Cytoprotective Effects of Mangiferin and Z-Ligustilide in PAH-Exposed Human Airway Epithelium in Vitro

Therapeutic potential of mangiferin in cancer: Unveiling regulatory pathways, mechanisms of action, and bioavailability enhancements - An updated review

Mangiferin (MGF) is a phenolic compound, which is a major source of MGF is the mango tree. MGF possesses some antioxidant, anti-inflammatory, and cytoprotective properties, enabling it to play its role against various diseases such as diabetes, obesity, lung injuries, and cancer. The word "Cancer" depicts an uncontrolled and abnormal growth of cells. This review paper reveals MGF's therapeutic, curative and protective potential impact against lung, liver, ovarian, prostate, breast, stomach, and oral cancers. MGF is used in various types of research in the form of powder, liquid extract, intramuscular, intravenous, nanoparticles coated with gold, in the form of a solution, or in combination with other drugs to evaluate synergistic effects. Many studies showed that MGF is safe to use but has less bioavailability in the body and 0.111 mg/mL solubility in water. However, certain studies indicated that its bioavailability and retention time increased when taken in the form of nanoparticles and in combination with other drugs. MGF also increases the sensitivity of other drugs (i.e., cisplatin) resistant to tumors. MGF has different mechanisms of action for different cancers. It mainly targets enzymes, interleukins, tumor growth factors, signaling pathways, apoptotic proteins, and genes to inhibit the growth of tumors, volume, angiogenesis, cellular functionality, further progression, and movement to other areas of the body. Moreover, MGF increases apoptosis and body weight with no or fewer side effects on normal cells. MGF unveiled a novel gate toward the treatment of cancer. Further research and human trials are needed in this regard.

Acetylcholinesterase Inhibitors in the Treatment of Neurodegenerative Diseases and the Role of Acetylcholinesterase in their Pathogenesis

Acetylcholinesterase (AChE) plays an important role in the pathogenesis of neurodegenerative diseases by influencing the inflammatory response, apoptosis, oxidative stress and aggregation of pathological proteins. There is a search for new compounds that can prevent the occurrence of neurodegenerative diseases and slow down their course. The aim of this review is to present the role of AChE in the pathomechanism of neurodegenerative diseases. In addition, this review aims to reveal the benefits of using AChE inhibitors to treat these diseases. The selected new AChE inhibitors were also assessed in terms of their potential use in the described disease entities. Designing and searching for new drugs targeting AChE may in the future allow the discovery of therapies that will be effective in the treatment of neurodegenerative diseases.

Environmental toxicants, oxidative stress and health adversities: interventions of phytochemicals

OBJECTIVES

Oxidative stress is the most common factor mediating environmental chemical-induced health adversities. Recently, an exponential rise in the use of phytochemicals as an alternative therapeutics against oxidative stress-mediated diseases has been documented. Due to their free radical quenching property, plant-derived natural products have gained substantial attention as a therapeutic agent in environmental toxicology. The present review aimed to describe the therapeutic role of phytochemicals in mitigating environmental toxicant-mediated sub-cellular and organ toxicities via controlling cellular antioxidant response.

METHODS

The present review has covered the recently related studies, mainly focussing on the free radical scavenging role of phytochemicals in environmental toxicology.

KEY FINDINGS

In vitro and in vivo studies have reported that supplementation of antioxidant-rich compounds can ameliorate the toxicant-induced oxidative stress, thereby improving the health conditions. Improving the cellular antioxidant pool has been considered as a mode of action of phytochemicals. However, the other cellular targets of phytochemicals remain uncertain.

CONCLUSIONS

Knowing the therapeutic value of phytochemicals to mitigate the chemical-induced toxicity is an initial stage; mechanistic understanding needs to decipher for development as therapeutics. Moreover, examining the efficacy of phytochemicals against mixer toxicity and identifying the bioactive molecule are major challenges in the field.

Advances in Pharmacological Actions and Mechanisms of Flavonoids from Traditional Chinese Medicine in Treating Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a common respiratory disease with high morbidity and mortality. The conventional therapies remain palliative and have various undesired effects. Flavonoids from traditional Chinese medicine (TCM) have been proved to exert protective effects on COPD. This review aims to illuminate the poly-pharmacological properties of flavonoids in treating COPD based on laboratory evidences and clinical data and points out possible molecular mechanisms. Animal/laboratory studies and randomised clinical trials about administration of flavonoids from TCM for treating COPD from January 2010 to October 2020 were identified and collected, with the following terms: chronic obstructive pulmonary disease or chronic respiratory disease or inflammatory lung disease, and flavonoid or nature product or traditional Chinese medicine. Pharmacokinetic studies and external application treatment were excluded. A total of 15 flavonoid compounds were listed. Flavonoids could inhibit inflammation, oxidative stress, and cellular senescence, restore corticosteroid sensitivity, improve pulmonary histology, and boost pulmonary function through regulating multiple targets and signaling pathways, which manifest that flavonoids are a group of promising natural products for COPD. Nevertheless, most studies remain in the research phase of animal testing, and further clinical applications should be carried out.

