Semaglutide 6-months therapy of type 2 diabetes mellitus restores adipose progenitors potential to develop metabolically active adipocytes.

BACKGROUND: Nowadays type 2 diabetes mellitus (T2DM) leads to population mortality growth. Today glucagon-like peptide type 1 receptor agonists (GLP-1 RA) are one of the most promising glucose-lowered drugs with anorexigenic and cardioprotective effects. The present study aims to determine the effects of GLP-1 RA semaglutide 6-month therapy on T2DM patient metabolic parameters and adipose progenitor cell health. METHODS: T2DM patients (N = 8) underwent clinical characterization and subcutaneous fat biopsy at start point and after semaglutide 6-month therapy. Adipose-derived stem cells (ADSC) were isolated by enzymatic method. Cell proliferation analysis was performed by MTT and immunocytochemistry. White and beige adipogenesis was analyzed by BODIPY493/503 staining and confocal microscopy. Adipocyte's metabolic properties were estimated by 3H- and 14C-based metabolic assays. Thermogenesis analysis was performed by ERthermAC staining and confocal microscopy. Protein markers were assessed by Western blotting. RESULTS: Semaglutide 6-month therapy demonstrated significant anorexigenic and glucose-lowering effects. However, insulin sensitivity (HOMA-IR and M-index) was unchanged after therapy. Semaglutide 6-month therapy increased ADSC proliferation and white and beige adipogenesis. Moreover, lipid droplets fragmentation was observed in beige adipocytes. Both white and beige adipocytes after semaglutide therapy demonstrated 2-3 fold growth of glucose uptake without changes in insulin sensitivity. Newly formed white adipocytes demonstrated glucose utilization for active ATP synthesis, whereas beige adipocytes for canonical thermogenesis. CONCLUSIONS: Our study has revealed that semaglutide 6-month therapy has not only systemic anorexigenic effects, but can markedly improve adipose tissue health. We have demonstrated critical restoration of ADSC renewal functions, which potentially can be involved in semaglutide based weight loss.

[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.

[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.

[BRCA1 and Estrogen Receptor α Expression Regulation in Breast Cancer Cells].

BRCA1 (breast cancer 1) protein is involved in the genome stability maintenance participating in homologous recombination-dependent DNA repair. Disruption of BRCA1 functioning is associated with breast and ovarian cancer. Despite the important role of BRCA1 in DNA repair in all cell types, the development of BRCA1-associated cancer takes place mainly in estrogen-dependent tissues such as breast and ovarian ones. Using breast cancer cell line MCF-7 it was demonstrated in in vitro experiments that the estrogen 17ß-estradiol (E2), phytoestrogens (genistein and apigenin) and antiestrogens (tamoxifen and fulvestrant) inhibited estrogen receptor (ERα) expression while only genistein influenced BRCA1 increasing its expression. In hypoxia, that is an important factor of solid tumors progression, the decrease of BRCA1 and ERα expression was demonstrated in MCF-7 cells. Therefore, hypoxia influences both BRCA1-dependent DNA repair and hormonal regulation of breast cancer cell growth. Taken together, obtained results demonstrate a relationship between BRCA1 and steroid hormones signal transduction pathways in breast cancer cells and point out to the importance of complex BRCA1 and ERa expression regulation mechanisms studies including epigenetic gene expression regulation.

[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.

[Streptozocin-induced Alzheimer's disease as an independent risk factor for the development of hyperglycemia in Wistar rats].

