Agents that act luminally to treat diarrhoea and constipation

Diagnostic and therapeutic approach to children with chronic refractory constipation: Consensus report by the SIGENP motility working group

Constipation is a common problem in children, accounting for about 3% of all primary care visits and up to 25% of referrals to paediatric gastroenterologists. Although polyethylene glycol often proves effective, most children require prolonged treatment and about 50% of them have at least one relapse within the first 5 years after initial recovery. When conventional treatment fails, children are considered to have refractory constipation. Children with refractory constipation deserve specialist management and guidance. Over the last decades, there has been a remarkable increase in our knowledge of normal and abnormal colonic and anorectal motility in children, and a number of different techniques to measure transit and motility have been developed. The present review analyses the possible diagnostic investigations for children with refractory constipation, focusing on their actual indications and their utility in clinical practice. Moreover, we have also analytically reviewed medical and surgical therapeutic options, which should be considered in selected patients in order to achieve the best clinical outcome.

NIR-II and visible fluorescence hybrid imaging-guided surgery via aggregation-induced emission fluorophores cocktails

Fluorescence imaging-guided surgery is one of important techniques to realize precision surgery. Although second near-infrared window (NIR-II) fluorescence imaging has the advantages of high resolution and large penetration depth in surgical navigation, its major drawback is that NIR-II images cannot be detected by our naked eyes, which demands a high hand-eye coordination for surgeons and increases the surgical difficulty. On the contrary, visible fluorescence can be observed by our naked eyes but has poor penetration. Here, we firstly propose a kind of NIR-II and visible fluorescence hybrid navigation surgery assisted via a cocktail of aggregation-induced emission nanoparticles (AIE NPs). NIR-II imaging helps to locate deep targeted tissues and judge the residual, and visible fluorescence offers an easily surgical navigation. We apply this hybrid navigation mode in different animals and systems, and verify that it can accelerate surgical process and compatible with a visible fluorescence endoscopy. To deepen the understanding of lymph node (LN) labelling, the distribution of NPs in LNs after local administration is initially analyzed by NIR-II fluorescence wide-filed microscopy, and two fates of the NPs are summarized. An alternative strategy which combines indocyanine green and berberine is also reported as a compromise for rapidly clinical translation.

Neurogenic Bowel and Management after Spinal Cord Injury: A Narrative Review

People with spinal cord injury (SCI) suffer from the sequela of neurogenic bowel and its disabling complications primarily constipation, fecal incontinence, and gastrointestinal (GI) symptoms. Neurogenic bowel is a functional bowel disorder with a spectrum of defecatory disorders as well as colonic and gastrointestinal motility dysfunction. This manuscript will review the anatomy and physiology of gastrointestinal innervation, as well as the pathophysiology associated with SCI. It will provide essential information on the recent guidelines for neurogenic bowel assessment and medical management. This will allow medical providers to partner with their patients to develop an individualized bowel plan utilizing a combination of various pharmacological, mechanical and surgical interventions that prevent complications and ensure successful management and compliance. For people with SCI and neurogenic bowel dysfunction, the fundamental goal is to maintain health and well-being, promote a good quality of life and support active, fulfilled lives in their homes and communities.

Berberine and Cisplatin Exhibit Synergistic Anticancer Effects on Osteosarcoma MG-63 Cells by Inhibiting the MAPK Pathway

Berberine (BBR) has been reported to have potent anticancer activity and can increase the anticancer effects of chemotherapy drugs. The present study aims to investigate whether BBR and cisplatin (DDP) exert synergistic effects on the osteosarcoma (OS) MG-63 cell line. In the present study, MG-63 cells were treated with BBR and DDP alone or in combination. The effects of these therapeutics on cell viability, colony formation, migration, invasion, nuclear morphology, apoptosis, and the cell cycle, as well as their role in regulating the expression of proteins related to apoptosis, the cell cycle, and the mitogen-activated protein kinase (MAPK) pathway, were determined. The results demonstrated that BBR or DDP significantly inhibited the proliferation of MG-63 cells in a dose- and time-dependent manner. The combination treatment of BBR and DDP exerted a prominent inhibitory effect on proliferation and colony formation. Furthermore, the results showed that the combination treatment of BBR and DDP enhanced the inhibition of cell migration and invasion and reversed the changes in nuclear morphology. The results showed that the combination treatment of BBR and DDP induced apoptosis and cell cycle arrest in the G0/G1 phase. Mechanistically, the combination treatment of BBR and DDP inhibited the expression of MMP-2/9, Bcl-2, CyclinD1, and CDK4, enhanced the expression of Bax and regulated the activity of the MAPK pathway. Collectively, our data suggest that the combination therapy of BBR and DDP markedly enhanced OS cell death.

