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 ß-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.

Activation of STING in pancreatic cancer-associated fibroblasts exerts an antitumor effect by enhancing tumor immunity.

Pancreatic ductal adenocarcinoma (PDAC) has a high mortality rate; therefore, the development of effective treatments is a priority. The stimulator of interferon genes (STING) pathway enhances tumor immunity by inducing the production of type 1 interferon (IFN) and proinflammatory cytokines and chemokines and promoting the infiltration of cytotoxic T cells. To assess the function of STING on pancreatic tumorigenesis, Ptf1aER-Cre/+ LSL-KrasG12D/+ p53loxP/loxP mice (KPC mice) and Ptf1aER-Cre/+ LSL-KrasG12D/+ p53loxP/loxP/STING-/- mice (KPCS mice) were generated. However, STING deletion did not affect pancreatic tumorigenesis in mice. Because STING is expressed not only in immune cells but also in cancer-associated fibroblasts (CAFs), we evaluated the STING function in PDAC CAFs. A mouse STING agonist 5,6-Dimethyl-9-oxo-9H-xanthene-4-acetic acid (DMXAA) was administered to KPC mice and CAFs from KPC mice and the resulting immune response was evaluated. DMXAA activated STING in PDAC CAFs in KPC mice, promoting cytotoxic T cell infiltration by secreting proinflammatory cytokines and enhancing tumor immunity. We next generated STING-deficient PDAC cells and subcutaneous tumors in which STING was expressed only in CAFs by performing bone marrow transplantation and assessed the antitumor effect of STING-activated CAFs. The administration of DMXAA to subcutaneous tumors expressing STING only in CAFs sustained the antitumor effect of DMXAA. About half of human PDACs lacked STING expression in the cancer stroma, suggesting that STING activation in PDAC CAFs exerts an antitumor effect, and STING agonists can be more effective in tumors with high than in those with low STING expression in the stroma.

Formulation of 1% α-mangostin in orabase gel induces apoptosis in oral squamous cell carcinoma.

BACKGROUND: Plant-derived compounds have chemopreventive properties to be used as alternative medicine. Pericarp of Mangosteen (Garcinia mangostana Linn.), a tropical fruit in Southeast Asia contains a phytochemical α-mangostin (α-MG) that demonstrates potent anticancer effects against various types of cancer. α-MG has been reported to be the most effective agent in human cancer cell lines. The objectives of this study were to develop oral gel formulations containing α-MG and determine their (1) anticancer activity, (2) anti-HPV-16 and antimicrobial activities, (3) nitric oxide (NO) inhibitory activity, and (4) wound healing effect. METHODS: Formulations of oral gel containing α-MG were developed. Anticancer activity on SCC-25 was assessed. Apoptotic induction was determined using flow cytometry technique. Antiviral activity against HPV-16 pseudovirus and antimicrobial activity against S. mutans, P. gingivalis and C. albicans were investigated. NO inhibition was carried out. Fibroblast cell migration was determined by in vitro scratch assay. RESULTS: The formulation of 1% α-MG in orabase gel demonstrated anticancer activity by promoting apoptosis in SCC-25. The induction of apoptotic activity was dose dependent with pronounced effect in late apoptosis. The formulation appeared to reduce cell viability of oral keratinocytes (OKC). At CC50 it showed an inhibition against HPV-16 pseudovirus infection. The formulation had no antimicrobial activity against S. mutans, P. gingivalis and C. albicans. No significant NO inhibitory activity and wound healing effects were found. CONCLUSIONS: 1% α-MG in orabase gel exhibited anticancer activity by inducing apoptosis although low level of cytotoxicity observed in OKC was present. The appropriate carrier for novel nano-particles targeting cancer cells should be further investigated.

Photophysical Characterization and In Vitro Evaluation of α-Mangostin-Loaded HDL Mimetic Nano-Complex in LN-229 Glioblastoma Spheroid Model.

