Peroxisome proliferator activated receptor gamma Pro12Ala: old topic of conversation and new question / 中国医学科学院学报

Comments concerning Meta analysis for relationship between peroxisome proliferator activated receptor gamma Pro12Ala polymorphism and type 2 diabetes susceptibility in different cohorts in this mini review were given. The comments pointed out existent problems and presented suggestions for genetic analysis of diseases in Chinese populations.

Adenovirus construction of expression and its function of connective tissue growth factor / 中国医学科学院学报

<p><b>OBJECTIVE</b>To construct and identify a adenovirus vector of the expression of connective tissue growth factor (CTGF) and to explore the role of CTGF in the metabolism of glucose and lipid.</p><p><b>METHODS</b>The over-expressed plasmid of CTGF was cloned, and then the CTGF sequences were cloned into pAdTrack-CMW vector. The reformed E. coli BJ5183-sensitive bacteria that contain pAdEasy-1 were transformed with lined vector cut by Pme I enzyme. The recombinant adenovirus vector was cut with Pac I enzyme and obtained, then transfected 293A cells to produce virus. Through three times of amplification, the adenovirus infected the primary hepatocytes to determine the infection efficiency and CTGF expression. The mice were starved for several time periods, and then the liver RNA was extracted for real-time PCR to detect the expressions of CTGF under different nutritional conditions.</p><p><b>RESULTS</b>The adenovirus of CTGF was successfully produced with an infection efficiency of 90%. The expressions of the CTGF were different under different nutritional conditions and showed a coincidence with the expression of peroxisome proliferators-activated receptor gamma coactivator 1 alpha. After the mice were starved for 24h, the expression of CTGF increased by (2.38 +/- 0.51) folds; after the mice were starved for 48 h, the expression of CTGF increased by (2.95 +/- 0.57) folds (P < 0.05).</p><p><b>CONCLUSION</b>CTGF is speculated to be involved in the metabolism of glucose and lipids.</p>

A second protein marker of caveolae: caveolin-2 / 中国医学科学杂志(英文版)

Caveolin-2, a protein about 20 kD, is a major component of the inner surface of caveolae, small invaginations of the plasma membrane. Similar with caveolin-1 and caveolin-3, it serves as a protein marker of caveolae. Caveolin-1 and -2 are located next to each other at 7q31.1 on human chromosome, the proteins encoded are co-localized and form a stable hetero-oligomeric complex, distributing similarly in tissue and cultured cells. Caveolin-3 is located on different chromosomes but confirmed to interact with caveolin-2. Caveolin-2 is similar to caveolin-1 in many respects but differs from the latter in functional domains, especially in G-protein binding domain and caveolin scaffolding domain. The mRNAs of both caveolin-1 and caveolin-2 are most abundantly expressed in white adipose tissue and are induced during differentiation of 3T3-L1 cells to adipocytes. Caveolin-2-deficient mice demonstrate clear pulmonary defects, with little or no change in caveolin-1 expression and caveolae formation, suggesting that caveolin-2 plays a selective role in lung functions. Caveolin-2 is also involved in lipid metabolism and human cancers.

Genetic analysis of complex diseases: status quo and prospects / 中国医学科学院学报

This review comments the status quo, especially the major problems, of the genetic analysis of the complex diseases, provides some possible solutions, and explores the further development trends in this field.

Coactivators in energy metabolism: peroxisome proliferator-activated receptor-gamma coactivator 1 family / 中国医学科学院学报

Peroxisome proliferator-activated receptor gamma coactivator 1 (PGC1) family is highly expressed in tissues with high energy metabolism. They coactivate transcription factors in regulating genes engaged in processes such as gluconeogenesis, adipose beta-oxydation, lipoprotein synthesis and secretion, mitochondrial biogenesis, and oxidative metabolism. Protein conformation studies demonstrated that they lack DNA binding domains and act as coactivators through physical interaction with transcription factors. PGC1 activity is regulated at transcription level or by multiple covalent chemical modifications such as phosphorylation, methylation and acetylation/deacetylation. Abnormal expression of PGC1 coactivators usually is closely correlated with diseases such as diabetes, obesity, hyperglycemia, hyperlipemia, and arterial and brain neuron necrosis diseases.

