RESUMO
Osteoporosis results from overactivation of osteoclasts. There are currently few drug options for treatment of this disease. Since the successful development of allosteric inhibitors, phosphatases have become attractive therapeutic targets. Protein phosphatase 1, regulatory subunit 15 A (PPP1R15A), is a stress-responsive protein, which promotes the UPR (unfolded protein response) and restores protein homeostasis. In this study we investigated the role of PPP1R15A in osteoporosis and osteoclastogenesis. Ovariectomy (OVX)-induced osteoporosis mouse model was established, osteoporosis was evaluated in the left femurs using micro-CT. RANKL-stimulated osteoclastogenesis was used as in vitro models. We showed that PPP1R15A expression was markedly increased in BMMs derived from OVX mice and during RANKL-induced osteoclastogenesis in vitro. Knockdown of PPP1R15A or application of Sephin1 (a PPP1R15A allosteric inhibitor in a phase II clinical trial) significantly inhibited osteoclastogenesis in vitro. Sephin1 (0.78, 3.125 and 12.5 µM) dose-dependently mitigated the changes in NF-κB, MAPK, and c-FOS and the subsequent nuclear factor of activated T cells 1 (NFATc1) translocation in RANKL-stimulated BMMs. Both Sephin1 and PPP1R15A knockdown increased the phosphorylated form of eukaryotic initiation factor 2α (eIF2α); knockdown of eIF2α reduced the inhibitory effects of Sephin1 on NFATc1-luc transcription and osteoclast formation. Furthermore, Sephin1 or PPP1R15A knockdown suppressed osteoclastogenesis in CD14+ monocytes from osteoporosis patients. In OVX mice, injection of Sephin1 (4, 8 mg/kg, i.p.) every two days for 6 weeks significantly inhibited bone loss, and restored bone destruction and decreased TRAP-positive cells. This study has identified PPP1R15A as a novel target for osteoclast differentiation, and genetic inhibition or allosteric inhibitors of PPP1R15A, such as Sephin1, can be used to treat osteoporosis. This study revealed that PPP1R15A expression was increased in osteoporosis in both human and mice. Inhibition of PPP1R15A by specific knockdown or an allosteric inhibitor Sephin1 mitigated murine osteoclast formation in vitro and attenuated ovariectomy-induced osteoporosis in vivo. PPP1R15A inhibition also suppressed pathogenic osteoclastogenesis in CD14+ monocytes from osteoporosis patients. These results identify PPP1R15A as a novel regulator of osteoclastogenesis and a valuable therapeutic target for osteoporosis.
Assuntos
Guanabenzo , Osteoporose , Animais , Feminino , Humanos , Camundongos , Diferenciação Celular , Guanabenzo/análogos & derivados , Guanabenzo/uso terapêutico , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Osteoclastos , Osteogênese , Osteoporose/tratamento farmacológico , Ovariectomia , Proteína Fosfatase 1/metabolismo , Proteína Fosfatase 1/farmacologia , Ligante RANK/metabolismoRESUMO
BACKGROUND: Doxorubicin (DOX) is a first-line chemotherapeutic drug for various malignancies that causes cardiotoxicity. Plant-derived exosome-like nanovesicles (P-ELNs) are growing as novel therapeutic agents. Here, we investigated the protective effects in DOX cardiotoxicity of ELNs from Momordica charantia L. (MC-ELNs), a medicinal plant with antioxidant activity. RESULTS: We isolated MC-ELNs using ultracentrifugation and characterized them with canonical mammalian extracellular vesicles features. In vivo studies proved that MC-ELNs ameliorated DOX cardiotoxicity with enhanced cardiac function and myocardial structure. In vitro assays revealed that MC-ELNs promoted cell survival, diminished reactive oxygen species, and protected mitochondrial integrity in DOX-treated H9c2 cells. We found that DOX treatment decreased the protein level of p62 through ubiquitin-dependent degradation pathway in H9c2 and NRVM cells. However, MC-ELNs suppressed DOX-induced p62 ubiquitination degradation, and the recovered p62 bound with Keap1 promoting Nrf2 nuclear translocation and the expressions of downstream gene HO-1. Furthermore, both the knockdown of Nrf2 and the inhibition of p62-Keap1 interaction abrogated the cardioprotective effect of MC-ELNs. CONCLUSIONS: Our findings demonstrated the therapeutic beneficials of MC-ELNs via increasing p62 protein stability, shedding light on preventive approaches for DOX cardiotoxicity.
