Research progress on autophagy-related protein 5 and BECLIN-1 regulate autophagy and apoptosis / 中国人兽共患病学报

ATG5 and BECLIN-1 belong to two kind of crucial autophagy-related proteins included the formation of autoph-agosomes,in addition to the promotion of autophagy,enhances susceptibility towards apoptotic stimuli,therefore,ATG5 and BECLIN-1 are considered to be a molecular link between autophagy and apoptosis.Preliminary data revealed that ATG5 media-ted the formation of autophagosomes by ATG5-ATG12-ATG16L ubiquitination system,while BECLIN-1 induces autophagy by phosphatidylino3-kinase (PtdIns3KC3)complex.But now it is believed that truncated ATG5(tATG5-N)and truncated BEC-LIN-1(BECLIN-1-C),an amino-terminal cleavage product of ATG5 and carboxyl-terminal cleavage product of BECLIN-1, could induce apoptosis.The research summarize the progress on ATG5 and BECLIN-1 regulated autophagy and apoptosis,so as to further reveal the molecular mechanism of they regulate autophagy and apoptosis.

Effects of high glucose on expression of OPG and RANKL in rat aortic vascular smooth muscle cells

OBJECTIVE@#To explore effect of high glucose on expression of osteoprotegerin (OPG) and receptor activator of NF- κ B ligand (RANKE) in rat aortic vascular smooth muscle cells.@*METHODS@#SD rats were intraperitoneally injected with streptozotocin, OPG and RANKL expression in rat thoracic aortas were detected by immunohistochemical staining. In cultured vascular smooth muscle cells (VSMCs) (A7r5), qRT-PCR and Western blot analysis were used to examine the mRNA and protein levels of OPG and RANKL.@*RESULTS@#Our results demonstrated that OPG expression was increased in hyperglycemic rat aortic VSMCs, while RANKL expression was decreased. Besides, in vitro experiments high glucose induced OPG expression, but depressed RANKL expression by dose- and time-dependent manner in cultured A7r5.@*CONCLUSIONS@#Our findings suggested that high glucose could promote the expression of OPG, and inhibit the expression of RANKL in VSMCs, which may be partly be the molecular mechanism of diabetic vascular calcification.

Effects of high glucose on expression of OPG and RANKL in rat aortic vascular smooth muscle cells

Objective: To explore effect of high glucose on expression of osteoprotegerin (OPG) and receptor activator of NF- κ B ligand (RANKE) in rat aortic vascular smooth muscle cells. Methods: SD rats were intraperitoneally injected with streptozotocin, OPG and RANKL expression in rat thoracic aortas were detected by immunohistochemical staining. In cultured vascular smooth muscle cells (VSMCs) (A7r5), qRT-PCR and Western blot analysis were used to examine the mRNA and protein levels of OPG and RANKL. Results: Our results demonstrated that OPG expression was increased in hyperglycemic rat aortic VSMCs, while RANKL expression was decreased. Besides, in vitro experiments high glucose induced OPG expression, but depressed RANKL expression by dose- and time-dependent manner in cultured A7r5. Conclusions: Our findings suggested that high glucose could promote the expression of OPG, and inhibit the expression of RANKL in VSMCs, which may be partly be the molecular mechanism of diabetic vascular calcification.

Association of interleukin-1β genetic polymorphisms with obstructive sleep apnea syndrome / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the association between interleukin (IL)-1β genetic polymorphisms and obstructive sleep apnea syndrome (OSAS).</p><p><b>METHODS</b>Totally 850 individuals with hypertension were included. All of them were checked by polysomnography in the Hypertension Center of People's Hospital of Xinjiang Uygur Autonomous Region from January to December in 2010. According to the results of polysomnography, these subjects were divided into non-OSAS group (n=225)and OSAS group (n=625). Genetic variations were sequenced and screened at loci over functional region of IL-1β gene in 96 patients with severe OSAS.The typical loci were selected for genotyping by TaqMan-polymerase chain reaction in 850 subjects.</p><p><b>RESULTS</b>One novel and 5 known variations in the IL-1β gene were identified, and then three representative mutation loci were selected for genotyping.The allele frequency distribution of rs1143633 was significantly different between the OSAS and non-OSAS groups in the total and male populations (χ(2)=9.258, P=0.002;χ(2)=5.119, P=0.024, respectively). Although the parameters of sleep apnea monitoring showed no significant difference in individuals with CC, CT, and TT genotypes of rs1143633 in total, male, and female populations (P>0.05), the median of the apnea hypopnea index of CT genotype was significantly higher than that of CC and TT in total and male populations and the mean of the lowest blood oxygen saturation increased in individuals with CC, CT, and TT genotypes of rs1143633 in total and male populations.Haplotype was no significantly associated with OSAS in total,male,and female populations(P>0.05).Logistic regression analysis showed that CT genotype of rs1143633 variation was a risk factor for OSAS in total and male populations (OR=1.574,95% CI=1.061-2.437,P=0.042;OR=1.887,95% CI=1.091- 3.265,P=0.023).</p><p><b>CONCLUSION</b>The rs1143633 polymorphism in IL-1β gene may be associated with OSAS.</p>