The different effects of Chinese Herb Solid Drink and lactulose on gut microbiota in rats with slow transit constipation induced by compound diphenoxylate

Slow transit constipation (STC) has become an epidemic medical problem. There are several kinds of drugs for constipation; however, each drug has its limitations. The gut microbiota has a close relationship with STC. Lactulose is an effective drug for constipation because it is a kind of bulking laxative and microbioecologic, and it relieves the syndromes of STC. We found that the Chinese Herb Solid Drink (CHSD), which contains medicine food homologous materials such as psyllium husk, sweetalmond, semen sesami nigrum, and hemp seed, has a similar effect on relieving constipation as lactulose, although it has different effects on the gut microbiota. We investigated the mechanisms of CHSD in rats with STC, induced by diphenoxylate, via constipation index and enzyme linked immunosorbent assay (ELISA) analyses using serum and 16S rDNA amplicon and gas chromatography-mass spectroscopy (GC-MS). CHSD enhanced the relative abundance of some types of gut microbiota, such as Blautia, Ruminococcus, Roseburia, Coprococcus, Lachnospira, and Phascolarctobacterium, while lactulose enhanced the relative abundance of Blautia, Phascolarctobacterium, Eubacterium, and Akkernansia in diphenoxylate-induced STC rats. Both CHSD and lactulose enhanced the level of short-chain fatty acids in the faeces of rats; however, the composition of those were different between the two drugs. From the perspective of the gut neuroendocrine system, both CHSD and lactulose could elevate neurotransmitters, such as motilin (MTL) and substance P (SP), which promote intestinal peristalsis and reduce the expression of vasoactive intestinal peptide, which inhibits intestinal peristalsis in the serum of STC rats. CHSD could elevate gastrin expression, which also promoted intestinal peristalsis in serum, while lactulose did not have this effect. Our findings suggest that CHSD may be an effective and safe therapeutic choice for STC.

Diagnosing Constipation Spectrum Disorders in a Primary Care Setting

Understanding pathophysiological causes of constipation is worthwhile in directing therapy and improving symptoms. This review aims to identify and fill gaps in the understanding of the pathophysiology of constipation, understand its prevalence, review diagnostic tools available to primary care physicians (PCPs), and highlight patients’ expectations for the management of this common spectrum of disorders. Literature searches conducted via PubMed included terms related to constipation, diagnosis, and patient perceptions. Case studies were developed to highlight the differences between patients who may be appropriately managed in the primary care setting and those requiring specialty consultation. Myriad pathophysiological factors may contribute to constipation, including stool consistency, altered intestinal motility, gut microbiome, anorectal abnormalities, as well as behavioral and psychological factors. Common diagnoses of “primary constipation” include slow-transit constipation, defecation disorders, irritable bowel syndrome with constipation, and chronic idiopathic constipation. A detailed medical history should be conducted to exclude alarm features and PCPs should be familiar with pathophysiological factors that cause constipation, available diagnostic tools, alarm signs, and the various classification criteria for constipation subtypes in order to diagnose and treat patients accordingly. PCPs should understand when a referral to a gastroenterologist, anorectal specialist, pelvic floor physical therapist, and/or mental health specialist is appropriate.

Laxative effect and mechanism of Tiantian Capsule on loperamide-induced constipation in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Tiantian capsule (TTC), as a functional food, which consists of four herb medicines, including Aloe vera Burm.f. (25%), leaf juices, dried; Cucurbita moschata Duch. (25%), fructus, dried; Poria cocos (Schw.) Wolf. (12.5%), sclerotium, dried; Tremella fuciformis Berk. (12.5%), fruiting bodies, dried, and one extract xylooligosaccharides (25%) from Maize Cob by enzymolysis, has been commonly used in China to ameliorate constipation.

AIM OF THE STUDY

The aim of the work is to elucidate the potential laxative mechanisms of TTC in loperamide-induced constipated rats.

MATERIALS AND METHODS

LC-MS/MS was employed for analyzing the TTC extract. The gastrointestinal transit was evaluated by X-ray. The H&E and Alcian-Blue stain were applied to determine the changes of goblet cells and mucus layer, respectively. Meanwhile, levels of neurotransmitters were evaluated by enzyme-linked immunosorbent assay. The protein expressions were also measured by immunohistochemistry and Western blot.

RESULTS

Our results showed that TTC administration attenuated constipation responses in aspects of fecal pellets number, water content of feces, stomach emptying and gastrointestinal transit. Further investigations revealed that TTC treatment not only induced the recovery of neurotransmitters, such as motilin, substance P, somatostatin, endothelin and vasoactive intestinal peptide, but also up-regulated the expressions of c-kit and stem cell factor (SCF). Additionally, the number of goblet cells and thickness of the mucus layer were elevated, and the guanylate cyclase C-cGMP signal pathway was also up-regulated after TTC treatment.

CONCLUSION

Our findings demonstrated that the laxative effect of TTC in constipation rats is probably due to the regulation of bowel movement and intestinal fluid secretion.

Berberine alters gut microbial function through modulation of bile acids

BACKGROUND

Berberine (BBR) is a plant-based nutraceutical that has been used for millennia to treat diarrheal infections and in contemporary medicine to improve patient lipid profiles. Reduction in lipids, particularly cholesterol, is achieved partly through up-regulation of bile acid synthesis and excretion into the gastrointestinal tract (GI). The efficacy of BBR is also thought to be dependent on structural and functional alterations of the gut microbiome. However, knowledge of the effects of BBR on gut microbiome communities is currently lacking. Distinguishing indirect effects of BBR on bacteria through altered bile acid profiles is particularly important in understanding how dietary nutraceuticals alter the microbiome.

