Biomedical subjects

Jin Zuo

Publications and source records attributed to Jin Zuo.

At least 19 recordsLinked to original sources

PubMed2007

Genetic variations of the CDC2L2 gene are associated with type 2 diabetes in a Han Chinese cohort.

OBJECTIVE: The purpose of the present study was to study the potential association of CDC2L2 variations with type 2 diabetes (T2D). METHODS: SNPs (single nucleotide polymorphisms) were extensively screened across the CDC2L2 gene by the site-specific PCR method ARMS (Amplification Refractory Mutation System). The identified novel polymorphisms were further evaluated in a Han Chinese cohort comprising of 467 patients with diabetes and 569 nondiabetic controls. In addition, 76 parent-offspring trios were also included in this association study. The case-control and TDT/sibTDT studies are applied for association analysis in this study. RESULTS: Seven loci (rs1059831, SNP33, rs7528782, SNP11, SNP36, rs11488590 and SNP30) were shown to be significantly associated with T2D in unrelated individuals (p < 0.05). When individuals were stratified by age, sex and body mass index (BMI), the SNP11 was shown to be strongly associated with female patients with T2D, patients whose age was over 45 years and individuals whose BMI was less than 23 (p = 0.018, 0.011 and 0.0089, respectively). However, it was not replicated in the family-based TDT/sibTDT analysis (p = 0.085, OR = 0.63 (CI 95% 0.34-1.06)). CONCLUSION: Our data suggested that the CDC2L2 gene may contribute to the susceptibility of type 2 diabetes in the northern Han Chinese population, but further studies are needed to replicate these findings.

Adult↗

PubMed2006

Protein kinase Czeta mediates insulin-induced glucose transport through actin remodeling in L6 muscle cells.

Protein kinase C (PKC) zeta has been implicated in insulin-induced glucose uptake in skeletal muscle cell, although the underlying mechanism remains unknown. In this study, we investigated the effect of PKCzeta on actin remodeling and glucose transport in differentiated rat L6 muscle cells expressing myc-tagged glucose transporter 4 (GLUT4). On insulin stimulation, PKCzeta translocated from low-density microsomes to plasma membrane accompanied by increase in GLUT4 translocation and glucose uptake. Z-scan confocal microscopy revealed a spatial colocalization of relocated PKCzeta with the small GTPase Rac-1, actin, and GLUT4 after insulin stimulation. The insulin-mediated colocalization, PKCzeta distribution, GLUT4 translocation, and glucose uptake were inhibited by wortmannin and cell-permeable PKCzeta pseudosubstrate peptide. In stable transfected cells, overexpression of PKCzeta caused an insulin-like effect on actin remodeling accompanied by a 2.1-fold increase in GLUT4 translocation and 1.7-fold increase in glucose uptake in the absence of insulin. The effects of PKCzeta overexpression were abolished by cell-permeable PKCzeta pseudosubstrate peptide, but not wortmannin. Transient transfection of constitutively active Rac-1 recruited PKCzeta to new structures resembling actin remodeling, whereas dominant negative Rac-1 prevented the insulin-mediated PKCzeta translocation. Together, these results suggest that PKCzeta mediates insulin effect on glucose transport through actin remodeling in muscle cells.

Actins↗

PubMed2006

Rapid mapping of flow velocity using a new PARSE method.

A new method for flow velocity mapping is presented here. Instead of the conventional approach of employing two images (velocity sensitive and control) to generate velocity information, in the new method one determines the velocity directly from a single-shot acquisition by solving an inverse problem. This technique is a variant of single-shot parameter assessment by retrieval from signal encoding (SS-PARSE). The results of simulation and phantom studies show strong agreement with the actual velocities. The prototype method can measure velocities in the range of -50 to 50 cm/s, which is roughly appropriate for future applications in dynamic blood flow measurement in carotid arteries.

Algorithms↗

PubMed2006

[Association analysis of 30 type 2 diabetes candidate genes in Chinese Han population].

