Silymarin protects plasma membrane and acrosome integrity in sperm treated with sodium arsenite

Background: Exposure to arsenic is associated with impairment of male reproductive function by inducing oxidative stress. Silymarin with an antioxidant property scavenges free radicals

Objective: The aim of this study was to investigate if silymarin can prevent the adverse effects of sodium arsenite on ram sperm plasma membrane and acrosome integrity

Materials and Methods: Ram epidydimal spermatozoa were divided into five groups: spermatozoa at 0 hr, spermatozoa at 180 min [control], spermatozoa treated with silymarin [20 micro M] + sodium arsenite [10 micro M] for 180 min, spermatozoa treated with sodium arsenite [10 micro M] for 180 min and spermatozoa treated with silymarin [20 micro M] for 180 min. Double staining of Hoechst and propidium iodide was performed to evaluate sperm plasma membrane integrity, whereas comassie brilliant blue staining was used to assess acrosome integrity

Results: Plasma membrane [p< 0.001] and acrosome integrity [p< 0.05] of the spermatozoa were significantly reduced in sodium arsenite group compared to the control. In silymarin + sodium arsenite group, silymarin was able to significantly [p< 0.001] ameliorate the adverse effects of sodium arsenite on these sperm parameters compared to sodium arsenite group. The incubation of sperm for 180 min [control group] showed a significant [p< 0.001] decrease in acrosome integrity compared to the spermatozoa at 0 hour. The application of silymarin alone for 180 min could also significantly [p< 0.05] increase sperm acrosome integrity compared to the control

Conclusion: Silymarin as a potent antioxidant could compensate the adverse effects of sodium arsenite on the ram sperm plasma membrane and acrosome integrity

Protective effect of silymarin on viability, motility and mitochondrial membrane potential of ram sperm treated with sodium arsenite

Background: Sodium arsenite can impair male reproductive function by inducing oxidative stress. Silymarin is known as a potent antioxidant

Objective: This study was performed to investigate if silymarin can prevent the adverse effect of sodium arsenite on ram sperm viability, motility and mitochondrial membrane potential

Materials and Methods: Epidydimal spermatozoa obtained from ram were divided into five groups: 1] Spermatozoa at 0 hr, 2] spermatozoa at 180 min [control], 3] spermatozoa treated with sodium arsenite [10 microM] for 180 min, 4] spermatozoa treated with silymarin [20 microM] + sodium arsenite [10 microM] for 180 min and 5] spermatozoa treated with silymarin [20 microM] for 180 min. MTT assay and Rhodamine 123 staining were used to assess sperm viability and mitochondrial membrane potential respectively. Sperm motility was performed according to World Health Organization [WHO] guidelines

Results: Viability [p<0.01], nonprogressive motility [p<0.001] and intact mitochondrial membrane potential [p<0.001] of the spermatozoa were significantly decreased in sodium arsenite treated group compared to control group. In silymarin + sodium arsenite group, silymarin could significantly reverse the adverse effect of sodium arsenite on these sperm parameters compared to sodium arsenite group [p<0.001]. In addition, the application of silymarin alone for 180 minutes could significantly increase progressively motile sperm [p<0.001] and decrease non motile sperm [p<0.01] compared to the control

Conclusion: Silymarin could compensate the adverse effect of sodium arsenite on viability, nonprogressive motility and mitochondrial membrane potential of ram sperm

Curcumin inhibits the adverse effects of sodium arsenite in mouse epididymal sperm

Background: The aim of this study was to investigate the effects of curcumin on epididymal sperm parameters in adult male Navel Medical Research Institute [NMRI] mice exposed to sodium arsenite

Materials and Methods: In this experimental study, we divided the animals into four groups: control, sodium arsenite [5 mg/kg], curcumin [100 mg/kg] and curcumin+sodium arsenite. Exposures were performed by intraperitoneal injections for a 5-week period. After the exposure period, we recorded the animals' body and left testes weights. The left caudal epididymis was used to count the sperm number and analyze motility, viability, morphological abnormalities, acrosome reaction, DNA integrity, and histone-protamine replacement in the spermatozoa. Oneway analysis of variance [ANOVA] followed by the Tukey's test was used to assess the statistical significance of the data with SPSS 16.0. P<0.05 was considered significant

