Jaroslav Kovacik

Distribution of cadmium and lead in liver and kidney of some wild animals in Slovakia

Abstract The content of cadmium and lead, as risk factors of environment, in liver and kidneys of wild animals as brown hare (Lepus europaeus), yellow-necked mouse (Apodemus flavicollis), wood mouse (Cleithrionomys glareolus), and red deer (Cervus elaphus) were studied. Samples were analyzed by the atomic absorption spectrophotometry method (AAS). The highest levels of cadmium were found in kidneys (0.213–2.387 mg/kg) of all animal species. The concentration of cadmium in liver was 0.032–0.258 mg/kg. The analysis of lead showed that the concentration of this element was higher in kidneys of yellow-necked mouse and wood mouse (0.503–0.780 mg/kg) than in liver (0.177–0.268 mg/kg). In brown hare and red deer a higher accumulation of lead in liver (0.221–1.904 mg/kg) in comparison with kidneys (0.115–0.561 mg/kg) is reported.

Environmental levels of cadmium, lead and mercury in brown hares and their relation to blood metabolic parameters.

The purpose of this study was to examine concentrations of selected heavy metals in the liver and kidney of brown hares (Lepus europaeus). In addition, correlations between heavy metals and biochemical parameters in blood plasma were determined. The average concentrations of heavy metals (mmol/L) ± SD were as follows: liver: Pb 0.221 ± 0.189, Cd 0.160 ± 0.140, Hg 0.021 ± 0.030, kidney: Pb 0.115 ± 0.125, Cd 1.570 ± 1.103, Hg 0.030 ± 0.053. The average concentrations of biochemical parameters in the blood plasma were as follows: Ca 3.16 mmol/L, P 2.19 mmol/L, Mg 1.40 mmol/L, Na 148.71 mmol/L, K 8.12 mmol/L, glucose 6.56 mmol/L, total proteins 56.49 g/L, urea 5.00 mmol/L, total lipids 1.40 g/L, bilirubin 3.97 μ mol/L, cholesterol 1.53 mmol/L, aspartate aminotransferase (AST) 6.06 μ kat/L and alanine aminotransferase (ALT) 1.94 μ kat/L. Average levels of hormones (ng/mL) were as follows: testosterone 2.94, androstendiol 0.13, estradiol 501.59, progesterone 6.63, oxytocin 328.60. Tissue analysis showed an accumulation of lead, cadmium and mercury in the liver and kidney of brown hares. There were no significant correlations between levels of heavy metals in liver, kidney, and biochemical parameters.

Mercury-induced alterations in rat kidneys and testes in vivo

In this study effects of mercury administration on the kidney and testicular structure of adult rats were evaluated. Rats received mercury (HgCl2) in single intraperitoneal dose 20 mg HgCl2 (group A), 10 mg HgCl2 (group B) and 5 mg HgCl2 (group C) per kilogram of body weight and were killed after 48 hours following mercury administration. After the preparation of histological samples the results were compared with control group (K). In kidney decreased diameters of glomeruli and renal corpuscles, damaged tubules with affected quality of tubular cells and infiltration of interstitium were detected. Quantitative analysis demonstrated increased relative volume of tubules and renal corpuscles. Also the number of nuclei and glomeruli was increased in all experimental groups. The diameter of glomeruli and renal corpuscles was decreased. In testis undulation of basal membrane, dilatation of blood vessels in interstitium and occurrence of empty spaces in germinal epithelium were observed. Decreased relative volume of germinal epithelium, increased relative volume of interstitium and increased apoptosis occurrence suggest damaged interstitium and revealed occurrence of edemas. The relative volume of seminiferous tubules showed higher luminization. The number of nuclei was decreased in all experimental groups what is in positive relation with occurrence of empty spaces. Also other evaluated criteria demonstrated significant differences between control group and experimental groups. This study reports a negative effect of mercury on the structure and function of kidney and testes.

