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1.
Biomed Res ; 45(2): 67-76, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38556264

RESUMO

We previously reported that tenascin-X (Tnxb) aggravates hepatic fibrosis in mice fed a high-fat and high-cholesterol diet with high levels of phosphorus and calcium (HFCD). In this study, we investigated Tnxb expression in livers with fibrosis caused by administration of a methionine-chorine-deficient (MCD) diet in mice. Whole transcriptome analysis showed that Tnxb was one of the genes with increased expression in livers of MCD diet-fed mice compared with that in livers of normal diet (ND)-fed mice. In microarray and subsequent microRNA (miRNA) network analyses, miR-378a-5p and miR-486-5p were identified in livers of MCD diet-fed mice as downregulated miRNAs, which have their predicted target sites in the 3' untranslated region of Tnxb mRNA and might suppress the translation of Tnxb mRNA. RT-qPCR analyses of livers of MCD diet-fed mice compared with livers of ND-fed mice verified the upregulation of Tnxb and fibrosis-triggering genes and conversely the downregulation of miR-378a-5p and miR-486-5p. Overexpression of miR-378a-5p and miR-486-5p resulted in decreased level not only of the FLAG-tagged fibrinogen-like domain of Tnxb protein (FLAG-mTNX-FG) but also of endogenous Tnxb protein in murine cultured cells. These results indicate that expression of Tnxb is regulated by miR-378a-5p and miR-486-5p in hepatic fibrosis following MCD diet feeding.


Assuntos
Metionina , MicroRNAs , Tenascina , Camundongos , Animais , Colina , Cirrose Hepática/genética , MicroRNAs/genética , Dieta/efeitos adversos , Fibrose , Racemetionina , RNA Mensageiro , Camundongos Endogâmicos C57BL
2.
Sci Rep ; 13(1): 18490, 2023 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-37898719

RESUMO

Deficiency of an extracellular matrix glycoprotein tenascin-X (TNX) leads to a human heritable disorder Ehlers-Danlos syndrome, and TNX-deficient patients complain of chronic joint pain, myalgia, paresthesia, and axonal polyneuropathy. We previously reported that TNX-deficient (Tnxb-/-) mice exhibit mechanical allodynia and hypersensitivity to myelinated A-fibers. Here, we investigated the pain response of Tnxb-/- mice using pharmacological silencing of A-fibers with co-injection of N-(2,6-Dimethylphenylcarbamoylmethyl) triethylammonium bromide (QX-314), a membrane-impermeable lidocaine analog, plus flagellin, a toll-like receptor 5 (TLR5) ligand. Intraplantar co-injection of QX-314 and flagellin significantly increased the paw withdrawal threshold to transcutaneous sine wave stimuli at frequencies of 250 Hz (Aδ fiber responses) and 2000 Hz (Aß fiber responses), but not 5 Hz (C fiber responses) in wild-type mice. The QX-314 plus flagellin-induced silencing of Aδ- and Aß-fibers was also observed in Tnxb-/- mice. Co-injection of QX-314 and flagellin significantly inhibited the mechanical allodynia and neuronal activation of the spinal dorsal horn in Tnxb-/- mice. Interestingly, QX-314 alone inhibited the mechanical allodynia in Tnxb-/- mice, and it increased the paw withdrawal threshold to stimuli at frequencies of 250 Hz and 2000 Hz in Tnxb-/- mice, but not in wild-type mice. The inhibition of mechanical allodynia induced by QX-314 alone was blocked by intraplantar injection of a TLR5 antagonist TH1020 in Tnxb-/- mice. These results suggest that mechanical allodynia due to TNX deficiency is caused by the hypersensitivity of Aδ- and Aß-fibers, and it is induced by constitutive activation of TLR5.