Cytotoxic activity has been reported for the xanthone α-mangostin (AMN) against Glioblastoma multiforme (GBM), an aggressive malignant brain cancer with a poor prognosis. Recognizing that AMN's high degree of hydrophobicity is likely to limit its systemic administration, we formulated AMN using reconstituted high-density lipoprotein (rHDL) nanoparticles. The photophysical characteristics of the formulation, including fluorescence lifetime and steady-state anisotropy, indicated that AMN was successfully incorporated into the rHDL nanoparticles. To our knowledge, this is the first report on the fluorescent characteristics of AMN with an HDL-based drug carrier. Cytotoxicity studies in a 2D culture and 3D spheroid model of LN-229 GBM cells and normal human astrocytes showed an enhanced therapeutic index with the rHDL-AMN formulation compared to the unincorporated AMN and Temozolomide, a standard GBM chemotherapy agent. Furthermore, treatment with the rHDL-AMN facilitated a dose-dependent upregulation of autophagy and reactive oxygen species generation to a greater extent in LN-229 cells compared to astrocytes, indicating the reduced off-target toxicity of this novel formulation. These studies indicate the potential therapeutic benefits to GBM patients via selective targeting using the rHDL-AMN formulation.

Mechanism of mangiferin in the treatment of oral submucous fibrosis based on Gene Expression Omnibus database chip mining combined with network pharmacology and molecular docking.

OBJECTIVES: This study aims to investigate the primary target and potential mechanism of mangiferin (MF) in treating oral submucous fibrosis (OSF) through Gene Expression Omnibus (GEO) database chip mining, network pharmacology, and molecular docking techniques. METHODS: Potential therapeutic targets for OSF were identified using GEO chip data. The potential targets of MF were predicted, and disease-related targets for OSF were collected from databases. A Venn diagram was created using the EVenn platform to identify overlapping targets. The protein-protein interaction (PPI) network was constructed using the STRING database. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed using the DAVID platform. Cytoscape 3.10.1 software was used to visualize a drug-target-pathway-disease network, while AutoDocktools 1.5.6 software was employed for molecular docking analysis. RESULTS: A total of 356 potential targets for MF and 360 disease-related targets for OSF were obtained from multiple databases. The top 15 key target proteins in the PPI network were selected as significant candidates. GO function and KEGG pathway enrichment analyses revealed that MF treatment primarily involved advanced glycation end products-receptor (AGE-RAGE), epidermal growth factor receptor (EGFR), and other signaling pathways associated with OSF pathogenesis. Molecular docking analysis demonstrated that MF exhibited a strong binding activity toward AKT serine kinase 1 (AKT1), tumor necrosis factor (TNF), and other core targets. CONCLUSIONS: These findings suggest that MF may exert its therapeutic effects on OSF through a multitarget approach involving various signaling pathways.

α-Mangostin reduces hypertension in spontaneously hypertensive rats and inhibits EMT and fibrosis in Ang II-induced HK-2 cells.

Hypertension affects a large number of individuals globally and is a common cause of nephropathy, stroke, ischaemic heart disease and other vascular diseases. While many anti-hypertensive medications are used safely and effectively in clinic practice, controlling hypertensive complications solely by reducing blood pressure (BP) can be challenging. α-Mangostin, a xanthone molecule extracted from the pericarp of Garcinia mangostana L., has shown various beneficial effects such as anti-tumor, anti-hyperuricemia, and anti-inflammatory properties. However, the effects of α-Mangostin on hypertension remain unknown. In this study, we observed that α-Mangostin significantly decreased systolic and diastolic blood pressure in spontaneously hypertensive rats (SHR), possibly through the down-regulation of angiotensin II (Ang II). We also identified early markers of hypertensive nephropathy, including urinary N-acetyl-ß-D-glucosaminidase (NAG) and ß2-microglobulin (ß2-MG), which were reduced by α-Mangostin treatment. Mechanistic studies suggested that α-Mangostin may inhibit renal tubular epithelial-to-mesenchymal transformation (EMT) by down-regulating the TGF-ß signaling pathway, thus potentially offering a new therapeutic approach for hypertension and hypertensive nephropathy.

