Mangiferin induces apoptosis by suppressing Bcl-xL and XIAP expressions and nuclear entry of NF-κB in HL-60 cells

Mangiferin: A natural bioactive immunomodulating glucosylxanthone with potential against cancer and rheumatoid arthritis

Mangiferin is a naturally occurring glucosylxanthone that has shown promising immunomodulatory effects. It is generally isolated from the leaves, peels, bark, and kernels of Mangifera indica Linn. Mangiferin is like a miraculous natural bioactive molecule that has an immunomodulatory function that makes it a potential therapeutic candidate for the treatment of rheumatoid arthritis (RA) and cancer. The anticancer activity of mangiferin acts by blocking NF-κB, as well as regulating the β-catenin, EMT, MMP9, MMP2, LDH, ROS, and NO, and also by the activation of macrophages. It has no cytotoxic effect on grown chondrocytes and lowers matrix metalloproteinase levels. Additionally, it has a potent proapoptotic impact on synoviocytes. The precise molecular mechanism of action of mangiferin on RA and malignancies is still unknown. This comprehensive review elaborates on the immunomodulatory effect of mangiferin and its anticancer and anti-RA activity. This also explained the total synthesis of mangiferin and its in vitro and in vivo screening models.

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.

Nanotechnology-Based Drug Delivery Approaches of Mangiferin: Promises, Reality and Challenges in Cancer Chemotherapy

Mangiferin (MGF), a xanthone derived from Mangifera indica L., initially employed as a nutraceutical, is now being explored extensively for its anticancer potential. Scientists across the globe have explored this bioactive for managing a variety of cancers using validated in vitro and in vivo models. The in vitro anticancer potential of this biomolecule on well-established breast cancer cell lines such as MDA-MB-23, BEAS-2B cells and MCF-7 is closer to many approved synthetic anticancer agents. However, the solubility and bioavailability of this xanthone are the main challenges, and its oral bioavailability is reported to be less than 2%, and its aqueous solubility is also 0.111 mg/mL. Nano-drug delivery systems have attempted to deliver the drugs at the desired site at a desired rate in desired amounts. Many researchers have explored various nanotechnology-based approaches to provide effective and safe delivery of mangiferin for cancer therapy. Nanoparticles were used as carriers to encapsulate mangiferin, protecting it from degradation and facilitating its delivery to cancer cells. They have attempted to enhance the bioavailability, safety and efficacy of this very bioactive using drug delivery approaches. The present review focuses on the origin and structure elucidation of mangiferin and its derivatives and the benefits of this bioactive. The review also offers insight into the delivery-related challenges of mangiferin and its applications in nanosized forms against cancer. The use of a relatively new deep-learning approach to solve the pharmacokinetic issues of this bioactive has also been discussed. The review also critically analyzes the future hope for mangiferin as a therapeutic agent for cancer management.

Phytochemicals: A potential next generation agent for radioprotection

BACKGROUND

Radiation hazards are accountable for extensive damage in the biological system and acts as a public health burden. Owing to the rapid increasing in radiation technology, both Ionizing radiation (IR) from natural and man made source poses detrimental outcome to public health. IR releases free radicals which induces oxidative stress and deleterious biological damage by modulating radiation induced signalling intermediates. The efficacy of existing therapeutic approach and treatment strategy are limited owing to their toxicity and associated side effects. Indian system of traditional medicine is enriched with prospective phytochemicals with potential radioprotection ability.

PURPOSE

The present review elucidated and summarized the potential role of plant derived novel chemical compound with prospective radioprotective potential.

METHOD

So far as the traditional system of Indian medicine is concerned, plant kingdom is enriched with potential bioactive molecules with diverse pharmacological activities. We reviewed several compounds mostly secondary metabolites from plant origin using various search engines.

RESULTS

Both compounds from land plants and marine source exhibited antioxidant antiinflammatory, free radical scavenging ability. These compounds have tremendous potential in fine-tuning of several signalling intermediates, which are actively participated in the progression and development of a pathological condition associated with radiation stress.

CONCLUSION

Development and explore of an operational radioprotective agent from originated from plant source that can be used as a novel molecular tool to eliminate the widespread damage caused by space exploration, ionizing radiation, nuclear war and radiotherapy has been significantly appreciated. Through extensive literature search we highlighted several compounds from both land plant and marine origin can be implemented for a better therapeutic potential against radiation induced injury. Furthermore, extensive clinical trials must be carried out in near future for better therapeutic modality and clinical efficacy.

Mangiferin as New Potential Anti-Cancer Agent and Mangiferin-Integrated Polymer Systems-A Novel Research Direction

For a long time, the pharmaceutical industry focused on natural biologically active molecules due to their unique properties, availability and significantly less side-effects. Mangiferin is a naturally occurring C-glucosylxantone that has substantial potential for the treatment of various diseases thanks to its numerous biological activities. Many research studies have proven that mangiferin possesses antioxidant, anti-infection, anti-cancer, anti-diabetic, cardiovascular, neuroprotective properties and it also increases immunity. It is especially important that it has no toxicity. However, mangiferin is not being currently applied to clinical use because its oral bioavailability as well as its absorption in the body are too low. To improve the solubility, enhance the biological action and bioavailability, mangiferin integrated polymer systems have been developed. In this paper, we review molecular mechanisms of anti-cancer action as well as a number of designed polymer-mangiferin systems. Taking together, mangiferin is a very promising anti-cancer molecule with excellent properties and the absence of toxicity.

