Ethanol extracts from Hemerocallis citrina attenuate the decreases of brain-derived neurotrophic factor,TrkB levels in rat induced by corticosterone administration

Ethnopharmacological relevance

Hemerocallis citrina, a traditional herbal medicine, has been used for the improvement of behavioral and emotional status in Eastern-Asia countries.

Aim of the study

Our previous studies have demonstrated that the ethanol extracts of H. citrina flowers (HCE) reversed the behavioral alterations and monoamine neurotransmitter dysfunctions in stressed mice. However, the relation of its antidepressant-like action with neurotrophic molecular expressions remains unknown.

Materials and methods

To clarify this, we explored the effect of HCE (32.5, 65, 130 mg/kg, p.o.) on the behavior, brain-derived neurotrophic factor (BDNF) and its receptor (TrkB) in depression-like rats induced by exogenous administration of the stress hormone corticosterone (40 mg/kg, s.c.).

Results

It was observed that repeated administration of corticosterone induced an elevation on the serum corticosterone levels, which caused the abnormalities observed in the sucrose preference test and forced swimming test (FST). Administration of HCE (65 and 130 mg/kg) reversed the changes above and up-regulated the BDNF and TrkB receptor protein expressions in the brain region of frontal cortex and hippocampus.

Conclusion

These findings confirm that HCE produce an antidepressant-like effect in corticosterone-induced depression-like model of rats and this effect is at least partly mediated by BDNF-TrkB signaling in the frontal cortex and hippocampus.     

Essential oil of Perilla frutescens-induced change in hippocampal expression of brain-derived neurotrophic factor in chronic unpredictable mild stress in mice

Ethnopharmacological relevance

Perilla frutescens (Perilla leaf), a traditional Chinese medicinal herb, has been used for centuries to treat various conditions including depression. A previous study of the authors demonstrated that essential oil of Perilla frutescens (EOPF) attenuated the depressive-like behavior in mice.

Aim of the study

This study was undertaken to explore the dynamic change of behaviors and brain-derived neurotrophic factor (BDNF) expression induced by chronic unpredictable mild stress (CUMS), and improved by EOPF.

Materials and methods

Four separate CUMS experimental groups (1-week, 2-week, 3-week and 4-week treatment) were treated with EOPF (3 mg/kg and 6 mg/kg, p.o.) or fluoxetine (20 mg/kg, p.o.), followed by sucrose preference, locomotor activity, immobility and hippocampal BDNF measurement.

Results

EOPF, as well as fluoxetine, restored the CUMS-induced decreased sucrose preference and increased immobility time, without affecting body weight gain and locomotor activity. Furthermore, CUMS (3 or 4-week) produced a reduction in both BDNF mRNA and protein expression in the hippocampus, which were ameliorated by EOPF (4-week) and fluoxetine (3 or 4-week) treatment.

Conclusion

These results presented here show that BDNF is expressed depending on length of CUMS procedure and EOPF administration. And this study might contribute to the underlying reason for the slow onset of antidepressant activity in clinic.     

Role for monoaminergic systems in the antidepressant-like effect of ethanol extracts from Hemerocallis citrina

Ethnopharmacological relevance

Hemerocallis citrina, a traditional herbal medicine, has been used for the improvement of emotions in Eastern-Asia countries.

Aim of the study

Herein, we explored the antidepressant-like effect and its monoaminergic mechanism of the ethanol extracts from Hemerocallis citrina (HCE).

Materials and methods

Effect of HCE (90, 180 and 360 mg/kg, p.o.) on the immobility time was assessed in the mouse forced swim test (FST) and tail suspension test (TST), and locomotor activity was evaluated in the open-field test (OFT). Additionally, the monoamine neurotransmitters serotonin (5-HT), noradrenaline (NA) and dopamine (DA) levels involved in the antidepressant-like effect of HCE were also measured in the mice brain regions of frontal cortex and hippocampus.