Assuntos
Cardiotoxicidade , Doxorrubicina , Exossomos , Momordica charantia , Fator 2 Relacionado a NF-E2 , Animais , Cardiotoxicidade/prevenção & controle , Cardiotoxicidade/metabolismo , Momordica charantia/química , Exossomos/metabolismo , Ratos , Fator 2 Relacionado a NF-E2/metabolismo , Linhagem Celular , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Ratos Sprague-Dawley , Proteína Sequestossoma-1/metabolismoRESUMO
Although green light (GL) is located in the middle of the visible light spectrum and regulates a series of plant developmental processes, the mechanism by which it regulates seedling development is largely unknown. In this study, we demonstrated that GL promotes atypical photomorphogenesis in Arabidopsis thaliana via the dual regulations of phytochrome B (phyB) and phyA. Although the Pr-to-Pfr conversion rates of phyB and phyA under GL were lower than those under red light (RL) in a fluence rate-dependent and time-dependent manner, long-term treatment with GL induced high Pfr/Pr ratios of phyB and phyA. Moreover, GL induced the formation of numerous small phyB photobodies in the nucleus, resulting in atypical photomorphogenesis, with smaller cotyledon opening angles and longer hypocotyls in seedlings compared to RL. The abundance of phyA significantly decreased after short- and long-term GL treatments. We determined that four major PHYTOCHROME-INTERACTING FACTORs (PIFs: PIF1, PIF3, PIF4, and PIF5) act downstream of phyB in GL-mediated cotyledon opening. In addition, GL plays opposite roles in regulating different PIFs. For example, under continuous GL, the protein levels of all PIFs decreased, whereas the transcript levels of PIF4 and PIF5 strongly increased compared with dark treatment. Taken together, our work provides a detailed molecular framework for understanding the role of the antagonistic regulations of phyB and phyA in GL-mediated atypical photomorphogenesis.
RESUMO
BACKGROUND: The +294T/C polymorphism in the peroxisome proliferator-activated receptor delta (PPARD) gene is associated with hyperlipidemia in several younger populations, but results are still inconsistence across ethnic groups and its possible impact on the lipid profiles of long-lived individuals remains unexploited. Here, we aimed to evaluate the possible correlation between PPARD +294T/C and serum lipid levels in a long-lived population in Bama, a region known for longevity situated in Guangxi, China. METHODS: Genotyping of PPARD +294T/C polymorphism was conducted in 505 long-lived inhabitants (aged 90 and above, long-lived group, LG) and 468 healthy controls (aged 60-75, non-long-lived group, non-LG) recruited from Bama area. RESULTS: No difference in allelic and genotypic frequencies was found between the two groups (P>0.05). However, C-allele and C-genotype (TC and CC) were significantly more frequent in the females of non-LG than were LG after sex stratification. CC carriers exhibited higher LDL-C level in LG (P<0.05) but lower TC, TG and LDL-C in non-LG (P<0.05 for each) than TT carriers; C allele carriers (TC/CC) in LG exhibited higher TC, TG, and LDL-C levels as compared with the same genotype and the same lipid parameter in non-LG (P<0.05 for each). LDL-C in LG was correlated with genotypes while TC, TG, and LDL-C in non-LG were correlated with genotypes (P<0.05-0.001). CONCLUSION: Our results suggest that there were different impact patterns of PPARD +294T/C polymorphism on lipid profiles between long-lived cohort and average population in Bama area and this may be one of the genetic bases of its longevity.
Assuntos
Lipídeos/sangue , Longevidade/genética , PPAR delta/genética , Polimorfismo de Nucleotídeo Único/genética , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/genética , Estudos de Casos e Controles , China/epidemiologia , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangueRESUMO
BACKGROUND: Variants in the Methylenetetrahydrofolate reductase (MTHFR) gene may result in a lowered catalytic activity and associate with subsequent elevated serum homocysteine (Hcy) concentration, abnormal DNA synthesis and methylation, cardiovascular risk, and unhealthy aging. Several investigations on the relationship of MTHFR C677T polymorphism with serum lipid profile and longevity have been conducted in some populations, but the findings remain mixed. Herein, we sought to look at the association between MTHFR C677T and lipid profile in a longevous cohort in Bama, a well-known home of longevity in China. METHODS: Genotyping of MTHFR C677T was undertaken in 516 long-lived inhabitants (aged 90 and older, long-lived group, LG) and 493 healthy controls (aged 60-75, non-long-lived group, non-LG) recruited from Bama area. Correlation between MTHFR genotypes and lipids was then evaluated. RESULTS: T allele and TT genotype were significantly more prevalent in LG (P=0.001 and 0.002, respectively), especially in females, than in non-LG. No difference in the tested lipid measures among MTHFR C677T genotypes was observed in LG, non-LG and total population (P>0.05 for all). However, female but not male T carriers exhibited higher TC and LDL-C levels than did T noncarriers in the total population and in LG after stratification by sex (P<0.05 for each). These differences did not however remain through further subdivision by hyperlipidemia and normolipidemia. CONCLUSION: The higher prevalence of MTHFR 677 T genotypes and its modest unfavorable impact on lipids in Bama long-lived individuals may imply an existence of other protective genotypes which require further determination.
