Apocynin protects against ethanol-induced gastric ulcer in rats by attenuating the upregulation of NADPH oxidases 1 and 4

Integrated network pharmacology and metabolomics to investigate the effects and possible mechanisms of Dehydroevodiamine against ethanol-induced gastric ulcers

ETHNOPHARMACOLOGICAL RELEVANCE

Tetradium ruticarpum (A.Juss.) T.G.Hartley, a traditional Chinese medicine with thousands of years of medicinal history, has been employed to address issues such as indigestion, abdominal pain, and vomiting. Dehydroevodiamine (DHE) is a quinazoline alkaloid extracted from traditional Chinese medicine Tetradium ruticarpum (A.Juss.) T.G.Hartley. Previous studies have shown that DHE has anti-inflammatory, analgesic, and antioxidant activities. However, it is still unclear whether DHE has an effect on ethanol-induced gastric ulcers.

AIM OF THE STUDY

The objective of this study is to investigate the therapeutic efficacy and underlying mechanisms of action of DHE on ethanol-induced gastric ulcers using network pharmacology and metabolomics strategies.

METHODS

In this study, we used ethanol-induced rats as a model to assess the efficacy of DHE by biochemical indicator assays and pathological tissue detection. The integration of network pharmacology and metabolomics was used to explore possible mechanisms and was validated by western blot experiments. Finally, molecular docking was used to analyze the binding energy between DHE and the targets of PIK3CG and PLA2G2A.

RESULTS

DHE was able to reverse ethanol-induced abnormalities in biochemical indicators and improve pathological tissue. Network pharmacology results indicated that DHE may be involved in the regulation of gastric ulcers by modulating 79 targets, and metabolomics results showed that a total of 13 metabolites were changed before and after DHE administration. Integrating network pharmacology and metabolomics, PIK3CG and PLA2G2A were identified as possible targets to exert therapeutic effects. In addition, the MAPKs pathway may also be involved in the regulation of ethanol-induced gastric ulcers. Finally, molecular docking results showed that DHE had low binding energies with both PIK3CG and PLA2G2A.

CONCLUSIONS

These findings suggest that DHE was able to exert a protective effect against ethanol-induced gastric ulcers by modulating multiple metabolites with multiple targets. This study provides a valuable reference for the development of antiulcer drugs.

Unravelling the Gastroprotective Potential of Kefir: Exploring Antioxidant Effects in Preventing Gastric Ulcers

The present study was conducted to evaluate the protective effect of milk kefir against NSAID-induced gastric ulcers. Male Swiss mice were divided into three groups: control (Vehicle; UHT milk at a dose of 0.3 mL/100 g), proton pump inhibitor (PPI; lansoprazole 30 mg/kg), and 4% milk kefir (Kefir; 0.3 mL/100 g). After 14 days of treatment, gastric ulcer was induced by oral administration of indomethacin (40 mg/kg). Reactive oxygen species (ROS), nitric oxide (NO), DNA content, cellular apoptosis, IL-10 and TNF-α levels, and myeloperoxidase (MPO) enzyme activity were determined. The interaction networks between NADPH oxidase 2 and kefir peptides 1-35 were determined using the Residue Interaction Network Generator (RING) webserver. Pretreatment with kefir for 14 days prevented gastric lesions. In addition, kefir administration reduced ROS production, DNA fragmentation, apoptosis, and TNF-α systemic levels. Simultaneously, kefir increased NO bioavailability in gastric cells and IL-10 systemic levels. A total of 35 kefir peptides showed affinity with NADPH oxidase 2. These findings suggest that the gastroprotective effect of kefir is due to its antioxidant and anti-inflammatory properties. Kefir could be a promising natural therapy for gastric ulcers, opening new perspectives for future research.

