[Analysis of TGFBI gene mutation in a pedigree affected with corneal dystrophy].

OBJECTIVE: To detect potential mutation in a large Chinese pedigree affected with congenital corneal dystrophy. METHODS: Two patients from the pedigree were subjected to whole exome sequencing to determine the candidate gene. Suspected mutation was verified in 13 additional members by directional Sanger sequencing. Ccorrelation between genotype and phenotype was explored. RESULTS: A missense mutation, c.1877A>C (p.His626Pro), was detected in exon 14 of the TGFBI gene in 8 patients from the pedigree, but not in five unaffected members and 100 unrelated healthy controls. Respectively, the mutation was predicted as "affecting protein function", "probably damaging" and "disease causing" by SIFT, PolyPhen-2 and MutationTaster. CONCLUSION: The c.1877A>C mutation of the TGFBI gene probably underlies the disease in this pedigree.

Variants in TRIM44 Cause Aniridia by Impairing PAX6 Expression.

Congenital aniridia is a genetic disorder that manifests as iris hypoplasia and other associated ocular complications. Mutations in the paired box 6 (PAX6) gene are considered the major cause of aniridia. In this study, we identified four mutations exclusively presented in aniridia patients from a four-generation Chinese pedigree, including two single nucleotide substitutions in the 3'UTR of PAX6 (NM_000280.4:c.[*76G>A; *2977C>A]) and two missense mutations in tripartite motif containing 44 (TRIM44, NM_017583.4:c.[191C>A; 463G>A]), which lead to amino acid changes p.S64Y and p.G155R, respectively. Bioinformatic analyses revealed that the two 3'UTR mutations of PAX6 disrupted microRNA binding motifs in the wildtype 3'UTR sequence. Luciferase reporter assay and Western blotting with predicted microRNAs showed that the two 3'UTR mutations could only increase or have no effect on the expression of PAX6. Therefore, they would not be the cause of aniridia that resulted from PAX6 deficiency. Instead, we found that overexpression of TRIM44 significantly reduced the expression of PAX6 in human lens epithelial cells, and the p.G155R mutant exhibited much stronger effect than the wildtype form. We conclude that inhibition of PAX6 expression by mutant TRIM44 is a novel pathogenic mechanism for aniridia.

Analysis of ischemic neuronal injury in Cav2.1 channel α1 subunit mutant mice.

One of the main instigators leading to cell death and brain damage following ischemia is Ca(2+) dysregulation. Neuronal membrane depolarization results in the activation of voltage-gated Ca(2+) (CaV) channels and intracellular Ca(2+) influx. We investigated the physiological role of the CaV2.1 (P/Q-type) channel in ischemic neuronal injury using CaV2.1 channel α1 subunit mutant mice, rolling Nagoya and leaner mice. The in vivo ischemia model with a complete occlusion of the middle cerebral artery showed that the infarct area at 24h was significantly smaller in rolling Nagoya (27.1±3.5% of total brain volume) and leaner (20.1±3.5%) mice compared to wild-type (42.9±4.5%) mice. In an in vitro Ca(2+) imaging study, oxygen-glucose deprivation using a hippocampal slice induced a significantly slower rate of increase in intracellular Ca(2+) concentration ([Ca(2+)]i) in rolling Nagoya (0.083±0.007/min) and leaner (0.062±0.006/min) mice compared to wild-type (0.105±0.008/min) mice. These results demonstrate that the mutant CaV2.1 channel in rolling Nagoya and leaner mice plays a different protective role in a ([Ca(2+)]i)-dependent manner in ischemic models and indicate that CaV2.1 channel blockers may be used preventively against ischemic injury.

Combinational analysis of linkage and exome sequencing identifies the causative mutation in a Chinese family with congenital cataract.

BACKGROUND: Congenital cataract is a Mendelian disorder that frequently causes blindness in infants. To date, various cataract-associated loci have been mapped; more than 30 genes have been identified by linkage analysis. However, the pathogenic loci in some affected families are still unknown, and new research strategies are needed. In this study, we used linkage-exome combinational analysis to further investigate the pedigree of a four-generation Chinese family with autosomal dominant coralliform cataract. METHODS: We combined whole exome sequencing and linkage analysis to identify the causative mutation. The exome capture and next-generation sequencing were used to sequence the protein-coding regions in the genome of the proband to identify rare mutations, which were further screened for candidate mutations in linkage regions. Candidate mutations were independently verified for co-segregation in the whole pedigree using Sanger sequencing. RESULTS: We identified a C to A transversion at nucleotide position c.70 in exon 2 of CRYGD, a cataract-associated gene. This mutation resulted in a threonine substitution for proline at amino acid residue 24. CONCLUSIONS: We identified a missense P24T mutation in CRYGD that was responsible for coralliform cataract in our studied family. Our findings suggest that the combination of exome sequencing and linkage analysis is a powerful tool for identifying Mendelian disease mutations that might be missed by the classic linkage analysis strategy.

