Regulation of palmitic acid and lipopolysaccharide-induced macrophage polarization by adipokine WNT1-inducible signaling pathway protein 2 / 中华老年医学杂志

Objective:To investigate the regulatory effect of WNT1-inducible signaling pathway protein 2(WISP2)on macrophage polarization in palmitic acid(PA)and lipopolysaccharide(LPS)-induced inflammation.Methods:The macrophage cell line RAW264.7 was treated with different concentrations of WISP2 protein, and cell viability was determined by means of luminescence assay using Cell-Titer Glo to determine the concentration of WISP2.The cells were divided into control group, palmitic acid group, palmitic acid combined with different concentrations of WISP2 group(10 μg/L and 100 μg/L)and lipopolysaccharide group, lipopolysaccharide combined with different concentrations of WISP2 group(10 μg/L and 100 μg/L). mRNA expression of M1 and M2 macrophages phenotype of each group were detected by real-time quantitative polymerase chain reaction.The protein expression of important inflammatory factors, TNF-α and IL-6, were evaluated by ELISA.Results:Compared with the control group, both 10 μg/L and 100 μg/L WISP2 groups had no effect on the activity of RAW264.7 cells, but significantly up-regulated the expression of various inflammatory factors, including Tnfα(1.877±0.039, 2.202±0.034, F=309.7, P<0.001), Il6(1.418±0.056, 1.506±0.059, F=81.39, P<0.001), Mcp1(1.620±0.014, 1.982±0.125, F=71.45, P<0.001), Ccl3(1.892±0.118, 1.942±0.132, F=32.93, P<0.001), and iNos(1.691±0.201, 1.548±0.090, F=13.60, P<0.05). mRNA in macrophages, and significantly down-regulated the expression of anti-inflammatory factors, including Tgfβ(1.376±0.025, 2.152±0.107, F=1.846, P<0.05), CD206(2.123±0.031, 3.139±1.663, F=8.037, P<0.05), Il4(2.098±0.464, 2.494±0.141, F=48.68, P<0.01), and Il10(1.303±0.216, 1.574±0.274, F=5.774, P<0.05)mRNA, causing M1 type macrophage polarization.Compared with the control group, 100 μmol/L palmitic acid could mildly but significantly increase the expression of inflammatory factors such as TNF-α and IL-6 at the transcriptional and protein levels.Compared with palmitic acid stimulation alone, the combination of palmitic acid and WISP2 further promoted the protein expression of macrophage inflammatory factors TNF-α[(589.4±17.0)ng/L, (692.6±83.4)ng/L, F=56.38, P<0.05], IL-6[(15.13±1.14)ng/L, (13.33±1.22)ng/L, F=23.32, P<0.001]and the mRNA expression of chemokines Mcp1(160±9.796, 140±18.91, F=141.1, P<0.0001)and C cl3(17.76±1.92, 14.41±1.27, F=125.2, P<0.0001). Compared with the control group, 100 μg/L lipopolysaccharide strongly stimulated the expression of inflammatory factors such as TNF-α[(3444±423)ng/L, F=71.20, P<0.0001]and IL-6[(497.0±41.2)ng/L, F=63.50, P<0.0001]in macrophages at the protein level.Compared with lipopolysaccharide stimulation alone, the combination of lipopolysaccharide and WISP2 further significantly up-regulated the mRNA expression of chemokines Mcp1(106.8±8.7, 118.7±4.6, F=251.5, P<0.0001)and Ccl3(35.3±12.5, 116.4±4.5, F=160.1, P<0.0001). Conclusions:The adipokine WISP2 can promote M1 macrophage polarization in palmitic acid and lipopolysaccharide-induced inflammation, and it had distinct regulation in macrophage polarization under different inflammatory response conditions.

The effects of WNT1 inducible signaling pathway protein 2 on hepatocyte lipid metabolism and associated mechanisms / 中华老年医学杂志