Xanthones and Cancer: from Natural Sources to Mechanisms of Action

Xanthones are a class of heterocyclic natural products that have been widely studied for their pharmacological potential. In fact, they have been serving as scaffolds for the design of derivatives focusing on drug development. One of the main study targets of xanthones is their anticancer activity. Several compounds belonging to this class have already demonstrated cytotoxic and antitumor effects, making it a promising group for further exploration. This review therefore focuses on recently published studies, emphasizing their natural and synthetic sources and describing the main mechanisms of action responsible for the anticancer effect of promising xanthones.

Polyphenolic Characterization, Antioxidant, and Cytotoxic Activities of Mangifera indica Cultivars from Costa Rica

The phenolic profile of skin and flesh from Manifera indica main commercial cultivars (Keitt and Tommy Atkins) in Costa Rica was studied using ultra performance liquid chromatography coupled with high resolution mass spectrometry (UPLC-ESI-MS) on enriched phenolic extracts. A total of 71 different compounds were identified, including 32 gallates and gallotannins (of different polymerization degree, from galloyl hexose monomer up to decagalloyl hexoses and undecagalloyl hexoses); seven hydroxybenzophenone (maclurin and iriflophenone) derivatives, six xanthonoids (including isomangiferin and mangiferin derivatives); 11 phenolic acids (hydroxybenzoic and hydroxycinnamic acid derivatives); and eight flavonoids (rhamnetin and quercetin derivatives). The findings for T. Atkins skin constitute the first report of such a high number and diversity of compounds. Also, it is the first time that the presence of gallotannin decamers and undecamers are reported in the skin and flesh of Keitt cultivar and in T. Atkins skins. In addition, total phenolic content (TPC) was measured with high values especially for fruits' skins, with a TPC of 698.65 and 644.17 mg gallic acid equivalents/g extract, respectively, for Keitt and T. Atkins cultivars. Antioxidant potential using 2,2-diphenyl-1-picrylhidrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) methods were evaluated, with T. Atkins skin showing the best values for both DPPH (IC₅₀ = 9.97 µg/mL) and ORAC (11.02 mmol TE/g extract). A significant negative correlation was found for samples between TPC and DPPH antioxidant values (r = -0.960, p < 0.05), as well as a significant positive correlation between TPC and ORAC (r = 0.910, p < 0.05) and between DPPH and ORAC antioxidant methods (r = 0.989, p < 0.05). Also, cytotoxicity was evaluated in gastric adenocarcinoma (AGS), hepatocarcinoma (HepG2), and colon adenocarcinoma (SW620), with T. Atkins skin showing the best results (IC₅₀ = 138-175 µg/mL). Finally, for AGS and SW 620 cell lines particularly, a high significant negative correlation was found between cytotoxic activity and gallotannins (r = -0.977 and r = -0.940, respectively) while for the HepG2 cell line, the highest significant negative correlation was found with xanthonoids compounds (r = -0.921).

Improving the biopharmaceutical attributes of mangiferin using vitamin E-TPGS co-loaded self-assembled phosholipidic nano-mixed micellar systems

The current research work encompasses the development, characterization, and evaluation of self-assembled phospholipidic nano-mixed miceller system (SPNMS) of a poorly soluble BCS Class IV xanthone bioactive, mangiferin (Mgf) functionalized with co-delivery of vitamin E TPGS. Systematic optimization using I-optimal design yielded self-assembled phospholipidic nano-micelles with a particle size of < 60 nm and > 80% of drug release in 15 min. The cytotoxicity and cellular uptake studies performed using MCF-7 and MDA-MB-231 cell lines demonstrated greater kill and faster cellular uptake. The ex vivo intestinal permeability revealed higher lymphatic uptake, while in situ perfusion and in vivo pharmacokinetic studies indicated nearly 6.6- and 3.0-folds augmentation in permeability and bioavailability of Mgf. In a nutshell, vitamin E functionalized SPNMS of Mgf improved the biopharmaceutical performance of Mgf in rats for enhanced anticancer potency.

Suppression of IKK, but not activation of p53 is responsible for cell death mediated by naturally occurring oxidized tetranortriterpenoid

Tetranortriterpenoids (limonoids) obtained from the neem tree (Azadirachta indica) have gained significant attention due to their anti-proliferative properties. Here we are investigating the role of a highly oxidized tetranortriterpenoid, azadirachtin on induction of the cell death. Using various apoptotic assays, we show that azadirachtin induces cell death independent of cell types. Although azadirachtin-treated cells show increased expression of p53, but no phosphorylation of p53 (at Ser15 and Ser46) is detected. In silico analysis reveals that azadirachtin interacts with Mdm2 in the p53 binding site, postulating the mutually exclusive interaction of p53 and azadirachtin with Mdm2. Surprisingly, azadirachtin potentiates cell death efficiently in both p53 wild-type and p53 negative cells. In addition, we find azadirachtin suppresses nuclear transcription factor kappaB (NF-κB) by inhibiting the phosphorylation of upstream inhibitory subunit of NF-κB (IκB) kinase (IKK). Further, azadirachtin is unable to potentiate apoptosis in NF-κB-downregulated (IκB-DN) cells, whereas ectopic expression of p65 rescues azadirachtin-mediated apoptosis, regardless of their p53 status. Hence, our data suggest that azadirachtin mediates cell death through inhibition of NF-κB, but not due to the activation of p53. In conclusion, this study proposes azadirachtin as a potential therapeutic agent where insensitivity toward chemotherapy occurs due to the inactivation or mutations in p53.

