Effect of Arsenate and p-Phenylenediamine on the Expression of Aquaporins in Cultured Human Urothelial Cells

Yi-Hsiao Wu; Kuan-Hung Lai; Chienn-Chung Chen; Tung-Mao Lai; Po-Wei Huang

doi:10.7759/cureus.43606

Effect of Arsenate and p-Phenylenediamine on the Expression of Aquaporins in Cultured Human Urothelial Cells

Cureus. 2023 Aug 16;15(8):e43606. doi: 10.7759/cureus.43606. eCollection 2023 Aug.

Authors

Yi-Hsiao Wu¹, Kuan-Hung Lai², Chienn-Chung Chen³, Tung-Mao Lai⁴, Po-Wei Huang^{5

6}

Affiliations

¹ Division of Cardiovascular Surgery, Department of Surgery, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung, TWN.
² Division of Plastic Surgery, Department of Surgery, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung, TWN.
³ Department of Plastic Surgery, E-DA Hospital, Kaohsiung, TWN.
⁴ Department of Plastic Surgery, E-Da Hospital, Kaohsiung, TWN.
⁵ Center of General Education, Shu Zen Junior College of Medicine and Management, Kaohsiung, TWN.
⁶ Division of Urology, Department of Surgery, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung, TWN.

Abstract

Background: Exposure to arsenic (As) or p‑phenylenediamine (PPD) can lead to dysfunction, or even cancer, in various types of organs, including the urinary bladder, yet the underlying mechanisms remain unclear. Aquaporins (AQPs) are widely expressed small water channel proteins that provide the major route for the transport of water and other small molecules across plasma membranes in diverse cell types. Altered expression of AQPs has been associated with pathologies in all major organs, including the urinary bladder.

Objective: The present in vitro study was performed as a first step towards exploring the possible involvement of AQPs in As- and PPD‑induced bladder diseases.

Methods: An immortalized normal human urothelial cell line was employed. Cells were exposed to different concentrations of sodium arsenate (0‑20 μM) or PPD (0‑200 μM) for 48 h. Cell viability was subsequently assessed. The mRNA and protein expression levels of AQPs (specifically, AQP3, 4, 7, 9, and 11) were analyzed using reverse transcription‑quantitative polymerase chain reaction and Western blot analyses, respectively.

Results: The viability of the cells was decreased in a concentration-dependent manner upon exposure to arsenate. The mRNA and protein expression levels of AQP3, 4, 7, and 9 were substantially reduced, whereas the expression of AQP11 was largely unchanged. As for the experiments with PPD, treatment with increasing concentrations of PPD induced a gradual decrease in cell viability. The mRNA and protein expression levels of AQP3, 4, and 11 were generally unaltered; however, a marked reduction in the expression levels of AQP7 was observed, contrasting with a gradual concentration-dependent decrease in the expression of AQP9.

Conclusion: The importance of the differential expression profiles of the AQPs induced by arsenate and PPD requires further investigation; nevertheless, the findings of the present study suggest that AQPs have a role in As‑ and PPD‑induced bladder diseases.

Keywords: aquaporin; arsenate; p-phenylenediamine; urinary bladder; urothelial cell.