In vivo and In silico evidence of the protective properties of carvacrol against experimentally-induced gastric ulcer: Implication of antioxidant, anti-inflammatory, and antiapoptotic mechanisms

Gastric ulcer is a serious disease that affects millions of individuals worldwide. Alcohol consumption is a major contributor to the disease pathogenesis and ethanol-induced ulcer in rats closely recapitulates the clinical pathology of ulcer. In this study, rats were pretreated with carvacrol (CAR,50 and 100 mg/kg, orally) 1 h before absolute ethanol administration to induce gastric ulcer. CAR prevented ethanol-induced increases in gastric volume and acidity while restored mucin content. The gastro-protective activity of CAR, particularly the higher dose (100 mg/kg), was further supported by histopathological examination, as manifested by reduced gastric lesions. Interestingly, oxidative stress is linked to early stages of ulcer development and progression. In this study, ethanol administration upregulated the levels of ROS-producing enzymes, NADPH oxidase homologs 1 and 4 (Nox1 and Nox4) and lipid peroxides while depleting the antioxidant defense mechanisms, including GSH, Glutathione Peroxidase (GPX) and catalase. Interestingly, these alterations were significantly ameliorated by CAR pretreatment. Additionally, CAR possesses anti-inflammatory and anti-apoptotic activities. Pretreatment with CAR blunted ethanol-induced increases in inflammatory cytokines (NF-κB and TNF-α) and rectified the apoptosis regulator (Bax/Bcl2 ratio) in gastric tissue. Moreover, the docking simulation of CAR illustrated good fitting and interactions with GPX, Nox1 and TNF-α through the formation of hydrogen and hydrophobic (pi-H) bonds with conservative amino acids, thus, further supporting the anti-inflammatory and antioxidant effects underlying the gastroprotective effects of CAR. In conclusion, this study elucidates, using in silico and in vivo models, that the gastroprotective activity of CAR is attributed, at least in part, to its mucin-secretagogue, antioxidative, anti-inflammatory, and anti-apoptotic mechanisms.

Gastroprotective effect of dapagliflozin in ethanol-induced gastric lesions in rats: Crosstalk between HMGB1/RAGE/PTX3 and TLR4/MyD88/VEGF/PDGF signaling pathways

Alcohol abuse may lead to the development of gastric mucosal lesions. Dapagliflozin (DAPA), a sodium-glucose cotransporter-2 inhibitor, is clinically used to treat type 2 diabetes mellitus. However, studies showed protective effect of DAPA under various experimental conditions by alleviating oxidative stress and inflammation. The effect of DAPA on experimental gastric ulcer has not been studied yet. Therefore, we attempted to investigate DAPA's protective effect against ethanol (EtOH)-induced gastric lesions. Fifty-six (8-week-old) male Wistar rats were divided into seven groups. DAPA (1, 5, and 10 mg/kg/day; p.o.) was given for seven days, plus a single dose of absolute EtOH (5 ml/kg) on day 8. According to hematoxylin and eosin, and Alcian blue staining of gastric tissue sections, titratable acidity, and macroscopic assessments, DAPA high dose (10 mg/kg) was the most protective, with lesser ulcerations, and higher mucin, relative to the lower two doses and the standard treatment omeprazole (OME). In rats pre-treated with DAPA high dose, colorimetric and ELISA analyses revealed significantly decreased oxidative stress, pro-inflammatory, and apoptosis indices and increased levels of platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF). Western blot analysis revealed reduced pentraxin-3 (PTX3), high-mobility group box 1 (HMGB1), receptor for advanced glycation end products (RAGE), toll-like receptor 4 (TLR4), and myeloid differentiation factor 88 (MyD88) expression. These results were comparable in DAPA (10 mg/kg) and OME pre-treated groups. Overall, DAPA exerted a dose-dependent protective effect against EtOH-induced gastric injury. Gastroprotective effects of DAPA (10 mg/kg) may be associated with influencing HMGB1/RAGE/PTX3 and TLR4/MyD88/VEGF/PDGF pathways.

Amelioration of ethanol-induced gastric ulcer in rats by quercetin: implication of Nrf2/HO1 and HMGB1/TLR4/NF-κB pathways

