Antidepressant-like effects of the saponins extracted from Chaihu-jia-longgu-muli-tang in a rat unpredictable chronic mild stress model

Antidepressant effect of PT-31, an α₂-adrenoceptor agonist, on lipopolysaccharide-induced depressive-like behavior in mice

Increasing evidence indicates that neuroinflammation, oxidative stress, and neurotrophic factors play a key role in the pathophysiology of major depressive disorder (MDD). In addition, the attenuation of inflammatory response has been considered a putative mechanism for MDD treatment. PT-31 is an imidazolidine derivative and a putative α₂-adrenoceptor agonist that has previously demonstrated antinociceptive activity. The present study aimed to investigate the effect of PT-31 on depressive-like behavior and lipopolysaccharide-induced neurochemical changes. To this end, mice received intraperitoneally saline or lipopolysaccharide (600 µg/kg), and 5 h postinjection animals were orally treated with saline, PT-31 (3, 10, and 30 mg/kg), or fluoxetine (30 mg/kg). Mice were subjected to the open field test (OFT) 6 and 24 h after lipopolysaccharide administration and to the tail suspension test (TST) 24 h postlipopolysaccharide. Subsequently, animals were euthanized, and brains were dissected for neurochemical analyses. The administration of lipopolysaccharide-induced sickness- and depressive-like behaviors, besides promoting an increase in myeloperoxidase activity and a reduction in brain-derived neurotrophic factor (BDNF) levels. Noteworthy, PT-31 3 mg/kg attenuated lipopolysaccharide-induced decreased locomotor activity 6 h after lipopolysaccharide in the OFT. All tested doses of PT-31 significantly reduced the immobility time of animals in the TST and attenuated lipopolysaccharide-induced increased myeloperoxidase activity in the cortex of mice. Our results demonstrate that PT-31 ameliorates behavioral changes promoted by lipopolysaccharide in OFT and TST, which is possibly mediated by attenuation of the inflammatory response.

Efficacy and Safety of Chaihu Jia Longgu Muli Decoction in the Treatment of Poststroke Depression: A Systematic Review and Meta-Analysis

Objective

Chaihu Jia Longgu Muli decoction (CLMD) is widely used in the treatment of poststroke depression (PSD) in China. Some evidences show that it has advantages, but there lacks reliable evidence. This study aims to systematically evaluate the efficacy and safety of CLMD in the treatment of PSD.

Methods

All randomized controlled trials (RCTs) of CLMD in the treatment of PSD were searched from the following databases: PubMed, Cochrane Library, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP Database, and Chinese Biomedical Literature Service System (CBM), from their inception to May 2021. Two researchers independently screened the literature, extracted the data, and evaluated the risk of bias in the included studies. Meta-analysis was performed using RevMan5.3 software.

Results

A total of 13 RCTs involving 1665 patients were finally included in this study, among which 5 RCTs were oral CLMD alone versus antidepressants, and 8 RCTs were oral CLMD with antidepressants versus antidepressants. Meta-analysis results showed that oral administration of CLMD could improve Hamilton's Depression Scale (HAMD) and the Modified Edinburgh-Scandinavian Stroke Scale (MESSS) scores, improve the Barthel index, and have a low rate of adverse reactions, but there was no significant difference in the total effective rate (p=0.21 > 0.05) and the National Institute of Health Stroke Scale (NIHSS) score (p=0.47 > 0.05) between the antidepressants group and the oral administration of the CLMD group. Oral CLMD combined with antidepressants could improve the total effective rate, HAMD, and MESSS score, but there was no significant difference in Barthel index (p=0.06 > 0.05) and the adverse reaction rate (p=0.14 > 0.05) between the two groups.

Conclusion

Current evidence suggests that oral CLMD alone or with antidepressants is more effective and safer in the treatment of PSD than oral antidepressants. Due to the limitation of the quality and quantity of the included studies, more high-quality studies are needed to confirm the above conclusion.

Chaihu-Longgu-Muli Decoction exerts an antiepileptic effect in rats by improving pyroptosis in hippocampal neurons

ETHNOPHARMACOLOGICAL RELEVANCE

Chaihu-Longgu-Muli Decoction (CLMD) is a classic prescription created by Zhong-jing Zhang, a famous ancient Chinese medical scientist, to harmonize uncontrollable body activities and calm the minds. Now Traditional Chinese Medicine (TCM) physicians often apply it to treat psychiatric diseases such as epilepsy.

