Coptisine-induced inhibition of Helicobacter pylori: elucidation of specific mechanisms by probing urease active site and its maturation process

Efficacy and safety of Qingwei Zhitong pellets-containing quadruple therapy for eradication: a prospective, single-center, randomized trial

OBJECTIVE

To evaluate the efficacy and safety of 14-day Qingwei Zhitong pellets (, QZ)-containing quadruple therapy (QZQT) compared to bismuth-containing quadruple therapy (BQT) in treatment-naive patients with Helicobacter pylori (H. pylori) infection.

METHODS

This single-center, randomized controlled clinical trial enrolled 333 patients, who were divided into either the QZQT group (QZ pellets, 3.2 g, three times daily; rabeprazole, 10 mg, twice daily; amoxicillin 1000 mg, twice daily; clarithromycin, 500 mg, twice daily) or the BQT group (bismuth potassium citrate, 1000 mg, three times daily; rabeprazole, 10 mg, twice daily; amoxicillin, 1000 mg, twice daily; clarithromycin, 500 mg, twice daily) for 14 d. The 13C-urea breath test assessed eradication success at least four weeks after treatment. The primary outcome focused on the eradication rate, with secondary outcomes including safety and patient compliance.

RESULTS

From August 2022 to June 2023, 342 subjects were screened, and 333 were randomized. The QZQT and BQT groups showed eradication rates of 68.9% and 67.8% (P = 0.838) by intention-to-treat (ITT) analysis, respectively, and 71.1% and 68.3% (P = 0.612) by per-protocol (PP) analysis, respectively. QZQT was non-inferior to BQT in both ITT and PP analyses. QZQT was associated with fewer side effects (57.8% of patients) than BQT (90.4%) (P < 0.001).

CONCLUSION

The 14 d QZQT treatment demonstrates equal efficacy in eradicating H. pylori infection and improved patient compliance and safety compared to BQT. These results provide evidence supporting 14-day QZQT as an acceptable treatment for H. pyloriinfection.

Phytochemical analysis of dried ginger extract and its inhibitory effect and mechanism on Helicobacter pylori and associated ureases

Helicobacter pylori (H. pylori), one of the most common infectious pathogens in the world, can cause gastritis, digestive ulcers, and even gastric cancer. H. pylori urease (HPU) is a distinctive virulence factor of H. pylori that allows it to be distinguished from other pathogens. Dried ginger is a famous edible and medicinal herb that is commonly used to prevent and treat gastrointestinal tract-related diseases. In this study, phytochemical analysis of the aqueous extract of dried ginger (DGE) and the inhibition of DGE on H. pylori was investigated. Subsequently, we evaluated the inhibitory activity of DGE against enzymes including HPU and jack bean urease (JBU) and determined its potential mechanism of action. UPLC-ESI-MS/MS analysis indicated that a total of 63 compounds including seven glycosides, nine terpenoids, two esters, seven phenols, eight lignans, five phenylpropanoids, and four phenolic acids were identified in DGE. DGE was observed to inhibit the growth of four H. pylori strains (ATCC 43504, NCTC 26695, SS1, and ICDC 111001) with minimum inhibitory concentration (MIC) values spanning the range of 0.05 to 1.50 mg mL-1. Moreover, DGE has higher enzyme inhibitory activity on HPU (IC50 = 0.49 ± 0.01 mg mL-1) than on JBU (IC50 = 0.54 ± 0.01 mg mL-1). Enzyme inhibitory kinetic analysis revealed that the inhibition type of DGE against HPU was slow-binding and anti-competitive, whereas it was slow-binding and mixed type on JBU. A further mechanism study indicated that the protective effect of sulfhydryl-containing compounds on enzyme activity was significantly better than that of inorganic compounds, indicating that the action site of DGE inhibition of enzyme was the sulfhydryl residue. The results of DTT reactivation experiments showed that the DGE-urease complex was reversible. Furthermore, molecular docking investigation showed that the main components of DGE interacted with sulfhydryl groups and Ni2+. In conclusion, DGE effectively inhibited the growth of H. pylori and the activity of its key virulence factor urease. And the in-depth study of the kinetic characteristics and the mechanism of action showed that the active site sulfhydryl group and Ni2+ might be the targets of urease inhibition by DGE. Our study may provide experimental evidence for the traditional application of dried ginger in the treatment of H. pylori-associated gastric diseases.

Coptisine alleviates colitis through modulating gut microbiota and inhibiting TXNIP/NLRP3 inflammasome

ETHNOPHARMACOLOGICAL RELEVANCE

Ulcerative colitis (UC) is a disease involving the enteric canal which is characterised by chronisch inflammatory reaction. Coptisine (COP), the distinctive component of Coptis chinensis Franch., is famous for its anti-inflammation, antioxidation, anti-bacteria, and anti-cancer. Earlier researches certified that COP is a prospective remedy for colitis, but the mechanism of colitis and the therapeutical target of COP are deficiently elucidated.

AIM OF THIS STUDY

In this follow-up study, we adopted dextran sulfate sodium (DSS)-elicited UC model to further elucidate the possible mechanism of COP on UC in mice.

MATERIALS AND METHODS

COP and the positive drug sulfasalazine (SASP) were administered by oral gavage in DSS-induced colitis mouse model. Oxidative stress, inflammatory cytokines, intestinal barrier permeability, protein expression of the TXNIP/NLRP3 inflammasome pathway and intestinal microbiome structure were assessed.

RESULTS

Among this investigation, our team discovered that COP could mitigate DSS-elicited UC in murines, with prominent amelioration in weight loss, disease activity index, intestinal permeability (serum diamine oxidase and D-lactate), contracted colonal length and histologic alterations. Furthermore, COP greatly lowered the generation of pro-inflammatory factors, malondialdehyde (MDA) activity and reactive oxygen species (ROS) level, while increased superoxide dismutase (SOD) activity in colonal tissues. Additionally, COP downmodulated the proteic expressions of thioredoxin-interacting protein (TXNIP), NOD-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein (ASC), caspase-1, IL-1β and IL-18. Enteric microbiome sequencing displayed that DSS and COP tremendously influenced the constitution and diversity of enteric microbes in DSS-elicited UC murines. Besides, COP elevated the abundance of probiotic bacteria Bacteroidota, Akkermansia_muciniphila and Bacteroides_acidifaciens, lowered the proportions of potential pathogenic bacteria, such as Lachnospiraceae, Acetatifactor_muris, Clostridium_XlVa, Alistipes and Oscillibacter, and reduced the ratio of Bacillota/Bacteroidota, which vastly helped to reverse the enteric microbiome to a balanceable condition. Alterations in these bacteria were strongly correlated with the colitis relative index.

CONCLUSION

The mechanism of COP against UC is connected with the suppression of TXNIP/NLRP3 inflammasome signalling pathway and the adjustment of the enteric microbiome profiles. The proofs offer new understandings upon the anti-UC function of COP, which might be a prospective candidate against UC.

Azo derivatives of monoterpenes as anti-Helicobacter pylori agents: from synthesis to structure-based target investigation

Helicobacter pylori (Hp) infection affects nearly half of the global population. Current therapeutic options include the administration of a combination of antibiotics and proton pump inhibitors, although antimicrobial resistance rise remains a big concern. Phenolic monoterpenes, e.g., eugenol, vanillin, carvacrol, and thymol, have always attracted researchers for their multifaced biological activities and the possibility to be easily derivatized. Thereby, herein we present the functionalization of such compounds through the conventional aryl diazotization reaction, generating a series of mono- and bis-azo derivatives (1-28). Also, to continue previous studies, we investigated the role of the free phenolic moiety of thymol with eight compounds (29-36). The compounds were tested against four Hp strains including three clinical isolates, finding some potent and selective inhibitors of bacterial growth. Thus, the representative compounds underwent in vitro cytotoxicity evaluation on two normal cell lines and putative target investigation by performing a structure-based approach based on docking calculations on some of the most studied pharmacological targets for Hp, e.g., urease, β-hydroxyacyl-acyl carrier protein dehydratase, glucose 6-phosphate dehydrogenase, and inosine 5'-monophosphate dehydrogenase.

