Metabolic shift precedes the resolution of inflammation in a cohort of patients undergoing bariatric and metabolic surgery

Myokines as potential mediators of changes in glucose homeostasis and muscle mass after bariatric surgery

Myokines are bioactive peptides released by skeletal muscle. Myokines exert auto-, para-, or endocrine effects, enabling them to regulate many aspects of metabolism in various tissues. However, the contribution of myokines to the dramatic changes in glucose homeostasis and muscle mass induced by bariatric surgery has not been established. Our review highlights that myokines such as brain-derived neurotrophic factor (BDNF), meteorin-like protein (Metrnl), secreted protein acidic and rich in cysteine (SPARC), apelin (APLN) and myostatin (MSTN) may mediate changes in glucose homeostasis and muscle mass after bariatric surgery. Our review also identifies myonectin as an interesting candidate for future studies, as this myokine may regulate lipid metabolism and muscle mass after bariatric surgery. These myokines may provide novel therapeutic targets and biomarkers for obesity, type 2 diabetes and sarcopenia.

Rheumatic Diseases Following Metabolic and Bariatric Surgery: A Systematic Review and Meta-Analysis

Metabolic and bariatric surgery (MBS) has been associated with weight reduction and obesity complications improvement. However, there is no clear evidence of the extent and consistency of the effects of this procedure on rheumatic diseases. This study aims to conduct a meta-analysis to address the impact of MBS on rheumatic diseases. We searched PubMed, Cochrane, and Embase for studies reporting the prevalence of rheumatic diseases, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the medication use after MBS. We conducted a random-effects meta-analysis using odds ratios (OR) and mean differences (MD) with 95% confidence intervals (CI). P-values < 0.05 were considered statistically significant. We included 28 studies comprising 43,421 patients, with 13,347 patients with rheumatic diseases. The prevalence of osteoarthritis (OA), rheumatoid arthritis, and psoriatic arthritis was significantly reduced after MBS (OR 0.20; 95% CI 0.12 to 0.33; P = 0.01). The WOMAC index for patients with OA had a statistically significant overall reduction after MBS at 6 months (MD - 20.60 points; 95% CI - 28.73 to - 12.47; P < 0.01) and at 12 months (MD - 15.88 points; 95% CI - 19.09 to - 12.66; P < 0.01). Medication use significantly decreased after MBS, both at the follow-up beyond 2 years (OR 0.49; 95% CI 0.35 to 0.69; P < 0.01) and up to 2 years (OR 0.32; 95% CI 0.15 to 0.69; P < 0.01). In this meta-analysis, we found a significant decrease in the prevalence of rheumatic diseases, improvements in the WOMAC index, and reduced medication use among patients undergoing MBS.

Waist Circumference Is a Strong Predictor of a Positive Outcome Evaluated One Year After Sleeve Gastrectomy

BACKGROUND

Bariatric surgeries, such as laparoscopic sleeve gastrectomy (LSG), not only result in significant weight loss but also improve the inflammatory state in obese patients. This study aimed to investigate the effects of LSG on weight loss and inflammation status in bariatric patients 1-year post-procedure.

METHODS

This prospective cohort study was conducted from September 2022 to May 2024. Fifty obese adults were enrolled for LSG. All patients underwent assessments of body measurements, as well as levels of interleukin-6 (IL-6) and interleukin-10 (IL-10) at baseline, and then at 3 and 12 months post-surgery.

RESULTS

Twelve months post-surgery, body measurements showed a significant reduction, with a median excess weight loss (%EWL) of 56.8%, indicating the clinical success of the bariatric procedure. %EWL showed a strong correlation with waist circumference (R = - 0.738, p < 0.00001). A logistic regression model indicated that a reduction of just 1 cm in initial waist circumference increases the likelihood of a positive outcome in laparoscopic sleeve gastrectomy by 12%. Moreover, a significant increase was observed for IL-10 (p < 0.0001), simultaneously with a significant decrease in IL-6 (p < 0.0001).

CONCLUSIONS

This study provides valuable evidence supporting the benefits of laparoscopic sleeve gastrectomy for both weight loss and reducing inflammation. Waist circumference emerged as a strong predictor of metabolic success 1-year post-surgery, while increased IL-10 levels signaled positive immunological changes.

Metabolomic Changes Associated With the Change in HVPG After DAAs Therapy in HCV Cirrhotic Patients

BACKGROUND AND AIMS

In response to direct-acting antivirals (DAAs) therapy, patients who experience a decrease in hepatic venous pressure gradient (HVPG) considerably reduce liver complications and have increased survival. This study aimed to assess the metabolomic changes associated with the changes in HVPG from the start of DAA therapy until 48 weeks after effective DAA therapy in patients with advanced HCV-related cirrhosis.

METHODS

We carried out a multicenter longitudinal study in 31 patients with advanced hepatitis C virus (HCV)-related cirrhosis. We performed a non-targeted metabolomic analysis using gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry, as well as analysis of inflammation-related biomarkers using Luminex technology. The statistical analysis was performed by Generalised Linear Mixed-effects Models (GLMM), correcting for multiple testing.

RESULTS

We found that increases of 2,3-butanediol (AMR = 1.15; q-value = 0.023) and taurocholic acid (AMR = 1.06; q-value < 0.001) were significantly associated with increases in HVPG and inflammatory biomarker levels from before DAA therapy to one year after completion of successful HCV treatment.

CONCLUSIONS

These metabolites have a potential role as indicators of portal hypertension evolution.

Bariatric surgery modulates plasma levels of antibodies against angiotensin II type 1 and endothelin 1 type A receptor in severe obesity

PURPOSE

The contribution of endothelial-targeted autoantibodies against the angiotensin II type 1 receptor (anti-AT1R) and the anti-endothelin 1 type A receptor (anti-ETAR1) has been proposed in the development of cardiovascular diseases. However, no data have been reported yet in obesity. In this observational study we evaluated the relationship between anthropometric and metabolic parameters and anti-AT1R and anti-ETAR1 concentrations in a cohort of patients with severe obesity and associated comorbidities undergoing bariatric surgery.

METHODS

Clinical evaluation and metabolic assessment were performed in 36 subjects referring to our Center for the Study and Integrated Treatment of Obesity at the University Hospital of Padova. Circulating inflammatory adipocytokines and the endothelial dysfunction marker asymmetric dimethylarginine (ADMA) were evaluated; plasma levels of anti-AT1R and anti-ETAR1 were also determined. 10 normal-weight subjects were considered as a control group. 29 patients out of 36 were re-evaluated after surgery.

RESULTS

With respect to normal-weight controls patients showed significantly higher plasma levels of anti-AT1R (28 ± 20.4 vs 13.5 ± 2.8 U/mL, p < 0.005) and ADMA (0.8 ± 0.1 vs 0.54 ± 0.08 uM/L, p < 0.0001) but not anti-ETAR1 (14.2 ± 1.3 vs 13.3 ± 2 U/mL, p = 0.1). Anti-AT1R concentration showed an increasing trend with the worsening of glycemic status, while the presence of arterial hypertension among the patients did not affect autoantibodies levels. One year after surgery, a significant improvement in body weight and metabolic and inflammatory parameters was observed, along with a significant reduction of anti-AT1R (28.1 ± 20.4 U/mL vs 22.6 ± 16 U/mL, p < 0.05) and anti-ETAR1 (14.2 ± 1.3 U/L vs 13 ± 1.6 U/L, p < 0.01).

CONCLUSIONS

Subjects with obesity present higher plasma levels of anti-AT1R which are more related to glycemic profile than blood pressure levels, and are reduced by bariatric surgery. Considering the detrimental effects of these autoantibodies on vascular health, they should be assessed as potential biomarkers in obesity and metabolic diseases.

