Creatine chemical exchange saturation transfer (CEST) CMR imaging reveals myocardial early involvement in idiopathic inflammatory myopathy at 3T: feasibility and initial experience.

OBJECTIVES: To measure creatine distribution in idiopathic inflammatory myopathy (IIM) patients' myocardial segments and investigate whether cardiovascular magnetic resonance (CMR) chemical exchange saturation transfer (CEST) creatine mapping can detect subclinical myocardial changes, CEST's ability was further compared with other conventional CMR mapping sequences. METHODS: Forty IIM patients (53.5 ± 10.5 years, 26 males) and eight healthy controls (35.4 ± 6 years, 5 males) underwent CMR scans on a 3.0-T MR scanner. Patients with IIM were further classified into two subgroups according to cardiac troponin T (cTn-T) values: the elevated cTn-T subgroup (n = 14) and the normal cTn-T subgroup (n = 26). Cine imaging, T2 SPAIR, LGE imaging, T1 mapping, T2 mapping, and Cr (creatine) CEST were performed. RESULTS: Cr mapping showed significantly reduced creatine in IIM patients among global myocardium (IIM: 0.109 ± 0.063, controls: 0.121 ± 0.021, p < 0.05), and decreased creatine signals were detected in all 16 cardiac segments (p < 0.05). Patients also had significantly prolonged native T1 and decreased enhanced T1 values in each cardiac segment (p < 0.05). There was no significant difference of LVEF and T2 values between IIM patients and controls. Between the two subgroups, elevated cTn-T was linked with creatine and extracellular volume fraction (ECV) values, providing a global average creatine signal of 0.107 vs 0.112 (p < 0.05) and 24.7 vs 32.4 (p < 0.05). CONCLUSION: Creatine CEST mapping can detect early-stage heart involvement with negative LGE findings in IIM. Compared with T1 mapping, CEST provides increased sensitivity to ECV measurement, making it significantly better than T1, and a promising CMR sequence for screening subclinical myocardial damage. KEY POINTS: • IIM patients with potential or ongoing heart involvement, elevated ECV, and reduced Cr CEST values could provide valuable information. • ECV and Cr CEST values were closely related to elevated cTn-T.

A positive feedback loop between STAT3 and cyclooxygenase-2 gene may contribute to Helicobacter pylori-associated human gastric tumorigenesis.

Persistent infection with Helicobacter pylori (H. pylori) contributes to gastric diseases including chronic gastritis and gastric cancer. However, the pathogenesis of this carcinogenic bacterium has not been completely elucidated. Here, we report that H. pylori rapidly triggers STAT3 signaling and induces STAT3-dependent COX-2 expression both in vitro and in vivo. STAT3 upregulates COX-2 by binding to and increasing the activity of COX-2 promoter. COX-2 in turn regulates IL-6/STAT3 signaling under basal conditions and during H. pylori infection. These findings suggest that a positive feedback loop between STAT3 and COX-2 exists in the basal condition and H. pylori infectious condition. Immunohistochemical staining revealed that H. pylori-positive gastritis tissues exhibited markedly higher levels of pSTAT3(Tyr705) than H. pylori-negative ones. High pSTAT3(Tyr705) levels are correlated with intestinal metaplasia and dysplasia, suggesting pSTAT3(Tyr705) may be useful in the early detection of gastric tumorigenesis. Additionally, a strong positive correlation between STAT3/pSTAT3(Tyr705) levels and COX-2 expression was identified in gastritis and gastric cancer tissues. Together, these findings provide new evidence for a positive feedback loop between STAT3 signaling and COX-2 in H. pylori pathogenesis and may lead to new approaches for early detection and effective therapy of gastric cancer

Role of STAT3 and vitamin D receptor in EZH2-mediated invasion of human colorectal cancer.

The polycomb group protein enhancer of zeste homologue 2 (EZH2), which has histone methyltransferase (HMT) activity, is overexpressed in malignant tumours. However, the role of EZH2 in colorectal cancer (CRC) invasion is little known. Here we investigated the clinical significance, biological effects, and mechanisms of EZH2 signalling. Knockdown of EZH2 significantly reduced cell invasion and secretion of matrix metalloproteinases 2/9 (MMP2/9) in in vitro studies. Knockdown of EZH2 dramatically increased overall survival and decreased metastasis of lung in in vivo studies. Conversely, overexpression of EZH2 significantly increased lung metastasis and shortened overall survival when compared with control tumours. EZH2-induced CRC cell invasion may depend on down-regulation of vitamin D receptor (VDR), which is considered to be a marker of CRC invasion. EZH2 regulates the histone trimethylation of lysine 27 (H3K27me3) in the VDR promoter. Moreover, we found that STAT3 directly binds to the EZH2 promoter and regulates VDR down-regulation in CRC cells. Significant inverse correlations were observed between the expression of EZH2 and pSTAT3 and that of VDR in CRC tissues compared with normal tissue in patients. We show the role of EZH2 in CRC metastasis and identify VDR as a target gene of EZH2. EZH2 expression may be directly regulated by STAT3, and STAT3 may play an important role in EZH2-mediated VDR down-regulation in CRC. This pathway may provide potential targets in aggressive CRC.

Roles of STAT3 and ZEB1 proteins in E-cadherin down-regulation and human colorectal cancer epithelial-mesenchymal transition.

The progression of colorectal carcinoma (CRC) to invasive and metastatic disease may involve localized occurrences of epithelial-mesenchymal transition (EMT). However, mechanisms of the EMT process in CRC progression are not fully understood. We previously showed that knockdown of signal transducer and activator of transcription 3 (STAT3) up-regulated E-cadherin (a key component in EMT progression) in CRC. In this study, we examined the roles of STAT3 in CRC EMT and ZEB1, an EMT inducer, in STAT3-induced down-regulation of E-cadherin. Knockdown of STAT3 significantly increased E-cadherin and decreased N-cadherin and vimentin expressions in highly invasive LoVo CRC cells. Meanwhile, overexpression of STAT3 significantly reduced E-cadherin and enhanced N-cadherin and vimentin expressions in weakly invasive SW1116 CRC cells. Activation of STAT3 significantly increased CRC cell invasiveness and resistance to apoptosis. Knockdown of STAT3 dramatically enhanced chemosensitivity of CRC cells to fluorouracil. STAT3 regulated ZEB1 expression in CRC cells, and the STAT3-induced decrease in E-cadherin and cell invasion depended on activation of ZEB1 in CRC cells. Additionally, pSTAT3(Tyr-705) and ZEB1 expressions were significantly correlated with TNM (tumor, lymph node, and metastasis stages) (p < 0.01). In conclusion, STAT3 may directly mediate EMT progression and regulate ZEB1 expression in CRC. ZEB1 may participate in STAT3-induced cell invasion and E-cadherin down-regulation in CRC cells. The expressions of pSTAT3(Tyr-705) and ZEB1 may be positively associated with CRC metastasis. Our data may provide potential targets to prevent and/or treat CRC invasion and metastasis.

Identification of potential target genes of butyrate in dimethylhydrazine-induced colorectal cancer in mice.

The mechanism by which butyrate prevents colorectal cancer (CRC) is unclear. The objective of this study was to identify potential target genes of butyrate in 1,2-dimethylhydrazine (DMH)-induced CRC in mice. Nontumor colorectal tissues of mice from DMH + butyrate, DMH, and control groups were hybridized on Agilent Mouse Whole Genome 44K Oligo Microarrays. Selected genes were validated by qRT-PCR. Data was further analyzed by KEGG, gene ontology (GO), and pathway studio software. The tumor incidence in the DMH + butyrate and DMH groups was 30% and 90%, respectively (P < 0.05). There were 355 genes downregulated due to DMH treatment while upregulated by butyrate, and 475 genes upregulated by DMH while downregulated by butyrate. The results revealed that most of the tumor-related signaling pathways (e.g., MAPK pathway, Wnt pathway, insulin pathway, and VEGF pathway) were downregulated by butyrate. The GO terms related to cell differentiation, cell cycle, cell proliferation, cell death, cell adhesion, and cell migration were significantly affected. The chemopreventive effects of butyrate were confirmed in the DMH-induced CRC mice model. And mechanisms encompassing multiple pathways and GO terms are involved in the regulation of gene expression.

Inhibition of JAK2/STAT3 signalling induces colorectal cancer cell apoptosis via mitochondrial pathway.

Abnormalities in the JAK2/STAT3 pathway are involved in the pathogenesis of colorectal cancer (CRC), including apoptosis. However, the exact mechanism by which dysregulated JAK2/STAT3 signalling contributes to the apoptosis has not been clarified. To investigate the role of both JAK2 and STAT3 in the mechanism underlying CRC apoptosis, we inhibited JAK2 with AG490 and depleted STAT3 with a small interfering RNA. Our data showed that inhibition of JAK2/STAT3 signalling induced CRC cellular apoptosis via modulating the Bcl-2 gene family, promoting the loss of mitochondrial transmembrane potential (Δψm) and the increase of reactive oxygen species. In addition, our results demonstrated that the translocation of cytochrome c (Cyt c), caspase activation and cleavage of poly (ADP-ribose) polymerase (PARP) were present in apoptotic CRC cells after down-regulation of JAK2/STAT3 signalling. Moreover, inhibition of JAK2/STAT3 signalling suppressed CRC xenograft tumour growth. We found that JAK2/STAT3 target genes were decreased; meanwhile caspase cascade was activated in xenograft tumours. Our findings illustrated the biological significance of JAK2/STAT3 signalling in CRC apoptosis, and provided novel evidence that inhibition of JAK2/STAT3 induced apoptosis via the mitochondrial apoptotic pathway. Therefore, JAK2/STAT3 signalling may be a potential target for therapy of CRC.

STAT5 isoforms regulate colorectal cancer cell apoptosis via reduction of mitochondrial membrane potential and generation of reactive oxygen species.

Although the two isoforms of signal transducer and activator of transcription 5 (STAT5) protein, STAT5a and STAT5b, have 94% sequence identity, they are encoded by different genes. Previous studies have been unable to define clearly the roles of the STAT5 genes in colorectal cancer (CRC). To investigate the role of STAT5 isoforms in CRC oncogenesis, immunohistochemical staining was performed. Colorectal adenocarcinomas showed higher expression of STAT5a/5b than normal colonic mucosa (P < 0.05), and STAT5b expression was significantly higher than that of STAT5a in colorectal adenocarcinoma tissue (P < 0.05). Furthermore, STAT5b expression was significantly associated with TNM stage. To delineate the roles of STAT5a/5b in CRC carcinogenesis, we studied CRC cells depleted of each isoform by treating the cells with small interfering RNA. Both STAT5a and STAT5b were found to be involved in cell growth, cell cycle progression, and apoptosis of CRC cells, and exerted their effects via the regulation of downstream targets of the STAT genes. However, STAT5b influenced CRC cell apoptosis more than STAT5a (P < 0.05), reducing mitochondrial membrane potential and generating reactive oxygen species. In conclusion, both isoforms of STAT5 are involved in the growth and cell cycle progression of CRC cells, STAT5b could play a more important role than STAT5a in the clinicopathological characteristics of CRC and CRC cell apoptosis.

[Study on the changes of cardiac reserve function during normal vaginal delivery].

OBJECTIVE: To investigate the trend of cardiac reserve function during the normal labor. METHODS: Sixty-three cases were chosen randomly from hospitalized maternal women in the First Affiliated Hospital of Chongqing Medical University from 2010 June to December (six months). The digital technique of heart sound signal processing was used to analyze cardiac reserve function parameters including the heart rate (HR), the ratio of the amplitude of the first heart sound to the second heart sound (S1/S2) and the ratio of diastolic to systolic duration (D/S) of pregnant women. RESULTS: (1) Comparisons of cardiac reserve function between uterine contractions and relaxations during labor: 1) Latent phase of labor (cervix dilation < 3 cm):HR was (87.3 ± 14.0) beats/min in uterine contractions and (82.8 ± 12.5) beats/min in uterine relaxations, the ratio of D/S was 1.14 ± 0.27 in uterine contractions and 1.21 ± 0.22 in uterine relaxations, the comparisons of the above two were statistically significant, P < 0.05; But the ratio of S1/S2 was 2.19 ± 0.82 in uterine contractions and 2.28 ± 0.81 in uterine relaxations, the comparison was not statistically significant, P > 0.05. 2) During early active stage of labor (cervix dilation 3 - 6 cm):HR was (89.3 ± 15.4) beats/min in uterine contractions and (83.1 ± 13.5) beats/min in uterine relaxations, the ratio of D/S was 1.09 ± 0.30 in uterine contractions and 1.20 ± 0.27 in uterine relaxations, the comparisons of the above two were statistically significant, (P < 0.05); But the ratio of S1/S2 was 2.42 ± 1.08 in uterine contractions and 2.29 ± 0.83 in uterine relaxations, the comparison was not statistically significant (P > 0.05); 3) During late active stage of labor (cervix dilation 6 - 10 cm), HR was (95.4 ± 18.7) beats/min in uterine contractions and (86.2 ± 15.6) beats/min in uterine relaxations, the ratio of D/S was 1.01 ± 0.25 in uterine contractions and 1.18 ± 0.25 in uterine relaxations, the comparisons of the above two were statistically significant, (P < 0.05); But the ratio of S1/S2 was 2.61 ± 1.26 in uterine contractions and 2.67 ± 1.19 in uterine relaxations, the comparison was not statistically significant (P > 0.05). 4) The second stage of labor (cervical dilation ≥ 10 cm):HR was (109.4 ± 19.7) beats/min in uterine contractions and (93.5 ± 16.7) beats/min in uterine relaxations, the ratio of D/S was 0.89 ± 0.23 in uterine contractions and 1.14 ± 0.26 in uterine relaxations, the ratio of S1/S2 was 3.66 ± 1.37 in uterine contractions and (2.81 ± 1.07) in uterine relaxations, the comparisons of all were statistically significant (P < 0.05). (2) Comparison of cardiac reserve function in uterine relaxations of each stage of labor: 1) Maternal heart rate gradually increased from latent stage of labor to the second stage of labor, and decreased postpartum, the comparison was statistically significant (P < 0.05); 2) The ratio of S1/S2 of maternal gradually increased from latent stage of labor to the second stage of labor, and decreased postpartum, the comparison was statistically significant (P < 0.05); 3) The ratio of D/S gradually decreased from latency to the second stage of labor, and increased postpartum, the comparison was statistically significant (P < 0.05). (3) Comparison of cardiac reserve function in uterine contractions of each stage of labor: 1) Maternal heart rate gradually decreased from latent stage of labor to the second stage of labor, the comparison was statistically significant (P < 0.05); 2) The ratio of S1/S2 of maternal gradually increased from latent stage of labor to the second stage of labor, the comparison was statistically significant (P < 0.05); 3) The ratio of D/S gradually decreased from latency to the second stage of labor, the comparison was statistically significant (P < 0.05). CONCLUSIONS: The maternal cardiac reserve function decreased in uterine contractions than relaxation during labor; With the progress of labor, the maternal cardiac reserve function declined, especially in the second stage of labor, and recovered in postpartum stage.

The Potential Win-win Strategy for Healthy Aging and Environmental Protection: Environmental Volunteering.

PURPOSE: To explore the physical activity level of community environmental volunteering (CEV) participants and the differences in physical functions and daily activity patterns between the older adults who engaged in intensive CEV (≥15 hours/week) and non-intensive CEV (<15 hours/week) groups. DESIGN: Cross-sectional study. SETTING: Three recycling stations in Taiwan. SAMPLE: In total, 113 community-dwelling older adults who regularly participated in CEV. The response rate was 53%. MEASURES: The ActiGraph wGT3x-BT accelerometer for the percentage of sedentary, light, and moderate to vigorous physical activity (MVPA) of CEV time and awaken time; the Jamar hand dynamometer for grip strength; and the MicroFET3 muscle testing dynamometer for knee extension strength. ANALYSIS: Analysis of covariance with the baseline characteristics as covariates. RESULTS: Overall, MVPA, light, and sedentary activities accounted for 53.73%, 41.10%, and 5.23% of CEV time, respectively. The intensive group (n = 61) displayed greater dominant handgrip strength (P = .004) and higher MVPA percentage in daily life (P = .044) than the non-intensive group (n = 52). CONCLUSION: CEV provides sufficient opportunities for older adults to perform physical activity. Intensive CEV is related to greater handgrip strength but not lower limb strength. Further study is needed to establish the causal relationship between CEV and health variates.

Gene silencing by the Polycomb group proteins and associations with cancer.

Cancer not only is associated with inherited genetic sequences but also results from epigenetic changes. Thus, understanding the mechanisms underlying epigenetic modifications is important for cancer prevention, diagnosis, and therapy. There is much evidence showing that some Polycomb group (PcG) proteins are abnormally expressed in certain tumors. This review addresses biological functions and biochemical behaviors of the Polycomb repression complex proteins, including their enzymatic activities. Additionally, the potential mechanisms of PcG gene silencing by PcG and its link to cancers are summarized that will shed light on this novel area of study in cancer.

Methodological reporting of randomized controlled trials in major hepato-gastroenterology journals in 2008 and 1998: a comparative study.

BACKGROUND: It was still unclear whether the methodological reporting quality of randomized controlled trials (RCTs) in major hepato-gastroenterology journals improved after the Consolidated Standards of Reporting Trials (CONSORT) Statement was revised in 2001. METHODS: RCTs in five major hepato-gastroenterology journals published in 1998 or 2008 were retrieved from MEDLINE using a high sensitivity search method and their reporting quality of methodological details were evaluated based on the CONSORT Statement and Cochrane Handbook for Systematic Reviews of interventions. Changes of the methodological reporting quality between 2008 and 1998 were calculated by risk ratios with 95% confidence intervals. RESULTS: A total of 107 RCTs published in 2008 and 99 RCTs published in 1998 were found. Compared to those in 1998, the proportion of RCTs that reported sequence generation (RR, 5.70; 95%CI 3.11-10.42), allocation concealment (RR, 4.08; 95%CI 2.25-7.39), sample size calculation (RR, 3.83; 95%CI 2.10-6.98), incomplete outecome data addressed (RR, 1.81; 95%CI, 1.03-3.17), intention-to-treat analyses (RR, 3.04; 95%CI 1.72-5.39) increased in 2008. Blinding and intent-to-treat analysis were reported better in multi-center trials than in single-center trials. The reporting of allocation concealment and blinding were better in industry-sponsored trials than in public-funded trials. Compared with historical studies, the methodological reporting quality improved with time. CONCLUSION: Although the reporting of several important methodological aspects improved in 2008 compared with those published in 1998, which may indicate the researchers had increased awareness of and compliance with the revised CONSORT statement, some items were still reported badly. There is much room for future improvement.

Functional variant rs17525453 within RAB35 gene promoter is possibly associated with increased risk of Parkinson's disease in Taiwanese population.

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.

Alda-1, an activator of ALDH2, ameliorates Achilles tendinopathy in cellular and mouse models.

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.

(D620N) VPS35 causes the impairment of Wnt/ß-catenin signaling cascade and mitochondrial dysfunction in a PARK17 knockin mouse model.

Patients with familial type 17 of Parkinson's disease (PARK17) manifest autosomal dominant pattern and late-onset parkinsonian syndromes. Heterozygous (D620N) mutation of vacuolar protein sorting 35 (VPS35) is genetic cause of PARK17. We prepared heterozygous VPS35D620N/+ knockin mouse, which is an ideal animal model of (D620N) VPS35-induced autosomal dominant PARK17. Late-onset loss of substantia nigra pars compacta (SNpc) dopaminergic (DAergic) neurons and motor deficits of Parkinson's disease were found in 16-month-old VPS35D620N/+ mice. Normal function of VPS35-containing retromer is needed for activity of Wnt/ß-catenin cascade, which participates in protection and survival of SNpc DAergic neurons. It was hypothesized that (D620N) VPS35 mutation causes the malfunction of VPS35 and resulting impaired activity of Wnt/ß-catenin pathway. Protein levels of Wnt1 and nuclear ß-catenin were reduced in SN of 16-month-old VPS35D620N/+ knockin mice. Downregulated protein expression of survivin, which is a target gene of nuclear ß-catenin, and upregulated protein levels of active caspase-8 and active caspase-9 were observed in SN of VPS35D620N/+ mice at age of 16 months. VPS35 is involved in controlling morphology and function of mitochondria. Impaired function of VPS35 caused by (D620N) mutation could lead to abnormal morphology and malfunction of mitochondria. A significant decrease in mitochondrial size and resulting mitochondrial fragmentation was found in tyrosine hydroxylase-positive and neuromelanin-positive SNpc DAergic neurons of 16-month-old VPS35D620N/+ mice. Mitochondrial complex I activity or complex IV activity was reduced in SN of 16-month-old VPS35D620N/+ mice. Increased level of mitochondrial ROS and oxidative stress were found in SN of 16-month-old VPS35D620N/+ mice. Levels of cytosolic cytochrome c and active caspase-3 were increased in SN of VPS35D620N/+ mice aged 16 months. Our results suggest that PARK17 mutant (D620N) VPS35 impairs activity of Wnt/ß-catenin signaling pathway and causes abnormal morphology and dysfunction of mitochondria, which could lead to neurodegeneration of SNpc DAergic cells.

PARK14 (D331Y) PLA2G6 Causes Early-Onset Degeneration of Substantia Nigra Dopaminergic Neurons by Inducing Mitochondrial Dysfunction, ER Stress, Mitophagy Impairment and Transcriptional Dysregulation in a Knockin Mouse Model.

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.

Combined Assessment of Serum Alpha-Synuclein and Rab35 is a Better Biomarker for Parkinson's Disease.

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.

Upregulated Expression of MicroRNA-204-5p Leads to the Death of Dopaminergic Cells by Targeting DYRK1A-Mediated Apoptotic Signaling Cascade.

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.

Association between health service utilisation of internal migrant children and parents' acculturation in Guangdong, China: a cross-sectional study.

OBJECTIVES: To assess the health service utilisation of internal migrant children in Guangdong, China, and to explore the association between children's health service utilisation and their parents' acculturation. DESIGN: Cross-sectional survey between April and May 2016. SETTING: Six society-run schools of Tianhe and Baiyun districts in Guangzhou City of China. PARTICIPANTS: We recruited all students at grade 7 or 8 and one of their parents who resided in Guangzhou over 6 months without permanent registered residence (hukou) in Guangzhou (1161 pairs completed this survey). 258 children were ill within the past 2 weeks or during the last year. MAIN OUTCOME MEASURES: The main outcome was self-reported health service utilisation. Logistic regression analysis was conducted to explore the association between children's unmet needs for outpatient or inpatient service and their parents' acculturation (categorised into high, middle and low groups). RESULTS: In total, 216 children, or 18.6% of the total subjects, were ill within the past 2 weeks and were in need of outpatient service; 94 children, or 8.1% of the total subjects, were in need of inpatient service. Among them, 17.6% and 46.8% of the migrant children had unmet needs for outpatient and inpatient services, respectively. After controlling for enabling resources and predisposing characteristics, migrant children with parents in the middle-acculturation group (adjusted OR=3.17, 95% CIs 1.2 to 8.3, P<0.05) were more likely to have an unmet outpatient need than high-acculturation or low-acculturation groups, although only statistically significant when comparing with the high-acculturation group. Stratified analysis suggested that this association could be moderated by their family economic status. CONCLUSIONS: Our study suggested that the association between migrant children's health service utilisation and their parents' acculturation was complex and could be moderated by family economic status. Increasing the service utilisation among migrant children requires improving the acculturation and economic status of the parents of internal migrants.

CD44v6 overexpression related to metastasis and poor prognosis of colorectal cancer: A meta-analysis.

CD44v6 has recently been reported as a biomarker for colorectal cancer. However, the clinical and prognostic significance of CD44v6 in colorectal cancer remains controversial. Therefore, we performed a meta-analysis to clarify this issue. A comprehensive literature search was performed using Medline, Embase and Web of Science, and the statistical analysis was conducted using Stata software. A total of twenty-one studies including 3918 colorectal cancer cases were included. The pooled analysis showed that CD44v6 overexpression in colorectal cancer was an independent prognostic marker correlating with lower 5-year overall survival rate (OR=0.78, 95%CI =0.67-0.91, p=0.001). CD44v6 overexpression was also associated with more lymph node invasion (OR=1.48, 95%CI= 1.02-2.15, p=0.04), and advanced Dukes stage (OR=2.47, 95%CI= 1.29-4.73, p=0.01). In addition, while excluding Zolbec's study, CD44v6 overexpression was associated with distance metastasis (OR=1.65, 95%CI =1.13-2.40, p=0.01). Taken together, this meta-analysis suggested that CD44v6 is an efficient prognostic factor in colorectal cancer.

PARK14 PLA2G6 mutants are defective in preventing rotenone-induced mitochondrial dysfunction, ROS generation and activation of mitochondrial apoptotic pathway.

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.