Multiple regression analysis of the cholinesterase activity with certain physiochemical factors

Seasonal variation in liver function tests: a time-series analysis of outpatient data

BACKGROUND

Long-term physiological variations, such as seasonal variations, affect the screening efficiency at medical checkups. This study examined the seasonal variation in liver function tests using recently described data-mining methods.

METHODS

The 'latent reference values' of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyltransferase (gammaGT), cholinesterase (ChE) and total bilirubin (T-Bil) were extracted from a seven-year database of outpatients (aged 20-79 yr; comprising approximately 1,270,000 test results). After calculating the monthly means for each variable, the time-series data were separated into trend and seasonal components using a local regression model (Loess method). Then, a cosine function model (cosinor method) was applied to the seasonal component to determine the periodicity and fluctuation range. A two-year outpatient database (215,000 results) from another hospital was also analysed to confirm the reproducibility of these methods.

RESULTS

The serum levels of test results tended to increase in the winter. The increase in AST and ALT was about 6% in men and women, and was greater than that in ChE, ALP (in men and women) and gammaGT (in men). In contrast, T-Bil increased by 3.6% (men) and 5.0% (women) in the summer. The total protein and albumin concentrations did not change significantly. AST and ALT showed similar seasonal variation in both institutions in the comparative analysis.

CONCLUSIONS

The liver function tests were observed to show seasonal variations. These seasonal variations should therefore be taken into consideration when establishing either reference intervals or cut-off values, which are especially important regarding aminotransferases.

Common null variant, Arg192Stop, in a G-protein coupled receptor, olfactory receptor 1B1, associated with decreased serum cholinesterase activity

AIM

Non-functioning single nucleotide polymorphisms (nSNPs) that result in premature termination codons, that is null-alleles of the respective genes, may have phenotypic effects on clinical parameters. We conducted association studies involving several G-protein coupled receptors (GPCRs) that harbor nSNPs, using clinical parameters of liver function in a general population consisting of 2969 Japanese adults.

METHODS

SNP typings were performed with TaqMan and Invader assays. Quantitative associations between genotypes and clinical parameters were analyzed by analysis of variance. Linkage disequilibrium (LD) was tested by Haploview Version 3.3. Haplotype-based association was performed using the haplo.stats program.

RESULTS

A significant correlation (P = 0.0057) was identified between serum cholinesterase activity (CHE) and an nSNP (Arg192Stop) in the olfactory receptor (OR) 1B1 gene, a member of the GPCR gene family. This nSNP was associated with decreased serum CHE (P = 0.0013). LD analysis based on eight selected SNPs at the locus revealed three LD blocks. The Arg192Stop nSNP was located on the second LD block, which covered one-third of the 3'-portion of the gene.

CONCLUSION

These results suggested that the null-allele of OR1B1 might affect metabolism of serum cholinesterase in carriers of this nSNP.

Proteome Analysis of Responses to Ascochlorin in a Human Osteosarcoma Cell Line by 2-D Gel Electrophoresis and MALDI-TOF MS

Ascochlorin is a prenyl-phenol compound that was isolated from the fungus Ascochyta viciae. Ascochlorin reduces serum cholesterol and triglyceride levels, suppresses hypertension and tumor development, and ameliorates type I and II diabetes. Here, to better understand the mechanisms by which ascochlorin regulates physiological or pathological events and induces responses in the pharmacological treatment of cancer, we performed differential analysis of the proteome of the human osteosarcoma cells U2OS in response to ascochlorin. In addition, we established the first two-dimensional map of the U2OS proteome. The U2OS cell proteomes with and without treatment with ascochlorin were compared using two-dimensional electrophoresis, matrix-assisted laser desorption/ionization mass spectrometry and bioinformatics. The largest differences in expression were observed for the epidermal growth factor receptor (4-fold decrease), ribulose-5-phosphate-epimerase (13-fold decrease), ATP-dependent RNA helicase (8-fold decrease), and kelch-like ECH-associated protein 1 (6-fold decrease). The abundance of heterogeneous nuclear ribonucleoprotein L and minichromosome maintenance protein 7 increased 12- and 8.2-fold, respectively. In addition, Erk 2 was increased 3-fold in U2OS cells treated with ascochlorin. The expression of some selected proteins was confirmed by western blotting, zymography and RT-PCR analysis.

Ascochlorin Inhibits Matrix Metalloproteinase-9 Expression by Suppressing Activator Protein-1-mediated Gene Expression through the ERK1/2 Signaling Pathway

The expression of matrix metalloproteinases (MMPs) has been implicated in the invasion and metastasis of cancer cells. Here we examined the effect of ascochlorin, a prenyl-phenol anti-tumor compound from the fungus Ascochyta viciae, on the regulation of signaling pathways that control MMP-9 expression in human renal carcinoma (Caki-1) cells. Ascochlorin reduced the invasive activity of Caki-1 cells and inhibited phorbol 12-myristate 13-acetate-induced increases in MMP-9 expression and activity in a dose-dependent manner. Reporter gene, electrophoretic mobility shift, kinase inhibitor assays, and in vitro kinase assay showed that ascochlorin inhibits MMP-9 gene expression by suppressing activation of the nuclear transcription factor activator protein-1 (AP-1) via the extracellular signal-regulated kinase 1 and 2 pathway. The AP-1 family member most specifically affected by ascochlorin was Fra-1. Ascochlorin did not affect the activation of the c-Jun N-terminal or p38 kinase pathways. Moreover, transfection of Caki-1 cells with AP-1 decoy oligodeoxynucleotides resulted in the suppression of phorbol 12-myristate 13-acetate-induced MMP-9 expression and invasion. In conclusion, ascochlorin represents a unique natural anti-tumor compound that specifically inhibits MMP-9 activity through suppression of AP-1-dependent induction of MMP-9 gene expression.