OBJECTIVE: To identify the susceptibility genes of type 2 diabetes in Chinese Han population. METHODS: Single nucleotide polymorphism (SNP) discovery, genotyping and haplotype construction were performed in 30 candidate genes. Case-control study were carried out in a population-based sample and confirmed by the transmission disequilibrium test (TDT) analysis in 77 trio pedigrees. The effects of the SNP rs5210 on gene expression were studied by reporter gene technique. RESULTS: The case-control studies showed that several SNPs on KCNJ11 gene was associated with type 2 diabetes in Chinese Han population, in which the allele frequency of SNP rs5219, the genotype frequency of rs5210, rs2285676 and rs5219, and the frequency of haplotype GA combined of the rs5219 and rs5215 showed significant difference between these two groups (P < 0.05). In addition, TDT test also showed statistical significance on this haplotype GA (P < 0. 05). The reporter gene assay showed that the effect on gene expression was significantly different between two alleles of rs5210 (P < 0.05). CONCLUSION: KCNJII gene is one of the susceptibility genes of type 2 diabetes in Chinese Han population.

Adult↗

PubMed2005

Two domains are critical for the nuclear localization of soluble adenylyl cyclase.

Soluble adenylyl cyclase (sAC) is a newly identified source of cyclic adenosine 3',5'-monophosphate (cAMP). Unlike the well-known transmembrane adenylyl cyclases (tmACs), sAC locates to the nucleus, mitochondria and microtubules. For most cAMP-signaling microdomains, there is always an AC nearby, for example tmAC. But it was until the discovery of sAC that there was not known cAMP resource in the nucleus. sAC associates with nuclear cAMP-signaling microdomains, which were once considered to depend on the diffusion of cAMP produced by tmAC. In this report, we focus on the truncated soluble adenylyl cyclase (tsAC), the most common existence form of sAC in tissues. Two domains (145-200 aa and 257-318 aa) related with sAC nuclear localization were present here. The findings provide evidence that these two domains are critical for the nuclear localization of sAC and they collocated with the catalytic domains.

Adenylyl Cyclases↗

PubMed2005

High glucose upregulates pantothenate kinase 4 (PanK4) and thus affects M2-type pyruvate kinase (Pkm2).

A new Rattus norvegicus PanK gene was isolated by mRNA differential display from high concentration glucose-stimulated rat, which encodes a human PanK4-like protein with KOG2201 and KOG4584 domain. Proteins that interact with rat PanK4 were identified by the application of the yeast two-hybrid system. One of the components, Pkm2, was found to be associated with rat PanK4 and its two domains under both in vitro and in vivo conditions. Immunofluorescence staining and confocal scanning experiments showed that PanK4 could transiently co-express with Pkm2 in the cytoplasm of HeLa cell and HEK293T cell. These findings suggest that PanK4 interacts with Pkm2 and thereby may modulate the glucose metabolism through regulating the activity of Pkm2.

Amino Acid Sequence↗

PubMed2005

[Screening susceptibility genes of type 2 diabetes in Chinese population by single nucleotide polymorphism analysis].

OBJECTIVE: To search for the susceptibility variant (s) of type 2 diabetes in the susceptible regions on chr.1 (1p36.23-36.33, 1q24.3-25.1, and 1q42.12-42.13) by genotyping SNP markers in case-control DNA samples and identifying the haplotype associated with type 2 diabetes. METHODS: Totally 124 SNPs in 33 candidate genes in the mapped regions were chosen from public SNP data or identified by sequencing the samples that were used to search for SNP locus. Sequencing method was used to genotype the loci for 236 sporadic type 2 diabetes patients and 152 normal subjects in Northern Han Chinese population. The haplotypes with significant difference were further analyzed. RESULTS: Of 124 SNPs successfully typed, 4 SNPs that showed association with diabetes status were found: rs203849 (P=0.005, OR=1.60) and rs203826 (P=0.016, OR=1.60) located in sAC gene, rs7535528 (P=0.028, OR=1.45) located in PANK4, rs884363 (P=0.043, OR=1.37) located in CASP9 gene. In addition, the frequencies of two combination types from these 4 SNP genotypes were significantly different between case and control groups (P < 0.001). Furthermore, four haplotypes associated with diabetes were found in haplotype analysis of sAC gene. CONCLUSION: sAC, PANK4, and CA SP9 may be associated with type 2 diabetes in Han population in north China, and it seems that the synergetic effect of these genes is responsible for the development of type 2 diabetes.

Adult↗

PubMed2005

[Nuclear localization region in soluble adenylyl cyclase].

