Relationship(s) between obesity and inflammatory bowel diseases: possible intertwined pathogenic mechanisms

Recommendations on the management of severe obesity in patients with inflammatory bowel disease of the Spanish Group on Crohn's Disease and Ulcerative Colitis (GETECCU), Spanish Society of Obesity (SEEDO), Spanish Association of Surgery (AEC) and Spanish Society of Digestive Endoscopy (SEED)

Obesity is a multifactorial, chronic, progressive and recurrent disease considered a public health issue worldwide and an important determinant of disability and death. In Spain, its current prevalence in the adult population is about 24% and an estimated prevalence in 2035 of 37%. Obesity increases the probability of several diseases linked to higher mortality such as diabetes, cardiovascular disease, hyperlipidemia, arterial hypertension, non-alcoholic fatty liver disease, several types of cancer, or obstructive sleep apnea. On the other hand, although the incidence of inflammatory bowel disease (IBD) is stabilizing in Western countries, its prevalence already exceeds 0.3%. Paralleling to general population, the current prevalence of obesity in adult patients with IBD is estimated at 15-40%. Obesity in patients with IBD could entail, in addition to its already known impact on disability and mortality, a worse evolution of the IBD itself and a worse response to treatments. The aim of this document, performed in collaboration by four scientific societies involved in the clinical care of severe obesity and IBD, is to establish clear and concise recommendations on the therapeutic possibilities of severe or typeIII obesity in patients with IBD. The document establishes general recommendations on dietary, pharmacological, endoscopic, and surgical treatment of severe obesity in patients with IBD, as well as pre- and post-treatment evaluation.

Shotgun Analysis of Gut Microbiota with Body Composition and Lipid Characteristics in Crohn's Disease

Alterations to intestinal microbiota are assumed to occur in the pathogenesis of inflammatory bowel disease (IBD). This study aims to analyze the association of fecal microbiota composition, body composition, and lipid characteristics in patients with Crohn's disease (CD). In our cross-sectional study, patients with CD were enrolled and blood and fecal samples were collected. Clinical and endoscopic disease activity and body composition were assessed and laboratory tests were made. Fecal bacterial composition was analyzed using the shotgun method. Microbiota alterations based on obesity, lipid parameters, and disease characteristics were analyzed. In this study, 27 patients with CD were analyzed, of which 37.0% were obese based on visceral fat area (VFA). Beta diversities were higher in non-obese patients (p < 0.001), but relative abundances did not differ. C. innocuum had a higher abundance at a high cholesterol level than Bacillota (p = 0.001, p = 0.0034). Adlercreutzia, B. longum, and Blautia alterations were correlated with triglyceride levels. Higher Clostridia (p = 0.009) and B. schinkii (p = 0.032) and lower Lactobacillus (p = 0.035) were connected to high VFA. Disease activity was coupled with dysbiotic elements. Microbiota alterations in obesity highlight the importance of gut microbiota in diseases with a similar inflammatory background and project therapeutic options.

A correlation of serum fibroblast growth factor 21 level with inflammatory markers and indicators of nutritional status in patients with inflammatory bowel disease

Background

Fibroblast growth factor 21 (FGF21) is a stress-inducible hormone that regulates nutrient and metabolic homeostasis. Inflammatory state is one of the stimulators of FGF21 secretion. The aim of the study was to assess correlations between serum FGF21 level and inflammatory markers as well as nutritional status indicators in patients with inflammatory bowel disease (IBD).

Methods

Fasting serum FGF21 level was measured using ELISA test in 105 IBD patients and 17 healthy controls. There were 31 subjects with active ulcerative colitis (UC), 16 with inactive UC, 36 with active Crohn's disease (CD), and 22 with inactive CD. Clinical and endoscopic activity of IBD was evaluated based on validated scales and indices. Fecal calprotectin, serum CRP, and selected parameters of nutritional status were tested in all patients.

Results

Serum FGF21 level was characterized by fluctuations depending on the IBD activity. FGF21 level was significantly higher in both active UC and CD compared to inactive phases of the diseases and to the controls. A correlation between FGF21 and fecal calprotectin levels was also found in UC and CD. Additionally, in CD, FGF21 level positively correlated with CRP level. In both UC and CD, a negative correlation was noted between FGF21 level and nutritional status parameters including cholesterol, protein, albumin levels, and BMI.

Conclusion

The intensity of intestinal inflammation is related to FGF21 level, which correlates negatively with nutritional status indicators in IBD. The disturbances in FGF21 secretion may contribute to the multifactorial pathogenesis of malnutrition and weight loss in IBD patients.

The association of ultra-processed food consumption with adult inflammatory bowel disease risk: a systematic review and dose-response meta-analysis of 4 035 694 participants

CONTEXT

There is an inconsistency between the results obtained from observational studies regarding intake of ultra-processed foods (UPFs) and the risk of inflammatory bowel disease (IBD).

OBJECTIVES

A dose-response meta-analysis was performed to evaluate the relationship between UPF intake and the risk of IBD.

DATA SOURCES

Searches were performed in the PubMed, ISI Web of Science, and Scopus databases up to November 2, 2022.

DATA EXTRACTION

Data were available from 24 studies including a total of 4 035 694 participants from 20 countries.

