Pharmacological effects and mechanisms of muscone

Musk, the dried secretion from the preputial follicles of the male musk deer (genus Moschus), possesses various pharmacological activities and has been used extensively in traditional Chinese medicine for thousands of years. Muscone is the main active ingredient of musk and exerts pharmacological effects similar to those of musk. Although muscone was notably used to treat various disorders and diseases, such as neurological disorders, chronic inflammation and ischemia-reperfusion injury, most of the mechanisms of the pharmacological action of muscone remain unclear because of slow progress in research before the 21st century. In recent years, the pharmacological activities and mechanisms of muscone have been clarified. The present article summarizes the pharmacological and biological studies on cerebrovascular disease, cardiovascular disease, neurological effects, cancer and others and the associated mechanisms of the action of muscone to date.

Protective effects of muscone on ischemia-reperfusion injury in cardiac myocytes

ETHNOPHARMACOLOGICAL RELEVANCE

Musk has been traditionally used in Chinese medicine as the main ingredient of many formulations for the treatment of chest pain and angina pectoris.

AIM OF THE STUDY

To investigate the protective effects of muscone (the active ingredient of musk) on ischemia-reperfusion (I/R) injury induced by hypoxia and low glucose in primary cultured rat cardiac myocytes.

MATERIALS AND METHODS

Primary cultures of neonatal rat cardiac myocytes were subjected to ischemia-reperfusion in media, with or without muscone. Cell viability, release of lactic acid dehydrogenase (LDH), superoxide dismutase (SOD) activity, malondialdehyde (MDA) levels, creatine kinase (CK) and caspase-3 activities, as well as intracellular free Ca(2+) concentrations, were measured. Cellular apoptosis and mitochondrial membrane potential (MMP) were assessed by flow cytometry, and the expression of Bcl-2 and Bax proteins was assessed by Western blotting.

RESULTS

Following the exposure of cardiac myocytes to ischemia-reperfusion, there was a marked decrease in pulsating frequency, cell viability, SOD activity, MMP, and the expression of Bcl-2 protein, accompanied by increased LDH release, MDA production, CK and caspase-3 activities, intracellular free Ca(2+) concentrations, rate of apoptosis, and expression of Bax protein. Pretreatment with muscone (0.215, 0.43, 0.86 μg/mL) prior to I/R injury significantly attenuated the above changes.

CONCLUSION

Muscone has a protective effect against I/R injury in cardiac myocytes, indicating that muscone may potentially provide therapeutic benefit in I/R injury by inhibiting cellular oxidative stress and apoptosis.

Toward the development of chemoprevention agents. Part 1: Design, synthesis, and anti-inflammatory activities of a new class of 2,5-disubstituted-dioxacycloalkanes

A new class of 2,5-disubstituted-dioxacycloalkanes were designed and synthesized via stereoselective synthetic method as cancer chemoprevention agents. The anti-inflammatory activities of these compounds were tested using the xylene-induced mouse ear edema model. Some of these compounds exhibited comparable or better anti-inflammatory activities than that of aspirin suggesting that they can be further developed as potential anti-inflammatory drug lead compounds. In addition, treatment of these anti-inflammatory agents did not prolong tail bleeding time in mice. The structure/activity relationships were also analyzed among these compounds.

Stereoselective synthesis and anti-inflammatory activities of 6- and 7-membered dioxacycloalkanes

A class of 5-trifluoroacetylamino-1,3-dioxacycloalkanes, 5-benzoylamino-1,3-dioxacycloalkanes, and 5-amino-1,3-dioxacycloalkane compounds were stereoselectively synthesized as potential anti-inflammatory drug candidates. The anti-inflammatory activities of these compounds were tested using the xylene-induced mouse ear edema model, from which multiple compounds possessing anti-inflammatory properties which surpass aspirin were identified; these compounds were then compared to establish structure-activity relationships.

