Pharmacologic and complementary and alternative medicine therapies for irritable bowel syndrome

2-Amino-N-Phenethylbenzamides for Irritable Bowel Syndrome Treatment

Irritable bowel syndrome (IBS) is a common gastrointestinal (GI) disorder characterized by abdominal pain or discomfort. Mebeverine is an antispasmodic that has been widely used in clinical practice to relieve the symptoms of IBS. However, its systemic use usually leads to side effects. Therefore, the current paper aimed to synthesize more effective medicines for IBS treatment. We used ring opening of isatoic anhydride for the synthesis in reaction with 2-phenylethylamine. In silico simulation predicted spasmolytic activity for 2-amino-N-phenethylbenzamides. The newly synthesized compounds demonstrated a relaxation effect similar to mebeverine but did not affect the serotonin or Ca2+-dependent signaling pathway of contractile activity (CA) in contrast. Having in mind the anti-inflammatory potential of antispasmodics, the synthesized molecules were tested in vitro and ex vivo for their anti-inflammatory effects. Four of the newly synthesized compounds demonstrated very good activity by preventing albumin denaturation compared to anti-inflammatory drugs/agents well-established in medicinal practice. The newly synthesized compounds also inhibited the expression of interleukin-1β and stimulated the expression of neuronal nitric oxide synthase (nNOS), and, consequently, nitric oxide (NO) synthesis by neurons of the myenteric plexus. This characterizes the newly synthesized compounds as biologically active relaxants, offering a cleaner and more precise application in pharmacological practice, thereby enhancing their potential therapeutic value.

Acupuncture for gastrointestinal diseases

Acupuncture, an important component of traditional Chinese medicine, has gained growing attention around the world in the past decades. Both manual and electroacupuncture are commonly used in clinical practice, especially by patients with gastrointestinal disorders seeking symptoms control due to disease signs recurrence and/or lack of effective treatments. Currently, patients with functional gastrointestinal disorders, constipation, gastroesophageal reflux disease, inflammatory bowel disease, ileus, acute pancreatitis, and gastroparesis may benefit from acupuncture treatment, as clinically evident, and the most frequently used acupoints are chosen from the large intestine, stomach, bladder, and spleen meridian. The underlying mechanisms of acupuncture involve the neuromodulation, adjustment of gastrointestinal motility and visceral hypersensitivity, anti-inflammation, repairment of gut microbiota, and intestinal barrier. As methodology advanced, cumulative number of well-designed clinical trials has been established, which might help elevating clinicians and gastroenterologists' awareness and perception toward application of acupuncture for gastrointestinal diseases management.

Parkinson's disease constipation effect of electroacupuncture at ST25 through colonic motility and enteric neuropathology

Background

The enteric nervous system (ENS) plays a central role in developing Parkinson's disease (PD) constipation, and the regulation of the ENS may be a key component in treating PD constipation. Electroacupuncture (EA) can effectively treat constipation symptoms in PD, but research on its specific mechanisms, especially in terms of ENS, is relatively lacking. Therefore, we investigated whether EA at ST25 promotes the restoration of ENS structure and colonic motor function in the rotenone-induced PD constipation rat model.

Methods

In this study, we evaluated constipation symptoms by stool characteristics, excretion and water volume, and whole gut transit time and observed colonic motility regulation through colonic motion detection and pathological changes in the colonic myenteric nervous plexus by transmission electron microscopy and immunofluorescence staining.

Results

EA significantly improved the constipation symptoms and positively adjusted the colonic motility in rotenone-induced PD constipation rats. At the same time, EA reversed the rotenone-induced colonic myenteric nervous plexus injury and regulated the ratio of inhibitory and excitatory neurotransmitters.

Conclusion

Our results indicate that EA treatment of PD constipation may be mediated through the adjustment of ENS.

A double-blind randomized clinical trial of Dracocephalum kotschyi Boiss. in the patients with diarrhea-predominant irritable bowel syndrome

Background and purpose

Irritable bowel syndrome (IBS) is a disease that shows its impacts on many populations worldwide. It is known as a functional disorder of the gastrointestinal tract followed by diarrhea and fecal inconsistency. Due to the lack of treatment in the allopathic medicine system for IBS, people in the western world use different herbs as alternative medicine. In the present study, we evaluated the dried extract of Dracocephalum kotschyi against IBS.

Experimental approach

In a randomized, double-blinded, placebo-controlled clinical trial, 76 diarrhea-predominant IBS patients were randomly assigned to two equal groups: the control group (given the placebo capsule containing 250 mg of dibasic calcium phosphate) and the treatment groups (given the capsule containing 75 mg of the dry extract of D. kotschyi and 175 mg of dibasic calcium phosphate as filler). The study was conducted based on Rome III criteria. We studied symptoms included in Rome III criteria and divided the study into the duration of drug administration and four weeks after drug administration. These groups were compared with those of the control group.

Findings/Results

Significant improvements were found in the quality of life, temperament, and IBS symptoms throughout the treatment duration. Quality of life, temperature, and IBS symptoms were slightly decreased in the treatment group 4 weeks after stopping the treatment. While concluding the study, we found D. kotschyi effective against IBS.

Conclusion and implications

Whole extract of D. kotschyi modulated symptoms of IBS patients and improved their quality of life.

Getting the guts to expand stroke treatment: The potential for microbiome targeted therapies

AIMS

This review focuses on the recent literature regarding the role of the gut-brain axis (GBA) following ischemic stroke.

DISCUSSION

Stroke is the 5th leading cause of death and disability in the United States; however, few therapies have been developed to improve prognoses. There is a plethora of evidence suggesting peripheral inflammatory responses play a large role in the pathogenesis of stroke. Additionally, hyperglycemic conditions may play a significant role in worsening stroke outcomes due to microbiome dysbiosis.

CONCLUSION

Recent research has illuminated the vital role of the GBA in propagating poor clinical outcomes, such as hemorrhagic transformation, following ischemic stroke. Considering this detrimental consequence of stroke, and the apparent role of the GBA role, future therapeutics should aim to mitigate this peripheral contribution to stroke complications.

Evaluation of a Multidisciplinary Integrated Treatment Approach Versus Standard Model of Care for Functional Gastrointestinal Disorders (FGIDS): A Matched Cohort Study

BACKGROUND

Functional gastrointestinal disorders (FGID) are linked to a variety of potential causes, and treatments include reassurance, life-style (including diet), psychological, or pharmacologic interventions.

AIMS

To assess whether a multidisciplinary integrated treatment approach delivered in a dedicated integrated care clinic (ICC) was superior to the standard model of care in relation to the gastrointestinal symptom burden.

METHODS

A matched cohort of 52 consecutive patients with severe manifestation of FGID were matched with 104 control patients based upon diagnosis, gender, age, and symptom severity. Patients in the ICC received structured assessment and 12-weeks integrated treatment sessions provided as required by gastroenterologist and allied health team. Control patients received standard medical care at the same tertiary center with access to allied health services as required but no standardized interprofessional team approach. Primary outcome was reduction in gastrointestinal symptom burden as measured by the Structured Assessment of Gastrointestinal Symptoms Scale (SAGIS). Secondary outcome was reduction in anxiety and depressive symptoms as measured by the Hospital Anxiety and Depression Scale (HADS).

