Mechanisms of Disease: nicotine—a review of its actions in the context of gastrointestinal disease

Irritable Bowel Syndrome (IBS) and Smoking: An Evaluation of IBS symptom severity and anxiety sensitivity among adults in the United States

INTRODUCTION

Irritable bowel syndrome (IBS) is a prevalent disorder of gut-brain function associated with psychological distress as well as work and quality of life impairment. Smoking has been linked to gastrointestinal dysfunction, however, research focused on the prevalence of IBS and smoking is limited. Previous research has shown that anxiety sensitivity is linked to increased risk of aversive bodily experiences and subsequent coping-oriented regulation efforts. Higher anxiety sensitivity has also been associated with processes linked to tobacco cigarette smoking lapse and relapse. There is a need to clarify the explanatory roles of anxiety sensitivity in the context of more severe IBS symptoms among persons with IBS who are current smokers.

METHOD

The present investigation evaluated the main and interactive effects of IBS symptom severity and anxiety sensitivity in relation to processes related to the maintenance and relapse of tobacco smoking among adults with IBS. The sample consisted of 263 (52.1 % female; Mage = 44.13 years, SD = 12.71) adults who met criteria for IBS and smoke at least 5 cigarettes per day.

RESULTS

Hierarchical regression results indicated that both anxiety sensitivity and IBS symptom severity independently predicted greater perceived barriers to smoking cessation, severity of problems experienced during quitting, and negative reinforcement smoking expectancies. A statistically significant interaction further indicated that IBS symptom severity was more strongly associated with negative reinforcement smoking expectancies among participants with higher, relative to lower, anxiety sensitivity.

CONCLUSIONS

This study is the first to show that both IBS symptom severity and anxiety sensitivity are related to greater perceived barriers to smoking cessation, previous difficulty quitting, and negative reinforcement expectancies among adults with IBS. There is a continued need to further scientific understanding of interrelations between anxiety sensitivity, IBS symptom severity, and smoking cessation-related beliefs and processes to identify novel approaches that can best support quitting among this understudied population.

Leisure television watching exerts a causal effect on gastroesophageal reflux disease: evidence from a two-step mendelian randomization study

BACKGROUND

Previous studies have shown that physical activity (PA) and leisure sedentary behaviors (LSB, including leisure television watching) are linked to gastroesophageal reflux disease (GERD). However, the associations between PA/LSB and GERD remain controversial. In this study, we aimed to reveal whether these associations reflect causal relationships and reveal the potential mechanisms of these relationships using bidirectional and two-step Mendelian randomization (MR) analyses.

METHODS

We obtained genome-wide association study (GWAS) summary statistics for PA/LSB, four common risk factors (including cigarettes smoked per day, alcoholic drinks per week, triglycerides, total cholesterol) and GERD from published GWASs. A bidirectional MR analysis was performed to identify causal relationships between PA/LSB and GERD. Then, a series of sensitivity analyses were performed to verify the robustness of the results. Finally, a mediation analysis via two-step MR was conducted to investigate any effects explained by common risk factors in these relationships.

RESULTS

Genetically predicted per 1-SD increase in leisure time television watching significantly increased the risk of GERD in the bidirectional MR analysis (OR = 1.33; 95% CI: 1.14-1.56; P = 2.71 × 10- 4). Sensitivity analyses successfully verified the robustness of the causal relationship. Further mediation analysis showed that this effect was partly mediated by increasing cigarettes smoked per day, with mediated proportions of 18.37% (95% CI: 11.94-39.79%).

CONCLUSION

Our findings revealed a causal relationship between leisure television watching and an increased risk of GERD, notably, the causal effect was partially mediated by cigarettes smoked per day. These findings may inform prevention and management strategies directed toward GERD.

Functional evaluation of pure natural edible Ferment: protective function on ulcerative colitis

Purpose

To investigate the therapeutic efficiency of a novel drink termed "Ferment" in cases of ulcerative colitis (UC) and its influence on the gut microbiota.

Method

In this study, we developed a complex of mixed fruit juice and lactic acid bacteria referred to as Ferment. Ferment was fed to mice for 35 days, before inducing UC with Dextran Sulfate Sodium Salt. We subsequently investigated the gut microbiome composition using 16S rRNA sequencing.

Result

After Ferment treatment, mouse body weight increased, and animals displayed less diarrhea, reduced frequency of bloody stools, and reduced inflammation in the colon. Beneficial bacteria belonging to Ileibacterium, Akkermansia, and Prevotellacea were enriched in the gut after Ferment treatment, while detrimental organisms including Erysipelatoclostridium, Dubosiella, and Alistipes were reduced.

Conclusion

These data place Ferment as a promising dietary candidate for enhancing immunity and protecting against UC.

Factors associated with irritable bowel syndrome and Helicobacter pylori infection: public knowledge and awareness of signs and symptoms

OBJECTIVE

To investigate factors related to the risk of developing irritable bowel syndrome (IBS) or Helicobacter pylori infection.

METHODS

This cross-sectional, questionnaire-based study analysed the responses from participants that completed an online questionnaire, which asked about their knowledge of the causes and risk factors associated with IBS and H. pylori infection.

RESULTS

The study analysed responses from 230 participants: 181 females (of 227 participants; 79.7%) and 190 aged 18-40 years (of 228; 83.3%). Of the 230 participants, 40 (17.4%) had been diagnosed by a physician with IBS and 57 (24.8%) had been diagnosed with H. pylori infection. Of 226 participants, 93 (41.2%) had self-medicated with antibiotics in the past 6 months for various reasons. The overall mean ± SD knowledge score about IBS and H. pylori infection for the study cohort (n = 230) was 35.8 ± 19.2%. Wald χ2-test analysis demonstrated that chronic diseases, antibiotic use and having an endoscopy were significantly associated with developing IBS. Male sex and chronic diseases were significantly associated with H. pylori infection. Logistic regression analysis showed no relationship between IBS and H. Pylori infection.

CONCLUSION

Chronic diseases was the only risk factor common for IBS and H. pylori infection.

Bone marrow-derived mesenchymal stem cells mitigate chronic colitis and enteric neuropathy via anti-inflammatory and anti-oxidative mechanisms

Current treatments for inflammatory bowel disease (IBD) are often inadequate due to limited efficacy and toxicity, leading to surgical resection in refractory cases. IBD's broad and complex pathogenesis involving the immune system, enteric nervous system, microbiome, and oxidative stress requires more effective therapeutic strategies. In this study, we investigated the therapeutic potential of bone marrow-derived mesenchymal stem cell (BM-MSC) treatments in spontaneous chronic colitis using the Winnie mouse model which closely replicates the presentation and inflammatory profile of ulcerative colitis. The 14-day BM-MSC treatment regimen reduced the severity of colitis, leading to the attenuation of diarrheal symptoms and recovery in body mass. Morphological and histological abnormalities in the colon were also alleviated. Transcriptomic analysis demonstrated that BM-MSC treatment led to alterations in gene expression profiles primarily downregulating genes related to inflammation, including pro-inflammatory cytokines, chemokines and other biomarkers of inflammation. Further evaluation of immune cell populations using immunohistochemistry revealed a reduction in leukocyte infiltration upon BM-MSC treatment. Notably, enteric neuronal gene signatures were the most impacted by BM-MSC treatment, which correlated with the restoration of neuronal density in the myenteric ganglia. Moreover, BM-MSCs exhibited neuroprotective effects against oxidative stress-induced neuronal loss through antioxidant mechanisms, including the reduction of mitochondrial-derived superoxide and attenuation of oxidative stress-induced HMGB1 translocation, potentially relying on MSC-derived SOD1. These findings suggest that BM-MSCs hold promise as a therapeutic intervention to mitigate chronic colitis by exerting anti-inflammatory effects and protecting the enteric nervous system from oxidative stress-induced damage.

Adverse physiological effects of smoking cessation on the gastrointestinal tract: A review

Smoking cessation is known to have numerous health benefits, but it can also induce adverse physiological effects, including those affecting the gastrointestinal tract (GIT). Understanding the adverse physiological effects of smoking cessation on the GIT is critical for healthcare professionals and smokers attempting to quit, as it enables them to anticipate and manage potential challenges during the smoking cessation process. Although the detrimental effects of smoking on the GIT have been well established, there is a gap in the literature regarding the specific physiological reactions that may occur upon smoking cessation. This mini-review summarizes the current literature on the predisposing factors, pathophysiology, clinical presentation, and treatment options for adverse physiological effects of smoking cessation on the GIT. We aimed to raise awareness among busy clinical professionals about these adverse effects, empowering them to effectively support individuals striving to quit smoking and maintain their cessation. By consolidating the existing knowledge in this field, this review offers practical implications for smokers, healthcare providers, and policymakers to optimize smoking cessation interventions and support strategies to improve health outcomes.

