The use of medicinal cannabis has a long history dating back thousands of years. Recent discoveries have shed light on its mechanism of action with the identification of cannabinoid receptors and endocannabinoids, which make up the body\'s endocannabinoid system. Cannabinoid receptors, particularly the cannabinoid 1 and 2 receptors, play a crucial role in modulating the gut-brain axis and serve as potential therapeutic targets for gastrointestinal motility and inflammatory disorders. With increasing legalization of cannabis and a rising number of users, understanding the effects of cannabis on gut motility is essential for nuclear medicine providers. Although tetrahydrocannabinol, the principal psychoactive constituent of cannabis, may decrease gut motility in experimental settings, it appears to paradoxically improve symptoms in gastroparesis. Treatment effects are difficult to measure given the large number of variables that could significantly alter outcomes, such as cannabinoid type, potency, and route of intake. Another consideration is the highly personalized gut microbiome, which directly interacts with the endocannabinoid system. Further research is required to delineate these multifaceted, complex cannabinoid interactions. The goal of this article is to explore the knowns and unknowns of the impact of cannabis on the alimentary system.

This review focuses on the role of magnetic resonance imaging (MRI) in the evaluation of the gastrointestinal tract (GI MRI), analyzing the major technical advances achieved in this field, such as diffusion-weighted imaging, molecular imaging, motility studies, and artificial intelligence. Today, MRI performed with the more advanced imaging techniques allows accurate assessment of many bowel diseases, particularly inflammatory bowel disease and rectal cancer; in most of these diseases, MRI is invaluable for diagnosis, staging, and disease monitoring under treatment. Several MRI parameters are currently considered activity biomarkers for inflammation and neoplastic disease. Furthermore, in younger patients with acute or chronic GI disease, MRI can be safely used for short-term follow-up studies in many critical clinical situations because it is radiation-free. MRI assessment of functional gastro-esophageal and small bowel disorders is still in its infancy but very promising, while it is well established and widely used for dynamic assessment of anorectal and pelvic floor dysfunction; MRI motility biomarkers have also been described. There are still some limitations to GI MRI related to high cost and limited accessibility. However, technical advances are expected, such as faster sequences, more specific intestinal contrast agents, AI analysis of MRI data, and possibly increased accessibility to GI MRI studies. Clinical interest in the evaluation of bowel disease using MRI is already very high, but is expected to increase significantly in the coming years.

Neuronal nitric oxide synthase (nNOS) has various roles as a neurotransmitter. However, studies to date have produced insufficient data to fully support the correlation between nNOS and bowel motility. This study aimed to investigate the correlation between nNOS expression and gastrointestinal (GI) tract motility using a stress-induced neonatal maternal separation (NMS) mouse model. In this study, we generated a genetically modified mouse with the HiBiT sequence knock-in into the nNOS gene using CRISPR/Cas9 for analyzing accurate nNOS expression. nNOS expression was measured in the stomach, small intestine, large intestine, adrenal gland, and hypothalamus tissues after establishing the NMS model. The NMS model exhibited a significant increase in nNOS expression in large intestine, adrenal gland, and hypothalamus. Moreover, a significant positive correlation was observed between whole gastrointestinal transit time and the expression level of nNOS. We reasoned that NMS induced chronic stress and consequent nNOS activation in the hypothalamic-pituitary-adrenal (HPA) axis, and led to an excessive increase in intestinal motility in the lower GI tract. These results demonstrated that HiBiT is a sensitive and valuable tool for analyzing in vivo gene activation, and nNOS could be a biomarker of the HPA axis-linked lower intestinal tract dysfunction.

BACKGROUND: Despite constipation being a common clinical condition in older adults, the clinical relevance of constipation related to frailty is less studied. Hence, we aimed to investigate the association between chronic constipation (CC) and frailty in older adults.
METHODS: This is a cross-sectional analysis of a population-based, prospective cohort study of 1278 community-dwelling older adults in South Korea. We used the Rome criteria to identify patients with irritable bowel syndrome with predominant constipation (IBS-C) and functional constipation (FC). We investigated whether participants consistent with the criteria for IBS-C and FC had CC. Frailty was assessed using the Cardiovascular Health Study (CHS) frailty phenotype.
RESULTS: In the study population with a mean age of 75.3 ± 6.3 years, 136 (10.7%) had CC. The participants with CC were older, had higher medication burdens, and had worse physical performances compared to those without CC (All P < .05). By association analysis, the prevalence of CC was associated with frailty by the CHS criteria (P < .001). The CHS frailty score was associated with the presence of CC by the univariate logistic regression analysis and the multivariate analysis adjusted for age, sex, and multimorbidity.
CONCLUSIONS: Frailty was associated with CC in community-dwelling older people, suggesting that constipation should be considered as an important geriatric syndrome in clinical practice concerning frail older adults.