Mangiferin Rich Products from Aphloia theiformis (Vahl) Benn Leaves: Extraction, Fractionation, Phytochemical Characterization, and Antioxidant Properties

Aphloia theiformis is traditionally used in Mauritius, Madagascar, and Reunion Island for treating several diseases. In this study, various extraction solvents and schemes were applied for the recovery of antioxidant rich fractions from the leaves of A. theiformis. The products were evaluated for their antioxidant capacity using well known in vitro assays. Major compounds were characterized by UPLC–QTOF–MS. Hydrophilic extracts of A. theiformis demonstrated strong antioxidant properties, which are comparable with the synthetic antioxidant Trolox. UPLC analysis confirmed mangiferin as the main secondary metabolite of A. theiformis. Tormentic and hydroxytormentic acids as well as their isomers were also abundant in A. theiformis extracts and fractions, while their amounts were determined for the first time. The most potential extract was further separated into the fractions by liquid-liquid extraction and by precipitation at low temperature. Antioxidant capacity and composition of secondary metabolites of derived fractions were determined. Some of the fractions possessed remarkable antioxidant capacity, comparable to pure mangiferin. The results obtained reveal high potential of A. theiformis for recovery of natural antioxidants and other bioactive phytochemicals, particularly mangiferin.

Mangiferin-Loaded Polymeric Nanoparticles: Optical Characterization, Effect of Anti-topoisomerase I, and Cytotoxicity

Mangiferin is an important xanthone compound presenting various biological activities. The objective of this study was to develop, characterize physicochemical properties, and evaluate the anti-topoisomerase activity of poly(lactic-co-glycolic acid) (PLGA) nanoparticles containing mangiferin. The nanoparticles were developed by the emulsion solvent evaporation method and the optimal formulation was obtained with a response surface methodology (RSM); this formulation showed a mean size of 176.7 ± 1.021 nm with a 0.153 polydispersibility index (PDI) value, and mangiferin encapsulation efficiency was about 55%. The optimal conditions (6000 rpm, 10 min, and 300 μg of mangiferin) obtained 77% and the highest entrapment efficiency (97%). The in vitro release profile demonstrated a gradual release of mangiferin from 15 to 180 min in acidic conditions (pH 1.5). The fingerprint showed a modification in the maximum absorption wavelength of both the polymer and the mangiferin. Results of anti-toposiomerase assay showed that the optimal formulation (MG4, 25 µg/mL) had antiproliferative activity. High concentrations (2500 µg/mL) of MG4 showed non-in vitro cytotoxic effect on BEAS 2B and HEPG2. Finally, this study showed an encapsulation process with in vitro gastric digestion resistance (1.5 h) and without interfering with the metabolism of healthy cells and their biological activity.

Effects of Pyrene on Human Liver HepG2 Cells: Cytotoxicity, Oxidative Stress, and Transcriptomic Changes in Xenobiotic Metabolizing Enzymes and Inflammatory Markers with Protection Trial Using Lycopene

Pyrene is one of the major polycyclic aromatic hydrocarbons formed during heat treatment of meat and in car exhausts; however, few studies have investigated pyrene-induced adverse effects on human cell lines. This study aimed at the investigation of pyrene-induced cytotoxicity and oxidative damage in human liver HepG2 cells at environmentally relevant concentrations. Pyrene-induced changes in mRNA expression of xenobiotic metabolizing enzymes (XMEs), xenobiotic transporters, antioxidant enzymes, and inflammatory markers were investigated using real-time PCR. As a protection trial, the ameliorative effects of lycopene, a carotenoid abundantly found in tomato, were investigated. The possible mechanisms behind such effects were examined via studying the co exposure effects of pyrene and lycopene on regulatory elements including the aryl hydrocarbon receptor (Air) and elytroid 2-related factor 2 (RF). The achieved results indicated that pyrene caused significant cytotoxicity at 50 n, with a clear production of reactive oxygen species (ROS) in a dose-dependent manner. Pyrene upregulated mRNA expression of phase I enzymes including CYP1A1, 1A2, and CYP1B1 and inflammatory markers including TNFα and Cox2. However, pyrene significantly downregulated phase II enzymes, xenobiotic transporters, and antioxidant enzymes. Interestingly, lycopene significantly reduced pyrene-induced cytotoxicity and ROS production. Moreover, lycopene upregulated detoxification and antioxidant enzymes, probably via its regulatory effects on Air- and RF-dependent pathways.