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2.
Sci Total Environ ; 859(Pt 1): 160135, 2023 Feb 10.
Article En | MEDLINE | ID: mdl-36375547

Rapid global industrialization has resulted in widespread cadmium contamination in agricultural soils and products. A considerable proportion of rice consumers are exposed to Cd levels above the provisional safe intake limit, raising widespread environmental concerns on risk management. Therefore, a generalized approach is urgently needed to enable correct evaluation and early warning of cadmium contaminants in rice products. Combining big data and computer science together, this study developed a system named "SMART Cd Early Warning", which integrated 4 modules including genotype-to-phenotype (G2P) modelling, high-throughput sequencing, G2P prediction and rice Cd contamination risk assessment, for rice cadmium accumulation early warning. This system can rapidly assess the risk of rice cadmium accumulation by genotyping leaves at seeding stage. The parameters including statistical methods, population size, training population-testing population ratio, SNP density were assessed to ensure G2P model exhibited superior performance in terms of prediction precision (up to 0.76 ± 0.003) and computing efficiency (within 2 h). In field trials of cadmium-contaminated farmlands in Wenling and Fuyang city, Zhejiang Province, "SMART Cd Early Warning" exhibited superior capability for identification risk rice varieties, suggesting a potential of "SMART Cd Early-Warning system" in OsGCd risk assessment and early warning in the age of smart.


Oryza , Soil Pollutants , Cadmium/analysis , Soil Pollutants/analysis , Soil , Risk Assessment
3.
Cell Death Discov ; 8(1): 497, 2022 Dec 24.
Article En | MEDLINE | ID: mdl-36566230

N6-methylation of adenosine (m6A) is one of the most frequent chemical modifications in eukaryotic RNAs and plays a vital role in tumorigenesis and progression. Recently, emerging studies have shown that m6A modification by ALKBH5 was associated with immunotherapy response in various types of cancer. However, whether m6A demethylases ALKBH5 participate in regulating the tumor immune microenvironment and the efficacy of immunotherapy in glioblastoma remain unknown. Here, we found that deletion of ALKBH5 significantly inhibited the growth of glioma allografts, rescued the antitumoral immune response, and increased cytotoxic lymphocyte infiltration and proinflammatory cytokines in CSF while significantly suppressing PD-L1 protein expression. m6A-methylated RNA immunoprecipitation sequencing and RNA sequencing identify ZDDHC3 as the direct target of ALKBH5. Mechanically, ALKBH5 deficiency impairs the YTHDF2-mediated stability of ZDHHC3 mRNA, thereby suppressing PD-L1 expression by accelerating PD-L1 degradation in glioma. In addition, genetic deletion or pharmacological inhibition of ALKBH5 with IOX1 enhances the therapeutic efficacy of anti-PD-1 treatment in preclinical mice models. These data suggest that the combination of anti-PD-1 therapy and ALKBH5 inhibition may be a promising treatment strategy in glioma.

4.
Cell Death Dis ; 13(12): 1040, 2022 12 14.
Article En | MEDLINE | ID: mdl-36517470

Ferroptosis is a recently-defined tumor suppression mechanism, but the sensitivity of many tumorigenic cells to ferroptosis is limited by their deficient expression of acyl-CoA synthetase long-chain family member 4 (ACSL4). Here, we report the discovery of a photosensitizer, namely TPCI, which can evoke ACSL4-independent ferroptosis of cancer cells in photodynamic therapy. Through co-localization with 12-lipoxygenase (ALOX12) in multiple subcellular organelles, TPCI activates ALOX12 to generate lipid reactive oxygen species in large quantity and trigger cell ferroptosis. Intriguingly, confining TPCI exclusively in lysosomes switches the cell death from ferroptosis to apoptosis. More strikingly, the ferroptosis mediated by TPCI-induced ALOX12 activation does not require the participation of ACSL4. Therefore, our study identifies TPCI as the first ALOX12 activator to induce ferroptosis independent of ACSL4, which renders a viable therapeutic approach on the basis of distinct ferroptosis of cancer cells, regardless their ACSL4 expressions.


