INHIBITORY ACTIVITY OF MANGIFERIN ON HELICOBACTER PYLORI-INDUCED INFLAMMATION IN HUMAN GASTRIC CARCINOMA AGS CELLS

A differential-targeting core-shell microneedle patch with coordinated and prolonged release of mangiferin and MSC-derived exosomes for scarless skin regeneration

Microneedles for skin regeneration are conventionally restricted by uncontrollable multi-drug release, limited types of drugs, and poor wound adhesion. Here, a novel core-shell microneedle patch is developed for scarless skin repair, where the shell is composed of hydrophilic gelatin methacryloyl (GelMA) loaded with mangiferin, an anti-inflammatory small molecule, and the core is composed of hydrophobic poly (lactide-co-propylene glycol-co-lactide) dimethacrylates (PGLADMA) loaded with bioactive macromolecule and human mesenchymal stromal cell (hMSC)-derived exosomes. This material choice provides several benefits: the GelMA shell provides a swelling interface for tissue interlocking and rapid release of mangiferin at an early wound healing stage for anti-inflammation, whereas the PGLADMA core offers long-term encapsulation and release of exosomes (30% release in 3 weeks), promoting sustained angiogenesis and anti-inflammation. Our results demonstrate that the core-shell microneedle possesses anti-inflammatory properties and can induce angiogenesis both in vitro in terms of macrophage polarization and tube formation of human umbilical vein endothelial cells (HUVECs), and in vivo in terms of anti-inflammation, re-epithelization, and vessel formation. Importantly, we also observe reduced scar formation in vivo. Altogether, the degradation dynamics of our hydrophilic/hydrophobic materials enable the design of a core-shell microneedle for differential and prolonged release, promoting scarless skin regeneration, with potential for other therapies of long-term exosome release.

Natural xanthones as modulators of the Nrf2/ARE signaling pathway and potential gastroprotective agents

Oxidative stress is implicated in the initiation, pathogenesis, and progression of various gastric inflammatory diseases (GID). The prevalence of these diseases remains a concern along with the increasing risks of adverse effects in current clinical interventions. Hence, new gastroprotective agents capable of inhibiting oxidative stress by modulating cellular defense systems such as the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway are critically needed to address these issues. A candidate to solve the present issue is xanthone, a natural compound that reportedly exerts gastroprotective effects via antioxidant, anti-inflammatory, and cytoprotective mechanisms. Moreover, xanthone derivatives were shown to modulate the Nrf2/ARE signaling pathway to counter oxidative stress in both in vitro and in vivo models. Thirteen natural xanthones have demonstrated the ability to modulate the Nrf2/ARE signaling pathway and have high potential as lead compounds for GID as indicated by their in vivo gastroprotective action-particularly mangiferin (2), α-mangostin (3), and γ-mangostin (4). Further studies on these compounds are recommended to validate the Nrf2 modulatory ability in relation to their gastroprotective action.

Helicobacter pylori infection in humans and phytotherapy, probiotics, and emerging therapeutic interventions: a review

The global prevalence of Helicobacter pylori (H. pylori) infection remains high, indicating a persistent presence of this pathogenic bacterium capable of infecting humans. This review summarizes the population demographics, transmission routes, as well as conventional and novel therapeutic approaches for H. pylori infection. The prevalence of H. pylori infection exceeds 30% in numerous countries worldwide and can be transmitted through interpersonal and zoonotic routes. Cytotoxin-related gene A (CagA) and vacuolar cytotoxin A (VacA) are the main virulence factors of H. pylori, contributing to its steep global infection rate. Preventative measures should be taken from people's living habits and dietary factors to reduce H. pylori infection. Phytotherapy, probiotics therapies and some emerging therapies have emerged as alternative treatments for H. pylori infection, addressing the issue of elevated antibiotic resistance rates. Plant extracts primarily target urease activity and adhesion activity to treat H. pylori, while probiotics prevent H. pylori infection through both immune and non-immune pathways. In the future, the primary research focus will be on combining multiple treatment methods to effectively eradicate H. pylori infection.

