Chrysin Modulates Genes Related to Inflammation, Tissue Remodeling, and Cell Proliferation in the Gastric Ulcer Healing

Targeting TRPV1 signaling: Galangin improves ethanol-induced gastric mucosal injury

ETHNOPHARMACOLOGICAL RELEVANCE

Galangin, a bioactive compound extracted from Alpinia officinarum Hance (Zingiberaceae), a plant with significant ethnopharmacological importance, has been used for thousands of years as a spice, condiment, and medicinal agent for various conditions, including gastrointestinal disorders. Although there is evidence suggesting its potential to improve gastric ulcers, the molecular mechanisms underlying its anti-ulcer properties are not fully understood.

OBJECTIVE

of the Study: This study aimed to investigate the effects of galangin on ethanol-induced acute gastric mucosal injury (AGMI) in mice and elucidate its molecular mechanisms.

MATERIALS AND METHODS

Sixty BALB/c mice were randomly assigned into two main groups: a normal control group (n = 10) and an ethanol-induced group (n = 50). After establishing the AGMI model in mice using a combination of 40% ethanol and anhydrous ethanol, the ethanol-induced group was further subdivided into five subgroups (n = 10): an omeprazole control group (20 mg/kg), an untreated ethanol group, and three treatment groups receiving high-dose (50 mg/kg) or low-dose (25 mg/kg) galangin or capsazepine (CPZ, 2 mg/kg). The protective effects of galangin were evaluated through mucosal injury indices, hematoxylin and eosin staining, and quantification of inflammatory markers (IL-1β, IL-6, IL-8, and TNF-α). Oxidative stress levels and matrix metalloproteinase activity were measured using specific assay kits. Molecular docking was conducted to assess the binding affinity of galangin to key proteins within the transient receptor potential vanilloid 1 (TRPV1) pathway. Real-time fluorescence quantitative PCR (qPCR) was used to determine mRNA expression levels of TRPV1, calmodulin (CaM), substance P (SP), and CGRP in gastric tissues. Protein expression levels of TRPV1, nerve growth factor (NGF), tropomyosin receptor kinase A (TRKA), transforming growth factor beta (TGF-β), cyclooxygenase-2 (COX-2), and nuclear factor kappa B (NF-κB) were assessed through Western blot analysis. In cellular experiments, Culture of Human Gastric Epithelial Cells (GES-1) were treated with various concentrations of galangin after 7% ethanol induction. Cell proliferation, apoptosis, and migration were evaluated using Hoechst 33258 staining and transwell migration assays. TRPV1 protein expression was detected using immunofluorescence, and the expression levels of Bcl-2, BCL2-Associated X (BAX), and Caspase-3 were quantified by qPCR. Additionally, specific probe kits were used to measure intracellular calcium ions (Ca2+) and mitochondrial membrane potential.

RESULTS

The findings indicate that galangin significantly improved mucosal pathology by reducing ulcer indices and inflammatory levels, while enhancing superoxide dismutase (SOD) activity and decreasing malondialdehyde (MDA) concentration. Galangin also reduced matrix metalloproteinase-2 (MMP-2), m metalloproteinase-9 (MMP-9) levels, promoting mucosal repair. At the cellular level, galangin decreased intracellular calcium ion concentration and mitigated the decline in mitochondrial membrane potential, enhance the restoration of mucosal cells, increased migration and proliferation, and reduced apoptosis. Molecularly, galangin demonstrated favorable binding to TRPV1, NGF, TRKA, TGF-β, COX-2, and NF-κB, and reversed the elevated expression of these proteins. Additionally, galangin downregulated the mRNA expression of TRPV1, CaM, SP, CGRP, BAX, and Caspase-3 in gastric tissues/cells, while upregulating Bcl-2 mRNA expression.

CONCLUSION

Galangin mitigates AGMI by inhibiting the overactivation of the TRPV1 pathway, thereby blocking aberrant signal transduction. This study suggests that galangin has therapeutic potential against ethanol-induced AGMI and may be a viable alternative for the treatment of alcohol-induced gastric mucosal injuries.

Aibika Flower Flavonoid Extract Exhibits Antiulcer Activity in a Murine Model of Ethanol-Induced Acute Gastric Injury

Aibika (Abelmoschus manihot (L.) Medic) is a garden vegetable whose flower has been shown to have various bioactivities. This study investigated the protective effect of aibika flower flavonoid extract (AFF) on ethanol-induced gastric injury in mice. The experimental results showed that pre-feeding 125 and 250 mg AFF/kg BW for 1 week significantly reduced the gastric injury area in the negative control group from 19.2% to 6.7% and 0.6%, respectively. The results of the pathological sections staining also showed that AFF had a protective ability against alcohol-induced injury of gastric tissue and liver tissue. When the mice were exposed to high concentrations of ethanol, AFF pretreatment significantly upregulated the expression of antioxidant enzymes. The pretreatment also promoted the production of the intracellular antioxidant, reduced glutathione, in both gastric tissue and serum. On the contrary, AFF delayed the lipid peroxidation process, which, in turn, reduced the damage to the gastric mucosa. When acute inflammation was induced by ethanol stimulation, AFF significantly downregulated the proinflammatory cytokines and mediators such as TNF-α, IL-1β, IL-6, NF-κB, COX-2, and iNOS. Furthermore, AFF pretreatment greatly promoted the production of healing factors, such as matrix metalloproteinase (MMP)-2, MMP-7, and MMP-9, in the gastric tissue. In addition, AFF significantly reduced gastric cell apoptosis induced by ethanol stimulation. These results demonstrate that AFF has a good protective effect on alcohol-induced gastric ulcer and has the potential to be used in gastrointestinal health care.

