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1.
J Transl Med ; 22(1): 211, 2024 Feb 28.
Article in English | MEDLINE | ID: mdl-38419085

ABSTRACT

BACKGROUND: Lactylation, a novel contributor to post-translational protein modifications, exhibits dysregulation across various tumors. Nevertheless, its intricate involvement in colorectal carcinoma, particularly for non-histone lactylation and its intersection with metabolism and immune evasion, remains enigmatic. METHODS: Employing immunohistochemistry on tissue microarray with clinical information and immunofluorescence on colorectal cell lines, we investigated the presence of global lactylation and its association with development and progression in colorectal cancer as well as its functional location. Leveraging the AUCell algorithm alongside correlation analysis in single-cell RNA sequencing data, as well as cox-regression and lasso-regression analysis in TCGA dataset and confirmed in GEO dataset, we identified a 23-gene signature predicting colorectal cancer prognosis. Subsequently, we analyzed the associations between the lactylation related gene risk and clinical characteristics, mutation landscapes, biological functions, immune cell infiltration, immunotherapy responses, and drug sensitivity. Core genes were further explored for deep biological insights through bioinformatics and in vitro experiments. RESULTS: Our study innovatively reveals a significant elevation of global lactylation in colorectal cancer, particularly in malignant tumors, confirming it as an independent prognostic factor for CRC. Through a comprehensive analysis integrating tumor tissue arrays, TCGA dataset, GEO dataset, combining in silico investigations and in vitro experiments, we identified a 23-gene Lactylation-Related Gene risk model capable of predicting the prognosis of colorectal cancer patients. Noteworthy variations were observed in clinical characteristics, biological functions, immune cell infiltration, immune checkpoint expression, immunotherapy responses and drug sensitivity among distinct risk groups. CONCLUSIONS: The Lactylation-Related Gene risk model exhibits significant potential for improving the management of colorectal cancer patients and enhancing therapeutic outcomes, particularly at the intersection of metabolism and immune evasion. This finding underscores the clinical relevance of global lactylation in CRC and lays the groundwork for mechanism investigation and targeted therapeutic strategies given the high lactate concentration in CRC.


Subject(s)
Colorectal Neoplasms , Immunotherapy , Humans , Prognosis , Algorithms , Cell Line , Colorectal Neoplasms/genetics , Tumor Microenvironment
2.
Molecules ; 29(2)2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38276622

ABSTRACT

Chemical kinetic studies of the ß-scission reaction class of hydroperoxyl alkyl hydroperoxyl radicals (•P(OOH)2) from normal-alkyl cyclohexanes are carried out systematically through high-level ab initio calculations. Geometry optimizations and frequency calculations for all species involved in the reactions are performed at the B3LYP/CBSB7 level of theory. Electronic single-point energy calculations are calculated at the CBS-QB3 level of theory. Rate constants for the reactions of ß-scission, in the temperature range of 500-1500 K and the pressure range of 0.01-100 atm, are calculated using transition state theory (TST) and Rice-Ramsberger-Kassel-Marcus/Master-Equation (RRKM/ME) theory taking asymmetric Eckart tunneling corrections and the one-dimensional hindered rotor approximation into consideration. The rate rules are obtained by averaging the rate constants of the representative reactions of this class. These rate rules can greatly assist in constructing more accurate low-temperature combustion mechanisms for normal-alkyl cyclohexanes.

