Correlation between lead and cadmium concentration and semen quality

There are contrary reports of association of lead and cadmium with the decline in semen quality. This study evaluates whether seminal lead (Pb) and cadmium (Cd) at environmental concentration are associated with altered semen quality. We conducted a study of healthy fertile and infertile men 20-43 years of age attending the Andrology Laboratory of Reproductive Biology Department for semen analysis. The semen analysis was carried out according to the WHO 2010 guidelines. Seminal lead and cadmium were estimated by ICP-AES. The lead and cadmium values were significantly higher in infertile subjects. A negative association between seminal lead or cadmium concentration and sperm concentration, sperm motility and per cent abnormal spermatozoa was found. This study shows that exposure to Pb (5.29-7.25 μg dl(-1) ) and cadmium (4.07-5.92 μg dl(-1) ) might affect semen profile in men. Age, diet, smoking and tobacco chewing habits may have an influence on the increase in exposure to Pb and Cd in the individual subjects.

Environmental and experimental exposure of phthalate esters: The toxicological consequence on human sperm

Rapid industrialization and urbanization release several chemicals such as phthalates into the environment and cause adverse effects on reproductive system, mainly endocrine disruption, testicular injury and decline in semen quality in humans. There are no reports in extrapolating of the epidemiological data with in vitro findings. Our study show the correlations between in vivo studies and in vitro data for the effect of phthalate esters. Healthy human males, in the age group 21 to 40 years, visiting Chhatrapati Sahuji Maharaj Medical University (CSMMU), Lucknow, as part of infertility investigation, were recruited as volunteers. Semen analysis was performed according to the WHO guidelines. Phthalate esters were analyzed by high-performance liquid chromatography (HPLC) and cell viability by MTT assay. In the in vitro studies, sperms were exposed to highest concentration in semen samples (5—10 times higher) for a period ranging between 30 min and 96 hours. An inverse relationship with sperm motility in epidemiological studies was concurrent by significant dose-and time-dependent decrease in the sperm motility under in vitro environment after 12-hour exposure. Cytotoxicity was observed only with the highest concentration after 96 hours of exposure. There are a significant correlation between phthalate ester diethylhexyl phthalate, di-n-butyl phthalate (DEHP and DBP) and sperm motility both in vitro and in vivo conditions. Additionally, in vitro experiments conducted not only adjunct to the existing in vivo data but also specify the effect of specific toxicants (DEHP and DBP) on sperm motility and viability. Results show the decrease in motility of sperms under in vitro conditions at the maximum range of in vivo measured levels and 5- or 10-folds higher to that found in human semen samples.

Convenient Direct Synthesis of Bisformylated Calix[4]arenes viaIpsoSubstitution

[reaction: see text] A facile synthesis of bisformylated calix[4]arenes via ipso substitution of p-tert-butylcalix[4]arenes through treatment with hexamethylenetetramine/trifluoroacetic acid is described. Under identical conditions, p-tert-butylcalix[4]arene tetramethyl ether 4 gives proximally substituted bisformylated derivative 4a in a pinched cone conformation.

Reduction in morbidity of rotavirus induced diarrhoea in mice by yeast produced monovalent llama-derived antibody fragments

Apart from the use of oral rehydration solution, there are currently no treatment modalities for rotavirus induced diarrhoea, which is particularly relevant to developing countries. Fragments derived from llama heavy chain antibodies were previously shown to be highly stable, efficiently produced in yeast and exhibiting high epitope specific affinity. We now aim to demonstrate that these antibody fragments are capable of reducing morbidity of rotavirus induced diarrhoea. Here we show the isolation of rotavirus specific antibody fragments and their capability of reducing the morbidity of rotavirus induced diarrhoea in vivo in mice. They could provide a treatment modality for the moderation of human rotavirus infections having a significant impact on the course of an often fatal childhood disease.

