The E3 ubiquitin ligase seven in absentia homolog 1 may be a potential new therapeutic target for Parkinson's disease.

In this study, we investigated the effect of an antibody against E3 ubiquitin ligase seven in absentia homolog 1 (SIAH-1) in PC12 cells. 1-Methyl-4-phenylpyridinium (MPP(+)) treatment increased α-synuclein, E1 and SIAH-1 protein levels in PC12 cells, and it reduced cell viability; however, there was no significant change in light chain 3 expression. Treatment with an SIAH-1 antibody decreased mRNA expression levels of α-synuclein, light chain 3 and SIAH-1, but increased E1 mRNA expression. It also increased cell viability. Combined treatment with MPP(+) and rapamycin reduced SIAH-1 and α-synuclein levels. Treatment with SIAH-1 antibody alone diminished α-synuclein immunoreactivity in PC12 cells, and reduced the colocalization of α-synuclein and light chain 3. These findings suggest that the SIAH-1 antibody reduces the monoubiquitination and aggregation of α-synuclein, promoting its degradation by the ubiquitin-proteasome pathway. Consequently, SIAH-1 may be a potential new therapeutic target for Parkinson's disease.

Silencing of SIAH1 in SH-SY5Y affects α-synuclein degradation pathway.

Seven in absentia homolog (SIAH) is a ubiquitin ligase that monoubiquitinates α-synuclein. Lewy bodies are characteristically rich in monoubiquitinated α-synuclein. We aimed to determine the effect of siRNA-SIAH1 on α-synuclein autophagy and UPS degradation in SH-SY5Y. SIAH1 expression was measured with real-time quantitative PCR and Western Blot. Cell proliferation was measured by CCK-8 assay; cell apoptosis assayed by flow cytometry. Relative protein expressions were measured by Western Blot. mRNA levels of relative protein were measured by real-time quantitative PCR. The expression of α-synuclein, LC3-II and SIAH1 were observed by confocal microscopy. We found: (1) Transfection efficiency of SIAH1-siRNA into SH-SY5 measured approximately 89% by flow cytometry. (2) siRNA silencing of SIAH1 promoted cellular proliferation and suppressed apoptosis. (3) Protein and mRNA expression of α-synuclein, LC3-II and p53 decreased after SIAH1 knockdown. E1 protein and mRNA levels increased after SIAH1 siRNA. These data show silencing SIAH1 increased cell proliferation and inhibited apoptosis in SH-SY5Y neuroblastoma cells. SIAH1 knockdown enhanced the clearance of non-aggregated α-synuclein by UPS. SIAH1 is a potential target for treatment of Parkinson's disease.

The effects of kangxianling on renal fibrosis as assessed with a customized gene chip.

OBJECTIVE: To determine the mechanisms by which kangxianling (KXL) treats renal interstitial fibrosis using a customized gene chip. METHODS: Twelve out of 18 specific pathogen-free sprague dawley (SPF SD) rats underwent a unilateral ureteral occlusion. These rats were then randomly assigned into either the model unilateral ureteral obstruction (UUO) or kangxianling (KXL) group. The other six rats were assigned to the sham-operated group. The UUO and sham-operated groups were given normal saline via intragastric administration, whereas the KXL group was given KXL via intragastric administration. All rats were sacrificed for renal tissue collection (i.e., left nephridial tissue), and the detection of genetic changes with the customized chip. RESULTS: Compared to the sham-operated group, transforming growth factor-beta (TGF-beta), Smad2, and Smad3 genes were significantly up-regulated in the UUO group, with >1.5-fold rise (P < 0.01). The Smad7 gene was significantly reduced in the UUO versus sham-operated group, with a down-regulation of >1.5-fold (P < 0.01). In the KXL group, TGF-beta1, Smad2, and Smad3 genes were significantly reduced compared to the UUO group, with a down-regulation of >1.5-fold (P < 0.01), whereas the Smad7 gene was significantly increased compared to the UUO group, with an up-regulation of > 1.5-fold (P < 0.01). CONCLUSION: It was found that KXL can significantly reduce the gene levels of TGF-beta1, Smad2, and Smad3. Immunohistochemistry findings also revealed significantly lower TGF-beta1/Smads-mediated gene transcription activity. These findings suggest that KXL may negatively regulate the TGF-beta1/Smads signal pathway to inhibit the occurrence of renal fibrosis.

[GTW-induced abnormal expressions of testicular reproduction-related genes and intervention with kidney-tonifying Chinese herbs].

OBJECTIVE: To explore the abnormal expressions of testicular reproduction-related genes induced by glycosides of Tripterygium wilfordii (GTW) and the intervention with kidney-tonifying Chinese herbs. METHODS: Adult Balb/C male mice were fed on GTW at 30 mg per kg per d for 3 weeks to establish a model of reproductive dysfunction. The model mice were divided into different groups to receive intragastrical administration of saline (0.25 ml/d), GTW (30 mg per kg per d), Cistanche (10 g per kg per d), Rehmannia (10 g per kg per d), and Rehmannia + Cistanche (20 g per kg per d), respectively, once a day for 3 weeks. And a Cistanches pretreatment group was treated with GTW (30 mg per kg per d) and Cistanche (10 g per kg per d) for the same length of time. Then we detected the changed expressions of testicular reproduction-related genes Dzip1, Fas, c-jun and Wnt4 in each group. RESULTS: The model mice showed an obviously down-regulated expression of the Y chromosome microdeletion-related gene Dzip1, and up-regulated expressions of the germ cell apoptosis-related gene Fas, proto-oncogene c-jun, and signal transduction-related gene Wnt4. Intervention with Chinese herbs achieved different degrees of improvement of the mice's reproductivity, and the most obvious efficacy was observed with the combined use of kidney-yang tonifying Cistanche and kidney-yin nourishing Rehmannia. CONCLUSION: GTW exerts significant impact on reproduction-related genes. Both the kidney-yang tonifying drug Cistanche and kidney-yin nourishing drug Rehmannia can counteract some of the reproductive toxicity of GTW, while the combination of the two can further enhance the effect.