Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
1.
Nat Metab ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773347

RESUMO

Lipid droplet tethering with mitochondria for fatty acid oxidation is critical for tumor cells to counteract energy stress. However, the underlying mechanism remains unclear. Here, we demonstrate that glucose deprivation induces phosphorylation of the glycolytic enzyme phosphofructokinase, liver type (PFKL), reducing its activity and favoring its interaction with perilipin 2 (PLIN2). On lipid droplets, PFKL acts as a protein kinase and phosphorylates PLIN2 to promote the binding of PLIN2 to carnitine palmitoyltransferase 1A (CPT1A). This results in the tethering of lipid droplets and mitochondria and the recruitment of adipose triglyceride lipase to the lipid droplet-mitochondria tethering regions to engage lipid mobilization. Interfering with this cascade inhibits tumor cell proliferation, promotes apoptosis and blunts liver tumor growth in male mice. These results reveal that energy stress confers a moonlight function to PFKL as a protein kinase to tether lipid droplets with mitochondria and highlight the crucial role of PFKL in the integrated regulation of glycolysis, lipid metabolism and mitochondrial oxidation.

3.
Nat Chem Biol ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538923

RESUMO

Telomere dysfunction is intricately linked to the aging process and stands out as a prominent cancer hallmark. Here we demonstrate that telomerase activity is differentially regulated in cancer and normal cells depending on the expression status of fructose-1,6-bisphosphatase 1 (FBP1). In FBP1-expressing cells, FBP1 directly interacts with and dephosphorylates telomerase reverse transcriptase (TERT) at Ser227. Dephosphorylated TERT fails to translocate into the nucleus, leading to the inhibition of telomerase activity, reduction in telomere lengths, enhanced senescence and suppressed tumor cell proliferation and growth in mice. Lipid nanoparticle-mediated delivery of FBP1 mRNA inhibits liver tumor growth. Additionally, FBP1 expression levels inversely correlate with TERT pSer227 levels in renal and hepatocellular carcinoma specimens and with poor prognosis of the patients. These findings demonstrate that FBP1 governs cell immortality through its protein phosphatase activity and uncover a unique telomerase regulation in tumor cells attributed to the downregulation or deficiency of FBP1 expression.

4.
Sci Total Environ ; 924: 171631, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38467254

RESUMO

Soil acidification is an ongoing problem in intensively cultivated croplands due to inefficient and excessive nitrogen (N) fertilization. We collected high-resolution data comprising 19,969 topsoil (0-20 cm) samples from the Land Use and Coverage Area frame Survey (LUCAS) of the European commission in 2009 to assess the impact of N fertilization on buffering substances such as carbonates and base cations. We have only considered the impacts of mineral fertilizers from the total added N, and a N use efficiency of 60 %. Nitrogen fertilization adds annually 6.1 × 107 kmol H+ to European croplands, leading to annual loss of 6.1 × 109 kg CaCO3. Assuming similar acidification during the next 50 years, soil carbonates will be completely removed from 3.4 × 106 ha of European croplands. In carbonate-free soils, annual loss of 2.1 × 107 kmol of basic cations will lead to strong acidification of at least 2.6 million ha of European croplands within the next 50 years. Inorganic carbon and basic cation losses at such rapid scale tremendously drop the nutrient status and production potential of croplands. Soil liming to ameliorate acidity increases pH only temporarily and with additional financial and environmental costs. Only the direct loss of soil carbonate stocks and compensation of carbonate-related CO2 correspond to about 1.5 % of the proposed budget of the European commission for 2023. Thus, controlling and decreasing soil acidification is crucial to avoid degradation of agricultural soils, which can be done by adopting best management practices and increasing nutrient use efficiency. Regular screening or monitoring of carbonate and base cations contents, especially for soils, where the carbonate stocks are at critical levels, are urgently necessary.

5.
Am J Cancer Res ; 13(10): 4742-4754, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37970353

RESUMO

Rapidly growing tumors often encounter energy stress, such as glutamine deficiency. However, how normal and tumor cells differentially respond to glutamine deficiency remains largely unclear. Here, we demonstrate that glutamine deprivation activates PERK, which phosphorylates FBP1 at S170 and induces nuclear accumulation of FBP1. Nuclear FBP1 inhibits PPARα-mediated ß-oxidation gene transcription in normal lung epithelial cells. In contrast, highly expressed OGT in non-small cell lung cancer (NSCLC) cells promotes FBP1 O-GlcNAcylation, which abrogates FBP1 phosphorylation and enhances ß-oxidation gene transcription to support cell proliferation under glutamine deficiency. In addition, FBP1 pS170 is negatively correlated with OGT expression in human NSCLC specimens, and low expression of FBP1 pS170 is associated with poor prognosis in NSCLC patients. These findings highlight the differential regulation of FBP1 in normal and NSCLC cells under glutamine deprivation and underscore the potential to target nuclear FBP1 for NSCLC treatment.

