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Poria cocos ethanol extract and its active constituent, pachymic acid, modulate sleep architectures via activation of GABAA-ergic transmission in rats
Abstract
Poria cocos is a well-known traditional Chinese traditional medicine (TCM) that grows around roots of pine trees in China, Korea, Japan, and North America. Poria cocos has been used in Asian countries to treat insomnia as either a single herb or part of an herbal formula. In a previous experiment, pachymic acid (PA), an active constituent of Poria cocos ethanol extract (PCE), increased pentobarbital-induced sleeping behaviors. The aim of this experiment was to evaluate whether or not PCE and PA modulate sleep architectures in rats as well as whether or not their effects are mediated through GABA(A)-ergic transmission. PCE and PA were orally administered to individual rats 7 days after surgical implantation of a transmitter, and sleep architectures were recorded by Telemetric Cortical encephalogram (EEG) upon oral administration of test drugs. PCE and PA increased total sleep time and non-rapid eye movement (NREM) sleep as well as reduced numbers of sleep/wake cycles recorded by EEG. Furthermore, PCE increased intracellular chloride levels, GAD65/67 protein levels, and alpha-, beta-, and gamma-subunits of GABA(A) receptors in primary cultured hypothalamic neuronal cells. These data suggest that PCE modulates sleep architectures via activation of GABA(A)-ergic systems. Further, as PA is an active component of PCE, they may have the same pharmacological effects.
... As presented in Table I, PA at a dose of 5 mg/kg suppresses locomotor activity, prolongs sleep time and enhances hypnotic effects in pentobarbital-treated mice via chloride channel activation and GABA-ergic mechanisms (13). Their subsequent study further indicated that PA increases total sleep time and non-rapid eye movement sleep, and reduces the number of sleep/wake cycles and wakefulness (72). To the best of our knowledge, no lanostane-type triterpenoids have been reported to show sedative-hypnotic effects, except for PA. ...
... It demonstrates significant anti-inflammatory effects by inhibiting the activity of PLA2 (56). To the best of our knowledge, no lanostane-type triterpenoids have been reported to show sedative-hypnotic effects, except PA (72). ...
... Third, regarding the stage of current research on the pharmacology and molecular mechanism of PA, further investigation of the in vivo effectiveness and efficiency of PA should be performed. Fourth, special pharmacological profiles of PA, such as its sedative-hypnotic effect, should be given more attention, as no other lanostane-type triterpenoids have been reported to exhibit a sedative-hypnotic effect (13,72). Fifth, novel PA derivatives library for exploring more promising candidates with higher pharmacological activities and improved drug-like properties should be performed. ...
Poria cocos is a saprophytic fungus that grows in diverse species of Pinus. Its sclerotium, called fu-ling or hoelen, has been used in various traditional Chinese medicines and health foods for thousands of years, and in several modern proprietary traditional Chinese medicinal products. It has extensive clinical indications, including sedative, diuretic, and tonic effects. Pachymic acid (PA) is the main lanostane-type triterpenoid in Poria cocos. Evidence suggests that PA has various biological properties such as cytotoxic, anti-inflammatory, antihyperglycemic, antiviral, antibacterial, sedative-hypnotic, and anti-ischemia/reperfusion activities. Although considerable advancements have been made, some fundamental and intricate issues remain unclear, such as the underlying mechanisms of PA. The present study aimed to summarize the biological properties and therapeutic potential of PA. The biosynthetic, pharmacokinetic, and metabolic pathways of PA, and its underlying mechanisms were also comprehensively summarized.
... In studies to alleviate or modulate the symptoms of these disorders, such as apathy, depression, sleep disruption, and psychosis, which are the core features of patients with AD, Sun et al. identified that the PC extract could ameliorate cognitive function by reducing amyloid-β formation and improving amyloid-β clearance in an AD mouse model [30]. Another study showed that PC regulated the sleep architecture via a GABAA-ergic mechanism, which increased the protein expression of GAD65/67 and GABAA receptor subunits in the primary hypothalamic neuronal cells [31]. Overall, the pharmacological MOA derived from these two analyses can explain the herbal efficacy of PC and the latest research findings. ...
We characterized the therapeutic biological modes of action of several terpenes in Poria cocos F.A Wolf (PC) and proposed a broad therapeutic mode of action for PC. Molecular docking and drug-induced transcriptome analysis were performed to confirm the pharmacological mechanism of PC terpene, and a new analysis method, namely diffusion network analysis, was proposed to verify the mechanism of action against Alzheimer’s disease. We confirmed that the compound that exists only in PC has a unique mechanism through statistical-based docking analysis. Also, docking and transcriptomic analysis results could reflect results in clinical practice when used complementarily. The detailed pharmacological mechanism of PC was confirmed by constructing and analyzing the Alzheimer’s disease diffusion network, and the antioxidant activity based on microglial cells was verified. In this study, we used two bioinformatics approaches to reveal PC’s broad mode of action while also using diffusion networks to identify its detailed pharmacological mechanisms of action. The results of this study provide evidence that future pharmacological mechanism analysis should simultaneously consider complementary docking and transcriptomics and suggest diffusion network analysis, a new method to derive pharmacological mechanisms based on natural complex compounds.
... According to research, benzodiazepines can affect a variety of brain rhythmic processes by inhibiting the release of the inhibitory neurotransmitter GABA. Pachymic acid from the ethanol extract of Poria cocos, which is the main target in this study, alters sleep patterns by stimulating GABA-ergic systems [22]. In this study, they were able to successfully promote health booster supplements using Poria cocos ethanol extract, as well as effectively conduct a clinical trial using it, and report the findings. ...
Background:
Since the outbreak of the pandemic started, an increase in the number of sleep disorders, including insomnia and poor sleep quality, has been seen. The pattern will probably continue.
Methods:
This study focuses on the preparation and clinical testing of Poria cocos extract in treating suboptimal sleep quality. The optimal extraction method utilized a 75% ethanol concentration, and the clinical investigation involved subjects with defined poor sleep taking 800 mg of the extract nightly, assessed using the Sleep Questionnaire and polysomnography. The non-parametric Wilcoxon signed-rank test was used for statistical analysis due to the non-normal distribution of the collected data.
Results:
The study involved 21 insomnia sufferers with a mean age of 55 who were administered Poria cocos extracts. The findings of the study indicate a statistically significant rise in the overall duration of sleep (from 327.395 ± 43.2 min to 356.516 ± 63.21 min, p = 0.014). Additionally, there was a notable decrease in the level of arousal during sleep (from 76.316 ± 44.78 min to 47.989 ± 42.38 min, p = 0.009), and an improvement in the sleep severity index of the sleep questionnaire test.
Conclusions:
Poria cocos as a natural substance could improve quality of sleep, based on the findings. The study investigates Pachymic acid, a substance found in Poria cocos, as a potential indicator for the development of sleeping aids.
... Glutamic acid decarboxylase (GAD 65/67 ) is a rate-limiting enzyme responsible for the conversion of Glu to GABA, and plays a key role in maintaining the GABA level in the CNS (Shah et al. 2015). Thus, changes in the expression levels of this enzyme might influence GABA transmission in the brain. ...
Context
Moringa oleifera Lam. (Moringaceae) (MO) is an important food plant that has high nutritional and medical value. However, there is limited information on whether its seeds can improve sleep.
Objective
This study investigated the effects of MO seed ethanol extracts (EEMOS) on sleep activity improvement and examined the underlying mechanisms.
