Zoran Milosavljevic

Chrysin induces apoptosis in peripheral blood lymphocytes isolated from human chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) develops due to an imbalance between apoptosis and proliferation of B lymphocytes. Chrysin induced apoptosis in leukemia cell lines such as U937, MO7e, THP-1 and HL-60, but there has not yet been data demonstrating the apoptotic effect of chrysin on CLL cells. Therefore, in our investigation we examined the cytotoxicity of chrysin against two leukemia cell lines, MOLT-4 and JVM-13, peripheral blood lymphocytes isolated from B-CLL patients and peripheral blood mononuclear cells (PBMC) from healthy individuals in vitro. The effect of chrysin on viability of MOLT-4 and JVM-13 cell lines, B-CLL cells derived from 28 patients and PBMC from 16 healthy subjects was determined by MTT assay. The type of cell death induced by chrysin was verified by Annexin V/7AAD assay and acridine orange and ethidium bromide (AO/EB) staining assay. Intracellular localisation and endogenic expression of apoptotic proteins including Bax, Bcl-2, cytochrome c and caspase-3 were determined by flow cytometry and fluorescent microscopy. Our results demonstrated that exposure of MOLT-4, JVM-13 cell lines and B-CLL cells to the concentration of chrysin of 10μM and higher selectively decreased viability of cells in this cell population, but not in the PBMC derived from healthy subjects; LC50 values of chrysin for B-CLL cells were 51μM for 24 hours and 32μM for 48 hours of incubation, respectively. Our findings demonstrated that chrysin induces the activation of proapoptotic Bax and decreases the expression of antiapoptotic Bcl-2 protein, releases cytochrome c from mitochondria into cytosol and cleavages/activates caspase-3, subsequently leading to the activation of apoptosis of B-CLL cells. Together, these findings suggest that chrysin selectively induces apoptosis of peripheral blood lymphocytes isolated from human chronic lymphocytic leukemia patients via mitochondrial pathway in vitro and that it might have a promising role as a potential future antileukemic remedy.

Induction of mitochondrial apoptotic pathway by raloxifene and estrogen in human endometrial stromal ThESC cell line

Introduction Endometrial hyperplasia is a condition that occurs as a result of hormonal imbalance between estrogen and progesterone. Morphological disturbance of endometrial cells occurs consequently leading towards endometrial cancer. In therapy of endometrial hyperplasia SERMs are used to supress effects of locally high estrogen level in uterus. There is strong evidence suggesting that estrogen could be involved in cell death – apoptosis. There are no experimental data demstrating the direct apoptotic effect of both raloxifene and estrogen on the ThESC cell line. The aim of our study wa sto investigate both cytotoxic and apototic mechanism of raloxifene and estrogen – induced death in the ThESC cell line. Material and methods In order to determine their cytotoxic and apoptotic effects, various doses of raloxifene and estrogen were applied to the ThESC cell line for 24 h. After the treatment MTT assay, FACS analysis and immunofluoroscence method were conducted. Results The results of this study for the first time demonstrated the cytotoxic and apoptotic effects of raloxifene and estrogen on human endometrial stromal cell line suggesting the involvement of the inner, mitochondrial apoptotic pathway. Conclusions Our results demonstrated apoptotic effects of investigated drugs in the ThESC cell line through increasing the Bax/Bcl-2 ratio and activation of caspase 3.

The Effects of High Doses of Nandrolone Decanoate on Cardiac Muscle Tissue

Abstract In recent decades, steroid abuse has become very popular and widespread among professional and recreational athletes. The aim of this study was to examine the chronic effects of training combined with high doses of nandrolone decanoate on cardiac muscle tissue. The study included 32 Wistar albino rats divided into 4 groups: control (T-N-), steroid (T-N+), exercisetraining (T+N-) and exercise plus steroid (T+N+) groups. The T+N- and T+N+ group swam for 4 weeks, 1 hour per day, 5 days per week. The N+ (nandrolone positive groups) received nandrolone decanoate (20 mg/kg) once per week, subcutaneously. After 4 weeks of training, the rats were sacrificed. Heart biopsy specimens were routinely fixed and embedded in paraffin. Fivemicrometre thick sections were stained with haematoxylin and eosin (H/E) and Masson-Trichrome dyes. Captured microscopic images were processed by special software for image analysis to quantify results. Our results showed that the combination of nandrolone and training causes left ventricular wall thickening of 30%. Average cardiac muscle cell longitudinal diameter was increased by 6% in the T-N+ group, by 16% in the T+N- group and by 25% in the T+N+ group. The cross sectional muscle cell area was increased in the T+N+ group by 33%. Heart collagen content was increased in the nandrolone group compared to the control group by 261%. Collagen content was decreased in the T+N+ group by 34%. High doses of AAS induced left ventricle hypertrophy and excessive heart collagen deposition.