Capsaicin-induced hyperalgesia and mu-opioid-induced antihyperalgesia in male and female Fischer 344 rats

The influence of sex in determining responses to opioid analgesics has been well established in rodents and monkeys in assays of short-lasting, phasic pain. The purpose of this investigation was to use a capsaicin model of tonic pain to evaluate sex differences in hyperalgesia and mu-opioid-induced antihyperalgesia in Fischer 344 (F344) rats. Capsaicin injected into the tail produced a dose-dependent thermal hyperalgesia in males and females, with the dose required to produce a comparable level of hyperalgesia being 3.0-fold higher in males than in females. These sex differences were modulated by gonadal hormones, inasmuch as gonadectomy increased the potency of capsaicin in males and decreased its potency in females. Morphine, buprenorphine, and dezocine administered by various routes [systemic (s.c.), local (in the tail), and central (i.c.v.)] generally produced marked antihyperalgesic effects in males and females. Although in most instances these opioids were equally potent and effective in males and females, selected doses of local and i.c.v. administered buprenorphine produced greater effects in females. When administered locally, the antihyperalgesic effects of morphine were mediated by peripheral opioid receptors in both males and females, since this effect was not reversed by i.c.v. naloxone methiodide. These data contrast with the finding that mu-opioids are more potent in male rodents in assays of phasic pain, thus suggesting that distinct mechanisms underlie male and female sensitivity to opioid antinociception in phasic and tonic pain models. These findings emphasize the need to test male and female rodents in tonic pain assays that may have greater relevance for human pain conditions.

Use of analgesics during propofol sedation: a comparison of ketorolac, dezocine, and fentanyl

STUDY OBJECTIVE

To evaluate the comparative efficacy and side effect profile of ketorolac 60 mg, dezocine 6 mg, and fentanyl 100 micrograms when used as analgesic supplements to a propofol infusion during monitored anesthesia care (MAC).

DESIGN

Randomized, double-blind, placebo-controlled study.

SETTING

Ambulatory surgery facility at a university medical center.

PATIENTS

80 outpatients undergoing breast biopsy or inguinal herniorraphy procedures under MAC.

INTERVENTIONS

All patients received midazolam 2 mg intravenously (IV) followed by 1 ml of the study medication containing either dezocine 3 mg IV, ketorolac 30 mg IV, fentanyl 50 micrograms IV, or normal saline. A propofol infusion was initiated at 75 micrograms/kg/min and then varied to maintain a stable level of sedation (i.e., Observer Assessment of Alertness/Sedation scale score of 3). An additional 1 ml of the same study medication was administered IV 2 to 3 minutes prior to infiltration of the local anesthetic solution. During the operation, supplemental (rescue) medication consisted of fentanyl 25 micrograms IV, bolus injections in all four treatment groups.

MEASUREMENTS AND MAIN RESULTS

Propofol infusion and supplemental fentanyl dosage requirements, oxygen saturation values, respiratory rates, recovery times, and postoperative side effects were recorded. Visual analog scales were used to assess sedation, anxiety, pain, and nausea preoperatively (baseline), upon entry into the postanesthesia care unit, and at 30-minute intervals until discharge. The fentanyl and dezocine groups required lower average infusion rates of propofol to maintain a stable level of sedation than the control (saline) group. The saline and ketorolac groups required rescue analgesic medication more frequently and/or larger supplemental dosages of fentanyl than the two opioid analgesic treatment groups. Compared with the three analgesic treatment groups, postoperative pain scores were only marginally higher in the control group. Ketorolac-treated patients had consistently (but not significantly) shorter recovery times to oral intake, ambulation, and discharge than those in the dezocine or fentanyl groups. No postoperative nausea, vomiting, or pruritus was reported in the ketorolac group.

CONCLUSION

Compared with ketorolac 60 mg, fentanyl 100 micrograms and dezocine 6 mg produced a greater decrease in the propofol sedation requirement during MAC. However, the use of ketorolac in combination with propofol for MAC was associated with an improved recovery profile.