RESULTS

Mixed models estimated the within ICC change in SAGIS total as -9.7 (95% CI -13.6, -5.8; p < 0.0001), compared with -1.7 (95% CI -4.0, 0.6; p = 0.15) for controls. The difference between groups reached statistical significance, -7.6 (95% CI -11.4, -3.8; p < 0.0001). Total HADS scores in ICC patients were 3.4 points lower post-intervention and reached statistical significance (p = 0.001).

CONCLUSION

This matched cohort study demonstrates superior short-term outcomes of FGID patients in a structured multidisciplinary care setting as compared to standard care.

Comparison of fluoxetine and duloxetine hydrochloride therapeutic effects on patients with constipation-predominant irritable bowel syndrome

Aim

As few randomized clinical trials have verified the efficacy of selective and norepinephrine reuptake inhibitors in IBS, the current study made an inclusive comparison between them, and their effectiveness in IBS-C was proven.

Background

Irritable bowel syndrome with constipation (IBS-C) is a functional bowel disorder characterized by changes in bowel movements and abdominal pain in the absence of identifiable structural abnormalities. Despite much progress in the treatment of other types of IBS, limited treatments are available for IBS-C.

Methods

The study population comprised 182 IBS-C patients who were randomly divided into 3 groups according to treatment type. One group was given 20 mg of dicyclomine and fluoxetine, the second group received dicyclomine along with duloxetine hydrochloride, and the third group received dicyclomine only for two months. The severity of symptoms was recorded by questionnaire at the beginning and end of the treatment.

Results

The average age and BMI of the patients were 28.5 ± 5.2 years and 25.2 ± 2.4 kg/m2, respectively. Duloxetine was more effective than fluoxetine in reducing flatulence (p=0.043), abdominal pain intensity (p≤0.046), and duration (p≤0.003), in increasing the quality of life (p≤0.046), and the frequency of fecal excretion in patients (p≤0.004).

Conclusion

Based on the study findings, fluoxetine and duloxetine had greater therapeutic effects on all symptoms of IBD than dicyclomine, with duloxetine, specifically, being more effective than fluoxetine. Further studies on larger groups are suggested to determine the best dosage and identify any potential side effects of these drugs.

Standardizing and optimizing acupuncture treatment for irritable bowel syndrome: A Delphi expert consensus study

BACKGROUND

Acupuncture has been widely utilized for irritable bowel syndrome (IBS). However, heterogeneity is large among therapeutic strategies and protocols. The aim of this study was to propose some down-to-earth recommendations and establish an optimized protocol for acupuncture practice in IBS.

METHODS

A panel of 74 traditional Chinese medicine (TCM) acupuncturists participated in clinical issue investigation. Subsequently, systematic reviews concerning acupuncture for IBS were screened within 3 databases. An initial consensus questionnaire was formed from the results of clinical issue investigation and literature review. Ultimately, a Delphi vote was carried out to determine these issues. 30 authoritative experts with extensive experience were requested to respond with agreement, neutrality, or disagreement for the items. Consensus achievement on a given item was defined as greater than 80% agreement.

RESULTS

Following a 2-round Delphi survey, there were 19 items reaching consensus; of which 5 items (26.32%) achieved thorough consensus, and significant agreement was reached for the other 14 items. These items can be classified into the 3 major domains: 1) clinical outcomes that acupuncture can bring for favorable intervention population (5 items), 2) suitable therapeutic principles and parameters of acupuncture (13 items), 3) possible adverse events in the treatment (1 item).

CONCLUSION

Without any ready-made guidelines and lacking of homogeneity in the published literatures, such expert consensus could be valuable for TCM acupuncturists in daily practice and patients with IBS to obtain appropriate and standardized acupuncture treatment. In addition, it also points out the clinical focus which need to be further explored in future trials.

Efficacy and safety of Hominis placenta pharmacopuncture on mild cognitive impairment: Randomized, double blind, placebo-controlled, multi-center trial

INTRODUCTION

Mild cognitive impairment (MCI) is cognitive decline which can be observed in a wide range of cognitive domains. It is considered as a prodromal stage of dementia; therefore, strategies for treatment are necessary, but current evidence is limited. Combining the memory enhancing effect of Hominis placenta (H placenta) and acupuncture elucidated separately in previous studies, efficacy of H placenta pharmacopuncture for treating MCI is anticipated.

METHODS

Thirty participants will be recruited. Male and female adults aged 50 to 80 who voluntarily participate in the trial, are diagnosed with MCI according to diagnostic and statistical manual of mental disorders-5 criteria, and have a Clinical Dementia Rating score 0.5 will be enrolled. Participants who meet the criteria will be randomly allocated to either pharmacopuncture group or control group. Participants will undergo H placenta pharmacopuncture or saline pharmacopuncture in GV20, ST36, and CV12 twice weekly for 8 weeks and will be evaluated a month after the last treatment. Primary outcome will be difference in mean change of Korean version of Montreal Cognitive Assessment scores between intervention group and control group. Cognition, mood, sleep quality and quality of life will be also assessed using other neuropsychological tests and questionnaires regarding depression, anxiety, sleep and quality of life.

DISCUSSION

Evaluating the efficacy and safety data obtained by assessing diverse aspects of patients with MCI will broaden the scope of MCI management and prevention of dementia progression.

TRIAL REGISTRATION

Clinical Research Information Service (KCT0005368), Registered 02 Sep 2020, https://cris.nih.go.kr/cris/en/search/search_result_st01.jsp?seq=16425.

Acupuncture inhibits neuroinflammation and gut microbial dysbiosis in a mouse model of Parkinson's disease

Growing evidences show that gut microbiota is associated with the pathogenesis of Parkinson's disease (PD) and the gut-brain axis can be promising target for the development of the therapeutic strategies for PD. Acupuncture has been used to improve brain functions and inflammation in neurological disorders such as PD, and to recover the gastrointestinal dysfunctions in various gastrointestinal disorders. Thus, we investigated whether acupuncture could improve Parkinsonism and gut microbial dysbiosis induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. First, we observed that acupuncture treatment at acupoints GB34 and ST36 could improve motor functions and comorbid anxiety in PD mice. Next, we found that acupuncture increased the levels of dopaminergic fibers and neurons in the striatum and the substantia nigra, respectively. Acupuncture also restored the overexpression of microglia and astrocyte as well as conversion of Bax and Bcl-2 expression in both the striatum and the substantia nigra, indicating that inflammatory responses and apoptosis were blocked by acupuncture. Additionally, via 16S rRNA sequence analysis, we observed that the relative abundance of 18 genera were changed in acupuncture-treated mice compared to the PD mice. Of them, Butyricimonas, Holdemania, Frisingicoccus, Gracilibacter, Phocea, and Aestuariispira showed significant correlations with anxiety as well as motor functions. Furthermore, the predicted functional analyses showed that acupuncture restored the physiology functions such as glutathione metabolism, methane metabolism, and PD pathway. In conclusion, we suggest that the effects of acupuncture on the enhanced motor function and the protection of the dopaminergic neurons may be associated with the regulation of the gut microbial dysbiosis and thus the inhibition of the neuroinflammation in the PD mice.

