Functional, Diagnostic and Therapeutic Aspects of Gastrointestinal Hormones

Effects of Phytosterols on Growth Performance, Serum Indexes, and Fecal Microbiota in Finishing Pigs

Phytosterols (PSs) are widely present in plants, particularly abundant in plant oils and seeds. PSs are reported to have various biological activities, such as lowering cholesterol, alongside antioxidant and antibacterial activities. This research examined the effects of PSs in finishing pigs, including growth performance, serum biochemistry, and fecal bacteria. Two treatment groups (each treatment group consisted of five biological replicates, and each replicate comprised five pigs housed communally) were randomly assigned to the fifty finishing pigs (equally divided by sex) of "Duroc × Landrace × Yorkshire" three-way cross with 79.76 ± 1.29 (kg) body weight. The control group (CON) was given basic food, while the experimental group was given basic food containing 300 mg PS/kg (PS). Dietary PS supplementation markedly raised the levels of average daily feed intake (ADFI) and apparent digestibility of dry matter (DM), crude protein (CP), ether extract (EE), and gross energy (GE) in comparison to the CON (p < 0.05). Additionally, PSs also significantly boosted the concentrations of high-density lipoprotein cholesterol (HDL-C), total protein (TP), catalase (CAT), superoxide dismutase (SOD), total antioxidant capacity (T-AOC), immunoglobulin G (IgG), motilin (MTL), and glucagon-like peptide-1 (GLP-1) (p < 0.05), and lowered the lactate dehydrogenase (LDH) level (p < 0.05). Both at the phyla and genus levels, the relative abundance of Firmicutes and Streptococcus increased significantly, and the relative abundance of Acinetobacter decreased significantly when adding phytosterols (p < 0.05). Overall, phytosterols dietary supplementation promotes immunity and antioxidant capacity in finishing pigs and boosts growth performance by improving nutrient digestibility.

The pyrethroid insecticide deltamethrin disrupts neuropeptide and monoamine signaling pathways in the gastrointestinal tract

Enteroendocrine cells (EECs) are a rare cell type of the intestinal epithelium. Various subtypes of EECs produce distinct repertoires of monoamines and neuropeptides which modulate intestinal motility and other physiologies. EECs also possess neuron-like properties, suggesting a potential vulnerability to ingested environmental neurotoxicants. One such group of toxicants are pyrethroids, a class of prevalent insecticides used residentially and agriculturally. Pyrethroids agonize voltage-gated sodium channels (VGSCs), inducing neuronal excitotoxicity, and affect the function of monoamine-producing neurons. Given their anatomical location at the interface with the environment and their expression of VGSCs, EECs likely represent a vulnerable cell-type to oral pyrethroid exposure. In this study, we used the EEC cell line, STC-1 cells, to evaluate the effects of the common pyrethroid deltamethrin on the functional status of EECs. We find that deltamethrin impacts both expression of serotonergic pathways and inhibits the adrenergic-evoked release of an EEC hormone, GLP-1, in vitro. In a mouse model of oral exposure, we found that deltamethrin induced an acute, yet transient, loss of intestinal motility, in both fed and fasted conditions. This constipation phenotype was accompanied by a significant decrease in peripheral serotonin production and an inhibition of nutrient-evoked intestinal hormone release. Together, these data demonstrate that deltamethrin alters monoaminergic signaling pathways in EECs and regulates intestinal motility. This work demonstrates a mechanistic link between pyrethroid exposure and intestinal impacts relevant to pyrethroid-associated diseases, including inflammatory bowel disease, neurodegenerative disease, and metabolic disorders.

Effects of natural products on functional constipation: analysis of active ingredient and mechanism

Constipation is a prevalent clinical ailment of the gastrointestinal system, yet its pathogenesis remains ambiguous. Despite the availability of numerous treatment modalities, they are insufficient in resolving the issue for patients. This work conducted a comprehensive review of the existing literature pertaining to the utilization of natural products for the treatment of constipation, with a focus on the efficacy of natural products in treating constipation, and to provide a comprehensive summary of their underlying mechanisms of action. Upon conducting a thorough review of the extant literature, we found that natural products can effectively treat constipation as modern synthetic drugs and compounded drugs with acetylcholinesterase (AChE) effects, rich in fiber and mucus, and the effects of increasing the tension of the ileum and gastrointestinal tract muscle, mediating signaling pathways, cytokine, excitability of the smooth muscle of the gastrointestinal tract, and regulating the homeostasis of intestinal flora. However, there is a wide variety of natural products, and there are still relatively few studies; the composition of natural products is complex, and the mechanism of action of natural products cannot be clarified. In the future, we need to further improve the detailed mechanism of natural products for the treatment of constipation.