Deciphering molecular mechanisms underlying the inhibition of ß-glucuronidase by xanthones from Centaurium spicatum.

Herein, we scrutinized the inhibitory potential of five xanthones and a flavonoid, sourced from Centaurium spicatum, against ß-glucuronidase activity. The results showed that gentisin and azaleatin emerged as the most potent inhibitors, with significantly lower IC50 values of 0.96 ± 0.10 and 0.57 ± 0.04 µM, respectively. The evaluation of enzyme kinetics unveiled that the isolated xanthones manifested inhibition of ß-glucuronidase through a mixed inhibition mode, whereas azaleatin exhibited a noncompetitive inhibition mechanism. The findings from molecular docking analysis unveiled that the compounds under investigation, particularly azaleatin, displayed comparatively diminished binding affinities towards ß-glucuronidase. Furthermore, the tested drugs were shown to occupy a common binding site as the employed reference drug. Our comprehensive Molecular Dynamics (MD) simulations analysis revealed consistent trajectories for the investigated drugs, wherein azaleatin and gentisin demonstrated notable stabilization of energy levels. Analysis of various MD parameters revealed that drugs with the lowest IC50 values maintained relatively stable interactions with ß-glucuronidase. These drugs were shown to exert notable alterations in their conformation or flexibility upon complexation with the target enzyme. Conversely, the flexibility and accessibility of ß-glucuronidase was reduced upon drug binding, particularly with azaleatin and gentisin, underscoring the stability of the drug-enzyme complexes. Analysis of Coul-SR and LJ-SR interaction energies unveiled consistent and stable interactions between certain isolated drugs and ß-glucuronidase. Azaleatin notably displayed the lowest average Coul-SR interaction energy, suggesting strong electrostatic interactions with the enzyme's active site and significant conformational variability during simulation. Remarkably, LJ-SR interaction energies across different xanthones complexes were more negative than their Coul-SR counterparts, emphasizing the predominant role of van der Waals interactions, encompassing attractive dispersion and repulsive forces, in stabilizing the drug-enzyme complexes rather than electrostatic interactions.

Gambogic Acid Improves Cisplatin Resistance of Bladder Cancer Cells through the Epithelial-Mesenchymal Transition Pathway Mediated by the miR-205-5p/ZEB1 Axis.

OBJECTIVE: Bladder cancer (BC) is primarily treated with cisplatin-based chemotherapy, but the development of cisplatin resistance often leads to BC recurrence. This study is focused on assessing the potential of gambogic acid (GA) in mitigating BC cells' cisplatin resistance, along with an analysis of the underlying mechanism involved. METHODS: Cisplatin was administered to human bladder transitional cell carcinoma cells (T24) at various concentration gradients to induce cisplatin-resistant (T24-DDP) cells. Several experimental groups were set: T24 group, T24-DDP group, T24-DDP+DDP group, T24-DDP+GA group, T24-DDP+DDP+GA group, T24-DDP+DDP+GA+miR-NC group, and T24-DDP+DDP+GA+miR-205-5p inhibitor group. The cell counting kit-8 (CCK-8) assay, Transwell migration assay, and scratch assay were respectively carried out for assessment of cell proliferation, invasion, and migration. Western blot analysis was conducted for detection of the protein expression of E-cadherin, ZEB1, Vimentin, N-cadherin, LRP, MRP, and P-gp in the cells, while the relative expression level of miR-205-5p was determined by qRT-PCR. RESULTS: In comparison with the T24-DDP group, cells in the T24-DDP+GA group showed enhanced sensitivity to cisplatin. Furthermore, as indicated by CCK-8 assay, GA improved T24-DDP cells' sensitivity to cisplatin, potentiated the effects of cisplatin, and exerted an inhibitory effect on the invasion, proliferation, as well as migration of T24-DDP cells. Through Western blot analysis, GA was revealed to significantly inhibit the expression of N-cadherin, E-cadherin, and Vimentin, as well as that of cisplatin-resistant proteins MRP, P-gp, and LRP in BC cells. In addition, shown by further experiments, GA promoted miR-205-5p expression and simultaneously inhibited ZEB1 expression within the cells. CONCLUSION: GA alleviates BC cells' cisplatin resistance through the epithelial-mesenchymal transition pathway mediated by the miR-205-5p/ZEB1 axis.

