Anti-hypernociceptive effect of mangiferin in persistent and neuropathic pain models in rats

Synergistic interaction between amitriptyline and paracetamol in persistent and neuropathic pain models: An isobolografic analysis

The current study was designed to evaluate the transient antinociceptive interaction between amitriptyline and paracetamol in the formalin test. In addition, considering other long-term neuroprotective mechanisms of these drugs, we hypothesized that this combination might exert some synergistic effects on neuropathic pain linked with its possible ability to prevent Wallerian degeneration (WD). The effects of individual and fixed-ratio of 1:1 combinations of orally administered amitriptyline and paracetamol were assayed in the two phases of the formalin test and in the chronic constriction injury (CCI) model in rats. Isobolographic analysis was employed to characterize the synergism produced by the combinations. Amitriptyline, paracetamol, and fixed-ratio amitriptyline-paracetamol combinations produced dose-dependent antinociceptive effects mainly on the inflammatory tonic phase. Repeated doses of individual drugs and their combination decreased CCI-induced mechanical allodynia in a dose-dependent manner. ED₃₀ (formalin) and ED₅₀ (CCI) values were estimated for the individual drugs, and isobolograms were constructed. Theoretical ED_30/50 values for the combination estimated from the isobolograms were 16.5 ± 3.9 mg/kg and 26.0 ± 7.2 mg/kg for the single and repeated doses in persistent and neuropathic pain models, respectively. These values were significantly higher than the actually observed ED_30/50 values, which were 0.39 ± 0.1 mg/kg and 8.2 ± 0.8 mg/kg in each model, respectively, indicating a synergistic interaction. Remarkably, CCI-induced sciatic nerve WD-related histopathological changes were prevented by this combination compared to either drug administered alone.

The Traditional Uses, Phytochemistry, Pharmacology, Toxicology, and Clinical Uses of Metagentiana Rhodantha (Franch.) T.N.Ho and S.W.Liu, an Ethnomedicine in Southwest China

Background: Metagentiana rhodantha (Franch.) T.N.Ho and S.W.Liu (MR) belongs to Gentianales, and it is often called Hong-hua-long-dan in Chinese. Traditionally, it has been used to cure acute icteric hepatitis, sore throat, dysentery, acute gastritis, carbuncle, and furuncle based on traditional Chinese medicine (TCM) concepts. Aim of Study: This review manages to provide a critical and comprehensive analysis on the traditional uses, phytochemistry, pharmacology, toxicology, and clinical uses of MR and to evaluate the therapeutic potential of this plant. Methods: Relevant data mainly literatures on MR were selected from available database. All the papers reviewed provided evidence that the source herbs were reliably identified. Results: The heat-clearing and removing the phlegm, and purging fire and removing toxicity of MR contribute to its dispelling jaundice, and clearing lung heat and cough. The compounds isolated from this plant include iridoids and secoiridoids, phenolic acids, ketones, triterpenoids, flavonoids, benzophenone glycosides, and others. Mangiferin (MAF) is a characteristic substance from this plant. The pharmacological studies show that some extracts and compounds from MR exhibit anti-inflammatory, antinociceptive, antibacterial, hepatoprotective, cardioprotective, and other effects which are associated with the traditional uses of this plant. The toxicological studies suggest that MAF is less toxic in mice and dogs. Nowadays, Chinese patent drugs such as Feilike Jiaonang and Kangfuling Jiaonang containing MR have been used to cure cough, asthma, chronic bronchitis, dysmenorrhea, and appendagitis. Conclusion: Although the current studies provide related research information of MR, it is still necessary to systemically evaluate the chemistry, pharmacology, toxicity, and safety of the extracts or compounds from this plant before clinical trials in the future. In addition, except for lung infection-related diseases, analgesia, anti-tumor, and hypertriglycemia may be new and prior therapeutic scopes of this ethnomedicine in the future.

