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Objective: To study the histological changes in lung of rats, evaluate their dynamics and determine the Bax and Bcl-2 genes expression in bronchial epithelium, alveolar type 1 cells and neutrophils at different times after the administration of baclofen., Material and Methods: The experiment was conducted on 20 mature (at the age of 20 weeks) male Wistar rats with a mass of 290-350 g, distributed in 4 groups (5 rats in each). Animals in the control group did not receive baclofen. Rats in experimental groups received baclofen at a dose of 85 mg/kg: in the 1st group, the experiment duration was 3 hours (time to maximum observed blood drug concentration); in the 2nd group - 4.5 h (drug half-life and time to maximum observed concentration of the main drug's metabolite - beta-[p-chlorophenyl])-gamma-hydroxybutyric acid in the blood); in the 3rd group - 24 h., Results: A complex of pathological reactions developed in lungs of experimental animals when baclofen muscle relaxant was administered, namely circulatory disturbances at all levels of the microvasculature (venular and capillary congestion, hemorrhages in the interalveolar septums, alveoli, sludge), emphysema, sites of which punctuated with atelectases and dystelectases. The complex of pathological changes in the lungs had a certain dynamics and reached its highest severity by the 24th hour. Bax expression was strong, while Bcl-2 expression was moderate in the immunohistochemical (IHC) study of bronchical epithelium and alveolar type 1 cells, Bax and Bcl-2 expression in neutrophils was moderate in rats of the 1st group. The expression of Bax and Bcl-2 was strong in the bronchial epithelium and alveolar type 1 cells, the expression of Bax in neutrophils was moderate, and BCL-2 - strong in animals of the 2nd group. The expression of Bax in bronchial epithelium and alveolar type 1 cells was moderate, expression of Bcl-2 in bronchial epithelium and alveolar type 1 cells - strong, expression of Bax in neutrophils - weak and expression of Bcl-2 - strong among the rats of the 3rd group., Conclusion: The complex of pathological changes in lungs had a certain dynamic. Data on the histological changes in lungs in combination with the results of the chemical study, can be used to diagnose the poisoning by baclofen and to establish the time since the drug was administered. The results obtained during the IHC study suggest the involvement of apoptosis in the development of lesion of bronchial epithelium and alveolar type 1 cells. In addition, the expression of Bcl-2 in epithelial cells may play a role in the process of their regeneration.

Melatonin (N-acetyl-5-methoxytryptamine, MEL) is a hormone synthesized by the pineal gland. Due to its oncostatic effect, it can be considered as an antitumor agent and used for combination therapy. ABT-737, a Bcl-2 inhibitor, promotes cell death after treatment with agents that induce pro-apoptotic signals. In the present study, the combined effect of MEL and ABT-737 on changes in proliferative and mitotic activity, mitochondrial membrane potential, intracellular production of reactive oxygen species (ROS), and cytosolic Ca^(2+) was studied. Moreover, changes in the expression of anti- and pro-apoptotic proteins (Bcl-2 and Bax), autophagy markers (LC3A/B (I, II)), endoplasmic reticulum stress markers (chaperones BIP and PDI, CHOP) were studied under these conditions. The effect of MEL together with ABT-737 led to an increase in the level of cytosolic Ca^(2+), intracellular production of ROS and a decrease in the membrane potential of mitochondria. The content of Bcl-2 increased, while the level of Bax decreased. Activation of CHOP stimulated autophagy and led to a decrease in the synthesis of chaperones BIP and PDI. It is assumed that melatonin can enhance the effect of other chemotherapeutic agents and can be used in the treatment of tumors.

