1Prog. Neuropsychopharmacol. Biol. Psychiatry 2009 Nov 33: 1491-5
PMID19703508
TitlePositive association between ALDH1A2 and schizophrenia in the Chinese population.
AbstractVitamin A (retinol), in the biologically active form of retinoic acid (RA), has been proposed as involved in the pathogenesis of schizophrenia. We hypothesized that genetic basis of genes encoding RA metabolism enzymes, which control the cellular RA level, might be associated with this disease. This cascade genetic association model, using markers in genes of synthesis and degradation enzymes within the retinoid cascade, would better fit the biological character of the retinoid hypothesis than the single gene strategy. In the present study we chose to investigate 7 genes involved in the synthesis, degradation and transportation of RA, ALDH1A1, ALDH1A2, ALDH1A3, CYP26A1, CYP26B1, CYP26C1 and Transthyretin (TTR), for their roles in the development of schizophrenia. We genotyped 18 single nucleotide polymorphisms (SNPs) in the regulatory and coding regions of these 7 genes using LDR technology in the 617 Chinese Han subjects. Case-control analyses were performed to detect association of these 7 genes with schizophrenia. Association analyses using both allelic and genotypic single-locus tests revealed no significant association between the risk for each of investigated gene and schizophrenia. However, analyses of multiple-locus haplotypes indicated that the overall frequency of rs4646642-rs4646580 of ALDH1A2 gene showed significant difference between patients and control subjects (p=0.0055). We also employed multifactor dimensionality reduction method to detect multilocus effects. In summary, in this work we show multiple candidate genes involved in retinoid cascade in schizophrenics. In addition, our results suggest a positive association between ALDH1A2 and schizophrenics in the Chinese population and support the retinoid hypothesis of schizophrenia.
SCZ Keywordsschizophrenia, schizophrenics
2Prog. Neuropsychopharmacol. Biol. Psychiatry 2009 Nov 33: 1491-5
PMID19703508
TitlePositive association between ALDH1A2 and schizophrenia in the Chinese population.
AbstractVitamin A (retinol), in the biologically active form of retinoic acid (RA), has been proposed as involved in the pathogenesis of schizophrenia. We hypothesized that genetic basis of genes encoding RA metabolism enzymes, which control the cellular RA level, might be associated with this disease. This cascade genetic association model, using markers in genes of synthesis and degradation enzymes within the retinoid cascade, would better fit the biological character of the retinoid hypothesis than the single gene strategy. In the present study we chose to investigate 7 genes involved in the synthesis, degradation and transportation of RA, ALDH1A1, ALDH1A2, ALDH1A3, CYP26A1, CYP26B1, CYP26C1 and Transthyretin (TTR), for their roles in the development of schizophrenia. We genotyped 18 single nucleotide polymorphisms (SNPs) in the regulatory and coding regions of these 7 genes using LDR technology in the 617 Chinese Han subjects. Case-control analyses were performed to detect association of these 7 genes with schizophrenia. Association analyses using both allelic and genotypic single-locus tests revealed no significant association between the risk for each of investigated gene and schizophrenia. However, analyses of multiple-locus haplotypes indicated that the overall frequency of rs4646642-rs4646580 of ALDH1A2 gene showed significant difference between patients and control subjects (p=0.0055). We also employed multifactor dimensionality reduction method to detect multilocus effects. In summary, in this work we show multiple candidate genes involved in retinoid cascade in schizophrenics. In addition, our results suggest a positive association between ALDH1A2 and schizophrenics in the Chinese population and support the retinoid hypothesis of schizophrenia.
SCZ Keywordsschizophrenia, schizophrenics
3J Biochem Pharmacol Res 2013 Dec 1: 228-235
PMID24494173
TitleHomozygous Deletion of Glutathione Peroxidase 1 and Aldehyde Dehydrogenase 1a1 Genes Is Not Associated with Schizophrenia-Like Behavior in Mice.