Anti-angiogenic effects of mangiferin and mechanism of action in metastatic melanoma

Advanced metastatic melanoma, one of the most aggressive skin malignancies, is currently without reliable therapy. The process of angiogenesis is crucial for progression and metastasis of the majority of solid tumors including melanomas. Therefore, new therapies are urgently needed. Mangiferin is a naturally occurring glucosylxanthone which exerts many pharmacological activities against cancer-inflammation. However, the effect of mangiferin on metastasis and tumor growth of metastatic melanoma remains unclear. In this study, we demonstrate that mangiferin interferes with inflammation, lipid and calcium signaling which selectively inhibits multiple NFkB target genes including interleukin-6, tumor necrosis factor, interferon gamma, vascular endothelial growth factor receptor 2, plasminogen activator urokinase, matrix metalloprotease 19, C-C Motif Chemokine Ligand 2 and placental growth factor. This abrogates angiogenic and invasive processes and capillary tube formation of metastatic melanoma cells as well as human placental blood vessel explants in-vitro and blocks angiogenesis characteristic of the chicken egg chorioallantoic membrane assay and in melanoma syngeneic studies in vivo. The results obtained in this research illustrate promising anti-angiogenic effects of the natural glucosylxanthone mangiferin for further (pre)clinical studies in melanoma cancer patients.

Therapeutic potential of mangiferin in the treatment of various neuropsychiatric and neurodegenerative disorders

Xanthones are important chemical class of bioactive products that confers therapeutic benefits. Of several xanthones, mangiferin is known to be distributed widely across several fruits, vegetables and medicinal plants. Mangiferin has been shown to exert neuroprotective effects in both in-vitro and in-vivo models. Mangiferin attenuates cerebral infarction, cerebral edema, lipid peroxidation (MDA), neuronal damage, etc. Mangiferin further potentiate levels of endogenous antioxidants to confer protection against the oxidative stress inside the neurons. Mangiferin is involved in the regulation of various signaling pathways that influences the production and levels of proinflammatory cytokines in brain. Mangiferin cosunteracted the neurotoxic effect of amyloid-beta, MPTP, rotenone, 6-OHDA etc and confer protection to neurons. These evidence suggested that the mangiferin may be a potential therapeutic strategy for the treatment of various neurological disorders. The present review demonstrated the pharmacodynamics-pharmacokinetics of mangiferin and neurotherapeutic potential in several neurological disorders with underlying mechanisms.

Mangiferin: Possible uses in the prevention and treatment of mixed osteoarthritic pain

Osteoarthritis (OA) pain has been proposed to be a mixed pain state, because in some patients, central nervous system factors are superimposed upon the more traditional peripheral factors. In addition, a considerable amount of preclinical and clinical evidence has shown that, accompanying the central neuroplasticity changes and partially driven by a peripheral nociceptive input, a real neuropathic component occurs that are particularly linked to disease severity and progression. Hence, innovative strategies targeting neuroprotection and particularly neuroinflammation to prevent and treat OA pain could be introduced. Mangiferin (MG) is a glucosylxanthone that is broadly distributed in higher plants, such as Mangifera indica L. Previous studies have documented its analgesic, anti-inflammatory, antioxidant, neuroprotective, and immunomodulatory properties. In this paper, we propose its potential utility as a multitargeted compound for mixed OA pain, even in the context of multimodal pharmacotherapy. This hypothesis is supported by three main aspects: the cumulus of preclinical evidence around this xanthone, some preliminary clinical results using formulations containing MG in clinical musculoskeletal or neuropathic pain, and by speculations regarding its possible mechanism of action according to recent advances in OA pain knowledge.