Mangiferin prevents the growth of gastric carcinoma by blocking the PI3K-Akt signalling pathway

The aim of the present study was to investigate the effects of mangiferin on gastric carcinoma cells and to determine the possible mechanisms underlying such effects. The MTT assay was performed to evaluate the antiproliferative effect of mangiferin. Following treatment, apoptosis rates of SGC-7901 were established by flow cytometry and laser confocal microscopy, and western blot analysis was used to detect the expression of apoptosis-related proteins. The MTT assay showed that mangiferin inhibited the proliferation of SGC-7901 and BCG-823 cells in a dose-dependent and time-dependent manner. After SGC-7901 cells were exposed to mangiferin for 24, 48 and 72 h, the half-maximal inhibitory concentration values were 16.00, 8.63 and 4.79 µmol/l, respectively. SGC-7901 cell apoptosis induced by mangiferin was observed by Annexin V/PI doubling staining and terminal deoxynucleotidyl transferase dUTP nick end labeling-positive staining. We found a significant decrease in Bcl-2, Bcl-xL and Mcl-1 expression and a significant increase in Bax, Bad and cleaved caspase-3 and caspase-9 expression in SGC-7901 cells by mangiferin treatment. Moreover, mangiferin significantly decreased the levels of p-PI3K, p-Akt and p-mTOR, but had no effects on those of PI3K, Akt and mTOR in epidermal growth factor-treated SGC-7901 cells. Interestingly, the proapoptotic effect of mangiferin on SGC-7901 cells was partially blocked by the Akt activator SC79, whereas LY294002 significantly increased mangiferin-induced apoptosis and growth inhibition. Taken together, our findings indicate that mangiferin effectively inhibits cell growth and induces apoptosis of gastric cancer cells through inhibiting the PI3K/Akt pathways with relative safety, and may be used as a novel chemotherapeutic agent against gastric cancer.

The effect of mangiferin on skin: Penetration, permeation and inhibition of ECM enzymes

Mangiferin (2-C-β-D-glucopyranosyl-1,3,6,7-tetrahydroxyxanthone) is a polyphenol with strong antioxidant properties. Mangiferin is obtained from the mango tree (Mangifera indica L., Anacardiaceae). It has been proven that mangiferin exhibits many pharmacological activities. The aim of this study was to analyze the penetration of mangiferin into the human skin and through the skin. According to our knowledge, skin penetration and permeation studies of mangiferin have not been analyzed so far. Additionally, the influence of mangiferin on two Extracellular Matrix Enzymes (ECM): collagenase and elastase, was evaluated for the first time. It has been indicated that mangiferin is able to permeate the stratum corneum and penetrate into the epidermis and dermis in comparable amounts. For confirmation of the obtained results, fluorescence microscopy was successfully utilized. The analysis revealed the capability of mangiferin to reversibly inhibit elastase and collagenase activity. The mechanism of mangiferin interaction with both enzymes was estimated as a noncompetitive inhibition.

In Vitro Comparative Study of the Inhibitory Effects of Mangiferin and Its Aglycone Norathyriol towards UDP-Glucuronosyl Transferase (UGT) Isoforms

Mangiferin (MGF), the predominant constituent of extracts of the mango plant Mangifera Indica L., has been investigated extensively because of its remarkable pharmacological effects. In vitro recombinant UGTs-catalyzed glucuronidation of 4-methylumbelliferone (4-MU) was used to investigate the inhibition of mangiferin and aglycone norathyriol towards various isoforms of UGTs in our study, which evaluated the inhibitory capacity of MGF and its aglycone norathyriol (NTR) towards UDP-glucuronosyltransferase (UGT) isoforms. Initial screening experiment showed that deglycosylation of MGF into NTR strongly increased the inhibitory effects towards almost all the tested UGT isoforms at a concentration of 100 μM. Kinetic experiments were performed to further characterize the inhibition of UGT1A3, UGT1A7 and UGT1A9 by NTR. NTR competitively inhibited UGT1A3, UGT1A7 and UGT1A9, with an IC₅₀ value of 8.2, 4.4, and 12.3 μM, and a Ki value of 1.6, 2.0, and 2.8 μM, respectively. In silico docking showed that only NTR could dock into the activity cavity of UGT1A3, UGT1A7 and UGT1A9. The binding free energy of NTR to UGT1A3, 1A7, 1A9 were −7.4, −7.9 and −4.0 kcal/mol, respectively. Based on the inhibition evaluation standard ([I]/Ki < 0.1, low possibility; 0.1 < [I]/Ki < 1, medium possibility; [I]/Ki > 1, high possibility), an in vivo herb–drug interaction between MGF/NTR and drugs mainly undergoing UGT1A3-, UGT1A7- or UGT1A9-catalyzed metabolism might occur when the plasma concentration of NTR is above 1.6, 2.0 and 2.8 μM, respectively.

Mangiferin: a natural miracle bioactive compound against lifestyle related disorders

The current review article is an attempt to explain the therapeutic potential of mangiferin, a bioactive compound of the mango, against lifestyle-related disorders. Mangiferin (2-β-D-glucopyranosyl-1,3,6,7-tetrahydroxy-9H-xanthen-9-one) can be isolated from higher plants as well as the mango fruit and their byproducts (i.e. peel, seed, and kernel). It possesses several health endorsing properties such as antioxidant, antimicrobial, antidiabetic, antiallergic, anticancer, hypocholesterolemic, and immunomodulatory. It suppresses the activation of peroxisome proliferator activated receptor isoforms by changing the transcription process. Mangiferin protects against different human cancers, including lung, colon, breast, and neuronal cancers, through the suppression of tumor necrosis factor α expression, inducible nitric oxide synthase potential, and proliferation and induction of apoptosis. It also protects against neural and breast cancers by suppressing the expression of matrix metalloproteinase (MMP)-9 and MMP-7 and inhibiting enzymatic activity, metastatic potential, and activation of the β-catenin pathway. It has the capacity to block lipid peroxidation, in order to provide a shielding effect against physiological threats. Additionally, mangiferin enhances the capacity of the monocyte-macrophage system and possesses antibacterial activity against gram-positive and gram-negative bacteria. This review summarizes the literature pertaining to mangiferin and its associated health claims.

