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Observations placeholder

Limonene, citrus fruits and rheumatoid arthritis



Type of Spiritual Experience


Limonene is a colourless liquid hydrocarbon classified as a cyclic terpene. The more common D-isomer possesses a strong smell of oranges. Limonene takes its name from the lemon, as the rind of the lemon, like other citrus fruits, contains considerable amounts of this compound, which contributes to their odour.

Limonene is an adenosine agonist as the observation shows and has the capability to heal a number of inflammatory problems – not least those related to arthritis

A description of the experience

Biochem Biophys Res Commun. 2011 Jan 7;404(1):345-8. doi: 10.1016/j.bbrc.2010.11.121. Epub 2010 Dec 4. Limonene, a natural cyclic terpene, is an agonistic ligand for adenosine A(2A) receptors. Park HM, Lee JH, Yaoyao J, Jun HJ, Lee SJ. Division of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Korea University, Seoul, 136-713, South Korea.

Limonene is a major aromatic compound in essential oils extracted from citrus rind. The application of limonene, especially in aromatherapy, has expanded significantly, but its potential effects on cellular metabolism have been elusive.

We found that limonene directly binds to the adenosine A(2A) receptor, which may induce sedative effects.

Results from an in vitro radioligand binding assay showed that limonene exhibits selective affinity to A(2A) receptors. In addition, limonene increased cytosolic cAMP concentration and induced activation of protein kinase A and phosphorylation of cAMP-response element-binding protein in Chinese hamster ovary cells transfected with the human adenosine A(2A) receptor gene.

Limonene also increased cytosolic calcium concentration, which can be achieved by the activation of adenosine A(2A) receptors. These findings suggest that limonene can act as a ligand and an agonist for adenosine A(2A) receptors.

Copyright © 2010 Elsevier Inc. All rights reserved.

PMID: 21134357

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