Mangiferin nanoemulsions in treatment of inflammatory disorders and skin regeneration

In this paper mangiferin nanoemulsions were developed using hyaluronic acid of different molecular weight, in absence or presence of Transcutol-P. An extensive study was carried out on the physico-chemical properties of nanoemulsions. Nanosizer and transmission electron microscopy showed oil droplets average size 296 nm with monodisperses distribution (PI ≤ 0.30). The zeta potential was highly negative (-30 mV). FTIR analysis confirms the existence of physical interactions among compounds. Rheological measurements allowed to conclude that all formulations present a pseudoplastic behavior (s ∼ 0.4) in presence of the biopolymer. Moreover, mangiferin release depends on the molecular weight of the polymer. Permeability assays on pig epidermis showed that nanoemulsions with low molecular weight hyaluronic acid improve the permeation, being this effect more pronounced in nanoemulsions with Transcutol-P. Administration of mangiferin nanoemulsions on TPA-inflamed skin mice model provided an attenuation of oedema and leucocyte infiltration. Macroscopic appearance of mice skin lesions has a good correlation with the histological study. The topical application of these formulations shows an appropriate anti-inflammatory effect.

Anti-allodynic Effect of Mangiferin in Rats With Chronic Post-ischemia Pain: A Model of Complex Regional Pain Syndrome Type I

The present study reproduces chronic post-ischemia pain (CPIP), a model of complex regional pain syndrome type I (CRPS-I), in rats to examine the possible transient and long-term anti-allodynic effect of mangiferin (MG); as well as its potential beneficial interactions with some standard analgesic drugs and sympathetic-mediated vasoconstriction and vasodilator agents during the earlier stage of the pathology. A single dose of MG (50 and 100 mg/kg, p.o.) decreased mechanical allodynia 72 h post-ischemia-reperfusion (I/R). MG 100 mg/kg, i.p. (pre- vs. post-drug) increased von Frey thresholds in a yohimbine and naloxone-sensitive manner. Sub-effective doses of morphine, amitriptyline, prazosin, clonidine and a NO donor, SIN-1, in the presence of MG were found to be significantly anti-allodynic. A long-term anti-allodynic effect at 7 and 13 days post-I/R after repeated oral doses of MG (50 and 100 mg/kg) was also observed. Further, MG decreased spinal and muscle interleukin-1β concentration and restored muscle redox status. These results indicate that MG has a transient and long-term anti-allodynic effect in CPIP rats that appears to be at least partially attributable to the opioid and α2 adrenergic receptors. Additionally, its anti-inflammatory and antioxidant mechanisms could also be implicated in this effect. The association of MG with sub-effective doses of these drugs enhances the anti-allodynic effect; however, an isobolographic analysis should be performed to define a functional interaction between them. These findings suggest the possible clinical use of MG in the treatment of CRPS-I in both early sympathetically maintained pain and long-term sympathetically independent pain.

Synergistic Interaction of a Gabapentin- Mangiferin Combination in Formalin-Induced Secondary Mechanical Allodynia and Hyperalgesia in Rats Is Mediated by Activation of NO-Cyclic GMP-ATP-Sensitive K+ Channel Pathway

Preclinical Research Gabapentin is an anticonvulsant used to treat neuropathic pain. Mangiferin is an antioxidant that has antinociceptive and antiallodynic effects in inflammatory and neuropathic pain models. The purpose of this study was to determine the interaction between mangiferin and gabapentin in the development and maintenance of formalin-induced secondary allodynia and hyperalgesia in rats. Gabapentin, mangiferin, or their fixed-dose ratio combination were administrated peripherally. Isobolographic analyses was used to define the nature of the interaction of antiallodynic and/or antihyperalgesic effects of the two compounds. Theoretical ED₅₀ values for the combination were 74.31 µg/paw and 95.20 µg/paw for pre- and post-treatment, respectively. These values were higher than the experimental ED₅₀ values, 29.45 µg/paw and 37.73 µg/paw respectively, indicating a synergistic interaction in formalin-induced secondary allodynia and hyperalgesia. The antiallodynic and antihyperalgesic effect induced by the gabapentin/mangiferin combination was blocked by administration of L-NAME, the soluble guanylyl cyclase inhibitor, ODQ and glibenclamide. These data suggest that the gabapentin- mangiferin combination produces a synergistic interaction at the peripheral level. Moreover, the antiallodynic and hyperalgesic effect induced by the combination is mediated via the activation of an NO-cyclic GMP-ATP-sensitive K⁺ channel pathway. Drug Dev Res 78 : 390-402, 2017. © 2017 Wiley Periodicals, Inc.

