Nicotine enemas for active Crohn's colitis: an open pilot study

Concomitant 5-aminosalicylic acid treatment does not affect 6-thioguanine nucleotide levels in patients with inflammatory bowel disease on thiopurines

Background

There are conflicting data as to whether co-treatment with 5-aminosalicylic acid (5-ASA) in patients with inflammatory bowel disease (IBD) under azathioprine (AZA) or 6-mercaptopurine (6-MP) therapy may influence 6-thioguanine nucleotide (6-TGN) concentrations, and whether this combination puts patients at risk of side-effects. The aim of the study was to determine 6-TGN levels in patients treated with AZA/6-MP, either alone or in combination with 5-ASA.

Methods

Available blood samples from patients treated with AZA or 6-MP were retrieved from the Swiss IBD Cohort Study (SIBDCS). The eligible individuals were divided into 2 groups: those with vs. without 5-ASA co-medication. Levels of 6-TGN and 6-methylmercaptopurine ribonucleotides (6-MMPR) were determined and compared. Potential confounders were compared between the groups, and also evaluated as potential predictors for a multivariate regression model.

Results

Of the 110 patients enrolled in this analysis, 40 received concomitant 5-ASA at the time of blood sampling. The median 6-TGN levels in patients with vs. those without 5-ASA co-treatment were 261 and 257 pmol/8×108 erythrocytes, respectively (P=0.97). Likewise, there were no significant differences in 6-MMPR levels (P=0.79). Through multivariate analysis, 6-TGN levels were found to be significantly higher in non-smokers, patients without prior surgery, and those without signs of stress-hyperarousal.

Conclusions

Blood concentrations of 6-TGN and 6-MMPR did not differ between patients with vs. those without 5-ASA co-treatment. Our data warrant neither more frequent lab monitoring nor dose adaptation of AZA in patients receiving concomitant 5-ASA treatment.

Effect of Nicotine on Immune System Function

As a parasympathetic alkaloid and the main substance in cigarette smoke, nicotine modulates the immune system, inhibits innate and acquired immunity and is used in treating many autoimmune diseases. It often stimulates the α7 receptor and causes an anti-inflammatory state in the body. This study is designed to evaluate the role of nicotine treatment on immune system. The results showed that nicotine affects many cells in immune system, alters the downstream intracellular mechanisms and changes lymphocytes polarization. This substance alters TLRs and STATs gene expression and thus changes in the innate immune system. All these events inhibit the secretion of pro-inflammatory cytokines and chemokines which increase angiogenesis and metastasis and exacerbates tumors due to increasing survival and cell growth. Nicotine can aggravate tumors in cancer patients, with many positive effects observed in the treating autoimmune disease, Nicotine treatment function in different conditions depends on factors such as concentration, how it is employed, treatment duration and other conditions such as body conditions affecting the immune system, hence, further studies and review of all conditions are required.

A Pilot Randomized Trial of Transdermal Nicotine for Pulmonary Sarcoidosis

BACKGROUND

Tobacco smoking is associated with a reduced risk of developing sarcoidosis, and we previously reported that nicotine normalizes immune responses to environmental antigens in patients with active pulmonary sarcoidosis. The effects of nicotine on the progression of pulmonary sarcoidosis are unknown.

RESEARCH QUESTION

Is nicotine treatment well tolerated, and will it improve lung function in patients with active pulmonary sarcoidosis?

STUDY DESIGN AND METHODS

With local institutional review board approval, a randomized, double-blind, controlled pilot trial was conducted of daily nicotine transdermal patch treatment (21 mg daily) or placebo patch use for 24 weeks. The Ohio State University Wexner Medical Center and Cleveland Clinic enrolled 50 consecutive adult subjects aged ≥ 18 years with active pulmonary sarcoidosis, based on symptoms (ie, dyspnea, cough) and objective radiographic evidence of infiltrates consistent with nonfibrotic lung disease. Each study group was compared at 26 weeks based on repeated measures of FVC, FEV₁, quantitative lung texture score based on CT texture analysis, Fatigue Assessment Score (FAS), St. George's Respiratory Questionnaire (SGRQ), and the Sarcoidosis Assessment Tool.

RESULTS

Nicotine treatment was associated with a clinically significant, approximately 2.1% (70 mL) improvement in FVC from baseline to 26 weeks. FVC decreased by a similar amount (2.2%) in the placebo group, with a net increase of 140 mL (95% CI, 10-260) when comparing nicotine vs placebo groups at 26 weeks. FEV₁ and FAS improved marginally in the nicotine-treated group, compared with those on placebo. No improvement was observed in lung texture score, FAS, St. George's Respiratory Questionnaire score, or the Sarcoidosis Assessment Tool. There were no reported serious adverse events or evidence of nicotine addiction.

INTERPRETATION

Nicotine treatment was well tolerated in patients with active pulmonary sarcoidosis, and the preliminary findings of this pilot study suggest that it may reduce disease progression, based on FVC.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT02265874; URL: www.clinicaltrials.gov.