Assuntos
Síndrome de Ehlers-Danlos , Hiperalgesia , Animais , Humanos , Camundongos , Síndrome de Ehlers-Danlos/complicações , Síndrome de Ehlers-Danlos/genética , Matriz Extracelular , Flagelina , Hiperalgesia/genética , Hiperalgesia/complicações , Fibras Nervosas Amielínicas , Tenascina/genética , Receptor 5 Toll-Like
3.
Exp Anim ; 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37821385

RESUMO

Genetic and environmental factors interact in a complex manner in the pathogenesis of essential hypertension in humans. Oxidative stress is considered one of the more important environmental factors. We used the spontaneously hypertensive rat (SHR) model to test whether continuous feeding with the antioxidant tempol reduces maternal oxidative stress during pregnancy and potentially contributes to the prevention of cardiovascular disease onset. Pregnant female rats were divided into control and tempol-treated groups. Tempol was continuously administered in the drinking water. The administration period lasted approximately 40 days from the confirmation of a vaginal plug until birth of the pups and their subsequent weaning. The blood pressure (BP) of each adult female was measured three times during pregnancy and post parturition. Milk was collected three times in the immediate postpartum period from nursing mother rats. Markers of oxidative stress were measured: 8-hydroxyl-2'-deoxyguanosine (8-OHdG) levels in milk during the experimental period, 8-OHdG levels and corticosterone levels in urine of adult and neonatal rats. The urinary level of 8-OHdG in the tempol-treated group was significantly lower than in the control group. Corticosterone levels were significantly lower in urine of neonatal rats from the tempol-treated group compared to the control group. 8-OHdG and corticosterone levels in milk of the tempol-treated group were significantly greater than in the control group. This study demonstrates that continuous administration of tempol to pregnant SHRs reduced maternal oxidative stress and contributed to reduced oxidative stress in neonatal rats.

4.
Front Genet ; 14: 1234804, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37712068

RESUMO

Classical-like Ehlers-Danlos syndrome (clEDS) is an autosomal recessive disorder caused by complete absence of tenascin-X resulting from biallelic variation in TNXB. Thus far, 50 patients from 43 families with biallelic TNXB variants have been identified. Accurate detection of TNXB variants is challenging because of the presence of the pseudogene TNXA, which can undergo non-allelic homologous recombination. Therefore, we designed a genetic screening system that is performed using similar operations to other next-generation sequencing (NGS) panel analyses and can be applied to accurately detect TNXB variants and the recombination of TNXA-derived sequences into TNXB. Using this system, we identified biallelic TNXB variants in nine unrelated clEDS patients. TNXA-derived variations were found in >75% of the current cohort, comparable to previous reports. The current cohort generally exhibited similar clinical features to patients in previous reports, but had a higher frequency of gastrointestinal complications (e.g., perforation, diverticulitis, gastrointestinal bleeding, intestinal obstruction, rectal/anal prolapse, and gallstones). This report is the first to apply an NGS-based screening for TNXB variants and represents the third largest cohort of clEDS, highlighting the importance of increasing awareness of the risk of gastrointestinal complications.

5.
Carbon Balance Manag ; 18(1): 8, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37199889

RESUMO

Discussion on reducing emissions from deforestation in developing countries began at the United Nations Framework Convention on Climate Change (UNFCCC) Conference of the Parties in 2005, and the agenda for "reducing emissions from deforestation and forest degradation, and the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries (REDD+)" was introduced under the UNFCCC. The REDD+ framework was developed with the expectation that it would significantly contribute to climate change mitigation at a relatively low cost and produce benefits for both developed and developing countries. Finance is a key element of REDD+ implementation, and many financial sources, approaches, and mechanisms have supported REDD+-related activities in various developing countries. However, the comprehensive challenges and lessons learned for REDD+ finance and its governance have not been fully explored. This paper reviews the relevant literature to understand the challenges for REDD+ finance and its governance in two areas-(1) REDD+ finance aligned with the UNFCCC and (2) REDD+-related finance outside the UNFCCC-which have developed differently and have different implications. This paper first identifies the six key elements of REDD+ finance and its governance across the two fields, and then reviews the related challenges and lessons learned with respect to public and private finance. The challenges for REDD+ finance and its governance aligned with the UNFCCC include enhancing the performance of REDD+ finance using mainly public finance, such as results-based finance and the jurisdictional approach. In contrast, the challenges regarding REDD+-related finance outside the UNFCCC include enhancing the engagement of the private sector in REDD+ finance, mainly targeting the project level, and the relationship between voluntary carbon markets and other investment and finance mechanisms. This paper also identifies the common challenges across REDD+ finance and its governance in the two fields. These challenges include the need to enhance linkages between REDD+ and other objectives, such as carbon neutrality/net-zero, deforestation-free supply chains, and nature-based solutions, as well as the need to develop learning systems for REDD+ finance.

