Wu Shan Shen Cha (Malus asiatica Nakai. Leaves)-Derived Flavonoids Alleviate Alcohol-Induced Gastric Injury in Mice via an Anti-Oxidative Mechanism

Involvement of NO/cGMP Signaling Pathway, Ca2+ and K+ Channels on Spasmolytic Effect of Everlasting Flower Polyphenolic Extract (Helichrysum stoechas (L.) Moench)

Functional gastrointestinal diseases (FGID) are worldwide prevalent conditions. Pharmacological treatments can be ineffective, leading the population to turn to herbal or traditional remedies. Helichrysum stoechas (L.) Moench is a medicinal plant traditionally used in the Iberian Peninsula to treat digestive disorders, but its effects on gastrointestinal motility have not been scientifically demonstrated. The aim of this work was to evaluate the antispasmodic effect of a polyphenolic extract of H. stoechas (HSM), its mechanism of action and its antioxidant activity. Isometric myography studies were performed in rat ileum, and malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA) levels were measured in rat jejunum. HSM reduced the integrated mechanical activity of spontaneous contractions. In Ca²⁺-free medium, HSM reduced the concentration-response curve of CaCl₂ similarly to verapamil. Pre-incubation with the extract blocked the contraction induced by Bay K8644, KCl and carbachol. L-NAME, ODQ, Rp-8-Br-PET-cGMPS, KT-5823, apamin, TRAM-34 and charybdotoxin reduced the relaxant effect of the extract on spontaneous contractions. MDA+4-HDA levels in LPS-treated tissue were reduced by the extract, showing antioxidant activity. In conclusion, HSM showed antispasmodic activity through inhibition of Ca²⁺ influx, activation of the NO/PKG/cGMP pathway and opening of Ca²⁺-activated K⁺ channels. The results suggest that H. stoechas could help in the prevention or treatment of FGIDs.

Comparison of the Antihypertensive Activity of Phenolic Acids

Phenolic acids, found in cereals, legumes, vegetables, and fruits, have various biological functions. We aimed to compare the antihypertensive potential of different phenolic acids by evaluating their ACE inhibitory activity and cytoprotective capacity in EA.hy 926 endothelial cells. In addition, we explored the mechanism underlying the antihypertensive activity of sinapic acid. Of all the phenolic acids studied, sinapic acid, caffeic acid, coumaric acid, and ferulic acid significantly inhibited ACE activity. Moreover, gallic acid, sinapic acid, and ferulic acid significantly enhanced intracellular NO production. Based on the results of GSH depletion, ROS production, and MDA level analyses, sinapic acid was selected to study the mechanism underlying the antihypertensive effect. Sinapic acid decreases endothelial dysfunction by enhancing the expression of antioxidant-related proteins. Sinapic acid increased phosphorylation of eNOS and Akt in a dose-dependent manner. These findings indicate the potential of sinapic acid as a treatment for hypertension.

Quercetin and Osteoarthritis: A Mechanistic Review on the Present Documents

BACKGROUND

Osteoarthritis (OA), as one of the chronic debilitating conditions, affects 15% of people globally and is linked with serious problems, such as cardiovascular diseases, metabolic syndrome, and autoimmune inflammatory disorders. The current therapeutic options for this disease include nonsteroidal anti-inflammatory drugs, surgery, gene therapy, intrasynovial gel injection, and warm needle penetration. However, these approaches may be accompanied by considerable side effects, high costs, and some limitations for patients. Thus, using an alternative way is needed.

SUMMARY

Presently, natural compounds based-therapies, like flavonoids, have acquired much attention in the current era. One of the compounds belonging to the flavonoid family is quercetin, and its therapeutic effects on disorders related to joints and cartilage have been addressed in vivo and in vitro studies.

KEY MESSAGES

In this review, we summarized evidence indicating its curative capacity against OA with a mechanistic insight.

