Abstract
There is considerable interest in the utilisation of plants against inflammation.
Over 50 species of the plant family Amaryllidaceae are known for such usage in traditional
medicine. This review was undertaken to identify the chemical principles responsible
for these anti-inflammatory effects. It describes the findings from in vitro, in vivo and in silico studies, as well as the probes made on the mechanisms of action. The literature search
returned over 600 hits, of which around 130 were chosen for their relevance to the
text. Over 140 compounds have thus far been screened for anti-inflammatory effects.
These were mostly isoquinoline alkaloids but also included other classes of secondary
metabolites such as chromones, flavonoids and triterpenoids. In vitro studies were carried out in mononuclear cells such as lymphocytes, monocytes, neutrophils
and macrophages, against which no serious side effects were observed. The constituents
were also effective
against inflammation induced by physical and chemical stimuli in a variety of murine
test subjects. Chief among the compounds were the isoquinoline alkaloids lycorine
and narciclasine, which displayed potent effects against pain, swelling, asthma and
arthritis, amongst others. From a mechanistic perspective, several of the compounds
were shown to mediate in inflammatory pathways, notably via the modulation of both
pro-inflammatory (such as NF-κB, TNF-α and IL-1) and anti-inflammatory (such as IL-10 and TGF-β) factors. Useful insights also emerged from active-site docking studies of some of
the compounds. The Amaryllidaceae affords a rich and diverse platform for the discovery
of potential anti-inflammatory drugs.
Keywords
alkaloid - Amaryllidaceae - anti-inflammatory - drug discovery - medicinal plant
