RESUMEN
OBJECTIVES: Studies have extensively explored the role of microRNAs (miRs) in Parkinson's disease (PD) and miR-185 is related to autophagy and apoptosis of dopaminergic neurons in PD. However, the role of miR-185 mediating insulin-like growth factor 1 (IGF1)/phosphatidylinositol-3-kinase/protein kinase B signalling pathway (PI3K/AKT) in PD still needs in-depth exploration. METHODS: Rat PD models were established by injection of 6-hydroxydopamine. PD rats were injected with miR-185 or insulin-like growth factor 1 (IGF1)-related sequences. Behaviour tests were performed, oxidative stress-related factors, tyrosine hydroxylase (TH)-, glial fibrillary acidic protein (GFAP)-, ionised calcium-binding adaptor molecule-1 (Iba-1)- and TUNEL-positive cells in the substantia nigra were determined. Levels of miR-185, IGF1 and phosphatidylinositol-3-kinase/protein kinase B (PI3K/AKT) signalling pathway-related factors were also detected. RESULTS: miR-185 level was reduced in rats with PD. Restoring miR-185 promoted behaviour functions, ameliorated pathological damages and oxidative stress, increased TH-positive dopaminergic neurons, decreased GFAP- and Iba-1-positive cells and restrained neuronal apoptosis in the substantia nigra in PD rats. miR-185 targeted IGF1 to activate PI3K/AKT signalling pathway. Up-regulation of IGF1 mitigated restored miR-185-mediated effects on PD rats. CONCLUSION: This study illustrates that miR-185 ameliorates dopaminergic neuron damage via targeting IGF1 and activating PI3K/AKT signalling pathway in PD, which renews the therapy for PD.
Asunto(s)
Neuronas Dopaminérgicas/metabolismo , Factor I del Crecimiento Similar a la Insulina/genética , MicroARNs/genética , Enfermedad de Parkinson/genética , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/genética , Transducción de Señal/genética , Animales , Apoptosis/genética , Masculino , Estrés Oxidativo/genética , Ratas , Ratas Wistar , Sustancia Negra/metabolismo , Regulación hacia Arriba/genéticaRESUMEN
A reprogrammable transgenic mouse strain, called Col1a1 4F2A-Oct4-GFP, was bred for the present study. Because the somatic cells of this mouse strain contain only two copies of each Yamanaka factor, these animals are inefficient at producing induced pluripotent stem cells (iPSCs; approx. 0.005%) under traditional culture conditions. With an optimized culture condition, the iPSC production rate of mouse embryonic fibroblasts (MEFs) of Col1a1 4F2A-Oct4-GFP mice (MEFCol1a14F2A-Oct4-GFP ) was increased to approximately 8%. Further, promotion of cell proliferation by serum supplementation did not enhance iPSC production. Inhibition of transforming growth factor ß (TGF-ß) in the serum by SB431542 neither affected the growth rate of MEFCol1a14F2A-Oct4-GFP nor promoted iPSC production. However, the use of the gamma-irradiated STO-NEO-LIF (γSNL) cells to serve as feeders for iPSC production resulted in a 5-fold higher rate of iPSC production than the use of γMEFICR feeders. Interestingly, the use of SB431542 with the γMEFICR -adopted system could eliminate this difference. RT-PCR-based comparative analysis further demonstrated that TGF-ß expression was 10-fold higher in γMEFICR than in γSNL cells. Consistent with previous reports, mesenchymal to epithelial transition was found to participate in the initial steps of reprogramming in the specific context of MEFCol1a14F2A-Oct4-GFP . Moreover, we found that the initial seeding density is one of the pivotal factors for determining a high efficiency of iPSC generation. The iPSCs efficiently generated from our MEFCol1a14F2A-Oct4-GFP resembled mouse embryonic stem cells (mESCs) in aspects of teratoma formation and germline transmission. Depending on the culture conditions, our Col1a1 4F2A-Oct4-GFP mouse system can generate bona fide iPSCs with variable efficiencies, which can serve as a tool for interrogating the route taken by cells during somatic reprogramming.
Asunto(s)
Reprogramación Celular , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Factor de Crecimiento Transformador beta/fisiología , Animales , División Celular/efectos de los fármacos , Células Cultivadas , Técnicas de Cocultivo , Colágeno Tipo I/genética , Cadena alfa 1 del Colágeno Tipo I , Medios de Cultivo/farmacología , Doxiciclina/farmacología , Fibroblastos/fisiología , Fibroblastos/efectos de la radiación , Rayos gamma , Regulación de la Expresión Génica/efectos de los fármacos , Células Madre Pluripotentes Inducidas/citología , Ratones , Ratones Noqueados , Proteínas Recombinantes de Fusión/metabolismo , Teratoma/patología , Factores de Transcripción/farmacología , Factor de Crecimiento Transformador beta/farmacología , TransgenesRESUMEN
OBJECTIVE: To investigate the expression of human epidermal growth factor receptor 2 (HER-2/neu) in hepatocellular carcinoma (HCC) patients and its clinical significance. METHODS: The expressions of HER-2/neu were detected by SP immunohistochemistry method in 30 patients with HCC, 10 with portal cirrhosis of the liver and 10 with normal liver. RESULTS: The positivity rate of HER-2/neu was markedly higher in HCC patients than in those with portal cirrhosis and normal liver (Chi(2)=6.482, P=0.032). The expression of HER-2/neu was closely correlated to portal cirrhosis of the liver (P=0.041), tumor invasion (P=0.028) and Edmondson grades (P=0.012). The average survival time was significant shorter in patients with HER-2/neu-positive tumor than in those with HER-2/neu-negative tumor (P=0.036). CONCLUSION: The expression of HER-2/neu may play a role in the invasion, metastasis and progression of HCC. The patients positive for HER-2/neu in the HCC tissues have generally poor prognosis.