Serial intravenous doses of dezocine, morphine, and nalbuphine in the management of postoperative pain for outpatients

Adult patients who had arthroscopic surgery under general anesthesia and requested postoperative pain relief were randomized to receive treatment in a double-blind protocol with 5 mg of intravenous dezocine (20 patients), morphine (22 patients), nalbuphine (18 patients), or saline (24 patients). At 10-min intervals, starting with the first dose of analgesic, patients could choose up to three additional doses of the primary treatment, or choose an alternative analgesic if the primary drug was unsatisfactory. One to four doses of morphine were given as the alternate treatment if the initial treatment was dezocine or nalbuphine, and one to four doses of dezocine were given if the initial treatment was saline or morphine. The proportion of patients treated successfully by the initial treatments (i.e., not requesting alternate treatment), with P value for difference from placebo treatment, were saline 25%, nalbuphine 33% (P = 0.048), morphine 54% (P = 0.04), and dezocine 75% (P = 0.003). Dezocine and morphine are more efficacious than nalbuphine in the management of early postoperative pain. As an alternate analgesic in this study, dezocine required fewer doses to achieve patient satisfaction and was thus more efficacious than morphine. The incidence of treatment-related, adverse effects was different from that of saline or other treatments only for nalbuphine-related pain or burning on injection and dezocine-related facial itching. With respect to analgesic actions and side effects, dezocine seems more like morphine than nalbuphine.

Dezocine. A preliminary review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy

Dezocine is an analgesic agent with opioid agonist and antagonist activity. After parenteral administration of therapeutic doses it is approximately equipotent with morphine, and has proved at least as effective an analgesic as morphine, pethidine (meperidine) and butorphanol in moderate to severe postoperative pain. However, preliminary pharmacodynamic data indicate that the ceiling of analgesic activity of dezocine occurs at a higher level of analgesia than that of reference agonist/antagonist agents. Also, the drug exhibited a morphine-like degree of anaesthetic-sparing activity in animals. Although long term data are very limited, single doses of dezocine are well tolerated, with mild and transient sedation and gastrointestinal upset the principal adverse effects. As with some other agonist/antagonist analgesics, a 'ceiling' effect to dezocine-induced respiratory depression occurs with increasing dosage, beyond which further depression has not been observed. In single analgesic doses, however, dezocine is a slightly more potent respiratory depressant than morphine. Clinically important haemodynamic changes have not been observed with usual analgesic doses of dezocine. As an agonist/antagonist opioid, the dependence liability of dezocine would be expected to be lower than that of pure agonist opioids, but extended clinical use is required before more definitive conclusions can be drawn in this regard. Unlike older drugs of its type, dezocine produced opiate-like subjective effects and was identified as morphine-like by drug abusers. Thus, provided the promising conclusions of currently available clinical studies are confirmed with its wider use, dezocine should be a useful additional agent for the treatment of moderate to severe postoperative pain.

Comparison of intramuscular dezocine with butorphanol and placebo in chronic cancer pain: a method to evaluate analgesia after both single and repeated doses

Sixty hospitalized subjects with chronic moderate to severe pain as a result of advanced cancer were enrolled in a randomized, parallel, double-blind trial comparing single doses and multiple doses of intramuscular dezocine (10 mg) with butorphanol (2 mg) and placebo. During the initial 6-hour efficacy evaluation, analgesia was measured using verbal and visual scriptors and vital signs, and acute toxicity information was recorded. Subjects with initial pain relief entered the 7-day multidose portion of the trial, and efficacy and toxicity data were recorded daily. After the initial dose the peak analgesia of the active agents was similar, but the duration of analgesia was longer with dezocine. After multiple doses, dezocine was superior to butorphanol in terms of length of treatment. Dezocine had less toxicity than had butorphanol after both single and repeated doses, further suggesting that dezocine may be beneficial in managing chronic cancer pain. The described study design is unique in that it compares the analgesic efficacy and toxicity of several analgesics with placebo after both single and multiple doses in the same subject. This method may prove to be an alternative pain model to evaluate chronic cancer pain.

