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A homozygous mutation of the DNAJC6 gene causes autosomal recessive familial type 19 of Parkinson's disease (PARK19). To test the hypothesis that PARK19 DNAJC6 mutations induce the neurodegeneration of dopaminergic cells by reducing the protein expression of functional DNAJC6 and causing DNAJC6 paucity, an in vitro PARK19 model was constructed by using shRNA-mediated gene silencing of endogenous DANJC6 in differentiated human SH-SY5Y dopaminergic neurons. shRNA targeting DNAJC6 induced the neurodegeneration of dopaminergic cells. DNAJC6 paucity reduced the level of cytosolic clathrin heavy chain and the number of lysosomes in dopaminergic neurons. A DNAJC6 paucity-induced reduction in the lysosomal number downregulated the protein level of lysosomal protease cathepsin D and impaired macroautophagy, resulting in the upregulation of pathologic α-synuclein or phospho-α-synucleinSer129 in the endoplasmic reticulum (ER) and mitochondria. The expression of α-synuclein shRNA or cathepsin D blocked the DNAJC6 deficiency-evoked degeneration of dopaminergic cells. An increase in ER α-synuclein or phospho-α-synucleinSer129 caused by DNAJC6 paucity activated ER stress, the unfolded protein response and ER stress-triggered apoptotic signaling. The lack of DNAJC6-induced upregulation of mitochondrial α-synuclein depolarized the mitochondrial membrane potential and elevated the mitochondrial level of superoxide. The DNAJC6 paucity-evoked ER stress-related apoptotic cascade, mitochondrial malfunction and oxidative stress induced the degeneration of dopaminergic neurons via activating mitochondrial pro-apoptotic signaling. In contrast with the neuroprotective function of WT DNAJC6, the PARK19 DNAJC6 mutants (Q789X or R927G) failed to attenuate the tunicamycin- or rotenone-induced upregulation of pathologic α-synuclein and stimulation of apoptotic signaling. Our data suggest that PARK19 mutation-induced DNAJC6 paucity causes the degeneration of dopaminergic neurons via downregulating protease cathepsin D and upregulating neurotoxic α-synuclein. Our results also indicate that PARK19 mutation (Q789X or R927G) impairs the DNAJC6-mediated neuroprotective function.
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Catepsina D , Neurônios Dopaminérgicos , Estresse do Retículo Endoplasmático , Proteínas de Choque Térmico HSP40 , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , alfa-Sinucleína/genética , Apoptose/genética , Catepsina D/metabolismo , Catepsina D/genética , Linhagem Celular Tumoral , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Regulação para Baixo , Proteínas de Choque Térmico HSP40/metabolismo , Proteínas de Choque Térmico HSP40/genética , Lisossomos/metabolismo , Mitocôndrias/metabolismo , Doença de Parkinson/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/patologia , Regulação para CimaRESUMO
Introduction: Chemotherapy and radiation therapy for breast cancer cause side effects, such as cardiovascular changes, which can be monitored with echocardiography. However, more convenient methods are always encouraged. Radial arterial waves that are used to detect cardiovascular changes can be used to assist in confirming cardiovascular changes. Aim: This retrospective study aimed to analyze the frequency and time domains of the radial artery pulse wave in patients with breast cancer to understand its effectiveness in identifying cardiovascular changes. Methods: Patients with breast cancer were screened from the pulse examination records in Changhua Christian Hospital and divided into the treatment and remission groups. After unlinking the data, the pulse data were analyzed for the breast cancer treatment and remission group, including the average value of the parameters of four consecutive pulse diagnosis records in four consecutive months to test the difference in pulse waves due to breast cancer treatment between the two groups. Additionally, the pulse wave stability of the two groups was compared using the coefficient of variation. Results and conclusion: The comparison of the pulse wave data between 19 patients in the treatment group and 40 patients in the remission group revealed 45 parameters in time and 50 in frequency domains. D3, ND3, NA1, and NT1 are the four parameters with significant differences (p < 0.05), which are all related to heart function, and mainly related to cardiac output and peripheral resistance, indicating that patients in the treatment period have poor heart function. No difference was found in the degree of data dispersion between the two groups. Cardiovascular side effects caused by breast cancer treatment can mainly be shown in the pulse wave time domain.