Discovery and evolution of berberine analogues as anti-Helicobacter pylori agents with multi-target mechanisms

Thirty protoberberine derivatives, of which twenty five were new, were synthesized and evaluated for their anti-Helicobacter pylori (HP) activities, taking 2,3,10-trimethoxy-9-p-methylbenzylaminoprotopalmatine chloride 1 as the lead. Among them, berberine (BBR) derivative 7c displayed the highest potency against six tested metronidazole (MTZ)-resistant strains and two tested MTZ-susceptible strains with the MIC values of 0.4-1.6 μg/mL with favorable druglike profiles including low toxicity and high stabilities in plasma and artificial gastric fluid. Mechanistic study revealed that 7c might target HP urease with IC50 value of 0.27 μg/mL against Jack bean urease. Furthermore, 7c might change the permeability of the bacterial membrane and direct interact with HP DNA, which also contribute to its bactericidal activity. Therefore, BBR derivatives constituted a new family of anti-HP candidates, with the advantage of good safety profile and multi-target mechanisms, and are worthy for further investigation.

A deep learning-driven discovery of berberine derivatives as novel antibacterial against multidrug-resistant Helicobacter pylori

Helicobacter pylori (H. pylori) is currently recognized as the primary carcinogenic pathogen associated with gastric tumorigenesis, and its high prevalence and resistance make it difficult to tackle. A graph neural network-based deep learning model, employing different training sets of 13,638 molecules for pre-training and fine-tuning, was aided in predicting and exploring novel molecules against H. pylori. A positively predicted novel berberine derivative 8 with 3,13-disubstituted alkene exhibited a potency against all tested drug-susceptible and resistant H. pylori strains with minimum inhibitory concentrations (MICs) of 0.25-0.5 μg/mL. Pharmacokinetic studies demonstrated an ideal gastric retention of 8, with the stomach concentration significantly higher than its MIC at 24 h post dose. Oral administration of 8 and omeprazole (OPZ) showed a comparable gastric bacterial reduction (2.2-log reduction) to the triple-therapy, namely OPZ + amoxicillin (AMX) + clarithromycin (CLA) without obvious disturbance on the intestinal flora. A combination of OPZ, AMX, CLA, and 8 could further decrease the bacteria load (2.8-log reduction). More importantly, the mono-therapy of 8 exhibited comparable eradication to both triple-therapy (OPZ + AMX + CLA) and quadruple-therapy (OPZ + AMX + CLA + bismuth citrate) groups. SecA and BamD, playing a major role in outer membrane protein (OMP) transport and assembling, were identified and verified as the direct targets of 8 by employing the chemoproteomics technique. In summary, by targeting the relatively conserved OMPs transport and assembling system, 8 has the potential to be developed as a novel anti-H. pylori candidate, especially for the eradication of drug-resistant strains.

From lab to nature: Recent advancements in the journey of gastroprotective agents from medicinal chemistry to phytotherapy

Peptic ulcer, affecting 10 % of the global population, results from imbalances in gastric juice pH and diminished mucosal defences. Key underlying factors are non-steroidal anti-inflammatory drugs (NSAIDs) and Helicobacter pylori infection, undermining mucosal resistance. Traditional treatments like proton pump inhibitors (PPIs) and histamine-2 (H2) receptor antagonists exhibit drawbacks such as adverse effects, relapses, and drug interactions. This review extensively explores the ethnomedicinal, synthetic and pharmacological facets of various potential peptic ulcer treatments. Rigorous methodologies involving electronic databases, and chemical structure verification via 'PubChem' and 'SciFinder' enhance the review's credibility. The provided information, spanning medicinal insights to intricate pharmacological mechanisms, establishes a robust groundwork for future research and the development of plant-derived or synthetic molecules for peptic ulcers, offering a promising alternative to conventional therapies.

Loureirin A is a narrow-spectrum antimicrobial agent against Helicobacter pylori

Currently, Helicobacter pylori eradication by antibiotic therapy faces various challenges, including antibiotic resistance, side effects on intestinal commensal bacteria, and patient compliance. In this study, loureirin A (LrA), a traditional Chinese medicine monomer extracted from Sanguis Draconis flavones, was found to possess specific antibacterial activity against H. pylori without the bacteria displaying a tendency to develop resistance in vitro. LrA demonstrated a synergistic or additive effect when combined with omeprazole (a proton pump inhibitor) against H. pylori. The combination of LrA and omeprazole showed promising anti-H. pylori potential, exhibiting notable in vivo efficacy comparable to standard triple therapy in mouse models infected with both drug-sensitive and drug-resistant H. pylori strains. Moreover, the narrow-spectrum antibacterial profile of LrA is reflected in its minimal effect on the diversity and composition of the mouse gut microbiota. The underlying mechanism of action of LrA against H. pylori involves the generation of bactericidal levels of reactive oxygen species, resulting in apoptosis-like cell death. These findings indicate that LrA is a promising lead compound targeting H. pylori without harming the commensal bacteria.

Epiberberine: a potential rumen microbial urease inhibitor to reduce ammonia release screened by targeting UreG

Rumen microbial urease inhibitors have been proposed for regulating nitrogen emission and improving nitrogen utilization efficiency in ruminant livestock industry. However, studies on plant-derived natural inhibitors of rumen microbial urease are limited. Urease accessory protein UreG, plays a crucial role in facilitating urease maturation, is a new target for design of urease inhibitor. The objective of this study was to select the potential effective inhibitor of rumen microbial urease from major protoberberine alkaloids in Rhizoma Coptidis by targeting UreG. Our results showed that berberine chloride and epiberberine exerted superior inhibition potential than other alkaloids based on GTPase activity study of UreG. Berberine chloride inhibition of UreG was mixed type, while inhibition kinetics type of epiberberine was uncompetitive. Furthermore, epiberberine was found to be more effective than berberine chloride in inhibiting the combination of nickel towards UreG and inducing changes in the second structure of UreG. Molecular modeling provided the rational structural basis for the higher inhibition potential of epiberberine, amino acid residues in G1 motif and G3 motif of UreG formed interactions with D ring of berberine chloride, while interacted with A ring and D ring of epiberberine. We further demonstrated the efficacy of epiberberine in the ruminal microbial fermentation with low ammonia release and urea degradation. In conclusion, our study clearly indicates that epiberberine is a promising candidate as a safe and effective inhibitor of rumen microbial urease and provides an optimal strategy and suitable feed additive for regulating nitrogen excretion in ruminants in the future. KEY POINTS: • Epiberberine is the most effective inhibitor of rumen urease from Rhizoma Coptidis. • Urease accessory protein UreG is an effective target for design of urease inhibitor. • Epiberberine may be used as natural feed additive to reducing NH3 release in ruminants.

Coptisine inhibits aggressive and proliferative actions of fibroblast like synoviocytes and exerts a therapeutic potential for rheumatoid arthritis

OBJECTIVE

Coptisine, a natural bioactive small molecular compound extracted from traditional Chinese herb Coptis chinensis, has been shown to exhibit anti-tumor effect. However, its contribution to autoimmune diseases such as rheumatoid arthritis (RA) is unknown. Here, we evaluate the effect of coptisine in controlling fibroblast-like synoviocytes (FLS)-mediated synovial proliferation and aggression in RA and further explore its underlying mechanism(s).

METHODS

FLS were separated from synovial tissues obtained from patients with RA. Protein expression was measured by Western blot or immunohistochemistry. Gene expression was detected by quantitative RT-PCR. The EdU incorporation was used to measure cell proliferation. Migration and invasion were determined by Boyden chamber assay. RNA sequencing analysis was used to seek for the target of coptisine. The in vivo effect of coptisine was evaluated in collagen-induced arthritis (CIA) model.