Objective:To investigate the effects of various concentrations of recombinant human WISP2 protein(WISP2)on lipid metabolism in HepG2 cells.Methods:HepG2 cells were treated with different concentrations(0, 0.4, 1 and 2 μg/L)of recombinant human WISP2 for 48 hours.Cell viability was detected by Cell-Titer, and enzymatic hydrolysis methods were used to measure intracellular triacylglycerol(TG)and total cholesterol(TC)levels.The mRNA expression was detected by quantitative real-time reverse transcription-PCR(RT-qPCR)and protein expression in HepG2 cells was detected by western blot.Results:Compared with the control group, the WISP2 groups treated with various concentration did not significantly reduce the viability of HepG2 cells.TG and TC in HepG2 cells were significantly increased by recombinant human WISP2 treatment(all P<0.05).The concentrations of TG in the 0.4, 1 and 2 μg/L recombinant human WISP2-treated groups were 1.254±0.039, 1.216±0.028 and 1.174±0.014)times the concentration in the untreated group, respectively( F=6.791, P=0.006).The concentration of TC in the untreated group was 1.264±0.057, 1.394±0.101 and 1.392±0.077), respectively, times the concentration in each of the treated groups( F=7.045, P=0.005).Further experiments found that the mRNA expression of sterol regulatory element binding protein 1(SREBP1), 3-hydroxy-3-methylglutaryl coenzyme A reductase(HMGCR), acetyl-CoA carboxylase(ACC), type 2 diacylglycerol acyltransferase(DGAT2)and the protein expression of SREBP1, ACC and fatty acid synthase(FAS)were significantly increased in the recombinant human WISP2-treated groups, compared with the control group(all P<0.05).However, the expression of lipid transporters such as the low-density lipoprotein receptor(LDLR), ApoB and ApoE and adipose triglyceride lipase(ATGL), a key lipolysis protein, was not significantly affected. Conclusions:Human recombinant WISP2 protein increases lipid levels in hepatocytes and the key underlying mechanisms may be through promoting lipid synthesis.

Effects of resveratrol on high-fat diet-induced hypertrophic obesity in elderly mice / 中华老年医学杂志

Objective:To investigate the effects and potential mechanisms of resveratrol on obesity in elderly mice.Methods:In this study, 3 groups were randomly formed for 32-week-old mice and for 48-week-old mice.The normal diet group received regular chow and 0.3 ml saline by gavage once a day, the high-fat diet group received a high-fat diet(containing 21% fat and 1.25% cholesterol)and 0.3 ml saline once a day, and the high-fat diet plus resveratrol group received a high-fat diet and resveratrol(22.4 mg/kg, dispersed in 0.3 ml saline)by gavage once a day.After 12 weeks, body weight and adipose tissues were measured.Plasma leptin concentrations were determined by an enzyme-linked immunosorbent assay(ELISA), and values for hypertrophic obesity-related indexes of mice were obtained by quantitative real-time PCR.Results:The body weight and the proportion of subcutaneous fat tissues were lower in the high-fat diet plus resveratrol group than in the high-fat diet group[(34.43±3.23)g vs.(53.16±2.16)g, (3.21±1.58)% vs.(4.86±0.64)%, P<0.01], and were similar to those in the normal diet group.Resveratrol had a more obvious inhibitory effect on leptin in elderly mice than in middle-aged mice.In elderly mice, the plasma leptin concentration was lower in the high-fat diet plus resveratrol group than in the high-fat diet group[(0.015±0.009)g/L vs.(0.100±0.027)g/L]and the normal diet group( F=19.85, P=0.001), and it was similar to that in the middle-aged mice on a normal diet.Resveratrol significantly increased the expression of peroxisome proliferator-activated receptor gamma(PPARγ)and glucose transporter 4(GLUT4)and reduced the expression of tumor necrosis factor-α(TNF-α)( F=10.79, 9.31 and 7.02, P=0.003, 0.006 and 0.010). Conclusions:Resveratrol can significantly improve hypertrophic obesity in elderly mice, and the inhibition of leptin secretion and up-regulation of PPARγ may be the key mechanisms.

Lithium chloride inhibits vascular smooth muscle cell calcification by increasing pyrophosphate levels / 中华老年医学杂志

