Toxicity of bisphenol A and its replacements in the mice Leydig cells in vitro.

The aim of the study was to examine the potential impacts of bisphenol A (BPA) and its analogues BPB, BPF, and BPS on mice TM3 Leydig cells, with respect to basal cell viability parameters such as metabolic activity, cell membrane integrity, and lysosomal activity after 48-h exposure. In addition, monitoring of potential bisphenol´s actions included evaluation of ROS production and gap junctional intercellular communication (GJIC) complemented by determination of testosterone secretion. Obtained results revealed significant inhibition in mitochondrial activity started at 10 microg/ml of bisphenols after 48-h exposure. Cell membrane integrity was significantly decreased at 5 microg/ml of BPA and BPF and 10, 25, and 50 microg/ml of BPA and BPS. The lysosomal activity was significantly affected at 10, 25, and 50 microg/ml of applied bisphenols. A significant overproduction of ROS was recorded mainly at 5 and 10 microg/ml of tested compounds. In addition, significant inhibition of GJIC was observed at 5 microg/ml of BPB followed by a progressive decline at higher applied doses. In the case of testosterone production, a significant decline was confirmed at 10, 25 and 50 microg/ml.

Is there impact of the SARS-CoV-2 pandemic on steroidogenesis and fertility?

In December of 2019, several cases of unknown atypical respiratory diseases emerged in Wuhan, Hubei Province in China. After preliminary research, it was stated that the disease is transmittable between humans and was named COVID-19. Over the course of next months, it spread all over the world by air and sea transport and caused a global pandemic which affects life of everyone now-a-days. A large number of countries, have since been forced to take precautions such as curfews, lockdowns, wearing facemasks etc. Even with vaccines being produced in mass numbers, lack of targeted therapy continues to be a major problem. According to studies so far it seems that elderly people are more vulnerable to severe symptoms while children tend to by asymptomatic or have milder form the disease. In our review, we focused on gathering data about the virus itself, its characteristics, paths of transmission, and its effect on hormone production and secretion. In such, there is insufficient information in the literature worldwide, especially the ones that focus on the effect of COVID-19 on individual organs systems within the human body. Hence, the present evidence-based study focused on the possible effects of COVID-19 on adrenal gland and gonads i.e. on the process of steroidogenesis and fertility.

Human Adrenocortical Carcinoma (NCI-H295R) Cell Line as an In Vitro Cell Culture Model for Assessing the Impact of Iron on Steroidogenesis.

The aim of this in vitro study was to examine the dose-dependent effects of iron as a potential endocrine disruptor in relation to the release of sexual steroid hormones by a human adrenocortical carcinoma (NCI-H295R) cell line. The cells were exposed to different concentrations (3.90, 62.50, 250, 500, 1000 µM) of FeSO4.7H2O and compared with the control group (culture medium without FeSO4.7H2O). Cell viability was measured by the metabolic activity assay. Quantification of sexual steroid production was performed by enzyme-linked immunosorbent assay. Following 48 h culture of the cells in the presence of FeSO4.7H2O, significantly (P < 0.001) increased production of progesterone was observed at the lowest concentration (3.90 µM) of FeSO4.7H2O, whereas the lowest release of progesterone by NCIH295R cells was noted after addition of 1000 µM of FeSO4.7H2O, which did not elicit cytotoxic action (P > 0.05). Testosterone production was substantially increased at the concentrations ≤ 62.50 µM of FeSO4.7H2O. Lower levels of testosterone were recorded in the groups with higher concentrations (≥ 250 µM) of FeSO4.7H2O (P > 0.05). The presented data suggest that iron has no endocrine disruptive effect on the release of sexual steroid hormones, but its toxicity may be reflected at other points of the steroidogenesis pathway.

The effect of Apium graveolens L., Levisticum officinale and Calendula officinalis L. on cell viability, membrane integrity, steroidogenesis, and intercellular communication in mice Leydig cells in vitro.

