Functional Gastrointestinal Disorders: Complex Treatments for Complex Pathophysiological Mechanisms

Effects of Cirsium palustre Extracts and Their Main Flavonoids on Colon Motility-An Ex Vivo Study

For centuries, various species from the genus Cirsium have been utilized in traditional medicine worldwide. A number of ethnopharmacological reports have pointed out that Cirsium plants can be applied to diminish digestive problems. Among them, Cirsium palustre (L.) Scop. (Asteraceae) stands out as a promising herbal drug candidate because its constituents exhibit antimicrobial and antioxidant potential, as evidenced by ethnopharmacological reports. As a result, the species is particularly intriguing as an adjunctive therapy for functional gastrointestinal and motility disorders. Our research goal was to verify how the extracts, fractions, and main flavonoids of C. palustre affect colon contractility under ex vivo conditions. An alternative model with porcine-isolated colon specimens was used to identify the effects of C. palustre preparations and their primary flavonoids. LC-ESI-MS was utilized to evaluate the impacts of methanol (CP1), methanolic 50% (CP2), and aqueous (CP3) extracts as well as diethyl ether (CP4), ethyl acetate (CP5), and n-butanol (CP6) fractions. Additionally, the impacts of four flavonoids, apigenin (API), luteolin (LUT), apigenin 7-O-glucuronide (A7GLC), and chrysoeriol (CHRY), on spontaneous and acetylcholine-induced motility were assessed under isometric conditions. The results showed that C. palustre extracts, fractions, and their flavonoids exhibit potent motility-regulating effects on colonic smooth muscle. The motility-regulating effect was observed on spontaneous and acetylcholine-induced contractility. All extracts and fractions exhibited an enhancement of the spontaneous contractility of colonic smooth muscle. For acetylcholine-induced activity, CP1, CP2, and CP4 caused a spasmolytic effect, and CP5 and CP6 had a spasmodic effect. LUT and CHRY showed a spasmolytic effect in the case of spontaneous and acetylcholine-induced activity. In contrast, API and A7GLC showed a contractile effect in the case of spontaneous and pharmacologically induced activity. Considering the results obtained from the study, C. palustre could potentially provide benefits in the treatment of functional gastrointestinal disorders characterized by hypomotility and hypermotility.

Emotional-Single Prolonged Stress: A promising model to illustrate the gut-brain interaction

Excessive stress can precipitate depression and anxiety diseases, and damage gastrointestinal functionality and microbiota changes, favoring the development of functional gastrointestinal disorders (FGIDs) - defined by dysregulation in the brain-gut interaction. Therefore, the present study investigated if Emotional-Single Prolonged Stress (E-SPS) induces depressive/anxiety-like phenotype and gut dysfunction in adult Swiss male mice. For this, mice of the E-SPS group were subjected to three stressors sequential exposure: immobilization, swimming, and odor of the predator for 7 days (incubation period). Next, animals performed behavior tests and 24 h later, samples of feces, blood, and colon tissue were collected. E-SPS increased the plasma corticosterone levels, immobility time in the tail suspension and forced swim test, decreased the grooming time in the splash test, OAT%, and OAE% in the elevated plus-maze test, as well as increased anxiety index. Mice of E-SPS had increased % of intestinal transit rate, % of fecal moisture content, and fecal pellets number, and decreased Claudin1 content in the colon. E-SPS decreased the relative abundance of Bacteroidetes phylum, Bacteroidia class, Bacteroidales order, Muribaculaceae and Porphyromonadaceae family, Muribaculum, and Duncaniella genus. However, E-SPS increased Firmicutes and Actinobacteria phylum, Coriobacteriales order, and the ratio of Firmicutes/Bacteroidetes, and demonstrated Mucispirillum genus presence. The present study showed that E-SPS induced depressive/anxiety-like phenotype, predominant diarrhea gut dysfunction, and modulated the gut bacterial microbiota profile in male adult Swiss mice. E-SPS might be a promising model for future studies on the brain-gut interaction and the development of FGIDs with psychological comorbidities.

