Phytochemicals enhance antioxidant enzyme expression to protect against NSAID-induced oxidative damage of the gastrointestinal mucosa

In Vitro Protective Effects of a Standardized Extract of Opuntia ficus-indica (L.) Mill. Cladodes and Olea europaea L. Leaves Against Indomethacin-Induced Intestinal Epithelial Cell Injury

Nonsteroidal anti-inflammatory drugs (NSAIDs) can induce serious adverse effects in gastrointestinal (GI) mucosa, increasing intestinal permeability and leading to mitochondrial dysfunction, oxidative stress, apoptosis and inflammation. As proton pump inhibitors are effective in protecting against NSAID-induced gastropathy but not NSAID-induced enteropathy, current research is focused on natural products as protective substances for therapy and prevention of intestinal injury. Herein, through the use of an in vitro model based on intestinal epithelial cell (Caco-2) damage caused by indomethacin (INDO), we examined the protective activity of a commercially available standardized extract (OFI+OE) from Opuntia ficus-indica (L.) Mill. cladodes and Olea europaea L. leaves. Pre-treatment with OFI+OE prevented INDO-induced intestinal epithelial barrier damage, as demonstrated by TEER measurement, fluorescein permeability, and tight junction protein expression. The extract showed positive effects against INDO-induced oxidative stress and correlated activation of apoptosis, decreasing pro-apoptotic markers BAX and Caspase-3 and increasing anti-apoptotic factor Bcl-2. Moreover, the extract inhibited the NF-κB pathway and pro-inflammatory cascade. In conclusion, these data support the use of OFI+OE extract as a natural strategy for therapy and prevention of intestinal mucosal damage, demonstrating its beneficial effects against INDO-induced intestinal damage, through modulation of oxidative, apoptotic, and inflammatory pathways.

Dietary Walnuts Prevented Indomethacin-Induced Gastric Damage via AP-1 Transcribed 15-PGDH, Nrf2-Mediated HO-1, and n-3 PUFA-Derived Resolvin E1

Non-steroidal anti-inflammatory drugs (NSAIDs), the most highly prescribed drugs in the world for the treatment of pain, inflammation, and fever, cause gastric mucosal damage, including ulcers, directly or indirectly, by which the development of GI-safer (-sparing) NSAIDs relates to unmet medical needs. This study aimed to document the preventive effects of walnut polyphenol extracts (WPEs) against NSAID-induced gastric damage along with the molecular mechanisms. RGM-1 gastric mucosal cells were administered with indomethacin, and the expressions of the inflammatory mediators between indomethacin alone or a combination with WPEs were compared. The expressions of the inflammatory mediators, including COX-1 and COX-2, prostaglandin E2, 15-hydroxyprostaglandin dehydrogenase (15-PGDH), and antioxidant capacity, were analyzed by Western blot analysis, RT-PCR, and ELISA, respectively. HO-1, Nrf-2, and keap1 were investigated. The in vivo animal models were followed with in vitro investigations. The NSAIDs increased the expression of COX-2 and decreased COX-1 and 15-PGDH, but the WPEs significantly attenuated the NSAID-induced COX-2 expression. Interestingly, the WPEs induced the expression of 15-PGDH. By using the deletion constructs of the 15-PGDH promoter, we found that c-Jun is the most essential determinant of the WPE-induced up-regulation of 15-PGDH expression. We confirmed that the knockdown of c-Jun abolished the ability of the WPEs to up-regulate the 15-PGDH expression. In addition, the WPEs significantly increased the HO-1 expression. The WPEs increased the nuclear translocation of Nrf2 by Keap-1 degradation, and silencing Nrf2 markedly reduced the WPE-induced HO-1 expression. We found that the WPE-induced HO-1 up-regulation was attenuated in the cells harboring the mutant Keap1, in which the cysteine 151 residue was replaced by serine. These in vitro findings were exactly validated in indomethacin-induced gastric rat models. Daily walnut intake can be a promising nutritional supplement providing potent anti-inflammatory, antioxidative, and mucosa-protective effects against NSAID-induced GI damage.

Use of Callistemon citrinus as a gastroprotective and anti-inflammatory agent on indomethacin-induced gastric ulcers in obese rats

Background

Obesity leads to an elevated risk of developing gastrointestinal disease such as gastric ulcers. Callistemon citrinus leaf extract has shown antioxidant, antimicrobial, hepatoprotective, and chemoprotective effects against colon cancer. The aim of this study is to evaluate the gastroprotective effect of C. citrinus leaf extract on indomethacin-induced gastric ulcers in obese rats.

Methods

Gastric ulcers were induced in female obese Wistar rats using a single oral dose of indomethacin (IND). In the first stage, the rats were fed with a high fat sugar diet (HFSD) for 15 weeks to induce obesity and, at the same time, the diet of the other group of animals included daily administration of ethanolic C. citrinus leaf extract (250 mg/kg) in addition to HFSD. In the second stage, gastric ulcers were induced with IND (30 mg/kg). The gastroprotective activity of C. citrinus, the inflammatory enzyme activities, and cytokines in the stomach were determined.

Results

C. citrinus produced a reduction of gastric lesions caused by IND. Myeloperoxidase (MPO), cyclooxygenase-2 (COX-2), and 5-lipoxygenase (5-LOX) activities also decreased. Although inflammatory biomarkers such as TNFα, IL-6, AOPP, and leptin were significantly decreased by C. citrinus, adiponectin levels increased. Moreover, C. citrinus decreased weight gain and morphological and biochemical parameters.

