Tribenoside has been used clinically for hemorrhoidal disease associated with coagulation,
inflammation, and
wounds. However, the pharmacological mechanism of
tribenoside activity has never been clear. In this study we examined whether
tribenoside affected expression and deposition of laminins that are required for reconstruction of basement membranes (BMs) during wound healing in hemorrhoidal disease. HaCaT cells, which are derived from human epidermis, were treated in growth media supplemented with
tribenoside.
Reverse transcriptase-polymerase chain reaction (RT-PCR) using primers specific for
laminin chains showed that HaCaT cells constitutively expressed
laminin alpha3, alpha5, beta1, beta3, gamma1, and gamma2 chains.
Tribenoside treatment of HaCaT cells did not induce expression of other
laminin chains. We also quantified the expression of
laminin chains in
tribenoside-treated cells using real-time PCR. The expression level of
laminin alpha3, beta1, beta3, gamma1, and gamma2 chains was not affected. In contrast, the expression of
laminin alpha5 in the
tribenoside-treated cells was four times higher than that of control cells. Immunocytochemistry also showed that
tribenoside accelerated the focal deposition of laminin-332 (alpha3, beta3, gamma2). These results suggest that
tribenoside interacts with epidermal cells and regulates the expression and localization of laminins to help reconstruct BMs in wound healing of
hemorrhoids.