Obesity is a major disease that causes significant complications. Inhibition of preadipocyte proliferation has the potential to prevent obesity and metabolic diseases. Melatonin is a pineal gland hormone that has various effects on cells and tissues. In this research, we investigated whether melatonin induces apoptosis in 3T3-L1 preadipocytes. 3T3-L1 preadipocytes were cultured until confluence and then treated with 0, 10, 100, and 1000 μM melatonin for 1, 3, and 5 days. A cell viability assay kit was used for determining cell viability. Cell death marker proteins were assessed by Western blot analysis using GAPDH for control. Apoptotic morphological changes with nuclei fragmentation were observed using DAPI staining. Melatonin treatment decreased the phosphorylated extracellular signal-regulated kinases (p-ERK) activation while increasing the activation of caspase-3, 8, and 9. Furthermore, melatonin not only increased Bcl-2-associated X protein (Bax) but decreased B-cell lymphoma 2 (Bcl-2) expression as dose increases from 0 to 1000 μM. The melatonin treatment also suppressed the growth of preadipocytes with increasing concentration. These effects were attenuated by luzindole, a melatonin receptor antagonist and U0126, an inhibitor of p-ERK activation. In conclusion, melatonin can induce apoptosis of 3T3-L1 preadipocytes via p-ERK decrease.

MicroRNA-218 (miR-218) is a short, noncoding RNA, with multiple biological functions. In this study, we aimed to investigate the potential effects of miR-218 on the apoptosis of human ovarian carcinoma cells and the underlying mechanisms by which miR-218 exerted its actions. After over-expressing miR-218 in human ovarian carcinoma (OVCAR3) cells, cell viability was determined by MTT method, cell apoptosis was observed by flow cytometry (FCM), mRNA expression of miR-218, Bcl2, Bax was measured by RT-PCR and protein expression levels of Wnt, tankyrase and β-catenin were quantified by Western blots. Over-expression of miR-218 potently suppressed cell viability and promoted the apoptosis of human ovarian carcinoma cells in a time-dependent manner. In addition, the down-regulation of tankyrase expression level was detected in miR-218-over-expressed cells. Following the block of the Wnt/β-catenin signaling pathway using the inhibitor XAV-939, the effects of miR-218 on the proliferation and apoptosis of human ovarian carcinoma cells were significantly suppressed. Augmenting expression of miR-218 and/or miRNA-218 mimicking therapeutics may provide viable avenue for the treatment of ovarian cancer.

Cancer, along with cardiovascular disorders, is one of the most important problems of healthcare. Pathologies of the hematopoietic system are the most prevalent in patients under 30 years of age, including acute myeloid leukemia (AML), which is widespread and difficult to treat. The review considers the mechanisms that play a significant role in AML cell malignant transformation and shows the contributions of certain genes to both remission and resistance of AML cells to various treatments.

Among the wide array of human neoplasms, primary tumors of bone are relatively uncommon and sundry group of solid tumors traditionally categorized according to their presumed mesenchymal differentiation. A locally aggressive or malignant group of cartilaginous matrix-producing neoplasms with diverse morphological features and clinical behavior require additional ancillary studies for prompt diagnosis and appropriate surgical treatment. They are histologically, behaviorally and genetically diverse, their pathogenesis is poorly understood Moreover treatment options are limited with surgical resection continuing to provide the only possibility of cure in many cases. However, there has been tremendous progress in the last decade in understanding the molecular pathogenesis of sarcoma, which may ultimately lead to more effective therapy and prognostification for these rare malignancies (1. Atypical cartilaginous tumor/grade1chondrosarcomas behave as locally aggressive lesions, and only metastasize in exceptional cases. Only a small percentage of the IDH1mutations can be identified using the specific IDHIRI32H antibody Histologic grade is the most important predictor of local recurrence and metastasis in chondrosarcoma , commonly patents die from locally recurrent tumor ofpelvis or scull, that is difficult to manage surgically Association between ratio of matrix metalloproteinaise- 1 and tissue inhibitor ofmetalloproteinase- 1, expression of metalloproteinase-1, -2 and-9, Col-IV, Cox-2, Bcl-2, Bax in context with histological and clinical data could play a significant role in determining prognosis in patients with borderline cartilaginous tumors. The mandatory application of multidisciplinary care in management of atypical cartilaginous tumor/grade 1 chondrosarcomas with integration of histologic, molecular, radiographic and clinical data is difficult to overestimate.

The in vitro phosphorylated and non-phosphorylated Hsp27 forms concentrations and Bcl-2 proteins affected by Hsp27 inhibition were studied in Jurkat-line tumor cells and healthy donor mononuclear lymphocytes by Western blotting technique. The Hsp27 inhibition causes the increase of intracellular Bax protein concentration and the decrease of Bcl-2 level leading to an increase of apoptotic changes in Jurkat line cells.