BACKGROUND: In recent years the theme of the relationship of Alzheimers disease (AD) and metabolic disorders has been widely discussed. Nevertheless, it remains unclear whether AD is a direct cause of carbohydrate metabolism disorders or it is the presence of classical risk factors for type 2 diabetes mellitus (DM 2), primarily obesity, that significantly increases the risk of AD. AIM: To evaluate the separate contribution of two factors to the development of disorders of carbohydrate metabolism: (1) weight gain due to a high-calorie diet and (2) experimental-induced AD. METHODS: Male Wistar rats were injected with streptozocin (STZ) in the lateral ventricles of the brain to induce AD or saline (sham operated animals - SO) during stereotactic operations. After 2 weeks, the animals were divided into four groups: 1) the SO group, which was assigned to the normal calorie (NCD) diet (SO NCD); 2) the SO group, which was assigned to the high-calorie diet (SO HCD); 3) the group to which the norm-calorie diet was prescribed after the administration of STZ into the lateral ventricles of the brain (STZ NCD); 4) the group to which the HCD was assigned after the administration of STZ (STZ HCD). The animals were on a diet for 3 months. Intraperitoneal glucose tolerance tests were carried out before the diet and after 3 months. At the end of the study, a morphological assessment of brain tissue, pancreas, and liver was performed. RESULTS: 3 months after surgical interventions and the appointment of diets, the glycemic curves significantly differed in the 4 studied groups: normoglycemia persisted only in the SO + NCD group, while HCD and the STZ administration were accompanied by the development of hyperglycemia (p = 0.0001). The STZ + NСD group, which represented the isolated effect of AD, was also characterized by impaired carbohydrate metabolism. A morphological study showed that HCD leads to a more pronounced ectopic accumulation of fat in the liver and pancreas tissue than NCD. The administration of STZ, regardless of the diet, led to changes typical for the AD model an increase in the size of the ventricles of the brain, degeneration of white matter, and the accumulation of -amyloid in the hypothalamus. CONCLUSIONS: The STZ-induced brain damage typical for AD led to impaired carbohydrate metabolism regardless of diet and was an independent risk factor for hyperglycemia.

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.

[Identification of proteins associated with transcription factors HOXA9 and E2A-PBX1 by tandem affinity purification].

Chimeric transcription factor E2A-PBX1 induces the development of acute lymphoblastic B-cell leukemia in children. Using a transgenic mouse model, we previously demonstrated that homeobox (HOX) gene HOXA9 genetically interact with E2A-PBX1 gene in the development of B-cell leukemia in mice. HOXA9 itself is a potent oncogene resulting in myeloid leukemia when overexpressed, which is strongly accelerated by its collaborator Meis1. HOX, PBX1 and MEIS1 proteins have been shown to form hetero dimeric or trimeric complexes in different combinations. Cooperative interaction between PBX1 and HOX proteins enhances their DNA binding specificity, essential for HOX dependent developmental programs. PBX1 is retained in E2A-PBX1, and thus the strong transcriptional activator properties of E2A-PBX1 may lead to aberrant activation of normally repressed targets of HOX-PBX complexes. However, although there is evidence that E2A-PBX1 could bind to HOX and MEIS1 proteins it is still unclear whether such complexes are actually required for leukemic transformation or whether E2A-PBX1 and HOXA9 are each part of larger protein complexes acting in independent complementing oncogenic pathways. In this study we aim to search for other HOXA9 and E2A-PBX1 interacting proteins. To identify novel proteins interacting with human E2A-PBX1 or HOXA9 we used tandem affinity purification (TAP) of protein complexes from 697 pre-B leukemic and HeLa cell lines transduced to express E2A-PBX1 or HOXA9, respectively, with covalently attached FLAG/HA peptides. The protein composition of each complex was determined using tandem mass-spectrometry. In the E2A-PBX1 containing complex we identified lymphoid transcription factor IKAROS, chromatin remodeling factors of SWI/SNF family while multiple subunits of translation initiation factor eIF3, E3 ubiquitin ligase UBR5 emerged from the HOXA9 complex as potential critical protein partners. This is the first time the protein partners of either E2A-PBX1 or HOXA9 oncoproteins were identified using an unbiased biochemical approach. The identification of translation initiation factors associated with HOXA9 might indicate a novel function for HOX proteins independent of their transcriptional activity.

[Mass spectrometry analysis of blood plasma lipidome as method of disease diagnostics, evuation of effectiveness and optimization of drug therapy].

A new method for the analysis of blood lipid based on direct mass spectrometry of lipophilic low molecular weight fraction of blood plasma has been considered. Such technique allows quantification of hundreds of various types of lipids and this changes existing concepts on diagnostics of lipid disorders and related diseases. The versatility and quickness of the method significantly simplify its wide use. This method is applicable for diagnostics of atherosclerosis, diabetes, cancer and other diseases. Detalization of plasma lipid composition at the molecular level by means of mass spectrometry allows to assess the effectiveness of therapy and to optimize the drug treatment of cardiovascular diseases by phospholipid preparations.