Tobacco Smoking Is a Strong Predictor of Failure of Conservative Treatment in Hinchey IIa and IIb Acute Diverticulitis-A Retrospective Single-Center Cohort Study

Background and Objectives: Therapeutic management of patients with complicated acute diverticulitis remains debatable. The primary objective of this study is to identify predictive factors for the failure of conservative treatment of Hinchey IIa and IIb diverticular abscesses. Materials and Methods: This is a retrospective cohort study that included patients hospitalized from 1 January 2014 to 31 December 2022 at the Emergency Surgery Department of the Cagliari University Hospital (Italy), diagnosed with acute diverticulitis complicated by Hinchey grade IIa and IIb abscesses. The collected variables included the patient's baseline characteristics, clinical variables on hospital admission, abscess characteristics at the contrast-enhanced CT scan, clinical outcomes of the conservative therapy, and follow-up results. Univariable and multivariable logistic regression models were used to identify prognostic factors of conservative treatment failure and success. Results: Two hundred and fifty-two patients diagnosed with acute diverticulitis were identified from the database search, and once the selection criteria were applied, 71 patients were considered eligible. Conservative treatment failed in 25 cases (35.2%). Univariable analysis showed that tobacco smoking was the most significant predictor of failure of conservative treatment (p = 0.007, OR 7.33, 95%CI 1.55; 34.70). Age (p = 0.056, MD 6.96, 95%CI -0.18; 0.99), alcohol drinking (p = 0.071, OR 4.770, 95%CI 0.79; 28.70), platelets level (p = 0.087, MD -32.11, 95%CI -0.93; 0.06), Hinchey stage IIa/IIb (p = 0.081, OR 0.376, 95%CI 0.12; 1.11), the presence of retroperitoneal air bubbles (p = 0.025, OR 13.300, 95%CI 1.61; 291.0), and the presence of extraluminal free air at a distance (p = 0.043, OR 4.480, 95%CI 1.96; 20.91) were the other variables possibly associated with the risk of failure. In the multivariable logistic regression analysis, only tobacco smoking was confirmed to be an independent predictor of conservative treatment failure (p = 0.006; adjusted OR 32.693; 95%CI 2.69; 397.27). Conclusion: The role of tobacco smoking as a predictor of failure of conservative therapy of diverticular abscess scenarios highlights the importance of prevention and the necessity to reduce exposure to modifiable risk factors.

The controversial effect of smoking and nicotine in SARS-CoV-2 infection

The effects of nicotine and cigarette smoke in many diseases, notably COVID-19 infection, are being debated more frequently. The current basic data for COVID-19 is increasing and indicating the higher risk of COVID-19 infections in smokers due to the overexpression of corresponding host receptors to viral entry. However, current multi-national epidemiological reports indicate a lower incidence of COVID-19 disease in smokers. Current data indicates that smokers are more susceptible to some diseases and more protective of some other. Interestingly, nicotine is also reported to play a dual role, being both inflammatory and anti-inflammatory. In the present study, we tried to investigate the effect of pure nicotine on various cells involved in COVID-19 infection. We followed an organ-based systematic approach to decipher the effect of nicotine in damaged organs corresponding to COVID-19 pathogenesis (12 related diseases). Considering that the effects of nicotine and cigarette smoke are different from each other, it is necessary to be careful in generalizing the effects of nicotine and cigarette to each other in the conducted researches. The generalization and the undifferentiation of nicotine from smoke is a significant bias. Moreover, different doses of nicotine stimulate different effects (dose-dependent response). In addition to further assessing the role of nicotine in COVID-19 infection and any other cases, a clever assessment of underlying diseases should also be considered to achieve a guideline for health providers and a personalized approach to treatment.

Long-term outcomes and risk factors for diverticulitis recurrence after a successful laparoscopic peritoneal lavage in Hinchey III peritonitis

PURPOSE

Recently, treatment of Hinchey III diverticulitis by laparoscopic peritoneal lavage has been questioned. Moreover, long-term outcomes have been scarcely reported. Primary outcome was to determine the recurrence rate of diverticulitis after a successful laparoscopic peritoneal lavage in Hinchey III diverticulitis. Secondary outcomes were identification of associated risk factors for recurrence and elective sigmoidectomy rate.

METHODS

A retrospective cohort study in a tertiary referral center was performed. Patients with Hinchey III diverticulitis who underwent a successful laparoscopic peritoneal lavage between June 2006 and December 2019 were eligible. Diverticulitis recurrence was analyzed according to the Kaplan-Meier and log-rank test, censoring for death, loss of follow-up, or elective sigmoid resection in the absence of recurrence. Risk factors for recurrence were identified using Cox regression analysis.

RESULTS

Sixty-nine patients had a successful laparoscopic peritoneal lavage (mean age: 63 years; 53.6% women). Four patients had an elective sigmoid resection without recurrences. Recurrence rate was 42% (n = 29) after a median follow-up of 63 months. The cumulative global recurrence at 1, 3, and 5 years was 30% (95% CI, 20-43%), 37.5% (95% CI, 27-51%), and 48.9% (95% CI, 36-64%), respectively. Smoking (HR, 2.87; 95% CI, 1.22-6.5; p = 0.016) and episodes of diverticulitis prior to laparoscopic peritoneal lavage (HR, 5.2; 95% CI, 2.11-12.81; p < 0.001) were independently associated with an increased risk of recurrence.

CONCLUSIONS

Diverticulitis recurrence after a successful laparoscopic peritoneal lavage is high, decreasing after the first year of follow-up. Smoking and previous episodes of acute diverticulitis independently increase the risk of new episodes of diverticulitis.

Einfluss des Rauchens auf den Gastrointestinaltrakt

Hintergrund

Nikotin ist ein hochwirksames Suchtgift, das bei regelmäßiger Einnahme chronische oder unheilbare Erkrankungen und somit eine eingeschränkte Lebensqualität zur Folge haben kann.

Fragestellung

Das Ziel dieser Übersichtsarbeit besteht darin, mögliche gesundheitliche Folgen des Rauchens auf den Gastrointestinaltrakt aufzuzeigen und einen Überblick über raucherassoziierte neoplastische und nichtneoplastische gastrointestinale Erkrankungen zu geben.

Material und Methode

Anhand einer ausführlichen Literaturrecherche wird der aktuelle Wissensstand zu raucherassoziierten Folgen auf den Gastrointestinaltrakt dargestellt.

Ergebnisse

Rauchen ist ein wesentlicher Risikofaktor für die Entstehung neoplastischer und nichtneoplastischer Erkrankungen des gesamten Gastrointestinaltrakts. Diese weisen in der radiologischen Bildgebung allerdings keine spezifischen, raucherassoziierten Merkmale auf.

Schlussfolgerung

Die Kenntnis einer Raucheranamnese sowie möglicher Auswirkungen von Nikotin auf den Gastrointestinaltrakt können in der radiologischen Bildinterpretation hilfreich sein sowie die diagnostische Entscheidungsfähigkeit und Genauigkeit verbessern.

Manipulation of the inflammatory reflex as a therapeutic strategy

The cholinergic anti-inflammatory pathway is the efferent arm of the inflammatory reflex, a neural circuit through which the CNS can modulate peripheral immune responses. Signals communicated via the vagus and splenic nerves use acetylcholine, produced by Choline acetyltransferase (ChAT)+ T cells, to downregulate the inflammatory actions of macrophages expressing α7 nicotinic receptors. Pre-clinical studies using transgenic animals, cholinergic agonists, vagotomy, and vagus nerve stimulation have demonstrated this pathway's role and therapeutic potential in numerous inflammatory diseases. In this review, we summarize what is understood about the inflammatory reflex. We also demonstrate how pre-clinical findings are being translated into promising clinical trials, and we draw particular attention to innovative bioelectronic methods of harnessing the cholinergic anti-inflammatory pathway for clinical use.

Updates in the understanding and management of diverticular disease

PURPOSE OF REVIEW

Diverticulosis leads to significant morbidity and mortality and is increasing in prevalence worldwide. In this paper, we review the clinical features, diagnosis, and management of diverticular disorders, followed by a discussion of recent updates and changes in the clinical approach to diverticular disease.

RECENT FINDINGS

Recent literature suggests that antibiotics are likely not necessary for low-risk patients with acute uncomplicated diverticulitis, and not all patients with recurrent diverticulitis require colectomy. Dietary restrictions do not prevent recurrent diverticulitis. Visceral hypersensitivity is increasingly being recognized as a cause of persistent abdominal pain after acute diverticulitis and should be considered along with chronic smoldering diverticulitis, segmental colitis associated with diverticula, and symptomatic uncomplicated diverticular disease.

SUMMARY

Clinicians should be aware that traditionally held assumptions regarding the prevention and management of diverticular disorders have recently been called into question and should adjust their clinical practice accordingly.