6.
Int J Mol Sci ; 24(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36982956

RESUMO

Rheumatoid arthritis (RA) is an autoimmune polyarthritis in which synovial fibroblasts (SFs) play a major role in cartilage and bone destruction through tumor-like proliferation, migration, and invasion. Circular RNAs (circRNAs) have emerged as vital regulators for tumor progression. However, the regulatory role, clinical significance, and underlying mechanisms of circRNAs in RASF tumor-like growth and metastasis remain largely unknown. Differentially expressed circRNAs in synovium samples from patients with RA and patients with joint trauma were identified via RNA sequencing. Subsequently, in vitro and in vivo experiments were performed to investigate the functional roles of circCDKN2B-AS_006 in RASF proliferation, migration, and invasion. CircCDKN2B-AS_006 was upregulated in synovium samples from patients with RA and promoted the tumor-like proliferation, migration, and invasion of RASFs. Mechanistically, circCDKN2B-AS_006 was shown to regulate the expression of runt-related transcription factor 1 (RUNX1) by sponging miR-1258, influencing the Wnt/ß-catenin signaling pathway, and promoting the epithelial-to-mesenchymal transition (EMT) in RASFs. Moreover, in the collagen-induced arthritis (CIA) mouse model, intra-articular injection of lentivirus-shcircCDKN2B-AS_006 was capable of alleviating the severity of arthritis and inhibiting the aggressive behaviors of SFs. Furthermore, the correlation analysis results revealed that the circCDKN2B-AS_006/miR-1258/RUNX1 axis in the synovium was correlated with the clinical indicators of RA patients. CircCDKN2B-AS_006 promoted the proliferation, migration, and invasion of RASFs by modulating the miR-1258/RUNX1 axis.


Assuntos
Artrite Reumatoide , MicroRNAs , Neoplasias , Animais , Camundongos , RNA Circular/genética , RNA Circular/metabolismo , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Artrite Reumatoide/metabolismo , Membrana Sinovial/patologia , Neoplasias/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fibroblastos/metabolismo , Proliferação de Células/genética , Células Cultivadas
8.
Agric Food Secur ; 11(1): 59, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36540662

RESUMO

Background: Interest in local food has been growing, driven by increased attention from consumers, supporting policies, and interest in offering supply by local producers. Nonetheless, a definition of "local food" remains elusive, varying with purposes, geographies, and perceptions. This study quantifies online media mentioning local food in 2018-2021 using online and social media listening and analytics. In addition, a sub-search devoted to local food security and access was conducted due to a high proportion of mentions devoted to food security in the initial search. Variations in mentions and net sentiment quantified for individual US states are also presented. Results: The local food pantry sub-search arose after finding a large share of the general local food media was referencing local food access rather than production or other topics. The interest in local food access was more apparent during crises periods, such as the COVID-19 pandemic, during which even a larger portion of mentions are devoted to the local food pantry sub-search topic. Mentions quantified from the sub-search are mostly expressing concerns about worsened food insecurity during the pandemic and encouraging others to do things like donate food to local pantries. Conclusions: Online and social media can play an important role towards active communication in local communities on topics, such as food availability and access. In addition, online media can facilitate more efficient emergency management.

