Publications by authors named "Caroline Chevarin"

Background: A subset of patients with ileal Crohn's disease (CD) are colonized with adherent-invasive Escherichia coli (AIEC).

Objective: This prospective trial tested the efficacy of antibiotics for endoscopic response in CD patients colonized with AIEC.

Design: Patients with endoscopically active, ileal CD, colonized with AIEC, were randomized to receive oral ciprofloxacin and rifaximin or double placebo for 12 weeks.

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Article Synopsis
  • The PACIFIC study examined the presence of Adherent-Invasive E. coli (AIEC) in Crohn's disease patients from France and Hong Kong, finding similar prevalence rates (24.5% in France vs. 30.0% in Hong Kong).
  • Antibiotic resistance was notably higher in AIEC strains from Hong Kong, particularly against multiple antibiotics, compared to those from France.
  • All AIEC strains from both regions showed sensitivity to an EcoActive™ phage cocktail, indicating potential for this treatment to be effective globally against AIEC in Crohn's disease.
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We investigated the role of ChiA and its associated polymorphisms in the interaction between Crohn's disease (CD)-associated adherent-invasive (AIEC) and intestinal mucosa. We observed a higher abundance of among the metagenome of CD patients compared to healthy subjects. In dextran sulfate sodium-induced colitis mice model, AIEC-LF82∆ colonization was reduced in ileal, colonic and fecal samples compared to wild-type LF82.

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Purpose: High-intensity interval training (HIIT) can efficiently decrease total and (intra-)abdominal fat mass (FM); however, the effects of running versus cycling HIIT programs on FM reduction have not been compared yet. In addition, the link between HIIT-induced FM reduction and gut microbiota must be better investigated. The aim of this study was to compare the effects of two 12-wk HIIT isoenergetic programs (cycling vs running) on body composition and fecal microbiota composition in nondieting men with overweight or obesity.

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  • The study aims to investigate the relationship between treatment response to neoadjuvant chemoradiotherapy (CRT) and intestinal microbiota, particularly focusing on Colibactin-producing E. coli (CoPEC), in patients with mid and low rectal cancer.
  • A prospective clinical study involving 200 patients will collect and analyze stool samples at different stages of treatment to evaluate microbiota composition and detect CoPEC, while also assessing tumour response and survival outcomes.
  • The research has ethical approval and aims to identify factors that could help tailor treatment strategies for rectal cancer patients.
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Adherent-invasive Escherichia coli (AIEC) were investigated for their involvement in the induction/chronicity of intestinal inflammation in Crohn's disease (CD). AIEC gut establishment is favoured by overexpression of the glycoprotein CEACAM6 in the ileal epithelium. We generated a transgenic mouse model, named 'Vill-hCC6', in which the human CEACAM6 gene was under the control of the villin promoter, conditioning expression in the small intestine.

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Adherent invasive (AIEC) has been implicated in the pathogenesis of Crohn's disease (CD) in Western populations. Whether the presence of AIEC is also seen in CD populations of different genetic susceptibility and has negative impact on host microbiota ecology and therapeutics are unclear. AIEC presence was assessed in ileal tissues of 60 Hong Kong Chinese patients with CD and 56 healthy subjects.

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Background And Aims: The identification of Crohn's disease (CD)-associated adherent and invasive Escherichia coli (AIEC) is time-consuming and requires ileal biopsies. We aimed to identify a faster and less invasive methods to detect ileal colonization by AIEC in CD patients.

Methods: CD patients requiring ileo-colonoscopy were consecutively enrolled in this prospective multicenter study.

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Natural mineral water (NMWs) intake has been traditionally used in the treatment of various gastrointestinal diseases. We investigated the effect of two French NMWs, one a calcium and magnesium sulphate, sodium chloride, carbonic, and ferruginous water (NMW1), the other a mainly bicarbonate water (NMW2) on the prevention of intestinal inflammation. Intestinal epithelial cells stimulated with heat inactivated or HO were treated with NMWs to evaluate the anti-inflammatory effects.

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Background: Adherent-invasive (AIEC) have been implicated in the etiology of Crohn's disease. The AIEC reference strain LF82 possesses a pathogenicity island similar to the high pathogenicity island of spp., which encodes the yersiniabactin siderophore required for iron uptake and growth of the bacteria in iron-restricted environment.

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Background: Altered function of serotonin receptor 1A (5-HT1AR) has been consistently implicated in anxiety, major depressive disorder and resistance to antidepressants. Mechanisms by which the function of 5-HT1AR (expressed as an autoreceptor in serotonergic raphe neurons and as a heteroreceptor in serotonin [5-HT] projection areas) is altered include regulation of its expression, but 5-HT1AR trafficking may also be involved.

Methods: We investigated the consequences of the lack of Yif1B (the 5-HT1AR trafficking protein) on 5-HT neurotransmission in mice, and whether Yif1B expression might be affected under conditions known to alter 5-HT neurotransmission, such as anxious or depressive states or following treatment with fluoxetine (a selective serotonin reuptake inhibitor) in humans, monkeys and mice.

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Introduction: Colorectal cancer (CRC) is still associated with poor prognosis, especially in patients with advanced disease. Development of new prognostic tools replacing or supplementing those routinely used is definitely needed, with the aim to optimise and personalise treatment strategies. Gut microbiota composition and body composition profile (obesity, sarcopenia and metabolic syndrome) have recently been reported separately as new relevant prognostic factors for postoperative surgical and oncologic outcomes following CRC surgery.

