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1.
Exp Gerontol ; 183: 112322, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37929293

RESUMO

BACKGROUND: Severe sarcopenia may result in severe disability. Early diagnosis is currently the key to enhancing the treatment of sarcopenia, and there is an urgent need for a highly sensitive and dependable tool to evaluate the course of early sarcopenia in clinical practice. This study aims to investigate longitudinally the early diagnosability of magnetic resonance imaging (MRI)-based fat infiltration and blood flow perfusion technology in sarcopenia progression. METHODS: 48 Sprague-Dawley rats were randomly assigned into six groups that were based on different periods of dexamethasone (DEX) injection (0, 2, 4, 6, 8, 10 days). Multimodal MRI was scanned to assess muscle mass. Grip strength and swimming exhaustion time of rats were measured to assess muscle strength and function. Immunofluorescence staining for CD31 was employed to assess skeletal muscle capillary formation, and western blot was used to detect vascular endothelial growth factor-A (VEGF-A) and muscle ring finger-1 (MuRF-1) protein expression. Subsequently, we analyzed the correlation between imaging and histopathologic parameters. A receiver operating characteristic (ROC) analysis was conducted to assess the effectiveness of quantitative MRI parameters for discriminating diagnosis in both pre- and post-modeling of DEX-induced sarcopenic rats. RESULTS: Significant differences were found in PDFF, R2* and T2 values on day 2 of DEX-induction compared to the control group, occurring prior to the MRI-CSA values and limb grip strength on day 6 of induction and swimming exhaustion time on day 8 of induction. There is a strong correlation between MRI-CSA with HE-CSA values (r = 0.67; p < 0.001), oil red O (ORO) area with PDFF (r = 0.67; p < 0.001), microvascular density (MVD) (r = -0.79; p < 0.001) and VEGF-A (r = -0.73; p < 0.001) with R2*, MuRF-1 with MRI-CSA (r = -0.82; p < 0.001). The AUC of PDFF, R2*, and T2 values used for modeling evaluation are 0.81, 0.93, and 0.98, respectively. CONCLUSION: Imaging parameters PDFF, R2*, and T2 can be used to sensitively evaluate early pathological changes in sarcopenia. The successful construction of a sarcopenia rat model can be assessed when PDFF exceeds 1.25, R2* exceeds 53.85, and T2 exceeds 33.88.


Assuntos
Sarcopenia , Ratos , Animais , Sarcopenia/diagnóstico por imagem , Sarcopenia/patologia , Fator A de Crescimento do Endotélio Vascular , Músculo Quadríceps/diagnóstico por imagem , Músculo Quadríceps/patologia , Ratos Sprague-Dawley , Imageamento por Ressonância Magnética/métodos , Perfusão , Diagnóstico Precoce
2.
Exp Gerontol ; 172: 112053, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36509297

RESUMO

Tumor necrosis factor (TNF)-α is a proinflammatory cytokine involved in the pathogenesis of sarcopenia, but its short half-life and inconsistent reproducibility limit the potential of TNF-α to be an ideal sarcopenia biomarker. Anti-TNF-α, a natural consequent autoantibody to TNF-α, is an indicator of relatively prolonged TNF-α exposure, has more stable concentrations than TNF-α and should be a better alternative as a biomarker of sarcopenia. Data from 484 participants from the I-Lan Longitudinal Aging Study were used for this study, and sarcopenia was defined by the Asian Working Group for Sarcopenia 2019 consensus. Plasma levels of anti-TNF-α were determined by a sandwich ELISA approach, and levels of TNF-α were determined by an immunoassay. Compared to nonsarcopenic participants, 43 sarcopenic participants had higher levels of anti-TNF-α (0.73 ± 0.19 vs. 0.79 ± 0.25 OD, p = 0.045). Plasma levels of anti-TNF-α were positively correlated with TNF-α (r = 0.24, p < 0.001), and plasma levels of anti-TNF-α were positively correlated with adiposity (r = 0.16, p < 0.001) and negatively correlated with lean body mass (r = -0.14, p = 0.003). Individuals with increasing levels of anti-TNF-α had higher odds of being sarcopenic (OR 5.4, 95 % CI: 1.1-25.8, p = 0.035), and these associations were stronger among women and younger adults. An association between TNF-α and sarcopenia was noted only in middle-aged adults (OR 6.2, 95 % CI: 1.8-21.7, p = 0.004). Plasma anti-TNF-α levels were positively correlated with TNF-α and were significantly associated with sarcopenia. Anti-TNF-α may be a more appropriate biomarker than TNF-α for sarcopenia, but further investigations are needed to confirm its roles in sarcopenia diagnosis and treatment response evaluation.