9.
Int Immunopharmacol ; 113(Pt A): 109328, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36279671

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovial hyperplasia and progressive joint destruction in the middle and late stages. Notably, activated rheumatoid arthritis synovial fibroblasts (RASFs) exhibit tumor-like features, including an increased proliferation rate that largely contributes to pannus formation and joint destruction. Our previous studies have demonstrated that acid-sensing ion channel 1a (ASIC1a) was highly expressed in RASFs, and acidic microenvironment of synovial fluid in patients with RA can activate ASIC1a to promote synovial inflammation, leading to the progression of RA. However, the role and possible mechanism of ASIC1a in RASF proliferation remains unclear. The present study aimed to investigate the effect of ASIC1a activation upon acidosis on RASF proliferation and its molecular mechanism in vivo and in vitro. The results of in vitro experiments showed that activation of ASIC1a upon acidosis promoted the proliferation of RASFs, which could be attenuated by the specific ASIC1a inhibitor Psalmotoxin-1 (PcTx-1) or specific siRNA for ASIC1a. Mechanistically, Wnt/ß-catenin/c-Myc signaling pathway was involved in ASIC1a-induced RASF proliferation. The results of in vivo experiments indicated that intra-articular injection of PcTx-1 reduced synovial hyperplasia and ameliorated cartilage degradation in rats with adjuvant arthritis (AA). Collectively, these results suggest that activation of ASIC1a upon acidosis promotes RASF proliferation, and the mechanism may be related to Wnt/ß-catenin/c-Myc pathway.


Assuntos
Canais Iônicos Sensíveis a Ácido , Acidose , Artrite Reumatoide , Animais , Ratos , Canais Iônicos Sensíveis a Ácido/genética , Canais Iônicos Sensíveis a Ácido/metabolismo , Acidose/metabolismo , Acidose/patologia , Artrite Reumatoide/genética , beta Catenina/metabolismo , Cateninas/metabolismo , Cateninas/farmacologia , Proliferação de Células , Células Cultivadas , Fibroblastos , Hiperplasia/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Membrana Sinovial/patologia , Via de Sinalização Wnt
10.
Front Oncol ; 12: 912881, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35978827

RESUMO

Hepatocellular carcinoma (HCC) is an inflammation-associated cancer. However, the lipid pro-inflammatory mediators have only been seldom investigated in HCC pathogenesis. Cylindromatosis (CYLD) attenuation is involved in hepatocarcinogenesis. Here, we aimed to evaluate the significance of hepatic lipid pro-inflammatory metabolites of arachidonate-affected CYLD expression via the 5-lipoxygenase (5-LO) pathway. Resection liver tissues from HCC patients or donors were evaluated for the correlation of 5-LO/cysteinyl leukotrienes (CysLTs) signaling to the expression of CYLD. The impact of functional components in 5-LO/CysLTs cascade on survival of HCC patients was subsequently assessed. Both livers from canines, a preponderant animal for cancer research, and genetic-modified human HCC cells treated with hepatocarcinogen aristolochic acid I (AAI) were further used to reveal the possible relevance between 5-LO pathway activation and CYLD suppression. Five-LO-activating protein (FLAP), an essential partner of 5-LO, was significantly overexpressed and was parallel to CYLD depression, CD34 neovascular localization, and high Ki-67 expression in the resection tissues from HCC patients. Importantly, high hepatic FLAP transcription markedly shortened the median survival time of HCC patients after surgical resection. In the livers of AAI-treated canines, FLAP overexpression was parallel to enhanced CysLTs contents and the simultaneous attenuation of CYLD. Moreover, knock-in FLAP significantly diminished the expression of CYLD in AAI-treated human HCC cells. In summary, the hepatic FLAP/CysLTs axis is a crucial suppressor of CYLD in HCC pathogenesis, which highlights a novel mechanism in hepatocarcinogenesis and progression. FLAP therefore can be explored for the early HCC detection and a target of anti-HCC therapy.

12.
Infect Drug Resist ; 15: 1821-1829, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35444432

RESUMO

Objective: Critical patients in intensive care unit (ICU) are highly susceptible to acquiring carbapenem-resistant Acinetobacter baumannii (CRAB) infection. To investigate the relationship between nosocomial infections and environmental health, we studied the distribution and homology of CRAB isolates from patients and environment and evaluated the effectiveness of infection control measures. Methods: In the 4-month study, we conducted a monthly CRAB screening of the ICU environment prior to disinfection in a Chinese teaching hospital. The ICU underwent routine disinfection procedures twice a day. We collected samples from the environment around the patients before disinfection. Clinical specimens from patients were also screened. The samples obtained were studied for phenotype and homology via antibiotic susceptibility testing, pulsed-field gel electrophoresis (PFGE), and whole-genome sequencing (WGS). Results: Ten specimens were sampled from ICU environments. Five were obtained in May 2020, and sputums from patient a in bed A at this time were cultured for CRAB isolates; in June 2020 another 5 environmental specimens were obtained from the same bed unit for CRAB, and sputums from patient b in bed A at this time were also cultured for CRAB isolates. Following intensive infection control measures, environmental sampling was negative in July and August. These 18 CRAB isolates all carried OXA-66 and OXA-23 genes and showed a similar resistance phenotype. WGS showed a close relationship among specimens from patients' sputum and their surroundings, but no homology between patients. Conclusion: The analysis of cgMLST and SNPs is more accurate for strain homology analysis. Our data confirm that CRAB isolates spread from patient to environment in ICU; however, contact isolation and disinfection measures are effective in avoiding transmission, highlighting the importance of continued education and surveillance of CRAB. WGS could provide rich information on antimicrobial resistance, which is of great value in scientific research and clinical diagnosis.