Testicular and spermatotoxic effects of quinalphos in rats

Testicular and spermatotoxic effects were investigated in rats exposed to technical-grade quinalphos (70%) at dose levels of 0.52 mg kg(-1) (1/50th ld(50)) or 1.04 mg kg(-1) body weight (1/25th ld(50)) for 5 days a week for 60 days. The activities of marker testicular enzymes such as sorbitol dehydrogenase (SDH) and acid phosphatase were significantly decreased but those of lactate dehydrogenase (LDH), gamma-glutamyl transpeptidase (gamma-GT) and beta-glucuronidase were significantly increased in a dose-dependent manner. This particular pattern in the activity of testicular-cell-specific enzymes, a decrease in sperm motility and total epididymal sperm count and an increase in abnormal sperm suggest damage to germ cells and Sertoli cells. The testicular and spermatotoxic effects observed in rats may be due to the pesticide quinalphos or its metabolites.

Correlation of lead and cadmium in human seminal plasma with seminal vesicle and prostatic markers

The objective of this study was to investigate the correlation between lead and cadmium with seminal vesicle and prostatic markers. Semen samples categorized into fertile and infertile were evaluated for the presence of lead and cadmium and biochemical markers in the seminal plasma. Associations between lead and fructose, acid phosphatase and gamma-glutamyl transpeptidase (gamma-GT) were observed. However, no such relationships were noticed for cadmium. It is concluded that lead may be one of the pollutants indirectly affecting semen quality by altering the functions of accessory sex glands.

Testicular and spermatotoxic effect of nitrate in mice

A study was conducted with nitrate to assess the testicular and spermatotoxic effects in mice at doses to which human beings are exposed as well as at higher dose levels in the drinking water. Potassium nitrate was administered to mice at dose levels 90, 200, 500, 700 and 900 ppm for 35 days. There was no difference in the uptake of water in control and treated animals. The amount of nitrate intake/ mouse/day calculated on the basis of water intake in the different groups ranged from 22.5 to 27, 50 to 60, 125 to 150, 175 to 210 and 225 to 270 mg/kg body weight. No changes were evident in the body weight, testicular, epididymal and accessory organ weight at all the dose levels tested, although a decline in sperm count and sperm motility along with an increase in abnormal sperm was noticed at 900 ppm. The activity of marker testicular enzymes, mainly 17-beta hydroxysteroid dehydrogenase (17-betaHSD) and gamma glutamyl transpeptidase (gamma-GT), associated with specific cell types were altered. Histopathological changes including atrophy and disturbed spermatogenesis were observed only at the 900-ppm dose level. In conclusion, we can say that the testicular and spermatotoxic effects are observed only at the highest dose level, which is not likely to be encountered in the drinking water.

Male reproductive effect of arsenic in mice

Arsenic, a known human carcinogen, was given to mice via drinking water as sodium arsenite at a dose 53.39, 133.47, 266.95 and 533.90 micromol 1 for 35 days. A decrease in the activity of 17 beta HSD along with increase in LDH, gammaGT activity were observed at 533.90 micromol l. The observed sperm count, motility and morphological abnormalities in sperm were similar to control at lower dose levels. However at 533.90 micromol l a significant decrease in sperm count and motility along with increase in abnormal sperm were noticed. Significant accumulation of arsenic in testes and accessory sex organs may be attributed to the arsenic binding to the tissues or greater cellular uptake. No effects were observed on indices studied for reproductive effects at 53.39 micromol l arsenic close to which human being are exposed through drinking water under the present set of experimental conditions.

Chlorinated pesticides and heavy metals in human semen

The concentration of chlorinated pesticides and heavy metals (lead and cadmium) was measured using gas liquid chromatography and the graphite tube atomizer of atomic absorption spectrophotometer, respectively, in semen samples collected from men in the normal human population. Significant concentrations of lead and cadmium were detected. Significant amounts of hexachlorocyclohexane (HCH) and its isomers alpha, beta, gamma and delta, the dichlorodiphenyl trichloroethane (DDT) metabolite 1,1,1-trichloro-2,2-bis (p chlorophenyl ethane) (pp'-DDE) and low values of 1,1,2-dichloro-2, 2-bis(p chlorophenyl ethane) (pp'-DDD) aldrin or endosulfan were detected. The presence of these xenobiotics in human semen might be related to the extensive use of pesticides, emission of exhaust from motor vehicles, consumption of tobacco and industrial operations.

