Irritable bowel syndrome (IBS), majorly characterized by irregular bowel movements and abdominal pain, is one of the most prevalent functional gastrointestinal disorders (FGIDs) in the world. Disturbance of gut microbiota, closely linking with gut dysfunction, has been regarded as one of important pathogenetic factors for IBS. However, gut microbiota-driven mechanism underlying IBS remains unclear, which leads to inefficient and non-specific effects of current microbiota-oriented therapy. In this thesis, function-based microbiota investigation with combination of metagenomic and metabolomic analyses was separately performed in IBS cohort and model to precisely link pathogenic species with disordered GI motor function. A series of microbiota manipulation studies in rodents were conducted to explore bacteria-driven molecular mechanism. Firstly, a pilot study with 'omics' analyses revealed fecal microbial structure significantly varied in IBS patients with disorder GI motility relative to healthy controls (HC). Such changed IBS enterotype was functionally characterized by disturbed metabolism of bile acids (BAs) that are previously proved to regulate GI motor function. It indicates microbiota-driven GI dysmotility relevant to disturbance of BA metabolism in IBS. Secondly, a systematic review with meta-analysis was performed to comprehensively understand existing findings related to BA metabolism and its linkage with IBS. Results showed that abnormal BA excretion, previously reported in at least one IBS subtype, is associated with dysregulation of BA synthesis, marked with abnormalities of circulating indices 7α-hydroxy-4-cholesten-3-one (C4) and fibroblast growth factor 19 (FGF19). However, what's the role of gut microbiota in abnormal BA excretion is undetermined. Thirdly, to explore possible role of gut microbiota in abnormal BA excretion in IBS, BA metabolites and BA-related microbiome were simultaneously analyzed in stools of recruited subjects. Results found that total BA and microbiota-derived BAs were remarkably elevated in a quarter of IBS-D patients (BA+IBS-D) who exhibited more frequent defecation, higher level of serum C4 but lower level of serum FGF19 than those with normal BA excretion (BA-IBS-D). In line with metabolic results, abundances of BA-metabolizing bacteria, particularly Clostridium scindens (C. scindens) simultaneously expressed hdhA and bais that are responsible for BA 7α oxidation and dehydroxylation, were highly enriched in fecal metagenomes of such particular IBS-D population. These findings suggest the increased BA-metabolizing microbiome is associated with the dysregulated host BA synthesis in the subgroup of BA+IBS-D patients. Fourthly, by analyzing metabolites and bacteria related to BA metabolism, a neonatal maternal separation (NMS)-induced IBS-D rat model characterized by accelerated GI motility and excessive BA excretion were found to largely mimic gut microbial BA metabolism in BA+IBS-D patients. Specifically, intraluminal total and secondary BAs were significantly elevated in the large intestinal lumens (cecum, proximal colon and feces) of NMS rats, together with increased abundances of hdhA- and bais-expressing Clostridium species, including C. scindens. Moreover, quantitative polymerase chain reaction (PCR) analysis showed upregulated mRNA expression of cholesterol 7 α-hydroxylase (CYP7A1) whereas downregulated mRNA expression of small heterodimer partner (SHP) in the liver of NMS rats, indicating enhanced hepatic BA synthetic level. These observations based on such IBS-D model suggest the association of excessive BA-metabolizing microbiome and increased hepatic BA synthesis. Fifthly, to further clarify whether excessive BA-metabolizing bacteria contribute to enhanced hepatic BA synthesis and to explore the underlying molecular mechanism, we performed bacterial intervention in pseudo germ-free (GF) or/and specific pathogen free (SPF) mice by transplantation of human fecal microbiota and the signal strain C. scindens. Compared with GF mouse recipients of HC and BA-IBS-D fecal microbiota, BA+IBS-D fecal microbial recipients displayed shorter GI transit and increased subsistence of C. scindens in the cecal contents. In line with higher level of serum C4, taurine-conjugated BA contents and mRNA expressions of BA synthetase CYP7A1 and sterol 12α-hydroxylase (CYP8B1) were significantly elevated in the liver of BA+IBS-D recipients. These findings showed bioactive effects of BA+IBS-D fecal microbiota with enrichment of C. scindens on hepatic BA synthesis. Next, to further confirm the effects of the species C. scindens on host BA synthesis, we individually colonized C. scindens strains (ATCC 37504) to pseudo GF and SPF mice. Results showed both mice models with single strain colonization exhibited accelerated GI transit and higher contents of hepatic total and taurine-conjugated BAs compared with individual vehicles treated with PBS. Combining metabolic changes, the upregulated expressions of hepatic CYP7A1 mRNA in colonized mice indicate that C. scindens substantially promote hepatic BA synthesis in colonized mice. Furthermore, contents of taurine-conjugated BAs, served as natural antagonists of farnesoid X receptor (FXR) that negatively control of new BA synthesis, were elevated in ileal lumens of colonized mice. Expressions of FXR-targeted genes SHP and fibroblast growth factor 15 (FGF15) were consistently reduced in the liver and ileum tissues of colonized mice, respectively. Results suggest that suppression of FXR-mediated feedback signaling is involved in Clostridium-driven hepatic BA oversynthesis, which deserve the further investigation. Collectively, the works of this thesis integrating clinical and animal studies indicate that BA-metabolizing bacteria, particularly C. scindens, enhance hepatic BA synthesis and consequently leads to BA overexcretion. It provides novel bacteria-driven mechanism for enhanced GI motility, and supply a direction in precise microbiota-related pathogenesis and medication for IBS-D population in future.