Results

HCE (90, 180 and 360 mg/kg, p.o.) administration significantly reduced the immobility time in both the FST and TST without accompanying changes in locomotor activity in the OFT. The pretreatment of mice with WAY 100635 (0.1 mg/kg, s.c., a 5-HT_1A receptor antagonist), cyproheptadine (3 mg/kg, i.p., a 5-HT₂ receptor antagonist), prazosin (62.5 μg/kg, i.p., an α₁-adrenoceptor antagonist), yohimbine (1 mg/kg, i.p., an α₂-adrenoceptor antagonist), propranolol (5 mg/kg, i.p., a β-adrenoceptor antagonist) or sulpiride (50 mg/kg, i.p., a dopamine D₂ receptor antagonist), but not SCH23390 (0.05 mg/kg, s.c., a dopamine D₁ receptor antagonist) prevented the antidepressant-like effect of HCE (360 mg/kg, p.o.) in the TST. In addition, HCE enhanced 5-HT and NA levels in the frontal cortex and hippocampus as well as elevated DA levels in the frontal cortex.

Conclusion

The results indicate that the antidepressant-like effect of HCE is dependent on the serotonergic (5-HT_1A and 5-HT₂ receptors), noradrenergic (α₁-, α₂- and β-adrenoceptors) and dopaminergic (D₂ receptor) systems as well as the elevation of 5-HT, NA and DA levels in the mouse brain.     

Effects of SYJN,a Chinese herbal formula,on chronic unpredictable stress-induced changes in behavior and brain BDNF in rats

Aim of the study

Suyu-Jiaonang (SYJN) is a Chinese herbal formula that contains four herbs: Bupleurum chinense DC, Curcuma aromatica Salisb., Perilla frutescens (Linn.) Britt., and Acorus tatarinowii Schott. Previous studies conducted in our laboratory have revealed an antidepressant-like effect of the formula in various mouse models of behavioral despair. The present study aimed to investigate whether SYJN could produce antidepressant-like effects in chronic unpredictable stress (CUS)-induced depression model in rats and its possible mechanism(s).

Materials and methods

Rats were subjected to an experimental setting of CUS. The effect of SYJN treatment on CUS-induced depression was examined using behavioral tests including the sucrose consumption and open field tests. The mechanism underlying the antidepressant-like action of SYJN was examined by measuring brain-derived neurotrophic factor (BDNF) protein and mRNA expression in brain tissues of CUS-exposed rats.

Results

Exposure to CUS for 4 weeks caused depression-like behavior in rats, as indicated by significant decreases in sucrose consumption and locomotor activity (assessed in the open field test). In addition, it was found that BDNF protein and mRNA levels in the hippocampus and frontal cortex were lower in CUS-treated rats, as compared to controls. Daily intragastric administration of SYJN (1300 or 2600 mg/kg) during the 4-week period of CUS significantly suppressed behavioral changes and attenuated the CUS-induced decrease in BDNF protein and mRNA levels in the hippocampus and frontal cortex.

Conclusion

The results suggest that SYJN alleviates depression induced by CUS. The antidepressant-like activity of SYJN is likely mediated by the increase in BDNF expression in brain tissues.     

Antidepressant-like effects of Xiaochaihutang in a rat model of chronic unpredictable mild stress

Ethnopharmacological relevance

Xiaochaihutang (XCHT) has been used in China for thousands of years to treat “Shaoyang syndrome”, which involves depressive-like symptoms. However, few studies have investigated its antidepressant effects and pharmacological mechanism of action. The present study was designed to confirm the antidepressant effect of XCHT using a chronic unpredictable mild stress (CUMS) model and explore its potential mechanism of action by investigating the monoamine neurotransmitters (dopamine and 5-hydroxytryptamine) and neurotrophins (BDNF and NGF).

Materials and methods

The CUMS model was established in rats, and the antidepressant effect of XCHT (0.6, 1.7 and 5 mg/kg/day, given by gastric gavage for 4 weeks) was investigated using the open field test (OFT), food consumption test and sucrose preference test. The concentrations of 5-HT and DA in the hippocampus were measured by high performance liquid chromatography with electrochemical detection (HPLC-ECD). The expressions of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), and their receptors tyrosine receptor kinase B (TrkB) and tyrosine receptor kinase A (TrkA) in the hippocampus were measured by immunohistochemical staining analysis.