Gastric ulcer is a serious medical condition that can be developed due to an imbalance in the protective and destructive factors of the gastric system. Available therapies do not provide definite cure, thus, there is an urge to seek for alternative treatments. Quercetin is a natural flavonoid that possesses antioxidant and anti-inflammatory properties. In the current study, the antiulcerogenic effect of quercetin in ethanol-induced gastric ulcer (EI-GU) rat model was compared to Antodine® (a reference drug), to elucidate the potential underlying mechanisms. Quercetin (50 mg/kg) and Antodine® (20 mg/kg) were given orally for one week post ulcer induction by ethanol. EI-GU was associated with downregulation of SOD, CAT, Nrf2 and HO1, and accompanied by upregulation of inflammatory markers (i.e., HMGB1, NF-κB and TNFα) and an increase in Bax/Bcl2 ratio. Administration of quercetin resulted in a significant reduction in gastric volume in the stomach of ulcerative rats by 86% and a significant decrease in gastric lesion count by 3.5- folds, as compared with the ulcerative rats. Moreover, rats treated with quercetin showed upregulation of Nrf2 by 3.3-fold change and in HO1 by 3.5-fold change when compared to ulcerated rats, and decreased HMGB1, TLR4, NF-κB p65 and TNF-α by 50%, 53%, 52.9% and 54.9%, respectively. Treatment of rats with quercetin reduced Bax and Bax/Bcl2 ratio and increased Bcl2 relative to ulcerated rats. Thus, it can be concluded that the ulcerogenic curative properties of quercetin were mediated by antioxidant, anti-inflammatory and antiapoptotic activities.

Antiulcerogenic and antioxidant activities of Plantago ovata ethanolic extract in rats

This study aimed to determine the antiulcerogenic and antioxidant activities of Psyllium (Plantago ovata Forssk) seed ethanolic extract in rats. We assessed the antioxidant potential using free radical scavenging on DPPH, β-carotene bleaching activity, ferric reducing power, and hydroxyl radical scavenging activity. In the antiulcerogenic study, pre-treatment with Plantago ovata seeds ethanolic extract (POE) (400 mg/kg b.wt) significantly protected against ethanol-induced gastric ulcer in rats by decreasing the ulcer index value and preserving the integrity of the gastric mucosa. The oxidative stress status in the stomach tissues showed a significant increase in the antioxidant enzyme levels of superoxide dismutase, catalase, and glutathione peroxidase with a significant decrease in lipid peroxidation during pre-treatment with POE. In conclusion, the POE protects against gastric ulcer due to its antioxidant potential and presence of bioactive molecules.

Formulation, optimization and characterization of allantoin-loaded chitosan nanoparticles to alleviate ethanol-induced gastric ulcer: in-vitro and in-vivo studies

Allantoin (ALL) is a phytochemical possessing an impressive array of biological activities. Nonetheless, developing a nanostructured delivery system targeted to augment the gastric antiulcerogenic activity of ALL has not been so far investigated. Consequently, in this survey, ALL-loaded chitosan/sodium tripolyphosphate nanoparticles (ALL-loaded CS/STPP NPs) were prepared by ionotropic gelation technique and thoroughly characterized. A full 24 factorial design was adopted using four independently controlled parameters (ICPs). Comprehensive characterization, in vitro evaluations as well as antiulcerogenic activity study against ethanol-induced gastric ulcer in rats of the optimized NPs formula were conducted. The optimized NPs formula, (CS (1.5% w/v), STPP (0.3% w/v), CS:STPP volume ratio (5:1), ALL amount (13 mg)), was the most convenient one with drug content of 6.26 mg, drug entrapment efficiency % of 48.12%, particle size of 508.3 nm, polydispersity index 0.29 and ζ-potential of + 35.70 mV. It displayed a sustained in vitro release profile and mucoadhesive strength of 45.55%. ALL-loaded CS/STPP NPs (F-9) provoked remarkable antiulcerogenic activity against ethanol-induced gastric ulceration in rats, which was accentuated by histopathological, immunohistochemical (IHC) and biochemical studies. In conclusion, the prepared ALL-loaded CS/STPP NPs could be presented to the phytomedicine field as an auspicious oral delivery system for gastric ulceration management.

Gastroprotective Effects of Inulae Flos on HCl/Ethanol-Induced Gastric Ulcers in Rats

Inulae Flos, the flower of Inula britannica L., is used as a dietary supplement, beverage, and medicine in East Asia. In this study, we evaluated the gastroprotective effects of Inulae Flos extract (IFE) against gastric mucosal lesions induced by hydrochloric acid (HCl)/ethanol in rats and explored its potential mechanisms by measuring antioxidant enzyme activity, mucus secretion, and prostaglandin E₂ (PGE₂) levels. Pretreatment with IFE at doses of 100 and 300 mg/kg significantly inhibited gastric lesions in HCl/ethanol-treated rats. IFE increased the activities of superoxide dismutase and catalase and the levels of glutathione and PGE₂ in gastric tissues. The administration of IFE also significantly increased the gastric wall mucus contents in HCl/ethanol-induced gastric lesions. These findings suggest that IFE has gastroprotective effects against HCl/ethanol-induced gastric lesions and exerts these effects through increased antioxidant levels and gastric mucus secretion. Inulae Flos may be a promising agent for the prevention and treatment of gastritis and gastric ulcers.

DUOX2, a common modulator in preventive effects of monoamine-based antidepressants on water immersion restraint stress- and indomethacin- induced gastric mucosal damage

Multiple kinds of monoamine-based antidepressants have been shown prophylactic effects in experimentally induced gastric ulcer. The loss of redox homeostasis plays a principle role in the development of peptic mucosal damage. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases are one of the most important sources of reactive oxygen species within the gastrointestinal tract. It is unclear whether there are some common NADPH oxidases modulated by monoamine-based antidepressants in different gastric mucosal damage models. We explored the effects of selective serotonin-norepinephrine reuptake inhibitor (SNRI) duloxetine on the reactive oxygen species production and antioxidant capacity in the gastric mucosa of water immersion restraint (WIRS) or indomethacin treated rats, and examined the role of NADPH oxidases in the protective effects. Pretreated duloxetine prevented the increase of gastric mucosal NADPH oxidase activity and NADPH oxidase inhibitor apocynin dose-dependently protected gastric mucosa from damage by the two factors. Furthermore, dual oxidase 2 (DUOX2) and NADPH oxidase4 (NOX4) are involved in the protective effects of duloxetine in both models. We then examined NADPH oxidases expression modulated by the other monoamine-based antidepressants including selective serotonin reuptake inhibitor (SSRIs) fluoxetine, tricyclic agent (TCAs) amitriptyline and monoamine oxidase inhibitor (MAOs) moclobemide in the two models, and all the three antidepressants reduced the DUOX2 expression in the gastric mucosa. So DUOX2 was a common modulator in the preventive effects of all the monoamine-based antidepressants on WIRS- and indomethacin-induced gastric lesion. Our work provided a peripheral joint molecular target for monoamine modulatory antidepressants, which may be helpful to reveal the mechanisms of this kind of drugs more than monoamine regulation.

Comparative study of raw and processed Vladimiriae Radix on pharmacokinetic and anti-acute gastritis effect through anti-oxidation and anti-inflammation

BACKGROUND

Vladimiriae Radix (VR) is the dry root of Vladimiria souliei (Franch.) Ling or Vladimiria souliei (Franch.) Ling var. cinerea Ling. Costunolide (CO) and dehydrocostus lactone (DE) are the two most effective active ingredients of VR. Raw Vladimiriae radix (rVR) and processed Vladimiriae radix (pVR) are the two most common forms. They have been used for hundreds of years to treat gastritis, gastric ulcer and gastrointestinal pain, but their protective effects on gastric mucosa have been widely considered to be different, and the mechanism is not clear.

PURPOSE

A comparative study of in vivo process and efficacy difference of raw and processed Vladimiriae Radix was carried out to explore the treatment mechanism and to provide reference for the rationality of clinical usage.

METHODS

In this study, multi-batch rVR and pVR were used to establish the characteristic chromatograms through high performance liquid chromatography (HPLC) to control the qualities of their extracts. A rapid and accurate ultra-high performance liquid chromatography - mass spectrometry (UPLC-MS) method was established and verified, and the concentrations of CO and DE in plasma of rats after oral administration were determined to analyze the pharmacokinetics. The anti-inflammatory and antioxidant activities of ethanol-induced acute gastric mucosa injury (AGMI) in rats were quantitatively analyzed by ELISA and Westernblot methods.