Mutation identification of the DSPP in a Chinese family with DGI-II and an up-to-date bioinformatic analysis.

In this study, through linkage analysis of a four-generation Chinese family with multiple members afflicted with DGI (type II), we identified a novel missense mutation in DSPP. The mutation was located in exon 2 at the second nucleotide position of the last codon and resulted in a substitution of a proline with a leucine residue (c.50C>T, p.P17L, g.50C>T). To assess the potential effects of this novel mutation, we utilized various bioinformatics analysis programs. The results indicate that the mutation likely affects protein cleavage/trafficking. We also analyzed previously reported mutations of DSPP. In summary, our finding supports that the genomic sequence that corresponds to the P17 residue of DSPP is a mutational hotspot and P17 may be critical for the function of DSPP.

An Arg124His mutation in TGFBI associated to Avellino corneal dystrophy in a Chinese pedigree.

PURPOSE: To identify the gene mutation underlying Avellino corneal dystrophy in a four-generation Chinese pedigree. METHODS: Patients from the affected family underwent detailed clinical examination involving slit-lamp photography and confocal microscopy. Genomic DNA extracted from peripheral leukocytes was amplified using touch-down PCR for gene scanning. Two-point linkage analysis and haplotyping were performed to map the relevant chromosome region. The candidate gene in this region was sequenced to screen out the disease-causing mutation. RESULTS: Patients in the pedigree were diagnosed with Avellino corneal dystrophy. Using linkage analysis, the responsible gene was mapped to chromosome 5q31.2 with a maximum LOD (log odds) score (Z(max)) of 3.23 at D5S479 (θ(max)=0.0). Haplotypes constructed from 11 microstallite markers identified the disease-linked chromosome region as being below D5S808. Sequencing of TGFBI (transforming growth factor-beta induced gene), a known gene in this region, revealed a heterozygous transition (c.418 G>A) in exon 4 resulting in Arg124His (R124H) being co-segregated with the disease in affected family members but not in the unaffected members or the 50 unrelated controls. CONCLUSIONS: Our study demonstrated that a G>A transition in Arg124His of TGFBI was responsible for Avellino corneal dystrophy in a Chinese pedigree. This result further supports the importance of TGFBIp in maintaining transparency of the cornea.

Two FSHR variants, haplotypes and meta-analysis in Chinese women with premature ovarian failure and polycystic ovary syndrome.

In this study, two polymorphisms of follicle stimulating hormone receptor (FSHR) gene were analysed in the case-control sample using 40 premature ovarian failure (POF) patients, 60 polycystic ovary syndrome (PCOS) patients and 92 healthy controls. All subjects were unrelated Han Chinese from Shanghai. No difference was observed on the allelic or genotypic distribution of FSHR gene polymorphisms between the groups. However, the two-marker haplotypes covering components Thr307Ala (rs6165) G and Asn680Ser (rs6166) A were observed to be significantly associated with PCOS (p=0.007, corrected p=0.042). Meanwhile, a meta-analysis including our study (altogether six POF and eight PCOS studies) showed significant association between rs6166 marker and PCOS (p<0.05). The results suggest that FSH receptor might play a role in genetic susceptibility to PCOS. However, confirmatory studies in independent samples are needed.

A splice site mutation in CRYBA1/A3 causing autosomal dominant posterior polar cataract in a Chinese pedigree.