Results

CUMS caused a significant decrease in OFT, food consumption and sucrose preference in rats, and these depression-like behaviors were significantly improved by XCHT (1.7 and 5 g/kg/day). Moreover, XCHT significantly increased the concentrations of 5-HT (0.6 and 5 g/kg/day) and DA (5 g/kg/day), and improved the BDNF, NGF, TrkB and TrkA expressions in the hippocampus (1.7 and 5 g/kg/day), which was reduced in CUMS rats.

Conclusion

The results obtained suggested that XCHT may have therapeutic actions on depression-like behavior induced by CUMS in rats possibly mediated by increasing the monoamine neurotransmitter concentration and neurotrophin expression in the hippocampus.     

Antidepressant-like effect of the ethanolic extract from Suanzaorenhehuan Formula in mice models of depression

Ethnopharmacological relevance

Suanzaorenhehuan Formula (SHF) is a Chinese herbal formula for the treatment of depression-like disorders. It contains four herbs: Semen Ziziphi spinosae, Cortex Albiziae, Radix Paeoniae Alba and Semen Platycladi. The present study is to investigate the antidepressant-like effect of the ethanolic extract of SHF and its possible mechanisms.

Materials and methods

Mouse models of depression including the tail suspension test (TST), forced swimming test (FST) and chronic unpredicted mild stress (CUMS) were used to evaluate the effects of SHF extract. The mechanisms were examined by measuring monoamine neurotransmitters in mice hippocampus and frontal cortex, testing monoamine oxidase enzyme (MAO) activities in brain of CUMS-exposed mice.

Results

After one-week treatment, SHF extract (50, 100 and 200 mg/kg) induced a significant decrease on immobility time in TST. After two-week treatment, SHF extract (50, 100 and 200 mg/kg) led to a reduction in the immobility period in TST and FST. The 5-HT levels in mice hippocampus were increased only after 200 mg/kg SHF extract treatment. The noradrenaline (NE) levels were increased after 200 mg/kg SHF extract treatment in mice hippocampus and frontal cortex. SHF extract (50, 100 and 200 mg/kg) significantly inhibited monoamine oxidase-A (MAO-A) and monoamine oxidase-B (MAO-B) after 21-day CUMS exposure.

Conclusion

These findings demonstrated that ethanolic SHF extract produced an antidepressant-like effect and the mechanism of action involves the serotonergic, noradrenergic and monoamine oxidase enzyme systems although underlying mechanism still remains to be further elucidated.     

Anti-inflammatory and antioxidant properties of hydroalcoholic crude extract from Casearia sylvestris Sw. (Salicaceae)

Ethnopharmacological relevance

Casearia sylvestris Sw. is widely used in popular medicine to treat inflammatory conditions.

Aim of the study

To investigate the anti-inflammatory and antioxidant properties of hydroalcoholic crude extract (HCE) taken from Casearia sylvestris Sw. (Salicaceae).

Methods and results

The effect of the HCE from this plant (3–300 mg/kg) on the reduction of inflammatory response to carrageenan was investigated in pleurisy in rats (intrapleural, 2% in 0.2 mL) or paw edema in mice (intraplantar, 300 μg/20 μL, right hind paw). The plant anti-inflammatory action was assessed by its capability in inhibiting cell migration, enzymatic activity of myeloperoxidase (MPO) and production of nitrite/nitrate or edema. The in vitro antioxidant activity of this extract against lipid peroxidation and damage to proteins was assessed as possible pathways to contribute as anti-inflammatory mechanisms. Carrageenan-induced hind paw edema (739.3±11.9 μm) was reduced by HCE (30 mg/kg: 462.8±28.38 μm) to similar extents as dexametasone (365.1±16.7). In pleurisy, treatment of the animals with HCE (100 mg/kg: 0.010±0.001 mU/mg of protein) also reduced MPO activity augmented by carrageenan (0.020±0.001 mU/mg of protein) as well as leukocytes migration (carrageenan: 17.8890±2.3900 leukocytes/mL, HCE 100 mg/kg: 7.0880±9631 leukocytes/mL). Significant effects were also observed in animals treated with different doses of HCE in biochemical tests for oxidative stress analysis.

