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1.
Neurosci Bull ; 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31435837

RESUMO

With the shifting role of placebos, there is a need to develop animal models of placebo analgesia and elucidate the mechanisms underlying the effect. In the present study, male Sprague-Dawley rats with chronic inflammatory pain caused by complete Freund's adjuvant (CFA) underwent a series of conditioning procedures, in which morphine was associated with different cues, but they failed to induce placebo analgesia. Then, conditioning with the conditioned place preference apparatus successfully induced analgesic expectancy and placebo analgesia in naïve rats but only induced analgesic expectancy and no analgesic effect in CFA rats. Subsequently, we found enhanced c-fos expression in the nucleus accumbens and reduced expression in the anterior cingulate cortex in naïve rats while c-fos expression in the anterior cingulate cortex in CFA rats was not altered. In summary, the behavioral conditioning model demonstrated the difficulty of establishing a placebo analgesia model in rats with a pathological condition.

2.
J Cell Mol Med ; 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31424159

RESUMO

Idiopathic dilated cardiomyopathy (IDCM), characterized by ventricular dilation and impaired systolic function, is a primary cardiomyopathy resulting in heart failure. During heart contraction, the Z-line is responsible for transmitting force between sarcomeres and is also a hot spot for muscle cell signalling. Mutations in Z-line proteins have been linked to cardiomyopathies in both humans and mice. Actinin-associated LIM protein (ALP) and enigma homolog protein (ENH), encoded by PDLIM3 and PDLIM5, are components of the muscle cytoskeleton and localize to the Z-line. A PDLIM3 or PDLIM5 deficiency in mice leads to dilated cardiomyopathy. Since PDLIM3 and PDLIM5 are candidate IDCM susceptibility genes, the current study aims to investigate whether polymorphisms within PDLIM3 and PDLIM5 could be correlated with IDCM. We designed a case-control study, and exons of the PDLIM3 and PDLIM5 were amplified by polymerase chain reactions in 111 IDCM patients and 137 healthy controls. We found that five synonymous polymorphisms had statistical distribution differences between IDCM patients and controls, including rs4861669, rs4862543, c.731 + 131 T > G, c.1789-3 C > T and rs7690296, according to genotype and allele distribution. Haplotype G-C-C-C and A-T-C-T (rs2306705, rs10866276, rs12644280 and rs4635850 synthesized) were regarded as risk factors for IDCM patients when compared with carriers of other haplotypes (all P < .05). Furthermore, IDCM patients with two novel polymorphisms (c.731 + 131 T > G and c.1789-3 C > T) had lower systolic blood pressure. In conclusion, these five synonymous polymorphisms might constitute a genetic background that increases the risk of the development of IDCM in the Chinese Han population.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31393786

RESUMO

In recent years, accumulating evidence has demonstrated the role of long non-coding RNAs (lncRNAs) in pathophysiological processes underlying gallbladder cancer. A microarray analysis identified that highly expressed lncRNA FOXD2-AS1 is associated with gallbladder cancer, and predicted its binding to the MutL homologue 1 (MLH1) promoter. Hence, we aimed to characterize the functional relevance of lncRNA FOXD2-AS1 in gallbladder cancer and the possible mechanisms associated with methylation of MLH1 in this study. Initially, FOXD2-AS1 was found to be highly expressed, while MLH1 was poorly expressed in gallbladder cancer cells. Of note, it was discovered that FOXD2-AS1 could promote MLH1 methylation by recruiting DNMT1. Moreover, in order to define the contributory role of FOXD2-AS1 in the progression of gallbladder cancer and to identify the interaction between FOXD2-AS1 and methylation of MLH1 promoter, the expression of MLH1, Ki67, and PCNA, as well as cell proliferation, migration, invasion, and apoptosis in gallbladder cancer was evaluated after over-expressing FOXD2-AS1 or silencing MLH1. Silencing FOXD2-AS1 or over-expression of MLH1 reduced the protein levels of Ki67 and PCNA, inhibited cell proliferation, invasion, migration, and facilitated cell apoptosis in gallbladder cancer, thus ultimately hindering the progression of gallbladder cancer, which was also validated in vivo. This study provides evidence demonstrating that silencing of FOXD2-AS1 suppressed the progression of gallbladder cancer via up-regulation of MLH1 by inhibiting MLH1 promoter methylation. Thus, FOXD2-AS1 knockdown may be a potential candidate for the treatment of gallbladder cancer.