Assuntos
Sarcopenia , Feminino , Humanos , Pessoa de Meia-Idade , Envelhecimento , Biomarcadores , Necrose/complicações , Reprodutibilidade dos Testes , Inibidores do Fator de Necrose Tumoral , Fator de Necrose Tumoral alfa/imunologia , Autoanticorpos
3.
Biomedicines ; 9(9)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34572415

RESUMO

Cisd2 (CDGSH iron sulfur domain 2) is a pro-longevity gene that extends the lifespan and health span of mice, ameliorates age-associated structural damage and limits functional decline in multiple tissues. Non-alcoholic fatty liver disease (NAFLD), which plays an important role in age-related liver disorders, is the most common liver disease worldwide. However, no medicines that can be used to specifically and effectively treat NAFLD are currently approved for this disease. Our aim was to provide pathological and molecular evidence to show that Cisd2 protects the liver from age-related dysregulation of lipid metabolism and protein homeostasis. This study makes four major discoveries. Firstly, a persistently high level of Cisd2 protects the liver from age-related fat accumulation. Secondly, proteomics analysis revealed that Cisd2 ameliorates age-related dysregulation of lipid metabolism, including lipid biosynthesis and ß-oxidation, in mitochondria and peroxisomes. Thirdly, Cisd2 attenuates aging-associated oxidative modifications of proteins. Finally, Cisd2 regulates intracellular protein homeostasis by maintaining the functionality of molecular chaperones and protein synthesis machinery. Our proteomics findings highlight Cisd2 as a novel molecular target for the development of therapies targeting fatty liver diseases, and these new therapies are likely to help prevent subsequent malignant progression to cirrhosis and hepatocellular carcinoma.

4.
Biochim Biophys Acta Mol Cell Res ; 1868(4): 118954, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33422617

RESUMO

CDGSH Iron Sulfur Domain 2 (CISD2) is the causative gene for the disease Wolfram syndrome 2 (WFS2; MIM 604928), which is an autosomal recessive disorder showing metabolic and neurodegenerative manifestations. CISD2 protein can be localized on the endoplasmic reticulum (ER), outer mitochondrial membrane (OMM) and mitochondria-associated membrane (MAM). CISD2 plays a crucial role in the regulation of cytosolic Ca2+ homeostasis, ER integrity and mitochondrial function. Here we summarize the most updated publications and discuss the central role of CISD2 in maintaining cellular homeostasis. This review mainly focuses on the following topics. Firstly, that CISD2 has been recognized as a prolongevity gene and the level of CISD2 is a key determinant of lifespan and healthspan. In mice, Cisd2 deficiency shortens lifespan and accelerates aging. Conversely, a persistently high level of Cisd2 promotes longevity. Intriguingly, exercise stimulates Cisd2 gene expression and thus, the beneficial effects offered by exercise may be partly related to Cisd2 activation. Secondly, that Cisd2 is down-regulated in a variety of tissues and organs during natural aging. Three potential mechanisms that may mediate the age-dependent decrease of Cisd2, via regulating at different levels of gene expression, are discussed. Thirdly, the relationship between CISD2 and cell survival, as well as the potential mechanisms underlying the cell death control, are discussed. Finally we discuss that, in cancers, CISD2 may functions as a double-edged sword, either suppressing or promoting cancer development. This review highlights the importance of the CISD2 in aging and age-related diseases and identifies the urgent need for the translation of available genetic evidence into pharmaceutic interventions in order to alleviate age-related disorders and extend a healthy lifespan in humans.