Mangiferin: A xanthonoid with multipotent anti-inflammatory potential

Over the last era, small molecules sourced from different plants have gained attention for their varied and long-term medicinal benefits. Their advantageous therapeutic effects in diverse pathological complications lead researchers to give an ever-increasing emphasis on them and discover their novel therapeutic potentials. Among these, the heat stable, xanthonoid group of organic molecules has gained special importance with distinctive regards to the bioactive molecule mangiferin due to its solubility in water. Mangiferin, a yellow polyphenol having C-glycosyl xanthone structure, is widely present in different edible sources like mango, and possesses numerous biological activities. Extensive research with this molecule shows its antioxidant, anti-inflammatory, antidiabetic, anticancer, antimicrobial, analgesic, and immunomodulatory properties. Thus, it provides protection against a wide range of physiological disorders. The C-glucosyl linkage and polyhydroxy groups in mangiferin's structure contribute essentially to its free radical-scavenging activity. Moreover, its ability in regulating various transcription factors like NF-κB, Nrf-2, etc. and modulating the expression of different proinflammatory signaling intermediates like tumor necrosis factor-α, COX-2, etc. contribute to its anti-inflammatory, anticancer, and antidiabetic potentials. In this comprehensive article, information has been provided about the sources, chemical structure, metabolism, and different biological activities of mangiferin with special emphasis on the underlying cellular signal transduction pathways. Insights into an in-depth assessment of mangiferin's anti-inflammatory therapeutic potential have also been discussed in detail. On an overall perspective, this review aims to stage mangiferin's diversified therapeutic applications and its emerging possibility as a promising drug in future based on its anti-inflammatory property. © 2016 BioFactors, 42(5):459-474, 2016.

The potential role of mangiferin in cancer treatment through its immunomodulatory, anti-angiogenic, apoptopic, and gene regulatory effects

Mangiferin (1,3,6,7-tetrahydroxyxanthone-C2-β-D-glucoside) is a natural bioactive xanthonoid that can be found in many plant species, among which the mango tree (Mangifera indica L), a plant widely used in the traditional medicinal, is one of its primary sources. The use of mangiferin for cancer treatment has attracted the attention of research groups around the World. Single administration of mangiferin or in combination with known anticancer chemicals has shown the potential benefits of this molecule in lung, brain, breast, cervix, and prostate cancers, and leukemia. Mangiferin mechanisms of action against cancer cells through in vitro, ex vivo, or in vivo models are discussed besides its antioxidant and anti-inflammatory properties. Nevertheless, pharmaceutical development and, therefore, clinical trials on cancer targets are still lacking. © 2016 BioFactors, 42(5):475-491, 2016.

Mangiferin, a novel nuclear factor kappa B-inducing kinase inhibitor, suppresses metastasis and tumor growth in a mouse metastatic melanoma model

Advanced metastatic melanoma, one of the most aggressive malignancies, is currently without reliable therapy. Therefore, new therapies are urgently needed. Mangiferin is a naturally occurring glucosylxanthone and exerts many beneficial biological activities. However, the effect of mangiferin on metastasis and tumor growth of metastatic melanoma remains unclear. In this study, we evaluated the effect of mangiferin on metastasis and tumor growth in a mouse metastatic melanoma model. We found that mangiferin inhibited spontaneous metastasis and tumor growth. Furthermore, mangiferin suppressed the nuclear translocation of nuclear factor kappa B (NF-κB) and expression of phosphorylated NF-κB-inducing kinase (NIK), inhibitor of kappa B kinase (IKK), and inhibitor of kappa B (IκB) and increases the expression of IκB protein in vivo. In addition, we found that mangiferin inhibited the expression of matrix metalloproteinases (MMPs) and very late antigens (VLAs) in vivo. Mangiferin treatment also increased the expression of cleaved caspase-3, cleaved Poly ADP ribose polymerase-1 (PARP-1), p53 upregulated modulator of apoptosis (PUMA), p53, and phosphorylated p53 proteins, and decreased the expression of Survivin and Bcl-associated X (Bcl-xL) proteins in vivo. These results indicate that mangiferin selectivity suppresses the NF-κB pathway via inhibition of NIK activation, thereby inhibiting metastasis and tumor growth. Importantly, the number of reported NIK selective inhibitors is limited. Taken together, our data suggest that mangiferin may be a potential therapeutic agent with a new mechanism of targeting NIK for the treatment of metastatic melanoma.

