Evaluation of toxicity of 4-octylphenol in TM4 Sertoli cells: an in vitro study.

The reproductive toxicity of 4-octylphenol (4-OP) has been studied in animals such as mouse and fish. In humans, the exposure of sperm to 4-OP has been shown to decrease motility and viability. In this study, we performed an in vitro assessment of the toxic effects of 4-OP on mouse TM4 Sertoli cells and investigated the underlying molecular mechanisms. TM4 cells were treated with four concentrations (0, 10, 30, and 50 µM) of 4-OP at the following time points: 24, 48, and 72 h. Cell viability and apoptosis assays were conducted following 4-OP exposure. We found that 4-OP significantly decreased cell viability in a concentration- and time-dependent manner, and increased apoptosis. Quantitative PCR analysis showed that the mRNA expression levels of BCL2 Associated X, Apoptosis Regulator (Bax) and BCL2 Antagonist/Killer (Bak) increased while that of BCL2 Apoptosis Regulator (Bcl-2) decreased in 4-OP-exposed cells compared with that in the controls. Western blotting revealed that 4-OP induced caspase-3 activity and Bad phosphorylation in a concentration- and time-dependent manner. Additionally, cytochrome C protein did not colocalize with mitochondrial marker dye by 24 h. Cytochrome c protein expression increased in a time-dependent manner upon exposure to 50 µM 4-OP. These results suggest that 4-OP induces mitochondria-mediated apoptosis through regulation of Bcl-2 family proteins and caspase-3 activation in male Sertoli cells.

Fermented Colostrum Whey Upregulates Aquaporin-3 Expression in, and Proliferation of, Keratinocytes via p38/c-Jun N-Terminal Kinase Activation.

Colostrum, which contains various immune and growth factors, aids wound healing by promoting keratinocyte proliferation. Aquaporins (AQPs) are small, hydrophobic membrane proteins that regulate cellular water retention. However, few studies have examined the effect of processed colostrum whey on AQP-3 expression in human skin cells. Here, we investigated the effect of milk, colostrum, fermented milk, and fermented colostrum whey on AQP-3 expression in keratinocyte HaCaT cells. Concentrations of 100-400 µg/mL of fermented colostrum whey were found to induce HaCaT cell proliferation. AQP-3 was found to be expressed exclusively in HaCaT cells. AQP-3 expression was significantly increased in 100 µg/mL fermented colostrum whey-treated cells compared with that in controls. Moreover, fermented colostrum increased p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) phosphorylation, but not ERK1/2 phosphorylation. Thus, our results suggest that fermented colostrum whey increased AQP-3 expression in, and the proliferation of, keratinocytes via JNK and p38 MAPK activation.