[Obesity and diabetes - are they always together?]

Obesity and type 2 diabetes mellitus (DM 2) are two interrelated metabolic diseases widespread throughout the developed world. However, up to 30% of individuals with a long history of obesity do not have a carbohydrate metabolism disorder. This article presents the results of a multi-year study of adipose tissue biology in obese individuals with DM 2 compared with individuals with the same history of obesity without DM 2. Comparative analysis of hormonal, cellular, and genetic factors in two groups of patients showed that DM 2 occurs in individuals with abnormal proliferation and adipogenic differentiation of mesenchymal stem cells (MSCs) of adipose tissue. It leads to adipocyte hypertrophy and inflammatory infiltration of adipose tissue macrophages, resulting in increased insulin resistance and diabetogenic effects. These disorders are due to abnormal expression of genes responsible for the proliferation and adipogenic differentiation of MSCs. The study of the possible reversibility of abnormal changes in adipose tissue MSCs in obese patients after significant weight loss and DM 2 remission appears to be a promising research direction. The ability to control adipose tissue progenitor cells may represent a new target for treating and preventing metabolic disorders in obesity.

[The role of glucose and insulin in the metabolic regulation of growth hormone secretion].

The exact physiological basis for the suppression of growth hormone secretion by oral glucose intake remains unknown, despite the widespread use of the oral glucose tolerance test in endocrinology. Lack of growth hormone suppression by glucose occurs in about a third of patients with acromegaly, as well as in other disorders. It is currently known that the secretion of growth hormone is affected by various factors, such as age, gender, body mass index, and the redistribution of adipose tissue. There is also evidence of the impact of overeating as well as being overweight on the secretion of growth hormone. It is known that both of these conditions are associated with hyperinsulinemia, which determines the possibility of its predominant role in suppressing the secretion of growth hormone. The purpose of this review is to discuss the accumulated data on the isolated effects of hyperglycemia and hyperinsulinemia on growth hormone secretion, as well as other metabolic regulators and conditions affecting its signaling. Understanding of the pathophysiological basis of these mechanisms is essential for further research of the role of glucose and insulin in the metabolic regulation of growth hormone secretion. However, the studies in animal models are complicated by interspecific differences in the response of growth hormone to glucose loading, and the only possible available model in healthy people may be the hyperinsulinemic euglycemic clamp.

[Prognostic factors for the carbohydrate metabolism normalization in patients with type 2 diabetes mellitus and obesity using liraglutide 3.0 mg per day].

BACKGROUND: Glucagon-like peptide-1 receptor agonists (GLP-1 RA) are innovative drugs that effectively reduce glycemic levels and overweight in patients with type 2 diabetes mellitus (T2DM). However, the criteria for predicting the hypoglycemic effect of this group of drugs have not been practically defined. AIM: To assess the factors contributing to the achievement the glycemia normalization in patients with diabetes mellitus and obesity by adding to antihyperglycemic therapy (AT) a drug from the GLP-1 RA group liraglutide 3.0 mg per day. MATERIALS AND METHODS: A single-center, prospective, non-randomized study was provided. The objects of the study were patients with T2DM and obesity (n=22). Liraglutide 3.0 mg per day was added to the current AT of patients. Initially, the parameters of carbohydrate metabolism, hormones of the incretin system on an empty stomach and during the mixed-meal test, insulin resistance using the euglycemic hyperinsulinemic clamp test, and body composition were studied. After 9 months of therapy, all studies were repeated and a search for possible predictors of the carbohydrate metabolism normalization was made. RESULTS: The body mass index of patients decreased from 42.4 [37.7; 45.0] to 35.9 [33.0; 40.9] kg/m2. Fasting blood glucose and glycated hemoglobin levels decreased from 9.02 [7.40; 11.37] mmol/L and 7.85 [7.43; 8.65]% up to 5.90 [5.12; 6.18] mmol/L and 6.40 [5.90; 6.60]%, respectively. 14 (63.6%) patients reached normoglycemia. Insulin resistance according to the clamp test did not change over the study. Basal concentrations of oxyntomodulin, glycentin and the area under the GLP-1, oxyntomodulin, glycentin curve significantly decreased 9 months after liraglutide administration. The prognostic marker of the achievement of normoglycemia during therapy with liraglutide 3.0 mg/day is the level of endogenous GLP-15.5 pmol/L before the appointment of arGPP-1 therapy. CONCLUSION: The concentration of endogenous GLP-1 before the appointment of liraglutide therapy at a dose of 3.0 mg per day can be used for prediction the drug hypoglycemic effect and achieving normoglycemia possibility.