Results: Mice exposed to sodium arsenite showed a significant decrease in the number, motility, viability, normal sperm morphology and acrosome integrity of spermatozoa compared to the control group. In the curcumin+sodium arsenite group, curcumin significantly reversed these adverse effects to the point where they approximated the control. In addition, the application of curcumin alone had no significant difference in these parameters compared to the control and curcumin+sodium arsenite groups. However, we observed no significant differences in the body and the testis weight as well as the DNA integrity and histone-protamine replacement in the spermatozoa of the four groups

Conclusion: Curcumin compensated for the toxic effects of sodium arsenite on a number of sperm parameters in adult mice

Caspase-mediated apoptosis in sensory neurons of cultured dorsal root ganglia in adult mouse

Sensory neurons in dorsal root ganglia [DRG] undergo apoptosis after peripheral nerve injury. The aim of this study was to investigate sensory neuron death and the mechanism involved in the death of these neurons in cultured DRG. In this experimental study, L5 DRG from adult mouse were dissected and incubated in culture medium for 24, 48, 72 and 96 hours. Freshly dissected and cultured DRG were then fixed and sectioned using a cryostat. Morphological and biochemical features of apoptosis were investigated using fluorescent staining [Propidium iodide and Hoechst 33342] and the terminal Deoxynucleotide transferase dUTP nick end labeling [TUNEL] method respectively. To study the role of caspases, general caspase inhibitor [Z-VAD.fmk, 100 microM] and immunohistochemistry for activated caspase-3 were used. After 24, 48, 72 and 96 hours in culture, sensory neurons not only displayed morphological features of apoptosis but also they appeared TUNEL positive. The application of Z-VAD.fmk inhibited apoptosis in these neurons over the same time period. In addition, intense activated caspase-3 immunoreactivity was found both in the cytoplasm and the nuclei of these neurons after 24 and 48 hours. Results of the present study show caspase-dependent apoptosis in the sensory neurons of cultured DRG from adult mouse

Effects of a voltage sensitive calcium channel blocker and a sodium-calcium exchanger inhibitor on apoptosis of motor neurons in adult spinal cord slices

The apoptosis of motor neurons is a critical phenomenon in spinal cord injuries. Adult spinal cord slices were used to investigate whether voltage sensitive calcium channels and Na[+]/Ca[2+] exchangers play a role in the apoptosis of motor neurons. In this experimental research, the thoracic region of the adult mouse spinal cord was sliced using a tissue chopper and the slices were incubated in a culture medium in the presence or absence of N/L type voltage sensitive calcium channels blocker [loperamide, 100 micro M] or Na[+]/Ca[2+] exchangers inhibitor[bepridil, 20 micro M] for 6 hours. 3-[4, 5-dimethylthiazol-2-yl]-2, 5 diphenyl tetrazolium [MTT] staining was used to assess slice viability while morphological features of apoptosis in motor neurons were studied using fluorescent staining. After 6 hours in culture, loperamide and bepridil not only increased slice viability, but also prevented motor neuron apoptosis and significantly increased the percentage of viable motor neurons in the ventral horns of the spinal cord. The results of this study suggest that voltage sensitive calcium channels and Na[+]/Ca[2+] exchanger might be involved in the apoptosis of motor neurons in adult spinal cord slices

Effect of vitamin E on sperm parameters and DNA integrity in sodium arsenite-treated rats

Arsenic as an environmental toxicant is able to exert malformations in male reproductive system by inducing oxidative stress. Vitamin E [Vit.E] is known as antioxidant vitamin. The aim of this study was to investigate the harmful effects of sodium arsenite on sperm parameters and the antioxidant effects of Vit.E on sperm anomalies in sodium arsenite treated rats. Adult male rats were divided into 4 groups: control, sodium arsenite [8 mg/kg/day], Vit.E [100 mg/kg/day] and sodium arsenite+Vit.E. Oral treatments were performed till 8 weeks. Body and left testis weight were recorded and then left caudal epididymis was cut in Ham's F10. Released spermatozoa were used to analyze number, motility, viability and abnormalities of the sperm. Sperm chromatin quality was assessed by nuclear staining using acridine orange and aniline blue. Body and testis weight showed no significant change in 4 groups [p>0.05]. A significant decrease in the number, motility, viability and normal sperm morphology was found in sodium arsenite-treated rats compared to the control [p<0.001]. Sodium arsenite had no effect on sperm DNA integrity and histon-protamine replacement [p>0.05]. In sodium arsenite+Vit.E group, Vit.E could significantly compensate the harmful effects of sodium arsenite on sperm number, motility, viability and morphology compared to sodium arsenite group. In addition, sperm viability and motility was significantly increased in rats treated with Vit.E alone compared to the control and sodium arsenite+Vit.E group. Vitamin E could compensate the adverse effects of sodium arsenite on sperm parameters in adult rats

