No involvement of the adenosine A2A receptor in tardive dyskinesia in Russian psychiatric inpatients from Siberia
ABSTRACT The adenosine A2A receptor forms a heteromeric complex with the striatal dopamine D2 receptor. We examined whether a specific polymorphism in adenosine A2A receptor (2592 C/Tins) is associated with tardive dyskinesia.
Tardive dyskinesia was assessed cross-sectionally in 146 Caucasian psychiatric inpatients from Siberia.
Between-group comparisons of genotypic or allelic frequencies showed no statistically significant difference. Logistic regression analysis with the occurrence of tardive dyskinesia as dependent variable showed no significant association with age, duration of illness, gender, and genotype.
The interaction between the A2A and D2 receptors seems not involved in the development of tardive dyskinesia.
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ABSTRACT: PURPOSE OF REVIEW: Antipsychotic drugs are effective in alleviating a variety of symptoms and are medication of first choice in schizophrenia. However, a substantial interindividual variability in side effects often requires a lengthy 'trial-and-error' approach until the right medication is found for the right patient. Genetic factors have long been hypothesized to be involved and identification of related gene variants could be used to predict and tailor drug treatment. RECENT FINDINGS: This review highlighting the most recent genetic findings was conducted on the two most common and most well-studied side effects: antipsychotic-induced weight gain and tardive dyskinesia. SUMMARY: Regarding weight gain, most promising and most consistent findings were obtained in the serotonergic system (HTR2C) and with hypothalamic leptin-melanocortin genes, in particular with one variant close to the melanocortin-4-receptor (MC4R) gene. With respect to tardive dyskinesia, most interesting findings were generally obtained in genes related to the dopaminergic system (dopamine receptors D2 and D3), and more recently with glutamatergic system genes. Overall, genetic studies have been successful in identifying strong findings, in particular for antipsychotic-induced weight gain and to some extent for tardive dyskinesia. Apart from the need for replication studies in larger and well-characterized samples, the next challenge will be to create predictive algorithms that can be used for clinical practice.Current opinion in psychiatry 03/2013; 26(2):144-150. DOI:10.1097/YCO.0b013e32835dc9da · 3.55 Impact Factor
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ABSTRACT: Tardive dyskinesia (TD) is a potentially irreversible consequence of long term treatment with antipsychotic drugs which is according to a well-known theory believed to be related to oxidative stress induced neurotoxicity. Dehydroepiandrosterone (DHEA) is an endogenous antioxidant with neuroprotective activity. The biosynthesis of DHEA depends upon the activity of cytochrome P450c17α (CYP17). The gene that encodes for CYP17 has a (T34C) single nucleotide polymorphism which enhances CYP17 transcription and expression. To test the hypothesis that carriership of a more active CYP17 variant would result in higher DHEA(S) levels and protect against neurotoxicity which results in orofaciolingual TD (TDof), limb-truncal TD (TDlt) or both (TDsum)? Tardive dyskinesia was assessed cross-sectionally in 146 Caucasian psychiatric inpatients from Siberia. Patients who are carriers of the Cyp17 genotype CC have less chance of developing TD compared to patients who are carriers of the Cyp17 genotypes TC or TT (p<0.05). However, these carriers have significant lower circulating DHEAS levels compared to carriers of the Cyp17 genotypes TC and TT (p<0.05). Conversely, carriers of the CYP17 T-allele have significant elevated DHEAS levels. After correcting for gender and age no significant relationship between Cyp17 genotype CC, the T-allelle and the C-allele and the DHEAS concentration of patients was observed. Conclusions: Although an association between the CYP17 CC genotype and TD is indicated, our findings do not support the hypothesis that this is mediated through increased DHEA(S) levels. We believe that the relationship between this polymorphism and neuroprotective effects of steroids is more complex and cannot be elucidated without taking the posttranslational regulation of the enzyme into account.Progress in Neuro-Psychopharmacology and Biological Psychiatry 01/2014; DOI:10.1016/j.pnpbp.2013.12.015 · 4.03 Impact Factor