Several plants have the potential to protect essential reproductive processes such as spermatogenesis or steroidogenesis, however, effective concentrations and main mechanisms of action are still unknown. This in vitro study was aimed to assess the effects of Apium graveolens L., Levisticum officinale, and Calendula officinalis L. extracts on the structural integrity, functional activity and gap junctional intercellular communication (GJIC) in mice Leydig cells. TM3 cells were grown in the presence of experimental extracts (37.5; 75; 150 and 300 µg/ml) for 24 h. For the present study, high-performance liquid chromatography analysis was used to quantify flavonoids or phenolic acids. Subsequently, Leydig cell viability was assessed by alamarBlue assay, while the cell membrane integrity was detected by 5-carboxyfluorescein diacetate-acetoxymethyl ester. The level of steroid hormones production was determined by enzyme-linked immunosorbent assay. Additionally, GJIC was assessed by scalpel loading/dye transfer assay. According to our results, Apium graveolens L. significantly increased the viability and cell membrane integrity at 75 µg/ml (109.0±4.3%) followed by a decline at 300 µg/ml (89.4±2.3%). In case of Levisticum officinale and Calendula officinalis L. was observed significant decrease at 150 µg/ml (88.8±11.66%; 87.4±6.0%) and 300 µg/ml (86.2±9.3%; 84.1±4.6%). Furthermore, Apium graveolens L. significantly increased the progesterone and testosterone production (75 and 150 µg/ml) however, Levisticum officinale and Calendula officinalis L. significantly reduced steroid hormones synthesis at 150 and 300 µg/ml. Finally, the disturbance of GJIC was significantly affected at 300 µg/ml of Levisticum officinale (82.5±7.7%) and Calendula officinalis L. (79.8±7.0%). The balanced concentration ratio may support the Leydig cell function, steroidogenesis as well as all essential parameters that may significantly improve reproductive functions.

The effect of immunocastration on adipose tissue deposition and composition in pigs.

Immunocastrated pigs (IC) exhibit intensive fat deposition after immunisation, but the underlying mechanisms of intensified fat metabolism and deposition are not yet fully understood. Moreover, there is also a lack of comparative studies performed on IC, entire males (EM) and surgical castrates (SC). The main objective of our research was, therefore, to characterise the adipose tissue from the quantitative, histo-morphological and biochemical perspectives in IC 5 weeks after their immunisation in comparison to EM and SC. Immunocastrated pigs had an intermediate position in carcass fatness traits between EM (the leanest) and SC (the fattest). The histo-morphological traits of the subcutaneous adipose tissue of IC were similar to those of SC and differed from those of EM; i.e., they exhibited larger adipocytes in the outer backfat and a larger lobulus surface area in both backfat layers than EM. Intensive fat tissue development in IC was corroborated with higher activities of lipogenic enzymes (i.e., fatty acid synthase, malic enzyme, glucose 6-phosphate dehydrogenase, citrate cleavage enzyme), which was especially pronounced in the subcutaneous adipose tissue of IC (1.5- to 2.7-fold higher activity than in EM or SC). The fatty acid composition of the backfat in IC was similar to that in EM pigs. Both IC and EM exhibited less saturated and more polyunsaturated fatty acids than SC. In contrast, the fatty acid composition of the intramuscular fat of longissimus dorsi muscle in IC pigs was more similar to SC than to EM (higher monounsaturated and lower polyunsaturated fatty acid content in IC and SC than EM). In this study, it was demonstrated that immunocastration notably influenced lipid metabolism. This was shown by increased quantity of lipid depots and with changes in adipose tissue cellularity compared to EM, with changes in the fatty acid composition of the intramuscular fat and enhanced lipogenic activity compared to both EM and SC. These results provide new insights into the specificity of adipose tissue development and deposition in IC compared to EM and SC.

Men´s reproductive alterations caused by bisphenol A and its analogues: a review.

Male reproductive functions are an important area affecting men´s overall health and well-being. However, during the last years, there has been observed increasing incidence of male reproductive issues. The radical growth has been recorded parallelly with a massive expanse of industrialization and agricultural chemigation. Many groups of experts have begun to identify several potential factors and substances that may have adverse effects on men´s reproductive health. Since then, xenobiotics have become a major concern of many scientific studies. There is evidence that most of them have multigenerational and transgenerational effects on reproductive health, which is a serious problem for our population. Bisphenol A could be considered as one of the most studied endocrine disruptors. Until now, several negative effects of bisphenol A were associated with reduced weight testes, histological alterations, impairment spermatogenesis, and steroidogenesis as well as with testes or prostate cancer. Due to convincing evidence, bisphenol A has been started to replace by its analogues such as bisphenol B, S, F, in order to eliminate and suppress the risk of exposure to bisphenol A. However, it seems that a lack of toxicological analyses allows using of these hazardous substances in daily life. Their harmful effect was confirmed by the animal in vitro and in vivo models, while the epidemiological studies monitoring the impact of bisphenol analogues on men's reproductive health are markedly limited. This review provides information about the effects of bisphenol on reproductive health in men. At the same time, it is focused on physiological aspects of sperm viability, steroid hormone secretion, sperm motility, or testes histology in relation to bisphenols exposure.