Incongruent Views of Functioning between Patients and Gastroenterologists: A Mixed Methods Study

Gastrointestinal patients, especially those diagnosed with functional digestive disorders (FGIDs), usually present a complex clinical picture that poses a challenge for their management in primary care. The main objective of the current research was to examine the relationship of the congruence of the perception of severity and quality of life between gastroenterologists and their patients with psychological distress and the helping attitude experienced by the latter attended in primary care centres. Additionally, we wanted to explore patients' and practitioners' perceptions. We performed a cross-sectional study with a total of 2261 patients (1562 analysed) that attended three primary care centres. Patients completed questionnaires that measured physical functioning, distress, and perception of helping attitude. Gastroenterologists registered the functional status of each participating patient. Patients were then invited to take part in the qualitative part of the study if they were considered to have incongruent views on their functioning with their gastroenterologist. In total, 52 patients took part in one of eight focus groups. Additionally, four individual interviews were carried out with three gastroenterologists and one consultation-liaison psychiatrist specialised in FGIDs. Both incongruence and functional diagnosis correlated with distress. However, incongruent views between patients and gastroenterologists explained more variance. Statistically significant differences in patients' helping attitude perception were detected between diagnostic but no incongruence groups. In the second stage of the study, a total of five themes were identified from the patient focus groups and the gastroenterologist interviews: illness-emotional and personal problems, disease-health system interaction, health system, intervention, and patients. The current research allowed us to confirm that incongruence in the perception of severity and quality of life between gastroenterologists and patients is related to psychological distress and that this occurs in a multifactorial context where the characteristics of the disorder interact with those of the health system.

Tissue engineering of the gastrointestinal tract: the historic path to translation

The gastrointestinal (GI) tract is imperative for multiple functions including digestion, nutrient absorption, and timely waste disposal. The central feature of the gut is peristalsis, intestinal motility, which facilitates all of its functions. Disruptions in GI motility lead to sub-optimal GI function, resulting in a lower quality of life in many functional GI disorders. Over the last two decades, tissue engineering research directed towards the intestine has progressed rapidly due to advances in cell and stem-cell biology, integrative physiology, bioengineering and biomaterials. Newer biomedical tools (including optical tools, machine learning, and nuanced regenerative engineering approaches) have expanded our understanding of the complex cellular communication within the GI tract that lead to its orchestrated physiological function. Bioengineering therefore can be utilized towards several translational aspects: (i) regenerative medicine to remedy/restore GI physiological function; (ii) in vitro model building to mimic the complex physiology for drug and pharmacology testing; (iii) tool development to continue to unravel multi-cell communication networks to integrate cell and organ-level physiology. Despite the significant strides made historically in GI tissue engineering, fundamental challenges remain including the quest for identifying autologous human cell sources, enhanced scaffolding biomaterials to increase biocompatibility while matching viscoelastic properties of the underlying tissue, and overall biomanufacturing. This review provides historic perspectives for how bioengineering has advanced over time, highlights newer advances in bioengineering strategies, and provides a realistic perspective on the path to translation.

COVID-19 Outbreak and its Burden on a New Wave of Functional Gastrointestinal Disorders

The current outbreak of COVID-19 infection among humans is strongly impacting global physical and mental health. This outbreak can induce or exacerbate some chronic disorders such as functional gastrointestinal disorders (FGIDs) due to stress, anxiety, depression, insomnia, denial, anger, and fear. The current focus on the physical aspects of COVID-19 infection may distract public attention from the psychosocial consequences of this outbreak. The mental disorders related to this outbreak may develop and extend FGIDs in the long term. FGIDs have a significant impact on daily activities and quality of life and also cause high economic burdens through direct medical costs and loss of productivity. The purpose of this mini-review was to emphasize the critical state of old and new cases of FGIDs during the COVID-19 outbreak. Published English papers about mental health disorders related to the COVID19 outbreak or before the infectious outbreak, stress, and FGIDs were considered and reviewed. We selected articles which were current and had the most relevance to FGIDs, psycho-somatization, and infectious outbreak.

