mfat‐1 transgene protects cultured adult neural stem cells against cobalt chloride‐mediated hypoxic injury by activating Nrf2/ARE pathways

Abstract

Ischemic stroke is a devastating neurological disorder and one of the leading causes of death and serious disability in adults. Adult neural stem cell (NSC) replacement therapy is a promising treatment for both structural and functional neurological recovery. However, for the treatment to work, adult NSCs must be protected against hypoxic-ischemic damage in the ischemic penumbra. In the present study, we aimed to investigate the neuroprotective effects of the mfat-1 transgene on cobalt chloride (CoCl 2 )-induced hypoxic-ischemic injury in cultured adult NSCs as well as its underlying mechanisms. The results show that in the CoCl 2 -induced hypoxic-ischemic injury model, the mfat-1 transgene enhanced the viability of adult NSCs and suppressed CoCl 2 -mediated apoptosis of adult NSCs. Additionally, the mfat-1 transgene promoted the proliferation of NSCs as shown by increased bromodeoxyuridine labeling of adult NSCs. This process was related to the reduction of reactive oxygen species. Quantitative real-time polymerase chain reaction and Western blot analysis revealed a much higher expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream genes (HO-1, NQO-1, GCLC). Taken together, our findings show that the mfat-1 transgene restored the CoCl 2 -inhibited viability and proliferation of NSCs by activating nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response elements (ARE) signal pathway to inhibit oxidative stress injury.

Protective effect of high n-3/n-6 PUFA ratio on acute hypoxic-ischemic brain damage in mfat-1 transgenic mice and possible inflammation-related targets identified by transcriptome analysis

“…Without interference from long-term dietary of other bioactive compounds, the transgenic mice proved to be a better model compared with exogenous supplementation. Consistent with our pervious report [26], the n-3 PUFAs in the brains of mfat-1 mice not only contain a higher proportion of DHA, but also contain EPA and DPA that are almost absent in the brain of WT mice, which leading to an increase in the overall n-3/n-6 PUFA ratio. The overall increase in n-3 PUFAs should be better than exogenous supplementation of speci c kind of n-3 PUFAs.…”

“…The mfat-1 transgenic mice were obtained by prokaryotic microinjection as previous report [26], the coding region of C. elegans fat-1 cDNA was optimized to enhance the expression of fat-1 in mammalian cells. The mfat-1 heterozygotes of C57BL/6J and wild-type (WT) C57BL/6J mice were crossed to produce mfat-1 transgene mice and WT littermates.…”

“…The fat-1 gene encoded an n-3 fatty acid desaturase that could introduce a double bond into n-6 fatty acids at the n-3 position of their hydrocarbon chains to form n-3 fatty acids, hence converting n-6 PUFAs to n-3 PUFAs [25]. In mfat-1 transgenic mice, the coding region of C. elegans fat-1 cDNA was optimized to enhance the expression of fat-1 in mammalian cells [26]. Therefore, mfat-1 transgenic mice were ideal for addressing the effects of n-3/n-6 ratio in the body tissues for elimination of the need to manipulate the diet, which will avoid the possible confounding effects of dietary supplements in the study [27,28].…”

Mesenchymal stem cell‑derived extracellular vesicles prevent neural stem cell hypoxia injury via promoting miR‑210‑3p expression

“…cobalt chloride triggered nSc apoptosis and caused nSc hypoxic injury (21,22). The signaling pathways involved in nSc apoptosis have been investigated; Mfat-1 transgene protects nScs against cobalt chloride-mediated hypoxic injury by activating nrf2/are signaling pathways (21). The present study demonstrated that MSc-eVs also protected nScs against cobalt chloride-induced nSc apoptosis.…”

“…collectively, the results indicated that MSc-eVs possibly reduced apoptosis by modulating the mir-210-3p/aiF/BniP3 signaling pathway. cobalt chloride triggered nSc apoptosis and caused nSc hypoxic injury (21,22). The signaling pathways involved in nSc apoptosis have been investigated; Mfat-1 transgene protects nScs against cobalt chloride-mediated hypoxic injury by activating nrf2/are signaling pathways (21).…”