International Journal of Nanomedicine (Sep 2018)
Effect of young exosomes injected in aged mice
Abstract
Bo-Ram Lee,1,* Jung-Hee Kim,1,* Eun-Sook Choi,1,2 Jung-Hoon Cho,3 Eunjoo Kim1,2 1Companion Diagnostics and Medical Technology Research Group, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea; 2Global Center for Bio-Convergence Spin System (BicSPINS), Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea; 3School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang 37666, Republic of Korea *These authors contributed equally to this work Introduction: Exosomes, nano-sized extracellular vesicles, are known to circulate through the blood stream to transfer molecular signals from tissue to tissue. Methods: To determine whether exosomes affect aging in animals, we primarily identified the changes in exosomal miRNA contents during the aging process. In exosomes from 12-month-old mice, mmu-miR-126-5p and mmu-miR-466c-5p levels were decreased and mmu-miR-184-3p and mmu-miR-200b-5p levels were increased significantly compared with those of 3-month-old mice. Their levels in exosomes were partially correlated with those in tissues: levels of only mmu-miR-126-5p and mmu-miR-466c-5p in lungs and/or liver were decreased, but those of mmu-miR-184-3p and mmu-miR-200b-5p in tissues did not coincide with those of exosomes. Results and discussion: In the aged tissues injected with young exosomes isolated from serum, mmu-miR-126b-5p levels were reversed in the lungs and liver. Expression changes in aging-associated molecules in young exosome-injected mice were obvious: p16Ink4A, MTOR, and IGF1R were significantly downregulated in the lungs and/or liver of old mice. In addition, telomerase-related genes such as Men1, Mre11a, Tep1, Terf2, Tert, and Tnks were significantly upregulated in the liver of old mice after injection of young exosomes. Conclusion: These results indicate that exosomes from young mice could reverse the expression pattern of aging-associated molecules in aged mice. Eventually, exosomes may be used as a novel approach for the treatment and diagnosis of aging animals. Keywords: exosome, injection, reverse aging, telomerase, biomarker, molecular therapy
