Adipose tissue extrinsic factor: Obesity-induced inflammation and the role of the visceral lymph node

Does the Ketogenic Diet Mediate Inflammation Markers in Obese and Overweight Adults? A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Background/Objectives. The ketogenic diet has emerged as a potential treatment strategy for reducing inflammation. The purpose of this meta-analysis and systematic review is to look into how a ketogenic diet affects inflammatory biomarkers in persons who are overweight or obese. Methods. We conducted an extensive search of Web of Science, PubMed, Scopus, and Google Scholar to find pertinent studies reporting changes in inflammatory biomarkers such as C-reactive protein (CRP), the erythrocyte sedimentation rate, and cytokines after a ketogenic diet. Results. Seven randomized controlled trials involving 218 overweight or obese individuals who followed a ketogenic or control diet over 8 weeks to 2 years were included in the review, and five of those were considered for the meta-analysis. The primary outcomes were CRP and IL-6 levels. The results reported significant decreases after treatment for CRP (mean of -0.62 mg/dL (95% CI: -0.84, -0,40), and a slight, but not statistically significant, reduction in IL-6 (mean of -1.31 pg/mL (95% CI: -2.86, 0.25). Conclusions. The ketogenic diet could contribute to modulating inflammation in obese and overweight subjects.

The Possible Associations between Tauopathies and Atherosclerosis, Diabetes Mellitus, Dyslipidemias, Metabolic Syndrome and Niemann-Pick Disease

Clinical evaluation and treatment of tauopathic syndromes remain a challenge. There is a growing interest in theories concerning their possible associations with metabolic diseases. The possible connection between those diseases might be linked with cerebrovascular dysfunction. The endothelial cell damage and impairment of the blood-brain barrier observed in atherosclerosis or diabetes may play a role in contributing to tauopathic syndrome development. Additionally, the inflammation evoked by pathological metabolic changes may also be involved in this process. Multiple cases indicate the coexistence of metabolic disorders and tauopathic syndromes. These findings suggest that modifying the evolution of metabolic and cerebrovascular diseases may impact the course of neurodegenerative diseases. Obtained data could indicate the possible benefits of introducing routine carotid artery sonography, revascularization operation or antihypertensive medications among patients at high risk for tauopathies. This review has identified this understudied area, which is currently associated with several diseases for which there is no treatment. Due to the pathomechanisms linking metabolic diseases and tauopathies, further investigation of this area of research, including cohort studies, is recommended and may provide new pharmacological perspectives for treatment.

The Influence of FAM13A and PPAR-γ2 Gene Polymorphisms on the Metabolic State of Postmenopausal Women

Recently, we have observed two significant pandemics caused by communicable (COVID-19) and non-communicable factors (obesity). Obesity is related to a specific genetic background and characterized by immunogenetic features, such as low-grade systemic inflammation. The specific genetic variants include the presence of polymorphism of the Peroxisome Proliferator-Activated Receptors gene (PPAR-γ2; Pro12Ala, rs1801282, and C1431T, rs3856806 polymorphisms), β-adrenergic receptor gene (3β-AR; Trp64Arg, rs4994), and Family With Sequence Similarity 13 Member A gene (FAM13A; rs1903003, rs7671167, rs2869967). This study aimed to analyze the genetic background, body fat distribution, and hypertension risk in obese metabolically healthy postmenopausal women (n = 229, including 105 lean and 124 obese subjects). Each patient underwent anthropometric and genetic evaluations. The study has shown that the highest value of BMI was associated with visceral fat distribution. The analysis of particular genotypes has revealed no differences between lean and obese women except for FAM13A rs1903003 (CC), which was more prevalent in lean patients. The co-existence of the PPAR-γ2 C1431C variant with other FAM13A gene polymorphisms [rs1903003(TT) or rs7671167(TT), or rs2869967(CC)] was related to higher BMI values and visceral fat distribution (WHR > 0.85). The co-association of FAM13A rs1903003 (CC) and 3β-AR Trp64Arg was associated with higher values of systolic (SBP) and diastolic blood pressure (DBP). We conclude that the co-existence of FAM13A variants with C1413C polymorphism of the PPAR-γ2 gene is responsible for body fat amount and distribution.