Assuntos
Envelhecimento/genética , Proteínas Relacionadas à Autofagia/metabolismo , Cálcio/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Envelhecimento/metabolismo , Animais , Proteínas Relacionadas à Autofagia/genética , Retículo Endoplasmático/metabolismo , Homeostase , Humanos , Longevidade , Proteínas de Membrana/genética , Camundongos , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas do Tecido Nervoso/genética
5.
Biochem Biophys Res Commun ; 533(3): 467-473, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-32977949

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by 2019 novel coronavirus (2019-nCoV) has been a crisis of global health, whereas the effective vaccines against 2019-nCoV are still under development. Alternatively, utilization of old drugs or available medicine that can suppress the viral activity or replication may provide an urgent solution to suppress the rapid spread of 2019-nCoV. Andrographolide is a highly abundant natural product of the medicinal plant, Andrographis paniculata, which has been clinically used for inflammatory diseases and anti-viral therapy. We herein demonstrate that both andrographolide and its fluorescent derivative, the nitrobenzoxadiazole-conjugated andrographolide (Andro- NBD), suppressed the main protease (Mpro) activities of 2019-nCoV and severe acute respiratory syndrome coronavirus (SARS-CoV). Moreover, Andro-NBD was shown to covalently link its fluorescence to these proteases. Further mass spectrometry (MS) analysis suggests that andrographolide formed a covalent bond with the active site Cys145 of either 2019-nCoV Mpro or SARS-CoV Mpro. Consistently, molecular modeling analysis supported the docking of andrographolide within the catalytic pockets of both viral Mpros. Considering that andrographolide is used in clinical practice with acceptable safety and its diverse pharmacological activities that could be beneficial for attenuating COVID-19 symptoms, extensive investigation of andrographolide on the suppression of 2019-nCoV as well as its application in COVID-19 therapy is suggested.


Assuntos
Cisteína Endopeptidases/metabolismo , Diterpenos/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo , Betacoronavirus/enzimologia , Domínio Catalítico , Proteases 3C de Coronavírus , Cisteína Endopeptidases/química , Diterpenos/química , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Simulação de Acoplamento Molecular , Conformação Proteica , Multimerização Proteica , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/enzimologia , SARS-CoV-2 , Proteínas não Estruturais Virais/química
6.
Quant Imaging Med Surg ; 10(1): 106-115, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31956534

RESUMO

BACKGROUND: Our study aimed to investigate the feasibility of functional magnetic resonance imaging [blood oxygen level-dependent (BOLD) imaging and T2 mapping] in monitoring the activation of lumbar paraspinal muscles before and after exercise. METHODS: The ethics committee of the First Affiliated Hospital of Kunming Medical University approved our study. Both BOLD and T2 mapping of paraspinal muscles were performed in 50 healthy, young volunteers before and after upper-body extension exercises. The movement tasks included upper body flexion and extension using a simple Roman chair. Cross-sectional area (CSA), R2*, and T2 values were measured in various lower-back anatomical regions. The SPSS22.0 statistical software was used to analyze all the data. RESULTS: Post-exercise CSA and T2 values were higher than those recorded in the pre-exercise session for the three lower-back muscles that were evaluated (iliocostalis, longissimus, and multifidus) (P<0.01). However, R2* values of these muscles were significantly lower after exercise (P<0.01). A significant difference in the R2*, CSA, and T2 values of the iliocostalis occurred between males and females (P<0.05). No statistically significant differences were evident for R2*, CSA, and T2 of the lower-back muscles between L3 and L4 levels, or between the left and right sides. The total CSA of the iliocostalis was higher than that of the multifidus and longissimus (P<0.05). CONCLUSIONS: BOLD and T2 mapping are feasible non-invasive indirect assessments of lumbar paraspinal muscle activation before and after exercise.

