Aging Skin: Nourishing from Out-In. Lessons from Wound Healing

Skin lesion therapy, peculiarly in the elderly, cannot be isolated from understanding that the skin is an important organ consisting of different tissues. Furthermore, dermis health is fundamental for epidermis integrity, and so adequate nourishment is mandatory in maintaining skin integrity. The dermis nourishes the epidermis, and a healthy epidermis protects the dermis from the environment, so nourishing the dermis through the epidermal barrier is a technical problem yet to be resolved. This is also a consequence of the laws and regulations restricting cosmetics, which cannot have properties that pass the epidermal layer. There is higher investment in cosmetics than in the pharmaceutical industry dealing with skin therapies, because the costs of drug registration are enormous and the field is unprofitable. Still, wound healing may be seen as an opportunity to “feed” the dermis directly. It could also verify whether providing substrates could promote efficient healing and test optimal skin integrity maintenance, if not skin rejuvenation, in an ever aging population

Gene expression in lungs of mice lacking the 5-hydroxytryptamine transporter gene

<p>Abstract</p> <p>Background</p> <p>While modulation of the serotonin transporter (5HTT) has shown to be a risk factor for pulmonary arterial hypertension for almost 40 years, there is a lack of in vivo data about the broad molecular effects of pulmonary inhibition of 5HTT. Previous studies have suggested effects on inflammation, proliferation, and vasoconstriction. The goal of this study was to determine which of these were supported by alterations in gene expression in serotonin transporter knockout mice.</p> <p>Methods</p> <p>Eight week old normoxic mice with a 5-HTT knock-out (5HTT-/-) and their heterozygote(5HTT+/-) or wild-type(5HTT+/+) littermates had right ventricular systolic pressure(RVSP) assessed, lungs collected for RNA, pooled, and used in duplicate in Affymetrix array analysis. Representative genes were confirmed by quantitative RT-PCR and western blot.</p> <p>Results</p> <p>RVSP was normal in all groups. Only 124 genes were reliably changed between 5HTT-/- and 5HTT+/+ mice. More than half of these were either involved in inflammatory response or muscle function and organization; in addition, some matrix, heme oxygenase, developmental, and energy metabolism genes showed altered expression. Quantitative RT-PCR for examples from each major group confirmed changes seen by array, with an intermediate level in 5HTT +/- mice.</p> <p>Conclusion</p> <p>These results for the first time show the in vivo effects of 5HTT knockout in lungs, and show that many of the downstream mechanisms suggested by cell culture and ex vivo experiments are also operational in vivo. This suggests that the effect of 5HTT on pulmonary vascular function arises from its impact on several systems, including vasoreactivity, proliferation, and immune function.</p