HOTAIRM1 knockdown reduces MPP+-induced oxidative stress injury of SH-SY5Y cells by activating the Nrf2/HO-1 pathway.

Objective: Parkinson's disease (PD) is the second most common neurodegenerative disease with complex pathogenesis. Although HOXA transcript antisense RNA myeloid-specific 1 (HOTAIRM1) is upregulated in PD, its exact role in HOTAIRM1 is seldom reported. The purpose of this study is to research the effect of HOTAIRM1 on 1-methyl-4-phenylpyridonium (MPP+)-induced cytotoxicity and oxidative stress in SH-SY5Y cells. Methods: SH-SY5Y cells were treated with MPP+ at various concentrations or time points to induce SH-SY5Y cytotoxicity, so as to determine the optimal MPP+ concentration and time point. HOTAIRM1 expression upon MPP+ treatment was analyzed through qRT-PCR. Next, HOTAIRM1 was downregulated to observe the variance of SH-SY5Y cell viability, apoptosis, oxidative stress-related indexes, and protein levels of the Nrf2/HO-1 pathway. In addition, rescue experiments were carried out to assess the role of Nrf2 silencing in HOTAIRM1 knockdown on MPP+-induced oxidative stress in SH-SY5Y cells. Results: MPP+ treatment-induced cytotoxicity and upregulated HOTAIRM1 expression in SH-SY5Y cells in a dose- and time-dependent manner. Mechanically, HOTAIRM1 knockdown enhanced cell viability, limited apoptosis, and oxidative stress, therefore protecting SH-SY5Y cells from MPP+-induced SH-SY5Y cytotoxicity. On the other hand, HOTAIRM1 knockdown activated the protein levels of Nrf2 and HO-1. Nrf2 silencing could counteract the neuroprotective effect of HOTAIRM1 knockdown on in vitro PD model. Conclusion: Our data demonstrated that HOTAIRM1 knockdown could inhibit apoptosis and oxidative stress and activated the Nrf2/HO-1 pathway, therefore exerting neuroprotective effect on the PD cell model.

Astaxanthin suppresses endoplasmic reticulum stress and protects against neuron damage in Parkinson's disease by regulating miR-7/SNCA axis.

Parkinson's disease (PD) is a common neurodegenerative disorder that featured by the loss of dopaminergic neurons. Astaxanthin (AST), an important antioxidant, is demonstrated to be a neuroprotective agent for PD. However, the underlying mechanisms of AST in PD remain largely unclear. In this study, we found that AST treatment significantly not only abolished the cell viability inhibition and apoptosis promotion induced by 1-methyl-4-phenylpyridinium (MPP+) in SH-SY5Y cells via inhibiting endoplasmic reticulum (ER) stress, but also reversed the MPP+ caused dysregulation of miR-7 and SNCA expression. MiR-7 knockdown and SNCA overexpression were achieved by treating SH-SY5Y cells with miR-7 inhibitor and pcDNA3.1-SNCA plasmids, respectively. MiR-7 could bind to and negatively regulate SNCA in SH-SY5Y cells. Treated SH-SY5Y cells with miR-7 inhibitor or pcDNA3.1-SNCA abrogated the protective effects of AST on MPP+ induced cytotoxicity. Knockdown of miR-7 aggravated 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induced neuron injury in vivo suggested by athletic performance, histopathological morphology, expression of tyrosine hydroxylase (TH) and TUNEL positvie cells, however, AST treatment could reverse these effects of miR-7 knockdown. Collectively, AST suppressed ER stress and protected against PD-caused neuron damage by targeting miR-7/SNCA axis, implying that AST might be a potential effective therapeutic agent for PD.

[Mutation analysis of pathogenic genes in a Henan family affected with congenital stationary night blindness].

OBJECTIVE: To detect genetic mutations associated with autosomal dominant congenital stationary night blindness (ADCSNB) in a family from Henan province. METHODS: Genomic DNA was extracted from peripheral blood samples of 14 family members. Based on 3 genes reported previously, PCR primers were designed and corresponding exons containing the mutation sites were amplified with PCR. PCR products were purified and directly sequenced. RESULTS: A c.281C>T heterozygous missense mutation was detected in RHO gene in all of the patients. This mutation can cause a change of the protein structure (p.Thr94Ile). The same mutation was not detected in normal individuals from the family and 50 normal controls. CONCLUSION: A c.281C>T mutation in RHO gene is responsible for the onset of ADCSNB in this Chinese family and results in symptoms of night blindness.

[Mutation analysis of the pathogenic gene in a Chinese family with Brachydactyly type B1].

We identified and characterized a Chinese family with autosomal dominant Brachydactyly type B1 (BDB1). Linkage analysis revealed that the disease gene of the Chinese BDB1 family was linked to ROR2 locus. Mutational hot spot of ROR2 gene was amplified by polymerase chain reaction (PCR) and sequenced directly. A c.2265C>A heterozygous mutation was detected in all of the patients. This mutation led to the change of p.Y755X in protein level and a truncated ROR2 protein losing integrant domains was generated. The mutation was detected in all the patients, but not in all the normal individuals of this family and 50 normal controls. This paper for the first time reported a c.2265C>A mutation in ROR2 gene of a family with BDB1 in China, which enriches ROR2 gene mutation spectrum in Chinese with BDB1.