Phytochemical characterization and anti-inflammatory potential of Egyptian Murcott mandarin cultivar waste (stem, leaves and peel)

The stem (S), leaf (L) and fruit peel (P) of Murcott mandarins were separately extracted using 80% ethanol and then fractionated into dichloromethane (DCM) and ethyl acetate (ET). Their metabolic profiles were studied via HPLC-PDA-ESI-MS/MS and afforded a tentative characterization of 98 compounds, including free organic acids, phenolic acid derivatives, flavonoid aglycones, flavonoid glycosides, flavonoids containing 3-hydroxyl-3-methylglutaroyl (HMG) units, coumarin derivatives and limonoids. Column chromatography resulted in isolation of six metabolites for the first time that were identified as nobiletin (C1), isosinensetin (C2), limonin (C3), 4'-demethylnobiletin (C4), stigmasterol-O-glucoside (C5) and hesperidin (C6). In vitro studies of the anti-inflammatory activity of DCM-L against cyclooxygenases (COXs) and 5-lipoxygenase (5-LOX) enzymes revealed that DCM-L showed higher activity than the other tested fractions. The in vivo gastroprotective effects of that fraction were evaluated using alcohol-induced gastric ulcers in rats. The obtained findings validated the gastroprotective and anti-ulcerogenic activities of DCM-L through its anxiolytic, anti-inflammatory, antioxidant and anti-apoptotic effects. Therefore, we recommend the use of Murcott mandarin leaves as a part of a protection strategy for gastric ulcer.

Protective Effects of Anwulignan against HCl/Ethanol-Induced Acute Gastric Ulcer in Mice

Gastric ulcer is one of the most common gastrointestinal diseases. Anwulignan (AN) is a major active component of Schisandra sphenanthera Rehd. This study was designed to evaluate the protective effect of AN against the acute gastric ulcer induced by HCl/ethanol in mice. The mice were given HCl/ethanol by gavage to establish an acute gastric ulcer model. Then, the serum and gastric tissue samples were taken for biochemical analyses. The results showed that the pretreatment with AN could significantly reduce the gastric ulcer index (GUI) and increase the ulcer inhibition rate, indicating that AN can protect against gastric ulcers. AN showed its antioxidant roles by decreasing the content of reactive oxygen species (ROS), malondialdehyde (MDA), and 8-hydroxydeoxyguanosine (8-OHdG) and increasing the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) and anti-inflammatory roles by decreasing the content of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), and myeloperoxidase (MPO) and increasing the content of interleukin-2 (IL-2), interleukin-4 (IL-4), interleukin-10 (IL-10), prostaglandin E2 (PGE2), and nitric oxide (NO) in both serum and gastric tissue. Furthermore, AN also activated the NRF2/ARE signaling pathway and inhibited the MAPK/NF-κB signaling pathway. AN improves the acute gastric ulcer induced by HCl/ethanol in mice, which may be mainly through its antioxidant capacity and anti-inflammatory effect.

Self-assembled micelles enhance the oral delivery of curcumin for the management of alcohol-induced tissue injury

Curcumin (CUR) shows great potential in the management of alcohol-use disorders. However, the hydrophobicity and poor oral bioavailability result in the limited therapeutic efficacy of CUR against alcohol-induced tissue injury. Here, self-assembled Soluplus® micelles (Ms) were developed for the enhanced oral delivery of CUR. CUR-loaded Soluplus® micelles (CUR-Ms) were prepared using a thin-film hydration method and these micelles displayed nearly spherical shape with an average size of 62.80 ± 1.29 nm. CUR in micelles showed the greater stability, solubility and dissolution than free CUR. With the increased water solubility of CUR-Ms and P glycoprotein inhibition of Soluplus®, the absorption rate constant (Ka) and apparent permeability coefficient (Papp) of CUR-Ms in intestines was respectively 3.50 and 4.10 times higher than that of free CUR. Pharmacokinetic studies showed that CUR-Ms significantly improved the oral bioavailability of CUR. Specifically, the AUC0-∞ and C_max of CUR-Ms were increased by 9.45 and 47.38 folds compared to free CUR, respectively. In mice with alcohol-induced tissue injury, the oral administration of CUR-Ms greatly reduced oxidative stress, and significantly defended liver and gastric mucosa from alcoholic damages. The results demonstrated CUR-Ms with good oral bioavailability could represent a promising strategy for the management of alcohol-induced tissue injury.