Normalization of WISP1 circulating level and tissue expression following metabolic and bariatric surgery using rat model

Wingless-type inducible signaling pathway protein-1 (WISP1) is a newly recognized adipokine, associated with obesity and type 2 diabetes (T2DM). This study aimed to investigate the effect of metabolic and bariatric surgery (MBS) on WISP1 circulating (serum) levels and tissue expression using rat models. We initially investigated whether WISP1 circulating levels were altered between the T2DM and normal rats. After confirmation, Sprague-Dawley (SD) rats were obtained and randomly divided as follows: Roux-en-Y gastric bypass (RYGB) group (n = 10), sleeve gastrectomy (SG) group (n = 10), SHAM group (n = 10), and normal control (NC) group (n = 10). Rats were followed for 8 weeks postoperatively. Preoperative and postoperative WISP1 circulating (serum) levels, glucose tolerance test (OGTT), insulin tolerance test (ITT), postoperative WISP1 expression (visceral adipose tissue, VAT; and skeletal muscle, SM), body weight, food intake, and fasting blood glucose levels were recorded. MBS significantly induced glucose control and weight loss. At postoperative week 8, WISP1 serum levels decreased in the MBS groups (P < 0.05); furthermore, WISP1 expression in VAT and SM significantly decreased in the RYGB and SG groups than SHAM (P < 0.05, and P < 0.05, respectively). Whereas the difference in the expression level between SG and RYGB did not amount to statistical significance (P > 0.05). MBS significantly decreased WISP1 serum levels, tissue expression in the VAT, and SM. As WISP1 is a regulator of low-grade inflammation associated with obesity and T2DM, further studies are needed to explore its relevance in MBS.

Sleeve-gastrectomy results in improved metabolism and a massive stress response of the liver proteome in a mouse model of metabolic dysfunction-associated steatohepatitis

Background

Bariatric surgery has been shown to improve the histopathological findings in patients with obesity and metabolic dysfunction-associated steatohepatitis, but there are also reports about non-responders or progressive disease after bariatric interventions. Therefore, it is of utmost importance to understand the pathophysiological processes in the liver after bariatric surgery.

Materials and methods

In the present study, 4 weeks old male C57/Bl6 mice were fed a Western Diet to induce metabolic dysfunction-associated steatohepatitis and sleeve-gastrectomy (SG), or sham operation in the pair-fed and ad libitum control group were performed. Mice were observed for two or eight weeks after surgery and metabolic assessment was performed throughout the experiment. Histopathology, flow cytometry and proteomic analyses were conducted to evaluate hepatic inflammation, liver metabolism and affected signaling pathways.

Results

Weight loss was higher, and metabolism significantly improved after SG. Two weeks after SG major inflammatory and regulatory disturbances in the liver were observed. The proportion of hepatic CD3+NK1.1+ cells were decreased, and proteins involved in apoptosis like Fas, Casp1 and Casp9 or in the acute phase response were upregulated in SG mice. These disturbances decreased in the long-term and we observed an increase of many proteins involved in lipid metabolism eight weeks following SG.

Conclusions

The rapid weight loss and decrease of hepatic fat after SG lead to a proinflammatory response in the liver in the early phase after surgery, which changes to a more moderate immune response in the long-term. We suggest a preoperative risk stratification and postoperative surveillance depending on the histopathological findings.

Short-Term Changes in TNF-Alpha, IL-6 and Adiponectin Following Bariatric Surgery in Caucasian Obese Adults: An Observational Case-Control Study

Background and Objectives: Overweight and obesity are well-known conditions that negatively impact the health and lifestyle of an individual. Bariatric surgery is one of the most efficient weight loss techniques. Besides the main effect on the bodyweight, improvement in the levels of inflammatory biomarkers, such as interleukin 6 (IL-6), tumor necrosis factor alpha (TNFalfa), and others, has been observed. The purpose of this study was to establish the correlations between obesity-linked chronic systemic inflammation (estimated with inflammatory cytokine levels) and the weight loss process after metabolic surgery. Materials and Methods: An observational cohort study included two categories: the patients with obesity-bariatric group and the patients without obesity-control group. The study was performed between 1 February 2021 and 1 March 2023. Baseline characteristics, anthropometrics, biochemical assessment and inflammatory biomarkers were measured both before surgery and one year after the procedure, in the case of the bariatric group. The control group was assessed in the same period as the pre-surgery bariatric group. The bariatric group underwent two types of bariatric procedures: the majority underwent laparoscopic sleeve gastrectomy whereas a select few underwent one anastomosis laparoscopic gastric bypass. Results: We performed a prospective study comprising 55 Caucasian patients-from which 33 patients had morbid obesity, a mean age of 41.76 ± 10.78 and a mean BMI of 43.34± 7.51 kg/m2. The preoperative levels of IL-6 were positively correlated with waist circumference (r = 0.354, p = 0.043), weight (r = 0.549, p = 0.001) and BMI (r = 0.520, p = 0.002). After applying the Kruskal-Wallis test and Dunn's test, significant differences for IL-6 (p = 0.010) and adiponectin (p = 0.024) were obtained for values recorded pre- and post-surgery. No correlation was found between adiponectin, IL-6, TNF- α levels and anthropometric indices after surgery. Our study showed that bariatric surgery significantly changes the values of inflammatory cytokines one year after surgery. Nevertheless, we did not find significant correlations between the baseline values of these inflammatory markers and the weight loss process after surgery at a short-term (one-year) follow-up. Conclusions: Our study demonstrated that bariatric surgery significantly changes the level of inflammatory cytokines one year after operation. We demonstrate that preoperative levels of IL-6 are positively correlated with age, WC, and BMI.

Changes in Gut Microbial Composition and DNA Methylation in Obese Patients with NAFLD After Bariatric Surgery

This study investigates the effects of bariatric surgery on non-alcoholic fatty liver disease (NAFLD) by examining the interplay between gut microbiota, epigenetics, and metabolic health. A cohort of 22 patients undergoing sleeve gastrectomy (SG) was analyzed for changes in gut microbial composition and DNA methylation profiles before and six months after surgery. Correlations between gut microbial abundance and clinical markers at baseline revealed that certain genera were associated with worse metabolic health and liver markers. Following SG, significant improvements were observed in the clinical, anthropometric, and biochemical parameters of the NAFLD patients. Although alpha-diversity indices (i.e., Chao1, Simpson, Shannon) did not show significant changes, beta-diversity analysis revealed a slight shift in microbial composition (PERMANOVA, p = 0.036). Differential abundance analysis identified significant changes in specific bacterial taxa, including an increase in beneficial Lactobacillus species such as Lactobacillus crispatus and Lactobacillus iners and a decrease in harmful taxa like Erysipelotrichia. Additionally, DNA methylation analysis revealed 609 significant differentially methylated CpG sites between the baseline values and six months post-surgery, with notable enrichment in genes related to the autophagy pathway, such as IRS4 and ATG4B. The results highlight the individualized responses to bariatric surgery and underscore the potential for personalized treatment strategies. In conclusion, integrating gut microbiota and epigenetic factors into NAFLD management could enhance treatment outcomes, suggesting that future research should explore microbiome-targeted therapies and long-term follow-ups on liver health post-surgery.

Metabolic Surgery and Chronic Traumatic Encephalopathy: Perceptions of Former NFL Players

PURPOSE

Chronic traumatic encephalopathy (CTE) has been diagnosed in 91.7% of retired United States National Football League (NFL) players at postmortem. There is no treatment or cure for CTE. Most living former NFL athletes with probable CTE suffer from obesity and its comorbidities. Our previous reviews document the improvement in cognition following metabolic/bariatric surgery (MBS) (e.g., gastric bypass, sleeve gastrectomy). These operations might reduce microglial maladaptive states, thereby attenuating neurodegeneration and CTE-like neurocognitive impairment. The study evaluated former NFL players' views on metabolic surgery in relation to reduction of obesity and CTE risk.