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.

Anti-allodynic effect of mangiferin in neuropathic rats: Involvement of nitric oxide-cyclic GMP-ATP sensitive K+ channels pathway and serotoninergic system

The neurobiology of neuropathic pain is caused by injury in the central or peripheral nervous system. Recent evidence points out that mangiferin shows anti-nociceptive effect in inflammatory pain. However, its role in inflammatory and neuropathic pain and the possible mechanisms of action are not yet established. The purpose of this study was to determine the possible anti-allodynic effect of mangiferin in rats with spinal nerve ligation (SNL). Furthermore, we sought to investigate the possible mechanisms of action that contribute to these effects. Mechanical allodynia to stimulation with the von Frey filaments was measured by the up and down method. Intrathecal administration of mangiferin prevented, in a dose-dependent fashion, SNL-induced mechanical allodynia. Mangiferin-induced anti-allodynia was prevented by the intrathecal administration of L-NAME (100μg/rat, non-selective nitric oxide synthase inhibitor), ODQ (10μg/rat, inhibitor of guanylate-cyclase) and glibenclamide (50μg/rat, channel blocker of ATP-sensitive K⁺ channels). Moreover, methiothepin (30μg/rat, non-selective 5-HT receptor antagonist), WAY-100635 (6μg/rat, selective 5-HT_1A receptor antagonist), SB-224289 (5μg/rat, selective 5-HT_1B receptor antagonist), BRL-15572 (4μg/rat, selective 5-HT_1D receptor antagonist) and SB-659551 (6μg/rat, selective 5-HT_5A receptor antagonist), but not naloxone (50μg/rat, non-selective opioid receptor antagonist), were able to prevent mangiferin-induced anti-allodynic effect. These data suggest that the anti-allodynic effect induced by mangiferin is mediated at least in part by the serotoninergic system, involving the activation of 5-HT_1A/1B/1D/5A receptors, as well as the nitric oxide-cyclic GMP-ATP-sensitive K⁺ channels pathway, but not by the opioidergic system, in the SNL model of neuropathic pain in rats.

Endogenous opiates and behavior: 2014

This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants). This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants).

Identification of target proteins of mangiferin in mice with acute lung injury using functionalized magnetic microspheres based on click chemistry

Prevention of the occurrence and development of inflammation is a vital therapeutic strategy for treating acute lung injury (ALI). Increasing evidence has shown that a wealth of ingredients from natural foods and plants have potential anti-inflammatory activity. In the present study, mangiferin, a natural C-glucosyl xanthone that is primarily obtained from the peels and kernels of mango fruits and the bark of the Mangifera indica L. tree, alleviated the inflammatory responses in lipopolysaccharide (LPS)-induced ALI mice. Mangiferin-modified magnetic microspheres (MMs) were developed on the basis of click chemistry to capture the target proteins of mangiferin. Mass spectrometry and molecular docking identified 70 kDa heat-shock protein 5 (Hspa5) and tyrosine 3-monooxygenase (Ywhae) as mangiferin-binding proteins. Furthermore, an enzyme-linked immunosorbent assay (ELISA) indicated that mangiferin exerted its anti-inflammatory effect by binding Hspa5 and Ywhae to suppress downstream mitogen-activated protein kinase (MAPK) signaling pathways. Thoroughly revealing the mechanism and function of mangiferin will contribute to the development and utilization of agricultural resources from M. indica L.