A Qualitative Study of the Experiences of Complementary and Alternative Medicine of Patients With IBS-C

The aim of this study was to examine the complementary and alternative medicine (CAM) experiences of patients with constipation irritable bowel syndrome (IBS-C). This qualitative study consisted of a total of 30 patients, who were admitted to a university hospital in Turkey. Data were collected using a descriptive questionnaire and a semistructured interview. Data analysis identified 5 main themes: (1) constipation-related difficulties experienced due to IBS, (2) the feeling that the CAM use is natural and useful, (3) the effect of the environmental stimuli in preferring the use of CAM, (4) the feeling that CAM is not negative and relieves, and (5) suggesting the CAM use. In conclusion, it was determined that all the patients with constipation IBS used various CAM methods. It may be recommended to raise the awareness of the patients by health care professionals about the CAM methods that may be useful.

Use of Evidence-Based Herbal Medicines for Patients with Functional Gastrointestinal Disorders: A Conceptional Framework for Risk-Benefit Assessment and Regulatory Approaches

BACKGROUND

Herbal or complementary medicines are frequently used for the treatment of patients with functional gastrointestinal disorders (FGID). Regulatory requirements for herbal therapies are inconsistent and, in many jurisdictions, herbal therapies are either self-, minimally- or unregulated.

AIM

To provide guidance for the appropriate and safe use of herbal medicines in patients with FGID patients with special consideration of the regulatory frameworks.

METHODS

A PubMed search of the literature was performed; relevant articles were included.

RESULTS

Similar to chemically defined therapies herbal medicines can cause adverse events. Thus, a risk-benefit appraisal should be undertaken for these therapies. While there is no disease specific mortality in FGID patients, patients with FGID who fail to respond to "empiric" chemically defined therapies undergo diagnostic and therapeutic measures that can be associated with appreciable morbidity and mortality. Thus, effective herbal treatments that subsequently reduce health-care utilization, reduce risks related to diagnostic or therapeutic measures that are initiated if no improvement of symptoms occurs. This "protective" effect of effective treatments for FGID needs to be taken in consideration when the risks and benefits of treatments are determined. In addition, standards that mirror regulations for chemically defined treatments should apply and the components of the respective preparations should undergo ongoing toxicological testing and rigorous quality assurance measures (including pharmacovigilance) applied.

CONCLUSIONS

Some herbal therapies offer significant benefits for patients with FGID. To ensure the safety of these treatments, the regulatory requirements should mirror requirements for chemically defined treatments.

A Qualitative Study of the Experiences of Complementary and Alternative Medicine Use in Patients With IBS-C

The aim of this study was to explore the experiences of complementary and alternative medicine (CAM) among patients with constipation irritable bowel syndrome (IBS-C). This qualitative study consisted of a total of 30 patients who were admitted to a university hospital in Turkey. Data were collected using a descriptive questionnaire and a semistructured interview. Data analysis identified 5 main themes: (1) the constipation-associated difficulties experienced because of IBS; (2) the feeling that CAM is natural and useful; (3) the effect of environmental stimuli in preferring the use of CAM; (4) the feeling that CAM is not negative and relieves symptoms; and (5) suggesting the use of CAM. In conclusion, it was determined that all the patients with IBS-C used various CAM methods. It may be recommended that health care professionals should raise awareness among patients about CAM methods that may be useful.

The Effect of Phloroglucinol in Patients With Diarrhea-predominant Irritable Bowel Syndrome: A Randomized, Double-blind, Placebo-controlled Trial

BACKGROUND/AIMS

We aim to evaluate the efficacy and safety of phloroglucinol in patients with diarrhea-predominant irritable bowel syndrome (IBS-D).

METHODS

Seventy-two patients with IBS-D who met Rome III criteria were 1:1 randomized in a parallel, double-blind design to receive phloroglucinol or placebo for 2 weeks. Patients were followed for 1 week after the end of treatment. The primary outcome was the proportion of responders, defined as those who answered "moderate or more of improvement" to the subject global assessment for at least 1 week of the 2-week treatment period. Secondary outcomes included the proportion of these patients during the 3-week period including 1 week of follow-up, IBS symptoms (abdominal pain/discomfort, diarrhea, urgency, mucus in stool, bloating, and passage of gas), stool frequency and consistency, and IBS quality of life (IBS-QOL).

RESULTS

The proportion of responders during 2-week treatment period tended to be higher in the phloroglucinol group than in the placebo group, although the difference did not reach statistical significance (55.6% vs 30.6%, P = 0.056). The proportion of responders during the 3-week period was significantly higher in the phloroglucinol group than in the placebo group (61.6% vs 30.6%, P = 0.013). Individual symptom scores, IBS-QOL, stool frequency and consistency tended to improve in the phloroglucinol group, but there were no statistical significances compared to those of the placebo group. No serious adverse events were reported in both groups.

CONCLUSIONS

Phloroglucinol could be a safe and beneficial option for the management of overall IBS symptoms in patients with IBS-D. Further large scaled studies are warranted.

Alosetron versus traditional pharmacotherapy in clinical practice: effects on resource use, health-related quality of life, safety and symptom improvement in women with severe diarrhea-predominant irritable bowel syndrome

OBJECTIVE

Severe diarrhea-predominant irritable bowel syndrome (IBS-D) is associated with decreased health-related quality of life (HRQOL) and increased health care costs. Treatment recommendations for IBS-D often start with traditional pharmacotherapy (TP), with escalation to alosetron, rifaximin or eluxadoline if there is no success. There has been no previous head-to-head clinical trial comparing IBS-D treatment outcome for alosetron versus TP. This study, GSK protocol S3B30020, evaluated resource use, work productivity, health-related quality of life and global symptom response in women with IBS-D who were treated with alosetron or TP.

METHODS

A total of 1956 patients who met criteria for severe IBS-D were randomized to treatment with alosetron 1 mg twice daily (BID) or only TP for up to 24 weeks. Work productivity and resource use were evaluated by standard questionnaires, HRQOL by the IBSQOL instrument and IBS symptoms by the Global Improvement Scale (GIS).

RESULTS

Compared to only TP, alosetron-treated patients reported: (1) fewer clinic/office visits for any health problem (p = .0181) or for IBS-D (p = .0004); (2) reduced use of over-the-counter medications for IBS-D (p < .0001); (3) fewer days of lost work productivity (p < .0001); (4) decreased restriction of social and outdoor activities (p < .0001); and (5) greater global improvement in IBS-D symptoms (p < .0001). Alosetron treatment improved HRQOL scores for all domains (p < .0001). Incidence of adverse events during alosetron use was not remarkable and was similar to that previously reported.

CONCLUSIONS

Alosetron 1 mg BID significantly reduced health care utilization and lost productivity, and significantly improved global IBS symptoms, HRQOL, and participation in outdoor and social activities compared with treatment response to TP.

The Efficacy of Acceptance and Commitment Therapy (ACT) Matrix on Depression and Psychological Capital of the Patients with Irritable Bowel Syndrome

BACKGROUND:

Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders, worldwide. Psychological disorders are common among patients with IBS.

AIM:

This study aims to investigate the efficacy of acceptance and commitment therapy (ACT) matrix on depression and psychological capital of patients with IBS.