Antiplasmodial potential of isolated xanthones from Mesua ferrea Linn. roots: an in vitro and in silico molecular docking and pharmacokinetics study.

BACKGROUND: Malaria is a major global health concern, particularly in tropical and subtropical countries. With growing resistance to first-line treatment with artemisinin, there is an urgent need to discover novel antimalarial drugs. Mesua ferrea Linn., a plant used in traditional medicine for various purposes, has previously been investigated by our research group for its cytotoxic properties. The objective of this study was to explore the compounds isolated from M. ferrea with regards to their potential antiplasmodial activity, their interaction with Plasmodium falciparum lactate dehydrogenase (PfLDH), a crucial enzyme for parasite survival, and their pharmacokinetic and toxicity profiles. METHODS: The isolated compounds were assessed for in vitro antiplasmodial activity against a multidrug-resistant strain of P. falciparum K1 using a parasite lactate dehydrogenase (pLDH) assay. In vitro cytotoxicity against Vero cells was determined using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The interactions between the isolated compounds and the target enzyme PfLDH were investigated using molecular docking. Additionally, pharmacokinetic and toxicity properties were estimated using online web tools SwissADME and ProTox-II, respectively. RESULTS: Among the seven compounds isolated from M. ferrea roots, rheediachromenoxanthone (5), which belongs to the pyranoxanthone class, demonstrated good in vitro antiplasmodial activity, with the IC50 being 19.93 µM. Additionally, there was no toxicity towards Vero cells (CC50 = 112.34 µM) and a selectivity index (SI) of 5.64. Molecular docking analysis revealed that compound (5) exhibited a strong binding affinity of - 8.6 kcal/mol towards PfLDH and was stabilized by forming hydrogen bonds with key amino acid residues, including ASP53, TYR85, and GLU122. Pharmacokinetic predictions indicated that compound (5) possessed favorable drug-like properties and desired pharmacokinetic characteristics. These include high absorption in the gastrointestinal tract, classification as a non-substrate of permeability glycoprotein (P-gp), non-inhibition of CYP2C19, ease of synthesis, a high predicted LD50 value of 4,000 mg/kg, and importantly, non-hepatotoxic, non-carcinogenic, and non-cytotoxic effects. CONCLUSIONS: This study demonstrated that compounds isolated from M. ferrea exhibit activity against P. falciparum. Rheediachromenoxanthone has significant potential as a scaffold for the development of potent antimalarial drugs.

ß-Mangostin targets and suppresses glioma via STING activation and tumor-associated microglia polarization.

Glioma, a common and highly malignant central nervous system tumor, markedly influences patient prognosis via interactions with glioma-associated macrophages. Previous research has revealed the anticancer potential of ß-mangostin, a xanthone derivative obtained from the mangosteen fruit. This research investigated the role of ß-mangostin on microglia in the glioma microenvironment and evaluated the efficacy of ß-mangostin combined with anti-PD-1 antibody (αPD-1) in glioma-bearing mice. The results showed that, ß-mangostin attenuated M2 polarization in BV2 cells and promoted M1-related interleukin (IL)-1ß and IL-6 secretion, thereby inhibiting glioma invasion. In addition, ß-mangostin improved the anti-glioma effects of αPD-1 and increased CD8+T cell and M1-type microglia infiltration. Mechanistically, ß-mangostin bound to the stimulator of interferon genes (STING) protein, which is crucial for the anti-tumor innate immune response, and promoted STING phosphorylation in microglia, both in vivo and in vitro. These results provide insights into its mode of action and supporting further investigation into ß-mangostin as a therapeutic agent.

pH/GSH dual-responsive nanoparticle for auto-amplified tumor therapy of breast cancer.

