Yi-gan San Research Articles

Neurotherapy of Yi-Gan-San, a Traditional Herbal Medicine, in an Alzheimer's Disease Model of Drosophila melanogaster by Alleviating Aβ42 Expression.

Alzheimer’s disease (AD), a main cause of dementia, is the most common neurodegenerative disease that is related to the abnormal accumulation of amyloid β (Aβ) proteins. Yi-Gan-San (YGS), a traditional herbal medicine, has been used for the management of neurodegenerative disorders and for the treatment of neurosis, insomnia and dementia. The aim of this study was to examine antioxidant capacity and cytotoxicity of YGS treatment by using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays in vitro. We explored neuroprotective effects of YGS treatment in alleviating Aβ neurotoxicity of Drosophila melanogaster in vivo by comparing survival rate, climbing index, and Aβ expressions through retinal green fluorescent protein (GFP) expression, highly sensitive immunomagnetic reduction (IMR) and Western blotting assays. In the in vitro study, our results showed that scavenging activities of free radical and SH-SY5Y nerve cell viability were increased significantly (p < 0.01–0.05). In the in vivo study, Aβ42-expressing flies (Aβ42-GFP flies) and their WT flies (mCD8-GFP flies) were used as an animal model to examine the neurotherapeutic effects of YGS treatment. Our results showed that, in comparison with those Aβ42 flies under sham treatments, Aβ42 flies under YGS treatments showed a greater survival rate, better climbing speed, and lower Aβ42 aggregation in Drosophila brain tissue (p < 0.01). Our findings suggest that YGS should have a beneficial alternative therapy for AD and dementia via alleviating Aβ neurotoxicity in the brain tissue.

Effects of Yi-Gan-san on the psychiatric behavior of children and adolescents with Tourette's Syndrome: A randomized, double-blind, controlled preliminary study

Ethnopharmacological relevanceGilles de la Tourette's Syndrome (TS) is a childhood-onset disease with clinical features of motor and phonic tics. Yi-Gan-san (YGS) is a traditional Chinese medicine formula that can reduce aggressiveness and agitation and inhibit dopamine function. This study investigated the effects of YGS on the psychiatric behavior of children and adolescents with TS. MethodsA double-blind, randomized, controlled preliminary study was conducted. A total of 38 patients with TS were assigned to the control group (CG, 19 patients) who received the oral administration of YGS placebo (90% starch and 10% YGS; 2.5 g thrice daily) or to a treatment group (TG, 19 patients) who received YGS for 4 weeks. The primary outcome measure was the change in Yale Global Tic Severity Scale (YGTSS) overall and subscale scores. ResultsThe intensity score for phonic tics before oral administration of YGS, and after 2 weeks, 3 weeks and 4 weeks was not significantly different between CG and TG groups (2.94 ± 1.14 vs 2.79 ± 1.08, p = .686; 2.29 ± 1.21 vs 1.95 ± 1.08, p = .370; 2.41 ± 1.18 vs 2.05 ± 1.51, p = .435; and 2.29 ± 1.26 vs 1.84 ± 1.42, p = .323, respectively), while the intensity score for phonic tics after 1-week oral administration of YGS in the TG was 1.89 ± 1.10 lower than 3.06 ± 1.39 in the CG (p = .008). ConclusionOral administration of YGS for 1 week only reduced the intensity of phonic tics compared with oral administration of YGS placebo, suggesting that YGS can reduce their intensity for a short period, and the compliance of oral administration of YGS for 4 weeks can be accepted in children and adolescents with Tourette's Syndrome. However, because this study was preliminary, the selection of an appropriate placebo and dosage and long-term observations are crucial areas for future studies.