Targeting Enteric Neurons and Plexitis for the Management of Inflammatory Bowel Disease

Ulcerative colitis (UC) and Crohn's disease (CD) are pathological conditions with an unknown aetiology that are characterised by severe inflammation of the intestinal tract and collectively referred to as inflammatory bowel disease (IBD). Current treatments are mostly ineffective due to their limited efficacy or toxicity, necessitating surgical resection of the affected bowel. The management of IBD is hindered by a lack of prognostic markers for clinical inflammatory relapse. Intestinal inflammation associates with the infiltration of immune cells (leukocytes) into, or surrounding the neuronal ganglia of the enteric nervous system (ENS) termed plexitis or ganglionitis. Histological observation of plexitis in unaffected intestinal regions is emerging as a vital predictive marker for IBD relapses. Plexitis associates with alterations to the structure, cellular composition, molecular expression and electrophysiological function of enteric neurons. Moreover, plexitis often occurs before the onset of gross clinical inflammation, which may indicate that plexitis can contribute to the progression of intestinal inflammation. In this review, the bilateral relationships between the ENS and inflammation are discussed. These include the effects and mechanisms of inflammation-induced enteric neuronal loss and plasticity. Additionally, the role of enteric neurons in preventing antigenic/pathogenic insult and immunomodulation is explored. While all current treatments target the inflammatory pathology of IBD, interventions that protect the ENS may offer an alternative avenue for therapeutic intervention.

Nicotine Increases Macrophage Survival through α7nAChR/NF-κB Pathway in Mycobacterium avium paratuberculosis Infection

Recently, we reported that nicotine plays a role in the failure of the macrophage in the clearance of Mycobacterium avium subspecies paratuberculosis (MAP) during infection in Crohn’s disease smokers. We also demonstrated that nicotine enhances macrophages cellular survival during MAP infection. Blocking α7 nicotinic acetylcholine receptor (α7nAChR) with the pharmacological antagonist—mecamylamine—subverted the anti-inflammatory effect of nicotine in macrophages. Yet, it is still unknown how α7nAChR is involved in the modulation of the macrophage response during MAP infection. Here, we studied the mechanistic role of nicotine-α7nAChR interaction in modulating NF-ĸB survival pathway, autophagy, and effect on cathelicidin production in MAP-infected macrophages using THP-1 cell lines. Our results showed that nicotine upregulated α7nAChR expression by 5-folds during MAP infection compared to controls. Bcl-2 expression was also significantly increased after nicotine exposure. Moreover, Nicotine inhibited autophagosome formation whereas infection with MAP in absence of nicotine has significantly increased LC-3b in macrophages. Nicotine also further upregulated NF-ĸB subunits expression including Rel-B and p100, and increased nuclear translocation of p52 protein. We also discovered that cathelicidin production was significantly suppressed in MAP-infected macrophages, treatment with nicotine showed no effect. Overall, the study provides new insight toward understanding the cellular role of nicotine through α7nAChR/NF-ĸB p100/p52 signaling pathway in inducing anti-apoptosis and macrophage survival during MAP infection in Crohn’s disease smokers.

Differences in Several Factors in the Development of Erosive Esophagitis Among Patients at Various Stages of Metabolic Syndrome: A Cross-Sectional Study

BACKGROUND

Erosive esophagitis (EE) is strongly associated with metabolic syndrome (MS), but is not always recognized in individuals with MS and the prevalence of EE in individuals with non-MS is not low.

AIM

To examine the differences in clinical factors associated with EE at various stages of MS, as well as the differences in metabolites between subjects with MS, with and without EE.

METHODS

A total of 7,097 persons who underwent health checkups including esophagogastroduodenoscopy were analyzed. We examined the differences in clinical factors for EE among subjects with non-MS, pre-MS, and MS and compared metabolites between 34 subjects with MS, with and without EE.

RESULTS

EE prevalence was significantly higher in the MS and pre-MS groups than in the non-MS group (p < 0.001). EE severity was higher in the MS group than in the pre-MS and non-MS groups (p < 0.001). In the non-MS group, there were significant differences between subjects with and without EE with respect to Helicobacter pylori (H. pylori) and smoking. In the pre-MS and MS groups, there were significant differences in H. pylori, hiatal hernia, and drinking in those with and without EE. The levels of glutamine, hypoxanthine, and lactic acid metabolites were significantly different between subjects with MS, with and without EE (all p < 0.05).

CONCLUSION

Although H. pylori and lifestyle factors such as smoking and drinking are important for EE, differences in these factors should be considered at various stages of MS. Additionally, several metabolites may be involved in the development of EE in MS.

Ebselen prevents cigarette smoke-induced gastrointestinal dysfunction in mice

Gastrointestinal (GI) dysfunction is a common comorbidity of chronic obstructive pulmonary disease (COPD) for which a major cause is cigarette smoking (CS). The underlying mechanisms and precise effects of CS on gut contractility, however, are not fully characterised. Therefore, the aim of the present study was to investigate whether CS impacts GI function and structure in a mouse model of CS-induced COPD. We also aimed to investigate GI function in the presence of ebselen, an antioxidant that has shown beneficial effects on lung inflammation resulting from CS exposure. Mice were exposed to CS for 2 or 6 months. GI structure was analysed by histology and immunofluorescence. After 2 months of CS exposure, ex vivo gut motility was analysed using video-imaging techniques to examine changes in colonic migrating motor complexes (CMMCs). CS decreased colon length in mice. Mice exposed to CS for 2 months had a higher frequency of CMMCs and a reduced resting colonic diameter but no change in enteric neuron numbers. Ten days cessation after 2 months CS reversed CMMC frequency changes but not the reduced colonic diameter phenotype. Ebselen treatment reversed the CS-induced reduction in colonic diameter. After 6 months CS, the number of myenteric nitric-oxide producing neurons was significantly reduced. This is the first evidence of colonic dysmotility in a mouse model of CS-induced COPD. Dysmotility after 2 months CS is not due to altered neuron numbers; however, prolonged CS-exposure significantly reduced enteric neuron numbers in mice. Further research is needed to assess potential therapeutic applications of ebselen in GI dysfunction in COPD.

Association of cigarette smoking with irritable bowel syndrome: A cross-sectional study

Background: Irritable Bowel Syndrome (IBS) is one of the most commonly diagnosed gastrointestinal disorders, and its etiology is believed to be multifactorial. The role of smoking in the pathophysiology of IBS still remains inconclusive. Hence, we aim to investigate whether or not an association exists between smoking and IBS. Methods: A cross-sectional study was conducted in a tertiary care hospital of Karachi. A sample size of 200 smokers and 200 non smokers was selected. A two-part self-reported questionnaire was administered to the participants and the diagnosis of IBS was based on the Rome III diagnostic criteria. All data were analyzed using the Statistical Package for the Social Sciences version 17. Statistical tests employed were Independent samples t-test, chi-square test, and binary logistic regression analysis to obtain Odds Ratio (OR) for various variables. A P-value <0.05 was considered statistically significant. Results: Overall prevalence of IBS based on Rome III criteria was 9.5% (95% CI 9.45-9.60). Smoking was significantly found to be associated with IBS (P=0.002). Binary logistic regression analysis indicated that non-smokers were more likely to have IBS (Crude OR: 3.00, 95% CI 1.23-7.30) than smokers, and females were more likely to have IBS (Crude OR: 3.73, 95% CI 1.56-7.69) than males. Age, BMI, and food groups were not found to be significantly associated with IBS. Conclusion: Our study concludes that IBS was more prevalent among non-smokers and amongst females. Further studies are required to firmly establish the role of smoking in IBS.

Epidemiology of gastroesophageal reflux disease in Iran: a systematic review and meta-analysis

BACKGROUND

Gastroesophageal reflux disease (GERD), which leads to acid reflux into the esophagus, is a common gastrointestinal disorder. Several studies have shown the prevalence of GERD in Iranian population, but their evidence is contradictory. Therefore, the present study was conducted to investigate the epidemiology of GERD in Iran.

METHODS

The entire steps of this systematic review and meta-analysis were based on the MOOSE protocol, and the results were reported accordance with the PRISMA guideline. This review is registered on PROSPERO (registration number: CRD42020142861). To find potentially relevant published articles, comprehensive search was done on international online databases Scopus, Science Direct, EMBASE, PubMed/Medline, CINAHL, EBSCO, Cochrane Library, Web of Science, Iranian online databases and the Google Scholar search engine in June 2019. Cochran test and I2 index were used to assess the heterogeneity of the studies. Data were analyzed using Comprehensive Meta-Analysis software ver. 2. The significance level of the test was considered to be P <  0.05.

RESULTS

The daily, weekly, monthly, and overall prevalence of GERD symptoms in Iranian population was 5.64% (95%CI [confidence interval]: 3.77-8.35%; N = 66,398), 12.50% (95%CI: 9.63-16.08%; N = 110,388), 18.62% (95%CI: 12.90-26.12%; N = 70,749) and 43.07% (95%CI: 35.00-51.53%; N = 73,189), respectively. The daily, weekly, monthly, and overall prevalence of heartburn in Iranian population was 2.46% (95%CI: 0.93-6.39%; N = 18,774), 9.52% (95%CI: 6.16-14.41%; N = 54,125), 8.19% (95%CI: 2.42-24.30%; N = 19,363) and 23.20% (95%CI: 13.56-36.79%; N = 26,543), respectively. The daily, weekly, monthly, and overall prevalence of regurgitation in Iranian population was 4.00% (95%CI: 1.88-8.32%; N = 18,774), 9.79% (95%CI: 5.99-15.60%; N = 41,140), 13.76% (95%CI: 6.18-44.31%; N = 19,363) and 36.53% (95%CI: 19.30-58.08%; N = 21,174), respectively. The sensitivity analysis for prevalence of all types GERD, heartburn and regurgitation symptoms by removing a study showed that the overall estimate is still robust.

CONCLUSION

The present meta-analysis provides comprehensive and useful information on the epidemiology of GERD in Iran for policy-makers and health care providers. This study showed a high prevalence of GERD in Iran. Therefore, effective measures on GERD-related factors such as lifestyle can be among the health policies of Iran.

Pharmacological and Therapeutic Aspects of Plants from the Genus Ferula: A Comprehensive Review

Inspired by nature, humankind has been able to attain significant achievements in the drug and food industries. Particularly, medicinal plants are a rich source of medicinal, cosmetic, sanitary, and aromatic substances. Genus Ferula from the Apiaceae family is a plant genus that possesses over 170 species, which have been carefully documented with regard to their medicinal properties. Ferula spp. affects many body organs, and their respective functions, in humans, such as the immune system, gastrointestinal tract, genitourinary, endocrine, respiratory, cardiovascular, nervous system, bone (skeleton), and teeth. In spite of the benefits, ferulosis (Ferula toxicity) is an important aspect of Ferula consumption in humans and animals. Hemorrhagic problems and infertility are important signs of ferulosis. In this review, we have described all of the effects of the active ingredients of Ferula spp. and their mechanisms of actions, when known, based on an extensive literature review. Thus, our review opens a window of the benefits of Ferula as a phyto-pharmaceutical and its therapeutic applications in pharmacy, dentistry, and medicine.

Clinical and endoscopic characteristics of eosinophilic esophagitis in Japan: a case-control study

Background

Eosinophilic esophagitis (EoE) is an allergy-associated clinicopathologic condition gaining an increasing amount of recognition in various areas of the world. While the clinical definition and characteristics may differ depending on country and region, sufficient studies have not yet been performed in Japan.

Objective

To assess the prevalence of EoE among the Japanese population and the clinical features associated with the disease.

Methods

Endoscopic data from January 2012 to October 2018 was gathered from 9 Japanese clinical institutes. EoE, defined as esophageal mucosal eosinophilia of at least 15 eosinophils per high-power field, was determined based on esophageal biopsies. Clinical and endoscopic patterns in the cases with EoE were investigated and compared with 186 age- and sex-matched controls.

Results

From 130,013 upper endoscopic examinations, 66 cases of EoE were identified (0.051%; mean age, 45.2 years [range, 7-79 years]; 45 males). Twenty-five patients (37.9%) with EoE were diagnosed by endoscopy during a medical check-up. Patients with EoE had more symptoms (69.7% vs. 10.8%, p < 0.01) such as dysphagia and food impaction, and more allergies (65.2% vs. 23.7%, p < 0.01) compared with the controls. The prevalence of atrophic gastritis was lower in EoE patients than in the controls (20.0% vs. 33.3%, p < 0.05).

Conclusion

The prevalence of EoE in the Japanese population was 0.051% which was comparable with previous reports in Japan. History of allergies and the absence of atrophic gastritis were associated with EoE.

The association between smoking and both types of microscopic colitis: A systematic review and meta-analysis

BACKGROUND AND STUDY AIMS

It has been suggested that smoking may be associated with microscopic colitis (MC) in some studies; however, there are conflicting results in the current literature with many of these studies having significant limitations. Our study aims to offer a meta-analysis evaluating the association between MC, including both its subtypes, and smoking.

PATIENTS AND METHODS

A systemic review was conducted in PUBMED, Embase, PubMed Central, and ScienceDirect databases from inception through December 2019. Effect estimates from the individual studies were extracted and combined using the random effect, generic inverse variance method of DerSimonian and Laird and a pooled odds ratio (OR) was calculated. Forest plots were generated, and publication bias was assessed for using conventional techniques.

RESULTS

Eight observation studies with a total of 1461 patients with MC were included in this study, 383 of whom were active smokers (26.2%). Current smoking was significantly associated with MC (OR 3.58, 95% CI, 2.51-5.11), lymphocytic colitis (LC) (OR 3.64, 95% CI, 2.46-5.38), and collagenous colitis (CC) (OR 4.43, 95% CI, 2.68-7.32). Gender-specific subgroup analysis showed a significant association with smoking was found for CC in men (OR 4.53, 95% CI, 1.59-12.85), CC in women (OR 3.27, 95% CI, 2.35-4.54), LC in women (OR 2.27, 95% CI, 1.27-4.06) and MC in women (OR 2.93, 95% CI, 2.09-4.10). We found no publication bias as assessed by the funnel plots and Egger's regression asymmetry test.

CONCLUSION

Our meta-analysis found a statistically significant association between smoking and both subtypes of MC.

Cannabis use disorders may protect against certain disorders of the digestive organs in people with schizophrenia but not in healthy controls

BACKGROUND

Previous studies have shown a potential for cannabis in disorders of the digestive organs. We aimed to investigate whether cannabis use disorders (CUD) would decrease the risk of incident disorders of the digestive organs, in people with schizophrenia and population controls.

METHODS

We combined nationwide Danish registers to identify 21 066 cases with schizophrenia and 176 935 sex-and-age-matched controls. Two models were analyzed for the associations between CUD and digestive disorders in time-varying Cox regressions: one adjusted for sex, year of birth, and calendar year; and one further adjusted for alcohol and other substance use disorders and parental education.

RESULTS

CUD was associated with a decreased risk of developing disorders of gut-brain interaction (e.g. irritable bowel syndrome, dyspepsia, etc.) among cases with schizophrenia (HR = 0.84, 95% CI 0.74-0.94, p = 0.003). CUD was associated with decreased risk of inflammatory bowel disease (HR = 0.70, 95% CI 0.49-0.99, p = 0.045) in the basically adjusted model, dropping just below statistical significance in the fully adjusted model (HR = 0.71, 95% CI 0.48-1.03, p = 0.07). CUD displayed a tendency toward a decreased risk of serious disorders of the digestive organs among cases with schizophrenia (HR = 0.89, 95% CI 0.77-1.02, p = 0.09) in the fully adjusted model. No associations were observed among controls.

CONCLUSIONS

In people with schizophrenia, but not in controls, CUD is associated with decreased risk of disorders of gut-brain interaction and inflammatory bowel disease, and possibly other serious disorders of the digestive organs. Our findings could lead to new targets for treatment and prevention of disorders of the digestive organs.

A causal relationship between cigarette smoking and type 2 diabetes mellitus: A Mendelian randomization study

The causality between smoking and type 2 diabetes is unclear. We conducted a two-sample Mendelian randomization study to explore the causal relationship between smoking initiation and type 2 diabetes. Summary-level data for type 2 diabetes were obtained from a meta-analysis of 32 genome-wide association studies (DIAbetes Genetics Replication And Meta-analysis consortium), which included 898 130 individuals of European ancestry. Totally, 377 single-nucleotide polymorphisms associated with smoking initiation at genome wide significance threshold (p < 5 × 10^-8) were identified from the hitherto largest genome-wide association study on smoking. The inverse-variance weighted, weighted median, MR-Egger regression, and MR-PRESSO approaches were used to analyze the data. Genetically predicted smoking initiation was associated with type 2 diabetes with an odds ratio of 1.28 (95% confidence interval, 1.20, 1.37; p = 2.35 × 10^-12). Results were consistent across sensitivity analyses and there was no evidence of horizontal pleiotropy. This study provides genetic evidence supporting a causal association between the smoking initiation and type 2 diabetes. Reducing cigarette smoking initiation can now be even more strongly recommended for type 2 diabetes prevention.