6.
Ocul Surf ; 29: 131-149, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37209968

RESUMO

The structural composition, integrity and regular curvature of the cornea contribute to the maintenance of its transparency and vision. Disruption of its integrity caused by injury results in scarring, inflammation and neovascularization followed by losses in transparency. These sight compromising effects is caused by dysfunctional corneal resident cell responses induced by the wound healing process. Upregulation of growth factors/cytokines and neuropeptides affect development of aberrant behavior. These factors trigger keratocytes to first transform into activated fibroblasts and then to myofibroblasts. Myofibroblasts express extracellular matrix components for tissue repair and contract the tissue to facilitate wound closure. Proper remodeling following primary repair is critical for restoration of transparency and visual function. Extracellular matrix components contributing to the healing process are divided into two groups; a group of classical tissue structural components and matrix macromolecules that modulate cell behaviors/activities besides being integrated into the matrix structure. The latter components are designated as matricellular proteins. Their functionality is elicited through mechanisms which modulate the scaffold integrity, cell behaviors, activation/inactivation of either growth factors or cytoplasmic signaling regulation. We discuss here the functional roles of matricellular proteins in mediating injury-induced corneal tissue repair. The roles are described of major matricellular proteins, which include tenascin C, tenascin X and osteopontin. Focus is directed towards dealing with their roles in modulating individual activities of wound healing-related growth factors, e. g., transforming growth factor ß (TGF ß). Modulation of matricellular protein functions could encompass a potential novel strategy to improve the outcome of injury-induced corneal wound healing.


Assuntos
Lesões da Córnea , Tenascina , Humanos , Tenascina/metabolismo , Osteopontina/metabolismo , Cicatrização/fisiologia , Córnea/metabolismo , Lesões da Córnea/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo
7.
Front Genet ; 14: 1107787, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007968

RESUMO

Tenascin-X (TNX) is an extracellular matrix glycoprotein for which a deficiency results in a recessive form of classical-like Ehlers-Danlos syndrome (clEDS), a heritable connective tissue disorder with hyperextensible skin without atrophic scarring, joint hypermobility, and easy bruising. Notably, patients with clEDS also suffer from not only chronic joint pain and chronic myalgia but also neurological abnormalities such as peripheral paresthesia and axonal polyneuropathy with high frequency. By using TNX-deficient (Tnxb -/-) mice, well-known as a model animal of clEDS, we recently showed that Tnxb -/- mice exhibit hypersensitivity to chemical stimuli and the development of mechanical allodynia due to the hypersensitization of myelinated A-fibers and activation of the spinal dorsal horn. Pain also occurs in other types of EDS. First, we review the underlying molecular mechanisms of pain in EDS, especially that in clEDS. In addition, the roles of TNX as a tumor suppressor protein in cancer progression have been reported. Recent in silico large-scale database analyses have shown that TNX is downregulated in various tumor tissues and that high expression of TNX in tumor cells has a good prognosis. We describe what is so far known about TNX as a tumor suppressor protein. Furthermore, some patients with clEDS show delayed wound healing. Tnxb -/- mice also exhibit impairment of epithelial wound healing in corneas. TNX is also involved in liver fibrosis. We address the molecular mechanism for the induction of COL1A1 by the expression of both a peptide derived from the fibrinogen-related domain of TNX and integrin α11.