Ferroptosis , Photosensitizing Agents/pharmacology , Coenzyme A Ligases/metabolism , Apoptosis , Organelles/metabolism
5.
Article En | MEDLINE | ID: mdl-36301911

Two-dimensional (2D) nanomaterials hold great potential for cancer theranostic applications, yet their clinical translation faces great challenges of high toxicity and limited therapeutic/diagnostic modality. Here, we have created a kind of symbiotic 2D carbon-2D clay nanohybrids, which are composed of a novel 2D carbon nanomaterial (carbon nanochips, or CNC), prepared by carbonizing a conjugated polymer polydiiodobutadiyne, and a 2D layered aluminosilicate clay mineral montmorillonite (MMT). Intriguingly, with the formation of the nanohybrids, MMT can help the dispersion of CNC, while CNC can significantly reduce the hemolysis and toxicity of MMT. The symbiotic combination of CNC and MMT also leads to a synergistic anti-cancer theranostic effect. CNC has a strong absorption and high photothermal conversion efficiency in the second near-infrared region (NIR-II, 1000-1700 nm), while MMT contains Fe3+ that can facilitate the generation of reactive oxygen species from highly expressed H2O2 in tumor microenvironment. The nanohybrids not only enable a synergy of photothermal therapy and chemodynamic therapy to suppress the extremely rapid growth of RM1 tumors in mice but also allow for dual photoacoustic and magnetic imaging to guide the drug delivery and NIR-II irradiation execution, hence establishing a highly efficient and biosafe "all-in-one" theranostic platform for precision nanomedicine.

6.
Chemosphere ; 309(Pt 1): 136612, 2022 Dec.
Article En | MEDLINE | ID: mdl-36179923

Mercury (Hg) is a toxic and nonessential element for organisms, and its contamination in the environment is a global concern. Previous research has shown that Hg stress may cause severe damage to rice roots; however, the transcriptomic changes in roots and physio-biochemical responses in leaves to different levels of Hg stress are not fully understood. In the present study, rice seedlings were exposed to 20, 80, and 160 µM HgCl2 for three days in hydroponic experiments. The results showed that the majority of Hg was accumulated in rice roots after Hg exposure, and the 80- and 160-µM Hg stresses significantly increased the root-to-shoot translocation factors relative to 20-µM Hg stress, resulting in elevated Hg concentrations in rice shoots. Only the 160-µM Hg stress significantly inhibited root growth compared with the control, while photosynthesis capacity in leaves was significantly reduced under Hg stress. RNA transcriptome sequencing analyses of the roots showed that common responsive differentially expressed genes were strongly associated with glutathione metabolism, amino acid biosynthesis, and secondary metabolite metabolism, which may play significant roles in Hg accumulation by rice plants. Nine crucial genes identified by protein-protein interaction network analysis may be used as candidate target genes for further investigation of the detoxification mechanism, encoding proteins involved in jasmonic acid synthesis, sugar metabolism, allene oxide synthase, glutathione peroxidase, dismutase, and catalase. Furthermore, physio-biochemical analyses of the leaves indicated that higher production of reactive oxygen species was induced by Hg stress, while glutathione and antioxidant enzymes may play crucial roles in Hg detoxification. Our findings provide transcriptomic and physio-biochemical features of rice roots and shoots, which advance our understanding of the responsive and detoxification mechanisms in rice under different levels of Hg stress.


Mercury , Oryza , Oryza/metabolism , Catalase/metabolism , Mercury/analysis , Transcriptome , Antioxidants/metabolism , Reactive Oxygen Species/metabolism , Glutathione Peroxidase/metabolism , Plant Roots/metabolism , Seedlings/metabolism , Glutathione/metabolism , Amino Acids/metabolism , Sugars/metabolism , RNA/metabolism
7.
Acta Pharm Sin B ; 12(7): 3063-3072, 2022 Jul.
Article En | MEDLINE | ID: mdl-35865093

Adipose tissue is a promising target for treating obesity and metabolic diseases. However, pharmacological agents usually fail to effectively engage adipocytes due to their extraordinarily large size and insufficient vascularization, especially in obese subjects. We have previously shown that during cold exposure, connexin43 (Cx43) gap junctions are induced and activated to connect neighboring adipocytes to share limited sympathetic neuronal input amongst multiple cells. We reason the same mechanism may be leveraged to improve the efficacy of various pharmacological agents that target adipose tissue. Using an adipose tissue-specific Cx43 overexpression mouse model, we demonstrate effectiveness in connecting adipocytes to augment metabolic efficacy of the ß 3-adrenergic receptor agonist Mirabegron and FGF21. Additionally, combing those molecules with the Cx43 gap junction channel activator danegaptide shows a similar enhanced efficacy. In light of these findings, we propose a model in which connecting adipocytes via Cx43 gap junction channels primes adipose tissue to pharmacological agents designed to engage it. Thus, Cx43 gap junction activators hold great potential for combination with additional agents targeting adipose tissue.