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BACKGROUND: Type 2 hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant disease and is associated with ALK1 gene mutations. Type 2 HHT patients primarily suffer from recurrent bleeding. There is currently no promising treatment. CASE SUMMARY: A 5-year-old Chinese patient (III23) was admitted to Zhongshan Hospital for recurrent melena occurring over 2 mo. She had been experiencing epistaxis for years and had been diagnosed with idiopathic pulmonary hypertension 4 mo before presentation. Abdominal computed tomography examination showed hepatic arteriovenous malformation. Gene testing revealed a c.1121G>A mutation on the ALK1 gene. According to the international diagnostic criteria, this patient was diagnosed with HHT. In addition, 8 more family members exhibited HHT symptoms to varying degrees. Gene testing in 5 family members (2 with HHT symptoms and 3 without HHT symptoms) revealed the ALK1 c.1121G>A mutation in the 2 family members with HHT symptoms. This missense mutation results in the substitution of arginine for glutamine at amino acid position 374 (R374Q) in the conserved functional kinase domain of ALK1. Biological studies revealed that this mutation decreased the kinase activity of ALK1 and impeded the phosphorylation of its substrate Smad1. Moreover, the R374Q mutant downregulated the protein level of collagen-1, a fibrogenic factor, indicating abnormal fiber generation during vascular formation. CONCLUSION: The R374Q mutant of ALK1 and its subsequent influence on fiber generation highly indicated its pathogenic role in this family with type 2 HHT. Detection of this gene mutation will facilitate early diagnosis of suspected type 2 HHT patients, and mechanistic studies will provide insights for future therapy.
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Objective: Ultrasound (US) detection acupuncture (UDA) is an innovative acupuncture technique that uses ultrasonography (USG) to detect the depth of the lung before performing acupuncture on the points around the chest to avoid puncturing the lungs. For acupuncturists to use UDA appropriately, it is crucial to have a good operating method to identify the pleura with USG. This study compared 2 US operating methods through active learning in a "flipped classroom" setting for acupuncture students. Materials and Methods: Students and interns were recruited to complete the UDA flipped classroom course and evaluate the operations of 2 US methods on either of 2 simulation models: (1) a single B-mode or (2) a combined M-mode + B-mode. Participants were interviewed and satisfaction surveys were administered to obtain feedback. Results: A total of 37 participants completed the course and evaluations. The combined mode had better measurement accuracy, acupuncture safety, and operating time (P < 0.05), and no pneumothoraxes occurred. Among both participant groups, the combined mode allowed the student group to learn quickly and the intern group to become more proficient. Both interviews and satisfaction surveys yielded positive feedback. Conclusions: Using a combined mode for UDA can improve its performance greatly. The combined mode is definitely helpful for learning and promotion of UDA.
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The reflex auriculo-cardiac (RAC), dynamic pulse reaction (Nogier reflex), or vascular autonomic signal was proposed by Nogier. It refers to the pulse changes that can occur in the radial artery immediately after auricular acupuncture is performed. RAC is helpful for the clinical practice of auricular acupuncture, but there is a lack of objective verification methods. Photoplethysmography (PPG) has been used to objectively calculate radial artery blood flow. This study used PPG via a smartphone to measure RAC induced by auricular acupuncture. Thirty subjects without major diseases were recruited to receive traditional needle and laser acupuncture. The Shen Men ear point and control points were stimulated for 20 s. PPG was continuously measured during the acupuncture. The PPG data were tested for differences with a paired t-test. The results showed that there were no statistical differences in the frequency and amplitude of PPG obtained before and after acupuncture, either with a traditional needle or laser acupuncture. However, interestingly, it was found that one patient with insomnia, one patient with viral respiratory symptoms, and two menstruating females exhibited changes in PPG within five seconds of needle placement. We hypothesized that RAC might be induced by auricular acupuncture and could be quantified by PPG, even among subjects suffering from mild diseases; however, auricular acupuncture might not induce a measurable RAC in totally healthy subjects.