3.
BMC Genomics ; 24(1): 87, 2023 Feb 24.
Article in English | MEDLINE | ID: mdl-36829121

ABSTRACT

BACKGROUND: Facility cultivation is widely applied to meet the increasing demand for high yield and quality, with light intensity and light quality being major limiting factors. However, how changes in the light environment affect development and quality are unclear in garlic. When garlic seedlings are grown, they can also be exposed to blanching culture conditions of darkness or low-light intensity to ameliorate their appearance and modify their bioactive compounds and flavor. RESULTS: In this study, we determined the quality and transcriptomes of 14-day-old garlic and blanched garlic seedlings (green seedlings and blanched seedlings) to explore the mechanisms by which seedlings integrate light signals. The findings revealed that blanched garlic seedlings were taller and heavier in fresh weight compared to green garlic seedlings. In addition, the contents of allicin, cellulose, and soluble sugars were higher in the green seedlings. We also identified 3,872 differentially expressed genes between green and blanched garlic seedlings. The Kyoto Encyclopedia of Genes and Genomes analysis suggested enrichment for plant-pathogen interactions, phytohormone signaling, mitogen-activated protein kinase signaling, and other metabolic processes. In functional annotations, pathways related to the growth and formation of the main compounds included phytohormone signaling, cell wall metabolism, allicin biosynthesis, secondary metabolism and MAPK signaling. Accordingly, we identified multiple types of transcription factor genes involved in plant-pathogen interactions, plant phytohormone signaling, and biosynthesis of secondary metabolites among the differentially expressed genes between green and blanched garlic seedlings. CONCLUSIONS: Blanching culture is one facility cultivation mode that promotes chlorophyll degradation, thus changing the outward appearance of crops, and improves their flavor. The large number of DEGs identified confirmed the difference of the regulatory machinery under two culture system. This study increases our understanding of the regulatory network integrating light and darkness signals in garlic seedlings and provides a useful resource for the genetic manipulation and cultivation of blanched garlic seedlings.


Subject(s)
Garlic , Garlic/genetics , Plant Growth Regulators/metabolism , Disulfides/metabolism , Sulfinic Acids , Transcriptome , Seedlings/genetics , Gene Expression Regulation, Plant
4.
Hum Brain Mapp ; 44(8): 3084-3093, 2023 06 01.
Article in English | MEDLINE | ID: mdl-36919444

ABSTRACT

Despite burgeoning evidence for cortical hyperarousal in insomnia disorder, the existing results on electroencephalography spectral features are highly heterogeneous. Phase-amplitude coupling, which refers to the modulation of the low-frequency phase to a high-frequency amplitude, is probably a more sensitive quantitative measure for characterizing abnormal neural oscillations and explaining the therapeutic effect of repetitive transcranial magnetic stimulation in the treatment of patients with insomnia disorder. Sixty insomnia disorder patients were randomly divided into the active and sham treatment groups to receive 4 weeks of repetitive transcranial magnetic stimulation treatment. Behavioral assessments, resting-state electroencephalography recordings, and sleep polysomnography recordings were performed before and after repetitive transcranial magnetic stimulation treatment. Forty good sleeper controls underwent the same assessment. We demonstrated that phase-amplitude coupling values in the frontal and temporal lobes were weaker in Insomnia disorder patients than in those with good sleeper controls at baseline and that phase-amplitude coupling values near the intervention area were significantly enhanced after active repetitive transcranial magnetic stimulation treatment. Furthermore, the enhancement of phase-amplitude coupling values was significantly correlated with the improvement of sleep quality. This study revealed the potential of phase-amplitude coupling in assessing the severity of insomnia disorder and the efficacy of repetitive transcranial magnetic stimulation treatment, providing new insights on the abnormal physiological mechanisms and future treatments for insomnia disorder.


Subject(s)
Sleep Initiation and Maintenance Disorders , Transcranial Magnetic Stimulation , Humans , Transcranial Magnetic Stimulation/methods , Sleep Initiation and Maintenance Disorders/therapy , Dorsolateral Prefrontal Cortex , Prefrontal Cortex/diagnostic imaging , Prefrontal Cortex/physiology , Electroencephalography/methods , Treatment Outcome
5.
Toxicol Appl Pharmacol ; 468: 116516, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37068611

ABSTRACT

Lung cancer remains a common malignant tumor causing death due to the rapid industrialization and serious pollution of the environment. The Von Willebrand Factor (vWF) protein is an endothelial marker and is widely used to diagnose cancer and other inflammations, however its exact mechanism of action remains largely unexplored. In particular, how it plays two opposing roles in tumor development is not clear. Our study aimed to the impact of endothelial-derived vWF on tumor development by co-culturing human umbilical vein endothelial cells (HUVECs) with lung cancer cells (95D and A549). A knockdown of endothelial-derived vWF assisted lung cancer cell in proliferation, migration and inhibited apoptosis in vitro, while overexpression of endothelial-derived vWF inhibited the proliferation, migration and induced apoptosis of lung cancer cells. The results of further experiments indicated that the vWF secreted by endothelial cells could affect lung cancer cell migration and apoptosis via its binding to integrin αvß3 on the surface of lung cancer cells. Furthermore, a novel finding was the fact that endothelial-derived vWF inhibited lung cancer cell apoptosis by phosphorylating ERK1/2. At the same time, we established experimental lung metastasis model and xenograft model in normal mice and vWF-/- mice, and found that knockout of vWF in mice significantly promoted lung cancer growth and metastasis. In conclusion, our research found that endothelial-derived vWF could directly combine to αvß3 on the exterior of A549 and 95D, thereby mediating lung cancer proliferation, migration and apoptosis and inhibiting the development of lung cancer.