MATERIAL AND METHODS:

In a quasi-experimental study, a total number of 30 patients with IBS were selected using convenience sampling. Those patients who meet the inclusion criteria were randomly assigned to control and experimental groups (15 patients in each group). Data were collected using the Beck Depression Inventory (BDI) and the Psychological Capital Questionnaire (PCQ). The experimental group was subjected to the acceptance and commitment therapy (ACT) amtrix, but the control group do not receive this treatment. Questionnaires were completed before (pre-test) and after (post-test) the intervention by patients in two groups. All patients in two groups responded to the questionnaires and returned them to the researcher. Data were analyzed using chi-square test, independent t-test, analysis of covariance (ANCOVA) and multivariate analysis of covariance (MANCOVA).

RESULTS:

Analyzing the data showed that there were significant differences regarding depression and psychological capital between experimental and control group, before and after the study (p < 0.05).

CONCLUSION:

Using ACT matrix is a useful modality to improve the depression and psychological capital among patients with IBS.

Understanding symptom burden and attitudes to irritable bowel syndrome with diarrhoea: Results from patient and healthcare professional surveys

BACKGROUND

Irritable bowel syndrome with diarrhoea (IBS-D) comprises multiple troublesome symptoms and negatively impacts patients' quality of life.

OBJECTIVE

The objective of this article is to assess IBS-D patient burden and patient and healthcare professional (HCP) attitudes towards IBS.

METHODS

Patients and HCPs from Australia, Canada, France, Germany, Italy, Spain and the United Kingdom completed internet-based surveys via market research panels. Attitudes to IBS-D-related statements were scored using seven-point Likert scales.

RESULTS

The patient survey included 513 patients (70% female, mean age 40.9 years). Faecal urgency was reported as the most troublesome symptom (27%) and fatigue occurred on the most days per month (mean: 18); 61% of patients used ≥3 types of treatment daily or intermittently; 19% used antidepressants daily. Thirty-three per cent thought HCPs should listen and provide more support and 46% reported willingness to 'try anything' to help manage their IBS-D. The HCP survey included 366 primary care physicians and 313 gastroenterologists: A total of 70% and 65%, respectively, agreed it was important that IBS-D patients feel listened to and supported; 73% agreed their main aim was to improve quality of life; ∼30% expressed frustration at managing IBS-D.

CONCLUSION

IBS-D imposes a substantial burden on patients and HCPs. These findings point towards a need for improved patient-HCP communication.

Gastrointestinal and Hepatic Disease in Fibromyalgia

Fibromyalgia (FM) has historically been associated with several diseases in gastroenterology and hepatology. The most substantiated evidence pertains to irritable bowel syndrome (IBS). The pathogeneses of FM and IBS remain unclear, but it is likely related to dysregulation within the brain-gut axis, resulting in a hyperalgesic state. IBS and FM share other similarities, including a female predominance, fatigue, insomnia, and susceptibility to psychiatric state. These common manifestations and pathogeneses serve as a foundation for overlapping, multidisciplinary treatment modalities.

Small Intestinal Bacterial Overgrowth and Irritable Bowel Syndrome: A Bridge between Functional Organic Dichotomy

The pathogenesis of irritable bowel syndrome (IBS), once thought to be largely psychogenic in origin, is now understood to be multifactorial. One of the reasons for this paradigm shift is the realization that gut dysbiosis, including small intestinal bacterial overgrowth (SIBO), causes IBS symptoms. Between 4% and 78% of patients with IBS and 1% and 40% of controls have SIBO; such wide variations in prevalence might result from population differences, IBS diagnostic criteria, and, most importantly, methods to diagnose SIBO. Although quantitative jejunal aspirate culture is considered the gold standard for the diagnosis of SIBO, noninvasive hydrogen breath tests have been popular. Although the glucose hydrogen breath test is highly specific, its sensitivity is low; in contrast, the early-peak criteria in the lactulose hydrogen breath test are highly nonspecific. Female gender, older age, diarrhea-predominant IBS, bloating and flatulence, proton pump inhibitor and narcotic intake, and low hemoglobin are associated with SIBO among IBS patients. Several therapeutic trials targeting gut microbes using antibiotics and probiotics have further demonstrated that not all symptoms in patients with IBS originate in the brain but rather in the gut, providing support for the micro-organic basis of IBS. A recent proof-of-concept study showing the high frequency of symptom improvement in patients with IBS with SIBO further supports this hypothesis.

Sham acupuncture is as efficacious as true acupuncture for the treatment of IBS: A randomized placebo controlled trial

BACKGROUND

Irritable bowel syndrome (IBS) patients increasingly seek out acupuncture therapy to alleviate symptoms, but it is unclear whether the benefit is due to a treatment-specific effect or a placebo response. This study examined whether true acupuncture is superior to sham acupuncture in relieving IBS symptoms and whether benefits were linked to purported acupuncture mechanisms.

METHODS

A double blind sham controlled acupuncture study was conducted with Rome I IBS patients receiving twice weekly true acupuncture for 4 weeks (n=43) or sham acupuncture (n=36). Patients returned at 12 weeks for a follow-up review. The primary endpoint of success as determined by whether patients met or exceeded their established goal for percentage symptom improvement. Questionnaires were completed for symptom severity scores, SF-36 and IBS-36 QOL tools, McGill pain score, and Pittsburg Sleep Quality Index. A subset of patients underwent barostat measurements of rectal sensation at baseline and 4 weeks.

KEY RESULTS

A total of 53% in the true acupuncture group met their criteria for a successful treatment intervention, but this did not differ significantly from the sham group (42%). IBS symptom scores similarly improved in both groups. Scores also improved in the IBS-36, SF-36, and the Pittsburg Sleep Quality Index, but did not differ between groups. Rectal sensory thresholds were increased in both groups following treatment and pain scores decreased; however, these changes were similar between groups.

CONCLUSIONS & INFERENCES

The lack of differences in symptom outcomes between sham and true treatment acupuncture suggests that acupuncture does not have a specific treatment effect in IBS.

TummyTrials: A Feasibility Study of Using Self-Experimentation to Detect Individualized Food Triggers

Diagnostic self-tracking, the recording of personal information to diagnose or manage a health condition, is a common practice, especially for people with chronic conditions. Unfortunately, many who attempt diagnostic self-tracking have trouble accomplishing their goals. People often lack knowledge and skills needed to design and conduct scientifically rigorous experiments, and current tools provide little support. To address these shortcomings and explore opportunities for diagnostic self-tracking, we designed, developed, and evaluated a mobile app that applies a self-experimentation framework to support patients suffering from irritable bowel syndrome (IBS) in identifying their personal food triggers. TummyTrials aids a person in designing, executing, and analyzing self-experiments to evaluate whether a specific food triggers their symptoms. We examined the feasibility of this approach in a field study with 15 IBS patients, finding that participants could use the tool to reliably undergo a self-experiment. However, we also discovered an underlying tension between scientific validity and the lived experience of self-experimentation. We discuss challenges of applying clinical research methods in everyday life, motivating a need for the design of self-experimentation systems to balance rigor with the uncertainties of everyday life.

