angiotensin-i and Schizophrenia

This study aimed at evaluating changes in the renin-angiotensin system (RAS) in patients with schizophrenia in comparison with controls. Plasma levels of angiotensin-converting enzyme (ACE), ACE2, angiotensin (Ang)-(1-7) and Ang II were assessed in 25 patients with schizophrenia and 20 controls. Patients with schizophrenia presented decreased levels of ACE compared to controls [median (25th-75th percentiles) = 434.79 (341.15-524.02) vs. 508.49 (396.34-608.72); p < 0.05]. No significant differences were found regarding ACE2, Ang-(1-7) and Ang II levels. There were no associations between the measured molecules and clinical parameters. Our results corroborate the hypothesis that the RAS is involved in the pathophysiology of schizophrenia.

Topics: Adult; Angiotensin I; Angiotensin II; Angiotensin-Converting Enzyme 2; Female; Humans; Male; Middle Aged; Peptide Fragments; Peptidyl-Dipeptidase A; Schizophrenia

Due to its role in dopamine system functioning in brain, angiotensin-1-converting enzyme (ACE) gene insertion-deletion (I/D) polymorphism is reportedly studied for association with major psychosis. The present study aimed at searching for I/D allele and genotype distribution in patients with major psychosis and healthy subjects and for an association between ACE gene polymorphism and clinical presentations of these disorders. One hundred and ninety-eight patients with schizophrenia (144) and affective disorders (54), 100 male, aged 36.3 +/- 12.8 years, and 247 controls, 87 male, aged 49.6 +/- 13.5 years, have been genotyped. No association was found between ACE gene polymorphism and major psychosis. In the group of males with schizophrenia, genotype distribution differed significantly from that in the male control group (chi2 = 6.24; p = 0.04), with frequencies of the DD genotype and the D allele being higher comparing to the II genotype and the I allele frequency (p = 0.04 and p = 0.01 respectively). It is suggested that in schizophrenia as well as in some other polygenic diseases ACE gene polymorphism might be rather considered as a modifying than a causal factor.

Topics: Adult; Alleles; Angiotensin I; DNA Transposable Elements; Dopamine; Female; Gene Deletion; Humans; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Psychotic Disorders; Schizophrenia

Elevated cerebrospinal fluid (CSF) angiotensin I-converting enzyme (ACE) levels have been evidenced in patients with schizophrenia who have been treated with antipsychotics. In order to explore a possible mononuclear cell origin of CSF ACE, the authors determined CSF ACE and CSF mononuclear cell counts from 25 acutely psychotic patients, who had been drug-free for at least 4 months but started on conventional antipsychotic medication within a few days before sampling. No correlations were found between CSF to serum ACE ratio and CSF mononuclear cell counts. However, CSF total mononuclear cell count, CSF lymphocyte count, and CSF mononuclear phagocyte count evidenced significant positive correlations with current dose of antipsychotic medication expressed as chlorpromazine equivalents. The authors conclude that no indication of a relationship between mononuclear cells and CSF ACE activity was found. Surprisingly, a relationship between chlorpromazine dose and CSF mononuclear cell counts was found, which may indicate drug-related changes in cell-mediated immunity. This finding needs replication and further corroboration in well-designed studies.

Topics: Acute Disease; Adult; Angiotensin I; Antipsychotic Agents; Chlorpromazine; Cross-Sectional Studies; Dose-Response Relationship, Drug; Female; Haloperidol; Humans; Immunity, Cellular; Lymphocytes; Macrophages; Male; Middle Aged; Peptidyl-Dipeptidase A; Psychotic Disorders; Sampling Studies; Schizophrenia; Therapeutic Equivalency