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Deletion and missense or nonsense mutation of RAB39B gene cause familial Parkinson's disease (PD). We hypothesized that deletion and mutation of RAB39B gene induce degeneration of dopaminergic neurons by decreasing protein level of functional RAB39B and causing RAB39B deficiency. Cellular model of deletion or mutation of RAB39B gene-induced PD was prepared by knocking down endogenous RAB39B in human SH-SY5Y dopaminergic cells. Transfection of shRNA-induced 90% reduction in RAB39B level significantly decreased viability of SH-SY5Y dopaminergic neurons. Deficiency of RAB39B caused impairment of macroautophagy/autophagy, which led to increased protein levels of α-synuclein and phospho-α-synucleinSer129 within endoplasmic reticulum (ER) and mitochondria. RAB39B deficiency-induced increase of ER α-synuclein and phospho-α-synucleinSer129 caused activation of ER stress, unfolded protein response, and ER stress-induced pro-apoptotic cascade. Deficiency of RAB39B-induced increase of mitochondrial α-synuclein decreased mitochondrial membrane potential and increased mitochondrial superoxide. RAB39B deficiency-induced activation of ER stress pro-apoptotic pathway, mitochondrial dysfunction, and oxidative stress caused apoptotic death of SH-SY5Y dopaminergic cells by activating mitochondrial apoptotic cascade. In contrast to neuroprotective effect of wild-type RAB39B, PD mutant (T168K), (W186X), or (G192R) RAB39B did not prevent tunicamycin- or rotenone-induced increase of neurotoxic α-synuclein and activation of pro-apoptotic pathway. Our results suggest that RAB39B is required for survival and macroautophagy function of dopaminergic neurons and that deletion or PD mutation of RAB39B gene-induced RAB39B deficiency induces apoptotic death of dopaminergic neurons via impairing autophagy function and upregulating α-synuclein.
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Estresse do Retículo Endoplasmático , Neuroblastoma , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , Autofagia , Neurônios Dopaminérgicos/metabolismo , Mitocôndrias/metabolismo , Neuroblastoma/metabolismo , Estresse Oxidativo , Proteínas rab de Ligação ao GTP/metabolismoRESUMO
The dynamic pulse reaction (Nogier reflex), Reflex-Auriculo-Cardiac (RAC), or vascular autonomic signal is a physiologic phenomenon that is not fully accepted and widely understood in contemporary medical practice. In order to provide appropriate scientific evidence for better understanding, qualitative and-above all-quantitative research in this area is necessary. In this short report, 2 recordings of dynamic pulse reactions based on an analysis performed on a modified smartphone are demonstrated during laser acupuncture experiments using stimulation at ear acupuncture points.
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BACKGROUND: Cyclin C (CCNC) was reported to take part in regulating mitochondria-derived oxidative stress under cisplatin stimulation. However, its effect in gastric cancer is unknown. This study aimed to investigate the role of cyclin C and its ubiquitylation in regulating cisplatin resistance in gastric cancer. METHODS: The interaction between HECT domain and ankyrin repeat-containing E3 ubiquitin-protein ligase 1 (HACE1) and cyclin C was investigated by GST pull-down assay, co-immunoprecipitation and ubiquitylation assay. Mitochondria-derived oxidative stress was studied by MitoSOX Red assay, seahorse assay and mitochondrial membrane potential measurement. Cyclin C-associated cisplatin resistance was studied in vivo via xenograft. RESULTS: HACE1 catalysed the ubiquitylation of cyclin C by adding Lys11-linked ubiquitin chains when cyclin C translocates to cytoplasm induced by cisplatin treatment. The ubiquitin-modified cyclin C then anchor at mitochondira, which induced mitochondrial fission and ROS synthesis. Depleting CCNC or mutation on the ubiquitylation sites decreased mitochondrial ROS production and reduced cell apoptosis under cisplatin treatment. Xenograft study showed that disrupting cyclin C ubiquitylation by HACE1 conferred impairing cell apoptosis response upon cisplatin administration. CONCLUSIONS: Cyclin C is a newly identified substrate of HACE1 E3 ligase. HACE1-mediated ubiquitylation of cyclin C sheds light on a better understanding of cisplatin-associated resistance in gastric cancer patients. Ubiquitylation of cyclin C by HACE1 regulates cisplatin-associated sensitivity in gastric cancer. With cisplatin-induced nuclear-mitochondrial translocation of cyclin C, its ubiquitylation by HACE1 increased mitochondrial fission and mitochondrial-derived oxidative stress, leading to cell apoptosis.
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Cisplatino , Neoplasias Gástricas , Cisplatino/farmacologia , Ciclina C/genética , Humanos , Neoplasias Gástricas/tratamento farmacológico , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , UbiquitinaçãoRESUMO
Our previous study suggests that upregulated RAB35 is implicated in etiology of Parkinson's disease (PD). We hypothesized that upregulated RAB35 results from single nucleotide polymorphisms (SNPs) in RAB35 gene promoter. We identified SNPs within RAB35 gene promoter by analyzing DNA samples of discovery cohort and validation cohort. SNP rs17525453 within RAB35 gene promoter (T>C at position of -66) was significantly associated with idiopathic PD patients. Compared to normal controls, sporadic PD patients had higher C allele frequency. CC and CT genotype significantly increased risk of PD compared with TT genotype. SNP rs17525453 within RAB35 gene promoter leads to formation of transcription factor TFII-I binding site. Results of EMSA and supershift assay indicated that TFII-I binds to rs17525453 sequence of RAB35 gene promoter. Luciferase reporter assays showed that rs17525453 variant of RAB35 gene promoter possesses an augmented transcriptional activity. Our results suggest that functional variant rs17525453 within RAB35 gene promoter is likely to enhance transcriptional activity and upregulate RAB35 protein, which could lead to increased risk of PD in Taiwanese population.