AIM OF THE STUDY

This study investigated the mechanism of the effect of Chaihu-Longgu-Muli Decoction (CLMD) on hippocampal neurons pyroptosis in rats with Temporal Lobe Epilepsy (TLE).

MATERIALS AND METHODS

The lithium chloride-pilocarpine-induced TLE rat model was established. The behavioral testing was performed and, the expression of IL-1β and TNF-α in serum was detected by ELISA, qRT-PCR was used to detect the mRNA expression of NLRP3, Caspase-1, IL-1β and TNF-α in hippocampus. The expression of NLRP3 and Caspase-1 in hippocampal dentate gyrus was detected by immunofluorescence assay.

RESULTS

CLMD could significantly suppress the frequency and duration time of epileptic seizures, reduce the expression of NLRP3, Caspase-1 TNF-α and IL-1β.

CONCLUSIONS

CLMD exerted an obvious antiepileptic effect by improving pyroptosis in hippocampal neurons of TLE rats.

Chaihu plus Longgu Muli Decoction Alleviated Brain Injury in Pentylenetetrazole-Kindled Epileptic Mice by Regulating Cyclooxygenase-2/Prostaglandin E2/Multidrug Transporter Pathway

Objective. To evaluate the effect of CLMD administration on epileptic seizures and brain injury in pentylenetetrazole- (PZT-) kindled mice. Methods. The effect of pretreatment with CLMD (5, 10, and 20 ml/kg (mg/kg) by gavage) for seven days on PTZ-induced kindling, duration and grade of kindling-induced seizures, and pathological injury in the cortex and hippocampus was evaluated. Male BALB/c mice with adenosine A1 receptor knockout were subjected to intraperitoneal injection of PTZ (35 mg/kg) once every day until kindling was successfully induced. Quantitative reverse transcription polymerase chain reaction, immunofluorescence, and western blot were performed to assess the mRNA and protein levels of p-glycoprotein (PGP), multidrug resistance-associated protein 1 (MRP1), cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), and adenylate kinase (ADK) in the cortex and hippocampus. Results. PTZ successfully induced kindling in mice after 21 days, wherein CLMD showed an obvious dose-dependent antiepileptic effect. High-dose CLMD significantly increased the latency of epileptic seizures, decreased the sustained time of epileptic seizures and the seizure grade, and ameliorated the histopathological changes in the cortex and hippocampus. Furthermore, PTZ kindling induced significantly higher levels of PGP, MRP1, COX-2, PGE2, and ADK, but this effect was inhibited by pretreatment with CLMD in a dose-dependent manner. Conclusion. Pretreatment with CLMD attenuates PTZ-kindled convulsions and brain injury in mice. The mechanism may be related to the cyclooxygenase-2/prostaglandin E2/multidrug transporter pathway.

Chinese Herbal Products for Non-Motor Symptoms of Parkinson's Disease in Taiwan: A Population-Based Study

Objective: Combinations of Chinese herbal products (CHPs) are widely used for Parkinson’s disease (PD) in Taiwan. Thereby, we investigated the use of CHPs in patients with PD.

Methods: This study was a population-based cohort study that analyzed the data of patients with PD from the National Health Insurance Research Database. A total of 9,117 patients were selected from a random sample of one million individuals included in this database. We used multiple logistic regression models to estimate the adjusted odds ratios of the demographic factors and analyzed the formula and single CHPs commonly used for PD.

Results: Traditional Chinese medicine users were more commonly female, younger, of white-collar status, and residents of Central Taiwan. Chaihu-Jia-Longgu-Muli-Tang was the most commonly used formula, followed by Ma-Zi-Ren-Wan and then Shao-Yao-Gan-Cao-Tang. The most commonly used single herb was Uncaria tomentosa (Willd. ex Schult.) DC., followed by Gastrodia elata Blume and then Radix et Rhizoma Rhei (Rheum palmatum L., Rheum tanguticum Maxim. ex Balf., and Rheum officinale Baill.). Chaihu-Jia-Longgu-Muli-Tang and U. tomentosa (Willd. ex Schult.) DC. have shown neuroprotective effects in previous studies, and they have been used for managing non-motor symptoms of PD.

Conclusion: Chaihu-Jia-Longgu-Muli-Tang and U. tomentosa (Willd. ex Schult.) DC. are the most commonly used CHPs for PD in Taiwan. Our results revealed the preferences in medication prescriptions for PD. Further studies are warranted to determine the effectiveness of these CHPs for ameliorating the various symptoms of PD, their adverse effects, and the mechanisms underlying their associated neuroprotective effects.

