(-)-Myrtenol accelerates healing of acetic acid-induced gastric ulcers in rats and in human gastric adenocarcinoma cells

Exploring the Underlying Mechanisms of Preventive Treatment Related to Dietary Factors for Gastric Diseases

Gastric diseases have emerged as one of the main chronic diseases in humans, leading to considerable health, social, and economic burdens. As a result, using food or "food and medicinal homologous substances" has become an effective strategy to prevent gastric diseases. Diet may play a crucial role in the prevention and mitigation of gastric diseases, particularly long-term and regular intake of specific dietary components that have a protective effect on the stomach. These key components, extracted from food, include polysaccharides, alkaloids, terpenoids, polyphenols, peptides, probiotics, etc. The related mechanisms involve regulating gastric acid secretion, protecting gastric mucosa, increasing the release of gastric defense factors, decreasing the level of inflammatory factors, inhibiting Helicobacter pylori infection, producing antioxidant effects or reducing oxidative damage, preventing gastric oxidative stress by inhibiting lipid peroxides, activating Nrf2 signaling pathway, and inhibiting NF-κB, TLR4, and NOS/NO signaling pathways.

(-)-Fenchone Prevents Cysteamine-Induced Duodenal Ulcers and Accelerates Healing Promoting Re-Epithelialization of Gastric Ulcers in Rats via Antioxidant and Immunomodulatory Mechanisms

BACKGROUND

(-)-Fenchone is a naturally occurring monoterpene found in the essential oils of Foeniculum vulgare Mill., Thuja occidentalis L., and Peumus boldus Molina. Pharmacological studies have reported its antinociceptive, antimicrobial, anti-inflammatory, antidiarrheal, and antioxidant activities.

METHODS

The preventive antiulcer effects of (-)-Fenchone were assessed through oral pretreatment in cysteamine-induced duodenal lesion models. Gastric healing, the underlying mechanisms, and toxicity after repeated doses were evaluated using the acetic acid-induced gastric ulcer rat model with oral treatment administered for 14 days.

RESULTS

In the cysteamine-induced duodenal ulcer model, fenchone (37.5-300 mg/kg) significantly decreased the ulcer area and prevented lesion formation. In the acetic acid-induced ulcer model, fenchone (150 mg/kg) reduced (p < 0.001) ulcerative injury. These effects were associated with increased levels of reduced glutathione (GSH), superoxide dismutase (SOD), interleukin (IL)-10, and transforming growth factor-beta (TGF-β). Furthermore, treatment with (-)-Fenchone (150 mg/kg) significantly reduced (p < 0.001) malondialdehyde (MDA), myeloperoxidase (MPO), interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), and nuclear transcription factor kappa B (NF-κB). A 14-day oral toxicity investigation revealed no alterations in heart, liver, spleen, or kidney weight, nor in the biochemical and hematological parameters assessed. (-)-Fenchone protected animals from body weight loss while maintaining feed and water intake.

CONCLUSION

(-)-Fenchone exhibits low toxicity, prevents duodenal ulcers, and enhances gastric healing activities. Antioxidant and immunomodulatory properties appear to be involved in its therapeutic effects.

Protective role of fruits of Rosa odorata var. gigantea against WIRS-induced gastric mucosal injury in rats by modulating pathway related to inflammation, oxidative stress and apoptosis

Objective

Rosa odorata var. gigantea is a popular medicinal plant. Some studies have demonstrated that ethanolic extract of the fruits of R. odorata var. gigantea (FOE) has gastroprotective properties. The aim of this study was to investigate the gastroprotective activity of FOE on water immersion restrained stress (WIRS)-induced gastric mucosal injury in a rat model and elucidate the possible molecular mechanisms involved.

Methods

A rat stress ulcer model was established in this study using WIRS. After rats were treated with FOE orally for 7 d, the effect of FOE treatment was analyzed by hematoxylin and eosin (H&E) staining, and the changes of inflammatory factors, oxidative stress factors, and gastric-specific regulatory factors and pepsin in the blood and gastric tissues of rats were examined by ELISA assay. Molecular mechanism of FOE was investigated by immunohistochemical assay and Western blot.

Results

Compared with the WIRS group, FOE could diminish both the macroscopic and microscopic pathological morphology of gastric mucosa. FOE significantly preserved the antioxidants glutathione peroxidase (GSH-PX), superoxide dismutase (SOD) and catalase (CAT) contents; anti-inflammatory cytokines interleukin-10 (IL-10) and prostaglandin E2 (PGE2) levels as well as regulatory factors tumor necrosis factor-α (TGF-α) and somatostatin (SS) contents, while decreasing malondialdehyde (MDA), nitric oxide synthase (iNOS), tumor necrosis factor (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), gastrin (GAS) and endothelin (ET) levels. Moreover, FOE distinctly upregulated the expression of Nrf2, HO-1, Bcl2 and proliferating cell nuclear antigen (PCNA). In addition, FOE activated the expression of p-EGFR and downregulated the expression of NF-κB, Bax, Cleaved-caspase-3, Cyto-C and Cleaved-PARP1, thus promoting gastric mucosal cell survival.

Conclusion

The current work demonstrated that FOE exerted a gastroprotective activity against gastric mucosal injury induced by WIRS. The underlying mechanism might be associated with the improvement of anti-inflammatory, anti-oxidation and anti-apoptosis systems.

Sonchus oleraceus L. Promotes Gastroprotection in Rodents via Antioxidant, Anti-Inflammatory, and Antisecretory Activities

Sonchus oleraceus L. is an edible and medicinal plant used to treat stomachache and gastric ailments around the world. Thus, this study aimed to determine the gastroprotective mode of action of hydroalcoholic extract of S. oleraceus (HES). Mice were treated with HES before induction of gastric ulceration by ethanol/HCl. The area and histological appearance of ulcers were quantified, and mucus was measured histochemically. The effects of HES on inflammatory and oxidative markers were assessed in the ulcerated tissue. In addition, we investigated the gastric acid antisecretory activity of HES in pylorus-ligated rats. Chemical analyses of HES and its antioxidant activity were also performed in vitro. The HES (30 or 300 mg/kg) reduced the ulceration by 71.5 and 76.2%, respectively, compared with vehicle (p < 0.001), and the histological analysis confirmed the macroscopic results with elevation in mucin levels by 361.4 and 477.5%, respectively, compared with vehicle (p < 0.001). Moreover, the gastroprotection was accompanied by increases in GSH levels and in SOD, CAT, and GST activities; in parallel to a reduction in MPO activity and TNF levels. Furthermore, HES reduced the total acidity, and pepsin activity of the gastric juice of rats by 61 and 63%, respectively, compared to the vehicle. Phytochemical analysis indicated that luteolin-7-O-β-D-glucoside is the main active compound annotated in HES. Was also found that HES scavenged the DPPH radical with an IC₅₀ of 15.41 μg/mL. In conclusion, the gastroprotective effects of HES involve reductions in oxidative stress and inflammatory injury, in conjunction with an increase in mucus layer and inhibition of gastric secretion. This study advances in elucidating the modes of the antiulcer potential of S. oleraceus and contributes to the prospection of new gastroprotective molecules.

Myrtenol Reduces Orofacial Nociception and Inflammation in Mice Through p38-MAPK and Cytokine Inhibition

Orofacial pain is one of the commonest and most complex complaints in dentistry, greatly impairing life quality. Preclinical studies using monoterpenes have shown pharmacological potential to treat painful conditions, but the reports of the effects of myrtenol on orofacial pain and inflammation are scarce. The aim of this study was to evaluate the effect of myrtenol in experimental models of orofacial pain and inflammation. Orofacial nociceptive behavior and the immunoreactivity of the phosphorylated p38 (P-p38)-MAPK in trigeminal ganglia (TG) and spinal trigeminal subnucleus caudalis (STSC) were determined after the injection of formalin in the upper lip of male Swiss mice pretreated with myrtenol (12.5 and 25 mg/kg, i.p.) or vehicle. Orofacial inflammation was induced by the injection of carrageenan (CGN) in the masseter muscle of mice pretreated with myrtenol (25 and 50 mg/kg, i.p.) or its vehicle (0.02% Tween 80 in saline). Myeloperoxidase (MPO) activity and histopathological changes in the masseter muscle and interleukin (IL)-1β levels in the TG and STSC were measured. The increase in face-rubbing behavior time induced by formalin and P-p38-MAPK immunostaining in trigeminal ganglia were significantly reduced by myrtenol treatment (12.5 and 25 mg/kg). Likewise, increased MPO activity and inflammatory histological scores in masseter muscle, as well as augmented levels of IL-1β in the TG AND STSC, observed after CGN injection, were significantly decreased by myrtenol (25 and 50 mg/kg). Myrtenol has potential to treat orofacial inflammation and pain, which is partially related to IL-1β levels in the trigeminal pathway and p38-MAPK modulation in trigeminal ganglia.