Baroreceptor Modulation of the Cardiovascular System, Pain, Consciousness, and Cognition

Baroreceptors are mechanosensitive elements of the peripheral nervous system that maintain cardiovascular homeostasis by coordinating the responses to external and internal environmental stressors. While it is well known that carotid and cardiopulmonary baroreceptors modulate sympathetic vasomotor and parasympathetic cardiac neural autonomic drive, to avoid excessive fluctuations in vascular tone and maintain intravascular volume, there is increasing recognition that baroreceptors also modulate a wide range of non-cardiovascular physiological responses via projections from the nucleus of the solitary tract to regions of the central nervous system, including the spinal cord. These projections regulate pain perception, sleep, consciousness, and cognition. In this article, we summarize the physiology of baroreceptor pathways and responses to baroreceptor activation with an emphasis on the mechanisms influencing cardiovascular function, pain perception, consciousness, and cognition. Understanding baroreceptor-mediated effects on cardiac and extra-cardiac autonomic activities will further our understanding of the pathophysiology of multiple common clinical conditions, such as chronic pain, disorders of consciousness (e.g., abnormalities in sleep-wake), and cognitive impairment, which may result in the identification and implementation of novel treatment modalities. © 2021 American Physiological Society. Compr Physiol 11:1373-1423, 2021.

Design, rationale, and baseline characteristics of a pilot randomized clinical trial of nicotine treatment for pulmonary sarcoidosis

Introduction

Sarcoidosis is a systemic granulomatous disease of unknown cause afflicting young to middle-aged adults. The majority of patients with active pulmonary sarcoidosis complain of overwhelming fatigue, which often persists despite administration of immune-modulating drugs typically used to treat sarcoidosis. Nicotine offers an alternative to conventional treatments, which are associated with a spectrum of serious untoward effects, including diabetes mellitus, osteoporosis, bone marrow suppression, severe infections, cirrhosis. The described pilot randomized trial aims to provide preliminary data required to design subsequent Phase II/III trials to formally evaluate nicotine as a novel low-cost and highly-effective, safe treatment option for patients with active pulmonary sarcoidosis.

Methods

and Design: This is a randomized double-blind controlled trial of adults with confirmed pulmonary sarcoidosis, allocated in equal proportion to sustained release transdermal nicotine or placebo patch. The primary objective outcome is the improvement in forced vital capacity at study week 26 from baseline measurement. Secondary measures include lung texture score, and self-reported outcomes including the Fatigue Assessment Scale, the St George's Respiratory Questionnaire, and the Sarcoidosis Assessment Tool.

Discussion

Current therapies for active pulmonary sarcoidosis, remain either expensive and often with numerous side-effects, as with novel industry developed therapies, or with reduced quality of life, as with corticosteroids. Nicotine therapy provides promise as a safe, available, and cost-effective intervention strategy, which we expect to be acceptable to patients.

ClinicalTrials.gov

NCT02265874.

Nicotine and autoimmunity: The lotus' flower in tobacco

Nicotine, the major component of cigarettes, has demonstrated conflicting impact on the immune system: some authors suggest that increases pro-inflammatory cytokines and provokes cellular apoptosis of neutrophils, releasing intracellular components that act as auto-antigens; others claimed that nicotine has a protective and anti-inflammatory effects, especially by binding to α7 subunit of nicotinic acetylcholine receptors. The cholinergic pathway contributes to an anti-inflammatory environment characterized by increasing T regulatory cells response, down-regulating of pro-inflammatory cytokines and a pro-inflammatory cells apoptosis. The effects of nicotine were studied in different autoimmune disease, as multiple sclerosis, type 1 diabetes, rheumatoid arthritis, sarcoidosis, Behçet's disease and inflammatory bowel diseases. The major problems about nicotine are the addiction and the adverse effects of related to each commercialized formulation. We sought in this review to summarize the knowledge accumulated to date concerning the relationship between nicotine and autoimmunity.

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.

Nicotine treatment improves Toll-like receptor 2 and Toll-like receptor 9 responsiveness in active pulmonary sarcoidosis

BACKGROUND

New evidence links nicotine to the regulation of T cell-mediated inflammation via a 7 nicotinic cholinergic receptor activation, and chronic nicotine exposure (smoking) reduces the incidence of granulomatous diseases. We sought to determine whether nicotine treatment was well tolerated while effectively normalizing immune responses in patients with active pulmonary sarcoidosis.

METHODS

Consenting adults with symptomatic sarcoidosis (n 5 13) were randomly assigned to receive 12 weeks of nicotine treatment plus conventional therapy or conventional therapy alone. Obtained blood cells were evaluated for their responsiveness to selected Toll-like receptor (TLR) and nucleotide oligomerization domain-like receptor ligands and T cell surface marker expression before and after nicotine treatment. Asymptomatic patients (n 5 6) and disease-free subjects (n 5 6) served as comparative control subjects. Adverse events were monitored for the duration of the study.