4.
Theranostics ; 9(13): 3853-3865, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281518

RESUMO

N6-Methyladenosine (m6A) is the most prevalent internal modification in mammalian mRNAs. Although m6A is important in many biological processes, its roles in the placenta are unclear. Methods: Levels of global mRNA m6A methylation and ALKBH5 expression in recurrent miscarriage (RM) patients were determined using quantitative reverse transcription-PCR (qRT-PCR), m6A RNA methylation quantification, and immunohistochemical methods. Using ALKBH5 overexpression and knockdown methods, we determined the role of ALKBH5 in trophoblast invasion at the maternal interface through trophoblasts and an extravillous explant culture experiments. Furthermore, the regulation of CYR61 by ALKBH5 was explored by RNA-sequencing coupled with methylated RNA immunoprecipitation. Results: We found that the level of global mRNA m6A methylation was significantly decreased in placental villous tissue from RM patients, while ALKBH5 expression was specifically unregulated. Furthermore, we demonstrated that ALKBH5 knockdown in human trophoblast promoted trophoblast invasion. Conversely, overexpression of ALKBH5 inhibited cell invasion. ALKBH5 knockdown promoted trophoblast invasion in villous explant culture experiments, while overexpression of ALKBH5 repressed these effects. Furthermore, we clarified that ALKBH5 inhibited trophoblast invasion by regulating CYR61 mRNA stability, and this RNA regulation is m6A dependent. Mechanistic analyses showed that decreased ALKBH5 in trophoblast increased the half-life of CYR61 mRNA and promoted steady-state CYR61 mRNA expression levels. Conclusions: We elucidated the functional roles of ALKBH5 and mRNA m6A methylation in trophoblast and identified a novel RNA regulatory mechanism, providing a basis for further exploration of broad RNA epigenetic regulatory patterns in RM diseases.

5.
ACS Appl Mater Interfaces ; 11(28): 24984-24998, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31264830

RESUMO

The aim of this study was to design a click-crosslinked hyaluronic acid (HA) (Cx-HA) depot via a click crosslinking reaction between tetrazine-modified HA and trans-cyclooctene-modified HA for direct intra-articular injection into joints affected by rheumatoid arthritis (RA). The Cx-HA depot had significantly more hydrogel-like features and a longer in vivo residence time than the HA depot. Methotrexate (MTX)-loaded Cx-HA (MTX-Cx-HA)-easily prepared as an injectable formulation-quickly formed an MTX-Cx-HA depot that persisted at the injection site for an extended period. In vivo MTX biodistribution in MTX-Cx-HA depots showed that a high concentration of MTX persisted at the intra-articular injection site for an extended period, with little distribution of MTX to normal tissues. In contrast, direct intra-articular injection of MTX alone or MTX-HA resulted in rapid clearance from the injection site. After intra-articular injection of MTX-Cx-HA into rats with RA, we noted the most significant RA reversal, measured by an articular index score, increased cartilage thickness, extensive generation of chondrocytes and glycosaminoglycan deposits, extensive new bone formation in the RA region, and suppression of tumor necrosis factor-α or interleukin-6 expression. Therefore, MTX-Cx-HA injected intra-articularly persists at the joint site in therapeutic MTX concentrations for an extended period, thus increasing the duration of RA treatment, resulting in an improved relief of RA.

