Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022104 (irritable bowel syndrome)
 8,033 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The association between migraine and functional gastrointestinal disorders has been confirmed by many clinical observations and epidemiological studies. In most patients during the attacks of migraine, apart from various neurological and vascular symptoms, gastrointestinal disturbances occur including nausea, vomiting, abdominal pain or diarrhea. Functional gastrointestinal disorders, such as irritable bowel syndrome (IBS), are reported in migraine patients in periods between the attacks as well. On the other hand 23-53% of IBS patients have frequent headaches. Migraine and IBS often coexist with fibromyalgia and other chronic pain syndromes and functional disorders. Migraine and IBS affect approximately 10-20% of the general population, usually young adults. Both diseases are more prevalent in women, perhaps due to the role of estrogen in their pathogenesis. Looking for the common pathogenetic mechanisms of IBS and migraine the role of the brain-gut axis, neuroimmune and neuroendocrine interactions are being considered. The influence of stress on symptom occurrence and severity seems to be associated with hyperactivity of the hypothalamic-pituitary-adrenal axis. The enteric nervous system as a source of numerous neurotransmitters and visceral reflexes is a plausible common pathogenic link between IBS and migraine. In particular serotonin being the main neurotransmitter of the gastrointestinal tract plays a relevant role in the pathogenesis of IBS as well as migraine. Nowadays, agonists and antagonists of serotoninergic receptors are the most efficacious drugs for IBS and migraine therapy. Some side effects of triptans, 5-HT(1B/D) agonists, used in migraine treatment may be connected with the influence of triptans on the gastrointestinal functions. A better understanding of the relationship between migraine and IBS may result in more effective treatment of both diseases.
 ...
PMID:[Migraine and irritable bowel syndrome]. 1641 71

This study comprises assessment of autonomic function in irritable bowel syndrome (IBS) patients, focusing on meal-related changes. In 18 IBS patients (4 males, mean age 45+/-3.0 [SEM] years) and 19 healthy volunteers (6 males, mean age 41+/-3.5 years) blood pressure, heart rate, heart rate variability and muscle sympathetic nerve activity (MSNA) were assessed before, during and after consumption of a standardized meal. In pre- and postprandial phase Valsalva maneuver, cold pressor test (CPT) and deep breathing test were carried out and Visual Analog Scale (VAS) scores for nausea, bloating and pain were obtained. In the IBS group, the meal induced significantly higher VAS scores for pain (P=0.002) and bloating (P=0.02). During food intake, the increase in blood pressure, heart rate and MSNA was equal in patients and controls, but the increase of LF/HF ratio of heart rate variability was significantly higher in the IBS group (median [quartiles] 2.29 [1.14-3.00] versus 0.77 [0.25-1.81]; P=0.03). IBS patients scored lower on pre- and postprandial RRmax/RRmin ratio during deep breathing (DB ratio, P=0.03). The increase in MSNA (burst frequency) in response to CPT tended to be higher in the IBS patients (P=0.07). We conclude that reactivity to food intake, measured as muscle sympathetic nerve activity, is normal in IBS patients. The lower DB ratio and higher LF/HF ratio during food intake in IBS patients is an indication of a reduced parasympathetic reactivity. These results suggest that reduced baseline activity as well as responsiveness of the parasympathetic system could play a role in the pathogenesis of IBS.
 ...
PMID:Subtle involvement of the parasympathetic nervous system in patients with irritable bowel syndrome. 1647 93

There is convincing evidence that acupuncture (AP) is effective for the treatment of postoperative and chemotherapy-induced nausea/vomiting, as well as postoperative dental pain. Less convincing data support AP's efficacy for chronic pain conditions, including headache, fibromyalgia and low back pain. There is no evidence that AP is effective in treating addiction, insomnia, obesity, asthma or stroke deficits. AP seems to be efficacious for alleviating experimental pain by increasing pain thresholds in human subjects and it appears to activate analgesic brain mechanisms through the release of neurohumoral factors, some of which can be inhibited by the opioid antagonist naloxone. In contrast to placebo analgesia, AP-related pain relief takes some time to develop and to resolve. Furthermore, repetitive use of AP analgesia can result in tolerance that demonstrates cross-tolerance with morphine. However, it appears that not all forms of AP are equally effective for providing analgesia. In particular, electro-AP seems to best deliver stimuli that activate powerful opioid and nonopioid analgesic mechanisms. Thus, future carefully controlled clinical trials using adequate electro-AP may be able to provide the necessary evidence for relevant analgesia in chronic pain conditions, such as headache, fibromyalgia, irritable bowel syndrome and low back pain.
 ...
PMID:Mechanisms of acupuncture analgesia for clinical and experimental pain. 1673 14

