ABSTRACT
Objective@#To screen lentiviral vectors carrying siRNA which can specifically down-regulate the gene expression of the sphingosine-1-phosphate receptor 3 (S1PR3) in the corpus cavernosum smooth muscle (CCSM) cells of rats with spontaneous hypertension (SHT) and investigate the influence of the vectors on the signaling pathways of ROCK1, ROCK2 and eNOS in the CCSM cells of SHT rats.@*METHODS@#Using the S1PR3 mRNA sequence of the rat as an interfering target, we designed and synthesized three pairs of siRNA sequences (siRNA1, 2 and 3) targeting S1PR3 and one pair of negative control, and then constructed and packaged them into lentiviral vectors. We cultured the CCSM cells of SHT and Wistar-Kyoto (WKY) rats in vitro and randomly divided them into groups A (SHT untransfected control), B (SHT transfected and carrying negative control virus), C (SHT transfected and carrying siRNA1 targeting S1PR3), D (SHT transfected and carrying siRNA2 targeting S1PR3), E (SHT transfected and carrying siRNA3 targeting S1PR3), and F (WKY untransfected control). With the multiplicity of infection (MOI) = 60, we transfected the CCSM cells of the SHT rats with the lentiviral vector and then determined the expression of the green fluorescent protein (GFP) as well as the mRNA and protein expressions of S1PR3, ROCK1, ROCK2 and eNOS in the CCSM cells of the SHT and WKY rats by RT-PCR and Western blot.@*RESULTS@#Gene sequencing proved the successful construction of the lentiviral vector. The transfection efficiency of the CCSM cells of the rats was >80% in groups B, C, D and E. Compared with group A, the mRNA and protein expressions of S1PR3, ROCK1 and ROCK2 exhibited no significant difference in group B but were remarkably decreased in groups C, D, E and F (P0.05) but remarkably lower than those in group F (P0.05) but markedly increased in groups A, B, C and D (P< 0.05), while those of eNOS remarkably decreased in groups A, B, C, D and E (P< 0.05).@*CONCLUSIONS@#The three constructed lentiviral vectors carrying siRNA targeting different loci of the S1PR3 gene could significantly inhibit the expression of S1P3 as well as RhoA/Rho kinase signaling pathways in the CCSM cells of SHT rats, and the vector carrying siRNA3 exhibited the highest inhibitory effect.
Subject(s)
Animals , Male , Rats , Down-Regulation , Gene Expression , Genetic Vectors , Green Fluorescent Proteins , Metabolism , Lentivirus , Genetics , Myocytes, Smooth Muscle , Metabolism , Nitric Oxide Synthase Type III , Metabolism , Penis , Metabolism , RNA, Messenger , RNA, Small Interfering , Genetics , Metabolism , Random Allocation , Rats, Inbred WKY , Receptors, Lysosphingolipid , Genetics , Metabolism , Signal Transduction , Sphingosine-1-Phosphate Receptors , Transfection , rho-Associated Kinases , MetabolismABSTRACT
<p><b>Objective</b>To investigate the effect of salidroside on the expression of the connexin43 (Cx43) protein in the corpus cavernosum smooth muscle cells (CCSMCs) of hypoxic SD rats.</p><p><b>METHODS</b>CCSMCs were cultured in vitro and identified by immunofluorescence staining. The cells were divided into six groups: normal control (21% O2), hypoxia (1% O2), hypoxia+salidroside (HS) 8 μg/ml,HS 16 μg/ml, HS 32 μg/ml, and HS 64 μg/ml, and cultured for 48 hours. Then the relative expression of Cx43 in different groups was detected by Western blot.</p><p><b>RESULTS</b>The in vitro cultured CCSMCs grew well and 90% of the cells showed positivity for α-SMA and desmin on immunohistochemistry. Salidroside ≤64 μg/ml produced no obvious toxicity on the CCSMCs. The expressions of Cx43 and phosphorylated proteins were dramatically increased in the hypoxia group as compared with the normal control (P<0.01 and P<0.05). The HS groups all showed significantly higher expression of Cx43 than the hypoxia group (P<0.01), but the phosphorylation rate of the Cx43 proteins was remarkably decreased (P<0.01).</p><p><b>CONCLUSIONS</b>Hypoxia increases the expression of Cx43 in the CCSMCs of SD rats. Salidroside ≤64 μg/ml cannot reverse the hypoxia-induced change but can reduce the dephosphorylation of Cx43 in CCSMCs. It is deduced that salidroside can protect CCSMCs by decreasing the phosphorylation of Cx43 and suppressing hypoxia-induced formation of the gap junction channel.</p>
Subject(s)
Animals , Male , Rats , Actins , Metabolism , Cell Hypoxia , Cells, Cultured , Connexin 43 , Metabolism , Glucosides , Pharmacology , Myocytes, Smooth Muscle , Metabolism , Penis , Metabolism , Phenols , Pharmacology , Phosphorylation , Rats, Sprague-DawleyABSTRACT
The correlation between hypoxia and erectile dysfunction (ED) has been universally acknowledged for decades in the academic world. The phenotypic modulation of corpus cavernosum smooth muscle cells (CCSMCs) is regarded as one of the factors of hypoxia-induced ED, but the underlying mechanisms remain unclear. Recent researches show some correlation between autophagy and phenotypic modulation of CCSMCs, which may be associated with the overexpressions of PDGF, TGF-β, and vasoactive factors in the organism following hypoxia.