Differential genotoxicity and cytotoxicity of phomoxanthone A isolated from the fungus Phomopsis longicolla in HL60 cells and peripheral blood lymphocytes

Phomoxanthone A (PhoA) is a compound isolated from the endophytic fungus Phomopsis longicolla, associated with marine algae Bostrychia radicans. Although this metabolite was previously described regarding its high biological potential, there are no reports concerning the effects of this compound on DNA integrity. This study aimed to evaluate, in lymphocytes and promyelocytic leukemia HL60 cells, the cytotoxicity of this compound through MTT and neutral red (NR) assays, as well as its genotoxicity and mutagenicity by alkaline comet assay and cytokinesis-block micronucleus cytome assay (CBMN-Cyt), respectively. Cells were treated with PhoA concentrations ranging from 0.01 to 100.0μg/mL, and the results show that this molecule did not exhibit cytotoxicity, genotoxicity or mutagenicity in lymphocytes at any tested concentration. Furthermore, PhoA was highly cytotoxic, genotoxic and mutagenic to HL60 cells, establishing a differential response of this natural product in normal and cancer cells. PhoA was highly selective towards HL60 compared to lymphocytes, causing no damage in the latter cell line, suggesting that this compound could be a promising compound in antitumoral drug development.

Mangiferin: a promising anticancer bioactive

Of late, several biologically active antioxidants from natural products have been investigated by the researchers in order to combat the root cause of carcinogenesis, in other words, oxidative stress. Mangiferin, a therapeutically active C-glucosylated xanthone, is extracted from pulp, peel, seed, bark and leaf of Mangifera indica. These polyphenols of mangiferin exhibit antioxidant properties and tend to decrease the oxygen-free radicals, thereby reducing the DNA damage. Indeed, its capability to modulate several key inflammatory pathways undoubtedly helps in stalling the progression of carcinogenesis. The current review article emphasizes an updated account on the patents published on the chemopreventive action of mangiferin, apoptosis induction made on various cancer cells, along with proposed antioxidative activities and patent mapping of other important therapeutic properties. Considering it as promising polyphenol, this paper would also summarize the diverse molecular targets of mangiferin.

Mangiferin enhances the sensitivity of human multiple myeloma cells to anticancer drugs through suppression of the nuclear factor κB pathway

Multiple myeloma (MM) is still an incurable hematological malignancy with a 5-year survival rate of ~35%, despite the use of various treatment options. The nuclear factor κB (NF-κB) pathway plays a crucial role in the pathogenesis of MM. Thus, inhibition of the NF-κB pathway is a potential target for the treatment of MM. In a previous study, we showed that mangiferin suppressed the nuclear translocation of NF-κB. However, the treatment of MM involves a combination of two or three drugs. In this study, we examined the effect of the combination of mangiferin and conventional anticancer drugs in an MM cell line. We showed that the combination of mangiferin and an anticancer drug decreased the viability of MM cell lines in comparison with each drug used separately. The decrease in the combination of mangiferin and an anticancer drug induced cell viability was attributed to increase the expression of p53 and Noxa and decreases the expression of XIAP, survivin, and Bcl-xL proteins via inhibition of NF-κB pathway. In addition, the combination treatment caused the induction of apoptosis, activation of caspase-3 and the accumulation of the cells in the sub-G1 phase of the cell cycle. Our findings suggest that the combination of mangiferin and an anticancer drug could be used as a new regime for the treatment of MM.

Mangiferin induces apoptosis in multiple myeloma cell lines by suppressing the activation of nuclear factor kappa B-inducing kinase

Mangiferin is a naturally occurring glucosyl xanthone, which induces apoptosis in various cancer cells. However, the molecular mechanism underlying mangiferin-induced apoptosis has not been clarified thus far. Therefore, we examined the molecular mechanism underlying mangiferin-induced apoptosis in multiple myeloma (MM) cell lines. We found that mangiferin decreased the viability of MM cell lines in a concentration-dependent manner. We also observed an increased number of apoptotic cells, caspase-3 activation, and a decrease in the mitochondrial membrane potential. In addition, mangiferin inhibited the nuclear translocation of nuclear factor kappa B (NF-κB) and expression of phosphorylated inhibitor kappa B (IκB) and increased the expression of IκB protein, whereas no changes were observed in the phosphorylation levels of extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal protein kinase 1/2 (JNK1/2), and mammalian target of rapamycin (mTOR). The molecular mechanism responsible for mangiferin-induced inhibition of nuclear translocation of NF-κB was a decrease in the expression of phosphorylated NF-κB-inducing kinase (NIK). Moreover, mangiferin decreased the expression of X-linked inhibitor of apoptosis protein (XIAP), survivin, and Bcl-xL proteins. Knockdown of NIK expression showed results similar to those observed with mangiferin treatment. Our results suggest that mangiferin induces apoptosis through the inhibition of nuclear translocation of NF-κB by suppressing NIK activation in MM cell lines. Our results provide a new insight into the molecular mechanism of mangiferin-induced apoptosis. Importantly, since the number of reported NIK inhibitors is limited, mangiferin, which targets NIK, may be a potential anticancer agent for the treatment of MM.

Mangiferin protect myocardial insults through modulation of MAPK/TGF-β pathways

Mangiferin, a xanthone glycoside isolated from leaves of Mangifera indica (Anacardiaceae) is known to modulate many biological targets in inflammation and oxidative stress. The present study was designed to investigate whether mangiferin exerts protection against myocardial ischemia-reperfusion (IR) injury and possible role of Mitogen Activated Protein Kinase (MAPKs) and Transforming Growth Factor-β (TGF-β) pathways in its cardioprotection. Male albino Wistar rats were treated with mangiferin (40 mg/kg, i.p.) for 15 days. At the end of the treatment protocol, rats were subjected to IR injury consisting of 45 min ischemia followed by 1h reperfusion. IR-control rats caused significant cardiac dysfunction, increased serum cardiac injury markers, lipid peroxidation and a significant decrease in tissue antioxidants as compared to sham group. Histopathological examination of IR rats revealed myocardial necrosis, edema and infiltration of inflammatory cells. However, pretreatment with mangiferin significantly restored myocardial oxidant-antioxidant status, maintained membrane integrity, and attenuated the levels of proinflammatory cytokines, pro-apoptotic proteins and TGF-β. Furthermore, mangiferin significantly reduced the phosphorylation of p38, and JNK and enhanced phosphorylation of ERK1/2. These results suggest that mangiferin protects against myocardial IR injury by modulating MAPK mediated inflammation and apoptosis.

