title: Inhibitory effects of compounds from Phyllanthus amarus on nitric oxide production, lymphocyte proliferation, and cytokine release from phagocytes.
abstract: Standardized extract of Phyllanthus amarus has previously been shown to have a strong inhibitory effect on phagocytic activity of human neutrophils. The current study was carried out to evaluate the effects of constituents of the extract of P. amarus on nitric oxide (NO) production as well as lymphocyte proliferation and cytokine release from phagocytes. Three compounds, ethyl 8-hydroxy-8-methyl-tridecanoate, 7β,19α dihydroxy-urs-12-ene, and 1,7,8-trihydroxy-2-naphtaldehyde, together with seven known compounds were isolated from the whole plant of P. amarus. The isolated compounds and reference standards, ie, gallic acid, ellagic acid, corilagin, and geraniin, which were quantitatively analyzed in the extracts, were evaluated for their effects on immune cells. Among the compounds tested, the lignans, especially phyltetralin and phyllanthin, showed strong inhibition on lymphocyte proliferation with half maximal inhibitory concentration (IC50) values of 1.07 μM and 1.82 μM, respectively. Ethyl 8-hydroxy-8-methyl-tridecanoate and 1,7,8-trihydroxy-2-naphtaldehyde exhibited strong inhibition on nitric oxide production with IC50 values of 0.91 μM and 1.07 μM, respectively. Of all the compounds, corilagin was the strongest inhibitor of tumor necrosis factor-α release with an IC50 value of 7.39 μM, whereas geraniin depicted the strongest inhibitory activity on interleukin-1β release with an IC50 value of 16.41 μM. The compounds constituting the extract of P. amarus were able to inhibit the innate immune response of phagocytes at different steps.
authors.affiliation: Drug and Herbal Research Center, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia; Falkultas Farmasi, Universitas Sumatera Utara, USU-Kampus, Medan, Indonesia.
authors.lastname: Yuandani
authors.affiliation: Drug and Herbal Research Center, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia.
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Jantan
authors.affiliation: Drug and Herbal Research Center, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia.
authors.forename: Menaga
authors.initials: M
authors.lastname: Ilangkovan
authors.affiliation: Drug and Herbal Research Center, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia.
authors.forename: Khairana
authors.initials: K
authors.lastname: Husain
authors.affiliation: Biomedical Science Programme, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia.
authors.forename: Kok Meng
authors.initials: KM
authors.lastname: Chan
mesh_terms: D006801:Humans; D053583:Interleukin-1beta / Q000037:antagonists & inhibitors* / Q000737:chemistry; D017705:Lignans / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000737:chemistry / Q000187:drug effects*; D009569:Nitric Oxide / Q000737:chemistry*; D010586:Phagocytes / Q000187:drug effects*; D029803:Phyllanthus / Q000737:chemistry*; D010936:Plant Extracts / Q000494:pharmacology; D014315:Triterpenes / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: C000618633:1,7,8-trihydroxy-2-naphtaldehyde; C000618632:7beta,19alpha dihydroxy-urs-12-ene; D053583:Interleukin-1beta; D017705:Lignans; D010936:Plant Extracts; D014315:Triterpenes; C000618634:ethyl 8-hydroxy-8-methyl-tridecanoate; D009569:Nitric Oxide; C517985:phyllanthin
keywords: 1,7,8-trihydroxy-2-naphtaldehyde; 7β,19α-dihydroxy-urs-12-ene; Phyllanthus amarus (Euphorbiaceae); hypophyllanthin; immunosuppressive effects; phyllanthin