PURPOSE: To identify the mutant gene for autosomal dominant posterior polar congenital cataract in a four-generation Chinese pedigree. METHODS: The clinical data of patients from the family were recorded by slit-lamp photography. Genomic DNA samples from peripheral blood of the pedigree members were then isolated to map the relevant gene, using microsatellite markers for two-point linkage analysis. Genotype and haplotypes of the pedigree were constructed using Cyrillic software to locate the relevant region. Direct sequencing was performed to screen out the disease-causing mutation. RESULTS: The congenital cataract phenotype of the pedigree was labeled as the posterior polar type by using slit-lamp photography. Linkage analysis results indicated a maximum logarithm of odds LOD score of (Z(max)) 2.02 at D17S1800 (theta(max)=0.00). Haplotyping identified a 26-cM region flanked by D17S921 and D17S800 on 17p12-21.2, namely at the betaA1/A3-crystallin (CRYBA1/A3) gene locus. Sequencing revealed a splice site mutation, G-->A, at the first base of intron 3 of CRYBA1/A3, which co-segregated with the affected individuals in the pedigree but which was not found in the unaffected members of the family or in the 50 unrelated controls. CONCLUSIONS: Our results demonstrated that a splice site mutation of CRYBA1/A3 was responsible for the autosomal dominant posterior polar congenital cataract in a four-generation Chinese pedigree. The same mutation in this gene had previously been reported to be associated with other phenotype cataracts. This study is the first report relating a mutation of CRYBA1/A3 to posterior polar cataract.

Extracting Forest Parameters based on Stand Automatic Segmentation Algorithm.

Forest stand segmentation is a critical process for forest management and inventory. The forest stand segmentation accuracy will determine the forest stand level parameters quality. In this study, we developed an automatic forest stand segmentation algorithm based on ArboLiDAR, a software used to process Light Detection and Ranging (LiDAR) point cloud data. We then optimized the parameters for the algorithm to the Dayekou forest area on Qilian Mountain in China to find the most suitable parameters for automatic stand segmentation. Further, we extracting the forest parameters at the stand level based on Bysh method. Our results showed that the limited region growing method based on the gradient is the most suitable one for analyzing automatic stand segmentation in the studied area. Among our tested parameters groups, the fifth group contains the optimal parameters for the studied area. In addition, for forest parameters, the R2 of mean height (H), average diameter at breast height (D), basal area (G), and Stand volume (V) is 0.744, 0.720, 0.562, 0.696, respectively. The RMSE value is 5.24%, 28.57%, 19.93%, and 17.66%, respectively. Our study serves as a technical basis and reference for future studies that perform more efficient analyses on forest resource inventory in China.

Association between the PDE4D gene and ischaemic stroke in the Chinese Han population.

Recent findings suggests that PDE4D (gene encoding phosphodiesterase 4D) is a stroke-related gene in the Icelandic population, but it is still very controversial as to whether it is a susceptible gene for stroke in other populations. In the present study, we attempted to explore the role of the gene in the pathogenesis of stroke in the Chinese Han population of eastern China. A total of 649 ischaemic stroke patients and 761 unrelated control individuals with no history of stroke or transient ischaemic attack were examined in a case-control study. Four SNPs (single nucleotide polymorphisms) rs152312 (C/T), SNP56 (A/T), SNP83 (C/T) and SNP87 (C/T) with a minor allele frequency over 5% were genotyped and the corresponding haplotypes were constructed. In an analysis of the combined cardiogenic and carotid stroke group, both the allele (P=0.0060) and genotype (P=0.0160) frequencies between cases and controls at SNP83 showed significant differences. However, no difference in haplotype frequencies was observed between cases and controls at rs152312 and SNP56. In the analysis of the small-artery-occlusive stroke group, no difference in allele or genotype frequencies was observed at any marker between cases and controls; the global haplotype frequency in rs152312 and SNP56 had a significant difference between cases and controls (P=0.0162); the frequency of haplotype C-A was higher in cases than in controls (P=0.0122). In conclusion, our present findings show that polymorphisms in the PDE4D gene are associated with an increased risk of ischaemic stroke in the Chinese Han population. The present study adds further support to the role of PDE4D in stroke.

[Gene mapping and mutation detection in a family with congenital nuclear cataract].

OBJECTIVE: To map and detect the gene responsible for congenital nuclear cataract in a Chinese family. METHODS: Genomic DNA was extracted from the peripheral blood samples of members of the pedigree. Gene scan was performed using approximately 400 microsatellite markers spaced at about 10 cM intervals (ABI). Linkage analysis was carried out using a Linkage software package. Additional microsatellite markers for the positive region were selected for precise targeting, and haplotype data were processed using Cyrillic software to define the region of the disease gene. Mutation detection was carried out by sequencing candidate genes. RESULTS: Suggestive evidence of linkage was detected at marker D2S325 (LOD score [Z] = 2.29, recombination fraction [theta] = 0.00). Precise targeting and haplotype analysis traced the disease gene to a 19.04 cM region bounded by D2S117 and D2S2382 on chromosome 2q32.3-q35. Direct sequencing of the candidate gene cluster revealed a G-->A transversion in exon 3 of CRYGC. CONCLUSIONS: The present study has identified a novel nonsense mutation in CRYGC associated with congenital nuclear cataracts in a Chinese family.