Mangiferin blocks proliferation and induces apoptosis of breast cancer cells via suppression of the mevalonate pathway and by proteasome inhibition

Mangiferin is a natural xanthone glycoside with therapeutic potential.

Mangiferin activates the Nrf2-ARE pathway and reduces etoposide-induced DNA damage in human umbilical cord mononuclear blood cells

CONTEXT

Mangiferin (2-C-β-d-gluco-pyranosyl-1,3,6,7-tetrahydroxyxanthone) is a well-known natural antioxidant distributed in various plants of the Anacardiaceae and Gentianaceae families. Mangiferin can inhibit carcinogen-induced lung or colon tumor formation in experimental animals. However, the molecular mechanisms of its chemopreventive activity remain unexplored.

OBJECTIVE

This study aimed to investigate the effects of mangiferin on chemical carcinogen-induced DNA damage and Nrf2-ARE signaling in hematopoietic cells.

MATERIALS AND METHODS

Mononuclear cells (MNCs) were isolated from human umbilical cord blood (hUCB). DNA damage was evaluated by comet and micronucleus assays. The expression of Nrf2 and NQO1 was examined by immunofluorescence and western blotting. An electrophoretic mobility shift assay (EMSA) was used to detect the binding activity of Nrf2 with NQO1-ARE sequences.

RESULTS

We found that mangiferin treatment significantly reduced DNA damage in etoposide-treated MNCs, which was verified by decreased olive tail moment (OTM) and micronucleus (MN) frequency. Mangiferin treatment significantly promoted Nrf2 translocation into the nucleus and increased nuclear Nrf2 expression. Moreover, NQO1, an Nrf2 signaling target, was significantly upregulated by mangiferin treatment, and the binding activity of Nrf2 with NQO1-ARE sequences was elevated after mangiferin treatment.

DISCUSSION AND CONCLUSION

Mangiferin activated Nrf2 signaling, upregulated NQO1 expression, and significantly reduced etoposide-induced DNA damage. Thus, mangiferin is a potential cytoprotective agent for hematopoietic cells.

Antidiabetic potential of some less commonly used plants in traditional medicinal systems of India and Nigeria

The incidence of diabetes mellitus continue to rise annually all over the world with India and Nigeria having recorded cases of 65.1 and 3.9 million respectively in 2013 and expected to increase by a large amount in 2035. Hyperglycemia is a pre-condition for the development of diabetic complications and is accompanied by an increase in the production of free radicals. The present available treatment option for diabetes like sulfonylurea, metformin and alpha-glucosidase are restricted by their limited actions, secondary failure rates, and side-effects; and unaffordable to the majority of the population. Hence, the need to screen for more medicinal plants with antidiabetic ability due to the fact that plants are; biodegradable, safe and cheap with fewer side-effects. In this review article, we have presented the current status of diabetes in India and Nigeria and the role of some less commonly used medicinal plants from both countries that have antidiabetic potential.

Mangiferin induces cell death against rhabdomyosarcoma through sustained oxidative stress

BACKGROUND

Embryonic rhabdomyosarcoma (RD) is the most prevalent type of cancer among children. The present study aimed to investigate cell death induced by mangiferin in RD cells.

METHODS

The Inhibitory concentration (IC₅₀) value of mangiferin was determined by an MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay. Cell death induced by mangiferin against RD cells was determined through lactate dehydrogenase and nitric oxide release, intracellular calcium levels, reactive oxygen species generation, antioxidant status, mitochondrial calcium level, and mitochondrial membrane potential. Furthermore, acridine orange/ethidium bromide staining was performed to determine early/late apoptotic event.

RESULTS

Mangiferin induced cell death in RD cells with an IC₅₀ value of 70 μM. The cytotoxic effect was reflected in a dose-dependent increase in lactate dehydrogenase leakage and nitric oxide release during mangiferin treatment. Mangiferin caused dose dependent increase in reactive oxygen species generation, intracellular calcium levels with subsequent decrease in antioxidant status (catalase, superoxide dismutase, glutathione-S-transferase, and glutathione) and loss of mitochondrial membrane potential in RD cells. Further data from fluorescence microscopy suggest that mangiferin caused cell shrinkage and nuclear condensation along with the occurrence of a late event of apoptosis.

CONCLUSION

Results of the present study shows that mangiferin can act as a promising chemopreventive agent against RD by inducing sustained oxidative stress.