14.
Lab Invest ; 102(8): 859-871, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35292759

RESUMO

Nesfatin-1, a newly identified energy-regulating peptide, has been reported to possess antioxidant, anti-inflammatory, and antiapoptotic properties; however, to date, its effect on rheumatoid arthritis (RA) has not been previously explored in detail. We previously showed that activation of acid-sensing ion channel 1a (ASIC1a) by acidosis plays an important role in RA pathogenesis. Therefore, in this study, we evaluated the effects of nesfatin-1 on acidosis-stimulated chondrocyte injury in vitro and in vivo and examined the involvement of ASIC1a and the mechanism underlying the effects of nesfatin-1 on RA. Acid-stimulated articular chondrocytes were used to examine one of the several possible mechanisms underlying RA pathogenesis in vitro. The mRNA expression profile of acid-induced chondrocytes treated or not treated with nesfatin-1 was investigated by RNA sequencing. The effects of nesfatin-1 on oxidative stress, inflammation, and apoptosis in acid-induced chondrocytes were measured. The mechanistic effect of nesfatin-1 on ASIC1a expression and intracellular Ca2+ in acid-stimulated chondrocytes was studied. Rats with adjuvant-induced arthritis (AA) were used for in vivo analysis of RA pathophysiology. Cartilage degradation and ASIC1a expression in chondrocytes were detected in rats with AA after intraarticular nesfatin-1 injection. The in vitro experiments showed that nesfatin-1 decreased acidosis-induced cytotoxicity and elevation of intracellular Ca2+ levels in chondrocytes. Moreover, it attenuated acid-induced oxidative stress, inflammation, and apoptosis in chondrocytes. Nesfatin-1 decreased ASIC1a protein levels in acid-stimulated chondrocytes via the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) and nuclear factor kappa-B (NF-κB) signaling pathways. In vivo analysis showed that nesfatin-1 ameliorated cartilage degradation and decreased ASIC1a expression in the chondrocytes of rats with AA. Collectively, nesfatin-1 suppressed acidosis-induced oxidative stress, inflammation, and apoptosis in acid-stimulated chondrocytes and alleviated arthritis symptoms in rats with AA, and its mechanism may be related to its ability to decrease ASIC1a protein levels via the MAPK/ERK and NF-κB pathways.


Assuntos
Canais Iônicos Sensíveis a Ácido , Acidose , Artrite Experimental , Cartilagem Articular , Nucleobindinas , Canais Iônicos Sensíveis a Ácido/metabolismo , Acidose/metabolismo , Acidose/patologia , Animais , Artrite Experimental/metabolismo , Cartilagem Articular/metabolismo , Células Cultivadas , Condrócitos/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Inflamação/metabolismo , NF-kappa B/metabolismo , Nucleobindinas/metabolismo , Ratos , Ratos Sprague-Dawley
15.
Sci Total Environ ; 825: 154087, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35218836

RESUMO

The long-term stability of soil inorganic carbon (SIC) and its minimum contribution towards global C cycle has been challenged, as recent studies have showed rapid decreases in SIC stocks in intensive agricultural systems. However, the extent of SIC losses and its driving factors remains unclear. Here, we compared changes in SIC density (SICD) in Chinese croplands between the 1980s and 2010s. The SIC contents in 1980s were obtained from second national soil survey (n = 949) and published studies (n = 47). The SIC contents in 2010s were based on resampling of soil profiles from the same locations during 2019 and 2020 (n = 30), as well as data from published studies and national soil survey (n = 903). We found that Chinese croplands have lost 27-38% of SICD from the 0-40 cm soil layer and that the soil pH has decreased by 0.53 units over the past 30 years. These SIC losses increased with the ratio of precipitation (P) to potential evapotranspiration (PET) and most notably with nitrogen (N) fertilization. The SICD decreased greatly in humid and semiarid regions, and these losses were enhanced by high N fertilization rates; however, the SICD increased in very arid regions. This analysis demonstrates that the water balance and N fertilization are major drivers leading to dramatic losses of SICD in croplands and, consequently, to decreases in soil fertility and functions.