Subject(s)
Lung Neoplasms , von Willebrand Factor , Humans , Mice , Animals , von Willebrand Factor/metabolism , MAP Kinase Signaling System , Lung Neoplasms/pathology , Lung/metabolism , Human Umbilical Vein Endothelial Cells/metabolism
6.
Oral Dis ; 2023 May 19.
Article in English | MEDLINE | ID: mdl-37203597

ABSTRACT

OBJECTIVE: The aim of this study was to investigate the effect of mammalian-enabled (Mena) on tongue squamous cell carcinoma (TSCC) metastasis and its mechanism. MATERIALS AND METHODS: Immunochemistry was performed to investigate the Mena and tumor-related markers expression, and its clinicopathological characteristics in 46 TSCC specimens. TSCC cell SCC9 and Cal27 untransfected or stable transfected with Mena overexpression and small interfering RNA were used to determine the role of Mena in cell proliferation, cell migration, invasion and metastasis, and EMT-related markers in vitro, and the effect of Mena on TSCC growth and metastasis through tumor-bearing and tumor metastasis immunodeficient mice models in vivo. RESULTS: Immunochemistry showed that the expression of Mena was significantly correlated with lymphatic metastasis and TNM stage, E-cadherin, Vimentin, and MMP2. Mena did not affect cell proliferation and colony formation in vitro, and tumor growth in vivo. However, it promoted cell migration and invasion in vitro, and TSCC metastasis in vivo. CONCLUSIONS: Mena expression is associated with lymphatic metastasis and tumor stage and promotes TSCC invasion and metastasis by inducing the EMT process. Thus, Mena may be a biomarker for prognosis and targeted therapy in TSCC patients.

7.
Oral Dis ; 2023 Dec 26.
Article in English | MEDLINE | ID: mdl-38148479

ABSTRACT

OBJECTIVES: To explore the role of fibrocytes in the recurrence and calcification of fibrous epulides. METHODS: Different subtypes of fibrous epulides and normal gingival tissue specimens were first collected for histological and immunofluorescence analyses to see if fibrocytes were present and whether they differentiated into myofibroblasts and osteoblasts upon stimulated by transforming growth factor-ß1 (TGF-ß1). Electron microscopy and elemental analysis were used to characterize the extracellular microenvironment in different subtypes of fibrous epulides. Human peripheral blood mononuclear cells (PBMCs) were subsequently isolated from in vitro models to mimic the microenvironment in fibrous epulides to identify whether TGF-ß1 as well as the calcium and phosphorus ion concentration in the extracellular matrix (ECM) of a fibrous epulis trigger fibrocyte differentiation. RESULTS: Fibrous epulides contain fibrocytes that accumulate in the local inflammatory environment and have the ability to differentiate into myofibroblasts or osteoblasts. TGF-ß1 promotes fibrocytes differentiation into myofibroblasts in a concentration-dependent manner, while TGF-ß1 stimulates the fibrocytes to differentiate into osteoblasts when combined with a high calcium and phosphorus environment. CONCLUSIONS: Our study revealed fibrocytes play an important role in the fibrogenesis and osteogenesis in fibrous epulis, and might serve as a therapeutic target for the inhibition of recurrence of fibrous epulides.

8.
Molecules ; 28(18)2023 Sep 14.
Article in English | MEDLINE | ID: mdl-37764388

ABSTRACT

The concerted elimination reaction class of peroxyl-hydroperoxyl alkyl radicals (•OOQOOH) plays a crucial role in the low-temperature combustion of normal-alkyl cyclohexanes. The generation of the relatively unreactive HO2 radicals in this reaction is one of the factors leading to the negative temperature coefficient (NTC) behavior, which hinders the low-temperature oxidation of normal-alkyl cyclohexanes. In this study, 44 reactions are selected and divided into 4 different subclasses according to the nature of the carbon atom where the H atom is eliminated and the reaction center position. Utilizing the CBS-QB3 method, we compute the energy barriers for the concerted elimination reactions of peroxyl-hydroperoxyl alkyl radicals. Following this, we assess both the high-pressure limit and pressure-dependent rate constants for all reactions by applying TST and RRKM/ME theory. These calculations allow for the development of rate rules, which come to fruition through an averaging process involving the rate constants of representative reactions within each subclass. Our work provides accurate rate constants and rate rules for this reaction class, which can aid in constructing more accurate combustion mechanisms for normal-alkyl cyclohexanes.

9.
Br J Dermatol ; 187(6): 936-947, 2022 12.
Article in English | MEDLINE | ID: mdl-35862273

ABSTRACT

BACKGROUND: The key pathophysiological changes in androgenetic alopecia (AGA) are limited to hair follicles (HFs) in frontal and vertex regions, sparing the occipital region. OBJECTIVES: To identify biological differences among HF subpopulations. METHODS: Paired vertex and occipital HFs from 10 male donors with AGA were collected for RNA sequencing assay. Furthermore, HF and cell experiments were conducted on the identified key genes to reveal their roles in AGA. RESULTS: Transcriptome profiles revealed that 506 mRNAs, 55 microRNAs and 127 long noncoding RNAs were differentially expressed in the AGA vertex HFs. Pathway analysis of mRNAs and microRNAs revealed involvement of the hypoxia-inducible factor (HIF)-1, Wnt/ß-catenin, and focal adhesion pathways. Differential expression of HIF-1 prolyl hydroxylase enzymes (EGLN1, EGLN3) and Wnt/ß-catenin pathway inhibitors (SERPINF1, SFRP2) was experimentally validated. In vitro studies revealed that reduction of EGLN1, EGLN3, SERPINF1 and SFRP2 stimulated proliferation of dermal papilla cells. Ex vivo HF studies showed that downregulation of EGLN1, EGLN3 and SERPINF1 promoted HF growth, postponed HF catagen transition, and prolonged the anagen stage, suggesting that these genes may be potentially utilized as therapeutic targets for AGA. CONCLUSIONS: We characterized key transcriptome changes in male AGA HFs, and found that HIF-1 pathway-related genes (EGLN1, EGLN3) and Wnt pathway inhibitors (SERPINF1, SFRP2) may play important roles in AGA. What is already known about this topic? Multiple differentially expressed genes and signalling pathways have been found between hair follicles (HFs) in the balding area (frontal and vertex regions) and nonbalding area (occipital region) of individuals with androgenetic alopecia (AGA). A whole-transcriptome atlas of the vertex and occipital region is lacking. What does this study add? We identified a number of differentially expressed genes and pathways between balding vertex and nonbalding occipital AGA HFs by using whole-transcriptome analyses. We identified pathways not previously reported in AGA, such as the hypoxia-inducible factor (HIF)-1 signalling pathway. We verified that HIF-1 pathway-related genes (EGLN1, EGLN3) and Wnt pathway inhibitors (PEDF, SFRP2) played important roles in dermal papilla cell activity, hair growth and the hair cycle. What is the translational message? The EGLN1, EGLN3, SERPINF1 and SFRP2 genes may be potentially utilized as therapeutic targets for AGA.


Subject(s)
Alopecia , Hypoxia-Inducible Factor 1 , MicroRNAs , Wnt Signaling Pathway , Humans , Male , Alopecia/genetics , beta Catenin/metabolism , Gene Expression Profiling , Hair Follicle/metabolism , Hypoxia-Inducible Factor 1/genetics , Hypoxia-Inducible Factor 1/metabolism , MicroRNAs/metabolism , RNA, Messenger/metabolism , Wnt Signaling Pathway/genetics
10.
Phys Chem Chem Phys ; 24(39): 24362-24382, 2022 Oct 12.
Article in English | MEDLINE | ID: mdl-36178471

ABSTRACT

The analysis of the leading active molecular motions in the on-the-fly trajectory surface hopping simulation provides the essential information to understand the geometric evolution in nonadiabatic dynamics. When the ring deformation is involved, the identification of the key active coordinates becomes challenging. A "hierarchical" protocol based on the dimensionality reduction and clustering approaches is proposed for the automatic analysis of the ring deformation in the nonadiabatic molecular dynamics. The representative system keto isocytosine is taken as the prototype to illustrate this protocol. The results indicate that the current hierarchical analysis protocol is a powerful way to clearly clarify both the major and minor active molecular motions of the ring distortion in nonadiabatic dynamics.