Hirschsprung\'s disease (HSCR) is a common congenital defect. It occurs when bowel colonization by neural crest-derived enteric nervous system (ENS) precursors is incomplete during the first trimester of pregnancy. Several sources of candidate cells have been previously studied for their capacity to regenerate the ENS, including enteric neural crest stem cells (En-NCSCs) derived from native intestine or those simulated from human pluripotent stem cells (hPSCs). However, it is not yet known whether the native NCSCs other than En-NCSCs would have the potential of regenerating functional enteric neurons and producing neuron dependent motility under the intestinal environment. The present study was designed to determine whether premigratory NCSCs (pNCSCs), as a type of the nonenteric NCSCs, could form enteric neurons and mediate the motility. pNCSCs were firstly transplanted into the colon of adult mice, and were found to survive, migrate, differentiate into enteric neurons, and successfully integrate into the adult mouse colon. When the mixture of pNCSCs and human intestinal organoids was implanted into the subrenal capsule of nude mice and grown into the mature tissue-engineered intestine (TEI), the pNCSCs-derived neurons mediated neuron-dependent peristalsis of TEI. These results show that the pNCSCs that were previously assumed to not be induced by intestinal environment or cues can innervate the intestine and establish neuron-dependent motility. Future cell candidates for ENS regeneration may include nonenteric NCSCs.

We aimed to investigate the effects of chewing gum on bowel activity and postoperative pain in patients undergoing laparoscopic hysterectomy. Patients were randomised into two groups (n = 58, study; n = 51, control). In the study group, patients started chewing sugarless gum every 2 h for 15 min, beginning at the second postoperative hour. The control group did not chew gum, and they received standard postoperative care. Both groups were compared primarily in terms of the amount of time until the first bowel movement, the time of the first passage of flatus and the time of first defaecation. The amount of time until the first bowel movement, the time of the first passage of flatus and the time of the first defaecation were found to be significantly shorter in the chewing gum group (p < .001). The amount of postoperative analgesics that were needed and VAS scores at 6-hours and 24-hours postoperatively, were found to be lower in the study group than in the control group (p < .001). Chewing gum was found to have beneficial effects on bowel motility and postoperative pain in patients undergoing laparoscopic hysterectomy. This affordable and simple method could be recommended to patients after total laparoscopic hysterectomy.Impact statementWhat is already known on this subject? Postoperative gastrointestinal dysfunction remains a source of morbidity and the major determinant of length of stay after abdominal operation. The mechanism of enhanced recovery from postoperative gastrointestinal dysfunction with the help of chewing gum is believed to be the cephalic-vagal stimulation of digestion which increases the promotability of neural and humoral factors that act on different parts of the gastrointestinal tract.What do the results of this study add? The findings of previous randomised controlled studies have been inconsistent regarding the effect of chewing gum on postoperative bowel function following abdominal gynecological surgery. In this randomised prospective study, we found that chewing gum early in the postoperative period after total laparoscopic hysterectomy hastened time to bowel motility and flatus. To our knowledge this is the first study of the impact of chewing gum on bowel motility after total laparoscopic hysterectomy.What are the implications of these findings for clinical practice and/or further research? Chewing gum early in the postoperative period following laparoscopic hysterectomy hastens time to bowel motility and flatus. The use of chewing gum is a simple and cheap strategy for promoting the recovery of gastrointestinal functions.

At the most fundamental level, the bowel facilitates absorption of small molecules, regulates fluid and electrolyte flux, and eliminates waste. To successfully coordinate this complex array of functions, the bowel relies on the enteric nervous system (ENS), an intricate network of more than 500 million neurons and supporting glia that are organized into distinct layers or plexi within the bowel wall. Neuron and glial diversity, as well as neurotransmitter and receptor expression in the ENS, resembles that of the central nervous system. The most carefully studied ENS functions include control of bowel motility, epithelial secretion, and blood flow, but the ENS also interacts with enteroendocrine cells, influences epithelial proliferation and repair, modulates the intestinal immune system, and mediates extrinsic nerve input. Here, we review the many different cell types that communicate with the ENS, integrating data about ENS function into a broader view of human health and disease. In particular, we focus on exciting new literature highlighting relationships between the ENS and its lesser-known interacting partners.