Postoperative pain relief: a double-blind comparison of dezocine, butorphanol, and placebo

The safety and efficacy of single intramuscular doses of dezocine (10 or 15 mg) were compared with butorphanol (2 mg) and placebo in 157 patients with moderate to severe postoperative pain. A verbal pain intensity scale, an analog pain intensity scale, and a verbal pain relief scale were used to record the patients' subjective assessments. The results of this study indicate that a single 10 or 15 mg intramuscular injection of dezocine is safe and more effective than placebo for four to six hours, respectively, in the treatment of moderate to severe postoperative pain (P less than .05). During the first hour of treatment the pain relief afforded by 2 mg of butorphanol was significantly greater than that afforded by 10 mg of dezocine (P less than .05), but both doses of dezocine provided long-lasting relief. The scores on all three efficacy scales were highest with the 15 mg dose of dezocine after the first hour, while the 10 mg dose of dezocine and butorphanol were compared during this period. Nausea and vomiting were the most commonly reported side effects; injection site reactions were reported more frequently in the butorphanol group.

Intravenous dezocine for postoperative pain: a double-blind, placebo-controlled comparison with morphine

Dezocine, a new mixed agonist-antagonist opioid analgesic, and morphine were compared in a double-blind study in 206 patients with postoperative pain. The analgesic efficacy of single intravenous injections of dezocine (2.5, 5.0, and 10.0 mg), morphine (5.0 mg), and placebo was assessed by verbal and visual scales at regular intervals for six hours after administration. All active treatments provided greater pain relief than placebo. Pain relief with dezocine 5 and 10 mg was significantly greater (P less than .05) than with placebo for up to four and five hours, respectively, and with morphine up to one hour. Pain relief scores were significantly higher (P less than .05) with morphine than with placebo at all observations except that of the fifth hour, and higher with dezocine 2.5 mg than with placebo for the first 30 minutes. Doses of 5 and 10 mg of dezocine produced approximately the same peak analgesic effect, with the larger dose having a longer duration of effect. All active treatments produced mild to moderate sedation. Side effects were few and mild or moderate with all of the treatments. The physician's and the patients' evaluations favored dezocine in a dose-dependent order, with morphine 5 mg rated lower than dezocine 5 mg and higher than dezocine 2.5 mg.

Double-blind comparison of intravenous doses of dezocine, butorphanol, and placebo for relief of postoperative pain

The safety and efficacy of intravenous doses of dezocine (5 or 10 mg), butorphanol (1 mg), and placebo were compared in a double-blind study in 160 patients with moderate to severe postoperative pain. Analgesic efficacy was assessed for 6 hours after each dose. Mean pain relief scores were consistently higher, indicating greater pain relief, for the three active treatment groups than for the placebo group. The 10-mg dezocine dose was the most effective treatment, and 5 mg of dezocine was comparable to 1 mg of butorphanol. In the 2 hours after the first dose, 32% of the 10-mg dezocine group, 53% of the 5-mg dezocine group, 65% of the butorphanol group, and 88% of the placebo group withdrew from the study because of unsatisfactory pain relief. The differences in these percentages were statistically significant (P less than 0.05) between each active therapy group and the placebo group, and between the 10-mg dezocine group and the butorphanol group. Changes in degree of sedation were similar in the three active therapy groups. Adverse reactions were rare, mild, and equally distributed among the four treatment groups. We conclude that 10 mg of dezocine is superior to 1 mg of butorphanol, and that 5 mg of dezocine is as effective as 1 mg of butorphanol for the relief of moderate to severe postoperative pain.

Double-blind placebo-controlled comparison of dezocine and morphine for post-operative pain relief

Dezocine, a new mixed agonist-antagonist-type opioid analgesic, was compared in a double-blind trial with placebo and 10 mg of morphine in 190 patients with acute postoperative pain. The medications were given intramuscularly. Dezocine was administered at three dose levels (5, 10, and 15 mg). Pain relief scores, sedation, and side effects were recorded at 15, 30, 60, 120 and 240 min after injection. Significantly higher pain relief scores (p less than 0.05) were reported for the groups receiving dezocine 10 and 15 mg than the placebo group at all observation times, except for dezocine 15 mg at four hours. Morphine produced significantly better pain relief than placebo only between the second and fourth hour after administration. Significantly better pain relief was obtained with dezocine (10 and 15 mg) than with morphine during the first hour. The mean four-hour cumulative pain relief scores (TOTPAR) were significantly (p less than 0.05) higher than placebo for all active treatment groups. Side effects were few with no significant differences between the treatment groups. Seventy-nine per cent of the patients in the dezocine 15 mg group, and 73, 68, 58 and 50 per cent respectively, of the patients in the dezocine 10 mg, dezocine 5 mg, morphine 10 mg and placebo group had a satisfactory clinical response. Significantly (p less than 0.05) more patients in the groups receiving dezocine 10 and 15 mg than in the placebo group had a satisfactory clinical response; the difference was not significant for the dezocine 5 mg and morphine 10 mg groups.(ABSTRACT TRUNCATED AT 250 WORDS)

