[Deletion polymorphism of GSTT1 gene and lipid peroxidation hyperactivation in menopausal insomnia]

A comparative analysis of the parameters of lipid peroxidation - antioxidant defense system in menopausal women with- and without insomnia, depending on the GSTT1 polymorphism.

The study included 181 menopausal Caucasian women (ethnic group - Russians), who according to the results of the clinical-anamnestic examinations were divided into insomnia group (n=120, age 53.68±4.61 years, body mass index 26.47±3.73 kg/m²) and control group (n=61, age 52.64±4.91 years, body mass index 27.69±3.11 kg/m²). The insomnia group was formed according to the clinical guidelines for the diagnosis and treatment of chronic insomnia in adults, and scores of the Insomnia Severity Index. The study of the GSTT1 gene polymorphism was carried out using polymerase chain reaction. The lipid peroxidation - antioxidant system parameters were determined by spectrofluorophotometric methods.

In the insomnia group, carriers of the normal GSTT1 genotype had higher diene conjugates with lower glutathione peroxidase activity as compared to controls. When comparing groups of women with the deletion in GSTT1, an increase in the content of substrates and lipid peroxidation products was observed at all stages of lipid peroxidation, oxidized glutathione, glutathione S-transferase activity with a decrease in the content of reduced glutathione and retinol in the insomnia group as compared to controls. In the insomnia group, carriers of the deletion genotype had a higher content of ketodienes/conjugated trienes and active products of thiobarbituric acid, a lower content of retinol and α-tocopherol as compared to the patients with normal GSTT1 genotype. Conclusions. Insomnia in the menopausal women is accompanied with the intensification of lipid peroxidation only in the carriers of the GSTT1 deletion genotype.