Enhanced cytotoxicity and apoptosis by raloxifene in combination with estrogen and methotrexate in human endometrial stromal cells

Endometrial hyperplasia is a condition that may lead to the development of endometrial carcinoma. Initially, changes of the endometrium are caused by the estrogens hyperstimulation that may lead to the development of an irregular bleeding and the infertility problems. Therapy of endometrial hyperplasia is limited to medical and surgical approaches. During the past decade, the new types of drugs were developed for the treatment of the endometrial hyperplasia. Here, for the first time, we investigated the cytotoxic effects of the various combinations of estrogen, raloxifene, and methotrexate in human ThESC cell line as a possible potential treatment of the endometrial hyperplasia. Our aim was to investigate and to determine the most efficient combination of investigated drugs in ThESC cells during 24‐hr period using MTT assay, FACS analysis, and immunofluorescence staining. Our results demonstrated that the combination of raloxifene with methotrexate efficiently induced both the cytotoxicity and apoptosis in ThESC cells when compared to their single effect, as well as to the effect of combined treatment of raloxifene with estrogen. The application of the low doses of methotrexate combined with raloxifene offers all advantages of a potential beneficial antitumor match in cancer chemoprevention and therapy.

The mineral content of the hard dental tissue of mesiodens

OBJECTIVE Mesiodens is the most common form of supernumerary tooth mainly located between the maxillary central incisors. Its etiology is not completely understood but both genetic and environmental factors are assumed. The degree of mineralization and inorganic element content in hard tooth tissues is poorly understood as well as is the durability and suitability for allo- and auto-transplantation. Therefore aim of this study was to examine the content of inorganic elements. MATERIALS AND METHODS This study included 26 mesiodens teeth and 26 normal central incisor teeth as controls. All specimens were prepared for SEM/EDS analysis which was aimed at specific sites on the enamel, dentine and cementum in order to evaluate the weight percentage and ratio of important inorganic elements. RESULTS and Conclusion. The results showed that there was a difference in the weight percentage of selected inorganic elements (calcium, phosphorus, oxygen, carbon, magnesium and sodium) in all three types of dental hard tissues but the differences were mostly expressed in the cementum tissue. The statistical analysis showed that the differences were marginally significant especially for calcium and phosphorus values and ratio in the enamel and dentine. The carbon and magnesium content in all three hard tissues showed the most differences, but overall, the hard tissues mineral content of the mesiodens did not differs significantly from healthy teeth.

Nandrolone decanoate and physical activity affect quadriceps in peripubertal rats

Anabolic androgenic steroids (AASs) are synthetic analogs of testosterone often used by athletes to increase the skeletal muscle mass. Our goal was to examine the effects of physical activity and physical activity combined with supraphysiological doses of nandrolone on functional morphology of the quadriceps muscle. The study included 32 peripubertal Wistar rats, divided into 4 groups: control (T-N-), nandrolone (T-N+), physical activity (T+N-) and physical activity plus nandrolone (T+N+) groups. The T+N- and T+N+ group swam for 4 weeks, 1 h/day, 5 days/week. The T-N+ and T+N+ groups received nandolone decanoate (20 mg/kg b.w.) once per week, subcutaneously. Subsequently, the rats were sacrificed and muscle specimens were prepared for the processing. Tissue sections were histochemically and immunohistochemically stained, while the image analysis was used for quantification. Longitudinal diameter of quadriceps muscle cells was increased for 21% in T-N+, for 57% in T+N- and for 64% in T+N+ group while cross section muscle cell area was increased in T-N+ for 19%, in T+N- for 47% and in T+N+ group for 59%, compared to the control. Collagen fibers covered area was increased in T-N+ group for 36%, in T+N- for 109% and in T+N+ group for 159%, compared to the control. Erythrocyte depots were decreased in T-N+ group and increased in T+N- and T+N+ group, in comparison with T-N-. VEGF depots were increased in all treated groups. Chronic administration of supraphysiological doses of AASs alone or in combination with physical activity induces hypertrophy and significant changes in the quadriceps muscle tissue structure.