MATERIALS AND METHODS

An online multiple-choice questionnaire (30 items, 125 response options, 10-min completion) developed in the Research Electronic Data Capture (REDCap) system was sent to 1,014 athletes screened in 2017-2022 by the Living Heart Foundation.

RESULTS

From 2/2022 to 7/2023, of 700 surveys opened, 72 (10.3%) of the retired players responded. Mean age was 61.6 ± 12.6 years; 45.0% had the disease of obesity with a mean BMI 35.5 ± 4.6 kg/m2. Thirty-three percent reported ≥ 2 obesity-related comorbidities; 40.3% memory-related TBI symptoms; 66.7% ≥ 1 cognitive symptom; 85.0% believed MBS was safe and effective but were unlikely to elect MBS for weight management. Yet, 57.0% of the entire cohort, and 68.8% of players with obesity were more likely to elect MBS if it could also reduce CTE risk.

CONCLUSIONS

Results of the study bode well for future research recruitment. Most surveyed retired NFL players with obesity believed MBS to be effective and would be more likely to undergo MBS if it also reduced CTE risk.

Stronger control of eating 3 months after sleeve gastrectomy predicts successful weight loss outcomes at one year

Background

Weight loss response to sleeve gastrectomy (SG) is variable and predicting the effectiveness of surgery is challenging and elusive. The aim of our study was to assess and quantify the association between eating control and weight loss outcomes and identify the control of eating (CoE) attributes during the early postoperative period that might predict good vs. poor response to SG at one year.

Methods

A prospective longitudinal cohort study using the Control of Eating Questionnaire (CoEQ) was designed as a series before and at 3-, 6-, and 12-months post-SG. Primary outcomes were changes in CoE attributes and percent of total weight loss (%TWL) 12-months post-surgery. Subjects were categorized based on %TWL as good (GR, ≥25 %) or poor responders (PR, <25 %). A receiver operating characteristic and logistic regression analyses were performed.

Results

We included 41 participants (80.5% females, 51.2% Hispanic, mean age 41.7±10.6, median baseline body mass index (BMI) 43.6 kg/m2 [range 35.2-66.3]) who completed the CoEQ at all four timepoints. The "Difficulty to control eating" score at 3 months revealed the highest area under the curve (AUC) (AUC 0.711; 95%CI 0.524-0.898; p=0.032). In a trade-off between a high Youden index and high sensitivity, the "Difficulty to control eating" score of 7 at 3 months was identified as the optimal cut-off for distinguishing between GRs and PRs. Score ≤7 at 3 months was strongly independently associated with a successful weight loss target of 25%TWL at one-year post-SG (Relative Risk 4.43; 95%CI 1.06-18.54; p=0.042).

Conclusion

"Difficulty to control eating" score at 3 months post-SG is an independent early predictor of optimal response (achieving a successful TWL target of ≥25 % at one-year post-SG). Our results support the utility of this easy-to-administer validated tool for predicting the effectiveness of SG and may assist in identifying individuals with suboptimal response early and helping them with interventions to attain optimal weight loss targets.

Long-term clinical outcomes of bariatric surgery in adults with severe obesity: A population-based retrospective cohort study

BACKGROUND

Bariatric surgery leads to sustained weight loss in a majority of recipients, and also reduces fasting insulin levels and markers of inflammation. We described the long-term associations between bariatric surgery and clinical outcomes including 30 morbidities.

METHODS

We did a retrospective population-based cohort study of 304,157 adults with severe obesity, living in Alberta, Canada; 6,212 of whom had bariatric surgery. We modelled adjusted time to mortality, hospitalization, surgery and the adjusted incidence/prevalence of 30 new or ongoing morbidities after 5 years of follow-up.

RESULTS

Over a median follow-up of 4.4 years (range 1 day-22.0 years), bariatric surgery was associated with increased risk of hospitalization (HR 1.46, 95% CI 1.41,1.51) and additional surgery (HR 1.42, 95% CI 1.32,1.52) but with a decreased risk of mortality (HR 0.76, 95% CI 0.64,0.91). After 5 years (median of 9.9 years), bariatric surgery was associated with a lower risk of severe chronic kidney disease (HR 0.45, 95% CI 0.27,0.75), coronary disease (HR 0.49, 95% CI 0.33,0.72), diabetes (HR 0.51, 95% CI 0.47,0.56), inflammatory bowel disease (HR 0.55, 95% CI 0.37,0.83), hypertension (HR 0.70, 95% CI 0.66,0.75), chronic pulmonary disease (HR 0.75, 95% CI 0.66,0.86), asthma (HR 0.79, 95% 0.65,0.96), cancer (HR 0.79, 95% CI 0.65,0.96), and chronic heart failure (HR 0.79, 95% CI 0.64,0.96). In contrast, after 5 years, bariatric surgery was associated with an increased risk of peptic ulcer (HR 1.99, 95% CI 1.32,3.01), alcohol misuse (HR 1.55, 95% CI 1.25,1.94), frailty (HR 1.28, 95% 1.11,1.46), severe constipation (HR 1.26, 95% CI 1.07,1.49), sleep disturbance (HR 1.21, 95% CI 1.08,1.35), depression (HR 1.18, 95% CI 1.10,1.27), and chronic pain (HR 1.12, 95% CI 1.04,1.20).

INTERPRETATION

Bariatric surgery was associated with lower risks of death and certain morbidities. However, bariatric surgery was also associated with increased risk of hospitalization and additional surgery, as well as certain other morbidities. Since values and preferences for these various benefits and harms may differ between individuals, this suggests that comprehensive counselling should be offered to patients considering bariatric surgery.

Preoperative weight loss interventions before total hip and knee arthroplasty: a systematic review of randomized controlled trials

BACKGROUND

The high co-prevalence of obesity and end-stage osteoarthritis requiring arthroplasty, with the former being a risk factor for complications during arthroplasty, has led to increasing interest in employing preoperative weight loss interventions such as bariatric surgery and diet modification. However, the current evidence is conflicting, and this study aimed to investigate the effect of weight loss intervention before arthroplasty in prospective randomized controlled trials.

METHODS

Four electronic databases (MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials) were searched for prospective randomized controlled trials that compared weight loss interventions with usual care from inception to October 2023 by following the PRISMA guidelines. The Cochrane risk of bias tool and GRADE framework were used to assess the quality of the studies. Meta-analyses were performed when sufficient data were available from 2 or more studies.

RESULTS

Three randomized controlled trials involving 198 patients were identified. Two studies employed diet modification, and one study utilized bariatric surgery. All three studies reported significant reductions in body weight and body mass index (BMI), and intervention groups had fewer postoperative complications. There was no difference in the length of stay between the intervention group and the control group. Variable patient-reported outcome measures were used by different research groups.

CONCLUSION

Weight loss intervention can achieve significant reductions in body weight and body mass index before arthroplasty, with fewer postoperative complications reported. Further studies with different populations could confirm the effect of these interventions among populations with different obesity characteristics.

Effect of Sleeve Gastrectomy Versus One Anastomosis Gastric Bypass on Postoperative Renal Function and the Urinary Monocyte Chemoattractant Protein-1 (MCP-1) Level

INTRODUCTION

Bariatric surgery has been the most effective treatment modality for morbid obesity that reduces associated comorbidities and improves quality of life. This study aims at evaluating and comparing the impact of two types of bariatric surgery-laparoscopic sleeve gastrectomy (LSG) and one anastomosis gastric bypass (OAGB)-on renal functions and urinary monocyte chemoattractant protein-1 (MPC-1) levels in morbidly obese patients 3 months after surgery.

METHODS

This is a prospective study of 40 morbidly obese patients who underwent bariatric surgery. Two types of bariatric surgery were done-laparoscopic sleeve gastrectomy (LSG) (26 patients) and laparoscopic one anastomosis gastric bypass (OAGB) (14 patients). The outcomes of the two procedures were compared in terms of renal function parameters and the level of urinary MCP-1.