RESULTS

Germfree mice were colonized with a defined minimal gut bacterial consortium capable of functional bile acid metabolism (Bacteroides vulgatus, Bacteroides uniformis, Parabacteroides distasonis, Bilophila wadsworthia, Clostridium hylemonae, Clostridium hiranonis, Blautia producta; B4PC2). Multi-omics (bile acid metabolomics, 16S rDNA sequencing, cecal metatranscriptomics) were performed in order to provide a simple in vivo model from which to identify network-based correlations between bile acids and bacterial transcripts in the presence and absence of dietary BBR. Significant alterations in network topology and connectivity in function were observed, despite similarity in gut microbial alpha diversity (P = 0.30) and beta-diversity (P = 0.123) between control and BBR treatment. BBR increased cecal bile acid concentrations, (P < 0.05), most notably deoxycholic acid (DCA) (P < 0.001). Overall, analysis of transcriptomes and correlation networks indicates both bacterial species-specific responses to BBR, as well as functional commonalities among species, such as up-regulation of Na+/H+ antiporter, cell wall synthesis/repair, carbohydrate metabolism and amino acid metabolism. Bile acid concentrations in the GI tract increased significantly during BBR treatment and developed extensive correlation networks with expressed genes in the B4PC2 community.

CONCLUSIONS

This work has important implications for interpreting the effects of BBR on structure and function of the complex gut microbiome, which may lead to targeted pharmaceutical interventions aimed to achieve the positive physiological effects previously observed with BBR supplementation.

The influence of probiotics on bile acids in diseases and aging

Recent evidence indicates the use of probiotics in the prevention and treatment of diseases. Probiotics are capable of changing the gut microbiota composition and bile acid synthesis to elicit health benefits such as cholesterol-lowering, weight reduction, and improving insulin sensitivity. The aging population is prone to develop diseases because of their decreased physiological and biological systems. Probiotics are one of the promising supplements that may potentially counteract these detrimental effects. This review will discuss the influence of probiotics on bile acids in different populations-the elderly, obese individuals, and those with hypercholesterolemia, type 2 diabetes, hypertension, and non-alcoholic fatty liver disease.

Berberine for prevention of dementia associated with diabetes and its comorbidities: A systematic review

BACKGROUND

A growing number of epidemiological studies indicate that metabolic syndrome (MetS) and its associated features play a key role in the development of certain degenerative brain disorders, including Alzheimer's disease and vascular dementia. Produced by several different medicinal plants, berberine is a bioactive alkaloid with a wide range of pharmacological effects, including antidiabetic effects. However, it is not clear whether berberine could prevent the development of dementia in association with diabetes.

OBJECTIVE

To give an overview of the therapeutic potential of berberine as a treatment for dementia associated with diabetes.

SEARCH STRATEGY

Database searches A and B were conducted using PubMed and ScienceDirect. In search A, studies on berberine's antidementia activities were identified using "berberine" and "dementia" as search terms. In search B, recent studies on berberine's effects on diabetes were surveyed using "berberine" and "diabetes" as search terms.

INCLUSION CRITERIA

Clinical and preclinical studies that investigated berberine's effects associated with MetS and cognitive dysfunction were included.

DATA EXTRACTION AND ANALYSIS

Data from studies were extracted by one author, and checked by a second; quality assessments were performed independently by two authors.

RESULTS

In search A, 61 articles were identified, and 22 original research articles were selected. In search B, 458 articles were identified, of which 101 were deemed relevant and selected. Three duplicates were removed, and a total of 120 articles were reviewed for this study. The results demonstrate that berberine exerts beneficial effects directly in the brain: enhancing cholinergic neurotransmission, improving cerebral blood flow, protecting neurons from inflammation, limiting hyperphosphorylation of tau and facilitating β-amyloid peptide clearance. In addition, evidence is growing that berberine is effective against diabetes and associated disorders, such as atherosclerosis, cardiomyopathy, hypertension, hepatic steatosis, diabetic nephropathy, gut dysbiosis, retinopathy and neuropathy, suggesting indirect benefits for the prevention of dementia.

CONCLUSION

Berberine could impede the development of dementia via multiple mechanisms: preventing brain damages and enhancing cognition directly in the brain, and indirectly through alleviating risk factors such as metabolic dysfunction, and cardiovascular, kidney and liver diseases. This study provided evidence to support the value of berberine in the prevention of dementia associated with MetS.

Effect of Repeated Consumption of Partially Hydrolyzed Guar Gum on Fecal Characteristics and Gut Microbiota: A Randomized, Double-Blind, Placebo-Controlled, and Parallel-Group Clinical Trial

Partially hydrolyzed guar gum (PHGG) is a water-soluble dietary fiber and is used in solid and liquid food to regulate gut function. The aim of this study was to investigate effects of PHGG on bowel movements (stool form and frequency), plasma bile acids, quality of life, and gut microbiota of healthy volunteers with a tendency toward diarrhea, i.e., irritable bowel syndrome diarrhea (IBS-D)-like symptoms. A randomized, double-blind, placebo-controlled, and parallel trial was performed on 44 healthy volunteers (22 males, 22 females, 41.9 ± 6.3 years old (average ± SD)) with minimum 7 bowel movements every week, wherein above 50% of their stool was between the Bristol stool scale (BSS) value of 5 and 6. Intake of the PHGG for 3 months significantly improved stool form, evaluated using BSS, and had no effects on stool frequency. BSS was significantly normalized in the group consuming the PHGG compared with the placebo. Comprehensive fecal microbiome analysis by the 16S rRNA-sequence method detected significant changes in the ratio of some bacteria, such as an increase of Bifidobacterium (p < 0.05) in the PHGG group. Our results suggest that intake of PHGG improves human stool form via regulating intestinal microbiota.

