The P-glycoprotein (Pgp, ABCB1-protein) is a transport protein localized in the membrane of hepatocytes, small and large intestine enterocytes, renal tubular epitheliocytes, endothelial cells of histohematic barriers, and tumor cells.

Aim — to study the effect of estradiol and progesterone physiological concentrations on the Pgp functional activity on the whole body.

Material and methods. The work was performed on 17 adult female chinchilla rabbits. The first group of rabbits underwent a “false operation” (n=5); the second group (n=6) underwent ovariectomy. The third group (n=6) was ovariectomized and received estradiol (0.5 mg/rabbit) for 14 days (starting on the 14^th postoperative day), followed by combined administration of estradiol (0.5 mg/rabbit) and progesterone (5 mg/rabbit) for 14 days. The Pgp functional activity was determined in rabbits of all groups using HPLC analysis of fexofenadine pharmacokinetics on day 7 before the study onset and on day 14, 28, and 42 after the operation. Accumulation of fexofenadine in rabbits indicates Pgp inhibition, and a decrease in its content means Pgp induction.

Results. Ovariectomy led to a decrease in the Pgp functional activity. The estradiol introduction for 14 days after ovariectomy did not significantly affect the transport protein functional activity. Combined administration of estradiol and progesterone for 14 days resulted in an increase in the Pgp activity, compared to that in the ovariectomy series and baseline values.

Conclusions. The dependence of the transport protein activity on the dynamics of physiological estradiol and progesterone concentrations suggests that the effectiveness of pharmacotherapy with Pgp substrates may depend on the menstrual cycle phase, and drug dose correction may be used to increase the pharmacotherapy effectiveness.

The problem of the influence of self on human behavior is one of the major focuses of psychologists. However, the problem of self-identification of patients with somatic diseases, in particular type 1 diabetes mellitus, still remains poorly understood.

Aim: the study aim was to investigate the characteristics of self-evaluation in young patients with type 1 diabetes mellitus.

Material and methods. The theoretical and methodological basis of the study was the concept by V.V. Stolin (1985) and the theory of self by S.R. Pantileev (1989). We used the self-attitude assessment (SAA) method by S.R. Pantileev, personal differentia method adapted at the Bekhterev Research Institute; and self-esteem scale test by M. Rosenberg. The study included 60 subjects allocated into two groups: 30 patients with type 1 diabetes mellitus, a mean age of 22.5 years (18 to 25 years) and a mean disease duration of 5 years; 30 healthy subjects with a mean age of 21.5 years (18 to 25 years).

Results. Patients with type 1 diabetes, unlike healthy subjects, had a low level of self-evaluation; they had the most pronounced negative emotional attitude to their Self, which reflected a low level of self-acceptance and comprise. Patients with type 1 diabetes had the level of self-esteem lower than that in healthy subjects. They were characterized by the presence of internal conflicts, disagreement with oneself, and excessive soul-searching and reflection. They considered themselves as the source of their failures.

Conclusions. The results indicate the distinct differences in the structure of Self between type 1 diabetes patients and healthy subjects.

The steroidogenic acute regulatory protein (StAR) is crucial for transport of cholesterol to mitochondria where biosynthesis of steroids is initiated. Loss of StAR function due to autosomal-recessive mutations in the STAR gene leads to lipoid congenital adrenal hyperplasia (LCAH) which is characterized by impaired synthesis of adrenal and gonadal steroids, which causes adrenal insufficiency, primary ovarian failure in 46XX patients, or 46XY disorder of sex development (DSD). However, there were a few reports of 46 XY DSD patients with LCAH caused by a heterozygous mutation in the STAR gene. Here, we describe another rare case of LCAH in a 46XY patient with DSD and primary adrenal insufficiency due to an autosomal-dominant mutation in the STAR gene.

Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) is an autosomal recessive mitochondrial fatty acid beta-oxidation disorder with variable presentation including lack of energy (lethargy), low blood sugar (hypoglycemia), weak muscle tone (hypotonia), hepatic steatosis, and hypocarnitinemia. In this report, we describe a 9-month-old male patient who suffered from recurrent hypoglycemia with hypoglycemic convulsions, vomiting, and neurological regression since the age of 4 months. The patient presented with hypotonia, motor delay, hepatomegaly, protein-energy malnutrition (BMI SDS — 2.8). Biochemical tests demonstrated hypoglycemia (2.5 mmol/l), elevated lactate, creatine phosphokinase, and aminotransferases. There were also increased concentrations of long-chain acylcarnitine and 3-hydroxyacylcarnitine as well as a dramatic decrease in the carnitine level. Digestive tract malformations, endocrinopathies, and degenerative diseases of the nervous system were excluded hydroxyacyl-CoA dehydrogenase (HADHA) gene)testing revealed a homozygous mutation p.Glu474Gln. This confirmed the diagnosis of long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency. Diet correction by adding medium chain triglycerides, compensation of carnitine deficiency, and symptomatic therapy made it possible to avoid fatal metabolic crises and manage neurological regression. Early detection, diagnosis, and treatment of long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency may improve clinical outcomes.

Primary hyperparathyroidism (PHPT) is well studied in elderly patients. Studies of PHPT characteristics in children, adolescents, and young adults are rare. In some of these studies, investigators have compared clinical and laboratory characteristics of PHPT between young and elderly patients and revealed several differences. An early onset of PHPT may indicate familial syndromes associated with PHPT. These include: multiple endocrine neoplasia syndrome type 1, type 2A, and type 4, hyperparathyroidism-jaw tumor syndrome, familial hypocalciuric hypercalcemia, and familial isolated hyperparathyroidism. However, the need for routine genetic tests to exclude these syndromes in all patients with PHPT manifested at a young age is not obvious. To date, there are a few foreign studies on the need for genetic testing in all young patients with PHPT, but their results are controversial. Our review summarizes the data of foreign and Russian studies on characteristics of PHPT in patients with disease onset at a young age.

The strategy for elimination of iodine deficiency in the population was developed and implemented in the Republic of Belarus. It is based on acceptance of recommendations that iodized salt is a unique source of iodine support. Currently, adequate iodine consumption is achieved. The prevalence of thyroid gland diseases caused by iodine deficiency was significantly decreased. In 2013, the International Council for Control of Iodine Deficiency Disorders (ICCIDD), a global non-profit non-governmental organization established to eliminate iodine deficiency and its negative consequences, published the results of iodine status assessment in the world. According to these data, the Republic of Belarus provides adequate iodine intake. In 2016, Iodine Global Network published maps characterizing iodine supply for the two main categories — school-age children and pregnant females. These data have confirmed that the Republic of Belarus refers to countries with sufficient iodine consumption according to the results of subnational studies. Despite the achieved successes, new issues are raised: quality of iodine sufficiency monitoring, risks of excessive salt intake, and need for new approaches to diagnosing thyroid pathology due to iodine deficiency.

Type 2 diabetes mellitus is an urgent problem of the modern healthcare. Despite a wide choice of oral hypoglycemic drugs, today there is a great need to create and introduce into clinical practice new, effective, and safe drugs for the treatment of diabetes. One of the promising targets for the creation of new antidiabetics is a glucokinase. It has an exceptionally high influence on glucose homeostasis, serving as a glucose “sensor” in pancreatic β-cells and controlling the rate of glycogen synthesis in the liver. In the present work, the molecular-genetic structure of the enzyme, as well as its interrelation with the organs and tissues of the organism, is presented. The modern ideas about activators of glucokinase as a promising class of antidiabetic drugs are outlined, their hypoglycemic and general antidiabetic effects proved in preclinical and clinical studies are considered. The most advanced activators of glucokinase, undergoing clinical trials, are indicated.

Diabetic polyneuropathy is one of the most common late complications of diabetes mellitus, as well as the main cause of ulcerative foot defects. The prevalence of neuropathy among people with diabetes varies from 28 to 65%, depending on the disease duration and diagnostic features. Initial signs of damage are detected as early as in prediabetes. To date, there is a fairly limited knowledge of the mechanisms of nerve fiber damage in diabetes. Also, it is unclear which type of nerve fibers is involved in damage first and how the nervous system regulates repair of tissues and local immunity. Animal models of diabetic peripheral neuropathy enable studying new aspects of the pathogenesis of this common diabetes complication and open prospects for the search and development of new drugs.