A double-blind comparison of dezocine and morphine in patients with acute renal and ureteral colic

The safety and analgesic efficacy of dezocine and morphine in the treatment of acute renal or ureteral colic due to calculi were evaluated in 2 multicenter, double-blind studies, comparing 10 mg. dezocine and 10 mg. morphine in 88 patients, and 15 mg. dezocine and 10 mg. morphine in 61 patients. All patients received an intramuscular injection of the test drug, and pain intensity and pain relief were evaluated through 4 hours after drug administration. Vital signs, degree of sedation and adverse effects also were recorded. Mean efficacy scores were virtually identical for 10 mg. dezocine and 10 mg. morphine but 15 mg. dezocine produced consistently better analgesia than 10 mg. morphine. This superiority of 15 mg. dezocine was statistically significant on the pain analogue scale at 1 to 4 hours. More morphine-treated than dezocine-treated patients withdrew from each study because of inadequate pain relief. The frequency of adverse effects was not significantly different between groups in either study and none of the patients had clinically significant changes in vital signs. These results indicate that dezocine is a safe and effective analgesic for the treatment of renal and ureteral colic due to calculi, and 15 mg. dezocine were more effective than 10 mg. morphine in this pain model.

Reassessment of verbal and visual analog ratings in analgesic studies

The relative performance of three analgesic rating scales--visual pain analog, verbal pain intensity, and verbal pain relief--was assessed in clinical trials with 1,497 patients and a variety of pain models. The scales correlated strongly with one another, with inconsistent and generally minimal differences in sensitivity. Overall, the verbal relief scale tended to be slightly more sensitive than the pain analog rating, which in turn showed a small advantage over the verbal pain intensity assessment. When the scores derived from the categorized ratings 1 hour after drug dosing (generally the time of peak effect) were analyzed, there was little difference whether a parametric or nonparametric approach was taken. When the cumulative measures of overall effect over 6 hours were considered, however, the nonparametric approach was decidedly more powerful. There was a similar pattern when the analog scores were analyzed. This unanticipated finding appears to be due to the cumulative measures (from all three scales) being more skewed toward the lower end of their respective ranges than are the 1-hour scores. A composite efficacy variable was defined, incorporating data from the three primary scales; this measure was found to be generally comparable in sensitivity to the individual scales and may be useful as a global summary of response. While our investigation provides evidence that any of the ratings considered will accurately reflect analgesic response, the verbal relief scale was the most sensitive and might be the best choice if a single measure is desired.

Dezocine for postoperative wound pain

We assessed the analgesic effectiveness of a single intramuscular injection of dezocine, 10 mg or 15 mg; morphine, 10 mg; or a placebo in 160 patients with moderate to severe postoperative pain. Dezocine, 10 mg, was as effective as and had approximately the same duration of action as morphine, 10 mg. Dezocine, 15 mg, was more effective than 10 mg of either dezocine or morphine as assessed by three efficacy scales (verbal and analog pain intensity and pain relief), and both drugs were significantly (p less than 0.05) more effective than placebo as assessed by the three efficacy scales and the overall evaluation of the investigator. A small percentage of patients suffered nausea and became sedated; the drugs and placebo, however, did not differ statistically with respect to the side effects. Blood pressure, heart rate, and respiratory rate generally were slightly decreased by both drugs.

