1
|
Trichomonas vaginalis infection impairs anion secretion in vaginal epithelium. PLoS Negl Trop Dis 2021; 15:e0009319. [PMID: 33861752 PMCID: PMC8051796 DOI: 10.1371/journal.pntd.0009319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 03/22/2021] [Indexed: 12/04/2022] Open
Abstract
Trichomonas vaginalis is a common protozoan parasite, which causes trichomoniasis associated with severe adverse reproductive outcomes. However, the underlying pathogenesis has not been fully understood. As the first line of defense against invading pathogens, the vaginal epithelial cells are highly responsive to environmental stimuli and contribute to the formation of the optimal luminal fluid microenvironment. The cystic fibrosis transmembrane conductance regulator (CFTR), an anion channel widely distributed at the apical membrane of epithelial cells, plays a crucial role in mediating the secretion of Cl− and HCO3−. In this study, we investigated the effect of T. vaginalis on vaginal epithelial ion transport elicited by prostaglandin E2 (PGE2), a major prostaglandin in the semen. Luminal administration of PGE2 triggered a remarkable and sustained increase of short-circuit current (ISC) in rat vaginal epithelium, which was mainly due to Cl− and HCO3− secretion mediated by the cAMP-activated CFTR. However, T. vaginalis infection significantly abrogated the ISC response evoked by PGE2, indicating impaired transepithelial anion transport via CFTR. Using a primary cell culture system of rat vaginal epithelium and a human vaginal epithelial cell line, we demonstrated that the expression of CFTR was significantly down-regulated after T. vaginalis infection. In addition, defective Cl− transport function of CFTR was observed in T. vaginalis-infected cells by measuring intracellular Cl− signals. Conclusively, T. vaginalis restrained exogenous PGE2-induced anion secretion through down-regulation of CFTR in vaginal epithelium. These results provide novel insights into the intervention of reproductive complications associated with T. vaginalis infection such as infertility and disequilibrium in vaginal fluid microenvironment. Trichomonas vaginalis is a common sexually transmitted parasite that colonized the urogenital mucosa and causes trichomoniasis, a neglected sexually transmitted infection associated with multiple adverse reproductive outcomes in humans. However, the underlying mechanisms remain largely unknown. The epithelial cystic fibrosis transmembrane conductance regulator (CFTR) is an anion channel conducting both Cl− and HCO3−, which participates in the regulation of luminal fluid microenvironment conducive to the success of reproductive events. Prostaglandin E2 (PGE2), a bioactive molecule abundant in human seminal fluid, has been demonstrated to exhibit a robust pro-secretory action by activating CFTR in the female genital tract epithelial cells such as endometrial epithelium. These discoveries motivated the authors to investigate the effect of T. vaginalis infection on exogenous PGE2-induced transepithelial transport of electrolytes in vagina. Here, we found that in rat vaginal epithelium, luminal administration of PGE2 elicited a response of Cl− and HCO3− secretion mediated by cAMP-activated CFTR. However, T. vaginalis infection impaired transepithelial anion transport evoked by PGE2, which is probably related to the defective expression and function of CFTR. These outcomes may complement and expand our knowledge of the complex interaction between T. vaginalis and the infected host, providing a novel therapeutic strategy for disequilibrium in vaginal fluid microenvironment and infertility induced by T. vaginalis infection.
Collapse
|
2
|
Loh SH, Tsai YT, Huang SF, Yu TC, Kuo PC, Chao SC, Chou MF, Tsai CS, Lee SP. Effects of Andrographolide on Intracellular pH Regulation, Cellular Migration, and Apoptosis in Human Cervical Cancer Cells †. Cancers (Basel) 2020; 12:cancers12020387. [PMID: 32046125 PMCID: PMC7072207 DOI: 10.3390/cancers12020387] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 02/03/2020] [Accepted: 02/04/2020] [Indexed: 12/15/2022] Open
Abstract
Cancer cells have been characterized with alkaline intracellular pH (pHi) values (≥7.2) to enable cancer proliferation, migration, and progression. The aim of the present study was to explore the concentration-dependent effects of Andrographolide, an active diterpenoid compound of herb Andrographis paniculata, on Na+/H+ exchanger isoform 1 (NHE1), cellular migration and apoptosis in human cervical cancer cells (HeLa). The pHi was detected by microspectrofluorometry method, and intracellular acidification was induced by NH4Cl prepulse technique. Viability and protein expression were determined by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and Western blot, respectively. Human normal endocervical cells (End1), ectocervical cells (Ect1), and HeLa were bought commercially. The resting pHi value of HeLa (≈7.47) was significantly higher than that of End1 and Ect1 (≈7.30), and shifted from alkaline to acidic following acid/base impacts. In HEPES (4-(2-Hydroxyethyl)piperazine-1-ethanesulfonic acid | N-(2-Hydroxyethyl)piperazine-N′-(2-ethanesulfonic acid) -buffered superfusate, NHE1 and V-ATPase co-existed functionally for acid extrusion in HeLa, while only NHE1 existed functionally in End/Ect1. Andrographolide (3–1000 μM) concentration-dependently inhibited NHE1 activity. Cell-migration and expressions of NHE1, V-ATPase, PARP (poly-ADP-ribose-polymerase), pro-Caspase-3, and Bcl-2 were significantly reduced by pretreating with Andrographolide (≥100 μM) for 24–48 h in HeLa. Andrographolide inhibited cell viability of End1-cells/Ect1 and HeLa (≥100 and ≥30 μM, respectively). The present findings implicate the promising clinical applications of Andrographolide on cervical cancer treatment.
Collapse
Affiliation(s)
- Shih-Hurng Loh
- Department of Clinical Pharmacy, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan; (S.-H.L.); (S.-F.H.); (M.-F.C.)
- Department of Pharmacology, National Defense Medical Center, Taipei 11490, Taiwan; (T.-C.Y.); (P.-C.K.)
| | - Yi-Ting Tsai
- Division of Cardiovascular Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan; (Y.-T.T.); (C.-S.T.)
| | - Shu-Fu Huang
- Department of Clinical Pharmacy, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan; (S.-H.L.); (S.-F.H.); (M.-F.C.)
| | - Tien-Chieh Yu
- Department of Pharmacology, National Defense Medical Center, Taipei 11490, Taiwan; (T.-C.Y.); (P.-C.K.)
| | - Pei-Chun Kuo
- Department of Pharmacology, National Defense Medical Center, Taipei 11490, Taiwan; (T.-C.Y.); (P.-C.K.)
| | - Shih-Chi Chao
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 11490, Taiwan;
| | - Mei-Fang Chou
- Department of Clinical Pharmacy, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan; (S.-H.L.); (S.-F.H.); (M.-F.C.)
| | - Chien-Sung Tsai
- Division of Cardiovascular Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan; (Y.-T.T.); (C.-S.T.)
| | - Shiao-Pieng Lee
- Department of Biomedical Engineering, National Defense Medical Center, Taipei 11490, Taiwan
- Department of Oral and Maxillofacial Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan
- Correspondence:
| |
Collapse
|