RESULTS

Characteristic chromatograms study showed that there were 9 common characteristic peaks between the chromatograms of rVR and pVR, and there was a high level (> 0.90) of the similarity between batches (only one batch less than 0.90). The increased levels of Tmax, T1/2 and MRT were found in rats treated with the pVR. Animal model studies indicated that both the two forms of VR could relieve AGMI, but pVR could more effectively reduce the content of ethanol in blood and lower the levels of TNF-α, IL-6, IL-1β, NO, iNOS and MDA, and increase the level of SOD. Results of Westernblot proved that pVR also could inhibit the expression of NF-κB p65, IκBα and up-regulate the expression of HO-1 and NRF2 more operatively to protect gastric mucosa through anti-inflammatory and antioxidant stress mechanisms.

CONCLUSION

Compared with rVR, pVR has an accelerated absorption in vivo and its effect time was prolonged, and the observed improvement of anti-AGMI effect was achieved through anti-oxidation and anti-inflammation regulation.

Pharmacological Effects and Toxicogenetic Impacts of Omeprazole: Genomic Instability and Cancer

Omeprazole (OME) is commonly used to treat gastrointestinal disorders. However, long-term use of OME can increase the risk of gastric cancer. We aimed to characterize the pharmacological effects of OME and to correlate its adverse effects and toxicogenetic risks to the genomic instability mechanisms and cancer-based on database reports. Thus, a search (till Aug 2019) was made in the PubMed, Scopus, and ScienceDirect with relevant keywords. Based on the study objective, we included 80 clinical reports, forty-six in vitro, and 76 in vivo studies. While controversial, the findings suggest that long-term use of OME (5 to 40 mg/kg) can induce genomic instability. On the other hand, OME-mediated protective effects are well reported and related to proton pump blockade and anti-inflammatory activity through an increase in gastric flow, anti-inflammatory markers (COX-2 and interleukins) and antiapoptotic markers (caspases and BCL-2), glycoprotein expression, and neutrophil infiltration reduction. The reported adverse and toxic effects, especially in clinical studies, were atrophic gastritis, cobalamin deficiencies, homeostasis disorders, polyp development, hepatotoxicity, cytotoxicity, and genotoxicity. This study highlights that OME may induce genomic instability and increase the risk of certain types of cancer. Therefore, adequate precautions should be taken, especially in its long-term therapeutic strategies and self-medication practices.

Ceftriaxone Attenuated Anxiety-Like Behavior and Enhanced Brain Glutamate Transport in Zebrafish Subjected to Alcohol Withdrawal

Chronic and/or excessive consumption of alcohol followed by reduced consumption or abstention can result in Alcohol Withdrawal Syndrome. A number of behavioral changes and neurological damage result from ethanol (EtOH) withdrawal. Ceftriaxone (Cef) modulates the activity of excitatory amino acid transporters by increasing their gene expression. Zebrafish are commonly used to study alcohol exposure. The aim of this study was to evaluate the influence of Cef (100 µM) on behavior patterns, glutamate transport activity, and oxidative stress in zebrafish brains subjected to EtOH (0.3% v/v) withdrawal. The exploratory tests using Novel tank showed that EtOH withdrawal promoted a decrease in the time spent and number of entries of in the bottom displaying an anxiety-like behavior. In contrast, treatment with Cef resulted in recovery of exploratory behavioral patterns. Ceftriaxone treatment resulted in increased glutamate uptake in zebrafish subjected to EtOH withdrawal. Furthermore, EtOH withdrawal increased reactive species, as determined using thiobarbituric acid and dichlorodihydrofluorescein assays. Treatment with Cef reversed these effects. Ceftriaxone promoted a significant reduction in brain sulfhydryl content in zebrafish subjected to EtOH withdrawal. Therefore, Cef treatment in conjunction with EtOH withdrawal induced anxiolytic-like effects due to possible neuromodulation of glutamatergic transporters, potentially through mitigation of oxidative stress.

Selenium Nanoparticles-Embedded Chitosan Microspheres and Their Effects Upon Alcohol-Induced Gastric Mucosal Injury in Rats: Rapid Preparation, Oral Delivery, and Gastroprotective Potential of Selenium Nanoparticles

Background

Selenium (Se) is an indispensable trace element required for animals and human beings, whereas Se-deficiency can accelerate the development of acute gastric injury induced by over-consumption of alcohol. Selenium nanoparticles (SeNPs), as a special Se-supplement with favorable properties and unique bioactivities, are expected to play a passive role in gastroprotection. To the best of our knowledge, the gastroprotective potential of SeNPs is unknown and also, a rapid preparation of orally stable SeNPs available for prospective commercial application in the clinic is needed. Thus, SeNPs-embedded chitosan microspheres (SeNPs-CM) were developed to deliver SeNPs, and their gastroprotective potential was evaluated.