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Estudos de Associação Genética , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Proteínas rab de Ligação ao GTP/genética , Povo Asiático/genética , Estudos de Coortes , Frequência do Gene , Genética Populacional , Genótipo , Humanos , Doença de Parkinson/epidemiologia , Risco , Taiwan/epidemiologia , Transcrição Gênica/genética , Regulação para Cima/genética , Proteínas rab de Ligação ao GTP/metabolismoRESUMO
Achilles tendinopathy has a high re-injury rate and poor prognosis. Development of effective therapy for Achilles tendinopathy is important. Excessive accumulation of ROS and resulting oxidative stress are believed to cause tendinopathy. Overproduction of hydrogen peroxide (H2O2), the most common ROS, could lead to the tendinopathy by causing oxidative damage, activation of endoplasmic reticulum (ER) stress and apoptotic death of tenocytes. Activation of mitochondrial aldehyde dehydrogenase 2 (ALDH2) is expected to alleviate oxidative stress and ER stress. Alda-1 is a selective and potent activator of ALDH2. In this study, we examined the cytoprotective benefit of Alda-1, an activator of ALDH2, on H2O2-induced Achilles tendinopathy in cellular and mouse models. We prepared cellular and mouse models of Achilles tendinopathy by treating cultured Achilles tenocytes and Achilles tendons with oxidative stressor H2O2. Subsequently, we studied the protective benefit of Alda-1 on H2O2-induced Achilles tendinopathy. Alda-1 pretreatment attenuated H2O2-induced cell death of cultured Achilles tenocytes. Treatment of Alda-1 prevented H2O2-induced oxidative stress and depolarization of mitochondrial membrane potential in tenocytes. Application of Alda-1 attenuated H2O2-triggered mitochondria- and ER stress-mediated apoptotic cascades in cultured tenocytes. Alda-1 treatment ameliorated the severity of H2O2-induced Achilles tendinopathy in vivo by preventing H2O2-induced pathological histological features of Achilles tendons, apoptotic death of Achilles tenocytes and upregulated expression of inflammatory cytokines IL-1ß and TNF-α. Our results provide the evidence that ALDH2 activator Alda-1 ameliorates H2O2-induced Achilles tendinopathy. Alda-1 could be used for preventing and treating Achilles tendinopathy.
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Tendão do Calcâneo/metabolismo , Aldeído-Desidrogenase Mitocondrial/metabolismo , Benzamidas/uso terapêutico , Benzodioxóis/uso terapêutico , Modelos Animais de Doenças , Tendinopatia/tratamento farmacológico , Tendinopatia/metabolismo , Tendão do Calcâneo/efeitos dos fármacos , Tendão do Calcâneo/patologia , Animais , Benzamidas/farmacologia , Benzodioxóis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Peróxido de Hidrogênio/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Tendinopatia/patologia , Tenócitos/efeitos dos fármacos , Tenócitos/metabolismo , Tenócitos/patologiaRESUMO
MicroRNAs (miRs) downregulate or upregulate the mRNA level by binding to the 3'-untranslated region (3'UTR) of target gene. Dysregulated miR levels can be used as biomarkers of Parkinson's disease (PD) and could participate in the etiology of PD. In the present study, 45 brain-enriched miRs were evaluated in serum samples from 50 normal subjects and 50 sporadic PD patients. The level of miR-204-5p was upregulated in serum samples from PD patients. An upregulated level of miR-204-5p was also observed in the serum and substantia nigra (SN) of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. Expression of miR-204-5p increased the level of α-synuclein (α-Syn), phosphorylated (phospho)-α-Syn, tau, or phospho-tau protein and resulted in the activation of endoplasmic reticulum (ER) stress in SH-SY5Y dopaminergic cells. Expression of miR-204-5p caused autophagy impairment and activation of c-Jun N-terminal kinase (JNK)-mediated apoptotic cascade in SH-SY5Y dopaminergic cells. Our study using the bioinformatic method and dual-luciferase reporter analysis suggests that miR-204-5p positively regulates mRNA expression of dual-specificity tyrosine phosphorylation regulated kinase 1A (DYRK1A) by directly interacting with 3'UTR of DYRK1A. The mRNA and protein levels of DYRK1A were increased in SH-SY5Y dopaminergic cells expressing miR-204-5p and SN of MPTP-induced PD mouse model. Knockdown of DYRK1A expression or treatment of the DYRK1A inhibitor harmine attenuated miR-204-5p-induced increase in protein expression of phospho-α-Syn or phospho-tau, ER stress, autophagy impairment, and activation of JNK-mediated apoptotic pathway in SH-SY5Y dopaminergic cells or primary cultured dopaminergic neurons. Our results suggest that upregulated expression of miR-204-5p leads to the death of dopaminergic cells by targeting DYRK1A-mediated ER stress and apoptotic signaling cascade.