Role of Mangiferin in Management of Cancers through Modulation of Signal Transduction Pathways

Cancer is a major public health concern worldwide in terms of mortality. The exact reason behind the development of cancer is not understood clearly, but it is evidenced that alcohol consumption, radiation, and exposure to chemicals are main players in this pathogenesis. The current mode of treatments such as surgery, chemotherapy, and radiotherapy are effective, but, still, cancer is a major problem leading to death and other side effects. However, safer and effective treatment modules are needed to overcome the adverse effects of current treatment modules. In this regard, natural compounds have been recognized to ameliorate diseases by exerting anti-inflammatory, anti-oxidative, and anti-tumor potential through several mechanisms. Mangiferin, a xanthone C-glucoside, is found in several plant species including Mangifera indica (mango), and its role in disease prevention has been confirmed through its antioxidant and anti-inflammatory properties. Furthermore, its anti-cancer-potential mechanism has been designated through modulation of cell signaling pathways such as inflammation, angiogenesis, PI3K/AKT, apoptosis, and cell cycle. This article extensively reviews the anticancer potential of mangiferin in different cancers through the modulation of cell signaling pathways. Moreover, the synergistic effects of this compound with some commonly used anti-cancer drugs against different cancer cells are discussed. More clinical trials should be performed to reconnoiter the anti-cancer potential of this compound in human cancer treatment. Further, understanding of mechanisms of action and the safety level of this compound can help to manage diseases, including cancer.

Review of Phytochemical Potency as a Natural Anti-Helicobacter pylori and Neuroprotective Agent

Phytochemicals are plant secondary metabolites that show health benefits for humans due to their bioactivity. There is a huge variety of phytochemicals that have already been identified, and these compounds can act as antimicrobial and neuroprotection agents. Due to their anti-microbial activity and neuroprotection, several phytochemicals might have the potency to be used as natural therapeutic agents, especially for Helicobacter pylori infection and neurodegenerative disease, which have become a global health concern nowadays. According to previous research, there are some connections between H. pylori infection and neurodegenerative diseases, especially Alzheimer's disease. Hence, this comprehensive review examines different kinds of phytochemicals from natural sources as potential therapeutic agents to reduce H. pylori infection and improve neurodegenerative disease. An additional large-scale study is needed to establish the connection between H. pylori infection and neurodegenerative disease and how phytochemicals could improve this condition.

Irigenin, a novel lead from Iris confusa for management of Helicobacter pylori infection with selective COX-2 and HpIMPDH inhibitory potential

The development of new natural drugs for Helicobacter pylori (H. pylori) management has recently received significant attention. Iris confusa (I. confusa) was long used for the treatment of bacterial infections and gastritis. This study aimed at evaluating its effect on management of H. pylori infection and exploring its bioactive metabolites. The inhibitory potential of the polar (PF), non-polar (NPF) fractions and the isolated compounds against H. pylori using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay in addition to their cyclooxygenases (COX-1 and COX-2), and nitric oxide (NO) inhibitory activities were assessed. The most biologically active compound was tested for its selective H. pylori inosine-5'-monophosphate dehydrogenase (HpIMPDH) inhibitory potential. Chromatographic purification of PF and NPF allowed isolation of tectoridin, orientin, irigenin, tectorigenin, isoarborinol and stigmasterol. The PF exhibited significant anti-H. pylori (MIC 62.50 µg/mL), COX-1, COX-2 (IC50 of 112.08 ± 0.60 and 47.90 ± 1.50 µg/mL respectively, selectivity index SI of 2.34), and NO (IC50 47.80 ± 0.89 µg/mL) inhibitory activities, while irigenin was the most potent isolated compound. Irigenin was found to have a promising activity against HpIMPDH enzyme (IC50 of 2.07 ± 1.90 μM) with low activity against human hIMPDH2 (IC50 > 10 μM) than clarithromycin, assuring its selectivity. Overall, I. confusa and its isolated compounds may serve as a potential source of plant-based drugs for H. pylori control. This study scientifically validated the claimed anti-bacterial activity of I. confusa and revealed irigenin potential as a novel lead exhibiting anti H. pylori activity in a first record.

