Hesperidin, a citrus flavanone glycoside, accelerates the gastric healing process of acetic acid-induced ulcer in rats

Dose-dependent protective effects of Lactobacillus rhamnosus GG against stress-induced ulcer

BACKGROUND

Stress-related diseases are on the rise and stress is one of the common factors that lead to ulcer. Stress-induced mucosal bleeding is a serious complication observed in many critically ill patients. Due to the harmful side effects of proton pump inhibitors, natural and active alternative treatment methods for peptic ulcer treatment that are safe in terms of side effects are an urgent need for human health. We aimed to investigate the dose-dependent protective effects of Lactobacillus rhamnosus GG (LGG) against stress ulcers induced by cold restraint stress in rats. This study was performed in a total of 42 rats, in control group (C), stress group (S), pantoprazol (20 mg kg-1 day-1) group (P), LGG (3 × 108 cfu mL-1 day-1) + stress group (M1), LGG (15 × 108  mL-1 day-1) + stress group (M5) and LGG (30 × 108  mL-1 day-1) + stress group (M10) (each n = 7). Ulceration areas (mm2) were determined quantitatively with ImageJ software. Glucocorticoid, catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels were determined by ELISA and malondialdehyde levels were determined by spectrophotometric measurement. Histopathological examinations were performed in gastric tissue.

RESULTS

Therapeutic dose of LGG increased CAT, SOD and GPx levels; prevented excessive activation of the hypothalamic-pituitary-adrenal axis; reduced ulceration and bleeding in the gastric mucosal layer; and provided stabilization of mast cells.

CONCLUSIONS

We can suggest that LGG may be beneficial for reducing the negative effects of stress on the body, for protecting against ulcer disease and for reducing or preventing the risk of stress-induced gastrointestinal bleeding in patients staying in intensive care units. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Recent understanding of the mechanisms of the biological activities of hesperidin and hesperetin and their therapeutic effects on diseases

Flavonoids are natural phytochemicals that have therapeutic effects and act in the prevention of several pathologies. These phytochemicals can be found in lemon, sweet orange, bitter orange, clementine. Hesperidin and hesperetin are citrus flavonoids from the flavanones subclass that have anti-inflammatory, antioxidant, antitumor and antibacterial potential. Preclinical studies and clinical trials demonstrated therapeutical effects of hesperidin and its aglycone hesperetin in various diseases, such as bone diseases, cardiovascular diseases, neurological diseases, respiratory diseases, digestive diseases, urinary tract diseases. This review provides a comprehensive overview of the biological activities of hesperidin and hesperetin, their therapeutic potential in various diseases and their associated molecular mechanisms. This article also discusses future considerations for the clinical applications of hesperidin and hesperetin.

Effects of the protective and therapeutic effect of yogurt enriched with Citrus sinensis essential oil against ibuprofen-induced gastric ulcer in elderly rats

The aim of this study was to evaluate the effect of Citrus sinensis essential oil (EO) on the proximate composition of yogurt over a 28-day shelf life and to investigate the therapeutic and prophylactic effects of functional yogurt on ibuprofen-induced gastric ulcers in a rat model. It was observed that the yogurt group containing C. sinensis EO had higher acidity, total solids, and ash values. Histologic evaluation of the stomachs of rats with gastric ulcers revealed that rats fed with functional yogurt had fewer lesions compared to the control group. The treatment group had fewer lesions than the positive control (p > 0.05). Lesions in the glandular mucosa of the prophylactic group were significantly lower than those in the positive control group (p < 0.05). Yogurt with C. sinensis EO may be beneficial in reducing the severity of ulcers and improving overall health.

