Cinnamic acid is also found in the propolis of honey which is used by traditional medicine for its biological properties. The rather complex chemical composition of propolis also includes phenolics, including cinnamic acid which is considered to be capable of immunomodulating action depending on its concentration, inhibiting the production of chitochines (1).
With experiments on rats, this acid gave positive effects on the containment of obesity and against hypertensive effects, through the inhibition of lipid digestive enzymes and the angiotensin converting enzyme (2) and exerts an anti-diabetic activity improving glucose tolerance and stimulating insulin secretion in vitro (3).
Other studies
Design and synthesis of the novel oleanolic acid-cinnamic acid ester derivatives and glycyrrhetinic acid-cinnamic acid ester derivatives with cytotoxic properties.
Wang R, Yang W, Fan Y, Dehaen W, Li Y, Li H, Wang W, Zheng Q, Huai Q.
Bioorg Chem. 2019 Apr 27;88:102951. doi: 10.1016/j.bioorg.2019.102951
Growth inhibition of human breast and prostate cancer cells by cinnamic acid derivatives and their mechanism of action.
Imai M, Yokoe H, Tsubuki M, Takahashi N.
Biol Pharm Bull. 2019 Apr 12. doi: 10.1248/bpb.b18-01002.
Novel Cinnamic Acid Derivatives as Potential PPARδ Agonists for Metabolic Syndrome: Design, Synthesis, Evaluation and Docking Studies.
Chauhan A, Grewal AS, Pandita D, Lather V.
Curr Drug Discov Technol. 2019 Mar 14. doi: 10.2174/1570163816666190314124543.
Morphine Dependence is Attenuated by Treatment of 3,4,5-Trimethoxy Cinnamic Acid in Mice and Rats.
Moon S, Kang S, Shin H, Yayeh T, Sur B, Oh S.
Neurochem Res. 2019 Apr;44(4):874-883. doi: 10.1007/s11064-019-02720-9.
References__________________________________________________________________________________
(1) Cinnamic Acid Is Partially Involved in Propolis Immunomodulatory Action on Human Monocytes
Bruno José Conti, Michelle Cristiane Búfalo, Marjorie de Assis Golim, Vassya Bankova, José Maurício Sforcin
Evid Based Complement Alternat Med. 2013
(2) Anti-obesity and cardioprotective effects of cinnamic acid in high fat diet- induced obese rats.
Mnafgui K, Derbali A, Sayadi S, Gharsallah N, Elfeki A, Allouche N.
J Food Sci Technol. 2015 Jul;52(7):4369-77. doi: 10.1007/s13197-014-1488-2. Epub 2014 Jul 31.
(3) Cinnamic acid exerts anti-diabetic activity by improving glucose tolerance in vivo and by stimulating insulin secretion in vitro.
Hafizur RM, Hameed A, Shukrana M, Raza SA, Chishti S, Kabir N, Siddiqui RA.
Phytomedicine. 2015 Feb 15;22(2):297-300. doi: 10.1016/j.phymed.2015.01.003. Epub 2015 Jan 19.
Cinnamic Acid 