Breast cancer remains a malignancy that poses a serious threat to human health worldwide. Chemotherapy is one of the most widely effective cancer treatments in clinical practice, but it has some drawbacks such as poor targeting, high toxicity, numerous side effects, and susceptibility to drug resistance. For auto-amplified tumor therapy, a nanoparticle designated GDTF is prepared by wrapping gambogic acid (GA)-loaded dendritic porous silica nanoparticles (DPSNs) with a tannic acid (TA)-Fe(III) coating layer. GDTF possesses the properties of near-infrared (NIR)-enhanced and pH/glutathione (GSH) dual-responsive drug release, photothermal conversion, GSH depletion and hydroxyl radical (·OH) production. When GDTF is exposed to NIR laser irradiation, it can effectively inhibit cell proliferation and tumor growth both in vitro and in vivo with limited toxicity. This may be due to the synergistic effect of enhanced tumor accumulation, and elevated reactive oxygen species (ROS) production, GSH depletion, and TrxR activity reduction. This study highlights the enormous potential of auto-amplified tumor therapy.

The total xanthones extracted from Gentianella acuta alleviates HFpEF by activating the IRE1α/Xbp1s pathway.

Heart failure with preserved ejection fraction (HFpEF) is a clinical syndrome characterized by pulmonary and systemic congestion resulting from left ventricular diastolic dysfunction and increased filling pressure. Currently, however, there is no evidence on effective pharmacotherapy for HFpEF. In this study, we aimed to investigate the therapeutic effect of total xanthones extracted from Gentianella acuta (TXG) on HFpEF by establishing an high-fat diet (HFD) + L-NAME-induced mouse model. Echocardiography was employed to assess the impact of TXG on the cardiac function in HFpEF mice. Haematoxylin and eosin staining, wheat germ agglutinin staining, and Masson's trichrome staining were utilized to observe the histopathological changes following TXG treatment. The results demonstrated that TXG alleviated HFpEF by reducing the expressions of genes associated with myocardial hypertrophy, fibrosis and apoptosis. Furthermore, TXG improved cardiomyocyte apoptosis by inhibiting the expression of apoptosis-related proteins. Mechanistic investigations revealed that TXG could activate the inositol-requiring enzyme 1α (IRE1α)/X-box-binding protein 1 (Xbp1s) signalling pathway, but the knockdown of IRE1α using the IRE1α inhibitor STF083010 or siRNA-IRE1α impaired the ability of TXG to ameliorate cardiac remodelling in HFpEF models. In conclusion, TXG alleviates myocardial hypertrophy, fibrosis and apoptosis through the activation of the IRE1α/Xbp1s signalling pathway, suggesting its potential beneficial effects on HFpEF patients.

Xanthone Inhibitors of Unfolded Protein Response Isolated from Calophyllum caledonicum.

The unfolded protein response (UPR) is a key component of fungal virulence. The prenylated xanthone γ-mangostin isolated from Garcinia mangostana (Clusiaceae) fruit pericarp, has recently been described to inhibit this fungal adaptative pathway. Considering that Calophyllum caledonicum (Calophyllaceae) is known for its high prenylated xanthone content, its stem bark extract was fractionated using a bioassay-guided procedure based on the cell-based anti-UPR assay. Four previously undescribed xanthone derivatives were isolated, caledonixanthones N-Q (3, 4, 8, and 12), among which compounds 3 and 8 showed promising anti-UPR activities with IC50 values of 11.7 ± 0.9 and 7.9 ± 0.3 µM, respectively.

