Cinnamon polyphenols regulate S100β, sirtuins, and neuroactive proteins in rat C6 glioma cells.
OBJECTIVE
Increasing evidence suggests that cinnamon has many health benefits when used in herbal medicine and as a dietary ingredient. The aim of this study was to investigate the effects of an aqueous extract of cinnamon, high in type A polyphenols, on molecular targets in rat C6 glioma cells that underlie their protective effects.


METHODS
C6 rat glioma cells were seeded in 35-mm culture dishes or six-well plates, then were incubated with cinnamon polyphenols at doses of 10 and 20 μg/mL for 24 h. The targeting protein expression, secretion, and phosphorylation were evaluated by immunoprecitation/immunoblotting and immunofluorescence imaging.


RESULTS
Cinnamon polyphenols significantly enhanced secretion of S100β, a Ca(2+)-binding protein, and increased intracellular S100β expression after 24 h of incubation, in rat C6 glioma cells. Cinnamon polyphenols also enhanced protein levels of sirtuin 1, 2, and 3, deacetylases important in cell survival, and the tumor suppressor protein, p53, and inhibited the inflammatory factors, tumor necrosis factor alpha, and phospho-p65, a subunit of nuclear factor-κβ. Cinnamon polyphenols also up-regulated levels of phospho-p38, extracellular signal-regulated protein and mitogen-activated protein and kinase-activated protein kinases that may be important for prosurvival functions.


CONCLUSIONS
Our results indicate that the effects of cinnamon polyphenols on upregulating prosurvival proteins, activating mitogen-activated protein kinase pathways, and decreasing proinflammatory cytokines may contribute to their neuroprotective effects.
Diet, Genomics and Immunology Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD, USA; Integrity Nutraceuticals International, Spring Hill, TN, USA. Electronic address: Bolin.Qin@ars.usda.gov.
Bolin
B
Qin
Diet, Genomics and Immunology Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD, USA; Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, USA.
Kiran S
KS
Panickar
Diet, Genomics and Immunology Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD, USA.
Richard A
RA
Anderson
D000818:Animals; D045744:Cell Line, Tumor; D002935:Cinnamomum zeylanicum / Q000737:chemistry*; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D005910:Glioma / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D059808:Polyphenols / Q000494:pharmacology*; D051381:Rats; D064568:S100 Calcium Binding Protein beta Subunit / Q000235:genetics / Q000378:metabolism*; D056564:Sirtuin 1 / Q000235:genetics / Q000378:metabolism*; D056565:Sirtuin 2 / Q000235:genetics / Q000378:metabolism*; D051996:Transcription Factor RelA / Q000235:genetics / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation; D051020:bcl-X Protein / Q000235:genetics / Q000378:metabolism
C494813:Bcl2l1 protein, rat; D016207:Cytokines; D059808:Polyphenols; C498145:Rela protein, rat; D064568:S100 Calcium Binding Protein beta Subunit; C097475:Sirt2 protein, rat; D051996:Transcription Factor RelA; D014409:Tumor Necrosis Factor-alpha; D016159:Tumor Suppressor Protein p53; D051020:bcl-X Protein; D020928:Mitogen-Activated Protein Kinases; C488368:Sirt1 protein, rat; D056564:Sirtuin 1; D056565:Sirtuin 2
Phospho-NF-κB and Bcl-xl; Polyphenols; S100β; Sirtuins; Spice