Subject(s)
Molecular Dynamics Simulation , Cluster Analysis , Principal Component Analysis
11.
Dermatol Ther ; 35(8): e15657, 2022 08.
Article in English | MEDLINE | ID: mdl-35726636

ABSTRACT

Axillary osmidrosis (AO) and primary hyperhidrosis (PH) are common diseases, but there are still difficulties in treatment. Microwave therapy may become a new method. In order to evaluate long-time efficacy of patients with AO or PH treated by microwave and to discuss possible mechanism of microwave therapy by combining results of clinical and pathological, the study was carried out. Ten AO or PH patients with moderate or severe level were selected as subjects, and each subject received microwave treatment of bilateral armpits. The follow-up period lasted 2 years, and the changes of perspiration and odor were evaluated in subjective and objective ways. Each subject took skin biopsy in the treatment area before and after treatment or each follow-up. Hematoxylin-eosin and immunohistochemical staining were performed. Both subjective and objective index reflected the significant improvement of AO and PH after treatment (p < 0.05). Dermatology life quality index score decreased by 10.4 ± 4.6 (p < 0.05). The number of apocrine glands decreased significantly after treatment, and most of them changed from secretory phase to quiescent phase. In conclusion, microwave therapy can destroy apocrine sweat glands, reduce number of functional glands, so as to improve symptoms of AO and PH and elevate quality of life, which is safe, effective, and stable.


Subject(s)
Hyperhidrosis , Microwaves , Axilla/pathology , Humans , Hyperhidrosis/diagnosis , Hyperhidrosis/radiotherapy , Microwaves/adverse effects , Quality of Life , Treatment Outcome
12.
Acta Pharmacol Sin ; 43(6): 1430-1440, 2022 Jun.
Article in English | MEDLINE | ID: mdl-34654876

ABSTRACT

Transient receptor potential channel TRPV4 and nicotinamide adenine dinucleotide phosphate oxidase (Nox2) are involved in oxidative stress that increases endothelial permeability. It has been shown that obesity enhances the physical association of TRPV4 and Nox2, but the role of TRPV4-Nox2 association in obesity has not been clarified. In this study we investigated the function of TRPV4-Nox2 complex in reducing oxidative stress and regulating abnormal vascular permeability in obesity. Obesity was induced in mice by feeding a high-fat diet (HFD) for 14 weeks. The physical interaction between TRPV4 and Nox2 was measured using FRET, co-immunoprecipitation and GST pull-down assays. The functional interaction was measured by rhodamine phalloidin, CM-H2DCFDA in vitro, the fluorescent dye dihydroethidium (DHE) staining assay, and the Evans blue permeability assay in vivo. We demonstrated that TRPV4 physically and functionally associated with Nox2, and this physical association was enhanced in aorta of obese mice. Furthermore, we showed that interrupting TRPV4-Nox2 coupling by TRPV4 knockout, or by treatment with a specific Nox2 inhibitor Nox2 dstat or a specific TRPV4 inhibitor HC067046 significantly attenuated obesity-induced ROS overproduction in aortic endothelial cells, and reversed the abnormal endothelial cytoskeletal structure. In order to discover small molecules disrupting the over-coupling of TPRV4 and Nox2 in obesity, we performed molecular docking analysis and found that compound M12 modulated TRPV4-Nox2 association, reduced ROS production, and finally reversed disruption of the vascular barrier in obesity. Together, this study, for the first time, provides evidence for the TRPV4 physically interacting with Nox2. TRPV4-Nox2 complex is a potential drug target in improving oxidative stress and disruption of the vascular barrier in obesity. Compound M12 targeting TRPV4-Nox2 complex can improve vascular barrier function in obesity.


Subject(s)
Capillary Permeability , TRPV Cation Channels , Animals , Endothelial Cells/metabolism , Mice , Mice, Obese , Molecular Docking Simulation , Obesity/complications , Reactive Oxygen Species/metabolism , TRPV Cation Channels/metabolism
13.
J Environ Manage ; 304: 114230, 2022 Feb 15.
Article in English | MEDLINE | ID: mdl-34883437