Research advances in Sirt1 gene / 中国医学科学院学报

As the most homologic homologue of silent information regulator 2 of yeast, Sirt1 gene is extensively expressed in mature tissues, and is rich in early embryo and reproductive cells. It is involved in the regulation of gene transcription, energy metabolism and cell aging. It promotes fat mobilization in adipocytes and glucose production in liver and regulates insulin secretion in islet beta cell. Furthermore, Sirt1 gene is an essential endogenous apoptosis inhibitor. In future, it may be used as new drug targets or applied in other disease management modalities.

Current situation researching of methylation in tumor / 中国医学科学院学报

The disorders of DNA and histone methylation have a close relationship with the development and progression of tumors. Epigenetic regulation is critical in maintaining the stability and integrity of the expression profiles of different cell types by modifying DNA methylation and histone methylation. However, the abnormal changes of methylation often result in the development and progression of tumors. This review summarized the theory of tumor genomic and histone methylation, detection methods of methylation and their applications, and the clinical application of methylation as biological markers and drug targets.

Gene expression profile of human skeletal muscle and adipose tissue of Chinese Han patients with type 2 diabetes mellitus / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To study the differential patterns of gene expression in skeletal muscle and adipose tissue between type 2 diabetes mellitus (T2DM) patients and healthy subjects using DNA microarray analysis.</p><p><b>METHODS</b>T2DM patiens were divided into female group, young male group and old male group. DNA microarray analysis and quantitative real-time PCR were carried out to analyze the relation between gene expressions and T2DM.</p><p><b>RESULTS</b>The mRNA expression of 298, 578, and 350 genes was changed in the skeletal muscle of diabetes mellitus patients compared with control subjects. The 1320, 1143, and 2847 genes were modified in adipose tissue of the three groups. Among the genes surveyed, the change of 25 and 39 gene transcripts in skeletal muscle and adipose tissue was > or = 2 folds. These differentially expressed genes were classified into 15 categories according to their functions.</p><p><b>CONCLUSION</b>New genes are found and T2DM can be prevented or cured.</p>

Regulation of tyrosylprotein sulfotransferases activity by sulfotyrosine / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the role of sulfated tyrosine in regulating the activity of tyrosylprotein sulfotransferases (TPST) 1 and TPST2.</p><p><b>METHODS</b>Constructs of TPST 1 and TPST2 were amplified by polymerase chain reaction (PCR), then fused into immunoglobulin G1 Fc region. All the variants in which sulfated tyrosines were mutated to phenylalanine were made by the PCR-based Quick Change method and confirmed by sequencing the entire reading frame. Small hairpin RNA (shRNA) constructs-targeting nucleotides 259-275 of TPST1 and nucleotides 73-94 of TPST2 were generated and subcloned into pBluescript. Human embryonic kidney (HEK) 293T cells were transfected with these plasmids. One day later, cells were split: one part was labeled with 35S-cysteine and methionine or 35S-Na2SO3 overnight, the second part was used for 125I labeled binding experiment, and the third part was retained for binding and flow cytometry.</p><p><b>RESULTS</b>Tyrosines at position 326 of TPST1 and position 325 of TPST2 were sulfated posttranslationally. Tyrosine sulfation of TPSTs was effectively inhibited by sulfation inhibitors, including specific shRNAs and non-specific NaCIO3. shRNAs reduced the sulfation of C3a receptor and C5a receptor, and partially blocked the binding of these two receptors to their respective ligands.</p><p><b>CONCLUSIONS</b>The activities of TPSTs were regulated by tyrosine sulfation. Inhibition of sulfotyrosine decreases the binding ability of C3a receptor and C5a receptor to their respective ligands.</p>