Morphology of Human Nucleus Accumbens Neurons Based on the Immunohistochemical Expression of Gad67

Abstract The nucleus accumbens is a part of the ventral striatum along with the caudate nucleus and putamen. The role of the human nucleus accumbens in drug addiction and other psychiatric disorders is of great importance. The aim of this study was to characterize medium spiny neurons in the nucleus accumbens according to the immunohistochemical expression of GAD67. This study was conducted on twenty human brains of both sexes between the ages of 20 and 75. The expression of GAD67 was assessed immunohistochemically, and the characterization of the neurons was based on the shape and size of the soma and the number of impregnated primary dendrites. We showed that neurons of the human nucleus accumbens expressed GAD67 in the neuron soma and in the primary dendrites. An analysis of the cell body morphology revealed the following four different types of neurons: fusiform neurons, fusiform neurons with lateral dendrites, pyramidal neurons and multipolar neurons. An immunohistochemical analysis showed a strong GAD67 expression in GABAergic medium spiny neurons, which could be classifi ed into four different types, and these neurons morphologically correlated with those described by the Golgi study.

DIFFERENTIAL HISTOMORPHOMETRIC CHANGES IN NORMAL AND INFLAMED GINGIVAL EPITHELIUM

Introduction and aim: In recent decades, many factors such as smoking, unhealthy diet as well as high alcohol intake were marked as risk factors that can lead to increased incidence of malignant alterations, gingivitis, periodontal disease and other oral epithelium pathological changes. Having in mind that in the group of non-malignant and non-dental oral pathology gingivitis and periodontal disease are the most common oral mucosa alterations aim of our research was to investigate histomorphometric characteristics of healthy and altered oral and gingival epithelium. Material and methods: Tissue samples of 24 oral and gingival mucosa specimens were collected. Samples were fixed in 10% buffered paraformaldehyde, routinely processed and embedded in paraffin blocks. From each block sections 5 micrometer thin were made and standard H/E staining as well as immunocytochemical detection of Ki-67 proliferation marker and CD79a lymphocyte marker were performed. Measurements and image analysis was performed with Image Pro Plus software (Media Cybernetics, USA) and Axiovision (Ziess, USA). Results: We showed that inflamed gingival epithelium is increasing its thickness in proportion to the severity of adjacent inflammation. Furthermore, mitotic index is rising (up to 132%) in the same manner as well as basal lamina length (up to 70%) when normal and inflamed gingiva is compared. Architecture of epithelial ridges is changed from straightforward to mesh-like. Conclusion: Assessment of the free gingival epithelium thickness is directly related to the severity of the inflammation process in gingiva.

Enhancement Of Dermal Fibroblast Isolation Method

ABSTRACT Cultivated fibroblasts have been widely used in a large number of in vitro studies. Although they readily proliferate under cell culture conditions, improvements in methods for their isolation are necessary. Here, we present our modified enzyme digestion method and compare its efficiency with commonly used techniques. Three foreskin samples from young, middle-aged and old donors were used. The classical explant, standard enzyme digestion method with collagenase and our improved enzyme digestion method were compared for efficiency of fibroblast isolation and the time needed to achieve 95% confluence in a 30-mm Petri dish. The explant method was the slowest to achieve fibroblast confluence, especially with the tissues from the older donors (up to 23 days). With the standard enzyme digestion method, the skin tissue was partially digested, but the fibroblasts reached confluence much faster (the younger donor cells needed approximately 7 days to reach confluence). Our modified “mixed” enzyme digestion method was the fastest (the fibroblasts from the younger donors needed up to 5 days to reach confluence). For studies requiring the primary isolation and cultivation of dermal fibroblasts, the best method to achieve this goal is the tissue digestion method with the multiple enzyme solution.

Histochemical characterization of epithelial ovarian cancer

Objective. Study was designed to reveal the prognostic significance of Ki-67, IgA and mucin secretion in ovarian neoplasms. Methods. Samples of ovarian tumours of 42 female patients were routinely processed and stained with anti-Ki67 and anti- IgA antibodies as well as with histochemistry methods for mucin verification. Results. In our study proliferation marker Ki-67 was proven to be a good prognostic tool of the degree of the cellular atypia. High immunoglobulin A expression was verified in the epithelium and along the luminal border of well differentiated tumors. Histochemical mucin analysis showed quantitative and qualitative changes in mucin secretion that correlates with the degree of tumor differentiation. Conclusion. Ki-67, IgA and epithelial mucins are valid prognostic factors in ovarian neoplasms.