DATA ANALYSIS

Risk ratios for IBD were analyzed by a random-effects model. Outcomes indicated that UPF intake was linked to an increased risk of IBD (relative risk [RR], 1.13; 95%CI, 1.06-1.21; P = 0.001; I2 = 73.2%; n = 59; N = 4 035 694). This association was significant, especially for the risk of Crohn's disease (CD) (RR, 1.19; 95%CI, 1.00-1.41; I2 = 78.2%; P = 0.046; n = 23; N = 2 167 160), unlike the risk of ulcerative colitis (UC) (RR = 1.11; 95%CI, 0.99-1.26; P = 0.085; I2 = 60.3%; n = 27; N = 2 167 918). Also, results revealed that each 10% enhancement in daily UPF intake was not related to the risk of IBD (RR, 1.05; 95%CI, 0.98-1.14; P = 0.168; I2 = 31.9%; n = 4) or the risk of UC (RR, 1.01; 95%CI, 0.92-1.11; P = 0.876; I2 = 34.7%; n = 2) in adults. However, results suggested that for every 10% increase in daily UPF intake, there was a 19% increase in the risk of CD (RR, 1.19; 95%CI, 1.01-1.32; P = 0.021; I2 = 0.0%; n = 2) among adults. In addition, the results showed a positive linear relation between UPF intake with CD risk (Pnonlinearity = 0.431; Pdose response = 0.049) but not risk of IBD or UC.

CONCLUSION

High intake of UPFs was linked with an enhanced IBD risk, a specific risk of CD. However, conducting more observational studies among several ethnicities and using specific tools that accurately assess the amount of UPF consumption, components of UPFs, and food additives may be necessary. Systematic Review Registration: PROSPERO registration no. CRD42023390258.

The value of whole-body dual-energy x-ray absorptiometry in assessing body composition in patients with inflammatory bowel disease: a prospective study

OBJECTIVES

Low skeletal muscle index (SMI) is common in inflammatory bowel disease (IBD) but has an uncertain relationship with active intestinal inflammation. This study evaluated body composition by whole-body dual-energy X-ray absorptiometry (DXA) in patients with IBD and healthy controls to enable the value of formal body composition analysis to be judged.

METHODS

Patients with IBD and sex/age-matched controls prospectively underwent full body composition assessment by DXA, assessment by BMI, eating questionnaires and handgrip strength. Disease activity was assessed by faecal calprotectin (active ≥150 µg/g). A cohort undergoing biologic induction therapy were assessed at baseline and after ≥13 weeks.

RESULTS

Total fat mass was higher in 54 patients with IBD (56% Crohn's disease, 61% male) than in 30 controls (median 25.1 vs. 18.7 kg, P  = 0.042). DXA offered little more than BMI. Low SMI was more common than in controls (15% vs. 0%, P  = 0.027). A normal BMI was seen in many patients with low SMI and handgrip strength was a poor marker of change in SMI. Body composition was similar in 28 patients with active vs. 22 with inactive disease. However, SMI increased specifically by 9.7% ( P  = 0.004) and BMI by 6.4% ( P  = 0.012) in 9 responders to therapy.

CONCLUSION

DXA identifies many patients with reduced SMI who are not detected by standard methodologies. While disease activity is not associated with low SMI, resolution of inflammation leads to improved SMI. The potential for recognition of such patients to influence therapeutic decisions underlines the need for DXA assessment in clinical practice.

Non-alcoholic fatty liver disease (NAFLD) and obesity in inflammatory bowel disease (IBD) patients in Gorgan

Background

According to the significance of extraintestinal symptoms in inflammatory bowel disease (IBD) patients and their connection with obesity, we aimed to investigate the prevalence of fatty liver in IBD patients of Sayyad Shirazi Hospital in Gorgan, Iran, in relation to obesity, anthropometric indicators and body image in these patients.

Methods

Forty patients with IBD were recruited from all registered patients at the Golestan Research Center of Gastroenterology and Hepatology, following the specified inclusion and exclusion criteria. After obtaining written informed consent and filling in the questionnaire, the demographic and anthropometric indicators, and variables related to the disease were measured. The liver sonography was performed on all patients and graded by an expert radiologist. Data were analyzed using SPSS Version 16.0 statistical software at the significance level of 0.05.

Results

We showed no significant difference between the distribution of demographic and anthropometric indicators in different groups of IBD patients. However, we demonstrated that the inappropriate values of HDL (0.004) and high values of LDL (0.015) were associated with fatty liver in IBD patients. Our findings also showed that NAFLD was significantly associated with overweight and obesity among IBD patients (P = 0.003).

Conclusion

Our findings showed the epidemiological burden of NAFLD in IBD patients. Since fatty liver was associated with obesity, it is recommended that IBD patients be screened for risk factors associated with NAFLD to prevent liver disease.

Global Impacts of Western Diet and Its Effects on Metabolism and Health: A Narrative Review

The Western diet is a modern dietary pattern characterized by high intakes of pre-packaged foods, refined grains, red meat, processed meat, high-sugar drinks, candy, sweets, fried foods, conventionally raised animal products, high-fat dairy products, and high-fructose products. The present review aims to describe the effect of the Western pattern diet on the metabolism, inflammation, and antioxidant status; the impact on gut microbiota and mitochondrial fitness; the effect of on cardiovascular health, mental health, and cancer; and the sanitary cost of the Western diet. To achieve this goal, a consensus critical review was conducted using primary sources, such as scientific articles, and secondary sources, including bibliographic indexes, databases, and web pages. Scopus, Embase, Science Direct, Sports Discuss, ResearchGate, and the Web of Science were used to complete the assignment. MeSH-compliant keywords such "Western diet", "inflammation", "metabolic health", "metabolic fitness", "heart disease", "cancer", "oxidative stress", "mental health", and "metabolism" were used. The following exclusion criteria were applied: (i) studies with inappropriate or irrelevant topics, not germane to the review's primary focus; (ii) Ph.D. dissertations, proceedings of conferences, and unpublished studies. This information will allow for a better comprehension of this nutritional behavior and its effect on an individual's metabolism and health, as well as the impact on national sanitary systems. Finally, practical applications derived from this information are made.