[Obesity without diabetes: the role of hormonal regulation].

AIM: Obese patients without diabetes present an interesting phenotype to explore protective mechanisms against type 2 diabetes (T2D) development. In our study we looked for specific hormonal features of obese patients without T2D. MATERIALS AND METHODS: We included 6 groups of patients with different metabolic profiles (n=212): controls with BMI25 kg/m2, HbA1c6%, age 30 years; patients with 25BMI30 kg/m2and HbA1c6%; patients with 25BMI30 kg/m2and HbA1c6%; patients with BMI30 kg/m2and HbA1c6% (+ Obesity - T2D) obese patients without T2D or prediabetes; patients with BMI30 kg/m2and newly-diagnosed T2D/prediabetes, HbA1c6%; patients with known history of T2D on glucose-lowering drugs with BMI30 kg/m2. Insulin, GLP-1, GIP were measured during glucose-tolerance test at 0, 30 and 120 minutes; insulin resistance (IR) was assessed by HOMA-IR. RESULTS: Waist circumference was bigger in patients with obesity despite their metabolic profile comparing to patients without obesity (p0.001). Waist-to-hip ratio was similar in patients with different metabolic status. According to IR + Obesity - T2D group had intermediate position: IR was higher in that group comparing to people without obesity, but was less that in patients with obesity and HbA1c6% (p0.001). + Obesity - T2D group had the most potent baseline insulin secretion, assessed by НОМА-%band the highest postprandial secretion, measured by insulinogenic index among all patient groups with obesity (p0.001). There was no significant difference in GLP-1 secretion; GIP secretion was higher in patients with BMI30 kg/m2comparing to people with BMI30 kg/m2(p0.01).

Role of MicroRNAs in the Regulation of Subcutaneous White Adipose Tissue in Individuals With Obesity and Without Type 2 Diabetes.

Obesity is a high-risk factor for such comorbidities as cardiovascular disease, several types of cancer, and type 2 diabetes; however not all individuals with obesity have such complications. Approximately 20% of individuals with obesity are metabolically healthy. This study focused on differences between obese individuals with and without type 2 diabetes (T2D+ and T2D-, respectively) on the transcriptome level. Subjects included were 35 T2D- patients with obesity and 35 T2D+ patients with obesity with the same body mass index (BMI). The study was based on the transcription analysis of mRNA and microRNAs (miRs) by RNAseq. In the first step, we performed RNAseq of miRs, in the second step, we analyzed only those mRNA, which appeared targets for significant miRs from the first step. All RNAseq results were validated by qPCR. There were seven miRs differently expressed with adjusted p-value <0.1, which were confirmed by qPCR. Five among them: miR-204-5p, miR125b-5p, miR-125a-5p, miR320a, miR-99b-were upregulated in T2D+ patients with obesity, while only two miRs, miR-23b-3p, and miR197-3p, were increased in T2D- patients with obesity. These seven miRs target two groups of genes: matrix metalloproteinases and TGFß signal pathway genes. According to the results of transcriptome analysis, the main difference between T2D+ and T2D- patients with obesity was in adipogenesis and fibrosis regulation by matrix metalloproteinases and SMAD4-RUNX2 signal cascade. Based on the data about transcription profiles of both groups, we suggested that the process of fibrosis in T2D+ patients with obesity is more pronounced than in T2D- patients with obesity.

[Glycemia normalization in patients with obesity and type 2 diabetes mellitus: bariatric surgery vs pharmacological therapy].