Induction of chromosome aberrations, micronucleus formation and sperm abnormalities in mouse following carbofuran exposure

Carbofuran was tested to study in vivo cytogenetic effects in mouse bone marrow cells and morphological alterations in sperms. The acute oral and intraperitoneal (i.p.) LD(50) of carbofuran was determined to be 9.5 or 2.0 mg/kg b.w. in mice, respectively. The animals were orally administered 1.9, 3.8 or 5.7 mg/kg b.w. (20, 40 and 60% of LD(50)) of carbofuran for 24 h or 1.9 mg/kg b.w. for 4 consecutive days (cumulative 7.6 mg/kg or 80% of LD(50)) to analyse chromosome aberrations (CAs). For micronucleus test (MT) animals were orally exposed to 5.7 mg/kg b.w. for 24 and 48 h or 1.9 mg/kg b.w. for 4 consecutive days. For reference mice were exposed to peanut oil (negative control) and cyclophosphamide (20 mg/kg) or ethyl methanesulfonate (EMS: 100 mg/kg) positive control for CAs and MT respectively. To analyse the effect on sperm morphology mice were exposed to single i.p. dose of 1 and 2 mg/kg b.w. of carbofuran and repeatedly to 0.5 mg/kg for 5 consecutive days. Cytogenetic analysis revealed that all the test doses induced mitotic inhibition, CAs, micronucleus (MN) formation and sperm abnormalities in a dose dependent manner. Present observations concurrent with earlier reports substantiate the genotoxic potential of carbofuran and possible risk to human beings.

Hexachlorocyclohexane and its isomers: regional brain levels in the rat after dermal exposure

In the present study the distribution of hexachlorocyclohexane (HCH) and its isomers in the brain of rats given dermal exposure of this pesticide have been investigated using a gas liquid chromatographic technique. The male Druckery rats were given dermal exposure of HCH 50 or 100 mg/kg body weight/day in 0.2 ml acetone for the period of 60 or 120 days. The results reveal that an appreciable quantity of HCH and its isomers alpha, beta, gamma, and delta accumulate in a dose- and time-dependent manner in different regions of the brain, which may adversely affect the specific physiological function of these brain regions.

In utero and lactational exposure of carbofuran to rats: effect on testes and sperm

Male offspring of adult females treated with 0.2 or 0.4 mg/kg during either the whole of pregnancy or the whole of the lactation period did not induce generalised toxic effects. A significant alteration in enzymatic activities i.e. SDH (decreased), LDH and Y-GT (increased) were observed in testes only at 0.4 mg/kg. A decrease in sperm motility, sperm count along with increase in percent abnormal sperm was observed at 0.4 mg/kg dose level. Histopathological examination revealed loss of spermato-genesis, degenerative changes in Sertoli cells which are well supported with biochemical studies indicating that carbofuran interferes with the maturation process of testis. No such effects were observed at 0.2 mg/kg. The testicular and spermatotoxic effects observed in rats given in utero or lactational exposure may be due to transfer of carbofuran or its metabolites through placenta or mothers milk.

Spermatotoxic effects of carbaryl in rats

The spermatotoxic effect of carbaryl in adult and young male rats has been examined. Carbaryl 50 and 100 mg/kg b.wt. Male fed 5 d/week for 60 days, caused dose and age-dependent decline in epididymal sperm count and sperm motility, an increase in sperm with abnormal morphology. The dose of 25 mg/kg/d was a 'No observed effect level' for the indices studied. Young animals in comparison to adults exhibited pronounced spermatotoxic effects.

Effect of oral administration of carbofuran on male reproductive system of rat

1. Carbofuran was administered orally to adult male rats at dose levels of 0.1, 0.2, 0.4 or 0.8 mg kg-1 body weight, 5 d wk-1 for 60 days. A dose dependent decrease was observed in body weight of rats treated with 0.2-0.8 mg carbofuran kg-1 body weight. 2. A significant decrease in the weight of epididymides, seminal vesicles, ventral prostate and coagulating glands was observed at various test doses of carbofuran except at the lowest dose. 3. Decreased sperm motility, reduced epididymal sperm count along with increased morphological abnormalities in head, neck and tail regions of spermatozoa were observed in rats exposed to 0.2, 0.4, or 0.8 mg carbofuran kg-1 body weight. 4. In addition, significant alterations were observed in the activities of marker testicular enzymes viz. sorbitol dehydrogenase (SDH), glucose-6-P-dehydrogenase (G6PDH) (decreased), lactate dehydrogenase (LDH) and gamma-glutamyl transpeptidase (gamma-GT) (increased) depending on dose. 5. Histologically, the results indicated the toxicity of carbofuran on testes depending on dose. The changes predominantly consisted of moderate oedema, congestion, damage to Sertoli cells and germ cells, along with the accumulation of cellular debris and presence of giant cells in the lumen of a few seminiferous tubules which showed disturbed spermatogenesis with the higher doses of carbofuran. 6. These observations determined a no effect level dose of 0.1 mg kg-1 body weight of carbofuran on the biochemical and morphological indices studied for male reproductive toxicity assessment in the rat model. The results of the present study provide first hand information on the reproductive toxicity of carbofuran in male rats.