FGF21 Depletion Attenuates Colitis through Intestinal Epithelial IL-22-STAT3 Activation in Mice

Fibroblast growth factor 21 (FGF21) is a glucose and lipid metabolic regulator. Recent research revealed that FGF21 was also induced by inflammatory stimuli. Its role in inflammatory bowel disease (IBD) has not been investigated. In this study, an experimental IBD model was established in FGF21 knockout (KO) and wild-type (WT) mice by adding 2.5% (wt/vol) dextran sodium sulfate (DSS) to their drinking water for 7 days. The severity of the colitis and the inflammation of the mouse colon tissues were analyzed. In WT mice, acute DSS treatment induced an elevation in plasma FGF21 and a significant loss of body weight in a time-dependent manner. Surprisingly, the loss of body weight and the severity of the colitis induced by DSS treatment in WT mice were significantly attenuated in FGF21 KO mice. Colon and circulating pro-inflammatory factors were significantly lower in the FGF21 KO mice compared to the WT mice. As shown by BrdU staining, the FGF21 KO mice demonstrated increased colonic epithelial cell proliferation. DSS treatment reduced intestinal Paneth cell and goblet cell numbers in the WT mice, and this effect was attenuated in the FGF21 KO mice. Mechanistically, FGF21 deficiency significantly increased the signal transducer and activator of transcription (STAT)-3 activation in intestinal epithelial cells and increased the expression of IL-22. Further study showed that the expression of suppressor of cytokine signaling-2/3 (SOCS 2/3), a known feedback inhibitor of STAT3, was significantly inhibited in the DSS-treated FGF2 KO mice compared to the WT mice. We conclude that FGF21 deficiency attenuated the severity of DSS-induced acute colitis, which is likely mediated by enhancing the activation of the IL-22-STAT3 signaling pathway in intestinal epithelial cells.

Practical guideline on obesity care in patients with gastrointestinal and liver diseases - Joint ESPEN/UEG guideline

BACKGROUND

Patients with chronic gastrointestinal disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean gastrointestinal patients. The present guideline addresses this question according to current knowledge and evidence.

OBJECTIVE

The present practical guideline is intended for clinicians and practitioners in general medicine, gastroenterology, surgery and other obesity management, including dietitians and focuses on obesity care in patients with chronic gastrointestinal diseases.

METHODS

The present practical guideline is the shortened version of a previously published scientific guideline developed according to the standard operating procedure for ESPEN guidelines. The content has been re-structured and transformed into flow-charts that allow a quick navigation through the text.

RESULTS

In 100 recommendations (3× A, 33× B, 24 × 0, 40× GPP, all with a consensus grade of 90% or more) care of gastrointestinal patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially metabolic associated liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician.

CONCLUSION

The present practical guideline offers in a condensed way evidence-based advice how to care for patients with chronic gastrointestinal diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.

Weight Loss During Neoadjuvant Therapy Is Associated With Poor Response Among the Patients With Gastrointestinal Cancer: A Propensity Score Matching Analysis

PURPOSE

The aim of the current study was to identify the relationship between body composition changes during neoadjuvant therapy (NAT) and the treatment efficiency of NAT in gastrointestinal cancer (GC) patients.

METHODS

From January 2015 to July 2020, 277 GC patients treated with NAT had included for retrospective analysis. The body mass index (BMI) and computed tomography (CT) imaging before and after NAT were recorded. The BMI change optimal cut-off value were calculated by ROC curve. Balancing essential characteristic variables using propensity score matching (PSM) method. Exploring the association between BMI changes and tumor response to NAT using logistic regression analysis. The survival outcome of matched patients between different BMI change groups was compared.

RESULTS

A cutoff point of BMI change >2% during NAT was defined as BMI loss. Among the 277 patients, 110 (39.7%) patients showed BMI change with a loss after NAT. In total, 71 pairs of patients were selected for further analysis. The median follow-up time was 22 months (range 3 to 63 months). Univariate and multivariate logistic regression analyses in matched cohort showed that BMI change was a prognostic factor for tumor response after NAT in GC patients (odds ratio (OR), .471; 95% confidence interval (CI), .233-.953; P = .036). In addition, patients who experienced BMI loss after NAT showed worse overall survival than those who had BMI gain or stable.

CONCLUSION

BMI loss during NAT probably may has negative effects on NAT efficiency and survival for gastrointestinal cancer patients. It is necessary to monitor and maintain weight for patients during treatment.

Role of gastrointestinal microbial populations, a terra incognita of the human body in the management of intestinal bowel disease and metabolic disorders

Intestinal bowel disease (IBD) is a chronic immune-mediated clinical condition that affects the gastrointestinal tract and is mediated by an inflammatory response. Although it has been extensively studied, the multifactorial aetiology of this disorder makes it difficult to fully understand all the involved mechanisms in its development and therefore its treatment. In recent years, the fundamental role played by the human microbiota in the pathogenesis of IBD has been emphasised. Microbial imbalances in the gut bacterial communities and a lower species diversity in patients suffering from inflammatory gastrointestinal disorders compared to healthy individuals have been reported as principal factors in the development of IBD. These served to support scientific arguments for the use of probiotic microorganisms in alternative approaches for the prevention and treatment of IBD. In a homeostatic environment, the presence of bacteria (including probiotics) on the intestinal epithelial surface activates a cascade of processes by which immune responses inhibited and thereby commensal organisms maintained. At the same time these processes may support activities against specific pathogenic bacteria. In dysbiosis, these underlying mechanisms will serve to provoke a proinflammatory response, that, in combination with the use of antibiotics and the genetic predisposition of the host, will culminate in the development of IBD. In this review, we summarised the main causes of IBD, the physiological mechanisms involved and the related bacterial groups most frequently associated with these processes. The intention was to enable a better understanding of the interaction between the intestinal microbiota and the host, and to suggest possibilities by which this knowledge can be useful for the development of new therapeutic treatments.