Irritable Bowel Syndrome: Clinical Manifestations, Dietary Influences, and Management

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder that is characterized by symptoms of chronic abdominal pain and altered bowel habits in the absence of an overtly identifiable cause. It is the most commonly diagnosed functional gastrointestinal disorder, accounting for about one third of gastroenterology visits. It generally presents as a complex of symptoms, including psychological dysfunction. Hypersensitivity to certain foods, especially foods that contain high amounts of fructose, plays a role in the pathophysiology of IBS. Elevated consumption of high-fructose corn syrup (HFCS) has been discussed in this aspect. The treatment options for IBS are challenging and varied. In addition to dietary restrictions for HFCS-induced IBS, such as low-FODMAP (Fermentable Oligosaccharides, Disaccharide, Monosaccharides, and Polyols) diets, existing drug therapies are administered based on the predominant symptoms and IBS-subtype. Patients with IBS are likely to suffer from issues, such as anxiety, depression, and post-traumatic-stress disorder. Biopsychosocial factors particularly socioeconomic status, sex, and race should, thus, be considered for diagnostic evaluation of patients with IBS.

Current and emergent pharmacologic treatments for irritable bowel syndrome with diarrhea: evidence-based treatment in practice

Irritable bowel syndrome with diarrhea (IBS-D) is a common, chronic functional gastrointestinal disorder with symptoms that can be distressing for patients and often result in substantially impaired quality of life. This review focuses on providing clinicians with information on practical, evidence-based treatment for IBS-D. Current therapies commonly used for the treatment of IBS-D, including pharmacologic and nonpharmacologic interventions, are briefly reviewed, followed by discussion of the emergent pharmacologic treatments (rifaximin and eluxadoline) and medical foods (IBgard® and EnteraGam®). Given the lack of a standard treatment algorithm for IBS-D and the emergence of new pharmacologic therapies, treatment needs to be tailored to the individual patient and take into account the severity of disease. In this context, the latter part of this manuscript examines how treatments for IBS-D can be used in clinical practice by presenting three patient case scenarios with varying degrees of IBS-D severity. For each case, the patient's medical history and clinical presentation are related to the Rome Foundation multidimensional clinical profile (MDCP) and potential treatment options with current and emergent therapies are reviewed. The interplay of gastrointestinal symptoms and their psychosocial impact, as well as the importance of a patient-centered approach to therapy, are discussed. Consideration is given to the potential need for combination therapies and how emergent treatments could fit into the treatment pathway for mild, moderate, and severe cases of IBS-D in clinical practice.

Acupuncture for chronic diarrhea in adults: Protocol for a systematic review

BACKGROUND

As 2 major common types of chronic diarrhea, functional diarrhea (FD) and diarrhea-predominant irritable bowel syndrome (IBS-D) affect 1.54% to 1.72% of people in China. Acupuncture is commonly used in clinical practice for patients with chronic diarrhea. Here, we present a protocol of systematic review aimed at systematically review all the clinical evidence on the effectiveness of acupuncture for treating FD and IBS-D in adults.

METHODS

The review will be performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement. We will search the following databases from their inception to January 2017: Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, China Biology Medicine disc, Wan-Fang Data, China National Knowledge Infrastructure, Citation Information by National Institute of Informatics, Oriental Medicine Advanced Searching Integrated System by Korea Institute of Oriental Medicine, and Japan Science and Technology Information Aggregator (J-stage). Clinical trial registrations will also be searched. Primary outcome measures are the change of bowel movements. The secondary outcomes include stool consistency, quality of life scales, other standardized rating scales, patient satisfaction, and acupuncture-related adverse effects assessment.

ETHICS AND DISSEMINATION

This review does not require ethical approval and will be disseminated electronically or in print.

PROSPERO REGISTRATION NUMBER

CRD42015017574.

Polyunsaturated Fatty Acids and Their Derivatives: Therapeutic Value for Inflammatory, Functional Gastrointestinal Disorders, and Colorectal Cancer

Polyunsaturated fatty acids (PUFAs) are bioactive lipids which modulate inflammation and immunity. They gained recognition in nutritional therapy and are recommended dietary supplements. There is a growing body of evidence suggesting the usefulness of PUFAs in active therapy of various gastrointestinal (GI) diseases. In this review we briefly cover the systematics of PUFAs and their metabolites, and elaborate on their possible use in inflammatory bowel disease (IBD), functional gastrointestinal disorders (FGIDs) with focus on irritable bowel syndrome (IBS), and colorectal cancer (CRC). Each section describes the latest findings from in vitro and in vivo studies, with reports of clinical interventions when available.

Lack of Association Found between Helicobacter pylori Infection and Diarrhea-Predominant Irritable Bowel Syndrome: A Multicenter Retrospective Study

Aims. The association between Helicobacter pylori (H. pylori) infection and diarrhea-predominant irritable bowel syndrome (IBS-D) is still controversial. Here we performed a retrospective study to explore this issue. Methods. A total of 502 inpatients with Rome III confirmed IBS-D and known H. pylori status from 8 hospitals were enrolled. H. pylori-positive patients, hospitalized in the recent year, were followed up to evaluate the effects of H. pylori eradication on IBS-D clinical course. Results. Of the 502 IBS-D patients, 206 were H. pylori-positive, with an infection rate that has no significant difference with that of the general population in Guangdong province (p = 0.348). For patients followed up, no significant differences were noted as to overall symptoms (p = 0.562), abdominal pain/discomfort (p = 0.777), bloating (p = 0.736), stool frequency (p = 0.835), or stool characteristics (p = 0.928) between the H. pylori-eradicated group and the control group. The results were the same in long-term follow-up patients except the improvement of bloating, which showed that the bloating score in the H. pylori-eradicated group was significantly lower (p = 0.047). Conclusions. No significant correlation between H. pylori infection and IBS-D was noted. Overall, IBS-D patients may not benefit from H. pylori eradication.

Novel investigational drugs for constipation-predominant irritable bowel syndrome: a review

INTRODUCTION

Constipation-predominant irritable bowel syndrome (IBS-C) is a functional gastrointestinal (GI) disorder with an unknown etiology. A number of the drugs tested for IBS-C have also been applied to chronic constipation and chronic idiopathic constipation. Unfortunately, due to severe adverse effects, many drugs envisioned for IBS-C had been withdrawn from the market. Nevertheless, a number of potential new agents for this indication are now under development.

AREAS COVERED

The following review describes the most recently developed agents in preclinical as well as Phase 1 and Phase 2 clinical studies. Information was obtained from published literature, abstracts and the latest results found in Clinicaltrial.gov database. The authors put a special interest on glucagon-like peptide 1 analogue, bile acid modulators, serotonergic agents, guanylate cyclase C and cannabinoid antagonists.

EXPERT OPINION

To enter the market, a newly-developed drug has to meet several criteria, such as good bioavailability or the absence of drug-related adverse events. Taking into account constipation and abdominal pain as the main symptoms in IBS-C, a novel successful drug is usually able to improve both at the same time. Four out of fifteen investigational drugs described in this paper belong to the serotonergic family and have a good prognosis to reach the market; still, more long-term clinical studies are warranted.