Myrtenol improves brain damage and promotes angiogenesis in rats with cerebral infarction by activating the ERK1/2 signalling pathway

CONTEXT

Cerebral ischaemia/reperfusion (I/R) injury has a high disability and fatality worldwide. Myrtenol has protective effects on myocardial I/R injury through antioxidant and anti-apoptotic effects.

OBJECTIVE

This study investigated the effect of myrtenol on cerebral ischaemia/reperfusion (I/R) injury and the underlying mechanism.

MATERIALS AND METHODS

Cerebral I/R injury was induced in adult Sprague-Dawley rats by middle cerebral artery occlusion (MCAO) for 90 min. MCAO rats were treated with or without myrtenol (10, 30, or 50 mg/kg/day) or/and U0126 (10 μL) intraperitoneally for 7 days.

RESULTS

In the present study, myrtenol had no toxicity at concentrations up to 1.3 g/kg. Myrtenol treatment improved neurological function of MCAO rats, with significantly (p < 0.05) improved neurological deficits (4.31 ± 1.29 vs. 0.00) and reduced brain edoema (78.95 ± 2.27% vs. 85.48 ± 1.24%). Myrtenol extenuated brain tissue injury and neuronal apoptosis, with increased Bcl-2 expression (0.48-fold) and decreased Bax expression (2.02-fold) and caspase-3 activity (1.36-fold). Myrtenol promoted angiogenesis in the brain tissues of MCAO rats, which was reflected by increased VEGF (0.86-fold) and FGF2 (0.51-fold). Myrtenol promoted the phosphorylation of MEK1/2 (0.80-fold) and ERK1/2 (0.97-fold) in MCAO rats. U0126, the inhibitor of ERK1/2 pathway, reversed the protective effects of myrtenol on brain tissue damage and angiogenesis in MCAO rats.

DISCUSSION AND CONCLUSIONS

Myrtenol reduced brain damage and angiogenesis through activating the ERK1/2 signalling pathway, which may provide a novel alternative strategy for preventing cerebral I/R injury. Further in vitro work detailing its mechanism-of-action for improving ischaemic cerebral infarction is needed.

The essential oil from Baccharis trimera (Less.) DC improves gastric ulcer healing in rats through modulation of VEGF and MMP-2 activity

ETHNOPHARMACOLOGICAL RELEVANCE

Baccharis trimera (Less.) DC known as "carqueja" in Brazil has been acknowledged as a medicinal plant in folk medicine for the treatment of stomach aches and gastrointestinal disorders.

AIM OF THE STUDY

The present study aimed to evaluate the gastroprotective and healing effects of essential oil from B. trimera (EOBT) against gastric ulcer lesions caused by absolute ethanol and acetic acid, respectively, and to identify the mechanism of action of this essential oil in male Wistar rats.

MATERIALS AND METHODS

The plant material used to obtain EOBT was collected in the southern region of Brazil and was analyzed by chromatography-mass spectrometry (GCMS) demonstrate its characteristic chemical composition, with carquejyl acetate as its main component. Different doses of EOBT (50, 100, and 200 mg/kg) were administered orally in male Wistar rats as an acute treatment against absolute ethanol-induced gastric lesions. The gastric healing effect of EOBT (100 mg/kg) was evaluated once a day after 7, 10, and 14 days of treatment. After treatment, the stomachs of rats from all groups were collected to measure the lesion area (mm2), the activity of myeloperoxidase (MPO), and the relative expression of caspases -3, -8, -9, cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF). The zymography method was used to elucidate the activity of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) in the healing action of EOBT. We also analyzed toxicological parameters (body weight evolution and biochemical parameters) that could result after treatment with this essential oil for 14 days.

RESULTS

Pretreatment with EOBT (100 and 200 mg/kg) significantly decreased the severity of gastric damage induced by absolute ethanol and decreased MPO activity in gastric tissue. After 10 and 14 days of treatment with EOBT (100 mg/kg) once a day, the lesion area was significantly reduced by 61% and 65.5%, respectively, compared to the negative control group. The gastric healing effect of EOBT was followed by a decrease in the expression of COX-1 compared to that in the negative control group. Notably, treatment with EOBT for 14 days increased the expression of VEGF compared to that using an anti-ulcer drug (lansoprazole). Additionally, analyses of MMP-2 and MMP-9 activities in the gastric mucosa confirmed the accelerated gastric healing effect of EOBT, with a significant decrease in the activity of pro-MMP-2. No sign of toxicity was observed after treatment with EOBT for 14 consecutive days.

