Occupational and Lifestyle Exposures on Male Infertility: A Mini Review

Tobacco and alcohol as factors for male infertility-a public health approach

BACKGROUND

The study of reproductive characteristics of 430 male subjects of different age, fertility status and educational level who were involved in the program of extracorporeal fertilization at the Clinic of Gynecology and Obstetrics, Clinical Centre Niš, examined their knowledge, attitudes and behavior regarding tobacco and alcohol consumption as lifestyle risk predictors of their partial or full infertility.

METHODOLOGY

Consisted of the analyses of spermiograms to establish their fertility status and a survey of their attitudes towards smoking and alcohol use (behavior, knowledge of the general health and reproductive health consequences of such a lifestyle, and their determination to change it).

RESULTS

The proportion with higher tobacco consumption and more severe forms of infertility increased significantly with ageing (P < 0.001); the highest daily consumption of alcohol and the incidence of intoxication was seen among azoospermic patients; the level of awareness of the harmful effects of tobacco was highest among normozoospermic subjects and the highest level of determination to quit smoking was statistically significantly present among azoospermic subjects.

CONCLUSION

Appropriate use of health promotion activities in relation to alcohol and tobacco use is through specially designed programs.

Selenium and L-Carnitine Ameliorate Reproductive Toxicity Induced by Cadmium in Male Mice

Cadmium (Cd) has been reported to reduce male fertility, impair reproductive capacity, and play a major role in the pathogenesis of infertility. This study was conducted to investigate the possible protective role of Selenium (Se) and L-carnitine (LC) against the adverse effects induced by Cd on the male reproductive system in mice. Animals were randomly divided into seven groups (n = 10); control group and six treated groups, as follows: Cd (0.35 mg/kg), Se (0.87 mg/kg), LC (10 mg/kg), and a combination of either Se or LC and then a combination of both with Cd, and all animals were injected for a period of 30 days. Exposure of Cd showed a significant decrease in enzymatic antioxidant activities, deficiency in reproductive performance, decrease serum testosterone level, severe changes in the histopathological architecture, and higher degree of damages and appearance of unblemished DNA strands. Treatment with Se and LC has the highly synergistic and ameliorates the damaging effect of Cd on the testis through the elevation of the enzymatic antioxidant and diminish histopathological abnormalities and DNA damage.

Male infertility among bakers associated with exposure to high environmental temperature at the workplace

Objective

This study aimed to evaluate the prevalence of male infertility among bakers exposed to high environmental temperature.

Methods

This cross-sectional study was conducted to obtain information using a validated questionnaire administered through an interview. The mean wet bulb globe temperature (WBGT) index in the bakeries was measured. A new statistical formula was used to estimate the prevalence of infertility among bakers.

Results

A total of 137 bakers working in 20 bakeries and 107 individuals included in the comparable control group with variations in age, race, marital status, and income and with history of cigarette smoking were recruited. Using a newly devised formula, the prevalence of infertility among the exposed group was 22.7%, compared with 3.0% in the control group (p = 0.013). All possible confounding factors associated with infertility among bakers were excluded such as cigarette smoking, age, and race. There were unfavorable hot working conditions in bakeries, with a WBGT index of 37.4 °C, while the average WBGT for offices was 25.5 °C (p < 0.0001).

Conclusion

Our study showed that the rate of infertility among bakers was high, which resulted from exposure to high environmental temperature at the workplace as evidenced by the WBGT index. This finding should alert the healthcare authorities to take necessary measures under the labor code to curtail infertility among bakers.

Low doses of chlorpyrifos interfere with spermatogenesis of rats through reduction of sex hormones

Use of pesticides results in indirect effects on human health. We aimed to evaluate implications of toxicological effects of subchronic chlorpyrifos exposure on reproductive function in male rats. A total of 48 adult Wistar male rats were separated into four groups (n = 12). Animals were gavaged with 2.5 mg/kg (T1), 5 mg/kg (T2), or 10 mg/kg (T3) body weight of chlorpyrifos (CPF) or distilled water (control) daily for 30 days. Organ weights, epididymal sperm parameters, DNA integrity, sex hormonal (FHS and LH) levels, and alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), and creatinine concentrations were determined on day 31. Another two sets of (four groups/set; n = 10) animals were orally treated with the same doses of CPF, control animal groups were treated with distilled water only for 30 days, and fertility indices and blood plasma acetylcholine esterase (AchE) were determined on day 31. Exposure to CPF resulted in a significant (p < 0.05) decrease in weights of testis and epididymis. An increase in liver weight resulted in reduced sperm counts and sperm motility and an increase in sperm abnormalities. Significant reduction in serum testosterone (p < 0.01), luteinizing hormone (p < 0.05), and follicular stimulating hormone (p < 0.05) levels was evident in animals treated with the highest dose. A significant decrease in the number of viable implantation sites and pups was observed in female rats mated with the T3 (p < 0.01) and T2 (p < 0.05) males. The ALT, AST, GGT, and creatinine contents were significantly increased (p < 0.05 and p < 0.01, respectively) on CPF exposure. A significant (p < 0.01) reduction in blood plasma AchE enzyme was observed with the highest dose. Our results demonstrated that prolonged exposure of CPF induces spermatogenesis damage, possibly through interference with sex hormones and AchE enzyme resulting in reduction of fertility. Therefore, awareness programs on handling CPF (pesticides) to enhance safety warrant minimization of its hazards.