RESULTS

There were no statistically significant differences in the mean postoperative urinary MCP-1 (73.53 ± 21.25, 75.43 ± 26.17, P > 0.5), microalbuminuria (8.83 ± 6.26, 10.02 ± 8.6, P > 0.05), urinary creatinine (109.21 ± 43.22, 99.19 ± 48.65, P > 0.05), MCP1/Cr ratio (0.78 ± 0.36, 1.01 ± 0.70, P > 0.05), eGFR (100.32 ± 9.54, 104.39 ± 9.54, P > 0.05) in the cases who had either LSG operation or OAGB operation.

CONCLUSION

Bariatric surgery improves all indicators of kidney malfunction and reduces the level of urinary MCP-1. Both laparoscopic sleeve gastrectomy (LSG) and laparoscopic one anastomosis gastric bypass (OAGB) cause similar improvement of the renal function and reduction of urinary MCP-1 level.

Bariatric surgery decreases the capacity of plasma from obese asthmatic subjects to augment airway epithelial cell proinflammatory cytokine production

Obesity is a risk factor for asthma. Individuals with asthma and obesity often have poor asthma control and do not respond as well to therapies such as inhaled corticosteroids and long-acting bronchodilators. Weight loss improves asthma control, with a 5%-10% loss in body mass necessary and sufficient to lead to clinically relevant improvements. Preclinical studies have demonstrated the pathogenic contribution of adipocytes from obese mice to the augmented production of proinflammatory cytokines from airway epithelial cells and the salutary effects of diet-induced weight loss to decrease these consequences. However, the effects of adipocyte-derived products on airway epithelial function in human obesity remain incompletely understood. We utilized samples collected from a 12-mo longitudinal study of subjects with obesity undergoing weight loss (bariatric) surgery including controls without asthma and subjects with allergic and nonallergic obese asthma. Visceral adipose tissue (VAT) samples were collected during bariatric surgery and from recruited normal weight controls without asthma undergoing elective abdominal surgery. Human bronchial epithelial (HBEC3-KT) cells were exposed to plasma or conditioned media from cultured VAT adipocytes with or without agonists. Human bronchial smooth muscle (HBSM) cells were similarly exposed to adipocyte-conditioned media. Proinflammatory cytokines were augmented in supernatants from HBEC3-KT cells exposed to plasma as compared with subsequent visits. Whereas exposure to obese adipocyte-conditioned media induced proinflammatory responses, there were no differences between groups in both HBEC3-KT and HBSM cells. These data show that bariatric surgery and subsequent weight loss beneficially change the circulating factors that augment human airway epithelial and bronchial smooth muscle cell proinflammatory responses.NEW & NOTEWORTHY This longitudinal study following subjects with asthma and obesity reveals that weight loss following bariatric surgery decreases the capacity for plasma to augment proinflammatory cytokine secretion by human bronchial epithelial cells, implicating that circulating but not adipocyte-derived factors are important modulators in obese asthma.

Variation of modulation and expression of biomarkers associated with inflammation in bariatric surgery patients: A systematic review and meta-analysis

BACKGROUND

Bariatric surgery is an effective intervention that causes a series of metabolic changes related to inflammatory processes; however, the variation of biomarkers related to these processes is not entirely understood. Our objective was to investigate the variation of modulation and expression of biomarkers associated with inflammation in patients who underwent bariatric surgery.

METHODS

We searched the MEDLINE (via PubMed), EMBASE (via Elsevier), Cochrane Central Register of Controlled Trials, Latin American and Caribbean Literature on Health Sciences (via virtual health library), Cumulative Index to Nursing and Allied Health Literature (via EBSCO), Web of Science core collection, and Scopus (via Elsevier) databases, and the gray literature was examined from inception to January 2022. Three pairs of reviewers performed data screening, extraction, and quality assessment independently. Meta-analysis with random effects models was used for general, subgroup, and sensitivity analyses. The I2 statistic was used to assess heterogeneity between studies.

RESULTS

In total, 96 articles were included in this systematic review; of these, 87 studies met the criteria for the meta-analysis, involving 3,533 participants. Five biomarkers were included in the meta-analysis (tumor necrosis factor alpha; interleukin 6; leptin; interleukin 1 beta, and lipopolysaccharides). Only leptin showed a significant decrease in the first month after surgery (mean difference -20.71; [95% confidence interval: -28.10 to -13.32, P < .0001; I2 = 66.7%), with moderate heterogeneity. The 12 months after surgery showed a significant decrease in tumor necrosis factor alpha (mean difference -0.89; [95% confidence interval: -1.37 to -0.42], P = .0002; I2 = 94.7%), interleukin 6 (mean difference -1.62; [95% confidence interval: -1.95 to -1.29], P < .0001; I2 = 94.9%), leptin (mean difference -28.63; [95% confidence interval: -34.02 to -23.25], P < .0001; I2 = 92.7%), and interleukin 1 beta (mean difference -2.46; [95% confidence interval: -4.23 to -0.68], P = .006; I2 = 98.3%), all with high heterogeneity. The type of surgery did not show significant differences for the biomarkers at the first month and 12 months, and the results have not changed with high-quality studies. In the 12-month measurement, variations in tumor necrosis factor alpha and leptin were associated with body mass index.

CONCLUSION

The findings of this meta-analysis suggest that Roux-en-Y gastric bypass and sleeve gastrectomy bariatric surgeries are associated with a significant reduction in leptin at 1 month after bariatric surgical intervention and tumor necrosis factor alpha, leptin, and interleukin 1 beta after 12 months.

Effect of bariatric surgery procedures on serum cytokine and Nesfatin-1 levels

BACKGROUND

and Purpose: Obesity is known to cause chronic inflammation. We aimed to evaluate the changes in Nesfatin-1 and serum cytokine levels of patients who underwent sleeve gastrectomy or gastric bypass surgery.

METHODS

A total of 30 patients with BMI>35 and undergoing bariatric surgery were divided in two group, sleeve gastrectomy (SG) (group-1), Roux-en-Y gastric bypass (RYGB) (group-2). Demographic data, weight, BMI, AST, ALT, blood glucose, CRP values, and IL-1β, IFN-α, IFN-γ, TNF-α, MCP-1, IL-6, IL-8, IL-10, IL-12p70, IL-17A, IL-18, IL-23, IL-33 cytokine, and Nesfatin-1 values were noted at the time of hospitalization and in the 6th month postoperative follow-up.

RESULTS

The mean age of the patients was 37.56 ± 11.73 years, and there were 16 females and 14 males in the study. Body weight and excess body weight change were slightly higher in RYGB patients than in SG patients. In RYGB and SG patients, a significant decrease was found in glucose, AST, ALT, CRP, IL-6, IL-10, and IL-18 values compared to the preoperative period, and serum Nesfatin-1 levels were significantly increased in RYGB patients and not significantly in SG patients. There were also significant decreases in IL-1β levels in RYGB patients. On the other hand, a decrease in cytokines was observed in both surgical methods, except for IL-17A, although it was not significant.

CONCLUSION

The present study showed that there is also a regression in inflammation, which can be associated with NLRP3 inflammasome, due to weight loss after bariatric surgery, more specifically in RYGB.

Impact of intestinal microenvironments in obesity and bariatric surgery on shaping macrophages

Obesity is associated with alterations in tissue composition, systemic cellular metabolism, and low-grade chronic inflammation. Macrophages are heterogenous innate immune cells ubiquitously localized throughout the body and are key components of tissue homeostasis, inflammation, wound healing, and various disease states. Macrophages are highly plastic and can switch their phenotypic polarization and change function in response to their local environments. Here, we discuss how obesity alters the intestinal microenvironment and potential key factors that can influence intestinal macrophages as well as macrophages in other organs, including adipose tissue and hematopoietic organs. As bariatric surgery can induce metabolic adaptation systemically, we discuss the potential mechanisms through which bariatric surgery reshapes macrophages in obesity.