Dicerandrol C Suppresses Proliferation and Induces Apoptosis of HepG2 and Hela Cancer Cells by Inhibiting Wnt/ß-Catenin Signaling Pathway.

Overwhelming evidence points to an aberrant Wnt/ß-catenin signaling as a critical factor in hepatocellular carcinoma (HCC) and cervical cancer (CC) pathogenesis. Dicerandrol C (DD-9), a dimeric tetrahydroxanthenone isolated from the endophytic fungus Phomopsis asparagi DHS-48 obtained from mangrove plant Rhizophora mangle via chemical epigenetic manipulation of the culture, has demonstrated effective anti-tumor properties, with an obscure action mechanism. The objective of the current study was to explore the efficacy of DD-9 on HepG2 and HeLa cancer cells and its functional mechanism amid the Wnt/ß catenin signaling cascade. Isolation of DD-9 was carried out using various column chromatographic methods, and its structure was elucidated with 1D NMR. The cytotoxicity of DD-9 on HepG2 and HeLa cells was observed with respect to the proliferation, clonality, migration, invasion, apoptosis, cell cycle, and Wnt/ß-catenin signaling cascade. We found that DD-9 treatment significantly reduced tumor cell proliferation in dose- and time-dependent manners in HepG2 and HeLa cells. The subsequent experiments in vitro implied that DD-63 could significantly suppress the tumor clonality, metastases, and induced apoptosis, and that it arrested the cell cycle at the G0/G1 phase of HepG2 and HeLa cells. Dual luciferase assay, Western blot, and immunofluorescence assay showed that DD-9 could dose-dependently attenuate the Wnt/ß-catenin signaling by inhibiting ß-catenin transcriptional activity and abrogating ß-catenin translocated to the nucleus; down-regulating the transcription level of ß-catenin-stimulated Wnt target gene and the expression of related proteins including p-GSK3-ß, ß-catenin, LEF1, Axin1, c-Myc, and CyclinD1; and up-regulating GSK3-ß expression, which indicates that DD-9 stabilized the ß-catenin degradation complex, thereby inducing ß-catenin degradation and inactivation of the Wnt/ß-catenin pathway. The possible interaction between DD-9 and ß-catenin and GSK3-ß protein was further confirmed by molecular docking studies. Collectively, DD-9 may suppress proliferation and induce apoptosis of liver and cervical cancer cells, possibly at least in part via GSK3-ß-mediated crosstalk with the Wnt/ß-catenin signaling axis, providing insights into the mechanism for the potency of DD-9 on hepatocellular and cervical cancer.

Mangiferin alleviated poststroke cognitive impairment by modulating lipid metabolism in cerebral ischemia/reperfusion rats.

INTRODUCTION: Mangiferin is a Chinese herbal extract with multiple biological activities. Mangiferin can penetrate the blood‒brain barrier and has potential in the treatment of nervous system diseases. These findings suggest that mangiferin protects the neurological function in ischemic stroke rats by targeting multiple signaling pathways. However, little is known about the effect and mechanism of mangiferin in alleviating poststroke cognitive impairment. METHODS: Cerebral ischemia/reperfusion (I/R) rats were generated via middle cerebral artery occlusion. Laser speckle imaging was used to monitor the cerebral blood flow. The I/R rats were intraperitoneally (i.p.) injected with 40 mg/kg mangiferin for 7 consecutive days. Neurological scoring, and TTC staining were performed to evaluate neurological function. Behavioral experiments, including the open field test, elevated plus maze, sucrose preference test, and novel object recognition test, were performed to evaluate cognitive function. Metabolomic data from brain tissue with multivariate statistics were analyzed by gas chromatography‒mass spectrometry and liquid chromatography‒mass spectrometry. RESULTS: Mangiferin markedly decreased neurological scores, and reduced infarct areas. Mangiferin significantly attenuated anxiety-like and depression-like behaviors and enhanced learning and memory in I/R rats. According to the metabolomics results, 13 metabolites were identified to be potentially regulated by mangiferin, and the differentially abundant metabolites were mainly involved in lipid metabolism. CONCLUSIONS: Mangiferin protected neurological function and relieved poststroke cognitive impairment by improving lipid metabolism abnormalities in I/R rats.

