In Vivo AAV1 Transduction With hRheb(S16H) Protects Hippocampal Neurons by BDNF Production

Abstract

Recent evidence has shown that Ras homolog enriched in brain (Rheb) is dysregulated in Alzheimer's disease (AD) brains. However, it is still unclear whether Rheb activation contributes to the survival and protection of hippocampal neurons in the adult brain. To assess the effects of active Rheb in hippocampal neurons in vivo, we transfected neurons in the cornu ammonis 1 (CA1) region in normal adult rats with an adeno-associated virus containing the constitutively active human Rheb (hRheb(S16H)) and evaluated the effects on thrombin-induced neurotoxicity. Transduction with hRheb(S16H) significantly induced neurotrophic effects in hippocampal neurons through activation of mammalian target of rapamycin complex 1 (mTORC1) without side effects such as long-term potentiation impairment and seizures from the alteration of cytoarchitecture, and the expression of hRheb(S16H) prevented thrombin-induced neurodegeneration in vivo, an effect that was diminished by treatment with specific neutralizing antibodies against brain-derived neurotrophic factor (BDNF). In addition, our results showed that the basal mTORC1 activity might be insufficient to mediate the level of BDNF expression, but hRheb(S16H)-activated mTORC1 stimulated BDNF production in hippocampal neurons. These results suggest that viral vector transduction with hRheb(S16H) may have therapeutic value in the treatment of neurodegenerative diseases such as AD.

DNMT3a in the hippocampal CA1 is crucial in the acquisition of morphine self‐administration in rats

“…AAV2‐Dnmt3a and AAV2‐Control were bilaterally microinjected into the hippocampal CA1 (1.0 μL/side) based on the published studies . We used the same coordinates mentioned above.…”

Neurotrophic Factors and Their Potential Applications in Tissue Regeneration

“…Virus mediated delivery of BDNF into the hippocampal neurons in normal rats (Jeon et al 2015) or the striatum of quinolinic acid-induced Huntington rats (Kells et al 2004) significantly improves neuronal regeneration. One time injection of 50 μg BDNF could successfully improve the morphology and rescue the electrophysiological properties of injured optic nerve in rabbits.…”

Effects of eugenol on granule cell dispersion in a mouse model of temporal lobe epilepsy

“…S1). Rapamycin [RA; 10 mg/kg (Jeon et al, 2015); LC Laboratories, Woburn, MA, USA], which was diluted in a vehicle solution (4% ethanol, 5% Tween 80, and 5% PEG 400; Sigma), was used as a positive control for GCD changes mediated by mTORC1 deactivation (Shima et al, 2015).…”

“…GCD was expressed as a percentage of the GCL width on the ipsilateral side compared with that on the contralateral side. For immunohistochemistry, sections were incubated for 48 h at 4 • C with anti-phospho-4E-BP1 (p-4E-BP1, a phosphorylated form of the mTORC1 substrate 4E-BP1; 1:1.000; Cell Signaling, Beverly, MA, USA), which indicates mTORC1 activation (Jeon et al, 2015). Sections were then incubated with a suitable biotinylated secondary antibody and processed with an avidin-biotin complex kit (Vector Laboratories, Burlingame, CA, USA).…”

“…The hippocampal DG was isolated from each mouse brain as previously described, with some modifications (Jeon et al, 2015). The tissue was homogenized, and the supernatant was transferred into a fresh tube.…”