Berberine in combination with cisplatin induces necroptosis and apoptosis in ovarian cancer cells

Background

Berberine (BBR), a compound extracted from a variety of medicinal herbs, has been shown multiple pharmacological effects against cancer cells of different origins. Cisplatin (DDP) is known as an effective chemotherapeutic agent against cancer by inducing DNA damage and cell apoptosis. However, the effect of the combined used of BBR and DDP on cell necroptosis in ovarian cancer has not been reported.

Methods

OVCAR3 and three patient-derived primary ovarian cancer cell lines (POCCLs) were chosen as the experimental objects. To determine the potential anti-cancer activity of BBR and DDP in combination, we firstly treated OVCAR3 and POCCLs cells with BBR and/or DDP. The cell viability of OVCAR3 and POCCLs with treatment of BBR or DDP for different hours was measured by CCK-8 assay. Flow cytometry was used to analyze cell cycle distribution and changes in apoptotic cells after treatment with BBR and/or DDP. The morphological changes of OVCAR3 cells were observed by using Transmission electron microscopy (TEM) analysis. Proliferation, apoptosis and necroptosis related markers of OVCAR3 and POCCLs with treatment of BBR or DDP were measured by RT-qPCR, western blotting and immunofluorescence assay.

Results

Our results demonstrated that BBR significantly inhibited the proliferation of OVCAR3 and primary ovarian cancer cells in a dose- and time-dependent manner. The combination treatment of BBR and DDP had a prominent inhibitory effect on cancer cell growth and induced G0/G1 cell cycle arrest. TEM revealed that the majority of cells after BBR or DDP treatment had an increasing tendency of typical apoptotic and necrotic cell death morphology. Besides, BBR and DDP inhibited the expression of PCNA and Ki67 and enhanced the expression and activation of Caspase-3, Caspase-8, RIPK3 and MLKL.

Conclusion

This study proposed that the combination therapy of BBR and DDP markedly enhanced more ovarian cancer cell death by inducing apoptosis and necroptosis, which may improve the anticancer effect of chemotherapy drugs. The apoptosis involved the caspase-dependent pathway, while the necroptosis involved the activation of the RIPK3–MLKL pathway. We hope our findings might provide a new insight for the potential of BBR as a therapeutic agent in the treatment of ovarian cancer.

A Microbiota-Derived Bacteriocin Targets the Host to Confer Diarrhea Resistance in Early-Weaned Piglets

Alternatives to antibiotics for preventing diarrhea in early-weaned farm animals are sorely needed. CM piglets (a native Chinese breed) are more resistant to early-weaning stress-induced diarrhea than the commercial crossbred LY piglets. Transferring fecal microbiota, but not saline, from healthy CM into LY piglets by oral administration prior to early weaning conferred diarrhea resistance. By comparing the relative abundance of intestinal microbiota in saline and microbiota transferred LY piglets, we identified and validated Lactobacillus gasseri LA39 and Lactobacillus frumenti as two bacterial species that mediate diarrhea resistance. Diarrhea resistance depended on the bacterial secretory circular peptide gassericin A, a bacteriocin. The binding of gassericin A to Keratin 19 (KRT19) on the plasma membrane of intestinal epithelial cells was essential for enhancement of fluid absorption and decreased secretion. These findings suggest the use of L. gasseri LA39 and L. frumenti as antibiotic alternatives for preventing diarrhea in mammals.

A Novel Method to Mask the Bitter Taste of Berberine Hydrochloride: Powder Surface Modification

Background:

Berberine hydrochloride (BH) is widely used as a nonprescription drug to treat diarrhea without drug resistance and side effects worldwide. However, its drastic bitterness affects patient compliance severely. Hence, it is essential to mask the bitter taste of BH.

Objective:

Powder surface modification technology is attempted to mask the bitterness of BH through changing the surface properties in vibromill. The purpose of this study was to apply this technology to mask the bitterness of BH and improve the patient compliance.

Materials and Methods:

Initially, to prepare the modifier-BH composites, some parameters were optimized, including type of modifiers, ratio between BH and modifiers, and composite time. Then, the contact angles, scanning electron microscopy, and infrared (IR) spectroscopy were utilized to evaluate the microstructure of composites. Moreover, electronic tongue measurement, animal performance test, and bitterness evaluation methods were applied to evaluate the masking effect.

Results:

Based on the results of bitter taste evaluations, mannitol was chosen as the best modifier, and the optimal ratio of BH and mannitol was 6:4 with grinding together for 2 min in vibromill. For the composites prepared by this process, the IR spectroscopy and surface properties were similar with that of mannitol, and the microstructure was also demonstrated that small particles of mannitol successfully coated on the surface of BH. Special structure of the composites decreased the contact area between BH and external media and finally inhibited the bitterness. This effect was confirmed by three different kinds of methods.

Conclusion:

Our study provides a novel method to mask the bitter taste of drugs. It will be of great interest to pharmaceutical experts and pharmacists.