Impact of Obesity on the Course of Management of Inflammatory Bowel Disease—A Review

It is already well-known that visceral adipose tissue is inseparably related to the pathogenesis, activity, and general outcome of inflammatory bowel disease (IBD). We are getting closer and closer to the molecular background of this loop, finding certain relationships between activated mesenteric tissue and inflammation within the lumen of the gastrointestinal tract. Recently, relatively new data have been uncovered, indicating a direct impact of body fat on the pattern of pharmacological treatment in the course of IBD. On the other hand, ileal and colonic types of Crohn’s disease and ulcerative colitis appear to be more diversified than it was thought in the past. However, the question arises whether at this stage we are able to translate this knowledge into the practical management of IBD patients or we are still exploring the scientific background of this pathology, having no specific tools to be used directly in patients. Our review explores IBD in the context of obesity and associated disorders, focusing on adipokines, creeping fat, and possible relationships between these disorders and the treatment of IBD patients.

European guideline on obesity care in patients with gastrointestinal and liver diseases - Joint ESPEN/UEG guideline

BACKGROUND

Patients with chronic gastrointestinal (GI) disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean GI patients. The present guideline addresses this question according to current knowledge and evidence.

OBJECTIVE

The objective of the guideline is to give advice to all professionals working in the field of gastroenterology care including physicians, surgeons, dietitians and others how to handle patients with GI disease and obesity.

METHODS

The present guideline was developed according to the standard operating procedure for ESPEN guidelines, following the Scottish Intercollegiate Guidelines Network (SIGN) grading system (A, B, 0, and good practice point (GPP)). The procedure included an online voting (Delphi) and a final consensus conference.

RESULTS

In 100 recommendations (3x A, 33x B, 24x 0, 40x GPP, all with a consensus grade of 90% or more) care of GI patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially fatty liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician.

CONCLUSION

The present guideline offers for the first time evidence-based advice how to care for patients with chronic GI diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.

Biological Activities Underlying the Therapeutic Effect of Quercetin on Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic autoimmune disorder stemming from unrestrained immune activation and subsequent destruction of colon tissue. Genetic susceptibility, microbiota remodeling, and environmental cues are involved in IBD pathogenesis. Up to now, there are limited treatment options for IBD, so better therapies for IBD are eagerly needed. The therapeutic effects of naturally occurring compounds have been extensively investigated, among which quercetin becomes an attractive candidate owing to its unique biochemical properties. To facilitate the clinical translation of quercetin, we aimed to get a comprehensive understanding of the cellular and molecular mechanisms underlying the anti-IBD role of quercetin. We summarized that quercetin exerts the anti-IBD effect through consolidating the intestinal mucosal barrier, enhancing the diversity of colonic microbiota, restoring local immune homeostasis, and restraining the oxidative stress response. We also delineated the effect of quercetin on gut microbiome and discussed the potential side effects of quercetin administration. Besides, quercetin could serve as a prodrug, and the bioavailability of quercetin is improved through chemical modifications or the utilization of effective drug delivery systems. Altogether, these lines of evidence hint the feasibility of quercetin as a candidate compound for IBD treatment.

Antioxidant Stress and Anti-Inflammatory Activities of Egg White Proteins and Their Derived Peptides: A Review

Oxidative stress and chronic inflammation are the common pathological bases of chronic diseases such as atherosclerosis, cancer, and cardiovascular diseases, but most of the treatment drugs for chronic diseases have side effects. There is an increasing interest to identify food-derived bioactive compounds that can mitigate the pathological pathways associated with oxidative stress and chronic inflammation. Egg white contain a variety of biologically active proteins, many of which have antioxidant and anti-inflammatory activities and usually show better activity after enzymatic hydrolysis. This review covers the antioxidative stress and anti-inflammatory activities of egg white proteins and their derived peptides and clarifies their mechanism of action in vivo and in vitro. In addition, the link between oxidative stress and inflammation as well as their markers are reviewed. It suggests the potential application of egg white proteins and their derived peptides and puts forward further research prospects.

Impact of Obesity on Inflammatory Bowel Disease

PURPOSE OF REVIEW

This review highlights recent work that evaluates the impact of obesity on inflammatory bowel disease (IBD) pathogenesis and management.

RECENT FINDINGS

The impact of obesity on IBD prevalence, clinical course, and management, has been studied and described more so in recent years. Studies have shown that obesity increases IBD disease activity, leads to longer hospitalization courses, and increases the likelihood of the development of extraintestinal manifestations. Recent evidence has also suggested that obese IBD patients have a higher frequency of extended steroid treatment and increased use of antibiotics compared to non-obese IBD patients. The effect of obesity on patients with IBD is a topic that has garnered widespread interest in the last decade due to the increasing prevalence of both diseases. To date however, although there are still many unanswered questions. It is quite clear that obesity, and more specifically, visceral adiposity, affects numerous IBD-related outcomes in regard to pathogenesis, extra-intestinal manifestations, response to medical and surgical therapies, hospital length of stay, healthcare-related costs, and health-related quality of life. Future studies should include larger patient populations and evaluate additional factors that are altered in those with obesity including the gut microbiome, dietary patterns, and whether weight loss and/or degree of weight loss impact clinical outcomes.

