About Swietenia macrophylla G.King
Swietenia macrophylla, with the common names mahogany, Honduran mahogany, Honduras mahogany, and big-leaf mahogany, is a plant species in the Meliaceae family. It is one of three species in the genus Swietenia that produce genuine mahogany timber; the other two species are Swietenia mahagoni and Swietenia humilis. This species is native to South America, Mexico, and Central America. It has become naturalized in the Philippines, Singapore, Malaysia, and Hawaii, and is cultivated in plantations and as windbreaks in other regions. S. macrophylla has been the subject of scientific study for a range of biological activities. Researchers have detailed the mechanism behind its apoptotic effect on the HCT116 human cancer cell line. After solvent extraction and fractionation of S. macrophylla seeds, the resulting ethyl acetate fraction (SMEAF) was tested further for neuroprotective activity and acute toxicity effects. Testing of various purified compounds from this species found that they have potent PPARγ binding activity, which may be capable of stimulating glucose uptake in muscle cells. SMEAF was examined for anti-inflammatory properties using lipopolysaccharide (LPS)-induced BV-2 microglia. In this model, SMEAF significantly reduced the LPS-induced production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumour necrosis factor-α (TNF-α), and interleukin-6 (IL-6). SMEAF inhibited the nuclear translocation of nuclear factor-kappa B (NF-κB) by reducing IκBα phosphorylation. It also markedly suppressed phosphorylation of Akt, p38 mitogen-activated protein kinase (MAPK), and extracellular signal-regulated kinase 1/2 (ERK1/2) in LPS-induced BV-2 cells. When cells were treated with specific inhibitors for Akt, NF-κB, p38, and ERK1/2, iNOS and COX-2 protein expression was reduced. These findings indicate that SMEAF exerts anti-inflammatory activity in BV-2 cells by modifying LPS-induced pro-inflammatory mediator production, through inhibiting the activation of Akt-dependent NF-κB, p38 MAPK, and ERK1/2. These results support the potential use of S. macrophylla as a nutraceutical for intervention against neurodegenerative and neuroinflammatory disorders. There are also unsubstantiated claims that the species can improve blood circulation and skin condition, and treat erectile dysfunction. There have been documented reports of liver injury (hepatotoxicity) after consuming mahogany seeds, both eaten raw and consumed as ground raw seeds packed into capsules. The severity of reported liver damage varies, and there is also one reported case of kidney injury and polyarthralgia linked to consumption. In most cases, liver function recovered after people stopped consuming the seeds. The exact mechanism behind these adverse events is currently unknown. These cases are the first reported links between S. macrophylla seeds and liver injury; the issues may also be linked to overdosage or consumption of contaminated raw seeds, a possibility that has never been thoroughly investigated. Results from acute oral toxicity studies of S. macrophylla seeds indicate that human consumption is safe when the dose is less than 325 mg per kg of body weight. The standard dose of S. macrophylla prescribed in Malaysian folk medicine is one seed per day.
