Hypoxic Preconditioning Induces Neuronal Differentiation of Infrapatellar Fat Pad Stem Cells through Epigenetic Alteration

Abstract

Hypoxia is considered a key factor in cellular differentiation and proliferation, particularly during embryonic development; the process of early neurogenesis also occurs under hypoxic conditions. Apart from these developmental processes, hypoxia preconditioning or mild hypoxic sensitization develops resistance against ischemic stroke in deteriorating tissues. We therefore hypothesized that neurons resulting from hypoxia-regulated neuronal differentiation could be the best choice for treating brain ischemia, which contributes to neurodegeneration. In this study, infrapatellar fat pad (IFP), an adipose tissue present beneath the knee joint, was used as the stem cell source. IFP-derived stem cells (IFPSCs) are totally adherent and are mesenchymal stem cells. The transdifferentiation protocol involved hypoxia preconditioning, the use of hypoxic-conditioned medium, and maintenance in maturation medium with α-lipoic acid. The differentiated cells were characterized using microscopy, reverse transcription PCR, real time PCR, and immunocytochemistry. To evaluate the epigenetic reprogramming of IFPSCs to become neuron-like cells, methylation microarrays were performed. Hypoxia preconditioning stabilized and allowed for the translocation of hypoxia inducible factor 1α into the nucleus and induced achaete-scute homologue 1 and doublecortin expression. Following induction, the resultant cells expressed neuronal markers neuron-specific enolase, neurofilament-light chain, growth associated protein 43, synaptosome associated protein 25, and β-III tubulin. The differentiated neural-lineage cells had functional gene expression pertaining to neurotransmitters, their release, and their receptors. The molecular signaling mechanisms regulated developmental neurogenesis. Furthermore, the in vitro physiological condition regulated neurotransmitter respecification or switching during IFPSC differentiation to neurons. Thus, differentiated neurons were fabricated against the ischemic region to treat neurodegenerative diseases.

Reduction of Deuterium Level Supports Resistance of Neurons to Glucose Deprivation and Hypoxia: Study in Cultures of Neurons and on Animals

“…On the other hand, the overproduction of reactive oxygen species [ 36 , 37 ], and at the next stage, lipid peroxidation [ 38 ], is an integral part of the general “adaptation-stress” syndrome [ 39 ]. In this case, the activation of free radical processes also serves as a nonspecific signal for the mobilization of the body’s defense systems [ 40 , 41 , 42 , 43 ], including the activation of antioxidant defense mechanisms [ 44 ], which is a typical reaction of the biological system to an effect that unbalances it from the state of physiological equilibrium [ 45 , 46 , 47 , 48 ].…”

Autophagy Regulates the Effects of Adipose-Derived Stem Cell Small Extracellular Vesicles On Lipopolysaccharide-Induced Pulmonary Microvascular Barrier Damage

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Autophagy regulates the effects of ADSC-derived small extracellular vesicles on acute lung injury

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