Inflammation is a general term used to describe various
pathological processes with diverse causes that can include
infection,
trauma, or an autoimmune response. Due to its many causes, the inflammatory response involves multiple and varied mediators, including vasoactive
amines,
free radicals, and both lipidic and peptidic mediators. Medicinal plants and the compounds derived from them are a good source of new and specific inhibitors of the inflammatory process. The past decade has witnessed many important discoveries in this field, with new findings challenging the more traditional views of pharmacologists. Various studies, for example, have demonstrated the positive effects of plant-derived phenolics, which act as
anti-oxidants,
free radical scavengers, and inhibitors of
nitric-oxide synthase,
cyclooxygenase, and
lipoxygenase. The anti-inflammatory activity of
chalcones has been correlated with the induction of
heme oxygenase-1 while phlorotannins have been found to inhibit
matrix metalloproteinase, which is implicated in
arthritis, chronic
inflammation, and wrinkle formation.
Sesquiterpene lactones have been studied as inhibitors of
NF-kappaB activity and the relationship between their chemical structure and pharmacological activity has been clearly established. Recently,
cucurbitacins have been described as inhibitors of JAK -STAT and NF-AT functions related to
inflammation; they were also found to induce apoptosis of cells involved in the inflammatory response. This review focuses mainly on the effects of natural products on
transcription factors, which are the most promising targets for designing new active drugs against
inflammation and
cancer.