SUMMARY

Powder surface modification, a novel and different from previous technology, is used to prepare modifier-berberine hydrochloride composites to mask the bitter taste of BH

Electronic tongue measurement, animal performance test, human sensory test, and chemical evaluation method were simultaneously applied to evaluate the masking effect

A novel method to mask the bitter taste of drugs was provided.

Abbreviations used: BH:Berberine hydrochloride; CDI: Clostridium difficile infection; ODT: Orally disintegrating tablets; HPLC: High-performance liquid chromatography; CAs: Contact angles; SEM: Scanning electron microscopy; IR: Infrared spectrogram.

Berberine inhibits EGFR signaling and enhances the antitumor effects of EGFR inhibitors in gastric cancer

Cetuximab plus chemotherapy for advanced gastric cancer (GC) shows an active result in phase 2 trials. Unfortunately, Combination of cetuximab does not provide enough benefit to chemotherapy alone in phase 3 trials. Studies have demonstrated that berberine can suppress the activation of EGFR in tumors. In this study, we evaluated whether berberine could enhance the effects of EGFR-TKIs in GC cell lines and xenograft models. Our data suggest that berberine could effectively enhance the activity of erlotinib and cetuximab in vitro and in vivo. Berberine was found to inhibit growth in GC cell lines and to induce apoptosis. These effects were linked to inhibition of EGFR signaling activation, including the phosphorylation of STAT3. The expressions of Bcl-xL and Cyclind1 proteins were decreased, whereas the levels of cleavage of poly-ADP ribose polymerase (PARP) were considerably increased in the cell lines in response to berberine treatment. These results suggest a potential role for berberine in the treatment of GC, particularly in combination with EGFR-TKIs therapy. Berberine may be a competent therapeutic agent in GC where it can enhance the effects of EGFR inhibitors.

Luminally Acting Agents for Constipation Treatment: A Review Based on Literatures and Patents

Constipation is one of the most frequently reported gastrointestinal (GI) disorders that negatively impacts quality of life and is associated with a significant economic burden to the patients and society. Traditional treatments including lifestyle modification and laxatives are often ineffective in the more severe forms of constipation and over the long term. New medications targeting at intestinal chloride channels and colonic serotonin receptors have been demonstrated effective in recent years. Emerging agents focusing on improving intestinal secretion and/or colonic motility have been shown effective in animal models and even in clinical trials. Recognization of the role of cystic fibrosis transmembrane regulator (CFTR) and calcium-activated chloride channels (CaCCs) in intestine fluid secretion and motility modulation makes CFTR and CaCCs promising molecule targets for anti-constipation therapy. Although there are multiple choices for constipation treatment, there is still a recognized need for new medications in anti-constipation therapy. The present review covers the discovery of luminally acting agents for constipation treatment described in both patents (2011–present) and scientific literatures.

Phenylquinoxalinone CFTR activator as potential prosecretory therapy for constipation

Constipation is a common condition for which current treatments can have limited efficacy. By high-throughput screening, we recently identified a phenylquinoxalinone activator of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel that stimulated intestinal fluid secretion and normalized stool output in a mouse model of opioid-induced constipation. Here, we report phenylquinoxalinone structure-activity analysis, mechanism of action, animal efficacy data in acute and chronic models of constipation, and functional data in ex vivo primary cultured human enterocytes. Structure-activity analysis was done on 175 phenylquinoxalinone analogs, including 15 synthesized compounds. The most potent compound, CFTRact-J027, activated CFTR with EC50 ∼ 200 nM, with patch-clamp analysis showing a linear CFTR current-voltage relationship with direct CFTR activation. CFTRact-J027 corrected reduced stool output and hydration in a mouse model of acute constipation produced by scopolamine and in a chronically constipated mouse strain (C3H/HeJ). Direct comparison with the approved prosecretory drugs lubiprostone and linaclotide showed substantially greater intestinal fluid secretion with CFTRact-J027, as well as greater efficacy in a constipation model. As evidence to support efficacy in human constipation, CFTRact-J027 increased transepithelial fluid transport in enteroids generated from normal human small intestine. Also, CFTRact-J027 was rapidly metabolized in vitro in human hepatic microsomes, suggesting minimal systemic exposure upon oral administration. These data establish structure-activity and mechanistic data for phenylquinoxalinone CFTR activators, and support their potential efficacy in human constipation.

AMPK/α-Ketoglutarate Axis Regulates Intestinal Water and Ion Homeostasis in Young Pigs