Very low calorie ketogenic diet and common rheumatic disorders: A case report

BACKGROUND

The scientific literature provides evidence that nutritional ketosis can be an important support in the treatment of pathologies in which inflammation is present, as recent studies have shown that ketone bodies have anti-inflammatory activity in numerous diseases, including rheumatic diseases. We report the case of a 22-year-old woman with class I obesity and juvenile idiopathic arthritis who started treatment with a very low calorie ketogenic diet (VLCKD).

CASE SUMMARY

The patient was a 22-year-old woman diagnosed with juvenile idiopathic arthritis at age 4 years and with a body mass index (BMI) of 30.8 kg/m², waist circumference (WC) 80 cm, fat mass (FM) 28.1 kg, free FM 45.7 kg, and visceral adipose tissue (VAT) 3.5 kg, assessed on bioimpedance analysis. She was treated using a commercial VLCKD weight-loss program (PNK^® method); this program provides high-biological-value protein preparations and natural foods. Each protein preparation contains 15 g protein, 4 g carbohydrate, 3 g fat, and 50 mg omega-3 docosahexaenoic acid, with an energy content of 90–120 kcal. After four months on the program, the BMI was 28.6 kg/m², WC 73 cm, FM 23.2 kg, free FM 41.9 kg, and VAT 2.9 kg.

CONCLUSION

VLCKD enabled the patient to reach her target weight and to reduce her joint pain and headaches. Laboratory inflammatory indices also normalized.

A Potential Link Between Visceral Obesity and Risk of Alzheimer's Disease

Alzheimer's disease (AD) is the most common type of dementia characterized by the deposition of amyloid beta (Aβ) plaques and tau-neurofibrillary tangles in the brain. Visceral obesity (VO) is usually associated with low-grade inflammation due to higher expression of pro-inflammatory cytokines by adipose tissue. The objective of the present review was to evaluate the potential link between VO and the development of AD. Tissue hypoxia in obesity promotes tissue injury, production of adipocytokines, and release of pro-inflammatory cytokines leading to an oxidative-inflammatory loop with induction of insulin resistance. Importantly, brain insulin signaling is involved in the pathogenesis of AD and lower cognitive function. Obesity and enlargement of visceral adipose tissue are associated with the deposition of Aβ. All of this is consonant with VO increasing the risk of AD through the dysregulation of adipocytokines which affect the development of AD. The activated nuclear factor kappa B (NF-κB) pathway in VO might be a potential link in the development of AD. Likewise, the higher concentration of advanced glycation end-products in VO could be implicated in the pathogenesis of AD. Taken together, different inflammatory signaling pathways are activated in VO that all have a negative impact on the cognitive function and progression of AD except hypoxia-inducible factor 1 which has beneficial and neuroprotective effects in mitigating the progression of AD. In addition, VO-mediated hypoadiponectinemia and leptin resistance may promote the progression of Aβ formation and tau phosphorylation with the development of AD. In conclusion, VO-induced AD is mainly mediated through the induction of oxidative stress, inflammatory changes, leptin resistance, and hypoadiponectinemia that collectively trigger Aβ formation and neuroinflammation. Thus, early recognition of VO by visceral adiposity index with appropriate management could be a preventive measure against the development of AD in patients with VO.