Dimethyl fumarate induces apoptosis of hematopoietic tumor cells via inhibition of NF-κB nuclear translocation and down-regulation of Bcl-xL and XIAP

Dimethyl fumarate (DMF) is a fumaric acid ester that is used to treat psoriasis and multiple sclerosis. Recently, DMF was found to exhibit anti-tumor effects. However, the molecular mechanisms underlying these effects have not been elucidated. In this study, we investigated the mechanism of DMF-induced apoptosis in different human hematopoietic tumor cell lines. We found that DMF induced apoptosis in different human hematopoietic tumor cell lines but it did not affect the normal human B lymphocyte cell line RPMI 1788. We also observed a concurrent increase in caspase-3 activity and in the number of Annexin-V-positive cells. Furthermore, an examination of the survival signals, which are activated by apoptotic stimuli, revealed that DMF significantly inhibited nuclear factor-κB (NF-κB) p65 nuclear translocation. In addition, DMF suppressed B-cell lymphoma extra-large (Bcl-xL) and X-linked inhibitor of apoptosis (XIAP) expression whereas Bcl-2, survivin, Bcl-2-associated X protein (Bax), and Bim levels did not change. These results indicated that DMF induced apoptosis by suppressing NF-κB activation, and Bcl-xL and XIAP expression. These findings suggested that DMF might have potential as an anticancer agent that could be used in combination therapy with other anticancer drugs for the treatment of human hematopoietic tumors.

Mangiferin has an additive effect on the apoptotic properties of hesperidin in Cyclopia sp. tea extracts

A variety of biological pro-health activities have been reported for mangiferin and hesperidin, two major phenolic compounds of Honeybush (Cyclopia sp.) tea extracts. Given their increasing popularity, there is a need for understanding the mechanisms underlying the biological effects of these compounds. In this study, we used real-time cytotoxicity cellular analysis of the Cyclopia sp. extracts on HeLa cells and found that the higher hesperidin content in non-fermented "green" extracts correlated with their higher cytotoxicity compared to the fermented extracts. We also found that mangiferin had a modulatory effect on the apoptotic effects of hesperidin. Quantitative PCR analysis of hesperidin-induced changes in apoptotic gene expression profile indicated that two death receptor pathway members, TRADD and TRAMP, were up regulated. The results of this study suggest that hesperidin mediates apoptosis in HeLa cells through extrinsic pathway for programmed cell death.

Mangiferin activates Nrf2-antioxidant response element signaling without reducing the sensitivity to etoposide of human myeloid leukemia cells in vitro

AIM

Mangiferin is glucosylxanthone extracted from plants of the Anacardiaceae and Gentianaceae families. The aim of this study was to investigate the effects of mangiferin on Nrf2-antioxidant response element (ARE) signaling and the sensitivity to etoposide of human myeloid leukemia cells in vitro.

METHODS

Human HL-60 myeloid leukemia cells and mononuclear human umbilical cord blood cells (MNCs) were examined. Nrf2 protein was detected using immunofluorescence staining and Western blotting. Binding of Nrf2 to ARE was examined with electrophoretic mobility shift assay. The level of NQO1 was assessed with real-time RT-PCR and Western blotting. DCFH-DA was used to evaluate intracellular ROS level. Cell proliferation and apoptosis were analyzed using MTT and flow cytometry, respectively.

RESULTS

Mangiferin (50 μmol/L) significantly increased Nrf2 protein accumulation in HL-60 cells, particularly in the nucleus. Mangiferin also enhanced the binding of Nrf2 to an ARE, significantly up-regulated NQO1 expression and reduced intracellular ROS in HL60 cells. Mangiferin alone dose-dependently inhibited the proliferation of HL-60 cells. Mangiferin (50 mol/L) did not attenuate etoposide-induced cytotoxicity in HL-60 cells, and combined treatment of mangiferin with low concentration of etoposide (0.8 μg/mL) even increased the cell inhibition rate. Nor did mangiferin change the rate of etoposide-induced apoptosis in HL-60 cells. In MNCs, mangiferin significantly relieved oxidative stress, but attenuated etoposide-induced cytotoxicity.

CONCLUSION

Mangiferin is a novel Nrf2 activator that reduces oxidative stress and protects normal cells without reducing the sensitivity to etoposide of HL-60 leukemia cells in vitro. Mangiferin may be a potential chemotherapy adjuvant.

Therapeutic and cosmetic applications of mangiferin: a patent review

INTRODUCTION

Mangiferin, a natural C-glucoside xanthone [2-C-β-D-glucopyranosyl-1, 3, 6, 7-tetrahydroxyxanthone], is abundantly present in young leaves and stem bark of the mango tree. The xanthonoid structure of mangiferin with C-glycosyl linkage and polyhydroxy components contributes to its free radical-scavenging ability, leading to a potent antioxidant effect as well as multiple biological activities.

AREAS COVERED

An extensive search was carried out to collect patent information on mangiferin and its derivatives using various patent databases spanning all priority years to date. The patents claiming therapeutic and cosmetic applications of mangiferin and its derivatives were analyzed in detail. The technology areas covered in this article include metabolic disorders, cosmeceuticals, multiple uses of the same compound, miscellaneous uses, infectious diseases, inflammation, cancer and autoimmune disorders, and neurological disorders.

EXPERT OPINION

Mangiferin has the potential to modulate multiple molecular targets including nuclear factor-kappa B (NF-κB) signaling and cyclooxygenase-2 (COX-2) protein expression. Mangiferin exhibits antioxidant, antidiabetic, antihyperuricemic, antiviral, anticancer and antiinflammatory activities. The molecular structure of mangiferin fulfils the four Lipinski's requisites reported to favor high bioavailability by oral administration. There is no evidence of adverse side effects of mangiferin so far. Mangiferin could thus be a promising candidate for development of a multipotent drug.

