The role of thrombocyte serotonin system and some thrombocyte characteristics in treatment of depressive patients with cardiovascular diseases

Abstract

-Serotonin has an important role in the development of depressive disorders. Bearing in mind that direct testing of central nervous system is unavailable to researchers due to the inability to reach the samples, ever greater attention is given to the peripheral systems that can help us diagnose and detect changes of the disease, but also follow the course of its treatment and recovery. Thrombocyte is a blood cell that contains serotonin lodged in its delta granules. Thrombocyte serotonin system is similar, although not the same as the serotonin system in central nervous system. The most important differences are that in thrombocytes, serotonin is broken down by the enzyme monoaminooxidase B (MAO-B), while that function in neuron is carried out by monoaminooxidase A (MAO-A) and that a thrombocyte cannot synthetize serotonin itself, because it lacks tryptophan hydroxylase. Nowadays, in the treatment of depressive disorders, mostly the selective inhibitors of serotonin uptake (SIPPS) are being used. The research has proved that therapy with those medications changes the concentration of serotonin in thrombocytes and changes the values of some thrombocyte indices. The thrombocyte serotonin is a powerful vasoconstrictor, which increases the cardiovascular risk and the probability of thrombogenesis. The mean volume of thrombocytes (MPV) is a positive index of thrombocyte activity and the increase of MPV represents an independent risk factor for the development of cardiovascular diseases. It is of enormous significance to recognize the depression in patients who suffer from cardiovascular diseases. Depression interferes with the recovery of those patients, because it reduces the personal engagement in it and disturbs patients' compliance and the motivation for treatment. Besides the fact that the treatment with SIPPS leads to the regression of symptoms of depression, it also changes the concentration of thrombocyte serotonin and the mean volume of thrombocytes towards the values that reduce their role in pathogenesis of cardiovascular diseases, thus reducing the risk of re-occurrence of cardiovascular incidents and improving the patients' recovery.

Analysis of cytokine levels, T regulatory cells and serotonin content in patients with depression

“…The platelet 5‐HT system bears some similarities to the serotonergic synapses in the CNS with regard to the storage, accumulation, and release of 5‐HT (Stahl, 1977). In spite of those similarities, these two systems differ concerning metabolizing enzymes, and platelets are not competent to synthesize 5‐HT because of the absence of tryptophan hydroxylase (Kostanjšak & Zdunić, 2017; Stahl, 1985). In consideration of psychopathology, previous studies have shown lower 5‐HT levels in the platelets of patients suffering from depression (Kostanjšak & Zdunić, 2017; Maurer‐Spurej et al., 2004).…”

Correlation Between Salivary Biochemical Stress Indicators and Psychological Indicators

“…Many factors such as neuropeptides, neurotransmitters, opioids, growth factors, cytokinesis, adipokinesis, and battery ligands modulate the release of adrenal glucocorticoids independently of pituitary adrenocorticotropic hormone (ACTH) ( 13 ). Adrenal cortisol release during circadian ascension and stress response are under the control of ACTH and preganglionic sympathetic neurons ( 12 , 14 ).…”

Mood configurations and their relationship to immune system responses: Exploring the relationship between moods, immune system responses, thyroid hormones, and social support

“…Thrombocytes are reported to produce mood-modulating serotonin. Thrombocytes and basophilic granulocytes cell counts are known to be associated with positive and negative moods via histamine and serotonin interactions [8, 44]. In addition, thrombocyte cell count is also found to be related to mood disorders such as bipolar affective disorder [6, 45].…”