[Secretion of incretin hormones in people having risk factors for type 2 diabetes mellitus].

AIM: To study the secretion of glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP),and glucagon- like peptide 2 (GLP-2) in response to a carbohydrate load in people with risk factors for type 2 diabetes mellitus (DM2) in relation to the type of carbohydrate metabolic disturbances and age. SUBJECTS AND METHODS: One hundred and twenty-seven patients having DM2 risk factors who had not previously received glucose- lowering therapy underwent an oral glucose tolerance test (OGTT). The plasma levels of glucose, insulin, glucagon, GLP-1, GIP, and GLP-2 were determined at 0, 30, and 120 minutes of the test. RESULTS: According to the findings, the patients were divided into 3 groups: 1) normal glucose tolerance; 2) prediabetic states (impaired glucose tolerance and/or impaired fasting glycemia); 3) new-onset DM2. OGTT showed that the secretion of GLP-1 was lower and that of GIP and GLP-2 was higher in patients with DM2. GLP-1 secretion decreased with patient age. CONCLUSION: During OGTT, there is a statistically significantly difference in the secretion of incretin hormones in persons with varying degrees of carbohydrate metabolic disturbances: the peak GLP-1 secretion is the highest in healthy individuals and lowest in the patients with DM2; on the contrary, the peak GLP2 and GIP secretions are the highest in the patients with DM2. This may suggest that GLP-1 and the two other hormones (GLP-2 and GIP) show opposite effect in the regulatory mechanisms of carbohydrate metabolism. GLP-1 secretion is decreased with age, which may be one of the reasons for the higher prevalence of DM2 among the elderly.

Association of the interferon-ß gene with pericentromeric heterochromatin is dynamically regulated during virus infection through a YY1-dependent mechanism.

Nuclear architecture as well as gene nuclear positioning can modulate gene expression. In this work, we have analyzed the nuclear position of the interferon-ß (IFN-ß) locus, responsible for the establishment of the innate antiviral response, with respect to pericentromeric heterochromatin (PCH) in correlation with virus-induced IFN-ß gene expression. Experiments were carried out in two different cell types either non-infected (NI) or during the time course of three different viral infections. In NI cells, we showed a monoallelic IFN-ß promoter association with PCH that strongly decreased after viral infection. Dissociation of the IFN-ß locus away from these repressive regions preceded strong promoter transcriptional activation and was reversible within 12 h after infection. No dissociation was observed after infection with a virus that abnormally maintained the IFN-ß gene in a repressed state. Dissociation induced after virus infection specifically targeted the IFN-ß locus without affecting the general structure and nuclear distribution of PCH clusters. Using cell lines stably transfected with wild-type or mutated IFN-ß promoters, we identified the proximal region of the IFN-ß promoter containing YY1 DNA-binding sites as the region regulating IFN-ß promoter association with PCH before as well as during virus infection.

[Antistroke activity of Actoinvit (substance S-1) in experimental hemorrhagic stroke].

A model of hemorrhagic stroke (HS) (intracerebral posttraumatic hematoma) has been used to show that oral Actoinvit (substance S-1) in a daily dose of 500 mg/kg for 7 days causes a steady-state antistroke effect. At the same time the major neurological parameters became lower and the total indices of orientative-trying behavior improved 24 hours just after administration of the drug. Muscle tone, coordination of movements, and memory impairment recovered on days 7-14 after the simulation of HS. The course use of the agent prevented death from HS in 80% of the animals.

[Morphologic changes in the thyroid of rats after a single and fractional gamma-irradiation].

Asynchronous reactions of the thyroid morphological parameters to ionizing radiation were observed in male rats after 24 hours following single and fractional exposure. In delayed periods the thyroid function was suppressed no matter the dose of single and fractional irradiation.

How is epigenetic information on chromatin inherited after DNA replication?