The cardioprotective and anxiolytic effects of Chaihujialonggumuli granule on rats with anxiety after acute myocardial infarction is partly mediated by suppression of CXCR4/NF-κB/GSDMD pathway

AIMS

Over-expression of CXCR4 activates nuclear translocation of NF-κB, induces high expression of NLRP3, GSDMD, IL-1β and IL-18, which promotes severe inflammatory response following myocardial infarction. Previous studies revealed inflammation induces anxiety after myocardial infarction. The Chaihujialonggumuli granule has anti-inflammatory properties and could tranquillize mind. But the mechanism of its efficacy remains unknown. This study was to investigate the possible mechanism of BFG on cardioprotective and anxiolytic.

METHODS

The expression of CXCR4, NF-κB, NLRP3and GSDMD was measured with western-blot, QRT-PCR. The expression location of CXCR4, NLRP3, GSDMD were determined by immunohistochemistry. IL-1β、IL-18 in the peripheral blood were measured by ELISA. HE staining, Masson staining and transmission electron microscopy were used to observe morphological changes of cardiomyocytes. Echocardiography was used to assess cardiac function after cardiac surgery. Elevated cross maze test and open field test were used to evaluate behaviours. Western blot was used to detect the protein expressions of 5-HT, DA, IL-1β, IL-18 and neuron damage was investigated by Nissl staining in the hippocampus.

RESULTS

The up-regulation of CXCR4, NF-κB, NLRP3 and GSDMD were found in the infarcted area after left coronary artery ligation. Pathological staining and analysis showed that more severe inflammatory cytokines infiltration, myocardial fibrosis, were found in myocardial tissue of the complex group rats. And when compared to the sham group, the levels of IL-1β, IL-18 was increased of the complex group in both peripheral blood and brain. Behavioural test and echocardiography indicated that the rats in complex group exploration behaviours was significantly reduced, and with poor cardiac functional recovery. The AMD3100 had an inhibitory impact of CXCR4 on the activition of its downstream effectors, alleviating inflammatory reaction. Furthermore, the BFG decreased the expression level of CXCR4, NF-κB, GSDMD, NLRP3 in the infarcted area after myocardial infarction, when compared to the complex group. The assays in the brain indicated the BFG suppressed expression and activity of IL-1β, IL-18, and improved 5-HT and DA synthesis.

CONCLUSIONS

In sum, our study indicated that BFG may reduce inflammation, treat co-existing anxiety after myocardial infarction through inhibition of CXCR4/NF-κB/GSDMD signalling.

Anti-depressant effect of cerebrolysin in reserpine-induced depression in rats: Behavioral, biochemical, molecular and immunohistochemical evidence

Depression is a major psychological disorder that contributes to global health problem. This study aimed to evaluate the anti-depressant effect of Cerebrolysin (CBL) in Reserpine-induced depressed rats, its effect on oxidative stress, inflammation, regulatory cyclic AMP-dependent response element binding protein (CREB)/brain derived neurotropic factor (BDNF) signaling pathways, brain monoamines and histopathological changes was assessed. Rats received either the vehicle or Reserpine (0.5 mg/kg, i.p.) for 14 days. The other three groups were pretreated with CBL (2.5, 5 ml/kg; i.p.) or fluoxetine (FLU) (5 mg/kg, p.o.), respectively for 14 days, 30 min before reserpine injection. Then analyses were conducted. CBL reversed Reserpine-induced reduction in latency to immobility and prolongation of immobility time in the forced swimming test (FST), reduced malondialdehyde (MDA), elevated reduced glutathione (GSH), reduced tumor necrosis factor-alpha (TNF-ɑ), and elevated BDNF cortical and hippocampal brain contents. CBL elevated protein kinase A (PKA) and nuclear factor kappa-B (NF-κB) cortical and hippocampal protein expressions. CBL also ameliorated alterations in mRNA expressions of protein kinase B (AKT), CREB and BDNF in the cortical and hippocampal tissues. CBL elevated nor-epinephrine (NE), serotonin (5-HT), and dopamine (DA) and reduced 5-Hydroxyindoleacetic acid (5-HTAA), 3,4-Dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) cortical and hippocampal contents. CBL effects were in parallel to those observed with the standard anti-depressant drug, FLU. This study shows that CBL exerted anti-depressant effect evidenced by attenuation of oxidative stress and inflammation as well as enhancement of neurogenesis, amelioration of monoaminergic system and histopathological changes.