Obesity and recurrent miscarriage: The interconnections between adipose tissue and the immune system

Currently, obesity is considered a global public health problem. It is the main risk factor for noncommunicable diseases and reproductive complications, such as recurrent miscarriage (RM). RM affects approximately 1% of couples of reproductive age, and recent studies suggest that its prevalence is increasing. Immunological abnormalities may be responsible for a significant number of cases of unexplained RM. Obesity is recognized as a chronic low-grade inflammatory condition. The accumulation of fat in obese adipose tissue promotes changes in the local and systemic immune response. Adipokines, exosomes, micro-RNAs, lipids, and other factors released or secreted by adipose tissue are responsible for the interconnection between obesity and the immune system. Obesity-induced dysregulation of the innate and acquired immune response is also involved in the immunopathology of pregnancy loss in patients with unexplained RM. Therefore, understanding the communication pathways between maternal adipose tissue and the immune response in women living with obesity and RM is an important objective. Thus, diagnostic tools and new immunomodulatory therapies may be proposed for the management of patients with concurrent obesity and RM.

Serum IL-23 significantly decreased in obese patients with psoriatic arthritis six months after a structured weight loss intervention

INTRODUCTION

Patients with psoriatic arthritis (PsA) are frequently obese. We have previously shown decreased disease activity in patients with PsA with a body mass index (BMI) ≥ 33 kg/m² following weight loss treatment with Very Low Energy Diet (VLED), resulting in a median weight loss of 18.6% at six months (M6) after baseline (BL). In this study we assessed the effects of VLED on cytokines and adipokines at M6 in the same patients with PsA and controls (matched on sex, age and weight).

METHODS

VLED (640 kcal/day) during 12 or 16 weeks, depending on BL BMI < 40 or ≥ 40 kg/m², was taken and followed by an energy-restricted diet. Cytokines and adipokines were measured with Magnetic Luminex Assays at BL and M6.

RESULTS

Serum interleukin (IL)-23, (median (interquartile range) 0.40 (0.17-0.54) ng/mL vs. 0.18 (0.10-0.30) ng/mL, p < 0.001) and leptin (26.28 (14.35-48.73) ng/mL vs. 9.25 (4.40-16.24) ng/mL, p < 0.001) was significantly decreased in patients with PsA. Serum total (tot)-adiponectin and high molecular weight (HMW) adiponectin increased significantly. Similar findings were found in controls. Also, in patients with PsA, ∆BMI was positively correlated with ∆IL-23 (r_S = 0.671, p < 0.001). In addition, significant positive correlations were found between ΔBMI and ΔDisease Activity Score (DAS28CRP), ΔCRP, Δtumor necrosis factor (TNF)-α, ΔIL-13, ∆IL-17 and Δleptin, and negative correlations between ΔBMI and Δtot-adiponectin.

CONCLUSIONS

Weight loss was associated with decreased levels of leptin and cytokines, in particular IL-23. These findings may partly explain the anti-inflammatory effect of weight reduction in PsA.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02917434, registered on September 21, 2016, retrospectively registered.

Roux-en-Y Gastric Bypass Improves Adiponectin to Leptin Ratio and Inflammatory Profile in Severely Obese Women with and without Metabolic Syndrome: A Randomized Controlled Trial

Obesity is a troubling public health problem as it increases risks of sleep disorders, respiratory complications, systemic arterial hypertension, cardiovascular diseases, type 2 diabetes mellitus, and metabolic syndrome (MetS). As a measure to counteract comorbidities associated with severe obesity, bariatric surgery stands out. This study aimed to investigate the adiponectin/leptin ratio in women with severe obesity with and without MetS who had undergone Roux-en-Y gastric bypass (RYGB) and to characterize the biochemical, glucose, and inflammatory parameters of blood in women with severe obesity before and after RYGB. Were enrolled females with severe obesity undergoing RYGP with MetS (n = 11) and without (n = 39). Anthropometric data and circulating levels of glucose, total cholesterol, high-density lipoprotein (HDL), non-HDL total cholesterol, low-density lipoprotein (LDL), adiponectin, and leptin were assessed before and 6 months after RYGB. Significant reductions in weight, body mass index, and glucose, total cholesterol, LDL, and leptin were observed after surgery, with higher levels of HDL, adiponectin, and adiponectin/leptin ratio being observed after surgery compared to the preoperative values of those. This study demonstrated that weight loss induced by RYGB in patients with severe obesity with or without MetS improved biochemical and systemic inflammatory parameters, particularly the adiponectin/leptin ratio.

Distinct adaptations of endocrine and cognitive functions may contribute to high variability in long-term weight loss outcome after bariatric surgery

BACKGROUND

Bariatric surgery has been widely recognized as the most efficient long-term treatment method in severe obesity, yet therapy success shows considerable interindividual variability. Postoperative metabolic adaptations, including improved gut hormone secretion (GLP-1, PYY and ghrelin), and restored executive function may play an explanatory role in weight loss, yet causes for poor success in individual patients remain unknown. This study investigates gut-hormonal and cognitive characteristics in extreme weight loss responders to bariatric surgery.

METHODS

Patients (n=47) with high or low excessive weight loss (EWL) at least 2 years after Roux-en-Y-gastric bypass or sleeve gastrectomy were allocated into good responders (GR, EWL 82.4 ± 11.6%) and poor responders (PR, EWL 24.0 ± SD 12.8%) to study differences in postprandial secretion of GLP-1, PYY, ghrelin and in working memory (WM).

RESULTS

Mean BMI was 47.1 ± 6.2 kg/m² in PR (n=21) and 28.9 ± 3.1 kg/m² in GR (n=26, p < 0.001). Fasted GLP-1 and PYY were comparable for GR and PR (p > 0.2) and increased strongly after a standardized test meal (300 kcal liquid meal) with a peak at 15 to 30 minutes. The increase was stronger in GR compared to PR (GLP-1, PYY: Time x Group p < 0.05). Plasma ghrelin levels already differed between groups at fasted state, showing significantly higher levels for GR (p < 0.05). Postprandially, ghrelin secretion was suppressed in both groups, but suppression was higher in GR (Time x Group p < 0.05). GR showed significantly higher WM scores than PR (p < 0.05). Postprandial ghrelin (iAUC), but not GLP-1 or PYY plasma levels, significantly mediated the relationship between EWL and a WM subscore (IS score, CI = 0.07 - 1.68), but not WM main score (MIS score, CI = -0.07 - 1.54), in mediation analyses.

CONCLUSION

Excess weight loss success after bariatric surgical procedures is associated with distinct profiles of gut-hormones at fasted and postprandial state, and differences in working memory. Better working memory performance in GR might be mediated by higher postprandial reduction in ghrelin plasma levels. Future studies need to integrate longitudinal data, larger samples and more sensitive cognitive tests.

Molecular Mechanisms of Western Diet-Induced Obesity and Obesity-Related Carcinogenesis-A Narrative Review

The present study aims to provide a narrative review of the molecular mechanisms of Western diet-induced obesity and obesity-related carcinogenesis. A literature search of the Cochrane Library, Embase and Pubmed databases, Google Scholar and the grey literature was conducted. Most of the molecular mechanisms that induce obesity are also involved in the twelve Hallmarks of Cancer, with the fundamental process being the consumption of a highly processed, energy-dense diet and the deposition of fat in white adipose tissue and the liver. The generation of crown-like structures, with macrophages surrounding senescent or necrotic adipocytes or hepatocytes, leads to a perpetual state of chronic inflammation, oxidative stress, hyperinsulinaemia, aromatase activity, activation of oncogenic pathways and loss of normal homeostasis. Metabolic reprogramming, epithelial mesenchymal transition, HIF-1α signalling, angiogenesis and loss of normal host immune-surveillance are particularly important. Obesity-associated carcinogenesis is closely related to metabolic syndrome, hypoxia, visceral adipose tissue dysfunction, oestrogen synthesis and detrimental cytokine, adipokine and exosomal miRNA release. This is particularly important in the pathogenesis of oestrogen-sensitive cancers, including breast, endometrial, ovarian and thyroid cancer, but also 'non-hormonal' obesity-associated cancers such as cardio-oesophageal, colorectal, renal, pancreatic, gallbladder and hepatocellular adenocarcinoma. Effective weight loss interventions may improve the future incidence of overall and obesity-associated cancer.