Nicotine attenuates concanavalin A-induced liver injury in mice by regulating the α7-nicotinic acetylcholine receptor in Kupffer cells

Nicotine, a potent parasympathomimetic alkaloid, manifests anti-inflammatory properties by activating nicotinic acetylcholine receptors (nAChRs). In this study, we evaluated the effects of nicotine on concanavalin A (ConA)-induced autoimmune hepatitis. Nicotine (0.5 and 1 mg/kg) was intraperitoneally administered to BALB/c mice and mice were intravenously injected with ConA (15 mg/kg) to induce hepatitis. The results showed that nicotine treatment ameliorated pathological lesions in livers and significantly suppressed the expression of pro-inflammatory cytokines in the livers. Such effects were mediated by inhibiting the nuclear factor-kappa B (NF-κB) signaling in livers. Interestingly, nicotine inhibited the ConA-induced inflammatory response in primary cultured Kupffer cells (KCs) but did not alter the proliferation of splenocytes. The protective effects of nicotine against ConA-induced hepatitis were abolished in KC-depleted mice, indicating the requirement of KCs in this process. Additionally, the expression of α7-nAChR on KCs was dramatically increased by nicotine treatment, and the protective effects of nicotine on ConA-induced liver injury were significantly suppressed by treatment with methyllycaconitine (MLA), a specific α7-nAChR antagonist. Consistently, in primary cultured KCs, the activation of NF-κB signaling was also regulated by nicotine treatment. This study suggests that nicotine increases α7-nAChR-mediated cholinergic activity in KCs resulting in decrease of ConA-induced autoimmune hepatitis through inhibiting NF-κB signaling.

Role of environmental factors in the pathogenesis of Crohn's disease: a critical review

PURPOSE

To review role of environmental factors in the pathogenesis of Crohn's disease.

METHODS

We systematically reviewed trials and systematic reviews using PubMed and Web of science databases. Here, we review the current information on the causative factors and mechanisms of CD, including smoking, exercise, diet, animal protein, breastfeeding, history of childhood infection and vaccination, oral contraceptives, and antibiotics of CD. We also highlight important knowledge gaps that need to be filled in order to advance the field of CD research.

RESULTS

Epidemiological studies have indicated the significance of environmental factors in the disease behavior and outcome of Crohn's disease (CD). There are a few recognized environmental factors, such as cigarette smoking, exercise, dietary habits, and breastfeeding, which are associated with the pathogenesis of CD. These factors are hypothesized to change the epithelial barrier function, which disturbs both the innate and adaptive immune systems and the intestinal flora. However, the effect of several risk factors, such as appendectomy and pharmaceutical use, differs across several studies, indicating the need for more rigorous research. Furthermore, few studies have examined effective interventions based on environmental factors that can improve disease outcomes. Recent studies have indicated that the pathogenesis of CD is related to environmental and genetic factors.

CONCLUSION

We review the current information on the causative factors and mechanisms of CD, including smoking, exercise, diet, animal protein, breastfeeding, history of childhood infection and vaccination, oral contraceptives, and antibiotics of CD. However, further studies are needed to understand knowledge gaps in the field of CD.

Molecular mechanisms for nicotine intoxication

Nicotine, one of the more than 4700 ingredients in tobacco smoke, is a neurotoxin and once used as pesticides in agriculture. Although its use in agriculture is prohibited in many countries, nicotine intoxication is still a problem among the workers in tobacco farms, and young children as well as adults due to the accidental or suicidal ingestions of nicotine products. Understanding the mechanism of nicotine intoxication is important not only for the prevention and treatment but also for the appropriate regulatory approaches. Here, we review pharmacokinetics of nicotine and the molecular mechanisms for acute and chronic intoxication from nicotine that might be relevant to the central and the peripheral nervous system. We include green tobacco sickness, acute intoxication from popular nicotine products, circadian rhythm changes, chronic intoxication from nicotine through prenatal nicotine exposure, newborn behaviors, and sudden infant death syndrome.

The role of alpha7 nicotinic acetylcholine receptors in inflammatory bowel disease: involvement of different cellular pathways

INTRODUCTION

Autonomic imbalance plays a pivotal role in the pathophysiology of inflammatory bowel diseases (IBD). The central nervous system (CNS) cooperates dynamically with the immune system to regulate inflammation through humoral and neural pathways. In particular, acetylcholine (Ach), the main neurotransmitter in the vagus nerve, decreases the production of pro-inflammatory cytokines through a mechanism dependent on the α7 nicotinic Ach receptors (α7nAChRs). Areas covered: Here, we review the evidence for involvement of the cholinergic anti-inflammatory pathway (CAP) in IBD. We also elaborate the role of α7nAChRs and subsequent cellular pathways in CAP. Finally, we review potential therapeutic implications of modulators of these receptors. Expert opinion: Alpha7nAChR modulators possess both cognitive improving and anti-inflammatory properties. Although, these agents demonstrated therapeutic benefits in experimental models, their efficacy has not always been translated in clinical trials. Thus, development of more specific α7nAChR ligands as well as more experimental studies and better controlled trials, especially in the field of IBD, are encouraged for a progress in this field.

Tobacco smoking and the risk of diverticular disease - a systematic review and meta-analysis of prospective studies

AIM

This systematic review and meta-analysis aimed to clarify whether tobacco smoking is associated with an increased risk of diverticular disease.

METHOD

The PubMed and Embase databases were searched for studies of smoking and diverticular disease up to 19 February 2016. Prospective studies that reported adjusted relative risk (RR) estimates and 95% confidence intervals (CIs) of diverticular disease associated with current or previous smoking were included. Summary RRs were estimated using a random effects model.

RESULTS

We identified five prospective studies which comprised 6076 cases of incident diverticular disease (diverticulosis and diverticulitis) among 385 291 participants and three studies with 1118 cases of complications related to diverticular disease (abscess or perforation) among 292 965. The summary RR for incident diverticular disease was 1.36 (95% CI 1.15-1.61, I²  = 84%, n = 4) for current smokers, 1.17 (95% CI 1.05-1.31, I²  = 49%, n = 4) for former smokers and 1.29 (95% CI 1.16-1.44, I²  = 62%, n = 5) for ever smokers. The summary RR was 1.11 (95% CI 0.99-1.25, I²  = 82%, n = 4) per 10 cigarettes per day. Although there was some indication of nonlinearity there was a dose-dependent positive association with increasing number of cigarettes smoked per day. There was some evidence that smoking also increases the risk of complications of diverticular disease, but the number of studies was small.

CONCLUSION

The current meta-analysis provides evidence that tobacco smoking is associated with an increased incidence of diverticular disease and related complications.

Factors Related to Upper Gastrointestinal Symptom Generation in 2275 Helicobacter pylori Seroprevalent Adults

BACKGROUND AND AIM

Upper gastrointestinal (UGI) symptoms are common; however, the role of Helicobacter pylori and gastric corpus atrophy in the generation of these symptoms is controversial. The aim of this study was to determine the risk factors for UGI symptoms in adults in an endemic area of H. pylori infection.

METHODS

Korean adults who completed questionnaires on the day of serum anti-H. pylori IgG and pepsinogen (PG) assays before UGI endoscopy were included. Gastric corpus atrophy was based on the criteria of a serum PG I/II ratio <3.0 and a PG I <70 ng/ml.

RESULTS

Of the 2275 included subjects, 723 (31.8%) had at least one UGI symptom. A total of 374 (16.4%) subjects had multiple symptoms without significant correlations between the symptoms (λ < 0.2). The H. pylori serology assay was positive in 1382 (60.7%) subjects, and gastric corpus atrophy was present in 291 (12.8%). Neither H. pylori seropositivity (p = 0.077) nor gastric corpus atrophy (p = 0.138) was related to the presence of UGI symptoms. Female gender and smoking were independent risk factors for heartburn and upper abdominal pain (all p < 0.001). Furthermore, female gender was the only independent risk factor for multiple UGI symptoms (p < 0.001), globus sensation (p < 0.001), early satiety (p < 0.001), epigastric soreness (p = 0.001), and chest discomfort (p = 0.003).

CONCLUSIONS

In an H. pylori seroprevalent population, female gender is the most common risk factor followed by smoking for UGI symptom generation. Neither H. pylori seropositivity nor gastric corpus atrophy is an independent risk factor for UGI symptom generation.

The Clinical Features and Predisposing Factors of Asymptomatic Erosive Esophagitis

BACKGROUND

Asymptomatic erosive esophagitis (AEE) is considered an erosive esophagitis without the typical reflux symptoms, but the clinical course and significance of AEE is still unclear.

AIM

We investigated the prevalence and predisposing factors of AEE, and tried to determine its clinical features and significance.

METHODS

Subjects, who had at least two health inspections (upper endoscopy, self-reporting questionnaire, and serum Helicobacter pylori IgG antibody test) at our center, were enrolled. The questionnaire included typical reflux symptoms, previous medical history, underlying disease, smoking, alcohol intake, and medication history. Based on the results of follow-up study, the changes in endoscopic findings and reflux symptoms were also investigated.