6.
J Mol Med (Berl) ; 97(9): 1359-1373, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31312859

RESUMO

NR4A1 (NUR77) is an orphan nuclear receptor that has been implicated in both cell survival and apoptosis. However, the role of NUR77 in trophoblast function during early placenta development has not been fully elucidated. In this study, we showed that NUR77 expression was significantly lower in the villi of the recurrent miscarriage (RM) group compared to that in the healthy controls (HCs) group. We used immunohistochemistry and found that NUR77 was highly expressed in human placental villi during early pregnancy, especially in syncytiotrophoblast (STB), and was expressed at a much lower level in STB from the RM group than in those from HC group. Western blotting data further confirmed that NUR77 was highly expressed in primary human term placental STB and the FSK-induced BeWo cell line. Moreover, antibody array screening and ELISA revealed that NUR77 promoted significant placental growth factor (PGF) expression during trophoblast fusion. Ectopic overexpression and knockdown experiments demonstrated that PGF was a novel downstream target of NUR77, and serum PGF expression correlated positively with trophoblast NUR77 mRNA levels in HCs and RM patients. Importantly, bioinformatics analysis identified two NUR77 binding sites in the PGF promoter region, and chromatin immunoprecipitation (ChIP) coupled with Western blotting analysis further verified that NUR77 bound directly to the PGF promoter region and promoted PGF expression. Furthermore, in a BeWo/HTR-8 co-culture system, FSK-induced BeWo-secreted PGF promoted HTR-8 cell migration and invasion, and an anti-PGF antibody reversed this effect. Collectively, these results indicated that NUR77 may play a key role in regulating trophoblast invasion at early pregnancy. KEY MESSAGES: NUR77 expression was significantly decreased in the syncytiotrophoblast of the recurrent miscarriage group compared to that in the healthy control group. NUR77 promoted PGF expression during trophoblast fusion. ChIP and western blotting experiments verified that NUR77 bound directly to the PGF promoter region and activated PGF expression in trophoblast. Trophoblast-derived PGF promoted HTR-8 cell migration and invasion in a cell co-culture system.

7.
BMC Genomics ; 20(1): 474, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182021

RESUMO

BACKGROUND: Extracellular vesicles (EVs) are small membrane vesicles secreted by the cells that mediate intercellular transfer of molecules and contribute to transduction of various signals. Viral infection and action of pro-inflammatory cytokines has been shown to alter molecular composition of EV content. Transfer of antiviral proteins by EVs is thought to contribute to the development of inflammation and antiviral state. Altered incorporation of selected host RNAs into EVs in response to infection has also been demonstrated for several viruses, but not for WNV. Considering the medical significance of flaviviruses and the importance of deeper knowledge about the mechanisms of flavivirus-host interactions we assessed the ability of West Nile virus (WNV) and type I interferon (IFN), the main cytokine regulating antiviral response to WNV, to alter the composition of EV RNA cargo. RESULTS: We employed next generation sequencing to perform transcriptome-wide profiling of RNA cargo in EVs produced by cells infected with WNV or exposed to IFN-alpha. RNA profile of EVs secreted by uninfected cells was also determined and used as a reference. We found that WNV infection significantly changed the levels of certain host microRNAs (miRNAs), small noncoding RNAs (sncRNAs) and mRNAs incorporated into EVs. Treatment with IFN-alpha also altered miRNA and mRNA profiles in EV but had less profound effect on sncRNAs. Functional classification of RNAs differentially incorporated into EVs upon infection and in response to IFN-alpha treatment demonstrated association of enriched in EVs mRNAs and miRNAs with viral processes and pro-inflammatory pathways. Further analysis revealed that WNV infection and IFN-alpha treatment changed the levels of common and unique mRNAs and miRNAs in EVs and that IFN-dependent and IFN-independent processes are involved in regulation of RNA sorting into EVs during infection. CONCLUSIONS: WNV infection and IFN-alpha treatment alter the spectrum and the levels of mRNAs, miRNAs and sncRNAs in EVs. Differentially incorporated mRNAs and miRNAs in EVs produced in response to WNV infection and to IFN-alpha treatment are associated with viral processes and host response to infection. WNV infection affects composition of RNA cargo in EVs via IFN-dependent and IFN-independent mechanisms.

8.
Chemistry ; 25(40): 9485-9490, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31001873

RESUMO

A novel synthesis of indanes and dihydronaphtalenes based on the intramolecular insertion into C(sp3 )-H bonds of gold(I) carbenes generated by retro-Buchner reaction (decarbenation) has been developed. Deuterium-labeling and kinetic isotope effect experiments, DFT calculations, and generation of the proposed carbene intermediate from a well-characterized gold(I) carbenoid support the involvement of a three-center concerted mechanism for the C(sp3 )-H functionalization process.

