The role of free fatty acids in the inflammatory and cardiometabolic profile in adolescents with metabolic syndrome engaged in interdisciplinary therapy

The degree of food processing can influence serum fatty acid and lipid profiles in women with severe obesity

Background

The increase in the prevalence of obesity is associated with the increase in the consumption of ultra-processed foods and may be related to the increase in the disorders involving metabolism and the transport and storage of fatty acids.

Objective

To evaluate the effect of processed food consumption according to the degree of processing on the serum fatty acid levels and lipid profile of women with severe obesity.

Methods

This was a cross-sectional study. Data were collected from anthropometric assessments, the food frequency questionnaire (FFQ), and blood tests for lipidogram studies and serum fatty acid measurements. The foods consumed were identified through the FFQ and classified according to the degree of processing based on the NOVA rating, and the frequencies of consumption were transformed into scores, as proposed by Fornés methodology. Data were analyzed using IBM SPSS Statistics, version 21. The significance level for the analysis was set at 5%.

Results

This study included 44 women with a mean age of 40.59 years and mean body mass index of 48.61 kg/m2. An inverse association was observed between the consumption of unprocessed and the occurrence of hypertriglyceridemia (p = 0.021) and levels of triglycerides (p = 0.047), total cholesterol (p = 0.030), and very low-density lipoprotein-cholesterol (p = 0.039). The consumption of processed foods was positively associated with the presence of hypertriglyceridemia (p = 0.044) and omega 6/3 ratio (p = 0.001) and negatively associated with total omega 3 levels (p = 0.011). The consumption of processed foods was positively associated with total cholesterol (p = 0.041) and negatively associated with the omega 3/6 ratio (p = 0.001). A negative correlation was found between the average consumption of ultra-processed foods (at least once a week) and serum level of high-density lipoprotein (p = 0.035).

Conclusion

The consumption of processed and ultra-processed foods was associated with unfavorable lipid profiles and fatty acid levels in women with severe obesity. These results emphasize the importance of promoting the consumption of unprocessed food to mitigate metabolic disorders linked to processed food intake.

Evidence Base Update on Behavioral Treatments for Overweight and Obesity in Children and Adolescents

OBJECTIVE

This review provides an update to a previous Evidence Base Update addressing behavioral treatments for overweight and obesity in children and adolescents.

METHOD

Articles were identified through a systematic search of the biomedical literature in PubMed/MEDLINE (1946-), Elsevier EMBASE (1947-), SCOPUS (1823-), Clarivate Web of Science Core Collection (WOS, 1900-), PsycINFO (1800-), The Cochrane Library and Clinicaltrials.gov published between June 2014 and August 2022.

RESULTS

Family-based treatment (FBT) remains a well-established treatment for overweight and obesity in children and is now well-established in adolescents and toddlers. Parent-only behavioral treatment remains well-established in children and is now well-established among adolescents and children. Possibly effective treatments continue to include FBT-parent only for adolescents, and behavioral weight loss (BWL) with a family component for adolescents, children, and toddlers. Several variations of FBT and BWL can now be considered possibly effective including FBT+motivational interviewing, FBT+social facilitation maintenance, group-based FBT, low-dose FBT, BWL+stress management, and camp-based BWL. Cognitive behavioral treatment (CBT) for adolescents also met criteria for possibly effective treatments. Current research has also established that behavioral treatments can be effectively delivered in alternative settings (e.g. primary care) and through alternative mediums (e.g. telehealth).

CONCLUSIONS

Research continues to support the use of multicomponent lifestyle interventions in accordance with recent recommendations from the American Academy of Pediatrics, the American Psychological Association, and the United State Preventative Services Task Force. However, more work is needed to ensure appropriate access for children with comorbid medical and psychiatric disorders and children from socially, politically, and economically marginalized groups.