8.
ACS Appl Mater Interfaces ; 14(27): 30533-30545, 2022 Jul 13.
Article En | MEDLINE | ID: mdl-35771755

With the emergence and global spread of bacterial resistance, pathogenic bacterial infections have become a serious threat to human health. Thus, therapeutic strategies with highly antibacterial efficacy and a low tendency to induce drug resistance are strongly desired to combat bacterial infections. Here, an ultra-efficient photodynamic/chemodynamic theranostics platform is developed by intercalating an aggregation-induced emission (AIE) photosensitizer, TPCI, into the nanolayers of iron-bearing montmorillonite (MMT). The formed TPCI/MMT composite can not only perform efficient photodynamic therapy (PDT) through a burst generation of singlet oxygen (1O2) upon white light illumination but also continuously implement chemodynamic therapy (CDT) by converting endogenous hydrogen peroxide into highly toxic hydroxyl radicals (•OH) due to iron release. In addition, the fluorescence of TPCI/MMT can be activated due to the AIE feature of TPCI, which helps guide the location of the antimicrobials. The combination of such powerful bombs (PDT) and unremitting ambushes (CDT) in TPCI/MMT can synergistically and effectively eliminate bacteria and promote faster wound healing in vivo with good biocompatibility and low side effects. The smart and simple design of TPCI/MMT provides a representative paradigm for achieving efficient antimicrobials to combat the coming resistance crisis.


Anti-Infective Agents , Photochemotherapy , Anti-Infective Agents/therapeutic use , Bacteria , Humans , Iron , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Precision Medicine , Theranostic Nanomedicine , Wound Healing
9.
Front Immunol ; 13: 873382, 2022.
Article En | MEDLINE | ID: mdl-35720361

Adiponectin (APN), a fat-derived plasma hormone, is a classic anti-inflammatory agent. Multiple studies have demonstrated the beneficial role of APN in acute brain injury, but the effect of APN in germinal matrix hemorrhage (GMH) is unclear, and the underlying molecular mechanisms remain largely undefined. In the current study, we used a GMH rat model with rh-APN treatment, and we observed that APN demonstrated a protective effect on neurological function and an inhibitory effect on neuroinflammation after GMH. To further explore the underlying mechanisms of these effects, we found that the expression of Adiponectin receptor 1 (AdipoR1) primarily colocalized with microglia and neurons in the brain. Moreover, AdiopR1, but not AdipoR2, was largely increased in GMH rats. Meanwhile, further investigation showed that APN treatment promoted AdipoR1/APPL1-mediated AMPK phosphorylation, further increased peroxisome proliferator-activated receptor gamma (PPARγ) expression, and induced microglial M2 polarization to reduce the neuroinflammation and enhance hematoma resolution in GMH rats. Importantly, either knockdown of AdipoR1, APPL1, or LKB1, or specific inhibition of AMPK/PPARγ signaling in microglia abrogated the protective effect of APN after GMH in rats. In all, we propose that APN works as a potential therapeutic agent to ameliorate the inflammatory response following GMH by enhancing the M2 polarization of microglia via AdipoR1/APPL1/AMPK/PPARγ signaling pathway, ultimately attenuating inflammatory brain injury induced by hemorrhage.