AbstractMuch evidence suggests that oxidative stress plays a role in schizophrenia pathogenesis. Major oxidative stress sources include hydrogen peroxide and biogenic aldehydes that are mainly cleared in vivo by glutathione peroxidase (GPX) and aldehyde dehydrogenase (ALDH), respectively. Both enzymes are richly expressed in brain. schizophrenia patients have significantly increased plasma levels of malondialdehyde and glutathione, combined with decreased GPX activity and ALDH1 mRNA levels in the ventral tegmental area. Absence of ALDH1A1 (murine homolog of ALDH1) gene causes increased basal extracellular dopamine concentrations, a common characteristic of schizophrenia. Studies investigating association between gene polymorphisms of GPX1 (the most abundant form of GPX) or ALDH1A1 with schizophrenia also have not clearly demonstrated whether ALDH1A1 or GPX1 is involved in pathogenesis of schizophrenia. To investigate possible contributions of ALDH and GPX to pathological behaviors associated with schizophrenia, we generated mice with both ALDH1A1 and Gpx1 gene deletions (KO). ALDH1A1/Gpx1 KO and wild type (WT) mice had similar number of novel entry and alteration in Y-maze test, suggesting no cognition deficit in KO. Furthermore, KO and WT displayed similar social interaction and novelty preferences in three chambered tests. Overall, KO and WT had similar activity levels, as indicated by their entries in the Y-maze and sociability tests. Furthermore both genotypes buried a similar percentage of marbles in a 30 min marble-burying task. In summary, homozygous deletion of Gpx1 and ALDH1A1 genes was not associated with schizophrenia-like behavioral phenotypes including anxiety, hyperactivity, cognitive deficit or social disability. Our findings suggest that constitutive absence of these genes alone is unlikely to give rise to common behavioral schizophrenia symptoms. However, these mice may be highly sensitive to oxidative challenges during critical stages of prenatal or juvenile brain development.
SCZ Keywordsschizophrenia, schizophrenics
4Schizophr. Res. 2016 May -1: -1
PMID27236410
TitleAltered CSNK1E, FABP4 and NEFH protein levels in the dorsolateral prefrontal cortex in schizophrenia.
Abstractschizophrenia constitutes a complex disease. Negative and cognitive symptoms are enduring and debilitating components of the disorder, highly associated to disability and burden. Disrupted neurotransmission circuits in dorsolateral prefrontal cortex (DLPFC) have been related to these symptoms. To identify candidates altered in schizophrenia, we performed a pilot proteomic analysis on postmortem human DLPFC tissue from patients with schizophrenia (n=4) and control (n=4) subjects in a pool design using differential isotope peptide labelling followed by liquid chromatography tandem mass spectrometry (LC-MS/MS). We quantified 1315 proteins with two or more unique peptides, 116 of which showed altered changes. Of these altered proteins, we selected four with potential roles on cell signaling, neuronal development and synapse functioning for further validation: casein kinase I isoform epsilon (CSNK1E), fatty acid-binding protein 4 (FABP4), neurofilament triplet H protein (NEFH), and retinal dehydrogenase 1 (ALDH1A1). Immunoblot validation confirmed our proteomic findings of these proteins being decreased in abundance in the schizophrenia samples. Additionally, we conducted immunoblot validation of these candidates on an independent sample cohort comprising 23 patients with chronic schizophrenia and 23 matched controls. In this second cohort, CSNK1E, FABP4 and NEFH were reduced in the schizophrenia group while ALDH1A1 did not significantly change. This study provides evidence indicating these proteins are decreased in schizophrenia: CSNK1E, involved in circadian molecular clock signaling, FABP4 with possible implication in synapse functioning, and NEFH, important for cytoarchitecture organization. Hence, these findings suggest the possible implication of these proteins in the cognitive and/or negative symptoms in schizophrenia.
SCZ Keywordsschizophrenia, schizophrenics