What about OMT and nutrition for managing the irritable bowel syndrome? An overview and treatment plan

A chronic continuous or intermittent gastrointestinal tract dysfunction, the irritable bowel syndrome (IBS), appears to be due to dysregulation of brain-gut-microbiota communication. Furthermore, the "microbiota" greatly impacts the bi-directional brain-gut axis communication. This article describes IBS in relation to similar diseases, presents the background to osteopathy, and proposes osteopathic manipulative treatment (OMT) to manage IBS. In IBS, OMT focuses on the nervous and circulatory systems, spine, viscera, and thoracic and pelvic diaphragms in order to restore homeostatic balance, normalize autonomic activity in the intestine, promote lymphatic flow, and address somatic dysfunction. Lymphatic and venous congestion are treated by the lymphatic pump techniques and stimulation of Chapman׳s reflex points. A simple treatment plan designed to lessen chronic pain and inflammation in IBS is presented based on current evidence-based literature. Since food itself, food allergies, and intolerance could contribute to symptom onset or even cause IBS, this article also provides dietary modifications to consider for patients.

Comparative pharmacokinetics of rhein in normal and loperamide-induced constipated rats and microarray analysis of drug-metabolizing genes

ETHNOPHARMACOLOGICAL RELEVANCE

Rhein is a pharmacological active component found in Rheum palmatum L. that is the major herb of the San-Huang-Xie-Xin-Tang (SHXXT), a medicinal herbal product used as a remedy for constipation. Here we have investigated the comparative pharmacokinetics of rhein in normal and constipated rats. Microarray analysis was used to explore whether drug-metabolizing genes will be altered after SHXXT treatment.

MATERIALS AND METHODS

The comparative pharmacokinetics of rhein in normal and loperamide-induced constipated rats was studied by liquid chromatography with electrospray ionization tandem mass spectrometry (LC-MS/MS). Gene expression profiling in drug-metabolizing genes after SHXXT treatment was investigated by microarray analysis and real-time polymerase chain reaction (RT-PCR).

RESULTS

A validated LC-MS/MS method was applied to investigate the comparative pharmacokinetics of rhein in normal and loperamide-induced constipated rats. The pharmacokinetic results demonstrate that the loperamide-induced constipation reduced the absorption of rhein. Cmax significantly reduced by 2.5-fold, the AUC decreased by 27.8%; however, the elimination half-life (t1/2) was prolonged by 1.6-fold. Tmax and mean residence time (MRT) were significantly prolonged by 2.8-fold, and 1.7-fold, respectively. The volume of distribution (Vss) increased by 2.2-fold. The data of microarray analysis on gene expression indicate that five drug-metabolizing genes, including Cyp7a1, Cyp2c6, Ces2e, Atp1b1, and Slc7a2 were significantly altered by the SHXXT (0.5 g/kg) treatment.

CONCLUSION

The loperamide-induced constipation reduced the absorption of rhein. Since among the 25,338 genes analyzed, there were five genes significantly altered by SHXXT treatment. Thus, information on minor drug-metabolizing genes altered by SHXXT treatment indicates that SHXXT is relatively safe for clinical application.

The use of non-narcotic pain medication in pediatric gastroenterology

The perception of pain in children is easily influenced by environmental factors and psychological comorbidities that are known to play an important role in its origin and response to therapy. Chronic abdominal pain is one of the most commonly treated conditions in modern pediatric gastroenterology and is the hallmark of 'functional' disorders that include irritable bowel syndrome, functional dyspepsia, and functional abdominal pain. The development of pharmacological therapies for these disorders in adults and children has been limited by the lack of understanding of the putative, pathophysiological mechanisms that underlie them. Peripheral and central pain-signaling mechanisms are known to be involved in chronic pain originating from the gastrointestinal tract, but few therapies have been developed to target specific pathways or enhance correction of the underlying pathophysiology. The responses to therapy have been variable, potentially reflecting the heterogeneity of the disorders for which they are used. Only a few small, randomized clinical trials have evaluated the benefit of pain medications for chronic abdominal pain in children and thus, the decision on the most appropriate treatment is often based on adult studies and empirical data. This review discusses the most common, non-narcotic pharmacological treatments for chronic abdominal pain in children and includes a thorough review of the literature to support or refute their use. Because of the dearth of pediatric studies, the focus is on pharmacological and alternative therapies where there is sufficient evidence of benefit in either adults or children with chronic abdominal pain.

Serotonin, tryptophan metabolism and the brain-gut-microbiome axis

The brain-gut axis is a bidirectional communication system between the central nervous system and the gastrointestinal tract. Serotonin functions as a key neurotransmitter at both terminals of this network. Accumulating evidence points to a critical role for the gut microbiome in regulating normal functioning of this axis. In particular, it is becoming clear that the microbial influence on tryptophan metabolism and the serotonergic system may be an important node in such regulation. There is also substantial overlap between behaviours influenced by the gut microbiota and those which rely on intact serotonergic neurotransmission. The developing serotonergic system may be vulnerable to differential microbial colonisation patterns prior to the emergence of a stable adult-like gut microbiota. At the other extreme of life, the decreased diversity and stability of the gut microbiota may dictate serotonin-related health problems in the elderly. The mechanisms underpinning this crosstalk require further elaboration but may be related to the ability of the gut microbiota to control host tryptophan metabolism along the kynurenine pathway, thereby simultaneously reducing the fraction available for serotonin synthesis and increasing the production of neuroactive metabolites. The enzymes of this pathway are immune and stress-responsive, both systems which buttress the brain-gut axis. In addition, there are neural processes in the gastrointestinal tract which can be influenced by local alterations in serotonin concentrations with subsequent relay of signals along the scaffolding of the brain-gut axis to influence CNS neurotransmission. Therapeutic targeting of the gut microbiota might be a viable treatment strategy for serotonin-related brain-gut axis disorders.

Emerging role of probiotics and antimicrobials in the management of irritable bowel syndrome

OBJECTIVE

To review the potential role of probiotics and antimicrobials for management of functional bowel disorders (FBDs), with a focus on irritable bowel syndrome (IBS).

RESEARCH DESIGN AND METHODS

Relevant adult data were identified via PubMed, with additional references obtained by reviewing bibliographies from selected articles.

RESULTS

Probiotic treatment involves colonizing the intestines with beneficial microorganisms, whereas antimicrobial therapy involves modulation of the bacterial load and/or host response. A meta-analysis reported that all probiotic species evaluated improved flatulence compared with placebo; some, but not all, species improved abdominal pain and abdominal bloating/distension; and no species evaluated improved stool frequency or consistency, straining during stool evacuation, sense of incomplete evacuation, or fecal urgency. Two additional meta-analyses reported that probiotics significantly improved overall IBS symptoms. Individual studies have demonstrated potential benefits of probiotics for functional constipation symptoms. The nonsystemic antimicrobials neomycin and rifaximin have been evaluated in patients with IBS and other FBDs. Neomycin may improve global IBS symptoms and provide bowel normalization versus placebo, but the risk of ototoxicity and the development of clinically relevant bacterial resistance may limit its use for recurrent symptoms. In phase 3 randomized studies, rifaximin-treated patients were significantly more likely than placebo-treated patients to achieve adequate relief of global IBS symptoms and abdominal bloating. Although preliminary data suggest that development of clinically relevant bacterial resistance is unlikely with rifaximin, prospective data are needed, and a phase 3 study is ongoing. Limitations of evidence for probiotics include small populations analyzed and lack of clarity in optimal dosing regimen; antimicrobial evidence would benefit from better understanding of the effects of repeated treatment in patients with IBS.