5-HT3 receptors are members of the Cys-loop superfamily of ligand-gated ion channels. In both the central and the peripheral nervous systems, 5-HT3 receptors excite postsynaptic cells and modulate the release of neurotransmitters from presynaptic neurons. 5-HT3 receptors are known to be involved in mediation of nausea/emesis caused by chemo/radio-therapy and anaesthesia, and more recently have also been found to be involved in irritable bowel syndrome. 5-HT3 receptors have also been suggested to play a role in a range of other indications, including various psychiatric disorders. This review summarizes the current evidence for the contribution of 5-HT3 subunit genes to disease phenotypes arising from association studies. Furthermore, it suggests how in vitro characterization of naturally occurring genetic variants can be used to obtain a better understanding of the causal relationship between gene and disease.
 ...
PMID:Do polymorphisms in the human 5-HT3 genes contribute to pathological phenotypes? 1705 18

How to treat patients with irritable bowel syndrome (IBS) who do not respond to pharmacotherapy is an unsolved problem. Psychotherapy, which has been reported on in previous studies, is available only in specific centers. We describe in this study a novel and simple psychotherapy; that is, the fasting therapy (FT) for treatment of patients with IBS. Of 84 inpatients with IBS, 58 patients who still had moderate to severe IBS symptoms after 4-week basic treatment were investigated retrospectively. Of the 58 patients enrolled in this study, 36 underwent FT, whereas the remaining 22 received a consecutive basic treatment (control therapy). There were no significant differences in the 4-point severity scales of gastrointestinal and psychological symptoms between the 2 groups before the start of FT. The basic treatment consisted of pharmacotherapy and brief psychotherapy, whereas the FT consisted of 10 days of starvation followed by 5 days of refeeding. Changes in scores of symptoms before and after each treatment were analyzed. FT significantly improved 7 out of the 10 symptoms assessed; that is, abdominal pain-discomfort (p < .001), abdominal distension (p < .001), diarrhea (p < .001), anorexia (p = .02), nausea (p < .01), anxiety (p < .001), and interference with life in general (p < .001). However, the control therapy significantly improved only 3 out of the 10 symptoms assessed; that is, abdominal pain-discomfort (p = .03), abdominal distension (p < .01), and interference with life (p = .01). Our results suggest that FT may have beneficial effects on intractable patients with IBS.
 ...
PMID:Effects of fasting therapy on irritable bowel syndrome. 1707 71

Blastocystis hominis (B. hominis) is a parasite of uncertain role in human disease. It may be identified during a workup for gastrointestinal symptoms, usually in stools. The clinical consequences of B. hominis infection are mainly diarrhea and abdominal pain as well as nonspecific gastrointestinal symptoms such as nausea, anorexia, vomiting, weight loss, lassitude, dizziness, and flatulence. Case reports and series have suggested a pathogenic role of B. hominis in causing intestinal inflammation. Also some studies have suggested that inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) are associated with B. hominis infection. The investigators indicate that the stools of all patients presenting with IBD or IBS should be examined, and culture methods for B. hominis carried out. Invasion and mucosal inflammation of the intestine with B. hominis have been observed in studies of gnotobiotic guinea pigs. The transmission, pathogenicity, culture characteristics, taxonomy, life cycle, biochemistry and molecular biology of B. hominis remain unclear. More studies are necessary for this parasite.
 ...
PMID:[Blastocystis hominis and bowel diseases]. 1710 62

Serotonin (5-HT) is most commonly thought of as a neurotransmitter in the central nervous system. However, the predominant site of serotonin synthesis, storage, and release is the enterochromaffin cells of the intestinal mucosa. Within the intestinal mucosa, serotonin released from EC cells activates neural reflexes associated with intestinal secretion, motility, and sensation. Two important receptors for serotonin that are located in the neural circuitry of the intestines are the 5-HT(3) and 5-HT(4) receptors; these are the targets of drugs designed to treat gastrointestinal disorders. 5-HT(3) receptor antagonists are used to treat nausea and emesis associated with chemotherapy and for functional disorders associated with diarrhea. 5-HT(4) receptor agonists are used as promotility agents to promote gastric emptying and to alleviate constipation. Because of the importance of serotonin in normal gut function and sensation, a number of studies have investigated potential changes in mucosal serotonin signaling in pathologic conditions. Despite the inconsistencies in the current literature, changes in serotonin signaling have now been demonstrated in inflammatory bowel disease, irritable bowel syndrome, postinfectious irritable bowel syndrome, and idiopathic constipation. Emerging evidence has led to many contradictory theories regarding serotonin signaling and its roles in the pathology of gut disorders. This review summarizes the current medications affecting serotonin signaling and provides an overview of our current knowledge of the changes in serotonin that occur in pathologic conditions.
 ...
PMID:Serotonin and its role in colonic function and in gastrointestinal disorders. 1719 2