Traditional Chinese Medicine in Depression Treatment: From Molecules to Systems

Depression is a multigenetic or multifactorial syndrome. The central neuron system (CNS)-orientated, single target, and conventional antidepressants are insufficient and far from ideal. Traditional Chinese Medicine (TCM) has historically been used to treat depression up till today, particularly in Asia. Its holistic, multidrug, multitarget nature fits well with the therapeutic idea of systems medicine in depression treatment. Over the past two decades, although efforts have been made to understand TCM herbal antidepressants at the molecular level, many fundamental questions regarding their mechanisms of action remain to be addressed at the systems level in order to better understand the complicated herbal formulations in depression treatment. In this Mini Review, we review and discuss the mechanisms of action of herbal antidepressants and their acting targets in the pathological systems in the brain, such as monoamine neurotransmissions, hypothalamic–pituitary–adrenal (HPA) axis, neurotropic factor brain-derived neurotrophic factor (BDNF) cascade, and glutamate transmission. Some herbal molecules, constituents, and formulas are highlighted as examples to discuss their mechanisms of action and future directions for comprehensive researches at the systems level. Furthermore, we discuss pharmacological approaches to integrate the mechanism of action from the molecular level into the systems level for understanding of systems pharmacology of TCM formulations. Integration of the studies at the molecular level into the systems level not only represents a trend in TCM study but also promotes our understanding of the system-wide mechanism of action of herbal antidepressant formulations.

Antidepressant-like effect of a standardized hydroethanolic extract of Asparagus adscendens in mice

OBJECTIVE:

Asparagus adscendens Roxb. (Liliaceae), a traditional herbal medicine, has been used as an aphrodisiac and brain tonic in Asian countries. The aim of the present study is to investigate the antidepressant-like effect of standardized hydroethanolic extract of A. adscendens root and its possible mechanisms.

MATERIALS AND METHODS:

Mice administered with vehicle, imipramine (15 mg/kg/day; i.p.), and A. adscendens extract (AAE) (25, 50, and 100 mg/kg/day; i.p.) for 14 days were subjected to behavioral tests including forced swimming test (FST), tail suspension test (TST), and open-field test (OFT) on the 14^th day. In order to explore the underlying mechanism behind an antidepressant effect of AAE, the brain monoamine levels, oxidative stress parameters, and serum corticosterone levels were monitored.

RESULTS:

Our results indicated that pretreatment of AAE (25, 50, and 100 mg/kg) for 14 days statistically significantly (P < 0.01) demonstrated antidepressant-like effect as evidenced by reduced immobility time in both FST (105, 78.6, and 53.6 s) and TST (97.6, 73.5, and 54.67 s), with no significant change in spontaneous locomotor activities as observed in OFT. Further, the behavioral improvement was supported by the statistically significantly (P < 0.05) enhanced levels of monoamines and reduced corticosterone level along with amelioration of oxidative stress in AAE-treated animals as compared to vehicle control group.

Conclusion:

Our findings clearly demonstrated the antidepressant-like effect of AAE, which might have been mediated through the modulation of monoaminergic system and by regulating hypothalamic–pituitary–adrenal axis with amelioration of oxidative stress.

Baicalin ameliorates chronic mild stress-induced depression-like behaviors in mice and attenuates inflammatory cytokines and oxidative stress

The natural flavonoid glycoside baicalin (BA) produces a variety of pharmaceutical effects, particularly for psychiatric/neurological disorders. This study evaluated the behavioral and neuroprotective effects of BA in mice subjected to chronic unpredictable mild stress, a model of depression. BA (25 and 50 mg/kg) significantly increased sucrose consumption and reduced immobility times in the tail suspension and forced swim tests, demonstrating that BA alleviated depression-like behaviors. Moreover, BA reduced the levels of inflammatory cytokines, such as interleukin 1β, interleukin 6, and tumor necrosis factor α, in serum and in the hippocampus. BA also abrogated increases in NMDAR/NR2B and Ca²⁺/calmodulin-dependent protein kinase II, and the decrease in phosphorylated ERK and reactive oxygen species production in mice subjected to chronic unpredictable mild stress. These findings suggested that the antidepressive effects of BA are due to the regulation of an NMDAR/NR2B-ERK1/2-related pathway and inhibition of inflammatory cytokines and oxidative stress. Thus, BA represents a potential candidate drug for patients suffering from depression.