The Behavior of Phenolic Compounds from Apples during Simulated Gastrointestinal Digestion with Focus on Chlorogenic Acid

The fate of phenolic compounds during digestion is important for their bioactive effects in the digestive tract. The aim was to study the various phenolic compounds occurring in the peel and flesh of apples in in vitro simulated gastrointestinal digestion, focusing on the behavior of chlorogenic acids. Additionally, the behavior of individual chlorogenic acids (chlorogenic, neochlorogenic, and cryptochlorogenic) was studied in models of simulated salivary, gastric, and intestinal fluid electrolyte solutions (SSF, SGF, SIF). At the end of the intestinal phase of the digestion of peel and flesh, the amount of recovered dihydrochalcones and flavonols increased or was similar to the amount in the gastric phase, which showed their stability. Anthocyanins and flavan-3-ols decreased, which suggests their biotransformation. Chlorogenic acid isomerized into neochlorogenic and cryptochlorogenic acid: chlorogenic acid from the peel into 22% and 41% of the isomers in the salivary and intestinal phases, respectively; chlorogenic acid from the flesh into 12% of the isomers in the intestinal phase. Similarly, chlorogenic acid isomerized in model solutions (20% and 26% of the isomers in SSF and SIF, respectively). Neochlorogenic and cryptochlorogenic acid isomerized in SSF and SIF into other two forms. They were all stable in SGF. For bioactive effects in the digestive tract, the biotransformation of chlorogenic acids should be considered.

Comprehensive and critical view on the anti-inflammatory and immunomodulatory role of natural phenolic antioxidants

The immune response encompasses innate and adaptive immunity, each with distinct and specific activities. The innate immune system is constituted by phagocytic cells, macrophages, monocytes and neutrophils, the cascade system, and different classes of receptors such as toll-like receptors that are exploited by the innate immune cells. The adaptive immune system is antigen-specific, encompassing memory lymphocytes and the corresponding specific receptors. Inflammation is understood as an activation of different signaling pathways such as toll-like receptors or nuclear factor kappa-light-chain-enhancer of activated B cells, with an increase in nitric oxide, inflammatory cytokines and chemokines. Increased oxidative stress has been identified as main source of chronic inflammation. Phenolic antioxidants modulate the activities of lymphocytes and macrophages by impacting cytokines and nitric oxide release, exerting anti-inflammatory effect. The nuclear-factor kappa-light-chain-enhancer of activated B cells signaling pathway and the mitogen-activated protein kinase pathway are targeted, alongside an increase in nuclear factor erythroid 2-related factor mediated antioxidant response, triggering the activity of antioxidant enzymes. The inhibitive potential on phospholipase A2, cyclooxygenase and lipoxygenase in the arachidonic acid pathway, and the subsequent reduction in prostaglandin and leukotriene generation, reveals the potential of phenolics as inflammation antagonists. The immunomodulative potential encompasses the capacity to interfere with proinflammatory cytokine synthesis and with the expression of the corresponding genes. A diet rich in antioxidants can result in prevention of inflammation-related pathologies. More investigations are necessary to establish the role of these antioxidants in therapy. The appropriate delivery system and the prooxidant effects exhibited at large doses, or in the presence of heavy metal cations should be regarded.

Bio-evaluations of sericin coated hesperidin nanoparticles for gastric ulcer management

Gastric ulcers are worrying, and their worsening conditions may result in bleeding in the internal lining of the stomach. The problem is annoying, and both patients and professionals are still not satisfied with the available treatment options. Hesperidin, a flavonoid molecule with potent anti-inflammatory and antioxidant effects, can work like witchcraft to repair gastric ulcers and preserve the stomach lining. Here, we employed a strategy that involved covering the surface of the nano-lipid carriers (NLCs) with sericin before encasing the hesperidin within (Se-He-NLC). Sericin, a biodegradable polymer increases the muco-adhesion with stomach lining and deployment of hesperidin in controlled manner. Se-He-NLCs were physico-chemically characterized for drug loading, encapsulation, particle size, morphology, drug release, chemical stability, and chemical bonding. The nanocarriers showed first order drug release in a controlled manner. Se-He-NLCs showed better in vitro permeation and ex vivo mucoadhesion, thereby by promoting the in vivo bioavailability. Se-He-NLCs also promoted the reduced glutathione (GSH) and glutathione-S-transferase (GST) levels by 2.24- and 1.61-folds, respectively in the stomach lining, and also the regulation of superoxide dismutase (SOD) and catalase (CAT) activities parallel to the control group. In addition, tissues lipid hydroperoxides (LOOH) and myeloperoxidase (MPO) activity were reduced significantly with Se-He-NLCs administration. Se-He-NLC therapy of stomach ulcers in vivo demonstrated better binding ratio and ulcer healing potential. This approach reveals huge capacity for delivering therapies to treat gastric ulcers based on the clinical significance of sericin coated hesperidin nanocarriers in gastric ulcer treatment.

