Comparison of toxicity of CdSe: ZnS quantum dots on male reproductive system in different stages of development in mice

Background: Quantum dots [QDs] are new types of fluorescent materials for biological labeling. QDs toxicity study is an essential requirement for future clinical applications. Therefore, this study aimed to evaluate cytotoxic effects of CdSe: ZnS QDs on male reproductive system

Materials and Methods: In this experimental study, the different concentrations of CdSe: ZnS QDs [10, 20 and 40 mg/kg] were injected to 32 male mice [adult group] and 24 pregnant mice [embryo group] on day 8 of gestation. The histological changes of testis and epididymis were studied by a light microscopy, and the number of seminiferous tubules between two groups was compared. One-way analysis of variance [one-way Anova] using the Statistical Package for the Social Sciences [SPSS, SPSS Inc., USA] version 16 were performed for statistical analysis

Results: In adult group, histological studies of testis tissues showed a high toxicity of CdSe: ZnS in 40 mg/kg dose followed by a decrease in lamina propria; destruction in interstitial tissue; deformation of seminiferous tubules; and a reduction in number of spermatogonia, sper-matocytes, and spermatids. However, there was an interesting result in fetal testis development, meaning there was no significant effect on morphology and structure of the seminiferous tubules and number of sperm stem cells. Also histological study of epididymis tissues in both groups [adult and embryo groups] showed no significant effect on morphology and structure of tubule and epithelial cells, but there was a considerable reduction in number of spermatozoa in the lumen of the epididymal duct in 40 mg/kg dose of adult group

Conclusion: The toxicity of QDs on testicular tissue of the mice embryo and adult are different before and after puberty. Due to lack of research in this field, this study can be an introduction to evaluate the toxicity of QDs on male reproduction system in different stages of development

vivo effects of quantum dot on organs development before maturity

The field of nanotechnology is rapidly expanding .The development quantum dots quantum dot [QDs], show great promise for treatment and diagnosis of cancer and targeted drug delivery little data on the toxicity of QDs, especially for in vivo applications, are available. As a result, concerns exist over their toxicity for in vivo applications. Then, cytotoxic effects of cadmium selenide [CdSe] quantum dots on organs development before maturity were studied in this study. One month old male Mice treated by injection of CdSe at the doses of 10, 20 and 40 mg/kg. Structural and optical properties of quantum dots were studied by XRD, UV-Vis absorption spectrum and Scanning Tunneling Microscopy and the number of cells in seminiferous tubes of various groups were analyzed using SPSS 16 program [one way ANOVA test]. Histological studies of testis tissue showed high toxicity of cdse in the dose of 40 mg/kg which followed by decrease in lamina propria thickness, destruction in interstitial tissue, deformation of seminiferoustubes, and reduction in number cells. Also histological study of lung tissue showed in 20 and 40 mg/kg doses destruction in interstitial and epithelium tissues. On the whole, this study showed high toxicity of cdse on development of testis and lung tissues, even in low doses considering lack of literature review in this field, this study can be an introduction to researches about toxicity effect of quantum dots on development of organs

[Effects of endosulfan on the reproductive parameters of male rats]

Endosulfan is an organochlorine compound with insecticidal and acaricidal properties and also with widespread agricultural use for insect control. The poison could enter the body through respiration, absorption via skin and ingestion in human beings, or grazing by farm animals. The long-term effects of endosulfan EC 35% on sex hormones and sperm morphology were studied in mature male rats. In this study, 40 male rats were divided into five groups: the control group did not receive any substances while the placebo group received normal saline and the three test groups, respectively received endosulfan 5, 10 and 20 ml/kg of the total body weight every two days for three weeks. At the end of the experiment, the rats were anesthetized by chloroform and blood samples were collected from their heart for sex hormone evaluation. The rats were later sacrificed and their testes and epididymides were harvested for morphological studies of sperm. Following endosulfan administration, LH and FSH concentrations increased significantly [p<0.05] while testosterone underwent a meaningful decrease. Moreover, reproductive parameters such as sperm count, motility and testicular weight decreased significantly compared to the control group [p<0.05]. It seems that endosulfan has an undeniably damaging effect on the testis accompanied by its unfavorable effects on the reproductive system which may lead to infertility due to the changes in sex hormones concentration and sperm count and motility

Flow cytometry: a novel approach for indirect assessment of protamine deficiency by CMA3 staining, taking into account the presence of M540 or apoptotic bodies

Chromomycin A3 [CMA3] staining, either by the slide method or fluorescence microscopy, is widely used for indirect assessment of protamine deficiency in a semen sample. Flow cytometry is the most suitable tool to improve assessment accuracy, both in terms of statistical analysis and for prevention of observer variation. This study provides a simple procedure to account for merocyanine 540 [M540] or apoptotic bodies, which result in underestimation of the percentage of CMA3 positivity, by using propidium iodide [PI] staining. Therefore, this study aims to evaluate the percentage of CMA3 by PI staining to exclude M540 bodies that prevent underestimation of CMA3 staining. This study is an experimental study. Semen samples collected from 104 infertile men who referred to the Andrology Unit of the Isfahan Fertility and Infertility Center were initially assessed according to World Health Organization [WHO] criteria. Samples were washed twice with Ham's. Each sample was divided into two portions, a control and the other processed for density gradient centrifugation [DGC]. Each portion was assessed for CMA3 staining by both the slide and flow cytometry methods. Coefficients of correlation and student t-test were carried out using the Statistical Package for the Social Studies [SPSS 11.5]. Detection of CMA3 staining was more appropriate with fluorescence detector 3 [FL-3] rather than fluorescence detector 2 [FL-2] in the evaluation of protamine deficiency to exclude M540 bodies. This study, for the first time, provides the basis for assessment of CMA3 staining for flow cytometry. However, since the maximum excitation for CMA3 is not covered by the 488 nm laser, we recommend further experimentation using a flow cytometer with optimal excitation