Effect of kappa elastin on melanogenesis in A375 human melanoma cells and its related mechanism / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Elastin derived peptides can regulate melanocyte precursor development. Ultraviolet irradiation, infrared radiation and heat can increase the synthesis of tropoelastin in human skin epidermis. The aim of this study was to investigate whether the over expressed tropoelastin in epidermis has some role in melanogenesis of melanocytes.</p><p><b>METHODS</b>A375 human melanoma cells were treated with different concentrations of kappa elastin for 24 hours. A375 human melanoma cells were randomly assigned to control, kappa elastin, and lactose pre-incubated groups. The cell viabilities were detected by the methyl thiazoleterazolium assay. Melanin content and tyrosinase activity in A375 melanoma cells were measured. The expressions of endothelin B receptor (ET(B)R) mRNA and c-kit mRNA in A375 melanoma cells were measured by quantative reverse transcription polymerase chain reaction.</p><p><b>RESULTS</b>Fifty µg/ml of kappa elastin significantly increased the melanin content by 56.64% compared with the control (P < 0.05). Kappa elastin increased cellular tyrosinase activity by 46.73% compared with the control at 24 hours (P < 0.05). Kappa elastin increased the expressions of ET(B)R and c-kit mRNA levels by 2.13-fold and 2.47-fold compared with the controls, respectively. When pre-incubating cells with a lactose solution (10 mmol/L), the inhibition on melanin production was 34.96% compared with the kappa elastin group (P < 0.05), tyrosinase activity was inhibited by 29.93% compared with kappa elastin group (P < 0.05), and the expressions of ET(B)R mRNA and c-kit mRNA were decreased by 1.56-fold and 0.82-fold compared with kappa elastin group, respectively.</p><p><b>CONCLUSION</b>Kappa elastin increased the melanogenesis in A375 melanoma cells via the stimulation of tyrosinase activity and the expression of ET(B)R and c-kit. The over expressed tropoelastin produced by keratinocytes might play a role in melanogenesis of epidermal melanocytes.</p>

Quercetin in combating H2O2 induced early cell apoptosis and mitochondrial damage to normal human keratinocytes / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Oxidative stress plays an important role in the pathogenesis of epidermal diseases. This study aimed to investigate the effects of quercetin on the anti-oxidative response and on mitochondrial protection in cultured normal human keratinocytes.</p><p><b>METHODS</b>Cultured HaCaT cells were treated with different concentrations of H2O2 (0, 50, 100, 250, 500 micromol/L) for different periods of time (0.5, 1, 2, 4 hours) to establish an oxidative stress model. The cultured HaCaT cells were randomly assigned to control, H2O2, and quercetin + H2O2 groups. For the quercetin groups, the cells were treated with different concentrations of quercetin (0, 10, 25, 50 micromol/L) before exposure to H2O2. Morphological changes of the cells were observed under an inverted microscope and an electron microscope. The cell viability was detected by the MTT method. The cell apoptosis (AnnexinV/propidium iodide double stain) and mitochondrial membrane potential (DeltaPsim) changes were detected by flow cytometry.</p><p><b>RESULTS</b>An oxidative stress model of HaCaT cells was established under a suitable concentration (250 micromol/L) and treated time of H2O2 (2 hours). The cell viability and DeltaPsim decreased in a concentration-dependent and time-dependent manner while the percentage of apoptotic cells significantly increased in the H2O2 groups compared with the control group (P < 0.05). The cell viability and DeltaPsim of the quercetin treated group increased (P < 0.05) and the percentage of apoptotic cells decreased at concentrations of 1-50 micromol/L quercetin (P < 0.01) compared with H2O2 treated group.</p><p><b>CONCLUSION</b>Quercetin can relieve the cell damage and apoptosis from H2O2 induced injury to HaCaT cells by anti-oxidation and mitochondrial protection.</p>

Phosphodiesterase type 5 siRNA increases cGMP in the smooth muscle cells of human corpus cavernosum / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the effect of phosphodiesterase type 5 (PDE5) small interfering RNA (siRNA) on the cGMP in the smooth muscle cells of human corpus cavernosum, and to provide an experimental groundwork for the gene therapy of erectile dysfunction (ED).</p><p><b>METHODS</b>Small interfering RNAs targeting PDE5 gene were synthesized by using web design software provided by Ambion, three siRNAs and a control siRNA were synthesized by Ambion. siRNAs were transfected into the smooth muscle cells of human corpus cavernosum by using siPORT Lipid reagent. cGMP was detected by ELISA at different times (24, 48, 72 and 96 h) after transfection.</p><p><b>RESULTS</b>The cGMP levels of the siRNA1, siRNA2 and siRNA3 groups were significantly higher than those of the siRNA control and blank control groups (P < 0.05), and so was it in the siRNA1 group than the siRNA2 and siRNA3 groups (P < 0.05), with significant difference between the siRNA control and the blank control group (P > 0.05).</p><p><b>CONCLUSION</b>The synthesized siRNAs in vitro are capable of increasing the level of cGMP in the smooth muscle cells of human corpus cavernosum, different siRNAs with different capabilities. The siRNA technique could provide not only an extremely powerful tool for the functional analysis of genome but also a new approach to ED gene therapy.</p>

The effects of antisenes oligodeoxynucleotide on the cyclic nucleotide monophosphates in smooth muscle cells of human corpus cavernosum / 中华男科学杂志

<p><b>OBJECTIVES</b>To investigate the effects of antisense oligodeoxynucleotide(ASON) on the cyclic nucleotide monophosphates (cNMP) in smooth muscle cells of human corpus cavernosum, and provide experimental groundwork for the gene therapy of erectile dysfunction.</p><p><b>METHODS</b>PDE5 gene ASON(containing exon 1) was transfected into the corpus cavernosum smooth muscle cells with the presence of liposome DOTAP. Another sense oligodeoxynucleotide(SON) and 1% of bovine serum were also transducted into the cells as controls. Two of cNMP, cAMP and cGMP, were probed and measured by ELISA at 1, 2, 4, 6, 10, 24 and 48 h after transfection.</p><p><b>RESULTS</b>After transfection, the level of cGMP(1-6 h) in human corpus cavernosum smooth muscle cells was significantly higher than that in controls(P < 0.01).</p><p><b>CONCLUSIONS</b>The PDE5 gene ASON had been showed to manifest stimulative effect on the cGMP in smooth muscle cells of human corpus cavernosum in vitro, and it provides experimental groundwork for the gene therapy of erectile dysfunction.</p>