Metabolic profiling deciphering the potential targets of Yi-Gan San against vascular dementia in rat

Vascular dementia (VaD) is widely recognized as the second most common type of dementia, yet effective treatments are still lacking. Traditional Chinese medicine Yi-Gan San (YGS) has potent efficacy on treating VaD in clinical practice. However, the underlying mechanism is still unclear. In the present study, a UPLC-QTOFMS-based metabolomic method was established to explore the therapeutic mechanisms of YGS on VaD. Experimental VaD model was induced by bilateral occlusion of the common carotid arteries (two-vessel occlusion [2-VO]) in rats. Cognitive function, pathological changes and oxidative stress condition in the brains of VaD rats were assessed using Morris water maze tests, hematoxylin-eosin staining and antioxidant assays (MDA, SOD, GSH and GSH-Px), respectively. UPLC-QTOFMS combined with computational systems analysis were conducted to study the changes of metabolic networks in serum of rats. The results indicated that VaD model was established successfully and 2-VO caused a decline in spatial learning and memory and hippocampal histopathological abnormalities of rats. YGS significantly improved the cognitive impairment induced by 2VO and attenuated hippocampal histopathological abnormalities. The inducement of 2-VO significantly elevated the level of MDA, and reduced SOD and GSH-Px activities, and YGS can significantly regulate the levels. We have identified 34 significantly changed metabolites related to 2-VO-induced VaD, and YGS can significantly regulate the abnormalities of 24 metabolites. Metabolic pathway enrichment analysis revealed that the mechanisms of YGS against 2-VO-induced VaD may be attributed to modulating the metabolic disorders of arachidonic acid metabolism, glycerophospholipid metabolism, tryptophan metabolism, and sphingolipid metabolism. The present study provides new experimental information on the pathogenesis of VaD, unravels the potential targeted metabolic pathways of YGS against VaD on the whole metabolic network and highlights the importance of metabolomics as a potential tool for deciphering drug-targeted metabolic pathways.

Outcomes of Inpatient Treatment for Behavioral and Psychological Symptoms of Dementia in Alzheimer's Disease Versus Dementia With Lewy Bodies.

Most community-based studies have shown a more malignant clinical course for patients with dementia with Lewy bodies (DLB) than Alzheimer's disease (AD). We examined differences in outcomes between patients with DLB and AD hospitalized for the treatment of behavioral and psychological symptoms of dementia. A chart review was conducted of patients with either AD or DLB hospitalized in the acute psychogeriatric ward between January 2008 and December 2011 in Kahoku-City, Ishikawa, Japan. Outcome measures were discharge destinations and time to death. A diagnosis of AD was made according to DSM-5 criteria, whereas a diagnosis of DLB was made according to the Consortium on DLB International Workshop criteria for probable DLB. Pharmacologic treatment was optimized under constant monitoring of patients. Cholinesterase inhibitors and yi-gan san were tried prior to antipsychotics in DLB patients. The study cohort consisted of 224 patients with AD and 106 with DLB. After matching for sociodemographic factors and cognitive and physical function, it was found that antipsychotics were less frequently used during hospitalization in patients with DLB than AD (63% vs 82%, respectively, P < .01), whereas cholinesterase inhibitors (88% vs 43%, P < .001) and yi-gan san (35% vs 20%, P < .05) were more frequently used in patients with DLB. There were no significant differences in discharge destinations between the 2 groups. The 5-year cumulative survival rates were similar in the AD and DLB groups (46.4% vs 45.7%, respectively, P = .6225). Optimization of pharmacologic treatment during hospitalization could reduce the use of antipsychotics and improve the subsequent clinical course in DLB.

YGS40, an active fraction of Yi-Gan San, reduces hydrogen peroxide-induced apoptosis in PC12 cells