The E233del mutation in BFSP2 causes a progressive autosomal dominant congenital cataract in a Chinese family.

PURPOSE: Congenital cataract is a fundamental cause of blindness throughout the world. A large multi-generational family in northern China was investigated to determine the genetic cause of a progressive autosomal dominant congenital cataract. METHODS: Slit-lamp photography was conducted to provide definite data for cataract diagnosis. A genome wide scan, linkage analysis, and haplotype analysis were performed to shield the linkage region on the chromosome. BFSP2 was investigated by direct sequencing and detection of fluorescent labeled polymerase chain reaction (PCR) products. RESULTS: Two-point linkage analysis mapped this autosomal dominant congenital cataract (ADCC) locus to D3S1292 in 3q22.1 with a LOD score Zmax=3.99 (theta=0.00). Haplotype analysis located the cosegregating region between marker D3S1551 and D3S3617. In this region, BFSP2 is a powerful candidate gene. Direct sequencing identified the cosegregating E233del mutation in exon 3 of BFSP2. This mutation was not detected in 100 unrelated controls. CONCLUSIONS: The E233del mutation in BFSP2 is the cause of the cataract phenotype in this pedigree. The progressive phenotype has provided more evidence for the heterogeneity of congenital cataract caused by BFSP2 mutations and for the important role BFSP2 plays in cataract formation.

[Genetic analysis of a Chinese pedigree with split hand and foot malformation].

OBJECTIVE: To analyze the clinical manefestation and genetic basis of split hand and foot malformation (SHFM) in a Chinese pedigree. METHODS: The affected people in the family were checked by X-rays. Eighteen patients provided their peripheral blood, and the genomic DNA of the samples was extracted. The linkage and haplotype analysis were carried out using the microsatellite markers, and the limb malformation related gene Dactylin (DAC) including the coding region, exon-intron boundaries and part of promoter region was sequenced. RESULTS: Most members of the family with the disease phenotype showed absence or hypoplasia of the index finger, and absence or 3-4 syndactyly of the middle finger. The degree of abnormality in feet was severer than that in hands. All phenotypes of the patients display the basic characters of SHFM. Since the maximum two point LOD score of the D10S192 was 3.50 (theta=0.00), the SHFM in this pedigree can be categorized to the SHFM3. The haplotype analysis of recombination events revealed the candidate locus to a 21cM region between D10S185 and D10S1693. No mutation was found by the sequencing result of DAC gene. CONCLUSION: Through the analysis of phenotype of the patients, the typical SHFM disease can be confirmed. The linkage and haplotype analysis demonstrated that the 21cM region in 10q23-q26 locus was the major cause to the disease in this pedigree. The mutation of DAC gene can be excluded from cause of SHFM3 phenotype.

Progressive sutural cataract associated with a BFSP2 mutation in a Chinese family.

PURPOSE: To identify the mutation underlying the segregation of progressive sutural congenital cataracts in a four-generation Chinese pedigree. METHODS: Genomic DNA was extracted from the peripheral blood samples of members of the pedigree. A genome-wide scan was performed using microsatellite markers spaced at about 10 cM intervals. Linkage analysis was carried out using a Linkage software package. Ten additional microsatellite markers for the positive region were selected for precise targeting, and haplotype data were processed using Cyrillic software to define the region of the disease gene. Mutation detection was carried out by sequencing candidate genes. RESULTS: Significant evidence of linkage was obtained at marker D3S1279 (LOD score [Z] =2.32, recombination fraction [theta]=0.0). Precise targeting and haplotype analysis traced the disease gene to a 38.6 cM region bounded by D3S1267 and D3S1614 at 3q21.1- q26.2 near BFSP2, which encodes a lens-specific beaded filament protein. Sequencing results revealed a 3-bp deletion of nucleotides 696-698 (GAA) in exon 3 of BFSP2, which is predicted to cause an in-frame deletion of glutamic acid residue 233 from the polypeptide encoded by the mutant gene. This deletion was seen neither in any unaffected member of the family nor in 50 unrelated control individuals. CONCLUSIONS: We observed progressive isolated sutural cataract associated with a deletion mutation of the BFSP2 gene in a Chinese pedigree. It highlights the physiological importance of the beaded filament protein and supports the role of BFSP2 in human cataract formation.

