Akram, M.; Daniyal, M.; Gorelick, J.

Plants containing natural products have been used worldwide in traditional medicine since antiquity and are a source of potential and powerful drugs. The potential of higher plants as a source for new drugs is still largely unexplored, and among the estimated 250,000–500,000 plant species, only a small fraction has been submitted to biological or pharmacological screening. Medicinal plants and their isolated compounds are utilized worldwide in traditional medicine for the treatment of various inflammatory conditions, and the therapeutic potential of traditionally used plants and their constituents is currently a target of research in the pursuit of novel antiinflammatory drugs. Inflammation is the normal reaction of animal living tissue to all forms of injury. It is a dynamic and complex tissue reaction provoked by cellular injury, which involves a cascade of biochemical events. Although inflammation is a protective measure taken by the organism to eliminate the injurious stimuli, uncontrolled inflammation can lead to damage. For this reason, inflammation is closely regulated by the body or with the aid of administrated antiinflammatory compounds. The search for alternative substances capable of interfering with the inflammatory process has become a significant issue in scientific research, especially with reference to the search for natural substances and the reduction of negative side effects of conventional medications. Although dozens of plant species were reported in ethnomedicine for the treatment of inflammation, only a fraction of these were confirmed in antiinflammatory studies. This review evaluates the current state of knowledge concerning promising antiinflammatory activity of herbal plants and plant substances that have been tested in inflammatory models using modern scientific systems. © 2018 Elsevier Inc.