RESULTS

Treatment with coptisine reduced the proliferation, migration, and invasion, but not apoptosis of RA FLS. Mechanistically, we identified PSAT1, an enzyme that catalyzes serine/one-carbon/glycine biosynthesis, as a novel targeting gene of coptisine in RA FLS. PSAT1 expression was increased in FLS and synovial tissues from patients with RA compared to healthy control subjects. Coptisine treatment or PSAT1 knockdown reduced the TNF-α-induced phosphorylation of p38, ERK1/2, and JNK MAPK pathway. Interestingly, coptisine administration improved the severity of arthritis and reduced synovial PSAT1 expression in mice with CIA.

CONCLUSIONS

Our data demonstrate that coptisine treatment suppresses aggressive and proliferative actions of RA FLS by targeting PSAT1 and sequential inhibition of phosphorylated p38, ERK1/2, and JNK MAPK pathway. Our findings suggest that coptisine might control FLS-mediated rheumatoid synovial proliferation and aggression, and be a novel potential agent for RA treatment.

Helicobacter pylori infection in humans and phytotherapy, probiotics, and emerging therapeutic interventions: a review

The global prevalence of Helicobacter pylori (H. pylori) infection remains high, indicating a persistent presence of this pathogenic bacterium capable of infecting humans. This review summarizes the population demographics, transmission routes, as well as conventional and novel therapeutic approaches for H. pylori infection. The prevalence of H. pylori infection exceeds 30% in numerous countries worldwide and can be transmitted through interpersonal and zoonotic routes. Cytotoxin-related gene A (CagA) and vacuolar cytotoxin A (VacA) are the main virulence factors of H. pylori, contributing to its steep global infection rate. Preventative measures should be taken from people's living habits and dietary factors to reduce H. pylori infection. Phytotherapy, probiotics therapies and some emerging therapies have emerged as alternative treatments for H. pylori infection, addressing the issue of elevated antibiotic resistance rates. Plant extracts primarily target urease activity and adhesion activity to treat H. pylori, while probiotics prevent H. pylori infection through both immune and non-immune pathways. In the future, the primary research focus will be on combining multiple treatment methods to effectively eradicate H. pylori infection.

Epiberberine inhibits Helicobacter pylori and reduces host apoptosis and inflammatory damage by down-regulating urease expression

ETHNOPHARMACOLOGICAL RELEVANCE

With dramatically increasing antibiotic resistance in Helicobacter pylori (H. pylori), it is urgent to find alternative therapeutic agents. Rhizoma Coptidis is a traditional Chinese medicine for gastrointestinal diseases and shows excellent anti-H. pylori effect. Epiberberine (EPI), as one of the major alkaloids of Rhizoma Coptidis, has been reported to have urease-inhibiting activity, but its scavenging effect on H. pylori and the potential mechanism remain unclear.

AIM OF THE STUDY

To investigate the inhibitory effect of EPI on H. pylori and explore its multi-action on Helicobacter pylori urease (HPU).

MATERIALS AND METHODS

Using minimum inhibitory concentration (MIC) assay, minimum bactericidal concentration (MBC) assay, growth inhibition kinetics assay, bacterial resistance development, transmission electron microscope (TEM) assay, and animal experiments to investigate the inhibitory effect of EPI on H. pylori in vitro and in vivo. Using the Berthelot method, molecular docking and thermal displacement experiments to verify that EPI inhibits urease activity by interacting with HPU. Using transcriptome data, Real-Time PCR (RT-PCR) experiments to investigate the alterations in the expression of urease subunit ureB gene after EPI treatment. Using MTT cell viability assay, Hoechst 33342 staining method, JC-1 reagent detection method, western blot experiments, and Griess method to investigate the anti-apoptosis and anti-inflammation actions of EPI on gastric epithelial cells (GES-1) induced by HPU.

RESULTS

In vitro experiments proved that EPI has significant anti-H. pylori activity without drug resistance, induces H. pylori fragmentation and apoptosis. In vivo experiments showed that EPI has a certain clearance effect of H. pylori, and can reduce gastric inflammation caused by H. pylori infection. Transcriptome data, RT-PCR experiments, and other experiments demonstrate that EPI has a triple effect: (1) inhibiting the expression of HPU subunits ureB, (2) directly inhibiting urease activity by interacting with HPU, and (3) inhibiting HPU-induced apoptosis and inflammation in GES-1.

CONCLUSIONS

EPI is an excellent anti-H. pylori agent and reduces host apoptosis and inflammation by inhibiting the activity of urease and down-regulating the expression of ureB.

Identification of the therapeutic effect and molecular mechanism of Coptis chinensis Franch. and Magnolia officinalis var. biloba on chronic gastritis

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine (TCM) theory believes that clearing heat and promoting dampness is the main treatment method for chronic gastritis. Coptis chinensis Franch. has the effects of clearing heat, detoxifying, and anti-inflammatory; Magnolia officinalis var. biloba can be used to treat abdominal pain, cough, and asthma. Coptis chinensis Franch. and Magnolia officinalis var. biloba can regulate the balance of intestinal microbiota and inhibit inflammatory reactions.

AIM

This study will verify the therapeutic effect of Coptis chinensis Franch. and Magnolia officinalis var. biloba on chronic gastritis, and explore its mechanism through transcriptome sequencing.

METHODS

Firstly, a rat chronic gastritis model was established, and the anal temperature and body weight changes of the rats before and after modeling were observed. Next, H&E staining, TUNEL assay and ELISA assay were performed on rat gastric mucosal tissues. Subsequently, the key fractions of Coptis chinensis Franch. and Magnolia officinalis var. biloba were obtained by high performance liquid chromatography (HPLC), and a GES-1 cell inflammation model was constructed to select the optimal monomer. Finally, the mechanism of action of Coptis chinensis Franch. and Magnolia officinalis var. biloba was explored through RNA seq.

RESULTS

Compared with the control group, the rats in the administered group were in better condition, with higher anal temperature, reduced inflammatory response in gastric mucosal tissue and reduced apoptosis. The optimal fraction Coptisine was subsequently determined by HPLC and GES-1 cell model. RNA-seq analysis revealed that DEG was significantly enriched in ribosomes, NF-κB signaling pathway, etc. The key genes TPT1 and RPL37 were subsequently obtained.

CONCLUSIONS

This study verified the therapeutic effects of Coptis chinensis Franch. and Magnolia officinalis var. biloba on chronic gastritis by in vivo and in vitro experiments in rats, identified Coptisine as the optimal component, and obtained two potential target genes.

New trends in the practical use of isoquinoline alkaloids as potential drugs applicated in infectious and non-infectious diseases

In the last years, traditional natural products have been the center of attention for the scientific community and exploration of their therapeutic abilities is proceeding permanently. Isoquinoline alkaloids have always attracted scientific interest due to either their positive or negative effects on human organism. The present review describes research on isoquinoline alkaloids isolated from different plant species. Alkaloids are one of the most important classes of plant derived compounds among these isoquinoline alkaloids possess varied biological activities such as anticancer, antineurodegenerative diseases, antidiabetic, antiinflammatory, antimicrobial, and many others. The use of plants against different disorders is entrenched in traditional medicine around the globe. Recent progress in modern therapeutics has stimulated the use of natural products worldwide for various ailments and diseases. The review provides a collection of information on the capabilities of some isoquinoline alkaloids, its potential for the treatment of various diseases and is designed to be a guide for future research on different biologically active isoquinoline alkaloids and plant species containing them. The authors are aware that they were not able to cover the whole area of the topic related to biological activity of isoquinoline alkaloids. This review is intended to suggest directions for further research and can also help other researchers in future studies.

