African plants with in vitro anti-inflammatory activities: A review

Inflammation is a normal response of the body to injury or foreign insult. Inflammation has been known to humankind since the dawn of history as it is characterized by pain. Humans started the search for various means, including plants, to control and manage inflammation since time immemorial. Hence, it is not surprising that most current research on anti-inflammatory drug discovery from plants worldwide followed ethnobotanical leads. This review provides an overview of African plants that demonstrated promising anti-inflammatory activity in in vitro studies. The review also includes information on natural products with anti-inflammatory activity isolated from higher African plants. The information was collected from different sources including books, theses, reports and electronic scientific search engines such as Scopus, Science Direct, Medweb and Google Scholar. Terms such as plant, plant extracts, inflammation and anti-inflammatory were used in combination with each of the African countries. Extracts from African plants and compounds isolated there from have shown anti-inflammatory effects in a set of in vitro anti-inflammatory models. These models included target inflammatory mediators such as cyclooxygenases, lipoxygenases, inducible nitric oxide synthase, xanthine oxidase and the pro-inflammatory mediators such as tumor necrosis factor-alpha and interleukins. This review highlights the potential of African flora in contributing to anti-inflammatory drug discovery. Many plant species had anti-inflammatory activity in vitro. However, further studies are needed such as isolation of bioactive compounds, confirmation of the in vitro activities in animal models and the severity of side effects or lack thereof need to be investigated further. (C) 2019 SAAB. Published by Elsevier B.V. All rights reserved.