9.
Arthritis Rheumatol ; 71(7): 1174-1184, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30816640

RESUMO

OBJECTIVE: Clinical trial results have shown that, in glucocorticoid-treated patients, treatment with denosumab 60 mg subcutaneously once every 6 months (Q6M) increased spine and hip bone mineral density (BMD) at month 12 significantly more than treatment with risedronate 5 mg orally once daily (QD). The present analysis was performed to compare efficacy and characterize safety through month 24. METHODS: This phase III study enrolled men and women ≥18 years old who had received ≥7.5 mg daily prednisone or equivalent for <3 months (glucocorticoid-initiating) or for ≥3 months (glucocorticoid-continuing) before screening. All patients <50 years old had a history of osteoporotic fracture. Glucocorticoid-continuing patients ≥50 years old had T scores of -2.0 or less (or -1.0 or less with fracture history). Patients were randomized (1:1) to receive denosumab 60 mg subcutaneously Q6M or risedronate 5 mg orally QD for 24 months, with daily calcium and vitamin D. RESULTS: Of 795 patients, 590 (74.2%) completed the study (in the glucocorticoid-initiating group, 109 of 145 patients treated with denosumab and 117 of 145 patients treated with risedronate; in the glucocorticoid-continuing group, 186 of 253 patients treated with denosumab and 178 of 252 patients treated with risedronate). Denosumab was superior to risedronate in increasing lumbar spine and total hip BMD at all time points assessed, among glucocorticoid-initiating patients (24-month lumbar spine: BMD increase of 6.2% versus 1.7%, respectively [P < 0.001]; 24-month total hip: BMD increase of 3.1% versus 0.0% [P < 0.001]) and among glucocorticoid-continuing patients (24-month lumbar spine: BMD increase of 6.4% versus 3.2% [P < 0.001]; 24-month total hip: BMD increase of 2.9% versus 0.5% [P < 0.001]). Adverse events, serious adverse events (including infections), and fractures were similar between treatment groups. CONCLUSION: Denosumab was superior to risedronate in terms of increases in spine and hip BMD through month 24, and the safety profile was similar between treatment groups. Denosumab may offer a new osteoporosis treatment option for glucocorticoid-treated patients.

10.
Trends Microbiol ; 27(5): 381-383, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30826180

RESUMO

After the discovery that Zika virus (ZIKV) could cause microcephaly and other birth defects, we have scrambled to understand how. Now, spreading along with the virus is misinformation that a ZIKV mutation is responsible for microcephaly. Putting too much onus on a single mutation could enhance a crisis in India.

11.
Nat Microbiol ; 4(5): 876-887, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30886357

RESUMO

Arboviruses cycle between, and replicate in, both invertebrate and vertebrate hosts, which for Zika virus (ZIKV) involves Aedes mosquitoes and primates1. The viral determinants required for replication in such obligate hosts are under strong purifying selection during natural virus evolution, making it challenging to resolve which determinants are optimal for viral fitness in each host. Herein we describe a deep mutational scanning (DMS) strategy2-5 whereby a viral cDNA library was constructed containing all codon substitutions in the C-terminal 204 amino acids of ZIKV envelope protein (E). The cDNA library was transfected into C6/36 (Aedes) and Vero (primate) cells, with subsequent deep sequencing and computational analyses of recovered viruses showing that substitutions K316Q and S461G, or Q350L and T397S, conferred substantial replicative advantages in mosquito and primate cells, respectively. A 316Q/461G virus was constructed and shown to be replication-defective in mammalian cells due to severely compromised virus particle formation and secretion. The 316Q/461G virus was also highly attenuated in human brain organoids, and illustrated utility as a vaccine in mice. This approach can thus imitate evolutionary selection in a matter of days and identify amino acids key to the regulation of virus replication in specific host environments.


Assuntos
Análise Mutacional de DNA/métodos , Tropismo Viral , Infecção por Zika virus/virologia , Zika virus/fisiologia , Aedes/virologia , Animais , Evolução Biológica , Cercopithecus aethiops , Feminino , Especificidade de Hospedeiro , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Mosquitos Vetores/virologia , Mutação , Seleção Genética , Células Vero , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Replicação Viral , Zika virus/química , Zika virus/genética
12.
Nanoscale ; 11(12): 5158-5162, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30865748

RESUMO

Three pyrene-based spirocyclic aromatic hydrocarbons (Py-SAHs) were prepared to clarify the roles of molecular segments in regulating the morphologies and photophysical properties of organic microcrystals. Due to the different supramolecular steric hindrance (SSH) effect between bulky groups and pyrene rings, distinct nanocrystal morphologies with unique photoluminescence properties were realized.

