Introduction: The genus Cinnamomum (cinnamon) is one of the well-known aromatic spices throughout the world with numerous medicinal applications. Several useful pharmacological properties of cinnamon have been evaluated such as antioxidant, anti-inflammatory, anti-diabetic, anticancer, cardiovascular-disease-lowering, neurological disorders improving, etc.This review critically evaluated studies regarding the molecular mechanisms of antioxidant and anti-inflammatory properties of cinnamon species.
Methods: Using three online literature databases (PubMed, Scopus, Science Direct), we identified studies describing the antioxidant and anti-inflammatory properties of cinnamon species. A literature search was carried out using a combination of keywords such as (“Cinnamomum,”) AND (“antioxidant” OR “anti-inflammatory”) or other related words including. In this review, we evaluated new findings regarding the molecular mechanisms of antioxidant and anti-inflammatory effects of Cinnamomum species published from 2005 until December 2022. 38 papers were selected to describe the antioxidant and anti-inflammatory properties of cinnamon species.
 Results: cinnamon species possess antioxidant effects via ROS, MDA, NO, and GSH depletion reduction, MPO activity decrease, and growth of SOD and CAT. Additionally, suppression of caspase-3, and caspase-9 activity and upregulating the expression of bcl-2 determine the anti-apoptotic effects of cinnamon. The anti-inflammatory effects of them are mainly related to a reduction of TNF-α, IL-1β, IL-6, IL-18, IL-10, iNOS, MCP-1, and COX-2 and inhibition the activation of NF-κB, ERK1/2, p38 and JNK.
Conclusion: This review highlighted antioxidant and anti-inflammatory effects of genus cinnamon and can provide a suitable basis for further pharmacologic surveys and efficient clinical research about cinnamon to obtain new evidence on human health.