Association of glucose transporter 4 gene polymorphism with hypoxia caused by obstructive sleep apnea syndrome and with related inflammatory factors / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the relationship between genetic polymorphisms of glucose transporter 4 (GLUT4) and hypoxia caused by obstructive sleep apnea syndrome (OSAS) as well as with related inflammatory factors.</p><p><b>METHODS</b>Consecutive hypertension patients diagnosed at the People's Hospital of Xinjiang Uygur Autonomous Region were selected from January to December 2010. A total of 859 subjects with possible OSAS base on their histories and physical examination findings udner went the polysomnography and inflammatory factor determination, of whom 616 (72%) were diagnosed with moderate and severe hypoxia with OSAS (case group) and 243 (28%) without hypoxia or OASA (control group). Ninty-six patients from the case group underwent DNA sequencing at the functional domain of GLUT4 gene to screen for representative mutations. TaqMan PCR was used to genotyping then analyzed the relationship between locis of GLUT4 and hypoxia.</p><p><b>RESULTS</b>GLUT4 genome sequencing was performed in 96 severe OSAS patients and 4 mutated sites were found, among which 3 mutated sites (rs5415, rs4517, and rs5435) were selected according to the principle of linkage disequilibrium (r² > 0.8) and minimum gene allele frequency > 5%. All of single nucleotide polymorphisms (SNP) satisfied Hardy-Weinberg equilibrium (P>0.05). A significant association of GLUT4 SNP rs5417 allele carried in control subjects, compared with moderate and severe hypoxia in OSAS patients (P<0.05); AA+AC genotype relative to CC with low oxygen levels in subjects significantly reduced. The difference existed in overweight and obese patients, as well as in those aged more than 50 years (P<0.05). AA was still an independent protective factor for hypoxia caused by OSAS (OR=0.385, 95%CI = 0.210-0.704, P=0.002). Male (OR=1.635, 95% CI=1.037-2.577, P=0.034) and total cholesterol (OR=1.600, 95% CI=1.287-1.987, P<0.001) were independent risk factors associated with hypoxia. Normal weight(OR=0.059, 95% CI=0.037-0.094, P<0.001) and high density lipoprotein cholesterol (OR=0.337, 95% CI=0.171-0.666, P=0.002)were independent protective factors for hypoxia. The levels of monocyte chemoattractant protein-1 and C-reaction protein above CC were significantly higher than AA+AC (P<0.05).</p><p><b>CONCLUSION</b>Hypoxia caused by OSAS is associated with GLUT4 gene SNP rs5417.</p>

p42/p44 mitogen-activated protein kinases inhibit atrial natriuretic peptide mRNA transcription in gp130-mediated hypertrophic ventricular myocytes

OBJECTIVE@#To understand the role of ANP mRNA transcription regulation in gp130-mediated cardiomyocyte hypertrophy, and the involved mitogen-activated protein kinase kinase (MEK)-extracellular signal-regulated kinase (ERK, also called p42/p44 MAPK) signaling pathway.@*METHODS@#Isolated neonatal ventricular myocytes were treated with different concentrations of CT-1 (10(-9), 10(-8)and 10(-7)mol/L). MTT was used to analyze the viability and RT-PCR was used to detect ANP mRNA levels in cardiomyocyte. To inhibit p42/p44 MAPK activity in hypertrophic cardiomyocytes, the cells were pretreated with a specific MEK1 inhibitor.@*RESULTS@#CT-1 significantly induced ANP mRNA expression and the viability of cardiomyocytes in a dose- and time-dependent manner. Furthermore, blocking p42/p44 MAPK activity by the special MEK1 inhibitor upregulated the ANP mRNA.@*CONCLUSIONS@#p42/p44 MAPK have an important role in suppressing ANP mRNA transcription and cell activity in gp130-mediated hypertrophic ventricular myocytes.