Immediate and persistent antidepressant-like effects of Chaihu-jia-Longgu-Muli-tang are associated with instantly up-regulated BDNF in the hippocampus of mice

Conventional antidepressants have a disadvantage in delayed onset of efficacy. Here, we aimed to evaluate the immediate and persistent antidepressant-like action of a classic herbal medicine Chaihu-jia-Longgu-Muli decoction (CLM) as well as the action of CLM on hippocampal brain-derived neurotrophic factor (BDNF) over time. CLM consists of Xiaochaihu decoction (XchD), Longgu-Muli (LM) and several other herbs. The contribution of constituent herbal formula XchD and other parts of CLM was also assessed. Following a single dose of CLM, tail suspension test (TST), forced swim test (FST), and novelty-suppressed feeding test (NSF) were performed. The antidepressant activity of XchD, its interaction with LM or remaining parts of CLM was also examined after a single administration. BDNF expression in the hippocampus was examined at 30 min and 24 hr post a single CLM. A single administration of half of clinical dose of CLM elicited antidepressant effects at TST 30 min post administration, and lasted for 72 hr. Furthermore, CLM also reduced the latency to eat in NSF test. A single proportional dose of XchD induced antidepressant effects at 30 min and lasted for 48 hr, whereas the effect lasted for 72 hr when combined with either LM or the remaining parts of CLM. BDNF expression increased at 30 min and persisted at least for 24 hr after a single dose of CLM. The results support that Chaihu-jia-Longgu-Muli decoction was capable to immediately and enduringly elicit antidepressant activity via enhancement of hippocampal BDNF expression, in which the constituent Xiaochaihu decoction played the primary role.

Helicid Ameliorates Learning and Cognitive Ability and Activities cAMP/PKA/CREB Signaling in Chronic Unpredictable Mild Stress Rats

Helicid (4-formylphenyl-O-β-D-allopyranoside), an active component found in seeds from the Chinese herb Helicia nilagirica, has been reported to exert sedative, analgesic, hypnotic and antidepressant effects. The present study was designed to evaluate the antidepressant, learning and cognitive improvement effects of helicid in a chronic unpredictable mild stress (CUMS) model of depression in rats and to explore cAMP/protein kinase A (PKA)/cAMP response element-binding (CREB) signaling pathway. Sprague-Dawley rats were randomly assigned to six groups (n = 10): control; CUMS; CUMS + fluoxetine (5 mg/kg) and CUMS + helicid at 8, 16 and 32 mg/kg. All rats were subjected to 12 weeks of CUMS protocols and drug administration during the last 6 weeks of CUMS. Our results showed that helicid, at a dose of 32 mg/kg, significantly reversed decreases in body weight and sucrose consumption, increased the distance and number of crossings in the open-field test (OFT), reduced immobility times in the forced swimming test (FST) and improved spatial memory in the Morris water maze (MWM); all of these effects had been induced by CUMS paradigm. Immunohistochemistry showed that administration of helicid could promoted the proliferation of neurons in the hippocampal CA1 and dentate gyrus (DG) regions. CUMS rats treated with helicid had dramatically decreased protein levels of serotonin transporters (SERTs). In addition, CUMS resulted in a significant reduction in the expression of cAMP, PKA C-α and p-CREB, each of which were partially attenuated by helicid administration. These results indicated that helicid could improve depressive behaviors, learning and cognitive deficits and increase hippocampal neurogenesis, which may be mediated by the regulation of SERTs, activation of the cAMP/PKA/CREB signaling pathway and upregulation of p-CREB levels in hippocampal.

L-theanine ameliorate depressive-like behavior in a chronic unpredictable mild stress rat model via modulating the monoamine levels in limbic-cortical-striatal-pallidal-thalamic-circuit related brain regions

L-theanine, originally found in green tea, elicits various physiological effects, such as promoting relaxation, improving concentration and learning ability, and providing antianxiety-like and antidepressant-like properties. This study aims to investigate the effects of L-theanine (2 mg/kg) on monoamine levels in an animal model of depression. The effect of l-theanine on the symptoms of depression was examined through the open-field test, sucrose preference test, and forced swim test. The monoamine neurotransmitters that involve serotonin (5-HT), norepinephrine (NE), and dopamine (DA) were measured in the limbic-cortical-striatal-pallidal-thalamic (LCSPT)-circuit related brain regions, including the prefrontal cortex (PFC), nucleus accumbens (NAC), striatum (ST), amygdala, and hippocampus (HIP). L-theanine ameliorated the depressive-like behaviors in the chronic unpredictable mild stress (CUMS) rat model. In the PFC, NAC, and HIP, L-theanine administration significantly increased the levels of 5-HT, NE, and DA. In the ST, the levels of 5-HT and DA were increased after the administration of L-theanine. However, in the HIP, only the level of DA significantly changed after the treatment of L-theanine. Taken together, these results indicated that L-theanine has possibly antidepressant-like effects in the CUMS rat model, which could be mediated by the monoamine neurotransmitters in the LCSPT-circuit related brain regions.

Neuroplasticity-related mechanisms underlying the antidepressant-like effects of traditional herbal medicines

Traditional herbal medicine can offer efficacious and safe alternative pharmacotherapies for depression. The ability of an herbal medicine to produce neuroadaptive processes, that enhance neuroplasticity and cellular resilience in response to chronic stress, may point to its antidepressant potential. We suggest that among many investigated herbal medicines, those that can enhance neuroplasticity may have stronger therapeutic potential. The current article presents a summary of traditional herbal medicines, which are thought to exert antidepressant-like effects in chronic stress models via neuroplasticity enhancement. Brain-derived neurotrophic factor (BDNF) is a biomarker for neuroplasticity-related mechanisms compromised in depression and recovered by conventional antidepressants, including synaptic plasticity, cell survival, neurogenesis and spine formation. We therefore presumed that if an herbal medicine up-regulates BDNF in the hippocampus and/or prefrontal cortex (PFC), its antidepressant-like effect is mediated, at least partially, via neuroplasticity-related mechanisms. Literature search was performed using the general terms depression, stress, neuroplasticity and herbal medicines. Screening of retrieved preclinical studies revealed 30 traditional herbal medicines: 8 single herbs, 15 bioactive constituents, and 7 herbal formulas. The antidepressant-like effects of these medicines were associated with reversal of chronic stress-induced impairment in neuroplasticity, most notably by BDNF up-regulation, activation of BDNF downstream signaling pathways and increase in neurogenesis in the hippocampus and/or PFC/frontal cortex. In light of the ability of these medicines to enhance neuroplasticity, we suggest that they may be suitable candidates for clinical investigation in depressed individuals. Once their efficacy, tolerability and safety will be substantiated, they may serve as natural alternatives to conventional antidepressants.

Baicalin ameliorates chronic unpredictable mild stress-induced depressive behavior: Involving the inhibition of NLRP3 inflammasome activation in rat prefrontal cortex

Abnormal activation of nucleotide-binding domain, leucine-rich repeat, pyrin domain containing protein 3 (NLRP3) inflammasome could induce inflammation in the central nervous system and result in the hyperactivity of HPA axis, which were involved in the pathophysiology of depression. Baicalin, a major polyphenol compound extracts from Scutellaria radix roots, has been previously confirmed to normalize the hyperactivity of HPA axis in rats received chronic mild stress. However, its antidepressant effects and mechanisms are remains unclear in chronic unpredictable mild stress (CUMS) model of depression. In this study, CUMS treated rats showed a notable depressive-like behavior (decreased sucrose intake and locomotor activity, and increased immobility time), and significant increase in the activation of NLRP3 inflammasome and the levels of pro-inflammatory cytokines (IL-1β and IL-6) in rat prefrontal cortex. Treatment with baicalin (20, 40mg/kg) significantly reversed these changes. The present study confirmed that baicalin has antidepressant effect and its mechanisms likely related to the inhibition of NLRP3 inflammasome activation in rat prefrontal cortex.

Rhodioloside ameliorates depressive behavior via up-regulation of monoaminergic system activity and anti-inflammatory effect in olfactory bulbectomized rats

Rhodioloside, a major constituent from roots of Rhodiola rosea, has been previously confirmed to alleviate the hyperactivity in olfactory bulbectomized (OBX) rats exposed to the open field and to decrease the immobility time in the forced swimming test (FST) and tail suspension test (TST). However, its antidepressant effects and mechanisms remain unclear. This study aimed to evaluate the antidepressant effect and the potential mechanisms of rhodioloside in OBX rats. ELISA kits, HPLC-MS and western blot analysis were applied to explore the underlying antidepressant mechanisms of rhodioloside. Rhodioloside (20, 40mg/kg) significantly reversed OBX-induced reduction in sucrose consumption. It was also observed that administration of rhodioloside (20, 40mg/kg) decreased pro-inflammatory cytokines interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) levels and inhibits nuclear factor-kappa B (NF-κB) activation, as well as normalized the monoaminergic system changes in prefrontal cortex (PFC) of OBX rats. These results confirmed the antidepressant-like effect of rhodioloside, which might be primarily based on its up-regulation of the monoaminergic system activity and anti-inflammatory effect.