Exploring Links Between Industrialization, Urbanization, and Chinese Inflammatory Bowel Disease

Background: Evidence is emerging that the incidence of inflammatory bowel diseases (IBD) is dramatically increased in China, but with a geographic variation. Objectives: We performed a review to summarize the link of accelerated industrialization, urbanization to changing trends in the incidence of IBD over the last three decades. Methods: An electronic database search was performed in PubMed, Medline, EMBASE and Google Scholar (for English literature) and the China Science Periodical Database in Wanfang Data (for Chinese literature) from January 1990 to June 2020. Results: By systematically analyzing the changing trends of gross domestic product (GDP) or GDP per capita, population migration from rural areas to cities and increasing incidence of IBD in parallel in different Chinese regions, an association between accelerated industrialization and urbanization and rising rate of IBD was shown. In which, rates of IBD incidence were higher in provinces with a high value of GDP per capita than those provinces with a low value of GDP per capita. Analysis of available epidemiological data revealed that the incidence of IBD was rising in parallel with increasing trends of both gross products of industry and urban population in Yunnan Province in a 14-year interval. Further evidence suggested that industrialization- and urbanization-induced subsequent changes in environmental factors, e.g., Westernized dietary habits and obesity, and work-related stress, might contribute to the increased risk of IBD in China. In addition, the preliminary results showed that urbanization and Westernized dietary habits might induce significant changes in gut microbiota profile that are possibly to increase the risk for IBD in Chinese. Conclusions: Existing evidence to suggest that accelerated industrialization/urbanization is associated with the increasing incidence of IBD in China, which provides novel insights to study the possible mechanisms for the recent increasing incidence of IBD in newly industrialized and urbanized developing countries. In the future, the interaction between relevant environmental factors e.g., air/water pollution and IBD susceptibility genes in Chinese should be examined.

Spirulina platensis Consumption Prevents Obesity and Improves the Deleterious Effects on Intestinal Reactivity in Rats Fed a Hypercaloric Diet

The consumption of hypercaloric diets is related to the development of obesity, favoring the etiology of gastrointestinal disorders. In this context, Spirulina platensis (SP), some blue-green algae with antioxidant action, appears as a potential therapeutic alternative to prevent obesity and associated intestinal disorders. Thus, the present study is aimed at evaluating the deleterious effects of the hypercaloric diet on the contractile and relaxing reactivity of the ileum of rats, as well as the possible preventive mechanisms of dietary supplementation with SP. Wistar rats were divided into three groups: fed a standard diet (SD), a hypercaloric diet (HCD), and/or supplemented with 25 mg/kg SP (HCD + SP25) for 8 weeks. The hypercaloric diet was effective in promoting obesity in rats, as well as decreasing potency and ileal relaxing and contractile efficacy. In contrast, dietary supplementation with SP was able to prevent some of the parameters of experimental obesity. In addition, SP prevented the reduction of intestinal reactivity, possibly due to a positive modulation of voltage-gated calcium channels (CaV) and negative regulation of muscarinic receptors (M3). Thus, food supplementation with Spirulina platensis becomes a promising alternative in the prevention of gastrointestinal diseases induced and/or aggravated by obesity.

A nationwide analysis on the influence of obesity in inflammatory bowel disease hospitalizations

Background/Aims

Proinflammatory cytokines released from adipocytes can influence the development, progression, and treatment of inflammatory bowel disease (IBD), and may be associated with worse clinical outcomes.

Methods

For 2016–2018, we analyzed data from the Nationwide Inpatient Sample to identify adult (≥18 years) hospitalizations with a primary discharge diagnosis of IBD. The study sample was divided based on the presence or absence of obesity. The primary outcomes included inpatient mortality, while the secondary outcomes consisted of system-based complications and disease implications on the United States healthcare system.

Results

We identified 282,005 hospitalizations of IBD from 2016 to 2018. Of these hospitalizations, 26,465 (9.4%) had a secondary diagnosis of obesity while 255,540 (90.6%) served as controls. IBD hospitalizations with obesity had a higher mean age (47.9 years vs. 45.2 years, P<0.001), middle age (range, 40–65 years) predominance (37.7% vs. 28.9%, P<0.001), female predominance (64.1% vs. 52.5%, P<0.001) and higher proportion of patients with comorbidities compared to the non-obese cohort. White predominance was observed in both subgroups. No difference in the odds of inpatient mortality was noted between the 2 subgroups; however, IBD hospitalizations with obesity had higher mean total hospital charge ($50,126 vs. $45,001, P<0.001), longer length of stay (5.5 days vs. 4.9 days, P<0.001) and higher proportion of complications compared to the non-obese cohort.

Conclusions

Obese IBD hospitalizations had higher length of stay, total hospital charge, and complications compared to the non-obese cohort.