Conclusion

The anti-inflammatory and antioxidant effects of HCE from Casearia sylvestris Sw. suggests a potential therapeutic benefit of this plant in treatment of inflammatory conditions.     

The effect of Chaihu-Shugan-San and its components on the expression of ERK5 in the hippocampus of depressed rats

Ethnopharmacological relevance

Chaihu-Shugan-San (CSS) is a well-known, Chinese traditional medicine used to treat depression. Little is known about the antidepressant mechanism of CSS. The main aims of the this study were to evaluate the antidepressant-like effects of CSS and its components and further explore the CSS?s effect upon signal transduction of extracellular signal-regulated kinase 5 (ERK5) expressions in the hippocampus of rats with depression induced by chronic unpredicted mild stress.

Materials and methods

SD rats were randomly divided into six groups: Normal; Model; CSS; Component I; Component II; and Fluoxetine. Antidepressant-like effects of CSS and two of its constituents, Components I and II in aqueous extract, were assessed using rats exposed to chronic unpredictable mild stress (CUMS) by measuring weight change, observing the open-field test and measuring sucrose water consumption. Antidepressant mechanism were examined by measuring the effect of CSS, and two of its constituents, on extracellular signal-regulated kinase 5 (ERK5) expression, phosphorylation-ERK5 (p-ERK5), and ERK5 mRNA in the hippocampus by using western blotting and Real-time Polymerase Chain Reaction (PCR). Three preparations were prepared: (1) an aqueous extract of CSS (5.9 g/kg·d); (2) Component I (3.3 g/kg·d); and (3) Component II (2.6 g/kg·d). During the 28-day CUMS, the three preparations were intragastrically administered all three preparations. Simultaneously a parallel positive fluoxetine control group was given fluoxetine hydrochloride (1.8 mg/kg·d). Normal and Model groups were intragastrically administered with a isovolumic distilled water (4.5 ml/kg·d).

Results

Depressed rats had decreased weight gain; decreased locomotor activity as measured by the open field test; and reduced sucrose consumption. The rats? hippocampus ERK5 activation was significantly suppressed. CSS reduced the incidence of depressive-like behaviors and increased ERK5 activation in depressed rats at the same rate as fluoxetine. Component I, and II, each had only a partial effect on the depression indicators measured.

Conclusions

CSS aqueous extract has antidepressant-like effects on CUMS-induced depression model rats. The antidepressant effect of CSS is greater than that of either the two separate components measured. CSS?s antidepressant mechanism may be mediated by reversing the stress-induced disruption of ERK5 activity.     

Subchronic administration of Trichilia catigua ethyl-acetate fraction promotes antidepressant-like effects and increases hippocampal cell proliferation in mice

Ethnopharmacological relevance

Trichilia catigua preparations have been popularly used in Brazil as a tonic for the treatment of fatigue, stress, impotence, and memory deficits. We recently demonstrated an antidepressant-like effect of acute administration of the Trichilia catigua ethyl-acetate fraction (EAF) in mice. The aim of the present study was to evaluate whether subchronic Trichilia catigua EAF administration maintains its antidepressant-like effects and whether these effects are related to hippocampal neurogenesis.

Material and methods

Trichilia catigua EAF (200 and 400 mg/kg) was orally administered to mice for 14 day. The animals were tested in the forced swim test (FST) or tail suspension test (TST). After behavioral testing, the animals received bromodeoxyuridine (BrdU; 200 mg/kg, i.p.) and were euthanized 24 h, 7 day, or 15 day later. The brains were assayed for BrdU and doublecortin (DCX) immunohistochemistry to detect cell proliferation/survival and neurogenesis, respectively.