In vitro assessment of the impact of nickel on the viability and steroidogenesis in the human adrenocortical carcinoma (NCI-H295R) cell line.

Nickel is a ubiquitous environmental pollutant, which has various effects on reproductive endocrinology. In this study, human adrenocortical carcinoma (NCI-H295R) cell line was used as an in vitro biological model to study the effect of nickel chloride (NiCl2) on the viability and steroidogenesis. The cells were exposed to different concentrations (3.90; 7.80; 15.60; 31.20; 62.50; 125; 250 and 500 microM) of NiCl2 and compared with control group (culture medium without NiCl2). The cell viability was measured by the metabolic activity assay. Production of sexual steroid hormones was quantified by enzyme linked immunosorbent assay. Following 48 h culture of the cells in the presence of NiCl2 a dose-dependent depletion of progesterone release was observed even at the lower concentrations. In fact, lower levels of progesterone were detected in groups with higher doses (>/=125 microM) of NiCl2 (P<0.01), which also elicited cytotoxic action. A more prominent decrease in testosterone production (P<0.01) was also noted in comparison to that of progesterone. On the other hand, the release of 17beta-estradiol was substantially increased at low concentrations (3.90 to 62.50 microM) of NiCl2. The cell viability remained relatively unaltered up to 125 microM (P>0.05) and slightly decreased from 250 microM of NiCl2 (P<0.05). Our results indicate endocrine disruptive effect of NiCl2 on the release of progesterone and testosterone in the NCI-H295R cell line. Although no detrimental effect of NiCl2 (

Investigation of the Properties and Effects of Salvia Officinalis L. on the Viability, Steroidogenesis and Reactive Oxygen Species (ROS) Production in TM3 Leydig Cells in Vitro.

The aim of our study was to reveal the in vitro effects of Salvia officinalis L. (37.5, 75, 150, 200, 250, 300 and 600 µg/ml) extract on the TM3 Leydig cell viability, membrane integrity, steroidogenesis and reactive oxygen species production after 24 h and 48 h cultivation. For the present study, the extract prepared from Salvia officinalis L. leaves was analysed by high performance liquid chromatography (HPLC) for selected flavonoids and phenolic acids followed by a determination of its free radicals scavenging activity (DPPH). Furthermore, Leydig cell viability was assessed by the mitochondrial toxicity assay (MTT), while the membrane integrity was evaluated by 5- carboxyfluorescein diacetate-acetoxymethyl ester (5-CFDA-AM). The level of steroid hormones was performed by enzyme-linked immunosorbent assay (ELISA) from the culture media, while the superoxide radical generation was measured by the nitroblue tetrazolium chloride (NBT) assay. The results show that experimental concentrations did not damage the cell membrane integrity and viability when present at below 300 µg/ml, it was only at 600 µg/ml that a significant (P<0.05) cell viability decline was observed after a 48 h cultivation. A significant (P<0.05) stimulation of testosterone secretion was recorded at 250 µg/ml for 24 h, while the prolonged cultivation time significantly (P<0.05) increased the testosterone and progesterone production at 150, 200, 250 and 300 µg/ml. Furthermore, none of the selected doses exhibited significant ROS-promoting effects however, the highest dose of Salvia initiated the free radical scavenging activity in cultured mice Leydig cells.

Assessment of the effective impact of bisphenols on mitochondrial activity and steroidogenesis in a dose-dependency in mice TM3 Leydig cells.

The increasing worldwide production of bisphenols has been associated to several human diseases, such as chronic respiratory and kidney diseases, diabetes, breast cancer, prostate cancer, behavioral troubles and reproductive disorders in both sexes. The aim of the present in vitro study was to evaluate the potential impact bisphenols A, B, S and F on the cell viability and testosterone release in TM3 Leydig cell line. Mice Leydig cells were cultured in the presence of different concentrations of bisphenols (0.04-50 µg.ml-1) during 24 h exposure. Quantification of the cell viability was assessed using the metabolic activity assay, while the level of testosterone in cell culture media was determined by enzyme-linked immunosorbent assay. Within the panel of substances under investigations, the higher experimental concentrations (10; 25 and 50 µg.ml-1) significantly (P<0.001) decreased Leydig cells viability, while the same doses of BPA and BPB also reduced testosterone production significantly (P<0.001). Taken together, the results of our study reported herein is a consistent whit the conclusion that higher experimental doses of bisphenols have a cytotoxic effect and could have a dose-dependent impact on testosterone production.