Coptisine, the Characteristic Constituent from Coptis chinensis, Exhibits Significant Therapeutic Potential in Treating Cancers, Metabolic and Inflammatory Diseases

Naturally derived alkaloids belong to a class of quite significant organic compounds. Coptisine, a benzyl tetrahydroisoquinoline alkaloid, is one of the major bioactive constituents in Coptis chinensis Franch., which is a famous traditional Chinese medicine. C. chinensis possesses many kinds of functions, including the ability to eliminate heat, expel dampness, purge fire, and remove noxious substances. In Asian countries, C. chinensis is traditionally employed to treat carbuncle and furuncle, diabetes, jaundice, stomach and intestinal disorders, red eyes, toothache, and skin disorders. Up to now, there has been plenty of research of coptisine with respect to its pharmacology. Nevertheless, a comprehensive review of coptisine-associated research is urgently needed. This paper was designed to summarize in detail the progress in the research of the pharmacology, pharmacokinetics, safety, and formulation of coptisine. The related studies included in this paper were retrieved from the following academic databases: The Web of Science, PubMed, Google scholar, Elsevier, and CNKI. The cutoff date was January 2023. Coptisine manifests various pharmacological actions, including anticancer, antimetabolic disease, anti-inflammatory disease, and antigastrointestinal disease effects, among others. Based on its pharmacokinetics, the primary metabolic site of coptisine is the liver. Coptisine is poorly absorbed in the gastrointestinal system, and most of it is expelled in the form of its prototype through feces. Regarding safety, coptisine displayed potential hepatotoxicity. Some novel formulations, including the [Formula: see text]-cyclodextrin-based inclusion complex and nanocarriers, could effectively enhance the bioavailability of coptisine. The traditional use of C. chinensis is closely connected with the pharmacological actions of coptisine. Although there are some disadvantages, including poor solubility, low bioavailability, and possible hepatotoxicity, coptisine is still a prospective naturally derived drug candidate, especially in the treatment of tumors as well as metabolic and inflammatory diseases. Further investigation of coptisine is necessary to facilitate the application of coptisine-based drugs in clinical practice.

Helicobacter pylori infection: a dynamic process from diagnosis to treatment

Helicobacter pylori, a gram-negative microaerophilic pathogen, causes several upper gastrointestinal diseases, such as chronic gastritis, peptic ulcer disease, and gastric cancer. For the diseases listed above, H. pylori has different pathogenic mechanisms, including colonization and virulence factor expression. It is essential to make accurate diagnoses and provide patients with effective treatment to achieve positive clinical outcomes. Detection of H. pylori can be accomplished invasively and noninvasively, with both having advantages and limitations. To enhance therapeutic outcomes, novel therapeutic regimens, as well as adjunctive therapies with probiotics and traditional Chinese medicine, have been attempted along with traditional empiric treatments, such as triple and bismuth quadruple therapies. An H. pylori infection, however, is difficult to eradicate during treatment owing to bacterial resistance, and there is no commonly available preventive vaccine. The purpose of this review is to provide an overview of our understanding of H. pylori infections and to highlight current treatment and diagnostic options.

Review of Phytochemical Potency as a Natural Anti-Helicobacter pylori and Neuroprotective Agent

Phytochemicals are plant secondary metabolites that show health benefits for humans due to their bioactivity. There is a huge variety of phytochemicals that have already been identified, and these compounds can act as antimicrobial and neuroprotection agents. Due to their anti-microbial activity and neuroprotection, several phytochemicals might have the potency to be used as natural therapeutic agents, especially for Helicobacter pylori infection and neurodegenerative disease, which have become a global health concern nowadays. According to previous research, there are some connections between H. pylori infection and neurodegenerative diseases, especially Alzheimer's disease. Hence, this comprehensive review examines different kinds of phytochemicals from natural sources as potential therapeutic agents to reduce H. pylori infection and improve neurodegenerative disease. An additional large-scale study is needed to establish the connection between H. pylori infection and neurodegenerative disease and how phytochemicals could improve this condition.

Efficacy and safety of triple therapy containing berberine, amoxicillin, and vonoprazan for Helicobacter pylori initial treatment: A randomized controlled trial

BACKGROUND

With the development of traditional Chinese medicine research, berberine has shown good efficacy and safety in the eradication of Helicobacter pylori (H. pylori). The present study aimed to evaluate the efficacy and safety of triple therapy containing berberine, amoxicillin, and vonoprazan for the initial treatment of H. pylori.

METHODS

This study was a single-center, open-label, parallel, randomized controlled clinical trial. Patients with H. pylori infection were randomly (1:1:1) assigned to receive berberine triple therapy (berberine 500 mg, amoxicillin 1000 mg, vonoprazan 20 mg, A group), vonoprazan quadruple therapy (vonoprazan 20 mg, amoxicillin 1000 mg, clarithromycin 500 mg, colloidal bismuth tartrate 220 mg, B group), or rabeprazole quadruple therapy (rabeprazole 10 mg, amoxicillin 1000 mg, clarithromycin 500 mg, colloidal bismuth tartrate 220 mg, C group). The drugs were taken twice daily for 14 days. The main outcome was the H. pylori eradication rate. The secondary outcomes were symptom improvement rate, patient compliance, and incidence of adverse events. Furthermore, factors affecting the eradication rate of H. pylori were further analyzed.

RESULTS

A total of 300 H. pylori-infected patients were included in this study, and 263 patients completed the study. An intention-to-treat (ITT) analysis showed that the eradication rates of H. pylori in berberine triple therapy, vonoprazan quadruple therapy, and rabeprazole quadruple therapy were 70.0% (70/100), 77.0% (77/100), and 69.0% (69/100), respectively. The per-protocol (PP) analysis showed that the eradication rates of H. pylori in these three groups were 81.4% (70/86), 86.5% (77/89), and 78.4% (69/88), respectively. Both ITT analysis and PP analysis showed that the H. pylori eradication rate did not significantly differ among the three groups (P >0.05). In addition, the symptom improvement rate, overall adverse reaction rate, and patient compliance were similar among the three groups (P >0.05).

CONCLUSIONS

The efficacy of berberine triple therapy for H. pylori initial treatment was comparable to that of vonoprazan quadruple therapy and rabeprazole quadruple therapy, and it was well tolerated. It could be used as one choice of H. pylori initial treatment.

Antibacterial activity mechanism of coptisine against Pasteurella multocida

Objective

Pasteurella multocida is a widespread zoonotic pathogen that causes severe damage to the poultry industry. This study focused on the antibacterial effects and mechanism of action of coptisine against P. multocida.

Methods

The minimum inhibitory concentration and half maximal inhibitory concentration of coptisine against P. multocida was measured. Additionally, the effect of coptisine on growth, cell wall, activity of respiratory enzymes, soluble protein content and DNA synthesis were also analyzed. Finally, the effect of coptisine on gene transcription was determined using RNA sequencing.

Results

We demonstrated that coptisine has a strong antibacterial effect against P. multocida, with a minimum inhibitory concentration of 0.125 mg/mL. Moreover, the measurement of the half maximal inhibitory concentration confirmed that coptisine was safe for the pathogen. The growth curve showed that coptisine inhibited bacterial growth. Measurement of alkaline phosphatase activity in the culture solution showed that coptisine affected cell wall permeability. Transmission electron microscopy revealed that coptisine chloride destroyed the cell structure. In addition, coptisine blocked the respiratory system, as measured by the levels of critical enzymes of the tricarboxylic acid cycle and glycolysis, succinate dehydrogenase and lactate dehydrogenase, respectively. Similarly, coptisine inhibited the synthesis of soluble proteins and genomic DNA. The KEGG pathway analysis of the differentially expressed genes showed that they were associated with cellular, respiratory, and amino acid metabolism, which were downregulated after coptisine treatment. Additionally, genes related to RNA degradation and the aminoacyl-tRNA pathway were upregulated.

Conclusion

In this study, we demonstrated that coptisine exerts an antibacterial effect on P. multocida. These findings suggest that coptisine has a multifaceted impact on various pathways, resulting in the inhibition of P. multocida. Thus, coptisine is a potential alternative to antibiotics for the treatment of P. multocida infections in a clinical setting.

Coptisine inhibits Helicobacter pylori and reduces the expression of CagA to alleviate host inflammation in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Helicobacter pylori (H. pylori) is a major pathogen colonized in the human stomach and is implicated in gastritis, peptic ulcer, and gastric carcinoma. Antibiotics are useful for eradicating H. pylori but failed for drug resistance, making it urgent to develop effective and safe drugs. Rhizoma Coptidis was reported as one of the most effective Chinese medicines to treat H. pylori-related gastrointestinal diseases, while the precise antimicrobial mechanism remains unclear. Thus, it is of great significance to study the antimicrobial ingredients and corresponding mechanisms of Rhizoma Coptidis.