Exploring the Effect of Deep-Sea Water on the Therapeutic Potential of the Anti-Inflammatory Response in an Indomethacin-Induced Gastric Ulcer Rat Model

Gastric ulcers are often exacerbated by factors such as nonsteroidal anti-inflammatory drugs (NSAIDs) and inflammation, and they have a substantial impact on a significant portion of the population. Notably, indomethacin is recognized as a prominent contributor to ulcers. This study investigated this potential method, with normalization to the anti-inflammatory and antiulcer properties of deep-sea water (DSW)-derived mineral water, using an indomethacin-induced gastric ulcer model in rats. The study involved four groups (n = 6 rats/group): normal control group (CON), indomethacin-only group (IND), indomethacin with trace mineral water group (TM), and indomethacin with high magnesium low sodium water group (HMLS). For three weeks, the CON and IND groups consumed tap water, while the TM and HMLS groups had access to mineral water. Gastric ulcers were induced on the final day using indomethacin, for all groups except the CON group. The results demonstrated that HMLS intake significantly improved gastric mucosal damage, preserved mucin stability, and increased gastric thickness, indicating its potential to prevent and alleviate indomethacin-induced gastric ulcers. Furthermore, HMLS consumption led to the upregulation of key genes associated with inflammation and a reduction in inflammatory cytokines. These findings suggest that DSW-derived mineral water, and particularly its high Mg2+ content, may offer promising health benefits including anti-inflammatory and anti-ulcer properties.

Beneficial effects of phenolic compounds: native phenolic compounds vs metabolites and catabolites

In the human body, the positive effects of phenolic compounds are increasingly observed through their presence in tissues and organs in their native form or in the form of metabolites or catabolites formed during digestion, microbial metabolism, and host biotransformation. The full extent of these effects is still unclear. The aim of this paper is to review the current knowledge of beneficial effects of native phenolic compounds or their metabolites and catabolites focusing on their role in the health of the digestive system, including disorders of the gastrointestinal and urinary tracts and liver. Studies are mostly connecting beneficial effects in the gastrointestinal and urinary tract to the whole food rich in phenolics, or to the amount of phenolic compounds/antioxidants in food. Indeed, the bioactivity of parent phenolic compounds should not be ignored due to their presence in the digestive tract, and the impact on the gut microbiota. However, the influence of their metabolites and catabolites might be more important for the liver and urinary tract. Distinguishing between the effects of parent phenolics vs metabolites and catabolites at the site of action are important for novel areas of food industry, nutrition and medicine.

Combination of chemical profiling and network pharmacology analysis to investigate the potential mechanism of Li-Zhong-Xiao-Pi granules in the treatment of gastric precancerous lesions

Li-Zhong-Xiao-Pi granules (LZXP) are effective for treating gastric precancerous lesions (GPL) in traditional Chinese medicine. However, the active compounds of LZXP and their potential therapeutic mechanism in GPL remained unclarified. The purpose of this study is to investigate the chemical composition and potential targets of LZXP. Based on the accurate masses, ion fragments, and literature data, a total of 128 compounds were identified in the LZXP sample using ultra-performance liquid chromatography and quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) in both positive and negative ion modes, and 28 of these compounds were exactly determined by comparison with authentic reference standards. Meanwhile, 11 typical components were quantified via UPLC during a 24 min period. The linearity, accuracy, stability and recovery of the method were all proven. Through the network pharmacological analysis, six chemicals (quercetin, 4'-hydroxywogonin, sinensetin, 5, 7, 8, 3', 4'-pentamethoxyflavanone, 8-gingerdione and quercetin) were identified as the active ingredients, and five LZXP targets (AKT1, CYP1B1, PTGS2, MMP9 and EGFR) were found to be the crucial molecules in the treatment of GPL. This study provides a systematic and applicable method for the rapid screening and identification of the chemical constituents from LZXP, and an effective understanding the mechanism of LZXP in the treatment of GPL.