Materials and methods
Male ICR mice were placed into six groups (n = 12) and treated as follows: Control (sodium carboxymethyl cellulose, 20 mL/kg), estazolam tablets (2 mg/kg), EEMOS (1, 2 g/kg) and kaempferol (1, 2 mg/kg). These samples were successively given intragastric for 14 d. Locomotor activity assay, pentobarbital-induced sleeping and pentetrazol-induced seizures tests were utilized to examine the sedative-hypnotic effects (SHE) of EEMOS.
Results
Compared with the control group, the results revealed that EEMOS (2 g/kg) and KA (2 mg/kg) possessed good SHE and could significantly elevate the levels of γ-aminobutyric acid and reduce the levels of glutamic acid in the mouse hypothalamus (p < 0.05). Moreover, SHE was blocked by picrotoxin, flumazenil and bicuculline (p < 0.05). EEMOS (2 g/kg) and KA (2 mg/kg) significantly upregulated the protein expression levels of glutamic acid decarboxylase-65 (GAD65) and α1-subunit of GABAA receptors in the hypothalamus of mice (p < 0.05), not affecting glutamic acid decarboxylase-67 (GAD67) and γ2-subunit expression levels (p > 0.05). Additionally, they cause a significant increase in Cl⁻ influx in human cerebellar granule cells at a concentration of 8 µg/mL (p < 0.05).
Discussion and conclusions
These findings demonstrated that EEMOS could improve sleep by regulating GABAA-ergic systems, and encourage further clinical trials to treat insomnia.
... Wolfiporia cocos)), a well-known tonic and anti-aging traditional Chinese medicine, has been widely used as a sedative and diuretic for more than two thousand years [20]. P. cocos has been demonstrated to have anti-inflammatory, anti-tumor, anti-hyperglycemic, sedative, and anti-aging functions with lanostane triterpenoids identified as the active components [21][22][23][24][25][26][27][28][29][30]. In addition, the ethyl acetate fraction and crude polysaccharide fraction of P. cocos have been shown to enhance immunity in animal models based on the serum hemolysis content test, phagocytic effect of mononuclear macrophages and the level of lymphocyte transformation. ...
Poria cocos (Schwein) F.A. Wolf (syn. Wolfiporia cocos) dried sclerotium, called fuling, is an edible, saprophytic fungus commonly used as a tonic and anti-aging traditional Chinese medicine. It is traditionally used in combination with other traditional Chinese medicines to enhance immunity. This study showed that P. cocos extract (Lipucan®) containing lanostane triterpenoids has no immunotoxicity and enhances non-specific (innate) immunity though activating natural killer cells and promotes interferon γ (IFN-γ) secretion by Type 1 T-helper (Th1) cells immune response. In addition, P. cocos extract significantly decreased interleukin (IL-4 and IL-5) secretion by Type 2 T-helper (Th2) cells immune response, which are related to the allergy response. The purified lanostane triterpenoids were first identified as active ingredients of P. cocos with enhanced non-specific immunity by promoting interferon γ (IFN-γ) secretion in a preliminary study. Our findings support that the P. cocos extract plays beneficial roles in immunoregulatory activity.
... The intracellular Cl − concentration was measured using a Cl − sensitive fluorescence probe, N-(Ethoxycarbonylmethyl)-6-methoxyquinolinium bromide (MQAE), according to previous reports, with slight modification [38,39]. Briefly, the cells were incubated overnight at 37°C, 5% CO 2 incubator with 10 μM MQAE (Sigma) in the culture medium. ...
The present study was conducted to investigate the sedative and hypnotic activities of Vaccinium bracteatum Thunb. fruit (VBFW) in an animal model and to identify the underlying mechanisms of its action.VBFW exhibited sedative effects through a reduction in the locomotor activity in the open field test (OFT). In addition, VBFW significantly reduced the sleep latency and increased total sleep duration in pentobarbital-induced sleeping behaviors in mice. The effects of 4-Chloro-DL-phenylalanine methyl ester hydrochloride (PCPA) were studied in normal and serotonin-depleted mice. Additionally, the changes in the related serum corticosterone (CORT) and neurotransmitter levels were evaluated. Pretreatment with VBFW (50, and 100 mg/kg) produced a significant decrease in the immobility time in the forced swim test (FST), while VBFW 100 plus PCPA treatment attenuated the change in immobility time observed following administration of VBFW alone. However, VBFW plus PCPA treatments did not significantly influence the changes in the locomotor activity that were induced by VBFW alone. The results suggest that VBFW leads to a decrease in the levels of serum CORT and norepinephrine in the hippocampus (HC) region (P
Unlabelled:
Tyrosinase inhibitors are commonly used in the pharmaceutical and cosmetic industries for skin lightening and hypopigmentation. The current inhibitors of tyrosinase induce strong safety concerns which necessitate the discovery of new inhibitors. Natural compounds are a promising solution to discover potential candidate for anti-melanogenic activity as they possess less safety concerns and high therapeutic effect. The current study aimed to screen and identify potential phytochemicals from Poria cocos for tyrosinase inhibition. The phytochemicals were obtained from the Traditional Chinese Medicine System Pharmacology Database and screened for druglikeness score and toxicity class and then subjected to in-silico virtual screening and molecular dynamics. 7,9-(11)-Dehydropachymic acid established hydrogen interaction with the tyrosinase protein and was found to be highly stable as validated with MD simulations. The pharmacokinetic results showed that this compound has adequate toxicity and ADME profile that can be exploited for anti-melanogenic effects. Our study identified 7,9-(11)-dehydropachymic acid as an efficient candidate for tyrosinase inhibition.
Supplementary information:
The online version contains supplementary material available at 10.1007/s13205-023-03626-8.
Medicinal plants are of great importance since they exert beneficial pharmacological effects. In this study, phytochemical analysis of the ethanolic extract of the leaves of Trema (T.) cannabina Lour (family Cannabaceae) revealed the presence of carbohydrate, alkaloids, steroid, tannin and absence of gum, saponins, glycosides. Herein, a series of investigations were conducted with the extract to confirm the antioxidative, analgesic, antidiarrhoeal, and antimicrobial properties. T. cannabina extract showed antioxidant activity, both qualitatively and quantitatively. It displayed free radical scavenging activity in the 2,2-diphenylpicrylhydrazyl (DPPH) assay (IC50 = ≈201 µg/mL) which is comparable to that of ascorbic acid (IC50 = ≈13 µg/mL), a well-known standard antioxidant. Further, 250 and 500 mg/kg of the extract exhibited 28.95% (p=0.07) and 40.79% (p<0.02) inhibition of writhing reflex, respectively compared to the standard drug diclofenac (25 mg/kg, inhibition of writhing reflex 69.74%) in mice. In addition, we found significantly reduced number of stools with the extract at these doses (p<0.001) compared to the standard drug loperamide (3 mg/kg, p<0.001) in the castor oil-induced diarrhoeal mice. Interestingly, the extract (500µg/disc) suggested credible antibacterial properties against the bacterial strains; Enterococcus faecalis, Streptococcus pyogenes, Shigella dysenteriae, Vibrio cholera and no activity against Escherichia coli, Shigella boydii, Staphylococcus aureus, Staphylococcus epidermidis and Proteus mirabilis. For the comparison of antimicrobial properties, standard antibiotic discs of Kanamycin were used. Collectively, the obtained results provide compelling evidence for the role of T. cannabina in exerting antioxidant, analagesic, antidiarrhoeal, and antimicrobial effects, which rationale the use of this plant in traditional medicine. However, further investigations are required to confirm these effects at molecular level.