Irritable bowel syndrome (IBS) is characterized by chronic abdominal pain/discomfort along with altered bowel habits, which accounts for a large proportion of gastrointestinal (GI) disorders worldwide. While psychiatric distress like depression is one of the most frequent comorbidities in IBS patients, which not only influences the quality of life, it also leads to a substantial economic burden and inefficient treatment in IBS patients. Inflammation, altered activities of the HPA axis, aberrant central neuroplasticity and neurotransmission have been highly regarded as pathogenic factors of the depression. Whereas, in recent years, dysfunctions in the gut microbial community has been increasingly discovered to provoke depression disorder. Considering that gut dysbiosis plays causal role in IBS progression, dysfunction of the gut microbiota has been speculated for contributing to the depressive symptoms in IBS (IBS-DP) patients. However, whether and how gut dysbiosis affecting IBS-DP patients remain unclear. We hypothesized that gut microbiota changes contribute to the development of IBS-DP and the change of gut microbiota-driven metabolites induces the structural and/or functional changes of the central nervous system (CNS), thus resulting in the development of IBS-DP. In this thesis, IBS patients with and without depression and animal models of IBS have been systematically studied, to investigate whether gut dysbiosis mediates depressive disorder in IBS. Firstly, we conducted a cross-sectional study involving the distribution of depressive disorder in the IBS population of Hong Kong. According to this survey, we found that there is 36.6% (135/369) of IBS patients showed symptoms of depression. The severity of depressive symptoms was positively associated with the harshness of visceral pain and bloating signatures in IBS patients. Secondly, in comparison to the non-depression of IBS (IBS-ND) group, faecal metagenomic results unveiled the disrupted gut microbiota in IBS-DP patients, mainly with the deficiency of several beneficial bacterial groups, including Akkermansia, Bifidobacterium and Eubacterium, whereas the gut microbiota profile between IBS-ND patients and healthy controls (HCs) showed no significant changes. Compared with HCs, enzyme-linked immunosorbent Assay (ELISA) results showed higher levels of serum IL-1β, IL-6, and TNF-a in IBS-DP patients, indicating a low-grade peripheral inflammation in IBS-DP patients. Moreover, the abundance of Akkermansia muciniphila (A. muciniphila), was negatively correlated with Hamilton Rating Scale for Depression (HAMD) score and Zung Self-Rating Depression Scale (SDS) score, IL-1β, TGF-β, and TNF-a in IBS-DP patients. These findings indicate that gut dysbiosis, especially deficiency in A. muciniphila, is related to the depressive symptoms and inflammation in IBS-DP patients. Thirdly, in a neonatal maternal separation (NMS) rat model, behavioural tests such as colorectal distention (CRD) test, open field test (OFT), forced swimming test (FST), and sucrose preference test (SPT) results showed visceral hypersensitivity and depression symptoms in rats. These results indicate that the model can successfully mimic the visceral hyperalgeisa and the depression-like behaviour of IBS-DP. Immunohistochemical analysis showed an altered morphology and decreased the quantity of astrocytes in the hippocampus of NMS rats when compared with that of controls. More importantly, the mRNA expressions of genes related to Astroglial glutamate transmission including glutamate transporters (GLTs), glutamate receptors, and also glutamate-related exchangers, as well as astrocyte biomarker glial fibrillary acidic protein (GFAP), which are mediated with chronic inflammation and/or stress, were decreased in NMS rats when compared with the control group. These results indicate that impaired astroglial glutamate neurotransmission in NMS rats. Furthermore, pseudo-GF rats with faecal microbiota transplantation (FMT) of NMS microbiota were also conducted, and results showed that the association of A. muciniphila deficiency, depressive-like behaviours and impaired astroglial glutamate neurotransmission were repeated in the rat recipients. These results indicate a causal relationship between NMS microbiota and depressive phenotype, involving dysfunction of the astrocyte- glutamate pathway. Fourthly, to further verify the role of A. muciniphila in NMS microbiota-induced depressive phenotype and impaired astrocytic glutamate pathway, we orally administered live and heat-killed A. muciniphila bacteria in NMS adult rats. A. muciniphila (108 CFU in 1mL PBS) was administered once-daily for four consecutive weeks. Besides, rifaximin and fluoxetine were also separately treated in NMS rats as control groups. Rifaximin is a broad-spectrum GI-specific antibiotic that is commonly used for IBS treatment, and fluoxetine, a selective serotonin re-uptake inhibitor, is one of the most frequently prescribed anti-depressants. The results showed that A. muciniphila efficiently improved depressive-like behaviours, attenuated the impaired astrocytic glutamate neurotransmission, as well as restored the normal morphology and number of astrocytes in the hippocampus of NMS rats. While rifaximin-treated rats only exhibited amelioration of visceral pain, and fluoxetine group mainly performed antidepressant effect, without any significant change in astrocytic glutamate neurotransmission impairment. These results demonstrate that A. muciniphila improves depressive symptoms in IBS phenotype and ameliorate astroglial-glutamatergic pathway dysfunction. Whether and how A. muciniphila modulates astroglial glutamate transmission, therefore leading to the improvement of depressive symptom in IBS, remains to be further investigated. Taken together, the works of this thesis, combining both clinical and animal studies reveal that gut dysbiosis, particularly deficiency of A. muciniphila, contributes to the development of IBS-DP via regulating the astroglial glutamatergic pathway. This study gives a different direction to microbial-guided therapy for the IBS-DP patients in the future

M.A. / The purpose of this study is to investigate the effects of an individualized holistic psychotherapy and synergistic stress management programme for the treatment of Irritable Bowel Syndrome (IBS) and stress, both of which are common disorders in this present day and age. IBS is a functional bowel disorder of the gastrointestinal tract that leads to change in bowel habits with the additional features of abdominal pain and distension (Drossman, 1994b). This functional disorder has been associated with stress since time immemorial and it is only recently that research has begun to examine how and by what mechanisms IBS and stress are related. A review of the literature suggests a resurgent interest in IBS and stress. Tantalizing questions like ‘IBS – irritable bowel, irritable body, irritable brain or irritable mind?’ gives one an idea of the genesis from which the disorder has come, the complications in which it has been mired and the directions in which it is aspiring to go (Farthing, 1995). Using both the historical context and the present level of understanding in the research literature, one becomes aware of the shifting paradigm from the dualistic Cartesian-Newtonian biomedical perspective, to the biopsychosocial and integrative mind-body approaches which reflect the move to a holistic and non-linear quantum scientific worldview. The ecosystemic paradigm on which the present study is based, represents this shift whereby systemic changes in cyclical rhythmic patterns within the psychophysiology of clients reflect new ways of conceptualizing psychosomatic (mind-body) ill-health (Weiner, 1992). Within the behavioural and medical health fields, both psychologists and physicians as well as a number of other disciplines are moving towards more integrative solutions which include the mind-body-spirit dimensions of the individual. Drossman, Whitehead and Camilleri (1997) have begun to consider the individualized expression of the illness in the patient and to situate him among his wider systems, as well as incorporating a referral team approach to the treatment of IBS. Salt (1997) extends the use of the biopsychosocial model to include the spiritual dimension in his treatment of IBS patients. Broom (1997) weaves the various internal systems of the person into the story of the client’s illness that integrates the mind and body. The psychologically based holistic intervention of this study was developed in response to the calls for more integrative approaches to treatment which incorporate whole-person care. The specific aim of this study is to compare