Adiponectin/Leptin Ratio as an Index to Determine Metabolic Risk in Patients after Kidney Transplantation

Background and Objectives: It has been confirmed that adiponectin/leptin (A/L) ratio correlates better with cardiometabolic risk factors than hormone levels alone. The aim of our study was to determine the risk of developing post-transplant diabetes mellitus (PTDM) and other metabolic conditions depending on A/L ratio after kidney transplantation (KT). Material and Methods: In a prospective analysis, the studied samples were divided into three groups: control group, prediabetes and PTDM group. Pre-transplantation, at 3, 6 and 12 months after KT, we recorded basic characteristics of donor and recipient. We also monitored levels of adipocytokines and calculated A/L ratio. Results: During observed period, we recorded significant increase in A/L ratio in control group (p = 0.0013), on the contrary, a significant decrease in PTDM group (p = 0.0003). Using Cox regression Hazard model, we identified age at time of KT (HR 2.8226, p = 0.0225), triglycerides at 1 year (HR 3.5735, p = 0.0174) and A/L ratio < 0.5 as independent risk factors for prediabetes and PTDM 1-year post-transplant (HR 3.1724, p = 0.0114). Conclusions: This is the first study to evaluate the relationship between A/L and risk of PTDM and associated metabolic states after KT. We found out that A/L ratio <0.5 is independent risk factor for prediabetes and PTDM 1 year post-transplant.

The relationship between serum fatty acids and depressive symptoms in obese adolescents

Depression and obesity are highly prevalent and are considered inflammatory pathologies; in addition, they are also associated with dietary patterns including types of fatty acids (FA). Changes in the FA composition in the brain are determined by changes in the content and quality of dietary and serum FA. The aim of this study was to verify the relationships between serum-free FA, inflammatory processes and depressive symptoms in obese adolescents. This was a cross-sectional study that analysed a database composed of 138 post-pubertal adolescents. Data regarding the depressive symptoms, body composition, glucose metabolism, lipid profile, FA profile, leptin concentration, as well as adiponectin, IL-A, IL-6, IL-10, TNF-α, C-reactive protein and plasminogen activator inhibitor-1 levels of the subjects were collected. A total of 54·6 % of the adolescents presented with depressive symptoms, and there were positive correlations between depressive symptoms and serum saturated fatty acids (SFA) content, body fat, and inflammatory adipokines, such as leptin, IL-6, and the leptin/adiponectin ratio. Moreover, the content of n-3 polyunsaturated fatty acids (PUFA) was negatively correlated with depressive symptoms, suggesting that eicosatrienoic acid (C20:2n6) and dihomo-γ-linolenic acid (C20:3n-6) are independently associated with depressive symptom scores and can be critical predictors of poor mental health in humans. These results point to the relationship between SFA and depressive symptoms in obese adolescents. However, longitudinal studies are needed to confirm the causality between dietary SFA and depression in obese individuals.

Myristic Acid Supplementation Aggravates High Fat Diet-Induced Adipose Inflammation and Systemic Insulin Resistance in Mice

Saturated fatty acids (SFAs) are considered to be detrimental to human health. One of the SFAs, myristic acid (MA), is known to exert a hypercholesterolemic effect in mice as well as humans. However, its effects on altering adipose tissue (AT) inflammation and systemic insulin resistance (IR) in obesity are still unclear. Here, we sought to determine the effects of a high fat (HF) diet supplemented with MA on obesity-associated metabolic disorders in mice. Wild-type C57BL/6 mice were fed a HF diet in the presence or absence of 3% MA for 12 weeks. Plasma lipids, plasma adipokines, AT inflammation, systemic IR, glucose homeostasis, and hepatic steatosis were assessed. The body weight and visceral adipose tissue (VAT) mass were significantly higher in mice receiving the HF+MA diet compared to HF diet-fed controls. Plasma total cholesterol levels were marginally increased in HF+MA-fed mice compared to controls. Fasting blood glucose was comparable between HF and HF+MA-fed mice. Interestingly, the plasma insulin and HOMA-IR index, a measure of insulin resistance, were significantly higher in HF+MA-fed mice compared to HF controls. Macrophage and inflammatory markers were significantly elevated in the AT and AT-derived stromal vascular cells upon MA feeding. Moreover, the level of circulating resistin, an adipokine promoting insulin resistance, was significantly higher in HF+MA-fed mice compared with HF controls. The insulin tolerance test revealed that the IR was higher in mice receiving the MA supplementation compared to HF controls. Moreover, the glucose tolerance test showed impairment in systemic glucose homeostasis in MA-fed mice. Analyses of liver samples showed a trend towards an increase in liver TG upon MA feeding. However, markers of oxidative stress and inflammation were reduced in the liver of mice fed an MA diet compared to controls. Taken together, our data suggest that chronic administration of MA in diet exacerbates obesity-associated insulin resistance and this effect is mediated in part, via increased AT inflammation and increased secretion of resistin.

Fat-free/lean body mass in children with insulin resistance or metabolic syndrome: a systematic review and meta-analysis

BACKGROUND

Lean / Fat Free Body Mass (LBM) is metabolically involved in active processes such as resting energy expenditure, glucose uptake, and myokine secretion. Nonetheless, its association with insulin sensitivity / resistance / glucose tolerance and metabolic syndrome remains unclear in childhood.

METHODS

The current investigation aimed to examine the differences in fat-free mass /lean body mass according to the presence of insulin sensitivity/insulin resistance/glucose tolerance/metabolic syndrome in children. A systematic search was carried out in Medline/PubMed, Embase, Scopus, Web of Science, and SciELO, covering the period from each database's respective start to 21 June 2021. Two researchers evaluated 7111 studies according to the inclusion criteria: original human studies, written in English or Spanish, evaluating fat-free mass/lean body mass in children and adolescents including both with and without insulin sensitivity/insulin resistance /glucose tolerance and metabolic syndrome and reported the differences between them in terms of fat free mass/lean body mass. The results of the studies were combined with insulin sensitivity, insulin, resistance, glucose tolerance and metabolic syndrome. The standardized mean difference (SMD) in each study was calculated and combined using the random-effects model. Heterogeneity between studies was tested using the index of heterogeneity (I2), leave-one-out sensitivity analyses were performed, and publication bias was assessed using the Egger and Begg tests.

RESULTS

Finally, 15 studies which compared groups defined according to different glucose homeostasis criteria or metabolic syndrome out of 103 eligible studies were included in this systematic review and 12 studies in the meta-analysis. Meta-analysis showed lower fat-free mass/lean body mass percentage in participants with insulin resistance/glucose tolerance/metabolic syndrome (SMD -0.47; 95% CI, - 0.62 to - 0.32) while in mass units (kg), higher values were found in the same group (SMD, 1.01; 95% CI, 0.43 to 1.60).

CONCLUSIONS

Our results identified lower values of fat-free mass/lean body mass (%) in children and adolescents with insulin resistance/glucose tolerance/metabolic syndrome and higher values of fat-free mass/lean body mass when these are expressed in kg. The evidence of the impact of lean mass on children's glucose homeostasis or metabolic syndrome is limited, so future studies research should focus on explaining the effect of fat-free mass/lean body mass on different metabolic outcomes. Moreover, it may be interesting to evaluate the quality (muscle density) or functional (muscle strength) outcomes in addition to both absolute (kg) and relative (%) values in future studies. The systematic review was prospectively registered at PROSPERO (registration number CRD42019124734; available at: http://www.crd.york.ac.uk/prospero [accessed: 05 April 2019]).

Effects of an interdisciplinary weight loss program on fibroblast growth factor 21 and inflammatory biomarkers in women with overweight and obesity

Objective

To investigate the effects of an interdisciplinary intervention on biomarkers of inflammation and their relationship with fibroblast growth factor 21 (FGF21) concentrations in women with overweight and obesity.

Methods

Thirty-one women were enrolled in a 12-week interdisciplinary weight loss program delivered by a team comprising an endocrinologist, nutritionist and exercise physiologist. Body composition; anthropometric measures; metabolic and inflammatory markers including adiponectin, leptin, and atrial natriuretic peptide (ANP) were assessed at baseline and post-therapy. The homeostasis model assessment of insulin resistance (HOMA-IR) and the homeostasis model assessment of adiponectin (HOMA-AD) were calculated. The participants were divided into two groups: those with increased FGF21, and those with decreased FGF21.

Results

The sample comprised women aged 32 ± 5 years with a body mass index of 33.64 ± 3.49 kg/m². Body weight, waist circumference and leptin concentration were decreased in the whole sample after therapy. However, only the group with an increase in FGF21 concentration presented significant improvements in adiponectin concentration and adiponectin/leptin ratio. Moreover, although there was a reduction of leptin in both groups, it was greater in the increased FGF21 groups. There was a reduction in ANP in the decreased FGF21 group.

Conclusion

Changes in FGF21 concentrations were different among the women participating in the weight loss program, with some having increased levels and some reduced levels. Furthermore, improvements in adiponectin and the adiponectin/leptin ratio were found only in the group with increased FGF21 concentration.

Improved fatty acid profile reduces body fat and arterial stiffness in obese adolescents upon combinatorial intervention with exercise and dietary restriction

Objective

In order to examine the effect of 4-week combinatorial intervention with exercise training and dietary restriction on serum fatty acids, and to explore the correlation of intervention-induced improvement of serum fatty acid profile with the reduction of body fat and arterial stiffness.

Methods

Thirty-three obese adolescents were randomized into the intervention (n = 19) and control (n = 14) groups. The participants from the intervention group were subjected to 4-week combinatorial intervention with exercise training and dietary restriction while the participants from the control group maintained regular activities and diet habits. Anthropometry, serum fatty acids and arterial stiffness were measured before and after 4-week intervention.

Results

The participants upon combinatorial intervention revealed the improved body compositions and serum fatty acid profile, and reduced arterial stiffness when compared with their basal levels and the control participants (p < 0.05). Moreover, the decrease in myristic acid, stearic acid, arachidic acid, behenic acid, palmitoleic acid, and dihomo-γ-linolenic acid, was associated with the reduction in body fat. A positive correlation between arachidonic acid and left brachial ankle pulse velocity was observed, and the increase in docosahexaenoic acid was associated with the reduction of left brachial ankle pulse wave velocity and the enhancement of right ankle brachial index.

Conclusion

The 4-week combinatorial intervention is a useful strategy to improve serum fatty acid profile along with the reduction of body fat and arterial stiffness in obese adolescents.

The Novel Antitumor Compound HCA Promotes Glioma Cell Death by Inducing Endoplasmic Reticulum Stress and Autophagy

Glioblastoma (GBM) is the most common and aggressive type of primary brain tumor in adults, and the median survival of patients with GBM is 14.5 months. Melitherapy is an innovative therapeutic approach to treat different diseases, including cancer, and it is based on the regulation of cell membrane composition and structure, which modulates relevant signal pathways. Here, we have tested the effects of 2-hydroxycervonic acid (HCA) on GBM cells and xenograft tumors. HCA was taken up by cells and it compromised the survival of several human GBM cell lines in vitro, as well as the in vivo growth of xenograft tumors (mice) derived from these cells. HCA appeared to enhance ER stress/UPR signaling, which consequently induced autophagic cell death of the GBM tumor cells. This negative effect of HCA on GBM cells may be mediated by the JNK/c-Jun/CHOP/BiP axis, and it also seems to be provoked by the cellular metabolite of HCA, C21:5n-3 (heneicosapentaenoic acid). These results demonstrate the efficacy of the melitherapeutic treatment used and the potential of using C21:5n-3 as an efficacy biomarker for this treatment. Given the safety profile in animal models, the data presented here provide evidence that HCA warrants further clinical study as a potential therapy for GBM, currently an important unmet medical need.

