Pharmacological effects of elenoside, an arylnaphthalene lignan

Targeted Isolation of Anti-inflammatory Lignans from Justicia aequilabris by Molecular Networking Approach

Herein, the isolation of secondary metabolites from the aerial parts of Justicia aequilabris guided by HPLC-MSⁿ and molecular networking analyses is reported. Twenty-two known compounds were dereplicated. Three new lignans (aequilabrines A-C (1-3)) and three known compounds (lariciresinol-4'-O-β-glucose (4), roseoside (5), and allantoin (6)) were obtained. The anti-inflammatory activity of compounds 1-3 was evaluated in vitro by inhibiting the nitric oxide production (NO) and pro-inflammatory activity on the cytokine IL-1β. Compounds 2 and 3 showed significant inhibitory activity against NO production, with IC₅₀ values of 9.1 and 7.3 μM, respectively. The maximum inhibition of IL-1β production was 23.5% (1), 27.3% (2), and 32.5% (3).

Toxicity and neuropharmacological effects of elenine

Elenine is the aglycone of elenoside, a cytotoxic arylnaphthalene lignan (NSC 644013-W/1) derived from Justicia hyssopifolia. (Family: Acanthaceae). Elenoside is a β-D-glucoside, with a similar chemical structure to etoposide, exhibiting central depressant activity. In the present study, elenine was given to mice and rats at doses of 10, 20, and 40 mg/kg. Acute toxicity (24 h) and general behaviour in mice was studied as well as its effects on muscular relaxant activity, locomotor activity (Varimex test), and the open-field test and were compared with 10 mg/kg of chlorpromazine. Elenine produced a reduction in the permanence time in muscular relaxant activity (traction test). Spontaneous activity was lower in the Varimex test. The ambulation and rearing were lower compared with the control group, and an increase in boluses was observed in the open-field test. Thus, it can be concluded that elenine has central sedative effects at lower doses than those used with elenoside and has a possible application in conditions of anxiety.

Laxanol, a new 2,5-Diaryl-3,4-Dihydroxymethyltetrahydrofuran Type Lignan from Justicia Laxa

The unsymmetrical 2,5-diaryl-tetrahydrofuran type lignan, 2-(3′-methoxy-4′-hydroxyphenyl)-3,4-dihydroxymethyl-5-(3″-methoxy-5″-hydroxyphenyl)-tetrahydrofuran, laxanol (1), was obtained from Justicia laxa via high-throughput natural product chemistry methods as a mass-limited sample and its structure was elucidated by capillary scale NMR and HR-/LR-ESIMS analyses.

Elenoside increases intestinal motility

AIM: To study the effects of elenoside, an arylnaph-thalene lignan from Justicia hyssopifolia, on gastro-intestinal motility in vivo and in vitro in rats.

METHODS: Routine in vivo experimental assessments were catharsis index, water percentage of boluses, intestinal transit, and codeine antagonism. The groups included were vehicle control (propylene glycol-ethanol-plant oil-tween 80), elenoside (i.p. 25 and 50 mg/kg), cisapride (i.p. 10 mg/kg), and codeine phosphate (intragastric route, 50 mg/kg). In vitro approaches used isolated rat intestinal tissues (duodenum, jejunum, and ileum). The effects of elenoside at concentrations of 3.2 x 10^-4, 6.4 x 10^-4 and 1.2 x 10^-3 mol/L, and cisapride at 10^-6 mol/L were investigated.

RESULTS: Elenoside in vivo produced an increase in the catharsis index and water percentage of boluses and in the percentage of distance traveled by a suspension of activated charcoal. Codeine phosphate antagonized the effect of 25 mg/kg of elenoside. In vitro, elenoside in duodenum, jejunum and ileum produced an initial decrease in the contraction force followed by an increase. Elenoside resulted in decreased intestinal frequency in duodenum, jejunum, and ileum. The in vitro and in vivo effects of elenoside were similar to those produced by cisapride.

CONCLUSION: Elenoside is a lignan with an action similar to that of purgative and prokinetics drugs. Elenoside, could be an alternative to cisapride in treatment of gastrointestinal diseases as well as a preventive therapy for the undesirable gastrointestinal effects produced by opioids used for mild to moderate pain.

An update on bioactive plant lignans

Lignans are a class of secondary plant metabolites produced by oxidative dimerization of two phenylpropanoid units. Although their molecular backbone consists only of two phenylpropane (C6-C3) units, lignans show an enormous structural diversity. There is a growing interest in lignans and their synthetic derivatives due to applications in cancer chemotherapy and various other pharmacological effects. This review deals with lignans possessing anticancer, antioxidant, antimicrobial, anti-inflammatory and immunosuppressive activities, and comprises the data reported in more than 100 peer-reviewed articles, so as to highlight the recently reported bioactive lignans that could be a first step towards the development of potential new therapeutic agents.

A novel podophyllotoxin lignan from Justicia heterocarpa

Chromatographic separation of the extract of Justicia heterocarpa T. ANDERS. afforded, in addition to known fatty acids, terpenoids and steroids, a new podophyllotoxin lignan. Structures were elucidated by spectroscopic methods, and the structure of the new lignan was confirmed by single crystal X-ray diffraction studies, which have shown that there is a H-bonding stabilized dimer.

Central nervous activity of elenoside

Elenoside is a cytotoxic arylnapthalene lignan (NSC 644013-W/1) derived from Justicia hyssopifolia (Family: Acanthaceae). The neuropharmacological activity of this lignan, a beta-D-glucoside was studied. The LD50 (24 h) of elenoside in mice is 305 +/- 7 mg/kg by i.p. route. In the present study elenoside was given to rats at doses of 25 and 50 mg/kg, and its effects on locomotor activity (Varimex test), muscular relaxant activity, open-field test and with chlorpromazine, 10 mg/kg was compared. On Varimex test, spontaneous activity was reduced. Elenoside produced a reduction in the permanence time on muscular relaxant activity (traction test). On open-field test, ambulation and rearing were reduced compared with the control group and an increase in boluses of dose-dependent rate was obtained. Thus it can be concluded that elenoside has central sedative effects and possible application in anxiety conditions.

Elenoside, a new cytotoxic drug, with cardiac and extracardiac activity

This paper deals with the effects of elenoside, (3-hidroxymethyl-1-methoxy-5,6-methylene-dioxy-4-(3,4-methylenedioxyphenyl)-2-naftoic acid lactone-beta-D-glucoside) an arylnaphthalene lignan with broad spectrum cytotoxicity in a human tumor cell line panel, isolated from Justicia hyssopifolia (Acanthaceae) grown in the Canary Islands (Spain), on isolated cardiac auricle of rabbits, urinary excretion of rats, and on isolated rat ileum. These effects, using a vehicle (propylene glycol-ethanol-plant oil-Tween 80 (40:10:50:2) as a standard, are presented. Elenoside at concentrations of 3.2x10(-4), 6.4 x 10(-4), and 1.2 x 10(-3) M produced an increase in the contraction force of auricles in a concentration-dependent way. At doses of 25 and 50 mg/kg, an antidiuretic effect and a decrease in sodium excretion were observed. Elenoside at concentrations of 3.2 x 10(-4), 6.4 x 10(-4) and 1.2 x 10(-3) M produced an increase in the contraction force of ileum in a concentration-dependent manner. Elenoside produced the concentration dependent inhibition of 86Rb uptake. These results indicate that elenoside has digitalis-like activity similar to mammalian lignans. Moreover, this lignan has an irritant effect on the gastrointestinal tract.