-
1.
The trace aminergic system: a gender-sensitive therapeutic target for IBS?
Pretorius, L, Smith, C
Journal of biomedical science. 2020;(1):95
-
-
Free full text
-
Abstract
Due to a lack of specific or sensitive biomarkers, drug discovery advances have been limited for individuals suffering from irritable bowel syndrome (IBS). While current therapies provide symptomatic relief, inflammation itself is relatively neglected, despite the presence of chronic immune activation and innate immune system dysfunction. Moreover, considering the microgenderome concept, gender is a significant aetiological risk factor. We believe that we have pinpointed a "missing link" that connects gender, dysbiosis, diet, and inflammation in the context of IBS, which may be manipulated as therapeutic target. The trace aminergic system is conveniently positioned at the interface of the gut microbiome, dietary nutrients and by-products, and mucosal immunity. Almost all leukocyte populations express trace amine associated receptors and significant amounts of trace amines originate from both food and the gut microbiota. Additionally, although IBS-specific data are sparse, existing data supports an interpretation in favour of a gender dependence in trace aminergic signalling. As such, trace aminergic signalling may be altered by fluctuations of especially female reproductive hormones. Utilizing a multidisciplinary approach, this review discusses potential mechanisms of actions, which include hyperreactivity of the immune system and aberrant serotonin signalling, and links outcomes to the symptomology clinically prevalent in IBS. Taken together, it is feasible that the additional level of regulation by the trace aminergic system in IBS has been overlooked, until now. As such, we suggest that components of the trace aminergic system be considered targets for future therapeutic action, with the specific focus of reducing oxidative stress and inflammation.
-
2.
Colonic immune cells in irritable bowel syndrome: A systematic review and meta-analysis.
Bashashati, M, Moossavi, S, Cremon, C, Barbaro, MR, Moraveji, S, Talmon, G, Rezaei, N, Hughes, PA, Bian, ZX, Choi, CH, et al
Neurogastroenterology and motility. 2018;(1)
Abstract
BACKGROUND & AIMS Increases in mucosal immune cells have frequently been observed in irritable bowel syndrome (IBS) patients. However, this finding is not completely consistent between studies, possibly due to a combination of methodological variability, population differences and small sample sizes. We performed a meta-analysis of case-control studies that compared immune cell counts in colonic biopsies of IBS patients and controls. METHODS PubMed and Embase were searched in February 2017. Results were pooled using standardized mean difference (SMD) and were considered significant when zero was not within the 95% confidence interval (CI). Heterogeneity was assessed based on I2 statistics where I2 ≤ 50% and I2 > 50% indicated fixed and random effect models, respectively. KEY RESULTS Twenty-two studies on 706 IBS patients and 401 controls were included. Mast cells were increased in the rectosigmoid (SMD: 0.38 [95% CI: 0.06-0.71]; P = .02) and descending colon (SMD: 1.69 [95% CI: 0.65-2.73]; P = .001) of IBS patients. Increased mast cells were observed in both constipation (IBS-C) and diarrhea predominant IBS (IBS-D). CD3+ T cells were increased in the rectosigmoid (SMD: 0.53 [95% CI: 0.21-0.85]; P = .001) and the descending colon of the IBS patients (SMD: 0.79, 95% CI [0.28-1.30]; P = .002). This was possibly in relation to higher CD4+ T cells in IBS (SMD: 0.33 [95% CI: 0.01-0.65]; P = .04) as there were no differences in CD8+ T cells. CONCLUSIONS & INFERENCES Mast cells and CD3+ T cells are increased in colonic biopsies of patients with IBS vs non-inflamed controls. These changes are segmental and sometimes IBS-subtype dependent. The diagnostic value of the quantification of colonic mucosal cells in IBS requires further investigation.
-
3.
Mucosal pathobiology and molecular signature of epithelial barrier dysfunction in the small intestine in irritable bowel syndrome.