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Crohn's disease is characterized by abnormal ileal colonization by adherent-invasive (AIEC) and expansion of mesenteric adipose tissue. This study assessed the preventive effect of spontaneous physical activity (PA) on the gut-adipose tissue in a mouse model that mimics Crohn's disease susceptibility. Thirty-five CEABAC10 male mice performed spontaneous PA (wheel group; n = 24) or not (controls; n = 11) for 12 weeks.

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Intestinal microbiome dysbiosis has been consistently described in patients with IBD. In the last decades, , and the adherent-invasive (AIEC) pathotype in particular, has been implicated in the pathogenesis of IBD. Since the discovery of AIEC, two decades ago, progress has been made in unravelling these bacteria characteristics and its interaction with the gut immune system.

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Background: Desensitization and blockade of 5-HT2C receptors (5-HT2CR) have long been thought to be central in the therapeutic action of antidepressant drugs. However, besides behavioral pharmacology studies, there is little in vivo data documenting antidepressant-induced 5-HT2CR desensitization in specific brain areas.

Methods: Mice lacking the 5-HT reuptake carrier (5-HTT(-/-)) were used to model the consequences of chronic 5-HT reuptake inhibition with antidepressant drugs.

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Background: Using the R6/1 transgenic mouse model of Huntington's disease (HD), we have recently shown that acute administration with the dopamine-norepinephrine reuptake inhibitor bupropion was able to rescue depressive-like behaviours in female HD mice at 12weeks of age.

Objective: In this present study, we aimed to further investigate the dopamine system as well as specifically measure dopamine transporter (DAT) and D1 receptor function in female versus male R6/1 HD mice at a very early stage of the disease.

Methods: We assessed the effects of acute administration of bupropion and the dopamine D1 receptor agonist SKF-8129 on spontaneous locomotor activity in 8-week-old HD and wild-type (WT) mice.

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Serotonin (5-HT)2C receptors play a role in psychoaffective disorders and often contribute to the antidepressant and anxiolytic effects of psychotropic drugs. During stress, activation of these receptors exerts a negative feedback on 5-HT release, probably by increasing the activity of GABAergic interneurons. However, to date, the GABA receptor types that mediate the 5-HT2C receptor-induced feedback inhibition are still unknown.

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Article Synopsis
  • Spinal cord lesions in humans lead to motor deficits, neurovegetative issues, and severe neuropathic pain that doesn't respond well to traditional painkillers.
  • Research focused on sensory changes, drug responses, and gene expression related to injury in rats after complete spinal cord transection (SCT) at the T8-T9 level, examining effects over two months.
  • Results showed significant mechanical and cold sensitivity, with gene markers for nerve injury and inflammation being strongly expressed, while certain drugs (like ketamine and morphine) were effective in reducing pain responses, contrasting with others that showed no effect.
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Exercise improves the central nervous system (CNS) functions and is widely recommended for neurological patients with, e.g., Alzheimer's and Parkinson's disease (PD).

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Bee venom has recently been suggested to possess beneficial effects in the treatment of Parkinson disease (PD). For instance, it has been observed that bilateral acupoint stimulation of lower hind limbs with bee venom was protective in the acute 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. In particular, a specific component of bee venom, apamin, has previously been shown to have protective effects on dopaminergic neurons in vitro.

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The loss of nigral dopaminergic neurons in Parkinson's disease (PD) is believed to result from interactions between genetic susceptibility and environmental factors. Although loss-of-function mutations in the parkin gene cause early-onset familial PD, the hybrid 129Sv-C57BL/6 parkin-deficient mice did not display spontaneous degeneration of the nigrostriatal pathway or enhanced vulnerability to neurotoxicity induced by 6-hydroxydopamine (6-OHDA) or intraperitoneal 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxication. We aimed to re-evaluate the role of parkin in a pure C57BL/6 background after an acute intranasal (i.

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Myotonic dystrophy type 1 is a complex multisystemic inherited disorder, which displays multiple debilitating neurological manifestations. Despite recent progress in the understanding of the molecular pathogenesis of myotonic dystrophy type 1 in skeletal muscle and heart, the pathways affected in the central nervous system are largely unknown. To address this question, we studied the only transgenic mouse line expressing CTG trinucleotide repeats in the central nervous system.

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Psychiatric disorders such as depression and anxiety are reported in patients with Huntington's disease (HD). Recent studies suggest beneficial effects of environmental enrichment (EE) on HD progression possibly through the serotonergic system. We investigated the potential effectiveness of EE in correcting the affective-like phenotype of female R6/1 HD mice.

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Decreasing the bioavailability of serotonin (5-HT) by inhibiting its biosynthesis may represent a useful adjunctive treatment of pulmonary hypertension (PH). We assessed this hypothesis using LP533401, which inhibits the rate-limiting enzyme tryptophan hydroxylase 1 (Tph1) expressed in the gut and lung, without inhibiting Tph2 expressed in neurons. Mice treated repeatedly with LP533401 (30-250 mg/kg per day) exhibited marked 5-HT content reductions in the gut, lungs, and blood, but not in the brain.

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Using the R6/1 mouse model of Huntington disease (HD), we have recently shown that voluntary physical activity was able to correct the depressive-like behaviours exhibited by the HD animals at a pre-motor symptomatic stage of the disease. Using the high performance liquid chromatography system, we have now evaluated the effect of exercise on monoamine metabolism in HD mice. We found that serotonin and its metabolite as well as dopamine and noradrenaline were reduced across several brain regions in female R6/1 animals.

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