Conclusion

The use of indomethacin in rats fed with a high fat-sugar diet increased gastric ulcers. Gastroprotective effect of C. citrinus in obese rats is attributed to the reduction of pro-inflammatory cytokines and the inflammatory enzymes.

Plants with Anti-Ulcer Activity and Mechanism: A Review of Preclinical and Clinical Studies

Ulcer disorders including the oral mucosa, large intestine, and stomach mucosa, cause significant global health burdens. Conventional treatments such as non-steroid anti-inflammatory drugs (NSAIDs), proton pump inhibitors (PPIs), histamine H2 receptor antagonists (H2RAs), and cytoprotective agents have drawbacks like mucosal injury, diminish gastric acid secretion, and interact with concurrent medications. Therefore, alternative therapeutic approaches are needed to tackle this health concern. Plants are rich in active metabolites in the bark, roots, leaves, fruits, and seeds, and have been utilized for medicinal purposes since ancient times. The use of herbal therapy is crucial, and regulations are necessary to ensure the quality of products, particularly in randomized studies, to assess their efficacy and safety in treating ulcer disorders. This study aims to explore the anti-ulcer activity of medicinal plants in treating peptic ulcer disease, ulcerative colitis, and aphthous ulcers. Articles were searched in Scopus and PubMed, and filtered for publication from 2013 to 2023, resulting in a total of 460 from Scopus and 239 from PubMed. The articles were further screened by title and abstract and resulted in 55 articles. Natural products, rich in active metabolites, were described to manage ulcer disease by protecting the mucosa, reducing ulcer effects, inhibiting pro-inflammatory factors, and reducing bacterial load, thus improving patients' quality of life. Natural extracts have proven effective in managing other health problems, including ulcers by reducing pain and decreasing lesions. This review provides an overview of preclinical and clinical studies on medicinal plants, focusing on their effectiveness in treating conditions like peptic ulcers, ulcerative colitis, and aphthous ulcers.

Gingerol and/or sorafenib attenuates the DAB-induced HCC and hepatic portal vein dilatation via ATG4/CASP3 and COIIV/COX-2/NF-κB expression

Ginger (Gin) has numerous therapeutic properties. One of Gin's most potent components is 6-gingerol, a naturally occurring phenol. This study aimed to investigate the therapeutic impact of gingerol and/or sorafenib on the ATG4/CASP3 and COIIV/COX-2/NF-B Expression as a potential therapy for DAB-induced HCC. Gin was administered to HCC mice induced by p-Dimethylaminoazobenzene (DAB) alone or combined with sorafenib (Sor). Superoxide dismutase (SOD), catalase (CAT), and oxidative stress malondialdehyde (MDA), as well as biochemical markers including AST, ALT, ALP, Albumin, and Bilirubin, were examined. The expression of oncogenes (COIIV, COX-2, NF-κB, and survivin) and tumor suppressor genes (ATG4 and CASP3) was evaluated using qPCR. According to the results, the levels of MDA have been markedly decreased, while SOD and CAT have been increased. Further, the expression levels of tumor suppressor genes were upregulated, whereas the expression levels of oncogene genes were downregulated. Furthermore, in a dose-dependent manner, gingerol has shown the potential to alleviate hepatic portal vein (PV) dilatation and could offer a reliable therapy for HCC. This suggests combining the two compounds may be more effective than alone and that Gin could be a promising therapeutic option for HCC. The binding of Gin and Sor to the active sites of the target genes prevents them from functioning normally, which in turn stops the pathways from carrying out their oncogenic functions. Additionally, COX-2 inhibition reduces the production of certain pro-inflammatory compounds, which further averts oncogenesis. Conclusively, this study indicated that Gin has cytoprotective properties and anti-cancer activity that may be related to controlling oxidative stress. This effect may be achieved by suppressing the COIIV/COX-2/NF-κB pathway and upregulating the ATG4 /CASP3 pathways.

Natural Products as Dietary Agents for the Prevention and Mitigation of Oxidative Damage and Inflammation in the Intestinal Barrier

Food intake is a basic need to sustain life, but foodborne pathogens and food-related xenobiotics are also the main health concerns regarding intestinal barrier homeostasis. With a predominant role in the well-being of the entire human body, intestinal barrier homeostasis is strictly regulated by epithelial and immune cells. These cells are also the main intervenients in oxidative stress and inflammation-related diseases in the intestinal tract, triggered, for example, by genetic/epigenetic factors, food additives, pesticides, drugs, pathogens, and their metabolites. Nevertheless, the human diet can also be seen as a solution for the problem, mainly via the inclusion of functional foods or nutraceuticals that may act as antioxidant/anti-inflammatory agents to prevent and mitigate acute and chronic oxidative damage and inflammation. A literature analysis of recent advances in this topic highlights the significant role of Nrf2 (nuclear factor erythroid 2-related factor 2) and NF-kB (nuclear factor kappa-light-chain-enhancer of activated B cells) pathways in these biological processes, with many natural products and phytochemicals targeting endogenous antioxidant systems and cytokine production and balance. In this review, we summarized and discussed studies using in vitro and in vivo models of the intestinal tract used to reproduce oxidative damage and inflammatory events, as well as the role of natural products as modulators of Nrf2 and NK-kB pathways.

