Biological activities of lignans

A review of medicinal plants showing anticonvulsant activity

This paper provides an overview of the pharmacological features of honokiol (3′,5-di-2-propenyl-1,1′-biphenyl-2,4′-diol), an isomer of neolignans isolated and identified from the stem bark of Magnoliaceous plants (Magnolia obovata Thunb, Wa-Koboku in Japanese). The magnolia bark has been utilized as a herbal remedy for the treatment of a wide variety of clinical disorders. Honokiol and magnolol (an isomer of honokiol) were recently identified as anxiolytic agents in the extracts of Saiboku-to, an oriental herbal medicine (Kampo). Behavioral evaluation through an elevated plus-maze test demonstrated that honokiol, 0.2–2 mg/kg, p.o., for 7 days, was at least 5000 times more potent than Saiboku-to. Honokiol has a comparatively lower risk of causing benzodiazepine-like side effects, such as central depression, muscle relaxation, amnesia, or physical dependence. In addition to these central actions, a wide variety of pharmacological effects and biochemical activities of honokiol have been reported during the past 10 years. The main effects, including the limited information regarding the metabolism and kinetics of the compound, are briefly introduced in this text. Information available on honokiol, including its specific and simple chemical structure, suggests the possibility of deriving more potent compounds in the drug design process.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1527-3458.2000.tb00136.x

Overview of the Pharmacological Features of Honokiol

A review of the phytochemistry and pharmacological activities of Magnoliae officinalis cortex.

Kampo medicines have been used to treat patients with psychogenic disorders from ancient times. In the present report the cases are described of four patients with panic disorder successfully treated with Kampo medicines. These four patients fulfilled the Diagnostic and Statistical Manual of Mental Disorders (DSM) criteria for panic disorder with agoraphobia. The Kampo medicine Kami-shoyo-san (TJ-24) relieved panic attacks, anticipatory anxiety and agoraphobia in two patients, and Hange-koboku-to (TJ-16) relieved these symptoms in the other two patients. The patients in whom Kami-shoyo-san was effective were older and complained of more symptoms than those in whom Hange-koboku-to was effective. These Kampo medicines may be useful as additional or alternative treatments for panic disorder.

Four cases of panic disorder successfully treated with Kampo (Japanese herbal) medicines: Kami-shoyo-san and Hange-koboku-to.

Pharmacological properties of the extracts from the magnolia cortex (the bark of Magnolia obovata THUNB.) were examined with special reference to their central nervous system action. The ether extract of the magnolia (1g/kg i.p.) markedly depressed the spontaneous activity of mice and chicks, while the water extract (1g/kg i.p.) procuced prompt paralysis of respiration. Distinct muscle weakness was found after administraction of the ether extract, through the clinging power test on the wire net, and was different from the effect of the water extract. The ether extract supressed convulsion produced by strychnine, picrotoxin, or pentetrazol. Tremor by oxotremorine was also blocked by the ether extract. Pentetrazol infusion technique was employed for the elucidation of the mode of this drug action. Depressive effect of the ether extract was also exerted on the crossed extensor reflex of the chick spinal cord.

Kyosuke Yoshitomi

Papers

Central Depressant Effects of the Extracts of Magnolia Cortex