elevated risk of obesity and type 2 diabetes in adulthood. Plausibly, adipokines may be involved in programming metabolic health.

OBJECTIVE

This work aimed to evaluate whether large-for-gestational-age (LGA), an indicator of fetal overgrowth, is associated with altered circulating leptin and adiponectin levels in infancy, and assess the determinants.

METHODS

In the Canadian 3D birth cohort, we studied 70 LGA (birth weight > 90th percentile) and 140 optimal-for-gestational-age (OGA, 25th-75th percentiles) infants matched by maternal ethnicity, smoking, and gestational age at delivery. The primary outcomes were fasting leptin, and total and high-molecular-weight (HMW) adiponectin concentrations at age 2 years.

RESULTS

LGA infants had higher body mass index (BMI) than OGA infants. However, there were no significant differences in leptin, and total and HMW adiponectin concentrations. Leptin concentrations were positively associated with female sex, weight (z score) gain 0 to 24 months, current BMI, and the sum of triceps and subscapular skinfold thickness, and negatively associated with maternal age and White ethnicity. Female sex was associated with lower total and HMW adiponectin concentrations. Weight (z score) gain 0 to 24 months and current BMI were positively correlated with total and HMW adiponectin concentrations in LGA infants only.

CONCLUSION

This study is the first to demonstrate that LGA does not matter for circulating leptin and adiponectin concentrations in infancy, and there may be LGA-specific positive associations between weight gain or current BMI and adiponectin concentrations in infancy, suggesting dysfunction in establishing the adiposity-adiponectin negative feedback loop in LGA individuals.

Emerging Roles of Adipose Tissue in the Pathogenesis of Psoriasis and Atopic Dermatitis in Obesity

Obesity is a growing epidemic worldwide, and it is also considered a major environmental factor contributing to the pathogenesis of inflammatory skin diseases, including psoriasis (PSO) and atopic dermatitis (AD). Moreover, obesity worsens the course and impairs the treatment response of these inflammatory skin diseases. Emerging evidence highlights that hypertrophied adipocytes and infiltrated immune cells secrete a variety of molecules, including fatty acids and adipokines, such as leptin, adiponectin, and a panel of cytokines/chemokines that modulate our immune system. In this review, we describe how adipose hypertrophy leads to a chronic low-grade inflammatory state in obesity and how obesity-related inflammatory factors are involved in the pathogenesis of PSO and/or AD. Finally, we discuss the potential role of antimicrobial peptides, mechanical stress and impairment of epidermal barrier function mediated by fast expansion, and dermal fat in modulating skin inflammation. Together, this review summarizes the current literature on how obesity is associated with the pathogenesis of PSO and AD, highlighting the potentially important but overlooked immunomodulatory role of adipose tissue in the skin.

Fat Cell Size: Measurement Methods, Pathophysiological Origins, and Relationships With Metabolic Dysregulations

The obesity pandemic increasingly causes morbidity and mortality from type 2 diabetes, cardiovascular diseases and many other chronic diseases. Fat cell size (FCS) predicts numerous obesity-related complications such as lipid dysmetabolism, ectopic fat accumulation, insulin resistance, and cardiovascular disorders. Nevertheless, the scarcity of systematic literature reviews on this subject is compounded by the use of different methods by which FCS measurements are determined and reported. In this paper, we provide a systematic review of the current literature on the relationship between adipocyte hypertrophy and obesity-related glucose and lipid dysmetabolism, ectopic fat accumulation, and cardiovascular disorders. We also review the numerous mechanistic origins of adipocyte hypertrophy and its relationship with metabolic dysregulation, including changes in adipogenesis, cell senescence, collagen deposition, systemic inflammation, adipokine secretion, and energy balance. To quantify the effect of different FCS measurement methods, we performed statistical analyses across published data while controlling for body mass index, age, and sex.

The Association of Vitamin K2 Level with the Glycaemic Status in Type 2 Diabetic Patients: A Case-Control Study

OBJECTIVES

The target of this work was to investigate vitamin K2 level link to glycaemic status in type 2 diabetes mellitus (T2DM) patients.

METHODOLOGY

Sixty T2DM patients were divided into 30 uncontrolled T2DM (group I), 30 controlled T2DM (group II) patients and 30 non-diabetic subjects as the control group. Vitamin K2 level, fasting insulin, homeostasis model assessment insulin resistance (HOMA-IR), fasting blood glucose (FBG), 2-h postprandial blood glucose (PPG), glycosylated haemoglobin (HbA1c) and fasting lipids were documented. Waist circumference (WC) was measured and body mass index (BMI) was calculated.

RESULTS

A highly significant difference between groups was observed in vitamin K2 level (P < 0.001) being 1.61 ± 0.56 ng/ml, 2.04 ± 0.59 ng/ml and 2.96 ± 0.82 ng/ml for groups I, II and III, respectively. Among diabetics, a negative correlation was reported between serum vitamin K2 and FBG (r -0.428), 2-h PPBG (r -0.319), HbA1c (r -0.268), fasting insulin (r -0.49), HOMA-IR (r -0.5), total cholesterol (T-cholesterol) (r -0.335) and LDL-C (r -0.296) with P < 0.05. The receiver operating characteristic (ROC) curve emphasized the utility of the discriminated potentiality of serum vitamin K2 as a biomarker for uncontrolled hyperglycaemia in T2DM. The multivariate linear regression has shown that FBG is the only significant independent predictor of serum levels of vitamin K2.

CONCLUSIONS

In T2DM patients, serum vitamin K2 level was significantly lower, especially with uncontrolled hyperglycaemia. This suggests that vitamin K2 level has an association with the glycaemic status in T2DM.

Abdominal Adipose Tissue Associates With Adiponectin and TNFα in Middle-Aged Healthy Men

INTRODUCTION

Adipokines are highly active biopeptides involved in glucose metabolism, insulin regulation and the development and progression of obesity and its associated diseases. It includes, among others, adiponectin, visfatin and tumor necrosis factor alpha (TNFα). The sources of adipokines and their associations with glucometabolic variables are not completely understood.

AIM

In this cross-sectional study, we aimed to investigate whether gene expression levels in subcutaneous adipose tissue (SAT) of selected adipokines and their corresponding circulating levels associate with the amount of AT in superficial (sSAT), deep (dSAT) and visceral AT (VAT), assessed by computed tomography (CT). Any association with glucometabolic variables were also explored.

METHODS

In 103 healthy Caucasian men, aged 39.5 years, fasting venous blood and SAT samples from the gluteal region were collected. Ninety-four of the participants underwent CT assessment of the abdominal AT, which was divided into VAT, sSAT and dSAT. Circulating levels of adipokines were measured by ELISA and AT gene-expression by PCR. Insulin sensitivity was determined by glucose clamp, assessing glucose disposal rate (GDR).

RESULTS

Circulating adiponectin and TNFα gene expression correlated inversely and positively to the amount of AT in all three compartments (r=-0.266 to -0.276, p<0.05 for all) and (r=0.323 - 0.368, p<0.05 for all), respectively, with strongest correlations to the amount in sSAT and dSAT. When dividing AT compartments into quartiles, a tendency was observed towards lower circulating adiponectin and higher TNFα gene expression levels, respectively, with increasing amount of sSAT and dSAT. Circulating adiponectin correlated inversely to insulin, C-peptide and waist circumference (r=-456 to -0.373, p<0.001) and positively to GDR (r=0.356, p<0.001). AT-expressed visfatin correlated inversely to insulin and C-peptide (r=-0.370 and r=-0.404, p<0.001).

CONCLUSION

Increased amount of AT is associated with lower levels of adiponectin and increased levels of TNFα AT expression.

Which BMI for Diabetes Patients is Better? From the View of the Adipose Tissue Macrophage-Derived Exosome

PURPOSE

Diabetes, as a group of metabolic diseases, can elevate blood glucose, thus leading to the development of life-threatening complications. It is difficult to define the outcome for diabetics with different BMI. This review will illustrate the adipose tissue macrophage-derived exosome in the diabetics with different BMI.

PATIENTS AND METHODS

Insulin resistance in peripheral tissues can cause diabetes. The peripheral tissues include liver, muscle, or the adipose depots. Communication between these organs is fatal to the maintenance of glucose homeostasis. This review will illustrate this communication. Obesity is closely linked with diabetes. There are different changes in fat distribution in diabetic patients. Adipose tissue macrophages can secrete various hormones, including adiponectin, leptin, resistin and other classical cytokines, such as TNF-α and IL-6. Studies illustrated that exosomes from the adipose tissue, can modulate inter-organ cross-talk by regulating gene expression in other tissues.

RESULTS

Adipose tissue macrophages exosomes links thin and fat individuals in the development of diabetes.

CONCLUSION

The molecular pathways initiated by exosomes such as miRNA in the situations of metabolic stress could help us gain a deeper knowledge of the pathophysiology of diabetes.

Blood levels of adiponectin and IL-1Ra distinguish type 3c from type 2 diabetes: Implications for earlier pancreatic cancer detection in new-onset diabetes

BACKGROUND

Screening for pancreatic ductal adenocarcinoma (PDAC) in populations at high risk is recommended. Individuals with new-onset type 2 diabetes mellitus (NOD) are the largest high-risk group for PDAC. To facilitate screening, we sought biomarkers capable of stratifying NOD subjects into those with type 2 diabetes mellitus (T2DM) and those with the less prevalent PDAC-related diabetes (PDAC-DM), a form of type 3c DM commonly misdiagnosed as T2DM.

METHODS

Using mass spectrometry- and immunoassay-based methodologies in a multi-stage analysis of independent sample sets (n=443 samples), blood levels of 264 proteins were considered using Ingenuity Pathway Analysis, literature review and targeted training and validation.

FINDINGS

Of 30 candidate biomarkers evaluated in up to four independent patient sets, 12 showed statistically significant differences in levels between PDAC-DM and T2DM. The combination of adiponectin and interleukin-1 receptor antagonist (IL-1Ra) showed strong diagnostic potential, (AUC of 0.91; 95% CI: 0.84-0.99) for the distinction of T3cDM from T2DM.

INTERPRETATION

Adiponectin and IL-1Ra warrant further consideration for use in screening for PDAC in individuals newly-diagnosed with T2DM.

FUNDING

North West Cancer Research, UK, Cancer Research UK, Pancreatic Cancer Action, UK.

Epigenetics in the Uterine Environment: How Maternal Diet and ART May Influence the Epigenome in the Offspring with Long-Term Health Consequences

The societal burden of non-communicable disease is closely linked with environmental exposures and lifestyle behaviours, including the adherence to a poor maternal diet from the earliest preimplantation period of the life course onwards. Epigenetic variations caused by a compromised maternal nutritional status can affect embryonic development. This review summarises the main epigenetic modifications in mammals, especially DNA methylation, histone modifications, and ncRNA. These epigenetic changes can compromise the health of the offspring later in life. We discuss different types of nutritional stressors in human and animal models, such as maternal undernutrition, seasonal diets, low-protein diet, high-fat diet, and synthetic folic acid supplement use, and how these nutritional exposures epigenetically affect target genes and their outcomes. In addition, we review the concept of thrifty genes during the preimplantation period, and some examples that relate to epigenetic change and diet. Finally, we discuss different examples of maternal diets, their effect on outcomes, and their relationship with assisted reproductive technology (ART), including their implications on epigenetic modifications.

Galangin 3-benzyl-5-methylether derivatives function as an adiponectin synthesis-promoting peroxisome proliferator-activated receptor γ partial agonist

The upregulation of adiponectin production has been suggested as a novel strategy for the treatment of metabolic diseases. Galangin, a natural flavonoid, exhibited adiponectin synthesis-promoting activity during adipogenesis in human bone marrow mesenchymal stem cells. In target identification, galangin bound both peroxisome proliferator-activated receptor (PPAR) γ and estrogen receptor (ER) β. Novel galangin derivatives were synthesized to improve adiponectin synthesis-promoting compounds by increasing the PPARγ activity of galangin and reducing its ERβ activity, because PPARγ functions can be inhibited by ERβ. Three galangin 3-benzyl-5-methylether derivatives significantly promoted adiponectin production by 2.88-, 4.47-, and 2.76-fold, respectively, compared to the effect of galangin. The most potent compound, galangin 3-benzyl-5,7-dimethylether, selectively bound to PPARγ (Ki, 1.7 μM), whereas it did not bind to ERβ. Galangin 3-benzyl-5,7-dimethylether was identified as a PPARγ partial agonist in docking and pharmacological competition studies, suggesting that it may have diverse therapeutic potential in a variety of metabolic diseases.

Adipocyte-specific tribbles pseudokinase 1 regulates plasma adiponectin and plasma lipids in mice

OBJECTIVE

Multiple genome-wide association studies (GWAS) have identified SNPs in the 8q24 locus near TRIB1 that are significantly associated with plasma lipids and other markers of cardiometabolic health, and prior studies have revealed the roles of hepatic and myeloid Trib1 in plasma lipid regulation and atherosclerosis. The same 8q24 SNPs are additionally associated with plasma adiponectin levels in humans, implicating TRIB1 in adipocyte biology. Here, we hypothesize that TRIB1 in adipose tissue regulates plasma adiponectin, lipids, and metabolic health.

METHODS

We investigate the metabolic phenotype of adipocyte-specific Trib1 knockout mice (Trib1_ASKO) fed on chow and high-fat diet (HFD). Through secretomics of adipose tissue explants and RNA-seq of adipocytes and livers from these mice, we further investigate the mechanism of TRIB1 in adipose tissue.

RESULTS

Trib1_ASKO mice have an improved metabolic phenotype with increased plasma adiponectin levels, improved glucose tolerance, and decreased plasma lipids. Trib1_ASKO adipocytes have increased adiponectin production and secretion independent of the known TRIB1 function of regulating proteasomal degradation. RNA-seq analysis of adipocytes and livers from Trib1_ASKO mice indicates that alterations in adipocyte function underlie the observed plasma lipid changes. Adipose tissue explant secretomics further reveals that Trib1_ASKO adipose tissue has decreased ANGPTL4 production, and we demonstrate an accompanying increase in the lipoprotein lipase (LPL) activity that likely underlies the triglyceride phenotype.

CONCLUSIONS

This study shows that adipocyte Trib1 regulates multiple aspects of metabolic health, confirming previously observed genetic associations in humans and shedding light on the further mechanisms by which TRIB1 regulates plasma lipids and metabolic health.

Environmental Enrichment Mitigates Age-Related Metabolic Decline and Lewis Lung Carcinoma Growth in Aged Female Mice

Aging is a complex physiological process that leads to the progressive decline of metabolic and immune function, among other biological mechanisms. As global life expectancy increases, it is important to understand determinants of healthy aging-including environmental and genetic factors-and thus slow the onset or progression of age-related disease. Environmental enrichment (EE) is a housing environment wherein laboratory animals engage with complex physical and social stimulation. EE is a prime model to understand environmental influences on aging dynamics, as it confers an antiobesity and anticancer phenotype that has been implicated in healthy aging and health span extension. Although EE is frequently used to study malignancies in young mice, fewer studies characterize EE-cancer outcomes in older mice. Here, we used young (3-month-old) and aged (14-month-old) female C57BL/6 mice to determine whether EE would be able to mitigate age-related deficiencies in metabolic function and thus alter Lewis lung carcinoma (LLC) growth. Overall, EE improved metabolic function, resulting in reduced fat mass, increased lean mass, and improved glycemic processing; many of these effects were stronger in the aged cohort than in the young cohort, indicating an age-driven effect on metabolic responses. In the aged-EE cohort, subcutaneously implanted LLC tumor growth was inhibited and tumors exhibited alterations in various markers of apoptosis, proliferation, angiogenesis, inflammation, and malignancy. These results validate EE as an anticancer model in aged mice and underscore the importance of understanding environmental influences on cancer malignancy in aged populations. PREVENTION RELEVANCE: Environmental enrichment (EE) serves as a model of complex physical and social stimulation. This study validates EE as an anticancer intervention paradigm in aged mice and underscores the importance of understanding environmental influences on cancer malignancy in aged populations.

The correlation between carbamazepine and valproic acid monotherapy with serum adiponectin and carnitine

Antiepileptic drugs may cause systemic and metabolic side effects. The aim of our study was to investigate the effects of valproic acid and carbamazepine monotherapy used in the treatment of epilepsy patients on serum adiponectin and carnitine levels. The study included 60 patients, of which 30 patients receiving valproic acid monotherapy and 30 patients receiving carbamazepine monotherapy, who were followed up by the epilepsy outpatient clinic with the diagnosis of idiopathic epilepsy, and 30 healthy volunteers. Patients, who used drugs for at least 6 months, were selected. Venous blood samples were collected from the patients and healthy volunteers after their consent was obtained. Serum carnitine and adiponectin levels in the collected samples were measured using the ELISA method. Serum carnitine levels were 5166.55 ng/ml (± 1954.92) in patients receiving carbamazepine, 4224.56 ng/ml (± 2055.54) in patients using valproic acid, and 5802.64 ng/ml (± 3422.57) in the control group. Serum adiponectin levels were 13,606.51 ng/ml (± 5915.92) in patients using carbamazepine, 11,986.58 ng/ml (± 5367.82) in patients receiving valproic acid, and 14,033.43 ng/ml (± 5646.34) in the control group. In both groups, both serum carnitine and serum adiponectin levels were lower than the control group. There was a negative but insignificant correlation between the duration and dose of carbamazepine and valproic acid drug use and serum adiponectin and carnitine levels. There is a need for more extensive studies with larger sample size to investigate the effect of antiepileptic drugs used on serum adiponectin and carnitine levels.

WSF-CT-11, a Sesquiterpene Derivative, Activates AMP-Activated Protein Kinase with Anti-diabetic Effects in 3T3-L1 Adipocytes

BACKGROUND

AMP-activated protein kinase (AMPK) is a therapeutic target against type II diabetes (T2D). Synthetic sesquiterpene derivatives were investigated to identify novel AMPK activators as anti-diabetic drugs because the leading drugs like metformin and thiazolidinediones (TZDs) activate AMPK by inhibiting the synthesis of adenosine 5'-triphosphate and thus are associated with some side effects.

RESULTS

We identified WSF-CT-11 as an AMPK activator in HEK293T cells and found that WSF-CT-11 activates AMPK by the activation of transient receptor potential vanilloid type 1 (TRPV1), a Ca²⁺-permeable cation channel. The increased Ca²⁺ influx then activates phosphoinositide 3-kinase (PI3K), protein kinase B (PKB/Akt), and Ca²⁺/calmodulin-dependent protein kinase II (CaMKII), which in turn phosphorylates TRPV1 and facilitates the formation of a TRPV1/Akt/CaMKII/AMPK complex. This complex might be important for the regulation of AMPK activity. In 3T3-L1 adipocytes, WSF-CT-11-induced AMPK activation has three anti-diabetic effects. It promotes the assembly of high-molecular-weight adiponectin, which has stronger insulin-sensitizing activity than other multimers. It improves translocation of the glucose transporter type 4, increases glucose uptake, and induces the inhibitory phosphorylation of peroxisome proliferator-activated receptor γ and thus suppresses adipogenesis.

CONCLUSION

WSF-CT-11 is a novel AMPK activator and potential drug against T2D without the side effects of metformin and TZDs.

MLR-1023 Treatment in Mice and Humans Induces a Thermogenic Program, and Menthol Potentiates the Effect

A glucose-lowering medication that acts by a different mechanism than metformin, or other approved diabetes medications, can supplement monotherapies when patients fail to meet blood glucose goals. We examined the actions underlying the effects of an insulin sensitizer, tolimidone (MLR-1023) and investigated its effects on body weight. Diet-induced obesity (CD1/ICR) and type 2 diabetes (db/db) mouse models were used to study the effect of MLR-1023 on metabolic outcomes and to explore its synergy with menthol. We also examined the efficacy of MLR-1023 alone in a clinical trial (NCT02317796), as well as in combination with menthol in human adipocytes. MLR-1023 produced weight loss in humans in four weeks, and in mice fed a high-fat diet it reduced weight gain and fat mass without affecting food intake. In human adipocytes from obese donors, the upregulation of Uncoupling Protein 1, Glucose (UCP)1, adiponectin, Glucose Transporter Type 4 (GLUT4), Adipose Triglyceride Lipase (ATGL), Carnitine palmitoyltransferase 1 beta (CPT1β), and Transient Receptor Potential Melastin (TRPM8) mRNA expression suggested the induction of thermogenesis. The TRPM8 agonist, menthol, potentiated the effect of MLR-1023 on the upregulation of genes for energy expenditure and insulin sensitivity in human adipocytes, and reduced fasting blood glucose in mice. The amplification of the thermogenic program by MLR-1023 and menthol in the absence of adrenergic activation will likely be well-tolerated, and bears investigation in a clinical trial.

Chitosan for biomedical applications, promising antidiabetic drug delivery system, and new diabetes mellitus treatment based on stem cell

Since chitosan's excellent pharmacokinetic and chemical properties, it is an attractive and promising carbohydrate biopolymer in biomedical applications. Chitosan's beneficial function in the defense and propagation of pancreatic β cells, reducing hyperglycemia, and avoiding diabetes mellitus associated with impaired lipid metabolism has been demonstrated in several studies. Additionally, chitosan has also been used in various nanocarriers to deliver various antidiabetic drugs to reduce glucose levels. Herein, the first to provide the currently available potential benefits of chitosan in diabetes mellitus treatment focuses on chitosan-based nanocarriers for oral administration of various antidiabetic drugs nasal and subcutaneous passages. Moreover, chitosan is used to activate and deliver stem cells and differentiate them into cells similar to pancreatic beta cells as a new type of treatment for type one diabetes mellitus. The results of this review will be helpful in the development of promising treatments and better control of diabetes mellitus.

Circulating tryptophan metabolites and risk of colon cancer: Results from case-control and prospective cohort studies

Dysregulation of tryptophan metabolism has been linked to colorectal tumorigenesis; however, epidemiological studies investigating tryptophan metabolites in relation to colorectal cancer risk are limited. We studied associations of plasma tryptophan, serotonin and kynurenine with colon cancer risk in two studies with cancer patients and controls, and in one prospective cohort: ColoCare Study (110 patients/153 controls), the Colorectal Cancer Study of Austria (CORSA; 46 patients/390 controls) and the European Prospective Investigation into Cancer and Nutrition (EPIC; 456 matched case-control pairs). Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for colon cancer risk. Tryptophan was inversely associated with colon cancer risk in ColoCare (OR per 1-SD = 0.44; 95% CI, 0.31-0.64) and EPIC (OR per 1-SD = 0.86; 95% CI, 0.74-0.99). Comparing detectable vs nondetectable levels, serotonin was positively associated with colon cancer in CORSA (OR = 6.39; 95% CI, 3.61-11.3) and EPIC (OR = 2.03; 95% CI, 1.20-3.40). Kynurenine was inversely associated with colon cancer in ColoCare (OR per 1-SD = 0.74; 95% CI, 0.55-0.98), positively associated in CORSA (OR per 1-SD = 1.79; 95% CI, 1.27-2.52), while no association was observed in EPIC. The kynurenine-to-tryptophan ratio was positively associated with colon cancer in ColoCare (OR per 1-SD = 1.38; 95% CI, 1.03-1.84) and CORSA (OR per 1-SD = 1.44; 95% CI, 1.06-1.96), but not in EPIC. These results suggest that higher plasma tryptophan may be associated with lower colon cancer risk, while increased serotonin may be associated with a higher risk of colon cancer. The kynurenine-to-tryptophan ratio may also reflect altered tryptophan catabolism during colon cancer development.

Long-term obesity is associated with depression and neuroinflammation

OBJECTIVE

Obesity is characterized by a state of chronic, low-intensity systemic inflammation frequently associated with insulin resistance and dyslipidemia.

METHODS

Given that chronic inflammation has been implicated in the pathogenesis of mood disorders, we investigated if chronic obesity that was initiated early in life - lasting through adulthood - could be more harmful to memory impairment and mood fluctuations such as depression.

RESULTS

Here we show that pre-pubertal male rats (30 days old) treated with a high-fat diet (40%) for 8-months gained ~50% more weight when compared to controls, exhibited depression and anxiety-like behaviors but no memory impairment. The prefrontal cortex of the obese rats exhibited an increase in the expression of genes related to inflammatory response, such as NFKb, MMP9, CCl2, PPARb, and PPARg. There were no alterations in genes known to be related to depression.

CONCLUSION

Long-lasting obesity with onset in prepuberal age led to depression and neuroinflammation but not to memory impairment.

Resistin forms a network with inflammatory cytokines and is associated with prognosis in major burns

BACKGROUND

In current intensive care treatment, some patients with severe burns cannot be saved due to progressive organ failure. Further investigation of the pathogenesis of severe burns is needed to improve the mortality rate. In burns, inflammatory cytokines form a network that leads to an inflammatory response. Adipocytes secrete physiologically active substances (adipokines). The roles of adipokines have not been completely clarified in burn patients. This study aimed to determine the relation between serial changes of adipokines and clinical course in severely burned patients.

METHODS

This was a single-center, retrospective, observational study. Patients' blood samples were collected on the day of injury and around 1 week later. Adipokines (adiponectin, angiotensinogen, chemerin, CXCL-12/SDF-1, leptin, resistin, vaspin, visfatin), various inflammatory cytokines, syndecan-1 and C1 esterase inhibitor were measured.

RESULTS

Thirty-eight patients were included. Resistin levels were significantly higher in the non-survivors versus survivors on Day 1 after burn injury. Hierarchical clustering analysis showed common clusters on Day 1 and at 1 Week after burn injury (resistin, IL-6, IL-8, IL10 and MCP-1). The correlation coefficient of resistin to SOFA score at 1 Week was significant. Logistic regression analysis showed a significant relation of resistin levels on Day 1 with prognosis; the area under the ROC curve for resistin was 0.801.

CONCLUSIONS

In the acute phase of burns, resistin was associated with other pro-inflammatory cytokines and was related to the severity and prognosis of major burns.

Chamomile as a potential remedy for obesity and metabolic syndrome

Obesity is an increasing health concern related to many metabolic disorders, including metabolic syndrome, diabetes type 2 and cardiovascular diseases. Many studies suggest that herbal products can be useful dietary supplements for weight management due to the presence of numerous biologically active compounds, including antioxidant polyphenols that can counteract obesity-related oxidative stress. In this review we focus on Matricaria chamomilla, commonly known as chamomile, and one of the most popular medicinal plants in the world. Thanks to a high content of phenolic compounds and essential oils, preparations from chamomile flowers demonstrate a number of pharmacological effects, including antioxidant, anti-inflammatory, antimicrobial and sedative actions as well as improving gastrointestinal function. Several recent studies have shown certain positive effects of chamomile preparations in the prevention of obesity and complications of diabetes. These effects were associated with modulation of signaling pathways involving the AMP-activated protein kinase, NF-κB, Nrf2 and PPARγ transcription factors. However, the potential of chamomile in the management of obesity seems to be underestimated. This review summarizes current data on the use of chamomile and its individual components (apigenin, luteolin, essential oils) to treat obesity and related metabolic disorders in cell and animal models and in human studies. Special attention is paid to molecular mechanisms that can be involved in the anti-obesity effects of chamomile preparations. Limitation of chamomile usage is also analyzed.

Obesity-An Update on the Basic Pathophysiology and Review of Recent Therapeutic Advances

Obesity represents a major public health problem with a prevalence increasing at an alarming rate worldwide. Continuous intensive efforts to elucidate the complex pathophysiology and improve clinical management have led to a better understanding of biomolecules like gut hormones, antagonists of orexigenic signals, stimulants of fat utilization, and/or inhibitors of fat absorption. In this article, we will review the pathophysiology and pharmacotherapy of obesity including intersection points to the new generation of antidiabetic drugs. We provide insight into the effectiveness of currently approved anti-obesity drugs and other therapeutic avenues that can be explored.

Adipokines in metabolic and reproductive functions in birds: An overview of current knowns and unknowns

Adipose tissue is now recognized as an active endocrine organ, which synthesizes and secretes numerous peptides factors called adipokines. In mammals, they exert pleiotropic effects affecting energy metabolism but also fertility. In mammals, secretion of adipokines is altered in adipose tissue dysfunctions and may participate to obesity-associated disorders. Thus, adipokines are promising candidates both for novel pharmacological treatment strategies and as diagnostic tools. As compared to mammals, birds exhibit several unique physiological features, which make them an interesting model for comparative studies on endocrine control of metabolism and adiposity and reproductive functions. Some adipokines such as leptin and visfatin may have different roles in avian species as compared to mammals. In addition, some of them found in mammals such as CCL2 (chemokine ligand 2), resistin, omentin and FGF21 (Fibroblast Growth factor 21) have not yet been mapped to the chicken genome model and among its annotated gene models. This brief review aims to summarize data (structure, metabolic and reproductive roles and molecular mechanisms involved) related to main avian adipokines (leptin, adiponectin, visfatin, and chemerin) and we will briefly discuss the adipokines that are still lacking in avian species.

Human Milk Metabolic Hormones: Analytical Methods and Current Understanding

Human milk (HM) contains a wide array of peptide hormones including leptin and adiponectin, which are involved in the regulation of infant growth and development. These essential hormones might play an important role in the regulation of metabolic reprogramming of the new-born infant. However, HM hormone studies are sparse and heterogeneous in regard to the study design, sample collection, preparation and analysis methods. This review discussed the limitations of HM hormone analysis highlighting the gaps in pre-analytical and analytical stages. The methods used to quantify HM metabolic hormones (leptin, adiponectin, ghrelin, insulin, obestatin, resistin and apelin) can be classified as immunoassay, immunosensor and chromatography. Immunoassay methods (ELISA and RIA) have been predominantly used in the measurement of these HM hormones. The relative validity parameters of HM hormones analysis are often overlooked in publications, despite the complexity and differences of HM matrix when compared to that of plasma and urine. Therefore, appropriate reports of validation parameters of methodology and instrumentation are crucial for accurate measurements and therefore better understanding of the HM metabolic hormones and their influences on infant outcomes.

A Review of Current Trends with Type 2 Diabetes Epidemiology, Aetiology, Pathogenesis, Treatments and Future Perspectives

Type 2 diabetes (T2D), which has currently become a global pandemic, is a metabolic disease largely characterised by impaired insulin secretion and action. Significant progress has been made in understanding T2D aetiology and pathogenesis, which is discussed in this review. Extrapancreatic pathology is also summarised, which demonstrates the highly multifactorial nature of T2D. Glucagon-like peptide (GLP)-1 is an incretin hormone responsible for augmenting insulin secretion from pancreatic beta-cells during the postprandial period. Given that native GLP-1 has a very short half-life, GLP-1 mimetics with a much longer half-life have been developed, which are currently an effective treatment option for T2D by enhancing insulin secretion in patients. Interestingly, there is continual emerging evidence that these therapies alleviate some of the post-diagnosis complications of T2D. Additionally, these therapies have been shown to induce weight loss in patients, suggesting they could be an alternative to bariatric surgery, a procedure associated with numerous complications. Current GLP-1-based therapies all act as orthosteric agonists for the GLP-1 receptor (GLP-1R). Interestingly, it has emerged that GLP-1R also has allosteric binding sites and agonists have been developed for these sites to test their therapeutic potential. Recent studies have also demonstrated the potential of bi- and tri-agonists, which target multiple hormonal receptors including GLP-1R, to more effectively treat T2D. Improved understanding of T2D aetiology/pathogenesis, coupled with the further elucidation of both GLP-1 activity/targets and GLP-1R mechanisms of activation via different agonists, will likely provide better insight into the therapeutic potential of GLP-1-based therapies to treat T2D.

Adiponectin in psoriasis and its comorbidities: a review

Psoriasis is a chronic, immune-mediated inflammatory skin disease characterized by abnormal T cell activation and excessive proliferation of keratinocytes. In addition to skin manifestations, psoriasis has been associated with multiple metabolic comorbidities, such as obesity, insulin resistance, and diabetes. An increasing amount of evidence has highlighted the core role of adipokines in adipose tissue and the immune system. This review focus on the role of adiponectin in the pathophysiology of psoriasis and its comorbidities, highlighting the future research avenues.

Lipocalin-type Prostaglandin D2 Synthase appears to function as a Novel Adipokine Preventing Adipose Dysfunction in response to a High Fat Diet

Adipose dysfunction is the primary defect in obesity that contributes to the development of dyslipidemia, insulin resistance, cardiovascular diseases, type 2 diabetes, non-alcoholic fatty liver disease (NAFLD) and some cancers. Previously, we demonstrated the development of NAFLD in lipocalin-type prostaglandin D₂ synthase (L-PGDS) knockout mice regardless of diet. In the present study, we examined the role of L-PGDS in adipose in response to a high fat diet. We observed decreased expression of L-PGDS in adipose tissue and concomitant lower plasma levels in a dietary model of obesity as well as in insulin resistant 3T3-L1 adipocytes. We show reduced adiponectin expression and phosphorylation of AMPK in white adipose tissue of L-PGDS KO mice after 14 weeks on a high fat diet as compared to control C57BL/6 mice. We also observe an increased fat content in L-PGDS KO mice as demonstrated by adipocyte hypertrophy and increased expression of lipogenenic genes. We confirmed our in vivo findings in in vitro 3T3-L1 adipocytes, using an enzymatic inhibitor of L-PGDS (AT56). Rosiglitazone treatment drastically increased L-PGDS expression in insulin resistant 3T3-L1 adipocytes and increased adiponectin expression and AMPK phosphorylation in AT56 treated 3T3-L1 adipocytes. We conclude that the absence of L-PGDS has a deleterious effect on adipose tissue functioning, which further reduces insulin sensitivity in adipose tissue. Consequently, we propose L-PGDS appears to function as a potential member of the adipokine secretome involved in the regulation of the obesity-associated metabolic syndrome.

Effects of Obesity on Adiponectin System Skin Expression in Dogs: A Comparative Study

Simple Summary

Adipokines are biologically active molecules with hormonal action, produced mainly by white adipose tissue and related to the individual’s nutritional status. Adiponectin with its receptors (ADIPOR1, ADIPOR2) intervenes in the control of energy metabolism, as well as in the regulation of peripheral tissue functions. Adiponectin has a primary role in the skin in both physiological and pathological conditions, in addition, this molecule is greatly affected by nutritional status, and its serum level is lowered in the obese. In this work, the adiponectin system was evaluated in the skin of obese dogs along with adiponectin serum levels. Results were compared to normal weight dogs to evidence modifications in the obesity condition. Obesity is a widespread phenomenon in dogs, with a growing trend, as well, in humans; this condition may interfere with the local functionality of tissues, including the skin. The evaluation performed evidenced that adiponectin and ADIPOR2 skin expression is negatively correlated with the serum adiponectin level and accordingly with obesity. These findings evidence that the adiponectin system changes in the skin of obese dogs; this study also explores the role of adipokines in skin biology.

Abstract

Obesity is an important health issue in dogs since it influences a plethora of associated pathologies, including dermatological disorders. Considering the scarcity of information in pets, this work aimed to evaluate the localization and expression of adiponectin (ADIPOQ) and its two receptors (ADIPOR1 and ADIPOR2) in the skin of 10 obese dogs, compared with serum ADIPOQ level. Through immunohistochemistry, ADIPOQ and ADIPOR2 were observed in the adipose tissue, sweat and sebaceous glands, endothelium, and some connective cells. Both receptors were observed in the epidermis and the hair follicles, other than in the sweat and sebaceous glands. Real-time PCR evidenced that the ADIPOQ and ADIPOR2 transcripts were expressed 5.4-fold (p < 0.01) and 2.3-fold less (p < 0.01), respectively, in obese than in normal weight dogs, while ADIPOR1 expression did not change. Obese dogs showed lower serum ADIPOQ levels than the normal weight group. Accordingly, ADIPOQ and ADIPOR2 expression in the skin appear negatively correlated with obesity in the same way as the serum ADIPOQ level. These findings evidence that ADIPOQ system changes in the skin of obese dogs and suggest that the ADIPOQ effect on the skin is at least in part regulated by the reduced expression of ADIPOR2.

Relationship between Adipose Tissue Derived Hormones and Cardiometabolic Risk according to Obesity Status

Adiponectin, and leptin are adipose tissue derived hormones affecting metabolic status. This study aimed to investigate the relationship between circulating adiponectin and leptin levels, and cardiometabolic parameters by obesity status among healthy women without metabolic disease. Finally 141 participants were included in the analyses and categorized into three groups by their body mass index (kg/m²) (normal weight: 18.5 ≤ body mass index [BMI] < 23.0, n=65; overweight: 23.0 ≤ BMI < 25.0, n=26; obesity: 25.0 ≤ BMI, n=50). Overweight and obesity groups were older, and had significantly higher levels of adiposity, blood pressure, fasting glucose, triglyceride, and high sensitivity C-reactive protein (hs-CRP), and lower levels of high density lipoprotein (HDL)-cholesterol than normal weight group. Circulating leptin levels, and leptin to adiponectin ratio were highest in obesity group, but circulating adiponectin levels were not statistically different among the three groups. Circulating leptin levels were negatively correlated with adiponectin levels, and leptin to adiponectin ratio. In addition, leptin levels were positively correlated with waist circumference, systolic blood pressure, insulin resistance, and hs-CRP, and negatively with HDL-cholesterol. However, circulating adiponectin levels were negatively correlated only with waist circumference, and hs-CRP. These patterns were retained after adjusted for confounding factors such as age, smoking and drinking habits, menopausal status and total calorie intake. In conclusion, circulating adiponectin and leptin levels according to obesity status were differently observed among healthy women, and circulating leptin levels may be a more sensitive parameter for cardiometabolic risk in healthy women.

Maternal effects in mammals: Broadening our understanding of offspring programming

The perinatal period is a sensitive time in mammalian development that can have long-lasting consequences on offspring phenotype via maternal effects. Maternal effects have been most intensively studied with respect to two major conditions: maternal diet and maternal stress. In this review, we shift the focus by discussing five major additional maternal cues and their influence on offspring phenotype: maternal androgen levels, photoperiod (melatonin), microbiome, immune regulation, and milk composition. We present the key findings for each of these topics in mammals, their mechanisms of action, and how they interact with each other and with the maternal influences of diet and stress. We explore their impacts in the contexts of both predictive adaptive responses and the developmental origins of disease, identify knowledge gaps and research opportunities in the field, and place a particular emphasis on the application and consideration of these effects in non-model species and natural ecological systems.

Hyperbaric oxygen therapy affects insulin sensitivity/resistance by increasing adiponectin, resistin, and plasminogen activator inhibitor-I in rats

Background/aim

Hyperbaric oxygen therapy (HBOT) causes insulin sensitivity, but the reason for this is not known yet. The aim of the present study was to investigate the effect of HBOT on insulin sensitivity via resistin, plasminogen activator inhibitor-I (PAI - I), and adiponectin.

Materials and methods

The study was designed using HBOT and control groups, with eight rats in each group. After 20 days of HBOT under 2.5 atmospheres for 90 min, the fasting insulin (FI), resistin, PAI-I, homeostatic model assessment of insulin resistance scores (HOMA–IR), quantitative insulin sensitivity check index (QUICKI), fasting plasma glucose (FPG), triglyceride, and high-density lipoprotein cholesterol (HDL-C) in the plasma were measured. The resistin, PAI-I, and adiponectin mRNA expression levels were also measured in the adipose tissue.

Results

Compared to the control group, the FI, FPG, and HOMA-IR scores were significantly lower in the HBOT group, whereas the HDL-C and QUICKI scores were found to be higher. In addition, the resistin, adiponectin, and PAI-I mRNA expression levels were also higher in the HBOT group.

Conclusion

The present study demonstrated that the HBOT had regulated the FI, FPG, and HDL-C associated with metabolic syndrome and diabetes mellitus. Moreover, the study showed that HBOT causes insulin sensitivity by raising adiponectin.

Chronic AdipoRon Treatment Mimics the Effects of Physical Exercise on Restoring Hippocampal Neuroplasticity in Diabetic Mice

Administration of exercise mimetic drugs could be a novel therapeutic approach to combat comorbid neurodegeneration and metabolic syndromes. Adiponectin is an adipocyte-secreted hormone. In addition to its antidiabetic effect, adiponectin mediates the antidepressant effect of physical exercise associated with adult hippocampal neurogenesis. The antidiabetic effect of the adiponectin receptor agonist AdipoRon has been demonstrated, but its potential pro-cognitive and neurotrophic effects in the hippocampus under diabetic condition are still unclear. This study reported that chronic AdipoRon treatment for 2 weeks improved hippocampal-dependent spatial recognition memory in streptozotocin-induced diabetic mice. Besides, AdipoRon treatment increased progenitor cell proliferation and neuronal differentiation in the hippocampal dentate gyrus (DG) of diabetic mice. Furthermore, AdipoRon treatment significantly increased dendritic complexity, spine density, and N-methyl-D-aspartate receptor-dependent long-term potentiation (LTP) in the dentate region, and increased BDNF levels in the DG of diabetic mice. AdipoRon treatment activated AMPK/PGC-1α signalling in the DG, whereas increases in cell proliferation and LTP were not observed when PGC-1α signalling was pharmacologically inhibited. In sum, chronic AdipoRon treatment partially mimics the benefits of physical exercise for learning and memory and hippocampal neuroplasticity in the diabetic brain. The results suggested that AdipoRon could be a potential physical exercise mimetic to improve hippocampal plasticity and hence rescue learning and memory impairment typically associated with diabetes.

Implementation of Christian Orthodox fasting improves plasma adiponectin concentrations compared with time-restricted eating in overweight premenopausal women

The exact mechanisms mediating the metabolic effects of Orthodox fasting remain unclear. Plasma adiponectin, biochemical and anthropometrical data were evaluated in 55 Orthodox fasters (OF) and 42 time-restricted eating controls (all women, mean age 47.8 years) at three time points: baseline, end of the dietary intervention (7 weeks) and 5 weeks after participants returned to their typical dietary habits (12 weeks from baseline). In the OF group, there was an increase in adiponectin values at 12 weeks compared with baseline (9815.99 vs 8983.52 mg/ml, p = 0.02) and a reduction in body fat mass between baseline and 12 weeks (35.44 vs 32.17%, p = 0.004) and between 7 and 12 weeks (35.33 vs 32.17%, p = 0.003). In the same group, an inverse correlation between adiponectin and waist circumference values was observed over the entire study period. Our results provide novel evidence that Orthodox fasting has favourable metabolic effects related to improved adiponectin concentrations.

Body Fat Composition Enhances the Predictive Ability of Changes in White Blood Cell Levels Associated with the Risk of Chronic Disease Development

The study aimed to revalidate the influence of WBCs on chronic disease risk factors and to verify which markers are independently involved in WBC level changes in a Korean population. A total of 80 Korean subjects were divided into three groups, according to the WBC count: mild decrease in WBC, normal WBC, and mild increase in WBC. Fasting blood samples for analyzing biochemical parameters and inflammatory markers were obtained from the subjects, and their body fat composition was evaluated by dual energy x-ray absorptiometry and computed tomography. The WBC levels were related to levels of adiponectin, triglyceride, and insulin, which are associated with the risk of chronic diseases. In the mild increase in WBC group, high-sensitivity C-reactive protein (hs-CRP) and TNF-α levels increased, and s.c. fat area at the first lumbar vertebrae and fourth lumbar vertebrae decreased. The WBC count positively correlated with hs-CRP and TNF-α levels and most of the body fat composition data, evaluated by dual energy x-ray absorptiometry and computed tomography. Notably, hs-CRP and TNF-α levels, fat mass, and visceral-to-s.c. fat area ratio at the first lumbar vertebrae were revealed as independent predictors of WBC level change. Finally, the receiver operating characteristic curve analysis showed that the additional use of body fat composition data with the conventional inflammatory markers reliably enhanced the predictive capacity of WBC level changes. Thus, we suggest that by controlling inflammatory markers and body fat composition, WBC levels can be kept within a range that is safe from the risk of chronic diseases.

Contribution of Adipose Tissue to the Chronic Immune Activation and Inflammation Associated With HIV Infection and Its Treatment

White adipose tissue (AT) contributes significantly to inflammation – especially in the context of obesity. Several of AT’s intrinsic features favor its key role in local and systemic inflammation: (i) large distribution throughout the body, (ii) major endocrine activity, and (iii) presence of metabolic and immune cells in close proximity. In obesity, the concomitant pro-inflammatory signals produced by immune cells, adipocytes and adipose stem cells help to drive local inflammation in a vicious circle. Although the secretion of adipokines by AT is a prime contributor to systemic inflammation, the lipotoxicity associated with AT dysfunction might also be involved and could affect distant organs. In HIV-infected patients, the AT is targeted by both HIV infection and antiretroviral therapy (ART). During the primary phase of infection, the virus targets AT directly (by infecting AT CD4 T cells) and indirectly (via viral protein release, inflammatory signals, and gut disruption). The initiation of ART drastically changes the picture: ART reduces viral load, restores (at least partially) the CD4 T cell count, and dampens inflammatory processes on the whole-body level but also within the AT. However, ART induces AT dysfunction and metabolic side effects, which are highly dependent on the individual molecules and the combination used. First generation thymidine reverse transcriptase inhibitors predominantly target mitochondrial DNA and induce oxidative stress and adipocyte death. Protease inhibitors predominantly affect metabolic pathways (affecting adipogenesis and adipocyte homeostasis) resulting in insulin resistance. Recently marketed integrase strand transfer inhibitors induce both adipocyte adipogenesis, hypertrophy and fibrosis. It is challenging to distinguish between the respective effects of viral persistence, persistent immune defects and ART toxicity on the inflammatory profile present in ART-controlled HIV-infected patients. The host metabolic status, the size of the pre-established viral reservoir, the quality of the immune restoration, and the natural ageing with associated comorbidities may mitigate and/or reinforce the contribution of antiretrovirals (ARVs) toxicity to the development of low-grade inflammation in HIV-infected patients. Protecting AT functions appears highly relevant in ART-controlled HIV-infected patients. It requires lifestyle habits improvement in the absence of effective anti-inflammatory treatment. Besides, reducing ART toxicities remains a crucial therapeutic goal.

Effect of liraglutide on microcirculation in rat model with absolute insulin deficiency

INTRODUCTION

The investigations of angiotropic effects of liraglutide are an issue of significant scientific and practical interest. The successful application of liraglutide has been shown in glycemic control in patients with the type 2 diabetes mellitus (DM), but the effect of liraglutide in patients with type 1 DM has not been completely studied yet in clinical practice. Therefore, the present study is aimed to investigate the effect of liraglutide which is agonist of glucagon-like peptide-1 receptors, on microcirculation in white outbred rats with the alloxan-induced diabetes.

MATERIALS AND METHODS

The study was performed with 70 white outbred rats, divided into 4 groups: 1) control group (intact animals (Control)); 2) comparison group (diabetes mellitus (DM)) - animals with the alloxan-induced diabetes; 3) experimental group no. 1 (liraglutide low dose (LLD)) - animals with the alloxan-induced diabetes, which were injected by liraglutide at dosage of 0.2 mg/kg of animal weight per a day; 4) experimental group no. 2 (liraglutide high dose (LHD)) - animals with the alloxan-induced diabetes, which were injected by liraglutide at dosage of 0.4 mg/kg of animal weight per a day. The carbohydrate metabolism disorders, the microcirculation of posterior paw skin, as well as the concentration of catecholamines and markers of endothelial alteration in blood were estimated at the 42nd day of the experiment in the comparison and experimental groups.

RESULTS

It was found that the correction of carbohydrate metabolism by liraglutide is succeeded by the normalization of skin perfusion of posterior paw skin of the experimental animals. Recovery of microcirculation is associated with a decrease in vascular tone and stimulation of endothelium-dependent vasodilation, caused by simultaneous decrease of catecholamines, endothelin-1 and asymmetric dimethylarginine (ADMA) concentrations in blood serum. At the same time, the administration of liraglutide on the background of insulin-deficiency results in decrease of endothelial cell alteration markers concentration in blood, such as sE-selectin, syndecan-1, and vascular endothelial growth factor (VEGF).

CONCLUSION

Administration of liraglutide leads to the normalization of the carbohydrate metabolism simultaneously with the correction of microcirculation in rats with the absolute insulin deficiency. The demonstrated recovery of microcirculation by liraglutide, which represents an analogue of glucagon-like peptide-1, provides new prospects for its approval as a potential drug for pathogenetic correction of microcirculatory disorders in patients with the type 1 DM.

The Effects of High-Protein Diet and Resistance Training on Glucose Control and Inflammatory Profile of Visceral Adipose Tissue in Rats

High-protein diets (HPDs) are widely accepted as a way to stimulate muscle protein synthesis when combined with resistance training (RT). However, the effects of HPDs on adipose tissue plasticity and local inflammation are yet to be determined. This study investigated the impact of HPDs on glucose control, adipocyte size, and epididymal adipose inflammatory biomarkers in resistance-trained rats. Eighteen Wistar rats were randomly assigned to four groups: normal-protein (NPD; 17% protein total dietary intake) and HPD (26.1% protein) without RT and NPD and HPD with RT. Trained groups received RT for 12 weeks with weights secured to their tails. Glucose and insulin tolerance tests, adipocyte size, and an array of cytokines were determined. While HPD without RT induced glucose intolerance, enlarged adipocytes, and increased TNF-α, MCP-1, and IL1-β levels in epididymal adipose tissue (p < 0.05), RT diminished these deleterious effects, with the HPD + RT group displaying improved blood glucose control without inflammatory cytokine increases in epididymal adipose tissue (p < 0.05). Furthermore, RT increased glutathione expression independent of diet (p < 0.05). RT may offer protection against adipocyte hypertrophy, pro-inflammatory states, and glucose intolerance during HPDs. The results highlight the potential protective effects of RT to mitigate the maladaptive effects of HPDs.

Postprandial responses of circulating energy homeostasis mediators to single macronutrient challenges: influence of obesity and sex hormones

We analysed the influence of obesity, sex and sex steroids on the postprandial responses of circulating energy homeostasis mediators and their receptors to different macronutrient challenges. Seventeen women with polycystic ovary syndrome (PCOS, 8 with obesity), 17 non-hyperandrogenic control women (8 with obesity) and 19 control men (9 with obesity) were submitted, on alternate days, to isocaloric (300 kcal) oral glucose, lipid and protein loads. We evaluated serum ghrelin, leptin, soluble leptin receptor and adiponectin levels and the leukocyte gene expression of ghrelin (GHRL) and its receptor (GHSR), leptin receptor (LEPR) and adiponectin receptor 1 (ADIPOR1) during the macronutrient challenges. The postprandial responses of circulating energy homeostasis mediators were entirely different than those of their related genes. After macronutrient loads the postprandial response of serum energy homeostasis mediators showed a generalized physiological decrease that was blunted in subjects with obesity but was not influenced by sex, sex hormones or PCOS. However, gene expression of GHRL, LEPR and ADIPOR1 showed a marked increase following the ingestion of glucose compared with lipids and proteins, regardless of obesity and sex steroids. The physiological decrease after macronutrient loads, that was deregulated in obesity, did not reflect the acute leukocyte gene expression mainly after glucose, and may suggest a possible role for ghrelin, leptin and adiponectin in the postprandial inflammatory process.

The Effects of Synbiotic Supplementation on Serum Anti-Inflammatory Factors in the Survivors of Breast Cancer with Lymphedema following a Low Calorie Diet: A Randomized, Double-Blind, Clinical Trial

BACKGROUND AND AIM

Breast cancer-related lymphedema (BCRL) is a treatment-related inflammatory complication in breast cancer survivors (BCSs). This study was aimed to evaluate the effect of synbiotic supplementation on serum concentrations of IL-10, TGF-β, VEGF, adiponectin, and edema volume among overweight or obese BCSs with lymphedema following a low-calorie diet (LCD).

METHOD

In a randomized double-blind, controlled clinical trial, 88 obese and overweight BCSs women were randomized to synbiotic supplement (n = 44) or placebo (n = 44) groups and both groups followed an LCD for 10 weeks. Pre- and post-intervention comparisons were made regarding the anti-inflammatory markers which included IL-10, TGF-β, VEGF, adiponectin, edema volume, and anthropometric measurements. Also, the same factors were analyzed to find inter-group disparities.

RESULTS

There were no significant differences among participants in the baseline, except for IL-10 and adiponectin. Post-intervention, no significant differences were observed regarding the anti-inflammatory markers, including IL-10, VEGF, adiponectin, and TGF-β between the groups. After 10 weeks of intervention edema volume significantly decreased in the synbiotic group; additionally, anthropometric measurements (body weight, BMI, body fat percent, and WC) decreased in both groups significantly (P < 0.001 and P < 0.005; respectively).

CONCLUSION

Synbiotic supplementation coupled with an LCD in a 10-week intervention had beneficial effects on increasing the serum TGF-β, IL-10, and adiponectin levels in women with BCRL. It also reduced arm lymphedema volume. Therefore, synbiotic supplementation can be effective in improving health status in BCRL patients.

Effects of Ramadan intermittent fasting on leptin and adiponectin: a systematic review and meta-analysis

OBJECTIVES

Ramadan intermittent fasting may affect whole-body metabolism by affecting appetite-related hormones. This systematic review and meta-analysis aimed to clarify the possible effects of Ramadan intermittent fasting on the main hormones regulating appetite and satiety, including leptin and adiponectin.

METHODS

All English language papers in the PubMed, Scopus, and Embase databases were searched using the keywords "Ramadan fasting", "adiponectin", and "leptin", up to 2020. Data extraction was conducted based on the main data of the studies; the primary outcomes of the analysis were mean changes of adiponectin and leptin levels during the holy month of Ramadan in fasted subjects.

MAIN RESULTS

Data of 16 eligible studies, conducted between 2003 and 2020, were included in the systematic review. Of these, 10 studies with complete data on leptin and adiponectin were included in the meta-analysis. A significant decrease in leptin levels was observed after Ramadan fasting (WMD = -2.28 ng/ml, 95% CI = -3.72, -0.84). Ramadan fasting had no significant effect on adiponectin levels (WMD = 2.19 ng/ml, 95% CI = -0.29, 4.67). Sub-group analysis demonstrated a greater decrease in leptin levels among normal-weight subjects compared to those of overweight/obese subjects (WMD = -4.67 ng/ml, 95% CI = -6.03, -3.31 vs. WMD = -3.43 ng/ml, 95% CI = -5.69, -1.17).

CONCLUSION

Ramadan fasting may decrease leptin levels, especially in normal-weight subjects. There was high heterogeneity, which may be explained by the differences between the wide ranges of study conditions.

Thermogenic Fat: Development, Physiological Function, and Therapeutic Potential

The concerning worldwide increase of obesity and chronic metabolic diseases, such as T2D, dyslipidemia, and cardiovascular disease, motivates further investigations into preventive and alternative therapeutic approaches. Over the past decade, there has been growing evidence that the formation and activation of thermogenic adipocytes (brown and beige) may serve as therapy to treat obesity and its associated diseases owing to its capacity to increase energy expenditure and to modulate circulating lipids and glucose levels. Thus, understanding the molecular mechanism of brown and beige adipocytes formation and activation will facilitate the development of strategies to combat metabolic disorders. Here, we provide a comprehensive overview of pathways and players involved in the development of brown and beige fat, as well as the role of thermogenic adipocytes in energy homeostasis and metabolism. Furthermore, we discuss the alterations in brown and beige adipose tissue function during obesity and explore the therapeutic potential of thermogenic activation to treat metabolic syndrome.

Recent Advances in Panax ginseng C.A. Meyer as a Herb for Anti-Fatigue: An Effects and Mechanisms Review

As an ancient Chinese herbal medicine, Panax ginseng C.A. Meyer (P. ginseng) has been used both as food and medicine for nutrient supplements and treatment of human diseases in China for years. Fatigue, as a complex and multi-cause symptom, harms life from all sides. Millions worldwide suffer from fatigue, mainly caused by physical labor, mental stress, and chronic diseases. Multiple medicines, especially P. ginseng, were used for many patients or sub-healthy people who suffer from fatigue as a treatment or healthcare product. This review covers the extract and major components of P. ginseng with the function of anti-fatigue and summarizes the anti-fatigue effect of P. ginseng for different types of fatigue in animal models and clinical studies. In addition, the anti-fatigue mechanism of P. ginseng associated with enhancing energy metabolism, antioxidant and anti-inflammatory activity is discussed.

Emerging Diabetic Novel Biomarkers of the 21st Century

Diabetes is a growing epidemic with estimated prevalence of infected to reach ~592 million by the year 2035. An effective way to approach is to detect the disease at a very early stage to reduce the complications and improve lifestyle management. Although several traditional biomarkers including glucated hemoglobin, glucated albumin, fructosamine, and 1,5-anhydroglucitol have helped in ease of diagnosis, there is lack of sensitivity and specificity and are inaccurate in certain clinical settings. Thus, search for new and effective biomarkers is a continuous process with an aim of accurate and timely diagnosis. Several novel biomarkers have surged in the present century that are helpful in timely detection of the disease condition. Although it is accepted that a single biomarker will have its inherent limitations, combining several markers will help to identify individuals at high risk of developing prediabetes and eventually its progression to frank diabetes. This review describes the novel biomarkers of the 21st century, both in type 1 and type 2 diabetes mellitus, and their present potential for assessing risk stratification due to insulin resistance that will pave the way for improved clinical outcome.

Beneficial phytoestrogenic effects of resveratrol on polycystic ovary syndromein rat model

AIMS

The effective treatment of polycystic ovary syndrome (PCOS)-related hormonal disorders necessitates the development of novel treatment strategies. Resveratrol is found in certain food products, and is known to exhibit phytoestrogen properties. The present study was to assess whether resveratrol exhibits beneficial phytoestrogenic effects and associated hormonal modulation in a rat model of PCOS.

MATERIALS AND METHODS

This model was established by administering oral letrozole to female Sprague-Dawley (SD) rats prior to randomizing them into control, model and resveratrol treatment groups (40, 80, or 160 mg/kg). Animals were treated for 30 days, after which time ovarian tissues were collected and evaluated via hematoxylin and eosin staining. In addition, serum levels of estradiol and adiponectin were assessed via ELISA, and ovarian expression of nesfatin-1 and aromatase was assessed through RT-PCR and western blotting.

RESULTS

We found that resveratrol administration was associated with increased levels of plasma adiponectin and estradiol levels and restoration of normal ovarian morphology in PCOS model animals. In addition, this treatment was linked to the increased ovarian expression of nesfatin-1 and aromatase at the RNA and protein levels.

CONCLUSIONS

Together things findings suggest that resveratrol may represent an effective tool for treating PCOS owing to its phytoestrogenic properties.

Obese Adipose Tissue as a Driver of Breast Cancer Growth and Development: Update and Emerging Evidence

Obesity is an established risk factor for breast cancer growth and progression. A number of advances have been made in recent years revealing new insights into this link. Early events in breast cancer development involve the neoplastic transformation of breast epithelial cells to cancer cells. In obesity, breast adipose tissue undergoes significant hormonal and inflammatory changes that create a mitogenic microenvironment. Many factors that are produced in obesity have also been shown to promote tumorigenesis. Given that breast epithelial cells are surrounded by adipose tissue, the crosstalk between the adipose compartment and breast epithelial cells is hypothesized to be a significant player in the initiation and progression of breast cancer in individuals with excess adiposity. The present review examines this crosstalk with a focus on obese breast adipose-derived estrogen, inflammatory mediators and adipokines, and how they are mechanistically linked to breast cancer risk and growth through stimulation of oxidative stress, DNA damage, and pro-oncogenic transcriptional programs. Pharmacological and lifestyle strategies targeting these factors and their downstream effects are evaluated for feasibility and efficacy in decreasing the risk of obesity-induced breast epithelial cell transformation and consequently, breast cancer development.

Relationships between depression and anxiety symptoms and adipocyte-derived proteins in postmenopausal women

INTRODUCTION

Studies on the association between adiponectin and leptin and anxiety and depression among postmenopausal women are limited. Therefore, the present study specifically evaluates the mutual relationships between adiponectin and leptin and anxiety and depression in postmenopausal women.