Serotonin is an important gastrointestinal signaling molecule. It is a paracrine messenger utilized by enterochromaffin (EC) cells, which function as sensory transducers. Serotonin activates intrinsic and extrinsic primary afferent neurons to, respectively, initiate peristaltic and secretory reflexes and to transmit information to the central nervous system. Serotonin is also a neurotransmitter utilized by a system of long descending myenteric interneurons. Serotonin is synthesized through the actions of 2 different tryptophan hydroxylases, TpH1 and TpH2, which are found, respectively, in EC cells and neurons. Serotonin is inactivated by the serotonin reuptake transporter (SERT)-mediated uptake into enterocytes or neurons. The presence of many serotonin receptor subtypes enables selective drugs to be designed to therapeutically modulate gastrointestinal motility, secretion, and sensation. Current examples include tegaserod, a 5-HT(4) partial agonist, which has been approved for treatment of irritable bowel syndrome (IBS) with constipation in women and for chronic constipation in men and women. The 5-HT(3) antagonists, granisetron and ondansetron, are useful in combating the nausea associated with cancer chemotherapy, and alosetron is employed in the treatment of IBS with diarrhea. Serotonergic signaling abnormalities have also been putatively implicated in the pathogenesis of functional bowel diseases. Other compounds, for which efficacy has not been rigorously established, but which may have value, include tricyclic antidepressants and serotonin selective reuptake inhibitors to combat IBS, and 5-HT(1) agonists, which enhance gastric accommodation, to treat functional dyspepsia. The initial success encountered with serotonergic agents holds promise for newer and more potent insights and therapies of brain-gut disorders.
 ...
PMID:The serotonin signaling system: from basic understanding to drug development for functional GI disorders. 1724 88

Tegaserod, a selective and partial agonist at the 5-hydroxytryptamine (5-HT [serotonin]) receptor subtype 4 (5-HT4), is the only United States Food and Drug Administration-approved drug for the treatment of constipation-predominant irritable bowel syndrome (IBS) in women. The drug's stimulation of 5-HT4 receptors on intestinal enterocytes increases peristaltic activity and fluid secretion into the gut lumen, facilitating stool passage. In addition, affinity of tegaserod for 5-HT4 receptors modulates visceral sensitivity, which helps alleviate abdominal pain associated with constipation-predominant IBS. The drug's pharmacokinetic and pharmacodynamic parameters do not differ significantly with age or sex. Tegaserod safely and effectively relieves overall gastrointestinal symptoms and abdominal discomfort and normalizes bowel habits in patients with constipation-predominant IBS. It is associated with few drug interactions. In clinical studies, tegaserod was well tolerated, and its adverse-effect profile was similar to that of placebo. Severe diarrhea, as well as abdominal pain, flatulence, headache, and nausea, were the most commonly reported events. Patients who experience severe diarrhea should discontinue the drug. With the data available, tegaserod remains an option for patients with constipation-predominant IBS.
 ...
PMID:Tegaserod for constipation-predominant irritable bowel syndrome. 1725 16

The 5-HT3 receptor is a pentameric ligand-gated cation channel which is found in the central and peripheral nervous system and on extraneuronal locations like lymphocytes, monocytes and fetal tissue. Five monomer subtypes, the 5-HT(3A-E) subunits, have been identified which show differences in the amino-terminal and the transmembrane region. The functional relevance of different receptor compositions is not yet clarified. 5-HT3 receptors are located predominantly in CNS regions that are involved in the integration of the vomiting reflex, pain processing, the reward system and anxiety control. The preferential localization on nerve endings is consistent with a physiological role of 5-HT3 receptors in the control of neurotransmitter release such as dopamine, cholecystokinin, glutamate, acetylcholine, GABA, substance P, or serotonin itself. 5-HT3-receptor agonists cause unpleasant effects like nausea and anxiety, and no clinical use has been considered. In contrast, the introduction of 5-HT3-receptor antagonists for chemotherapy-induced vomiting was extremely successful. After development of other gastrointestinal indications like postoperative vomiting and diarrhea-predominant irritable bowel syndrome recent research focuses on rheumatological indications such as fibromyalgia, rheumatoid arthritis and tendinopathies. Positive effects have also been observed for pain syndromes such as chronic neuropathic pain and migraine. These effects seem to be related to substance P-mediated inflammation and hyperalgesia. Furthermore, antiinflammatory and immunomodulatory properties have been observed for 5-HT3-receptor antagonists which might explain promising findings in systemic sclerosis and other immunological conditions. For all of these innovative indications the optimal dosing schedule is a crucial issue, since a bell-shaped dose-response curve has been observed repeatedly for 5-HT3-receptor antagonists, particularly in CNS effects.
 ...
PMID:The neuronal 5-HT3 receptor network after 20 years of research--evolving concepts in management of pain and inflammation. 1731 6


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>