Brain Injuries , Microglia , AMP-Activated Protein Kinases/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Adiponectin/metabolism , Adiponectin/pharmacology , Animals , Animals, Newborn , Brain Injuries/drug therapy , Brain Injuries/etiology , Brain Injuries/metabolism , Carrier Proteins/metabolism , Cerebral Hemorrhage/drug therapy , Cerebral Hemorrhage/metabolism , Microglia/metabolism , Nerve Tissue Proteins/metabolism , PPAR gamma/metabolism , Rats , Signal Transduction
10.
Cancer Sci ; 113(8): 2681-2692, 2022 Aug.
Article En | MEDLINE | ID: mdl-35637600

The discovery of long noncoding RNAs (lncRNAs) has improved the understanding of development and progression in various cancer subtypes. However, the role of lncRNAs in temozolomide (TMZ) resistance in glioblastoma multiforme (GBM) remains largely undefined. In this present study, the differential expression of lncRNAs was identified between U87 and U87 TMZ-resistant (TR) cells. lncRNA XLOC013218 (XLOC) was drastically upregulated in TR cells and was associated with poor prognosis in glioma. Overexpression of XLOC markedly increased TMZ resistance, promoted proliferation, and inhibited apoptosis in vitro and in vivo. In addition, RNA-seq analysis and gain-of-function or loss-of-function studies revealed that PIK3R2 was the potential target of XLOC. Mechanistically, XLOC recruited specificity protein 1 (Sp1) transcription factor and promoted the binding of Sp1 to the promoters of PIK3R2, which elevated the expression of PIK3R2 in both mRNA and protein levels. Finally, PIK3R2-mediated activation of the PI3K/AKT signaling pathway promoted TMZ resistance and cell proliferation, but inhibited cell apoptosis. In conclusion, these data highlight the vital role of the XLOC/Sp1/PIK3R2/PI3K/AKT axis in GBM TMZ resistance.


Brain Neoplasms , Drug Resistance, Neoplasm , Glioblastoma , Glioma , Phosphatidylinositol 3-Kinases , RNA, Long Noncoding , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Cell Line, Tumor , Cell Proliferation/genetics , Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Neoplastic , Glioblastoma/drug therapy , Glioblastoma/genetics , Glioma/drug therapy , Glioma/genetics , Humans , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , RNA, Long Noncoding/genetics , Temozolomide/pharmacology , Transcription Factors/genetics
11.
New Phytol ; 233(6): 2488-2502, 2022 03.
Article En | MEDLINE | ID: mdl-35015902

Pteris vittata is an arsenic (As) hyperaccumulator that can accumulate several thousand mg As kg-1 DW in aboveground biomass. A key factor for its hyperaccumulation ability is its highly efficient As long-distance translocation system. However, the underlying molecular mechanisms remain unknown. We isolated PvAsE1 through the full-length cDNA over-expression library of P. vittata and characterized it through a yeast system, RNAi gametophytes and sporophytes, subcellular-location and in situ hybridization. Phylogenomic analysis was conducted to estimate the appearance time of PvAsE1. PvAsE1 was a plasma membrane-oriented arsenite (AsIII) effluxer. The silencing of PvAsE1 reduced AsIII long-distance translocation in P. vittata sporophytes. PvAsE1 was structurally similar to solute carrier (SLC)13 proteins. Its transcripts could be observed in parenchyma cells surrounding the xylem of roots. The appearance time was estimated at c. 52.7 Ma. PvAsE1 was a previously uncharacterized SLC13-like AsIII effluxer, which may contribute to AsIII long-distance translocation via xylem loading. PvAsE1 appeared late in fern evolution and might be an adaptive subject to the selection pressure at the Cretaceaou-Paleogene boundary. The identification of PvAsE1 provides clues for revealing the special As hyperaccumulation characteristics of P. vittata.


Arsenic , Arsenites , Ferns , Pteris , Soil Pollutants , Arsenic/metabolism , Arsenites/metabolism , Biodegradation, Environmental , Ferns/metabolism , Plant Roots/metabolism , Pteris/genetics , Soil Pollutants/analysis , Soil Pollutants/metabolism
12.
Mol Metab ; 54: 101352, 2021 12.
Article En | MEDLINE | ID: mdl-34626854

