Ultrasound of 10 MHz frequency as a novel strategy for skin anti-aging therapy.

摘要

Aging is believed to be connected with accumulated damaging of cellular macromolecules in non-dividing cells as well as with reduction of the cells capability to repair this damage. Damage of the macromolecules occurs through different physical and chemical factors (e.g. different types of irradiation, heat, toxins, etc.). The fate of the damaged macromolecules is dependent on such processes as degradation of unstable proteins, refolding of misfolded proteins, controlling of regulatory proteins and prevention of protein folding. These processes are essentially regulated through activation of heat shock proteins (HSPs) [1,2]. HSP family includes different proteins classified according to their molecular weights. Among them the HSP70 and HSP90 seems to be responsible for the recognition and refolding of proteins. HSPs are present in all cell types and were found not only inside of the cells where they believed to act cyto-protectively (to prevent the cells against the second stress that would otherwise cause lethal molecular damage) but also in the cell membrane and in the extracellular space where they can show the cytotoxic effect increasing the cell death [3,4]. It is well known that HSPs are over-expressed in cancer cells as well as on outer cellular membranes of damaged cells after some aggressive treatments (e.g. [5]). There is also increasing evidence of HSPs expression in different neurodegenerative disorders, during inflammation, by trauma as well as by cerebral and cardiac ischemia. It is believed that in the most of these diseases induction of a heat shock response might be an effective prophylactic treatment to minimize the severe injuries, making HSPs activation a potential therapeutic modality.