Interleukin-4/STAT6 signaling impairs the survival of mouse astroglia in vivo but not in vitro

Neurogenesis is limited in mammalian brains and Alzheimer’s disease conditions further reduce the neurogenic output. Recent findings suggest that reduced neurogenesis could be one of the reasons underlying the exacerbated neuropathology in humans, and restoring the neural stem cell proliferation and neurogenesis could help circumventing some pathological aspects of Alzheimer’s disease. We recently identified Interleukin-4/STAT6 signaling as a neuron-glia crosstalk mechanism that enables glial proliferation and neurogenesis in adult zebrafish brain and 3D cultures of human astroglia, which manifest neurogenic properties. In this study, we tested whether activating IL4/STAT6 signaling in adult mouse astroglia would enhance cell proliferation and neurogenesis in health and disease conditions. By using single cell sequencing in APP/PS1dE9 mouse model of AD, we found that IL4 receptor (Il4r) is not expressed in mouse astroglia. Lentivirus-mediated expression of IL4R or constitutively active STAT6V impaired the survival capacity of mouse astroglia in vivo but not in vitro. Our findings suggest that adult mouse brain generates a non-permissive environment that dictates a negative effect of IL4 signaling on astroglial survival and neurogenic properties in contrast to zebrafish brains and in vitro mammalian cell cultures. single-cell sequencing performed from 12 months old mice (single-mice) dentate gyrus