In our previous study, we have elucidated the chemical profile of YGS40, a fraction of Yi-Gan San (YGS), used for the treatment of Alzheimer's disease (AD). Oxidative stress-induced apoptosis is implicated in neurodegenerative disorders such as AD. The aim of the present study was to explore the protective effects of YGS40 against hydrogen peroxide (H2O2)-induced apoptosis in PC12 cells and the underlying mechanisms. PC12 cells were exposed to 100 μmol·L−1 of H2O2 for 12 h with or without YGS40 pretreatment. Cytotoxicity was determined by MTT (3, (4, 5-dimethylthiazole-2-yl) 2, 5-diphenyl-tetrazolium bromide) and lactate dehydrogenase (LDH) release assays; apoptosis was detected by Annexin V/propidium iodide coupled staining and by determining caspase-3 activity and Bax and Bcl-2 protein levels. Mitochondrial membrane potential (MMP) was assessed by the retention of rhodamine123; and the activities of superoxide dismutase (SOD) and malondialdehyde (MDA) were measured using commercially available enzymatic kits. Pretreatment with YGS40 significantly prevented H2O2-induced cytotoxicity and protected the cells against H2O2-triggered apoptosis characterized by externalization of membrane phosphatidylserine and caspase-3 activation and the increased ratio of Bax/Bcl-2 in PC12 cells. Further studies showed that YGS40 suppressed H2O2-induced MMP loss, increased SOD activity, and decreased MDA level. These findings suggest that YGS40 may be beneficial for the prevention and treatment of oxidative stress-mediated disorders.

Chemical profile of the active fraction of Yi-Gan San by HPLC-DAD-Q-TOF-MS and its neuroprotective effect against glutamate-induced cytotoxicity

Yi-Gan San (YGS), a traditional Chinese medicine for dementia-related symptoms, was previously fractionated. One active fraction, YGS40 exhibited a neuroprotective effect against glutamate-induced cytotoxicity. In the present study, high-performance liquid chromatography, coupled with diode-array detection and quadrupole time-of-flight mass spectrometry, was applied for the identification of its chemical constituents and for quantification studies. The chemical profile of YGS40 consisted of sixty-four identified or tentatively characterized compounds. The levels of the major marker compounds increased significantly in the mixed decoction compared with those in the single plant decoction. The results suggest the high precision of the analyses of most of the constituents in YGS40 and establish the quantitative variations of the major marker compounds between the single and mixed decoction processes.

The metabolism of YiGan San and subsequent pharmacokinetic evaluation of four metabolites in rat based on liquid chromatography with tandem mass spectrometry.

A new method based on liquid chromatography-tandem time-of-flight mass spectrometry was developed to identify the metabolites in rat urine after oral administration of YiGan San (YGS). Eighteen prototype compounds and four metabolites named 11-hydroxyhirsuteine, 19-carbonylhirsutine, 19-carbonyl-dihydrocorynantheine, and 18-hydroxy-geissoschizine methyl ether were identified. Subsequently, a method of high-performance liquid chromatography coupled with triple-quadrupole mass spectrometry was established for pharmacokinetic study of YGS in rat plasma. The concentration-time curves of four prototype compounds, senkyunolide I, ajmalicine, isocorynoxeine and rhynchophylline were constructed after an oral (9.1g YGS per kilogram of body weight) administration in rats. Method validation revealed excellent linearity over the range 220.00-0.55, 220.00-0.55, 21.40-0.05, and 19.80-0.05ng/mL for the four prototype compounds respectively. The stabilities results indicate that all of the analytes were stable in rat plasma in the autosampler for 24h, under freeze/thaw cycles (4 times in 24h), and at -20°C for one week. Residual analysis, heteroskedasticity test, and goodness-of-fit test were also performed to determine the accuracy of the linear regression method. The pharmacokinetic parameters were obtained. Four hours after administration, compound 11-hydroxyhirsuteine can be detected in rat plasma. Compared with purified ligustilide, YGS required a slightly longer period to reach maximum concentration (Cmax) in rat plasma.

Yokukansan and its ingredients as possible treatment options for schizophrenia.

Schizophrenia is a debilitating psychotic mental disorder that affects almost the entire range of human mental function. The devastating effect of the illness is usually long-lasting and requires lifelong treatment. Despite an evolved psychopharmacological understanding, the overall therapeutic effect of antipsychotics is still not satisfactory. The choice of proper medication presents a clinical dilemma between efficacy and safety. As a result, searching for comparable treatment options with safer profiles is very important. Yokukansan (TJ-54), also called yi-gan san in Chinese, is a traditional herbal medicine with evident therapeutic effect for neuropsychiatric disorders. There are several open-label clinical studies upholding the possibility of using yokukansan to treat schizophrenia or schizophrenia-like psychosis. Evidence from animal studies and neurobiology also sheds light on the antipsychotic implications of yokukansan and its ingredients. Nevertheless, correlations between the experimental environment and clinical settings may be complicated by a number of confounders. Clinical trials with more sophisticated designs are required to fill the gap between the experimental environment and clinical settings.