Aim: To determine unbalance in the system of programmed cell death in the cells CD34+ of the bone marrow (BM) and peripheral blood (PB) before and after cytostatic impact in acute leukemia (AL)., Material and Methods: Flow cytoflowmetry estimated expression of Bcl-2, Bax, p53 and ACE in the cells CD34+ of BM and PB from 10 AL (4 AML and 6 ALL) patients. PB and BM samples were studied before polychemotherapy (PCT) and in the course of induction treatment: on day +8, +21 (blood only), +36 - 38. Control group consisted of 4 BM donors., Results: The number of CD34+ cells expressing Bcl-2 in AL patients was 46,5 +/- 9,35 % in BM and 39,4 + 10,8 % in PB, in healthy donors - 9 and 32,8 %, respectively. Bax expression in AL patients' cells CD34+ of BM versus this expression in donors was 3 times higher (36,7 +/- 8,1 and 14,8%, respectively), of PC - 2 times lower (40,7 +/- 6,59 and 75,8%, respectively). Expression of p53 in AL patients was 36,8 +/- 9 % in BM and 26 +/- 7,4 % in PB, in donors - 28,2 and 65 %, respectively. ACE expression on the cells CD34+ in AL patients in early disease was 62 +/- 7,57 % in BM and 48 +/- 8,1 % in PB, in donors - 40 and 85 %, respectively. Moreover, there were significant changes in expression of Bcl-2 in BM and Bax, ACE and p53 in PB in the cells CD34+ in AL patients during and after induction PCT., Conclusion: The above changes evidence for unbalance of pro- and antiapoptosis proteins of regulators in AL patients. PCT changes profile of expression of these proteins, but not to the level of healthy donors.

Immunohistochemical study of p53, VEGF, Flt-1/VEGFR1 Ab-1, EGFR, HER-2/neu, Bax, and Cox-2 expression in osteosarcomas was carried out in 40 patients aged 16-70 years. Expression of p53 was detected in 27.5% tumors, VEGF in 15%, Flt-1/VEGFR1 Ab-1 in 97.5%, EGFR in 52.5%, HER-2/neu in 32.5%, Bax in 77.8%, and Cox-2 in 32.3% tumors. Multifactorial analysis showed that the expression of HER-2/neu (p=0.004), p53 (p=0.01), and Cox-2 (p=0.04) in osteosarcomas significantly correlated with unfavorable prognosis for overall survival, while HER-2/neu (p=0.02) and Cox-2 (p=0.003) with relapse-free survival. Analysis of HER-2/neu, p53, and Cox-2 expression in the primary tumor should be taken into consideration in the treatment of patients with osteosarcoma.

The effects of recombinant IL-2 on apoptosis of lymphocytes of healthy donors were studied in in vitro experiments. It was shown that the inductive and inhibitory effects of IL-2 on apoptotic process depend on the dose of the cytokine and cell microenvironmental conditions. Culturing of lymphocytes with recombinant IL-2 increases the percent of cells with reduced transmembrane potential, reduces the content of intracellular proteins Bcl-2, Bcl-X(L) and и Bax, and increases the level of Bad. The proapoptotic effect of this cytokine is realized with participation of nuclear transcription factor NF-κB and transcription factor P53.

Modeling oxidative stress in vitro with 5mM H2O2 has demonstrated a protective role of nitric oxide on realization of constitutional blood neutrophil cell death. The NO-synthase inductor L-arginine and the inhibitor of nitric oxide synthesis, L-NAME, influenced on the amount of annexin-positive cells, the content of Bax protein, reactive oxygen species, cyclic nucleotides, and calcium homeostasis in neutrophils under conditions realizing programmed death during oxidative stress in vitro and under acute inflammation. During oxidative stress L-arginine normalized the increased intracellular Ca2+ level and the cAMP/cGMP ratio due to increase of cGMP level, stabilized metabolism and prolonged neutrophil life. During acute inflammation NO induction was insufficient for limitation of Ca2+ release into cytosol and for onset of the apoptotic effect; blockade of NO synthesis deteriorated this situation by activating neutrophil apoptosis due to the sharp increase in Ca2+ content and reduction of cyclic nucleotides in cytosol. The protective effect of NO on neutrophil cell death during oxidative dysbalance is not associated with regulation of apoptotic protein Bax.