Results

Subchronic administration of 400 mg/kg Trichilia catigua EAF promoted antidepressant-like effects in mice in both the FST and TST. The antidepressant-like effect was accompanied by an increase in cell proliferation in the dentate gyrus (DG) of the hippocampus 24 h after the treatments were discontinued. This proliferative effect, however, did not influence cell survival or neurogenesis because no change in the number of BrdU- or DCX-positive cells was detected 7 or 15 day after the last EAF administration compared with controls.

Conclusions

Trichilia catigua EAF produced antidepressant-like effects and induced hippocampal cell proliferation in mice. The results contribute information on the pharmacological and molecular mechanisms involved in the antidepressant-like effect of Trichilia catigua EAF.     

Vitexin and isovitexin from the Leaves of Ficus deltoidea with in-vivo α-glucosidase inhibition

Ethnopharmacological relevance

The leaves of Ficus deltoidea are used as a traditional medicine by diabetes patients in Malaysia.

Aim of the study

The objective of the study is to identify and evaluate bioactive constituents with in vivo α-glucosidase inhibition.

Materials and Methods

The partitioned extracts, subfractions and pure bioactive constituents were subjected to α-glucosidase inhibition assay. The identified bioactive constituents were administered orally to sucrose loaded normoglycemic mice and induced diabetic rats. The postprandial blood glucose levels were monitored at 30 min interval. Acute toxicity was evaluated in both normoglycemic mice and induced diabetic rats.

Results

Bioactivity guided fractionation led to the isolation of both vitexin (1) and isovitexin (2). Oral administration of 1 mg/kg of either vitexin (1) or isovitexin (2) significantly (p<0.05) reduced the postprandial blood glucose level in sucrose loaded normoglycemic mice at 30 min. The percentage of postprandial blood glucose reduction was highest in sucrose loaded induced diabetic rats administered orally with 200 mg/kg of vitexin (1) or 100 mg/kg of isovitexin (2). Both vitexin (1) and isovitexin (2) did not exert any signs of toxicity at the highest dose of 2 g/kg administered orally to normoglycemic mice and induced diabetic rats.

Conclusion

Both the C-glycosyl bioflavonoids, namely, vitexin (1) and isovitexin (2) exhibited in vivo α-glucosidase inhibition.     

Scorpio and Scolopendra attenuate inflammation and articular damage in rats with collagen-induced arthritis

Ethnopharmacological relevance

Scorpio and Scolopendra (SS) are two traditional Chinese medicines, which are generally used to treat rheumatoid arthritis (RA) in China. However, the mechanism is so far unclear. The purpose of this study was to explore the effects and mechanisms of SS in attenuating inflammation and joint injury in collagen-induced arthritis in rats.

Materials and methods

RA was induced in Wistar rats by injection of collagen, meanwhile, the rats were administrated daily either SS (0.4 g/kg, 0.2 g/kg, and 0.1 g/kg) or vehicle (physiological saline) for 42 days. The therapeutic effect of SS on RA was evaluated by pathological methods. T lymphocyte subsets and anti-collagen type II (CII) antibody were tested in peripheral blood. Tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), interleukin-4 (IL-4) and interleukin-10 (IL-10) were assessed in tissue homogenate of fresh joints.

Results

The inflammation and articular damage in SS powder-treated rats were attenuated significantly. In addition, SS powder was revealed to modulate the equilibrium of T lymphocyte subsets, down-regulate TNF-α and IL-1β, up-regulate IL-4 and IL-10, and significantly suppress the level of anti-CII antibody.

Conclusions

Scorpio and Scolopendra, when used as a combination, reveal desirable effect for treatment of rheumatoid arthritis, and this beneficial effect may be accomplished through normalization of T lymphocyte subsets and the balance of Th1/Th2 cytokines.     