González-Castro, AM, Martínez, C, Salvo-Romero, E, Fortea, M, Pardo-Camacho, C, Pérez-Berezo, T, Alonso-Cotoner, C, Santos, J, Vicario, M
Journal of gastroenterology and hepatology. 2017;(1):53-63
Abstract
Irritable bowel syndrome (IBS) is one of the most prevalent gastrointestinal disorders in developed countries. Its etiology remains unknown; however, a common finding, regardless of IBS subtype, is the presence of altered intestinal barrier. In fact, signaling and location of cell-to-cell adhesion proteins, in connection with increased immune activity, seem abnormal in the intestinal epithelium of IBS patients. Despite that most research is performed on distal segments of the intestine, altered permeability has been reported in both, the small and the large bowel of all IBS subtypes. The small intestine carries out digestion and nutrient absorption and is also the site where the majority of immune responses to luminal antigens takes place. In fact, the upper intestine is more exposed to environmental antigens than the colon and is also a site of symptom generation. Recent studies have revealed small intestinal structural alterations of the epithelial barrier and mucosal immune activation in association with intestinal dysfunction, suggesting the commitment of the intestine as a whole in the pathogenesis of IBS. This review summarizes the most recent findings on mucosal barrier alterations and its relationship to symptoms arising from the small intestine in IBS, including epithelial structural abnormalities, mucosal immune activation, and microbial dysbiosis, further supporting the hypothesis of an organic origin of IBS.
-
4.
Personality traits and emotional patterns in irritable bowel syndrome.
Muscatello, MR, Bruno, A, Mento, C, Pandolfo, G, Zoccali, RA
World journal of gastroenterology. 2016;(28):6402-15
Abstract
The review focuses on those personality traits (neuroticism, extraversion, openness to experience, agreeableness, and conscientiousness), constructs (alexithymia and distressed - Type D personality) and emotional patterns (negative and positive) that are of particular concern in health psychology, with the aim to highlight their potential role on the pathogenesis, onset, symptom clusters, clinical course, and outcome of irritable bowel syndrome (IBS). Personality traits and emotional patterns play key roles in affecting autonomic, immune, inflammatory, and endocrine functions, thus contributing not only to IBS clinical expression and symptomatic burden, but also to disease physiopathology. In this sense, psychological treatments should address those personality traits and emotional features that are constitutive of, and integral to IBS. The biopsychosocial model of illness applied to IBS acknowledges the interaction between biological, psychological, environmental, and social factors in relation to pain and functional disability. A holistic approach to IBS should take into account the heterogeneous nature of the disorder, and differentiate treatments for different types of IBS, also considering the marked individual differences in prevalent personality traits and emotional patterns. Beyond medications, and lifestyle/dietary interventions, psychological and educational treatments may provide the optimal chance of addressing clinical symptoms, comorbid conditions, and quality of life in IBS patients.
-
5.
Effect of probiotic species on irritable bowel syndrome symptoms: A bring up to date meta-analysis.
Ortiz-Lucas, M, Tobías, A, Saz, P, Sebastián, JJ
Revista espanola de enfermedades digestivas. 2013;(1):19-36
Abstract
BACKGROUND AND OBJECTIVES immune system alteration in irritable bowel syndrome (IBS) patients may be modulated by probiotics. We assessed the efficacy of some probiotic species in alleviating characteristic IBS symptoms. MATERIAL AND METHODS a meta-analysis of all identified randomized controlled trials comparing probiotics with placebo in treating IBS symptoms was performed with continuous data summarized using standardized mean differences (SMDs) with 95% confidence intervals (95% CIs), where appropriate. The random-effects model was employed in cases of heterogeneity; otherwise, fixed-effects models were used. RESULTS meta-analysis was performed with 10 of 24 studies identified as suitable for inclusion. Probiotics improved pain scores if they contained Bifidobacterium breve (SMD, - 0.34; 95% CI, - 0.66; -0.02), Bifidobacterium longum (SMD, -0.48; 95% CI, - 0.91; -0.06), or Lactobacillus acidophilus (SMD, -0.31; 95% CI, -0.61; -0.01) species. Distension scores were improved by probiotics containing B. breve (SMD, -0.45; 95% CI, -0.77; -0.13), Bifidobacterium infantis, Lactobacillus casei, or Lactobacillus plantarum (SMD, -0.53; 95% CI, -1.00; -0.06) species. All probiotic species tested improved flatulence: B. breve (SMD, -0.42; 95% CI, -0.75;- 0.10), B. infantis, L. casei, L. plantarum (SMD, -0.60; 95% CI, -1.07; -0.13), B. longum, L. acidophilus, Lactobacillus bulgaricus, and Streptococcus salivarius ssp. thermophilus (SMD, -0.61; 95% CI, -1.01; -0.21). There was not a clear positive effect of probiotics concerning the quality of life. CONCLUSIONS some probiotics are an effective therapeutic option for IBS patients, and the effects on each IBS symptom are likely species-specific. Future studies must focus on the role of probiotics in modulating intestinal microbiota and the immune system while considering individual patient symptom profiles.
