[Coherence of the electroencephalogram and peripheral markers of nerve tissue damage in depressive disorders]

OBJECTIVE

To evaluate the coherence parameters of the electroencephalogram and the level of peripheral markers of nerve tissue damage in patients with depressive disorders.

MATERIAL AND METHODS

Thirty patients with a diagnosis from a cluster of mood disorders: affective disorder within a single depressive episode and recurrent depressive disorder were examined. A control group consisted of 30 healthy individuals, comparable in sex and age to the main group. The bioelectric activity of the brain was recorded and analyzed with the calculation of the averaged coefficients of intra- and interhemispheric coherence. The concentration of calcium-binding protein S100b, the main protein of myelin MBP and glial fibrillar acid protein GFAP was determined in blood sera by solid-phase enzyme immunoassay.

RESULTS

Patients with depressive disorders showed signi cantly lower coefficients of interhemispheric coherence of alpha (p=0.003), beta (p=0.042) and theta rhythms (p=0.041), as well as intrahemispheric coherence of alpha rhythm in the left (p=0.016) and right hemispheres (p=0.026), beta rhythm in the right hemisphere (p=0.034) compared to the control group. Patients with depressive disorders showed a higher concentration of MBP compared to the control group (p=0.008). Additionally, we identified statistically significant correlations between EEG coherence coefficients and serum markers in patients with depressive disorders.

CONCLUSION

The results clearly confirm the presence of inflammatory changes in the brain in patients with depression, which is reflected in structural and functional changes.

Executive dysfunction in affective disorders: differences in bipolar affective disorder and depressive episode

Aim. To identify the differences in executive function (inhibitory control, working memory, cognitive flexibility) between patients with bipolar affective disorder and depressive episode.

Materials and methods. A total of 72 patients with affective disorders aged 20–40 years were examined. Of them, 30 patients had bipolar affective disorder, a current episode of mild or moderate depression, and 42 patients had a mild, moderate, and severe depressive episode without symptoms of psychosis. The executive function was evaluated using PsyToolkit, a set of software tools for programming psychological experiments. Computerized Go/ No–go tasks (assessment of inhibitory control and psychomotor functions), the Corsi block-tapping test (assessment of visual and spatial working memory capacities), and the Stroop Color and Word Test (assessment of cognitive flexibility) were used.

Results. An intergroup comparison of patients revealed that patients with bipolar disorder significantly more often demonstrated false button press in the Go/No–go task (p = 0.043); however, they exhibited a greater working memory capacity in the Corsi block-tapping test (p = 0.049) compared with patients with a depressive episode.

Conclusion. Important data were obtained regarding the specifics of executive dysfunction depending on the type of affective disorder. The presented data expand and supplement available information about the cognitive characteristics of patients with bipolar affective disorder and depressive episode, which may be useful in clinical practice and serve a focus of future research.

[Association of polymorphic variants of PIP5K2A and HTR2C genes with response to antidepressant therapy of patients with a current depressive episode]

AIM

To study the association between polymorphisms of PIP5K2A and HTR2C genes and response to antidepressant therapy in patients with a current depressive episode.

MATERIAL AND METHODS

The study included 222 patients (168 women and 54 men) with a current depressive episode. The assessment of the severity of the current depressive episode and the efficacy of treatment was performed using the Hamilton depression scale (HDRS-17) and the Clinical global impression scale (CGI-S, CGI-I). The association of treatment efficacy with PIP5K2A polymorphisms rs10430590, rs10828317 and HTR2C polymorphisms rs6318, rs569959, rs3813929, rs12858300 was studied.

RESULTS AND CONCLUSION

Polymorphisms rs10828317 and rs10430590 in the PIP5K2A gene were associated with the CGI-S total score at day 28 of therapy. Polymorphism rs6318 in the HTR2C gene was associated with response to antidepressant therapy followed by clinical improvement of patients with current depressive episode on the 28th day of antidepressant therapy.

Signs of apoptosis of immunocompetent cells in patients with depression

A total of 26 patients with depression and 20 healthy subjects were studied. Measures of apoptosis of peripheral blood lymphocytes and serum cortisol concentrations were determined. A significant increase in lymphocyte apoptosis was found in patients with depression, resulting in an increase in the proportion of lymphocytes expressing the FAS receptor; cells with morphological signs characteristic of apoptosis (nuclear condensation, vacuolization) were also seen. Changes in cellular immunity were observed on the background of clinical depressive symptomatology, with decreases in the total numbers of T-lymphocytes (CD3(+)), T-helpers (CD4(+)), and natural killer cells (CD16(+)) as compared with numbers in healthy subjects. Serum cortisol levels were elevated. Correlation analysis revealed an interaction between high cortisol levels and decreases in T-helper cells (CD4(+)) and increases in apoptosis receptor expression in patients with depressive disorder.

[Apoptosis of immunocompetent cells in patients with depressive disorders]

A comprehensive evaluation of biological indices has been carried out in 26 patients with depressive disorders and in 20 age- and sex-matched controls. Indices of programmed cell death (apoptosis) in subpopulations of blood lymphocytes and concentration of cortisone in blood serum were determined. Significantly enhanced apoptosis was observed in the lymphocytes of depressive patients as shown by increased percentage of lymphocytes expressing FAS-receptor and cells with morphological changes characteristic of apoptosis (nuclear condensation, vacuolation. Clinical symptoms of depression were concomitant with alterations of cellular link of immunity expressing in the decrease of the total T-lymphocytes (CD3+) number, T-helpers (CD4+) and natural killers (CD16+) as compared to healthy persons. The level of blood serum cortisone was increased in patients with depression. High cortisone values correlated with suppression of cellular CD4+ population and an increase of FAS-receptors expression in patients with depression.