Published online Sep 26, 2015. doi: 10.4252/wjsc.v7.i8.1109
Peer-review started: September 5, 2014
First decision: December 23, 2014
Revised: August 1, 2015
Accepted: August 13, 2015
Article in press: August 14, 2015
Published online: September 26, 2015
Processing time: 386 Days and 2.8 Hours
Endogenous “stem cell niche” (SCN) accompanying vessels contains immune system components which in vivo determine differentiation of multi potent stem cells toward proper cell types in given tissue. Combinations of sex steroids may represent novel chemical approach for neuronal areas of regenerative medicine, since they cause transformation of vascular smooth muscle stem cells into differentiating neuronal cells. Circulating sex steroids are present during pregnancy and can be utilized where needed, when various embryonic/fetal tissues develop from their stem cells. Utilization of induced regeneration of tissues (regenerative medicine) is expected being more effective in sudden failures of younger individuals carrying intact SCN, as compared to established chronic disorders caused by SCN alteration. An essential component of SCN are monocyte-derived cells exhibiting tissue-specific “stop effect” (SE) preventing, for instance, an aging of neuronal cells. Its alteration causes that implantation of neuronal stem cells will also result in their differentiation toward aging cells. When we repair the SE by supply of circulating mononuclear cells from young healthy individuals, we may be able to provide novel regenerative treatments of age-induced neural diseases by sex steroid combinations. Questions regarding some age-induced body alterations are also addressed.
Core tip: Sex steroid combinations have been found to transdifferentiate in vitro the vascular smooth muscle cells into neurons. Therefore, utilization of sex steroid combinations may enable regeneration of neural tissues affected by acute/traumatic disorders. In aging individuals, however, an altered immune system components in the stem cell niche may be unable to preserve regenerating cells in the functional stage due to the immune system regression with age advancement. This could be improved by transfer of blood mononuclear cells from young healthy individuals. Beside that, the local and systemic utilization of honey bee propolis alone has been found to ameliorate some age-induced disorders.