Meat and fat quality of Krskopolje pigs reared in conventional and organic production systems.

Data on production traits of the only Slovenian autochthonous pig breed, the Krskopolje pig, is very scarce. Krskopolje pigs are reared in conventional and organic production systems, which were compared in the present study. After weaning, 24 barrows were assigned within litter to either conventional (CON) or organic (ECO) rearing system. Group CON (n=12) was housed indoors in two pens (7.5 m2) with partly slatted floor. Group ECO (n=12) was held in a sty with sheltered area (concrete floor, bedded with straw, 16 m2) and outdoor paddock area (100 m2). The trial started when pigs had 68±8 kg BW and 157±6 days of age. Two diets were formulated with equivalent ingredients and composition. For ECO diet the ingredients used were ecological. Group ECO received a diet with 12.4 MJ metabolisable energy (ME) per kilogram and 12.9% CP and group CON a diet with 12.7 MJ ME/kg and 13.6% CP. Feed distribution was limited to 3.5 kg per pig daily. In line with the rules for organic production, ECO pigs were additionally given alfalfa hay ad libitum. After 73 days on trial, the pigs were slaughtered and carcass, meat and fat quality was evaluated. Meat quality traits (pH, colour, water holding capacity), fatty acid composition, lipid and protein oxidation, collagen content and solubility were analysed in longissimus lumborum (LL) muscle. Fatty acid composition, lipid oxidation, and vitamins A and E concentrations were determined in backfat. There were no significant differences in growth rate and carcass traits between ECO and CON pigs, however, ECO pigs tended (P<0.10) to have higher daily gain and lower dressing percentage, higher (P<0.001) pH 45 min and lower (P<0.01) pH 24 h postmortem, affecting (P<0.10) also water holding capacity and objective colour parameters (P<0.05) of LL muscle. There were no differences in intramuscular fat (IMF) content of LL muscle, however, IMF of ECO pigs had lower (P<0.05) proportion of saturated and higher (P<0.01) proportion of monounsaturated fatty acids accompanied by higher (P<0.001) values of thiobarbituric reactive substances (TBARS). In backfat, ECO pigs showed lower (P<0.05) vitamin E content, higher (P<0.001) TBARS, higher (P<0.01) degree of unsaturation (percentage of polyunsaturated fatty acids), and also higher (P<0.05) vitamin A concentration than CON pigs, which can be related to alfalfa hay supplementation of ECO pigs. In brief, organic rearing of Krskopolje pigs did not affect performances but had an effect on meat and fat quality.

Properties and aromatic profile of dry-fermented sausages produced from Krskopolje pigs reared under organic and conventional rearing regime.

Krskopolje pig, the only Slovenian autochtonous breed is still relatively untapped, with almost no information available on the effect of rearing conditions or its aptitude for processing and meat product quality. In the present study, dry-fermented sausages were produced from Krskopolje pigs that were fed similar diets (with regard to ingredients, energy and protein content) but reared in either conventional (CON) or organic conditions (ECO). Sausage weight losses at the end of processing were recorded and their final pH, chemical composition (moisture, fat and protein content, proteolysis index, fat and protein oxidation, fatty acid and free fatty acid profile) were determined in addition to measurements of instrumental texture, sensory evaluation and volatile profile analysis. Compared with CON, ECO dry-fermented sausages had lower processing losses, lower pH, higher moisture, salt and thiobarbituric acid reactive substances content, less saturated fat and less free fatty acids. Volatile profile analysis showed that ECO dry-fermented sausages exhibited higher concentrations of compounds arising from lipid autooxidation and lower levels of volatile compounds resulting from microbial lipid ß-oxidation, amino acid degradation and spices. Panellists perceived ECO dry-fermented sausages as saltier and less colour intensive, while both rheological and sensory analysis indicated that ECO sausages had softer texture than CON. The present results indicate that rearing of Krskopolje pigs according to organic standards induced differences in meat and fat properties which affected the quality of dry-fermented sausages, most distinctly in terms of softer texture and different volatile profile.