Xiaojianzhong decoction attenuates aspirin-induced gastric mucosal injury via the PI3K/AKT/mTOR/ULK1 and AMPK/ULK1 pathways

CONTEXT

Xiaojianzhong decoction (XJZD), classically prescribed in Chinese medicine, has protective and healing effects on gastric mucosal injury. However, the exact mechanism behind this effect remains unclear.

OBJECTIVE

To investigate the effect of XJZD on gastric mucosal injury and explore its underlying mechanisms.

MATERIALS AND METHODS

C57BL/6 mice were randomized into six groups (n = 10): the control group receiving sterile water, the model (aspirin 300 mg/kg), the XJZD high-dose (12 g/kg), XJZD medium-dose (6 g/kg), XJZD low-dose (3 g/kg) and omeprazole (20 mg/kg) groups, by gavage daily for 14 days. The area of gastric mucosal injury, mucosal injury index and degree of histopathological damage were analysed. Gastric mucosal epithelial cell apoptosis was detected. Epithelial cell autophagy was observed. The expression levels of tight junction proteins and proteins related to apoptosis, autophagy and the pentose phosphate pathway were analysed.

RESULTS

The results showed that after treatment with XJZD (12, 6 and 3 g/kg), the mucosal injury area was reduced (83.4%, 22.6% and 11.3%), the expression level of ZO-1 and occludin was up-regulated, the apoptosis rate of epithelial cells was reduced (40.8%, 25.4% and 8.7%), the expression of autophagy-related proteins LC3 and Beclin1 was decreased and the expression of p62 was increased, the PI3K/AKT/mTOR/ULK1(ser757) signalling pathway was activated, and the AMPK/ULK1(ser317) signalling pathway was inhibited. In addition, XJZD can antagonize the imbalance of redox homeostasis caused by aspirin and protect the gastric mucosa.

DISCUSSION AND CONCLUSIONS

XJZD protects against aspirin-induced gastric mucosal injury, implying it to be a potential therapeutic agent.

Tubuloside A, a phenylethanoid glycoside, alleviates diclofenac induced hepato-nephro oxidative injury via Nrf2/HO-1

The most prominent adverse effects of nonsteroidal anti-inflammatory drugs (NSAIDs) such as diclofenac (DF) are hepato-renal damage. Natural antioxidants can be preferred as an alternative and/or combination to improve this damage. This present study was conducted to evaluate the protective effect of Tubuloside A (TA) against diclofenac (DF)-induced hepato-renal damage. TA (1 mg/kg, ip) was administered to male Sprague-Dawley rats for 5 days, and DF (50 mg/kg, ip) was administered on Days 4 and 5. Plasma aspartate amino transferase, alanine amino transferase, alkaline phosphatase, blood urea nitrogen and creatinine were measured to evaluate liver and kidney functions. Additionally, oxidative stress parameters (malondialdehyde, glutathione, superoxide dismutase, catalase, and 8-oxo-7,8-dihydro-2'-deoxyguanosine) in blood, liver, and kidney tissues, changes in mRNA expression of genes involved in the Nrf2/HO-1 signalling pathway (Nrf2, HO-1, NQO-1, IL-6, iNOS, Cox-2, TNF-α, IL1-β and NFκB) and apoptotic process (Bcl-2, Cas-3 and Bax) in liver and kidney tissues were determined. Additionally, tissue sections were evaluated histopathologically. Biochemical, histopathological, and molecular results demonstrated the hepato-renal toxic effects of DF, and TA treatment protected the liver and kidney from DF-induced damage. This provides an explanation for the hepato-nephro damage caused by DF and offers new ideas and drug targets together with TA for the prevention and treatment of DF injury.

Flavonoid-Rich Sambucus nigra Berry Extract Enhances Nrf2/HO-1 Signaling Pathway Activation and Exerts Antiulcerative Effects In Vivo

Sambucus nigra (SN) berry extract is characterized by high antioxidant and anti-inflammatory activity. The current study aimed to investigate the effect of SN berry extract against indomethacin (IND)-induced gastric ulcer in rats and the mechanism involved. SN berry extract alleviated IND-induced gastric ulcers, as shown by assessing pathological manifestations in the gastric mucosa. These protective effects are attributed to attenuated oxidative damage to the gastric mucosa, correlated to increased activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), enhanced glutathione (GSH) levels, total antioxidant capacity (TAC), and upregulation of the Nrf2/HO-1 cascade. Moreover, oxidative stress markers, including malondialdehyde (MDA) and total oxidant status (TOS), were downregulated in SN-extract-treated animals. Furthermore, SN berry extract suppressed gastric mucosal inflammation by downregulating interleukin (IL)-33, IL-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) levels, and attenuating myeloperoxidase (MPO) activity. The protective effects of SN berry extract were similar to those exerted by esomeprazole (ESO), an acid-secretion-suppressive drug. In conclusion, SN berry extract has antiulcerative effects, alleviating oxidative stress and inflammation.

Effect of Annona squamosa leaf extract on human promyelocytic leukemia cells subjected to oxidative stress

OBJECTIVES

Annona squamosa has beneficial properties. However, its cytotoxicity and antioxidative effects on human promyelocytic leukemia cells (HL60) deserve investigation. Therefore, the efficacy of its crude extracts in offsetting damage in HL60 cells subjected to oxidative stress was studied.

METHODS

Crude extracts at different concentrations were incubated with HL60 cells. The beneficial properties of the plant extract against oxidative damage were evaluated post-induction of oxidative stress utilizing hydrogen peroxide.

RESULTS

Extracts at concentrations 600 and 800 μg/mL were most effective at increasing the viability of damaged cells compared to the control group after 48 h of incubation. Significant increases in lipid peroxidation were observed in exposed cells treated with 600 μg/mL extract after 72 h of incubation. Superoxide dismutase (SOD) and catalase activities significantly increased in exposed cells after 24 h of incubation at all extract concentrations. Exposed cells treated with 600 and 1,000 μg/dL of the extract showed significantly increased catalase activity after 48 h, and a similar profile was maintained after 72 h of exposure. SOD activity in exposed cells remained significantly increased at all treatment concentrations after 48 and 72 h of incubation. Treatment with 400, 600, and 800 μg/mL of the extract resulted in significantly increased reduced glutathione levels compared to the other groups after 24 and 72 h of incubation. However, after 48 h of incubation, significant increases were noted in glutathione levels in exposed cells incubated with either 400, 800, or 1,000 μg/mL extract.

CONCLUSIONS

The findings suggest that A. squamosa might effectively protect against oxidative damage in a time and extract concentration-dependent manner.

Anti-Alzheimer Activity of Combinations of Cocoa with Vinpocetine or Other Nutraceuticals in Rat Model: Modulation of Wnt3/β-Catenin/GSK-3β/Nrf2/HO-1 and PERK/CHOP/Bcl-2 Pathways

Alzheimer's disease (AD) is a devastating illness with limited therapeutic interventions. The aim of this study is to investigate the pathophysiological mechanisms underlying AD and explore the potential neuroprotective effects of cocoa, either alone or in combination with other nutraceuticals, in an animal model of aluminum-induced AD. Rats were divided into nine groups: control, aluminum chloride (AlCl3) alone, AlCl3 with cocoa alone, AlCl3 with vinpocetine (VIN), AlCl3 with epigallocatechin-3-gallate (EGCG), AlCl3 with coenzyme Q10 (CoQ10), AlCl3 with wheatgrass (WG), AlCl3 with vitamin (Vit) B complex, and AlCl3 with a combination of Vit C, Vit E, and selenium (Se). The animals were treated for five weeks, and we assessed behavioral, histopathological, and biochemical changes, focusing on oxidative stress, inflammation, Wnt/GSK-3β/β-catenin signaling, ER stress, autophagy, and apoptosis. AlCl3 administration induced oxidative stress, as evidenced by elevated levels of malondialdehyde (MDA) and downregulation of cellular antioxidants (Nrf2, HO-1, SOD, and TAC). AlCl3 also upregulated inflammatory biomarkers (TNF-α and IL-1β) and GSK-3β, leading to increased tau phosphorylation, decreased brain-derived neurotrophic factor (BDNF) expression, and downregulation of the Wnt/β-catenin pathway. Furthermore, AlCl3 intensified C/EBP, p-PERK, GRP-78, and CHOP, indicating sustained ER stress, and decreased Beclin-1 and anti-apoptotic B-cell lymphoma 2 (Bcl-2) expressions. These alterations contributed to the observed behavioral and histological changes in the AlCl3-induced AD model. Administration of cocoa, either alone or in combination with other nutraceuticals, particularly VIN or EGCG, demonstrated remarkable amelioration of all assessed parameters. The combination of cocoa with nutraceuticals attenuated the AD-mediated deterioration by modulating interrelated pathophysiological pathways, including inflammation, antioxidant responses, GSK-3β-Wnt/β-catenin signaling, ER stress, and apoptosis. These findings provide insights into the intricate pathogenesis of AD and highlight the neuroprotective effects of nutraceuticals through multiple signaling pathways.

Investigation of the phytochemical composition and remedial effects of southern grape hyacinth (Muscari neglectum Guss. ex Ten.) plant extract against carbon tetrachloride-induced oxidative stress in rats

We aimed to determine the phytochemical contents of the aerial part M. neglectum aerial part (MAP) and M. neglectum bulb (MB) ethanolic extract of Muscari neglectum and to investigate their protective effects on gastric damage induced by carbon tetrachloride (CCl₄) in rats. After the toxicity testing, 42 female Wistar albino rats were divided into 7 groups, Control, MAP, MB, CCl₄, CCl₄ + MAP, CCl₄ + MB, and CCl₄ + Silymarin groups. At the end of the experiment, the serum biochemical parameters, antioxidant defense enzymes, and malondialdehyde (MDA) contents in the stomach tissue were evaluated to determine the antioxidant role of the M. neglectum extracts. According to the gas chromatography-mass spectroscopy, fatty acid analysis, octadecadienoic, and 9,12,15 octadecatrienoic fatty acids were found as major fatty acids in the MAP, whereas 9,12 octadecadienoic and octadecanoic acids were the major fatty acids in the MB. According to the liquid chromatography-tandem mass spectrometry, quinic acid, fumaric acid, gentisic acid, caffeic acid, kaempferol, and apigenin were found in the MAP, while quinic acid, fumaric acid, caffeic acid, and kaempferol were found in the MB. The total phenolic and flavonoid contents in the extract were determined in the MAP and MB. The MAP and MB extracts generally caused a statistically significant decrease in the MDA content and increase in the antioxidant parameters in the stomach tissue. It was concluded that MAP and MB extracts may have antioxidant and gastric protective effects due to the phytochemical content of M. neglectum.HighlightsAccording to LC-MS/MS results, quinic acid, fumaric acid, chemferol, apigenin, and caffeic acid were determined as major compounds in M. neglectum extracts.According to GC-MS results, octadecadienoic, octadecatrienoic, and octadecanoic methyl esters were the major fatty acids of the M. neglectum extracts.The M. neglectum extracts regulated the levels of stomach damage and biochemical parameters.The M. neglectum extracts extract might have pharmaceutical-nutritional potential.