Cycloartane triterpenoid saponins from water soluble of Passiflora edulis Sims and their antidepressant-like effects

Ethnopharmacological relevance

Various species of genus Passiflora have been used as traditional folk medicines owing to their sedative and anti-hypertensive properties. Passiflora edulis Sims most widely grown in the warm temperate for their fragrant fruits and their twigs and leaves are used as a folk medicine for treating both anxiety and nervousness in American countries. The present study was to evaluate the antidepressant-like effect and the active components of this plant.

Materials and methods

The alcohol extracts of the stems (PES, 10 and 2 g/kg of the plant materials) and leaves (PEL, 10 and 2 g/kg of the plant materials) of Passiflora edulis Sims were orally administered to mice for 7 day. The animals were tested in the forced swim test (FST) and tail suspension test (TST). After behavioral assay of ethanol extract, phytochemical research of the stems and leaves (5.7 kg) of Passiflora edulis Sims were developed and further bioactive verification of monomeric compounds were conducted.

Results

There are mainly cycloartane triterpenoids and their saponins isolated from this plant, including two new cycloartane triterpenoid saponins named cyclopassifloside ХII (1) and ХIII (2), together with six known cycloartane triterpenoids, cyclopassifloic acids B and E, cyclopassiflosides II, VI, IX and XI. The ethanol extract of Passiflora edulis Sims together with isolated compounds cyclopassiflosides IX and XI may possess antidepressant-like effect.

Conclusions

Cycloartane triterpenoid was one of the main compositions of Passiflora edulis Sims and possess antidepressant-like activity.     

The effect of Salvia divinorum and Mitragyna speciosa extracts,fraction and major constituents on place aversion and place preference in rats

Ethnopharmacological relevance

Consumer use of botanicals has increased despite, in many instances, the paucity of research demonstrating efficacy or identifying liabilities. This research employed the place preference/aversion paradigm to characterize the psychoactive properties of Salvia divinorum extract (10, 30, 100 mg/kg), salvinorin A (0.1, 0.3, 1.0 mg/kg), Mitragyna speciosa MeOH extract (50, 100, 300 mg/kg), Mitragyna speciosa alkaloid-enriched fraction (12.5, 25, 75 mg/kg) and mitragynine (5, 10, 30 mg/kg) in rats.

Material and methods

Following apparatus habituation and baseline preference scores, male Sprague-Dawley rats were given eight counter-balanced drug versus vehicle conditioning trials followed by a preference test conducted under drug-free states. S(+)-amphetamine (1 mg/kg) served as the positive control (in Exp. 2) and haloperidol (0.8, 1.0 mg/kg) served as the negative control in both studies.

Results

Rats displayed place aversion to both Salvia divinorum and salvinorin A that exceeded that of haloperidol. Rats showed place preference to mitragynine that was similar to that of S(+)-amphetamine. This CPP effect was much less pronounced with the Mitragyna speciosa extract and its fraction.

Conclusions

These findings suggest that both botanicals possess liabilities, albeit somewhat different, that warrant caution in their use.     

Antidepressant activity of Litsea glaucescens essential oil: Identification of β-pinene and linalool as active principles

Ethnopharmacological relevance

Litsea glaucescens (Lauraceae) has been used in Mexican Traditional Medicine to relieve illness related to central nervous system, such as epilepsy, fright and sadness. In this study, L. glaucescens essential oil properties on central nervous system were evaluated in mice using different behavioral tests.

Materials and methods

The essential oil was obtained by hydrodistillation and analyzed by GC/MS. Identification of major compounds was also carried out by comparison with authentic samples. The psychopharmacological profile of L. glaucescens essential oil, and some its major compounds, were evaluated in mice using several experimental models: forced swimming test (FST: Antidepressant-like activity), open field test (OFT: Spontaneous locomotor activity), elevated plus-maze (EPM: Anxiolytic-like activity), exploratory cylinder (ECT: Sedative-like activity), rotarod (motor coordination) and traction performance (myo-relaxant effect) the essential oil and active principles was administered intraperitoneally.