Microbiota Implications in Endocrine-Related Diseases: From Development to Novel Therapeutic Approaches

This comprehensive review article delves into the critical role of the human microbiota in the development and management of endocrine-related diseases. We explore the complex interactions between the microbiota and the endocrine system, emphasizing the implications of microbiota dysbiosis for the onset and progression of various endocrine disorders. The review aims to synthesize current knowledge, highlighting recent advancements and the potential of novel therapeutic approaches targeting microbiota-endocrine interactions. Key topics include the impact of microbiota on hormone regulation, its role in endocrine pathologies, and the promising avenues of microbiota modulation through diet, probiotics, prebiotics, and fecal microbiota transplantation. We underscore the importance of this research in advancing personalized medicine, offering insights for more tailored and effective treatments for endocrine-related diseases.

Herbal medicine, Banxia-xiexin tang, for functional dyspepsia: a systematic review and meta-analysis

Background: The demand for complementary and alternative medicine for the management of functional dyspepsia (FD) is increasing due to the insufficient efficacy of conventional treatment options. In Asia, the Chinese herbal medicine formula Banxia-xiexin tang (BXT) has been used to treat FD. Methods: We searched 11 digital medical databases on 1 September 2021. Randomized controlled trials (RCTs) that investigated the efficacy of BXT or combination therapy (BXT plus Western medicines) for FD were selected. The outcome parameters were total clinical efficacy rate (TCE), motilin level, symptom checklist-90-revised (SCL-90-R), and visual analog scale (VAS) for dyspepsia and adverse events. Cochrane risk of bias tool 2.0 (RoB 2) was used for the quality assessment of included studies. Results: The meta-analysis comprised 57 RCTs with 5,525 participants. BXT was more efficacious, with a higher TCE than Western medicine. Combination therapy (BXT plus Western medicine) also resulted in a higher TCE than Western medicine. Combination therapy improved motilin levels and psychological symptoms to a greater extent than Western medicine, evidenced by a higher SCL-90-R score. However, no significant difference in VAS scores was observed between the BXT and placebo groups. BXT and combination therapy were associated with fewer adverse events than Western medicine or placebo. Conclusion: Our findings suggest that BXT and its combination therapy may be an effective and safe alternative treatment for FD. More RCTs with better methodologies are required to strengthen this evidence. Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42019123285], identifier [CRD42019123285].

Safety and effectiveness of traditional herbal medicine Siho-sogan-san in functional dyspepsia: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Functional dyspepsia (FD), a chronic upper gastrointestinal syndrome, seriously affects the quality of life of patients and poses a significant economic burden. Since the pathological mechanisms of FD have not been fully elucidated, conventional therapies such as prokinetics, proton pump inhibitors, and antidepressants have some limitations. Siho-sogan-san (SHS) is commonly used as a therapeutic alternative in traditional medicine; however, scientific and clinical evidence supporting its application in FD remains insufficient.

AIM OF THE STUDY

This review aimed to assess the safety and effectiveness of SHS and in combined with Western medicine (WM) for the treatment of FD.

METHODS

Eleven databases, including EMBASE, Medline, and Cochrane Library, were searched for randomized controlled trials (RCTs) on FD published before December 31, 2022. After two independent reveiwers sceened and selected studies according to the inclusion and exclusion criteria, clinical data was pooled and synthesized via Review Manager software. The outcome parameters included total clinical effectiveness rate (TCE), time for symptom improvement, levels of motilin and corticotropin-releasing hormone (CRH), and adverse events. Cochrane's risk of bias tool was used for quality assessment.