Balneotherapy or spa therapy is usually known for different application forms of medicinal waters and its effects on the human body. Our purpose is to demonstrate the effect of balneotherapy on gastrointestinal motility. A total of 35 patients who were treated for osteoarthritis with balneotherapy from November 2013 through March 2015 at our hospital had a consultation at the general surgery for constipation and defecation disorders. Patients followed by constipation scores, short-form health survey (SF-12), and a colonic transit time (CTT) study before and after balneotherapy were included in this study, and the data of the patients were analyzed retrospectively. The constipation score, SF-12 score, and CTT were found statistically significant after balneotherapy (p < 0.05). The results of our study confirm the clinical finding that a 15-day course of balneotherapy with mineral water from a thermal spring (Bursa, Turkey) improves gastrointestinal motility and reduces laxative consumption in the management of constipation in middle-aged and elderly patients, and it is our belief that treatment with thermal mineral water could considerably improve the quality of life of these patients.

BACKGROUND: The aim of this study was to ascertain the impact of injury to the superior mesenteric nerve plexus caused by right colectomy with D3 extended mesenterectomy as performed in the prospective multicenter trial: \"Safe Radical D3 Right Hemicolectomy for Cancer through Preoperative Biphasic Multi-detector Computed Tomography\" in which all soft tissue surrounding the superior mesenteric vessels from the level of the middle colic artery to that of the ileocolic artery was removed.
METHODS: Bowel function and gastrointestinal quality of life in two consecutive cohorts that underwent right colectomy with and without D3 extended mesenterectomy were compared. Main outcome measures were the Diarrhea Assessment Scale (DAS) and Gastrointestinal Quality of Life Index (GIQLI). The data were collected prospectively through telephone interviews.
RESULTS: Forty-nine patients per group, comparable for age, sex, length of bowel resected but with significantly shorter follow-up time in the experimental group, were included. There was no difference in total DAS scores, subscores or additional questions except for higher bowel frequency scores in the D3 group (p = 0.02). Comparison of total GIQLI scores and subscales showed no difference between groups. Regression analysis with correction for confounding factors showed 0.48 lower bowel frequency scores in the D2 group (p = 0.022). Within the D3 group presence of jejunal arteries cranial to the D3 dissection area showed 1.78 lower DAS scores and 0.7 lower bowel frequency scores.
CONCLUSIONS: Small bowel denervation after right colectomy with D3 extended mesenterectomy leads to increased bowel frequency but does not impact gastrointestinal quality of life. Individual anatomical variants can affect postoperative bowel function differently despite standardized surgery.

OBJECTIVE: To evaluate continuously tagged 3 Tesla MRI for monitoring glucagon-induced bowel motility changes in healthy volunteers.
METHODS: After standardized oral bowel preparation, 10 healthy volunteers underwent a free-breathing, continuously tagged three-dimensional (3D) dynamic fast-field-echo (FFE), at a 3.36 Hz sampling frequency. One milligram of glucagon was administered intravenously during data acquisition. Each dataset was divided into four temporal sets of 2 min (period 1 to 4). Taglines were tracked automatically using a scale spaced based algorithm. Assessment of global spectral resolution was performed for three frequency intervals: 0.008-0.300 Hz (motility), 0.300-0.400 Hz (breathing motion), and 0.400-0.533 Hz (higher order motion). Additional analyses were performed at fine spectral resolution in frequency bands of 0.033 Hz. Glucagon-induced motility changes were investigated by means of a motility index (spectral power normalized to the maximal spectral power per-volunteer), resulting in a range of 0 to 1 (no motion to maximal motion). Statistical comparison was done for period 1 and 4 (Wilcoxon-signed rank test).
RESULTS: After glucagon administration, a significant decrease in the motility index was found for the low- (0.008-0.300 Hz) (P < 0.0001) and high-frequency interval (0.400-0.533 Hz) (P < 0.0001). Around breathing motion frequencies, no decrease in motility index was detected.
CONCLUSIONS: Free-breathing, continuously tagged MR imaging is a noninvasive method for automated bowel motility assessment and allows for detection of drug-induced changes.