Flutamide alters the distribution of c-Src and affects the N-cadherin-ß-catenin complex in the seminiferous epithelium of adult rat.

This study was undertaken to explore interactions between c-Src kinase and the N-cadherin-ß-catenin complex in seminiferous tubules of flutamide-treated rats. An anti-androgen flutamide (50 mg/kg bw) was injected daily into adult rats from postnatal days 82 to 88. Testes from 90-day-old control and flutamide-treated rats were used for experiments. Flutamide did not affect testis morphology, but impaired connexin43 immunoexpression between Sertoli cells at the blood-testis barrier (BTB) region, indicating the BTB as a sensitive target for flutamide. Real-time RT-PCR and western blot analyses revealed upregulation of N-cadherin at the mRNA and protein level after flutamide exposure (p < 0.05), whereas no changes in ß-catenin and c-Src expression were observed. Notably, membranous ß-catenin immunolocalization indicated its involvement in the cell adhesion complex rather than its contribution to the Wnt signaling pathway. As we used an exposure regime which avoided germ cell loss, it is likely that changes in the N-cadherin-ß-catenin complex are a primary effect of androgen signaling disruption by flutamide. Immunohistochemistry revealed a diffusion of N-cadherin and ß-catenin signals away from the BTB with concomitant disruption of c-Src staining pattern. As detected by immunofluorescence and coimmunoprecipitation, flutamide promoted disassembly of the N-cadherin-ß-catenin complex, induced N-cadherin to dissociate from c-Src at the BTB site, and altered interactions between the cell junction proteins and/or c-Src. Equally important, increased levels of p-N-cadherin-Tyr860 and p-ß-catenin-Tyr654 (p < 0.05) pointed to a mechanism related to adhesion complex disassembly and suggested a potential role of c-Src in the control of the protein-protein dynamics. Overall, for the first time we have shown that flutamide alters the distribution of c-Src and affects N-cadherin-ß-catenin interactions at the BTB. Understanding mechanism(s) by which anti-androgens can affect intercellular adhesion within the testis is relevant for predicting and preventing reproductive disorders affecting male fertility.

Postnatal exposure to flutamide affects CDH1 and CTNNB1 gene expression in adult pig epididymis and prostate and alters metabolism of testosterone.

In both epididymis and prostate the dynamic cross-talk between the cells is hormonally regulated and, in part, through direct cell-to-cell interactions. Functionality of the male reproductive organs may be affected by exposure to specific chemicals, so-called 'reprotoxicants'. In this study we tested whether early postnatal and prepubertal exposure to anti-androgen flutamide altered the expression of adherens junction genes encoding E-cadherin (CDH1) and ß-catenin (CTNNB1) in adult pig epididymis and prostate. In addition, the expression of mRNAs and proteins for 5α-reductase (ST5AR2) and aromatase (CYP19A1) were examined to show whether flutamide alters metabolism of testosterone. Thus, flutamide was injected into male piglets between Days 2 and 10 and between Days 90 and 98 postnatally (PD2 and PD90; 50 mg/kg bw), tissues that were obtained on postnatal Day 270. To assess the expression of the genes and proteins, real-time RT-PCR and Western blot were performed respectively. Moreover, adherens junction proteins were localized by immunohistochemistry. In response to flutamide, CDH1 and CTNNB1 expressions were down-regulated along the epididymis, mostly in PD2 group (p < 0.001, p < 0.01). In the prostate, CDH1 mRNA and protein expressions were significantly down-regulated (p < 0.01), whereas CTNNB1 mRNA was slightly up-regulated in both flutamide-treated groups. CTNNB1 protein level was markedly elevated in both PD2 (p < 0.001) and PD90 (p < 0.01) groups. In the epididymis, the expression of ST5AR2 and CYP19A1 was down- and up-regulated, respectively (p < 0.05), whereas in the prostate evident decrease in CYP19A1 expression (p < 0.001, p < 0.01, p < 0.05) was demonstrated. In both tissues, membranous immunolocalization of CTNNB1 suggests its involvement in cell-cell adhesion. Overall, flutamide administration resulted in suppression of androgen action in the epididymis and prostate leading to deregulation of CDH1 and CTNNB1 gene expressions which is probably caused by the alterations in the expression of ST5AR2 and CYP19A1 in both reproductive organs.

Do active substances of thymus influence the processes of aging? VIII. Cerebral superoxide dismutase activity and malonyl dialdehyde concentration in aging mice treated with embryonal and early fetal thymic calf extracts (ETCE) and mature calf thymic extracts (thymex L and TFX).

Cerebral superoxide dismutase (SOD) activity and malonyl dialdehyde (MDA) concentration were determined in 450 day female BNe strain mice. These animals were previously treated with 45 injections of: 1. embryonal and early fetal thymic calf extracts (ETCE) in single doses of 1.0 mg (group E) and 7.5 mg (group EE) protein per mouse; 2. Thymex L in the same doses (groups T and TT, respectively); 3. TFX in a single dose on 1.0 mg protein per animal. All applied thymic extracts, independently of the kind and dose, caused a fall in brain SOD activity. A statistically significant decrease in MDA concentration was found in the brains of E group mice. A clinical implication of the results has been suggested.