OBJECTIVE: Long-acting glucagon-like peptide-1 receptor agonists (GLP-1RAs), like liraglutide and semaglutide, are viable treatments for diabetes and obesity. Liraglutide directly activates hypothalamic proopiomelanocortin (POMC) neurons while indirectly inhibiting Neuropeptide Y/Agouti-related peptide (NPY/AgRP) neurons ex vivo. While temporal control of GLP-1R agonist concentration as well as accessibility to tissues/cells can be achieved with relative ease ex vivo, in vivo this is dependent upon the pharmacokinetics of these agonists and relative penetration into structures of interest. Thus, whether liraglutide or semaglutide modifies the activity of POMC and NPY/AgRP neurons in vivo as well as mechanisms required for any changes in cellular activity remains undefined. METHODS: In order to resolve this issue, we utilized neuron-specific transgenic mouse models to examine changes in the activity of POMC and NPY/AgRP neurons after injection of either liraglutide or semaglutide (intraperitoneal - I.P. and subcutaneous - S·C.). POMC and NPY/AgRP neurons were targeted for patch-clamp electrophysiology as well as in vivo fiber photometry. RESULTS: We found that liraglutide and semaglutide directly activate and increase excitatory tone to POMC neurons in a time-dependent manner. This increased activity of POMC neurons required GLP-1Rs in POMC neurons as well as a downstream mixed cation channel comprised of TRPC5 subunits. We also observed an indirect upregulation of excitatory input to POMC neurons originating from glutamatergic cells that also required TRPC5 subunits. Conversely, GLP-1Ra's decreased excitatory input to and indirectly inhibited NPY/AgRP neurons through activation of K-ATP and TRPC5 channels in GABAergic neurons. Notably, the temporal activation of POMC and inhibition of NPY/AgRP neuronal activity after liraglutide or semaglutide was injected [either intraperitoneal (I.P.) or subcutaneous (S·C.)] was dependent upon the nutritional state of the animals (fed vs food-deprived). CONCLUSIONS: Our results support a mechanism of liraglutide and semaglutide in vivo to activate POMC while inhibiting NPY/AgRP neurons, which depends upon metabolic state and mirrors the pharmacokinetic profile of these compounds in vivo.


Agouti-Related Protein/metabolism , Glucagon-Like Peptides/pharmacology , Liraglutide/pharmacology , Neurons/drug effects , Neuropeptide Y/metabolism , Pro-Opiomelanocortin/metabolism , Animals , Glucagon-Like Peptide-1 Receptor/agonists , Glucagon-Like Peptides/administration & dosage , Injections, Intraperitoneal , Injections, Subcutaneous , Liraglutide/administration & dosage , Male , Mice , Mice, Knockout , Mice, Transgenic , Neurons/metabolism , Time Factors
13.
Adv Healthc Mater ; 10(24): e2101056, 2021 12.
Article En | MEDLINE | ID: mdl-34569175

Two-photon photodynamic therapy (2P-PDT) that employs photosensitizers (PSs) with 2P absorption is particularly intriguing in cancer treatment, in that 2P excitation enables precise spatial localization and deep tissue penetration. Here, a donor-π-acceptor PS (named TPBPy) with near infrared (NIR) aggregation-induced emission (AIE) is designed and synthesized for imaging-guided 2P-PDT. The maximal photoluminescence (PL) peak of TPBPy is as high as 720 nm when it is encapsulated in liposomes. Upon 2P irradiation by a laser in NIR-II window (λ = 1000 nm), TPBPy exhibits strong NIR-I PL in a multicellular tumor spheroids (MCTSs) model, showing an imaging depth of 210 µm that is significantly higher than upon one-photon irradiation. Moreover, TPBPy localizes specifically on mitochondrion, an important organelle in cell oxidative metabolism and apoptosis. When exposed to the NIR-II irradiation, TPBPy can efficiently generate singlet oxygen (1 O2 ) and trigger cell death. The efficacy of TPBPy-mediated 2P-PDT has also been validated using 4T1 tumor mouse model, the growth of which is significantly suppressed upon NIR-II laser irradiation. TPBPy herein serves as an excellent candidate to suppress deep tumor tissues through NIR-II 2P-PDT, and also renders a new paradigm to construct mitochondrion-anchored AIE luminogens for future cancer theranostic applications.


