Obesity and obesity-related disorders, such as type 2 diabetes, has become a global epidemic. Although there is abundant
evidence that diet and exercise are key factors in the obesity epidemic, it is equally clear that a variety of environmental factors play an
important role in this process. These include such factors as gut flora, insufficient sleep, stress, social environment, maternal influences,
endocrine disrupters and others. These factors target key hormonal signaling pathways involved in adipogenesis, regulation of appetite.
They are also likely to play important roles in obesity epidemic and are therefore worthy of further study.

The review presents data confirming that fat tissue is a significant source of synthesis of all components of renin-angiotensin
system (RAS). It is proposed that activation of fat tissue RAS components have a local paracrine and autocrine actions on adipocytes,
regulates their growth and differentiation, induces subclinical inflammation and insulin resistance (IR). Thus, hyperactivity of local
RAS in fat tissue is one of the mechanisms of visceral obesity, IR and metabolic syndrome. Use of traditional RAS blocking medications
(angiotensin converting enzyme inhibitors, angiotensin receptor blockers) is followed by IR decrease and prevents from development of
type 2 diabetes mellitus. The perspectives of use of a new RAS blocker from a group of direct rennin inhibitors - aliskiren - for correction
of metabolic abnormalities in visceral obesity are considered.

Octreotide is a synthetic analog of hypothalamic hormone somatostatin. This neuropeptide is widely distributed in humans and animals in central nervous system and periphery, which defines its potential regulatory functions. In 1987 the first registration was received for octreotide preparation, Sandostatin, for treatment of acromegaly and carcinoid tumors. In 1997 a long lasting form of octreotide appeared - Sandostatin LAR. At the present time both preparations have found their use in multiple areas of medicine for treatment of different metabolic, neuroendocrine and oncologic diseases.

In recent decades, overweight and obesity have become a major problem for most countries. According to the World Health
Organization (WHO), more than a billion people worldwide are overweight and more than 300 million are obese. These clinical and
experimental studies highlight a clear relationship between obesity and several chronic diseases such as type 2 diabetes mellitus (T2DM),
atherosclerosis, coronary heart disease, high risk of oncological diseases, disorders of the reproductive sphere, pathology of the musculoskeletal
system, as well as deviations in mental status and processes of social adaptation. Therefore, considerable efforts of modern endocrinology
focused on the study of etiopathogenetic aspects that underlie these diseases and identification of possible markers.

Diabetes mellitus is associated with increased risk of several types of cancer, and also with increased cancer mortality. Chronic
hyperinsulinemia plays the main pathogenetic role in this association, which is mediated by a number of molecular mechanisms, described
in this issue. Drugs that increase insulin sensitivity and reduce hyperinsulinemia (metformin in the first place) display anticancer
effect. Aside from the anticancer effect, mediated by reduction of insulin resistance, metformin may directly suppress cancer cells
growth and proliferation via stimulation of AMP kinase (AMPK). Antiproliferative action of metformin in breast and ovarian cancer is
confirmed in a number of experimental and clinical trials. Its found out that therapeutic effect of metformin in treatment of breast cancer
depends on the presence/absence of some molecular features of the tumor (for example, increased expression of HER2 and/or activation
of p70S6K1). In order to specify mechanisms of action and effects of metformin in oncological practice several trials are being conducted
or planned, most of all, in all subtypes of breast cancer. Confirmation of the anticancer effectiveness of metformin will promote an expansion
of its use in clinical practice and in clinical oncology, particularly.

Obesity is an unsolved problem of modern society, furthermore it is one of the main risk factors for type 2 diabetes mellitus, cardiovascular
diseases and cancer, pathology of musculoskeletal and digestive systems, reproductive disfunction both for women and for men.
It is known that treatment any chronic disease is rather complicated, not only for doctors but also for the patient, because it requires from
the patient a careful self-control and substantial changes in lifestyle. In modern clinical practice, various methods of treatment of obesity are
used: diet therapy, exercise therapy, physiotherapy, pharmacotherapy, psychotherapy and surgery. Modern methods of treatments of obesity
are reviewed in this article

The article describes evidence-based approaches to treatment of morbid obesity, including surgical interventions designated for
bodyweight reduction and provides comparative analysis of efficacy and safety of lifestyle interventions, medical treatment and various
types of bariatric surgery. Detailed description of diagnosis, treatment and prevention of post-surgical vitamin and mineral deficiencies
is given. Special attention is paid to high prevalence of mental disorders in patients with morbid obesity, their role in its development,
their influence on outcomes of surgical intervention and potential patient dissatisfaction with its results. Necessity of thorough selection
of patients for bariatric surgery is emphasized, with assessment of their mental state and proper organization of subsequent life-long
follow-up after operation