13.
J Infect Dis ; 219(12): 2015-2025, 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-30715407

RESUMO

Rocio virus (ROCV) is a highly neuropathogenic mosquito-transmitted flavivirus responsible for an unprecedented outbreak of human encephalitis during 1975-1976 in Sao Paulo State, Brazil. Previous studies have shown an increased number of inflammatory macrophages in the central nervous system (CNS) of ROCV-infected mice, implying a role for macrophages in the pathogenesis of ROCV. Here, we show that ROCV infection results in increased expression of CCL2 in the blood and in infiltration of macrophages into the brain. Moreover, we show, using CCR2 knockout mice, that CCR2 expression is essential for macrophage infiltration in the brain during ROCV infection and that the lack of CCR2 results in increased disease severity and mortality. Thus, our findings show the protective role of CCR2-mediated infiltration of macrophages in the brain during ROCV infection.

14.
J Clin Endocrinol Metab ; 104(6): 2443-2452, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30759221

RESUMO

CONTEXT: Antiresorptive therapy has been associated with osteonecrosis of the jaw (ONJ), an infrequent but potentially serious adverse event. OBJECTIVE: To assess information on invasive oral procedures and events (OPEs)-dental implants, tooth extraction, natural tooth loss, scaling/root planing, and jaw surgery-during the 7-year Fracture REduction Evaluation of Denosumab in Osteoporosis every 6 Months (FREEDOM) Extension study and to present details of positively adjudicated ONJ cases. DESIGN: Randomized, double-blind, placebo-controlled, 3-year trial (FREEDOM) followed by 7 years of open-label denosumab (FREEDOM Extension). At Extension Year 3, women were asked to record their history of invasive OPEs since the start of the Extension to Year 2.5 and oral events in the prior 6 months. The questionnaire was then administered every 6 months until the end of the Extension. SETTING: Multicenter, multinational clinical trial. PATIENTS: Postmenopausal women with osteoporosis. INTERVENTIONS: Subcutaneous denosumab 60 mg or placebo every 6 months for 3 years, then 7 years of open-label denosumab. MAIN OUTCOME MEASURES: Self-reports of OPEs and adjudicated cases of ONJ. RESULTS: Of respondents, 45.1% reported at least one invasive OPE. The exposure-adjusted ONJ rate in FREEDOM Extension was 5.2 per 10,000 person-years. ONJ incidence was higher in those reporting an OPE (0.68%) than not (0.05%). CONCLUSIONS: Although invasive OPEs were common in these denosumab-treated women and were associated with an increased ONJ incidence, the overall rate of ONJ was low, and all cases with complete follow-up resolved with treatment.

15.
BMC Surg ; 19(1): 16, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30717712

RESUMO

BACKGROUND: To evaluate the perioperative and long-term results of intrahepatic bile duct exploration lithotomy (IHBDIL) combined with hepatectomy for patients with complicated bilateral primary hepatolithiasis. METHODS: A study was conducted involving 56 patients with complicated bilateral primary hepatolithiasis who underwent IHBDIL combined with hepatectomy at our hospital from January 2006 to December 2014. The perioperative and long-term outcomes that were retrospectively analysed included the stone clearance rate, operative morbidity and mortality, and stone recurrence rate. Patients with a preoperative diagnosis of cholangiocarcinoma were excluded. RESULTS: In all 56 patients, hepatic duct stones were located in the bilateral IHBD. The surgical method was IHBDIL combined with hepatectomy. Postoperative complications occurred in 15 patients (26.8%), 14 patients responded to conservative management, and there was 1 case of postoperative mortality because of hepatic failure. The overall initial success rate of stone clearance was 85.7%, and the final clearance rate was 92.9% following postoperative choledochoscopic lithotripsy. The stone recurrence rate was 13.5%, and the occurrence of postoperative cholangitis was 10.9% during the follow-up period. CONCLUSION: IHBDIL combined with hepatectomy is a safe, effective, and promising treatment for patients with complicated bilateral primary hepatolithiasis. The perioperative and long-term outcomes are satisfactory for complicated bilateral primary hepatolithiasis.