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BACKGROUND AND PURPOSE: It is essential to develop a reliable predictive serum biomarker for Parkinson's disease (PD). The accumulation of alpha-synuclein (αSyn) and up-regulated expression of Rab35 participate in the etiology of PD. The purpose of this investigation was to determine whether the combined assessment of serum αSyn and Rab35 is a useful predictive biomarker for PD. METHODS: Serum levels of αSyn or Rab35 were determined in serum samples from 59 sporadic PD patients, 19 progressive supranuclear palsy (PSP) patients, 20 multiple system atrophy (MSA) patients, and 60 normal controls (NC). Receiver operating characteristics (ROC) curves were calculated to determine the diagnostic accuracy of αSyn or/and Rab35 in discriminating PD patients from NC or atypical parkinsonian patients. RESULTS: The levels of αSyn and Rab35 were increased in PD patients. The serum level of Rab35 was positively correlated with that of αSyn in PD patients. Compared to analyzing αSyn or Rab35 alone, the combined analysis of αSyn and Rab35 produced a larger area under the ROC curve and performed better in discriminating PD patients from NC, MSA patients, or PSP patients. When age was dichotomized at 55, 60, 65, or 70 years, the combined assessment of αSyn and Rab35 for classifying PD was better in the group below the cutoff age than in the group above the cutoff age. CONCLUSIONS: Combined assessment of serum αSyn and Rab35 is a better biomarker for discriminating PD patients from NC or atypical parkinsonian patients, and is a useful predictive biomarker for younger sporadic PD patients.
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Purpose: To investigate the mitochondria-related mechanism of Gynura segetum (GS)-induced apoptosis and the protective effect of phosphocreatine (PCr), a mitochondrial respiration regulator. Methods: First, the mechanism was explored in human hepatocyte cell line. The mitochondrial oxidative stress was determined by fluorescence assay. The level of sirtuin 3 (SIRT3), acetylated superoxide dismutase 2 (Ac-SOD2), SOD2, and apoptosis were detected by Western blotting. Mito-TEMPO and cell lines of viral vector-mediated overexpression of SIRT3 and SIRT3H248Y were used to further verify the mechanism of GS-induced apoptosis. GS-induced liver injury mice models were built by GS through intragastric administration and interfered by PCr through intraperitoneal injection. A total of 30 C57BL/6J mice were assigned to 5 groups and treated with either saline, PCr (100 mg/kg), GS (30 g/kg), or PCr (50 or 100 mg/kg)+GS (30 g/kg). Liver hematoxylin and eosin (HE) staining, immunohistochemical analysis, and blood biochemical evaluation were performed. Results: GS induced hepatocyte apoptosis and elevated levels of mitochondrial ROS in L-02 cells. The expression of SIRT3 was decreased. Downregulation of SIRT3 was associated with increased levels of Ac-SOD2, which is the inactivated enzymatic form of SOD2. Conversely, when overexpressing SIRT3 in GS-treated cells, SOD2 activity was restored, and mitochondrial ROS levels and hepatocyte apoptosis declined. Upon administration of PCr to GS-treated cells, they exhibited a significant upregulation of SIRT3 and were protected against apoptosis. In animal experiments, serum ALT level and mitochondrial ROS of the mice treated with GS and 50 mg/kg PCr were significantly attenuated compared with only GS treated. The changes in SIRT3 expression were also consistent with the in vitro results. In addition, immunohistochemical analysis of the mouse liver showed that Ac-SOD2 was decreased in the PCr and GS co-treated group compared with GS treated group. Conclusion: GS caused liver injury by dysregulating mitochondrial ROS generation via a SIRT3-SOD2 pathway. PCr is a potential agent to treat GS-induced liver injury by mitochondrial protection.
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Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Hepatócitos/efeitos dos fármacos , Fosfocreatina/farmacologia , Substâncias Protetoras/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Células HEK293 , Hepatócitos/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/análise , Sirtuína 3/antagonistas & inibidores , Sirtuína 3/metabolismo , Relação Estrutura-Atividade , Superóxido Dismutase/antagonistas & inibidores , Superóxido Dismutase/metabolismoRESUMO
PARK14 patients with homozygous (D331Y) PLA2G6 mutation display motor deficits of pure early-onset Parkinson's disease (PD). The aim of this study is to investigate the pathogenic mechanism of mutant (D331Y) PLA2G6-induced PD. We generated knockin (KI) mouse model of PARK14 harboring homozygous (D331Y) PLA2G6 mutation. Then, we investigated neuropathological and neurological phenotypes of PLA2G6D331Y/D331Y KI mice and molecular pathogenic mechanisms of (D331Y) PLA2G6-induced degeneration of substantia nigra (SN) dopaminergic neurons. Six-or nine-month-old PLA2G6D331Y/D331Y KI mice displayed early-onset cell death of SNpc dopaminergic neurons. Lewy body pathology was found in the SN of PLA2G6D331Y/D331Y mice. Six-or nine-month-old PLA2G6D331Y/D331Y KI mice exhibited early-onset parkinsonism phenotypes. Disrupted cristae of mitochondria were found in SNpc dopaminergic neurons of PLA2G6D331Y/D331Y mice. PLA2G6D331Y/D331Y mice displayed mitochondrial dysfunction and upregulated ROS production, which may lead to activation of apoptotic cascade. Upregulated protein levels of Grp78, IRE1, PERK, and CHOP, which are involved in activation of ER stress, were found in the SN of PLA2G6D331Y/D331Y mice. Protein expression of mitophagic proteins, including parkin and BNIP3, was downregulated in the SN of PLA2G6D331Y/D331Y mice, suggesting that (D331Y) PLA2G6 mutation causes mitophagy dysfunction. In the SN of PLA2G6D331Y/D331Y mice, mRNA levels of eight genes that are involved in neuroprotection/neurogenesis were decreased, while mRNA levels of two genes that promote apoptotic death were increased. Our results suggest that PARK14 (D331Y) PLA2G6 mutation causes degeneration of SNpc dopaminergic neurons by causing mitochondrial dysfunction, elevated ER stress, mitophagy impairment, and transcriptional abnormality.
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Neurônios Dopaminérgicos/patologia , Estresse do Retículo Endoplasmático , Técnicas de Introdução de Genes , Fosfolipases A2 do Grupo VI/genética , Mitofagia , Degeneração Neural/patologia , Doença de Parkinson/genética , Substância Negra/patologia , Animais , Apoptose , Sequência de Bases , Modelos Animais de Doenças , Chaperona BiP do Retículo Endoplasmático , Regulação da Expressão Gênica , Homozigoto , Humanos , Corpos de Lewy/patologia , Camundongos Endogâmicos C57BL , Mitocôndrias/patologia , Mitocôndrias/ultraestrutura , Mutação/genética , Neuroproteção , Doença de Parkinson/patologia , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
HACE1 E3 ligase was discovered to be down-regulated in several cancers while its role in regulating tumors was merely understood. This study aimed to explore the specific effect of HACE1 played in gastric tumorigenesis and its potential mechanism. HACE1's expression was found significantly lower in gastric cancer tissues compared with the adjacent normal tissues (P < 0.001). Its protein level in gastric cancer negatively correlated to tumor pathological differentiation (P = 0.019). And in gastric cancer patients with TNM I-IIIa, those with lower HACE1 protein level had poorer overall survival (P = 0.025). Studies, in vivo and in vitro, showed that overexpressing HACE1 inhibited tumor proliferation and migration, and enhanced cell apoptosis. Besides, ectopic expression of HACE1 down-regulated the protein level of ß-catenin and inhibited the activity of the Wnt/ß-catenin signaling pathway. All the cellular functions were abolished when we overexpressed inactive HACE1-deltaHECT. Above all, we demonstrated that HACE1 E3 ligase played a suppressive role in gastric tumorigenesis and inhibited the activity of the Wnt/ß-catenin signaling pathway. Circumventing the decline of HACE1 in early stage of carcinoma may impede the tumorigenesis and malignant process of gastric cancer.
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Expressão Gênica , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Ubiquitina-Proteína Ligases/genética , Adulto , Idoso , Animais , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Progressão da Doença , Feminino , Técnicas de Inativação de Genes , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidade , Ubiquitina-Proteína Ligases/metabolismo , Via de Sinalização Wnt , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Mutations in the gene encoding Ca2+-independent phospholipase A2 group 6 (PLA2G6) cause the recessive familial type 14 of Parkinson's disease (PARK14). Mitochondrial dysfunction is involved in the pathogenesis of Parkinson's disease (PD). PLA2G6 is believed to be required for maintaining mitochondrial function. In the present study, rotenone-induced cellular model of PD was used to investigate possible molecular pathogenic mechanism of PARK14 mutant PLA2G6-induced PD. Overexpression of wild-type (WT) PLA2G6 ameliorated rotenone-induced apoptotic death of SH-SY5Y dopaminergic cells. PARK14 mutant (D331Y), (G517C), (T572I), (R632W), (N659S) or (R741Q) PLA2G6 failed to prevent rotenone-induced activation of mitochondrial apoptotic pathway and exert a neuroprotective effect. WT PLA2G6, but not PARK14 mutant PLA2G6, prevented rotenone-induced mitophagy impairment. In contrast to WT PLA2G6, PARK14 mutant PLA2G6 was ineffective in attenuating rotenone-induced decrease in mitochondrial membrane potential and increase in the level of mitochondrial superoxide. WT PLA2G6, but not PARK14 PLA2G6 mutants, restored enzyme activity of mitochondrial complex I and cellular ATP content in rotenone-treated SH-SY5Y dopaminergic cells. In contrast to WT PLA2G6, PARK14 mutant PLA2G6 failed to prevent rotenone-induced mitochondrial lipid peroxidation and cytochrome c release. These results suggest that PARK14 PLA2G6 mutants lose their ability to maintain mitochondrial function and are defective inpreventing mitochondrial dysfunction, ROS production and activation of mitochondrial apoptotic pathway in rotenone-induced cellular model of PD.
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Mutation of leucine-rich repeat kinase 2 (LRRK2) is the most common genetic cause of both familial and sporadic Parkinson's disease (PD) cases. Several mutations in LRRK2 gene were reported in PD patients. R1441 is the second most frequent site of LRRK2 mutation. We generated (R1441C) LRRK2 transgenic mice that displayed motor deficits at the age of 16 months. Compared with wild-type mice, 16-month-old (R1441C) LRRK2 mice exhibited a significant reduction in the number of substantia nigra (SN) dopaminergic neurons. To elucidate molecular pathogenic pathways involved in (R1441C) LRRK2-induced death of SN dopaminergic neurons, we performed microarray analysis to visualize altered mRNA expressions in the SN of (R1441C) LRRK2 mouse. In the SN of (R1441C) LRRK2 transgenic mouse, the mRNA expression of three genes that promote cell death was upregulated, while the mRNA expression of seven genes that contribute to neurogenesis/neuroprotection was significantly downregulated. Our results suggest that altered expression of these genes involved in regulating neuronal survival may contribute to the pathogenesis of (R1441C) LRRK2-induced PD.
Assuntos
Sobrevivência Celular/genética , Neurônios Dopaminérgicos/metabolismo , Regulação da Expressão Gênica , Degeneração Neural/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Substância Negra/metabolismo , Animais , Neurônios Dopaminérgicos/patologia , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Levodopa/farmacologia , Camundongos , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Atividade Motora/genética , Degeneração Neural/genética , Degeneração Neural/patologia , Neurogênese/genética , Proteínas Serina-Treonina Quinases/genética , Substância Negra/patologiaRESUMO
More studies are required to develop therapeutic agents for treating spinocerebellar ataxia type 3 (SCA3), which is caused by mutant polyglutamine-expanded ataxin-3 and is the most prevalent subtype of spinocerebellar ataxias. T1-11 [N6-(4-Hydroxybenzyl) adenosine], isolated from a Chinese medicinal herb Gastordia elata, is an adenosine A2A receptor agonist. SCA3 and Huntington's disease (HD) belong to a family of polyglutamine neurodegenerative diseases. T1-11 exerted a therapeutic effect on HD transgenic mouse by decreasing protein level of polyglutamine-expanded huntingtin in the striatum. In the present study, we test the possibility that T1-11 or JMF1907 [N6-(3-Indolylethyl) adenosine], a synthetic analog of T1-11, alleviates pontine neuronal death, cerebellar transcriptional downregulation and ataxic symptom in the SCA3 transgenic mouse expressing HA-tagged polyglutamine-expanded ataxin-3-Q79 (ataxin-3-Q79HA). Daily oral administration of T1-11 or JMF1907 prevented neuronal death of pontine nuclei in the SCA3 mouse with a dose-dependent manner. Oral application of T1-11 or JMF1907 reversed mutant ataxin-3-Q79-induced cerebellar transcriptional repression in the SCA3 transgenic mouse. T1-11 or JMF1907 ameliorated the symptom of motor incoordination displayed by SCA3 mouse. Oral administration of T1-11 or JMF1907 significantly decreased protein level of ataxin-3-Q79HA in the pontine nuclei or cerebellum of SCA3 mouse. T1-11 or JMF1907 significantly augmented the chymotrypsin-like activity of proteasome in the pontine nuclei or cerebellum of SCA3 mouse. Our results suggests that T1-11 and JMF1907 alleviate pontine neuronal death, cerebellar transcriptional downregulation and ataxic symptom of SCA3 transgenic mouse by augmenting the proteasome activity and reducing the protein level of polyglutamine-expanded ataxin-3-Q79 in the pontine nuclei and cerebellum.
Assuntos
Adenosina/análogos & derivados , Indóis/farmacologia , Doença de Machado-Joseph/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Adenosina/farmacologia , Administração Oral , Animais , Ataxina-3/genética , Ataxina-3/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Cerebelo/patologia , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Humanos , Doença de Machado-Joseph/patologia , Doença de Machado-Joseph/fisiopatologia , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Ponte/efeitos dos fármacos , Ponte/metabolismo , Ponte/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteína X Associada a bcl-2/metabolismo , Proteína bcl-X/metabolismoRESUMO
OBJECTIVE: We propose applying objective structured clinical examinations (OSCEs) and discuss the educational efficacy of such examinations regarding the clinical competence of traditional Chinese medicine (TCM) practitioners. DESIGN: TCM OSCEs were implemented for evaluation and instruction from 2011 to 2013. Trainees received feedback from clinician-educators and standardized patients. Trainees' survey data were extracted from post-OSCE questionnaires and interviews to analyze TCM OSCEs. RESULTS: Five TCM OSCEs were administered, and the educational backgrounds of the 37 participants were analyzed. According to analysis of the questionnaires, all trainees agreed OSCEs were beneficial. In interviews, trainees expressed appreciation for the direct, real-time feedback during the OSCE and felt it closely resembled actual clinical work. However, the simulation models of OSCEs must be upgraded. CONCLUSIONS: OSCEs can be used in evaluating, teaching, and certifying TCM clinical competencies to improve the quality of TCM practices. The patient-centered training aspect of TCM OSCEs is particularly helpful for participants.
Assuntos
Competência Clínica/normas , Terapias Complementares/educação , Medicina Tradicional Chinesa/normas , HumanosRESUMO
Our previous study using a transgenic mouse model of spinocerebellar ataxia type 3 (SCA3) reported that disease-causing ataxin-3-Q79 caused cerebellar malfunction by inducing transcriptional downregulation. Long-term depression (LTD) of parallel fiber-Purkinje neuron glutamatergic transmission is believed to be a cellular mechanism for motor learning and motor coordination in the cerebellum. Downregulated mRNA expression of calcineurin B, IP3-R1, myosin Va and PLC ß4, which are required for the induction of cerebellar LTD, led to an impairment of LTD induction in Purkinje neurons of SCA3 transgenic mouse. Our study suggested that ataxin-3-Q79 caused hypoacetylation of cerebellar histone H3 or H4 by inhibiting the activity of histone acetyltransferase (HAT) without affecting the activity of histone deacetylase (HDAC). Consistent with the hypothesis that hypoacetylated H3 or H4 histone associated with promoter regions of downregulated genes is the molecular mechanism underlying ataxin-3-Q79-induced transcriptional repression, chromatin immunoprecipitation-quantitative real-time PCR analysis showed hypoacetylation of H3 or H4 histone associated with the proximal promoter of downregulated calcineurin B, IP3-R1, myosin Va or PLC ß4 gene in the cerebellum of SCA3 mouse. HDAC inhibitor sodium butyrate reversed ataxin-3-Q79-induced hypoacetylation of histone H3 or H4 associated with the proximal promoter of calcineurin B, IP3-R1, myosin Va or PLC ß4 gene. Sodium butyrate also prevented ataxin-3-Q79-induced impairment of LTD induction in Purkinje neurons of SCA3 mice. Our results suggest that polyglutamine-expanded ataxin-3-Q79 impairs HAT activity, leading to histone hypoacetylation, downregulated expression of cerebellar genes required for LTD induction and impaired induction of cerebellar LTD in the SCA3 transgenic mouse.