Dataset Information

Identification of natural products with neuronal and metabolic benefits through autophagy induction.

ABSTRACT: Autophagy is a housekeeping lysosomal degradation pathway important for cellular survival, homeostasis and function. Various disease models have shown that upregulation of autophagy may be beneficial to combat disease pathogenesis. However, despite several recently reported small-molecule screens for synthetic autophagy inducers, natural chemicals of diverse structures and functions have not been included in the synthetic libraries, and characterization of their roles in autophagy has been lacking. To discover novel autophagy-regulating compounds and study their therapeutic mechanisms, we used analytic chemistry approaches to isolate natural phytochemicals from a reservoir of medicinal plants used in traditional remedies. From this pilot plant metabolite library, we identified several novel autophagy-inducing phytochemicals, including Rg2. Rg2 is a steroid glycoside chemical that activates autophagy in an AMPK-ULK1-dependent and MTOR-independent manner. Induction of autophagy by Rg2 enhances the clearance of protein aggregates in a cell-based model, improves cognitive behaviors in a mouse model of Alzheimer disease, and prevents high-fat diet-induced insulin resistance. Thus, we discovered a series of autophagy-inducing phytochemicals from medicinal plants, and found that one of the compounds Rg2 mediates metabolic and neurotrophic effects dependent on activation of the autophagy pathway. These findings may help explain how medicinal plants exert the therapeutic functions against metabolic diseases.

SUBMITTER: Fan Y

PROVIDER: S-EPMC5240827 | biostudies-other | 2017 Jan

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Identification of natural products with neuronal and metabolic benefits through autophagy induction.

Fan Yuying Y Wang Nan N Rocchi Altea A Zhang Weiran W Vassar Robert R Zhou Yifa Y He Congcong C

Autophagy 20161028 1

Autophagy is a housekeeping lysosomal degradation pathway important for cellular survival, homeostasis and function. Various disease models have shown that upregulation of autophagy may be beneficial to combat disease pathogenesis. However, despite several recently reported small-molecule screens for synthetic autophagy inducers, natural chemicals of diverse structures and functions have not been included in the synthetic libraries, and characterization of their roles in autophagy has been lacki ...[more]

PMID: 27791467

Similar Datasets

Project description:Machado-Joseph disease (MJD) is a fatal neurodegenerative disease caused by expansion of the trinucleotide repeat region within the ATXN3/MJD gene. Mutation of ATXN3 causes formation of neurotoxic ataxin-3 protein aggregates, neurodegeneration and motor deficits. Here we investigated the therapeutic potential and mechanistic activity of sodium butyrate (SB), the sodium salt of butyric acid, a metabolite naturally produced by gut microbiota, on cultured SH-SY5Y cells and transgenic zebrafish expressing human ataxin-3 containing 84 glutamine (Q) residues to model MJD. MJD SH-SY5Y cells were found to contain ataxin-3 oligomeric species and protein aggregates. Treatment with SB increased activity of the autophagy protein quality control pathway in the MJD cells, decreased presence of ataxin-3 aggregates and presence of ataxin-3 oligomers in an autophagy-dependent manner. Treatment with SB was also beneficial in vivo, improving swimming performance, increasing autophagy activity and decreasing presence of insoluble ataxin-3 protein species in the transgenic MJD zebrafish. Co-treating the MJD zebrafish with SB and chloroquine, an autophagy inhibitor, prevented the beneficial effects of SB on the zebrafish swimming, suggesting that the improved swimming performance was autophagy-dependent. To identify mechanism of the induction of autophagy by SB, we performed proteomic analysis of protein lysates from the SB treated and untreated MJD SH-SY5Y cells. We found that SB treatment had increased activity of Protein Kinase A and AMPK signaling. Immunoblot analysis confirmed that SB treatment had increased levels of acetylated FOXO1 protein. Further, co-treatment with an inhibitor of FOXO1 transcriptional activity (AS1842856) prevented the increase in autophagosome formation (LC3II/I) usually produced by SB treatment. Together our findings indicate that treatment with SB can increase activity of the autophagy pathway through a FOXO1-dependent process and that this has beneficial effects in vitro and in vivo. We propose that treatment with sodium butyrate warrants further investigation for the treatment of neurodegenerative diseases underpinned by proteinopathy mechanisms, including MJD.

Dataset Information

Identification of natural products with neuronal and metabolic benefits through autophagy induction.

Publications

Identification of natural products with neuronal and metabolic benefits through autophagy induction.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets