Bone marrow morphology during haematopoietic stem cell mobilisation with cyclophosphamide in mice

The aim of the study was to examine the morphology of the bone marrow of mice after stimulation with cyclophosphamide (Cy). The experimental mice were given a single intraperitoneal injection with 250 mg/kg bw cyclophosphamide. After 2, 4 and 6 days of experiment the femurs were obtained for morphological study. On the 2nd day after the mobilisation of the mice with Cy destruction of the bone marrow was observed with a decrease in the haematopoietic compartment and an increase in the area occupied by sinusoids filled with erythrocytes. Erythrocytes were located among the haematopoietic cells, which indicated that the endothelial barrier had been disrupted. On the 4th day after treating the mice with Cy, repair processes in the bone marrow were conducted, including macrophages. The cells filled with haemosiderin migrated from the extravascular compartment of the bone marrow into the lumen of the sinusoids. There were proliferating cells among the haematopoietic cells. On the 6th day the morphology of the bone marrow was similar to the morphology of that in the control mice. However, more haematopoietic cells were visible compared to the control bone marrow. The presence of an increased number of leucocytes in the sinusoid lumen in comparison with the control suggested that at that time the migration of haematopoietic cells from the bone marrow had been initiated

Possible involvement of microtubules and microfilaments of the epididymal epithelial cells in 17beta-estradiol synthesis.

The rat epididymal epithelial cells revealed features of steroidogenic cells and released 17beta-estradiol (E2) into the culture medium. In steroidogenic cells, elements of the cytoskeleton due to their influence on organelle distribution are implicated in the regulation of steroidogenesis. In the present study, the morphology of cultured epididymal epithelial cells in light, scanning and transmission electron microscopes was evaluated. The organization of microtubules and microfilaments revealed by fluorescence microscopy, and the concentration of E2 in cultured medium were also studied. The epididymal epithelial cells were cultured in different conditions: in the medium with or without exogenous testosterone (T) and in the co-culture with Leydig cells as a source of androgens. The cells in co-culture located close to Leydig cells were rich in glycogen, PAS-positive substances and lipid droplets, in higher amount than the cells cultured with addition of exogenous testosterone. Stress fibers and microtubules of epididymal epithelial cells cultured with exogenous T and in co-culture with Leydig cells presented typical structure, and numerous granular protrusions appeared on the surface of the cells. Disorganization of microtubules and shortening of stress fibers as well as the smooth cell surface deprived of granular protrusions were observed in the epididymal epithelial cells cultured without T. Change of the cytoskeleton organization caused by the absence of androgen in culture medium resulted in an increased E2 secretion

DHT deficiency perturbs the integrity of the rat seminiferous epithelium by disrupting tight and adherens junctions

In rats with a DHT deficiency induced by finasteride, morphological changes in the seminiferous epithelium were observed. The structural alterations were manifested by the premature germ cells sloughing into the lumen of seminiferous tubules. The etiology of this disorder could be connected with intercellular junctions disintegration. We showed in the immunohistochemical study the changes in expression of some proteins building tight and adherens junctions. The depression of N-cadherin, β-catenin and occludin immunoexpressions could be the reason for the release of immature germ cells from the seminiferous epithelium. However, the observed increase of the immunohistochemical reaction intensity of vinculin, one of the cadherin/catenin complex regulators, could be insufficient to maintain the proper function of adherens junctions. The hormonal imbalance appears to influence the pattern of expression of junctional proteins in the seminiferous epithelium. It could lead to untimely germ cells sloughing, and ultimately could impair fertility. (Folia Histochemica et Cytobiologica 2011, Vol. 49, No. 1, 62–71

Antioxidative properties of phenolic compounds and their effect on oxidative stress induced by severe physical exercise

Extensive research has found strongly increased generation of reactive oxygen species, free radicals, and reactive nitrogen species during acute physical exercise that can lead to oxidative stress (OS) and impair muscle function. Polyphenols (PCs), the most abundant antioxidants in the human diet, are of increasing interest to athletes as antioxidants. Current literature suggests that antioxidants supplementation can effectively modulate these processes. This overview summarizes the actual knowledge of chemical and biomechanical properties of PCs and their impact as supplements on acute exercise-induced OS, inflammation control, and exercise performance. Evidence maintains that PC supplements have high potency to positively impact redox homeostasis and improve skeletal muscle\u27s physiological and physical functions. However, many studies have failed to present improvement in physical performance. Eleven of 15 representative experimental studies reported a reduction of severe exercise-induced OS and inflammation markers or enhancement of total antioxidant capacity; four of eight studies found improvement in exercise performance outcomes. Further studies should be continued to address a safe, optimal PC dosage, supplementation timing during a severe training program in different sports disciplines, and effects on performance response and adaptations of skeletal muscle to exercise

Bone marrow morphology during haematopoietic stem cell mobilization with G-CSF in mice

The aim of the work was to examine the morphology of the bone marrow of mice during stimulation with G-CSF. Experimental Balb C mice were daily injected subcutaneously with 250 μg/kg b.w. G-CSF (Neupogen). After 2, 4 and 6 days of the experiment femurs were obtained for morphological study. On day 2 of the mobilization the amount of haematopoietic cells in the bone marrow increased and dilatation of the sinusoids was observed. Only single leukocytes were observed in the lumen of the vessels. There were numerous leukocytes in the lumen of the sinusoids on day 4 of the mobilization. The morphology of the bone marrow on day 6 was similar to that of the control. Mobilization of mice with G-CSF resulted in migration of haematopoietic cells from the bone marrow and the process is most pronounced on day 4

Effect of hCG on the morphology of rat epididymal epithelial cells in vitro

The epididymis is an androgen-dependent organ. The hormones regulate the morphology and secretory activity of the epididymal epithelial cells. The cells in vitro resume their function as in vivo and also reveal features of steroidogenic cells. It can be expected that, as with Leydig cells, the morphology and function of the cells can be regulated by LH/hCG. The aim of the study was to assess the morphology of epididymal epithelial cells in vitro after stimulation with hCG. The experiment was performed on cells isolated from sexually mature rats. The epididymal epithelial cells were cultured in a medium with the addition of dihydrotestosterone (DHT). Moreover, the cells were cultured in the medium with DHT and without DHT but enriched with hCG. The epididymal epithelial cells cultured with DHT formed a monolayer and accumulated glycogen, a PAS-positive substance and lipid droplets. The cells cultured without DHT were stellate in shape and low in glycogen and PASpositive substance but they contained lipid droplets. The morphology of epididymal epithelial cells cultured without DHT but after stimulation with hCG was similar to the morphology of the cells cultured with DHT. This was the first sign that the morphology of the cells can be influenced by hCG

Rat epididymal epithelial cells and 17beta-estradiol synthesis under hCG stimulation in vitro.

Epithelial cells of human and animal epididymis display features of steroidogenic cells. Rat epididymal epithelial cells in vitro produce androgens which are converted to 17beta-estradiol, and released into the medium. The regulation of the epididymal steroidogenesis is not fully understood but it could be expected that it remains under LH influence. In previous study we observed that the morphology of rat epididymal epithelial cells in vitro was affected by hCG and the increase of amount of lipid droplets, glycogen and PAS-positive substances was observed. The present studies show the organelles which take part in synthesis of steroids in rat epididymal epithelial cells in vitro and the effect of hCG on E2 synthesis. The cells were cultured in the medium with/without DHT and without DHT in supplementation with hCG. After hCG stimulation the amount of an active mitochondria were increased when compared to the amount of mitochondria in the epididymal epithelial cells cultured without DHT. Ultrastructure of the cells was similar to the cells cultured with DHT, while the cytoplasm of the cells cultured without DHT was disorganized. The synthesis of 17beta-estradiol was stimulated by hCG, that exerted its effect through LH/hCG receptors, localized in the epididymal epithelial cells

The immunoexpression of androgen receptor, estrogen receptors alpha and beta, vanilloid type 1 receptor and cytochrome p450 aromatase in rats testis chronically treated with letrozole, an aromatase inhibitor

The function of testis is under hormonal control and any disturbance of hormonal homeostasis can lead to morphological and physiological changes. Therefore the aim of the study was to investigate the expression of androgen and estrogen receptors (AR, ERs), vanilloid receptor (TRPV1), cytochrome P450 aromatase (P450arom), as well as apoptosis of cells in testis of adult rats chronically treated with letrozole (LT), a non-steroidal aromatase inhibitor, for 6 months. The testicular tissues were fixed in Bouin’s fixative and embedded in paraffin. Immunohistochemistry with monoclonal antibodies (abs) against AR, ERa, P450arom, and polyclonalabs against ERβ, TRPV1, caspase-3 was applied. Long-lasting estradiol deficiency, as an effect of LT treatment, produced changes in the morphology of testis and altered the expression of the studied receptors in cells of the seminiferous tubules and rate of cell apoptosis. The immunostaining for AR was found in the nuclei of Sertoli cells and the cytoplasm of spermatogonia and spermatocytes in III–IV stages of the seminiferous epithelium cycle. The intensity of staining for P450arom was lower in the testis of LT-treated rats as compared to control animals. The immunofluorescence of ERα and ERβ was observed exclusively in the nuclei of Leydig cells of LT-treated rats. There were no changes in localization of TRPV1, however, the intensity of reaction was stronger in germ cells of the seminiferous epithelium after LT treatment. The apoptosis in both groups of animals was observed within the population of spermatocytes and spermatids in II and III stages of the seminiferous epithelium cycle. In testis of LT-treated rats the immunoexpression of caspase-3 was additionally found in the germ cells in I and IV stages, and Sertoli, myoid and Leydig cells. In conclusion, our results underline the important role of letrozole treatment in the proper function of male reproductive system, and additionally demonstrate that hormonal imbalance can produce the morphological abnormalities in testis

Morphology of the bone marrow, spleen and liver during hematopoietic cell mobilization with cyclophosphamide in mice.

Cyclophosphamide (CY), the agent with cytoreductive activity, is widely exploited in cancer chemotherapy, and can be used alone or in combination with various cytokines and growth factors to stimulate the egress of hematopoietic stem/progenitor cells (HSPC) from the BM compartment. The aim of the present study was to exam the morphology and ultrastructure of the bone marrow, spleen and liver of mice injected intraperitoneally with a single dose of cyclophosphamide (200 mg/kg bw) and the localization of cells expressing markers of early hematopoietic cells in studied organs and the peripheral blood. We observed that the CY-induced morphological changes in the BM and spleen were reconstructed on day 4. of experiment, and the spleen was repopulated by HSPC on the 6th day. In this time, the highest number of c-Kit-R-positive cells was determined by flow cytometry in the peripheral blood. The results confirmed, that the egress of HSPC from the bone marrow into the peripheral blood was delayed compared to mice treated with G-CSF or GCS-F plus CY