Altered acetyl-CoA metabolism presents a new potential immunotherapy target in the obese lung microenvironment

Contrary to the "obesity paradox," which arises from retrospective studies relying on body mass index to define obesity, epidemiologic evidence suggests central or visceral obesity is associated with a higher risk for the development of lung cancer. About 60% of individuals at high risk for developing lung cancer or those already with early-stage disease are either overweight or obese. Findings from resected patient tumors and mouse lung tumor models show obesity dampens immune activity in the tumor microenvironment (TME) encouraging disease progression. In line with this, we have observed a marked, obesity-specific enhancement in the presence and phenotype of immunosuppressive regulatory T (Treg) cells in murine tumors as well as the airways of both humans and mice. Leveraging direct metabolomic measurements and robust inferred analyses from RNA-sequencing data, we here demonstrate for the first time that visceral adiposity alters the lung microenvironment via dysregulated acetyl-CoA metabolism in a direction that facilitates immune suppression and lung carcinogenesis.

The Association Between Visceral Obesity and Postoperative Outcomes in Elderly Patients With Colorectal Cancer

Background

The impact of visceral obesity on the postoperative complications of colorectal cancer in elderly patients has not been well studied. This study aims to explore the influence of visceral obesity on surgical outcomes in elderly patients who have accepted a radical surgery for colorectal cancer.

Methods

Patients aged over 65 year who had undergone colorectal cancer resections from January 2015 to September 2020 were enrolled. Visceral obesity is typically evaluated based on visceral fat area (VFA) which is measured by computed tomography (CT) imaging. Univariate and multivariate analyses were performed to analyze parameters related to short-term outcomes.

Results

A total of 528 patients participated in this prospective study. Patients with visceral obesity exhibited the higher incidence of total (34.1% vs. 18.0%, P < 0.001), surgical (26.1% vs. 14.6%, P = 0.001) and medical (12.6% vs. 6.7%, P = 0.022) complications. Based on multivariate analysis, visceral obesity and preoperative poorly controlled hypoalbuminemia were considered as independent risk factors for postoperative complications in elderly patients after colorectal cancer surgery.

Conclusions

Visceral obesity, evaluated by VFA, was a crucial clinical predictor of short-term outcomes after colorectal cancer surgery in elderly patients. More attentions should be paid to these elderly patients before surgery.

Effect of very low-calorie ketogenic diet in combination with omega-3 on inflammation, satiety hormones, body composition, and metabolic markers. A pilot study in class I obese subjects

PURPOSE

This study aims to evaluate the effects of a VLCKD combined with omega-3 supplementation (VLCKD diet only lasted for some weeks, and it was followed by a non-ketogenic LCD for the rest of the study period) on body composition, visceral fat, satiety hormones, inflammatory and metabolic markers.

METHODS

It has been performed a pilot open label study lasted 90 days, in a cohort of 12 women with class I obesity aged 18 to 65 years. Data on body composition (evaluated by Dual X-Ray Absorptiometry-DXA), visceral fat, satiety hormones, inflammatory and metabolic markers were recorded.

RESULTS

This study showed a body weight reduction mean difference over time of -13.7 kg and the waist circumference mean difference decrease of -13.3 cm. Also, the fat mass (FM) decreased-9.1 kg and visceral adipose tissue (VAT)-0.41 kg. No effects on fat-free mass (FFM) have been reported. Improvements were observed in the satiety hormones, with increased ghrelin and decreased leptin, and also in the metabolic profiles.

CONCLUSIONS

A VLCKD combined with omega-3 supplementation appears to be an effective strategy for promoting an high loss of FM with preservation of FFM in patients with class I obesity.

Type 3 resistant starch from Canna edulis modulates obesity and obesity-related low-grade systemic inflammation in mice by regulating gut microbiota composition and metabolism

