Can Intranasal Administration of Adipose-Derived Stem Cells Reach and Affect the Histological Structure of Distant Organs of Aged Wistar Rat?

INTRODUCTION: Stem cell therapy is a highly promising strategy in various degenerative diseases. Intranasal administration of stem cells could be considered as a non-invasive treatment option. However, there is great debate concerning the ability of stem cells to reach distant organs. It is also unclear in such a case if they can alleviate age-related structural changes in these organs. AIM: The aim of this study is to evaluate the ability of intranasal administration of adipose-derived stem cells (ADSCs) to reach distant organs of rats at different time intervals and to investigate their effects on age-related structural changes in these organs. MATERIALS AND METHODS: Forty-nine female Wistar rats were used in this study, seven of which were adults (6-month-old) and 42 were aged (2-year-old). Rats were divided into three-groups: Group-I (adult control), Group-II (aged), and Group-III (aged ADSCs treated). Rats of Groups I and II were sacrificed after 15 days from the beginning of the experiment. Rats of Group III were treated with intranasal ADSCs and were sacrificed after 2-h, 1-day, 3-day, 5-day, and 15-day. Heart, liver, kidney, and spleen specimens were collected and processed for H and E, CD105 immunohistochemistry, and immunofluorescent techniques. Morphometric study and statistical analysis were performed. RESULTS: ADSCs appeared in all organs examined after 2-h of intranasal administration. Their maximum presence was detected after 3-day of administration, after which their immunofluorescence gradually decreased and nearly disappeared from these organs by the 15(th) day. Improvement of some age-related deterioration in the structure of the kidney and liver occurred at day 5 after intranasal administration. CONCLUSIONS: ADSCs effectively reached the heart, liver, kidney, and spleen after intranasal administration. ADSCs ameliorated some age-related changes in these organs.