A High-Fat Diet Induces Lower Systemic Inflammation than a High-Carbohydrate Diet in Mice

Background: We previously established that male Swiss mice (Mus musculus) receiving a high-fat diet (HFD) during 8 weeks exhibit similar caloric ingestion and body weight (grams) compared with mice fed a high-carbohydrate diet (HCD). HFD mice exhibit a lower inflammatory state than an HCD in the liver, skeletal muscle, and brain. In addition, we demonstrated that HFD and HCD modulated fatty acids (FA) composition in these tissues. In this study, our objective was to compare HFD mice and HCD mice in terms of systemic inflammation. Methods: Saturated FA (SFA), monounsaturated FA, omega-6 polyunsaturated FA (n-6 PUFA), and n-3 PUFA were evaluated at the time points 0, 1, 7, 14, 28, and 56 days after starting the administration of the diets. We investigated n-6 PUFA:n-3 PUFA, SFA:n-3 PUFA, palmitic acid:α-linolenic acid (ALA), and myristic acid:docosahexaenoic acid (DHA) ratios as potential serum biomarkers of systemic inflammation. We also measured the serum levels of basic fibroblast growth factor, granulocyte-macrophage colony-stimulating factor (GM-CSF), inducible protein 10 (IP-10), interferon gamma (IFN-γ), interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-13, IL-17, macrophage inflammatory protein-1α (MIP-1-α), monocyte chemotactic protein 1 (MCP-1), monokine induced by IFN-γ (MIG), and tumor necrosis factor α (TNF-α). Results: The HFD group had lower (P < 0.05) n-6 PUFA:n-3 PUFA, palmitic acid:ALA, myristic acid:DHA ratios, and lower plasma levels of proinflammatory cytokines (IFN-γ, MIG, GM-CSF, and IL-6). Conclusion: The HFD mice showed lower systemic inflammation compared with a caloric ingestion-body weight-matched control HCD mice.

Prevalence of Metabolic Syndrome and Impaired Glucose Metabolism among 10- to 17-Year-Old Overweight and Obese Lithuanian Children and Adolescents

BACKGROUND

Overweight (Ow) and obesity among adults and children increases the risk of metabolic consequences. Metabolic syndrome (MS) and impaired glucose metabolism are well-known risk factors for cardiovascular diseases and type 2 diabetes. The aim of this study was to evaluate the prevalence of MS and impaired glucose metabolism among Ow and obese (Ob) children and adolescents (aged 10-17 years) in Lithuania, and to evaluate the associations between insulin resistance (IR) indices and anthropometric parameters as well as metabolic disturbances.

METHODS

The study population consisted of 344 OwOb children and adolescents of all pubertal stages. Oral glucose tolerance tests (OGTTs), IR and β cell function indices, lipid profile, and anthropometric parameters of all subjects were analyzed. MS was defined according to the International Diabetes Federation consensus guidelines.

RESULTS

MS was found in 21.3% of the OwOb children and adolescents, and 12.1% had impaired glucose metabolism (6.9% with impaired fasting glucose, 4.5% with impaired glucose tolerance, and 0.6% with type 2 diabetes). IR was directly related to body mass index and waist circumference, waist-to-height and waist-to-hip ratios, and sum of skin-fold thicknesses. Children with MS were more insulin-resistant, had higher odds ratio for prediabetes and had a more disturbed lipid profile than subjects without MS. Moreover, total cholesterol and low-density lipoprotein cholesterol levels were significantly lower in the more mature OwOb adolescents.

CONCLUSION

MS and lipid profile disturbances are common in OwOb children and adolescents. MS is directly associated with IR. Therefore, OwOb children and adolescents should be carefully followed up for metabolic abnormalities during late childhood as these can persist into adulthood.

2-Hydroxy-Docosahexaenoic Acid Is Converted Into Heneicosapentaenoic Acid via α-Oxidation: Implications for Alzheimer's Disease Therapy