AIM OF THE STUDY

To search for the most effective alkaloid against H. pylori in Rhizoma Coptidis and illustrate the probable mechanisms.

MATERIALS AND METHODS

Five main alkaloids in Rhizoma Coptidis were isolated. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were tested to determine the most effective one. Bacterial growth experiments, Annexin V-FITC/PI staining, TUNEL staining, and transmission electron microscopy (TEM) were performed to further study the anti-H. pylori activity of coptisine (Cop). The in vivo effect of Cop on H. pylori eradication rate and H. pylori-induced inflammation was investigated in mice. Transcriptomics was used to understand the underlying mechanism of eradicating H. pylori and reducing host inflammation. Western blot, RT-PCR, and ELISA experiments were utilized and confirmed that cagA was one of the targets of Cop.

RESULTS

According to the MIC and MBC, Cop was the most effective alkaloid against H. pylori, especially with no drug resistance developed. In vitro experiments showed that Cop inhibited H. pylori by inducing DNA fragmentation, phosphatidylserine exposure, and membrane damage. Cop (150 mg/kg/day) effectively eradicated H. pylori in mice and reduced the levels of IL-2 and IL-6 to relieve gastric inflammation. Transcriptomic analysis revealed that virulence factor cagA was one of the hub genes associated with the inflammation-improving effect of Cop. That is, Cop could decrease the expression of CagA and subsequently reduce the translocation of CagA to gastric epithelial cells, thereby improving the morphology of hummingbird-like phenotype induced by CagA and alleviating inflammation.

CONCLUSIONS

Cop is the most effective alkaloid in Rhizoma Coptidis and might act through multiple mechanisms for H. pylori eradication along with reducing the expression of CagA to alleviate inflammation.

Coptis, Pinellia, and Scutellaria as a promising new drug combination for treatment of Helicobacter pylori infection

BACKGROUND

Helicobacter pylori (H. pylori) is the most important infectious agent and plays an important role in the progression of chronic gastritis and the development of gastric cancer.

AIM

To identify efficient therapeutic agents or strategies that can treat H. pylori infection.

METHODS

We performed literature analysis, experimental validation, and network pharmacology. First, traditional Chinese medicine (TCM) prescriptions for the treatment of H. pylori infection were obtained from the China National Knowledge Infrastructure, China Biology Medicine, China Science and Technology Journal Database, and WanFang databases. In addition, we conducted a relevant search by Reference Citation Analysis (RCA) (https://www.referencecitationanalysis.com). Next, we used TCM Inheritance Support System V2.5 to identify core drug combinations in the TCM prescriptions. Then, an H. pylori-associated chronic mouse model of gastritis was established. The antibacterial properties and anti-inflammatory potential of the core drug combination were evaluated by the rapid urease test, modified Warthin-Starry silver staining, histopathological analysis, and enzyme linked immunosorbent assay. Finally, the active compounds, hub targets, and potential signaling pathways associated with the core drug combination were analyzed by network pharmacology.

RESULTS

The TCM treatment of H. pylori was mainly based on reinforcing the healthy Qi and eliminating pathogenic factors by simultaneously applying pungent dispersing, bitter descending, cold and warm drugs. The combination of Coptis, Pinellia, and Scutellaria (CPS) was identified as the core drug combination from 207 prescriptions and 168 herbs. This drug combination eradicated H. pylori, alleviated the gastric pathology induced by H. pylori infection, and reduced the expression levels of tumor necrosis factor-α (P = 0.024) and interleukin-1β (P = 0.001). Moreover, a total of 35 compounds and 2807 targets of CPS were identified using online databases. Nine key compounds (tenaxin I, neobaicalein, norwogonin, skullcapflavone II, baicalein, 5,8,2'-trihydroxy-7-methoxyflavone, acacetin, panicolin, and wogonin) and nine hub target proteins (EGFR, PTGS2, STAT3, MAPK3, MAPK8, HSP90AA1, MAPK1, MMP9, and MTOR) were further explored. Seventy-seven signaling pathways were correlated with H. pylori-induced inflammation and carcinogenesis.

CONCLUSION

In summary, we showed that CPS is the core drug combination for treating H. pylori infection. Animal experiments demonstrated that CPS has bacteriostatic properties and can reduce the release of inflammatory cytokines in the gastric mucosa. Network pharmacology predictions further revealed that CPS showed complex chemical compositions with multi-target and multi-pathway regulatory mechanisms. Although the results derived from network pharmacology are not necessarily comprehensive, they still expand our understanding of CPS for treating H. pylori infection.

Efficacy and safety of triple therapy containing berberine hydrochloride, amoxicillin, and rabeprazole in the eradication of Helicobacter pylori

OBJECTIVE

To estimate the effectiveness and safety of triple therapy containing berberine, amoxicillin, and rabeprazole in the eradication of Helicobacter pylori (H. pylori).

METHODS

This prospective, randomized controlled, open-label, noninferiority trial included treatment-naive patients with H. pylori infection who were randomly allocated at a ratio of 1:1 into the berberine triple therapy group (berberine hydrochloride 300 mg thrice daily, amoxicillin 1 g twice daily, and rabeprazole 10 mg twice daily) or standard bismuth-containing quadruple therapy group (amoxicillin 1 g twice daily, rabeprazole 10 mg twice daily, clarithromycin 500 mg twice daily, and bismuth tartrate 200 mg twice daily) for 14 days. Negative ¹³ C/¹⁴ C-urea breath test at 4 weeks after completion of the therapy was regarded as successful eradication.

RESULTS

Altogether 262 and 262 patients received berberine triple therapy and bismuth-containing quadruple therapy, respectively. Both intention-to-treat (79.8% vs 80.9%, P = 0.742) and per-protocol analyses (83.6% and 85.1%, P = 0.636) showed comparable eradication rate between the two groups, indicating a noninferior eradication rate (the lower limit of the 95% confidence interval over -10% [-7.9% and -7.87%, respectively]). Adverse events more commonly occurred in the bismuth-containing quadruple-therapy group (8.8% vs 16.0%, P = 0.012), while patient compliance and symptom improvement of the two regimens were comparable.

CONCLUSION

Triple therapy containing berberine, amoxicillin and rabeprazole is noninferior to bismuth-containing quadruple therapy in the initial treatment for H. pylori eradication.

Sanguinarine, a major alkaloid from Zanthoxylum nitidum (Roxb.) DC., inhibits urease of Helicobacter pylori and jack bean: Susceptibility and mechanism

ETHNOPHARMACOLOGICAL RELEVANCE

Zanthoxylum nitidum (Roxb.) DC. (Z. nitidum) is a traditional Chinese medicine and mainly adopted to treat gastric ulcer, gastritis and stomach cancer. Sanguinarine (SNG), a natural alkaloid isolated from Z. nitidum, possesses significant anti-Helicobacter pylori and gastric protection effects. However, the underlying mechanism is sparsely elucidated.

AIM OF THIS STUDY

The present study aims to explore the inhibition effect, kinetics and potential mechanism of SNG against H. pylori urease (HPU) and jack bean urease (JBU).

MATERIALS AND METHODS

The improved spectrophotometric berthelot method was applied to estimate the inhibitory effect of SNG against HPU and JBU. The Lineweaver-Burk plots were adopted for investigating the inhibitory pattern in enzymatic kinetics. Sulfydryl-containing compounds and competitive active-site Ni²⁺ binding depressors were used for mechanism research.

RESULTS

SNG remarkably suppressed the activities of HPU and JBU in concentration-and time-dependent mode with IC₅₀ of 0.48 ± 0.14 mM and 0.11 ± 0.02 mM, respectively, in comparison with urease retardant acetohydroxamic acid (0.06 ± 0.01 mM for HPU and 0.03 ± 0.00 mM for JBU, respectively). Kinetic analysis demonstrated that the inhibition of SNG against HPU and JBU were separately characterized by slow-binding, mixed-type and slow-binding, non-competitive type. Addition of sulfydryl-containing reagents (dithiothreitol, glutathione and L-cysteine) and competitive Ni²⁺ binding restrainers (boric acid and sodium fluoride) significantly abrogated the urease inhibitory effect of SNG, suggesting the significant role of the thiols and Ni²⁺ for the urease inhibition by SNG. By contrast, interaction with thiol groups possibly contributed to the repression of SNG on JBU. Furthermore, the urease suppression was proved to be partially reversible since the SNG-blocked enzyme could be partly reactivated by glutathione.

