We identified three heterozygous nonsynonymous single nucleotide polymorphisms in the small heterodimer partner (SHP, NROB2) gene in normal subjects and CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy)-like patients, including two novel missense mutations (p.R38H, p.K170N) and one of the previously reported polymorphism (p.G171A). Four novel heterozygous mutations were also identified in the intron ( Intron 1265T3 A), 3-untranslated region ( 3-UTR 101C3 G, 3-UTR 186T3 C), and promoter ( Pro -423C3 T) of the SHP gene. The exonic R38H and K170N mutants exhibited impaired nuclear translocation. K170N made SHP more susceptible to ubiquitination mediated degradation and blocked SHP acetylation, which displayed lost repressive activity on its interacting partners ERR␥ and HNF4␣ but not LRH-1. In contrast, G171A increased SHP mRNA and protein expression and maintained normal function. In general, the interaction of SHP mutants with LRH-1 and EID1 was enhanced. K170N also markedly impaired the recruitment of SHP, HNF4␣, HDAC1, and HDAC3 to the apoCIII promoter. Molecular dynamics simulations of SHP showed that G171A stabilized the nuclear receptor boxes, whereas K170N promoted the conformational destabilization of all the structural elements of the receptor. This study suggests that genetic variations in SHP are common among human subjects and the Lys-170 residue plays a key role in controlling SHP ubiquitination and acetylation associated with SHP protein stability and repressive function.

Grade IV glioblastoma multiforme (GBM) is the most malignant form of gliomas. HSP47, encoded by SERPINH1 gene, is a serpin which serves as a human chaperone protein for collagen. We have shown that HSP47 is significantly overexpressed in GBM and associated with tumor grade. However, the role of HSP47 on GBM progression and stemlike property remains unclear. The stable overexpression of HSP47 in primary GBM cells was established by lentivirus infection. The effects of HSP47 overexpression on tumor growth and the effects of blocking the TGF-β pathway on tumor regression were investigated by animal study. The expression of HSP47 was examined by real time qRT-PCR and immunohistochemistry. The stemlike property was investigated by sphere formation and CD44 cell population analysis using flow cytometry. We found that overexpression of HSP47 promotes primary glioma cell tumor formation, invasion, angiogenesis, and stemlike properties. The overexpression of HSP47 was correlated and promoted extracellular matrix (ECM) related genes through the TGF-β pathway in GBM. Blocking TGF-β pathway overcomes HSP47 induced tumorigenesis and stemness. This study demonstrated that HSP47 promotes GBM stemlike cell survival by modulating tumor microenvironment ECM through TGF-β pathway. Blocking the TGF-β pathway provides a promising therapeutic potential for HSP47 overexpressed GBM.

Brain-derived neurotrophic factor (BDNF) provides neuroprotective effects towards therapeutic cerebral ischemia-reperfusion (I/R) injury. This view has been proposed by more and more evidence. However, due to the lack of permeability of the blood-brain barrier (BBB) as well as the brief half-life in serum, clinical application is not widespread. To study the participation of exosomes containing BDNF in I/R, we isolated exosomes from BDNF-overexpressing HEK293. The protective outcomes of exosomes in hypoxia/reoxygenation (H/R) experiments were determined by the use of SY-5Y cells. Exosome-BDNF therapy restrained H/R-induced apoptosis by inhibition of the reducing levels of oxidative stress and calcium ions in the cells while maintaining stable levels of mitochondrial membrane potential in brain cells damaged by I/R. We then constructed a cerebral I/R injury model using SD rats to find the function of BDNF in exosome-mediated neuroprotection. The in vivo experiments conducted established that exosomes from BDNF-overexpressing HEK293 cells improved cerebral I/R injury by concealing neuronal apoptosis. Findings gained demonstrated that BDNF is a part of preventing cerebral I/R injury due to exosome mediation by regulating the cellular internal environment and inhibiting apoptosis.