Neuropeptide W facilitates chronic gastric ulcer healing by the regulation of cyclooxygenase and NF-κB signaling pathways

AIMS

Putative beneficial effects of neuropeptide W (NPW) in the early phase of gastric ulcer healing process and the involvement of cyclooxygenase (COX) enzymes were investigated in an acetic acid-induced gastric ulcer model.

MAIN METHODS

In anesthetized male Sprague-Dawley rats, acetic acid was applied surgically on the serosa and then a COX-inhibitor (COX-2-selective NS-398, COX-1-selective ketorolac, or non-selective indomethacin; 2 mg/kg/day, 3 mg/kg/day or 5 mg/kg/day; respectively) or saline was injected intraperitoneally. One h after ulcer induction, omeprazole (20 mg/kg/day), NPW (0.1 μg/kg/day) or saline was intraperitoneally administered. Injections of NPW, COX-inhibitors, omeprazole or saline were continued for the following 2 days until rats were decapitated at the end of the third day.

KEY FINDINGS

NPW treatment depressed gastric prostaglandin (PG) I2 level, but not PGE2 level. Similar to omeprazole, NPW treatment significantly reduced gastric and serum tumor necrosis factor-alpha and interleukin-1 beta levels and depressed the upregulation of nuclear factor kappa B (NF-κB) and COX-2 expressions due to ulcer. In parallel with the histopathological findings, treatment with NPW suppressed ulcer-induced increases in myeloperoxidase activity and malondialdehyde level and replenished glutathione level. However, the inhibitory effect of NPW on myeloperoxidase activity and NPW-induced increase in glutathione were not observed in the presence of COX-1 inhibitor ketorolac or the non-selective COX-inhibitor indomethacin.

SIGNIFICANCE

In conclusion, NPW facilitated the healing of gastric injury in rats via the inhibition of pro-inflammatory cytokine production, oxidative stress and neutrophil infiltration as well as the downregulation of COX-2 protein and NF-κB gene expressions.

Self-Nanoemulsion Intrigues the Gold Phytopharmaceutical Chrysin: In Vitro Assessment and Intrinsic Analgesic Effect

Chrysin is a natural flavonoid with a wide range of bioactivities. Only a few investigations have assessed the analgesic activity of chrysin. The lipophilicity of chrysin reduces its aqueous solubility and bioavailability. Hence, self-nanoemulsifying drug delivery systems (SNEDDS) were designed to overcome this problem. Kollisolv GTA, Tween 80, and Transcutol HP were selected as oil, surfactant, and cosurfactant, respectively. SNEDDS A, B, and C were prepared, loaded with chrysin (0.1%w/w), and extensively evaluated. The optimized formula (B) encompasses 25% Kollisolv GTA, 18.75% Tween 80, and 56.25% Transcutol HP was further assessed. TEM, in vitro release, and biocompatibility towards the normal oral epithelial cell line (OEC) were estimated. Brain targeting and acetic acid-induced writhing in a mouse model were studied. After testing several adsorbents, powdered SNEDDS B was formulated and evaluated. The surfactant/cosurfactant (S/CoS) ratio of 1:3 w/w was appropriate for the preparation of SNEDDS. Formula B exhibited instant self-emulsification, spherical nanoscaled droplets of 155.4 ± 32.02 nm, and a zeta potential of - 12.5 ± 3.40 mV. The in vitro release proved the superiority of formula B over chrysin suspension (56.16 ± 10.23 and 9.26 ± 1.67%, respectively). The biocompatibility of formula B towards OEC was duplicated (5.69 ± 0.03 µg/mL). The nociceptive pain was mitigated by formula B more efficiently than chrysin suspension as the writhing numbers reduced from 8.33 ± 0.96 to 0 after 60 min of oral administration. Aerosil R972 was selected as an adsorbent, and its chemical compatibility was confirmed. In conclusion, our findings prove the therapeutic efficacy of chrysin self-nanoemulsion as a potential targeting platform to combat pain.