Assuntos
Carbono , Solo , Agricultura , Carbono/análise , China , Produtos Agrícolas , Nitrogênio/análise , Solo/química
17.
Oxid Med Cell Longev ; 2021: 2231680, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34873428

RESUMO

Radiation-induced oral mucositis is a major adverse event of radiotherapy. Severe oral mucositis may cause unwanted interruption in radiotherapy and reduce long-term survival in cancer patients receiving radiotherapy, but until now, there have been no effective options for preventing radiation-induced oral mucositis. Quercetin is a flavonoid that is widely found in food species and has anti-inflammatory, antioxidant, and anticancer activities. In this study, we investigated a new role of quercetin in preventing radiation-induced oral mucositis. Quercetin exerted preventive effects against radiation-induced oral mucositis induced by single-dose (25 Gy) ionizing radiation or fractionated ionizing radiation (8 Gy × 3) in C57BL/6 mice and maintained the proliferation ability of basal epithelial cells. Quercetin pretreatment alleviated reactive oxygen species generation, NF-κB pathway activation, and downstream proinflammatory cytokine production and reduced DNA double-strand breaks and cellular senescence induced by ionizing radiation. Quercetin also upregulated BMI-1 expression in oral epithelial cells and promoted ulcer repair. In addition, quercetin exerted similar radioprotective effects in irradiated primary cultured normal human keratinocytes, reduced reactive oxygen species generation and proinflammatory cytokine release, and promoted DNA double-strand break repair and wound healing by upregulating the expression of BMI-1, which is a polycomb group protein. Thus, quercetin can block multiple pathological processes of radiation-induced oral mucositis by targeting BMI-1 and may be a potential treatment option for preventing radiation-induced oral mucositis.


Assuntos
Complexo Repressor Polycomb 1/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Quercetina/farmacologia , Lesões Experimentais por Radiação/prevenção & controle , Estomatite/prevenção & controle , Animais , Antioxidantes/farmacologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Lesões Experimentais por Radiação/metabolismo , Distribuição Aleatória , Estomatite/etiologia , Estomatite/metabolismo , Regulação para Cima/efeitos dos fármacos
18.
BMC Med ; 19(1): 191, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34365975

RESUMO

BACKGROUND: Knowledge about the 1-year outcome of COVID-19 is limited. The aim of this study was to follow-up and evaluate lung abnormalities on serial computed tomography (CT) scans in patients with COVID-19 after hospital discharge. METHODS: A prospective cohort study of patients with COVID-19 from the First Affiliated Hospital, Zhejiang University School of Medicine was conducted, with assessments of chest CT during hospitalization and at 2 weeks, 1 month, 3 months, 6 months, and 1 year after hospital discharge. Risk factors of residual CT opacities and the influence of residual CT abnormalities on pulmonary functions at 1 year were also evaluated. RESULTS: A total of 41 patients were followed in this study. Gradual recovery after hospital discharge was confirmed by the serial CT scores. Around 47% of the patients showed residual aberration on pulmonary CT with a median CT score of 0 (interquartile range (IQR) of 0-2) at 1 year after discharge, with ground-glass opacity (GGO) with reticular pattern as the major radiologic pattern. Patients with residual radiological abnormalities were older (p = 0.01), with higher rate in current smokers (p = 0.04), higher rate in hypertensives (p = 0.05), lower SaO2 (p = 0.004), and higher prevalence of secondary bacterial infections during acute phase (p = 0.02). Multiple logistic regression analyses indicated that age was a risk factor associated with residual radiological abnormalities (OR 1.08, 95% CI 1.01-1.15, p = 0.02). Pulmonary functions of total lung capacity (p = 0.008) and residual volume (p < 0.001) were reduced in patients with residual CT abnormalities and were negatively correlated with CT scores. CONCLUSION: During 1-year follow-up after discharge, COVID-19 survivors showed continuous improvement on chest CT. However, residual lesions could still be observed and correlated with lung volume parameters. The risk of developing residual CT opacities increases with age.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Adulto , COVID-19/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , SARS-CoV-2 , Tomografia Computadorizada por Raios X
19.
Eur J Pharmacol ; 908: 174381, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34310912