Results

Herein, a rapid, eco-friendly and economic preparation process, composed of synthesis of SeNPs decorated by chitosan (CS), purification of CS-SeNPs by ultra-filtration (UF) and spray-drying of the purified CS-SeNPs, was introduced to prepare SeNPs-CM. The uniformly distributed SeNPs with a nanosize range of 60 nm were loaded into CS-microspheres, and they could be released from the microspheres in gastric conditions. In addition, SeNPs-CM were safer than selenite in terms of Se dose, with a LD₅₀ of around 8-fold of that of selenite, and it could efficiently enhance the Se retention in Se-deficient Wistar rats. Furthermore, SeNPs-CM pre-treatment might significantly attenuate the ethanol-induced gastric mucosal damage, based on histological evaluation. It might be partly attributed to the systematic antioxidant activities of SeNPs-CM, reflected by the reduction in lipid peroxidation, the augmentation in antioxidant enzymatic activity as well as decreasing aggressive nitric oxides (NO).

Conclusion

SeNPs-CM could be taken into consideration as a prospective Se-supplement for the oral delivery of SeNPs, with prominent gastroprotective effect against ethanol-induced mucosal injury.

The implication of the crosstalk of Nrf2 with NOXs, and HMGB1 in ethanol-induced gastric ulcer: Potential protective effect is afforded by Raspberry Ketone

Ethanol consumption is one of the common causative agents implicated in gastric ulcer development. Oxidative stress plays a major role in the induction and development of gastric ulceration. NADPH oxidases (NOXs) and Nuclear factor erythroid 2-related factor 2 (Nrf2) are key players in ethanol-induced ulcers. High-mobility group box 1 (HMGB1), a ubiquitous nuclear protein, mediates various inflammation functions. However, the role of HMGB1 in ethanol-induced gastric ulcer is not yet elucidated. Raspberry Ketone (RK) is a natural phenolic compound with antioxidant and anti-inflammatory properties. In the present study, absolute ethanol (7.5 ml/kg) was used to induce gastric ulceration in rats. Raspberry Ketone (RK) (50 mg/kg) was given orally one hour before the administration of absolute ethanol. Interestingly, ethanol-induced gastric ulcer was associated with Nrf2 downregulation, which was correlated with NOX-1, 2 NOX-4, and HMGB1 upregulation, and was significantly reversed by RK pre-treatment. RK pre-treatment provided 80% gastroprotection. Gastroprotective properties of RK were mediated via antioxidant, anti-inflammatory (suppression of NF-kB and tumor necrosis factor-α), and antiapoptotic activities (reduction of Bax/Bcl2 ratio). Gastroprotective properties of RK were confirmed by histopathological examination. In conclusion, this study is the first to provide evidence to the role of HMGB1 in ethanol-induced gastric ulcer, and the crosstalk of Nrf2, NOXs and HMGB1. It also demonstrates that RK represents a promising gastroprotective activity comparable to omeprazole.

Novel chitosan oligosaccharide-based nanoparticles for gastric mucosal administration of the phytochemical "apocynin"