7.
Biochem Pharmacol ; 163: 308-320, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30822403

RESUMO

Chronic myelogenous leukemia (CML) is clinically treated with imatinib, which inhibits the kinase activity of the Bcr-Abl oncoprotein. However, imatinib resistance remains a common clinical issue. Andrographolide, the major compound of the medicinal plant Andrographis paniculata, was reported to exhibit anticancer activity. In this study, we explored the therapeutic potential of andrographolide and its derivative, NCTU-322, against both imatinib-sensitive and imatinib-resistant human CML cell lines. Both andrographolide and NCTU-322 downregulated the Bcr-Abl oncoprotein in imatinib-resistant CML cells through an Hsp90-dependent mechanism similar to that observed in imatinib-sensitive CML cells. In addition, NCTU-322 had stronger effects than andrographolide on downregulation of Bcr-Abl oncoprotein, induction of Hsp90 cleavage and cytotoxicity of CML cells. Notably, andrographolide and NCTU-322 could induce differentiation, mitotic arrest and apoptosis of both imatinib-sensitive and imatinib-resistant CML cells. Finally, the anticancer activity of NCTU-322 against imatinib-resistant CML cells was demonstrated in vivo. In summary, our data demonstrated that andrographolide and NCTU-322 inhibit Bcr-abl function via a mechanism different from that of imatinib, and they induced multiple anticancer effects in both imatinib-sensitive and resistant CML cells. Our findings demonstrate that andrographolide and NCTU-322 are potential therapeutic agents again CML.


Assuntos
Antineoplásicos/farmacologia , Diterpenos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes abl/fisiologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/química , Resistencia a Medicamentos Antineoplásicos , Genes abl/genética , Humanos , Mesilato de Imatinib/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Estrutura Molecular
8.
Mol Cell Oncol ; 5(3): e1441627, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30250893

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease and is the major risk factor leading to hepatocellular carcinoma (HCC). Cisd2 haploinsufficiency in mice causes NAFLD by disrupting Ca2+ homeostasis, indicating that CISD2 is a molecular target for the treatment of NAFLD and the prevention of HCC.

9.
Cell Rep ; 21(8): 2198-2211, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29166610

RESUMO

CISD2 is located within the chromosome 4q region frequently deleted in hepatocellular carcinoma (HCC). Mice with Cisd2 heterozygous deficiency develop a phenotype similar to the clinical manifestation of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Cisd2 haploinsufficiency causes a low incidence (20%) of spontaneous HCC and promotes HBV-associated and DEN-induced HCC; conversely, 2-fold overexpression of Cisd2 suppresses HCC in these models. Mechanistically, Cisd2 interacts with Serca2b and mediates its Ca2+ pump activity via modulation of Serca2b oxidative modification, which regulates ER Ca2+ uptake and maintains intracellular Ca2+ homeostasis in the hepatocyte. CISD2 haploinsufficiency disrupts calcium homeostasis, causing ER stress and subsequent NAFLD and NASH. Hemizygous deletion and decreased expression of CISD2 are detectable in a substantial fraction of human HCC specimens. These findings substantiate CISD2 as a haploinsufficient tumor suppressor and highlights Cisd2 as a drug target when developing therapies to treat NAFLD/NASH and prevent HCC.


Assuntos
Cálcio/metabolismo , Carcinoma Hepatocelular/patologia , Proteínas de Transporte/metabolismo , Haploinsuficiência/genética , Neoplasias Hepáticas/patologia , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Proteínas Relacionadas à Autofagia , Carcinoma Hepatocelular/metabolismo , Proteínas de Transporte/genética , Homeostase/fisiologia , Humanos , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia
10.
Sheng Li Xue Bao ; 68(2): 148-56, 2016 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-27108901

RESUMO

The aim of the present study was to investigate the effects of minocycline on cognitive functions in neonatal rat after hypoxia exposure and the underlying mechanism. A model of hypoxic brain damage (HBD) was developed by exposing postnatal 1 day (P1) rats to systemic hypoxia. The rats were intraperitoneally injected with normal saline (Hy group) or minocycline (Hy + M group) 2 h after hypoxia exposure. Some other P1 rats that were not subjected to systemic hypoxia were used as normal control (NG group). The Y-maze test was used to evaluate learning and memory ability on postnatal day 30. Inflammatory mediators (Iba-1, IL-1ß, TNF-α and TGF-ß1), glutamate transporters (EAAT1 and EAAT2), total Tau and phosphorylated Tau (phosphorylation sites: Tyr18, Thr205, Thr231, Ser396 and Ser404) protein expressions in the hippocampus were detected by Western blot 7 d after hypoxic exposure. The results showed that hypoxia induced learning and memory impairments of the neonatal rats, and minocycline administration could reverse the effects of hypoxia. The protein expression levels of Iba-1, IL-1ß, TNF-α, EAAT2 and Tau phosphorylated at T231 were increased, but the total Tau expression was decreased in the hippocampus of the rats from Hy group 7 d after hypoxia exposure. In the hypoxia-treated rats, minocycline down-regulated Iba-1, IL-1ß, TNF-α and EAAT2 protein expressions significantly, but did not affect total Tau and phosphorylated Tau protein expressions. Our results suggest that minocycline can prevent cognitive deficits of rats with hypoxia exposure, and the underlying mechanism may involve the inhibition of neuroinflammation and dysfunctional glutamate transporters but not the regulation of the Tau hyperphosphorylation.


Assuntos
Cognição , Hipóxia , Sistema X-AG de Transporte de Aminoácidos , Animais , Animais Recém-Nascidos , Transtornos Cognitivos , Modelos Animais de Doenças , Glutamatos , Hipocampo , Inflamação , Aprendizagem , Memória , Transtornos da Memória , Minociclina , Fosforilação , Ratos , Fator de Crescimento Transformador beta1 , Fator de Necrose Tumoral alfa , Proteínas tau
11.
Anal Bioanal Chem ; 404(8): 2387-96, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22941070

RESUMO

The serine hydrolase family consists of more than 200 members and is one of the largest enzyme families in the human genome. Although up to 50 % of this family remains unannotated, there are increasing evidences that activities of certain serine hydrolases are associated with diseases like cancer neoplasia, invasiveness, etc. By now, several activity-based chemical probes have been developed and are applied to profile the global activity of serine hydrolases in diverse proteomes. In this study, two fluorophosphonate (FP)-based chemical probes were synthesized. Further examination of their abilities to label and pull down serine hydrolases was conducted. In addition, the poly-3-hydroxybutyrate depolymerase (PhaZ) from Bacillus thuringiensis was demonstrated as an appropriate standard serine hydrolase, which can be applied to measure the labeling ability and pull-down efficiency of FP-based probes. Furthermore, mass spectrometry (MS) was used to identify the serine residue that covalently bonded to the active probes. Finally, these FP-based probes were shown capable of establishing the serine hydrolase profiles in diverse mouse tissues; the serine hydrolases pulled down from mouse liver organ were further identified by MS. In summary, our study provides an adequate method to evaluate the reactivity of FP-based probes targeting serine hydrolases.


Assuntos
Bacillus thuringiensis/enzimologia , Técnicas de Química Analítica , Flúor/análise , Fígado/enzimologia , Sondas Moleculares/análise , Organofosfonatos/análise , Serina Proteases/metabolismo , Animais , Western Blotting , Hidrolases de Éster Carboxílico/metabolismo , Eletroforese em Gel de Poliacrilamida , Flúor/química , Espectrometria de Massas , Camundongos , Sondas Moleculares/síntese química , Sondas Moleculares/química , Organofosfonatos/síntese química , Organofosfonatos/química
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