Water and ion absorption via sensitive aquaporins (AQPs) and ion channels is of critical importance in intestinal health. However, whether α-ketoglutarate (AKG) could improve intestinal water and ion homeostasis in lipopolysaccharide (LPS)-challenged piglets and whether the AMP-activated protein kinase (AMPK) pathway is involved remains largely unknown. This study was conducted to investigate the effect of dietary AKG supplementation on the small intestinal water and ion homeostasis through modulating the AMPK pathway in a piglet diarrhea model. A total of 32 weaned piglets were used in a 2 × 2 factorial design; the major factors were diet (basal diet or 1% AKG diet) and challenge (Escherichia coli LPS or saline). The results showed that LPS challenge increased the diarrhea index and affected the concentrations of serum Na⁺, K⁺, Cl^-, glucose, and AKG and its metabolites in piglets fed the basal or AKG diet. However, the addition of AKG attenuated diarrhea incidence and reversed these serum parameter concentrations. Most AQPs (e.g., AQP1, AQP3, AQP4, AQP5, AQP8, AQP10, and AQP11) and ion transporters (NHE3, ENaC, and DRA/PAT1) were widely distributed in the duodenum and jejunum of piglets. We also found that AKG up-regulated the expression of intestinal epithelial AQPs while inhibiting the expression of ion transporters. LPS challenge decreased (P < 0.05) the gene and protein expression of the AMPK pathway (AMPKα1, AMPKα2, SIRT1, PGC-1α, ACC, and TORC2) in the jejunum and ileum. Notably, AKG supplementation enhanced the abundance of these proteins in the LPS-challenged piglets. Collectively, AKG plays an important role in increasing water and ion homeostasis through modulating the AMPK pathway. Our novel finding has important implications for the prevention and treatment of gut dysfunction in neonates.

Polyethylene glycol 400 (PEG400) affects the systemic exposure of oral drugs based on multiple mechanisms: taking berberine as an example

High concentrations of PEG400 increase in vivo exposure to berberine (D) by increasing its solubility (A), permeability (B), and lymphatic transport (C).

Antiproliferation of berberine is mediated by epigenetic modification of constitutive androstane receptor (CAR) metabolic pathway in hepatoma cells

Constitutive androstane receptor (CAR) regulates hepatic xenobiotic and energy metabolism, as well as promotes cell growth and hepatocarcinogenesis. Berberine is an ancient multipotent alkaloid drug which derived from Coptis chinensis plants. Here we report that berberine is able to be cellular uptake and accessible to chromatin in human hepatoma HepG2 cells. Berberine induces more apoptosis, cell cycle arrest, but less ROS production in CAR overexpressed mCAR-HepG2 cells. Moreover, berberine inhibits expressions of CAR and its target genes CYP2B6 and CYP3A4. Furthermore, berberine enhances DNA methylation level in whole genome but reduces that in promoter regions CpG sites of CYP2B6 and CYP3A4 genes under the presence of CAR condition. These results indicated that the antiproliferation of berberine might be mediated by the unique epigenetic modifying mechanism of CAR metabolic pathway, suggesting that berberine is a promising candidate in anticancer adjuvant chemotherapy, due to its distinct pharmacological properties in clinic.

Significant pharmacokinetic differences of berberine are attributable to variations in gut microbiota between Africans and Chinese

We investigated the influence of gut microbiotal metabolism on the pharmacokinetics of berberine in healthy male Africans and Chinese. The Cmax and AUC in the Africans were 2.67-fold and 2.0-fold higher than the Chinese, respectively. Microbiotal compositions by 16S rRNA pyrosequencing showed higher abundance of the genera Prevotella, Bacteroides, and Megamonas (34.22, 13.88, and 10.68%, respectively) in the Chinese than the Africans (30.08, 9.43, and 0.48%, respectively). Scatter plot showed a strong negative correlation between the microbiotal abundance and the berberine AUC, especially for the genus Prevotella (r = -0.813) and its species. A more extensive metabolism was observed in Chinese with 1.83-fold higher metabolites, possibly contributing to the lower AUC than the Africans. In conclusion, significant PK differences of berberine were observed between Africans and Chinese, which is partly attributable to variations in gut microbiota and its corresponding metabolic capacity.

Anti-infective activities of lactobacillus strains in the human intestinal microbiota: from probiotics to gastrointestinal anti-infectious biotherapeutic agents

A vast and diverse array of microbial species displaying great phylogenic, genomic, and metabolic diversity have colonized the gastrointestinal tract. Resident microbes play a beneficial role by regulating the intestinal immune system, stimulating the maturation of host tissues, and playing a variety of roles in nutrition and in host resistance to gastric and enteric bacterial pathogens. The mechanisms by which the resident microbial species combat gastrointestinal pathogens are complex and include competitive metabolic interactions and the production of antimicrobial molecules. The human intestinal microbiota is a source from which Lactobacillus probiotic strains have often been isolated. Only six probiotic Lactobacillus strains isolated from human intestinal microbiota, i.e., L. rhamnosus GG, L. casei Shirota YIT9029, L. casei DN-114 001, L. johnsonii NCC 533, L. acidophilus LB, and L. reuteri DSM 17938, have been well characterized with regard to their potential antimicrobial effects against the major gastric and enteric bacterial pathogens and rotavirus. In this review, we describe the current knowledge concerning the experimental antibacterial activities, including antibiotic-like and cell-regulating activities, and therapeutic effects demonstrated in well-conducted, placebo-controlled, randomized clinical trials of these probiotic Lactobacillus strains. What is known about the antimicrobial activities supported by the molecules secreted by such probiotic Lactobacillus strains suggests that they constitute a promising new source for the development of innovative anti-infectious agents that act luminally and intracellularly in the gastrointestinal tract.

CFTR activator increases intestinal fluid secretion and normalizes stool output in a mouse model of constipation

BACKGROUND & AIMS

Constipation is a common clinical problem that negatively impacts quality of life and is associated with significant health care costs. Activation of the cystic fibrosis transmembrane regulator (CFTR) chloride channel is the primary pathway that drives fluid secretion in the intestine, which maintains lubrication of luminal contents. We hypothesized that direct activation of CFTR would cause fluid secretion and reverse the excessive dehydration of stool found in constipation.