Sleep disorders may have various causes and can incur mental and/or physical symptoms, and affect an individual’s quality of life. In this study, we confirm that the Poria cocos extract (PCET) can improve sleep quality and structure by promoting inhibitory neurotransmission via the γ-aminobutyric acid (GABA) type A (GABAA) receptors based on the mechanisms revealed in the experiment with superior cervical ganglion neurons. Pentobarbital-induced sleep tests were conducted in order to determine whether the PCET extract improves the sleep quality and structure in normal ICR mice. Sleep latency and duration were checked with the righting reflex. To simulate the state of awakening as well as a normal sleep state, caffeine was administered orally before the PCET diet. After oral gavage of PCET, sleep latency was decreased, and total sleep duration was increased in normal and caffeine-induced sleep disturbance state. In the ACTH-induced sleep disturbed models, administration of PCET significantly reduced the sleep latency and increased the non-REM sleep duration, which was analyzed in real-time EEG by implanting wireless electrodes in SD rats. PCET was found to improve the sleep quality under a normal sleep state through the GABAA receptor; it also promoted and improved the sleep quality and sleep structure in both the arousal activation state and stress-based sleep disturbance.
Introduction:
The aim of this study is to report the effect of Ling-Gui-Gan-Zao-Tang (LGGZT) effectively improves anxiety disorder following traumatic brain injury (TBI).
Case Presentation:
50-year-old female with traumatic brain injury after falling down from golf cart. After injury, symptoms like anxiety disorder, diarrhea, dizziness, headache were occurred. She took medications like antidepressants, antianxiety drugs and antipsychotic agent, but symptoms deteriorated consistently. After being prescribed LGGZT, patients' symptoms were significantly improved. Result of Impact Event Scale-Revised (IES-R-K) was changed from 24 to 5 and Beck Anxiety Inventory (BAI) was changed from 21 to 3. Also, side effects were not observed during the treatment period.
Conclusion:
LGGZT can be considered as an effective treatment for anxiety disorder following traumatic brain injury.
Key words:
case report, traumatic brain injury, Ling-Gui-Gan-Zao-Tang, Yeonggyegamjo-tang, anxiety disorder
This study was investigated to know whether pachymic acid (PA), one of the predominant triterpenoids in Poria cocos (Hoelen) has the sedative-hypnotic effects, and underlying mechanisms are mediated via γ-aminobutyric acid (GABA)-ergic systems. Oral administration of PA markedly suppressed locomotion activity in mice. This compound also prolonged sleeping time, and reduced sleep latency showing synergic effects with muscimol (0.2 mg/kg) in shortening sleep onset and enhancing sleep time induced by pentobarbital, both at the hypnotic (40 mg/kg) and sub-hypnotic (28 mg/kg) doses. Additionally, PA elevated intracellular chloride levels in hypothalamic primary cultured neuronal cells of rats. Moreover, Western blotting quantitative results showed that PA in-creased the amount of protein level expression of GAD65/67 over a broader range of doses. PA increased α- and β-subunits protein levels, but decreased γ-subunit protein levels in GABAA receptors. The present experiment provides evidence for the hypnotic effects as PA enhanced pentobarbital-induced sleeping behaviors via GABAA-ergic mechanisms in rodents. Taken together, it is proposed that PA may be useful for the treatment of sleep disturbed subjects with insomnia.
Dual orexin receptor antagonists (DORAs) induce sleep by blocking orexin 1 and orexin 2 receptor-mediated activities responsible for regulating wakefulness. DORAs represent a potential alternative mechanism to the current standard of care that includes the γ-aminobutyric acid (GABA)A receptor positive allosteric modulators, eszopiclone and zolpidem. The present work employs an innovative method to analyze electroencephalogram (EEG) spectral frequencies within sleep/wake states to differentiate the effects of GABAA modulators from DORA-22, an analog of the DORA MK-6096, in Sprague-Dawley rats. The effects of low, intermediate, and high doses of eszopiclone, zolpidem, and DORA-22 were examined after first defining each compound's ability to promote sleep during active-phase dosing. The EEG spectral frequency power within specific sleep stages was calculated in 1 Hz intervals from 1-100 Hz within each sleep/wake state for the first 4 h post-dose. Eszopiclone and zolpidem produced marked, dose-responsive disruptions in sleep stage-specific EEG spectral profiles compared with vehicle treatment. In marked contrast, DORA-22 exhibited marginal changes in the spectral profile, observed only during rapid eye movement (REM) sleep, and only at the highest dose tested. Moreover, while eszopiclone- and zolpidem-induced changes persisted into the subsequent inactive period, the EEG spectral responses to DORA-22 were absent during this phase. These results suggest that DORA-22 differs from eszopiclone and zolpidem whereby DORA-22 promotes somnolence without altering the neuronal network EEG activity observed during normal sleep.Neuropsychopharmacology accepted article preview online, 31 May 2013; doi:10.1038/npp.2013.139.
Chinese herbal medicine (CHM) has been commonly used for treating insomnia in Asian countries for centuries. The aim of this study was to conduct a large-scale pharmaco-epidemiologic study and evaluate the frequency and patterns of CHM use in treating insomnia. We obtained the traditional Chinese medicine (TCM) outpatient claims from the National Health Insurance in Taiwan for the year 2002. Patients with insomnia were identified from the diagnostic code of International Classification of Disease among claimed visiting files. Corresponding prescription files were analyzed, and an association rule was applied to evaluate the co-prescription of CHM. Results showed that there were 16 134 subjects who visited TCM clinics for insomnia in Taiwan during 2002 and received a total of 29 801 CHM prescriptions. Subjects between 40 and 49 years of age comprised the largest number of those treated (25.3%). In addition, female subjects used CHMs for insomnia more frequently than male subjects (female : male = 1.94 : 1). There was an average of 4.8 items prescribed in the form of either an individual Chinese herb or formula in a single CHM prescription for insomnia. Shou-wu-teng (Polygonum multiflorum) was the most commonly prescribed single Chinese herb, while Suan-zao-ren-tang was the most commonly prescribed Chinese herbal formula. According to the association rule, the most commonly prescribed CHM drug combination was Suan-zao-ren-tang plus Long-dan-xie-gan-tang, while the most commonly prescribed triple drug combination was Suan-zao-ren-tang, Albizia julibrissin, and P. multiflorum. Nevertheless, further clinical trials are needed to evaluate the efficacy and safety of these CHMs for treating insomnia.
Using a competitive polymerase chain reaction assay, we have quantitated the absolute amounts of mRNA encoding 14 distinct subunits of the gamma-aminobutyric acid type A (GABAA) receptor in primary cultures of rat cerebellar granule neurons and cerebellar astrocytes. We found that the total amount of GABAA receptor subunit mRNA in astrocytes was 2 orders of magnitude lower than in neuronal cells. Furthermore, granule cell cultures expressed all 14 different GABAA subunit mRNAs, while the astroglial cultures contained detectable amounts of all the subunits expressed by granule cells except the alpha 6 and the gamma 2L subunits. Of the alpha subunit family members, the alpha 1, alpha 5, and alpha 6 mRNAs were prominent in granule cells, while the alpha 1 and alpha 2 mRNAs were abundant in astrocytes. Of the beta receptor subunit mRNAs, the beta 1 and beta 3 mRNAs were abundantly expressed in both cultures. The gamma 2S and gamma 2L mRNAs constituted the great majority of gamma subunit mRNAs in neurons, while the gamma 1 subunit mRNA was the most abundant gamma subunit mRNA in astrocytes. When various allosteric modulators of GABAA receptors were tested electrophysiologically, methyl 6,7-dimethoxy-4-ethyl-beta-carboline- 3-carboxylate (DMCM) was the only one to modulate chloride currents elicited by GABA in a significantly different manner in granule cells (negative modulation) compared with astrocytes (positive modulation). The latter effect was previously observed in transiently expressed recombinant GABAA receptors containing a gamma 1 instead of a gamma 2 subunit. Our quantitative mRNA results suggest that an important molecular determinant responsible for the DMCM-positive modulatory effect on astroglial native GABAA receptors is the presence of the gamma 1 subunit in the receptor assembly.
