Synthesis and antitussive evaluation of verticinone-cholic acid salt, a novel and potential cough therapeutic agent

Pharmacokinetics, tissue distribution and excretion of verticinone from F. hupehensis in rats

Verticinone, the main active component in F. hupehensis, exhibits potent antitussive and expectorant effects. Here, a LC-MS method was developed and applied to study the pharmacokinetics, tissue distribution and excretion of verticinone in rats, and its plasma protein binding in vitro. A significant gender difference in the pharmacokinetics of verticinone in rats was observed, as its absolute oral bioavailability in male and female rats was 45.8% and 2.74%, respectively. The relative bioavailability of verticinone was significantly lower in female rats as compared to male, following intragastrical (i.g.) and intravenous (i.v.) administration. After successive i.g. administration of verticinone, accumulation was observed in female rats but not in the male ones. The tissue distribution study showed that verticinone had a good tissue penetrability and a high tissue affinity in most studied tissues, except brain. After a 2 mg/kg oral dose, less than 4% of the dose was excreted as unchanged parent compound in male rats, and less than 1% in female rats, which indicated that verticinone was metabolized more extensively in female rats than in male rats.

Antinociceptive efficacy of verticinone in murine models of inflammatory pain and paclitaxel induced neuropathic pain

Verticinone, an isosteroidal alkaloid separated from Bulbus Fritillaria (Chinese name "Bei-mu"), was evaluated for its analgesic activities in murine models of inflammatory and neuropathic pain. It was shown that oral administarion of verticinone could significantly inhibit acetic acid-induced writhing response in a dose-dependent way, and the writhing inhibition of 3 mg/kg verticinone was 66.2%, which was approximately higher than that of 200 mg/kg aspirin. In the formalin test, a high dose of (3 mg/kg) verticinone could inhibit the nociceptive response of both phases, but the lower dose (1.5 mg/kg) could only inhibit the second phase response, which suggested that verticinone might exert its analgesic effect through both central and peripheral mechanisms. In addition, in formalin and acetic acid tests, the spontaneous locomotive activities of the mice treated with verticinone were transiently greatly decreased when compared with the vehicle group. In the rat model of paclitaxel induced neuropathic pain, in contrast to the declined analgesic effect of morphine after repeated administration with the same dose, a relatively constant analgesic effect of verticinone was observed. These investigations suggested that verticinone could exert a good antinociceptive effect on inflammatory pain and cancer-related neuropathic pain probably through both peripheral and central mechanisms, and it might be partly involved with some sedation effects. Verticinone is expected to become a potentially novel sedative-analgesic agent without producing tolerance and dependence, but further studies are still urgently needed to elucidate the precise mechanisms and activities of it.

Endogenous opiates and behavior: 2007

This paper is the thirtieth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2007 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.