Inflammatory Cytokines, Redox Status, and Cardiovascular Diseases Risk after Weight Loss via Bariatric Surgery and Lifestyle Intervention

Background and Objectives: Obesity is a chronic inflammatory condition and is considered a major risk factor for cardiovascular disease (CVD). The effects of obesity management via sleeve gastrectomy (SG) and lifestyle intervention (LS) on inflammatory cytokines, redox status, and CVD risk were studied in this work. Materials and Methods: A total of 92 participants (18 to 60 years old) with obesity (BMI ≥ 35 kg/m2 were divided into two groups: the bariatric surgery (BS) group (n = 30), and the LS group (n = 62). According to the achievement of 7% weight loss after 6 months, the participants were allocated to either the BS group, the weight loss (WL) group, or the weight resistance (WR) group. Assessments were performed for body composition (by bioelectric impedance), inflammatory markers (by ELISA kits), oxidative stress (OS), antioxidants (by spectrophotometry), and CVD risk (by the Framingham risk score (FRS) and lifetime atherosclerotic cardiovascular disease risk (ASCVD)). Measurements were taken before and after six months of either SG or LS (500 kcal deficit balanced diet, physical activity, and behavioral modification). Results: At the final assessment, only 18 participants in the BS group, 14 participants in the WL group, and 24 participants in the WR group remained. The loss in fat mass (FM) and weight loss were greatest in the BS group (p < 0.0001). Levels of IL-6, TNF-a, MCP-1, CRP, and OS indicators were significantly reduced in the BS and WL groups. The WR group had significant change only in MCP-1 and CRP. Significant reductions in the CVD risk in the WL and BS groups were detected only when using FRS rather than ASCVD. The FM loss correlated inversely with FRS-BMI and ASCVD in the BS group, whereas in the WL group, FM loss correlated only with ASCVD. Conclusions: BS produced superior weight and fat mass loss. However, both BS and LS produced a similar reduction in the inflammatory cytokines, relief of OS indicators, and enhancement of antioxidant capacity, and consequently reduced the CVD risk.

Effects of Roux-en-Y gastric bypass on the metabolic profile and systemic inflammatory status of women with metabolic syndrome: randomized controlled clinical trial

BACKGROUND

Obesity remains a public health problem worldwide. The high prevalence of this condition in the population raises further concerns, considering that comorbidities are often associated with obesity. Among the comorbidities closely associated with obesity, metabolic syndrome (MS) is particularly important, which potentially increases the risk of manifestation of other disorders, such as the prothrombotic and systemic pro-inflammatory states.

METHODS

A randomized, controlled clinical trial was performed involving female patients (n = 32) aged between 18 and 65 years, with a clinical diagnosis of MS, with severe obesity undergoing Roux-en-Y gastric bypass (RYGB). The study design followed the Consolidated Standards of Reporting Trials statement (CONSORT). Lipid profile, blood glucose and adipokines (adiponectin, leptin, and resistin) and (cytokines IL-1β, IL-6, IL-17, IL-23, and TNF-α) in blood plasma samples were evaluated before and six months after RYGB.

RESULTS

Patients undergoing RYGB (BSG) showed a significant improvement from preoperative grade III obesity to postoperative grade I obesity. The results showed that while HDL levels increased, the other parameters showed a significant reduction in their postoperative values when compared not only to the values observed before surgery in the BSG group, but also to the values obtained in the control group (CG). As for systemic inflammatory markers adiponectin, leptin, resistin, IL-1β, IL-6, IL-17, IL-23 and TNF- α it was observed that the levels of resistin and IL-17 in the second evaluation increased significantly when compared to the levels observed in the first evaluation in the CG. In the BSG group, while the levels of adiponectin increased, the levels of the other markers showed significant reductions in the postoperative period, in relation to the respective preoperative levels. The analysis of Spearman's correlation coefficient showed a significant positive correlation between IL-17 and IL-23 in the preoperative period, significant positive correlations between TNF-α and IL-6, TNF-α and IL-17, IL-6 and IL-17, and IL-17 and IL-23 were observed postoperatively.

CONCLUSIONS

According to our results, the reduction of anthropometric measurements induced by RYGB, significantly improves not only the plasma biochemical parameters (lipid profile and glycemia), but also the systemic inflammatory status of severely obese patients with MS. Trials registration NCT02409160.

Regulation of body weight: Lessons learned from bariatric surgery

BACKGROUND

Bariatric or weight loss surgery is currently the most effective treatment for obesity and metabolic disease. Unlike dieting and pharmacology, its beneficial effects are sustained over decades in most patients, and mortality is among the lowest for major surgery. Because there are not nearly enough surgeons to implement bariatric surgery on a global scale, intensive research efforts have begun to identify its mechanisms of action on a molecular level in order to replace surgery with targeted behavioral or pharmacological treatments. To date, however, there is no consensus as to the critical mechanisms involved.

SCOPE OF REVIEW

The purpose of this non-systematic review is to evaluate the existing evidence for specific molecular and inter-organ signaling pathways that play major roles in bariatric surgery-induced weight loss and metabolic benefits, with a focus on Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG), in both humans and rodents.

MAJOR CONCLUSIONS

Gut-brain communication and its brain targets of food intake control and energy balance regulation are complex and redundant. Although the relatively young science of bariatric surgery has generated a number of hypotheses, no clear and unique mechanism has yet emerged. It seems increasingly likely that the broad physiological and behavioral effects produced by bariatric surgery do not involve a single mechanism, but rather multiple signaling pathways. Besides a need to improve and better validate surgeries in animals, advanced techniques, including inducible, tissue-specific knockout models, and the use of humanized physiological traits will be necessary. State-of-the-art genetically-guided neural identification techniques should be used to more selectively manipulate function-specific pathways.

The Effect of Bariatric Surgery on Circulating Levels of Monocyte Chemoattractant Protein-1: A Systematic Review and Meta-Analysis

Background: MCP-1 (monocyte chemoattractant protein) plays an important role in early phases of atherogenesis as well as in plaque destabilization, which causes cardiovascular events to play an important role in low-grade inflammation. Obesity, particularly extreme obesity, is a pivotal risk factor for atherosclerosis and many other diseases. In the early stages, bariatric surgery might stop or slow atherogenesis by suppressing inflammation, but also in later stages, preventing plaque destabilization. The aim of this meta-analysis was to provide an answer as to whether bariatric surgery has a significant effect on circulating MCP-1 level or not. Methods: A systematic literature search in PubMed, Scopus, Embase, and Web of Science was performed from inception to 1 January 2022. Meta-analysis was performed using Comprehensive Meta-Analysis (CMA) V2 software. In order to heterogeneity compensation of studies in terms of study design and treatment duration, the characteristics of the studied populations random-effects model and the generic inverse variance weighting method were used. To investigate the relationship with the estimated effect size, a random-effect meta-regression model was used. To assess the exitance of publication bias in the meta-analysis, the funnel plot, Begg's rank correlation, and Egger's weighted regression tests were used. Results: Meta-analysis of 25 studies with 927 subjects included demonstrated a significant decrease of MCP-1 concentration after bariatric surgery. The data of meta-regression did not indicate any association between the alterations in body mass index (BMI) and absolute difference in MCP-1 levels, but a linear relationship between the changes in MCP-1 and length of follow-up was proven. Conclusions: Bariatric surgery significantly decreases MCP-1 concentration, but there was no association between the changes in BMI and absolute difference in MCP-1 levels before and after the surgery.