Two isoforms of glutamic acid decarboxylase (GAD67 and GAD65) and their mRNAs were localized in the rat brain by immunohistochemistry and nonradioactive in situ hybridization methods with digoxigenin-labeled cRNA probes. In most brain regions, both GAD isoforms were present in neuronal cell bodies as well as axon terminals. A few populations of neurons, such as those in the reticular nucleus of the thalamus, exhibited similar cell body labeling for both GADs. However, in many brain regions, the cell bodies that were immunoreactive for GAD67 were often more numerous than those that were immunoreactive for GAD65. In contrast, the density (quantity) of GAD65-immunoreactive axon terminals was higher than that of GAD67-immunoreactive terminals. Strong parallels were observed between the intensity of immunohistochemical labeling of cell bodies and the levels of mRNA labeling for both GAD isoforms. Many groups of GAD-containing cell bodies were distinctly labeled for GAD67, and these same groups of neurons were heavily labeled for GAD67 mRNA. Such neurons included Purkinje cells of the cerebellar cortex, nonpyramidal cells in the cerebral cortex, and neurons of the reticular nucleus of the thalamus. Similar parallels in labeling were observed for GAD65 and its mRNA. Distinct cell body labeling for the protein and associated high levels of GAD65 mRNA were found in neurons of the reticular nucleus of the thalamus and periglomerular cells in the olfactory bulb. However, many cell bodies were not readily labeled for GAD65 with immunohistochemical methods. Such absence or weakness of cell body labeling for the protein was associated with low or moderate levels of GAD65 mRNA. Even though light cell body staining was frequently observed for GAD65 and its mRNA, strong axon terminal labeling for GAD65 was present. Thus, in the deep cerebellar nuclei to which the Purkinje cells of the cerebellar cortex project, strong terminal labeling was observed for both GAD isoforms even though only light cell body labeling of the Purkinje cells was obtained for GAD65 and its mRNA. The findings suggest that the two isoforms of GAD are present in most classes of GABA neurons but that they are not similarly distributed within the neurons. GAD67 is present in readily detectable amounts in many GAD-containing cell bodies whereas GAD65 is particularly prominent in many axon terminals. In addition, neurons that express either form of GAD mRNA also express the corresponding protein. Levels of labeling for the GAD mRNAs suggest that, under normal conditions, the synthesis of GAD65 is frequently lower than that of GAD67.(ABSTRACT TRUNCATED AT 400 WORDS)
Rat EEG has been empirically divided in bands that frequently do not correspond with EEG generators nor with the functional meaning of EEG rhythms.
Power spectra from wakefulness (W), slow-wave sleep (SWS), and paradoxical sleep (PS) of Wistar rats were submitted to Principal Component Analyses (PCA) to investigate which frequencies are covariant.
Three independent eigenvectors were identified for SWS: a band between 1–6, an intermediate band between 7–15, and a fast band between 16–32 Hz (90.74% of the variance); two independent eigenvectors were extracted for PS: slow frequencies between 1-6 covarying together with frequencies between 11–16 Hz, and activity between 6–10 covarying together with fast frequencies between 17–32 Hz (80.38% of the variance); four eigenvectors were obtained for W: 3–7, 8-9, 10–21 and 21–32 Hz (81.47% of the variance). Vigilance states showed significant differences in AP from 1 to 22 Hz.
PCA extracted broad bands different for each vigilance state, which included the most representative EEG activities characteristic of them. These results indicate that during SWS, slow oscillations include frequencies up to 6 Hz, and spindle oscillations frequencies down to 7 Hz. No alpha frequencies were identified as an independent band. Frequencies within theta and beta were gathered in the same eigenvector during PS and in different eigenvectors during W suggesting coordinated activation of hippocampal and cortical systems during PS. These bands are consistent with the underlying neurophysiological mechanisms of sleep and wakefulness and with firing frequencies of generators of rhythmic activity obtained in cellular studies in animals.
To evaluate the level of evidence regarding the safety and efficacy of nonprescription therapies used for insomnia.
Members of the American Academy of Sleep Medicine's Clinical Practice Review Committee.
A search of the World Wide Web was conducted using the terms insomnia, herbal remedies, and alternative treatments to develop a list of therapies. Therapies in this review include passionflower, valerian, Jamaican dogwood, hops, California poppy, chamomile, lemon balm, St. John's wort, kava kava, wild lettuce, scullcap, Patrinia root, first-generation histamine-1-receptor antagonists, alcohol, calcium, vitamin A, nicotinamide, magnesium, vitamin B12, I-tryptophan, 5-hydroxytryptophan, dietary changes, Natrum muriaticum, and Yoku-kan-san-ka-chimpi-hange. A search of the PubMed database was conducted in October 2002 using MeSH terms insomnia and each product listed in this paper, including only articles published in English between 1980 and 2002. Additional relevant articles from reference lists were also reviewed. Given the paucity of pediatric publications, this age group was excluded from this review.
Although randomized, placebo-controlled studies were available for a few compounds, rigorous scientific data supporting a beneficial effect were not found for the majority of herbal supplements, dietary changes, and other nutritional supplements popularly used for treating insomnia symptoms. Nevertheless, such treatments are described as alternative remedies for insomnia. Studies are limited by small numbers of participants and, in some instances, inadequate design, lack of statistical analysis, and sparse use of objective measurements. Sparse or no scientific data were found to support the efficacy of most products as hypnotics, including chamomile and St. John's wort. There is preliminary but conflicting evidence suggesting Valerian officinalis L. and first-generation histamine-1-receptor antagonists have efficacy as mild hypnotics over short-term use. There are significant potential risks associated with the use of Jamaican dogwood, kava kava, alcohol, and I-tryptophan. Physicians may find this information useful in counseling their patients.
The fruits of Schisandra chinensis have been used for the treatment of insomnia in oriental countries for more than thousands years. However, the pharmacological properties and the mechanism of sedative and hypnotic effects have not yet been studied. Gomisin N is one of the major bioactive constituents from the fruits of Schisandra chinensis, and in this paper we reported a detailed study on the effects and mechanisms of Gomisin N on its sedative and hypnotic activity for the first time. These results implied that Gomisin N possessed weak sedative effects on locomotion activity in normal mice, and produced a dose-dependent(5-45mg/kg, i.p.) increase in sleep duration in pentobarbital-treated mice, thus, itself did not induce sleep at higher dose which was used in this experiment (45mg/kg, i.p.). It also can reverse the rodent models of insomnia induced by p-chlorophenylalanine (PCPA) and caffeine, which could exhibite a synergistic effect with 5-hydroxytryptophan (5-HTP) as well, furthermore, hypnotic effects of Gomisin N was inhibited by flumazenil (a specific GABAA-BZD receptor antagonist). Altogether, these results indicated that Gomisin N produced beneficial sedative and hypnotic bioactivity, which might be mediated by the modification of the serotonergic and GABAergic system.
A new lignan, (7'S,8S,8'S)-3,5'-dimethoxy-3',4,9'-trihydroxy-7',9-epoxy-8,8'-lignan, named vibruresinol (1), was isolated from the stems of Viburnum erosum by silica gel, ODS, and Sephadex LH-20 column chromatography. In addition, four other known lignans, (7'R,8S,8'S)-3,5'-dimethoxy-3',4,8',9'-tetrahydroxy-7',9-epoxy-8,8'-lignan (2), (+)-syringaresinol (3), (+)-pinoresinol (4), and (+)-pinoresinol-4-O-β-D-glucopyranoside (5), and five known neolignans, herpetol (6), vibsanol (7), (-)-dehydrodiconiferyl alcohol (8), icariside E4 (9), and dihydrodehydrodiconiferyl alcohol (10), were isolated in the same manner. The chemical structures of the compounds were determined based on spectroscopic data including NMR, MS, and IR. All of the compounds described above were isolated from V. erosum for the first time. The isolated compounds 3, 4, and 6 were evaluated for neuroprotective activity on glutamate-induced cell death in HT22 cells and had EC50 values of 6.33 ± 1.22, 6.96 ± 0.65, and 9.15 ± 0.36 μM, respectively. Likewise, the same compounds had inhibitory activity on NO production in LPS-induced RAW 264.7 cells with IC50 values of 8.30 ± 1.56, 7.89 ± 1.22, and 9.32 ± 0.36 μM, respectively.
Four flavanonols (1–4), one xanthone (5), and three flavonoid glycosides (6–8), were isolated from the leaves and stems of Desmodium caudatum. Their structures were elucidated by comparing spectroscopic data with reported values. The anti-inflammatory activity of the isolated compounds was investigated in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells. Among them, compounds 1 and 2 exhibited inhibitory effects on LPS-induced IL-6, IL-12 p40, and TNF-α production with IC50 values ranging from 6.0 to 29.4 μM. Compound 5 exhibited 1,1-diphenyl-2-picrylhydrazyl radical and intracellular reactive oxygen species scavenging activity in human HaCaT keratinocytes. These results warrant further studies of the potential anti-inflammatory and antioxidant benefits of compounds from D.
caudatum.
These experiments were performed to investigate whether 3,4,5-trimethoxycinnamic acid (TMCA), one of the constituents derived from Polygalae Radix, enhances pentobarbital-induced sleeping behaviors, and to alter sleep architecture through the γ-aminobutyric acid (GABA)ergic systems in mice. TMCA decreased the locomotor activity. TMCA prolonged total sleep time, and reduced sleep latency induced by pentobarbital, similar to muscimol, a GABAA agonist. From the electrocencephalogram recording for 6 h after TMCA administration, the number of sleep/wake cycles were reduced by TMCA. TMCA also increased the total sleep time and non-rapid eye movement (NREM) sleep. In addition, TMCA increased Cl(-) influx in primary cultured cerebellar granule cells of mice. TMCA increased the activation of glutamic acid decarboxylase (GAD) and the expressions of γ-subunit of GABAA receptors in the cerebellar granule cells. However, α- and β-subunits proteins of GABAA receptors were not increased. Therefore, TMCA would increase pentobarbital induced-sleep and NREM sleep in mice. These results indicate that TMCA may enhance sleep and alter sleep architecture through GABAAergic systyems.
The hydroalcoholic extract of Poria cocos and two lanostane derivatives isolated from it, pachymic acid (1) and dehydrotumulosic acid (2), were active as inhibitors of phospholipase A2 from snake venom when a polarographic method was used. Dehydrotumulosic acid exhibited an IC50 of 0.845 mM. These two compounds are structurally related to certain triterpenoids from Ganoderma and Schinus that have previously been described as competitive inhibitors of phospholipase A2. These comprise a new group of natural potential antiinflammatory agents due to their interaction with that enzyme.
Pachymic acid, 3-O-acetyl-16 α-hydroxytrametenolic acid, and poricoic acid B had been isolated from the sclerotium of Poria cocos Wolf. These compounds showed a strong inhibitory activity against 12-O-tetradecanoylphorbol-13-acetate-induced inflammation in mice. At 0.2 μmol/mouse, these compounds markedly inhibited the promoting effect of 12-O-tetradecanoylphorbol-13-acetate (1 μg/mouse) on skin tumor formation following initiation with 7,12-dimethylbenz[a]anthracene (50 μg/mouse).Copyright © 1996 S. Karger AG, Basel
Studies of the GABA-synthetic enzyme glutamate decarboxylase (glutamic acid decarboxylase; GAD; E.C.4.1.1.15) began in 1951 with the work of Roberts and his colleagues. Since then, many investigators have demonstrated the structural and functional heterogeneity of brain GAD. At least part of this heterogeneity derives from the existence of two GAD genes.
A prolonged-release formulation of melatonin (PR-M) is indicated for insomnia in patients aged 55 years and older. Because hypnotics result in impairments of body sway, it was important to evaluate the effect of 2 mg PR-M on postural stability in older adults at night.
Twenty-four healthy volunteers (12 women, 12 men, aged 55-64 years) completed a randomized, double-blind, single-dose, three-way crossover study of postural stability of PR-M 2 mg, zolpidem 10 mg (active control) or placebo. Subjects were tested for body sway 30 min before, 1.5 and 4 h after dosing. Parameters tested were the area of the 95% confidence ellipse enclosing the center of pressure (COP; [A95]) and COP path length.
Zolpidem significantly increased the A95 (both eyes conditions at all time points) and path length of COP. PR-M had no effect on A95 (both "eyes closed" and "eyes open" conditions at all time points) compared with placebo and increased COP path length by 10% at 4 h post-dose in open but not closed eyes condition. No serious adverse events were observed.
In older adults, evening PR-M intake did not impair postural stability during the night. The postural instability with zolpidem demonstrated assay sensitivity and validated the outcome.
Ganoderma lucidum (Ling Zhi) is a basidiomycete white-rot macrofungus that has been used as a tranquilizing agent (i.e., An-Shen effect) for the treatment of restlessness, insomnia, and palpitation in China for hundreds of years.
The present study aimed to investigate whether Ganoderma lucidum extract (GLE) influences the sleep of freely moving rats and the potential mechanism.
Ganoderma lucidum extract was extracted from fruiting bodies of Ganoderma lucidum. Rats were treated with GLE orally for 3 days, and on the third day, electroencephalographic and electromyographic recordings were made for 6h from 9:00 p.m. to 3:00 a.m. in freely moving rats. Sleep parameters were analyzed using SleepSign software. Tumor necrosis factor-α (TNF-α) levels were measured using the enzyme-linked immunosorbent assay.
Three-day administration of GLE significantly increased total sleep time and non-rapid eye movement (NREM) sleep time at a dose of 80 mg/kg (i.g.) without influencing slow-wave sleep or REM sleep in freely moving rats. TNF-α levels were significantly increased concomitantly in serum, the hypothalamus, and dorsal raphe nucleus. The hypnotic effect of GLE (80 mg/kg, i.g.) was significantly inhibited by intracerebroventricular injection of TNF-α antibody (2.5 μg/rat). Co-administration of GLE (40 mg/kg, i.g.) and TNF-α (12.5 ng/rat, i.c.v.), both at ineffective doses, revealed an additive hypnotic effect.
These results suggest that GLE has hypnotic effects in freely moving rats. The mechanism by which the extract promoted sleep remains unclear, but this effect appears to be primarily related to the modulation of cytokines such as TNF-α. Furthermore, these data at least partially support the ethnomedical use of Ganoderma lucidum.
Zolpidem is a hypnotic which acts at the GABAA receptor and is indicated for short-term insomnia. Sleep related disorders including somnambulism, sleep related eating and sleep-driving have been reported with zolpidem. A 51-year-old insomniac who used zolpidem 10 mg nightly starting at 44 years of age is described. A few weeks after starting zolpidem she began walking, eating, and had one episode of driving while asleep. Episodes of sleep related eating, sleepwalking, and sleeptalking occurred 3 nights per week, 1 to 2 h after sleep onset. After her evaluation, the patient's zolpidem was gradually discontinued, and all sleep related activities immediately ceased. An 18F-FDG-PET was obtained 2 months after discontinuation of zolpidem. The following day, FDG was administered 1 h after oral administration of 10 mg zolpidem, and then a second PET was performed. We report the results and a review of the literature regarding other unintended effects seen with zolpidem use.
Sleep EEG in the sigma and delta frequency bands was subjected to spectral analysis in 8 normal young adults. In each subject, power density of sigma and delta oscillated reciprocally during NREM sleep, confirming an observation made initially with period/amplitude analysis. In REM sleep, power density for both frequency bands was at its lowest levels. Correlation coefficients between power density of delta vs. 1/sigma for all artifact-free 20-s epochs of NREM sleep/night were highly significant for each subject. These results show that cyclic oscillation of EEG within sleep is not limited to delta frequencies. The reciprocal relation of sigma to delta holds implications for the EEG mechanisms of NREM sleep. This dynamic pattern may also prove useful for sleep stage scoring and for a finer empirical analysis of sleep in psychiatric and neurological disorders.
Craniometric and stereotaxic data from rats of different sex, strain and weight were compared. It was found that stereotaxic atlases can be used with rats of different sex and strain provided that the weights of the rats conform to those used in the reference atlas. If rats of different weights are used, greater accuracy can be achieved if bregma is used as the reference point for work with rostral structures and the interaural line for work with caudal structures.
Pachymic acid, 3-O-acetyl-16 alpha-hydroxytrametenolic acid, and poricoic acid B had been isolated from the sclerotium of Poria cocos Wolf. These compounds showed a strong inhibitory activity against 12-O-tetradecanoylphorbol-13-acetate-induced inflammation in mice. At 0.2 mumol/mouse, these compounds markedly inhibited the promoting effect of 12-O-tetradecanoylphorbol-13-acetate (1 microgram/mouse) on skin tumor formation following initiation with 7,12-dimethylbenz[a]anthracene (50 micrograms/mouse).
The triterpenes isolated from P. cocos and their derivatives were examined for anti-emetic activity. Some of these triterpenes inhibited emetic action induced by oral administration of copper sulfate pentahydrate to leopard frog. The triterpenes having an exomethylene group at C-24 showed anti-emetic activity to frogs.
A microplate chloride ion channel assay, using N-(6-methoxyquinolyl) acetoethyl ester (MQAE) fluorescence changes has been developed. Forskolin stimulation of T84 cells caused cAMP-dependent, increased Cl- loss. Forskolin responses after 6 min gave an EC50 of 0.27 +/- 0.05 microM, illustrating the reproducibility of the assay. Forskolin exposure of CFPAC-1 cells, containing delta F508 CFTR, and CFPAC-1 PLJ4.7 cells, transfected with WT-CFTR stimulated Cl- secretion only from the latter, showing that the assay can be used to measure CFTR function. Stimulation of CFPAC-1 cells with ionomycin increased Cl- efflux, demonstrating functional Ca(2+)-mediated Cl- secretion in these cells. Ionomycin also induced a dose-responsive Cl- efflux from T84 cells that, unlike the forskolin response, was Ca2+ dependent. Removal of Na+ ions severely inhibited basal and stimulated Cl- efflux from T84 cells. However, furosemide did not affect forskolin-stimulated JCl, although the magnitude of the Cl- loss was reduced. The Stern-Volmer constant for MQAE fluorescence in T84 cells was calculated as 28.3 +/- 0.9 M-1 and the [Cl-]i in untreated T84 cells was determined as 52.4 +/- 0.6 mM. Stimulation of T84 cells with ionomycin and forskolin before inducing Cl- efflux allowed calculation of initial efflux rates without interference by second messenger generation and ion channel activation kinetics.
The study presented here compared the acute performance-impairing, subject-rated, and observer-rated effects of quazepam (15, 30, and 45 mg), triazolam (0.1875, 0.375, and 0.5625 mg), zolpidem (7.5, 15, and 22.5 mg), and placebo in nine healthy, non-drug-abusing humans. Quazepam, a trifluoroethylbenzodiazepine, was chosen for study because, when compared with triazolam, a triazolobenzodiazepine, it is a relatively weak benzodiazepine-receptor ligand, and it may bind selectively to the BZ1 benzodiazepine-receptor subtype. Zolpidem, an imidazopyridine, is the most commonly prescribed hypnotic and was chosen for study because it is biochemically distinct from benzodiazepine hypnotics and also purportedly binds selectively to the BZ1 benzodiazepine-receptor subtype. Triazolam was chosen as the reference compound because it binds nonselectively to BZ1 and BZ2 benzodiazepine-receptor subtypes. Triazolam, zolpidem, quazepam, and placebo were administered orally in a double-blind, crossover design. Triazolam and zolpidem produced orderly dose- and time-related impairment of learning, performance, and recall, and produced sedative-like subject- and observer-rated drug effects. The behavioral pharmacologic profile of zolpidem and triazolam was indistinguishable in that at peak effect, the absolute magnitude of drug effect was comparable across the various measures. Quazepam, by contrast, did not impair performance on any task to a statistically significant degree, nor did it produce significant sedation as measured by subject- and observer-rated drug-effect questionnaires. Whether these effects are a result of the unique benzodiazepine-receptor binding profile of quazepam or the testing of insufficient dosages is unknown. Future research could extend the findings presented here by testing higher dosages of quazepam.
Pachymic and dehydrotumulosic acids were studied in different models of acute and chronic inflammation. They proved to be active in most of the methods applied. None of them were active against arachidonic acid-induced ear edema. Dehydrotumulosic acid significantly diminished the mouse ear edema induced by ethyl phenylpropiolate, while pachymic acid was ineffective. When the putative corticoid-like mechanism of both compounds was explored, pachymic acid activity was partially abolished by the glucocorticoid receptor antagonist progesterone, but dehydrotumulosic acid activity was not affected. In vivo experiments demonstrated the inhibition by both principles of the phospholipase A2 (PLA2)-induced extravasation. The previous report on the effects of both compounds in vitro against PLA2, together with the present in vivo results, support the idea that the inhibition of this enzyme probably constitutes their main mechanism of action.
Abbreviations
AA:arachidonic acidCOX:cyclooxygenaseEPP:ethyl phenylpropiolateLOX:lipoxygenaseMPO:myeloperoxidasePLA2:phospholipase A2PMNL:polymorphonuclear leukocytesTPA:12-O-tetradecanoylphorbol-13-acetate
Rat cerebellar granule cells were cultured for 5 days with progesterone, resulting in the conversion of progesterone to allopregnanolone, a potent and efficacious modulator of gamma-aminobutyric acid (GABA) type-A receptors, as well as in decreases in the abundance of GABA(A) receptor alpha(1), alpha(3), alpha(5), and gamma(2) subunit mRNAs. These effects were accompanied by decreases in the efficacies of diazepam and the beta-carboline DMCM with regard to modulation of GABA-evoked Cl(-) currents. Withdrawal from such progesterone treatment resulted in a rapid and selective increase in the abundance of the GABA(A) alpha(4) subunit mRNA that was associated with a restoration of receptor sensitivity to the negative modulatory action of DMCM, a positive receptor response to flumazenil, and continued reduced responsiveness of receptors to diazepam. Prevention of allopregnanolone synthesis by the 5alpha-reductase inhibitor finasteride also prevented the changes in both GABA(A) receptor gene expression and receptor function elicited by progesterone treatment and withdrawal.
Insomnia is the most common sleep disorder, and is often associated with significant medical, psychological, and social disturbances. Conventional medical treatment for insomnia includes psychological and pharmacological approaches; however, long-term use of frequently prescribed medications can lead to habituation and problematic withdrawal symptoms. Therefore, herbal and other natural sleep aids are gaining popularity, as herbs commonly used for their sedative-hypnotic effects do not have the drawbacks of conventional drugs. Whether alternative therapies possess activity similar to conventional therapies needs further evaluation.
The aim of this study was to develop a sleep-wake recording system for rats that would yield results more comparable to those obtained from cats than those that are usually reported. For 18 male Sprague-Dawley rats, the authors combined measures of cortical and hippocampal electroencephalogram (EEG) and neck muscle electromyogram with the electrooculogram and pontine EEG, so that the behavioral states could be identified with greater confidence with the use of polygraphic criteria developed in the cat and so that the distinctive phasic events of REM sleep could be more easily studied in the rat. The results suggest that for many neurophysiological studies, the rat is a suitable alternative to the cat.
Benzodiazepine (BZD) potentiation of GABA-activated Cl(-)-current (I(GABA)) in recombinant GABA(A) receptors requires the presence of the gamma subunit. When alpha1, beta2 and gamma2S cRNA are expressed in a 1:1:1 ratio in Xenopus oocytes, BZD potentiation of I(GABA) is submaximal, variable and diminishes over time. Potentiation by BZDs is increased, more reproducible and is stabilized over time by increasing the relative amount of cRNA coding for the gamma2S subunit. In addition, GABA EC(50) values for alpha1beta2gamma2 (1:1:1) receptors are intermediate to values measured for alpha1beta2 (1:1) and alpha1beta2gamma2 (1:1:10) receptors. We conclude that co-expression of equal ratios of alpha1, beta2 and gamma2 subunits in Xenopus oocytes produces a mixed population of alpha1beta2 and alpha1beta2gamma2 receptors. Therefore, for accurate measurements of BZD potentiation it is necessary to inject a higher ratio of gamma2 subunit cRNA relative to alpha1 and beta2 cRNA. This results in a purer population of alpha1beta2gamma2 receptors.
We show that PCSC, a polysaccharide isolated from the sclerotium of Poria cocos with 1% sodium carbonate, significantly induces nitric oxide (NO) production and inducible NO synthase (iNOS) transcription through the activation of nuclear factor-kappaB/Rel (NF-kappaB/Rel). In vivo administration of PCSC induced NO production by peritoneal macrophages of B6C3F1 mice. PCSC also dose-dependently induced the production of NO in isolated mouse peritoneal macrophages and RAW 264.7, a murine macrophage-like cell line. Moreover, iNOS protein and mRNA transcription were strongly induced by PCSC in RAW 264.7 cells. To further investigate the mechanism responsible for the induction of iNOS gene expression, we investigated the effect of PCSC on the activation of transcription factors including NF-kappaB/Rel and Oct, whose binding sites were located in the promoter of iNOS gene. Treatment of RAW 264.7 cells with PCSC produced strong induction of NF-kappaB/Rel-dependent reporter gene expression, whereas Oct-dependent gene expression was not affected by PCSC. DNA binding activity of NF-kappaB/Rel was significantly induced by PCSC, and this effect was mediated through the degradation of IkappaBalpha. In conclusion, we demonstrate that PCSC stimulates macrophages to express iNOS gene through the activation of NF-kappaB/Rel.
GABAA receptors are molecular substrates for the regulation of vigilance, anxiety, muscle tension, epileptogenic activity, and memory functions, and the enhancement of GABAA receptor-mediated fast synaptic inhibition is the basis for the pharmacotherapy of various neurological and psychiatric disorders. Two kinds of GABAA receptor-targeted mutant mice have been generated: (a) knockout mice that lack individual GABAA receptor subunits (alpha1, alpha5, alpha6, beta2, beta3, gamma2, delta, and rho1) and (b) knockin mice that carry point mutations affecting the action of modulatory drugs [alpha1(H101R), alpha2(H101R), alpha3(H126R), alpha5(H105R), and beta3(N265M)]. Whereas the knockout mice have provided information primarily with respect to the regulation of subunit gene transcription, receptor assembly, and some physiological functions of individual receptor subtypes, the point-mutated knockin mice in which specific GABAA receptor subtypes are insensitive to diazepam or some general anesthetics have revealed the specific contribution of individual receptor subtypes to the pharmacological spectrum of diazepam and general anesthetics.
In the brain, highly connected and heterogeneous GABAergic cells are crucial in controling the activity of neuronal networks. They accomplish this task by communicating through remarkably diverse sets of inhibitory processes, the complexity of which is reflected by the variety of interneuron classification schemes proposed in recent years. It is now becoming clear that the subcellular localization and intrinsic properties of heteropentameric GABA(A) receptors themselves also constitute major sources of diversity in GABA-mediated signaling. This review summarizes some of the factors underlying this diversity, including GABA(A) receptor subunit composition, localization, activation, number and phosphorylation states, variance of GABA concentration in the synaptic cleft, and some of the presynaptic factors regulating GABA release.
The bioactivity-guided fractionation of the methylene chloride extract of the sclerotium of Poria cocos led to the isolation of (S)-(+)-turmerone (1), ergosterol peroxide (2), polyporenic acid C (3), dehydropachymic acid (4), pachymic acid (5), and tumulosic acid (6). Compounds 4-6 exhibited moderate cytotoxicities, with IC50 values of 20.5, 29.1, and 10.4 microM, respectively, against a human colon carcinoma cell line. However, 3-6 not only showed inhibitory activities as potent as etoposide used as a positive control on DNA topoisomerase II (36.1, 36.2, 43.9 and 66.7% inhibition at a concentration of 20 microM, respectively), but also inhibition of DNA topoisomerase I (55.8, 60.7, 43.5, and 83.3% inhibition at a concentration of 100 microM, respectively).
Pachymic acid (PA) is a natural triterpenoid known to inhibit the phospholipase A2 (PLA(2)) family of arachidonic acid (AA)-producing enzymes. PLA(2) is elevated in prostatic adenocarcinoma and conversion of AA to prostaglandins leads to AKT pro-survival activity. In this study, we investigated the effect of PA on the growth of human prostate cancer cells. PA significantly reduced cell proliferation and induced apoptosis in a dose- and time-dependent fashion, with androgen-insensitive DU145 prostate cancer cells showing greater growth inhibition relative to androgen-responsive LNCaP. Despite elevated protein expression of the cell cycle inhibitor, p21, apoptosis occurred in the absence of cell cycle arrest. PA-treatment decreased Bad phosphorylation, increased Bcl-2 phosphorylation, and activated caspases-9 and -3, suggesting that PA initiated apoptosis through mitochondria dysfunction. PA-treatment also decreased the expression and activation of proteins within the AKT signal pathway. We speculate that PA influenced apoptosis by reducing prostaglandin synthesis and AKT activity.
This work presents behavioral effects of yangambin isolated from the leaves of Ocotea duckei on open field, rota rod, barbiturate sleeping time, forced swimming and elevated plus maze test in mice. Yangambin was intraperitoneally administered to male mice at single doses of 12.5, 25 and 50 mg/kg. The results showed that yangambin in the doses of 25 and 50 mg/kg decreased the locomotor activity and the number of rearing. However, no change was observed in the rota rod test between the yangambin groups as compared to the control group. Reduction on the sleep latency and a prolongation of the sleeping time induced by pentobarbital was observed only with the yangambin dose of 50 mg/kg. In the forced swimming test, yangambin (25 and 50 mg/kg) increased the immobility time. Yangambin, in the doses of 25 and 50 mg/kg, decreased the number of entries and the time of permanence in the open arms of the elevated plus maze test. However, this effect can not be related to anxiogenic effects, but to a decrease in locomotor activity. The results showed that yangambin presents a depressant activity in the open field, forced swimming and pentobarbital sleeping time tests. These effects probably were not due to peripheral neuromuscular blockade, since there was no alteration on the rota rod test. Also, no anxiolytic effect was observed after the treatment with yangambin.
The functions of mammalian sleep remain unclear. Most theories suggest a role for non-rapid eye movement (NREM) sleep in energy conservation and in nervous system recuperation. Theories of REM sleep have suggested a role for this state in periodic brain activation during sleep, in localized recuperative processes and in emotional regulation. Across mammals, the amount and nature of sleep are correlated with age, body size and ecological variables, such as whether the animals live in a terrestrial or an aquatic environment, their diet and the safety of their sleeping site. Sleep may be an efficient time for the completion of a number of functions, but variations in sleep expression indicate that these functions may differ across species.
It is increasingly being appreciated that GABAA receptor subtypes, through their specific regional, cellular and subcellular localization, are linked to distinct neuronal circuits and consequently serve distinct functions. GABAA receptor subtype-selective drugs are therefore expected to provide novel pharmacological profiles. Receptors containing the alpha1 subunit mediate sedation and serve as targets for sedative hypnotics. Agonists selective for alpha2- and/or alpha3-containing GABAA receptors have been shown to provide anxiolysis without sedation in preclinical models, whereas inverse agonists selective for alpha5-containing GABAA receptors provide memory enhancement. Agonists selective for alpha3-containing GABAA receptors might be suitable for the treatment of deficits in sensorimotor processing in psychiatric disorders. Thus, a new pharmacology based on GABAA receptor subtype-specific actions is emerging.
The amygdala has been implicated in emotional arousal and in the regulation of sleep. Previously, we demonstrated that tetrodotoxin (TTX), a sodium channel blocker that temporarily inactivates neurons and tracts, microinjected into the central nucleus of the amygdala (CNA) during the light period significantly reduced REM, shortened sleep latency, and increased EEG delta power in rats. TTX inactivation of CNA also reduced activity in the open field. These findings suggest that the amygdala modulates arousal in a variety of situations. To test the hypothesis that the amygdala may influence spontaneous arousal, we examined the effects of TTX inactivation of CNA on sleep and activity during the dark period when rats show higher arousal and less sleep. EEG and activity were recorded via telemetry in Wistar rats (n = 8). Bilateral microinjections of TTX (L: 2.5 ng/0.1; H: 5.0 ng/0.2 microl) or SAL (saline, 0.2 microl) were administered before lights off followed by recording throughout the 12-h dark period and following 12-h light period. Microinjections were given at 5-day intervals and were counterbalanced across condition. TTX significantly shortened sleep latency, increased NREM time, decreased REM time, and decreased activity. TTX increased NREM episode duration, whereas the number and duration of REM episodes were decreased. The present results indicate that TTX inactivation of CNA can increase NREM time when spontaneous arousal is high, suggesting a broad role for the amygdala in regulating arousal. The results suggest that understanding the ways in which the amygdala modulates arousal may provide insight into the mechanisms underlying altered sleep in mood and anxiety disorders.
Many questions remain unanswered with regard to our understanding of insomnia. Although it is generally believed that 10% to 15% of the adult population suffers from chronic insomnia, and an additional 25% to 35% have transient or occasional insomnia, prevalence estimates vary because of inconsistent definitions and diagnostic criteria. The elderly in particular are affected by insomnia, and it has been shown that women are more likely to have sleep difficulties than men. Although insomnia can be a primary condition, and can coexist with other disorders or be considered secondary to these disorders, the mechanisms producing it are not clearly defined. Additionally, the relationship between insomnia and other disease states is not always clear because it is often not possible to determine the cause-and-effect relationship between disorders. Epidemiologic studies show that abnormal sleep patterns predict lower life expectancy, and that people with insomnia are more likely to develop affective disorders, substance abuse, and other adverse health outcomes. This article will provide an overview of insomnia, its prevalence and epidemiology, and guidelines for clinical assessment.
To assess residual psychomotor and cognitive effects of a modified-release formulation of zolpidem (zolpidem-MR), developed to provide sustained hypnotic efficacy during the whole night, compared with placebo and flurazepam.
Twenty-four healthy elderly volunteers received four study treatments (zolpidem-MR 6.25 mg and 12.5 mg, placebo and flurazepam 30 mg) using a randomized, cross-over, double-blind design. Residual psychomotor and cognitive effects were assessed with a psychometric test battery. Quality of sleep and residual effects were evaluated subjectively with the Leeds Sleep Evaluation Questionnaire.
Psychometric performance was significantly impaired with flurazepam but not with zolpidem-MR at either dose. Ease of falling asleep and sleep quality were significantly improved with both doses of zolpidem-MR and with flurazepam. Neither active drug modified perception of well-being on awakening.
In elderly subjects, zolpidem-MR showed no residual functional impairment in psychometric or cognitive tests sensitive to flurazepam.
Fruits of Fructus Schisandrae have been used as medicine for the treatment for insomnia in traditional Chinese medicine. In the present research, the sedative and hypnotic activities of the ethanol fraction of Fructus Schisandrae fruit (SY3) were studied in mice and rats. In the open field test, SY3 (25, 50 and 100 mg/kg) significantly inhibited the motor activity of mice compared to the normal. Results also showed SY3 potentiated pentobarbital-induced sleep by not only increasing the number of falling asleep and prolonging sleeping time but also reducing sleep latency. Furthermore, sleep-wake stages of rats were evaluated by polytrophic recording for 3 h after treatment. The results demonstrated that SY3 at doses of 20, 40 and 80 mg/kg behaved remarkable action on sleep architecture of rats, which contain the increase of total sleeping time, the rate of deep slow wave sleep (SWS) and mean episode duration of deep SWS, and the decrease of the latency of deep SWS. Therefore, these results suggest that the ethanol fraction of Fructus Schisandrae fruit possesses potent sedative and hypnotic activity, which supported its therapeutic use for insomnia.
Zizyphi Spinosi Semen (ZSS) has been widely used for the treatment of insomnia in oriental countries. This experiment was performed to investigate whether sanjoinine A, one of major alkaloid compounds of ZSS, has hypnotic effects and/or enhances pentobarbital-induced sleeping behaviors through the gamma-aminobutyric acid (GABA)-ergic systems. Sanjoinine A itself did not induce sleeping at the higher dose used in this experiment. However, sanjoinine A prolonged sleeping time and reduced the sleeping latency induced by pentobarbital in a dose-dependent manner similar to muscimol, a GABA(A) receptor agonist. Sanjoinine A also increased sleeping rate and sleeping time when administered combined with pentobarbital at a sub-hypnotic dosage and showed synergistic effects with muscimol in potentiating sleeping onset and enhancing sleeping time induced by pentobarbital. In addition, both sanjoinine A and pentobarbital increased chloride influx in primary cultured cerebellar granule cells. Sanjoinine A also showed similar effects with muscimol in potentiating chloride influx inducing effects of low dose pentobarbital. Sanjoinine A decreased GABA(A) receptor alpha-subunit expression and increased gamma-subunit expression, and had no effects on the abundance of beta-subunits in primary cultured cerebellar granule cells, showing different subunit expression from pentobarbital. In addition, we found that sanjoinine A also enhanced expression of glutamic acid decarboxylase (GAD), but pentobarbital did not. In conclusion, sanjoinine A itself does not induce sleeping, but it augments pentobarbital-induced sleeping behaviors through the modification of GABA-ergic systems.
AR Is there more to GABA than synaptic inhibition
- D F Owens
- Kriegstein
Owens DF, Kriegstein AR. Is there more to GABA than
synaptic inhibition? Nat Rev Neurosci 2002;3:715-727.