Results

The essential oil showed antidepressant-like activity at doses of 100 and 300 mg/Kg. The monoterpenes β-pinene and linalool were identified as the two main active principles of the essential oil, and showed antidepressant-like and sedative-like activity. Eucalyptol, limonene and α-pinene they did not show antidepressant-like activity, and were not further tested.

Conclusions

L. glaucescens essential oil showed antidepressant activity, β-pinene and linalool were identified as its active principles. These results support the use of L. glaucescens in Mexican Traditional Medicine for the treatment of sadness.     

Evidence of the involvement of the monoaminergic systems in the antidepressant-like effect of Aloysia gratissima

Ethnopharmacological relevance

Aloysia gratissima (Verbenaceae) is an aromatic plant distributed in South America and, employed in folk medicine for the treatment of nervous systems illness, including depression. The neuroprotective and antidepressant-like activities of the aqueous extract of Aloysia gratissima (AE) administered orally has already been demonstrated.In this study the involvement of monoaminergic systems in the antidepressant-like effect of the AE was investigated.

Materials and methods

The implication of the monoaminergic systems in the antidepressant-like activity of Aloysia gratissima was evaluated using different pharmacological antagonists that were administered previously to the acute oral administration of AE (10 mg/kg). The antidepressant-like effect was assessed in the TST and locomotor activity was evaluated in the open-field test in mice.

Results

The anti‐immobility effect elicited by AE in the TST was prevented by the pre-treatment of mice with the antagonists, NAN‐190 (5‐HT_1A receptor), ketanserin (5‐HT_2A/2C receptor), prazosin (α₁‐adrenoceptor), yohimbine (α₂‐adrenoceptor), SCH23390 (dopamine D₁ receptor), or sulpiride (dopamine D₂ receptor).

Conclusions

These results indicate that the antidepressant‐like effect of AE in the TST is dependent on its interaction with the serotonergic (5‐HT_1A and 5‐HT_2A/2C), noradrenergic (α₁ and α₂₋adrenoceptors) and dopaminergic (D₁ and D₂ receptors) systems, suggesting that this specie might act as a new potential resource for developing antidepressants to treat depressive disorders.     

陈皮提取物改善慢性温和不可预知应激小鼠行为和海马BDNF的研究

目的:探讨陈皮提取物对慢性温和不可预知应激(CUMS)抑郁模型小鼠的行为和对脑源性神经营养因子(BDNF)表达水平的影响。方法:ICR小鼠根据糖水偏好百分比随机分为空白对照组、模型对照组、阳性对照盐酸氟西汀20 mg·kg-1组及陈皮提取物100,200,400 mg·kg-1组;除空白对照组外,各组均接受CUMS,造模28 d后开始灌胃给药;各组连续给药28 d后,糖水偏好实验测定糖水偏好百分比、新奇抑制摄食实验测定摄食潜伏期、强迫游泳实验测定不动时间;荧光实时定量PCR和ELISA法测定大脑海马BDNF含量。结果:慢性应激后,模型对照组小鼠糖水偏好百分比减少,摄食潜伏期延长,不动时间增多,海马BDNF含量显著降低;与模型对照组比较,陈皮提取物组能显著改善抑郁小鼠行为学指标,显著提高小鼠海马BDNF含量。结论:陈皮提取物对CUMS模型小鼠有抗抑郁作用,其机制可能与增加海马BDNF有关。     

The effects of Rhizoma drynariae on interleukin-2 and T-lymphocyte levels in rats after severe head injury

Objective

To investigate the effects of Rhizoma drynariae on the levels of interleukin-2(IL-2) and T-lymphocyte subset in rats with severe head injury (SHI).

Methods

72 Sprague Dawley (SD) rats were randomly divided into 3 groups: control group, model group, and R. drynariae group. The experimental group received intragastrical infusions of with aqueous R. drynariae extract four hours after SHI while the other groups were administered with equivalent volumes of physiological saline. Infusions were administered to the 3 groups once a day for 7 d. IL-2 and T-lymphocyte (CD3, CD4, CD8) levels were measured at 24, 72, and 168 h after initial infusion.