Alzheimer’s disease (AD) is a neurodegenerative disease with as yet no efficient therapies, the pathophysiology of which is still largely unclear. Many drugs and therapies have been designed and developed in the past decade to stop or slow down this neurodegenerative process, although none has successfully terminated a phase-III clinical trial in humans. Most therapies have been inspired by the amyloid cascade hypothesis, which has more recently come under question due to the almost complete failure of clinical trials of anti-amyloid/tau therapies to date. To shift the perspective for the design of new AD therapies, membrane lipid therapy has been tested, which assumes that brain lipid alterations lie upstream in the pathophysiology of AD. A hydroxylated derivative of docosahexaenoic acid was used, 2-hydroxy-docosahexaenoic acid (DHA-H), which has been tested in a number of animal models and has shown efficacy against hallmarks of AD pathology. Here, for the first time, DHA-H is shown to undergo α-oxidation to generate the heneicosapentaenoic acid (HPA, C21:5, n-3) metabolite, an odd-chain omega-3 polyunsaturated fatty acid that accumulates in cell cultures, mouse blood plasma and brain tissue upon DHA-H treatment, reaching higher concentrations than those of DHA-H itself. Interestingly, DHA-H does not share metabolic routes with its natural analog DHA (C22:6, n-3) but rather, DHA-H and DHA accumulate distinctly, both having different effects on cell fatty acid composition. This is partly explained because DHA-H α-hydroxyl group provokes steric hindrance on fatty acid carbon 1, which in turn leads to diminished incorporation into cell lipids and accumulation as free fatty acid in cell membranes. Finally, DHA-H administration to mice elevated the brain HPA levels, which was directly and positively correlated with cognitive spatial scores in AD mice, apparently in the absence of DHA-H and without any significant change in brain DHA levels. Thus, the evidence presented in this work suggest that the metabolic conversion of DHA-H into HPA could represent a key event in the therapeutic effects of DHA-H against AD.

Relationships of inflamm-aging with circulating nutrient levels, body composition, age, and pituitary pars intermedia dysfunction in a senior horse population

Similarly to aged humans, senior horses (≥20 years) exhibit chronic low-grade inflammation systemically, known as inflamm-aging. Inflamm-aging in the senior horse has been characterized by increased circulating inflammatory cytokines as well as increased inflammatory cytokine production by lymphocytes and monocytes in response to a mitogen. Little is currently known regarding underlying causes of inflamm-aging. However, senior horses are also known to present with muscle wasting and often the endocrinopathy pituitary pars intermedia dysfunction (PPID). Despite the concurrence of these phenomena, the relationships inflamm-aging may have with measures of body composition and pituitary function in the horse remain unknown. Furthermore, nutrition has been a focus of research in an attempt to promote health span as well as life span in senior horses, with some nutrients, such as omega-3 fatty acids, having known anti-inflammatory effects. Thus, an exploratory study of a population of n = 42 similarly-managed senior horses was conducted to determine relationships between inflamm-aging and measures of circulating nutrients, body composition, age, and PPID. Serum was collected to determine vitamin, mineral, and fatty acid content. Peripheral blood mononuclear cells were also isolated to determine inflammatory cytokine production of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) following stimulation with a mitogen, as well as to determine gene expression of interleukin(IL)-1β, IL-6, IL-10, IFN-γ, and TNF-α. Serum IL-6 and C-reactive protein were determined by enzyme-linked immunosorbent assay. Whole blood was collected for hematological and biochemical analysis. Body composition was evaluated via ultrasound and muscle scoring for all 42 horses as well as by deuterium oxide dilution for a subset of n = 10 horses. Pituitary function was evaluated by measuring basal adrenocorticotropin hormone concentrations as well as by thyrotropin releasing hormone stimulation testing (to determine PPID status). Results showed various relationships between inflammatory markers and the other variables measured. Most notably, docosadienoic acid (C22:2n6c), docosapentaenoic acid (C22:5n3c), and folate were positively associated with numerous inflammatory parameters (P ≤ 0.05). Although no relationships were found between inflamm-aging and PPID, being positive for PPID was negatively associated with vitamin B12 (P ≤ 0.01). No relationships between inflammation and body composition were found. Even within this senior horse population, age was associated with multiple parameters, particularly with numerous inflammatory cytokines and fatty acids. In summary, inflamm-aging exhibited relationships with various other parameters examined, particularly with certain fatty acids. This exploratory study provides insights into physiological changes associated with inflamm-aging in the senior horse.

