Abstract
The purpose of this study was to determine whether exposure of cultured chemically transformed hamster oral keratinocytes (HCPC-1) to an aqueous extract of smokeless tobacco (STE) potentiates DNA synthesis elicited by vasoactive intestinal peptide (VIP), an autocrine neuropeptide, and, if so, whether this response is associated with inactivation of neutral endopeptidase 24.11 (NEP 24. 11), an ectoenzyme that cleaves and inactivates VIP very effectively, in these cells. I found that STE and VIP each elicited a modest, albeit significant, increase in DNA synthesis in cultured HCPC-1 cells (P < 0.05). However, incubation of HCPC-1 cells with STE together with VIP evoked a significant, concentration- dependent increase in DNA synthesis that was mediated by VIP receptors. The effects of STE and VIP were synergistic. Maximal response was observed after a 48-h incubation. STE significantly attenuated NEP 24.11 activity in HCPC-1 cells at a time when VIP-induced DNA synthesis was maximal. Collectively, these data indicate that STE potentiates VIP-induced DNA synthesis in cultured oral keratinocytes, and that this response is temporally related to STE-induced inactivation of NEP 24.11 in these cells. I suggest that NEP 24.11 modulates the mitogenic effects of smokeless tobacco in the oral epithelium, in part, by inactivating VIP.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