The effect of deoxynivalenol on the secretion activity, proliferation and apoptosis of porcine ovarian granulosa cells in vitro

The aim of this in vitro study was to examine the secretion activity, markers of proliferation and apoptosis in porcine ovarian granulosa cells (GCs) after deoxynivalenol (DON) addition. Ovarian granulosa cells were incubated with DON for 24h: 10, 100 and 1000 ng/mL, while the control group received no DON. The secretion of insulin-like growth factor I (IGF–I) and progesterone was determined by radioimmunoassay (RIA) and expression of cyclin B1, PCNA and caspase-3 by immunocytochemistry. IGF–I release by GCs was inhibited by DON, while progesterone release and the expression of cyclin B1 was stimulated by DON (at 1000 ng/mL but not at 10 and 100 ng/mL). PCNA expression was stimulated by DON (at 100 and 1000 ng/mL but not at 10 ng/mL). Caspase-3 expression was not influenced by DON treatment (at all doses). In conclusion, our results indicate, (1) a direct effect of DON on secretion of growth factor IGF-I and steroid hormone progesterone, (2) expression of markers of proliferation (cyclin B1 and PCNA) but not on the (3) expression of marker of apoptosis (caspase-3) in porcine ovarian granulosa cells. This in vitro study suggests the dose-dependent association of DON on porcine ovarian functions.

Nickel induced alteration of hen body weight, egg production and egg quality after an experimental peroral administration.

In this study the effects of nickel (NiCl2) administered in drinking water (0.02; 0.2 and 2.0 mg NiCl2/L for 28 days) on laying hen body weight, egg production and egg quality is reported. Growth parameters during the experiment were significantly decreased mainly in the group with the highest nickel concentration. In total egg production dose–dependent decrease in all experimental groups was found. Egg weight was mainly affected in the group with the highest nickel concentration. Specific egg weight was not altered. Albumen weight and albumen content was significantly decreased in groups with the highest nickel concentration in comparison with the control group. Egg yolk analysis detected significantly decreased yolk weight in the group with the highest nickel experimental level. In yolk color a significant difference was detected between the group receiving 0.02 and 0.2 mg NiCl2/mL. Eggshell compactness was increased in all experimental groups what could be induced by altered mineralization of eggshell. Results of this study clearly report a negative effect of nickel as an environmental pollutant on laying hen body weight, egg production as well as egg quality.

Cobalt-induced changes in the IGF-I and progesterone release, expression of proliferation- and apoptosis-related peptides in porcine ovarian granulosa cells in vitro

Cobalt (Co) is an essential element. The general objective of this in vitro study was to examine dose-dependent changes in the secretory activity of porcine ovarian granulosa cells after experimental Co administration and to outline the potential intracellular mediators of its effects. Concentrations of IGF-I and progesterone were determined by RIA and expression of cyclin B1 and caspase-3 by immunocytochemistry. IGF-I release by granulosa cells was stopped by Co addition at the concentration 1 mg/mL. Progesterone release by granulosa cells was decreased at the lowest Co addition (0.09 mg/mL). In our study the changes of the expression of proliferation related peptide cyclin B1 and apoptosis related peptide caspase-3 in ovarian granulosa cells was observed after experimental Co addition. The molecular pathways stimulated by Co through the expression of cyclin B1 and caspase-3 were found. In conclusion, this study provides novel evidence that cobalt is the factor which can initiate adverse effects in ovarian granulosa cells. These results contribute towards the understanding of mechanisms relating to endocrine disruptor-induced alterations in porcine ovarian granulosa cells.

Nickel-induced blood biochemistry alterations in hens after an experimental peroral administration.

The purpose of this study was to determine certain blood biochemical parameters in hens of Isa Brown breed (n = 20) after nickel administration. Animals were divided into four groups (K, P1, P2, P3). Experimental hens (n = 5; in each group) received nickel (NiCl2) as peroral administration in drinking water in various doses (P1 – 0.02 g NiCl2/L; P2 – 0.2 g NiCl2/L; P3 – 2.0 g NiCl2/L of drinking water) for 28 days. The last group – K (n = 5) was the control, receiving no nickel. Biochemical parameters of mineral profile (calcium; phosphorus; magnesium; sodium; potassium) and of energy and enzymatic profile [(glucose; total cholesterol; total proteins; triglycerides; alanine aminotransferase (ALT) aspartate aminotransferase (AST) gamma glutamyl transferase (GGT) and glutamatdehydrogenase (GLDH)] were analyzed in blood serum on Day 0, 7, 14, 21 and 28 of the experiment. Average levels of mineral metabolism parameters were relatively stable apart from calcium. The evaluation registered a significant decrease in calcium during the experiment mainly in the group with highest nickel concentration in drinking water. No significant differences were detected between groups in energy and enzymatic profile apart from the concentrations of ALT on Day 7. In conclusion, there were significant associations between nickel levels and calcium and ALT in blood serum of the hens. No significant differences were detected in other biochemical parameters of mineral profile (P, Mg, Na, K) and energy and enzymatic profile (glucose, total cholesterol, total proteins, triglycerides, AST, GGT and GLDH) after nickel administration. Our results may contribute to an evaluation of reference levels of analyzed parameters, to monitor the health and nutritional status of hens. In this study also the negative effect of nickel mainly on calcium metabolism was detected.