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

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

Malus hupehensis leaves extract attenuates obesity, inflammation, and dyslipidemia by modulating lipid metabolism and oxidative stress in high-fat diet-induced obese mice

Malus hupehensis leaves (MHL) are used to make traditional Chinese tea. In this study, MHL extract was shown to improve metabolic disorders and inflammatory response in high-fat diet-induced obese mice. MHL extract could reduce body weight, and significantly alleviate liver damage and fat accumulation. MHL extract caused a decrease in the levels of ALT, AST, AKP, TC, TG, LDL-C, and an increase in the level of HDL-C. It also caused a decrease in inflammatory cytokines, including TNF-α, IFN-γ, IL-1β, IL-6, and an increase in the anti-inflammatory cytokine IL-10 and IL-4. MHL extract could upregulate mRNA expression of PPAR-α, LPL, CPT1, CYP7A1, SOD1, SOD2, CAT, GSH1, and GSH-Px and downregulate that of PPAR-γ and C/EBP-α in the liver of obese mice. In conclusion, our work represents the first study demonstrating that MHL extract possesses an anti-obesity effect and alleviates obesity-related symptoms, including dyslipidemia, chronic low-grade inflammatory, and liver damage. PRACTICAL APPLICATIONS: The research may contribute to the development and application of MHL as functional foods or dietary supplement to fight against obesity.

The effect of Malus doumeri leaf flavonoids on oxidative stress injury induced by hydrogen peroxide (H2O2) in human embryonic kidney 293 T cells

BACKGROUND

In this study, Malus doumeri leaf flavonoids (MDLF) were used as the research object to observe their in vitro antioxidant stress ability. Hydrogen peroxide (H2O2) was used to induce oxidative stress in 293 T cells.

METHODS

MTT, flow cytometry, and qPCR were used to verify the effect of MDLF.

RESULTS

In vitro cell experiments showed that at a concentration of 0-160 μg/mL, MDLF did not affect the normal proliferation of human embryonic kidney 293 T cells (HEK 293 T cells), and MDLF had no cytotoxic effect in this concentration range. It was found that MDLF could maintain the survival of HEK 293 T cells (82.6%) at a high concentration (160 μg/mL). Morphological observation also found that MDLF can inhibit the cell structure imperfection caused by H2O2. It was also observed that MDLF could significantly increase the levels of catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GSH-Px) and reduce the level of malondialdehyde (MDA). The results of quantitative polymerase chain reaction (qPCR) showed that MDLF could significantly up-regulate the mRNA expression levels of CAT, SOD, GSH, GSH-Px, B-cell lymphoma-2 (Bcl-2) and downregulate the expression levels of B-cell lymphoma-2 associated x protein (Bax), tumor necrosis factor-alpha (TNF-α), and nuclear factor kappa-B (NF-κB) in oxidative stress-injured cells. The HPLC analysis showed that MDLF contained hyperin, isoquercetin, quercitrin, hesperidin, myricetin, baicalin and quercetin.

CONCLUSION

From the experimental results, it was observed that MDLF has a strong anti-oxidation ability in vitro, and it can interfere with the oxidative stress damage caused by H2O2 in 293 T cells. Therefore, MDLF is a type of natural substance with good anti-oxidant effect, and it has the potential to interfere with many diseases.

Effect of Malus asiatica Nakai Leaf Flavonoids on the Prevention of Esophageal Cancer in C57BL/6J Mice by Regulating the IL-17 Signaling Pathway

Background

The aim of this study was to observe the preventive effect of flavonoids extracted from Malus asiatica Nakai leaves (FMANL) on esophageal cancer in mice, especially the ability of FMANL to regulate the interleukin 17 (IL-17) signaling pathway during this process.

