Additive effect of bFGF and selenium on expansion and paracrine action of human amniotic fluid-derived mesenchymal stem cells

Abstract

BackgroundMesenchymal stem cell-derived conditioned medium (MSC-CM) has emerged as a promising cell-free tool for restoring degenerative diseases and treating traumatic injuries. The present study describes the effect of selenium as a reactive oxygen species (ROS) scavenger and its additive effect with basic fibroblast growth factor (bFGF) on in vitro expansion of amniotic fluid (AF)-MSCs and the paracrine actions of AF-MSC-CM as well as the associated cellular and molecular mechanisms.MethodsIn this study, we obtained CM from human AF-MSCs cultured with selenium. The stemness of selenium-treated AF-MSCs was evaluated by cell growth and differentiation potential. Human fibroblasts were treated with AF-MSC-CM and analyzed for cell signaling changes. For in vivo wound healing assay, ICR mice with a full-thickness skin wound were used.ResultsSelenium played a critical role in in vitro expansion of AF-MSCs through activation of the AKT-ERK1/2, Smad2, and Stat3 signaling pathways along with inactivation of GSK3β. When administered together with bFGF, it showed remarkable effect in inhibiting ROS accumulation and preserving their multipotency. Proliferation and migration of human dermal fibroblasts and in vivo wound healing were improved in the CMs derived from AF-MSCs exposed to selenium and bFGF, which was caused by the Smad2, AKT-MEK1/2-ERK, and NFκB signaling triggered by the paracrine factors of AF-MSCs, such as TGF-β, VEGF, and IL-6. Our results suggest the following: (a) supplementation of selenium in AF-MSC culture contributes to in vitro expansion and preservation of multipotency, (b) ROS accumulation causes progressive losses in proliferative and differentiation potential, (c) the separate activities of bFGF and selenium in MSCs exert an additive effect when used together, and (d) the additive combination improves the therapeutic effects of AF-MSC-derived CMs on tissue repair and regeneration.ConclusionAntioxidants, such as selenium, should be considered as an essential supplement for eliciting the paracrine effects of MSC-CMs.Electronic supplementary materialThe online version of this article (10.1186/s13287-018-1058-z) contains supplementary material, which is available to authorized users.

Low Selenium Levels in Amniotic Fluid Correlate with Small-For-Gestational Age Newborns

“…The GPx activity in maternal and cord plasma as well as placental tissue was shown to be lower in pre-eclamptic pregnancies [ 15 , 30 , 46 , 49 ]. As previously described, amniotic fluid represents an important material for understanding the biological effects of Se [ 35 , 37 ]. Roy et al reported Se levels in amniotic fluid samples.…”

“…Studies show that ROS impacts cellular senescence and that this process is mediated by antioxidants such as glutathione, ascorbic acid, and ROS connected enzymes. Thus, by reducing ROS levels, one could improve DNA damage, prevent apoptosis, and recover mitochondrial dysfunction [ 37 ]. Therefore, in order to better understand the biological background Se has on growth amniotic fluid, it is an important biological material to study.…”

Overexpression of Nanog in amniotic fluid–derived mesenchymal stem cells accelerates dermal papilla cell activity and promotes hair follicle regeneration

“…AF-MSCs were obtained by amniocentesis performed for fetal karyotyping between 16 and 20 weeks of gestation. AF-MSCs, previously characterized as MSCs by verification of their differentiation, proliferation, and immunological phenotypes 17 , were used in this study. All experiments were performed in triplicate on independently isolated AF-MSCs.…”

“…Differentiation of MSCs was performed as previously described 17 . Briefly, 3 × 10 4 MSCs/well were seeded in 6-well culture dishes and cultured in proliferation media to reach 100% confluence.…”

“…Differentiation of MSCs was performed as previously described 17 . Briefly, 3 × 10 4 cells/well were seeded in 6-well culture dishes, cultured in proliferation media to 70–80% confluence, and then cultured for 2.5 weeks in osteogenic induction medium [Iscove’s Modified Dulbecco’s Medium (IMDM) basal medium (Gibco/Invitrogen) supplemented with 5 μM dexamethasone, 10 mM β-glycerophosphate, 0.2 mM ascorbate, and 10% FBS] or control medium (IMDM basal medium supplemented with 10% FBS).…”