Protective Effects of Quercetin on Selected Oxidative Biomarkers in Bovine Spermatozoa Subjected to Ferrous Ascorbate.

Quercetin (QUE) is a natural flavonol-type flavonoid with antibacterial, anti-inflammatory and anti-aggregatory properties. It is also a powerful reactive oxygen species (ROS) scavenger and chelating agent. The aim of this study was to assess the effectiveness of QUE to reverse ROS-mediated alterations to the motility, viability and intracellular antioxidant profile of bovine spermatozoa. Spermatozoa were washed out of fresh bovine semen, suspended in 2.9% sodium citrate and subjected to QUE treatment (7.5, 25, 50 and 100 µmol/l) in the presence or absence of a pro-oxidant, that is ferrous ascorbate (FeAA; 150 µmol/l FeSO4 and 750 µmol/l ascorbic acid) during a 6-h in vitro culture. Spermatozoa motion characteristics were assessed using the SpermVision computer-aided sperm analysis (CASA) system. Cell viability was examined with the metabolic activity (MTT) assay, ROS generation was quantified via luminometry, and the nitroblue tetrazolium (NBT) test was applied to quantify the intracellular superoxide formation. Cell lysates were prepared at the end of the in vitro culture to investigate the intracellular activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) as well as the concentrations of glutathione (GSH) and malondialdehyde (MDA). FeAA treatment led to a reduced sperm motility (p < 0.001), viability (p < 0.001) and decreased the antioxidant parameters of the sperm samples (p < 0.001) but increased the ROS generation (p < 0.001), superoxide production (p < 0.001) and lipid peroxidation (p < 0.001). QUE administration resulted in a preservation of the spermatozoa vitality and antioxidant characteristics (p < 0.01 with respect to the enzymatic antioxidants, p < 0.001 in relation to GSH) with a concentration range of 50-100 µmol/l QUE revealing to be the most effective. Our results suggest that QUE exhibits significant ROS-scavenging and metal-chelating properties which may prevent spermatozoa alterations caused by ROS, and preserve the functionality of male reproductive cells.

Effect of high dietary fat content on heat production and lipid and protein deposition in growing immunocastrated male pigs.

In immunocastrated (IC) pigs, revaccination (V2) increases lipid deposition (LD) because of increased voluntary feed intake; but little is known on associated effect of diet composition on partitioning of nutrients in IC pigs. Digestibility measurements, N and energy balances in respiration chambers were performed in two subsequent stages in four replicates of two male littermates to determine the changes between 85 (stage 1) and 135 (stage 2) kg live weight due to combined effect of IC, growth and increased feed intake (IC/growth). During stage 1, pigs received a standard low-fat diet (LF diet; 2.5% dry matter (DM) of fat fed at 2.27 MJ metabolizable energy (ME)/kg BW0.60 per day), whereas during stage 2, feed intake was increased to 2.47 MJ ME/kg BW0.60 per day and one littermate was fed LF diet whereas the second received a fat-enriched diet (HF diet; 8.9% DM of fat) to determine the effect of increased dietary fat content on energy utilization in IC pigs. Results from N balance and measurements of gas exchanges were used to calculate respiratory quotient (RQ), heat production (HP), nutrient contribution to fat retention, components of HP, protein deposition (PD) and LD. Nutrients and energy apparent digestibility coefficients, methane losses and N retention (P<0.05) increased with IC/growth. Despite higher ME intake, total HP remained similar (1365 kJ/kg of BW0.60 per day; P=0.47) with IC/growth. Consequently, total retained energy (RE) increased with IC/growth (from 916 to 1078 kJ/kg of BW0.60 per day; P<0.01) with a higher fat retention (625 to 807 kJ/kg BW0.60 per day; P<0.01), originating mainly from carbohydrates associated with a higher lipogenesis (536 to 746 kJ/kg BW0.60 per day; P<0.01) and RQ (1.095 to 1.145; P<0.01). Both PD (from 178 to 217 g/day; P=0.02) and LD (from 227 to 384 g/day; P<0.01) increased due to IC/growth. Feeding HF diet after IC was associated with increased crude fat digestibility (P<0.01) and increased RE as fat (807 to 914 kJ/kg BW0.60 per day; P=0.03), originating mainly from dietary fat (P<0.01) and resulting in increased LD (384 to 435 g/day; P<0.01) and lower RQ (from 1.145 to 1.073; P<0.01). Altogether, present results indicate that increased fatness of IC pigs is a result of increased daily LD caused by higher energy intake and lower basal metabolic rate. In addition, LD is further enhanced by dietary energy enrichment with fat after V2.

The Impact of 4-Nonylphenol on the Viability and Hormone Production of Mouse Leydig Cells.

Exogenous substances altering the function of the endocrine system and exhibiting adverse health effects on the organism are defined as endocrine disruptors. Nonylphenol is one of the most abundant alkylphenol ethoxylate derivatives, being detected in food products. Diverse studies have classified nonylphenol as hazardous to the health, especially to male reproduction. This in vitro study aimed to examine the effects of 4-nonylphenol on androstenedione and testosterone production as well as on the viability of Leydig cells of NMRI mice. The cells were cultured for 44 h with addition of 0.04; 0.2; 1.0; 2.5 and 5.0 µg/ml of 4-nonylphenol and compared to the control. Quantification of testosterone and androstenedione directly from aliquots of the medium was performed by enzyme-linked immunosorbent assay. Cell viability was measured by the metabolic activity assay for mitochondrial functional activity. Androstenedione production significantly (P < 0.001) increased with 1.0; 2.5 and 5.0 µg/ml 4-nonylphenol. Although cAMP-stimulated testosterone production was not significantly affected by 4-nonylphenol, a tendency to attenuate the level of testosterone in the Leydig cells treated with 2.5 and 5.0 µg/ml 4-nonylphenol was observed. The viability of mouse Leydig cells was slightly increased at the lowest doses of 4-nonylphenol (0.04 and 0.2 µg/ml). We also observed an increase at higher concentrations of the substance (1.0; 2.5 and 5.0 µg/ml), but this increase was not significant. Further investigations are required to establish the biological significance and possible reproductive implications.

Hydrolysable tannin fed to entire male pigs affects intestinal production, tissue deposition and hepatic clearance of skatole.

The effect of adding hydrolysable tannins to the diet of fattening boars was studied. Performance, reproductive organ weights, salivary gland morphology, boar taint compounds and skatole metabolism were evaluated. At 123 days of age and 52 ± 6 kg liveweight, 24 Landrace × Large White boars were assigned within a litter to four treatment groups: control (T0 fed mixture with 13.2 MJ/kg, 17.5% crude proteins) and three experimental diets for which the T0 diet was supplemented with 1%, 2% and 3% of hydrolysable tannin-rich extract (T1, T2 and T3, respectively). Pigs were kept individually with ad libitum access to feed and water and slaughtered at 193 days of age and 122 ± 10 kg liveweight. Adding hydrolysable tannins to the diet had no negative effect on growth performance at 1% and 2%, whereas the 3% inclusion reduced feed intake and resulted in an adaptive response of the salivary glands (particularly parotid gland hypertrophy). Relative to T0, fat tissue skatole concentration was increased in the T1 group, but was similar in T2 and T3. Across treatments tissue skatole concentrations were proportional to the activity of hepatic CYP450. The results indicate the potential of tannin supplementation to reduce boar taint although further investigations are needed in order to establishing optimal dosage.

The effect of transgenesis on rabbit thyroid tissue structure.

This study was aimed to compare structures of the thyroid tissue of transgenic rabbits expressing the human clotting factor VIII under the murine whey acidic protein promoter (mWAP-hFVIII rabbits) with the non-transgenic controls. Thyroid tissue samples were taken from transgenic and non-transgenic New Zealand White rabbits, examined by optical microscopy and analysed morphometrically. The analysis revealed no significant differences (P > 0.05) in the relative volume of basic thyroid structures. Furthermore, no significant differences (P > 0.05) were observed when measuring the epithelial height and nuclear diameter of the follicular cells. Altogether, this study demonstrates no negative effect of the mWAP-hFVIII transgenesis on the rabbit thyroid gland structure.

Characteristics of rabbit transgenic mammary gland expressing recombinant human factor VIII.