Assuntos
Longevidade/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , China , Feminino , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/genética , Metabolismo dos Lipídeos/genética , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Objectives: To investigate the causal relationships between pneumoconiosis and rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and gout. Methods: The random-effects inverse variance weighted (IVW) approach was utilized to explore the causal effects of the instrumental variables (IVs). Sensitivity analyses using the MR-Egger and weighted median (WM) methods were did to investigate horizontal pleiotropy. A leave-one-out analysis was used to avoid the bias resulting from single-nucleotide polymorphisms (SNPs). Results: There was no causal association between pneumoconiosis and SLE, RA or gout in the European population [OR = 1.01, 95% CI: 0.94-1.10, p = 0.74; OR = 1.00, 95% CI: 0.999-1.000, p = 0.50; OR = 1.00, 95% CI: 1.000-1.001, p = 0.55]. Causal relationships were also not found in pneumoconiosis due to asbestos and other mineral fibers and SLE, RA and gout [OR = 1.01, 95% CI: 0.96-1.07, p = 0.66; OR = 1.00, 95% CI: 1.00-1.00, p = 0.68; OR = 1.00, 95% CI: 1.00-1.00, p = 0.20]. Conclusion: Our study suggests that pneumoconiosis may have no causal relationship with the three inflammatory immune diseases.
Assuntos
Gota , Doenças do Sistema Imunitário , Lúpus Eritematoso Sistêmico , Pneumoconiose , Humanos , Análise da Randomização Mendeliana , Pneumoconiose/epidemiologiaRESUMO
OBJECTIVE: To investigate a case of delayed hemolytic transfusion reaction (DHTR), and find the reason and coping strategies to prevent similar incidents in the future. METHODS: Relative antibody identification was carried out, suitable erythrocytes was screened, and relevant indicators after transfusion were evaluated. Medical record and laboratory report of the patient were reviewed, the cause was analyzed, and corresponding treatment was carried out. RESULTS: The patient suffered from DHTR caused by IgM anti-M antibody and low body temperature cardiopulmonary bypass. After anti-hemolytic treatment, the patient was gradually improved, the bilirubin gradually decreased, and finally cured and discharged. CONCLUSION: When the transfusion department finds any antibodies which have activity at room temperature but no respond at 37 â, they should communicate with clinical medical staff in time. Warm transfusion should be used during blood transfusion to prevent transfusion-related hemolytic reaction.
RESUMO
OBJECTIVE: To evaluate the efficacy and safety of different types of red blood cell (RBC) transfusion and hormone therapy in patients with autoimmune hemolytic anemia (AIHA). METHODS: The clinical data and serological characteristics of 40 patients with AIHA treated in our hospital from 2014 to 2018 were collected and analyzed retrospectively. The efficacy and safety of different type of RBC transfusion and hormone therapy were evaluated according to the principle of minimally incompatible RBC transfusion after cross-matching. RESULTS: Among 40 patients with AIHA, the female cases were more than the male cases, the cases of secondary AIHA was more than cases of primary AIHA, and the warm autoantibodies were in the majority. 11 cases of AIHA underwent 26 times minimally incompatible red blood cell transfusions. The total effective rate was 46.2%, the partial efficiency was 23.1%, and total inefficiency was 30.8%. Among them, the same type of non-washing red blood cell group showed efficiency of 42.1%, partial effective rate of 21.1%, and inefficiency of 36.8%; the same type of washed red blood cell group showed efficiency of 57.1%, partial effective rate of 28.6%, and inefficiency of 14.3%. the infusion effects was not significanly different between the two groups, and no hemolytic transfusion reaction occurred. In the hormone-treated group, the complete remission rate was 15.2%, the partial remission rate was 63.6%, and the ineffective rate was 21.2%. Among them, the side effects appeared in 2 patients after using hormones. CONCLUSION: When AIHA patients need blood transfusion, use the same type of non-washed red blood cells or homologous washed cells is relatively safe, and the difference in efficacy is not significant. The partial remission of patients received hormone therapy is much higher than that of red blood cell transfusion, but the side effects easily happen.