Analysis of the permeable and retainable components of Cayratia japonica ointment through intact or broken skin after topical application by UPLC-Q-TOF-MS/MS combined with in vitro transdermal assay

Cayratia japonica ointment has been used for many years to promote wound healing after perianal abscess surgery. This study aimed to determine the skin-permeable and skin-retainable components of Cayratia japonica ointment after topical application to intact or broken skin via UPLC-Q-TOF-MS/MS analysis and in vitro transdermal assay. Moreover, a combination of semi-quantitative and molecular docking analyses was performed to identify the main active components of the Cayratia japonica ointment and the probable phases of the wound healing process that they act on. Modified vertical Franz diffusion cells and abdominal skin of rats were selected for the in vitro transdermal study. Mass spectrometry data were collected in both positive and negative ion modes. A total of 7 flavonoids (schaftoside, luteolin-7-O-glucuronide, luteolin-7-O-glucoside, apigenin-7-O-glucuronide, luteolin, apigenin, and chrysin) and 1 coumarin (esculetin), were found to permeate and/or retained by intact or broken skin. Among them, the flavonoids were more permeable through intact/broken skin and exhibited stronger binding affinities for targets related to the inflammatory and proliferative phases of wound healing. This study suggests that the flavonoids in Cayratia japonica ointment are most likely the main active components and are crucial at the inflammatory and proliferative phases of wound healing.

Bioflavonoids ameliorate crowding induced hemoglobin aggregation: a spectroscopic and molecular docking approach

The cellular environment is densely crowded, confining biomacromolecules including proteins to less available space. This macromolecular confinement may affect the physiological conformation of proteins in long-term processes like ageing. Changes in physiological protein structure can lead to protein conformational disorders including neurodegeneration. An intervention approach using food and plant derived bioflavonoids offered a way to find a treatment for these enervating pathological conditions as there is no remedy available. The bioflavonoids NAR (naringenin), 7HD (7 hydroxyflavanone) and CHR (chrysin) were tested for their ability to protect Hb (hemoglobin) against crowding-induced aggregation. Morphological and secondary structural transitions were studied using microscopic and circular dichroism experiments, respectively. The kinetic study was carried out using the relative thioflavin T assay. Molecular docking, AmylPred2, admetSAR and FRET were applied to understand the binding parameters of bioflavonoids with Hb and their drug likeliness. Isolated human lymphocytes were used as a cellular system to study the toxic effects of Hb aggregates. Redox perturbation and cytotoxicity were evaluated by DCFH-DA and MTT assays, respectively. This study suggests that bioflavonoids bind to Hb in the vicinity of aggregation prone amino acid sequences. Binding of the bioflavonoids stabilizes the Hb against crowding-induced structural alterations. Therefore, this study signifies the potential of bioflavonoids for future treatment of many proteopathies including neurodegeneration.Communicated by Ramaswamy H. Sarma.

Uro-protective role of chrysin against cyclophosphamide-induced hemorrhagic cystitis in rats involving the turning-off NF-κB/P38-MAPK, NO/PARP-1 and STAT-3 signaling cascades

BACKGROUND

Chemotherapeutic agents are used to treat a wide range of cancer types, but they cause serious side effects which must be managed after treatment. Cyclophosphamide (CYP) is one of chemotherapeutic drugs that causes hemorrhagic cystitis (HC) induced by acrolein.

OBJECTIVE

The current investigation intended to uncover the role of chrysin (CHR) in CYP-induced HC in rats and explore the signaling pathway beyond this effect.

ANALYSIS

process: A single dose of CYP (200 mg/kg/IP) was injected, meanwhile CHR (25, 50 and 100 mg/kg, P.O) was administered respectively for 7 days prior to CYP administration and resume for 7 days afterwards. Urinary bladder tissue was then isolated from all rats to assess oxidative stress and inflammatory biomarkers. Moreover, histopathological examinations were performed.

RESULTS

Treatment with CHR showed a marked alleviation in oxidative stress biomarkers induced by CYP. Furthermore, CHR treatment presented a dose-dependent boost in the anti-inflammatory; IL-10 levels and a drop in the pro-inflammatory biomarkers; IL-1β, IL-6, and TNF-α. Additionally, stabilization of the PARP-1 protein expression was also detected thus preventing DNA damage. Similarly, CHR restored the urinary bladder cGMP levels. Notably, CHR treatment was accompanied with inhibition in NF-κB/p38-MAPK, NO/PARP-1 and STAT-3 signaling pathways inflammatory cascades. All these findings conformed with the histopathological examinations as well as iNOS immunostaining in the urinary bladder tissue.

CONCLUSION

Co-administration of CHR and CYP attained uro-protective therapeutic potential to guard against HC as well as spot the tangled mechanism of CHR in attenuating the HC induced by CYP.

Liuwei Anxiao San protects gastric mucosa from gastric ulcer in rats by regulating the JAK2/STAT3 pathway

Mongolian medicine prescriptions are recognized as promising gastroprotective agents. This study is to explore the effects and mechanisms of Liuwei Anxiao San (LAS) in gastric ulcer (GU). GU rat models were established using acetic acid, followed by treatment with LAS at different doses and/or the JAK2 agonist Coumermycin A1 (CA1). The ulcerous area and inhibition rates were calculated. The mucosal damage and cell apoptosis in gastric tissues were assessed by H&E and TUNEL staining. The activities of SOD, GSH-Px, and CAT, and MDA levels were measured. The levels of pro-inflammatory and anti-inflammatory factors were determined by ELISA. The activation of the JAK2/STAT3 pathway was determined by Western blot. As the results suggested, LAS dose-dependently ameliorated gastric mucosal damage and inhibited oxidative stress and inflammatory response, evidenced by increased activities of SOD, GSH-Px, and CAT, decreased MDA level, increment of anti-inflammatory factors and decrement of pro-inflammatory factors, and inhibited the activation of the JAK2/STAT3 pathway in GU rats. CA1 partly abolished the function of LAS on gastric mucosal injury, oxidative stress, and inflammation in GU rats. In conclusion, LAS protects against gastric mucosal injury in GU rats through inhibition of oxidative stress and inflammation by suppressing the JAK2/STAT3 pathway.