8.
Mol Clin Oncol ; 18(3): 24, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36844465

RESUMO

A 60-year-old woman presented with a 3-year history of a slow-growing, painless mass in their left parotid gland. Ultrasonography revealed a well-circumscribed, lobulated, hypoechoic mass measuring 19x12x10 mm in the left parotid gland. Computed tomography revealed a well-circumscribed, solid mass with homogeneous enhancement. Fluorodeoxyglucose-positron emission tomography revealed uptake by the tumor but no uptake in other organs, including the nasopharynx. The patient underwent superficial parotidectomy with adequate safety margins and selective neck dissection followed by radiotherapy. No facial paralysis or recurrence of the tumor had been observed as of 20 months post-operation. Histologically, the tumor was composed of sheets of syncytial cancer cells with prominent nucleoli in a dense lymphoplasmacytic background. Epstein-Barr virus (EBV)-encoded RNA in situ hybridization was diffusely positive in the tumor cells. These findings indicated that the tumor was an EBV-associated lymphoepithelial carcinoma. Metastasis, especially from the nasopharynx, was excluded endoscopically and radiologically. Targeted next-generation sequencing of 160 cancer-related genes using the surgical specimen revealed no mutations, including known significant mutations detected in EBV-associated nasopharyngeal carcinoma.

9.
Mol Med Rep ; 26(5)2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36069233

RESUMO

Extracellular matrix tenascin­X (TNX) is the largest member of the tenascin family. Our previous study demonstrated that TNX was involved in hepatic dysfunction, including fibrosis, in mice that were administered a high­fat and high­cholesterol diet with high levels of phosphorus and calcium. The present study investigated whether overexpression of both the fibrinogen domain of TNX (TNX­FG) and integrin α11, one of the TNX cell surface receptors, induces in vitro fibrosis in LX­2 human hepatic stellate cells. Overexpression of both a 15­amino acid peptide (hTNX­FGFFFF) derived from the TNX­FG domain and integrin α11 induced the expression of type I collagen α1 chain (COL1A1). Treatment with verteporfin [YAP (Yes­associated protein) inhibitor] attenuated the elevated COL1A1 expression elicited by overexpression of both hTNX­FGFFFF and integrin α11. In addition, small interfering RNA­mediated knockdown of YAP1 resulted in a decrease in COL1A1 expression induced by overexpression of both hTNX­FGFFFF and integrin α11. These results indicated that overexpression of both hTNX­FGFFFF and integrin α11 induced COL1A1 expression via the YAP signaling pathway.


Assuntos
Integrinas , Tenascina , Aminoácidos , Animais , Matriz Extracelular/metabolismo , Fibrinogênio , Fibrose , Humanos , Cadeias alfa de Integrinas/metabolismo , Integrinas/metabolismo , Camundongos , Peptídeos , Tenascina/genética
10.
Sci Rep ; 12(1): 15253, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36085349

RESUMO

Basket clam soup, a popular Asian dish, is prepared by boiling clams in hot water. The soup is generally cloudy, and it is considered that increased cloudiness enhances taste. However, the composition of the whitening ingredients and their association with taste enhancement remains unclear. In this study, we aimed to identify the components contributing to the white colour of the boiled soup. The white component upon precipitation with trichloroacetic acid reacted positively with ninhydrin, indicating the presence of proteins. The separation of proteins using sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed an intense band of size 33 kDa. Peptide mass fingerprinting of the identified protein using matrix-assisted laser desorption/ionisation-time-of-flight tandem mass spectrometry revealed the protein as tropomyosin. To validate the involvement of tropomyosin in the turbidity of the soup, tropomyosin was expressed and extracted from Escherichia coli. As expected, the purified protein suspended in water resulted in turbid appearance. To determine whether lipids have any association with the observed cloudiness of the soup, the amounts of fatty acids were measured. The proportion of estimated fatty acids was very low compared to that of proteins. Overall, we identified the major component contributing to soup cloudiness as tropomyosin forming micelles.