In vitro assessment of molybdenum-induced secretory activity, proliferation and apoptosis of porcine ovarian granulosa cells.

Molybdenum (Mo) is an essential trace element and it plays an important role in cell functions. The mechanism of the action of molybdenum in connection with growth factor IGF–I, proliferation-related peptide cyclin B1 and apoptosis-related peptide caspase-3 has not been examined previously in porcine ovarian granulosa cells. The general objective of this in vitro study was to examine the secretory activity of porcine ovarian granulosa cells after experimental Mo administration and to outline the potential intracellular mediators of its effects. Ovarian granulosa cells were incubated with ammonium molybdate for 18 hours: 1.0 mg/mL; 0.5 mg/mL; 0.33 mg/mL; 0.17 mg/mL and 0.09 mg/mL, while the control group received no Mo. The secretion of IGF-I was assessed by RIA and expression of cyclin B1 and caspase-3 by immunocytochemistry. IGF–I release was decreased by Mo addition at the doses 1.0 mg/mL and 0.5 mg/mL. The expression of cyclin B1 was stimulated by Mo addition at all doses ranging from 1.0 – 0.09 mg/mL. Caspase–3 expression was also stimulated after experimental Mo addition at the doses 1.0 and 0.5 mg/mL. These data contribute to new insights regarding the mechanism of action of Mo on porcine ovarian functions, secretory activity, proliferation and apoptosis of granulosa cells through hormonal and intracellular substances such as are cyclin B1 and caspase–3.

In vitro assessment of silver effect on porcine ovarian granulosa cells

The general objective of this in vitro study was to examine the secretory activity (insulin-like growth factor I, IGF-I) of porcine ovarian granulosa cells after Ag addition and to outline the potential intracellular mediators (cyclin B1 and caspase-3) of its effects. Ovarian granulosa cells were incubated with silver nitrate (AgNO(3)) at the doses 0.09, 0.17, 0.33, 0.5 and 1.0 mg/mL for 18 h and compared to the control group without metal addition. The release of IGF-I by granulosa cells was assessed by RIA and expression of cyclin B1 and caspase-3 immunocytochemistry. Our observations show that IGF-I release by granulosa cells was significantly (P<0.05) stimulated by AgNO(3) addition at the doses (0.09-1.0 mg/mL). Similarly to IGF-I the cyclin B1 and caspase-3 expression in ovarian granulosa cells was stimulated by Ag addition (0.09-1.0 mg/mL). In conclusion, the present results indicate, a direct effect of Ag on (1) secretion of growth factor IGF-I, (2) expression of markers of proliferation (cyclin B1) and apoptosis (caspase-3) of porcine ovarian granulosa cells and (3) that the effect of Ag on ovarian cell proliferation could be mediated by IGF-I and cyclin B1. Obtained data indicate the interference of Ag in the pathways of proliferation and apoptosis of porcine ovarian granulosa cells through hormonal and intracellular peptides such as are cyclin B1 and caspase-3.

Blood concentration of copper, cadmium, zinc and lead in horses and its relation to hematological and biochemical parameters

Environmental pollution results in serious health hazards to animals and blood analysis serves as a good alternative for health status assessment. The target of this study was to analyze the concentration of selected metals in equine blood, to analyze the blood parameters and to find possible correlations. Blood samples were collected from the vena jugularis of healthy adult horses. The highest concentration of all elements was found in whole blood (Cu 3.84 ± 0.90 mg L−1; Cd = 0.81 ± 0.90 mg L−1; Zn 26.67 ± 14.12 mg L−1; Pb 9.33 ± 5.76 mg L−1). Higher concentrations of copper, cadmium, zinc and lead were detected in blood clots compared to blood sera (44.04%). A similar tendency was found for cadmium (50%), zinc (13.08%) and lead (46.02%), which showed generally higher concentrations in blood clots (cells). Correlation analysis proved some relations between analyzed elements. In blood clots there is a strong positive correlation between Cd – Pb (r = 0.93) and Zn – Pb (r = 0.71) was detected. For biochemical and hematological parameters mainly medium correlations were detected. Obtained results prove different correlations of analyzed elements in blood components as well as the effect on parameters of blood biochemical and hematological profiles.