-
6.
The colonic microbiota and colonic disease.
Shanahan, F
Current gastroenterology reports. 2012;(5):446-52
Abstract
The colonic ecosystem differs from that in the proximal gut in several important respects. The colonic microbiota represents the largest population of microbes colonizing humans from birth. Constraints on bacterial numbers, composition, and interaction with the host involve not only the innate and acquired immune system, but also the colonic mucin structure. While the microbiota provides beneficial protective, trophic, nutritional, and metabolic signals for the host, it may become a risk factor for disease depending on context and host susceptibility. Technological advances including DNA-based high-throughput compositional analysis have linked changes in the indigenous microbiota with several human diseases. In some instances, these findings have the potential to serve as new biomarkers of risk of disease. In this overview, recent advances are focused upon in relation to irritable bowel syndrome, inflammatory bowel disease, and colon cancer. The possibility that the therapeutic solution to some of these disorders may reside within the microbiota will also be addressed.
-
7.
Probiotics use to treat irritable bowel syndrome.
Hosseini, A, Nikfar, S, Abdollahi, M
Expert opinion on biological therapy. 2012;(10):1323-34
Abstract
INTRODUCTION Irritable bowel syndrome (IBS) is a common chronic gastrointestinal (GI) tract disorder with significant disability and a considerable financial burden to health service due to the consumption of resources including investigations, physician time, and cost of treatment. Despite availability of multiple treatment options, there is still poor functional recovery. AREAS COVERED Probiotics has been investigated as a promising treatment for IBS, and have demonstrated beneficial effects in some patients. There are many clinical trials investigating the therapeutic benefits of probiotics in IBS but most of them are heterogenic in terms of dose or species used and clinical endpoints. However, recent major meta-analyses revealed benefits of probiotics in patients with IBS. Inhibition of binding of pathogenic bacteria to intestinal epithelial cells, enhancing barrier function of intestinal epithelial, acidification of the colon, suppression of the growth of pathogens, modulation of immunity, inhibition of visceral hypersensitivity, alteration in mucosal response to stress, and improvement of bowel dysmotility are among mechanisms that probiotics may act. Most commonly used probiotics come from the genera Bifidobacterium and Lactobacillus but other species are in trial. EXPERT OPINION Although further studies are still needed, current evidences are almost enough to convince experts that probiotics are efficient in the treatment of IBS.
-
8.
Review article: Probiotics in gastrointestinal and liver diseases.
Jonkers, D, Stockbrügger, R
Alimentary pharmacology & therapeutics. 2007;:133-48
-
-
Free full text
-
Abstract
BACKGROUND Probiotics, defined as live micro-organisms with beneficial effects for the host, are widely applied in gastrointestinal and liver diseases. AIM AND METHOD To review the available evidence of clinical trials on probiotics in gastrointestinal and liver diseases, with a major focus on irritable bowel syndrome, inflammatory bowel disease, pancreatitis and chronic liver diseases. RESULTS Evidence for the therapeutic or preventive application of particular probiotic strains is available for antibiotic-associated diarrhoea, rota-virus-associated diarrhoea and pouchitis. Results are encouraging for irritable bowel syndrome, ulcerative colitis and for reducing side effects by Helicobacter pylori eradication therapies, but are less clear for Crohn's disease, lactose intolerance and constipation. In general, for most of these patient groups, more placebo-controlled methodologically well-designed studies that pay attention to both clinical outcome and mechanistic aspects are required. The application in liver disease and pancreatitis is promising, but more human trials have to be awaited. Possible mechanisms of probiotics include modulation of the intestinal microbiota and the immune system, but different bacterial may have different effects. CONCLUSION Further insight into disease entities and the functioning of probiotic strains is required to be able to select disease-specific strains, which have to be tested in well-designed placebo-controlled studies.