Periodontal Therapy in Bariatric Surgery Patients with Periodontitis: Randomized Control Clinical Trial

Background: Bariatric surgery (BS) patients may experience the progression of periodontitis during recovery. We aimed to determine whether non-surgical periodontal therapy before BS improves the periodontal and systemic health parameters after the surgery. Methods: BS candidates with periodontitis were randomized into the test (TG) and control group (CG). One month before BS (pre-BS), patients in the TG (n = 15) received non-surgical periodontal therapy, while patients in the CG (n = 15) received only mechanical plaque removal. Patients were re-examined 3 and 6 months after BS. Differences between the TG and CG in clinical periodontal parameters, systemic health-related serum biomarkers, parameters of obesity, and prevalence of obesity-related diseases were evaluated. Results: From the 30 included patients, 26 were re-examined at 3 months and 20 patients at 6 months. Periodontal parameters bleeding on probing (p = 0.015), periodontal pocket dept (PPD, p = 0.0015), % PPD > 4 mm (p < 0.001), and full-mouth plaque levels (p = 0.002) were lower in the TG than in the CG at 6 months after BS. There is a general improvement in systemic health after BS without significant differences (p > 0.05) between the TG and CG at the 6-month follow-up. The TG shows a tendency for improvement in metabolic syndrome components at the 6-month follow-up compared to pre-BS (p < 0.05). Conclusions: Non-surgical periodontal therapy in periodontitis patients before the BS may improve periodontal health 3 and 6 months after the surgery. The possible benefits of periodontal therapy on the overall health of BS patients should be further explored.

Netrin-1 Promotes Visceral Adipose Tissue Inflammation in Obesity and Is Associated with Insulin Resistance

Netrin (NTN)-1 exhibits pro- and anti-inflammatory roles in different settings, playing important roles in the obesity-associated low-grade chronic inflammation. We aimed to determine the impact of NTN-1 on obesity and obesity-associated type 2 diabetes, as well as its role in visceral adipose tissue (VAT) inflammation. A total of 91 subjects were enrolled in this case-control study. Circulating levels of NTN-1 and its receptor neogenin (NEO)-1 were determined before and after weight loss achieved by caloric restriction and bariatric surgery. mRNA levels of NTN1 and NEO1 were assessed in human VAT, liver, and peripheral blood mononuclear cells. In vitro studies in human visceral adipocytes and human monocytic leukemia cells (THP-1)-derived macrophages were performed to analyze the impact of inflammation-related mediators on the gene expression levels of NTN1 and its receptor NEO1 as well as the effect of NTN-1 on inflammation. Increased (p < 0.001) circulating concentrations of NTN-1 in obesity decreased (p < 0.05) after diet-induced weight loss being also associated with a reduction in glucose (p < 0.01) and insulin levels (p < 0.05). Gene expression levels of NTN1 and NEO1 were upregulated (p < 0.05) in the VAT from patients with obesity with the highest expression in the stromovascular fraction cells compared with mature adipocytes (p < 0.01). NTN1 expression levels were enhanced (p < 0.01) under hypoxia and by inflammatory factors in both adipocytes and macrophages. Adipocyte-conditioned media strongly upregulated (p < 0.001) the mRNA levels of NTN1 in macrophages. The treatment of adipocytes with NTN-1 promoted the upregulation (p < 0.05) of pro-inflammatory and chemotactic molecules as well as its receptor NEO1. Collectively, these findings suggest that NTN-1 regulates VAT chronic inflammation and insulin resistance in obesity.

Demographic, behavioral, dietary, and clinical predictors of high-sensitivity C-reactive protein: The National Health and Nutrition Examination Surveys (NHANES)

Aims

High-sensitivity C-reactive protein (hs-CRP), a marker of inflammation, is associated with atherosclerosis, and recent studies indicate that therapies targeting inflammation are associated with reductions in cardiovascular risk. However, factors predictive of elevated hs-CRP in the general population have not been elucidated.

Methods

In this cross-sectional study, multivariable logistic regression analysis was used to identify independent predictors of elevated hs-CRP (≥3 mg/L) utilizing the National Health and Nutrition Examination Survey (NHANES) 2015-2016 cycle. The model was verified using the independent NHANES 2017-2018 cycle. Candidate variables comprised demographic, behavioral, dietary, and clinical factors. The study included 5412 adults from the 2015-2016 cohort and 5856 adults from the 2017-2018 cohort.

Results

Significant independent predictors of elevated hs-CRP included: older age (OR 1.09 per decade; 95 % CI 1.03-1.14; P = 0.024), female sex (OR 1.57; 95 % CI 1.36-1.80; P = 0.003), Black vs White race (OR 1.31; 95 % CI 1.10-1.56; P = 0.037), increased BMI (OR 1.12 per kg/m2; 95 % CI 1.10-1.14; P < 0.001), elevated white blood cell count (OR 1.21 per 1000 white blood cells/μL; 95 % CI 1.15-1.28; P = 0.002), and self-reported poor vs excellent health (OR 1.73; 95 % CI 1.04-2.22; P = 0.012). The model had excellent discrimination with a c-statistic of 0.77 in the 2015-2016 cycle and 0.76 in the 2017-2018 cycle.

Conclusion

Older age, female sex, Black race, increased BMI, higher white blood cell count, and self-reported poor health were independent predictors of elevated hs-CRP levels. Additional studies are needed to determine if behavioral modifications can lower hs-CRP and whether this translates to reduced risk for cardiovascular disease and other conditions associated with chronic inflammation.

Lipid Peroxidation in Obesity: Can Bariatric Surgery Help?

Obesity and chronic oxidative stress, often being associated with each other in a vicious circle, are important factors of chronic diseases. Although it was usually considered to accompany aging and wealth, global trends show the increase in obesity among children even in Third World countries. Being manifested by an imbalance between energy consumption and food intake, obesity is characterized by an excessive or abnormal fat accumulation, impaired redox homeostasis and metabolic changes often associated with the self-catalyzed lipid peroxidation generating 4-hydroxynonenal, pluripotent bioactive peroxidation product of polyunsaturated fatty acids. Conservative methods targeting obesity produced only modest and transient results in the treatment of morbid obesity. Therefore, in recent years, surgery, primarily bariatric, became an attractive treatment for morbid obesity. Since adipose tissue is well known as a stress organ with pronounced endocrine functions, surgery results in redox balance and metabolic improvement of the entire organism. The source of bioactive lipids and lipid-soluble antioxidants, and the complex pathophysiology of lipid peroxidation should thus be considered from the aspects of personalized and integrative biomedicine to treat obesity in an appropriate way.

Macrophages, Low-Grade Inflammation, Insulin Resistance and Hyperinsulinemia: A Mutual Ambiguous Relationship in the Development of Metabolic Diseases

Metabolic derangement with poor glycemic control accompanying overweight and obesity is associated with chronic low-grade inflammation and hyperinsulinemia. Macrophages, which present a very heterogeneous population of cells, play a key role in the maintenance of normal tissue homeostasis, but functional alterations in the resident macrophage pool as well as newly recruited monocyte-derived macrophages are important drivers in the development of low-grade inflammation. While metabolic dysfunction, insulin resistance and tissue damage may trigger or advance pro-inflammatory responses in macrophages, the inflammation itself contributes to the development of insulin resistance and the resulting hyperinsulinemia. Macrophages express insulin receptors whose downstream signaling networks share a number of knots with the signaling pathways of pattern recognition and cytokine receptors, which shape macrophage polarity. The shared knots allow insulin to enhance or attenuate both pro-inflammatory and anti-inflammatory macrophage responses. This supposedly physiological function may be impaired by hyperinsulinemia or insulin resistance in macrophages. This review discusses the mutual ambiguous relationship of low-grade inflammation, insulin resistance, hyperinsulinemia and the insulin-dependent modulation of macrophage activity with a focus on adipose tissue and liver.