CONCLUSIONS

Probiotics and nonsystemic antibiotics have a place in IBS management. Additional studies are needed to establish optimal regimens and identify subgroups of patients most likely to benefit from these therapies.

The microbiota-gut-brain axis in functional gastrointestinal disorders

Functional gastrointestinal disorders (FGIDs) are highly prevalent and pose a significant burden on health care and society, and impact patients' quality of life. FGIDs comprise a heterogeneous group of disorders, with unclear underlying pathophysiology. They are considered to result from the interaction of altered gut physiology and psychological factors via the gut-brain axis, where brain and gut symptoms are reciprocally influencing each other's expression. Intestinal microbiota, as a part of the gut-brain axis, plays a central role in FGIDs. Patients with Irritable Bowel Syndrome, a prototype of FGIDs, display altered composition of the gut microbiota compared with healthy controls and benefit, at the gastrointestinal and psychological levels, from the use of probiotics and antibiotics. This review aims to recapitulate the available literature on FGIDs and microbiota-gut-brain axis.

Determination of bioactive components in Chinese herbal formulae and pharmacokinetics of rhein in rats by UPLC-MS/MS

Rhein (4,5-dihydroxy-9,10-dioxoanthracene-2-carboxylic acid, cassic acid) is a pharmacological active component found in Rheum palmatum L. the major herb of San-Huang-Xie-Xin-Tang (SHXXT), a medicinal herbal product used as a remedy for constipation. Here we have determined multiple bioactive components in SHXXT and investigated the comparative pharmacokinetics of rhein in rats. A sensitive and specific method combining liquid chromatography with electrospray ionization tandem mass spectrometry has been developed and validated to simultaneously quantify six active compounds in the pharmaceutical herbal product SHXXT to further study their pharmacokinetics in rats. Multiple reaction monitoring (MRM) was employed for quantification with switching electrospray ion source polarity between positive and negative modes in a single run. There were no significant matrix effects in the quantitative analysis and the mean recovery for rhein in rat plasma was 91.6%±3.4%. The pharmacokinetic data of rhein demonstrate that the herbal formulae or the single herbal extract provide significantly higher absorption rate than the pure compound. This phenomenon suggests that the other herbal ingredients of SHXXT and rhubarb extract significantly enhance the absorption of rhein in rats. In conclusion, the herbal formulae (SHXXT) are more efficient than the single herb (rhubarb) or the pure compound (rhein) in rhein absorption.

Randomized clinical trial: macrogol/PEG 3350 plus electrolytes for treatment of patients with constipation associated with irritable bowel syndrome

OBJECTIVES

Polyethylene glycol (PEG) 3350 plus electrolytes (PEG 3350+E) is an established treatment for constipation and has been proposed as a treatment option for constipation associated with irritable bowel syndrome (IBS-C). This study aimed to compare the efficacy and safety of PEG 3350+E vs. placebo in adult patients with IBS-C.

METHODS

Following a 14-day run-in period without study medication, patients with confirmed IBS-C were randomized to receive PEG 3350+E (N=68) or placebo (N=71) for 28 days. The primary endpoint was the mean number of spontaneous bowel movements (SBMs) per day in the last treatment week.

RESULTS

In both groups, mean weekly number of SBMs (±s.d.) increased from run-in. The difference between the groups in week 4 (PEG 3350+E, 4.40±2.581; placebo, 3.11±1.937) was statistically significant (95% confidence interval: 1.17, 1.95; P<0.0001). Although mean severity score for abdominal discomfort/pain was significantly reduced compared with run-in with PEG 3350+E, there was no difference vs. placebo. Spontaneous complete bowel movements, responder rates, stool consistency, and severity of straining also showed superior improvement in the PEG 3350+E group over placebo in week 4. The most common drug related treatment-emergent adverse events were abdominal pain (PEG 3350+E, 4.5%; placebo, 0%) and diarrhoea (PEG 3350+E, 4.5%; placebo, 4.3%).

CONCLUSIONS

In IBS-C, PEG 3350+E was superior to placebo for relief of constipation, and although a statistically significant improvement in abdominal discomfort/pain was observed compared with baseline, there was no associated improvement compared with placebo. PEG 3350+E is a well-established and effective treatment that should be considered suitable for use in IBS-C.

Randomised clinical trial: symptoms of the irritable bowel syndrome are improved by a psycho-education group intervention

BACKGROUND

Evidence supports the effectiveness of cognitive behavioural approaches in improving the symptoms of the irritable bowel syndrome (IBS). Duration, cost and resistance of many patients towards a psychological therapy have limited their acceptance.

AIM

To evaluate the effectiveness of a psycho-educational intervention on IBS symptoms.

METHODS

Sixty-nine IBS patients (72% female) were randomised to an intervention or a wait-list control group. The IBS class consisted of education on a biological mind body disease model emphasising self-efficacy and practical relaxation techniques.

RESULTS

Patients in the intervention showed significant improvement on GI symptom severity, visceral sensitivity, depression and QoL postintervention and most of these gains were maintained at 3-month follow-up (Hedge's g = -0.46-0.77). Moderated mediation analyses indicated change in anxiety, visceral sensitivity, QoL and catastrophising due to the intervention had moderate mediation effects (Hedge's g = -0.38 to -0.60) on improvements in GI symptom severity for patients entering the trial with low to average QoL. Also, change in GI symptom severity due to the intervention had moderate mediation effects on improvements in QoL especially in patients with low to average levels of QoL at baseline. Moderated mediation analyses indicated mediation was less effective for patients entering the intervention with high QoL.

CONCLUSIONS

A brief psycho-educational group intervention is efficacious in changing cognitions and fears about the symptoms of the irritable bowel syndrome, and these changes are associated with clinically meaningful improvement in symptoms and quality of life. The intervention seems particularly tailored to patients with low to moderate quality of life baseline levels.

Microencapsulated sodium butyrate reduces the frequency of abdominal pain in patients with irritable bowel syndrome

AIM

Abdominal pain, defaecation disorder and change of bowel habit are the commonest symptoms of irritable bowel syndrome (IBS). The effect of microencapsulated sodium butyrate (MSB) was assessed on the severity of symptoms in patients with IBS.

METHOD

Sixty-six patients treated with one of the standard pharmacological therapies for at least 3 months were included in the study. They were randomized to receive MSB as a supplemental treatment to standard therapy or to receiving a placebo. Previous pharmacological therapy was continued throughout the study in both arms. Clinical evaluation was performed at baseline, 4 and 12 weeks. Each assessment was documented by a validated visual analogue score questionnaire measuring the severity of selected clinical symptoms, a closed-end questionnaire measuring the frequency of selected clinical symptoms and a single closed-end question measuring the subjective improvement of symptoms.

RESULTS

After 4 weeks there was a significant decrease of pain during defaecation in the MSB group which extended to improvement of urgency and bowel habit at 12 weeks. Reduction of abdominal pain, flatulence and disordered defaecation was not statistically significant.