Physiological mechanisms of unexplained (functional) gastrointestinal disorders

Functional gastrointestinal disorders (FGIDs) encompass a range of complex conditions with similar clinical characteristics and no overt pathology. Recent recognition of sub-clinical pathologies in FGIDs, in conjunction with physiological and biochemical abnormalities including increased intestinal permeability, microbial profile alterations, differences in metabolites and extra-intestinal manifestations of disease, call into question the designation of these conditions as 'functional'. This is despite significant heterogeneity in both symptom profile and specifics of reported physiological abnormalities hampering efforts to determine defined mechanisms that drive onset and chronicity of symptoms. Instead, the literature demonstrates these conditions are disorders of homeostatic imbalance, with disruptions in both host and microbial function and metabolism. This imbalance is also associated with extraintestinal abnormalities including psychological comorbidities and fatigue that may be a consequence of gastrointestinal disruption. Given the exploitation of such abnormalities will be crucial for improved therapeutic selection, an enhanced understanding of the relationship between alterations in function of the gastrointestinal tract and the response of the immune system is of interest in identifying mechanisms that drive FGID onset and chronicity. Considerations for future research should include the role of sex hormones in regulating physiological functions and treatment responses in patients, as well as the importance of high-level phenotyping of clinical, immune, microbial and physiological parameters in study cohorts. There is opportunity to examine the functional contribution of the microbiota and associated metabolites as a source of mechanistic insight and targets for therapeutic modulation.

Influence of Tilia tomentosa Moench Extract on Mouse Small Intestine Neuromuscular Contractility

Functional gastrointestinal disorders (FGIDs) are characterized by abdominal pain, bloating and bowel disturbances. FGID therapy is primarily symptomatic, including treatment with herbal remedies. Flower extract of Tilia tomentosa Moench (TtM) is occasionally used as an anti-spasmodic in popular medicine. Since its effect on intestinal response is unknown, we evaluated the influence of TtM extract on small intestine contractility. Ileal preparations from C57BL/6J mice were mounted in organ baths to assess changes in muscle tension, following addition of TtM extract (0.5–36 μg/mL) or a vehicle (ethanol). Changes in contractile response to receptor- and non-receptor-mediated stimuli were assessed in ileal preparations pretreated with 12 μg/mL TtM. Alterations in the enteric nervous system neuroglial network were analyzed by confocal immunofluorescence. Increasing addition of TtM induced a marked relaxation in ileal specimens compared to the vehicle. Pretreatment with TtM affected cholinergic and tachykininergic neuromuscular contractions as well as K⁺-induced smooth muscle depolarization. Following incubation with TtM, a significant reduction in non-adrenergic non-cholinergic-mediated relaxation sensitive to Nω-Nitro-L-arginine methyl ester hydrochloride (pan-nitric oxide synthase inhibitor) was found. In vitro incubation of intestinal specimens with TtM did not affect the myenteric plexus neuroglial network. Our findings show that TtM-induced intestinal relaxation is mediated by nitric oxide pathways, providing a pharmacological basis for the use of TtM in FGIDs.

Draft Genome Sequence of Streptococcus salivarius AGIRA0003, Isolated from Functional Gastrointestinal Disorder Duodenal Tissue

Patients suffering functional dyspepsia symptoms have been shown to possess a greater relative abundance of Streptococcus compared to asymptomatic controls. Here, we describe the isolation and genomic features of a new Streptococcus isolate, from the duodenal tissue of a subject reporting dyspeptic symptoms, taxonomically assigned to Streptococcus salivarius and designated strain AGIRA0003.

Pharmacological effects of Pugionium cornutum (L.) Gaertn. extracts on gastrointestinal motility are partially mediated by quercetin

BACKGROUND

The majority of global population suffer from various functional gastrointestinal disorders. Pugionium cornutum (L.) Gaertn. (PCG) is used to relieve indigestive symptoms in traditional Chinese medicine. However, little is known about the effects of bioactive components from PCG extracts on gastrointestinal motility.

METHODS

Crude ethanol extract of PCG (EEP) was prepared from Pugionium cornutum (L.) Gaertn. Different solvents were used to prepare fine extracts from EEP, including water extract of PCG (WEP), petroleum ether extract of PCG (PEEP), dichloromethane extract of PCG (DEP) and ethyl acetate extract of PCG (EAEP). Smooth muscle cell model and colonic smooth muscle stripe model were used to test the bioactive effects and mechanisms of different PCG extracts on contraction and relaxation. Diverse chromatographic methods were used to identify bioactive substances from PCG extracts.