WY 16225 (dezocine), a new synthetic opiate agonist-antagonist and potent analgesic: comparison with morphine for relief of pain after lower abdominal surgery

Dezocine (Wy 16225), a new analgesic was compared randomly and double-blind with morphine 10 mg in 160 female patients complaining of moderate (group I) or severe (group II) pain after elective lower abdominal surgery; both drugs were given i.m. In group I, pain relief with dezocine 10 and 15 mg was significantly greater than dezocine 5 mg; dezocine 10 mg appeared equipotent with morphine 10 mg. Similar, but statistically insignificant differences were observed in group II. Patient sedation was minimal and untoward side-effects infrequent with all doses of the trial drugs.

Effect of parenteral dezocine and placebo in cancer pain

A double-blind, placebo-controlled crossover trial was carried out in 20 hospitalized patients with continuous pain due to cancer to assess the analgesic effectiveness and tolerance of a single intramuscular injection of 10 mg dezocine. Subjective assessments of pain, made at hourly intervals over 4 hours, showed that dezocine produces a statistically significant greater and sustained relief of pain than did placebo. Only minor side-effects were reported.

Preliminary clinical experience with dezocine, a new potent analgesic

The analgesic effect of a single intravenous dose of dezocine at various dosage levels was studied in 41 patients suffering from acute renal colic. Twenty milligrams was found to be a very effective dose. Out of 25 injections an excellent response was recorded on 21 occasions, with a mean duration of effect of 3.5 hours. In a further 3 patients, pain relief was considered as fair and of shorter duration. Pronounced dizziness was a nearly constant side-effect of the drug. There was no overall effect on blood pressure or heart rate.

A double-blind study of dezocine in cancer pain

A double-blind crossover comparison of intramuscularly administration of 10 mg dezocine (Wy 16225), 10 mg morphine, and placebo in ten patients with cancer pain has shown that a dezocine single dose is superior to placebo in producing relief of moderate to severe pain. No side effects were observed.

In vitro antiviral activity and preliminary clinical trials of a new adamantane compound

A compound, 1'-methyl spiro (adamantane-2,3'-pyrrolidine) maleate, chemically related to the antiviral drug amantadine, was tested for activity in vitro against a number of human respiratory viruses. By a variety of techniques, it was shown to be active against a wide range of human and animal influenza A viruses. The effect was, however, variable and ranged from high activity against two 1957 Asian strains to no observable activity against a 1971 strain. Like amantadine, the drug did not inhibit the growth of influenza B viruses. It was also inactive against a number of paramyxoviruses. Unlike amantadine, the drug did inhibit rhinoviruses, but to a lesser extent than myxoviruses. The coronavirus 229E was also sensitive to the action of the drug in vitro. Although an earlier trial in volunteers showed that, when given orally from 2 days before until 5 days after virus challenge, the drug was protective against infection with influenza A/Hong Kong/68 virus, a similar trial in volunteers challenged with rhinoviruses 2 and 9 revealed no useful activity against rhinoviruses in man.

Tropism of Mycoplasma gallisepticum for arterial walls

The fatal encephalopathy associated with M. gallisepticum strain S6 in turkey poults was completely curable by treatment with tylosin or pleuromutilin. The lesions of cerebral polyarteritis disappeared after therapy. Polyarthritis developed in some birds after recovery from encephalitis. Immunofluorescent studies revealed that intravenously injected organisms became localized as microcolonies within the walls of cerebral and periarticular arteries, and in the glomeruli. Turkey IgG deposition was demonstrated on the glomerular basement membranes, but not in the arterial lesions. The results suggest that the pathologic changes caused by this microorganism are due to selective localization and growth in arteries.

Rimantadine therapy of influenza A infection in mice

Eighty per cent of mice infected with a mouse-adapted strain of influenza virus died within 3 to 8 days after infection. Rimantadine given at maximum protective doses reduced mortality to 10%. This protection is dose related and can be demonstrated with doses from 4.5 to 24 mg per kg per day. Significant survival rates are shown by delaying treatment as long as 48 hr after infection. Lungs of treated mice have significantly less virus than those of controls at 24, 48, and 72 hr after infection. Antibody production as measured by hemagglutination inhibition is not different in treated and controlled mice. These results indicate that rimantadine is an effective prophylactic and therapeutic agent and that its activity is associated with decreased viral titers.