Objective:To investigate the effects of lithium chloride on vascular smooth muscle cell calcification and the potential underlying mechanisms.Methods:Human aortic smooth muscle cells were cultured in vitro, and a smooth muscle cell calcification model was established by using a calcification medium(the concentration of inorganic phosphorus was 3 mmol/L). Cells in the drug treatment group were pretreated with lithium chloride(10 mmol/L)for 4 hours and then with inorganic phosphorus at 3 mmol/L.After several days in culture, calcium deposition in cells was measured by alizarin red S staining.The secretion of extracellular pyrophosphate was detected by measuring nicotinamide adenine dinucleotide hydrogen(NADH) consumption of pyrophosphate-coupled enzyme reactions, which were monitored spectrophotometrically at 340 nm.Real-time PCR and Western blotting were used to detect mRNA and protein expression of the human progressive ankylosis( ankh)gene.Human aortic smooth muscle cells were infected with the scramble control lentivirus and the sh- ankh lentivirus, respectively, to establish the control cell group and the ankh knockdown cell group.The effects of ankh knockdown on cell calcification were examined. Results:The calcification level in vascular smooth muscle cells increased in the high inorganic phosphorus group, compared with the control group[(65.00±2.11)ng/g vs.(12.39±0.38)ng/g, P<0.01)]. Compared with the high-phosphorus control group, lithium chloride evidently inhibited high phosphate-induced vascular smooth muscle cell calcification[(24.92±1.87)ng/g vs.(60.94±4.51)ng/g, P<0.01)]. Lithium chloride pretreatment clearly increased extracellular pyrophosphate levels under unstimulated conditions[(51.70±7.26)×10 -3mmol/g vs.(28.71±2.55)×10 -3mmol/g( P<0.01)]and under high phosphorus stimulation[(34.35±4.27)×10 -3mmol/g vs.(20.89±4.93)×10 -3mmol/g( P<0.05)], and increased the expression of ankh as well( P<0.01). In addition, ankh knockdown markedly enhanced the extent of inorganic phosphorus-induced vascular smooth muscle cell calcification(71.73±2.45 ng/g vs.56.19±3.59 ng/g, P<0.01). Conclusions:Lithium chloride inhibits high phosphorus-induced vascular smooth muscle cell calcification by enhancing the level of extracellular pyrophosphate via increased ankh expression.

Ginkgolide B inhibits apoptosis in high glucose-stimulated human umbilical vein endothelial cells / 中国药理学通报

Aim Toinvestigatetheeffectofginkgolide B on apoptosis in high glucose-treated endothelial cells.Methods Humanumbilicalveinendothelial cells(HUVECs)were used in the present study.The level of transmigration of HUVECs was analyzed by Tr-answell experiment.Apoptosis was detected by flow cy-tometry.Reactive Oxygen Species (ROS ) was meas-ured by immunofluorescence kit.The protein expres-sionwasanalyzedbyWesternblot.Result Highglu-cose treatment resulted in a reduction in transmigration of HUVECs and ginkgolide B recovered the phenome-non in glucose-treated endothelial cells.The level of ROS generation was increased in high glucose-treated group,whereas ginkgolide B inhibited ROS genera-tion.Immunofluorescence data showed high glucose in-creased apoptosis,whereas ginkgolide B inhibited ap-optosis in high glucose-treated HUVECs.Moreover, the expressions of Bax and caspase-3 were increased and Bcl-2 was reduced in high glucose-treated group. In contrast,ginkgolide B abolished the expressions of Bax and caspase-3 and increased Bcl-2 expression. Moreover,high glucose enhanced the expression and phosphorylation of p53,while ginkgolide B suppressed the expression and phosphorylation of p53 induced by highglucose.Conclusions GinkgolideBcaninhibit apoptosis and improve transmigration function in high glucose-treated HUVECs.Ginkgolide B has protection against high glucose-induced endothelial cell injury.

Effect of resveratrol on ROS production and PECAM-1 expression in ox-LDL-stimulated platelets / 中国药理学通报

Aim To investigate the effect of resveratrol on ROS level and PECAM-1 expression in ox-LDL-stimulated platelets. Methods The expression of PE-CAM-1 , Sirt1 and p38 MAPK phosphorylation in ox-LDL-stimulated platelets was determined by Western blot. The level of ROS was measured by immunofluo-rescence kit. Results ox-LDL induced platelet aggre-gation by 14%, whereas resveratrol inhibited platelet aggregation by 50%. Resveratrol decreased ROS level by 3 . 2 fold and completely suppressed PECAM-1 expression in ox-LDL-treated platelets. Resveratrol re-covered Sirt1 expression in ox-LDL-treated platelets. EX527 ( a Sirt1 inhibitor ) increased ROS level and PECAM-1 expression in ox-LDL-stimulated platelets. Meanwhile, resveratrol also suppressed p38MAPK phosphorylation induced by ox-LDL. Conclusion Resveratrol can inhibit platelet aggregation, decrease ROS production and PECAM-1 expression in ox-LDL-stimulated platelets. The mechanism maybe associated with recovery of Sirt1 expression. Moreover, resveratrol can decrease PECAM-1 expression, which may be linked to abolishing p38MAPK phosphorylation.