Background: Apocynin (APO) is a bioactive phytochemical with prominent anti-inflammatory and anti-oxidant activities. Designing a nano-delivery system targeted to potentiate the gastric antiulcerogenic activity of APO has not been investigated yet. Chitosan oligosaccharide (COS) is a low molecular weight chitosan and its oral nanoparticulate system for potentiating the antiulcerogenic activity of the loaded APO has been described here. Methods: COS-nanoparticles (NPs) loaded with APO (using tripolyphosphate [TPP] as a cross-linker) were prepared by ionic gelation method and fully characterized. The chosen formula was extensively evaluated regarding in vitro release profile, kinetic analysis, and stability at refrigerated and room temperatures. Ultimately, the in vivo antiulcerogenic activity against ketoprofen (KP)-induced gastric ulceration in rats was assessed by macroscopic parameters including Paul's index and antiulcerogenic activity, histopathological examination, immunohistochemical (IHC) evaluation of cyclooxygenase-2 (COX-2) expression level in ulcerated gastric tissue, and biochemical measurement of oxidative stress markers and nitric oxide (NO) levels. Results: The selected NPs formula with COS (0.5 % w/v) and TPP (0.1% w/v) was the most appropriate one with drug entrapment efficiency percentage of 35.06%, particle size of 436.20 nm, zeta potential of +38.20 mV, and mucoadhesive strength of 51.22%. It exhibited a biphasic in vitro release pattern as well as high stability at refrigerated temperature for a 6-month storage period. APO-loaded COS-NPs provoked marvelous antiulcerogenic activity against KP-induced gastric ulceration in rats compared with free APO treated group, which was emphasized by histopathological, IHC, and biochemical studies. Conclusion: In conclusion, APO-loaded COS-NPs could be considered as a promising oral phytopharmaceutical nanoparticulate system for management of gastric ulceration.

Amelioration of Ethanol-Induced Gastric Ulcers in Rats Pretreated with Phycobiliproteins of Arthrospira (Spirulina) Maxima

Phycobiliproteins of Arthrospira (Spirulina) maxima have attracted attention because of their potential therapeutic antioxidant properties. The aim of this study was to assess the possible antiulcerogenic activity of these phycobiliproteins (ExPhy) against ethanol-induced gastric ulcers in rats. To explore the possible mechanisms of action, we examined antioxidant defense enzymes (e.g., catalase, superoxide dismutase, and glutathione peroxidase), as well as the level of lipid peroxidation (MDA) and the histopathological changes in the gastric mucosa. Intragastric administration of ExPhy (100, 200, and 400 mg/kg body weight) significantly lowered the ulcer index value compared to the ulcer control group (p < 0.05). The greatest protection was provided by the concentration of 400 mg/kg. The histological study supported the observed gastroprotective activity of ExPhy, showing a reduced inflammatory response. Moreover, the alcohol-induced decrease in stomach antioxidant enzyme activity found in the ulcer control group was prevented by ExPhy pretreatment. Furthermore, ExPhy reversed the ethanol-induced increase in lipid peroxidation. In summary, the antiulcerogenic potential of ExPhy may be due, at least in part, to its anti-oxidant and anti-inflammatory effects.

Microvascular NADPH oxidase in health and disease

The systemic and cerebral microcirculation contribute critically to regulation of local and global blood flow and perfusion pressure. Microvascular dysfunction, commonly seen in numerous cardiovascular pathologies, is associated with alterations in the oxidative environment including potentiated production of reactive oxygen species (ROS) and subsequent activation of redox signaling pathways. NADPH oxidases (Noxs) are a primary source of ROS in the vascular system and play a central role in cardiovascular health and disease. In this review, we focus on the roles of Noxs in ROS generation in resistance arterioles and capillaries, and summarize their contributions to microvascular physiology and pathophysiology in both systemic and cerebral microcirculation. In light of the accumulating evidence that Noxs are pivotal players in vascular dysfunction of resistance arterioles, selectively targeting Nox isozymes could emerge as a novel and effective therapeutic strategy for preventing and treating microvascular diseases.

N-acetylcysteine a possible protector against indomethacin-induced peptic ulcer: crosstalk between antioxidant, anti-inflammatory, and antiapoptotic mechanisms

This study investigated the gastroprotective effects of N-acetylcysteine (NAC) against indomethacin-induced gastric ulcer in rats. Ulceration was induced by a single oral administration of indomethacin (30 mg/kg). 50 male albino rats were allocated into 5 equal groups: control group received normal saline orally, indomethacin group rats received normal saline orally for 5 days and indomethacin (50 mg/kg) on the last day, ranitidine group received ranitidine (reference drug) orally for 5 days (50 mg/kg) before receiving indomethacin (50 mg/kg) on the last day, and NAC groups received NAC orally at 300 and 500 mg/kg, respectively, for 5 days before receiving indomethacin (50 mg/kg) on the last day. Gastric tissue interleukin-1β (IL-1β), interferon-γ (IFN-γ), and caspase-3 levels were immunoassayed. Total thiol (T-SH), myeloperoxidase (MPO), and glucose-6-phosphate dehydrogenase (G6PD) were determined by spectrophotometry. Cytokine-induced neutrophil chemoattractant 2α (CINC-2α) gene expression was evaluated in addition to Bcl-2 immunohistochemistry. Pretreatment with NAC improved the inflammatory, apoptotic, and redox status in a dose-dependent manner particularly in NAC 500 mg/kg pretreated group. These results show a role for NAC in improving indomethacin-induced gastric ulceration via antioxidative, antiapoptotic, and anti-inflammatory interactive mechanisms.