ABSTRACT

This study conducts a life cycle environmental and economic quantification comparison of urban runoff source control facilities (URSCFs) through construction and operation stages in two urban functional regions (i.e., residential area and campus). From the environmental perspective, URSCFs construction in residential area has both higher environmental impacts and benefits than that in campus. The operation stage of URSCFs can observe significant benefit for both residential area and campus. We then develop a set of monetized method to make a comprehensive benefit evaluation (i.e., environmental, economic, and social benefit) of URSCFs. Overall, the two areas have payback time less than thirteen years for their investment which is acceptable when compared with the assumed total service period (30 years). Specifically, the payback time of campus is 5.62 years and residential area is 12.44 years. This implies that the campus has great potential to achieve high cost-benefit ratio and thus the Sponge City construction in campus can implement URSCFs with less engineering and material consumption due to its more spacious site than residential area with high building density. For both residential area and campus, permeable pavement has the highest environmental impact and economic cost because of the concrete consumption. Thus, we recommend that it should be cautious of the construction of concrete permeable pavement and find environmentally and economically alternatives in future URSCFs projects.


Subject(s)
Environment , Environmental Pollution/prevention & control , Cities , Cost-Benefit Analysis , Environmental Pollution/economics
14.
J Mol Cell Cardiol ; 157: 66-76, 2021 08.
Article in English | MEDLINE | ID: mdl-33932464

ABSTRACT

Obesity induces inflammation and oxidative stress, and ultimately leads to vasodilatory dysfunction in which Transient receptor potential vanilloid type 4 (TRPV4) and Nicotinamide Adenine Dinucleotide Phosphate Oxidase (Nox2) have been reported to be involved. However, little attention has been paid to the role of the TRPV4-Nox2 complex in these problems. The purpose of this study was to figure out the role of the TRPV4-Nox2 complex in obesity-induced inflammation, oxidative stress, and vasodilatory dysfunction. Using fluorescence resonance energy transfer and immunoprecipitation assays, we found enhanced TRPV4 and Nox2 interactions in obese mice. Using q-PCR, fluorescent dye dihydroethidium staining, and myotonic techniques, we found that obesity caused inflammation, oxidative stress, and vasodilatory dysfunction. Using adeno-associated viruses, we found that enhancement or attenuation of TRPV4-Nox2 interaction altered the vaso-function. Based on these findings, we found a small-molecule drug, M12, that interrupted the TRPV4-Nox2 interaction, thereby reducing inflammatory factors and reactive oxygen species production and helping to restore the vasodilatory function. In summary, our results revealed a new mechanism by which obesity-induced inflammation, oxidative stress, and vasodilatory dysfunction is caused by enhanced TRPV4-Nox2 interactions. Using M12 to interrupt the TRPV4-Nox2 interaction may have anti-inflammatory and anti-oxidative stress effects and help restore vasodilatory function and thus provide a new therapeutic approach to obesity.


Subject(s)
Endothelium, Vascular/metabolism , Inflammation/etiology , Inflammation/metabolism , NADPH Oxidase 2/metabolism , Reactive Oxygen Species/metabolism , TRPV Cation Channels/metabolism , Animals , Biomarkers , Disease Models, Animal , Disease Susceptibility , Endothelial Cells/metabolism , Inflammation/pathology , Inflammation Mediators/metabolism , Mice , Mice, Knockout , Mice, Obese , Mutation , NADPH Oxidase 2/genetics , Obesity/complications , Obesity/metabolism , Oxidative Stress , Protein Binding/drug effects , TRPV Cation Channels/genetics , Vasodilation/genetics
15.
J Neuroinflammation ; 18(1): 286, 2021 Dec 10.
Article in English | MEDLINE | ID: mdl-34893068