Effects of carbaryl on the rat's male reproductive system

Carbaryl was orally administered to male albino rats at 50 mg or 100 mg carbaryl/kg body weight 5 d/w for 90 d. A significant decrease in weight gain was observed at the high dosage after 60 d. Although no significant changes in the weight of testes, epididymides and accessory sex organs occurred, moderate to marked histopathological changes in the testes were seen at both dosage levels. Testicular enzymes associated with post-meiotic spermatogenic cells (sorbitol dehydrogenase) decreased, while lactate dehydrogenase increased concomitant with the observed degeneration of spermatogenic cells. Enzymes associated with pre-meiotic spermatogenic cells or Sertoli cells (gamma-glutamyl transpeptidase) increased, while glucose-6-phosphate dehydrogenase decreased. These effects were dose related and associated with declines in epididymal sperm count and percent sperm motility and increased abnormal sperm morphology.

Effect of dermal application of hexachlorocyclohexane (HCH) on male reproductive system of rat

1. The toxic manifestations of dermally applied hexachlorocyclohexane (50 mg or 100 mg kg-1 body weight day-1, 5 days in a week for 120 days) on testes and sperm of rat have been investigated. 2. The results indicate that exposure of HCH through the dermal route could lead to an alteration in the activities of marker testicular enzymes viz. sorbitol dehydrogenase (SDH), glucose-6-P-dehydrogenase (G6PDH), gamma-glutamyl transpeptidase (gamma-GT) and beta-glucuronidase (beta Gluc.) associated with specific cell types. 3. Significant quantities of HCH and its isomers accumulated in testes as well as sperm of treated rats. 4. HCH exposure also led to a decrease in serum testosterone levels, epididymal sperm count, sperm motility and an increase in the percentage of abnormal sperm. 5. These observations indicate the possibility of adverse effects of HCH on the male reproductive functions of men exposed dermally to this pesticide in industry or during spraying in the field.

Binding of a high affinity phosphotyrosyl peptide to the Src SH2 domain: crystal structures of the complexed and peptide-free forms

The crystal structure of the Src SH2 domain complexed with a high affinity 11-residue phosphopeptide has been determined at 2.7 A resolution by X-ray diffraction. The peptide binds in an extended conformation and makes primary interactions with the SH2 domain at six central residues: PQ(pY)EEI. The phosphotyrosine and the isoleucine are tightly bound by two well-defined pockets on the protein surface, resulting in a complex that resembles a two-pronged plug engaging a two-holed socket. The glutamate residues are in solvent-exposed environments in the vicinity of basic side chains of the SH2 domain, and the two N-terminal residues cap the phosphotyrosine-binding site. The crystal structure of Src SH2 in the absence of peptide has been determined at 2.5 A resolution, and comparison with the structure of the high affinity complex reveals only localized and relatively small changes.

Crystal structure of the phosphotyrosine recognition domain SH2 of v-src complexed with tyrosine-phosphorylated peptides

Three-dimensional structures of complexes of the SH2 domain of the v-src oncogene product with two phosphotyrosyl peptides have been determined by X-ray crystallography at resolutions of 1.5 and 2.0 A, respectively. A central antiparallel beta-sheet in the structure is flanked by two alpha-helices, with peptide binding mediated by the sheet, intervening loops and one of the helices. The specific recognition of phosphotyrosine involves amino-aromatic interactions between lysine and arginine side chains and the ring system in addition to hydrogen-bonding interactions with the phosphate.