METHODS

A cell-based high-throughput screen was done for 120,000 drug-like, synthetic small molecules. Active compounds were characterized for mechanism of action and one lead compound was tested in a loperamide-induced constipation model in mice.

RESULTS

Several classes of novel CFTR activators were identified, one of which, the phenylquinoxalinone CFTR_act-J027, fully activated CFTR chloride conductance with EC₅₀ ~ 200 nM, without causing elevation of cytoplasmic cAMP. Orally administered CFTR_act-J027 normalized stool output and water content in a loperamide-induced mouse model of constipation with ED₅₀ ~0.5 mg/kg; CFTR_act-J027 was without effect in cystic fibrosis mice lacking functional CFTR. Short-circuit current, fluid secretion and motility measurements in mouse intestine indicated a pro-secretory action of CFTR_act-J027 without direct stimulation of intestinal motility. Oral administration of 10 mg/kg CFTR_act-J027 showed minimal bioavailability, rapid hepatic metabolism and blood levels <200 nM, and without apparent toxicity after chronic administration.

CONCLUSIONS

CFTR_act-J027 or alternative small-molecule CFTR-targeted activators may be efficacious for the treatment of constipation.

A gastrointestinal anti-infectious biotherapeutic agent: the heat-treated Lactobacillus LB

Experimental in vitro and in vivo studies support the hypothesis that heat-treated, lyophilized Lactobacillus acidophilus LB cells and concentrated, neutralized spent culture medium conserve the variety of pharmacological, antimicrobial activities of the live probiotic strain against several infectious agents involved in well-established acute and persistent watery diarrhoea and gastritis. Heat-treated cells and heat-stable secreted molecules trigger multiple strain-specific activities explaining the therapeutic efficacy of L. acidophilus LB. This review discusses the current body of knowledge on the antimicrobial mechanisms of action exerted by L. acidophilus LB demonstrated in in vitro and in vivo experimental studies, and the evidence for the therapeutic efficacy of this anti-infectious biotherapeutic agent proved in randomized clinical trials for the treatment of acute and persistent watery diarrhoea associated with several intestinal infectious diseases in humans.

TATA boxes in gene transcription and poly (A) tails in mRNA stability: New perspective on the effects of berberine

Berberine (BBR) is a natural compound with variable pharmacological effects and a broad panel of target genes. We investigated berberine’s pharmacological activities from the perspective of its nucleotide-binding ability and discovered that BBR directly regulates gene expression by targeting TATA boxes in transcriptional regulatory regions as well as the poly adenine (poly (A)) tail at the mRNA terminus. BBR inhibits gene transcription by binding the TATA boxes in the transcriptional regulatory region, but it promotes higher levels of expression by targeting the poly (A) tails of mRNAs. The present study demonstrates that TATA boxes and poly (A) tails are the first and second primary targets by which BBR regulates gene expression. The final outcome of gene regulation by BBR depends on the structure of the individual gene. This is the first study to reveal that TATA boxes and poly (A) tails are direct targets for BBR in its regulation of gene expression. Our findings provide a novel explanation for the complex activities of a small molecule compound in a biological system and a novel horizon for small molecule-compound pharmacological studies.

A Randomized Clinical Trial of Berberine Hydrochloride in Patients with Diarrhea-Predominant Irritable Bowel Syndrome

We aimed to evaluate clinical symptoms in diarrhea predominant irritable bowel syndrome (IBS-D) receiving berberine hydrochloride in a randomized double-blind placebo-controlled clinical trial. Overall, 196 patients with IBS-D were recruited for this study; consequently, 132 patients randomized to receive daily 400 mg of berberine hydrochloride, delivered twice daily or placebo for 8 weeks followed by a 4-week washout period. After a 2-week run-in period, diarrhea, abdominal pain, urgent need for defecation frequency and any adverse events were recorded daily. Prior to administration of the medication and after completing the treatment, assessment of IBS symptom scores, depression and anxiety scale scores and the IBS scale for quality of life (QOL) was carried out. The effects of berberine hydrochloride on IBS-D, defined by a reduction of diarrhea frequency (P = 0.032), abdominal pain frequency (P < 0.01) and urgent need for defecation frequency (P < 0.01), were significantly more pronounced in the berberine group than the placebo group in the 8 weeks of treatment. A trend of improvement (P < 0.05) was observed with berberine hydrochloride for IBS symptom score, depression score and anxiety score and the IBSQOL, compared with placebo. At last, berberine hydrochloride was well tolerated. So we concluded that berberine hydrochloride is well tolerated and reduces IBS-D symptoms, which effectively improved patients QOL.

Constipation and Botanical Medicines: An Overview

Constipation affects 14% of the adult population globally, mainly women, and significantly impacts on health-related quality of life. The causes of constipation are mainly three: lifestyle related (functional constipation), disease related, and drug induced. Constipation can generate considerable suffering, including abdominal pain and distension, anorexia, and nausea. The value of some therapeutic measures such as increased fluid intake, physical activity, diet rich in fiber, and nutritional supplements recommended for the relief of constipation is still questionable. The treatment of constipation can be carried out not only with traditional drugs but also with herbal medicines or with nutraceuticals, which are used to prevent or treat the disorder. We have reviewed the most common botanical laxatives such as senna, cascara, frangula, aloe, and rhubarb and their use in the treatment of constipation.