OBJECTIVE: To locate the region responsible for nuclear localization of protein sAC. METHODS: The eukaryotic expression vector of vairous sAC deletion mutants were transfected into Hela cells. The localization of each mutant was observed using confocal microscope. RESULTS: For some mutants, the localization of sAC changed. Deletion of some region made it unable to locate in the nuclear. CONCLUSION: It is possible to figure out that the nucleotide region (739-1038 and 1045-1261) take charge of nuclear localization of sAC.

Adenylyl Cyclases↗

PubMed2004

Effect of SNPs in protein kinase C zeta gene on gene expression in the reporter gene detection system.

AIM: To investigated the effects of the SNPs (rs411021, rs436045, rs427811, rs385039 and rs809912) on gene expression and further identify the susceptibility genes of type 2 diabetes. METHODS: Ten allele fragments (49 bp each) were synthesized according to the 5 SNPs mentioned above. These fragments were cloned into luciferase reporter gene vector and then transfected into HepG2 cells. The activity of the luciferase was assayed. Effects of the SNPs on RNA splicing were analyzed by bioinformatics. RESULTS: rs427811T allele and rs809912G allele enhanced the activity of the reporter gene expression. None of the 5 SNPs affected RNA splicing. CONCLUSION: SNPs in protein kinase Cz (PKCZ) gene probably play a role in the susceptibility to type 2 diabetes by affecting the expression level of the relevant genes.

Base Sequence↗

PubMed2003

Protein kinase C/zeta (PRKCZ) gene is associated with type 2 diabetes in Han population of North China and analysis of its haplotypes.

AIM: To identify the susceptible gene (s) for type 2 diabetes in the previously mapped region, 1p36.33-p36.23, in Han population of North China using single nucleotide polymorphisms (SNPs) and to analyze the haplotypes of the gene (s) related to type 2 diabetes. METHODS: Twenty three SNPs located in 10 candidate genes in the mapped region were chosen from public SNP domains with bioinformatic methods, and the single base extension (SBE) method was used to genotype the loci for 192 sporadic type 2 diabetes patients and 172 normal individuals, all with Han ethical origin, to perform this case-control study. The haplotypes with significant difference in the gene (s) were further analyzed. RESULTS: Among the 23 SNPs, 8 were found to be common in Chinese Han population. Allele frequency of one SNP, rs436045 in the protein kinase C/zetagene (PRKCZ) was statistically different between the case and control groups(P<0.05). Furthermore, haplotypes at five SNP sites of PRKCZ gene were identified. CONCLUSION: PRKCZ gene may be associated with type 2 diabetes in Han population in North China. The haplotypes at five SNP sites in this gene may be responsible for this association.

Asian People↗

PubMed2003

Anticancer drug resistance of HeLa cells transfected with rat glutathione S-transferase pi gene.

OBJECTIVE: To establish a cytologic expressing system of rat glutathione S-transferase pi (GST-pi) cDNA for detecting the resistance of HeLa cells to anticancer drugs. METHODS: The assessment was made with various anticancer drugs (adriamycin, mitomycin, cisplatinum and vincristine) that showed different cytotoxicities in transfectant HeLa cells with pSV-GT containing rat GST-pi cDNA (HeLa/pSV-GT) or control pSV-neo (HeLa/pSV-neo). Expression levels of GST-pi mRNA in HeLa/pSV-GT and HeLa/pSV-neo were measured by in situ hybridization using Digoxin-labelled cDNA probe. RESULTS: HeLa/pSV-GT expressed significantly high degree of GST-pi mRNA, whereas both HeLa/pSV-neo and HeLa cells had very low expression. Cytotoxicities of HeLa/pSV-GT and HeLa/pSV-neo with 4 anticancer drugs were measured by MTT assay. Drug concentrations for yielding 50% inhibition (IC50) in HeLa/pSV-GT by adriamycin, mitomycin and cisplatinum were 70.13 microg/mL, 10.95 microg/mL and 16.52 microg/mL, respectively. In contrast, IC50 in HeLa/pSV-neo was 10.34 microg/mL, 7.48 microg/mL and 13.70 microg/mL, respectively. The cytotoxicities of vincristine on both HeLa/pSV-GT and HeLa/pSV-neo were not significantly different. CONCLUSIONS: Our findings suggest that HeLa/pSV-GT containing rat GST-pi cDNA is resistant to some anticancer drugs due to overexpression of GST-pi. Also, HeLa/pSV-GT cell line could serve as a useful cytogenetic model for further research.