ABSTRACT

BACKGROUND: TREM2 is a microglial receptor genetically linked to the risk for Alzheimer's disease (AD). The cerebrospinal fluid (CSF) levels of soluble TREM2 (sTREM2) have emerged as a valuable biomarker for the disease progression in AD and higher CSF levels of sTREM2 are linked to slower cognitive decline. Increasing sTREM2 in mouse models of amyloidosis reduces amyloid-related pathology through modulating microglial functions, suggesting a beneficial role of sTREM2 in microglia biology and AD pathology. METHODS: In the current study, we performed serial C- and N-terminal truncations of sTREM2 protein to define the minimal sequence requirement for sTREM2 function. We initially assessed the impacts of sTREM2 mutants on microglial functions by measuring cell viability and inflammatory responses. The binding of the sTREM2 mutants to oligomeric Aß was determined by solid-phase protein binding assay and dot blot assay. We further evaluated the impacts of sTREM2 mutants on amyloid-related pathology by direct stereotaxic injection of sTREM2 proteins into the brain of 5xFAD mice. RESULTS: We found that both sTREM2 fragments 41-81 and 51-81 enhance cell viability and inflammatory responses in primary microglia. However, the fragment 51-81 exhibited impaired affinity to oligomeric Aß. When administrated to the 5xFAD mice brain, the sTREM2 fragment 41-81, but not 51-81, increased the number of plaque-associated microglia and reduced the plaque deposition. Interestingly, the fragment 41-81 was more efficient than the physiological form of sTREM2 in ameliorating Aß-related pathology. CONCLUSIONS: Our results indicate that the interaction of sTREM2 truncated variants with Aß is essential for enhancing microglial recruitment to the vicinity of an amyloid plaque and reducing the plaque load. Importantly, we identified a 41-amino acid sequence of sTREM2 that is sufficient for modulating microglial functions and more potent than the full-length sTREM2 in reducing the plaque load and the plaque-associated neurotoxicity. Taken together, our data provide more insights into the mechanisms underlying sTREM2 function and the minimal active sTREM2 sequence represents a promising candidate for AD therapy.


Subject(s)
Amyloidosis/genetics , Amyloidosis/pathology , Brain/pathology , Membrane Glycoproteins/genetics , Microglia/pathology , Phenotype , Receptors, Immunologic/genetics , Amino Acid Sequence , Animals , Cells, Cultured , HEK293 Cells , Humans , Mice
16.
J Biol Chem ; 294(1): 28-37, 2019 01 04.
Article in English | MEDLINE | ID: mdl-30413532

ABSTRACT

Ischemia-related diseases are a leading cause of death worldwide, and promoting therapeutic angiogenesis is key for effective recovery from hypoxia-ischemia. Given the limited success of angiogenic factors, such as vascular endothelial growth factor, in clinical trials, it is important to find more promising angiogenic targets. Here, using both cell- and tissue-based assays and a mouse model of injury-induced ischemia, we investigated the involvement of the transient receptor potential canonical 5 (TRPC5) ion channel in angiogenesis and the effects of a TRPC5 activator, the Food and Drug Administration-approved drug riluzole, on recovery from ischemic injury. We demonstrate that TRPC5 is involved in endothelial cell sprouting, angiogenesis, and blood perfusion in an oxygen-induced retinopathy model and a hind limb ischemia model. We found a potential regulatory link between nuclear factor of activated T cell isoform c3 and angiopoietin-1 that could provide the mechanistic basis for the angiogenic function of TRPC5. Importantly, treatment with riluzole, which can activate TRPC5 in endothelial cells, improved recovery from ischemia in mice. Our study reveals TRPC5 as a potential angiogenic target and suggests riluzole as a promising drug for managing ischemic diseases.


Subject(s)
Endothelial Cells/metabolism , Ischemia/metabolism , Neovascularization, Pathologic/metabolism , Retinal Diseases/metabolism , TRPC Cation Channels/metabolism , Animals , Disease Models, Animal , Endothelial Cells/pathology , HEK293 Cells , Humans , Ischemia/genetics , Ischemia/pathology , Ischemia/physiopathology , Mice , Mice, Knockout , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/pathology , Neovascularization, Pathologic/physiopathology , Retinal Diseases/genetics , Retinal Diseases/pathology , Retinal Diseases/physiopathology , Riluzole/pharmacology , TRPC Cation Channels/antagonists & inhibitors , TRPC Cation Channels/genetics
17.
Biochem Biophys Res Commun ; 501(2): 520-526, 2018 06 22.
Article in English | MEDLINE | ID: mdl-29750961

ABSTRACT

Apolipoprotein M (ApoM) is a sphingosine 1-phosphate (S1P) carrier involved in the regulation of S1P. Signaling pathways involving sphingosine kinases (SphKs) and S1P-S1P receptors (S1PRs) play important roles in the oncogenesis of multiple cancers including non-small cell lung cancer (NSCLC). In the present study we have clarified the potential roles of ApoM on the oncogenesis process of NSCLC cells. We detected the ApoM expression in NSCLC tissues and further analyzed its clinical significance. Moreover, we determined effects of ApoM overexpression on tumor cellular behaviours of NSCLC in vitro and in vivo. Our results demonstrated that ApoM protein mass were clearly higher in the NSCLC tissues than in non-NSCLS tissues. Overexpression of ApoM could promote NSCLC cell proliferation and invasion in vitro and tumor growth in vivo, which might be via upregulating S1PR1 and activating the ERK1/2 and PI3K/AKT signaling pathways. It is concluded that up-regulation of ApoM in NSCLC might be associated with the tumor induced inflammation and tumor microenvironment as well as promoting oncogenesis of NSCLC. Further study needs to elucidate the underlying mechanisms.