a group of IBS participants who receive the holistic individualized psychotherapy and synergistic stress management intervention with a group of IBS participants who do not receive the treatment. The sample consisted of two groups, an experimental (N = 20) group and a control (N = 20) group. The IBS Client Questionnaire also known as the Functional Bowel Disorder Severity Index (FBDSI) (Drossman, Zhiming, Toner, Diamant, Creed, Thompson, Read, Babbs, Barreiro, Bank, Whitehead, Schuster & Guthrie 1995) was used to verify a diagnosis of IBS as well as a measure of the severity of symptoms. This index is based on the current international diagnostic criteria for IBS. The Occupational Stress Inventory was used as a measure of vocational stress and was developed to provide an integrated theoretical model linking sources of stress in the work environment, psychological strains experienced by individuals as a result of work stressors and the coping resources available to counterbalance the effect of stressors and alleviate strain. It consists of three scales, namely Occupational Roles, Personal Strain and Personal Resources scales respectively. Wilks’ Lambda was used for the between-groups comparisons between the intervention and non-intervention groups and Paired Samples t-test was used for the within-groups analysis. The comparisons were made in terms of improvement in symptoms, determined by the Functional Bowel Disorder Severity Index (FBDSI) and lowering of occupational stress, determined by two of the scales of the Occupational Stress Inventory, namely the Occupational Roles and Personal Strain scales and an increase in coping responses determined by the Personal Resources scale. Both of these were administered as pre- and post-test measures before and three months after the intervention was completed. The results of the study indicate that the experimental group of IBS participants who received the intervention improved in symptom severity, their occupational stress was lowered and they began utilizing more coping resources than the group of IBS participants who did not receive the intervention. Thus it is concluded that an individualized holistic approach for the treatment of IBS is indicated and that individuals with refractory IBS can be helped to manage their illness and their lives. In particular, this psychologically based study confirms a very definite and specific place for psychologists in the treatment of clients with IBS and stress. An invitation was extended to the control group to use the facilities for therapeutic intervention offered by the RAU Psychogastroenterology project once the post-tests had been completed, thus addressing any ethical questions that could have arisen. This was an initial investigation using an ecologically based meta-theoretical framework as well as specific stress techniques for the holistic treatment of clients. A number of recommendations arose from this particular intervention and are included for future studies.

Background. Although irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder with an absence of demonstrable pathology, it is associated with significant impairment of quality of life and causes a heavy burden on the health care system. As conventional IBS treatments are far from satisfactory, people turn to Complementary and Alternative Medicine (CAM). One of the most acceptable CAM treatments is acupuncture, which has been considered to be effective in alleviating abdominal bloating, increasing rectal pain threshold, and improving the general well being of IBS patients. However, the underlying mechanisms of these therapeutic effects remain unknown. This study is an investigation of the therapeutic mechanisms of acupuncture treatment of IBS. / Conclusion. Acupuncture attenuates visceral hyperalgesia by inhibiting 5-HT and c-Fos activity in the brain-gut axis. This observation may shed light on possible mechanisms by which acupuncture alleviates symptoms of IBS. / Study 1. A Neonatal Maternal Separation Stress Model (NMSS) was tested. Our results showed that this model was a reliable and stable model for IBS animal study and that visceral hyperalgesia was associated with increased serotonin (5-HT) and c-Fos activity of the brain-gut axis. / Study 2. Two methods were used to test visceral hyperalgesia in response to colorectal distension (CRD), namely