Hesperidin Reversed Long-Term N-methyl-N-nitro-N-Nitroguanidine Exposure Induced EMT and Cell Proliferation by Activating Autophagy in Gastric Tissues of Rats

Gastric cancer is a common malignant tumor worldwide. N-methyl-N-nitro-N-nitroguanidine (MNNG) is one of the most important inducing factors of gastric cancer. Autophagy can affect the occurrence and development of gastric cancer, but the mechanism is not clear. Chemoprevention has been shown to be a rational and very promising approach to the prevention of gastric cancer. Hesperidin is a citrus flavone, an abundant polyphenol in citrus fruits and traditional Chinese medicine. It has an excellent phytochemistry that plays an intervention role in gastric cancer. However, it is unclear whether long-term exposure to MNNG will affect the occurrence of gastric cancer by regulating autophagy and whether hesperidin can play an intervention role in this process. In the present study, we demonstrated that long-term MNNG exposure inhibits autophagy in stomach tissues of rats, promotes the epithelial-mesenchymal transition (EMT) process and cell proliferation and suppresses the activity of the PI3K/AKT pathway. We further found that after rapamycin-activated autophagy, long-term MNNG exposure promoted cell proliferation and EMT were inhibited. In addition, hesperidin promotes autophagy and the activity of the PI3K/AKT pathway, as well as the suppression of proliferation and EMT in the stomach tissues of rats. Our findings indicate that hesperidin reverses MNNG-induced gastric cancer by activating autophagy and the PI3K/AKT pathway, which may provide a new basis for the early prevention and treatment of MNNG-induced gastric cancer.

Atractylone Alleviates Ethanol-Induced Gastric Ulcer in Rat with Altered Gut Microbiota and Metabolites

Background

Gastric ulcer (GU) is the most common multifactor gastrointestinal disorder affecting millions of people worldwide. There is evidence that gut microbiota is closely related to the development of GU. Atractylone (ATR) has been reported to possess potential biological activities, but research on ATR alleviating GU injury is unprecedented.

Methods

Helicobacter pylori (H. pylori)-induced GU model in zebrafish and ethanol-induced acute GU model in rat were established to evaluate the anti-inflammatory and ulcer inhibitory effects of ATR. Then, 16S rRNA sequencing and metabolomics analysis were performed to investigate the effect of ATR on the microbiota and metabolites in rat feces and their correlation.

Results

Therapeutically, ATR inhibited H. pylori-induced gastric mucosal injury in zebrafish. In the ulceration model of rat, ATR mitigated the gastric lesions damage caused by ethanol, decreased the ulcer area, and reduced the production of inflammatory factors. Additionally, ATR alleviated the gastric oxidative stress injury by increasing the activity of superoxide dismutase (SOD) and decreasing the level of malondialdehyde (MDA). Furthermore, ATR played a positive role in relieving ulcer through reshaping gut microbiota composition including Parabacteroides and Bacteroides and regulating the levels of metabolites including amino acids, short-chain fatty acids (SCFAs), and bile acids.

Conclusion

Our work sheded light on the mechanism of ATR treating GU from the perspective of the gut microbiota and explored the correlation between gut microbiota, metabolites, and host phenotype.

Gastroprotective activity of polysaccharide from the fruiting body of Hericium erinaceus against acetic acid-induced gastric ulcer in rats and structure of one bioactive fraction

This study aimed at investigating gastroprotective activity of Hericium erinaceus polysaccharide (HEP) and characterizing one of its bioactive fractions. Acetic acid-induced gastric ulcer (GU) rat model was used to evaluate the gastroprotective activity of HEP, while H₂O₂-induced injury GES-1 cell model was conducted to screen the bioactive fractions from HEP. Moreover, one of the bioactive fractions was characterized using methylation and 1D/2D NMR analysis. Results indicated HEP treatment could ameliorate acetic acid-induced GU in rats. HEP supplement decreased levels of interleukin-6, tumor necrosis factor-α and malondialdehyde and myeloperoxidase activity, and increased releases of nitric oxide, prostaglandin E2, epidermal growth factor, vascular endothelial growth factor and basic fibroblast growth factor and superoxide dismutase activity in gastric tissues of ulcerated rats. Five purified polysaccharides from HEP were screened to be bioactive fractions with cytoprotection on H₂O₂-induced injury in GES-1 cells. Among them, RP-S was characterized to be a (1 → 6)-β-D-glucan, whose backbone was composed of →6)-β-D-Glcp-(1 → residue and branched with T-β-D-Glcp-(1 → residue at O-3 position. In conclusion, HEP possessed gastroprotection against acetic acid-induced GU in rats and one of its bioactive fractions was a β-D-glucan. This study supports the utilization of HEP in anti-GU and provides evidences for the structure of gastroprotective HEP.

Treatment of Gastrointestinal Disorders-Plants and Potential Mechanisms of Action of Their Constituents

The worldwide prevalence of gastrointestinal diseases is about 40%, with standard pharmacotherapy being long-lasting and economically challenging. Of the dozens of diseases listed by the Rome IV Foundation criteria, for five of them (heartburn, dyspepsia, nausea and vomiting disorder, constipation, and diarrhoea), treatment with herbals is an official alternative, legislatively supported by the European Medicines Agency (EMA). However, for most plants, the Directive does not require a description of the mechanisms of action, which should be related to the therapeutic effect of the European plant in question. This review article, therefore, summarizes the basic pharmacological knowledge of synthetic drugs used in selected functional gastrointestinal disorders (FGIDs) and correlates them with the constituents of medicinal plants. Therefore, the information presented here is intended as a starting point to support the claim that both empirical folk medicine and current and decades-old treatments with official herbal remedies have a rational basis in modern pharmacology.

Preventive Effect of Gonggan (Citrus Reticulata Blanco Var. Gonggan) Peel Extract on Ethanol/HCl-Induced Gastric Injury in Mice via an Anti-oxidative Mechanism

Gonggan (Citrus reticulata Blanco var. gonggan) is one of the most popular citruses. In this study, the effect of Gonggan peel extract (GPE) on gastric injury was investigated. The components in GPE were analysed by HPLC and the gastric injury model in mice was established by ethanol/hydrochloric acid. After treatment by GPE, the pathological changes of gastric tissue were observed by optical microscope. The levels of oxidative stress and inflammation were measure by kit. And the mRNA expression of related gene was determined by qPCR assay. HPLC result showed GPE mainly contained the flavonoids narirutin, hesperidin, nobiletin, tangeretin and 5-demethylnobiletin. Morphological and pathological analysis of gastric tissue revealed that GPE could relieve gastric injury. Also, GPE increased the levels of SOD, GSH-Px, and CAT and decreased the level of MDA. Moreover, GPE decreased the levels of the inflammatory cytokines TNF-α, IFN-γ, IL-1β, and IL-6 to suppress inflammation. In addition, the q-PCR results showed that GPE upregulated the mRNA expression of SOD1, SOD2, γ-GCS, GSH-Px, CAT, and IκBα and downregulated the mRNA expression of NF-κB. In conclusion, GPE alleviated gastric injury caused by ethanol/hydrochloric acid by inhibiting oxidative stress and the inflammatory response. The mechanism by which GPE protects gastric tissues may involve the antioxidative pathway. Therefore, GPE has great potential to be developed as a product to prevent gastric injury.

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.

