ABSTRACT
ObjectiveTo investigate the expression of phosphoinositide 3-kinase (PI3K), mammalian target of rapamycin (mTOR), 70-kDa ribosomal protein S6 kinase (p70S6K), and interferon-α (IFNα) in umbilical cord blood plasmacytoid dendritic cells (pDCs) in parturients in the immune tolerance stage of hepatitis B virus (HBV) infection versus normal parturients. MethodsA total of 20 parturients in the immune tolerance stage of HBV infection and 10 normal parturients who were hospitalized in Inpatient Department of Obstetrics in The First Affiliated Hospital of Hunan University of Chinese Medicine from October 2017 to January 2020 were enrolled as hepatitis B group and normal group, respectively. Umbilical cord blood pDCs were isolated and cultured, and CpG-A was added on day 7. The cells and the supernatant were collected after 24 hours; real-time PCR was used to measure the mRNA expression of PI3K, mTOR, and p70S6K, Western Blot was used to measure the protein expression of PI3K, mTOR, and p70S6K, and ELISA was used to measure the level of IFNα in the supernatant of pDCs. The two-independent-samples t-test was used for comparison of continuous data between the two groups. ResultsCompared with the normal group, the hepatitis B group had significantly lower mRNA and protein expression of PI3K, mTOR, and p70S6K in umbilical cord blood pDCs (mRNA expression: t=-81.04, -63.07, and -34.55, all P＜0.001; protein expression: t=-8.13, -7.75, and -6.71, all P＜0.001). The hepatitis B group had significantly lower expression of IFNα in the supernatant of umbilical cord blood pDCs than the normal group (t=-15.88, P＜0.05). ConclusionParturients in the immune tolerance stage of HBV infection have reductions in the mRNA and protein expression of PI3K, mTOR, and p70S6K and the level of IFNα in umbilical cord blood pDCs, suggesting that pDC function is inhibited.
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Objective To investigate the effects of 1,25-dihydroxyvitamin D3[1,25 (OH)2D3] on cell proliferation in hu?man glomerular mesangial cells and it′s effects on the regulation of mTOR/p70s6K signaling pathway in this cell line. Meth?ods The cultured human mesangial cells at passage 3-7 were divided into four groups:control group,VD group (addition of 10-8 mol/L of 1,25-dihydroxyvitamin D3 ),R group (addition of 5 mg/L of rapamycin) and R+VD group(addition of 5 mg/L ra?pamycin combined with 10-8 mol/L of 1,25-dihydroxyvitamin D3). Drug incubation last 48 h. The effect of mesangial cell pro?liferation was measured by CCK-8 colorimetric assay. The cell cycles were measured by flow cytometry. The expression of mTOR and p70s6K were detected by immunofluorescence. Results (1) The absorbance of A450 was higher in control group than that in VD group than that in R group than that in R+VD group. But the inhibition rate (IR) was lower in control group than that in VD group than that in R group than that in R+VD group. All comparisons were of statistic significance. ( 2) Cells in G1 phase were higher while cells in G2/M and S phases as well as proliferation rate (PI) were lower in control group than those in VD group than those in R group than those in R+VD group. All comparisons were of statistic significance except in?dexes between group R and group VD. (3) mTOR and p30s6K expressions in mesangial cells were higher in control group than those in VD group than those in R group than those in R+VD group. All comparisons were of statistic significance ex?cept indexes between group R and group VD. Conclusion 1,25-dihydroxyvitamin D3 might inhibit mesangial cell prolifera?tion significantly through mTOR/p70s6K signaling pathways.
ABSTRACT
Phosphoinositide 3-kinase (PI3K)/protein kinase-B (AkT)/mammalian target of rapamycin (mTOR)/70-kDa ribosomal protein S6 kinase (p70S6K), PI3K/Akt/mTOR/p70S6K, is an important signaling pathway in the life activities of cells, and it plays an important role in promoting the growth, proliferation, invasion, and anti-apoptosis of cells and promoting angiogenesis. It was clarified that the PI3K/Akt/mTOR/p70S6K signaling pathway is involved in regulating the activities of hepatic stellate cell(HSC), thus influencing the development and progression of hepatic fibrosis. Analysis demonstrated that blocking any target of the PI3K/Akt/mTOR/p70S6K signaling pathway can inhibit the activation and proliferation of HSC, promote the apoptosis of HSC, inhibit the extracellular matrix secretion from HSC, and delay the progression of hepatic fibrosis. Blocking the pathway is expected to be a treatment strategy for hepatic fibrosis.
ABSTRACT
Objective To evaluate the effects of sevoflurane postconditioning on the expression of 70 kD aribosomalprotein S6 kinase (p70S6K) during ischemia-reperfusion (I/R) in isolated rat hearts.Methods Pathogen-free male Sprague-Dawley rats,aged 3 months,weighing 270-350 g,were used in the study.Their hearts were excised and perfused in a Langendorff apparatus with K-H solution saturated with 95 ％ O2-5 ％ CO2.Ninety isolated rat hearts with I/R injury were randomly divided into 3 groups (n =30 each):sham operation group (group S),I/R group (group I/R),and sevoflurane postconditioning group (group SP).The hearts were subjected to ischemia for 30 min followed by 2 h reperfusion.In group SP,the hearts were perfused with K-H solution saturated with 3.0％ sevoflurane for 15 min starting from the end of ischemia until 15 min of reperfusion,and then with plain K-H solution for 105 min.At 2 h of reperfusion,myocardial infarct size was measured,the percentage of myocardial infarct size was calculated,and the phosphorylated p70S6K (p-p70S6K)/total p70S6K (tp70S6K) ratio,and cytoplasm,cytochrome C,and caspase-8 expression was measured.Results Compared with group S,the percentage of myocardial infarct size and p-p70S6K/t-p70S6K ratio were significantly increased,the expression of cytochrome C,and caspase-8 was up-regulated,and the expression of cytochrome C was downregulated in I/R group.Compared with I/R group,the percentage of myocardial infarct size was significantly decreased,the ratio of p-p70S6K/t-p70S6K was increased and cytochrome C expression was up-regulated,and the expression of cytochrome C and caspase-8 was down-regulated in SP group.Conclusion Sevoflurane postconditioning can mitigate I/R injury to isolated rat hearts,and up-regulation of p-p70S6K expression,inhibition of transfer of cytochrome C from mitochondria to cytoplasm,and reduced cell apoptosis are involved in the mechanism.