Gastroprotective effects of water extract of domesticated Amauroderma rugosum against several gastric ulcer models in rats

CONTEXT

Amauroderma rugosum (Blume & T. Nees) Torrend (Ganodermataceae) is an edible mushroom with medicinal properties. However, the effects of A. rugosum on gastric ulcer remain unclear.

OBJECTIVE

To investigate the gastroprotective efficacy of water extract of A. rugosum (WEA) on gastric ulcer.

MATERIALS AND METHODS

Sprague-Dawley rats were randomly grouped as control, model, lansoprazole and 200, 100 and 50 mg/kg of WEA. After pre-treatment for seven days, ethanol- and indomethacin-induced gastric ulcer models were established. The gastric ulcer and histopathology were investigated. Enzyme-linked immunosorbent assay (ELISA), quantitative polymerase chain reaction (Q-PCR) and Western blot assays were conducted to explore the potential anti-inflammatory effect and mechanism of WEA. Additionally, the pyloric ligation model was used to explore the influence of WEA on gastric acid and mucus.

RESULTS

Pre-treatment with WEA (200, 100 and 50 mg/kg) effectively reduced ulcerous area in both ethanol-induced (71%, 88% and 71%) and indomethacin-induced (77%, 65% and 86%) gastric ulcer model. The gastric levels of tumour necrosis factor-alpha (TNF-α) (34% and 50 mg/kg), interleukin-6 (IL-6) (32% and 100 mg/kg) and interleukin-1β (IL-1β) (36%, 45% and 41%) were reduced significantly (p < 0.05) by WEA. Serum nitric oxide was decreased significantly (p < 0.05) at 200 and 50 mg/kg and PGE2 concentration was increased remarkably (p < 0.05) at 100 mg/kg. Gene expression of inflammasome Nlrp3, and the nuclear translocation of nuclear factor-κB (NF-κB) P65 were significantly decreased by WEA pre-treatment. However, the pH of gastric acid and secretion of mucus did not show any significant change.

CONCLUSIONS

The gastroprotective effect of WEA on gastric damage is attributed to anti-inflammation through the inhibition on NF-κB P65 nuclear migration and Nlrp3 gene expression.

Tissue-Protective Mechanisms of Bioactive Phytochemicals in Flap Surgery

Despite careful preoperative planning, surgical flaps are prone to ischemic tissue damage and ischemia–reperfusion injury. The resulting wound breakdown and flap necrosis increase both treatment costs and patient morbidity. Hence, there is a need for strategies to promote flap survival and prevent ischemia-induced tissue damage. Phytochemicals, defined as non-essential, bioactive, and plant-derived molecules, are attractive candidates for perioperative treatment as they have little to no side effects and are well tolerated by most patients. Furthermore, they have been shown to exert beneficial combinations of pro-angiogenic, anti-inflammatory, anti-oxidant, and anti-apoptotic effects. This review provides an overview of bioactive phytochemicals that have been used to increase flap survival in preclinical animal models and discusses the underlying molecular and cellular mechanisms.

Malvidin Protects against and Repairs Peptic Ulcers in Mice by Alleviating Oxidative Stress and Inflammation

Peptic ulcer episodes cause damage to the stomach and intestine, with inflammatory cell infiltration and oxidative stress as the main players. In this study, we investigated the potential of anthocyanidin malvidin for preventive and curative peptic ulcer treatment. The anthocyanidin effects were examined in gastric ulcer mouse models induced by ethanol, non-steroidal anti-inflammatory drugs (NSAIDs), ischemia-reperfusion (IR), acetic acid and duodenal ulcer induced by polypharmacy. Expression levels of oxidative and inflammatory genes were measured to investigate the mechanism of anthocyanin activity. At a dose of 5 mg·kg⁻¹, Malvidin prevented gastric ulcer induction by ethanol, NSAID and repaired the tissue after 6 days of IR. Moreover, the anthocyanidin accelerated the healing of acetic acid-induced ulcer, increased the gene expression of EGF and COX-1, and downregulated MMP-9. Anthocyanin treatment mitigated the effect of polypharmacy on inflammation and oxidative stress observed in the intestine. Additionally, the compound downregulated cytokine expression and TLR4 and upregulated HMOX-1 and IL-10, exhibiting protective activity in the mouse gut. Malvidin thus prevented gastric and duodenal ulcers due to prominent anti-inflammatory and antioxidative effects on the gastrointestinal tract that were related to gene expression modulation and an increase in endogenous defense mechanisms.

Gastro-Protective Effects of Albizia anthelmintica Leaf Extract on Indomethacin-Induced Gastric Ulcer in Wistar Rats: In Silico and In Vivo Studies

We have previously reported that the leaf extract of Albizia anthelmintica exhibited substantial antioxidant, anti-inflammatory, analgesic, and antipyretic properties in vivo. We also comprehensively characterized the active phytoconstituents and found several flavonoids and galloyl glucosides derivatives. In the current work, we explored the gastroprotective effects of the leaf extract in an indomethacin-induced ulcer model and the mechanisms involved. The rats being pretreated with the tested extract (100 and 200 mg kg-1) significantly prevented gastric lesions by 87.4% and 92.3%, respectively, and they had no structural derangements in the gastric mucosa. The extract significantly reduced the elevated levels of IKκB, NF-κB, TNF-α, IL-6, iNOS, and lipid peroxidation; increased the reduced level of glutathione peroxidase (GPx) activity; and reduced glutathione (GSH) in the indomethacin-induced ulcer model. The protective activities of the extract were similar in most aspects to those exerted by the known anti-ulcer drug famotidine. These activities might be attributed to the anti-inflammatory and antioxidant activities, and the reduction of iNOS levels. In conclusion, Albizia anthelmintica is a potential candidate for management of gastric ulcers with antioxidant properties.

