Lignans anti-inflammatory activity

Phenolics and their functional derivatives are widely found throughout the plant kingdom. One defining characteristic of these compounds is that their aromatic ring usually contains at least one hydroxyl substituent. In a broad sense, phenolics, which are classified according to their structural skeleton, are basically derivatives from simple phenols and phenolic acids, phenylpropanoids including coumarins and lignans, flavonoids and related compounds, and stilbenes. Some of these compounds which show anti-inflammatory activity are reviewed in this section. 

Five lignans isolated from the heartwood of T. baccata L. growing in Turkey were evaluated for their anti-inflammatory and antinociceptive activities in vivo. All of the compounds were shown to possess significant antinociceptive activities against p-bcnzoquinone-induccd abdominal contractions and significantly inhibited carrageenan-induced hind paw edema in mice [100]. 

From the methanol extract of Haplophyllum hispanicum (Rutaceae) two topical anti-inflammatory aryl naphthalide lignans were isolated and identified as diphyllin acetyl apioside and tuberculatin [284], The methanol extract was only active against the acute TPA-induced ear edema, whereas it was not active against the chronic inflammation induced by TPA or oxazolone-induced contact-delayed hypersensitivity in mouse ears. Diphyllin acetyl apioside was the most active of the isolated compounds on the acute TPA, with an ID50 of 0.27 pmol/ear, whereas tuberculatin gave an ID50 of 1.23 pmol/ear. 

Baba et al. [286,287] studied the structure-activity relationships of some lignans as anti-inflammatory agents and in a second paper gave detailed information on the bone resorption inhibitory effects of these compounds. Chemical modification of the potent bone resorption inhibitor justicidin was performed and various naphthalene lactones, quinoline lactones and... 

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