Ultra-pH-sensitive nanoparticle of gambogenic acid for tumor targeting therapy via anti-vascular strategy plus immunotherapy.

Although the combination of anti-vascular strategy plus immunotherapy has emerged as the optimal first-line treatment of hepatocellular carcinoma, lack of tumor targeting leads to low antitumor efficacy and serious side effect. Here, we report an ultra-pH-sensitive nanoparticle of gambogenic acid (GNA) encapsulated by poly(ethylene glycol)-poly(2-azepane ethyl methacrylate) (PEG-PAEMA) for tumor-targeting combined therapy of anti-vascular strategy plus immunotherapy. PEG-PAEMA-GNA nanoparticle was quite stable at pH 7.4 for 30 d. In contrast, it exerted size shrinkage, charge reversal and the release of GNA at pH 6.7 within 24 h. Moreover, PEG-PAEMA-GNA significantly enhanced the anti-vascular activity, membrane-disruptive capability and pro-apoptosis when pH changed from 7.4 to 6.7. Western blot analysis exhibits that PEG-PAEMA and its GNA nanoparticle facilitated the phosphorylation of STING protein. In vivo assays show that PEG-PAEMA-GNA not only displayed much higher tumor inhibition of 92 % than 37 % of free GNA, but also inhibited tumor vasculature, promoted the maturation of dendritic cells and recruited more cytotoxic t-lymphocytes for sufficient anti-vascular therapy and immunotherapy. All these results demonstrate that PEG-PAEMA-GNA displayed tumor-targeting combined treatment of anti-vascular therapy and immunotherapy. This study offers a simple and novel method for the combination of anti-vascular therapy and immunotherapy with high selectivity towards tumor.

Computational and experimental approaches manifest the leishmanicidal potential of α-mangostin resourced from Garcinia cowa.

Owing to the persistent number of parasitic deaths, Visceral leishmaniasis continues to haunt several economically weaker sections of India. The disease causes over 30,000 deaths and threatens millions annually on a global scale. The standard pentavalent antimonials, on the other hand, are associated with health adversities and disease relapse. The current study is focused on the search for the most potential natural bioactive phytocompound from the bark extract of the Northeastern Indian plant, Garcinia cowa, that shows potent anti-leishmanial properties. The High Resonance Liquid Chromatography followed by Mass Spectrometry (HR-LCMS) study followed by an in silico molecular docking using computational tools revealed that α-mangostin might potentially possess antiparasitic activity. To validate the anti-leishmanial efficacy of the compound, a cell viability assay was performed, which demonstrated the parasite-specific inhibitory activity of α-mangostin; with IC50 values ranging from 4.95 - 7.37 µM against the different forms of Leishmania donovani parasite. The flow cytometric analysis of the phytocompound treated parasites indicated an oxidative and nitrosative stress-mediated apoptotic cell death in the parasites, by the suggestive surge in nuclear fragmentation and mitochondrial dysfunction. Simultaneously, a cytokine profiling study suggested approximate two-to-three-fold upregulated levels of pro-inflammatory cytokines post-compound treatment, which is predicted to actively contribute to parasite-killing. α-mangostin was also found to reduce the chances of parasite survival by inhibiting arginase enzyme activity, which in favorable conditions facilitates its sustenance. This study thereby substantiates that α-mangostin significantly possesses anti-leishmanial potentiality that can be developed into a cure for this infectious disease.