RESULTS

A total of 12 studies that included 867 participants comparing WM with SHS or combination therapy (SHS plus WM) were identified. Through a meta-analysis of five studies including 363 patients, SHS compared with WM showed a positive result in safely increasing TCE [risk ratio = 1.36, 95% confidence interval (CI) 1.22 to 1.51, P < 0.00001]. The time for symptom improvement, including abdominal pain, belching, nausea, vomiting, and abdominal distension, was significantly more shortened in the combination therapy than WM group. Furthermore, combination therapy resulted in greater secretion of motilin than WM alone [mean difference = 67.95, 95% CI 39.52 to 96.39, P < 0.00001]. No remarkable difference was observed in CRH levels between the combination therapy and WM groups. For a subgroup analysis, the administration of SHS based on the type of pattern identification (PI) showed larger effect size than in the group that do not consider PI.

CONCLUSIONS

These results suggest that SHS and combination therapy can be considered effective and safe options for the treatment of FD. However, owing to the low quality of the included studies, more well-designed investigational studies and RCTs with longer treatment and follow-up period are needed.

Gastrointestinal Hormones in Healthy Adults: Reliability of Repeated Assessments and Interrelations with Eating Habits and Physical Activity

Background: Gastrointestinal hormones (GIHs) are crucial for the regulation of a variety of physiological functions and have been linked to hunger, satiety, and appetite control. Thus, they might constitute meaningful biomarkers in longitudinal and interventional studies on eating behavior and body weight control. However, little is known about the physiological levels of GIHs, their intra-individual stability over time, and their interaction with other metabolic and lifestyle-related parameters. Therefore, the aim of this pilot study is to investigate the intra-individual stability of GIHs in normal-weight adults over time. Methods: Plasma concentrations of ghrelin, leptin, GLP-1 (glucagon-like-peptide), and PP (pancreatic polypeptide) were assessed by enzyme-linked immunosorbent assay (ELISA) in 17 normal-weight, healthy adults in a longitudinal design at baseline and at follow-up six months later. The reliability of the measurements was estimated using intra-class correlation (ICC). In a second step, we considered the stability of GIH levels after controlling for changes in blood glucose and hemoglobin A1 (HbA1c) as well as self-reported physical activity and dietary habits. Results: We found excellent reliability for ghrelin, good reliability for GLP1 and PP, and moderate reliability for leptin. After considering glucose, HbA1c, physical activity, and dietary habits as co-variates, the reliability of ghrelin, GLP1, and PP did not change significantly; the reliability of leptin changed to poor reliability. Conclusions: The GIHs ghrelin, GLP1, and PP demonstrated good to excellent test–retest reliability in healthy individuals, a finding that was not modified after adjusting for glucose control, physical activity, or dietary habits. Leptin showed only moderate to poor reliability, which might be linked to weight fluctuations, albeit small, between baseline and follow-up assessment in our study sample. Together, these findings support that ghrelin, GLP1, and PP might be further examined as biomarkers in studies on weight control, with GLP1 and PP serving as anorexic markers and ghrelin as an orexigenic marker. Additional reliability studies in obese individuals are necessary to verify or refute our findings for this cohort.

Nanocarriers for oral delivery of biologics: small carriers for big payloads

Macromolecular therapeutics of biological origin, also known as biologics, have become one of the fastest-growing classes of drugs for management of a range of chronic and acute conditions. The majority of approved biologics are administered via the parenteral route and are thus expensive, have low patient compliance, and have high systemic toxicity. Therefore, tremendous efforts have been devoted to the development of carriers for oral delivery of biologics. This review evaluates key chemical (e.g. pH and enzymes) and physiological challenges to oral biologics delivery. We review the conventional formulation strategies and their limitations, followed by a detailed account of the progress on the use of nanocarriers used for oral biologics delivery, covering organic and inorganic nanocarriers. Lastly, we discuss limitations and opportunities presented by these emerging nanomaterials in oral biologics delivery.