Pathogenesis of human diffusely adhering Escherichia coli expressing Afa/Dr adhesins (Afa/Dr DAEC): current insights and future challenges

The pathogenicity and clinical pertinence of diffusely adhering Escherichia coli expressing the Afa/Dr adhesins (Afa/Dr DAEC) in urinary tract infections (UTIs) and pregnancy complications are well established. In contrast, the implication of intestinal Afa/Dr DAEC in diarrhea is still under debate. These strains are age dependently involved in diarrhea in children, are apparently not involved in diarrhea in adults, and can also be asymptomatic intestinal microbiota strains in children and adult. This comprehensive review analyzes the epidemiology and diagnosis and highlights recent progress which has improved the understanding of Afa/Dr DAEC pathogenesis. Here, I summarize the roles of Afa/Dr DAEC virulence factors, including Afa/Dr adhesins, flagella, Sat toxin, and pks island products, in the development of specific mechanisms of pathogenicity. In intestinal epithelial polarized cells, the Afa/Dr adhesins trigger cell membrane receptor clustering and activation of the linked cell signaling pathways, promote structural and functional cell lesions and injuries in intestinal barrier, induce proinflammatory responses, create angiogenesis, instigate epithelial-mesenchymal transition-like events, and lead to pks-dependent DNA damage. UTI-associated Afa/Dr DAEC strains, following adhesin-membrane receptor cell interactions and activation of associated lipid raft-dependent cell signaling pathways, internalize in a microtubule-dependent manner within urinary tract epithelial cells, develop a particular intracellular lifestyle, and trigger a toxin-dependent cell detachment. In response to Afa/Dr DAEC infection, the host epithelial cells generate antibacterial defense responses. Finally, I discuss a hypothetical role of intestinal Afa/Dr DAEC strains that can act as "silent pathogens" with the capacity to emerge as "pathobionts" for the development of inflammatory bowel disease and intestinal carcinogenesis.

Effect of berberine on proliferation and apoptosis of colon cancer HT-29 cells

AIM: To investigate the effect of berberine on cell proliferation in the human cancer cell line HT-29 and the underlying mechanisms.

METHODS: HT-29 cells in logarithmic growth phase were divided into a control group and a berberine group. The cells in the control group were normally cultured and cells in the berberine group were incubated with berberine (3 μmol/L). MTT assay and flow cytometry were used to examine cell proliferation and apoptotic changes in the two groups after incubation for 72 h. The mRNA expression of JAK2, STAT3, Bax and Bcl-2 was detected by RT-PCR. The changes in expression of JAK2, STAT3, p-JAK2, and p-STAT3 proteins were detected by Western blot. The activity of Caspase 3 was measured using a caspase 3 colorimetric assay kit.

RESULTS: Compared with the control group, the proliferation of HT-29 cells in the berberine group was significantly decreased (P < 0.05), but the apoptosis rate in the berberine group was significantly increased (P < 0.05). After treatment with berberine, the mRNA level of Bax was increased, the mRNA levels of Bcl-2 was decreased and the mRNA level sof JAK2 and STAT3 had no significant changes. Western blot results showed that the expression of total JAK2 and STAT3 proteins showed no significant changes (P < 0.05), the expression of p-JAK2, p-STAT3 and Bcl-2 was decreased, and the expression of Bcl-2 was increased (P < 0.05). Compared with the control group, the activity of Caspase 3 in the berberine group was significantly increased (P < 0.05).

CONCLUSION: Berberine can inhibit the proliferation and promote the apoptosis of HT-29 cells possibly through attenuating the activation of the JAK2/ STAT3 signaling pathway.

Emerging Pharmacologic Therapies for Constipation-predominant Irritable Bowel Syndrome and Chronic Constipation

Irritable bowel syndrome with constipation and chronic functional constipation are common digestive disorders that negatively impact quality of life and account for billions of dollars in health care costs. Related to the heterogeneity of pathogenesis that underlie these disorders and the failure of symptoms to reliably predict underlying pathophysiology, traditional therapies provide relief to only a subset of affected individuals. The evidence surrounding new and emerging pharmacologic treatments, which include both luminally and systemically acting drugs, is discussed here. These include agents such as lubiprostone, bile acid modulations, guanylate cyclase-C receptor agonists, serotonin receptor modulators and herbal therapies.

Constella™(EU)-Linzess™(USA): the last milestone in the long journey of the peptide linaclotide and its implications for the future of peptide drugs

Irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC) are highly prevalent gastrointestinal disorders associated with health, economical and social problems. Recently, after a long journey of preclinical studies and clinical trials, linaclotide, a first-in-class GC-C receptor peptide agonist, has received the approval in the USA and Europe for the treatment of IBS-C and CIC. This article provides an overview of clinical, economic and biological aspects of IBS-C and CIC and covers the current and emerging therapeutic agents for treating these conditions. Particularly, the pharmacodynamic and pharmacokinetic properties of linaclotide, a small, disulfide-rich peptide, and its implications in the future of peptide drug discovery and development are discussed.