CONCLUSION

SNG could observably inhibit H. pylori urease targeting the thiols and Ni²⁺, which indicated that SNG was a new urease suppressant with great promise. The present research also provided scientific evidence for the application of SNG and Z. nitidum treating H. pylori-associated gastrointestinal diseases.

Bioactive components of Banxia Xiexin Decoction for the treatment of gastrointestinal diseases based on flavor-oriented analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Banxia Xiexin Decoction (BXD) was first recorded in a Chinese medical classic, Treatise on Febrile Diseases and Miscellaneous Diseases, which was written in the Eastern Han dynasty of China. This ancient prescription consists of seven kinds of Chinese herbal medicine, namely, Pinellia ternata, Rhizoma Coptidis, Radix scutellariae, Rhizoma Zingiberis, Ginseng, Jujube, and Radix Glycyrrhizaepreparata. In clinic practice, its original application in China mainly has focused on the treatment of chronic gastritis for several hundred years. BXD is also effective in treating other gastrointestinal diseases (GIDs) in modern medical application. Despite available literature support and clinical experience, the treatment mechanisms or their relationships with the bioactive compounds in BXD responsible for its pharmacological actions, still need further explorations in more diversified channels. According to the analysis based on the five-flavor theory of TCM, BXD is traditionally viewed as the most representative prescription for pungent-dispersion, bitter-purgation and sweet-tonification. Consequently, based on the flavor-oriented analysis, the compositive herbs in BXD can be divided into three flavor groups, namely, the pungent, bitter, and sweet groups, each of which has specific active ingredients that are possibly relevant to GID treatment.

AIM OF THE REVIEW

This paper summarized recent literatures on BXD and its bioactive components used in GID treatment, and provided the pharmacological or chemical basis for the further exploration of the ancient prescription and the relative components.

METHOD

ology: Relevant literature was collected from various electronic databases such as Pubmed, Web of Science, and China National Knowledge Infrastructure (CNKI). Citations were based on peer-reviewed articles published in English or Chinese during the last decade.

RESULTS

Multiple components were found in the pungent, bitter, and sweet groups in BXD. The corresponding bioactive components include gingerol, shogaol, stigmasterol, and β-sitosterol in the pungent group; berberine, palmatine, coptisine, baicalein, and baicalin in the bitter group; and ginsenosides, polysaccharides, liquiritin, and glycyrrhetinic acid in the sweet group. These components have been found directly or indirectly responsible for the remarkable effects of BXD on GID.

CONCLUSION

This review provided some valuable reference to further clarify BXD treatment for GID and their possible material basis, based on the perspective of the flavor-oriented analysis.

Paper mill sludge-based carbon quantum dots as a specifically ratiometric fluorescent probe for the sensitive and selective detection of coptisine

Coptisine (COP), one of the bioactive components in Rhizoma Coptidis, has many pharmacological effects. Meanwhile, the determination of COP is essential in pharmacological and clinical applications. Herein, we prepared carbon quantum dots (CQDs) by one-step oil-thermal method using paper mill sludge (PMS) as precursor, and developed a ratiometric fluorescence method for the determination of COP. The structural and optical properties of PMS-CQDs were evaluated through HRTEM, FT-IR, XPS, XRD, UV-vis, fluorescence, zeta potential and fluorescence lifetime experiments. Fluorescence intensity ratio at 550 nm and 425 nm (I₅₅₀ /I₄₂₅ ) was recorded as an index for quantitative detection of COP. The detection concentration of COP ranges from 0.1 to 50 μM in good linear correlation (R² = 0.9974) with a limit of detection of 0.028 μM (3σ/k). The quenching mechanism was deduced to be inner filter effect and static quenching. The ratiometric fluorescent probe showed impressive selectivity and sensitivity towards COP, and was successfully applied to the detection of COP in human urine with expected recoveries (95.22-111.00%) and relative standard deviation (0.46-2.95%), indicating that our developed method has a great application prospect in actual sample detection.

Coptisine: A natural plant inhibitor of ruminal bacterial urease screened by molecular docking

Inhibition of ruminal bacterial urease activity could slow down the decomposition of urea to ammonia, which would lead to a decrease in urea synthesis in the liver and urea-N emission in the urine. In order to find a rumen bacterial urease specific inhibitor that is environmentally friendly, we used the homology model of rumen bacterial urease as the target to screen natural compounds from plants by molecular docking. The screening results showed that coptisine had the most potential to inhibit the activity of rumen bacterial urease with an IC₅₀ of 2.45 μM, which was superior to the traditional inhibitor acetohydroxamic acid. The enzyme kinetics results indicated coptisine was mixed type inhibitor of rumen bacterial urease with a K_i value of 0.68 μM. Coptisine significantly decreased the release of NH₃ and decomposition of urea and improved microbial fermentation in a rumen fermentation system in vitro. Thiol-containing compounds or boric acid significantly decreased the inhibitory capacity of coptisine toward rumen bacterial urease, which indicated that coptisine could interact with both the urease active center Ni and amino acid residues possessing sulfhydryl groups in the flap area. The molecular docking results showed that coptisine acted as the metal acceptor for one nickel ion in the active site, and formed hydrogen bonds with the amino acid residues His320 and His362, which were located in the active site and flap region, respectively. These findings emphasized the potential role of coptisine in reducing nitrogen emissions that originate from ruminants by regulating rumen bacterial urease activity.

Inactivation of Jack Bean Urease by Nitidine Chloride from Zanthoxylum nitidum: Elucidation of Inhibitory Efficacy, Kinetics and Mechanism

Urease is a metalloenzyme that catalyzes the hydrolysis of urea into ammonia and carbon dioxide, which has a negative impact on human health and agriculture. In this study, the inactivation of jack bean urease by nitidine chloride (NC) was investigated to elucidate the inhibitory effect, kinetics, and underlying mechanism of action. The results showed that NC acted as a concentration- and time-dependent inhibitor with an IC₅₀ value of 33.2 ± 4.8 μM and exhibited a similar inhibitory effect to acetohydroxamic acid (IC₅₀ = 31.7 ± 5.8 μM). Further kinetic analysis demonstrated that NC was a slow-binding and non-competitive inhibitor for urease. Thiol-blocking reagents (dithiothreitol, glutathione, and l-cysteine) significantly retarded urease inactivation, while Ni²⁺ competitive inhibitors (boric acid and sodium fluoride) synergetically suppressed urease with NC, suggesting that the active site sulfhydryl groups were possibly obligatory for NC blocking urease. Molecular docking simulation further argued its inhibition mechanism. Additionally, NC-induced deactivation of urease was verified to be reversible since the inactivated enzyme could be reactivated by glutathione. Taking together, NC was a non-competitive inhibitor targeting the thiol group at the active site of urease with characteristics of concentration dependence, reversibility, and slow binding, serving as a promising novel urease suppressant.

Natural-derived alkaloids exhibit great potential in the treatment of ulcerative colitis

Ulcerative colitis (UC) is a chronic nonspecific inflammatory disease of colon and rectum with unknown etiology, and the lesions are mainly confined to the mucosa and submucosa of large intestine. The main clinical features of UC include diarrhea, abdominal pain, bloody purulent stool and tenesmus, which seriously affect patients' quality of life. Most of UC patients would receive drug therapy with the exception of surgery for some severe cases. However, current drugs for the treatment of UC have certain limitations including difficulty of radical treatment, adverse reactions and drug resistance after long-term use and exorbitant price of some drugs. The research and development of new drugs for the treatment of UC is urgent, and natural alkaloids are an important source. This research paid close attention to the progress of natural alkaloids from diverse medicinal plants for treating UC in the last twenty years. The potential mechanisms for the natural alkaloids in the treatment of UC was closely related to its modulation of oxidative stress, immune response, intestinal flora and improvement of the gut barrier function. Remarkable effectiveness and safety of natural-derived alkaloids make them potential candidates of UC therapy.