RESULTS

EEP was found to promote the relaxation of gastric smooth muscle cell and inhibit the contraction of colonic smooth muscle strip. Among the fractions of EEP, EAEP mainly mediated the relaxation effect by stimulating intracellular calcium influx. Further evidences revealed that EAEP was antagonistic to acetylcholine. In addition, COX and NO-GC-PKC pathways may be also involved in EAEP-mediated relaxation effect. Quercetin was identified as a bioactive compound from PCG extract for the relaxation effect.

CONCLUSION

Our research supports the notion that PCG extracts promote relaxation and inhibits contraction of gastrointestinal smooth muscle at least partially through the effect from quercetin.

The enteric nervous system in gastrointestinal disease etiology

A highly conserved but convoluted network of neurons and glial cells, the enteric nervous system (ENS), is positioned along the wall of the gut to coordinate digestive processes and gastrointestinal homeostasis. Because ENS components are in charge of the autonomous regulation of gut function, it is inevitable that their dysfunction is central to the pathophysiology and symptom generation of gastrointestinal disease. While for neurodevelopmental disorders such as Hirschsprung, ENS pathogenesis appears to be clear-cut, the role for impaired ENS activity in the etiology of other gastrointestinal disorders is less established and is often deemed secondary to other insults like intestinal inflammation. However, mounting experimental evidence in recent years indicates that gastrointestinal homeostasis hinges on multifaceted connections between the ENS, and other cellular networks such as the intestinal epithelium, the immune system, and the intestinal microbiome. Derangement of these interactions could underlie gastrointestinal disease onset and elicit variable degrees of abnormal gut function, pinpointing, perhaps unexpectedly, the ENS as a diligent participant in idiopathic but also in inflammatory and cancerous diseases of the gut. In this review, we discuss the latest evidence on the role of the ENS in the pathogenesis of enteric neuropathies, disorders of gut-brain interaction, inflammatory bowel diseases, and colorectal cancer.

U.S. FDA Approved Drugs from 2015-June 2020: A Perspective

In the present work, we report compilation and analysis of 245 drugs, including small and macromolecules approved by the U.S. FDA from 2015 until June 2020. Nearly 29% of the drugs were approved for the treatment of various types of cancers. Other major therapeutic areas of focus were infectious diseases (14%); neurological conditions (12%); and genetic, metabolic, and cardiovascular disorders (7-8% each). Itemization of the approved drugs according to the year of approval, sponsor, target, chemical class, major drug-metabolizing enzyme(s), route of administration/elimination, and drug-drug interaction liability (perpetrator or/and victim) is presented and discussed. An effort has been made to analyze the pharmacophores to identify the structural (e.g., aromatic, heterocycle, and aliphatic), elemental (e.g., boron, sulfur, fluorine, phosphorus, and deuterium), and functional group (e.g., nitro drugs) diversity among the approved drugs. Further, descriptor-based chemical space analysis of FDA approved drugs and several strategies utilized for optimizing metabolism leading to their discoveries have been emphasized. Finally, an analysis of drug-likeness for the approved drugs is presented.

Importance of Non-pharmacological Approaches for Treating Irritable Bowel Syndrome: Mechanisms and Clinical Relevance

Chronic visceral pain represents a major unmet clinical need with the severity of pain ranging from mild to so severe as to prevent individuals from participating in day-to-day activities and detrimentally affecting their quality of life. Although chronic visceral pain can be multifactorial with many different biological and psychological systems contributing to the onset and severity of symptoms, one of the major triggers for visceral pain is the exposure to emotional and physical stress. Chronic visceral pain that is worsened by stress is a hallmark feature of functional gastrointestinal disorders such as irritable bowel syndrome (IBS). Current pharmacological interventions for patients with chronic visceral pain generally lack efficacy and many are fraught with unwanted side effects. Cognitive behavioral therapy (CBT) has emerged as a psychotherapy that shows efficacy at ameliorating stress-induced chronic visceral pain; however, the molecular mechanisms underlying CBT remain incompletely understood. Preclinical studies in experimental models of stress-induced visceral pain employing environmental enrichment (EE) as an animal model surrogate for CBT are unraveling the mechanism by which environmental signals can lead to long-lasting changes in gene expression and behavior. Evidence suggests that EE signaling interacts with stress and nociceptive signaling. This review will (1) critically evaluate the behavioral and molecular changes that lead to chronic pain in IBS, (2) summarize the pharmacological and non-pharmacological approaches used to treat IBS patients, and (3) provide experimental evidence supporting the potential mechanisms by which CBT ameliorates stress-induced visceral pain.