Assuntos
Furunculose , Tropomiosina , Animais , Cor , Escherichia coli , Ácidos Graxos , Micelas , Alimentos Marinhos , Frutos do Mar , Água
11.
FEBS Open Bio ; 12(10): 1788-1796, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35856166

RESUMO

Effective amelioration of type II diabetes requires therapies that increase both glucose uptake activity per cell and skeletal muscle mass. Myristic acid (14:0) increases diacylglycerol kinase (DGK) δ protein levels and enhances glucose uptake in myotubes in a DGKδ-dependent manner. However, it is still unclear whether myristic acid treatment affects skeletal muscle mass. In this study, we found that myristic acid treatment increased the protein level of ß-tubulin, which constitutes microtubules and is closely related to muscle mass, in C2C12 myotubes but not in the proliferation stage in C2C12 myoblasts. However, lauric (12:0), palmitic (16:0) and oleic (18:1) acids failed to affect DGKδ and ß-tubulin protein levels in C2C12 myotubes. Moreover, knockdown of DGKδ by siRNA significantly inhibited the increased protein level of ß-tubulin in the presence of myristic acid, suggesting that the increase in ß-tubulin protein by myristic acid depends on DGKδ. These results indicate that myristic acid selectively affects ß-tubulin protein levels in C2C12 myotubes via DGKδ, suggesting that this fatty acid improves skeletal muscle mass in addition to increasing glucose uptake activity per cell.


Assuntos
Diabetes Mellitus Tipo 2 , Diacilglicerol Quinase , Diabetes Mellitus Tipo 2/metabolismo , Diacilglicerol Quinase/genética , Diacilglicerol Quinase/metabolismo , Diacilglicerol Quinase/farmacologia , Glucose/metabolismo , Humanos , Fibras Musculares Esqueléticas/metabolismo , Ácido Mirístico/farmacologia , RNA Interferente Pequeno/farmacologia , Tubulina (Proteína)/farmacologia
12.
Exp Anim ; 71(3): 347-355, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35264492

RESUMO

Hydrogen-rich water (HW) has been suggested to possess antioxidant properties of value in treatments of lifestyle diseases and for prevention of latent pathologies. To date, the potential benefits of HW against the deleterious effects of excessive salt intake and hypertension have not been investigated. Here, we first examined the effects of HW or HW supplemented with 0.1% ascorbic acid (HWA) on spontaneously hypertensive rats (SHR) that had been fed a normal diet. In comparison to control rats given distilled water (DW), we found that HW did not significantly influence systolic blood pressure (SBP) or diastolic blood pressure (DBP) in SHR; however, the increase in SBP and DBP were inhibited in the HWA group. Next, four groups of SHR were given DW, 0.1% ascorbic acid-added DW (DWA), HW, or HWA in combination with a 4% NaCl-added diet. SHR fed the 4% NaCl-added diet showed increased hypertension; HWA treatment resulted in a significant reduction in blood pressure. The HWA group tended to have lower plasma angiotensin II levels than the DW group. In addition, urinary volumes and urinary sodium levels were significantly lower in the HWA group than the DW group. Urinary isoprostane, an oxidative stress marker, was also significantly lower in the HWA group, suggesting that the inhibitory effect of HWA on blood pressure elevation was caused by a reduction in oxidative stress. These findings suggest a synergistic interaction between HW and ascorbic acid, and also suggest that HWA ingestion has potential for prevention of hypertension.