A review: antimicrobial properties of several medicinal plants widely used in Traditional Chinese Medicine

Due to the dramatic increase in the use of antibiotics and growing health threat of bacterial resistance to many commonly used antibiotics, many studies have been directed at developing new and effective antibacterial compounds, among which many new, natural, and effective antibacterial compounds discovered from medicinal plants have drawn great interest and raised new hope for treating the challenges of antibiotic resistance. This review aimed to summarize the most important and widely used medicinal plants that were reported to have antibacterial activities. A general literature search from 2010 to 2020 was conducted using different databases, including Science Direct, Web of Science, and PubMed. According to the literature, three medicinal plants with outstanding antibacterial activities, Taraxacum officinale, Coptis Rhizome, and Scutellaria baicalensis, were screened and reviewed by prioritization. The extraction methods, antibacterial activities of different parts of plants or the plant-derived compounds, spectra of antibacterial activities, and toxicity were described, respectively. However, the antibacterial activities of the extracts or pure compounds as reported in the reviewed literature were mostly based on in vitro assays, and moreover, the deeper antibacterial mechanisms have not been elucidated clearly. Therefore, further studies are required in the fields of purification and identification of the antibacterial compounds, its mechanisms of action, and synergistic effects in combination with other antibacterial drugs, which may be helpful in the development of new antibacterial drugs.

Chelerythrine Chloride: A Potential Rumen Microbial Urease Inhibitor Screened by Targeting UreG

Inhibition of ruminal microbial urease is of particular interest due to its crucial role in regulating urea-N utilization efficiency and nitrogen pollution in the livestock industry. Acetohydroxamic acid (AHA) is currently the only commercially available urease inhibitor, but it has adverse side effects. The urease accessory protein UreG, which facilitates the functional incorporation of the urease nickel metallocentre, has been proposed in developing urease inhibitor through disrupting urease maturation. The objective of this study was to screen natural compounds as potential urease inhibitors by targeting UreG in a predominant ruminal microbial urease. In silico screening and in vitro tests for potential inhibitors were performed using molecular docking and an assay for the GTPase activity of UreG. Chelerythrine chloride was selected as a potential urease inhibitor of UreG with an inhibition concentration IC₅₀ value of 18.13 μM. It exhibited mixed inhibition, with the K_i value being 26.28 μM. We further explored its inhibition mechanism using isothermal titration calorimetry (ITC) and circular dichroism (CD) spectroscopy, and we found that chelerythrine chloride inhibited the binding of nickel to UreG and induced changes in the secondary structure, especially the α-helix and β-sheet of UreG. Chelerythrine chloride formed a pi-anion interaction with the Asp41 residue of UreG, which is an important residue in initiating the conformational changes of UreG. In conclusion, chelerythrine chloride exhibited a potential inhibitory effect on urease, which provided new evidence for strategies to develop novel urease inhibitors targeting UreG to reduce nitrogen excretion from ruminants.

A review on the structures and biological activities of anti-Helicobacter pylori agents

Helicobacter pylori is one of the main causal risk factor in the generation of chronic gastritis, gastroduodenal ulcers and gastric carcinoma. Thus, the eradication of H. pylori infection is an important way for preventing and managing the gastric diseases. Multiple-therapy with several antibacterial agents is used for the eradication of H. pylori infections; however the increase of resistance to H. pylori strains has resulted in unsatisfactory eradication and unsuccessful treatment. Furthermore, the combination therapy with high dosing leads to the disruption of intestinal microbial flora and undesired side effects. Therefore, the search for new therapeutic agents with high selectivity against H. pylori is a field of current interest. In recent years, diverse compounds originating from natural sources or synthetic drug design programs were evaluated and tried to optimize for applying against H. pylori. In this review, we have described various classes of anti-H. pylori compounds, their structure-activity relationship studies, and mechanism of actions, which could be useful for the development of new drugs for the treatment of H. pylori infections.

Coptisine ameliorates DSS-induced ulcerative colitis via improving intestinal barrier dysfunction and suppressing inflammatory response

Ulcerative colitis (UC), as an autoimmune disease, has been troubling human health for many years. Up to now, the available treatments remain unsatisfactory. Rhizoma Coptidis has been widely applied to treat gastrointestinal diseases in China for a long time, and coptisine (COP) is identified as one of its major active components. This study aimed to evaluate the bioactivity of COP on dextran sulfate sodium (DSS)-induced mice colitis and clarify the potential mechanism of action. The results revealed that COP treatment markedly alleviated DSS-induced clinical symptoms by relieving body weight loss and the disease activity index (DAI) score. Specifically, the colon length in the COP (50 and 100 mg/kg) groups were obviously longer than that in the DSS group (7.21 ± 0.34, 8.59 ± 0.45 cm vs. 6.71 ± 0.59 cm, P < 0.01). HE staining analysis revealed that COP treatment significantly protected the integrity of intestinal barrier and alleviated inflammatory cells infiltration. Western blot assay confirmed that COP notably improved the intestinal epithelial barrier function by enhancing the expressions of colonic tight junction proteins and inhibited the expressions of apoptosis-related proteins. In addition, COP treatment remarkably suppressed the levels of colonic myeloperoxidase (MPO), adhesion molecules and pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1β, IL-6 and IL-17), while enhanced IL-10 and TGF-β. The mechanism anti-inflammatory of COP might be related to inhibiting the phosphorylation of IκBα, and the translocation of NF-κB p65 from cytoplasm to nucleus. In summary, the study indicated that COP ameliorated DSS-induced colitis, at least partly through maintaining the integrity of intestinal epithelial barrier, inhibiting apoptosis and inflammatory response.

Oxyberberine, an absorbed metabolite of berberine, possess superior hypoglycemic effect via regulating the PI3K/Akt and Nrf2 signaling pathways

Berberine (BBR) is a promising anti-diabetic isoquinoline alkaloid from Rhizoma coptidis, while its bioavailability was extremely low. Here, the existing form and pharmacokinetics of BBR were comparatively characterized in conventional and antibiotic-induced pseudo germ-free (PGF) rats. Furthermore, we comparatively investigated the antidiabetic effect and potential mechanism of BBR and its intestinal oxidative metabolite oxyberberine (OBB) in STZ-induced diabetic rats. Results showed that BBR and OBB existed mainly as protein-bound form in blood, while protein-bound OBB was significantly depleted in PGF rats. Treatment with OBB and BBR effectively decreased clinical symptoms of diabetic rats, reduced blood glucose level, ameliorated the pancreatic damage, and mitigated oxidative stress and inflammatory markers. However, the anti-diabetes effect of BBR was obviously compromised by antibiotics. In addition, OBB exerted superior anti-diabetes effect to BBR of the same dose, significantly up-regulated the mRNA expression of Nrf2 signaling pathway and substantially promoted the pancreatic levels of PI3K/Akt signaling pathway. In conclusion, BBR and its absorbed oxidative metabolite OBB were mainly presented and transported in the protein-bound form in vivo. The gut microbiota may play an important role in the anti-diabetes effect of BBR through transforming itself into the superior hypoglycemic metabolite OBB. OBB possessed favorable hypoglycemic and pancreatic β-cells protective effects, which may stand a huge potential to be further developed into a promising anti-diabetes candidate.

Anti-microbial and anti-inflammatory effects of Cheonwangbosim-dan against Helicobacter pylori-induced gastritis

Background

There are various Helicobacter species colonizing the stomachs of animals. Although Helicobacter species usually cause asymptomatic infection in the hosts, clinical signs can occur due to gastritis associated with Helicobacter in animals. Among them, Helicobacter pylori is strongly associated with chronic gastritis, gastric ulcers, and gastric cancers. As the standard therapies used to treat H. pylori have proven insufficient, alternative options are needed to prevent and eradicate the diseases associated with this bacterium. Cheonwangbosim-dan (CBD), a traditional herbal formula that is popular in East Asia, has been commonly used for arterial or auricular flutter, neurosis, insomnia, and cardiac malfunction-induced disease.