GSH-Responsive Liposomes with Heat Shock Protein Regulatory Ability for Efficient Photodynamic/Photothermal Combined Therapy of Tumors.

Phototherapy, represented by photodynamic therapy (PDT) and photothermal therapy (PTT), has great potential in tumor treatment. However, the presence of antioxidant glutathione (GSH) and the heat shock proteins (HSPs) expression caused by high temperature can weaken the effects of PDT and PTT. Here, a multifunctional nanocomplex BT&GA@CL is constructed to realize enhanced synergistic PDT/PTT. Cinnamaldehyde liposomes (CLs) formed by cinnamaldehyde dimer self-assembly were loaded with in gambogic acid (GA) and an aggregation-induced emission molecule BT to obtain BT&GA@CL. As a drug carrier, CL can consume glutathione (GSH) and release drugs responsively. The released BT aggregates can simultaneously act as both a photothermal agent and photosensitizer to achieve PDT and PTT under 660 nm laser irradiation. Specifically, GA as an HSP90 inhibitor can attenuate PTT-induced HSP90 protein expression, thereby weakening the tolerance of tumor cells to high temperatures and enhancing PTT. Such a multifunctional nanocomplex simultaneously modulates the content of GSH and HSP90 in tumor cells, thus enhancing both PDT and PTT, ultimately achieving the goal of efficient combined tumor suppression.

Natural gambogic acid-tuned self-assembly of nanodrugs towards synergistic chemophototherapy against breast cancer.

Gambogic acid (GA) as a naturally derived chemotherapeutic agent is of increasing interest for antitumor therapy. However, current research mainly focuses on improving the pharmacological properties to overcome the shortcomings in clinical applications or as a synergistic anticancer agent in combination with chemotherapy and chemophototherapy. Yet, the material properties of GA (e.g., self-assembly) are often neglected. Herein, we validated the self-assembly function of GA and its huge potential as a single-component active carrier for synergistic delivery using pyropheophorbide-a (PPa) as a drug model. The results showed that self-assembled GA drives the formation of nano-GA/PPa mainly through noncovalent interactions such as π-π stacking, hydrophobic interactions, and hydrogen bonding. Additionally, although no significant differences in cytotoxicity were found between the individual in vitro chemotherapy and combined chemophototherapy, the as-prepared nano-GA/PPa exhibits remarkably improved water solubility and multiple favorable therapeutic features, leading to a prominent in vivo photochemotherapy efficiency of 89.3% inhibition rate with reduced hepatotoxicity of GA. This work highlights the potential of self-assembled GA as a drug delivery carrier for synergistic biomedical applications.

Nucleobase-Coupled Xanthones with Anti-ROS Effects from Marine-Derived Fungus Aspergillus sydowii.

A MS/MS-based molecular networking approach compared to the Global Natural Product Social Molecular Networking library, in association with genomic annotation of natural product biosynthetic gene clusters within a marine-derived fungus, Aspergillus sydowii, identified a suite of xanthone metabolites. Chromatographic techniques applied to the cultured fungus led to the isolation of 11 xanthone-based alkaloids, dubbed sydoxanthones F-M. The structures of these alkaloids were elucidated using extensive spectroscopic data, including electronic circular dichroism and single-crystal X-ray diffraction data for configurational assignments. Among these analogues, sydoxanthones F-K exhibit structure features typical of nucleobase-coupled xanthones, with sydoxanthone H being an N-bonded xanthone dimer. Notably, (±)sydoxanthones F (1a/1b), (±)sydoxanthones H (3b/3a), and (±)sydoxanthones J (5b/5a) are enantiomeric pairs, while sydoxanthones G (2), I (4), and K (6) are stereoisomers of 1, 3, and 5, respectively. Furthermore, (+)sydoxanthone H (3a) demonstrated significant rescue of cell viability in H2O2-injuried SH-SY5Y cells by inhibiting reactive oxygen species production, suggesting its potential for neuroprotection.