Alterations of Gut Microbiota in Patients With Graves' Disease

Graves' disease (GD) is a systemic autoimmune disease characterized by hyperthyroidism. Evidence suggests that alterations to the gut microbiota may be involved in the development of autoimmune disorders. The aim of this study was to characterize the composition of gut microbiota in GD patients. Fecal samples were collected from 55 GD patients and 48 healthy controls. Using 16S rRNA gene amplification and sequencing, the overall bacterial richness and diversity were found to be similar between GD patients and healthy controls. However, principal coordinate analysis and partial least squares-discriminant analysis showed that the overall gut microbiota composition was significantly different (ANOSIM; p < 0.001). The linear discriminant analysis effect size revealed that Firmicutes phylum decreased in GD patients, with a corresponding increase in Bacteroidetes phylum compared to healthy controls. In addition, the families Prevotellaceae, and Veillonellaceae and the genus Prevotella_9 were closely associated with GD patients, while the families Lachnospiraceae and Ruminococcaceae and the genera Faecalibacterium, Lachnospira, and Lachnospiraceae NK4A136 were associated with healthy controls. Metagenomic profiles analysis yielded 22 statistically significant bacterial taxa: 18 taxa were increased and 4 taxa were decreased. Key bacterial taxa with different abundances between the two groups were strongly correlated with GD-associated clinical parameters using Spearman's correlation analysis. Importantly, the discriminant model based on predominant microbiota could effectively distinguish GD patients from healthy controls (AUC = 0.825). Thus, the gut microbiota composition between GD patients and healthy controls is significantly difference, indicating that gut microbiota may play a role in the pathogenesis of GD. Further studies are needed to fully elucidate the role of gut microbiota in the development of GD.

Role of Adipose Tissue in Inflammatory Bowel Disease

Inflammatory bowel diseases (IBDs), chronic inflammatory disorders affecting the gastrointestinal tract, include Crohn's disease and ulcerative colitis. There are increasing clinical and experimental data showing that obesity, especially visceral adiposity, plays a substantial role in the pathogenesis of IBD. Obesity seems to be an important risk factor also for IBD disease severity and clinical outcomes. Visceral adipose tissue is an active multifunctional metabolic organ involved in lipid storage and immunological and endocrine activity. Bowel inflammation penetrates the surrounding adipose tissue along the mesentery. Mesenteric fat serves as a barrier to inflammation and controls immune responses to the translocation of gut bacteria. At the same time, mesenteric adipose tissue may be the principal source of cytokines and adipokines responsible for inflammatory processes associated with IBD. This review is particularly focusing on the potential role of adipokines in IBD pathogenesis and their possible use as promising therapeutic targets.

Carboxylesterase 2 proteins are efficient diglyceride and monoglyceride lipases possibly implicated in metabolic disease

Carboxylesterase 2 (CES2/Ces2) proteins exert established roles in (pro)drug metabolism. Recently, human and murine CES2/Ces2c have been discovered as triglyceride (TG) hydrolases implicated in the development of obesity and fatty liver disease. The murine Ces2 family consists of seven homologous genes as opposed to a single CES2 gene in humans. However, the mechanistic role of Ces2 protein family members is not completely understood. In this study, we examined activities of all Ces2 members toward TGs, diglycerides (DGs), and monoglycerides (MGs) as the substrate. Besides CES2/Ces2c, we measured significant TG hydrolytic activities for Ces2a, Ces2b, and Ces2e. Notably, these Ces2 members and CES2 efficiently hydrolyzed DGs and MGs, and their activities even surpassed those measured for TG hydrolysis. The localization of CES2/Ces2c proteins at the ER may implicate a role of these lipases in lipid signaling pathways. We found divergent expression of Ces2 genes in the liver and intestine of mice on a high-fat diet, which could relate to changes in lipid signaling. Finally, we demonstrate reduced CES2 expression in the colon of patients with inflammatory bowel disease and a similar decline in Ces2 expression in the colon of a murine colitis model. Together, these results demonstrate that CES2/Ces2 members are highly efficient DG and MG hydrolases that may play an important role in liver and gut lipid signaling.

Global associations of national economic wealth are more robust with inflammatory bowel diseases than with obesity

The inflammatory bowel diseases consisting of Crohn's and ulcerative colitis have expanded into previously low incidence areas of the world. The spread follows the relatively recent pandemic of global obesity. Pathological relations have been proposed between these two diseases. Both inflammatory bowel diseases and obesity originated in wealthier western societies marked by high gross domestic product per capita. The pathogenic influence of national wealth on the inflammatory bowel diseases has been recognized but are less clear with obesity. Parallel correlations of national wealth with obesity would further strengthen relations between these two diseases. Alternatively, diverging relations could suggest that obesity is less dependent on wealth. As such it would supports another earlier hypothesis that obesity depends on adoption of western diet which precedes national acquisition of wealth. Previously ecological modifiers of global disease patterns, including latitude and lactose digestion status have shown different influences on IBD compared with obesity. We evaluate. the influence of the Gross Domestic Product on these two diseases taking into consideration the former's relationship with ecological markers. Patterns of correlations could suggest contributing mechanisms how these ecological parameters influence some disease distributions. The literature and internet were searched for national rates of obesity, inflammatory bowel diseases, national gross domestic product per capita and national lactase distribution rates. National average latitudes were calculated previously. Pearson correlations were used to compare variables in three regions; global, European and Asian theaters. SAS statistical package was used and statistical significance was accepted at p < 0.05. Globally and in Europe correlations of gross domestic product were moderate and significant r = 0.55 and r = 0.6 respectively with Crohn's disease but weaker with ulcerative colitis. The results were negligible in Asia. Obesity was weakly correlated with gross domestic product globally r = 0.32 and negligible in Europe and Asia. In addition, gross domestic product was moderately correlated with latitude r = 0.6, and inversely with lactase non persistence r = -0.6 both globally and in Europe. This relationship is similar to that with inflammatory bowel diseases, but less related to obesity. Overall results suggest unequal effect of national wealth and industrialization on obesity and inflammatory bowel diseases. It has been suggested that western type diet precedes full industrialization and this could promote obesity.