Systematic Exploration of the Potential Material Basis and Molecular Mechanism of the Mongolian Medicine Shudage-4 in Attenuating Stress-Induced Gastric Ulcer in Rat

Shudage-4, an ancient and well-known formula in traditional Mongolian medicine comprising four different types of traditional Chinese medicine, is widely used in the treatment of gastric ulcers. However, the potential material basis and molecular mechanism of Shudage-4 in attenuating stress-induced gastric ulcers remain unclear. This study aimed to first explore the potential material basis and molecular mechanism of Shudage-4 in attenuating gastric ulcers in rats. The chemical constituents and transitional components in the blood of Shudage-4 were identified by ultra-performance liquid chromatography time-of-flight mass spectrometry (UPLC-TOF-MS). The rat gastric ulcer model was induced by water immersion restraint stress (WIRS). The ulcer damage to gastric tissue was measured at the gross anatomical level and pathological level by hematoxylin-eosin (HE) staining of gastric tissue. RNA sequencing of gastric tissue and plasma metabolomics were performed to analyze the mechanism of Shudage-4 against gastric ulcers. A Pearson correlation analysis was performed to explore the association between serum metabolites and gene expression of gastric tissue. A total of 30 chemical constituents were identified in Shudage-4 by UPLC-TOF-MS. Among 30 constituents, 13 transitional components in the blood were considered as the potential material basis. Shudage-4 treatment had a significant effect on WIRS-induced gastric ulcers in rats. HE staining of gastric tissue illustrated that WIRS-induced ulcer damage was suppressed by Shudage-4 treatment. RNA sequencing of gastric tissue showed that 282 reversed expression genes in gastric tissue were related to Shudage-4 treatment, and gene set enrichment analysis revealed that Shudage-4 treatment significantly inhibited gene set expression related to reactive oxygen species (ROS), which was also validated by detecting rat gastric tissue MDA, GSH, SOD, GSH-Px, and CAT activities. The plasma metabolomic data demonstrated that 23 significantly differential metabolites were closely associated with the Shudage-4 treatment. The further multiomics joint analysis found that significantly upregulated 5 plasma metabolites in Shudage-4-treated rats compared to model rats were negatively correlated with gene set expression related to ROS in gastric tissue. Shudage-4 alleviated WIRS-induced gastric ulcers by inhibiting ROS generation, which was achieved by regulating plasma metabolites level.

A mechanism of Sijunzi decoction on improving intestinal injury with spleen deficiency syndrome and the rationality of its compatibility

ETHNOPHARMACOLOGICAL RELEVANCE

Sijunzi Decoction (SJZD) is a renowned formula for the treatment of spleen deficiency syndrome (SDS) in traditional Chinese medicine (TCM). Its non-polysaccharides (NPS) component, dominated by various compounds of SJZD, has shown the remarkable efficacy in SDS, especially in gastrointestinal injury. However, the principle of compatibility of SJZD and the micro-mechanism of effect on SDS are still unclear.

AIM OF THE STUDY

To elucidate the scientific implications of SJZD compatibility and its micro-mechanism in the treatment of SDS-induced intestinal injury.

MATERIALS AND METHODS

First, the chemical composition of NPS in SJZD and incomplete SJZD (iSJZD, including SJZD-R, SJZD-A, SJZD-P, SJZD-G) were comprehensively analyzed by UPLC-QTOF-MS, and comparing their chemical composition by multivariate statistical analysis to reveal the effect of a single herb on SJZD compatibility. Second, network pharmacology and molecular docking were used to uncover the micro-mechanisms of potential active compounds in SJZD for the treatment of SDS, and develop an active component combination (ACC) by accurate quantification. Subsequently, the action of the potential active compounds and ACC was verified through in vivo and in vitro.

RESULTS

A total of 112, 77, 93, 87, and 67 compounds were detected in NPS of SJZD, SJZD-R, SJZD-A, SJZD-P, and SJZD-G, respectively. Changes in the chemical components of SJZD_NPS and iSJZD_NPS revealed that RG and RAM, as well as RAM and Poria significantly affected the dissolution of each other's chemical components, and the co-decoction of four herbs promoted the dissolution of the active compounds and inhibited toxic compounds. Furthermore, network pharmacology showed that 274 compounds of 15 categories in SJZD_NPS acted on the 186 key targets to treat SDS by inhibiting inflammation, enhancing immunity, and regulating gastrointestinal function and metabolism. Finally, through in vitro experiments, six compounds among 18 potential compounds were verified to markedly repair intestinal epithelium injury by modulating the FAK/PI3K/Akt or LCK/Ras/PI3K/Akt signaling pathway. It is worth mentioning that ACC, composed of 11 compounds accurately quantified, demonstrated significant in vivo treatment effects on intestinal damage with SDS similar to NPS or SJZD.