Photochemotherapy , Photosensitizing Agents , Animals , Mice , Mitochondria , Photons , Photosensitizing Agents/pharmacology , Singlet Oxygen
14.
Article En | MEDLINE | ID: mdl-34567206

Astragalus membranaceus has complex components as a natural drug and has multilevel, multitarget, and multichannel effects on dilated cardiomyopathy (DCM). However, the immune mechanism, gene module, and molecular subtype of astragalus membranaceus in the treatment of DCM are still not revealed. Microarray information of GSE84796 was downloaded from the GEO database, including RNA sequencing data of seven normal cardiac tissues and ten DCM cardiac tissues. A total of 4029 DCM differentially expressed genes were obtained, including 1855 upregulated genes and 2174 downregulated genes. GO/KEGG/GSEA analysis suggested that the activation of T cells and B cells was the primary cause of DCM. WGCNA was used to obtain blue module genes. The blue module genes are primarily ADCY7, BANK1, CD1E, CD19, CD38, CD300LF, CLEC4E, FLT3, GPR18, HCAR3, IRF4, LAMP3, MRC1, SYK, and TLR8, which successfully divided DCM into three molecular subtypes. Based on the CIBERSORT algorithm, the immune infiltration profile of DCM was analyzed. Many immune cell subtypes, including the abovementioned immune cells, showed different levels of increased infiltration in the myocardial tissue of DCM. However, this infiltration pattern was not obviously correlated with clinical characteristics, such as age, EF, and sex. Based on network pharmacology and ClueGO, 20 active components of Astragalus membranaceus and 40 components of DMCTGS were obtained from TCMSP. Through analysis of the immune regulatory network, we found that Astragalus membranaceus effectively regulates the activation of immune cells, such as B cells and T cells, cytokine secretion, and other processes and can intervene in DCM at multiple components, targets, and levels. The above mechanisms were verified by molecular docking results, which confirmed that AKT1, VEGFA, MMP9, and RELA are promising potential targets of DCM.

15.
Front Oncol ; 11: 698835, 2021.
Article En | MEDLINE | ID: mdl-34490096

BACKGROUND: Neuronal activity regulated by synaptic communication exerts an important role in tumorigenesis and progression in brain tumors. Genes for soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) annotated with the function 'vesicle' about synaptic connectivity were identified, and synaptosomal-associated protein 25 (SNAP25), one of those proteins, was found to have discrepant expression levels in neuropathies. However, the specific mechanism and prognostic value of SNAP25 during glioma progression remain unclear. METHODS: Using RNA sequencing data from The Cancer Genome Atlas (TCGA) database, the differential synaptosis-related genes between low grade glioma (LGG) and glioblastoma (GBM) were identified as highly correlated. Cox proportional hazards regression analysis and survival analysis were used to differentiate the outcome of low- and high-risk patients, and the Chinese Glioma Genome Atlas (CGGA) cohort was used for validation of the data set. RT-qPCR, western blot, and immunohistochemistry assays were performed to examine the expression level of SNAP25 in glioma cells and samples. Functional assays were performed to identify the effects of SNAP25 knockdown and overexpression on cell viability, migration, and invasion. Liquid chromatography-high resolution mass spectrometry (LC-MS)-based metabolomics approach was presented for identifying crucial metabolic disturbances in glioma cells. In situ mouse xenograft model was used to investigate the role of SNAP25 in vivo. Then, an immunofluorescence assay of the xenograft tissue was applied to evaluate the expression of the neuronal dendron formation marker-Microtubule Associated Protein 2 (MAP2). RESULTS: SNAP25 was decreased in level of expression in glioma tissues and cell lines, and low-level SNAP25 indicated an unfavorable prognosis of glioma patients. SNAP25 inhibited cell proliferation, migration, invasion and fostered glutamine metabolism of glioma cells, exerting a tumor suppressor role. Overexpressed SNAP25 exerted a lower expression level of MAP2, indicating poor neuronal plasticity and connectivity. SNAP25 could regulate glutaminase (GLS)-mediated glutaminolysis, and GLS knockdown could rescue the anti-tumor effect of SNAP25 in glioma cells. Moreover, upregulated SNAP25 also decreased tumor volume and prolonged the overall survival (OS) of the xenograft mouse. CONCLUSION: SNAP25, a tumor suppressor inhibited carcinogenesis of glioma via limiting glutamate metabolism by regulating GLS expression, as well as inhibiting dendritic formation, which could be considered as a novel molecular therapeutic target for glioma.

