Magnolia Extract, Magnolol, and Metabolites: Activation of Cannabinoid CB2 Receptors and Blockade of the Related GPR55.

The bark of Magnolia officinalis is used in Asian traditional medicine for the treatment of anxiety, sleeping disorders, and allergic diseases. We found that the extract and its main bioactive constituents, magnolol and honokiol, can activate cannabinoid (CB) receptors. In cAMP accumulation studies, magnolol behaved as a partial agonist (EC50 = 3.28 µM) with selectivity for the CB2 subtype, while honokiol was less potent showing full agonistic activity at CB1 and antagonistic properties at CB2. We subsequently synthesized the major metabolites of magnolol and found that tetrahydromagnolol (7) was 19-fold more potent than magnolol (EC50 CB2 = 0.170 µM) exhibiting high selectivity versus CB1. Additionally, 7 behaved as an antagonist at GPR55, a CB-related orphan receptor (K B = 13.3 µM, ß-arrestin translocation assay). Magnolol and its metabolites may contribute to the biological activities of Magnolia extract via the observed mechanisms of action. Furthermore, the biphenylic compound magnolol provides a simple novel lead structure for the development of agonists for CB receptors and antagonists for the related GPR55.

Interactions of Magnolia and Ziziphus extracts with selected central nervous system receptors.

ETHNOPHARMACOLOGICAL RELEVANCE: Magnolia officinalis Rehder and Wilson [Magnoliaceae] bark and Ziziphus spinosa (Buhge) Hu ex. Chen. [Fam. Rhamnaceae] seed have a history of use in traditional Asian medicine for mild anxiety, nervousness and sleep-related problems. AIM OF THE STUDY: To identify pharmacological targets, extracts of Magnolia officinalis (ME), Ziziphus spinosa (ZE), and a proprietary fixed combination (MZE) were tested for affinity with central nervous system receptors associated with relaxation and sleep. METHODS: In vitro radioligand binding and cellular functional assays were conducted on: adenosine A(1), dopamine (transporter, D(1), D(2S), D(3), D(4.4) and D(5)), serotonin (transporter, 5-HT(1A), 5-HT(1B), 5-HT(4e), 5-HT(6) and 5-HT(7)) and the GABA benzodiazepine receptor. RESULTS: Interactions were demonstrated with the adenosine A(1) receptor, dopamine transporter and dopamine D(5) receptor (antagonist activity), serotonin receptors (5-HT(1B) and 5-HT(6) antagonist activity) and the GABA benzodiazepine receptor at a concentration of 100 microg/ml or lower. ME had an affinity with adenosine A(1) (K(i) of 9.2+/-1.1 microg/ml) and potentiated the GABA activated chloride current at the benzodiazepine subunits of the GABA receptor (maximum effect at 50 microg/ml). ME had a modest antagonist action with 5-HT(6) and ZE with the 5-HT(1B) receptor. CONCLUSION: The interactions in the receptor binding models are consistent with the traditional anxiolytic and sleep-inducing activities of Magnolia officinalis bark and Ziziphus spinosa seed.

Hypothermic effects of hops are antagonized with the competitive melatonin receptor antagonist luzindole in mice.

Hops (Humulus lupulus, Cannabinaceae) has been used in traditional European medicine as a mild sedative for the treatment of anxiety, nervousness, and insomnia. However, there has been little information available about the underlying sleep inducing mechanism of hops. We have investigated the effects of a hops extract on the rectal body temperature in mice. Hops extract (250 mg kg(-1)) significantly decreased body temperature in male BL6/C57J mice (DeltaT -0.75 +/- 0.07 degrees C) 2 h after oral administration. The effects of the plant extract were comparable with melatonin (50 mg kg(-1); DeltaT -0.66 +/- 0.06 degrees C; 2 h after i.p. injection). The hypothermic effects of melatonin and hops extract were antagonized with the competitive melatonin receptor antagonist luzindole. Thus, our data suggests that the hypothermic--and therefore the sleep-inducing--effects of hops extract are possibly mediated through activation of melatonin receptors.