Synthesis and biological evaluation of Germanium(IV)-polyphenol complexes as potential anti-cancer agents

Germanium (Ge) is considered to play a key role in the pharmacological effects of some medicinal plants. Here, two new Ge(IV)-polyphenol complexes were synthesized and measured for their potential biological activities. The results indicated that these Ge(IV)-polyphenol complexes possessed great anti-oxidative activities, both showing stronger hydroxyl scavenging effects than their corresponding ligands. We also demonstrated the strong intercalating abilities of Ge(IV)-polyphenol complexes into calf thymus-DNA molecules. In addition, these two Ge(IV)-polyphenol complexes showed strong proliferative inhibition effect on HepG2 cancer cells. Moreover, the morphological changes in HepG2 cells induced by Ge(IV)-polyphenol complexes were detected by atomic force microscopy. All these results collectively suggested that Ge(IV)-polyphenol complexes could be served as promising pharmacologically active substances against cancer treatment.

Metabolism and pharmacokinetics of mangiferin in conventional rats, pseudo-germ-free rats, and streptozotocin-induced diabetic rats

To clarify the role of the intestinal flora in the absorption and metabolism of mangiferin and to elucidate its metabolic fate and pharmacokinetic profile in diabetic rats, a systematic and comparative investigation of the metabolism and pharmacokinetics of mangiferin in conventional rats, pseudo-germ-free rats, and streptozotocin (STZ)-induced diabetic rats was conducted. Forty-eight metabolites of mangiferin were detected and identified in the urine, plasma, and feces after oral administration (400 mg/kg). Mangiferin underwent extensive metabolism in conventional rats and diabetic rats, but the diabetic rats exhibited a greater number of metabolites compared with that of conventional rats. When the intestinal flora were inhibited, deglycosylation of mangiferin and sequential biotransformations would not occur. Pharmacokinetic studies indicated a 2.79- and 2.35-fold increase in the plasma maximum concentration and the area under the concentration-time curve from 0 to 24 h of mangiferin in diabetic rats compared with those for conventional rats, whereas no significant differences were observed between conventional rats and pseudo-germ-free rats. Further real-time quantitative reverse transcription-polymerase chain reaction results indicated that the multidrug resistance (mdr) 1a level in the ileum increased, whereas its level in the duodenum and the mdr1b mRNA levels in the duodenum, jejunum, and ileum decreased in diabetic rats compared with those in conventional rats. With regard to the pseudo-germ-free rats, up-regulated mdr1a mRNA levels and down-regulated mdr1b mRNA levels in the small intestines were observed. The diabetic status induced increased UDP-glucuronosyltransferase (UGT) 1A3, UGT1A8, UGT2B8, and sulfotransferase (SULT) 1A1 mRNA levels and decreased catechol-O-methyltransferase (COMT), UGT2B6, UGT2B12, and SULT1C1 mRNA levels. These results might partially explain the different pharmacokinetic and metabolic disposition of mangiferin among conventional and model rats.

The pyranoxanthone inophyllin A induces oxidative stress mediated-apoptosis in Jurkat T lymphoblastic leukemia cells

Inophyllin A (INO-A), a pyranoxanthone isolated from the roots of Calophyllum inophyllum represents a new xanthone with potential chemotherapeutic activity. In this study, the molecular mechanism of INO-A-induced cell death was investigated in Jurkat T lymphoblastic leukemia cells. Assessment of phosphatidylserine exposure confirmed apoptosis as the primary mode of cell death in INO-A-treated Jurkat cells. INO-A treatment for only 30 min resulted in a significant increase of tail moment which suggests that DNA damage is an early apoptotic signal. Further flow cytometric assessment of the superoxide anion level confirmed that INO-A induced DNA damage was mediated with a concomitant generation of reactive oxygen species (ROS). Investigation on the thiols revealed an early decrease of free thiols in 30 min after 50 μM INO-A treatment. Using tetramethylrhodamine ethyl ester, a potentiometric dye, the loss of mitochondrial membrane potential (MPP) was observed in INO-A-treated cells as early as 30 min. The INO-A-induced apoptosis progressed with the simultaneous activation of caspases-2 and -9 which then led to the processing of caspase-3. Taken together, these data demonstrate that INO-A induced early oxidative stress, DNA damage and loss of MMP which subsequently led to the activation of an intrinsic pathway of apoptosis in Jurkat cells.

Antiproliferative effect of alpinetin in BxPC-3 pancreatic cancer cells

Alpinetin is a novel plant flavonoid derived from Alpinia katsumadai Hayata, found to possess strong anticancer effects. However, the antitumor effect of alpinetin on pancreatic cancer cells and the detailed mechanism remain unclear. The aim of this study was to investigate alpinetin's beneficial effect on pancreatic cancer and the possible molecular mechanism involved. Pancreatic cancer cell lines were treated with alpinetin at various doses and for different times, and the effect of alpinetin on cell growth inhibition, apoptosis and the cell cycle was determined. The expression of Bcl-2, Bcl-xL, XIAP and Bax, the activity of caspases and the levels of cytochrome c released were measured. The results showed that alpinetin inhibited the viability of three pancreatic cancer cell lines and induced apoptosis of BxPC-3 cells in a dose- and time-dependent manner. This was accompanied by regulation of the expression of Bcl-2, Bcl-xL, Bax and XIAP. Furthermore, alpinetin treatment led to the release of cytochrome c and activation of caspases-3, -8 and -9 proteins. Taken together, our studies indicate that alpinetin inhibited the proliferation of pancreatic cancer cells possibly through the regulation of the Bcl-2 family and XIAP expression, release of cytochrome c and the activation of caspases. Alpinetin may serve as a potential agent for the development of pancreatic cancer cell therapies.