Assuntos
Ácido Ascórbico , Hipertensão , Animais , Ácido Ascórbico/farmacologia , Hidrogênio , Hipertensão/prevenção & controle , Ratos , Ratos Endogâmicos SHR , Cloreto de Sódio , Água
13.
Int J Mol Sci ; 24(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36614115

RESUMO

Alzheimer's disease (AD) is a common dementia disease in the elderly. To get a better understanding of the pathophysiology, we performed a proteomic analysis of the urine exosomes (U-exo) in AD model mice (J20). The polymer precipitation method was used to isolate U-exo from the urine of 3-month-old J20 and wild-type (WT) mice. Neuron-derived exosome (N-exo) was isolated from U-exo by immunoprecipitation. iTRAQ-based MALDI TOF MS/MS was used for proteomic analysis. The results showed that compared to WT, the levels of 61 and 92 proteins were increased in the J20 U-exo and N-exo, respectively. Gene ontology enrichment analysis demonstrated that the sphingolipid catabolic process, ceramide catabolic process, membrane lipid catabolic process, Aß clearance, and Aß metabolic process were highly enriched in U-exo and N-exo. Among these, Asah1 was shown to be the key protein in lipid metabolism, and clusterin, ApoE, neprilysin, and ACE were related to Aß metabolism and clearance. Furthermore, protein-protein interaction analysis identified four protein complexes where clusterin and ApoE participated as partner proteins. Thus, J20 U-exo and N-exo contain proteins related to lipid- and Aß-metabolism in the early stages of AD, providing a new insight into the underlying pathological mechanism of early AD.


Assuntos
Doença de Alzheimer , Exossomos , Camundongos , Animais , Camundongos Transgênicos , Peptídeos beta-Amiloides/metabolismo , Clusterina/metabolismo , Exossomos/metabolismo , Espectrometria de Massas em Tandem , Proteômica , Doença de Alzheimer/metabolismo , Apolipoproteínas E/metabolismo , Modelos Animais de Doenças , Precursor de Proteína beta-Amiloide/metabolismo
14.
Exp Anim ; 71(2): 150-160, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34789620

RESUMO

Housing conditions can affect the well-being of laboratory animals and thereby affect the outcomes of experiments. The appropriate environment is essential for the expression of natural behavior in animals. Here, we compared survival rates in four inbred mouse strains maintained under three different environmental conditions. Three mouse strains (C57BL/6J, C3H/HeN, and DBA/2J) housed under environmental enrichment (EE) conditions showed improved survival; however, EE did not alter the survival rate of the fourth strain, BALB/c. None of the strains showed significant differences in body weights or plasma corticosterone levels in the three environmental conditions. For BALB/c mice, the rates of debility were higher in the EE group. Interestingly, for C57BL/6J and C3H/HeN mice, the incidence of animals with alopecia was significantly lower in the EE groups than in the control group. It is possible that the enriched environment provided greater opportunities for sheltering in a secure location in which to avoid interactions with other mice. The cloth mat flooring used for the EE group was bitten and chewed by the mice. Our findings suggest that depending on the mouse strains different responses to EE are caused with regard to health and survival rates. The results of this study provide basic data for further studies on EE.


Assuntos
Habitação , Animais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Endogâmicos , Taxa de Sobrevida
15.
Lab Invest ; 101(6): 690-700, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33782532

RESUMO

The purpose of the study was to uncover the role of tenascin X in modulation of healing in mouse corneas subjected to epithelium debridement. Healing in corneas with an epithelial defect was evaluated at the levels of gene and protein expression. Wound healing-related mediators and inflammatory cell infiltration were detected by histology, immunohistochemistry and real-time RT-PCR. Tenascin X protein was upregulated in the wounded wild-type (WT) corneal epithelium. The lack of tenascin X impaired closure of an epithelial defect and accelerated infiltration of neutrophils into the wound periphery as compared to the response in WT tissue. Expression of wound healing-related proinflammatory and reparative components, i.e., interleukin-6, transforming growth factor ß, matrix metalloproteinases, were unaffected by the loss of tenascin X expression. Marked accumulation of malondialdehyde (a lipid peroxidation-derived product) was observed in KO healing epithelia as compared with its WT counterpart. Neutropenia induced by systemic administration of a specific antibody rescued the impairment of epithelial healing in KO corneas, with reduction of malondialdehyde levels in the epithelial cells. Finally, we showed that a chemical scavenging reactive oxygen species reversed the impairment of attenuation of epithelial repair with a reduction of tissue levels of malondialdehyde. In conclusion, loss of tenascin X prolonged corneal epithelial wound healing and increased neutrophilic inflammatory response to debridement in mice. Tenascin X contributes to the control of neutrophil infiltration needed to support the regenerative response to injury and prevent the oxidative stress mediators from rising to cytotoxic levels.


