Secretome of Differentiated PC12 Cells Restores the Monocrotophos-Induced Damages in Human Mesenchymal Stem Cells and SHSY-5Y Cells: Role of Autophagy and Mitochondrial Dynamics
A perturbed cellular homeostasis is a key factor associated with xenobiotic exposure resulting in various ailments. The local cellular microenvironment enriched with secretory components aids in cell–cell communication that restores this homeostasis. Deciphering the underlying mechanism behind this restorative potential of secretome could serve as a possible solution to many health hazards. We, therefore, explored the protective efficacy of the secretome of differentiated PC12 cells with emphasis on induction of autophagy and mitochondrial biogenesis. Monocrotophos (MCP), a widely used neurotoxic organophosphate, was used as the test compound at sublethal concentration. The conditioned medium (CM) of differentiated PC12 cells comprising of their secretome restored the cell viability, oxidative stress and apoptotic cell death in MCP-challenged human mesenchymal stem cells and SHSY-5Y, a human neuroblastoma cell line. Delving further to identify the underlying mechanism of this restorative effect we observed a marked increase in the expression of autophagy markers LC3, Beclin-1, Atg5 and Atg7. Exposure to autophagy inhibitor, 3-methyladenine, led to a reduced expression of these markers with a concomitant increase in the expression of pro-apoptotic caspase-3. Besides that, the increased mitochondrial fission in MCP-exposed cells was balanced with increased fusion in the presence of CM facilitated by AMPK/SIRT1/PGC-1α signaling cascade. Mitochondrial dysfunctions are strongly associated with autophagy activation and as per our findings, cellular secretome too induces autophagy. Therefore, connecting these three potential apices can be a major breakthrough in repair and rescue of xenobiotic-damaged tissues and cells.
KeywordsSecretome Conditioned medium PC12 cells Mesenchymal stem cells Autophagy Mitochondrial dynamics
Financial support from Council of Scientific & Industrial Research, Government of India, New Delhi, India [Grant No. BSC0111/INDEPTH/CSIR Network Project] and Department of Science and Technology, Ministry of Science and Technology, Government of India, New Delhi, India [Grant No. SR/SO/Z 36/2007/91/10] is acknowledged.
Compliance with Ethical Standards
Conflict of interest
All authors declare that they have no conflict of interest.
- Beer, L., Zimmermann, M., Mitterbauer, A., Ellinger, A., Gruber, F., Narzt, M.-S., et al. (2015). Analysis of the secretome of apoptotic peripheral blood mononuclear cells: Impact of released proteins and exosomes for tissue regeneration. Scientific reports, 5, 16662.CrossRefPubMedCentralPubMedGoogle Scholar
- Birkenfeld, A. L., Lee, H.-Y., Guebre-Egziabher, F., Alves, T. C., Jurczak, M. J., Jornayvaz, F. R., et al. (2011). Deletion of the mammalian INDY homolog mimics aspects of dietary restriction and protects against adiposity and insulin resistance in mice. Cell Metabolism, 14(2), 184–195.CrossRefPubMedCentralPubMedGoogle Scholar
- Chaabane, W., User, S. D., El-Gazzah, M., Jaksik, R., Sajjadi, E., Rzeszowska-Wolny, J., et al. (2013). Autophagy, apoptosis, mitoptosis and necrosis: Interdependence between those pathways and effects on cancer. Archivum Immunologiae et Therapiae Experimentalis, 61(1), 43–58.CrossRefPubMedGoogle Scholar
- Doeppner, T. R., Traut, V., Heidenreich, A., Kaltwasser, B., Bosche, B., Bähr, M., et al. (2016). Conditioned medium derived from neural progenitor cells induces long-term post-ischemic neuroprotection, sustained neurological recovery, neurogenesis, and angiogenesis. Molecular neurobiology, 1-10.Google Scholar
- Duan, Z., Qu, Y., Zhao, F., Tang, B., Li, J., & Mu, D. (2010). Protective effect of conditioned medium from astrocytes transfected with telomerase reverse transcriptase on hypoxia-ischemia neurons. Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi=. Chinese Journal of Reparative and Reconstructive Surgery, 24(10), 1217–1223.PubMedGoogle Scholar
- Gerencser, A. A., Chinopoulos, C., Birket, M. J., Jastroch, M., Vitelli, C., Nicholls, D. G., et al. (2012). Quantitative measurement of mitochondrial membrane potential in cultured cells: Calcium-induced de-and hyperpolarization of neuronal mitochondria. The Journal of Physiology, 590(12), 2845–2871.CrossRefPubMedCentralPubMedGoogle Scholar
- Kumar, V., & Prakash, C. (2015). Arsenic induced oxidative stress and mitochondrial dysfunction in rat brain. SpringerPlus, 4(S1), 1–32.Google Scholar
- Lahiani, A., Zahavi, E., Netzer, N., Ofir, R., Pinzur, L., Raveh, S., et al. (2015). Human placental expanded (PLX) mesenchymal-like adherent stromal cells confer neuroprotection to nerve growth factor (NGF)-differentiated PC12 cells exposed to ischemia by secretion of IL-6 and VEGF. Biochimica et Biophysica Acta (BBA)-Molecular. Cell Research, 1853(2), 422–430.Google Scholar
- Sun, H., Bénardais, K., Stanslowsky, N., Thau-Habermann, N., Hensel, N., Huang, D., et al. (2013). Therapeutic potential of mesenchymal stromal cells and MSC conditioned medium in amyotrophic lateral sclerosis (ALS)-in vitro evidence from primary motor neuron cultures, NSC-34 cells, astrocytes and microglia. PLoS ONE, 8(9), e72926.CrossRefPubMedCentralPubMedGoogle Scholar
- Teixeira, F. G., Carvalho, M. M., Panchalingam, K. M., Rodrigues, A. J., Mendes-Pinheiro, B., Anjo, S., et al. (2016). Impact of the Secretome of human mesenchymal stem cells on brain structure and animal behavior in a rat model of Parkinson’s disease. Stem Cells Translational, 6, 634–646.CrossRefGoogle Scholar