The effect of Piper laetispicum extract (EAE-P) during chronic unpredictable mild stress based on interrelationship of inflammatory cytokines, apoptosis cytokines and neurotrophin in the hippocampus

Backgroud

The Piper laetispicum C.DC. (Piperaceae) is a traditionally used herb in China for invigorating circulation and reducing stasis, detumescence and analgesia, which is distributed in the southern part of China and the southeastern part of Asia. Previous studies demonstrated that the ethyl acetate extract (EAE-P) of P. laetispicum possesses a significant antidepressant-like effect at doses higher than 60 mg/kg in Kunming (KM) mice, and this effect was not due to an increase in locomotive activity.

Methods

To research this mechanism, in the present study, the chronic unpredictable mild stress (CUMS) model in Sprague–Dawley rats was used to further elucidate behavioral changes and corresponding changes in inflammatory cytokines (TNF-α, IL-6, IL-10), apoptosis cytokines (P53, Bax, Bcl2, caspase-3) and neurotrophin (BDNF) in the hippocampus of EAE-P treatment animals.

Results and conclusions

The results suggest that EAE-P is beneficial to the behavioral outcome of the CUMS model animals, and decreased amounts of inflammatory cytokine IL-6 contributed to the antidepressant-like activation of EAE-P in every dosage group (15, 30, 60 mg/kg). In the low dosage group, down-regulated apoptosis cytokine p53 is associated with EAE-P effect, but it is inflammatory cytokine TNF-α that is related to the effect of EAE-P in the high dosage group. Meanwhile, the P53-dependent antiapoptotic effect of EAE-P may not be through Bcl-2 and Bax modulation. Furthermore, EAE-P showed up-regulated expression of brain-derived neurotrophic factor (BDNF) mRNA and down-regulated apoptosis cytokine caspase-3 mRNA, which was the same change tendency as with Fluoxetine.

In vivo study on the neurotransmitters and their metabolites change in depressive disorder rat plasma by ultra high performance liquid chromatography coupled to tandem mass spectrometry

A sensitive and versatile, ultra-high performance, liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method coupled to pre-column derivatization for the simultaneous determination of 5-hydroxytryptamine (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), dopamine (DA), norepinephrine (NE), homovanillic acid (HVA), γ-aminobutyric acid (GABA) and glutamic acid (Glu) was developed and validated in rat plasma. The analytes were dansylated under strong alkaline conditions after protein precipitation extraction, which were analyzed on a BEH C18 column using a gradient elution. The lower limit of quantification (LLOQ) values for 5-HT, 5-HIAA, DA, NE, HVA, GABA and Glu were 1.00, 1.00, 0.991, 0.992, 1.02, 1000, and 5030 pmol/mL, respectively. Good linearity was obtained (r > 0.99) and the intra- and inter-day precisions of the method (relative standard deviation, RSD%) were lower than 12%. The method was novel, sensitive and specific which can provide an alternative method for the quantification of neurotransmitters and their metabolites in plasma samples.

Emodin opposes chronic unpredictable mild stress induced depressive-like behavior in mice by upregulating the levels of hippocampal glucocorticoid receptor and brain-derived neurotrophic factor

Emodin, the major active component of Rhubarb, has shown neuroprotective activity. This study is attempted to investigate whether emodin possesses beneficial effects on chronic unpredictable mild stress (CUMS)-induced behavioral deficits (depression-like behaviors) and explore the possible mechanisms. ICR mice were subjected to chronic unpredictable mild stress for 42 consecutive days. Then, emodin and fluoxetine (positive control drug) were administered for 21 consecutive days at the last three weeks of CUMS procedure. The classical behavioral tests: open field test (OFT), sucrose preference test (SPT), tail suspension test (TST) and forced swimming test (FST) were applied to evaluate the antidepressant effects of emodin. Then plasma corticosterone concentration, hippocampal glucocorticoid receptor (GR) and brain-derived neurotrophic factor (BDNF) levels were tested to probe the mechanisms. Our results indicated that 6 weeks of CUMS exposure induced significant depression-like behavior, with high, plasma corticosterone concentration and low hippocampal GR and BDNF expression levels. Whereas, chronic emodin (20, 40 and 80 mg/kg) treatments reversed the behavioral deficiency induced by CUMS exposure. Treatment with emodin normalized the change of plasma corticosterone level, which demonstrated that emodin could partially restore CUMS-induced HPA axis impairments. Besides, hippocampal GR (mRNA and protein) and BDNF (mRNA) expressions were also up-regulated after emodin treatments. In conclusion, emodin remarkably improved depression-like behavior in CUMS mice and its antidepressant activity is mediated, at least in part, by the up-regulating GR and BDNF levels in hippocampus.

Effectiveness of saikokaryukotsuboreito (herbal medicine) for antipsychotic-induced sexual dysfunction in male patients with schizophrenia: a description of two cases

Antipsychotics sometimes cause sexual dysfunction in people with schizophrenia. The authors report the effectiveness of Saikokaryukotsuboreito (Japanese traditional herbal medicine, Chai-Hu-Jia-Long-Gu-Mu-Li-Tang in Chinese) for antipsychotic-induced sexual dysfunction in two male patients with schizophrenia. The first patient was a 28-year-old man with schizophrenia who suffered erectile dysfunction induced by olanzapine 10 mg/day; the erectile dysfunction significantly improved following the treatment of Saikokaryukotsuboreito 7.5 g/day. The other case was a 43-year-old man with schizophrenia who was receiving fluphenazine decanoate at 50 mg/month and had difficulties in ejaculation; add-on of Saikokaryukotsuboreito 7.5 g/day recovered his ejaculatory function. There has been no report on the effectiveness of Japanese herbal medicine formulations for antipsychotic-induced sexual dysfunction. Although the effectiveness of Saikokaryukotsuboreito needs to be tested in systematic clinical trials, this herbal medicine may be a treatment option to consider for this annoying side effect.

Evaluation of changes in monoamine levels and apoptosis induced by cyfluthrin in rats

The aim of this study was to evaluate monoamine and mitochondrial cytochrome c levels and lipid peroxidation in adult male rats treated with cyfluthrin (14 mg kg⁻¹dose; approximately 1/10 of the LD₅₀value) for 14 days. This study also examined cyfluthrin induced-apoptosisviathe signaling proteins Bcl-2, caspase-9 and caspase-3, and possible anti-apoptotic effects of Alfa-basic crystallin.

Behavioral and neurochemical effects of dietary methyl donor deficiency combined with unpredictable chronic mild stress in rats

Methyl donor deficiencies and chronic stress cause depression independently, but their interaction has never been thoroughly evaluated. In our study, methyl donor deficient diet and chronic stress condition consisted respectively of a B2, B9, B12, and choline-free diet and a chronic mild stress procedure. Rats were randomly assigned to six groups with three "diet" conditions (free-feeding, pair-fed and methyl donor deficient diet) and two "stress" conditions (no-stress and stress) and were evaluated in the open-field, the elevated plus-maze and the forced swimming test. After the behavioral evaluation, corticosterone and homocysteine plasma levels were measured and dopamine, DOPAC, serotonin, 5HIAA concentrations were evaluated in several brain areas. Rats given a methyl donor deficient diet for 11 weeks causing elevated plasma homocysteine levels were compared to pair-fed and free-feeding rats with or without unpredictable chronic mild stress. Regardless of stress environmental conditions, the methyl donor deficient diet decreased plasma corticosterone levels and caused disinhibition in the elevated plus-maze condition relative to both control groups. However, stress potentiated the effects of the deficient regimen on rearing in the open-field and climbing in the forced swim test. The dietary changes involved in behavior and plasma corticosterone could be caused by homocysteine-induced decreases in dopamine and 5-hydroxytryptamine metabolites in selective brain regions and it can be noted that regardless of stress-conditions, methyl donor deficient diet decreases DOPAC/dopamine and 5HIAA/serotonin ratios in striatum and hypothalamus and selectively 5HIAA/serotonin ratio in the sensorimotor cortex. Our experimental data is particularly relevant in the context of neuropsychiatric disorders frequently associated with folate deficiency and hyperhomocysteinemia.