Extract of the mycelium of T. matsutake inhibits elastase activity and TPA-induced MMP-1 expression in human fibroblasts

Skin aging is induced through complex biological processes in human skin caused by proteolysis of collagen and elastin, two structural proteins of the dermal extracellular matrix (ECM). Collagen and elastin degradation can induce the expression of matrix metalloproteinases (MMPs), as well as that of a family of zinc-dependent endopeptidases that play critical roles in skin aging. Moreover, elastase is a metalloproteinase which acts on the degradation of elastin in skin aging, and is also involved in the inhibition or the repair of wrinkle formation. Extract of the mycelium of Tricholoma matsutake (T. matsutake), or pine mushroom, is widely distributed in Asian countries. The extract is from the natural biomaterial of the mushroom which is rich in polysaccharides, including β-glucan. This extract has shown potent bioactive antioxidant, immunomodulatory and antitumoral properties. In the present study, we investigated whether the extract of the mycelium of T. matsutake has effects on elastase activity, as well as on the expression of tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) and MMP-1 under basal conditions. Our results revealed that the extract of the mycelium of T. matsutake significantly decreased elastase activity in a dose-dependent manner and reduced the levels of MMP-1 and MMP-3. On the other hand, the expression of TIMP-1 and tropoelastin was increased in fibroblasts treated with the extract of the mycelium of T. matsutake. However, collagent expression was not affected. In addition, our results demonstrated that the extract of the mycelium of T. matsutake inhibited the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced MMP-1 expression and suppressed TPA-induced p38 activity. Therefore, the inhibitory effects of the extract of the mycelium of T. matsutake on MMP-1 induction are mediated by the inhibition of p38 in human fibroblasts. Our data suggest that the extract of the mycelium of T. matsutake may prove to be an effective biomaterial for anti-wrinkle treatment, as it can obstruct the degradation of the dermal ECM.