Role of calpain in apoptosis

Apoptosis, a form of programmed cell death that occurs under physiological as well as pathological conditions, is characterized by morphological and biochemical features. While the importance of caspases in apoptosis is established, several noncaspase proteases [Ca2+-dependent proteases] such as calpain may play a role in the execution of apoptosis. The calpain family consists of two major isoforms, calpain I and calpain II which require micro M and mM Ca2+ concentrations to initiate their activity. An increase in intracellular Ca2+ level is thought to trigger a cascade of biochemical processes including calpain activation. Once activated, calpains degrade membrane, cytoplasmic and nuclear substrates, leading to the breakdown of cellular architecture and finally apoptosis. The activation of calpain has been implicated in neuronal apoptosis following spinal cord injuries and neurodegenerative diseases. This review focuses on calpain with an emphasis on its key role in the proteolysis of cellular protein substrates following apoptosis

[Effect of the polyamine component, TDMTN, on apoptosis of motor neurons in adult mouse spinal cord slices]

The aim of this study was to investigate the preventive effect of the polyamine component N, N, N, N-tetrakis[2-aminoethyl]2,2-dimethylpropane-1,3-diamine [tdmtn] on apoptotic motor neurons in adult mouse spinal cord slices. Thoracic region of adult mouse spinal cords was sliced by a tissue chopper into 400 micro m slices and cultured in medium in the presence or absence of tdmtn for 6 hours. Morphological a features of apoptosis were evaluated using fluorescent staining with propidium iodide and Hoechst 33342. The appearance of nucleosomal DNA fragmentation was studied using agarose gel electrophoresis. Our results were analyzed using the one-way ANOVA and Tukey's tests. After 6 hours in culture, motor neurons displayed morphological sings of apoptosis including cell shrinkage, as well as nuclear and chromatin condensation. DNA extracted from slices cultured for 24 hours revealed nucleosomal DNA fragmentation on agarose gel electrophoresis. Tdmtn reduced the occurrence of apoptosis in motor neurons and significantly [p<0.01] increased the viability of these neurons after 6 hours of culturing. Tdmtn, as a polyamine component, could probably prevent the occurrence of motor neuron apoptosis through calcium chelation

Effects of vitamin E on ovarian tissue of rats following treatment with p-nonylphenol: a stereological study

Para-Nonylphenol [p-NP] is one of the environmental pollutants which cause reproductive system disorders. The effects of vitamin E on ovary structure during its development in rats treated with p-NP. 32 Wistar female rats after mating were divided into 4 groups; control, vitamin E [100mg/kg/day], p-NP [250mg/kg/day] and p-NP + vitamin E. The rats were treated from the day 7 of pregnancy till 21st day of postnatal through sucking period. After weaning, the female pups were treated by gavages for 120 days. The total volume of ovary, number of follicles, volume of oocyte, follicular cells and their nuclei and the thickness of zona pellucida were estimated stereologically. The results were analyzed using one way ANOVA and p<0.05 was considered significant. The ovary weight, mean total volume of ovary and cortex, number of antral and graafian follicles and body weight were decreased significantly [p<0.05] in the p-NP treated rats compared to control and other groups, while the number of atretic follicles was increased significantly [p<0.05]. A significant reduction [p<0.05] in volume of oocyte, follicular cells and their nuclei in antral and graafian follicles was found in p-NP group. In addition, treatment with only vitamin E showed an improving effect on folliculogenesis due to a highly significant increase [p<0.01] in the number of primordial follicles. Vitamin E could compensate the adverse effects of p-NP on the ovary structure during its development