CONCLUSION

These findings indicated that EOBT was effective in preventing and accelerating ulcer healing by decreasing MPO activity, increasing VEGF expression, and decreasing MMP-2 activity. These actions collectively contribute to the rapid recovery of gastric mucosa following treatment with EOBT, without any observed toxicity.

Antibiofilm and antivirulence efficacy of myrtenol enhances the antibiotic susceptibility of Acinetobacter baumannii

Acinetobacter baumannii (AB) is rising as a human pathogen of critical priority worldwide as it is the leading cause of chronic opportunistic infections in healthcare settings and the condition is ineradicable with antibiotic therapy. AB possesses the ability to form biofilm on abiotic as well as biotic surfaces which plays a major role in its pathogenesis and resistance in clinical settings. Hence, the demand for an alternative therapy to combat the biofilm-associated infections is increasing. The present study explored the antibiofilm potential of myrtenol, a bicyclic monoterpene present in various plants against reference and clinical strains of AB. Myrtenol (200 μg/mL) exhibited a strong antibiofilm activity without exerting any harmful effect on growth and metabolic viability of AB strains. Microscopic analyses confirmed the reduction in the biofilm thickness and surface coverage upon myrtenol treatment. Especially, myrtenol was found to be effective in disrupting the mature biofilms of tested AB strains. Furthermore, myrtenol inhibited the biofilm-associated virulence factors of AB strains such as extracellular polysaccharide, cell surface hydrophobicity, oxidant resistance, swarming and twitching motility. Transcriptional analysis unveiled the suppression of the biofilm-associated genes such as bfmR, csuA/B, bap, ompA, pgaA, pgaC, and katE by myrtenol. Notably, myrtenol improved the susceptibility of AB strains towards conventional antibiotics such as amikacin, ciprofloxacin, gentamicin and trimethoprim. Thus, the present study demonstrates the therapeutic potential of myrtenol against biofilm-associated infections of AB.

EGFR-conjugated hydrogel accelerates wound healing on ulcer-induced burn wounds by targeting collagen and inflammatory cells using photoimmunomodulatory inhibition

In the present study, we fabricated an epidermal growth factor receptor (EGFR)-conjugated hydrogel to promote wound healing in cold restraint-induced gastric ulceration on burn wounds targeting collagen and inflammatory cells for the treatment of burns and gastric ulcers. Cytotoxicity and cell proliferation assays demonstrated good biocompatibility of hydrogel as a suitable extracellular matrix for targeted cells and support for regenerative cell growth. These findings were confirmed by staining methods. In vitro wound healing was confirmed cell migration in the targeted cells. The effect of the EGFR-H was investigated in cold restraint-induced gastric ulcers in rats, where the treatment was started immediately after ulcer induction. In the in vivo experiment, the EGFR-H demonstrated enhanced ulcer healing ability and less scarring compared to the hydrogel alone and controls. Thus, EGFR-H promotes healing of cold restraint-induced gastric ulcer via EGFR conjugated with a hydrogel. The present study demonstrates a novel pathway to fabricate hydrogels as suitable wound dressing biomaterials to improve deep partial thickness burn wound healing and prevent scar formation when aided by laser therapy.

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.

Role of Daucus carota in Enhancing Antiulcer Profile of Pantoprazole in Experimental Animals

The carrot plant (Daucus carota) and its components are traditionally reported for the management of gastric ulcers. This study was performed to evaluate the role of carrot when administered concurrently with a conventional antiulcer treatment, pantoprazole, in alleviating gastric and duodenal ulcers in female experimental animals. The study involved standard animal models to determine the ulcer preventive effect using pylorus ligation, ethanol, and stress induced acute gastric ulcer models and duodenal ulcer models involving cysteamine. Acetic acid-induced chronic gastric ulcer and indomethacin-induced gastric ulcer models were used to evaluate the ulcer healing effect. Carrot fruit (500 mg/kg) and its co-administration with pantoprazole produced significant protection in an ethanol- and stress-induced acute gastric ulcer and cysteamine-induced duodenal ulcer. The healing of the acetic acid-induced chronic gastric ulcer was also augmented with this combination. Both total proteins and mucin contents were significantly increased in indomethacin-induced gastric ulcers. Similarly, in pylorus ligation, the pepsin content of gastric juice, total acidity, and free acidity were reduced. Overall, both ulcer preventive effects and ulcer healing properties of the pantoprazole were significantly enhanced in animals who received the co-administration of carrot fruit (500 mg/kg).

Cenostigma macrophyllum Tul. var. acuminata Teles Freire Fraction Leaves Stimulate Gastric Healing in Rats and Human Cell Cultures

Cenostigma macrophyllum Tul. var. acuminata Teles Freire (Leguminosae-Caesalpinioideae) is a medicinal plant traditionally used for treatment of gastric ulcer. This study evaluated the ulcer-healing activity of the hydroalcoholic fraction of C. macrophyllum Tul. var. acuminata Teles Freire leaves (Cm-FHA) and the tea of the leaves of C. macrophyllum (Cm-tea), as well as the possible action of Cm-FHA, through in vitro models. Leaves of C. macrophyllum were dried and powdered to obtain the Cm-FHA. Subsequently, the Cm-FHA was characterized phytochemically and biologically. Besides, Cm-tea was prepared. The gastric healing effects of Cm-tea and Cm-FHA were analyzed using the model of acetic acid-induced gastric ulcer in rats. The human gastric adenocarcinoma (AGS) cell line was employed as an in vitro model. Cm-tea promoted a protective effect against gastric ulcers induced by absolute ethanol. Cm-FHA or Cm-tea (100 mg/kg/7 days) exhibited a significant healing effect on ulcers induced by acetic acid. In the histological analysis, gastric mucosa treated with Cm-FHA or Cm-tea advanced restoration of the mucosal epithelium. In vitro, lower concentrations of Cm-FHA stimulated cell proliferation in the BrdU assay and cell migration. Cm-tea and Cm-FHA present a significant gastric healing effect in in vivo and in vitro models.

Mutagenesis and Adaptation of the Psychrotrophic Fungus Chrysosporium pannorum A-1 as a Method for Improving β-pinene Bioconversion

Mutagenesis and adaptation of the psychrotrophic fungus Chrysosporium pannorum A-1 to the toxic substrate β-pinene were used to obtain a biocatalyst with increased resistance to this terpene and improved bioconversion properties. Mutants of the parental strain were induced with UV light and N-methyl-N'-nitro-N-nitrosoguanidine. Mutants resistant to β-pinene were isolated using agar plates with a linear gradient of substrate concentrations. Active mutants were selected based on their general metabolic activity (GMA) expressed as oxygen consumption rate. Compared to the parental strain, the most active mutant showed an enhanced biotransformation ability to convert β-pinene to trans-pinocarveol (315 mg per g of dry mycelium), a 4.3-fold greater biocatalytic activity, and a higher resistance to H2O2-induced oxidative stress. Biotransformation using adapted mutants yielded twice as much trans-pinocarveol as the reaction catalyzed by non-adapted mutants. The results indicate that mutagenesis and adaptation of C. pannorum A-1 is an effective method of enhancing β-bioconversion of terpenes.

Human-like collagen promotes the healing of acetic acid-induced gastric ulcers in rats by regulating NOS and growth factors

Human-like collagen (HLC), the collagen produced using fermentation technology, has been demonstrated previously to promote wound healing. However, the healing property of HLC in gastric ulcers remains to be verified. In this study, we investigated the healing efficacy and healing mechanisms of HLC on gastric ulcers. To investigate whether HLC still has healing activity on gastric ulcers after gastric digestion, we simulated gastric digestion in vitro to obtain a human-like collagen digestion product (HLCP) and used it as the control drug. A chronic gastric ulcer model induced by 60% acetic acid in rats was used to evaluate the healing effect of gastric ulcers in this study. The results showed that oral administration of HLC or HLCP for 4 or 7 days promoted ulcer healing, which can be directly observed by significant reductions in ulcer area. The oral administration of HLC and HLCP significantly increased the protein expression of growth factors (EGF, HGF, VEGF, bFGF and TGF-β1) and the HGF receptor (HGFr), promoted collagen deposition, regulated the activity of NOS, and decreased pro-inflammatory cytokines (TNF-a, il-6, il-10) and endothelin-1 (ET-1) levels in gastric tissue. Moreover, cell experiments showed that the effects of HLC on cell proliferation and migration are mainly caused by its digestion products. These findings indicate that HLC may be used as a nutritional supplement or therapeutic drug to promote the healing of gastric ulcers.

Girinimbine from curry leaves promotes gastro protection against ethanol induced peptic ulcers and improves healing via regulation of anti-inflammatory and antioxidant mechanisms

Curry leaves (Murraya koenigii) are a leafy spice used in Indian cookery for its fragrant aroma. Many bioactive functional compounds have been identified, and among them carbazole alkaloids have attracted wide attention due to their multi-dimensional medicinal value. Even though it has been established that the carbazole alkaloid is responsible for the anti-ulcer effect showed by this culinary herb, there is no further evidence to say which phytochemical is responsible for this. In the present study, we investigated the gastro-protective effects and mechanism of girinimbine, a major carbazole alkaloid present in curry leaves. Rats were administered with ethanol to produce gastric ulcers, and the prophylactic effect of girinimbine was evaluated. A macroscopic and histological examination was carried out to examine the lesions. Furthermore, the mucus production, NO production, PGE2 synthesis, mucosal nonprotein sulphydryls, glutathione (GSH) level, lipid peroxidation (MDA) level and COX inhibition were assessed. In addition, in particular, TNF-α and IL-6, two important cytokines, were evaluated. Immunohistochemical and gene expression studies were conducted to determine the HSP70 and iNOS biomarkers. Our results indicated that girinimbine significantly reduced the ulcer index and totally safeguarded the mucosa from lesions. The protective effect of girinimbine was complemented through the restoration of the reduced GSH and NP-SH level. This was associated with a reduction of MDA, which was elevated by the administration of ethanol. Pre-treatment of the ethanol induced ulcer with girinimbine reduced the NO concentration in the plasma and elevated PGE2 together with a decreased level of TNF-α and IL-6. Girinimbine had shown suppressing effects on COX-2 enzymes, but not on COX-1. In addition, significantly upregulated HSP70 and downregulated iNOS were observed in girinimbine treated rat tissue at both the transcriptional and translational level. Our results clearly indicated that girinimbine displayed a significant gastro-protection effect, via the capacity to inhibit inflammatory responses and antioxidant potential.

Total triterpenes from the fruits of Chaenomeles speciosa (Sweet) Nakai protects against indomethacin-induced gastric mucosal injury: involvement of TFF1-mediated EGF/EGFR and apoptotic pathways

OBJECTIVES

Our previous studies indicated that the triterpenes from the fruits of Chaenomeles speciosa (Sweet) Nakai (TCS) owned effectively therapeutic effects on gastric ulcer patients and animals, but its mechanisms have not been fully understood. The current study was to further investigate its protective effect on indomethacin (IND)-damaged RGM-1 cells and rats, as well as its mechanisms involved.

METHODS

The gastroprotection of TCS was evaluated with IND-induced gastric lesions model in RGM-1 cells and rats. In vitro, the proliferation, migration, mitochondrial viability and apoptosis were assessed. In vivo, ulcer index, ulcer inhibition rate, gastric juice acidity, gastric wall mucus (GWM) and histopathology of gastric mucosa were detected. The gastroprotective effects of TCS through the TFF1-mediated EGF/EGFR and apoptotic pathways were measured by qRT-PCR and Western blot assays.

KEY FINDINGS

The results demonstrated that TCS had gastroprotective function, which was related to the amelioration in promoting IND-damaged RGM-1 cell proliferation and migration, hoisting gastric juice acidity and GWM, improving ulcer index and ulcer inhibition rate, attenuating the haemorrhage, oedema, epithelial cell loss and inflammatory cell infiltration of gastric mucosa, upregulating PCNA, Bcl-2, Bcl-xl mRNA and TFF1, EGF, p-EGFR, p-Src, pro-caspase-3, pro-caspase-9 protein expressions, mitochondrial viability, mitochondrial cytochrome c concentration and p-EGFR/EGFR, p-Src/Src, Bcl-2/Bax, Bcl-xl/Bad ratioes, downregulating Bax, Bad, Apaf-1 mRNA and cleaved-caspase-3, cleaved-caspase-9, cleaved PARP-1 protein expressions and cytosol cytochrome c concentration.

CONCLUSIONS

Our present study demonstrated that TCS's gastroprotective effect was closely connected with boosting TFF1 expression, activating TFF1-mediated EGF/EGFR pathway, thus restraining mitochondrial-dependent apoptosis, which provided new insights into interpreting its underlying mechanism and promised to act as a candidate drug to treat gastric mucosal injury.