Obesity is a most prevalent human health problem. Several studies showed that appropriate modulation of gut microbiota could help reshape the metabolic profile of obese individuals, thereby altering the development of obesity. A nutritional strategy for treating obesity includes prebiotics. Type 3 Resistant Starch from Canna edulis (Ce-RS3) is a dietary fiber that exerts potential effects on the intestinal microbial community; however, the metabolic landscape and anti-obesity mechanism remain unclear. In the present study, obese mice were treated with Ce-RS3, and 16S rRNA gene sequencing and metabolomics were used to measure changes in gut microbiota and fecal metabolic profiles, respectively. At the end of the treatment (13 weeks), we observed slow weight gain in the mice, and pathological damage and inflammation were substantially reduced. Ce-RS3 constructs a healthy gut microbiota structure and can enhance intestinal immunity and reduce metabolic inflammation. Ce-RS3 increased the diversity of gut microbiota with enrichment of Bifidobacterium and Roseburia. Ce-RS3 regulated the systemic metabolic dysbiosis in obese mice and adjusted 26 abnormal metabolites in amino acids and lipids metabolism, many of which are related to the microbiome. More importantly, we found that the anti-obesity effect of Ce-RS3 can be transferred by fecal transplantation. The beneficial effects of Ce-RS3 might derive from gut microbiota changes, which might improve obesity and metabolic inflammation by altering host-microbiota interactions with impacts on the metabolome. In conclusion, Ce-RS3 can be used as a prebiotic with potential value for the treatment of obesity.

Relationship of the neutrophil/lymphocyte ratio with cardiovascular risk markers in premenopausal and postmenopausal women

Introduction

Cardiovascular disease is more frequent in postmenopausal women. Atherosclerosis is associated with inflammation and the neutrophil/lymphocyte ratio (NLR) is a marker of inflammation whose behavior in postmenopause is unknown.

Aim of the study

To know the relationship of the NLR with cardiovascular risk markers in premenopausal and postmenopausal women.

Material and methods

Premenopausal and postmenopausal women were studied, in all of them a complete hemogram and the NLR, platelet/lymphocyte ratio (PLR) were calculated, also glucose and lipids levels were measured. In all of them subcutaneous and visceral fat, carotid intima-media thickness (IMT), epicardial fat were measured by ultrasound Also baseline and and after flow-mediated stimulus the arterial diameter, the pulsatility index and the resistive index of the brachial artery were measured by ultrasound. The results are reported with medians and intervals, Mann-Whitney U and Spearman correlation analysis were performed.

Results

Eighty two patients were recruited, 41 premenopausal and 41 postmenopausal. When comparing both groups there was no difference in glucose, lipids, NLR, PLR, carotid IMT, epicardial fat, subcutaneous fat, visceral fat or Doppler parameters of the brachial artery.

Conclusion

NLR was not different between premenopausal and postmenopausal women but abnormal PLR was greater in those postmenopausal with vasomotor symptoms.

Effects of Very Low Calorie Ketogenic Diet on the Orexinergic System, Visceral Adipose Tissue, and ROS Production

BACKGROUND

Caloric restriction is a valid strategy to reduce the visceral adipose tissue (VAT) content in obese persons. Hypocretin-1 (orexin-A) is a neuropeptide synthesized in the lateral hypothalamus that strongly modulates food intake, thus influencing adipose tissue accumulation. Therapeutic diets in obesity treatment may combine the advantages of caloric restriction and dietary ketosis. The current study aimed to evaluate the effect of a very low calorie ketogenic diet (VLCKD) in a population of obese patients.

METHODS

Adiposity parameters and orexin-A serum profiling were quantified over an 8 week period. The effect of the VLCKD on reactive oxygen species (ROS) production and cell viability was evaluated, in vitro, by culturing Hep-G2 cells in the presence of VLCKD sera.

RESULTS

Dietary intervention induced significant effects on body weight, adiposity, and blood chemistry parameters. Moreover, a selective reduction in VAT was measured by dual-energy X-ray absorptiometry. Orexin-A levels significantly increased after dietary treatment. Hep-G2 cell viability was not affected after 24, 48, and 72 h incubation with patients' sera, before and after the VLCKD. In the same model system, ROS production was not significantly influenced by dietary treatment.