RESULTS

Of the 2961 patients visiting our clinic, 568 (19.2 %) were diagnosed with AEE. Age over 50 years, male sex, a body mass index over 25, current smoking, heavy drinking, negativity for H. pylori infection, and hiatal hernia were independent predisposing factors for AEE (p = 0.020, p < 0.001, p < 0.001, p = 0.013, p = 0.003, p < 0.001, p = 0.038, respectively). Within the follow-up period (mean 25 ± 9.5 months), reflux symptoms developed in 30 subjects (7.9 %), and current smoking was the only risk factor for the development of AEE symptoms (p = 0.015). On the follow-up endoscopy, erosive esophagitis disappeared in nearly half of the subjects with AEE (174, 45.6 %).

CONCLUSIONS

AEE is common, but many cases of AEE may be spontaneously cured without treatment. Although symptom development is rare, quitting smoking may be helpful as a prevention strategy.

CLINICAL TRIAL REGISTRATION NUMBER

KCT0001716.

Gastrointestinal Symptoms in HIV-Infected Patients: Female Sex and Smoking as Risk Factors in an Outpatient Cohort in Brazil

This study aimed to estimate the incidence of gastrointestinal symptoms (GIS) and associated factors in an outpatient cohort of people living with HIV/AIDS (PLWHA) followed between October 2009 and July 2011. We evaluated nausea and/or vomiting, dyspepsia, heartburn, diarrhea, constipation, and flatulence. The outcome variable was the presence of three or more GIS. Sociodemographic (sex, skin color, age, income, years of schooling), lifestyle (smoking status, alcohol consumption, physical activity level), clinical (antiretroviral therapy, time of HIV infection, CD4 lymphocyte count, viral load), and anthropometric (nutritional status and waist circumference) variables were investigated. Data on sociodemographic and lifestyle variables were collected through a pre-tested and standardized questionnaire. CD4 count was determined by flow cytometry and viral load by branched DNA (bDNA) assays for HIV-1. All variables were analyzed at a p<0.05 significance level. Among 290 patients, the incidence of three or more GIS was 28.8% (95% CI 23.17 to 33.84) and 74.48% presented at least one symptom. Female gender (IR 2.29, 95% CI 1.63 to 3.22) and smoking status (IR 1.93, 95% CI 1.30 to 2.88) were risk factors for the presence of three or more GIS after multivariate Poisson regression. A high incidence of gastrointestinal symptoms was found among PLWHA, and it was significantly associated with female sex and tobacco use. Those results reinforce the relevance of investigating the presence of GIS in PLWHA as it may affect treatment adherence.

Risk factors for primary sclerosing cholangitis

BACKGROUND & AIMS

Primary sclerosing cholangitis (PSC) is a progressive cholestatic liver disease of unknown cause, but strongly associated with inflammatory bowel disease (IBD). Potential risk factors triggering PSC have never been studied on a population level. The aim of this study was to evaluate smoking, appendectomy, family history and geographical distribution in a population-based cohort of PSC patients, as compared to IBD control patients and healthy controls (HC).

METHODS

For this case-control study 343 PSC patients, 370 IBD controls and 232 HC's living in a geographically defined area in the Netherlands filled-out a questionnaire concerning smoking, appendectomy and family history of IBD and autoimmune liver diseases.

RESULTS

Smoking was associated with a lower risk of developing PSC in PSC-ulcerative colitis (UC) patients (adjusted OR 0.21; 95% CI 0.12-0.34; P < 0.001). Comparable results were found for PSC-Crohn's disease (CD) patients (16% former smokers) compared to CD patients (55% former smokers) (adjusted OR 0.17; 95% CI 0.08-0.39; P < 0.001). Frequency of appendectomy did not differ between PSC and HC, but PSC-UC patients had undergone appendectomy more often than UC patients (13% vs. 6%) (adjusted OR 2.51; 95%CI 1.04-6.07; P = 0.041). We found no association between family history of IBD or autoimmune liver disease and risk of PSC. Degree of urbanization was not associated with PSC incidence.

CONCLUSION

In this large population-based case-control study we confirm that smoking is associated with a lower risk of developing PSC, independent of its protective effect for developing UC. Appendectomy is not associated with the risk of developing PSC.

Arrhythmogenic Risk Assessment Following Four-Week Pretreatment With Nicotine and Black Tea in Rat

BACKGROUND

There is the controversy concerning the main component of tobacco, which is responsible for its arrhythmogenesis. In addition, there is the lack of adequate information about the influence of combination of black tea and nicotine on heart rhythm.

OBJECTIVES

This study aimed to examine whether pretreatment with black tea and nicotine could modulate the susceptibility to lethal ventricular arrhythmias.

MATERIALS AND METHODS

Animals were randomized to control, black tea, nicotine, and black tea plus nicotine groups. Test groups were treated with black tea brewed (orally) and nicotine (2 mg/kg, subcutaneous), alone and in combination for four weeks. On day 29, aconitine was infused intravenously for induction of cardiac arrhythmia.

RESULTS

In comparison with the control group, each of tea and nicotine significantly decreased the duration of the ventricular tachycardia (VT) plus ventricular fibrillation (VF) and the score of arrhythmia severity (P < 0.05 and P < 0.01, respectively,). The latency for the first VT event was significantly longer in the all test groups, but VF latency was significant only in tea and nicotine groups compared with control group (P < 0.05 and P < 0.01, respectively).Threshold dose of aconitine for inducing VT and VF increased in all test groups, but only VT showed a significant difference in comparison to the control group (P < 0.001).

CONCLUSIONS

The findings suggest that sub-chronic consumption of nicotine or black tea alone with appropriate doses could potentially be antiarrhythmic and its combination regimen does not increase the risk of fatal ventricular arrhythmias during four-week consumption period in rats.

Smoking status and prevalence of upper gastrointestinal disorders

BACKGROUND

Lifestyle and environmental factors affecting upper gastrointestinal (GI) disorders are different in developing countries than those in developed nations.

OBJECTIVE

This study aimed to examine the association between smoking status and upper GI disorders among a large group of the Iranian adult population.

METHODS

This cross-sectional study was conducted among 1,933 adult men in Isfahan, Iran. Smoking status was assessed by a self-administered questionnaire. Required information on GI health was collected through the use of the validated ROME III questionnaire. Individuals who reported having heartburn sometimes, often, or always in the last 3 months were considered as having epidemiologic gastroesophageal reflux disease (GERD), and those who reported having heartburn often or always were considered as having clinical GERD. Subjects who reported having functional dyspepsia (FD) symptoms (based on the ROME III criteria) sometimes, often, or always in the last 3 months were considered as having epidemiologic FD, and those who reported having these disorders often or always were considered as having clinical FD.

RESULTS

Smoking was prevalent among 7.8% of the study population. FD and GERD was prevalent among 12.6% (n = 244) and 22.3% (n = 432), respectively. Smoking was not associated with GERD by either the epidemiologic or clinical definition. Although the association between smoking and FD (epidemiologic definition) was not statistically significant, smokers had an 83% higher risk of suffering from clinical FD compared with nonsmokers after taking potential confounders into account [odds ratio (OR) = 1.83, 95% CI: 1.12-3.00; p = 0.01]. Smokers had a 57% higher risk for epidemiologic postprandial fullness (OR = 1.57, 95% CI: 1.05-2.33; p = 0.02) and a 92% higher risk for clinical epigastric pain compared with nonsmokers (OR = 1.92, 95% CI: 1.02-3.62; p = 0.04). We found no significant association between smoking and severity of upper GI disorders.

CONCLUSION

This large population-based study indicated that smoking was not associated with GERD and epidemiologic FD. However, smoking was significantly associated with clinical FD, postprandial fullness, and epigastric pain.

Association of MMP7 -181A→G Promoter Polymorphism with Gastric Cancer Risk: INFLUENCE OF NICOTINE IN DIFFERENTIAL ALLELE-SPECIFIC TRANSCRIPTION VIA INCREASED PHOSPHORYLATION OF cAMP-RESPONSE ELEMENT-BINDING PROTEIN (CREB)

Elevated expression of matrix metalloproteinase7 (MMP7) has been demonstrated to play a pivotal role in cancer invasion. The -181A→G (rs11568818) polymorphism in the MMP7 promoter modulates gene expression and possibly affects cancer progression. Here, we evaluated the impact of -181A→G polymorphism on MMP7 promoter activity and its association with gastric cancer risk in eastern Indian case-control cohorts (n = 520). The GG genotype as compared with the AA genotype was predisposed (p = 0.02; odds ratio = 1.9, 95% confidence interval = 1.1-3.3) to gastric cancer risk. Stratification analysis showed that tobacco addiction enhanced gastric cancer risk in GG subjects when compared with AA subjects (p = 0.03, odds ratio = 2.46, and 95% confidence interval = 1.07-5.68). Meta-analysis revealed that tobacco enhanced the risk for cancer more markedly in AG and GG carriers. Activity and expression of MMP7 were significantly higher in GG than in AA carriers. In support, MMP7 promoter-reporter assays showed greater transcriptional activity toward A to G transition under basal/nicotine-induced/cAMP-response element-binding protein (CREB) overexpressed conditions in gastric adenocarcinoma cells. Moreover, nicotine (a major component of tobacco) treatment significantly up-regulated MMP7 expression due to enhanced CREB phosphorylation followed by its nuclear translocation in gastric adenocarcinoma cells. Furthermore, chromatin immunoprecipitation experiments revealed higher binding of phosphorylated CREB with the -181G than the -181A allele. Altogether, specific binding of phosphorylated CREB to the G allele-carrying promoter enhances MMP7 gene expression that is further augmented by nicotine due to increased CREB phosphorylation and thereby increases the risk for gastric cancer.