Effects of obesity on neuroinflammatory and neurochemical parameters in an animal model of reserpine-induced Parkinson's disease

Obesity is associated with low-grade chronic inflammation and oxidative stress, affecting the brain's reward system by decreasing dopaminergic neurotransmission. It is known that dopaminergic neurotransmission is also reduced in Parkinson's disease (PD), and high adiposity is considered a risk factor for the development of several neurodegenerative diseases, including PD. This study aimed to assess the effects of obesity on neuroinflammatory and neurochemical parameters in an animal model of reserpine-induced PD. The obese group showed increased inflammation and oxidative damage as well as inhibition of mitochondrial respiratory chain complexes I and II and DNA damage in the evaluated structures. The PD group did not show inflammation or mitochondrial dysfunction but exhibited oxidative damage in the hippocampus. The combination group (obesity + PD) showed reduced inflammation and oxidative stress and increased activity of complexes I and II of the mitochondrial respiratory chain in most of the analyzed structures. On the other hand, obesity + PD caused oxidative damage to proteins in the liver, prefrontal cortex, striatum, and cerebral cortex and oxidative stress in the hypothalamus, resulting in reduced catalase activity. Furthermore, the combination group showed DNA damage in blood, liver, and cerebral cortex. In conclusion, it was observed that the association of obesity and PD did not increase inflammation, oxidative stress, or mitochondrial dysfunction in most of the evaluated structures but increased oxidative damage and induced mechanisms that led to DNA damage in peripheral tissues and brain structures.

Association of irisin levels with cardiac magnetic resonance, inflammatory, and biochemical parameters in patients with chronic heart failure versus controls

BACKGROUND AND AIMS

Chronic heart failure (CHF) represents a significant cause of morbidity and mortality globally. Metabolic maladaptation has proven to be critical in the progression of this condition. Preclinical studies have shown that irisin, an adipomyokine involved in metabolic regulations, can induce positive cardioprotective effects by improving cardiac remodeling, cardiomyocyte viability, calcium delivery, and reducing inflammatory mediators. However, data on clinical studies identifying the associations between irisin levels and functional imaging parameters are scarce in CHF patients. The objective of this study was to determine the association of irisin levels with cardiac imaging measurements through cardiac magnetic resonance, inflammatory markers, and biochemical parameters in patients with CHF compared with control subjects.

METHODS AND RESULTS

Thirty-two subjects diagnosed with CHF and thirty-two healthy controls were evaluated in a cross-sectional study. Serum irisin levels were significantly lower in patients with CHF than in controls. This is the first study to report a significant positive correlation between irisin levels and cardiac magnetic resonance parameters such as left ventricular ejection fraction, fraction shortening, and global radial strain. A negative correlation was demonstrated between irisin levels and brain natriuretic peptide, insulin levels, and Homeostatic model assessment for insulin resistance index. We did not observe significant correlations between irisin levels and inflammatory cytokines.

CONCLUSIONS

Given the importance of fraction shortening and global radial strain as accurate markers of ventricular wall motion, these results support the hypothesis that irisin may play an essential role in maintaining an adequate myocardial wall architecture, deformation, and thickness.

Increased inflammatory low-density neutrophils in severe obesity and effect of bariatric surgery: Results from case-control and prospective cohort studies

BACKGROUND

Low-density neutrophils (LDN) are increased in several inflammatory diseases and may also play a role in the low-grade chronic inflammation associated with obesity. Here we explored their role in obesity, determined their gene signatures, and assessed the effect of bariatric surgery.

METHODS

We compared the number, function, and gene expression profiles of circulating LDN in morbidly obese patients (MOP, n=27; body mass index (BMI) > 40 Kg/m2) and normal-weight controls (NWC, n=20; BMI < 25 Kg/m2) in a case-control study. Additionally, in a prospective longitudinal study, we measured changes in the frequency of LDN after bariatric surgery (n=36) and tested for associations with metabolic and inflammatory parameters.

FINDINGS

LDN and inflammatory markers were significantly increased in MOP compared to NWC. Transcriptome analysis showed increased neutrophil-related gene expression signatures associated with inflammation, neutrophil activation, and immunosuppressive function. However, LDN did not suppress T cells proliferation and produced low levels of reactive oxygen species (ROS). Circulating LDN in MOP significantly decreased after bariatric surgery in parallel with BMI, metabolic syndrome, and inflammatory markers.

INTERPRETATION

Obesity increases LDN displaying an inflammatory gene signature. Our results suggest that LDN may represent a neutrophil subset associated with chronic inflammation, a feature of obesity that has been previously associated with the appearance and progression of co-morbidities. Furthermore, bariatric surgery, as an efficient therapy for severe obesity, reduces LDN in circulation and improves several components of the metabolic syndrome supporting its recognized anti-inflammatory and beneficial metabolic effects.

FUNDING

This work was supported in part by grants from the National Institutes of Health (NIH; 5P30GM114732-02, P20CA233374 - A. Ochoa and L. Miele), Pennington Biomedical NORC (P30DK072476 - E. Ravussin & LSU-NO Stanley S. Scott Cancer Center and Louisiana Clinical and Translational Science Center (LACaTS; U54-GM104940 - J. Kirwan).

An Explanation for the Adiponectin Paradox

The adipokine adiponectin improves insulin sensitivity. Functional signal transduction of adiponectin requires at least one of the receptors AdipoR1 or AdipoR2, but additionally the glycosyl phosphatidylinositol-anchored molecule, T-cadherin. Overnutrition causes a reduction in adiponectin synthesis and an increase in the circulating levels of the enzyme glycosyl phosphatidylinositol-phospholipase D (GPI-PLD). GPI-PLD promotes the hydrolysis of T-cadherin. The functional consequence of T-cadherin hydrolysis is a reduction in adiponectin sequestration by responsive tissues, an augmentation of adiponectin levels in circulation and a (further) reduction in signal transduction. This process creates the paradoxical situation that adiponectin levels are augmented, whereas the adiponectin signal transduction and insulin sensitivity remain strongly impaired. Although both hypoadiponectinemia and hyperadiponectinemia reflect a situation of insulin resistance, the treatments are likely to be different.

Dysregulated Inflammation During Obesity: Driving Disease Severity in Influenza Virus and SARS-CoV-2 Infections

Acute inflammation is a critical host defense response during viral infection. When dysregulated, inflammation drives immunopathology and tissue damage. Excessive, damaging inflammation is a hallmark of both pandemic influenza A virus (IAV) infections and Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) infections. Chronic, low-grade inflammation is also a feature of obesity. In recent years, obesity has been recognized as a growing pandemic with significant mortality and associated costs. Obesity is also an independent risk factor for increased disease severity and death during both IAV and SARS-CoV-2 infection. This review focuses on the effect of obesity on the inflammatory response in the context of viral respiratory infections and how this leads to increased viral pathology. Here, we will review the fundamentals of inflammation, how it is initiated in IAV and SARS-CoV-2 infection and its link to disease severity. We will examine how obesity drives chronic inflammation and trained immunity and how these impact the immune response to IAV and SARS-CoV-2. Finally, we review both medical and non-medical interventions for obesity, how they impact on the inflammatory response and how they could be used to prevent disease severity in obese patients. As projections of global obesity numbers show no sign of slowing down, future pandemic preparedness will require us to consider the metabolic health of the population. Furthermore, if weight-loss alone is insufficient to reduce the risk of increased respiratory virus-related mortality, closer attention must be paid to a patient’s history of health, and new therapeutic options identified.