Action Mode of Gut Motility, Fluid and Electrolyte Transport in Chronic Constipation

Chronic constipation is a common gastrointestinal disorder, with a worldwide incidence of 14–30%. It negatively affects quality of life and is associated with a considerable economic burden. As a disease with multiple etiologies and risk factors, it is important to understand the pathophysiology of chronic constipation. The purpose of this review is to discuss latest findings on the roles of gut motility, fluid, and electrolyte transport that contribute to chronic constipation, and the main drugs available for treating patients. We conducted searches on PubMed and Google Scholar up to 9 February 2021. MeSH keywords “constipation”, “gastrointestinal motility”, “peristalsis”, “electrolytes”, “fluid”, “aquaporins”, and “medicine” were included. The reference lists of searched articles were reviewed to identify further eligible articles. Studies focusing on opioid-induced constipation, evaluation, and clinic management of constipation were excluded. The occurrence of constipation is inherently connected to disorders of gut motility as well as fluid and electrolyte transport, which involve the nervous system, endocrine signaling, the gastrointestinal microbiota, ion channels, and aquaporins. The mechanisms of action and application of the main drugs are summarized; a better understanding of ion channels and aquaporins may be helpful for new drug development. This review aims to provide a scientific basis that can guide future research on the etiology and treatment of constipation.

How did the ancient bacterium, Helicobacter pylori, cause an epidemic of chronic duodenal ulceration?

The association of Helicobacter pylori with chronic duodenal ulceration was a seminal observation in the short history of gastroenterology. However, H. pylori is now known to be an ancient bacterium, whereas there is persuasive evidence that the epidemic of duodenal ulceration began in the second half of the 19th century and continued into the second half of the 20th century. Possible explanations for the epidemic include genomic changes in the organism and environmental or other influences on the human host. While genomic changes resulted in the appearance of virulence factors, these seem likely to have appeared thousands of years ago with minimal effects on gastritis because of coexisting suppression of gastric immunity. In contrast, the emergence of duodenal ulceration is best explained by a change in the pattern of gastritis from inflammation involving the antrum and body in most individuals to a significant minority (10-20%) with antral gastritis but with relative sparing of the body of the stomach. In the latter group, the increase in serum gastrin (particularly G17) associated with antral gastritis had trophic effects on gastric parietal cells with an increase in the parietal cell mass and hypersecretion of gastric acid. Hypersecretion of acid is seen as the major risk factor for duodenal ulceration with significant contributions from environmental factors including smoking and use of nonsteroidal, anti-inflammatory drugs. Host factors favoring changes in the pattern of gastritis include delayed acquisition of infection and improved nutrition; both with enhancing effects on mucosal immunity.

Effects of the herbal medicine Rikkunshito, for functional dyspepsia: A systematic review and meta-analysis

BACKGROUND AND AIM

Functional dyspepsia (FD) is characterized by chronic and unexplained indigestion at upper abdomen. Because of unsatisfactory effect of conventional treatments, demand is growing for complementary and alternative medicine. Rikkunshito (RKT) is a herbal medicine, which has been widely used for FD in Asia; however, the evidence is lacking. We carried out systematic review and meta-analysis to evaluate the effect and safety of RKT in the treatment of FD.

METHODS

Electronic databases were searched in April 2019, including PUBMED, EMBASE, and Cochrane Library. All eligible studies should be randomized controlled trials (RCTs) comparing RKT or combination therapy (RKT and western medicine) group to western medicine group. The primary outcome measure was the total clinical efficacy rate (TCE). The secondary outcomes were total dyspepsia symptom scale, gastric emptying rate, gastrin, motilin, recurrence 6 months after treatment, and Hamilton depression rating scale.

RESULTS

Fifty-two RCTs with 5475 patients were involved in this systematic review and meta-analysis. Compared with western medicine, RKT showed significant better result, with higher TCE (relative risk = 1.21, 95% confidence interval 1.17 to 1.25, P < 0.001). RKT presented higher reduction of total dyspepsia symptom scale, more improved gastric emptying rate, and lower recurrence 6 months after treatment compared with western medicine. However, there was no significant difference in Hamilton depression rating scale between RKT and western medicine group. Combination therapy brought significant symptom improvement with TCE compared with western medicine alone.

CONCLUSIONS

Rikkunshito and combination therapy might be considered an effective alternative treatment for FD. Further rigorously designed and high-quality RCTs are needed.