Construction and characterization of a full-lengh cDNA library from non-fresh Giardia lamblia

OBJECTIVE@#To construct rapidly a full-length cDNA library from nanogram amounts total RNA of Giardia lamblia (G. lamblia) trophozoites stocked in RNA stabilization reagent.@*METHODS@#Total RNA of Giardia was extracted using Trizol reagent. A full-length cDNA library of G. lamblia trophozoites was constructed by a long-distance PCR (LD-PCR) method. The recombinant rate and the coverage rate of full-length clones of the library were evaluated. The inserted fragments were identified and sequenced by PCR amplification.@*RESULTS@#The titer of cDNA library was 3.85 × 10(7) pfu/mL. The length of inserted fragments ranged from 0.4 to 2.5 kb, and the recombination efficiency accounted for 100% (20/20). The coverage rate of full-length clones is high (17/20).@*CONCLUSIONS@#The RNA stabilization reagent may be used to fix the cells and prevent the RNA in cells even though delivered under normal atmospheric temperature. The long-distance PCR can be used to construct a full-length cDNA library rapidly and it needs less RNA than the traditional method from mRNA.

Inhibition of Pim-1 attenuates the proliferation and migration in nasopharyngeal carcinoma cells

OBJECTIVE@#To explore the role of proto-oncogene Pim-1 in the proliferation and migration of nasopharyngeal carcinoma (NPC) cells.@*METHODS@#Pim-1 expressions in NPC cell lines CNE1, CNE1-GL, CNE-2Z and C666-1 were examined by RT-PCR, western blotting and immunoflucesence, respectively. After CNE1, CNE1-GL and C666-1 cells were treated with different concentrations of Pim-1 special inhibitor, quercetagetin, the cell viability, colony formation rate and migration ability were analyzed.@*RESULTS@#Pim-1 expression was negative in well-differentiated CNE1 cells, whereas expressed weakly positive in poor-differentiated CNE-2Z cells and strongly positive in undifferentiated C666-1 cells. Interestingly, CNE1-GL cells that derived from CNE1 transfected with an Epstein Barr virus latent membrane protein-1 over-expression plasmid displayed stronger expression of Pim-1. Treatment of CNE1-GL and C666-1 cells with quercetagetin significantly decreased the cell viability, colony formation rate and migration ability but not the CNE1 cells.@*CONCLUSIONS@#These findings suggest that Pim-1 overexpression contributes to NPC proliferation and migration, and targeting Pim-1 may be a potential treatment for anti-Pim-1-expressed NPCs.

Etiology analysis for hospitalized hypertensive patients: 10 years report from the department of hypertension (1999 - 2008) / 中华心血管病杂志

<p><b>OBJECTIVE</b>To analyze etiology of hospitalized hypertensive patients in the department of hypertension from 1999 to 2008.</p><p><b>METHODS</b>This retrospective study was performed to analyze the etiology of hospitalized hypertensive patients in department of hypertension and to show the distribution change of hypertension from 1999 to 2008.</p><p><b>RESULTS</b>(1) There were 5867 (75.1%) patients with essential hypertension and 1942 (24.9%) patients with secondary hypertension (SH). (2) The prevalence rate of SH increased significantly during the 10 years (χ(2) = 387.621, P < 0.001) and was higher in 2008 than in 1999 (39.3% vs. 9.5%, P < 0.05). The prevalence of obstructive sleep apnea syndrome (OSAS) and primary aldosteronism (PA) in 2008 increased 38.3 and 1.8 times respectively than in 1999 (χ(2) = 304.025, P < 0.001; χ(2) = 42.845, P < 0.001) and other SH remained unchanged. (3) The prevalence of PA complicated with OSAS increased significantly in recent five years (χ(2) = 26.376, P < 0.001). Incidence of OSAS was 23.9% in PA patients and incidence of PA was 6.7% in OSAS patients.</p><p><b>CONCLUSIONS</b>With the insights gained on hypertension mechanism and the development of new diagnostic technology, percent of diagnosed SH increased remarkably in recent years in hospitalized hypertensive patients in our department of hypertension. OSAS and PA are the leading causes of SH.</p>