Detection of Exogenous γ-Hydroxybutyric Acid in Rat Blood Exosomes / 法医学杂志

OBJECTIVES@#To find a method to distinguish exogenous gamma-hydroxybutyrate (GHB) from endogenous GHB by establishing ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS) based on exosome for quantitative detection of GHB in the rat blood.@*METHODS@#Adult male SD rats were divided into 1 h, 5 h, 10 h administration group and control group. After 1 h, 5 h and 10 h of single precursor of GHB gamma-butyrolactone (GBL) intraperitoneal injection in administration groups, 5 mL blood was collected from the abdominal aorta. Meanwhile, the control group was given a same dose of normal saline, and 5 mL blood was collected at 1 h. Among the 5 mL blood, 0.5 mL was directly detected by HPLC-MS after pretreatment, and exosomes were extracted from the remaining blood by differential centrifugation and detected.@*RESULTS@#The concentration of GHB in the control group was (87.36±33.48) ng/mL, and the concentration with administration at 1 h, 5 h and 10 h was (110 400.00±1 766.35) ng/mL, (1 479.00±687.01) ng/mL and (133.60±12.17) ng/mL, respectively. The results of exosome detection showed that no peak GHB signal was detected in the control group and the 10 h administration group, and the concentrations of GHB at 1 h and 5 h administration groups were (91.47±33.44) ng/mL and (49.43±7.05) ng/mL, respectively.@*CONCLUSIONS@#GHB was detected in blood exosome by UPLC-MS, which indicated that exogenous GHB could be detected in plasma exosomes, while endogenous GHB could not be detected, suggesting that this method may be used as a basis to determine whether there is exogenous drug intake.

Effect of spleen tyrosine kinase on the proliferation of pulmonary vascular smooth muscle cells in rats / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the role of spleen tyrosine kinase (Syk) in rat pulmonary vascular smooth muscle cells (PVSMCs) proliferation induced by platelet-derived growth factor-BB (PDGF-BB).</p><p><b>METHODS</b>PVSMCs from male Sprague-Dawley rats were cultured in vitro and the cells of passages 3-5 were used in the experiment. PVSMCs were stimulated by PDGF-BB and were treated with three different doses of piceatannol, a Syk selective inhibitor. Cell proliferation was assessed by methyl thiazolyl tetrazolium (MTT) assay. DNA synthesis was measured by ³H-thymidine incorporation (³H-TdR). Cellular cycle was observed by flow cytometry. Syk mRNA and protein expression were detected using real-time quantitative PCR and Western blot, respectively.</p><p><b>RESULTS</b>The expression of Syk protein of PVSMCs was significantly up-regulated following PDGF-BB stimulation. PDGF-BB stimulation dramatically increased PVSMCs proliferation. After piceatannol treatment, both Syk mRNA and protein expression decreased and the proliferation of PVSMCs was inhibited in a dose-dependent manner.</p><p><b>CONCLUSIONS</b>Syk may promote PVSMCs proliferation induced by PDGF-BB.</p>

Effects of endogenous carbon monoxide on gene expression profiles associated with the apoptosis of pulmonary arterial smooth muscle cells / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To identify the gene expression profiles associated with the apoptosis of pulmonary arterial smooth muscle cells stimulated by carbon monoxide (CO).</p><p><b>METHODS</b>Primary cultured Sprague-Dawley rat pulmonary arterial smooth muscle cells (PASMC) were stimulated by platelet-derived growth factor (PDGF, 20 ng/mL) and hemin (20 μmol/L). Cells were harvested after 2 hrs and Affymetrix microarrays were used to detect the gene expression profile.</p><p><b>RESULTS</b>Some genes associated with Map2k3 (P38) signal pathway, such as CyclinD1, CyclinH, CyclinL1, MAP2K3, Kras and Nras, were upregulated, but P27 expression was downregulated after PDGF treatment. After endogenous CO treatment, some genes associated with P53 pathway, such as Gadd45α, P21 and Trp53inp1, were upregulated.</p><p><b>CONCLUSIONS</b>P53 pathway probably plays an important role in apoptosis of pulmonary arterial smooth muscle cells treated with endogenous CO.</p>

Role of spleen tyrosine kinase in phenotypic modulation of vascular smooth muscle cell induced by platelet-derived growth factor-BB / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate the role of spleen tyrosine kinase (syk) in the phenotypic modulation induced by platelet-derived growth factor (PDGF-BB) in rat pulmonary vascular smooth muscle cells (VSMC).</p><p><b>METHODS</b>Vascular smooth muscles were isolated from pulmonary media of SD rats, cultured, adopted, and divided into 3 groups: blank control group, control group and medicine intervention group. The changes of proliferation and ultrastructure of vascular smooth muscle cells by using [(3)H] thymidine incorporation and electron microscopy. The mRNA and protein expression level of syk, alpha-smooth muscle-actin (α-SM-actin) and smooth muscle protein 22alpha (SM22α) were detected by RT-PCR and Western blotting. The change of fluorescence intensity was detected by laser scanning confocal microscope.</p><p><b>RESULTS</b>Treatment with PDGF-BB for 24 h resulted in a significant increase in [(3)H] thymidine incorporation (2429.25 ± 253.36 vs. 242.75 ± 14.33,P < 0.01) and marked change in phenotype and cytoskeleton, the level of average optical density decreased significantly (263.75 ± 19.21 vs.1146.23 ± 62.61, P < 0.01). Meanwhile, the mRNA (1.70 ± 0.25 vs. 1.01 ± 0.12, P < 0.05) and protein level of syk significantly increased, the mRNA and protein expression of α-SM-actin (0.10 ± 0.00 vs. 1.00 ± 0.00, P < 0.01) and SM22α (0.18 ± 0.00 vs. 1.00 ± 0.01, P < 0.01) significantly decreased in VSMC induced by PDGF-BB. Piceatannol could inhibit significantly these biological effects. Compared with control group, the level of [(3)H] thymidine incorporation (527.00 ± 27.76 vs. 2429.25 ± 253.36,P < 0.01) was significantly down-regulated and the VSMC presented an apoptotic status in medicine intervention group, the level of average optical density increased significantly (810.65 ± 37.94 vs. 263.75 ± 19.21,P < 0.01) in medicine intervention group. Meanwhile, the mRNA (0.36 ± 0.07 vs. 1.70 ± 0.25, P < 0.01) and protein level of syk significantly decreased. The mRNA and protein levels of α-SM-actin (0.22 ± 0.00 vs. 0.10 ± 0.00, P < 0.01) and SM22α (0.31 ± 0.00 vs. 0.18 ± 0.00, P < 0.01) were significantly higher in medicine intervention group than in control group. The level of average optical density increased significantly (810.65 ± 37.94 vs. 263.75 ± 19.21, P < 0.01).</p><p><b>CONCLUSION</b>Syk plays an important role in vascular remodeling by changing the phenotypes and cytoskeleton of VSMC stimulated by PDGF-BB.</p>