Liver X receptor: crucial mediator in lipid and carbohydrate metabolism / 中国医学科学院学报

Liver X receptors (LXRs) are members of the nuclear receptor superfamily and are activated by oxysterols and intermediates in the cholesterol synthetic pathway. The pivotal role of LXRs in the metabolic conversion of cholesterol to bile acids has been well established. Furthermore, insulin induces LXRa in hepatocytes, resulting in the suppression of key enzymes in gluconeogenesis, including phosphoenolpyruvate carboxykinase, glucose-6-phosphatase, and fructose-1, 6-bisphosphatase (FBPase). LXRs also play an important role in fatty acid metabolism by activating the sterol regulatory element-bing protein 1c gene (SREBP1c). This articles reviews the molecular mechanisms by which LXRs act to influence the lipid and carbohydrate metabolism.

Association analysis of 30 type 2 diabetes candidate genes in Chinese Han population / 中国医学科学院学报

<p><b>OBJECTIVE</b>To identify the susceptibility genes of type 2 diabetes in Chinese Han population.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSION</b>KCNJII gene is one of the susceptibility genes of type 2 diabetes in Chinese Han population.</p>

Research development of Mendelian inherited diabetes / 中国医学科学院学报

Diabetes mellitus is a chronic syndrome of abnormal metabolism, determined by interaction of multifactorial genetic and environmental factors. Some specific types of diabetes, such as MODY, Leprechaunism, lipoatrophic diabetes, and Rabson-Mendenhall syndrome, are monogenic forms of diabetes and are inherited as a Mendelian pattern. The article reviews the research development of these Mendelian inherited diabetes will be reviewed.

Screening susceptibility genes of type 2 diabetes in Chinese population by single nucleotide polymorphism analysis / 中国医学科学院学报

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSION</b>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.</p>

Nuclear localization region in soluble adenylyl cyclase / 中国医学科学院学报

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

Genes differentially expressed in human lung fibroblast cells transformed by glycidyl methacrylate / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To define the differences in gene expression patterns between glycidyl methacrylate (GMA)-transformed human lung fibroblast cells (2BS cells) and controls.</p><p><b>METHODS</b>The mRNA differential display polymerase chain reaction (DD-PCR) technique was used. cDNAs were synthesized by reverse transcription and amplified by PCR using 30 primer combinations. After being screened by dot blot analysis, differentially expressed cDNAs were cloned, sequenced and confirmed by Northern blot analysis.</p><p><b>RESULTS</b>Eighteen differentially expressed cDNAs were cloned and sequenced, of which 17 were highly homologous to known genes (homology = 89%-100%) and one was an unknown gene. Northern blot analysis confirmed that eight genes encoding human zinc finger protein 217 (ZNF217), mixed-lineage kinase 3 (MLK-3), ribosomal protein (RP) L15, RPL41, RPS 16, TBX3, stanniocalcin 2 (STC2) and mouse ubiquitin conjugating enzyme (UBC), respectively, were up-regulated, and three genes including human transforming growth factor beta inducible gene (Betaig-h3), alpha-1,2-mannosidase 1A2 (MAN 1A2) gene and an unknown gene were down-regulated in the GMA-transformed cells.</p><p><b>CONCLUSION</b>Analysis of the potential function of these genes suggest that they may be possibly linked to a variety of cellular processes such as transcription, signal transduction, protein synthesis and growth, and that their differential expression could contribute to the GMA-induced neoplastic transformation.</p>