Assuntos
Córnea/imunologia , Infiltração de Neutrófilos , Espécies Reativas de Oxigênio/metabolismo , Tenascina/fisiologia , Cicatrização/imunologia , Animais , Córnea/metabolismo , Camundongos Knockout
16.
Front Immunol ; 11: 609752, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33335533

RESUMO

Tenascins are a family of multifunctional extracellular matrix (ECM) glycoproteins with time- and tissue specific expression patterns during development, tissue homeostasis, and diseases. There are four family members (tenascin-C, -R, -X, -W) in vertebrates. Among them, tenascin-X (TNX) and tenascin-C (TNC) play important roles in human pathologies. TNX is expressed widely in loose connective tissues. TNX contributes to the stability and maintenance of the collagen network, and its absence causes classical-like Ehlers-Danlos syndrome (clEDS), a heritable connective tissue disorder. In contrast, TNC is specifically and transiently expressed upon pathological conditions such as inflammation, fibrosis, and cancer. There is growing evidence that TNC is involved in inflammatory processes with proinflammatory or anti-inflammatory activity in a context-dependent manner. In this review, we summarize the roles of these two tenascins, TNX and TNC, in cardiovascular and inflammatory diseases and in clEDS, and we discuss the functional consequences of the expression of these tenascins for tissue homeostasis.


Assuntos
Doenças Cardiovasculares/metabolismo , Sistema Cardiovascular/metabolismo , Doenças do Tecido Conjuntivo/metabolismo , Inflamação/metabolismo , Tenascina/metabolismo , Animais , Homeostase/fisiologia , Humanos
17.
Biochimie ; 177: 13-24, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32791090

RESUMO

Diacylglycerol kinase (DGK) phosphorylates diacylglycerol to produce phosphatidic acid (PA). The η isozyme of DGK is abundantly expressed in C2C12 myoblasts. However, the role of DGKη in skeletal muscle cells remains unknown. In the present study, we showed that DGKη was downregulated at an early stage of myogenic differentiation. The knockdown of DGKη by siRNAs significantly inhibited C2C12 myoblast proliferation but did not inhibit differentiation. Moreover, the suppression of DGKη expression decreased the expression levels of mammalian target of rapamycin (mTOR), which is a key regulator of cell proliferation, and fatty acid synthase (FASN), which catalyzes the de novo synthesis of fatty acids for cell proliferation and is transcriptionally regulated via mTOR signaling. Furthermore, the knockdown of mTOR or raptor, which is a component of mTOR complex 1 (mTORC1), decreased the amount of FASN. These results indicate that DGKη regulates myoblast proliferation through the mTOR (mTORC1)-FASN pathway. Interestingly, the knockdown of mTOR reduced the expression levels of DGKη, implying mutual regulation between DGKη and mTOR. In DGKη-knockdown myoblasts, C30-C36-PA species, mTOR activators, were decreased, suggesting that the modulation of mTOR activity through these PA species also plays an important role in myoblast proliferation.


Assuntos
Diacilglicerol Quinase/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Diferenciação Celular/genética , Proliferação de Células/genética , Diacilglicerol Quinase/genética , Diglicerídeos/metabolismo , Regulação para Baixo , Ácido Graxo Sintase Tipo I/biossíntese , Técnicas de Silenciamento de Genes , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Desenvolvimento Muscular/genética , Mioblastos/metabolismo , Ácidos Fosfatídicos/química , Ácidos Fosfatídicos/metabolismo , Fosforilação , Proteína Companheira de mTOR Insensível à Rapamicina/genética , Proteína Companheira de mTOR Insensível à Rapamicina/metabolismo , Proteína Regulatória Associada a mTOR/genética , Proteína Regulatória Associada a mTOR/metabolismo , Transdução de Sinais
18.
Sci Total Environ ; 740: 140155, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32569914