Assuntos
Ductos Biliares Intra-Hepáticos/cirurgia , Hepatectomia/métodos , Litíase/cirurgia , Hepatopatias/cirurgia , Adulto , Idoso , Procedimentos Cirúrgicos do Sistema Biliar , Feminino , Humanos , Laparoscopia/métodos , Hepatopatias/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
16.
DNA Repair (Amst) ; 74: 51-62, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30630676

RESUMO

Increasing evidence indicates that DNA damage and p53 activation play major roles in the pathological process of motor neuron death in amyotrophic lateral sclerosis (ALS). Human SpeedyA1 (Spy1), a member of the Speedy/Ringo family, enhances cell proliferation and promotes tumorigenesis. Further studies have demonstrated that Spy1 promotes cell survival and inhibits DNA damage-induced apoptosis. We showed that the Spy1 expression levels were substantially decreased in ALS motor neurons compared with wild-type controls both in vivo and in vitro by qRT-PCR, western blotting, and Immunoassay tests. In addition, we established that over-expression of human SOD1 mutant G93A led to a decreased expression of Spy1. Furthermore, DNA damage response was activated in SOD1G93A-transfected cells (mSOD1 cells). Moreover, decreased Spy1 expression reduced cell viability and further activated the DNA damage response in mSOD1 cells. In contrast, increased Spy1 expression improved cell viability and inhibited the DNA damage response in mSOD1 cells. These results suggest that Spy1 plays a protective role in ALS motor neurons. Importantly, these findings provide a novel direction for therapeutic options for patients with ALS as well as for trial designs, such as investigating the role of oncogenic proteins in ALS.


Assuntos
Esclerose Amiotrófica Lateral/patologia , Proteínas de Ciclo Celular/metabolismo , Dano ao DNA/genética , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Mutação , Superóxido Dismutase-1/genética , Animais , Proteínas de Ciclo Celular/deficiência , Proteínas de Ciclo Celular/genética , Linhagem Celular , Sobrevivência Celular , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos
17.
Mol Neurobiol ; 56(8): 5586-5607, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30652267

RESUMO

Protein kinase A (PKA) is a ser/thr kinase that is critical for maintaining essential neuronal functions including mitochondrial homeostasis, bioenergetics, neuronal development, and neurotransmission. The endogenous pool of PKA is targeted to the mitochondrion by forming a complex with the mitochondrial scaffold A-kinase anchoring protein 121 (AKAP121). Enhanced PKA signaling via AKAP121 leads to PKA-mediated phosphorylation of the fission modulator Drp1, leading to enhanced mitochondrial networks and thereby blocking apoptosis against different toxic insults. In this study, we show for the first time that AKAP121/PKA confers neuroprotection in an in vitro model of oxidative stress induced by exposure to excess glutamate. Unexpectedly, treating mouse hippocampal progenitor neuronal HT22 cells with an acute dose or chronic exposure of glutamate robustly elevates PKA signaling, a beneficial compensatory response that is phenocopied in HT22 cells conditioned to thrive in the presence of excess glutamate but not in parental HT22 cells. Secondly, redirecting the endogenous pool of PKA by transiently transfecting AKAP121 or transfecting a constitutively active mutant of PKA targeted to the mitochondrion (OMM-PKA) or of an isoform of AKAP121 that lacks the KH and Tudor domains (S-AKAP84) are sufficient to significantly block cell death induced by glutamate toxicity but not in an oxygen deprivation/reperfusion model. Conversely, transient transfection of HT22 neuronal cells with a PKA-binding-deficient mutant of AKAP121 is unable to protect against oxidative stress induced by glutamate toxicity suggesting that the catalytic activity of PKA is required for AKAP121's protective effects. Mechanistically, AKAP121 promotes neuroprotection by enhancing PKA-mediated phosphorylation of Drp1 to increase mitochondrial fusion, elevates ATP levels, and elicits an increase in the levels of antioxidants GSH and superoxide dismutase 2 leading to a reduction in the level of mitochondrial superoxide. Overall, our data supports AKAP121/PKA as a new molecular target that confers neuroprotection against glutamate toxicity by phosphorylating Drp1, to stabilize mitochondrial networks and mitochondrial function and to elicit antioxidant responses.