Genotoxic and nongenotoxic effects of glycidyl methacrylate on human lung fibroblast cells / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To evaluate the genotoxic and nongenotoxic effects of short-term exposure to glycidyl mathacrylate (GMA) on human lung fibroblast cells (2BS cells) in vitro.</p><p><b>METHODS</b>DNA strand breakage was determined by single cell gel electrophoresis, and DNA ladder formation assay and flow cytometric analysis were carried out to detect apoptic responses of cells to GMA exposure. The HPRT gene mutation assay was used to evaluate the mutagenicity, and the effect of GMA on gap junctional intercellular communication (GJIC) in the exposed cells was examined with the scrape loading/dye transfer technique. The ability of GMA to transform 2BS cells was also tested by an in vitro cell transformation assay.</p><p><b>RESULTS</b>Exposure to GMA resulted in a dose-dependent increase in DNA strand breaks but not apoptic responses. GMA was also shown to significantly induce HPRT gene mutations and morphological transformation in 2BS cells in vitro. In contrast, GMA produced a concentration-dependent inhibition of GJIC.</p><p><b>CONCLUSIONS</b>GMA elicits both genotoxic and nongenotoxic effects on 2BS cells in vitro. The induction of DNA damage and gene mutations and inhibition of GJIC by GMA may casually contribute to GMA-induced cell transformation.</p>

Manual microdissection of defined cells and RNA extraction for gene expression analysis of esophageal carcinoma progress / 中国医学科学院学报

<p><b>OBJECTIVES</b>To isolate cells of interest from heterogeneous tissue blocks to obtain accurate representations of molecular alterations acquired by neoplastic cells so as to meet the demands of further study on gene expression patterns of the esophageal carcinoma (EC) evolution.</p><p><b>METHODS</b>Blocks of EC were stored at -70 degrees C as close as possible to the time of surgical resection. The tissue block was embedded in OCT and frozen sections of 35 microns in thickness were cut in a cryostat under strict RNAse-free conditions. Individual frozen sections were mounted on plain glass slides and 30-gauge needle attached to a 1 ml syringe was used to microdissect defined cells in the sections. The procured cells were used for total RNA extraction.</p><p><b>RESULTS</b>An optimized protocol of manual microdissection was developed successfully whereby regions with an area as small as 1/25 mm2 could be accurately dissected. The RNA recovered from procured cells was of high quality suitable for subsequent applications of molecular analysis as assessed of 18S and 28S rRNAs by electrophoresis on agarose gel.</p><p><b>CONCLUSIONS</b>It is believed that manual microdissection is capable to procure defined cell populations from complex primary tissues, thus allowing investigation of tissue-, cell-, and function-specific gene expression patterns. The technique is simple, easy to perform, versatile, and of particular usefulness when laser capture microdissection (LCM) is practically unavailable.</p>

Anticancer drug resistance of HeLa cells transfected with rat glutathione S-transferase pi gene / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSIONS</b>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.</p>

The association of two single nucleotide polymorphisms in PRKCZ and UTS2 respectively with type 2 diabetes in Han people of northern China / 中国医学科学院学报

<p><b>OBJECTIVE</b>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).</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSIONS</b>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.</p>

Single nucleotide polymorphisms in CAPN10 gene of Chinese population and its correlation with type 2 diabetes mellitus in Han people of northern China / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the distribution of the single nucleotide polymorphisms (SNPs) in CAPN10 gene in Chinese population and their relation with type 2 diabetes mellitus in Han people of Northern China.</p><p><b>METHODS</b>CAPN10 gene was sequenced to detect SNPs in 27 samples of different nationalities in China. 5 SNPs were genotyped with single-base extension (SBE) method to perform case-control study in 156 normal Han people of Northern China and 173 type 2 diabetes and the 3 positive loci reported in the article were performed haplotype analysis. One positive locus was also analyzed with transmission-disequilibrium test (TDT) and sib transmission-disequilibrium test (STDT) in 68 type 2 diabetes pedigrees (377 cases).</p><p><b>RESULTS</b>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 was different from that reported in American Mexicans. There was no significantly statistical difference in the allele frequency of the 5 SNPs between case and control (P > 0.05), and the haplotype frequencies in the two groups were not much different (P > 0.05). There was no positive results in TDT and STDT analysis (P > 0.05).</p><p><b>CONCLUSIONS</b>The SNP distribution of CAPN10 gene varies with 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.</p>