RESUMO

China's energy use has increased significantly in recent years with the country's rapid economic growth and large-scale urbanization. Therefore, air pollution has become a major issue. In this study, we conducted spatial autocorrelation and spatial panel regression analyses of sulfur dioxide (SO2) and nitrogen oxide (NOX) emissions using the panel data of 31 provincial-level administrative units in China during the period 2011-2017 to comprehensively understand the factors affecting air pollutant emissions. This study contributes to the literature by considering comprehensive factors and spatial effects in the panel-data econometric framework of the whole country of China. The analysis of spatial characteristics shows that during the study period, pollutant emissions in China declined, although emissions in northern regions were still relatively high. Furthermore, SO2 and NOX emissions showed significant positive spatial autocorrelations. The results of a fixed-effect spatial lag model showed that both socioeconomic and natural factors were statistically significant for air pollutant emissions, although the degree differed by the type of pollutant. The population, the urbanization rate, the share of added value of secondary industry, and heating and cooling degree days positively affected emissions, while population density, per-capita gross regional product, precipitation, and relative humidity negatively affected emissions. Based on these results, we have put forward suggestions to address the issue of air pollution and achieve environmental sustainability, such as the promotion of regional cooperation and a transition of the economic structure.

19.
Brain Res ; 1742: 146900, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32445714

RESUMO

Transplantation with mesenchymal stem cells (MSCs) has been reported to promote functional recovery in animal models of ischemic stroke. However, the molecular mechanisms underlying the therapeutic effects of MSC transplantation have been only partially elucidated. The purpose of this study was to comprehensively identify changes in brain proteins in rats treated with MSCs for ischemic stroke, and to explore the multi-target mechanisms of MSCs using a proteomics-based strategy. Twenty-eight proteins were found to be differentially expressed following B10 MSC transplantation in adult male Wistar rats, as assessed using isobaric tagging for relative and absolute protein quantification (iTRAQ). Subsequent bioinformatic analysis revealed that these proteins were mainly associated with energy metabolism, glutamate excitotoxicity, oxidative stress, and brain structural and functional plasticity. Immunohistochemical staining revealed decreased expression of EAAT1 in the phosphate-buffered saline group as opposed to normal levels in the B10 transplantation group. Furthermore, ATP levels were also significantly higher in the B10 transplantation group, thus supporting the iTRAQ results. Our results suggest that the therapeutic effects of B10 transplantation might arise from the modulation of the acute ischemic cascade via multiple molecular pathways. Thus, our findings provide valuable clues to elucidate the mechanisms underlying the therapeutic effects of MSC transplantation in ischemic stroke.


Assuntos
AVC Isquêmico/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/metabolismo , Modelos Animais de Doenças , AVC Isquêmico/fisiopatologia , Masculino , Proteômica/métodos , Ratos , Ratos Wistar , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/fisiopatologia
20.
Sci Total Environ ; 732: 138410, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32417549

RESUMO

Combining a popular flood disaster dataset with climate data and satellite land cover data from China, this paper estimates how forests mitigate the frequency of flooding, resulting in two major findings. First, we confirm that an increase in forest area mitigates the possibility of flood occurrence even after controlling for socioeconomic and meteorological variables and time-invariant individual effects. Second, broadleaf trees and mixed-tree forests have a flood mitigation effect, whereas coniferous trees do not; these results are robust against alternative model specifications. This paper newly corroborates the concept of ecosystem-based disaster risk reduction. While there is an emerging consensus that ecosystems can mitigate natural disasters, there is limited evidence on how ecosystems mitigate disasters. To the best of the authors' knowledge, this study is the first to show that the type of forest is critical for mitigating floods in a rigorous econometric way (survival analysis) spanning numerous areas of interest.

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