Epidemiologic Burden and Treatment of Chronic Symptomatic Functional Bowel Disorders in the United States: A Nationwide Analysis

BACKGROUND & AIMS

Functional bowel disorders (FBDs) are the most common gastrointestinal problems managed by physicians. We aimed to assess the burden of chronic symptomatic FBDs on ambulatory care delivery in the United States and evaluate patterns of treatment.

METHODS

Data from the National Ambulatory Medical Care Survey were used to estimate annual rates and associated costs of ambulatory visits for symptomatic irritable bowel syndrome, chronic functional abdominal pain, constipation, or diarrhea. The weighted proportion of visits associated with pharmacologic and nonpharmacologic (stress/mental health, exercise, diet counseling) interventions were calculated, and predictors of treatment strategy were evaluated in multivariable multinomial logistic regression.

RESULTS

From 2007-2015, approximately 36.9 million (95% CI, 31.4-42.4) weighted visits in patients of non-federally employed physicians for chronic symptomatic FBDs were sampled. There was an annual weighted average of 2.7 million (95% CI, 2.3-3.2) visits for symptomatic irritable bowel syndrome/chronic abdominal pain, 1.0 million (95% CI, 0.8-1.2) visits for chronic constipation, and 0.7 million (95% CI, 0.5-0.8) visits for chronic diarrhea. Pharmacologic therapies were prescribed in 49.7% (95% CI, 44.7-54.8) of visits compared to nonpharmacologic interventions in 19.8% (95% CI, 16.0-24.2) of visits (P < .001). Combination treatment strategies were more likely to be implemented by primary care physicians and in patients with depression or obesity. The direct annual cost of ambulatory clinic visits alone for chronic symptomatic FBDs is approximately US$358 million (95% CI, 233-482 million).

CONCLUSIONS

The management of chronic symptomatic FBDs is associated with considerable health care resource use and cost. There may be an opportunity to improve comprehensive FBD management because fewer than 1 in 5 ambulatory visits include nonpharmacologic treatment strategies.

Evaluation of the effects of Bidens tripartita extracts and their main constituents on intestinal motility - An ex vivo study

ETHNOPHARMACOLOGICAL RELEVANCE

Based on traditional medicine, infusions of Bidens species (Asteraceae) have been successfully used in the treatment of acute and chronic enteritis. Additionally, ethnopharmacological reports demonstrating the gastrointestinal, gastroprotective, anti-inflammatory, antiulcerogenic and immunomodulatory potency of Bidens tripartita Linn. (Asteraceae) and its constituents make the plant a particularly interesting herbal drug candidate for the supportive treatment of functional gastrointestinal and motility disorders.

AIM OF THE STUDY

The study aimed to verify the effects of B. tripartita and its main flavonoid constituents on intestinal contractility patterns under ex vivo conditions.

MATERIALS AND METHODS

The effects of B. tripartita preparations and their main flavonoids were identified using an alternative model of porcine isolated jejunum specimens. Using LC-ESI-MS, the effects of six different standardized extracts, aqueous (BT1), methanolic 50% (BT2), methanolic (BT3), diethyl ether (BT4), ethyl acetate (BT5) and butanol (BT6) (0.001-0.1 mg/mL), as well as three pure isolated flavonoids, luteolin (LUT), cynaroside (CYN) and flavanomarein (ION) (0.001-100 μM), were evaluated towards spontaneous and acetylcholine-induced motility.