Impact of Body Mass Index on the Development of Inflammatory Bowel Disease: A Systematic Review and Dose-Response Analysis of 15.6 Million Participants

BACKGROUND

A growing trove of literature describes the effect of malnutrition and underweight on the incidence of inflammatory bowel disease (IBD). However, evidence regarding the association between underweight or obesity and IBD is limited. The study aimed to assess the association of body mass index (BMI) with a risk of IBD (Crohn's disease (CD) and ulcerative colitis (U.C.)) incidence.

METHODS

We systematically searched PubMed/Medline, Cochrane, Web of Science, and Scopus for observational studies assessing the association between BMI and IBD that were published up to 30 June 2020. We estimated pooled hazard ratios (HR) with corresponding 95% confidence intervals (CI). Random effect dose-response meta-analysis was performed using the variance weighted least-squares regression (VWLS) models to identify non-linear associations.

RESULTS

A total of ten studies involving 15.6 million individuals and 23,371 cases of IBD were included. Overall, obesity was associated with an increased IBD risk (HR: 1.20, 95% CI: 1.08-1.34, I 2 = 0%). Compared to normal weight, underweight (BMI < 18.5 kg/m2) and obesity (BMI ≥ 30 kg/m2) were associated with a higher risk of CD, and there was no difference in the risk of U.C. among those with BMI < 18.5 kg/m2 and BMI ≥ 30 kg/m2. There was a significant non-linear association between being underweight and obesity and the risk of development of CD (Coef1 = -0.0902, p 1 < 0.001 Coef2 = 0.0713, p 2 < 0.001).

CONCLUSIONS

Obesity increases the risk of IBD development. Underweight and obesity are independently associated with an increased risk of CD, yet there is no evident association between BMI and the risk of U.C. Further studies are needed to clarify the underlying mechanism for these findings, particularly in CD.

Blockage of protease-activated receptor 2 exacerbates inflammation in high-fat environment partly through autophagy inhibition

Protease-activated receptor 2 (PAR2) regulates inflammatory responses and lipid metabolism. However, its precise role in colitis remains unclear. In this study, we aimed to investigate the function of PAR2 in high-fat diet-fed mice with colitis and its potential role in autophagy. PAR2^+/+ and PAR2^-/- mice were fed a high-fat diet (HFD) for 7 days before colitis induction with dextran sodium sulfate. Deletion of PAR2 and an HFD significantly exacerbated colitis, as shown by increased mortality, body weight loss, diarrhea or bloody stools, colon length shortening, and mucosal damage. Proinflammatory cytokine levels were elevated in HFD-fed PAR2^-/- mice and in cells treated with the PAR2 antagonist GB83, palmitic acid (PA), and a cytokine cocktail (CC). Damaging effects of PAR2 blockage were associated with autophagy regulation by reducing the levels of YAP1, SIRT1, PGC-1α, Atg5, and LC3A/B-I/II. In addition, mitochondrial dysfunction was demonstrated only in cells treated with GB83, PA, and CC. Reduced cell viability and greater induction of apoptosis, as shown by increased levels of cleaved caspase-9, cleaved caspase-3, and cleaved poly(ADP-ribose) polymerase (PARP), were observed in cells treated with GB83, PA, and CC but not in those treated with only PA and CC. Collectively, protective effects of PAR2 were elucidated during inflammation accompanied by a high-fat environment by promoting autophagy and inhibiting apoptosis, suggesting PAR2 as a therapeutic target for inflammatory bowel disease co-occurring with metabolic syndrome.NEW & NOTEWORTHY Deletion of PAR2 with high-fat diet feeding exacerbates colitis in a murine colitis model. Proinflammatory effects of PAR2 blockage in a high-fat environment were associated with an altered balance between autophagy and apoptosis. Increased colonic levels of PAR2 represent as a therapeutic strategy for IBD co-occurring with metabolic syndrome.

Fungal lysozyme leverages the gut microbiota to curb DSS-induced colitis

Colitis is characterized by colonic inflammation and impaired gut health. Both features aggravate obesity and insulin resistance. Host defense peptides (HDPs) are key regulators of gut homeostasis and generally malfunctioning in above-mentioned conditions. We aimed here to improve bowel function in diet-induced obesity and chemically induced colitis through daily oral administration of lysozyme, a well-characterized HDP, derived from Acremonium alcalophilum.C57BL6/J mice were fed either low-fat reference diet or HFD ± daily gavage of lysozyme for 12 weeks, followed by metabolic assessment and evaluation of colonic microbiota encroachment. To further evaluate the efficacy of intestinal inflammation, we next supplemented chow-fed BALB/c mice with lysozyme during Dextran Sulfate Sodium (DSS)-induced colitis in either conventional or microbiota-depleted mice. We assessed longitudinal microbiome alterations by 16S amplicon sequencing in both models.Lysozyme dose-dependently alleviated intestinal inflammation in DSS-challenged mice and further protected against HFD-induced microbiota encroachment and fasting hyperinsulinemia. Observed improvements of intestinal health relied on a complex gut flora, with the observation that microbiota depletion abrogated lysozyme's capacity to mitigate DSS-induced colitis.Akkermansia muciniphila associated with impaired gut health in both models, a trajectory that was mitigated by lysozyme administration. In agreement with this notion, PICRUSt2 analysis revealed specific pathways consistently affected by lysozyme administration, independent of vivarium, disease model and mouse strain.Taking together, lysozyme leveraged the gut microbiota to curb DSS-induced inflammation, alleviated HFD-induced gastrointestinal disturbances and lowered fasting insulin levels in obese mice. Collectively, these data present A. alcalophilum-derived lysozyme as a promising candidate to enhance gut health.