16.
JCI Insight ; 6(18)2021 09 22.
Article En | MEDLINE | ID: mdl-34549728

ER stress and activation of the unfolded protein response in the periphery as well as the central nervous system have been linked to various metabolic abnormalities. Chemically lowering protein kinase R-like ER kinase (PERK) activity within the hypothalamus leads to decreased food intake and body weight. However, the cell populations required in this response remain undefined. In the current study, we investigated the effects of proopiomelanocortin-specific (POMC-specific) PERK deficiency on energy balance and glucose metabolism. Male mice deficient for PERK in POMC neurons exhibited improvements in energy balance on a high-fat diet, showing decreased food intake and body weight, independent of changes in glucose and insulin tolerances. The plant-based inhibitor of PERK, celastrol, increases leptin sensitivity, resulting in decreased food intake and body weight in a murine model of diet-induced obesity (DIO). Our data extend these observations by demonstrating that celastrol-induced improvements in leptin sensitivity and energy balance were attenuated in mice with PERK deficiency in POMC neurons. Altogether, these data suggest that POMC-specific PERK deficiency in male mice confers protection against DIO, possibly providing a new therapeutic target for the treatment of diabetes and metabolic syndrome.


Energy Metabolism , Glucose/metabolism , Leptin/pharmacology , Pentacyclic Triterpenes/pharmacology , Pro-Opiomelanocortin/physiology , eIF-2 Kinase/antagonists & inhibitors , Animals , Arcuate Nucleus of Hypothalamus/cytology , Body Weight/drug effects , Diet, High-Fat/adverse effects , Eating/drug effects , Endoplasmic Reticulum Stress , Insulin Resistance , Male , Mice , Mice, Knockout , Neurons , Obesity/etiology , Obesity/prevention & control , Pro-Opiomelanocortin/metabolism , eIF-2 Kinase/genetics
17.
FASEB J ; 35(7): e21748, 2021 07.
Article En | MEDLINE | ID: mdl-34152016

Although adipose-derived human mesenchymal stem cell (hADSC) transplantation has recently emerged as a promising therapeutic modality for Parkinson's disease (PD), its underlying mechanism of action has not been fully elucidated. This study evaluated the therapeutic effects of stereotaxic injection of hADSCs in the striatum of the 6-OHDA-induced mouse model. Furthermore, an in vitro PD model was constructed using tissue-organized brain slices. The therapeutic effect was also evaluated using a co-culture of the hADSCs and 6-OHDA-treated brain slice. The analysis of hADSC exocrine proteins using RNA-sequencing, human protein cytokine arrays, and label-free quantitative proteomics identified key extracellular factors in the hADSC secretion environment. The degeneration and apoptosis of the dopaminergic neurons were measured in the PD samples in vivo and in vitro, and the beneficial effects were evaluated using quantitative reverse transcription-polymerase chain reaction, western blotting, Fluoro-Jade C, TUNEL assay, and immunofluorescence analysis. This study found that hADSCs protected the dopaminergic neurons in the in vivo and vitro models. We identified Pentraxin 3 (PTX3) as a key extracellular factor in the hADSC secretion environment. Moreover, we found that human recombinant PTX3 (rhPTX3) treatment could rescue the pathophysiological behavior of the PD mice in vivo, prevent dopaminergic neuronal death, and increase neuronal terminals in the ventral tegmental area + substantia nigra pars compacta and striatum in the PD brain slices in vitro. Furthermore, testing of the pro-apoptotic markers in the PD mouse brain following rhPTX3 treatment revealed that rhPTX3 can prevent apoptosis and degeneration of the dopaminergic neurons. This study discovered that PTX3, a hADSC-secreted protein, potentially protected the dopaminergic neurons against apoptosis and degeneration during PD progression and improved motor performance in PD mice, indicating the possible mechanism of action of hADSC replacement therapy for PD. Thus, our study discovered potential translational implications for the development of PTX3-based therapeutics for PD.