Effect of ginkgolide B on TLR4 and inflammatory protein expression in high glucose treated human umbilical vein endothelial cells / 中国药理学通报

Aim To investigate the effect of ginkgolide B on TLR4 expression in glucose-treated endothelial cells.Methods Human umbilical vein endothelial cells (HUVECs)were stimulated by high concentra-tion of glucose.TLR4,inflammatory protein expression and Akt phosphorylation were analyzed by Western blot.Transcription factor NF-κB nuclear translocation was analyzed by immunofluorescence.Results The expression of TLR4 and PAF receptor was increased in high glucose-treated HUVECs. In contrast, both ginkgolide B and CV3988 dose-dependently decreased TLR4 and PAF receptor expression in high glucose-treated cells,respectively.Ginkgolide B decreased in-flammatory protein ICAM-1 ,VCAM-1 expression.Mo-reover,ginkgolide B potently abolished Akt phospho-rylation and NF-κB p65 nuclear translocation.Conclu-sion Ginkgolide B can reduce TLR4,PAF receptor, ICAM-1 and VCAM-1 expression in high dose of glu-cose-treated HUVECs,the mechanism might be linked to inhibition of Akt phosphorylation and NF-κB activa-tion.

Effect of ginkgolide B on junctional proteins in oxidized LDL-stimulated human umbilical vein endothelial cells / 中国药理学通报

Aim To investigate the effect of ginkgolide B on junctional proteins in ox-LDL-stimulated human umbilical vein endothelial cells ( HUVECs) . Methods After incubation with ginkgolide B ( 0 . 2 ,0 . 4 ,0 . 6 g · L-1 ) for 1 h, HUVECs were treated with ox-LDL (0. 1 g·L-1 ) for 4 h. The expressions of JAM-A and Cx43 were analyzed with Western blot and immunofluo-rescence. The effect of ginkgolide B on vascular per-meability was analyzed by Transwell experiments. Re-sults JAM-A and Cx43 expressions increased by 22%and 24% in ox-LDL-treated HUVECs, respectively. Whereas ginkgolide B significantly decreased JAM-A and Cx43 expressions. LY294002, a specific inhibitor of PI3K, suppressed JAM-A and Cx43 expressions in ox-LDL-stimulated cells. Ginkgolide B potently re-duced monocyte migration in ox-LDL-treated cells. Conclusion Ginkgolide B significantly suppresses JAM-A and Cx43 expressions, and reduces monocyte migration in ox-LDL-stimulated cells. This demon-strates that ginkgolide B can improve vascular permea-bility. The mechanism might be associated with the in-hibition of PI3K/Akt signaling pathway.

Thioredoxin inhibits human vascular endothelial cell adhesion molecules expression via Smad3/AP-1 pathway / 中华老年医学杂志

Objective To investigate the molecular mechanisms of protective effects of thioredoxin (Trx) on human vascular endothelial cells in atherosclerosis.Methods The cell models of Trx-overexpressing cells (Ad Trx) and the control cells (Ad-con) were established by adenovirus vector gene transfer technology in human umbilical vein endothelial cells (HUVECs).The oxidized low density lipoprotein,a risk factor of atherosclerosis,was used as a stimulator.Western blot and indirect immunofluorescence were used to detect the protein expression levels and the cellular localization of Trx,adhesion molecules (ICAM-1,VCAM-1) and the upstream signal pathways.Trx activity was detected by insulin disulfide reduction assay,and cellular reactive oxygen species (ROS)production was detected by fluorescent probe DCFH-DA.Results As compared with control group,Trx protein expression level was enhanced in Ad-trx group and the Trx activity in Ad-Trx group was upregulated by (26.2 ±3.3)％.The result of ROS detection showed that overexpression of Trx significantly inhibited the cellular ROS generation.As compared with control group,overexpression of Trx obviously inhibited the adhesion molecules expression but markedly promoted the phosphorylation of Smad3 in endothelial cells with or without oxLDL stimulation (P＜0.05).Pretreatment of cells with SIS3,a specific inhibitor of Smad3 phosphorylation,reversed Trx-induced inhibition of adhesion molecules expression.Further studies showed that pretreatment of cells with SIS3 enhanced oxLDL-induced AP-1 subunit c-fos nuclear expression.Conclusions The enhancement of Smad3 phosphorylation and c-Fos nuclear expression are mainly responsible for the Trx-induced downregulation of adhesion molecules.