Objectives

The present study investigated the antimicrobial effect of CBD on H. pylori-infected human gastric carcinoma AGS cells and model mice.

Methods

AGS cells were infected with H. pylori and treated with a variety of concentrations of CBD or antibiotics. Mice were given 3 oral inoculations with H. pylori and then dosed with CBD (100 or 500 mg/kg) for 4 weeks or with standard antibiotics for 1 week. One week after the last treatment, gastric samples were collected and examined by histopathological analysis, real-time quantitative polymerase chain reaction, and immunoblotting.

Results

Our results showed that CBD treatment of AGS cells significantly reduced the H. pylori-induced elevations of interleukin-8, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). In the animal model, CBD treatment inhibited the colonization of H. pylori and the levels of malondialdehyde, inflammation, proinflammatory cytokines, iNOS, and COX-2 in gastric tissues. CBD also decreased the phosphorylation levels of p38 mitogen-activated protein kinase family.

Conclusions

This study suggests that CBD might be a prospective candidate for treating H. pylori-induced gastric injury.

UPLC-Q-TOF/MS-Based Serum and Urine Metabonomics Study on the Ameliorative Effects of Palmatine on Helicobacter pylori-Induced Chronic Atrophic Gastritis

OBJECTIVE

The main objective of this study was to investigate the ameliorative effects of Palmatine (Pal) on Helicobacter pylori (H. pylori) induced chronic atrophic gastritis (CAG).

METHOD

Body function, serum biochemical indicators and histopathology were used to evaluate the pharmacodynamics of Pal on CAG rats. The target genes expression levels were verified and assessed by RT-PCR and immunohistochemistry (IHC). Moreover, UPLC-Q-TOF/MS analysis based on urine and serum was performed to identify the potential metabolites in the pathological process of CAG induced by H. pylori. Metabolic pathway analysis was performed to elucidate the metabolic network associated with Pal treatment of CAG.

RESULTS

Pal (10, 20, 40 mg/kg/day) significantly restored the body function of CAG rats, reduced the serum biochemical indicators, and maintained the integrity of the gastric mucosal epithelial barrier while alleviated gastric histological damage. Metabolomics analysis shows that the therapeutic effect of Pal on CAG involves 10 metabolites and 10 metabolic pathways, of which the Taurine and hypotaurine metabolism, Glycerophospholipid metabolism and Pentose and glucuronate interconversions are closely related to the gastrointestinal protection of Pal, and these metabolic pathways crosstalk with each other due to the internet hub of citric acid cycle.

CONCLUSIONS

Metabolomics was used for the first time to identify potential biomarkers of CAG and to illuminate the therapeutic mechanism of Pal on CAG induced by H. pylori. The results provided a new insight for further research on CAG treatment.

Insight into the inhibitory effects of Zanthoxylum nitidum against Helicobacter pylori urease and jack bean urease: Kinetics and mechanism

ETHNOPHARMACOLOGICAL RELEVANCE

Zanthoxylum nitidum (Roxb.) DC. is a traditional Chinese medicine characterised by anti-inflammatory and anti-Helicobacter pylori, which is widely used to treat H. pylori-induced gastric disease in China. However, the underlying mechanism related to its anti-H. pylori activity remains unclear. Urease plays a crucial role in the colonisation and survival of H. pylori.

AIM OF THE STUDY

The root aqueous extract of Z. nitidum against H. pylori urease (HPU) and jack bean urease (JBU) was investigated to illuminate the inhibitory potency, kinetics and potential mechanism.

MATERIALS AND METHODS

Z. nitidum components were determined by UPLC. The enzyme inhibitory effects of Z. nitidum were examined using modified spectrophotometric Berthelot (phenol-hypochlorite) method. Urease inhibition kinetics were determined by Lineweaver-Burk plots. Sulfhydryl group reagents and Ni²⁺-binding inhibitors were used in the mechanism study. Moreover, the molecular docking technique was used to investigate the binding conformations of the main compounds of Z. nitidum on Urease.

RESULTS

According to UPLC results, the major components of Z. nitidum were magnoflorine, sanguinarine, nitidine chloride, chelerythrine, skimmianine and L-Sesamin. Z. nitidum has higher enzyme inhibitory activity on HPU (IC₅₀ = 1.29 ± 0.10 mg/mL) than on JBU (IC₅₀ = 2.04 ± 0.27 mg/mL). Enzyme inhibitory kinetic analysis revealed that the type of Z. nitidum inhibition against HPU was a slow-binding and mixed-type, whereas a slow-binding and non-competitive type inhibited JBU. Further mechanism study indicated that the active site of sulfhydryl group might be the target of inhibition by Z. nitidum. The molecular docking study indicated that the above six main components of Z. nitidum exhibited stronger affinity to HPU than to JBU through interacting with the key amino acid residues located on the mobile flap or interacting with the active site Ni²⁺. Results indicated that these components are potential active ingredients directed against urease.

CONCLUSIONS

Z. nitidum inactivated urease in a concentration-dependent manner through slow-binding inhibition and binding to the urease active site sulfhydryl group. Our investigation might provide experimental evidence for the traditional application of Z. nitidum in the treatment of H. pylori-associated gastric disorders.

Coptisine from Coptis chinensis exerts diverse beneficial properties: A concise review

Coptisine is a natural small-molecular compound extracted from Coptis chinensis (CC) with a history of using for thousands of years. This work aimed at summarizing coptisine's activity and providing advice for its clinical use. We analysed the online papers in the database of SciFinder, Web of Science, PubMed, Google scholar and CNKI by setting keywords as 'coptisine' in combination of 'each pivotal pathway target'. Based on the existing literatures, we find (a) coptisine exerted potential to be an anti-cancer, anti-inflammatory, CAD ameliorating or anti-bacterial drug through regulating the signalling transduction of pathways such as NF-κB, MAPK, PI3K/Akt, NLRP3 inflammasome, RANKL/RANK and Beclin 1/Sirt1. However, we also (b) observe that the plasma concentration of coptisine demonstrates obvious non-liner relationship with dosage, and even the highest dosage used in animal study actually cannot reach the minimum concentration level used in cell experiments owing to the poor absorption and low availability of coptisine. We conclude (a) further investigations can focus on coptisine's effect on caspase-1-involved inflammasome assembling and pyroptosis activation, as well as autophagy. (b) Under circumstance of promoting coptisine availability by pursuing nano- or microrods strategies or applying salt-forming process to coptisine, can it be introduced to clinical trial.

Design, synthesis and biological evaluation of Helicobacter pylori inosine 5'-monophosphate dehydrogenase (HpIMPDH) inhibitors. Further optimization of selectivity towards HpIMPDH over human IMPDH2

Inosine 5'-monophosphate dehydrogenase (IMPDH, EC 1.1.1.205) catalyzes a crucial step in guanine nucleotide biosynthesis, thereby governing cell proliferation. In contrast to mammalian IMPDHs, microbial IMPDHs are relatively less explored as potential targets for antimicrobial drug discovery. In continuation with our previous work, here we report the discovery of moderately potent and highly selective Helicobacter pylori IMPDH (HpIMPDH) inhibitors. The present study is mainly focused around our previously identified, modestly potent and relatively nonselective (for HpIMPDH over human IMPDH2) hit molecule IX (16i). In an attempt to optimize the selectivity for the bacterial enzyme, we screened a set of 48 redesigned new chemical entities (NCEs) belonging to 5-aminoisobenzofuran-1(3H)-one series for their in vitro HpIMPDH and human IMPDH2 inhibition. A total of 12 compounds (hits) demonstrated ≥70% HpIMPDH inhibition at 10 μM concentration; none of the hits were active against hIMPDH2. Compound 24 was found to be the most potent and selective molecule (HpIMPDH IC50 = 2.21 µM) in the series. The study reaffirmed the utility of 5-aminoisobenzofuran-1(3H)-one as a promising scaffold with great potential for further development of potent and selective HpIMPDH inhibitors.