Adipocytokines in Non-functional Adrenal Incidentalomas and Relation with Insulin Resistance Parameters

OBJECTIVE

Adrenal incidentalomas are diagnosed incidentally during radiological screenings and require endocrinological investigations for hormonal activity and malignancy. In certain studies, it has been reported that non-functional incidentalomas can be associated with high adipocytokines levels affecting the insulin resistance just like the adipose tissue with metabolic syndrome. Here, we studied serum adipocytokine levels including leptin, resistin, visfatin, omentin 1 and adiponectin in subjects with non-functional adrenal incidentaloma.

METHODS

Seventy-seven (77) patients (Female 57; Male 20) with non-functional adrenal incidentaloma (NFAI) were enrolled in the study. All patients' past medical history, physical examination including Body Mass Index (BMI) and waist circumference were performed. The patients' demographic, radiologic, hormonal and biochemical parameters were recorded. To compare the parameters, a control group (CG) (n=30) was formed from healthy volunteers. Both groups were matched for age, gender, waist circumference and BMI. Serum adipocytokines including leptin, resistin, visfatin, omentin 1 and adiponectin were measured quantitatively by ELISA. Fasting plasma glucose, insulin, sodium, potassium, cortisol, adrenocorticotropic hormone (ACTH), lipid profiles, and dehidroepiandrostenedion sulphate (DHEAS) were measured.

RESULTS

Mean age of the patients was 52.2±10.4 years. BMI and waist circumference of NFAI patients were 26.2±3.28 kg/m2 and 90.2 ±7.5cm, respectively. The mean age of the control group was 48.0±8.16. BMI and waist circumference values for the control group were 25.3±3.5 kg/m2 and 88.3±9.6 cm, respectively. When both groups were compared for age, gender, BMI and waist circumference were non-significant (p>0.05). Serum fasting insulin, total cholesterol, LDL, triglyceride levels of the NFAI group were significantly higher than CG (p<0.05). The insulin resistance index (HOMAIR) values of the NFAI subjects were found to be higher than CG (2.5±1.37, 1.1±0.3 p=0.00). Resistin level of NFAI group was also found to be higher than CG [286.6 ng/L vs. 197 ng/L; (P=0,00)], respectively. Leptin levels of NFAI were significantly higher than CG [441.1 ng/mL vs. 186.5 ng/mL; (P=0.00)] respectively. Adiponectin levels were significantly reduced in the NFAI group than in the CG [10.7 mg/L vs. 30.8 mg/L; (P=0.00)]. Comparision of visfatin and omentin levels was nonsignificant.

CONCLUSION

In this study on subjects with non-functional adrenal incidentaloma, we found not only significantly decreased serum adiponectin levels but also increased leptin, resistin levels as well as dyslipidemia, hypertension and high insulin resistance index. All of which could affect insulin resistance and cardiovascular risk factors. The underlying mechanisms of these findings are unknown, hence further studies are needed.

Fibronectin Type III Domain Containing 4 attenuates hyperlipidemia-induced insulin resistance via suppression of inflammation and ER stress through HO-1 expression in adipocytes

Although Fibronectin Type III Domain Containing 4 (FNDC4) has been reported to be involved in the modulation of inflammation in macrophages, its effects on inflammation and insulin resistance in adipose tissue are unknown. In the current study, we investigated the effects of FNDC4 on hyperlipidemia-mediated endoplasmic reticulum (ER) stress, inflammation, and insulin resistance in adipocytes via the AMP-activated protein kinase (AMPK)/heme oxygenase-1 (HO-1)-mediated pathway. Hyperlipidemia-induced nuclear factor κB (NFκB), inhibitory κBα (IκBα) phosphorylation, and pro-inflammatory cytokines such as TNFα and MCP-1 were markedly mitigated by FNDC4. Furthermore, FNDC4 treatment attenuated impaired insulin signaling in palmitate-treated differentiated 3T3-L1 cells and in subcutaneous adipose tissue of HFD-fed mice. FNDC4 administration ameliorated glucose intolerance and reduced HFD-induced body weight gain in mice. However, FNDC4 treatment did not affect calorie intake. Additionally, treatment with FNDC4 attenuated hyperlipidemia-induced phosphorylation or expression of ER stress markers such as IRE-1, eIF2α, and CHOP in 3T3-L1 adipocytes and in subcutaneous adipose tissue of mice. FNDC4 treatment stimulated AMPK phosphorylation and HO-1 expression in 3T3-L1 adipocytes and in subcutaneous adipose tissue of mice. siRNA-mediated suppression of AMPK and HO-1 abrogated the suppressive effects of FNDC4 on palmitate-induced ER stress, inflammation, and insulin resistance. In conclusion, our results show that FNDC4 ameliorates insulin resistance via AMPK/HO-1-mediated suppression of inflammation and ER stress, indicating that FNDC4 may be a novel therapeutic agent for treating insulin resistance and type 2 diabetes.

A high concentration of fatty acids induces TNF-α as well as NO release mediated by the P2X4 receptor, and the protective effects of puerarin in RAW264.7 cells

Circulating levels of free fatty acids (FFAs) are often found to be increased in patients with type 2 diabetes mellitus (T2DM) and metabolic syndrome (MS). High plasma FFA levels may give rise to maladaptive macrophage activation and promote inflammatory responses, which has been proposed as a potential mechanism for the development of DM and MS. P2X4 receptor (P2X4R), a ligand-gated cation channel activated by extracellular adenosine triphosphate (ATP), plays a primary role in the regulation of inflammatory responses. Puerarin has been reported to possess potential anti-inflammatory activity. However, the anti-inflammatory activity of puerarin and the underlying molecular mechanisms in a setting of a high concentration of FFAs remain unknown. In this study, we found that a high concentration of FFAs increased the expression of P2X4R, cytosolic Ca²⁺ concentration and the phosphorylation of extracellular signal-regulated kinase (ERK) and induced the expression of tumor necrosis factor (TNF)-α and inducible nitric oxide synthase (iNOS) mRNA and the release of TNF-α and nitric oxide (NO) in RAW264.7 macrophages. Such a high concentration FFA-induced inflammation may be reversed by the P2X4R selective antagonist 5-BDBD, which manifests the important role of P2X4R in the TNF-α and NO release caused by the high concentration of FFAs in RAW264.7 cells. Molecular docking data showed that puerarin could interfere with the activation of P2X4R by forming hydrogen bonding towards residue Arg267, an important residue essential for the canonical activation of P2X4R. Treatment with puerarin dose-dependently reduced high concentration FFA-elevated P2X4R expression and inhibited P2X4R-mediated inflammatory signalling, including high concentration FFA-evoked [Ca²⁺]_i, ERK phosphorylation, expression of TNF-α and iNOS mRNA and release of TNF-α and NO. Our findings emphasize the critical role of P2X4R in high concentration FFA-induced TNF-α and NO release of RAW264.7 macrophages. Puerarin notably counteracts these high concentration FFA-induced adverse effects through its inhibition of P2X4R expression and P2X4R-mediated inflammatory signalling.

Adiponectin-leptin ratio: A promising index to estimate adipose tissue dysfunction. Relation with obesity-associated cardiometabolic risk

Obesity is currently the most extended metabolic disturbance worldwide favoring the development of cardiometabolic alterations such as type 2 diabetes, hypertension, and dyslipidemia. Obesity and the metabolic syndrome (MS) are characterized by an increase in circulating leptin concentrations, in parallel to a decrease in blood levels of adiponectin. Consequently, the adiponectin/leptin ratio has been suggested as a maker of adipose tissue dysfunction. This emerging biomarker correlates with insulin resistance better than adiponectin or leptin alone, or even HOMA and is decreased with increasing number of metabolic risk factors having been proposed as a predictive marker for the MS. Moreover, the adiponectin/leptin ratio is negatively correlated with markers of low-grade chronic inflammation. In this sense, an increase in this ratio has been related with reduced atherosclerosis risk as well as with a decreased risk of some types of cancer in epidemiological studies. In this commentary we propose new cutoffs to estimate obesity- and MS-associated cardiometabolic risk according to the adiponectin/leptin ratio and discuss different therapeutic strategies to increase this promising biomarker of metabolic risk.