CONCLUSION

The VLCKD exerts a positive effect on VAT decrease, ameliorating adiposity and blood chemistry parameters. Furthermore, short-term mild dietary ketosis does not appear to have a cytotoxic effect, nor does it represent a factor capable of increasing oxidative stress. Finally, to the best of our knowledge, this is the first study that shows an effect of the VLCKD upon the orexinergic system, supporting the usefulness of such a therapeutic intervention in promoting obesity reduction in the individual burden of this disease.

Summary of the 2018 Alcohol and Immunology Research Interest Group (AIRIG) meeting

On January 26, 2018, the 23rd annual Alcohol and Immunology Research Interest Group (AIRIG) meeting was held at the University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado. The meeting consisted of plenary sessions with oral presentations and a poster presentation session. There were four plenary sessions that covered a wide range of topics relating to alcohol use: Alcohol and Liver Disease; Alcohol, Inflammation and Immune Response; Alcohol and Organ Injury; Heath Consequences and Alcohol Drinking. The meeting provided a forum for the presentation and discussion of novel research findings regarding alcohol use and immunology.

Oleoylethanolamide treatment affects gut microbiota composition and the expression of intestinal cytokines in Peyer's patches of mice

The lipid sensor oleoylethanolamide (OEA), an endogenous high-affinity agonist of peroxisome proliferator-activated receptor-α (PPAR-α) secreted in the proximal intestine, is endowed with several distinctive homeostatic properties, such as control of appetite, anti-inflammatory activity, stimulation of lipolysis and fatty acid oxidation. When administered exogenously, OEA has beneficial effects in several cognitive paradigms; therefore, in all respects, OEA can be considered a hormone of the gut-brain axis. Here we report an unexplored modulatory effect of OEA on the intestinal microbiota and on immune response. Our study shows for the first time that sub-chronic OEA administration to mice fed a normal chow pellet diet, changes the faecal microbiota profile, shifting the Firmicutes:Bacteroidetes ratio in favour of Bacteroidetes (in particular Bacteroides genus) and decreasing Firmicutes (Lactobacillus), and reduces intestinal cytokines expression by immune cells isolated from Peyer's patches. Our results suggest that sub-chronic OEA treatment modulates gut microbiota composition towards a "lean-like phenotype", and polarises gut-specific immune responses mimicking the effect of a diet low in fat and high in polysaccharides content.

Adipose tissue inflammation and metabolic syndrome. The proactive role of probiotics

PURPOSE

The first part of this review focuses on the role of cells and molecules of adipose tissue involved in metabolic syndrome-induced inflammation and in the maintenance of this pathology. In the second part of the review, the potential role of probiotics-modulating metabolic syndrome-related inflammatory components is summarized and discussed.

METHODS

The search for the current scientific literature was carried out using ScienceDirect, PubMed, and Google Scholar search engines. The keywords used were: metabolic syndrome, obesity, insulin resistant, adipose tissue, adipose tissue inflammation, chronic low-grade inflammation, immune cells, adipokines, cytokines, probiotics, and gut microbiota.

RESULTS AND CONCLUSIONS

Chronic low-grade inflammation that characterized metabolic syndrome can contribute to the development of the metabolic dysfunctions involved in the pathogenesis of its comorbidities. Adipose tissue is a complex organ that performs metabolic and immune functions. During metabolic syndrome, an imbalance in the inflammatory components of adipose tissue (immune cells, cytokines, and adipocytokines), which shift from an anti-inflammatory to a pro-inflammatory profile, can provoke metabolic syndrome linked complications. Further knowledge concerning the immune function of adipose tissue may contribute to finding better alternatives for the treatment or prevention of such disorders. The control of inflammation could result in the management of many of the pathologies related to metabolic syndrome. Due to the strong evidence that gut microbiota composition plays a role modulating the body weight, adipose tissue, and the prevalence of a low-grade inflammatory status, probiotics emerge as valuable tools for the prevention of metabolic syndrome and health recovery.