PARTICIPANTS AND DESIGN

In this cross-sectional study, a total of 190 women aged 40-65 years were enrolled. Depression symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (CES-D), and anxiety symptoms were evaluated using the Hamilton Anxiety Rating Scale (HAM-A). Fasting specimens were collected to measure sex hormone, glucose, insulin, and adipokine levels. Multiple linear regression analysis was performed to evaluate the associations between depression and anxiety and adipocyte-derived hormones.

SETTINGS

The study was performed in a hospital medical center.

RESULTS

Among 190 enrolled postmenopausal women, Spearman's rank correlation analysis revealed significant correlations between CES-D and HAM-A (r = 0.715, P < 0.0001), between CES-D and adiponectin (p = 0.009) and leptin (p = 0.015), and between HAM-A and adiponectin (p = 0.01) and leptin (p = 0.001). The subjects with CES-D ≥ 16 and with HAM-A ≥ 18 had higher adiponectin levels than those with CES-D < 16 and HAM-A < 18, respectively. After adjusting for age, body mass index, exercise, alanine amino transferase and parameters of lipid profiles, Log adiponectin levels were found to be significantly associated with both CES-D and HAM-A, and Log leptin levels were only significantly associated with HAM-A.

CONCLUSIONS

The data show that adiponectin and leptin levels are significantly associated with depression and anxiety symptoms. These results suggest that higher adiponectin and lower leptin levels may serve as potential markers related to anxiety and mood in postmenopausal women. More future research that is designed to deal with the important confounders (e.g., population heterogeneity) is needed to investigate comprehensively on these associations.

Differential gut microbiota composition between type 2 diabetes mellitus patients and healthy controls: A systematic review

AIMS

This systematic review summarised the latest findings on differential composition of gut microbiota in T2DM.

METHODS

Literature search was performed using electronic databases. Relevant studies were identified, extracted and assessed for risk of bias. The primary outcome of this systematic review was the composition of gut microbiota in healthy controls and T2DM while the secondary outcomes included the correlation of gut microbiota with metabolic parameters.

RESULTS

Thirteen case-control studies involving 575 T2DM and 840 healthy controls were included. T2DM patients exhibited a marked increase in lactobacilli. Six studies found lactobacilli to predominate the gut of T2DM patients; however, this could be confounded by the types of antihyperglyacemic medications. Conversely, butyrate producers dominate the gut of healthy controls. In T2DM patients, butyrate producers were surprisingly higher in those taking metformin intake than those not taking the drug. Whilst lactobacilli were found to be higher with increased plasma glucose, conflicting correlations were observed between various genera and anthropometric measurements, dietary intake, lipid profiles and inflammatory markers. There were moderate to strong significant positive correlations between the class Clostridia and phylum Firmicutes with pro-inflammatory IFN-γ as well as between Negativicutes and IL-6.

CONCLUSIONS

Altogether, butyrate-producing bacteria are negatively correlated to glycaemic parameters. Lactobacilli are higher in T2DM patients and Firmicutes is correlated with inflammation.

Lactobacillus fermentum MCC2759 and MCC2760 Alleviate Inflammation and Intestinal Function in High-Fat Diet-Fed and Streptozotocin-Induced Diabetic Rats

The growing incidence of type 2 diabetes and obesity has become a worldwide crisis with increased socio-economic burden. Changes in lifestyle and food habits resulting in dysbiosis of the gut microbiota and low-grade inflammation are linked to the rising incidence. The aim of this study was to investigate the effects of potential probiotic Lactobacillus fermentum MCC2759 and MCC2760 on intestinal markers of inflammation using a high-fat diet (HFD)-fed model and a streptozotocin (STZ)-induced diabetic model. Lact. fermentum administration showed improved oral glucose tolerance compared with the model controls of HFD (AUC 1518) and STZ (628.8). Plasma insulin levels improved in the Lact. fermentum treated groups of HFD + MCC2759 (129 ± 4.24 pmol/L) and HFD + MCC2760 (151.5 ± 9.19 pmol/L) in HFD study, while in STZ diabetic study, the insulin levels were normalized with Lact. fermentum administration, for D + MCC2759 (120.5 ± 7.77) and D + MCC2760 (138 ± 5.65 pmol/L) groups. The results showed reduction in inflammatory tone in liver, muscle, and adipose tissues of rats in both models with stimulation of anti-inflammatory IL-10 by real-time quantitative polymerase chain reaction. Additionally, the potential probiotic cultures also displayed normalization of markers related to intestinal barrier integrity (ZO-1), TLR-4 receptor, and insulin sensitivity (GLUT-4, GLP-1, adiponectin). Thus, the results suggest that Lact. fermentum could act as potential probiotic for lifestyle-related disorders such as obesity, diabetes, and metabolic syndrome as both prophylactic and adjunct therapies.

The Edible Brown Seaweed Sargassum horneri (Turner) C. Agardh Ameliorates High-Fat Diet-Induced Obesity, Diabetes, and Hepatic Steatosis in Mice

Sargassum horneri (Turner) C. Agardh (S. horneri) is edible brown seaweed that grows along the coast of East Asia and has been traditionally used as a folk medicine and a local food. In this study, we evaluated the effects of S. horneri on the development of obesity and related metabolic disorders in C57BL/6J mice fed a high-fat diet. S. horneri was freeze-dried, fine-powdered, and mixed with a high-fat diet at a weight ratio of 2% or 6%. Feeding a high-fat diet to mice for 13 weeks induced obesity, diabetes, hepatic steatosis, and hypercholesterolemia. Supplementation of mice with S. horneri suppressed high-fat diet-induced body weight gain and the accumulation of fat in adipose tissue and liver, and the elevation of the serum glucose level. In addition, S. horneri improved insulin resistance. An analysis of the feces showed that S. horneri stimulated the fecal excretion of triglyceride, as well as increased the fecal polysaccharide content. Furthermore, extracts of S. horneri inhibited the activity of pancreatic lipase in vitro. These results showed that S. horneri can ameliorate diet-induced metabolic diseases, and the effect may be partly associated with the suppression of intestinal fat absorption.

N-acetyl cysteine can blunt metabolic and cardiovascular effects via down-regulation of cardiotrophin-1 in rat model of fructose-induced metabolic syndrome

In this study, we investigated the ability of N-acetyl cysteine (NAC) to alleviate the metabolic disorders in fructose-induced metabolic syndrome (MS) in male rats and to examine its protective effect on aortic and cardiac tissues via its influence on cardiotrophin-1 (CT-1) expression. NAC (20 mg/kg b.w./day) was administered to fructose induced MS animals for 12 weeks. Chronic fructose consumption (20% w/v) increased body weight gain, relative heart weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), insulin resistance (IR), and associated with metabolic alterations. Histological and immunohistochemical examination revealed aortic stiffness and myocardial degeneration and fibrosis together with increased CT-1 expression. Treatment with NAC improved IR, SBP, DBP, and mitigated dyslipidaemia and oxidative stress. Additionally, NAC down-regulated CT-1 expression in the heart and aorta. These findings demonstrated the protective effect of NAC against aortic and myocardial degeneration and fibrosis through down-regulation of CT-1 in fructose induced MS animal model.

Metabolic and Energy Imbalance in Dysglycemia-Based Chronic Disease

Metabolic flexibility is the ability to efficiently adapt metabolism based on nutrient availability and requirement that is essential to maintain homeostasis in times of either caloric excess or restriction and during the energy-demanding state. This regulation is orchestrated in multiple organ systems by the alliance of numerous metabolic pathways under the master control of the insulin-glucagon-sympathetic neuro-endocrine axis. This, in turn, regulates key metabolic enzymes and transcription factors, many of which interact closely with and culminate in the mitochondrial energy generation machinery. Metabolic flexibility is compromised due to the continuous mismatch between availability and intake of calorie-dense foods and reduced metabolic demand due to sedentary lifestyle and age-related metabolic slowdown. The resultant nutrient overload leads to mitochondrial trafficking of substrates manifesting as mitochondrial dysfunction characterized by ineffective substrate switching and incomplete substrate utilization. At the systemic level, the manifestation of metabolic inflexibility comprises reduced skeletal muscle glucose disposal rate, impaired suppression of hepatic gluconeogenesis and adipose tissue lipolysis manifesting as insulin resistance. This is compounded by impaired β-cell function and progressively reduced β-cell mass. A consequence of insulin resistance is the upregulation of the mitogen-activated protein kinase pathway leading to a pro-hypertensive, atherogenic, and thrombogenic environment. This is further aggravated by oxidative stress, advanced glycation end products, and inflammation, which potentiates the risk of micro- and macro-vascular complications. This review aims to elucidate underlying mechanisms mediating the onset of metabolic inflexibility operating at the main target organs and to understand the progression of metabolic diseases. This could potentially translate into a pharmacological tool that can manage multiple interlinked conditions of dysglycemia, hypertension, and dyslipidemia by restoring metabolic flexibility. We discuss the breadth and depth of metabolic flexibility and its impact on health and disease.