Abdominal Withdrawal Response (AWR) and Electromyogram (EMG). There methods were compared for their effectiveness in measuring visceromotor response (VMR) in a NMSS rat model. Our results showed that EMG is the more reliable tool for evaluating VMR to CRD in NMSS rats. / Study 3. There were three parts to this study. First, we reviewed the TCM literature on the use of acupuncture in IBS and concluded that the two most commonly used acupoints for this condition are ST-36 and CV-12 and that, of the two, ST-36 may be the more appropriate acupoint for treatment. Second, we tested invasive and non-invasive sham acupuncture (placebo) and found that neither produces any therapeutic effect when compared to real electroacupuncture. Third, we used the NMSS rat as the animal model, ST-36 as the treatment acupoint, non-invasive sham acupuncture as the placebo, and EMG as the tool to evaluate VMR in response to CRD alter acupuncture intervention. Our results showed that acupuncture not only attenuated 5-HT and c-Fos activity but also reduced visceral hyperalgesia in the NMSS rat. / Ziea, Tat Chi. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3423. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 122-141). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Background: Irritable bowel syndrome (IBS) is a common gastrointestinal (GI) disorder. GI symptoms and impaired quality of life affect between 10-20% of all adults, corresponding to about 25-50% of all patients who visit a gastroenterologist’s clinic. In recent years, several novel mechanisms of IBS that likely relate to previously established theories have been identified. Inflammation, postinfectious low-grade inflammation, immunological and genetic predisposition along with altered microbiota are critical in IBS development, while several dietary factors may also play a role in this syndrome. However, none of these factors accounts for the full repertoire of IBS symptoms, and the pathophysiology of this condition is not fully understood. The overarching aim of this study was to investigate the nutrient intakes, GI microbiota and the effect of Lactobacillus plantarum (L.plantarum) 299v in IBS patients. Sub-aims: 1) Update healthcare professionals on current probiotic information and provide an overview of probiotic treatment approaches, with special emphasis on IBS, 2) conduct a well designed randomised, double blind, placebo-controlled trial (RCT) with L. plantarum 299v as part of an intervention and establish whether a course of probiotics may alleviate undesirable symptoms of IBS and improve quality of life, 3) assess nutrient intake in patients with irritable bowel syndrome (IBS) compared to dietary recommendations, 4) validate and assess the reproducibility of food records and 5) identify possible nutrient risk components for establishing GI microbiota involved in IBS and as part of an intervention, determine whether a course of probiotics may alter stool microbiota. Results: 1) A review article published by the author provides an overview of current probiotic treatment options to health care professionals and indicates certain probiotics are a promising therapeutic treatment option for management of IBS symtpoms, 2) the effects of the single strain probiotic, L. plantarum 299v, supplementation was evaluated in a RCT. Compared to placebo, the probiotic supplementation showed no significant reduction in GI symptom severity scores, particularly abdominal pain relief. Quality of life was also not improved in the treatment versus control group. Both the treatment and placebo groups improved significantly over the trial period, indicating a large placebo effect, 3) nutrient intakes of the IBS patients compared to current dietary reference recommendations indicates that this group of patients are at risk for nutrient inadequacies in key macro and micronutrients, 4) the validity and reliability of the dietary data showed good reliability but poor validity as measured by plasma fatty acids and 5) the GI microbiota composition in the phenotypically different diarrhoea-predominant IBS (D-IBS) vs. constipation-predominant IBS (C-IBS) showed that D-IBS patients had significantly lower counts of Lactobacillus plantarum compared to C-IBS patients. The probiotic had no significant effects on the GI microbiota as measured by quantitative polymerase chain reaction (qPCR). It was found that nutrient intakes had a significant impact on the microbiota. Lower fibre intakes were associated with higher Bacteroides spp., lower Bifidobacteria bifidum and Lactobacillus plantarum counts in both IBS groups. Conclusion: Taken together, L.plantarum 299v did not alleviate the GI symptoms of IBS, nor was it associated with significant changes in the GI microbiota. IBS patients may be at risk of key nutrient inadequacies. The influence of nutrient intakes on the GI microbiota provides an attractive explanation as a potential pathophysiological factor for IBS. / AFRIKAANSE OPSOMMING: Agtergrond: Prikkelbare derm-sindroom (PDS) is ‘n algemene gastro-intestinale (GI) stoornis. GI simptome affekteer die lewenskwaliteit van 10-20% van alle volwassenes. Dit stem ooreen met ongeveer 25-50% van alle pasiënte wat ‘n gastroënteroloog konsulteer. Verskeie oorspronklike meganismes vir die ontwikkeling van PDS is onlangs identifiseer. Inflammasie, post-infektiewe lae-graadse inflammasie, immunologiese en genetiese vatbaarheid tesame met veranderde mikrobiota is krities vir die ontwikkeling van PDS. Sekere dieetfaktore mag ook bydraend wees tot hierdie sindroom. Geen van hierdie faktore is egter verantwoordelik vir die volle spektrum van PDS simptome nie en die patofisiologie van die toestand word ook nog nie ten volle verstaan nie. Die oorkoepelende doel van hierdie studie is om nutriëntinname, GI mikrobiota en die uitwerking van L.plantarum 299v in PDS pasiënte bepaal. Sub-doelwitte: 1) Om gesondheidswerkers in te lig aangaande die nuutste inligting oor probiotika en om ‘n oorsig van probiotika behandelingsopsies te verskaf, met spesiale klem op PDS, 2) om ‘n goed beplande ewekansige, dubbel-blinde, plasebo-beheerde kliniese studie met L.plantarum 299v as deel van die intervensie uit te voer om sodoende te bepaal of ‘n kursus probiotika ongewensde simptome van PDS kan verbeter en lewenskwaliteit sodoende verhoog, 3) om nutriëntinname in pasiënte met PDS te bepaal vergeleke met dieet aanbevelings, 4) om die geldigheid en herhaalbaarheid van voedselrekords te bepaal en 5) om moontlike nutriënt risikokomponente vir die ontwikkeling van GI mikrobiota betrokke in PDS te identifiseer en om as deel van ‘n intervensie te bepaal of ‘n kursus probiotika stoelgang mikrobiota patrone verander. Resultate: 1) ‘n Oorsigartikel gepubliseer deur die kandidaat dui probiotika aan as ‘n belowende terapeutiese opsie in die behandeling van PDS simptome, 2) die effek van ‘n enkelstam probiotikum, L.plantarum 299v, is evalueer deur ‘n ewekansige, dubbel-blinde, plasebo-beheerde kliniese studie. Vergeleke met die plasebo, het probiotiese aanvulling geen betekenisvolle vermindering in die GI simptome in PDS pasiënte tot gevolg gehad nie. Lewenskwaliteit het ook nie verbeter in die behandelde versus die kontrole groep nie. Beide die behandelde en plasebo groepe het aansienlik verbeter oor die studietydperk, wat ‘n groot plasebo effek aandui, 3) nutriëntinname van die PDS groep vergeleke met huidige dieetaanbevelings, dui daarop dat hierdie groep pasiënte ‘n risiko het vir die ontwikkeling van kern nutriënttekorte (makro- en mikronutriënte), 4) die geldigheid en betroubaarheid van die dieetdata dui op goeie betroubaarheid, maar swak geldigheid soos bepaal deur plasma vetsure en 5) die dermkanaal mikrobiotiese samestelling in die verskillende fenotipes, diarree-oorheersende PDS (D-PDS) vs. konstipasie-oorheersende PDS (K-PDS) dui daarop dat D-PDS pasiënte aansienlike minder Lactobacillus plantarum gehad het vergeleke met K-PDS pasiënte. Die probiotikum het geen beduidende uitwerking op die oorheersende mikrobiota gehad nie, soos gemeet deur kwantitatiewe polimerase kettingreaksie (kPKR). Daar is gevind dat dieet ‘n beduidende impak op die mikrobiota gehad het. Daar is ‘n verband tussen laer vesel inname en hoёr Bacteroides spp. en laer Bifidobacteria bididum en Lactobacillus plantarum tellings gevind in beide PDS groepe. Gevolgtrekking: Die L.plantarum 299v enkelstam probiotikum het nie die gastrointestinale simptome van PDS pasiënte verlig nie en daar is ook geen beduidende veranderinge in die mikrobiota gevind nie. PDS pasiënte mag ‘n verhoogde risiko toon vir kern nutriënttekorte. Die invloed van nutriëntinname op GI mikrobiota verskaf ‘n belowende verduideliking as ‘n potensiële patofisiologiese faktor in PDS.

