Comparison of the Effects of Curcumin and RG108 on NGF-Induced PC-12 Adh Cell Differentiation and Neurite Outgrowth

Abstract

DNA methyltransferases (DNMTs) are promising epigenetic targets for the development of novel drugs, especially for neurodegenerative disorders. In recent years, there has been increased interest in small molecules that can cross the blood-brain barrier for the treatment of neurodegenerative diseases. Therefore, comparing the neuronal differentiative effects of a natural compound curcumin and a synthetic small molecule RG108 was the aim of this study. The effects of curcumin and RG108 on neuronal differentiation and neurite outgrowth were investigated in the PC-12 Adh cell line. First, a nontoxic concentration was determined to be 100 nM with WST-1 assay. Subsequently, cells were treated with 100 nM curcumin and RG108 alone or in combination with 50 nM nerve growth factor (NGF). Cell differentiations were evaluated by a real-time cell analyzer system. Neurite outgrowth was determined and morphologically shown by immunofluorescence staining with anti-beta III tubulin antibody on PC-12 Adh cells. Also, growth-associated protein-43 (GAP-43) and β-tubulin III mRNA expression levels, associated with neurite outgrowth promotion, were determined with real-time polymerase chain reaction (RT-PCR). According to our results, 100 nM curcumin and RG108 significantly induced neurite outgrowth of PC-12 Adh cells with 50 nM NGF. Curcumin + NGF combination further increased cell differentiations and total neurite lengths more than curcumin alone and RG108 + NGF combination groups. Strikingly, curcumin and NGF combination upregulated GAP-43 and β-tubulin mRNA expression levels excessively. In conclusion, curcumin was found to be more effective than RG108 on neuronal differentiation and neurite outgrowth of PC-12 Adh cells in a combination with NGF. Therefore, natural DNMT1 inhibitors, such as curcumin, can be a novel approach for the neurodegenerative disorders treatment.

Therapeutic Potential of Vitamin D and Curcumin in an In Vitro Model of Alzheimer Disease

“…36 Curcumin has also shown to initiate proliferation and health of neurite growth and synaptic activity. 37…”

“…36 Curcumin has also shown to initiate proliferation and health of neurite growth and synaptic activity. 37 Although the role of Aβ 1-42 as a potential causative agent in the pathophysiology of AD has been documented extensively, the exact molecular mechanisms and their biochemical effect on the brain tissues are not very clear. The in-vitro treatment of primary neuronal cultures described here tried to elicit the direct effect of Aβ 1-42 on the primary neuronal cells and find out if vitamin D3 or curcumin could be used as natural therapy for its treatment.…”

Can Brain Health Be Supported by Vitamin D-Based Supplements? A Critical Review

“…During aging, there is a significant loss of NGF; however, this effect was neutralized in the presence of vitamin D3 or curcumin. Earlier studies have indicated the role of vitamin D3 in the regulation and secretion of NGF and GDNF [ 195 ]. Curcumin has also been shown to initiate proliferation and improve the health of neurite growth and synaptic activity [ 196 ].…”

A Novel Approach via Surface Modification of Degradable Polymers With Adhesive DOPA-IGF-1 for Neural Tissue Engineering

“…It was because PC12 cells are well-known to be highly responsive to NGF in the neuritogenesis and differentiation. 30 Cells were maintained in RPMI 1640 (ATCC Cell Biology, Manassas, VA) containing 10% heatinactivated equine serum (SH30074; Hyclone, South Logan, UT) and 5% fetal bovine serum, at 37 C in the incubator with 5% CO 2 and 95% humidity. To observe neurite outgrowth, PC12 cells were plated at 10,000 cells per well of a 24 well plate.…”