Activation of transient receptor potential vanilloid channel 4 contributes to the development of ethanol-induced gastric injury in mice

The transient receptor potential vanilloid channel 4 (TRPV4) is associated with the development of several pathologies, particularly gastric disorders. However, there are no studies associating this receptor with the pathophysiology of gastric erosions. The aim of this study was to investigate the role of TRPV4 in the development of ethanol-induced gastric damage in vivo. Gastric lesions were induced by ethanol in Swiss mice pretreated with TRPV4 antagonists, GSK2193874 (0.1; 0.3 and 0.9 mg/kg) or Ruthenium red (0.03; 0.1 or 0.3 mg/kg) or its agonist, GSK1016790A (0.9 mg/kg). Gastric mucosal samples were taken for histopathology, immunohistochemistry, atomic force microscopy and evaluation of antioxidant parameters. The gastric mucus content and TRPV4 mRNA expression were analyzed. Ethanol exposure induced upregulation of gastric mRNA and protein expression of TRPV4. TRPV4 blockade promoted gastroprotection against ethanol-induced injury on macro- and microscopic levels, leading to reduced hemorrhage, cell loss and edema and enhanced gastric mucosal integrity. Moreover, an increase in superoxide dismutase (SOD) and glutathione (GSH) activity was observed, followed by a decrease in malondialdehyde (MDA) levels. TRPV4 blockade during alcohol challenge reestablished gastric mucus content. The combination of TRPV4 agonist and ethanol revealed macroscopic exacerbation of gastric damage area. Our results confirmed the association of TRPV4 with the development of gastric injury, showing the importance of this receptor for further investigations in the field of gastrointestinal pathophysiology and pharmacology.

Taxifolin and gastro-adhesive microparticles containing taxifolin promotes gastric healing in vivo, inhibits Helicobacter pylori in vitro and proton pump reversibly in silico

Taxifolin (3,5,7,3,4-pentahydroxy flavanone or dihydroquercetin, Tax) was identified as a gastroprotective compound and a gastroadhesive formulation was recently developed to prolong its residence time and release in the stomach. So, the gastric healing effectiveness of Tax and gastro-mucoadhesive microparticles containing Tax (MPTax) against the acetic acid induced-gastric ulcer in rats was investigated in this study. Moreover, the interactions between Tax and H⁺/K⁺-ATPase were investigated in silico, and its anti- H. pylori activity was determined in vitro. The oral treatment with MPTax (81.37 mg/kg, containing 12.29% of Tax) twice a day for seven days reduced the ulcer area by 63%, compared to vehicle-treated group (Veh: 91.9 ± 10.3 mm²). Tax (10 mg/kg, p.o) reduced the ulcer by 40% but with a p = 0.07 versus Veh group. Histological analysis confirmed these effects. Tax and MPTax increased the gastric mucin amount, reduced the myeloperoxidase activity, and increased the glutathione reduced content at ulcer site. However, only MPTax decreased the lipoperoxide accumulation at ulcer site. Besides, Tax and MPTax normalize the catalase and glutathione S-transferase activity. Tax showed reversible interaction with H⁺/K⁺-ATPase in silico and its anti-H. pylori effects was confirmed (MIC = 625 μg/mL). These results suggest that the antiulcer property of Tax involves the strengthening of the gastric protective factors in parallel to its inhibitory interaction with H⁺/K⁺-ATPase and H. pylori. Considering that ulcer healing action displayed by Tax was favored by gastroadhesive microparticles, this approach seems to be promising for its oral delivery to treat acid-peptic diseases.