Doctor of Philosophy / Nineteenth century philosophy and anatomy regarded the nervous system as the only pathway of communication between the brain and body but now, research in the field of psychoneuroimmunology (PNI) has provided evidence to prove the age-old belief that there is a connection between the mind (or mental/emotional states) and the body. Researchers in PNI have now shown that the communication between the nervous and immune systems is bi-directional – i.e. there is a psychological reaction to physical disease and a somatic presentation of psychological disorders - and that the immune system, the autonomic nervous system, the endocrine system and the neuropeptide systems all communicate with each other by means of chemicals called messenger molecules or ligands. This paper outlines research into the treatment of Irritable Bowel Syndrome (IBS) with hypnotherapy, taking into account the mind-body connection and treating both the patient’s physiological and emotional/psychological symptoms rather than treating the physiological symptoms only. In other words, using a more holistic approach to the treatment of IBS. IBS is probably the most common functional gastrointestinal disorder encountered by both gastroenterologists and physicians in primary care. It is estimated that from 10% to 25% of the general population suffer from this condition and that it comprises about 30-50% of the gastroenterologists’ workload, yet the aetiology of IBS is unknown and, so far, there is no cure. Researchers are beginning to view IBS as a multi-faceted disorder in which there appears to be a disturbance in the interaction between the intestines, brain, and autonomic nervous system, resulting in an alteration in the regulation of bowel motility and/or sensory function. Most researchers agree that a subset of IBS sufferers have a visceral hypersensitivity of the gut or, more specifically, an increased perception of sensations in the gut. To date, studies of IBS have proposed previous gastroenteritis, small intestine bacterial overgrowth, psychosocial factors, a genetic contribution, and an imbalance of neurotransmitters as either possible causes or playing a part in the development of IBS. It is generally agreed that a patient’s emotional response to stress can exacerbate the condition. In section 1 of the thesis, the introduction, a detailed description and background appropriate to the study undertaken are provided, including aspects of epidemiology, diagnostic symptom criteria and clinical relevance of the Irritable Bowel Syndrome. Previous studies of various forms of treatment for IBS are discussed with the main emphasis being on treatment with hypnotherapy. All these therapies have concentrated on either mind or body treatments whereas this study demonstrates how hypnotherapy, and the use of imagery, addresses both mind and body. Finally, the rationale for the current study and the specific aims of the thesis are outlined. In section 2, the methodology and assessment instruments used in the clinical trial are discussed, as well as recruitment processes, research plan and timetable, and treatment schedule. Statistical analyses are provided and the main outcomes measures of the clinical trial, its limitations and scientific implications are addressed.

Doctor of Philosophy / Nineteenth century philosophy and anatomy regarded the nervous system as the only pathway of communication between the brain and body but now, research in the field of psychoneuroimmunology (PNI) has provided evidence to prove the age-old belief that there is a connection between the mind (or mental/emotional states) and the body. Researchers in PNI have now shown that the communication between the nervous and immune systems is bi-directional – i.e. there is a psychological reaction to physical disease and a somatic presentation of psychological disorders - and that the immune system, the autonomic nervous system, the endocrine system and the neuropeptide systems all communicate with each other by means of chemicals called messenger molecules or ligands. This paper outlines research into the treatment of Irritable Bowel Syndrome (IBS) with hypnotherapy, taking into account the mind-body connection and treating both the patient’s physiological and emotional/psychological symptoms rather than treating the physiological symptoms only. In other words, using a more holistic approach to the treatment of IBS. IBS is probably the most common functional gastrointestinal disorder encountered by both gastroenterologists and physicians in primary care. It is estimated that from 10% to 25% of the general population suffer from this condition and that it comprises about 30-50% of the gastroenterologists’ workload, yet the aetiology of IBS is unknown and, so far, there is no cure. Researchers are beginning to view IBS as a multi-faceted disorder in which there appears to be a disturbance in the interaction between the intestines, brain, and autonomic nervous system, resulting in an alteration in the regulation of bowel motility and/or sensory function. Most researchers agree that a subset of IBS sufferers have a visceral hypersensitivity of the gut or, more specifically, an increased perception of sensations in the gut. To date, studies of IBS have proposed previous gastroenteritis, small intestine bacterial overgrowth, psychosocial factors, a genetic contribution, and an imbalance of neurotransmitters as either possible causes or playing a part in the development of IBS. It is generally agreed that a patient’s emotional response to stress can exacerbate the condition. In section 1 of the thesis, the introduction, a detailed description and background appropriate to the study undertaken are provided, including aspects of epidemiology, diagnostic symptom criteria and clinical relevance of the Irritable Bowel Syndrome. Previous studies of various forms of treatment for IBS are discussed with the main emphasis being on treatment with hypnotherapy. All these therapies have concentrated on either mind or body treatments whereas this study demonstrates how hypnotherapy, and the use of imagery, addresses both mind and body. Finally, the rationale for the current study and the specific aims of the thesis are outlined. In section 2, the methodology and assessment instruments used in the clinical trial are discussed, as well as recruitment processes, research plan and timetable, and treatment schedule. Statistical analyses are provided and the main outcomes measures of the clinical trial, its limitations and scientific implications are addressed.