Hydro-ethanolic extract of cashew tree (Anacardium occidentale) nut and its principal compound, anacardic acid, stimulate glucose uptake in C2C12 muscle cells.
METHODS
Products of cashew tree (Anacardium occidentale) are used in traditional medicine for various ailments, including diabetes.


RESULTS
The anti-diabetic properties of cashew plant parts were studied using differentiated C2C12 myoblasts (myotubes) and rat liver mitochondria. Hydroethanolic extract of cashew seed (CSE) and its active component, anacardic acid (AA), stimulated glucose transport into C2C12 myotubes in a concentration-dependent manner. Extracts of other parts (leaves, bark and apple) of cashew plant were inactive. Significant synergistic effect on glucose uptake with insulin was noticed at 100 μg/mL CSE. CSE and AA caused activation of adenosine monophosphate-activated protein kinase in C2C12 myotubes after 6 h of incubation. No significant effect was noticed on Akt and insulin receptor phosphorylation. Both CSE and AA exerted significant uncoupling of succinate-stimulated respiration in rat liver mitochondria.


CONCLUSIONS
Activation of adenosine monophosphate-activated protein kinase by CSE and AA likely increases plasma membrane glucose transporters, resulting in elevated glucose uptake. In addition, the dysfunction of mitochondrial oxidative phosphorylation may enhance glycolysis and contribute to increased glucose uptake. These results collectively suggest that CSE may be a potential anti-diabetic nutraceutical.
Tedong
Leonard
L
Natural Health Products and Metabolic Diseases Laboratory, Department of Pharmacology and Montreal Diabetes Research Center, Université de Montréal, Montréal, Québec, Canada.
Madiraju
Padma
P
Martineau
Louis C
LC
Vallerand
Diane
D
Arnason
John T
JT
Desire
Dzeufiet D P
DD
Lavoie
Louis
L
Kamtchouing
Pierre
P
Haddad
Pierre S
PS
D048729:Anacardic Acids / Q000494:pharmacology*; D031021:Anacardium / Q000737:chemistry*; D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D005947:Glucose / Q000378:metabolism*; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007328:Insulin / Q000378:metabolism; D008297:Male; D051379:Mice; D008930:Mitochondria, Liver / Q000187:drug effects; D032342:Muscle Cells / Q000166:cytology / Q000378:metabolism; D018485:Muscle Fibers, Skeletal / Q000166:cytology*; D009754:Nuts / Q000737:chemistry; D010085:Oxidative Phosphorylation; D010936:Plant Extracts / Q000494:pharmacology; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011972:Receptor, Insulin / Q000378:metabolism; D012639:Seeds / Q000737:chemistry*
D048729:Anacardic Acids; D007004:Hypoglycemic Agents; D007328:Insulin; D010936:Plant Extracts; C088115:anacardic acid; D011972:Receptor, Insulin; D051057:Proto-Oncogene Proteins c-akt; D005947:Glucose