Efficacy and safety of butterbur herbal extract Ze 339 in seasonal allergic rhinitis: postmarketing surveillance study.

The efficacy and safety of the butterbur leaf extract Ze 339 (carbon dioxide extract from the leaves of Petasites hybridus L., 8 mg petasines per tablet) were tested in patients with seasonal allergic rhinitis. In an open postmarketing surveillance study, 580 patients were treated with an average of 2 tablets of Ze 339 daily for 2 weeks. Symptoms of rhinorrhea, sneezing, nasal congestion, itchy eyes and nose, red eyes, and skin irritation were evaluated on a visual analogue scale. Symptoms of seasonal allergic rhinitis improved in 90% of patients. Differences observed before and after therapy were significant and clinically relevant for all symptoms. Improvement reported by the end of the study was found to be inversely related to symptom severity as described at baseline. Efficacy, tolerability, and improvement in quality of life were positively rated by 80%, 92%, and 80% of patients, respectively. A total of 44% of patients were given an antiallergic comedication. This combination did not result in a better effect than was attained with Ze 339 monotherapy. Adverse events occurred at a rate of 3.8%, and gastrointestinal complaints were predominantly nonspecific. Results of this postmarketing surveillance trial are consistent with observations documented in previous randomized, double-blind, prospective, controlled trials of the same extract that were conducted according to Good Clinical Practice (GCP). Butterbur leaf special extract Ze 339 was confirmed by 3 GCP trials and 2 postmarketing surveillance trials to be safe and efficacious in the treatment of patients with seasonal allergic rhinitis.

Valerian-hops combination and diphenhydramine for treating insomnia: a randomized placebo-controlled clinical trial.

CONTEXT: Insomnia is a prevalent health complaint associated with daytime impairments, reduced quality of life, and increased health-care costs. Although it is often self-treated with herbal and dietary supplements or with over-the-counter sleep aids, there is still little evidence on the efficacy and safety of those products. OBJECTIVE: To evaluate the efficacy and safety of a valerian-hops combination and diphenhydramine for the treatment of mild insomnia. DESIGN AND SETTING: Multicenter, randomized, placebo-controlled, parallel-group study conducted in 9 sleep disorders centers throughout the United States. PATIENTS: A total of 184 adults (110 women, 74 men; mean age of 44.3 years) with mild insomnia. INTERVENTIONS: (1) Two nightly tablets of standardized extracts of a valerian (187-mg native extracts; 5-8:1, methanol 45% m/m) and hops (41.9-mg native extracts; 7-10:1, methanol 45% m/m) combination for 28 days (n = 59), (2) placebo for 28 days (n = 65), or (3) 2 tablets of diphenhydramine (25 mg) for 14 days followed by placebo for 14 days (n = 60). OUTCOME MEASURES: Sleep parameters measured by daily diaries and polysomnography, clinical outcome ratings from patients and physicians, and quality of life measures. RESULTS: Modest improvements of subjective sleep parameters were obtained with both the valerian-hops combination and diphenhydramine, but few group comparisons with placebo reached statistical significance. Valerian produced slightly greater, though nonsignificant, reductions of sleep latency relative to placebo and diphenhydramine at the end of 14 days of treatment and greater reductions than placebo at the end of 28 days of treatment. Diphenhydramine produced significantly greater increases in sleep efficiency and a trend for increased total sleep time relative to placebo during the first 14 days of treatment. There was no significant group difference on any of the sleep continuity variables measured by polysomnography. In addition, there was no alteration of sleep stages 3-4 and rapid eye movement sleep with any of the treatments. Patients in the valerian and diphenhydramine groups rated their insomnia severity lower relative to placebo at the end of 14 days of treatment. Quality of life (Physical component) was significantly more improved in the valerian-hops group relative to the placebo group at the end of 28 days. There were no significant residual effects and no serious adverse events with either valerian or diphenhydramine and no rebound insomnia following their discontinuation. CONCLUSIONS: The findings show a modest hypnotic effect for a valerian-hops combination and diphenhydramine relative to placebo. Sleep improvements with a valerian-hops combination are associated with improved quality of life. Both treatments appear safe and did not produce rebound insomnia upon discontinuation during this study. Overall, these findings indicate that a valerian-hops combination and diphenhydramine might be useful adjuncts in the treatment of mild insomnia.

A stability-indicating HPLC method for the determination of glucosamine in pharmaceutical formulations.

A stability-indicating high performance liquid chromatographic (HPLC) method was developed for the assay of glucosamine in bulk forms and solid dosage formulations. The HPLC separation was achieved on a Phenomenex Luna amino column (150 mm x 4.6 mm, i.d., 5 microm particle size) using a mobile phase of acetonitrile-phosphate buffer (75:25, v/v, pH 7.50) at a flow rate of 1.5 ml min(-1) and UV detection at 195 nm. The method was validated for specificity, linearity, solution stability, accuracy, precision, limit of detection, and limit of quantitation. The detector response for glucosamine hydrochloride was linear over the selected concentration range from 1.88 to 5.62 mg ml(-1) with a correlation coefficient 0.9998. The accuracy was between 98.9 and 100.5%. The precision (R.S.D.) amongst six sample preparations was 1.1%. The limit of detection and the limit of quantitation are 0.037 and 0.149 mg ml(-1), respectively. The sample and standard solutions were stable for 1 week. The method was successfully used for analysis of active-excipient compatibility samples used for development of a solid dosage formulation in our laboratory and subsequent stability studies. The method was also used for the analysis of glucosamine in several commercially available solid dosage forms.

Structural identification of nonvolatile dimerization products of glucosamine by gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, and nuclear magnetic resonance analysis.

The degradation profile of glucosamine bulk form stressed at 100 degrees C for 2 h in an aqueous solution was studied. Column chromatography of acetylated product mixture led to isolation of two pure compounds (1b and 2b) and a mixture of at least three isomers (3b). 1a and 2a were identified as 5-(hydroxymethyl)-2-furaldehyde (5-HMF) and 2-(tetrahydroxybutyl)-5-(3',4'-dihydroxy-1'-trans-butenyl)pyrazine, respectively, by utilizing a variety of analytical techniques, such as GC-MS, LC-MS, on-line UV spectrum, (1)H and (13)C NMR, and DEPT, as well as (1)H-(1)H COSY. 3a was identified as 2-(tetrahydroxybutyl)-5-(2',3',4'-trihydroxybutyl)pyrazine, commonly known as deoxyfructosazine. In addition, glucosamine solid dosage form was exposed to 40 degrees C/75% relative humility for 10 weeks. Methanol extract of glucosamine solid dosage form was analyzed after acetylation by LC-MS, resulting in degradants 3b and 4b. 3a and 4a were, therefore, determined as deoxyfructosazine and 2,5-bis(tetrahydroxybutyl)pyrazine (fructosazine), respectively. Furthermore, the mechanisms of formation of identified degradation products are proposed and briefly discussed.

Interactions of valerian extracts and a fixed valerian-hop extract combination with adenosine receptors.

Phytopharmaceuticals and dietary supplements containing valerian are used as mild sleep-inducing agents. An in vitro radioligand binding assay at A(1) and A(2A) adenosine receptors (ARs) was conducted with a fixed extract combination of valerian and hop (Ze 91019) to investigate a possible mechanism for the pharmacological activity of the extract. Component extracts of valerian and hop were also individually investigated. The fixed combination Ze 91019 as well as the valerian extracts therein exhibited selective affinity to A(1)ARs (K(i) = 0.15-0.37 mg/mL vs [(3)H]CCPA). The same extracts exhibited partial agonist activity at the A(1) adenosine receptor as indicated by a lower degree of stimulation of [35S]GTP gamma S binding in membrane preparations of CHO-hA(1) cells as compared to the full A(1) AR agonist N(6)-cyclopentyladenosine (CPA). In addition valerian extract inhibited cAMP accumulation in CHO-hA(1) cell membranes. The partial agonistic activity at A(1)ARs may thus play a role in the sleep inducing effect of Ze 91019 and the valerian extract therein.