Characterization of the serum levels of Meteorin-like in patients with inflammatory bowel disease and its association with inflammatory cytokines

Background

Meteorin-like (Metrnl) is an adipokine with insulin sensitizing and anti-inflammatory properties that has been discovered recently. The relation among Metrnl, Inflammatory Bowel Disease (IBD), and obesity has been unexplored yet.

Methods

The present study was conducted on 54 healthy control, 42 Ulcerative Colitis (UC), and 43 Crohn’s disease (CD) patients who were diagnosed by pathological examination. In all participants, serum levels of adiponectin, Metrnl, interleukin (IL)-6, and Tumor necrosis factor (TNF-α) were measured using ELISA kits.

Results

Metrnl concentration was considerably lower in both UC (85.25 ± 36.55 pg/mL) and CD (76.93 ± 27.92 pg/mL) patients in comparison to control (107.52 ± 35.33 pg/mL). In addition, it was seen that both patient groups have a decreased level of adiponectin compared to the controls. Besides that, the level of IL-6 and TNF-α were significantly greater in the patient groups. Moreover, the result showed that the level of Metrnl is inversely correlated with body mass index (BMI) in the controls and the patients. Metrnl levels are also inversely associated with IL-6, and TNF-α in both of the patient groups.

Conclusions

The current study is the first one reporting the decreased levels of Metrnl in serum among patients with IBD, which is inversely related with BMI, TNF-α, and IL-6. These results suggested a possible relation of Metrnl with the pathogenesis of IBD, particularly through inflammatory process, although further studies are warranted to dissect the possible mechanism.

What was First, Obesity or Inflammatory Bowel Disease? What Does the Gut Microbiota Have to Do with It?

A sedentary lifestyle and inadequate nutrition often leads to disturbances in intestinal homeostasis, which may predispose people to excess body weight and metabolic syndrome. Obesity is frequently observed in patients with inflammatory bowel diseases (IBD), similar to the general population. Obesity may exert a negative effect on the course of IBD as well as reduce the response to treatment. Moreover, it may also be an additional risk factor for vein thromboembolism during the flare. In both obesity and IBD, it is of great importance to implement proper dietary ingredients that exert desirable effect on gut microbiota. The key to reducing body mass index (BMI) and alleviating the course of IBD is preserving healthy intestinal microflora.

Gastrointestinal Disorders and Metabolic Syndrome: Dysbiosis as a Key Link and Common Bioactive Dietary Components Useful for their Treatment

Gastrointestinal (GI) diseases, which include gastrointestinal reflux disease, gastric ulceration, inflammatory bowel disease, and other functional GI disorders, have become prevalent in a large part of the world population. Metabolic syndrome (MS) is cluster of disorders including obesity, hyperglycemia, hyperlipidemia, and hypertension, and is associated with high rate of morbidity and mortality. Gut dysbiosis is one of the contributing factors to the pathogenesis of both GI disorder and MS, and restoration of normal flora can provide a potential protective approach in both these conditions. Bioactive dietary components are known to play a significant role in the maintenance of health and wellness, as they have the potential to modify risk factors for a large number of serious disorders. Different classes of functional dietary components, such as dietary fibers, probiotics, prebiotics, polyunsaturated fatty acids, polyphenols, and spices, possess positive impacts on human health and can be useful as alternative treatments for GI disorders and metabolic dysregulation, as they can modify the risk factors associated with these pathologies. Their regular intake in sufficient amounts also aids in the restoration of normal intestinal flora, resulting in positive regulation of insulin signaling, metabolic pathways and immune responses, and reduction of low-grade chronic inflammation. This review is designed to focus on the health benefits of bioactive dietary components, with the aim of preventing the development or halting the progression of GI disorders and MS through an improvement of the most important risk factors including gut dysbiosis.

Changing Patterns of Relationships Between Geographic Markers and IBD: Possible Intrusion of Obesity

Background

Latitude and lactase digestion status influence incidence and prevalence rates of some noncommunicable diseases. Latitudinal correlations helped define beneficial roles of vitamin D in many diseases like inflammatory bowel disease (IBD). In view of recent global expansion of IBD and population migrations, we reexamine relations with these markers. As these changes also paralleled the pandemic of obesity, we explore possible interactions with IBD.

Methods

We undertook a literature review to compare rates of obesity, Crohn's disease and ulcerative colitis with the geographic markers of lactase digestion status, average population-weighted national latitude, and national yearly sunshine exposure. Pearson correlations were used throughout to determine r correlation factors. Statistical significance was accepted at P <0.05 using 2-tailed tests.

Results

Forty-seven countries were matched with various data sets that could be analyzed (range of availability was 49%-85%). While global correlations of IBD with latitude and lactase status remain similar to previous analyses, in Europe and Asia, outcomes were different. Global outcome contains a statistical paradox related to combining countries from Europe and Asia. Obesity showed moderate global correlations with IBD but weak and negligible correlations in Europe and Asia. There was also a weak global correlation with latitude.

Conclusions

It is suggested that global correlations point to parallel geographic spread of IBD and obesity. The lack of latitudinal relations with obesity suggests reduced vitamin D effect. The paradox supports epidemiological differences in western and eastern IBD. Obesity combined with IBD may contribute to different relations, partly due to variable vitamin D effects.