RESUMO

Epidemiological data suggest that the incidence of rheumatoid arthritis (RA) increases in postmenopausal women, which may be related to estrogen deficiency. Tissue acidosis is a common symptom of RA. Acid-sensitive ion channel 1a (ASIC1a), a member of the extracellular H+-activated cation channel family, could be activated by changes in extracellular pH and plays a crucial role in the pathogenesis of RA. As the only cellular component in cartilage tissue, chondrocytes play an extremely important role in maintaining cartilage tissue homeostasis. The aim of this study was to investigate whether estrogen could protect acid-stimulated chondrocytes by regulating the expression of ASIC1a and explore the possible mechanism. The results showed that estrogen could protect against acid-induced chondrocyte injury by reducing ASIC1a protein expression. Moreover, lysosome inhibitor chloroquine (CQ) and autophagy inhibitor 3-methyladeniine (3-MA) could reverse the reduction of ASIC1a protein caused by estrogen, indicating that autophagy-lysosome pathway contributes to estrogen-induced degradation of ASIC1a protein. Furthermore, the down-regulation of ASIC1a expression by estrogen was attenuated by MPP, a specific inhibitor of estrogen-related receptor-alpha (Esrra), indicating that Esrra is involved in the process of estrogen regulating the expression of ASIC1a. Additionally, adenosine 5'-monophosphate (AMP)-activated protein kinase/unc-51-like kinase 1 (AMPK-ULK1) signaling pathway was activated by estrogen treatment, which was abrogated by Esrra-silencing, and AMPK-specific inhibitor Compound C pretreatment could reduce estrogen-induced downregulation of ASIC1a protein. Taken together, these results indicate that estrogen could promote autophagy-lysosome pathway-dependent ASIC1a protein degradation and protect against acidosis-induced cytotoxicity, the mechanisms of which might relate to Esrra-AMPK-ULK1 signaling pathway.


Assuntos
Condrócitos , Canais Iônicos Sensíveis a Ácido , Acidose , Animais , Cartilagem Articular , Humanos , Proteólise , Ratos
20.
Lab Invest ; 101(10): 1353-1362, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34282280

RESUMO

Synovial hyperplasia, a profound alteration in the structure of synovial tissue, is the basis for cumulative joint destruction in rheumatoid arthritis (RA). It is generally accepted that controlling synovial hyperplasia can delay the progression of RA. As one of the most intensively studied isoforms of acid-sensing ion channels (ASICs), ASIC1a contributes to various physiopathologic conditions, including RA, due to its unique property of being permeable to Ca2+. However, the role and the regulatory mechanisms of ASIC1a in synovial hyperplasia are poorly understood. Here, rats induced with adjuvant arthritis (AA) and human primary synovial fibroblasts were used in vivo and in vitro to investigate the role of ASIC1a in the proliferation of RA synovial fibroblasts (RASFs). The results show that the expression of ASIC1a was significantly increased in synovial tissues and RASFs obtained from patients with RA as well as in the synovium of rats with AA. Moreover, extracellular acidification improved the ability of RASFs colony formation and increased the expression of proliferation cell nuclear antigen (PCNA) and Ki67, which was abrogated by the specific ASIC1a inhibitor psalmotoxin-1 (PcTX-1) or ASIC1a-short hairpin RNA (ASIC1a-shRNA), suggesting that extracellular acidification promotes the proliferation of RASFs by activating ASIC1a. In addition, the activation of c-Raf and extracellular signal-regulated protein kinases (ERKs) signaling was blocked with PcTX-1 or ASIC1a-shRNA and the proliferation of RASFs was further inhibited by the ERK inhibitor (U0126), indicating that ERK/MAPK signaling contributes to the proliferation process of RASFs promoted by the activation of ASIC1a. These findings gave us an insight into the role of ASIC1a in the proliferation of RASFs, which may provide solid foundation for ASIC1a as a potential target in the treatment of RA.


Assuntos
Canais Iônicos Sensíveis a Ácido/metabolismo , Artrite Experimental/metabolismo , Proliferação de Células/fisiologia , Fibroblastos/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Animais , Células Cultivadas , Humanos , Ratos , Membrana Sinovial/química , Membrana Sinovial/citologia , Membrana Sinovial/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA