Bioinformatic analysis of a microRNA regulatory network in Huntington's disease.

Huntington's disease is an autosomal dominant hereditary neurodegenerative disease characterized by progressive dystonia, chorea and cognitive or psychiatric disturbances. The leading cause is the Huntington gene mutation on the patient's chromosome 4 that produces a mutated protein. Recently, attention has focused on the relationship between microRNAs and Huntington's disease's pathogenesis. In Huntington's disease, microRNAs can interact with various transcription factors; dysregulated microRNAs may be associated with the Cytosine deoxynucleotide-Adenine ribonucleotides-Guanine ribonucleotide length and Huntington's disease's progression and severity. This study explores the role of microRNAs in the pathogenesis of Huntington's disease through bioinformatics analysis. By analyzing data from the Gene Expression Omnibus database, we identified a total of 9 differentially expressed microRNA. Subsequently, target genes and long non-coding RNAs were predicted, and a comprehensive regulatory network centered on microRNA was constructed. The microRNA integrated regulatory network, Homo sapiens (hsa)-miR-144-3p, interacted with the largest number of long non-coding RNAs, including X-inactive specific transcript and taurine upregulated gene 1. The miRNAs, hsa-miR-10b-5p and hsa-miR-196a-5p, regulated most of the target genes, including class I homeobox and brain-derived neurotrophic factor genes. Additionally, 59 Gene Ontology terms and eight enrichment pathways were identified by analyzing the target genes of hsa-miR-196a-5p and hsa-microRNA-10b-5p. In conclusion, hsa-miR-10b-5p and hsa-miR-196a-5p were significantly and differentially expressed in Huntington's disease, the long non-coding RNAs X-inactive specific transcript, taurine upregulated gene 1, and target genes such as homeobox or brain-derived neurotrophic factor may play critical roles in the pathogenesis of Huntington's disease.

Histone acetyltransferase MOF is involved in suppression of endometrial cancer and maintenance of ERα stability.

Histone acetyltransferase MOF is involved in active transcription regulation through histone H4K16 acetylation. MOF is downexpressed in a number of human tumors, but biological function of MOF in endometrial cancer has not been fully defined. The estrogen receptor α (ERα) is a transcription factor that regulates estrogen-stimulated cell proliferation in hormone-responsive tumors. However, ERα expression is decreased in grade III ECa samples and high expression of ERα is associated with long disease-free survival in ECa. The molecular mechanism for these observations is still unclear. Here we demonstrate knockdown of MOF promotes ECa cell growth and proliferation in vitro and in vivo. Clinical evidence indicates that expression MOF is decreased and positively correlated with that of ERα in ECa tissues. Furthermore, MOF physically interacts with ERα and modulates ERα stability in ECa cells. In addition, MOF modulates expression of a subset of endogenous genes regulated by ERα. Taken together, our results define MOF as a potential tumor suppressor in ECa participates in maintenance of ERα protein stability and regulation of ERα action.

Association of E-selectin gene polymorphisms with ischemic stroke in a Chinese Han population.

The E-selectin gene, a member of the selectin superfamily of adhesion molecules, plays an important role in the pathogenesis of thrombovascular diseases. The present study was designed to investigate the potential relationship between E-selectin gene polymorphisms and ischemic stroke in a Chinese Han population. Three hundred fourteen ischemic stroke patients and 389 unrelated healthy controls were recruited for the study. Three single-nucleotide polymorphisms (SNPs)-rs1805193(G98T), rs5361(A561C), and rs5355(C1839T)-in the exon region of the E-selectin gene, were genotyped using a Multiplex SNaPshot sequencing assay. The data showed that the genotype and allele frequencies of G98T and C1839T SNP were similar in both ischemic stroke patients and the controls. In contrast, the frequency of both the AC genotype and the C allele of A561C was significantly higher in ischemic stroke patients than in healthy controls (P = 0.001, P < 0.001, respectively). After adjusting for other risk factors (such as hypertension, diabetes, tobacco smoking, and alcohol consumption), the E-selectin gene AC genotype and C allele of A561C were still associated with a risk of ischemic stroke (odds ratio [OR] = 2.73, 95% confidence interval (CI): 1.29-5.76, P = 0.008; OR = 2.80, 95% CI: 1.58-4.94, P < 0.001, respectively). Our current study demonstrates that the E-selectin SNP A561C is associated with increased risk for the development of ischemic stroke in this subset of the Han Chinese population.

[Clinical and imaging features of hemorrhagic stroke during pregnancy and puerperium].

OBJECTIVE: To investigate the clinical and imaging features of hemorrhagic stroke during pregnancy and puerperium (HSPP). METHODS: A retrospective analysis was conducted about timing, precipitating factors, clinical manifestations, imaging characteristics, treatment and outcome of 7 HSPP patients. RESULTS: None of 7 HSPP occurred in the first trimester, 3 in the second trimester, 2 in the third trimester and 2 in the puerperium. Three of 4 patients whose etiology was due to ruptured arteriovenous malformations (AVM) occurred in the second trimester, including one case in the puerperium. Two patients had been diagnosed as cerebral vascular AVM before pregnancy. One patient had eclampsia during pregnancy. The initial symptoms and signs of 7 patients: 4 cases with headache, nausea and vomiting, 4 cases with extremity paralysis, 3 cases with disorders of consciousness, 4 cases with aphasia, 2 cases with central face and tongue paralysis and 1 case with extremity numbness. Cerebral imaging investigations showed 2 cases with basilar ganglia hemorrhage, 4 cases with lobar hemorrhage and 1 case with subarachnoid hemorrhage (SAH). There were 4 cases whose etiology was because of ruptured AVM. Two of 7 patients were treated with operation, 2 with endovascular intervention and 3 with conservative treatment. The prognosis included full recovery (1/7), marked improvement (4/7), slight improvement (1/7) and death (1/7). CONCLUSION: The onset time of HSPP concentrated in the second, third trimester and the puerperium; Onset time of the patients because of ruptured AVM concentrated in the second trimester. Cerebral imaging examination could elucidate the nature of lesion and the etiology of disease.

Efficacy and tolerability of pramipexole for the treatment of primary restless leg syndrome: a meta-analysis of randomized placebo-controlled trials.

Primary restless leg syndrome (RLS) is a common sensory-motor disorder that is characterized by an irresistible urge to move the limbs and unpleasant sensations in the legs, which affects 1.9%-4.6% adults. Pramipexole, a potent dopamine D2/3 agonist, is recommended as "effective" in the short-term and "possibly effective" in the long-term treatment of primary RLS in the European guidelines on management of RLS. In this meta-analysis, we summarized the efficacy and tolerability of pramipexole in treatment for primary RLS. Results of this meta-analysis showed a favorable effect of pramipexole versus placebo on RLS symptoms (mean change on International RLS Study Group Rating Scale [IRLS] score: mean difference [MD] = -5.96; 95% confidence interval [CI]: -7.79 to -4.41, P < 0.00001) and sleep quality (pooled standard mean difference [SMD] = -0.48, 95% CI: -0.61 to -0.35, P < 0.00001). Nausea (relative risk [RR] = 2.68, 95% CI: 1.82 to 3.95, P < 0.001) and fatigue (RR = 1.82, 95% CI: 1.14 to 2.93, P = 0.013) were the most common adverse events, but, by and large, pramipexole was well-tolerated in patients with primary RLS. Nevertheless, long-term studies and more evidence of head-to-head comparisons of pramipexole with other dopamine agonists, anticonvulsants, and levodopa are needed.

Small N-terminal mutant huntingtin fragments, but not wild type, are mainly present in monomeric form: Implications for pathogenesis.

N-terminal fragments of huntingtin containing an expanded polyglutamine stretch play an important role in the molecular pathogenesis of Huntington's disease. Their ultimate accumulation in insoluble protein aggregates constitutes an important pathological hallmark of Huntington's disease. We report on systematic biochemical comparison studies of soluble wild type and mutant N-terminal huntingtin fragments. The results show that soluble wild type exon 1 fragments are predominantly present in higher molecular weight complexes with a molecular size of approximately 300 kDa, while their mutant counterparts are mainly present in their monomeric form. In contrast, longer N-terminal fragments corresponding to peptides produced by caspase cleavage do not display these differential properties. These findings suggest that especially an increased amount of monomeric form of small N-terminal mutant huntingtin fragments may facilitate aberrant interactions both with itself via the polyglutamine stretch and with other proteins and thereby contribute to molecular pathogenesis.

Epitope mapping of monoclonal antibody 4C8 recognizing the protein huntingtin.

Huntington's disease is a dominantly inherited, devastating neurodegenerative disorder, caused by a polyglutamine expansion (>37) in the N-terminal region of huntingtin, a protein of unknown function. In patients and normal individuals, N-terminal fragments of huntingtin are found, and the N-terminal fragments of mutant huntingtin are cytotoxic. The functions of wild-type huntingtin and the mechanisms underlying the toxic effects of mutant huntingtin are still ill defined. To get more insight into these topics, monoclonal antibodies (MAbs) are indispensable tools. Antibodies raised against the N-terminus are especially important. Among these, the 4C8 mouse MAb has been extensively used in various approaches. In this study, we have mapped the epitope of 4C8 to a 15-amino acid (aa) region spanning from aa 443 to 457 of the human protein, and found that mutation of three consecutive glutamic acids present in this region disrupts the recognition by 4C8. These results allow a more accurate interpretation of the results obtained by usage of the 4C8 antibody and broaden the utility of this antibody.

Mutant huntingtin represses CBP, but not p300, by binding and protein degradation.

Huntington's disease can be used as a model to study neurodegenerative disorders caused by aggregation-prone proteins. It has been proposed that the entrapment of transcription factors in aggregates plays an important role in pathogenesis. We now report that the transcriptional activity of CBP is already repressed in the early time points by soluble mutant huntingtin, whereas the histone acetylase activity of CBP/p300 is gradually diminished over time. Mutant huntingtin bound much stronger to CBP than normal huntingtin, possibly contributing to repression. Especially at the later time points, CBP protein level was gradually reduced via the proteasome pathway. In sharp contrast, p300 was unaffected by mutant huntingtin. This selective degradation of CBP was absent in spinocerebellar ataxia 3. Thus, mutant huntingtin specifically affects CBP and not p300 both at the early and later time points, via multiple mechanisms. In addition to the reduction of CBP, also the altered ratio of these closely related histone acetyl transferases may affect chromatin structure and transcription and thus contribute to neurodegeneration.

Mutant huntingtin represses CBP, but not p300, by binding and protein degradation.

Huntington's disease can be used as a model to study neurodegenerative disorders caused by aggregation-prone proteins. It has been proposed that the entrapment of transcription factors in aggregates plays an important role in pathogenesis. We now report that the transcriptional activity of CBP is already repressed in the early time points by soluble mutant huntingtin, whereas the histone acetylase activity of CBP/p300 is gradually diminished over time. Mutant huntingtin bound much stronger to CBP than normal huntingtin, possibly contributing to repression. Especially at the later time points, CBP protein level was gradually reduced via the proteasome pathway. In sharp contrast, p300 was unaffected by mutant huntingtin. This selective degradation of CBP was absent in spinocerebellar ataxia 3. Thus, mutant huntingtin specifically affects CBP and not p300 both at the early and later time points, via multiple mechanisms. In addition to the reduction of CBP, also the altered ratio of these closely related histone acetyltransferases may affect chromatin structure and transcription and thus contribute to neurodegeneration.