Xanthone C-glycosides isomers purified from Dryopteris ramosa (Hope) C. Chr. with bactericidal and cytotoxic prospects

Xanthones C-glycosides are plants secondary metabolites with diverse biological activities. Among the C-glycoside xanthones, the mangiferin (MF) is of widespread occurrence in plants while isomangiferin (IsoMF) is not very common. For the present study mangiferin (MF) and isomangiferin (IsoMF) were isolated from Dryopteris ramosa. The antibacterial potential of MF and IsoMF was evaluated by using agar well diffusion method while cytotoxic properties of MF and IsoMF were assessed by brine shrimp lethality test (BSLT). The antibacterial potential of MF and IsoMF increases in dose dependent manner. The minimum inhibitory concentration (MIC) indicated strong antibacterial potential of MF against Salmonella setubal (125 µg/mL) and Bacillus subtilis (125 µg/mL) while MF showed weak antibacterial potential against Escherichia coli (500 µg/mL). On the other hand the IsoMF showed better antibacterial potential against all the tested strain including Escherichia coli (MIC = 250 µg/mL). The MF and IsoMF showed poor cytotoxicity towards Brine shrimp nauplii as indicated by their LD₅₀ (969.77 ± 0.67 and 768.92 ± 0.81 µg/mL respectively). The present study has highlighted the antibacterial potential of MF and IsoMF. Further evaluation of these two isomeric compounds may prove to be the future remedies for various bacterial infections and other human ailments.

Anti-inflammatory and anti-oxidative effect of Korean propolis on Helicobacter pylori-induced gastric damage in vitro

Helicobacter pylori, present in the stomach lining, is a Gramnegative bacterium that causes various gastrointestinal diseases, including gastritis and peptic ulcers. Propolis is a natural resinous substance collected from a variety of plants, and contains several natural bioactive substances. The aim of this study was to investigate the anti-inflammatory and antioxidative effects of Korean propolis on H. pylori-induced damage in the human adenocarcinoma gastric cell line. The propolis used in this study was obtained from the Korea Beekeeping Association in South Korea. The expression of pro-inflammatory interleukins (ILs), such as IL-8, IL-12, IL-1β, tumor necrosis factor alpha, cyclooxygenase-2, and inducible nitric oxide synthase, which was increased after H. pylori infection, significantly decreased in a dose-dependent manner upon pretreatment with Korean propolis, because of the suppression of mitogen-activated protein kinases and nuclear factor kB pathway. The anti-oxidative activity of propolis was assessed using the 2,2-diphenyl-1-picrylhydrazyl hydrate free radical assay. Korean propolis showed significant anti-oxidative effects via reactive oxygen species scavenging. In addition, pretreatment with Korean propolis upregulated the expression of anti-oxidant enzymes through Nrf2 signaling activation. These findings indicate that the use of Korean propolis, which has anti-inflammatory and anti-oxidative effects, can be promising for the prevention of H. pylori-induced gastric damage.

Mangiferin enhances endochondral ossification-based bone repair in massive bone defect by inducing autophagy through activating AMP-activated protein kinase signaling pathway

Endochondral ossification is crucial for bone formation in both adult bone repair process and embryo long-bone development. In endochondral ossification, bone marrow-derived mesenchymal stem cells (BMSCs) first differentiate to chondrocytes, then BMSC-derived chondrocytes endure a hypertrophic process to generate new bone. Endochondral ossification-based bone repair is a promising strategy to cure massive bone defect, which is a major clinical issue in orthopedics. However, challenges still remain for this novel strategy. One challenge is to ensure the sufficient hypertrophic differentiation. Another is to maintain the survival of the above hypertrophic chondrocytes under the hypoxic environment of massive bone defect. To solve this issue, mangiferin (MAG) was introduced to endochondral ossification-based bone repair. In this report, we proved MAG to be a novel autophagy inducer, which promoted BMSC-derived hypertrophic chondrocyte survival against hypoxia-induced injury through inducing autophagy. Furthermore, MAG enhances hypertrophic differentiation of BMSC-derived chondrocytes via upregulating key hypertrophic markers. Mechanistically, MAG induced autophagy in BMSC-derived chondrocytes by promoting AMPKα phosphorylation. Additionally, MAG balanced the expression of sex-determining region Y-box 9 and runt-related transcription factor 2 to facilitate hypertrophic differentiation. These results indicated that MAG was a potential drug to improve the efficacy of endochondral ossification-based bone repair in massive bone defects.-Bai, Y., Liu, C., Fu, L., Gong, X., Dou, C., Cao, Z., Quan, H., Li, J., Kang, F., Dai, J., Zhao, C., Dong, S. Mangiferin enhances endochondral ossification-based bone repair in massive bone defect by inducing autophagy through activating AMP-activated protein kinase signaling pathway.