Animals↗

PubMed2003

[The fibroblast primary cell culture by the split-thickness skin slide technique].

OBJECTIVE: To acquire lots of cell to culture during the primary cell culture. METHOD: We take the split-thickness skin slide technique to acquire the dissociated fibroblast cell in two big-ear rats. RESULTS: The cell number is above 10(6) from 1 cm x 2 cm split-thickness skin slide and the technique is simple, economic, effectve. CONCLUSION: We think this way is better than other methods, and should be adopted in the primary cell culture, especially in fibroblast transplantation by injection.

Animals↗

PubMed2002

Effect of trans-acting factor on rat glutathione S-transferase P1 gene transcription regulation in tumor cells.

OBJECTIVE: To investigate the effect of trans-acting factor(s) on rat glutathione S-transferase P1 gene (rGSTP1) transcription regulation in tumor cells. METHODS: The binding of trans-acting factor(s) to two enhancers of the rGSTP1 gene, glutathione S-transferase P enhancer I (GPEI) and glutathione S-transferase P enhancer II-1 (GPE II-1), was identified by an electrophoretic mobility shift assay (EMSA). The molecular weight of trans-acting factor was measured in a UV cross-linking experiment. RESULTS: Trans-acting factor interacting with the core sequence of GPEI (cGPEI) were found in human cervical adenocarcinoma cell line (HeLa) and rat hepatoma cell line (CBRH7919). These proteins were not expressed in normal rat liver. Although specific binding proteins that bound to GPE II-1 were detected in all three cell types, a 64 kDa binding protein that exists in HeLa and CBRH7919 cells was absent in normal rat liver. CONCLUSION: cGPEI, GPEII specific binding proteins expressed in HeLa and CBRH7919 cells may play an important role in the high transcriptional level of the rGSTP1 gene in tumor cells.

Animals↗

PubMed2002

Yeast one-hybrid system used to identify the binding proteins for rat glutathione S-transferase P enhancer I.

OBJECTIVE: To detect the trans-factors specifically binding to the strong enhancer element (GPEI) in the upstream of rat glutathione S-transferase P (GST-P) gene. METHODS: Yeast one-hybrid system was used to screen rat lung MATCHMAKER cDNA library to identify potential trans-factors that can interact with core sequence of GPEI(cGPEI). Electrophoresis mobility shift assay (EMSA) was used to analyze the binding of transfactors to cGPEI. RESULTS: cDNA fragments coding for the C-terminal part of the transcription factor c-Jun and rat adenine nucleotide translocator (ANT) were isolated. The binding of c-Jun and ANT to GPEI core sequence were confirmed. CONCLUSIONS: Rat c-jun transcriptional factor and ANT may interact with cGPEI. They could play an important role in the induced expression of GST-P gene.

Animals↗

PubMed2002

Single nucleotide polymorphisms in CAPN10 gene of Chinese people and its correlation with type 2 diabetes mellitus in Han people of northern China.

OBJECTIVE: To investigate the distribution of single nucleotide polymorphisms (SNPs) in CAPN10 gene in Chinese population and their relation with type 2 diabetes mellitus in Han people of Northern China. METHODS: CAPN10 gene was sequenced to detect SNPs in different nationalities of China. Five SNPs were chosen to perform case-control study and haplotype analysis in 156 normal Han people of Northern China and 173 type 2 diabetes. One SNP was also analyzed with transmission-disequilibrium test (TDT) and sib transmission-disequilibrium test (STDT) in 68 type 2 diabetes pedigrees (377 people). RESULTS: A total of 40 SNPs were identified in length of 8,936 bp, with an average of 1 in every 223 bp. The SNPs in CAPN10 gene did not distribute evenly and the SNPs in Chinese were different from those reported in Mexican American. There was no significantly statistical difference in the allele frequency of the 5 SNPs between case and control, and the haplotype frequencies in the two groups were not significantly different. No positive results was found in TDT and STDT analysis. CONCLUSIONS: The SNP distribution of CAPN10 gene differs in different nationalities. The studied SNPs in CAPN10 gene may not be the major susceptibility ones of type 2 diabetes mellitus in Han people of Northern China.

Calpain↗

PubMed2002

[Synergistic effect of all-trans retinoic acid and herpes simplex virus thymidine kinase gene on glioma].