CONCLUSIONS

This study elucidates the scientific evidence of the "Jun-Chen-Zuo-Shi" and "detoxification and synergistic" in the decocting process of SJZD. An ACC, the active component of SJZD, ameliorate SDS-induced intestinal injury by the FAK/PI3K/Akt signaling pathway, which provides a strategy for screening alternatives to effective combinations of TCMs.

Effect of melatonin on electrical impedance and biomarkers of damage in a gastric ischemia/reperfusion model

The damage to the gastrointestinal mucosa induced by ischemia/reperfusion (I/R) is closely related to high mortality in critically ill patients, which is attributable, in part, to the lack of an early method of diagnosis to show the degree of ischemia-induced injury in this type of patients. Electrical Impedance Spectroscopy (EIS) has been shown to be a tool to early diagnose gastric mucosal damage induced by ischemia. A therapeutic alternative to reduce this type of injury is melatonin (MT), which has gastroprotective effects in I/R models. In this work, the effect of treatment with MT on the electrical properties of gastric tissue, biomarkers of inflammatory (iNOS and COX-2), proliferation, and apoptotic process under I/R conditions in male Wistar rats was evaluated through EIS, histological and immunohistochemical analysis. Treatment with MT prevents gastric mucosa damage, causing a decrease in gastric impedance parameters related to the inflammatory process and cellular damage. This suggests that EIS could be used as a tool to diagnose and monitor the evolution of gastric mucosal injury, as well as in the recovery process in critically ill patients.

Mechanism exploration of ancient pharmaceutic processing (Paozhi) improving the gastroprotective efficacy of Aucklandiae Radix

ETHNOPHARMACOLOGICAL RELEVANCE

Processing, also called Paozhi in Chinese, is an ancient Chinese pharmaceutic processing technique developed along with the Chinese herbal medicines (CHMs). The understanding of the mechanism of Paozhi has been investigated for several decades. Aucklandiae Radix (CAR) and its roasted processed products are all used in indigestion as a kind of CHMs. Processed Aucklandiae Radix (PAR) had a stronger effect to protect gastric mucosa than CAR, while the main compounds in CAR were reduced sharply after being processed. The underlying mechanism of this phenomenon is still unclear.

AIM OF THE STUDY

This study was aimed to evaluate whether PAR have a stronger gastroprotective effect than CAR and the underlying mechanisms of such circumstance.

MATERIALS AND METHODS

Ultra-fast liquid chromatography coupled with quadrupole time of flight mass spectrometry (UFLC-QTOF-MS/MS) coupled with multivariate statistical analyses was employed to explore chemical compounds which had a relatively stable content in PAR. Based on the compounds selected as the research object, network pharmacology was applied to visualize the relationships between the selected components and the gastroprotective-related targets from disease database, at the same time the possible intervention path of CAR/PAR which might be responsible for the effect of CAR/PAR on gastritis-induced rats was also built. Then, the key proteins were detected by western blotting to verify and compare the pharmacological effects of CAR/PAR.

RESULTS

Through UFLC-QTOF-MS/MS and orthogonal partial least squares discriminant analysis (OPLS-DA), sixteen compounds stable in PAR were discovered, of which saussureamine C and saussureamine B were estimated as the core compounds to exert gastroprotective in PAR predicted by network pharmacology analysis. Under the guide of KEGG pathway enrichment analysis, PI3K/AKT, p38 MAPK (Mitogen-activated protein kinase) and nuclear factor-kappa B (NF-κB) signaling pathways were forecasted as the possible healing mechanisms of CAR/PAR, and that result was verified by the experiments in vivo. PAR performed a stronger ability to reduce the level of p38 MAPK and NF-κB p65 than CAR, which may partially explain the different ability of CAR/PAR against gastric mucosa damage.

CONCLUSION

This study clarified that although Paozhi entailed a sharp decrease on the main compounds of CAR, there were some compounds which were not sensitive to high temperature and preserved in PAR and had a relative higher content in PAR than in CAR. PAR has stronger influence on MAPKs/NF-κB signaling pathway than CAR, which may reveal that the stronger gastroprotective effect of PAR perhaps rely on the constitutions with a higher relative abundance after Paozhi. The present research combined UFLC-QTOF-MS/MS and network pharmacology deeply investigated the impact of the roasted processing on the chemical constitutions and gastroprotective effect of CAR and offered reference for the clinical application of CAR/PAR.