18.
J Colloid Interface Sci ; 539: 468-480, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30611042

RESUMO

Defects in bone are some of the most difficult injuries to treat. Biomimetic scaffolds represent a promising approach for successful bone tissue regeneration. In this study, a three-dimensional (3D) scaffold with osteo-inductive functionality was designed and assayed both in-vitro and in-vivo. Bone formation peptide-1 (BFP1), an osteo-promoting specific peptide, was covalently bound to a 3D printed polycaprolactone (PCL) scaffold using polydopamine (DOPA). The amount of BFP1 immobilized on the surface was found to increase depending on the BFP1 concentration of the loading solution. To observe the biological effects of the 3D scaffolds, human tonsil-derived mesenchymal stem cells (hTMSCs) were isolated. The cells were cultured on the scaffolds and observed to rapidly differentiate into osteoblast-like cells with osteo-promoting capabilities. The scaffolds were implanted in a rabbit calvarial defect model for 8 weeks and successfully stimulated both vessel and bone regeneration. Osteo-promoting 3D scaffolds may provide a safer and more efficient approach for bone repair and remodelling in regenerative medicine.


Assuntos
Proteína Morfogenética Óssea 7/química , Proteína Morfogenética Óssea 7/farmacologia , Regeneração Óssea/efeitos dos fármacos , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Impressão Tridimensional , Tecidos Suporte/química , Animais , Proteína Morfogenética Óssea 7/síntese química , Células Cultivadas , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Fragmentos de Peptídeos/síntese química , Coelhos
19.
J Cancer Res Ther ; 14(Supplement): S948-S956, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30539828

RESUMO

Objective: Sorafenib, an oral vascular endothelial growth factor receptor tyrosine-kinase inhibitor, has become a cornerstone in the treatment of various malignancies. However, concerns have arisen regarding the risk of hemorrhage with sorafenib use. Nevertheless, the contribution of sorafenib to hemorrhage and the underlying risk factors remains unclear. Materials and Methods: We performed a meta-analysis to determine the incidence and risk of hemorrhage associated with sorafenib treatment. Multiple databases were searched to identify relevant studies. The analysis included randomized controlled trials (RCTs) that directly compared cancer patients treated with or without sorafenib. Statistical analyses were conducted to determine the overall incidence, relative risks (RRs), and 95% confidence intervals (CIs) using fixed- or random-effect models. Results: Ten RCTs involving 4720 patients were included in the analysis. Overall, the incidence rates of all- and high-grade hemorrhage in patients receiving sorafenib were 9.89% (95% CI: 8.73-11.18%) and 2.86% (95% CI: 2.25-3.63%), respectively. Sorafenib treatment increased the risk of all-grade hemorrhage in patients compared to control treatment (RR: 1.99; 95% CI: 1.59-2.49; P < 0.00001), but did not increase the incidence of high-grade hemorrhage (RR: 1.42; 95% CI: 0.95-2.12; P = 0.09). Subgroup analysis showed no significant increase in the risk of hemorrhage between patients with various malignancies or concurrent treatment. No evidence of publication bias was observed. Conclusion: In patients with malignancy, sorafenib treatment combined with standard treatment significantly increases the risk of low-grade hemorrhagic events.


Assuntos
Antineoplásicos/efeitos adversos , Hemorragia/epidemiologia , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/efeitos adversos , Sorafenibe/efeitos adversos , Hemorragia/induzido quimicamente , Humanos , Incidência , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Resultado do Tratamento
20.
Viruses ; 10(10)2018 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-30282919

RESUMO

The recent emergence of Zika virus (ZIKV) in Brazil was associated with an increased number of fetal brain infections that resulted in a spectrum of congenital neurological complications known as congenital Zika syndrome (CZS). Herein, we generated de novo from sequence data an early Asian lineage ZIKV isolate (ZIKV-MY; Malaysia, 1966) not associated with microcephaly and compared the in vitro replication kinetics and fetal brain infection in interferon α/ß receptor 1 knockout (IFNAR1-/-) dams of this isolate and of a Brazilian isolate (ZIKV-Natal; Natal, 2015) unequivocally associated with microcephaly. The replication efficiencies of ZIKV-MY and ZIKV-Natal in A549 and Vero cells were similar, while ZIKV-MY replicated more efficiently in wild-type (WT) and IFNAR-/- mouse embryonic fibroblasts. Viremias in IFNAR1-/- dams were similar after infection with ZIKV-MY or ZIKV-Natal, and importantly, infection of fetal brains was also not significantly different. Thus, fetal brain infection does not appear to be a unique feature of Brazilian ZIKV isolates.

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