BACKGROUND & OBJECTIVE: Gap junctional intercellular communication (GJIC) is the main mechanism mediating the bystander effect in herpes simplex virus thymidine kinase (HSV-tk) gene therapy. All-trans retinoic acid (ATRA) may augment the therapeutic efficacy of HSV-tk gene therapy by both upregulating GJIC in glioma cells and inhibiting tumor growth. This study was designed to investigate the synergistic effect of ATRA and HSV-tk gene therapy in treatment of glioma. METHODS: Rat C6 glioma cells were exposed to ATRA at concentrations of 1 mumol/L, 10 mumol/L, or 100 mumol/L, respectively. The effects of ATRA on C6 glioma cell differentiation, proliferation, GJIC, and connexin 43 (Cx 43) gene transcription were studied. C6 cells and C6tk cells, a stable transfectant of HSV-tk gene, mixed at various ratios. The mixtures were treated with GCV with ATRA at various concentrations or without ATRA, and the bystander effect was measured with MTT assay in 7 days after treatment. RESULTS: A morphological change of differentiation was observed in C6 glioma cells after exposure to each concentration of ATRA. The proliferation of C6 cells was also significantly inhibited by ATRA, majority of living cells being arrested at G1 phase, especially at the concentration of 100 mumol/L. At the concentration of 100 mumol/L, ATRA also induced significant apoptosis in C6 glioma cells. The GJIC was significantly enhanced in C6 cells after ARTA treatment at each concentration, while there was no ATRA induced effect observed upon Cx43 transcription. The results of bystander effect assay revealed that ATRA at each concentration exerted a significant augmentation effect on bystander effect. CONCLUSION: The combination of two clinically safe protocols, ATRA and HSV-tk/GCV gene therapy, resulted in a synergistic effect in glioma treatment, and would become a promising strategy for clinical administration.

Animals↗

PubMed2002

The effect of all-trans retinoic acid on gap junctional intercellular communication and connexin 43 gene expression in glioma cells.

OBJECTIVE: To illuminate the regulating effect of all-trans retinoic acid (ATRA) on gap junctional intercellular communication (GJIC) and connexin 43 (Cx43) gene expression in glioma cells, which is tissue- and organ-specific. METHOD: Rat C6 glioma cells were exposed to ATRA at a concentration of 1, 10, 100 micromol/L and the GJIC function of the cells was examined with scrape-loading dye transfer assay 24 hours, 48 hours and 72 hours after ATRA treatment. The effect of ATRA on Cx43 gene expression was measured with semiquantitative reverse transcription polymerase chain reaction (RT-PCR) 24 hours after ATRA exposure. RESULTS: The GJIC function of C6 glioma cells was significantly increased by ATRA at each concentration applied. The dye passed 4 to 5 rows of cells from the scraping edge in ATRA treated cells, but only 1 or 2 rows in the control. The augment effect was observed 24 hours after each concentration ATRA treatment, and lasted till 72 hours after treatment with 1 micromol/L and 10 micromol/L ATRA. Forty-eight hours after exposed to 100 micromol/L ATRA, the enhancement of GJIC was less obvious. There was no significant increase induced by ATRA on the transcription of Cx43 gene, as demonstrated by semiquantitative RT-PCR. CONCLUSION: ATRA turned out to be a potent enhancer on GJIC function in C6 glioma cells, andthe enhancement effect was most probable at post-transcriptional level.

Animals↗

PubMed2002

[The association of two single nucleotide polymorphisms in PRKCZ and UTS2 respectively with type 2 diabetes in Han people of northern China].

OBJECTIVE: To probe the candidate susceptibility gene (s) of type 2 diabetes in the formal mapping region, 1p36.33-p36.23, in Han people of Northern China using single nucleotide polymorphisms (SNPs). METHODS: 23 SNPs located in 10 candidate genes in the mapping region were chosen from public SNP domain by bioinformatic methods and single base extension (SBE) method were used to genotype the loci in 192 sporadic type 2 diabetes patients and 172 normal individuals to perform case-control study. RESULTS: Among the 23 SNPs, 8 were found to be common in Chinese population. There were statistically different in the allele frequency of 2 SNP, rs436045 in the protein kinase C/xi gene and rs228648 in Urotensin II gene between case and control groups. CONCLUSIONS: The two SNP may be associated with type 2 diabetes in Han people of China, which makes base for further study of the relation between the genes they located with type 2 diabetes.

Alleles↗