AIMS: To compare glucose - lowering and weight reduction capacity of bypass operations (gastric bypass (GB), biliopancreatic diversion (BPD) vs GLP-1 agonist liraglutide 3.0 mg (models of maximum incretin effect) for 6 months. MATERIALS AND METHODS: 46 patients with type 2 diabetes and long history (≥10 years) of obesity were divided into 2 groups: surgery - group (n=23) and liraglutide - group (n=23), where liraglutide 3.0 mg in dose - escalation manner was added to baseline glucose - lowering therapy. Anthropometric parameters, HbA1c and insulin resistance (IR) by hyperinsulinemic euglycemic clamp (M-value) were measured before and 16 weeks after the intervention. With the stabilization of glycemia (≤6.5 mmol/l at fasting state, ≤8 mmol/l postprandial) the initial glucose - lowering therapy was canceled. RESULTS AND DISCUSSION: Both surgery and liraglutide 3.0 mg provided target HbA1c in 16 weeks. Bypass operations led to elimination of glucose - lowering therapy in 82.6% patients due to a more significant weight reduction and decrease in IR. In liraglutide - group previous glucose - lowering therapy was cancelled in 78.3% patients, mainly receiving baseline mono - and two - component therapy. The most significant difference between interventions was achieved in BMI (-8.9 kg in surgery group vs -3.8 kg in liraglutide group, p.

Low proliferative potential of adipose-derived stromal cells associates with hypertrophy and inflammation in subcutaneous and omental adipose tissue of patients with type 2 diabetes mellitus.

BACKGROUND: Obesity and type 2 diabetes mellitus (T2DM) are among the most important morbidity factors. In this study we tested the hypothesis that low proliferative potential of adipose derived stromal cells (ADSC) associates with reduced formation of new fat depots, excess accumulation of fat in the functional adipocytes and their hypertrophy, resulting in fat inflammation and insulin resistance. METHODS: We screened two groups of obese patients with or without T2DM, matched for BMI, age, and duration of obesity to test the hypothesis that hypertrophy and decreased renewal of adipocytes may underlie transition from obesity to T2DM. All patients were matched for carbohydrate metabolism (fasting blood glucose level, glycated hemoglobin, HOMA-IR index and M-index). The subcutaneous and omental fat tissue biopsies were obtained during bariatric surgery from obese individuals with or without T2DM. The morphology and immunophenotype of subcutaneous and omental fat was assessed in frozen tissue sections. ADSC were isolated from both types of fat tissue biopsies and screened for morphology, proliferative potential and inflammatory status. RESULTS: The non-diabetic patients had normal carbohydrate metabolism and moderate insulin resistance measured by HOMA-IR and hyperinsulinemic clamp (M-index), while T2DM patients were extremely insulin resistant by both indexes. The average size of diabetic adipocytes was higher than that of non-diabetic in both subcutaneous and omental fat tissues, indicating adipocyte hypertrophy in T2DM. Both these tissues contained higher level of macrophage infiltration and increased M1-like to M2-like ratio of macrophage subpopulations, suggesting increased fat inflammation in T2DM. This was confirmed by increased activatory phosphorylation of stress-induced JNK1/2 in diabetic ADSC. CONCLUSION: These results suggest that blunted proliferation and increased hypertrophy of diabetic ADSC may lead to reduced insulin sensitivity via increased inflammation mediated by M1 macrophages and JNK1/2 pathway.

[Is it possible to achieve sustained remission or cure of type 2 diabetes mellitus in the 21st century?] / Vozmozhna li dlitel'naia remissiia ili izlechenie sakharnogo diabeta 2-go tipa v XXI veke?

A practitioner has a wide range of the hypoglycemic drugs for type 2 diabetes mellitus (T2DM) treatment, which can be used within a normal or near-normal range for long-term glycemic control. However, the question remains whether there are ways to achieve not only satisfactory glycemic control, but also T2DM remission (or even complete cure). The review presents an update on the concept of T2DM remission and describes the ways of its possible achievement with non-drug and drug treatments and surgery. The mechanisms of T2DM remission are given.