Materials and Methods

The C57BL/6J mice were treated with 4-nitroquinoline N-oxide (4NQO) to induce esophageal cancer, and the visceral tissue index and the serum and esophageal tissue indexes of mice were used to verify the effect of FMANL.

Results

The experimental results showed that FMANL can effectively control the changes in visceral tissue caused by esophageal cancer. FMANL could increase the cytokine levels of interleukin 10 (IL-10), monocyte chemotactic protein 1 (MCP-1) and decrease the cytokine levels of tumor necrosis factor alpha (TNF-α), interferon-γ (IFN-γ), interleukin 6 (IL-6), and interleukin 12p70 (IL-12p70) in serum of mice with esophageal cancer. FMANL could also reduce CD3⁺, CD4⁺, and CD8⁺ and enhance CD19⁺ mouse peripheral blood lymphocytes. The results of qPCR and Western blot analysis showed that FMANL could down-regulate the mRNA and protein expression levels of IL-17, interleukin 23 (IL-23), interleukin 1 beta (IL-1β), chemokine (C-X-C) ligand 1 (CXCL1), chemokine (C-X-C) ligand 2 (CXCL2), S100 calcium-binding protein A8 (S100A8), S100 calcium-binding protein A9 (S100A9), matrix metalloprotein 9 (MMP-9), and matrix metalloprotein 13 (MMP-1) in mice with esophageal cancer. High-performance liquid chromatography (HPLC) detection showed that FMANL contained 10 chemicals, including rutin, hyperoside, isoquercitrin, dihydroquercetin, quercitrin, hesperidin, myricetin, baicalin, neohesperidin dihydrochalcone, and quercetin.

Conclusion

It could be concluded that FMANL can effectively prevent experimentally induced esophageal cancer in mice, and its effects might be obtained from 10 compounds present in FMANL.

Liubao Insect tea polyphenols prevent HCl/ethanol induced gastric damage through its antioxidant ability in mice

The aim of this study was to study the preventive effects of polyphenols extracted from Liubao Insect tea on gastric injury. The content of Liubao Insect tea polyphenols (LITP) was 72.36% by ion precipitation extraction method. HCl/ethanol-induced gastric injury in mice led to increased gastric juice volume and decreased pH. LITP increased the gastric juice pH value and reduced the gastric juice volume at slightly lower quantities than ranitidine. Visual observation of gastric tissue showed that LITP could effectively reduce the area of gastric injury, and higher concentrations of LITP had a greater effect. Pathological observation also confirmed that LITP can reduce the cell damage and inflammatory effects, and play a role in preventing gastric injury. Serum cytokine assays showed that LITP could reduce the levels of IL-6 (interleukin 6), TNF-α (tumor necrosis factor alpha) and IFN-γ (interferon gamma) induced by gastric injury, and the effects of higher concentration of LITP were similar to those of ranitidine. The results showed that LITP could increase SOD (superoxide dismutase) and GSH (glutathione) levels; decrease MDA (malondialdehyde) and MPO (myeloperoxidase) levels; up-regulate the expression of Cu/Zn-SOD (cuprozinc-superoxide dismutase), Mn-SOD (manganese superoxide dismutase), CAT (catalase), nNOS (neuronal nitric oxide synthase), eNOS (endothelial nitric oxide synthase); and down-regulate the expression of iNOS (inducible nitric oxide synthase), COX-2 (cyclooxygenase-2), TNF-α, and IL-1β (interleukin-1 beta) in mice with gastric injury, thus inhibiting gastric injury. We demonstrate that LITP is an active substance which could prevent gastric injury in experimental animals. With the increase of LITP concentration, its effects on preventing gastric injury were stronger and similar to those of ranitidine.

The aim of this study was to study the preventive effects of polyphenols extracted from Liubao Insect tea on gastric injury.