CONCLUSIONS

MSB as a supplemental therapy can reduce the frequency of selected clinical symptoms in patients with IBS, without significant influence on reducing symptom severity.

Metabolic and toxicological considerations for the latest drugs used to treat irritable bowel syndrome

INTRODUCTION

The high prevalence of irritable bowel syndrome (IBS), a chronic gastrointestinal (GI) disorder, its lack of satisfactory effective drugs and its complicated pathophysiology lead to the demand of new therapeutic agents. During a new drug development process, the pharmacokinetic profiling is of a great considerable importance comparable to drug's efficacy. This involves the drug's absorption, distribution, metabolism and excretion, all of which are crucial to its usefulness. In addition, the toxicological profile and possible adverse reactions of the drug should be identified. Also its interactions should be identified at different phases of trials. Several pharmacokinetic studies are carried out to achieve drugs with the best absorption and bioavailability and the least adverse effects and lowest toxicity.

AREAS COVERED

To make an update on new clinically introduced drugs for IBS and their dynamics and kinetics data, the present systematic review was accomplished. All relevant bibliographic databases were searched from the year 2003 up to May 2012 to identify all clinical trials that evaluated the potential efficacy of a novel agent in IBS.

EXPERT OPINION

Some evaluated drugs, such as ramosetron (5-HT3 antagonist) and pexacerfont (CRF1 receptor antagonist), have shown some benefits in diarrhea-predominant IBS (D-IBS), while, prucalopride and mosapride (5-HT4 agonist) with prokinetic effect were found useful in constipation-predominant IBS (C-IBS). Besides, dexloxiglumide, lubiprostone and linaclotide have shown beneficial effects in C-IBS patients. Melatonin regulates GI tract motility and, asimadoline, gabapentin and pregabalin show reduction of pain threshold and visceral hypersensitivity. Glucagon-like peptide analog, calcium-channel blockers and neurokinin receptor antagonists have shown benefits in pain attacks. More time is required to indicate both efficacy and safety in long-term treatment due to multifactorial pathophysiology, variations in individual responses and insufficient assessment methods, which limit the right decision-making process about the efficacy and tolerability of these new drugs.

Effect and mechanism of acupuncture on gastrointestinal diseases

Acupuncture modulates various biomechanical responses, such as prokinetic, antiemetic, and antinociceptive effects. Acupuncture treatment involves the insertion of thin needles into the skin and underlying muscle and the needles are stimulated manually or electrically. Thus, acupuncture stimulates the somatic afferent nerves of the skin and muscles. The somatic sensory information from the body is carried to the cortex area of the brain. Somatic sensory fibers also project to the various nuclei, including the brain stem, periaqueductal gray (PAG), and paraventricular nucleus (PVN) of the hypothalamus. Somatosensory pathways stimulated by acupuncture activate these nuclei. Activation of the brain stem modulates the imbalance between sympathetic activity and parasympathetic activity. Opioid released from the PAG is involved in mediating antiemetic and antinociceptive effects of acupuncture. Oxytocin release from the PVN mediates antistress and antinociceptive effects of acupuncture. Acupuncture may be effective in patients with functional gastrointestinal (GI) disorders because of its effects on GI motility and visceral pain. It is expected that acupuncture is used in the treatment of patients with functional GI disorders.

Agents that act luminally to treat diarrhoea and constipation

Diarrhoea and constipation are common clinical complaints that negatively affect quality of life, reduce work productivity and lead to considerable health-care expenditure. A variety of therapies have been used to treat these conditions. Unlike drugs that require systemic absorption to exert their effects, luminally acting agents improve diarrhoea and constipation by altering intestinal and/or colonic motility, as well as mucosal absorption and secretion, through a variety of mechanisms. Examples of luminally acting agents for diarrhoea include peripherally acting opiate analogues, enkephalinase inhibitors, bile-acid binding agents, nonabsorbed antibiotics, probiotics, bismuth-containing compounds, berberine and agents with possible effects on intestinal secretion or permeability. Luminally acting drugs for constipation include bulking agents, surfactants, osmotics, stimulants, chloride-channel activators, probiotics, drugs that increase delivery of bile acids to the colon and natural therapies such as prunes and hemp seed extract. As the physiological effects of luminally acting drugs are largely confined to the gastrointestinal tract, these agents are unlikely to cause adverse effects outside of the gastrointestinal tract.

Effects of Hange-shashin-to (TJ-14) and Keishi-ka-shakuyaku-to (TJ-60) on contractile activity of circular smooth muscle of the rat distal colon

The Japanese Kampo medicines Hange-shashin-to (TJ-14) and Keishi-ka-shakuyaku-to (TJ-60) have been used to treat symptoms of human diarrhea on an empirical basis as Japanese traditional medicines. However, it remains unclear how these drugs affect smooth muscle tissues in the distal colon. The aim of the present study was to investigate the effects of TJ-14 and TJ-60 on the contractile activity of circular smooth muscle from the rat distal colon. TJ-14 and TJ-60 (both 1 mg/ml) inhibited spontaneous contractions of circumferentially cut preparations with the mucosa intact. Blockade of nitric oxide (NO) synthase or soluble guanylate cyclase activity abolished the inhibitory effects of TJ-60 but only attenuated the inhibitory effects of TJ-14. Apamin (1 μM), a blocker of small-conductance Ca(2+)-activated K(+) channels (SK channels), attenuated the inhibitory effects of 5 mg/ml TJ-60 but not those of 5 mg/ml TJ-14. TJ-14 suppressed contractile responses (phasic contractions and off-contractions) evoked by transmural nerve stimulation and increased basal tone, whereas TJ-60 had little effect on these parameters. These results suggest that 1 mg/ml TJ-14 or TJ-60 likely inhibits spontaneous contractions of the rat distal colon through the production of NO. Activation of SK channels seems to be involved in the inhibitory effects of 5 mg/ml TJ-60. Since TJ-14 has potent inhibitory effects on myogenic and neurogenic contractile activity, TJ-14 may be useful in suppressing gastrointestinal motility.

Probiotics use to treat irritable bowel syndrome

INTRODUCTION

Irritable bowel syndrome (IBS) is a common chronic gastrointestinal (GI) tract disorder with significant disability and a considerable financial burden to health service due to the consumption of resources including investigations, physician time, and cost of treatment. Despite availability of multiple treatment options, there is still poor functional recovery.

AREAS COVERED

Probiotics has been investigated as a promising treatment for IBS, and have demonstrated beneficial effects in some patients. There are many clinical trials investigating the therapeutic benefits of probiotics in IBS but most of them are heterogenic in terms of dose or species used and clinical endpoints. However, recent major meta-analyses revealed benefits of probiotics in patients with IBS. Inhibition of binding of pathogenic bacteria to intestinal epithelial cells, enhancing barrier function of intestinal epithelial, acidification of the colon, suppression of the growth of pathogens, modulation of immunity, inhibition of visceral hypersensitivity, alteration in mucosal response to stress, and improvement of bowel dysmotility are among mechanisms that probiotics may act. Most commonly used probiotics come from the genera Bifidobacterium and Lactobacillus but other species are in trial.

EXPERT OPINION

Although further studies are still needed, current evidences are almost enough to convince experts that probiotics are efficient in the treatment of IBS.