Although most somatic cells have identical genetic information, gene expression profiles are quite distinct in each cell type. The gene expression profiles are considered to be determined mainly by chromatin-encoded epigenetic information that includes histone modifications, histone variants, and factors such as HP1 and polycomb group proteins that organize higher-ordered chromatin structures. To gain insights into how such epigenetic information on chromatin is inherited on daughter DNA strands after DNA replication, we have purified the preassembled form of histone H3 by immunoaffinity purification. The histone H3 complex contains the two histone H3-H4 chaperones CAF1 and ASF1. Surprisingly, the H3 complex also contains a pair of H3-H4 dimers. This observation is striking because histones H3-H4 are known to exist as tetramers in solution. Since histones H3-H4 in the predeposition complex exist as a dimer, this raises the possibility that the H3-H4 dimer in the complex pairs with a parental H3-H4 dimer, assembling the de novo-synthesized and parental H3-H4 dimers in the same nucleosome. Based on these results, we propose a semi-conservative model of nucleosome duplication, which allows for segregation of parental H3-H4 dimers with encoded epigenetic information evenly to daughter DNA strands.

Effects of substance S-1 on energy metabolism and cAMP concentration in rat tissues during physical stress.

Substance S-1 increased energetic potential of skeletal muscles and increased cAMP level in the brain, heart, and liver of male Wistar rats at rest and after forced swimming.

[Selenium: the biological role and antioxidant activity]. / Selen: biologicheskaia rol' i antioksidantnaia aktivnost'.

Selenium is essential trace element, sulphur analogue with high chemical activity, component of some selenoproteins and enzymes: glutathione peroxidase and other peroxidases, blood and tissue proteins. As to their biological action mechanism selenium and its compounds are antioxidants. Selenium is active immunomodulator, much more potent anti-oxidant than vitamins E, C and A, beta-carotene, but much more toxic. It takes part in thyroxine conversion to triiodethyronine in thyroid hormone biosynthesis. As sperm antioxidant selenium protected its motility and fertility. Selenium is a serious factor of biological and antioxidant protection of vascular endothelium, of low-density lipoproteins, protection of DNA, chromosomes. As food component selenium is an exceptional agent of protection from atherosclerosis, coronary ischemic disease and cancer. Some hydrobionts, liver, kidney, meal, corn and garlic, onion, cabbage, broccoli are dietary products with high content of selenium.

Effects of substance S-1 on rats with impaired hearing.

Intraperitoneal administration of substance S-1 to male Wistar rats with impaired hearing markedly increased hearing acuity. Substance S-1 had no negative effects on hearing in intact animals.

The physiological significance of beta -actin mRNA localization in determining cell polarity and directional motility.

beta-actin mRNA is localized near the leading edge in several cell types, where actin polymerization is actively promoting forward protrusion. The localization of the beta-actin mRNA near the leading edge is facilitated by a short sequence in the 3' untranslated region, the "zip code." Localization of the mRNA at this region is important physiologically. Treatment of chicken embryo fibroblasts with antisense oligonucleotides complementary to the localization sequence (zip code) in the 3' untranslated region leads to delocalization of beta-actin mRNA, alteration of cell phenotype, and a decrease in cell motility. To determine the components of this process responsible for the change in cell behavior after beta-actin mRNA delocalization, the Dynamic Image Analysis System was used to quantify movement of cells in the presence of sense and antisense oligonucleotides to the zip code. It was found that net path length and average speed of antisense-treated cells were significantly lower than in sense-treated cells. Total path length and the velocity of protrusion of antisense-treated cells were not affected compared with those of control cells. These results suggest that a decrease in persistence of direction of movement and not in velocity results from treatment of cells with zip code-directed antisense oligonucleotides. To test this, direct analysis of directionality was performed on antisense-treated cells and showed a decrease in directionality (net path/total path) and persistence of movement. Less directional movement of antisense-treated cells correlated with a unpolarized and discontinuous distribution of free barbed ends of actin filaments and of beta-actin protein. These results indicate that delocalization of beta-actin mRNA results in delocalization of nucleation sites and beta-actin protein from the leading edge followed by loss of cell polarity and directional movement.