RETRACTED: mPEG-b-P(Glu-co-Phe) nanoparticles increase gastric retention time and gastric ulcer treatment efficacy of 20(S)-ginsenoside Rg3

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). On behalf of all authors, the corresponding author, Jiannan Li, is retracting the above article. The authors informed the journal that they mistakenly provided inappropriate H&E and EGFR immunohistochemical images for the Rg3-NPs group in Fig. 9 of the published article. The results in Fig. 9D cannot be reproduced as originally published. Importantly, in the present version, Rg3-NPs groups do not show an EGFR promotion effect compared to Rg3 and Cimetidine groups. Therefore, their final results and conclusions are not supported. The authors sincerely apologise to the editors and journal readership for these oversights and inconvenience that this may have caused.

Protective effect of chrysin on indomethacin induced gastric ulcer in rats: role of multi-pathway regulation

We investigated the potential gastroprotective effects of chrysin on indomethacin induced gastric ulcers in rats. We used six groups of animals: control; indomethacin (Indo); reference (Ulcuran®); indomethacin + 25 mg/kg chrysin (Indo + CHR25); indomethacin + 50 mg/kg chrysin (Indo + CHR50); indomethacin + 100 mg/kg chrysin (Indo + CHR100). All doses of chrysin were given orally to rats before indomethacin. Gastric lesions were examined macroscopically and microscopically. The effects of treatment with chrysin were assessed versus a single dose of 30 mg/kg Ulcuran® (generic ranitidine) as reference standard. We also investigated gastric mucosal superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT), malonaldehyde (MDA) and arginase activities, and COX-2, PGE₂, iNOS, TNF-α, IL-1β, NFκB, MPO, Bax, caspase-3 and 8-OHdG levels. We assessed caspase-3 and Bax levels using immunohistochemistry. Compared to the control and reference groups, SOD, CAT, GPx and arginase activities and GSH levels decreased, and MDA levels increased in the indomethacin induced gastric ulcer group. iNOS, TNF-α, IL-1β, NFκB, MAPK-14, MPO, Bax and 8-OHdG levels were increased in the indomethacin treated gastric group, while COX-2 activity and PGE₂ levels were decreased. The three doses of chrysin co-administered with indomethacin increased COX-2 activity and PGE₂ levels in rats with ulcers. Chrysin exhibited gastroprotective effects on indomethacin induced gastric ulcer due to its antioxidant, anti-inflammatory and anti-apoptotic activities.

Developing nutritional component chrysin as a therapeutic agent: Bioavailability and pharmacokinetics consideration, and ADME mechanisms

Chrysin is a promising naturally occurring flavonoid mainly found in honey and propolis. Although chrysin's biological activities have been demonstrated and the mechanism of actions has been determined using in vitro and in vivo models, results from the current clinical studies were largely negative. A potential reason for chrysin's low efficacy in humans is poor oral bioavailability. In this paper, we reviewed the preclinical and clinical pharmacokinetics studies of chrysin and analyzed the mechanism of poor in vivo efficacy with emphasis on its bioavailability and ADME mechanism. Low aqueous solubility, rapid metabolism mediated by UGTs and SULT, efficient excretion through efflux transporters including BCRP and MRP2 are the major reasons causing poor systemic bioavailability for chrysin. However, because of efficient enterohepatic recycling facilitated by phase II metabolism and efflux, chrysin's bioavailability in the low GI tract is high. Thus, chrysin can be ideal for treating diseases in the terminal ileum and colon (e.g., carcinoma, local infection) since it is localized in the lower GI tract with limited delivery to other organs.

Bioelectric, tissue, and molecular characteristics of the gastric mucosa at different times of ischemia

Gastrointestinal ischemia may be presented as a complication associated with late shock detection in patients in critical condition. Prolonged ischemia can cause mucosal integrity to lose its barrier function, triggering alterations that can induce organ dysfunction and lead to death. Electrical impedance spectroscopy has been proposed to identify early alteration in ischemia-induced gastric mucosa in this type of patients. This work analyzed changes in impedance parameters, and tissue and molecular alterations that allow us to identify the time of ischemia in which the gastric mucosa still maintains its barrier function. The animals were randomly distributed in four groups: Control, Ischemia 60, 90, and 120 min. Impedance parameters were measured and predictive values were determined to categorize the degree of injury using a receiver operating characteristic curve. Markers of inflammatory process and apoptosis (iNOS, TNFα, COX-2, and Caspase-3) were analyzed. The largest increase in impedance parameters occurred in the ischemia 90 and 120 min groups, with resistance at low frequencies (RL) and reactance at high frequencies (XH) being the most related to damage, allowing prediction of the occurrence of reversible and irreversible tissue damage. Histological analysis and apoptosis assay showed progressive mucosal deterioration with irreversible damage (p < 0.001) starting from 90 min of ischemia. Furthermore, a significant increase in the expression of iNOS, TNFα, and COX-2 was identified in addition to apoptosis in the gastric mucosa starting from 90 min of ischemia. Tissue damage generated by an ischemia time greater than 60 min induces loss of barrier function in the gastric mucosa.

Chrysin's Impact on Oxidative and Inflammation Damages in the Liver of Aged Male Rats

AIM

The purpose of this research was to investigate the effect of chrysin on one of the natural antioxidants on aging progression in an animal model.

BACKGROUND

Oxidative stress and inflammation increase in hepatic tissue during aging, leading to liver dysfunction.