Novel Carbon Dots Derived from Glycyrrhizae Radix et Rhizoma and Their Anti-Gastric Ulcer Effect

Glycyrrhizae Radix et Rhizoma (GRR) is one of the commonly used traditional Chinese medicines in clinical practice, which has been applied to treat digestive system diseases for hundreds of years. GRR is preferred for anti-gastric ulcer, however, the main active compounds are still unknown. In this study, GRR was used as precursor to synthesize carbon dots (CDs) by a environment-friendly one-step pyrolysis process. GRR-CDs were characterized by using transmission electron microscopy, high-resolution TEM, fourier transform infrared, ultraviolet-visible and fluorescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and high-performance liquid chromatography. In addition, cellular toxicity of GRR-CDs was studied by using CCK-8 in RAW264.7 cells, and the anti-gastric ulcer activity was evaluated and confirmed using mice model of acute alcoholic gastric ulcer. The experiment confirmed that GRR-CDs were the spherical structure with a large number of active groups on the surface and their particle size ranged from 2 to 10 nm. GRR-CDs had no toxicity to RAW264.7 cells at concentration of 19.5 to 5000 μg/mL and could reduce the oxidative damage of gastric mucosa and tissues caused by alcohol, as demonstrated by restoring expression of malondialdehyde, superoxide dismutase and nitric oxide in serum and tissue of mice. The results indicated the explicit anti-ulcer activity of GRR-CDs, which provided a new insights for the research on effective material basis of GRR.

Citrus flavonoids and their antioxidant evaluation

The antioxidant ability is the link and bridge connecting a variety of biological activities. Citrus flavonoids play an essential role in regulating oxidative stress and are an important source of daily intake of antioxidant supplements. Many studies have shown that citrus flavonoids promote health through antioxidation. In this review, the biosynthesis, composition and distribution of citrus flavonoids were concluded. The detection methods of antioxidant capacity of citrus flavonoids were divided into four categories: chemical, cellular, animal and clinical antioxidant capacity evaluation systems. The modeling methods, applicable scenarios, and their relative merits were compared based on these four systems. The antioxidant functions of citrus flavonoids under different evaluation systems were also discussed, especially the regulation of the Nrf2-antioxidases pathway. Some shortcomings in the current research were pointed out, and some suggestions for progress were put forward.

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.

Preparation and in vitro/in vivo evaluations of novel ocular micelle formulations of hesperetin with glycyrrhizin as a nanocarrier

The purpose of this study was to explore the potential of formulating hesperetin into an ophthalmic solution with dipotassium glycyrrhizinate (DG) as a micelle nanocarrier. A DG-based micelle ophthalmic solution encapsulating hesperetin (DG-Hes) was developed and its in vitro/in vivo characterizations were evaluated. The optimal formulation featured a DG/hesperetin (Hes) weight ratio of 12:1 and an encapsulation efficiency of 90.4 ± 1.7%; The optimized DG-Hes was characterized as small uniform spheres with an average micelle size of 70.93 ± 3.41 nm, a polydispersity index of 0.11 ± 0.02, and an electrically negative surface (-36.12 ± 2.79 mV). The DG-Hes ophthalmic solution had good tolerance in rabbit eyes. DG-Hes significantly improved the in vitro passive permeation, ex vivo corneal permeation, and in vivo ocular bioavailability of Hes. DG-Hes showed markedly increases in in vitro antioxidant activity. In vitro antibacterial activity tests revealed a lower minimum inhibitory concentration and lower minimum bactericidal concentration for DG-Hes ophthalmic solution were lower than for free Hes. DG-Hes ophthalmic solution also significantly reduced symptoms of eye infection in the rabbit bacterial keratitis model when compared to a Hes suspension. These results suggest that DG-Hes eye drops may be useful as a new ophthalmic preparation for the treatment of ocular diseases, especially bacterial ophthalmopathy.

Preventative and Therapeutic Potential of Flavonoids in Peptic Ulcers

Peptic ulcer disease is a common gastrointestinal tract disorder that affects up to 20% of the population of the world. Treatment of peptic ulcer remains challenging due to the limited effectiveness and severe side effects of the currently available drugs. Hence, natural compounds, owing to their medicinal, ecological, and other safe properties, are becoming popular potential candidates in preventing and treating peptic ulcers. Flavonoids, the most abundant polyphenols in plants, exhibit gastroprotective effects against peptic ulcer both in vivo and in vitro. In this review, we summarized the anti-ulcer functions and mechanisms, and also the bioavailability, efficacy, and safety, of flavonoid monomers in the gastrointestinal tract. Flavonoids exerted cytoprotective and rehabilitative effects by not only strengthening defense factors, such as mucus and prostaglandins, but also protecting against potentially harmful factors via their antioxidative, anti-inflammatory, and antibacterial activities. Although controlled clinical studies are limited at present, flavonoids have shown a promising preventable and therapeutic potential in peptic ulcers.