[Mapping of a pedigree with autosomal dominant inherited congenital sutural cataract].

OBJECTIVE: To map the gene responsible for autosomal dominant congenital sutural cataract of a Chinese family. METHODS: Peripheral blood samples were collected from the members in a family with autosomal dominant congenital sutural cataract. The genomic DNA was extracted from the blood samples. A genescan was performed using approximately 400 microsatellite markers (ABI). Linkage analysis was processed by Linkage software package to define the location of mutation gene. High density primers labeled with fluorescent stain for the positive region were adopted for fine targeting, and haplotype analysis was processed using Cyrillic software. RESULTS: The maximum two-point LOD scores was obtained at D3S1279, Z(max) = 2.32 (theta(max) = 0.00). After fine targeting and haplotype analysis, the gene was located within a 38.6 cM region between D3S1267 and D3S1614. CONCLUSION: The gene responsible for congenital sutural cataract in a Chinese pedigree is located at chromosome 3q21.1 - q26.2 within a 38.6 cM region.

[Studies of the cellular biological function of expression change of RAB5A gene in human lung adenocarcinoma GLC-82 and SPC-al].

To determine the effect of RAB5A gene over-expression on invasion and differentiation of Human Lung Adnocarcinoma Cells SPC-al and GLC-82. Using constructed antisense RNA of RAB5A (pcDNA3--AntiRAB5A) and RAB5A eukaryotic expression vector (pcDNA3.1-RAB5A), we stably transfected them into low differentiation human lung adenocarcinoma GLC-82 cell and human lung adenocarcinoma cells SPC-al with low metastasis potential capability respectively in vitro. We observed the change of capability of transfected cells in invading recombinant basic membrane and chemotactic motion experiment in vitro, and we make use of hypodermic method with tumor cells in nude to observe the change of differentiation in transfected GLC-82 cells. The transfected GLC-82 cells with pcDNA3--antiRAB5A showed notable alteration. The capability of invading recombinant basic membrane and chemotatic motion decreased in transfected GLC-82 cells. The differentiation of transfected GLC-82 cells was apparently improved. The array of adenocytes is regular and it appears adenoid structure. After RAB5A eukaryotic expression plasmid was transfected into SPC-al, the invasive activity of cells is increased. Over expression of RAB5A played an important role in invasion and differentiation of human lung adenocarcinoma cells SPC-al and GLC-82.

[The effect of RAB5A gene over-expression on invasive and metastatic capabilities of human lung adenocarcinoma cell lines].

BACKGROUND: Over-expression of RAB5A gene has been proved to be associated with neoplasia metastasis. This study is to explore the effect of RAB5A gene on invasion and metastasis of human lung adenocarcinoma cell lines. METHODS: Constituted basement membrane invasion technique, adhesion capability of tumor cell assay, the chemotactic migration of tumor cells assay, and gelatinases SDS-PAGE analysis method were used to detect the changes of invasive and metastatic capability of Anip973 (with high metastatic capability) and its parent AGZY83-a cell lines (with low metastatic capability). RESULTS: After AGZY83-a cells were transfected by PcDNA3.1-RAB5A plasmid, its invasion was significantly increased (t=24.36, P < 0.000 5); adhesion capability of cell was promoted (P < 0.05); the chemotactic migration of cells was higher than that of the parent lines (t=14.18, P < 0.000 5); and the activity of gelatinases secreted from transfected AGZY83-a was enhanced. The invasion of the transfected Anip973 cells with PcDNA3-AntiRAB5A was lower (t= 16.510 4, P < 0.002 5); adhesion capability of cell was decreased (P < 0.05); the chemotactic migration of cells was lower than that of the parent lines (t=6.062, P < 0.005); and the activity of gelatinases was obviously decreased. CONCLUSIONS: This study in vitro indicates that over-expression of RAB5A genes plays an important role in tumor invasion and metastatic phenotype formation of human lung adenocarcinoma cells; and antisense RNA can interrupt the translation of RAB5A gene.

Study on the inhibitory effect of allicin on human gastric cancer cell line SGC-7901 and its mechanism.