Adipose Tissue/metabolism , Apoptosis/physiology , C-Reactive Protein/metabolism , Dopamine/metabolism , Dopaminergic Neurons/metabolism , Mesenchymal Stem Cells/metabolism , Parkinson Disease/metabolism , Serum Amyloid P-Component/metabolism , Animals , Cell Death/physiology , Cells, Cultured , Corpus Striatum/metabolism , Disease Models, Animal , Humans , Male , Mice , Mice, Inbred C57BL
18.
Front Chem ; 9: 672917, 2021.
Article En | MEDLINE | ID: mdl-34113602

Photodynamic therapy (PDT) is an emerging effective strategy for cancer treatment. Compared with conventional cancer therapies, such as surgery, chemotherapy, and radiotherapy, PDT has shown great promise as a next-generation cancer therapeutic strategy owing to its many advantages such as non-invasiveness, negligible observed drug resistance, localized treatment, and fewer side effects. One of the key elements in photodynamic therapy is the photosensitizer (PS) which converts photons into active cytotoxic species, namely, reactive oxygen species (ROS). An ideal PS for photodynamic therapy requires the efficient generation of ROS, high stability against photo bleaching, and robust performance in different environments and concentrations. PSs with aggregation-induced emission (AIE) characteristics have drawn significant attention, in that they can overcome the aggregation- caused quenching effect that is commonly seen in the case of fluorescence dyes and provide excellent performance at high concentrations or in their condensed state. Moreover, organic nanomaterials with AIE characteristics, or AIE dots, have played an increasingly significant role in assisting PDT based on its excellent ROS generation efficiency and simultaneous imaging feature. This review summarizes the recent advances on the molecular design of AIE PSs and AIE dots-based probes, as well as their emerging applications for enhanced anticancer PDT theranostics.

19.
ACS Appl Mater Interfaces ; 13(13): 14911-14919, 2021 Apr 07.
Article En | MEDLINE | ID: mdl-33764749

Photosensitizers that can generate reactive oxygen species (ROS) upon irradiation have emerged as promising agents for photodynamic degradation of toxic amyloid aggregates that are linked to many amyloidogenic diseases. However, due to the ultrastable ß-sheet structure in amyloid aggregates and inefficient utilization of the generated ROS, it usually requires high stoichiometric concentration of the photosensitizer and/or intensive light irradiation to fully dissociate aggregates. In this work, we have developed a "bait-hook-devastate" strategy to boost the efficiency of the photodynamic degradation of amyloid aggregates. This strategy employs anionic polyacrylic acid as a bait to accumulate cationic human islet amyloid polypeptide (IAPP) aggregates and positively charged photosensitizer TPCI in a confined area through electronic interactions. Multiple characterization studies proved that the utilization rate of ROS generated by TPCI was remarkably improved via this strategy, which amplified the ability of TPCI to dissociate IAPP aggregates. Rapid and complete degradation of IAPP aggregates could be achieved by irradiating the system under very mild conditions for less than 30 min, and the IAPP-mediated cytotoxicity was also largely alleviated, providing a new paradigm to accelerate photodynamic degradation of amyloid aggregates for further practical applications.


Amyloid/metabolism , Islet Amyloid Polypeptide/metabolism , Photosensitizing Agents/pharmacology , Proteolysis/drug effects , Amyloid/pharmacology , Animals , Cell Line, Tumor , Humans , Islet Amyloid Polypeptide/ultrastructure , Protein Aggregates/drug effects , Protein Aggregates/radiation effects , Protein Aggregation, Pathological/drug therapy , Protein Aggregation, Pathological/metabolism , Proteolysis/radiation effects , Rats , Reactive Oxygen Species/metabolism
20.
Sci Adv ; 6(23): eaaz1341, 2020 06.
Article En | MEDLINE | ID: mdl-32537493

ß-Arrestin-1 and ß-arrestin-2 have emerged as important signaling molecules that modulate glucose fluxes in several peripheral tissues. The potential roles of neuronally expressed ß-arrestins in regulating glucose homeostasis remain unknown. We here report that mice lacking ß-arrestin-1 (barr1) selectively in AgRP neurons displayed impaired glucose tolerance and insulin sensitivity when consuming an obesogenic diet, while mice overexpressing barr1 selectively in AgRP neurons were protected against obesity-associated metabolic impairments. Additional physiological, biochemical, and electrophysiological data indicated that the presence of barr1 is essential for insulin-mediated hyperpolarization of AgRP neurons. As a result, barr1 expressed by AgRP neurons regulates efferent neuronal pathways that suppress hepatic glucose production and promote lipolysis in adipose tissue. Mice lacking ß-arrestin-2 (barr2) selectively in AgRP neurons showed no substantial metabolic phenotypes. Our data suggest that agents able to enhance the activity of barr1 in AgRP neurons may prove beneficial as antidiabetic drugs.

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