Comparisons of Chemical Profiles and Gastroprotective Effects of Citri Sarcodactylis Fructus Pre- and Poststeam Processing

Background

Citri Sarcodactylis Fructus (CSF) is widely used as folk medicine in traditional Chinese medicine (TCM). The dried and steam-processed CSF (SCSF) has been employed for harmonizing the stomach over thousands of years under the guidelines of TCM theory. However, little is known about the differences in chemical compositions between CSF and SCSF. Moreover, the gastroprotective effects of CSF and SCSF on ethanol-induced gastric mucosal injuries in rats have yet to be investigated. Consequently, the present study aimed to investigate the chemical differences and gastroprotective effects of CSF and SCSF, providing some experimental framework for the development of CSF and SCSF.

Methods

The chemical compositions of CSF and SCSF extracts were determined using an ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometer (UPLC-Q-TOF-MS), and their gastroprotective effects of different doses were assessed in rats with ethanol-induced gastric injuries on the levels of oxidative stress and inflammatory cytokines.

Results

A total of 42 components were identified in CSF and SCSF, and most of them were flavonoids, limonoids, coumarins, and glycosides. There were no differences in the compositions between CSF and SCSF, but the relative contents of the components were different. Among them, nine screened compounds were considered as potential discriminating markers responsible for the differences between CSF and SCSF. Besides, pretreatments with CSF and SCSF markedly improved the gastric mucosal injuries in rats for their antioxidant and anti-inflammatory properties. And SCSF exhibited a better gastroprotective effect than CSF.

Conclusion

The compositions of CSF were unchanged after steam-processing, while the relative contents of their components were changed. These changes may be the major reasons for the differentiation of their efficacies. In addition, CSF and SCSF could alleviate ethanol-induced gastric mucosal injury through the enhancement of antioxidant and anti-inflammatory activities. SCSF exhibited a better gastroprotective effect than CSF, which emphasized the necessity of steam processing.

Hesperidin protects against cadmium-induced pancreatitis by modulating insulin secretion, redox imbalance and iNOS/NF-ĸB signaling in rats

AIM

Cadmium is a persistent ubiquitous environmental toxicant that elicits several biological defects on delicate body organs. Growing evidence suggests that cadmium (Cd) may perturb signaling pathways to induce oxidative pancreatitis. Thus, we explored whether hesperidin, a flavonone, could mitigate Cd-induced oxidative stress-mediated inflammation and pancreatitis in Wistar rats.

MAIN METHODS

Forty (40) rats randomly assigned to 5 groups (n = 8) were administered normal saline or hesperidin (Hsp) followed by Cd intoxication for 28 days.

KEY FINDINGS

Cadmium accumulated in the pancreas of rats, and markedly decreased insulin, pancreatic superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities and glutathione (GSH) level. Cadmium considerably increased malondialdehyde (MDA), serum lipase and amylase activities. Cadmium induced pancreatic pro-inflammation via over-expression of inducible nitric oxide synthase (iNOS), nuclear factor-ĸB (NF-κB), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), along with histopathological alterations. Hesperidin prominently decreased serum amylase and lipase activities, and markedly increased insulin level, pancreatic antioxidant defense mechanism, whereas iNOS, NF-κB, IL-6 and TNF-α levels significantly decreased. Changes in histology confirmed our biochemical findings.

SIGNIFICANCE

Our findings suggest that Cd induced pancreatitis via pro-inflammation and oxidative stress; Hsp, thus, protects against Cd-induced pancreatitis via attenuation of oxidative stress and proinflammatory responses in pancreas.