The Protective Roles of Butein on Indomethacin Induced Gastric Ulcer in Mice

Objective

Butein is a potential agent first isolated from Rhus verniciflua that has medicinal value in East Asia and has been used in the treatment of gastritis, gastric cancer, and atherosclerosis since ancient times. The aim of our study is to show, for the first time, the anti-ulcerative effect of butein in indomethacin induced gastric ulcer in mice.

Materials and Methods

A total of 42 mice were fasted 24 hours for the ulcer experiment, and 10, 20, and 40 mg/kg doses of butein were evaluated for their antiulcer activity. Famotidine 40 mg/kg was used as a positive control group. For ulcer induction, 25 mg/kg dose of indomethacin was administered to the mice and after 6 hours all stomachs were dissected out. After macroscopic analyses, tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), COX-1, and COX-2 mRNA levels of stomachs were evaluated by Real Time PCR, and Superoxide dismutase (SOD), glutathione (GSH), and malondialdehyde (MDA) were determined by ELISA.

Results

Butein administration exerted 50.8%, 65.9%, and 87.1% antiulcer effects at 10, 20, and 40 mg/kg, respectively. Butein administration decreased oxidative stress and inflammatory parameters in stomach tissues dose dependently. Furthermore, butein administration increased stomach PGE2 levels and decreased COX-1 and COX-2 mRNA levels.

Conclusion

Butein has been shown to have a healing effect on ulcers in macroscopic examinations in our study. We observed that butein has antioxidant and anti-cytokine properties in gastric tissue. Butein could be an important alternative in the treatment of indomethacin-induced ulcers. Whether butein is a partial agonist of the COX enzyme should be investigated in future studies.

Curcumin, a Natural Antimicrobial Agent with Strain-Specific Activity

Curcumin, a principal bioactive substance of turmeric (Curcuma longa L.), is reported as a strong antioxidant, anti-inflammatory, antibacterial, antifungal, and antiviral agent. However, its antimicrobial properties require further detailed investigations into clinical and multidrug-resistant (MDR) isolates. In this work, we tested curcumin's efficacy against over 100 strains of pathogens belonging to 19 species. This activity was determined by the broth microdilution method and by calculating the minimum inhibitory concentration (MIC). Our findings confirmed a much greater sensitivity of Gram-positive than Gram-negative bacteria. This study exhibited a significantly larger variation in the curcumin activity than previous works and suggested that numerous clinical strains of widespread pathogens have a poor sensitivity to curcumin. Similarly, the MICs of the MDR types of Staphylococcus aureus, S. haemolyticus, Escherichia coli, and Proteus mirabilis were high (≥2000 µg/mL). However, curcumin was effective against some species and strains: Streptococcus pyogenes (median MIC = 31.25 µg/mL), methicillin-sensitive S. aureus (250 µg/mL), Acinetobacter lwoffii (250 µg/mL), and individual strains of Enterococcus faecalis and Pseudomonas aeruginosa (62.5 µg/mL). The sensitivity of species was not associated with its affiliation to the genus, and it could differ a lot (e.g., S. pyogenes, S. agalactiae and A. lwoffii, A. baumannii). Hence, curcumin can be considered as a promising antibacterial agent, but with a very selective activity.

Chinese liquor extract attenuates oxidative damage in HepG2 cells and extends lifespan of Caenorhabditis elegans

Chinese liquor is obtained from various grains by fermentation and complex processes. Chinese liquor contains complex ingredients. However, the low contents and presence of ethanol restricted the flavor substances function study. In current study, a flavor substance, homofuraneol (HOMO) was isolated from the Chinese liquor and the potency against H2O2-induced oxidative damage in HepG2 cells and lifespan-extending ability in Caenorhabditis elegans were explored. Results indicated that HOMO increased the HepG2 cells cytoactive by eliminating excessive intracellular free radicals, upregulating antioxidant enzyme activity and inhibiting the phosphorylation of mitogen-activated protein kinases (MAPKs) pathway. Further study revealed that HOMO extended the lifespan of N2 nematodes under normal and oxidative stress conditions. Moreover, RT-PCR results showed that paraquat activated the expression of PMK-1 and SKN-1 was significantly regulated by HOMO. Of note, our results indicated that HOMO recovered the redox states of HepG2 cells by targeting MAPKs and upregulating the stress resistance of nematodes by modulating the expression of stress-responsive genes, such as DAF-16.

Particularities of Experimental Models Used to Induce Gastric Ulcer

Introduction: Gastric ulcer is one of the most common gastrointestinal diseases, therefore the constant interest for new treatments is due to adverse effects induced by current therapy. The restricted number of in vivo experimental models is a challenge for researchers. Objectives: Identifying the particularities of different types of experimentally induced gastric ulcer in laboratory animals to facilitate their choise for the study of new antiulcer drugs.