BACKGROUND: Allicin is the main active constituent of Allium sativum L., which is characterized by broad antibacterial spectrum (MarkosN et al., 2008; Chen et al., 2008); it also has apparent inhibitory effects on a variety of tumors. The Objective of the paper is to study the inhibitory effect of allicin on human gastric cancer cell line SGC-7901. MATERIALS AND METHODS: MTT assay and flow cytometry technique were applied to determine the inhibition rate of allicin on human gastric cancer cell line SGC-7901. The results shows that different concentrations of allicin apparently inhibited the gastric cancer SGC7901 cells, cell growth inhibition rates in the experimental groups showed an upward trend with increased allicin concentration, which were concentration-dependent. RESULTS: Flow cytometry results found that the cell cycle was arrested in the G2/M phase. Allicin has an apparent inhibitory effect on proliferation of gastric cancer cells, and can induce their apoptosis. CONCLUSION: Compared with other chemotherapeutic drugs, allicin's anti-tumor effect is better; and toxic and side effects are relatively small.

Identification of duplication downstream of BMP2 in a Chinese family with brachydactyly type A2 (BDA2).

Brachydactyly type A2 (BDA2, MIM 112600) is characterized by the deviation and shortening of the middle phalange of the index finger and the second toe. Using genome-wide linkage analysis in a Chinese BDA2 family, we mapped the maximum candidate interval of BDA2 to a ∼1.5 Mb region between D20S194 and D20S115 within chromosome 20p12.3 and found that the pairwise logarithm of the odds score was highest for marker D20S156 (Zmax = 6.09 at θ = 0). Based on functional and positional perspectives, the bone morphogenetic protein 2 (BMP2) gene was identified as the causal gene for BDA2 in this region, even though no point mutation was detected in BMP2. Through further investigation, we identified a 4,671 bp (Chr20: 6,809,218-6,813,888) genomic duplication downstream of BMP2. This duplication was located within the linked region, co-segregated with the BDA2 phenotype in this family, and was not found in the unaffected family members and the unrelated control individuals. Compared with the previously reported duplications, the duplication in this family has a different breakpoint flanked by the microhomologous sequence GATCA and a slightly different length. Some other microhomologous nucleotides were also found in the duplicated region. In summary, our findings support the conclusions that BMP2 is the causing gene for BDA2, that the genomic location corresponding to the duplication region is prone to structural changes associated with malformation of the digits, and that this tendency is probably caused by the abundance of microhomologous sequences in the region.

Metabolomic analysis reveals metabolic disturbance in the cortex and hippocampus of subchronic MK-801 treated rats.

BACKGROUND: Although a number of proteins and genes relevant to schizophrenia have been identified in recent years, few are known about the exact metabolic pathway involved in this disease. Our previous proteomic study has revealed the energy metabolism abnormality in subchronic MK-801 treated rat, a well-established animal model for schizophrenia. This prompted us to further investigate metabolite levels in the same rat model to better delineate the metabolism dysfunctions and provide insights into the pathology of schizophrenia. METHODS: Metabolomics, a high-throughput investigatory strategy developed in recent years, can offer comprehensive metabolite-level insights that complement protein and genetic findings. In this study, we employed a nondestructive metabolomic approach (1H-MAS-NMR) to investigate the metabolic traits in cortex and hippocampus of MK-801 treated rats. Multivariate statistics and ingenuity pathways analyses (IPA) were applied in data processing. The result was further integrated with our previous proteomic findings by IPA analysis to obtain a systematic view on our observations. RESULTS: Clear distinctions between the MK-801 treated group and the control group in both cortex and hippocampus were found by OPLS-DA models (with R(2)X = 0.441, Q(2)Y = 0.413 and R(2)X = 0.698, Q(2)Y = 0.677, respectively). The change of a series of metabolites accounted for the separation, such as glutamate, glutamine, citrate and succinate. Most of these metabolites fell in a pathway characterized by down-regulated glutamate synthesis and disturbed Krebs cycle. IPA analysis further confirmed the involvement of energy metabolism abnormality induced by MK-801 treatment. CONCLUSIONS: Our metabolomics findings reveal systematic changes in pathways of glutamate metabolism and Krebs cycle in the MK-801 treated rats' cortex and hippocampus, which confirmed and improved our previous proteomic observation and served as a valuable reference to the etiology research of schizophrenia.