Apoptosis of blood neutrophils from healthy donors was studied under conditions of cell culturing with different concentrations of H(2)O(2), selective NO synthase inhibitor, and inductor of NO synthesis (L-arginine). In vitro incubation of neutrophilic leukocytes with 5 mM H(2)O(2) led to activation of the apoptotic program in neutrophils, which was seen from increased content of Bax protein in the cells and increased number of apoptotic cells in the culture. Increased content of annexin-positive cells after incubation of neutrophil culture with NO synthase inhibitor suggests involvement of NO in the regulation of neutrophil apoptosis under conditions of oxidative stress, while L-arginine prevented H(2)O(2)-induced programmed cell death.

HSV-1 ICP27, an immediate early protein of herpes simplex virus type 1, is involved in viral replication, transcriptional activation, RNA stability, apoptosis, and reactivation from viral latency. The reactivation from viral latency is closely related to apoptosis and oxidative stress. To understand the effect of ICP27 upon apoptosis, we tested for cell death of ICP27-expressing cells (3-3) in the presence of hydrogen peroxide. Under oxidative stress, 3-3 cells were sensitive to death, displaying typical apoptosis features such as oligonucleosomal DNA fragmentation, chromatin condensation, and G0/G1 accumulation. To dissect the sensitizing mechanism of ICP27 in apoptosis, we analyzed the level of intracellular reactive oxygen species (ROS) in 3-3 cells. We found that 3-3 cells exhibited increased ROS levels compared to Vero cells devoid of ICP27. We also observed that the increased levels of intracellular ROS in 3-3 cells were caused by disturbances in antioxidant enzymes. In 3-3 cells, the elevated ROS increased the AP-1 activity, subsequently the expression of Bax increased, and the expression of Bcl2 was reduced. In addition, 3-3 cells were sensitive to various apoptotic agents. Taken together, these results indicate that HSV-I ICP27 sensitizes the cells to apoptosis by elevating the intracellular levels of ROS.

Studies of expression of BCL-2 gene family revealed abnormal regulation of biosynthesis of apoptosis-related proteins in tumour cells involved in the development and progress of neoplastic diseases. Expression of BCL-2 proteins in highly differentiated gastric and colonic tumours was roughly 1.2 times lower than in the normal cells. A 3.5-fold rise in BCL-2 expression was documented in a group of moderately differentiated adenocarcinomas and undifferentiated tumours. The most striking (9-fold) difference between BCL expression in untransformed and atypical cells was recorded in moderately differentiated metastatic colonic adenocarcinoma. Immunohistochemical studies of BAX expression in untransformed and atypical gastric and colonic cells demonstrated activation of apoptosis-inducing mechanisms in the pathologically changed tissue. Investigations with the use of SSCP showed that 20% of the patients had BAX gene mutations affecting codons 38 to 41 of exone 3. This region was found to contain octadeoxyguanosine G8 sequence. The mutations were caused by deletion of G7 or insertion of G9.

Apoptosis is the vital issue of Biology and Medicine. Recent concept of molecular and cellular mechanisms of apoptosis--a well-controlled form of cell death was reviewed. The aim of a review was to broaden knowledge of apoptosis mechanism and to reveal molecular targets for the modulation of these processes. The data on the apoptosis was analyzed. The biological role of physiological cell death in normal state and in different human pathologies is described. The literature data showed that many molecular mechanisms of apoptosis are still unknown. Three mechanisms are actually known to be involved in the apoptotic process: a receptor-ligand mediated mechanism, a mitochondrial pathway and a mechanism in which the endoplasmic reticulum plays a central role. Morphological and biochemical definitions of poptosis are presented. An original scheme of apoptosis mechanisms is constructed. The term "mediators of poptosis" is introduced. Extra cellular and intracellular mechanisms of apoptosis are examined. The special attention is paid to mitochondrial factors of apoptosis, Ca(2+)-ions, and proteins (Bcl-2, Bax, p-53).