Neuroprotective Effect of NO-Delivery Dinitrosyl Iron Complexes (DNICs) on Amyloid Pathology in the Alzheimer's Disease Cell Model.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by cognitive impairment, memory loss, and behavioral deficits. ß-amyloid1-42 (Aß1-42) aggregation is a significant cause of the pathogenesis in AD. Despite the numerous types of research, the current treatment efficacy remains insufficient. Hence, a novel therapeutic strategy is required. Nitric oxide (NO) is a multifunctional gaseous molecule. NO displays a neuroprotective role in the central nervous system by inhibiting the Aß aggregation and rescuing memory and learning deficit through the NO signaling pathway. Targeting the NO pathway might be a therapeutic option; however, NO has a limited half-life under the biological system. To address this issue, a biomimetic dinitrosyl iron complex [(NO)2Fe(µ-SCH2CH2COOH)2Fe(NO)2] (DNIC-COOH) that could stably deliver NO was explored in the current study. To determine whether DNIC-COOH exerts anti-AD efficacy, DNIC-COOH was added to neuron-like cells and primary cortical neurons along with Aß1-42. This study found that DNIC-COOH protected neuronal cells from Aß-induced cytotoxicity, potentiated neuronal functions, and facilitated Aß1-42 degradation through the NO-sGC-cGMP-AKT-GSK3ß-CREB/MMP-9 pathway.

Erinacine S from Hericium erinaceus mycelium promotes neuronal regeneration by inducing neurosteroids accumulation.

Erinacines derived from Hericium erinaceus have been shown to possess various health benefits including neuroprotective effect against neurodegenerative diseases, yet the underlying mechanism remains unknown. Here we found that erinacine S enhances neurite outgrowth in a cell autonomous fashion. It promotes post-injury axon regeneration of PNS neurons and enhances regeneration on inhibitory substrates of CNS neurons. Using RNA-seq and bioinformatic analyses, erinacine S was found to cause the accumulation of neurosteroids in neurons. ELISA and neurosteroidogenesis inhibitor assays were performed to validate this effect. This research uncovers a previously unknown effect of erinacine S on raising the level of neurosteroids.