Material and method: A search in PubMed and Scopus using keywords ( “experimentally” AND “gastric ulcer” AND “rats/mice”) to include experimental studies with the description of local-induced changes. Review articles and in vitro studies were excluded.

Results and discussions: Experimental researches on new drugs for gastric ulcer use chemical or surgical methods to induce gastric lesions in rats. Non-steroidal anti-inflammatory drugs (NSAIDs) and acetic acid models to investigate antisecretory and cytoprotective effects; ethanol models evaluate cytoprotective and/or antioxidant effects; pylorus ligature models to evaluate the effects on the secretion of aggressive gastric factors (hydrochloric acid or pepsin). NSAIDs (indomethacin, acetylsalicylic acid or ibuprofen) inhibit cyclooxygenase activity, resulting from reduced mucus and bicarbonate secretion, decreased mucosal blood flow, alteration of microvascular structures, causing epithelial damage Ethanol enhances the proteolytic and hydrolytic action of hydrochloric acid and pepsin; in addition, stimulates the acid secretion and disruptes vascular endothelium. Pylorus ligature determines the accumulation of gastric acid resulting in gastric ulcers due to the autodigestion of the mucosa.

Conclusion: The knowledge of the mechanisms to induce experimental gastric ulcers is essential for choosing the model to evaluate new antiulcer agents.

Crocin exerts improving effects on indomethacin-induced small intestinal ulcer by antioxidant, anti-inflammatory and anti-apoptotic mechanisms

Crocin is a plant-derived carotenoid and bears potent antioxidant property. Ranitidine (a histamine H₂ receptor blocker) is used for peptic ulcer treatment. The present study was planned to investigate the effects of crocin and ranitidine on indomethacin-induced ulcer in small intestine of rats. Animals were randomized into two major groups including indo-methacin (10.00 mg kg^-1, ulcer group, 48 rats) and normal saline (1.00 mL kg^-1, intact group, 48 rats) groups. Each of these two major groups was subdivided into eight subgroups for intra-peritoneal (IP) injections of normal saline, crocin (2.50, 10.00 and 40.00 mg kg^-1), ranitidine (5.00 and 20.00 mg kg^-1), crocin (2.50 and 10.00 mg kg^-1) plus ranitidine (5.00 mg kg^-1). Indomethacin induced intestinal ulcer was characterized by bleeding, inflammation, epithelial hyperplasia and crypt loss. This non-steroidal anti-inflammatory drug (NSAID), indomethacin decreased goblet cell number and superoxide dismutase (SOD) activity and increased small intestine weight, organo-somatic index (OSI), malodealdehyde (MDA), tumor necrosis factor-α (TNF-α) and caspase-3 contents of intestine. Crocin resolved all the above-mentioned parameter changes induced by indomethacin. These treatments produced no significant effects on the above-mentioned parameters of intact group. The results of the present study showed tissue protective and anti-ulcer effects of crocin on small intestine by antioxidant, anti-inflammatory and anti-apoptotic mechanisms. Ranitidine alone showed no effect; however, in combination with crocin it exerted recovery effects. It is recommended that crocin, be considered as a therapeutic agent for NSAIDs-induced intestinal damage management.

Edaravone reduces oxidative stress and intestinal cell apoptosis after burn through up-regulating miR-320 expression

BACKGROUND

Intestinal mucosa barrier dysfunction after burn injury is an important factor for causing mortality of burn patients. The current study established a burn model in rats and used a free radical scavenger edaravone (ED) to treat the rats, so as to investigate the effect of edaravone on intestinal mucosa barrier after burn injury.

METHODS

Anesthetized rats were subjected to 40% total body surface area water burn immediately, followed by treatment with ED, scrambled antagomir, or antagomiR-320. Intestinal mucosa damage was observed by hematoxylin-eosin staining and graded by colon mucosal damage index (CMDI) score. The contents of total sulfhydryl (TSH), superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) were determined by spectrophotometry. Cell apoptosis, protein relative expression,and the in situ expressions of p-Akt and p-Bad were detected by flow cytometry, Western blotting and immunohistochemistry, respectively. The miR-320 expression was determined by quantitative real-time polymerase chain reaction.

RESULTS

ED alleviated intestinal mucosal damage caused by burn injury, down-regulated the levels of MDA, cytochrome C, cleaved caspase-9 and cleaved caspase-3, but up-regulated the levels of TSH, SOD, CAT and Bcl-2. We also found that ED could reduce oxidative stress, inhibit cell apoptosis, increase the expressions of p-Akt, p-Bad and miR-320, and decrease PTEN expression. PTEN was predicted to be the target gene for miR-320, and cell apoptosis could be promoted by inhibiting miR-320 expression.

CONCLUSION

ED regulates Akt/Bad/Caspase signaling cascade to reduce apoptosis and oxidative stress through up-regulating miR-320 expression and down-regulating PTEN expression, thus protecting the intestinal mucosal barrier of rats from burn injury.