Subject(s)
Apolipoproteins M/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Neoplasm Invasiveness/pathology , Receptors, Lysosphingolipid/metabolism , Signal Transduction , Aged , Animals , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Cell Proliferation , Female , Humans , MAP Kinase Signaling System , Male , Mice, Inbred BALB C , Middle Aged , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Sphingosine-1-Phosphate Receptors
19.
Clin Sci (Lond) ; 131(3): 227-237, 2017 02 01.
Article in English | MEDLINE | ID: mdl-27895148

ABSTRACT

Transient receptor potential channel 5 (TrpC5) is a member of the TrpC subgroup, and it forms a receptor-activated, non-selective Ca2+ channel. The architecture of the TrpC5 channel is poorly understood. In the present study, we report that TrpC5 is a key factor in regulating differentiation in colorectal cancer (CRC). Through a study of specimens from a large cohort of patients with CRC, we found that TrpC5 was highly expressed and its cellular level correlated with tumour grade. We showed further that up-regulated TrpC5 caused a robust rise in intracellular calcium concentration [Ca2+]i, increased Wnt5a expression and the nuclear translocation of ß-catenin, leading to a reduction in cancer differentiation and an increase in cancer cell stemness. Notably, patients with tumours that expressed high levels of TrpC5 showed significantly poorer disease-free and overall survival. Therefore, our findings suggest that TrpC5 is an independent adverse prognostic factor for death in CRC, reducing differentiation through the Ca2+/Wnt5a signalling pathway.


Subject(s)
Calcium Signaling , Carcinoma/metabolism , Colorectal Neoplasms/metabolism , TRPC Cation Channels/metabolism , Wnt-5a Protein/metabolism , Animals , Caco-2 Cells , Carcinoma/diagnosis , Carcinoma/pathology , Cell Differentiation , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/pathology , HT29 Cells , Humans , Mice, Inbred BALB C , Mice, Nude , Neoplasm Grading , Prognosis , beta Catenin/metabolism
20.
Exp Brain Res ; 235(3): 941-948, 2017 03.
Article in English | MEDLINE | ID: mdl-27942764

ABSTRACT

Aphasia is a devastating neurological condition affecting a person's ability to communicate and reintegrate into the society. It may occur in 20% or more of patients after stroke. The recovery of language function is accompanied by brain reorganization, and identifying the inter-hemispheric interaction post-stroke will conduce to more targeted treatments. Previous studies suggested that robust homotopic resting-state functional connectivity is a key characteristic of the brain's intrinsic functional architecture, and communication between the left and right cerebral hemispheres is important for language processing. In this study, voxel-mirrored homotopic connectivity (VMHC) was used to examine the inter-hemispheric resting-state functional connectivity (RSFC) differences between 37 patients with acute lacunar stroke in the left hemisphere and 28 healthy controls. Besides, correlation analyses were carried out to investigate the relationship between VMHC values of brain regions showing abnormal inter-hemispheric RSFC and clinical variables [i.e., aphasia quotient (AQ) scores, National Institutes of Health Stroke Scale (NIHSS) and Mini-Mental State Examination of patients]. Compared with healthy controls, patients showed significantly increased VMHC in the pars orbitalis of the inferior frontal gyrus, anterior part of the superior temporal gyrus (STG) and lingual gyrus. No brain region showed decreased VMHC in the patient group than in the healthy control group. The AQ scores were negatively correlated with VMHC values in the STG. NIHSS scores were positively correlated with VMHC values in the lingual gyrus. We hope these results could shed new insights into the pathology of aphasia in patients with acute lacunar stroke.


Subject(s)
Aphasia , Brain/diagnostic imaging , Functional Laterality/physiology , Rest , Stroke, Lacunar/complications , Adult , Aged , Aphasia/diagnostic imaging , Aphasia/etiology , Aphasia/pathology , Diffusion Magnetic Resonance Imaging , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Neural Pathways/diagnostic imaging , Oxygen/blood , Severity of Illness Index , Stroke, Lacunar/diagnostic imaging
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