The objective of this research was to compare (i) the content of milk protein and recombinant human factor VIII (rhFVIII) in the milk of transgenic and non-transgenic rabbit females at three lactations and (ii) histological structure, ultrastructural morphology and occurrence of apoptosis in rabbit transgenic and non-transgenic mammary gland during third lactation and involution. Significant differences (t(0.05)) in milk protein content were found between transgenic and non-transgenic at all three lactations. The percentage of apoptotic cells was significantly higher (t(0.01)) in non-transgenic ones compared with transgenic mammary gland tissues (6.5% versus 2.4%) taken at the involution stage. Morphometrical analysis of histological preparations at the involution stage detected a significantly higher (t(0.05)) relative volume of lumen in transgenic animals compared with non-transgenic ones (60.00 versus 46.51%). Ultrastructural morphology of the transgenic mammary gland epithelium at the involution stage revealed an increased relative volume of protein globules (t(0.05)); at the lactation stage, a significantly higher volume of mitochondria (13.8%) compared with the non-transgenic (9.8%) ones was observed. These results, although revealing differences in some parameters of ultrastructure and histology, indicate no harmful effect of the mouse whey acid protein-hFVIII transgene expression on the state of mammary gland of transgenic rabbit females.

Female reproductive toxicology of cadmium.

The aim of this study was to determine effects of Cd on the structure of ovary, oviduct and uterus after an experimental administration. Animals were divided into three groups. In group A rabbits received cadmium i.p. and were killed after 48 h. In group C Cd was administered p.o. for 5 month. The group K was the control. Decreased relative volume of growing follicles and increased stroma after Cd administration were detected. The number of atretic follicles was significantly higher after administration of Cd. The most frequent ultrastructural alterations observed were undulation of external nuclear membrane, dilatation of perinuclear cistern and endoplasmic reticulum. In all studied types of cells mitochondria with altered structure were found. In the oviduct the highest amount of epithelium in the group with long-term Cd administration was found. Microscopic analysis showed oedematization of the oviduct tissue, caused by disintegration of the capillary wall. An electron microscopic analysis showed dilatation of perinuclear cistern. The intercellular spaces were enlarged and junctions between cells were affected. Mainly after a long-term cadmium administration nuclear chromatin disintegration was present. In the uterus a significant change was determined in the relative volume of glandular epithelium. Increase of stroma was a sign of uterus oedamatization caused by damage in the wall of blood vessels and subsequent diapedesis. After Cd administration alteration in uterus were less expressed, in comparison with ovary and oviduct. Alteration of nuclear chromatin contain following Cd administration suggests degenerative functional changes.

Nickel seminal concentrations in various animals and correlation to spermatozoa quality.

In this study, the concentration of nickel in stallion, bull, ram, boar and fox semen, and its relation with spermatozoa quality was analyzed. The concentration of nickel in semen was 0.20 mg kg(-1) in stallion, 0.12 mg kg(-1) in bull, 0.31 mg kg(-1) in ram, 0.06 mg kg(-1) in boar and 0.36 mg kg(-1) in fox. Seminal nickel concentration was significantly higher (P < 0.05) in foxes than that in bulls and significantly higher (P < 0.01) in rams and foxes in comparison with boars. Evaluation of total pathological spermatozoa revealed the highest number in stallions followed by rams, bulls, boars and foxes. In bull, ram and boar semen, separated flagellum, flagellum torso and knob-twisted flagellum were predominant. Knob-twisted flagellum, separated flagellum and flagellum torso were found in increased number in stallion semen and broken flagellum in fox semen. Correlation analysis in bulls indicated a high positive correlation between seminal nickel and separated flagellum (r = 0.76) and medium positive correlation between nickel and flagellum torso (r = 0.62), and in rams a high positive correlation between nickel and separated flagellum (r = 0.77). Medium positive correlation was found between nickel and separated flagellum (r = 0.43) and between nickel and other pathological spermatozoa (r = 0.45) in boars.

[Effects of trace elements on the immune system]. / Vplyv stopoýtch prvkov na imunitný systém.

Trace elements as essential micronutrients play an important role in various physiological processes and are crucial for proper functioning of the immune system. Deficiency of trace elements and infectious diseases are often concomitantly observed and result in complex interactions. The major trace elements such as selenium, zinc, copper, manganese, etc. have immunomodulatory effects and thus influence susceptibility to and the course and outcome of a variety of viral infections. Some trace elements inhibit viral replication in the host cells and therefore have antiviral activity. Many trace elements act as antioxidants or are able not only to regulate the host immune response but also to alter the viral genome. This article gives a brief review of the major interactions between the trace elements and the immune system.