OBJECTIVE

The current research was conducted to show the effect of chrysin on the activities of antioxidant enzyme (catalase, glutathione peroxidase, and superoxide dismutase), serum nitric oxide (NO), and lipid peroxidation as well as inflammatory cytokines (TNF-α, IL-6, and IL-1β) of aging rats.

METHODS

Male Wistar rats of different ages, 2, 10, and 20 months, were randomly divided into six groups as follows (n=8, per each group): young control rats (C2), young CH-treated rats (CH2), middle- aged control rats (C10), middle-aged CH-treated group (CH10), aged control group (C20), and aged CH-treated group (CH20). Chrysin (20 mg/kg) was administered intraperitoneally once a day for 30 days.

RESULT

Present findings indicated that chrysin treatment ameliorated the increased liver levels of lipid peroxidation, TNF-α, and IL-1β as well as serum levels of NO.

CONCLUSION

The findings suggest that chrysin could be effective against the progression of ageinduced damage by modulation of oxidant-antioxidant system and inflammatory response.

Molecular Docking Analysis of Flavonoid Compounds with Matrix Metalloproteinase- 8 for the Identification of Potential Effective Inhibitors

Background:

Matrix metalloproteinase-8 (MMP-8) participates in the degradation of different types of collagens in the extracellular matrix and basement membrane. Up-regulation of the MMP-8 has been demonstrated in many disorders including cancer development, tooth caries, periodontal/ peri-implant soft and hard tissue degeneration, and acute/chronic inflammation. Therefore, MMP-8 has become an encouraging target for therapeutic procedures for scientists. We carried out a molecular docking approach to study the binding affinity of 29 flavonoids, as drug candidates, with the MMP-8. Pharmacokinetic and toxicological properties of the compounds were also studied. Moreover, it was attempted to identify the most important amino acids participating in ligand binding based on the degree of each of the amino acids in the ligand-amino acid interaction network for MMP-8.

Methods:

Three-dimensional structure of the protein was gained from the RCSB database (PDB ID: 4QKZ). AutoDock version 4.0 and Cytoscape 3.7.2 were used for molecular docking and network analysis, respectively. Notably, the inhibitor of the protein in the crystalline structure of the 4QKZ was considered as a control test. Pharmacokinetic and toxicological features of compounds were predicted using bioinformatics web tools. Post-docking analyses were performed using BIOVIA Discovery Studio Visualizer version 19.1.0.18287.

Results and Discussions:

According to results, 24 of the studied compounds were considered to be top potential inhibitors for MMP-8 based on their salient estimated free energy of binding and inhibition constant as compared with the control test: Apigenin-7-glucoside, nicotiflorin, luteolin, glabridin, taxifolin, apigenin, licochalcone A, quercetin, isorhamnetin, myricetin, herbacetin, kaemferol, epicatechin, chrysin, amentoflavone, rutin, orientin, epiafzelechin, quercetin-3- rhamnoside, formononetin, isoliquiritigenin, vitexin, catechine, and isoquercitrin. Moreover, His- 197 was found to be the most important amino acid involved in the ligand binding for the enzyme.

Conclusion:

The results of the current study could be used in the prevention and therapeutic procedures of a number of disorders such as cancer progression and invasion, oral diseases, and acute/chronic inflammation. Although, in vitro and in vivo tests are inevitable in the future.

Hunan insect tea polyphenols provide protection against gastric injury induced by HCl/ethanol through an antioxidant mechanism in mice

The purposes of this study were to explore the preventive and treatment effects of Hunan insect tea polyphenols (HITPs) on gastric injury in mice induced by HCl/ethanol and to investigate their molecular mechanisms of action. Both HITPs and ranitidine inhibited the formation and further deterioration of gastric mucosal lesions, reduced the secretion of gastric juice, and raised gastric juice pH compared to the control. The HITPs-H treated group had lower serum levels of motilin, substance P, and endothelin than the control group, but they had higher serum levels of vasoactive intestinal peptide and somatostatin. Mice treated with HITPs had lower serum levels of cytokines interleukin (IL)-6, IL-12, tumor necrosis factor-α (TNF-α), and interferon-γ than the control group. The activities of superoxide dismutase (SOD), nitric oxide, and glutathione peroxidase (GSH-Px) were higher in the gastric tissues of HITP-treated mice, but the malondialdehyde content was lower. Quantitative PCR analysis indicated that the mRNA expression of occludin, epidermal growth factor (EGF), EGF receptor (EGFR), vascular EGF (VEGF), inhibitor kappaB-α, cuprozinc-superoxide dismutase, manganese-superoxide dismutase, GSH-Px, neuronal nitric oxide synthase, and endothelial NOS increased significantly in the gastric tissues of HITP-treated mice. However, the activated B cell, inducible NOS, cyclooxygenase-2, TNF-α, IL-1 beta, and IL-6 mRNA expression levels in the HITPs group were lower than those in the control group. The protective effect of a high concentration (200 mg per kg bw) of HITPs on gastric injury induced by HCl/ethanol was stronger than that of a low concentration (100 mg per kg bw) of HITPs. High-performance liquid chromatography (HPLC) revealed that the HITPs contained cryptochlorogenic acid, (-)-epicatechin gallate, and isochlorogenic acid C. Taken together, our findings indicate that the HITPs played a role in the prevention of gastric damage. The antioxidant effect of the HITPs contributed to their potential value in the prevention and treatment of gastric injury. HITPs have broad prospects as biologically active substances for food development.