Exposición a COVs en fábricas de muebles de dos poblaciones del norte de Colombia

<p><strong>Objetivos</strong> Evaluar la exposición a compuestos orgánicos volátiles (COVs) en trabajadores de fábricas artesanales de mueblesde dos poblaciones de Sucre (Sincelejo y Sampués), Norte de Colombia. Determinar posibles signos y/o síntomas relacionados con la exposición a estos contaminantes.</p><p><strong>Métodos </strong>Estudio transversal analíticocon aplicación de una encuesta. La población objetivo estuvo conformada por 66 individuos, 41 expuestos y 25 controles. Se tomaron muestras personales para las concentraciones de benceno, tolueno, etilbenceno y xilenos (en ambos grupos) y se contrastó con posibles efectos en la salud atribuidos a estos contaminantes.</p><p><strong>Resultados </strong>Las concentraciones de benceno, tolueno y m/p-xileno fueron mayores en el grupo expuesto (9,5 mg/m³, 8,1 mg/m³ y 12,1 mg/m³) en comparación con el grupo control(0,2 mg/m³, 0,3 mg/m³ y 0,03 mg/m³).Dolor muscular 82,9 % (RP=3,8; IC95%:1,2-11,8) y somnolencia 65,9 % (RP=4,9; IC95%:1,7-14,7)estuvieron asociados a mayor exposición (p&lt; 0,05). Factores como el uso de mezclas solventes (thinner) en el trabajo y el tráfico vehicularpueden contribuir a estos resultados.</p><p><strong>Conclusiones </strong>La contribución de diversas fuentes aumenta la exposición personal a los COVs, de los trabajadores de las fábricas artesanales de muebles en el Norte de Colombia. Adicionalmente, el uso excesivo de estos compuestos puede estar generando efectos adversos en la salud de los trabajadores.</p>

Correlation between spermatogenesis disorders and rat testes CYP2E1 mRNA contents under experimental alcoholism or type I diabetes

PURPOSE

The aim of the study was to investigate the correlation between spermatogenesis disorders and CYP2E1 mRNA contents in testes of rats with experimental alcoholism or type I diabetes.

MATERIAL/METHODS

Two pathological states characterized by CYP2E1 induction were simulated on Wistar male rats: experimental alcoholism and type I diabetes. As controls for each state, equal number of animals (of the same age and weight) were used. Morphological evaluation of rat testes was carried out. The spermatogenic epithelium state was estimated by four points system. CYP2E1 mRNA expression was rated by method of reverse transcriptase polymerase chain reaction. Pearson correlation coefficients were used for describing relationships between variables.

RESULTS

The presence of alcoholism and diabetes-mediated quantitative and qualitative changes in male rat spermatogenic epithelium in comparison with norm has been demonstrated. The increased levels of testes CYP2E1 have been fixed simultaneously. CYP2E1 mRNA content negatively strongly correlated with spermatogenic index value (r=-0.99; P<0.001) and positively strongly correlated with epithelium desquamation occurrence (r=0.99; P<0.001) in testes of rats with chronic alcoholism. The strong correlation between CYP2E1 mRNA content and number of spermatogonia (r=0.99; P<0.001) and "windows" occurrence (r=0.96; P<0.001) has been fixed in diabetic rats testes.

CONCLUSIONS

Present investigation has demonstrated that the testicular failure following chronic ethanol consumption and diabetes type I in male rats accompanied CYP2E1 mRNA over-expression in testes. The correlation between the levels of CYP2E1 mRNA in testes and spermatogenesis disorders allow supposing the involvement of CYP2E1 into the non-specific pathogenetic mechanisms of male infertility under above-mentioned pathologies.

Damage of testicular cell macromolecules and reproductive capacity of male rats following co-administration of ethambutol, rifampicin, isoniazid and pyrazinamide

The necessity to minimize adverse effects of tuberculosis chemotherapy requires a comprehensive evaluation of the effects of antituberculosis drugs on the reproductive system and testicular cell macromolecules. The epidemiological situation of tuberculosis in Central and Eastern Europe is getting worse. Data on adverse effects of antituberculosis drugs are scare concerning particularly their effects on the reproductive system. The aim of the present study was to investigate the potential effect of ethambutol, rifampicin, isoniazid and pyrazinamide co-administration on lipid peroxidation, glutathione content and protein SH-groups, DNA fragmentation levels, the reproductive capacity of Wistar male rats and the antenatal development of their posterity. The rats (150-170 g) were divided into two groups: group I - received antituberculosis drugs suspended in 1% starch gel per os: ethambutol - 155 mg/kg b.w./day, rifampicin - 74.4 mg/kg b.w./day, isoniazid - 62 mg/kg b.w./day, pyrazinamide - 217 mg/kg b.w./day, group II (control) - received only starch gel in corresponding volumes. The contents of TBA-active compounds, glutathione and protein SH-groups in testis and sperm were determined spectrophotometrically, the DNA-fragmentation was determined using an UV transilluminator (BIORAD, USA), reproductive system indices were measured by standard methods. The co-administration of therapeutic doses of ethambutol, isoniazid, rifampicin and pyrazinamide to male rats during the period of spermatogenesis caused an increase in the rate of thiobarbituric acid reactive substances formation in testis and sperm, decrease of testis glutathione and protein SH-group contents, significant changes in DNA fragmentation, fatal decrease of male fertilizing capacity and fertility, and increase of pre- and post-implantation embryo lethality. The changes in reproductive indices could be the result of direct or indirect effects of one or more drugs investigated.

Helping patients through the pain of infertility

While males and combined couple factors play a large part in infertility cases, women often carry the physical, social, and emotional burden of these diagnoses. Nurse practitioners are in a prime position to assess women at risk for infertility, initiate an investigation to identify potential etiologies, refer women to specialized centers, and provide them with ongoing care and support through this difficult period in their lives.