Biochemical and biophysical research communications
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Host RNA helicase has been involved in human immunodeficiency virus type 1 (HIV-1) replication, since HIV-1 does not encode an RNA helicase. Indeed, DDX1 and DDX3 DEAD-box RNA helicases are known to be required for efficient HIV-1 Rev-dependent RNA export. However, it remains unclear whether DDX RNA helicases modulate the HIV-1 Tat function. ⋯ Indeed, the ATPase-dependent RNA helicase activity of DDX3 seemed to be required for the Tat function as well as the colocalization with Tat. Furthermore, the combination of DDX3 with other distinct DDX RNA helicases cooperated to stimulate the Rev but not Tat function. Thus, DDX3 seems to interact with the HIV-1 Tat and facilitate the Tat function.
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Biochem. Biophys. Res. Commun. · Nov 2013
SPOCK1 is a novel transforming growth factor-β target gene that regulates lung cancer cell epithelial-mesenchymal transition.
Lung cancer is the leading cause of cancer related death worldwide and the prognosis is still poor with 5-year survival of approximately 15%. Metastasis is the leading cause of death by cancer. Recent researches have demonstrated that epithelial-to-mesenchymal transition (EMT) plays a key role in the early process of metastasis of cancer cells. ⋯ Interestingly, ectopic expression of SPOCK1 in epithelial lung cancer cells induced EMT with increased expression of the mesenchymal marker Vimentin and decreased expression of epithelial marker E-cadherin. We also found that the expression of SPOCK1 was increased under treatment of TGF-β, indicating that SPOCK1 is a novel downstream target of TGF-β. Taken together, our study showed that SPOCK1 is a novel metastasis related biomarker in lung cancer and may be new diagnostic and therapeutic target for lung cancer.
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Biochem. Biophys. Res. Commun. · Nov 2013
Acceleration of bone development and regeneration through the Wnt/β-catenin signaling pathway in mice heterozygously deficient for GSK-3β.
Glycogen synthase kinase (GSK)-3β plays an important role in osteoblastogenesis by regulating the Wnt/β-catenin signaling pathway. Therefore, we investigated whether GSK-3β deficiency affects bone development and regeneration using mice heterozygously deficient for GSK-3β (GSK-3β(+/-)). The amounts of β-catenin, c-Myc, cyclin D1, and runt-related transcription factor-2 (Runx2) in the bone marrow cells of GSK-3β(+/-) mice were significantly increased compared with those of wild-type mice, indicating that Wnt/β-catenin signals were enhanced in GSK-3β(+/-) mice. ⋯ Subsequently, to investigate the effect of GSK-3β deficiency on bone regeneration, we established a partial bone defect in the femur and observed new bone at 14 days after surgery. The volume and mineral density of the new bone were significantly higher in GSK-3β(+/-) mice than those in wild-type mice. These results suggest that bone formation and regeneration in vivo are accelerated by inhibition of GSK-3β, probably through activation of the Wnt/β-catenin signaling pathway.
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Biochem. Biophys. Res. Commun. · Nov 2013
Geraniol attenuates α-synuclein expression and neuromuscular impairment through increase dopamine content in MPTP intoxicated mice by dose dependent manner.
Parkinson's disease (PD) is characterized by progressive loss of dopamine (DA) neurons in the nigrostriatal system and by the presence of Lewy bodies (LB), proteinaceous inclusions mainly composed of filamentous α-synuclein (α-Syn) aggregates. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was adopted to generate PD models in C57BL/6 mice. In the present study, we investigated the effect of geraniol (GE) against α-Syn aggregation on MPTP induced mouse model of PD in dose dependant manner. ⋯ In addition, we confirmed that sub-chronic administration of MPTP in mice leads to permanent neuromuscular deficits and depletion of dopamine and its metabolites. Our results suggest that GE is beneficial for the treatment of PD associated with neuromuscular disability and LB aggregation.