RESULTS AND CONCLUSION

s: The results showed the potent prokinetic effects of the B. tripartita extracts and their flavonoids on jejunum smooth muscle. The myocontractile effect was observed on both spontaneous and acetylcholine-induced contractility. There were no substantial differences in the magnitude of myocontractile effects between all six extracts with the exception of the butanol extract which seemed to have a slightly stronger prokinetic effect than the other extracts. The use of extracts at the highest tested concentrations provoked an approximately 1.5-fold increased reaction to acetylcholine compared to the control treatment. The myocontractile effect of the single flavonoids justifies the hypothesis that these secondary metabolites are responsible for the prokinetic activity of all the tested extracts. Among the tested flavonoids, CYN appeared to be the most potent ingredient of B. tripartita; the increase in the response to acetylcholine in the presence of this compound exceeded 250% of the control reaction. In view of the obtained results, the range of functional gastrointestinal disorders in which B. tripartita could be expected to bring benefits include the predominantly constipative phases of irritable bowel syndrome and dyspeptic complaints in which treatment protocols usually involve gastroprokinetics.

Reflux Hypersensitivity: How to Approach Diagnosis and Management

PURPOSE OF REVIEW

This paper aims to review the definition and diagnostic criteria for reflux hypersensitivity and comment on the present and future management of this condition.

RECENT FINDINGS

In 2016, the Rome IV criteria redefined reflux hypersensitivity as characterized by typical reflux symptoms, absence of endoscopic mucosal disease, absence of pathologic gastroesophageal reflux, and positive symptom correlation between reflux and heartburn episodes. Though uncertain, TPRV1 receptors have been implicated in the pathophysiology of reflux hypersensitivity. Recent studies have shown neuromodulators like SSRIs, SNRIs, and TCAs may be the future of managing this condition. With the release of the Rome IV criteria and availability of continuous pH monitoring, the diagnosis of reflux hypersensitivity has become more streamlined. Though there is no definitive therapy for reflux hypersensitivity, several anti-secretory agents and neuromodulators have shown some efficacy in therapeutic trials. The lack of large-scale, randomized controlled trials, however, reinforces the need for further research into the pharmacotherapy of reflux hypersensitivity.

Functional gastrointestinal disorders in women with systemic lupus erythematosus: A case-control study

BACKGROUND

Systemic lupus erythematosus (SLE) is an autoimmune disease with multisystemic involvement. Gastrointestinal (GI) manifestations are frequent but functional gastrointestinal disorders (FGIDs) have scarcely been studied in SLE. To determine the prevalence of FGIDs and their potential risk factors in SLE female patients vs controls.

METHODS

Systemic lupus erythematosus patients meeting the American College of Rheumatology (ACR) criteria and controls completed the Rome III questionnaire for FGIDs and a structured interview to assess sociodemographic, clinical, and treatment variables after excluding organic GI diseases. Logistic regression was used to determine risk factors (ie, alcohol drinking, medications) for FGIDs.

KEY RESULTS

Responders included 113 SLE patients and 122 age-matched controls. The presence of at least one FGIDs was higher in SLE (73.4%) vs controls (54.1%), P = .003. The most frequent FGIDs in SLE patients were nausea and vomiting disorders (NVD), belching disorders, globus, anorectal pain, functional heartburn (FH), and functional bloating (FB). After adjustment for confounding variables, SLE was associated with NVD (OR: 7.1, 95% CI: 2.7-19.1) globus (3.5, 1.3-9.3), anorectal pain (3.4, 1.4-8.4), and FH (2.5, 1.5-4.4). The simultaneous presence of >1 FGID was more common in SLE patients than controls (69.8% vs 31.8%). Glucocorticoids (5.2, 1.3-19.9) and non-steroidal anti-inflammatory drugs (NSAIDs; 3.0, 1.1-8.0) were associated with any FGID in SLE patients while alcohol drinking with gallbladder/sphincter of Oddi disorders 7.4 (1.1-47.3).

CONCLUSIONS AND INFERENCES

Functional gastrointestinal disorders are more frequent in SLE patients compared with controls. Medication that may alter gastrointestinal homeostasis, such as glucocorticoids and NSAIDs, are potential risk factors for FGIDs in SLE.