Anti-ulcerogenic effect of KFP-H008 against ethanol-induced gastric ulcer via p38 MAPK/NF-κB pathway

KFP-H008, a novel potassium-competitive acid blocker developed for the treatment of acid-related diseases, has been reported to inhibit gastric acid secretion effectively, while its effects on gastric ulcer have not been previously explored.

Protective Effects of Selenium, N-Acetylcysteine and Vitamin E Against Acute Ethanol Intoxication in Rats

The aim of this study was to determine possible protective influences of selenium (Se), N-acetylcysteine (NAC), and vitamin E (Vit E) against acute ethanol (EtOH) intoxication. Thirty-six rats were divided into six groups: I (control), II (EtOH), III (EtOH + Se), IV (EtOH + Vit E), V (EtOH + NAC), and VI (EtOH + mix). Except group I, EtOH was given the other pretreated (groups III, IV, V, and VI) and untreated groups (group II). Compared with the EtOH group, serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, creatine kinase, and creatine kinase-MB levels were significantly decreased in all pretreated groups, whereas slightly diminished amylase and lipase were observed. Compared with the control group, a remarkably lower total antioxidant status (TAS), but higher total oxidant status (TOS), and oxidative stress index (OSI) were seen in brain, liver, and kidney tissues. The values of these parameters were less affected from EtOH-exposed brain tissue of EtOH + NAC and liver of EtOH + mix groups. Both significant decrease of catalase activity and marked increases of adenosine deaminase and myeloperoxidase were determined only in liver tissue of the EtOH group. Activities of these enzymes were restored in almost all pretreated groups. Moreover, an increase of xanthine oxidase activity was prevented in brain tissue of pretreated groups. In histopathological examination of the liver, hydropic degeneration, sinusoidal dilatation, mononuclear cell infiltration, and marked congestion, which were seen in the EtOH group, were prevented in all pretreated groups. Relative protection against acute EtOH toxicity, in both single and combined pretreatments of Se, NAC, and Vit E supplementation, was probably through antioxidant and free radical-neutralizing effects of foregoing materials.

Gastroprotective effects of Kangfuxin-against ethanol-induced gastric ulcer via attenuating oxidative stress and ER stress in mice

Oxidative stress and ER stress play a role in the pathogenesis of gastric ulcer. Kangfuxin (KFX) has been used to treat gastric ulcer in patients. However, the underlying mechanisms of KFX action remain unclear. The current study was undertaken to evaluate the gastroprotective effects of KFX and to determine its potential mechanisms. Ethanol-induced gastric ulcer mouse model was employed. Ethanol pretreated mice were treated with low (0.02 g/kg) and high (0.05 g/kg) dose of KFX for 14 days. Cimetidine (0.8 g/kg) was used as positive control. Histological evaluation of the gastric mucosa revealed that mice treated with ethanol exhibited severe gastric mucosal damage. Ethanol treatment increased plasma and gastric MDA level, decreased plasma and gastric SOD activity, and reduced gastric HO-1 and GCL-c mRNA levels. ER stress markers (CHOP, GRP78, and caspase 12) were up-regulated upon ethanol administration. Moreover, increased cell apoptosis and pro-apoptotic protein Bax and caspase 3 were observed in ethanol treated mice, while the anti-apoptotic protein Bcl 2 was inhibited. Finally, KFX treatment reversed ethanol-induced phenotypes and ameliorated gastric ulcer. Our results demonstrated that the gastroprotective effects of KFX against ethanol-induced gastric ulcer could be attributed to its anti-oxidative stress, anti-ER stress and anti-apoptotic effects.