Search

The Wnt/β signaling pathway (Wnt-SP) is a phylogenetically ancient mechanism that regulates development and maintains tissue homeostasis through the control of cell proliferation, differentiation, migration, and apoptosis. The accurate regulation of the canonical Wnt/β-catenin signaling pathway (Wnt-SP) is critical for embryogenesis and postnatal development; and impaired signal transduction at one of its stages leads to various diseases, including organ malformations, cancers, metabolic and neurodegenerative disorders. The literature review discusses the biological role of the canonical Wnt-SP in the development of the skeleton and in the remodeling of bone tissue. The Wnt signal transmission changes observed during genetic mutations cause various human skeletal diseases. Understanding the functional mechanism involved in the development of bone abnormality could open new horizons in the treatment of osteoporosis, by affecting the Wnt-SP. The design of antibodies to sclerostin, a Wnt-SP inhibitor, is most promising now. The paper summarizes the studies that have investigated the canonical Wnt-SP and designed drugs to treat osteoporosis.

The article describes two clinical cases of severe primary hyperparathyroidism (PHPT) caused by parathyroid carcinoma in young female patients who underwent molecular genetic testing to rule out the hereditary forms of PHPT. In both patients, heterozygous germline nonsense mutations of tumor suppressor gene CDC73 encoding parafibromin (p.R91X and p.Q166X) were identified using next-generation sequencing with Ion Torrent Personal Genome Machine (Thermo Fisher Scientific — Life Technologies, USA). It is the first description of CDC73 mutations in Russia, one of the mutations is described for the first time in the world. Identification of germline mutations in the CDC73 gene in patients with PHPT necessitates regular lifelong screening for other manifestations of hyperparathyroidism-jaw tumor syndrome (HPT-JT), PHPT recurrence due to parathyroid carcinoma as well, and identification of mutation carriers among first-degree relatives.

Microribonucleic acids (miRNAs) are a class of noncoding RNAs that regulate posttranscriptional gene expression. These molecules are regulators of cell proliferation, metabolism, apoptosis, and differentiation. MiRNAs are not degraded by RNAases and their concentrations can be measured in different body fluids, including serum. The expression of miRNAs varies in intact tissues and tumors, including pituitary adenomas. Pituitary tumors are encountered in 22.5% of the population and, in a number of cases, may be asymptomatic, but in case of invasion or/and hormone overproduction, their clinical presentation is severe with multiple symptoms leading to disability and even death. The mechanisms for the development and progression of pituitary tumors and the markers for remission and recurrence have not been adequately investigated. This literature review discusses the biological significance of miRNAs in pituitary tumors and the potential value of circulating miRNAs as biomarkers.

The article briefly reviews the specific features of target-organ lesions in multiple endocrine neoplasia type 1 (MEN1) syndrome and a clinical case of genetically confirmed MEN1 syndrome in a young female patient. Despite the relative rarity of this disease, timely diagnosis, treatment and screening for its main components are very important for the overall prognosis of patients with MEN1 and their first-degree relatives who are MEN1 gene mutation carriers. The described case is noteworthy for a number of specific features. The authors could find no account of optic chiasm glioma within the framework of MEN1 in the literature. Moreover, therapy-resistant somatoprolactinoma engages attention, which points to its aggressive nature with pituitary adenoma that is not been clearly visualized on magnetic resonance imaging. Of interest is the order of detection of neoplasms, in particular the manifestation of hypoglycemic episodes as a sign of organic hyperinsulinism, which have been initially regarded as epileptic seizures, after the use of sustained-release somatostatin analogues for the treatment of acromegaly.

Aim. To investigate efficacy, tolerance and safety of the drug vitrum osteomag one tablet of which contains 600 mg calcium (1500 mg calcium carbonate), 200IU of cholecalcepherol, 40 mg of magnesium, zinc (7.5 mg), copper (1 mg), manganese (1.8 mg) and boron (250 meg) in women with osteopenia for prevention of osteoporosis Material and methods. Л multicenter comparative open trial ofvitrum osteomag influence on mineral bone density (MED), change of pain syndrome in bones, index of calcium-phosphorous metabolism covered 334 postmenopausal women with osteopenia. MBD was measured in low-back spine and proximal part of the hip with DEXA method. All the patients were divided into 3 groups: 125 women taking 2 tablets ofvitrum osteomag daily for 12 months (group 1); 111 women taking 1500 mg calcium carbonate (group 2); 96 women - control group (only observation). Results. Vitrum osteomag relieved pain in the back and joints, had a positive effect on bone density (+1.5%) and proximal parts of the hip (0.6-0.93%) exceeding the effect of calcium carbonate only which preserves the initial MBD in low back spine but does not prevent bone loss in the hip. MBD dynamics in patients given vitrum osteomag differs essentially from one in the control group (from -1.9 to -2.91%) which demonstrates a reliable preventive anti-osteoporotic effect of this medication. The drug increases the level of general and ionized calcium in blood but does not cause hypercalcemia lowering the level of parathormone in blood. The rate of side effects in group 1 was 14,4% and did not differ much from that in group 2 (16.2%). Conclusion. The results of the study allow to recommend vitrum osteomag for prophylaxis of a rapid loss of bone tissue mineral density.