Results

The levels of IL-2 and CD4 T cells reduced obviously after 24 h in the model group (P<0.05), but recovered to the levels of the control group after 72 h, and remained elevated after 168 h. In the R. drynariae group, IL-2 and CD4 levels were did not decrease while the level of CD8 T cells was reduced significantly (P<0.05).

Conclusions

R. drynariae can protect against immune dysfunction or improve immunity in rats with severe head injury (SHI).     

Antidepressant-like effect of flavonoids extracted from Apocynum venetum leaves on brain monoamine levels and dopaminergic system

Ethnopharmacological relevance

Apocynum venetum L. (Apocynaceae), a traditional medicinal plant, has been used for the improvement of emotions in Asian countries.

Aim of the study

We explored the antidepressant-like effect and monoaminergic mechanism of a flavonoids extract from Apocynum venetum leaves (AV-extract).

Materials and methods

Effect of AV-extract (25, 50 and 100 mg/kg, i.g.) on mice's immobility time was assessed in forced swim test (FST) and tail suspension test (TST). The locomotor activity was evaluated in the open-field test (OFT). Additionally, the main monoamine neurotransmitters serotonin (5-HT), noradrenaline (NA) and dopamine (DA) and their metabolites 5-hydroxyindole-3-acetic acid (5-HIAA), 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the mouse hippocampus involved in the antidepressant-like effect of AV-extract was also determined by liquid chromatography-electrospray ionization tandem mass spectrometry (LC–ESI–MS–MS).

Results

AV-extract (50 and 100 mg/kg, i.g.) administration significantly reduced the immobility time in both the FST and TST without accompanying changes in locomotor activity in the OFT. It was also found that the AV-extract significantly increased the concentrations of the main neurotransmitters NE and DA along with their respective metabolites DOPAC, HVA in the hippocampus. The antidepressant-like effect of the AV-extract (50 mg/kg, i.g.) was prevented by the pretreatment of mice with SCH23390 (0.05 mg/kg, i.g., a dopamine D₁ receptor antagonist) or sulpiride (50 mg/kg, i.g., a dopamine D₂ receptor antagonist).

Conclusion

The AV-extract produced significant antidepressant-like effects, which likely attribute to increased NE and DA along with their respective metabolites DOPAC, HVA in the mouse hippocampus, and dependent on interaction with dopaminergic (D₁ and D₂ receptor) systems.     

Central nervous system effects and chemical composition of two subspecies of Agastache mexicana; an ethnomedicine of Mexico

Ethnopharmacological relevance

Agastache mexicana subspecies mexicana (Amm) and xolocotziana (Amx) are used in Mexican traditional medicine to relief cultural affiliation syndromes known as “susto” or “espanto”, for “nervous” condition, and as a sleep aid. Despite its intensive use, neuropharmacological studies are scarce, and the chemical composition of the aqueous extracts has not been described. Aims of the study are: (1) To analyze the chemical composition of aqueous extracts from aerial parts of Amm and Amx. (2) To evaluate the anxiolytic-like, sedative, antidepressant-like effects. (3) Analyze the general toxic effects of different doses.

Materials and methods

Anxiolytic-like and sedative effects were measured in the avoidance exploratory behavior, burying behavior and the hole-board tests. The antidepressant-like actions were studied in the forced swimming and tail suspension tests. Finally, general activity and motor coordination disturbances were evaluated in the open field, inverted screen and rota-rod tests. The acute toxicity of Amm and Amx was determined by calculating their LD₅₀ (mean lethal dose). The chemical analyses were performed employing chromatographic, photometric and HPLC–ESI-MS techniques.

Results

Low doses of Amm and Amx (0.1σ1.0 mg/kg) induced anxiolytic-like actions; while higher doses (over 10 mg/kg) induced sedation and reduced the locomotor activity, exerting a general inhibition in the central nervous system (CNS).

Conclusions

Results support the use of Amm and Amx in traditional medicine as tranquilizers and sleep inducers. Additionally, this paper contributes to the knowledge of the chemical composition of the aqueous extracts of these plants.