RESULTS

Compared with the asymptomatic group, symptomatic patients had impaired peripheral responses to TLR2, TLR4, and TLR9 ligands (anergy) and reduced peripheral populations of CD4 1 FoxP3 1 regulatory T cells (Tregs). Nicotine treatment was associated with restoration of TLR2 and TLR9 responsiveness, and expansion of Tregs, including the CD4 1 CD25 2 FoxP3 1 phenotype. There were no serious adverse events or signs of nicotine dependency.

CONCLUSIONS

Nicotine treatment in active pulmonary sarcoidosis was well tolerated and restored peripheral immune responsiveness to TLR2 and TLR9 agonists and expansion of FoxP3 1 Tregs, including a specific “preactivated” (CD25 2 ) phenotype. The immune phenotype of patients with symptomatic sarcoidosis treated with nicotine closely resembled that of asymptomatic patients, supporting the notion that nicotine treatment may be beneficial in this patient population.

The effect of smoking on intestinal inflammation: what can be learned from animal models?

Epidemiological evidence demonstrates that smoking is the most important environmental risk factor in Crohn's disease while it positively interferes with the disease course of ulcerative colitis. However, the underlying mechanisms through which smoking exerts this divergent effect and affects pathogenesis of inflammatory bowel disease are largely unknown. Animal smoke models are good models to investigate the impact of cigarette smoke on intestinal physiology and inflammation. They enable one to explore the interaction of smoke components and the gut on cellular and molecular level, clarifying how smoking interferes with normal gut function and with disease course in inflammatory conditions. This review describes the currently used animal models for studying the impact of cigarette smoke on the intestinal tract. We first discuss the different methods for simulation of smoking. Furthermore, we focus on the effect of smoke exposure on normal gut physiology and immunology, on experimental (entero)colitis, and on inflammation-induced neoplasia. Based on this current knowledge, a hypothesis is formulated about the mechanisms through which cigarette smoke interferes with the gut in normal and pathological conditions.

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.

Ulcerative colitis and Crohn's disease: is Mycobacterium avium subspecies paratuberculosis the common villain?

Mycobacterium avium, subspecies paratuberculosis (MAP) causes a chronic disease of the intestines in dairy cows and a wide range of other animals, including nonhuman primates, called Johne's ("Yo-knee's") disease. MAP has been consistently identified by a variety of techniques in humans with Crohn's disease. The research investigating the presence of MAP in patients with Crohn's disease has often identified MAP in the "negative" ulcerative colitis controls as well, suggesting that ulcerative colitis is also caused by MAP. Like other infectious diseases, dose, route of infection, age, sex and genes influence whether an individual infected with MAP develops ulcerative colitis or Crohn's disease. The apparently opposite role of smoking, increasing the risk of Crohn's disease while decreasing the risk of ulcerative colitis, is explained by a more careful review of the literature that reveals smoking causes an increase in both diseases but switches the phenotype from ulcerative colitis to Crohn's disease. MAP as the sole etiologic agent of both ulcerative colitis and Crohn's disease explains their common epidemiology, geographic distribution and familial and sporadic clusters, providing a unified hypothesis for the prevention and cure of the no longer "idiopathic" inflammatory bowel diseases.

The impact of smoking in Crohn's disease: no smoke without fire

Smoking habit is the most widely accepted environmental factor affecting the incidence and disease progression in the inflammatory bowel diseases. The contrasting effects in Crohn's disease (CD) and ulcerative colitis are unexplained. The purpose of this review is to summarise the existing data on the effects of smoking in CD on disease history, recurrence after surgery, effects on drug responses and to review available evidence that carriage of some of the known susceptibility genes may be disproportionate in smokers with CD. The review also highlights potential mechanisms involved and factors that might affect patients' smoking habits. The clinical and scientific implications of the data are discussed.

Colonic treatments and targets: issues and opportunities

The colon provides a plethora of therapeutic opportunities. There are multiple disease targets, drug molecules, and colon-specific delivery systems to be explored. Clinical studies highlight the potential for systemic delivery via the colon, and the emerging data on the levels of cell membrane transporters and metabolic enzymes along the gut could prove advantageous for this. Often efflux transporters and metabolic enzyme levels are lower in the colon, suggesting a potential for improved bioavailability of drug substrates at this site. The locoregional distribution of multiple metabolic enzymes (including cytochromes), efflux transporters (including P-glycoprotein and breast cancer resistance proteins), and influx transporters (including the solute carrier family) along the intestine is summarized. Local delivery to the colonic mucosa remains a valuable therapeutic option. New therapies that target inflammatory mediators could improve the treatment of inflammatory bowel disease, and old and new anticancer molecules could, when delivered topically, prove to be beneficial adjuncts to the current systemic or surgical treatments. New issues such as pharmacogenomics, chronotherapeutics, and the delivery of prebiotics and probiotics are also discussed in this review. Targeting drugs to the colon utilizes various strategies, each with their advantages and flaws. The most promising systems are considered in the light of the physiological data which influence their in vivo behavior.