Gastroprotective effects of Kangfuxin against water-immersion and restraint stress-induced gastric ulcer in rats: roles of antioxidation, anti-inflammation, and pro-survival

Context: Kangfuxin (KFX) is widely used for the treatment of gastric and duodenal ulcer; however, more research is needed to determine the protective mechanisms of KFX in ameliorating gastric ulcer.Objective: To investigate the efficacy and potential mechanism of Kangfuxin liquid (KFX) in water-immersion and restraint stress (WIRS)-induced gastric ulcer.Materials and methods: Seventy rats were randomly divided into seven groups (n = 10) as follows: the control group (normal saline, i.g.), the model group (normal saline, i.g.), the KFX groups (2.5, 5 and 10 mL/kg, i.g.), the omeprazole group (20 mg/kg, i.p.) and Sanjiuweitai Granules group (1850 mg/kg, i.g.). The WIRS model was applied to induce stress ulcers after 7 days of drug administration. Afterwards, rats were sacrificed at 10 h induced by WIRS.Results: Pre-treatment with KFX (5,10 mL/kg) could effectively reduce the area of gastric ulcers and improve the pathological changes of ulcerated tissue. Moreover, KFX (5,10 mL/kg) increased the prostaglandin E2 (52%) and cyclooxygenase-1 (30%) levels, and improved malondialdehyde (54%), superoxide dismutase (58%), catalase (39%), and nitric oxide (11%) and TNF-α (9%), IL-6 (11%), MMP-9 (54%) and MMP-2 (53%) of ulcer tissue. Furthermore, pre-treatment with KFX dramatically increased IGF-1, PTEN, and Akt protein expression.Conclusions: Our results suggest that KFX has protective effects on WIRS-induced gastric ulcer via inflammatory reactions, oxidative stress inhibition, and pro-survival action, which were the results of activating the IGF-1/PTEN/Akt signalling pathway. Our results provide evidence of KFX for treating gastric ulcer.

Protective effects of Ajwa date extract against tissue damage induced by acute diclofenac toxicity

Objectives

To investigate the tissue-protective effects of Ajwa date fruits (a Prophetic medicinal remedy) against acute diclofenac toxicity.

Methods

Albino Sprague–Dawley rats were allocated to four experimental groups: a negative control group, an Ajwa-only group that received 2 g/kg of Ajwa date extract (ADE) orally, an acute diclofenac toxicity group that received 200 mg diclofenac once intraperitoneally, and a treatment group that received diclofenac and ADE after 4 h. Histological examinations of rat lung and liver tissues were performed.

Results

Acute diclofenac toxicity caused marked hepatic derangements, such as congested central veins, congested blood sinusoids, hyaline degeneration, and hepatocyte necrosis. Toxic diclofenac overdose resulted in markedly congested alveolar capillaries and alveolar haemorrhages, thick edematous alveolar walls, and edema fluid exudates in the alveoli. Upon treatment with ADE, significant reduction in diclofenac-induced hepatic and pulmonary derangements were observed.

Conclusion

ADE is a safe, tissue-protective nutritional agent that alleviates cellular and tissue-damaging effects due to acute diclofenac toxicity. ADE relieved hepatic and pulmonary changes induced by acute diclofenac toxicity. The use of ADE is recommended for the treatment of acute diclofenac toxicity.

Curcumin: A Potent Protectant against Esophageal and Gastric Disorders

Turmeric obtained from the rhizomes of Curcuma longa has been used in the prevention and treatment of many diseases since the ancient times. Curcumin is the principal polyphenol isolated from turmeric, which exhibits anti-inflammatory, antioxidant, antiapoptotic, antitumor, and antimetastatic activities. The existing evidence indicates that curcumin can exert a wide range of beneficial pleiotropic properties in the gastrointestinal tract, such as protection against reflux esophagitis, Barrett's esophagus, and gastric mucosal damage induced by nonsteroidal anti-inflammatory drugs (NSAIDs) and necrotizing agents. The role of curcumin as an adjuvant in the treatment of a Helicobacter pylori infection in experimental animals and humans has recently been proposed. The evidence that this turmeric derivative inhibits the invasion and proliferation of gastric cancer cells is encouraging and warrants further experimental and clinical studies with newer formulations to support the inclusion of curcumin in cancer therapy regimens. This review was designed to analyze the existing data from in vitro and in vivo animal and human studies in order to highlight the mechanisms of therapeutic efficacy of curcumin in the protection and ulcer healing of the upper gastrointestinal tract, with a major focus on addressing the protection of the esophagus and stomach by this emerging compound.

Mechanisms underlying the acute toxicity of fullerene to Daphnia magna: Energy acquisition restriction and oxidative stress

The toxicity of fullerene (C₆₀) to Daphnia magna has been a subject with increasing concerns. Nevertheless, the underlying mechanisms are still poorly understood. In the present study, we evaluated various aspects of the toxicological impacts of C₆₀ on daphnia. After a 72-h exposure, the 50% effective concentration of C₆₀ was 14.9 mg/L for immobilization, and 16.3 mg/L for mortality. Daphnia exhibited a quick uptake of C₆₀ with a body burden value of 413 μg/g in wet weight in the 1 mg/L C₆₀ treatment group. Transmission electron microscopy observations revealed that C₆₀ had mainly accumulated in the guts of organisms. The feeding rate, gut ultra-structural alterations, and digestive enzyme activities of daphnia in response to C₆₀ treatment were evaluated. The results revealed a significant reduction in the digestion and filtration rates, as well as gut impairment and inhibition of digestive enzymes (cellulose, amylase, trypsin, and β-galactosidase) activity of C₆₀ exposed daphnia. In addition, the changes in superoxide dismutase (SOD) and malondialdehyde (MDA) levels in daphnia under C₆₀ exposures were also discovered. These results, for the first time, provide systematic evidence that C₆₀ caused a restriction in energy acquisition and increased oxidative damage in daphnia, which might be related to the bioaccumulation of C₆₀ and finally led to the immobility and mortality.