Anti-inflammatory effects of the nicotinergic peptides SLURP-1 and SLURP-2 on human intestinal epithelial cells and immunocytes

A search for novel and more efficient therapeutic modalities of inflammatory bowel disease (IBD) is one of the most important tasks of contemporary medicine. The anti-inflammatory action of nicotine in IBD might be therapeutic, but its toxicity due to off-target and nonreceptor effects limited its use and prompted a search for nontoxic nicotinergic drugs. We tested the hypothesis that SLURP-1 and -2—the physiological nicotinergic substances produced by the human intestinal epithelial cells (IEC) and immunocytes—can mimic the anti-inflammatory effects of nicotine. We used human CCL-241 enterocytes, CCL-248 colonocytes, CCRF-CEM T-cells, and U937 macrophages. SLURP-1 diminished the TLR9-dependent secretion of IL-8 by CCL-241, and IFNγ-induced upregulation of ICAM-1 in both IEC types. rSLURP-2 inhibited IL-1β-induced secretion of IL-6 and TLR4- and TLR9-dependent induction of CXCL10 and IL-8, respectively, in CCL-241. rSLURP-1 decreased production of TNFα by T-cells, downregulated IL-1β and IL-6 secretion by macrophages, and moderately upregulated IL-10 production by both types of immunocytes. SLURP-2 downregulated TNFα and IFNγR in T-cells and reduced IL-6 production by macrophages. Combining both SLURPs amplified their anti-inflammatory effects. Learning the pharmacology of SLURP-1 and -2 actions on enterocytes, colonocytes, T cells, and macrophages may help develop novel effective treatments of IBD.

Determinants of gastroesophageal reflux disease, including hookah smoking and opium use- a cross-sectional analysis of 50,000 individuals

BACKGROUND

Gastroesophageal reflux disease (GERD) is a common cause of discomfort and morbidity worldwide. However, information on determinants of GERD from large-scale studies in low- to medium-income countries is limited. We investigated the factors associated with different measures of GERD symptoms, including frequency, patient-perceived severity, and onset time.

METHODS

We performed a cross-sectional analysis of the baseline data from a population-based cohort study of ∼ 50,000 individuals in in Golestan Province, Iran. GERD symptoms in this study included regurgitation and/or heartburn.

RESULTS

Approximately 20% of participants reported at least weekly symptoms. Daily symptoms were less commonly reported by men, those of Turkmen ethnicity, and nass chewers. On the other hand, age, body mass index, alcohol drinking, cigarette smoking, opium use, lower socioeconomic status, and lower physical activity were associated with daily symptoms. Most of these factors showed similar associations with severe symptoms. Women with higher BMI and waist to hip ratio were more likely to report frequent and severe GERD symptoms. Hookah smoking (OR 1.34, 95% CI 1.02-1.75) and opium use (OR 1.70, 95% CI 1.55-1.87) were associated with severe symptoms, whereas nass chewing had an inverse association (OR 0.87, 95% CI 0.76-0.99). After exclusion of cigarette smokers, hookah smoking was still positively associated and nass chewing was inversely associated with GERD symptoms (all frequencies combined).

CONCLUSION

GERD is common in this population. The associations of hookah and opium use and inverse association of nass use with GERD symptoms are reported for the first time. Further studies are required to investigate the nature of these associations. Other determinants of GERD were mostly comparable to those reported elsewhere.

Constipation and a low-fiber diet are not associated with diverticulosis

BACKGROUND & AIMS

Asymptomatic diverticulosis is commonly attributed to constipation caused by a low-fiber diet, although evidence for this mechanism is limited. We examined the associations between constipation and low dietary fiber intake with risk of asymptomatic diverticulosis.

METHODS

We performed a cross-sectional study that analyzed data from 539 individuals with diverticulosis and 1569 without (controls). Participants underwent colonoscopy and assessment of diet, physical activity, and bowel habits. Our analysis was limited to participants with no knowledge of their diverticular disease to reduce the risk of biased responses.

RESULTS

Constipation was not associated with an increased risk of diverticulosis. Participants with less frequent bowel movements (<7/wk) had reduced odds of diverticulosis compared with those with regular bowel movements (7/wk) (odds ratio [OR], 0.56; 95% confidence interval [CI], 0.40-0.80). Those reporting hard stools also had reduced odds (OR, 0.75; 95% CI, 0.55-1.02). There was no association between diverticulosis and straining (OR, 0.85; 95% CI, 0.59-1.22) or incomplete bowel movement (OR, 0.85; 95% CI, 0.61-1.20). We found no association between dietary fiber intake and diverticulosis (OR, 0.96; 95% CI, 0.71-1.30) in comparing the highest quartile with the lowest (mean intake, 25 vs 8 g/day).

CONCLUSIONS

In our cross-sectional, colonoscopy-based study, neither constipation nor a low-fiber diet was associated with an increased risk of diverticulosis.

Impact of current smoking on the clinical course of microscopic colitis

BACKGROUND

Whether current smoking worsens the clinical course of microscopic colitis (MC) is unknown. The aim was to evaluate the impact of smoking on the clinical course of MC.

METHODS

One hundred and eighty-four patients (72% women; age, 62.4 ± 1.1 years) with MC (118 collagenous colitis (CC) and 66 lymphocytic colitis (LC) were evaluated (39 of them were current smokers). In all the patients, smoking habits and clinical data at presentation, response to therapy, and clinical relapses during follow-up were prospectively recorded. Risk factors for clinical relapse were studied in 160 patients after a mean follow-up of 28 ± 1 months. Cox regression analysis was used to adjust for confounding variables.

RESULTS

Age at diarrhea onset was 63.0 ± 1.4 years in nonsmokers and 50.4 ± 2.1 years in current smokers (P < 0.001). There was no significant influence of smoking habit on either clinical symptoms at diagnosis or clinical remission rate. Clinical relapse rate was 25.5% for CC and 29.6% for LC, with the mean relapse-free time 28.8 months (95% confidence interval, 26.3-31.4) for CC and 26.9 months (95% confidence interval, 26-30.3) for LC (P = 0.5). Multivariate analysis showed that age at diagnosis (<50 years versus others; adjusted hazard ratio, 2.8; 95% confidence interval, 1.3-6; P = 0.01) was associated with risk of relapse of CC but not LC. Current smoking was not an independent risk factor for either CC or LC relapse.

CONCLUSIONS

Active smokers developed MC more than a decade before nonsmokers. Age at diagnosis, but not smoking, was an independent risk factor of relapse in patients with CC.

Lifestyle factors associated with gastroesophageal reflux disease in the Japanese population

BACKGROUND

We aimed to clarify the lifestyle factors associated with erosive esophagitis and non-erosive reflux disease (NERD) in a Japanese population.

METHODS

Among 886 subjects who underwent health screening, we selected, according to their scores on the FSSG (frequency scale for symptoms of gastroesophageal reflux disease; GERD) questionnaire and the findings of upper gastrointestinal endoscopy, 138 subjects with erosive esophagitis (EE), 148 subjects with NERD (absence of esophagitis, FSSG score ≥8, and acid reflux-related symptoms score ≥4), and 565 control subjects (absence of esophagitis and FSSG score ≤7). We compared clinical characteristics and various lifestyle factors in these three groups.

RESULTS

The lifestyle factors significantly associated with NERD compared with findings in the control group were intake of egg (odds ratio [OR] 1.89, 95% confidence interval [CI] 1.01-3.50), sleep shortage (OR 2.44, 95% CI 1.54-3.88), and strong psychological stress (OR 1.77, 95% CI 1.18-2.62). In male subjects, current smoking (OR 2.06, 95% CI 1.13-3.74; OR 1.87, 95% CI 1.09-3.20) was a significant risk factor for both NERD and EE. Moreover, alcohol >200 kcal/day (OR 3.99, 95% CI 1.03-15.55) and intake of a large quantity of food at supper (OR 7.85, 95% CI 1.66-37.05) were significant risk factors for EE in subjects with hiatal hernia. Intake of a large quantity of food at supper (OR 2.09, 95% CI 1.06-4.13) was more common in the NERD group than in the EE group.

CONCLUSIONS

There were differences in the associated lifestyle factors between patients with NERD and those with EE, and there was also a gender-related difference between these groups.