A Review of the Role of Flavonoids in Peptic Ulcer (2010-2020)

Peptic ulcers are characterized by erosions on the mucosa of the gastrointestinal tract that may reach the muscle layer. Their etiology is multifactorial and occurs when the balance between offensive and protective factors of the mucosa is disturbed. Peptic ulcers represent a global health problem, affecting millions of people worldwide and showing high rates of recurrence. Helicobacter pylori infection and the use of non-steroidal anti-inflammatory drugs (NSAIDs) are one of the most important predisposing factors for the development of peptic ulcers. Therefore, new approaches to complementary treatments are needed to prevent the development of ulcers and their recurrence. Natural products such as medicinal plants and their isolated compounds have been widely used in experimental models of peptic ulcers. Flavonoids are among the molecules of greatest interest in biological assays due to their anti-inflammatory and antioxidant properties. The present study is a literature review of flavonoids that have been reported to show peptic ulcer activity in experimental models. Studies published from January 2010 to January 2020 were selected from reference databases. This review refers to a collection of flavonoids with antiulcer activity in vivo and in vitro models.

Broad-Spectrum Preclinical Antitumor Activity of Chrysin: Current Trends and Future Perspectives

Pharmacological profile of phytochemicals has attracted much attention to their use in disease therapy. Since cancer is a major problem for public health with high mortality and morbidity worldwide, experiments have focused on revealing the anti-tumor activity of natural products. Flavonoids comprise a large family of natural products with different categories. Chrysin is a hydroxylated flavonoid belonging to the flavone category. Chrysin has demonstrated great potential in treating different disorders, due to possessing biological and therapeutic activities, such as antioxidant, anti-inflammatory, hepatoprotective, neuroprotective, etc. Over recent years, the anti-tumor activity of chrysin has been investigated, and in the present review, we provide a mechanistic discussion of the inhibitory effect of chrysin on proliferation and invasion of different cancer cells. Molecular pathways, such as Notch1, microRNAs, signal transducer and activator of transcription 3 (STAT3), nuclear factor-kappaB (NF-κB), PI3K/Akt, MAPK, etc., as targets of chrysin are discussed. The efficiency of chrysin in promoting anti-tumor activity of chemotherapeutic agents and suppressing drug resistance is described. Moreover, poor bioavailability, as one of the drawbacks of chrysin, is improved using various nanocarriers, such as micelles, polymeric nanoparticles, etc. This updated review will provide a direction for further studies in evaluating the anti-tumor activity of chrysin.

TMEM16A-encoded anoctamin 1 inhibition contributes to chrysin-induced coronary relaxation

BACKGROUND

Chrysin, a natural flavonoid available in honey, propolis and medicinal plants, has been shown to be vasorelaxant in some vascular beds. Proper intake of an alimental vasodilator as a food additive may be a promising strategy for prevention and treatment of coronary spasmodic disorders.

PURPOSE

TMEM16A-encoded anoctamin 1 (ANO1), a Ca²⁺ activated Cl^- channel (CaCC), plays an important role in the modulation of vascular tone. We tested the possibility that inhibition of CaCCs contributes to chrysin-induced coronary arterial relaxation.

METHODS

The vascular tone of the rat coronary artery (RCA) was recorded with a wire myograph. CaCC currents were assessed using whole-cell patch clamp in arterial smooth muscle cell (ASMC) freshly isolated from RCAs. An inhibitor study was performed to explore the mechanisms underlying the vasomotor and electrophysiological effects of chrysin.

RESULTS

Pre-incubation with chrysin depressed the contractions elicited by thromboxane A2 analog U46619, vasopressin (VP), depolarization and extracellular Ca²⁺ elevation/depolarization without significant preference among these vasoconstrictors. Besides, chrysin inhibited both intracellular Ca²⁺ release-dependent and extracellular Ca²⁺ influx-dependent components of contractions induced by U46619 or VP. In RCAs pre-contracted with U46619, VP or KCl, chrysin elicited concentration-dependent relaxations, which were weakened by Cl^- -deprivation. The electrophysiological study showed that chrysin reduced ANO1-antibody-sensitive CaCC currents and depressed CaCC increments induced by U46619. Inhibitor study showed that both the vasorelaxation and the CaCC current reduction induced by chrysin were attenuated by blocking CaCCs and inhibiting cAMP/PKA and NO/PKG pathways.

CONCLUSION

The present findings indicate that inhibition of RCA ASMC CaCC currents, which may be consequential following intracellular Ca²⁺ availability reduction and activation of cAMP/PKA and NO/cGMP signaling pathways, contributes to chrysin-induced RCA relaxation.