Geissoschizine Methyl Ether, an Alkaloid from the Uncaria Hook, Improves Remyelination After Cuprizone-Induced Demyelination in Medial Prefrontal Cortex of Adult Mice

Accumulating evidence indicates that the medial prefrontal cortex (mPFC) is a site of myelin and oligodendrocyte abnormalities that contribute to psychotic symptoms of schizophrenia. The development of therapeutic approaches to enhance remyelination, a regenerative process in which new myelin sheaths are formed on demyelinated axons, may be an attractive remedial strategy. Geissoschizine methyl ether (GM) in the Uncaria hook, a galenical constituent of the traditional Japanese medicine yokukansan (Yi-gan san), is one of the active components responsible for the psychotropic effects of yokukansan, though little is known about the mechanisms underlying the effects of either that medicine or GM itself. In the present study, we employed a cuprizone (CPZ)-induced demyelination model and examined the cellular changes in response to GM administration during the remyelination phase in the mPFC of adult mice. Using the mitotic marker 5-bromo-2'-deoxyuridine (BrdU), we demonstrated that CPZ treatment significantly increased the number of BrdU-positive NG2 cells, as well as microglia and mature oligodendrocytes in the mPFC. Newly formed oligodendrocytes were increased by GM administration after CPZ exposure. In addition, GM attenuated a decrease in myelin basic protein immunoreactivity caused by CPZ administration. Taken together, our findings suggest that GM administration ameliorated the myelin deficit by mature oligodendrocyte formation and remyelination in the mPFC of CPZ-fed mice. The present findings provide experimental evidence supporting the role for GM and its possible use as a remedy for schizophrenia symptoms by promoting the differentiation of progenitor cells to and myelination by oligodendrocytes.

Analysis of the traditional medicine YiGan San by the fragmentation patterns of cadambine indole alkaloids using HPLC coupled with high‐resolution MS

YiGan San (YGS) has long been used in traditional Japanese and Chinese folk medicine and serves as a potent and novel therapeutic agent to treat Alzheimer's disease. In the present study, a rapid and sensitive method based on HPLC coupled with diode-array detection and quadrupole TOF MS (Q-TOF-MS) was designed to reveal the chemical constituents of YGS. Thirty-six compounds were identified and assigned in YGS, including 14 alkaloids, nine γ-lactones, six flavonoids, three triterpenoid saponinares, two small molecular organic acids, and two other types of compounds. In addition, the accurate fragment weight and MS/MS fragmentation reactions of a subtype indole alkaloid in Uncariae ramulus cum uncis were summarized for the first time to realize rapid identification without reference substances. For the first time, 11 major constituents were comprehensively quantified with a HPLC coupled with triple-quadrupole MS method. A three-section switch was used to realize such multicomponent identification. The contents of saikosaponin B2 and isoliquiritin, which produce anti-inflammatory and antidepressant-like effects, were extremely different, up to 700 times, in two sources of YGS. The developed qualitative and quantitative method was proved to be precise, accurate, and reproducible.

Evidence-based guideline: Treatment of tardive syndromes

To make evidence-based recommendations regarding management of tardive syndromes (TDS), including tardive dyskinesias (TDD), by addressing 5 questions: 1) Is withdrawal of dopamine receptor blocking agents (DRBAs) an effective TDS treatment? 2) Does switching from typical to atypical DRBAs reduce TDS symptoms? 3) What is the efficacy of pharmacologic agents in treating TDS? 4) Do patients with TDS benefit from chemodenervation with botulinum toxin? 5) Do patients with TDS benefit from surgical therapy? PsycINFO, Ovid MEDLINE, EMBASE, Web of Science, and Cochrane were searched (1966-2011). Articles were classified according to a 4-tiered evidence-rating scheme; recommendations were tied to the evidence. Clonazepam probably improves TDD and ginkgo biloba probably improves TDS (both Level B); both should be considered as treatment. Risperidone may improve TDS but cannot be recommended as treatment because neuroleptics may cause TDS despite masking symptoms. Amantadine and tetrabenazine might be considered as TDS treatment (Level C). Diltiazem should not be considered as TDD treatment (Level B); galantamine and eicosapentaenoic acid may not be considered as treatment (Level C). Data are insufficient to support or refute use of acetazolamide, bromocriptine, thiamine, baclofen, vitamin E, vitamin B6, selegiline, clozapine, olanzapine, melatonin, nifedipine, fluperlapine, sulpiride, flupenthixol, thiopropazate, haloperidol, levetiracetam, quetiapine, ziprasidone, sertindole, aripiprazole, buspirone, yi-gan san, biperiden discontinuation, botulinum toxin type A, electroconvulsive therapy, α-methyldopa, reserpine, and pallidal deep brain stimulation as TDS treatments (Level U). Data are insufficient to support or refute TDS treatment by withdrawing causative agents or switching from typical to atypical DRBA (Level U).

クモ膜下出血の術後せん妄にラメルテオンと抑肝散の併用が奏効したと考えられた1例

A 68-year-old woman presented with a sudden severe headache, vomiting, and disturbed consciousness. She was admitted to the emergency room. Computed tomography (CT) revealed a hemorrhage in the right temporal lobe. Angiography demonstrated a ruptured aneurysm in the right middle cerebral artery (MCA) and an unruptured aneurysm in the left MCA. The subarachnoid hemorrhage was grade 3 (Hunt and Kosnik classification). Emergency craniotomy, clipping of the ruptured aneurysm and removal of the hematoma were performed. The left hemiparesis improved, and the patient was able to walk. We prescribed triazolam (0.25 mg/day) to treat the patient's insomnia. The unruptured aneurysm was additionally clipped on the 15th hospital day. After the second operation, the patient complained of delirium with restlessness, excitement, disorganized behavior, and sleep disturbance. Treatment with thiapride (150 mg/day) did not improve the delirium. We additionally administered Yi-gan san (7.5 g/day) and switched the triazolam to ramelteon (8 mg/day). The Memorial Delirium Assessment Scale score improved dramatically (from 16 at onset to 5 on day 7 and 1 at two months). Yi-gan san is reported to be effective for the treatment of behavioral and psychological symptoms of dementia. Ramelteon, a melatonin receptor agonist, is implicated in the regulation of the sleep-wake cycle. Ramelteon, unlike other hypnotic drugs, does not cause oversedation, rebound insomnia, withdrawal symptoms or dependence. In addition, we have noted no adverse effects, including oversedation or clinically significant changes in laboratory data, during combination therapy. A combination of ramelteon and Yi-gan san may therefore be beneficial in elderly patients with delirium, especially when there is a risk of oversedation.

Yi-Gan San for Treatment of Charles Bonnet Syndrome (Visual Hallucination Due to Vision Loss)

Recent studies indicate that the traditional Japanese herbal medicine yi-gan san (YGS, yokukan-san in Japanese) may be safe and useful for treating behavioral and psychological symptoms in dementia, borderline personality disorder, neuroleptic-induced tardive dyskinesia, and treatment-resistant schizophrenia. Visual hallucinations are common and often distressing consequences of vision loss, particularly in age-related macular degeneration. Charles Bonnet syndrome (CBS) is defined by the triad of complex visual hallucinations, ocular pathology causing visual deterioration, and preserved cognitive status. We aimed at evaluating both the efficacy and safety of YGS in patients with CBS. Twenty patients diagnosed with CBS were investigated, according to the diagnostic criteria established by Gold and Rabins and Teunisse. Participants were treated in a 4-week open-label study with YGS at an average daily dose of 5.8 ± 2.6 g (2.5-7.5 g). Psychometric instruments used to assess efficacy included the Neuropsychiatric Inventory, hallucination subscale of the Positive and Negative Syndrome Scale, and Clinical Global Impression. No cases of serious adverse events were attributed to the study's drug therapy. A significant decrease in visual hallucination was observed at 2 and 4 weeks in the Neuropsychiatric Inventory, hallucination subscale of the Positive and Negative Syndrome Scale, and Clinical Global Impression scores. Yi-gan san may be an effective and safe therapy to control visual hallucination in patients with CBS and should be further tested in double-blind, placebo-controlled trials. Given the design characteristics of this trial, the present findings should be taken cautiously.

Use of Yi-Gan San (TJ-54) in patients with motor aphasia who refuse to participate in rehabilitation

Sato S, Bunno K. Use of Yi-Gan San (TJ-54) in patients with motor aphasia who refuse to participate in rehabilitation. Jpn J Compr Rehabil Sci 2010; 7-10. Since aphasic patients have difficulty communicating, they often have emotional lability, which can make clinical management difficult and may even lead to the patients' refusal to participate in rehabilitation programs. Yi-Gan San (YGS) has recently been shown to improve behavioral and psychological symptoms of dementia (BPSD) associated with Alzheimer's dementia. Recently, 3 patients with motor aphasia were treated with YGS to stabilize psychiatric symptoms, and this treatment helped the patients, who initially refused to undergo rehabilitation, adapt to rehabilitation therapy. Within 1 to 2 weeks of starting the treatment with YGS, there was a marked improvement in the patients' emotional lability. Since the patients showed improvement within a short period, we think that the serotonin 5-HT1A receptor partial agonist action of YGS is the main factor responsible for these pharmacologic effects. In patients with impaired communication ability, such as those with motor aphasia, YGS may be effective and worthwhile as a supplemental therapy for secondary psychiatric symptoms such as emotional lability.

Pharmacotherapy for visual hallucinations:

Charles Bonnet syndrome (CBS) consists of vivid visual hallucinations which occur in otherwise psychologically normal people with insight. We reviewed the literature associated with pharmacotherapy for CBS. According to the limited data, antipsychotics such as risperidone, mood stabilizers such as valproate, antidepressants such as mirtazapine and Chinese medicine such as Yi-gan san are candidate treatments for visual hallucinations. Since existing data is solely derived from case reports, further controlled studies are required to establish pharmacotherapy for CBS.

Involvement of the benzodiazepine system in the anxiolytic-like effect of Yokukansan (Yi-gan san)

The traditional Japanese Kampo medicine Yokukansan (YKS, Yi-gan san in Chinese) has been demonstrated to improve the behavioral and psychological symptoms of dementia (BPSD), such as anxiety, hallucinations, agitation and irritability. The aim of this study was to elucidate the mechanism of the anxiolytic-like effects of YKS and Chotoko, which is an active component of YKS. Oral treatment with YKS (300 and 1000 mg/kg) significantly increased the number of head-dipping behaviors in mice in the hole-board test. Head-dipping behavior in mice was also significantly increased by treatment with Chotoko (50 and 100 mg/kg, p.o.). In addition, oral treatment with the water-extracted fractions from YKS (YKS-W; 250 and 500 mg/kg, p.o.) and Chotoko (Chotoko-W; 10 and 30 mg/kg) significantly increased the number of head-dipping behaviors in mice. On the other hand, treatment with the methanol-extracted fraction of YKS (YKS-Met; 15 and 30 mg/kg, p.o.) did not affect head-dipping behavior. The total distance and number of rearing behaviors were not affected by treatment with any of these drugs. The increase in the number of head-dipping behaviors by treatment with YKS-W (500 mg/kg, p.o.) and Chotoko-W (30 mg/kg, p.o.) was inhibited by pretreatment with the benzodiazepine receptor antagonist flumazenil (1 mg/kg, i.v.). In the elevated plus-maze test, the percentage of time spent in open arms was increased in YKS (1000 mg, p.o.) treatment. Based on these results, we suggest that YKS produces an anxiolytic-like effect mediated by the benzodiazepine system. Chotoko is an effective component of YKS for producing an anxiolytic-like effect. The effective compound(s) should be contained, at least in part, in the water-soluble fraction of YKS.

Comparative efficacy of risperidone versus yi-gan san on behavioural and psychological symptoms of dementia

Comparative efficacy of risperidone versus yi-gan san on behavioural and psychological symptoms of dementia

Traditional Chinese medicine on four patients with Huntington's disease

Four Huntington's disease (HD) patients were treated with traditional Chinese medicines Yi-Gan San (YGS) and Chaihu-Jia-Longgu-Muli Tan (CLMT) in a cross-over manner. Two patients took YGS for 8 weeks first, and after 4 weeks of washing out, they took CLMT for 8 weeks. Two other patients took these medicines in reverse order. All patients showed a decrease in the Unified Huntington's Disease Rating Scale-motor assessment (from 106.3 +/- 4.7 to 89.6 +/- 5.8 as mean +/- SD, P = 0.0004) by YGS treatment with no extrapiramidal symptoms or changes of cognition or ADL. Our study suggests a possibility of a new treatment for involuntary movements.

Yi-Gan San Restores Behavioral Alterations and a Decrease of Brain Glutathione Level in a Mouse Model of Schizophrenia

The traditional Chinese herbal medicine yi-gan san has been used to cure neuropsychological disorders. Schizophrenia can be one of the target diseases of yi-gan san. We aimed at evaluating the possible use of yi-gan san in improving the schizophrenic symptoms of an animal model. Yi-gan san or distilled water was administered to mice born from pregnant mice injected with polyinosinic-polycytidilic acid or phosphate buffered saline. The former is a model of schizophrenia based on the epidemiological data that maternal infection leads to psychotic disorders including schizophrenia in the offspring. Prepulse inhibition and sensitivity to methamphetamine in open field tests were analyzed and the total glutathione content of whole brains was measured. Yi-gan san reversed the decrease in prepulse inhibition, hypersensitivity to methamphetamine and cognitive deficits found in the model mice to the level of control mice. Total glutathione content in whole brains was reduced in the model mice but was restored to normal levels by yi-gan san treatment. These results suggest that yi-gan san may have ameliorating effects on the pathological symptoms of schizophrenia.

Chinese Herbal Medicine Yi-Gan-San Decreases the Lipid Accumulation in Mouse 3T3-L1 Adipocytes by Modulating the Activities of Transcription Factors SREBP-1c and FoxO1

Abnormal lipid metabolism in adipose tissue is closely related to the occurrence and progression of a wide variety of metabolic syndromes. We have analyzed the pharmacological effects of Chinese herbal medicines on cell differentiation and lipid metabolism in adipocytes. Yi-Gan-San (YGS) is a Chinese herbal medicine that is effective in treating the behavioral and psychological symptoms of dementia; however, its physiological mechanism remains unclear. We analyzed the effects of YGS on lipid accumulation in mouse 3T3-L1 adipocytes. Adipocyte differentiation was induced in mouse 3T3-L1 preadipocytes by treatment with the mixture of dexamethasone, 3-iso-butyl-1-methylxanthine, and insulin, and cells were cultured for 8 days with Chinese herbal medicines, including YGS. YGS effectively reduced the lipid accumulation in the differentiated 3T3-L1 cells in a dose-dependent manner, but had no effect on cell viability. YGS also reduced the activity of glycerol-3-phosphate dehydrogenase, an enzyme involved in lipid synthesis. In contrast, YGS gave no noticeable effect on glucose uptake and fatty acid uptake in the differentiated 3T3-L1 cells. Moreover, we established the stably transfected 3T3-L1 cell lines, each of which expresses the luciferase reporter gene under the control of sterol regulatory element-binding protein-1c (SREBP-1c) or FoxO1. SREBP-1c is a transcription factor involved in fatty acid synthesis, and FoxO1 is a forkhead-type transcription factor involved in adipocyte differentiation. Using these cell lines, we showed that YGS reduced the transcriptional activity of SREBP-1c, whereas YGS increased the activity of FoxO1. Thus, YGS may suppress lipid synthesis and fat accumulation in adipocytes through modulating the activities of SREBP-1c and FoxO1.