Functional dyspepsia: subtypes, risk factors, and overlap with irritable bowel syndrome in a population of african patients

Background. Functional dyspepsia is the prototype functional gastrointestinal disorder. This study was designed to determine its prevalence, subtypes, and risk factors associated with the subtypes. Method. Patients with upper gastrointestinal symptoms who presented for endoscopy were administered a questionnaire containing the functional dyspepsia and irritable bowel syndrome modules of the Rome III diagnostic criteria. Results. Of 192 patients who had functional dyspepsia, epigastric pain syndrome, postprandial distress syndrome, and combination of the two subtypes accounted for 79.2%, 62.5%, and 50%, respectively. Multivariate analysis of the risk factors showed that independent predictors of postprandial distress syndrome were alcohol and irritable bowel syndrome while irritable bowel syndrome was independent predictor of epigastric pain syndrome. Alcohol, smoking, and use of nonsteroidal anti-inflammatory drugs were independent predictors of cooccurrence of postprandial distress syndrome and epigastric pain syndrome. Conclusion. Functional dyspepsia accounts for 62.5% of dyspepsia in a population of black African patients. Regarding symptomatology, epigastric pain syndrome, postprandial distress syndrome, and combination of the two subtypes account for 79.2%, 62.5%, and 50%, respectively. Risk factors for functional dyspepsia are irritable bowel syndrome, alcohol, smoking, and use of nonsteroidal anti-inflammatory drugs.

A prospective study of cigarette smoking and the risk of inflammatory bowel disease in women

OBJECTIVES

Long-term data on the influence of cigarette smoking, especially cessation, on the risk of Crohn's disease (CD) and ulcerative colitis (UC) are limited.

METHODS

We conducted a prospective study of 229,111 women in the Nurses' Health Study (NHS) and Nurses' Health Study II (NHS II). Biennially, we collected updated data on cigarette smoking, other risk factors, and diagnoses of CD or UC confirmed by medical record review.

RESULTS

Over 32 years in NHS and 18 years in NHS II, we documented 336 incident cases of CD and 400 incident cases of UC. Compared with never smokers, the multivariate hazard ratio (HR) of CD was 1.90 (95% confidence interval (CI), 1.42-2.53) among current smokers and 1.35 (95% CI, 1.05-1.73) among former smokers. Increasing pack-years was associated with increasing risk of CD (Ptrend < 0.0001), whereas smoking cessation was associated with an attenuation of risk. By contrast, the multivariate HR of UC was 0.86 (95% CI, 0.61-1.20) among current smokers and 1.56 (95% CI, 1.26-1.93) among former smokers. The risk of UC was significantly increased within 2-5 years of smoking cessation (HR, 3.06; 95% CI, 2.00-4.67) and remained persistently elevated over 20 years.

CONCLUSIONS

Current smoking is associated with an increased risk of CD, but not UC. By contrast, former smoking is associated with an increased risk of UC, with risk persisting over two decades after cessation.

Smoking and the skin

Cigarette smoking has been associated with significant morbidity affecting all systems of the body, including the integumentary system. We review the many dermatologic hazards of tobacco use. It is important to distinguish between the effects of tobacco smoke from effects of pure nicotine on the skin. All skin cells express several subtypes of the nicotinic class of acetylcholine receptors, including the α7 receptor. Many chronic dermatoses are affected by smoking either negatively or positively. Elucidation of positive associations with a particular disease can lead to improvement from smoking cessation, whereas inverse correlation may lead to development of a disease-specific treatment with nicotinergic agonists.

Novel information on the non-neuronal cholinergic system in orthopedics provides new possible treatment strategies for inflammatory and degenerative diseases

Anti-cholinergic agents are used in the treatment of several pathological conditions. Therapy regimens aimed at up-regulating cholinergic functions, such as treatment with acetylcholinesterase inhibitors, are also currently prescribed. It is now known that not only is there a neuronal cholinergic system but also a non-neuronal cholinergic system in various parts of the body. Therefore, interference with the effects of acetylcholine (ACh) brought about by the local production and release of ACh should also be considered. Locally produced ACh may have proliferative, angiogenic, wound-healing, and immunomodulatory functions. Interestingly, cholinergic stimulation may lead to anti-inflammatory effects. Within this review, new findings for the locomotor system of a more widespread non-neuronal cholinergic system than previously expected will be discussed in relation to possible new treatment strategies. The conditions discussed are painful and degenerative tendon disease (tendinopathy/tendinosis), rheumatoid arthritis, and osteoarthritis.

Cannabis use amongst patients with inflammatory bowel disease

BACKGROUND

Experimental evidence suggests the endogenous cannabinoid system may protect against colonic inflammation, leading to the possibility that activation of this system may have a therapeutic role in inflammatory bowel disease (IBD). Medicinal use of cannabis for chronic pain and other symptoms has been reported in a number of medical conditions. We aimed to evaluate cannabis use in patients with IBD.

METHODS

One hundred patients with ulcerative colitis (UC) and 191 patients with Crohn's disease (CD) attending a tertiary-care outpatient clinic completed a questionnaire regarding current and previous cannabis use, socioeconomic factors, disease history and medication use, including complimentary alternative medicines. Quality of life was assessed using the short-inflammatory bowel disease questionnaire.

RESULTS

A comparable proportion of UC and CD patients reported lifetime [48/95 (51%) UC vs. 91/189 (48%) CD] or current [11/95 (12%) UC vs. 30/189 (16%) CD] cannabis use. Of lifetime users, 14/43 (33%) UC and 40/80 (50%) CD patients have used it to relieve IBD-related symptoms, including abdominal pain, diarrhoea and reduced appetite. Patients were more likely to use cannabis for symptom relief if they had a history of abdominal surgery [29/48 (60%) vs. 24/74 (32%); P=0.002], chronic analgesic use [29/41 (71%) vs. 25/81 (31%); P<0.001], complimentary alternative medicine use [36/66 (55%) vs. 18/56 (32%); P=0.01] and a lower short inflammatory bowel disease questionnaire score (45.1±2.1 vs. 50.3±1.5; P=0.03). Patients who had used cannabis [60/139 (43%)] were more likely than nonusers [13/133 (10%); P<0.001 vs. users] to express an interest in participating in a hypothetical therapeutic trial of cannabis for IBD.

CONCLUSION

Cannabis use is common amongst patients with IBD for symptom relief, particularly amongst those with a history of abdominal surgery, chronic abdominal pain and/or a low quality of life index. The therapeutic benefits of cannabinoid derivatives in IBD may warrant further exploration.

Cigarette smoke extract (CSE) delays NOD2 expression and affects NOD2/RIPK2 interactions in intestinal epithelial cells

BACKGROUND

Genetic and environmental factors influence susceptibility to Crohn's disease (CD): NOD2 is the strongest individual genetic determinant and smoking the best-characterised environmental factor. Carriage of NOD2 mutations predispose to small-intestinal, stricturing CD, a phenotype also associated with smoking. We hypothesised that cigarette smoke extract (CSE) altered NOD2 expression and function in intestinal epithelial cells.

METHODS AND FINDINGS

Intestinal epithelial cell-lines (SW480, HT29, HCT116) were stimulated with CSE and nicotine (to mimic smoking) ±TNFα (to mimic inflammation). NOD2 expression was measured by qRT-PCR and western blotting; NOD2-RIPK2 interactions by co-immunoprecipitation (CoIP); nuclear NFκB-p65 by ELISA; NFκB activity by luciferase reporter assays and chemokines (CCL20, IL8) in culture supernatants by ELISA. In SW480 and HT29 cells the TNFα-induced NOD2 expression at 4 hours was reduced by CSE (p = 0.0226), a response that was dose-dependent (p = 0.003) and time-dependent (p = 0.0004). Similar effects of CSE on NOD2 expression were seen in cultured ileal biopsies from healthy individuals. In SW480 cells CSE reduced TNFα-induced NFκB-p65 translocation at 15 minutes post-stimulation, upstream of NOD2. Levels of the NOD2-RIPK2 complex were no different at 8 hours post-stimulation with combinations of CSE, nicotine and TNFα, but at 18 hours it was increased in cells stimulated with TNFα+CSE but decreased with TNFα alone (p = 0.0330); CSE reduced TNFα-induced NFκB activity (p = 0.0014) at the same time-point. At 24 hours, basal CCL20 and IL8 (p<0.001 for both) and TNFα-induced CCL20 (p = 0.0330) production were decreased by CSE. CSE also reduced NOD2 expression, CCL20 and IL8 production seen with MDP-stimulation of SW480 cells pre-treated with combinations of TNFα and CSE.

CONCLUSIONS

CSE delayed TNFα-induced NOD2 mRNA expression and was associated with abnormal NOD2/RIPK2 interaction, reduced NFκB activity and decreased chemokine production. These effects may be involved in the pathogenesis of small-intestinal CD and may have wider implications for the effects of smoking in NOD2-mediated responses.