Current Immunology Reviews (Discontinued) - Volume 10, Issue 2, 2014

Herbal medicines are a mainstay in most Asian countries and have been used successfully for thousands of years to modulate immune system function. At least thirty herbs and plants fall into this category, with many having been developed for usage as “classic” pharmaceutical agents. This paper will review the discovery (if known), usage and scientific evidence for the biological and chemical activity behind the botanical products commonly used to boost or inhibit immune system function. Issues with production purity, shelf life and effectiveness of each herbal and plant moiety will also be discussed.

COX-2 inhibitors now constitute an important and central component in the treatment of a number of chronic diseases ranging from arthritis and autoimmunity to cancer. Their use is not without side effects, however, and they are unsuitable for patients with a variety of conditions including heart or kidney disease and those who are pregnant. In contrast, herbal medicines have been used successfully for thousands of years to modulate immune system function. Several have demonstrated COX-2 inhibitory activity and may therefore have potential for development into classical pharmaceutical agents. This paper will explain the importance of COX-2 activity and the related entity NF-ΚB in inducing inflammation, review the scientific evidence for herbs with COX-2 activity, and identify the active phytochemicals involved. Finally potential paths to develop agents from these herbs will be discussed.

Herbal products have a long history of general usage in traditional Chinese and other complementary medicine protocols. They are used in the treatment of a variety of conditions most importantly stimulation or inhibition of the immune system. In this regard, of particular importance are Astragalus membranaceous, Panax ginseng and Echinacea purpurea; the latter two having found favor across the globe and in common usage by millions of individuals hoping to improve cancer symptoms (P. ginseng) and fight colds and influenza (E. purpurea). Hundreds of papers have been written about these three phytochemicals, but the most rigorous and widely cited was written by Block and Mead in 2003, who underlined the weaknesses in the scientific rigor associated with evaluating these medicines as well as suggesting strategies to move forward. Using Block and Mead as a platform, this review aims to evaluate whether our knowledge base has improved subsequently.

Garlic is widely consumed as both a food additive and medicine around the globe and has been for over 5,000 years. Immunomodulatory substances in garlic abound and include alicin, aliin, ajoene and organosulfides, many of which increase in potency as the cloves are aged. Garlic can be used in many forms, each of which takes on different properties depending on the relative phytochemicals within it. The purpose of this mini-review is therefore to first explore the uses of garlic itself, explaining the biochemistry of its individual constituents and then go on to evaluate the literature for appropriate pre-clinical animal and cellular models of efficacy as well as available human clinical trials. Finally, the review will explore possible solutions to standardization of the use of garlic as medicine as well as possible directions in which such research might be developed.

Curcumin is the phytochemical derived from the bulb of the plant Curcuma longa and is the major component of turmeric. The herb has been used for thousands of years, initially to heal wounds but also to treat diverse conditions in traditional Ayurvedic and Asian medicine. More recently it has also been discovered to be capable of inhibiting the proliferation of cancer cells and/or inducing many signalling pathways affecting chronic inflammation including nuclear factor kappa beta (NF-ΚB) and cyclooxygenase-2 enzymes (COX-2). The focus of this monograph is to examine the pre-clinical and clinical data for curcumin as well as its phytochemical components.