Central nervous system activity of the hydroalcoholic extract of Casimiroa edulis in rats and mice

In order to evaluate the effects produced by the hydroalcoholic extract of leaves from Casimiroa edulis on the central nervous system, different behavioral tests and animal models of depression and anxiety were performed. The extract was administered intraperitoneally in male and female rats and tested on spontaneous motor activity, locomotor activity, exploration of an elevated plus-maze (EPM) and in the forced swimming test (FST). In addition, the extract was administered orally in male and female mice and evaluated in the following tests: general observation, pentobarbital-induced hypnosis, EPM, rota-rod, hole-board, and marble-burying. The results revealed that, in rats, the extract caused considerable reduction of locomotor and exploratory activities and increased the exploration of the EPM open arms in a similar way that diazepam. In the FST, the extract was as effective as fluoxetine in inducing shortening of immobility, along with a significant increase on climbing duration. On the other hand, in mice, the extract prolonged pentobarbital-induced hypnosis, increased exploration of the EPM open arms and partially protected from the pentylenetetrazol-induced convulsions. No significant effect was evident on motor coordination, hole-board and marble-burying tests. These results suggest that the hydroalcoholic extract of Casimiroa edulis may contain sedative principles with potential anxiolytic and antidepressant properties, which need further investigation.     

Antidepressant-like effect of Tagetes lucida Cav. extract in rats: involvement of the serotonergic system

It has been demonstrated that the decoction of the aerial parts of Tagetes lucida Cav. produces an antidepressant effect during the forced swimming test (FST) in rats. The aim of this study was to evaluate the effect of different organic extracts and one aqueous extract of the aerial parts of T. lucida on the FST. In addition, the possible involvement of the serotonergic system in the antidepressant-like effect of T. lucida in the FST was evaluated, as was its potential toxicological effect. The different extracts of T. lucida (methanol, hexane, dichloromethane and aqueous, 10 and 50 mg/kg), as well as fluoxetine (FLX, 5 mg/kg), were administered per os (p.o.) to rats for 14 days. All animals were subjected to the FST. Only the aqueous extract of T. lucida at a dose of 50 mg/kg significantly reduced immobility behavior and increased swimming in the FST, similar to FLX. Later, the aqueous extract of T. lucida (50mg/kg) was administered for 1, 7 and 14 days. An antidepressant effect was observed after 7 days of treatment. To evaluate the participation of the serotoninergic system, the animals were pretreated with PCPA, an inhibitor of serotonin synthesis (100 mg/kg/day for 4 consecutive days). The animals were treated with the aqueous extract of T. lucida (50 mg/kg) and FLX (5 mg/kg) 24 h after the final injection and were then subjected to the FST. Pretreatment with PCPA inhibited the antidepressant effect of both T. lucida and FLX. Finally, T. lucida was administered p.o. and intraperitoneal route to evaluate its acute toxicological effect. The aqueous extract of T. lucida, administered p.o., did not produce lethality or any significant changes in behavior. In conclusion, the aqueous extract of T. lucida manifested an antidepressant-like effect in the FST mediated by the serotonergic system, with no adverse effects when administered p.o.     

Anxiolytic effects of Salvia reuterana Boiss. on the elevated plus-maze model of anxiety in mice

The anxiolytic and sedative effects of hydroalcoholic extract (HE) of Salvia reuterana Boiss. was evaluated in mice. The HE of Salvia reuterana (100 mg/kg), increased the percentage of time-spent and the percentage of arm entries in the open arms of the elevated plus-maze. Spontaneous locomotor activity count measured in 15 min of the test was significantly decreased in animals pretreated with diazepam and 100 mg/kg of Salvia reuterana extract. Results of the present study provide support for the traditional usage of Salvia reuterana as a sedative and anxiolytic medicinal plant.     

Pharmacological study on antidepressant activity of 50% ethanol extract of a formulated ayurvedic product in rats

The effects of 50% ethanol extract of one formulated ayurvedic product, consisting of a mixture of medicinal plant species, was investigated on behavioral despair test (forced swimming test, FST), central dopaminergic and serotonergic activity in rats. The effects on the forced swimming test were assessed along with the levels of dopamine (DA), serotonin (5-HT) and its metabolites homovanillic acid (HVA) and 5-hydroxyindoleaceticacid (5-HIAA) in striatum, frontal cortex, hippocampus, hypothalamus and brain stem after 21 days of chronic oral administration of the extract (500 and 1500 mg/kg-body weight). The extract significantly increased climbing behavior at 500 mg/kg and increased swimming behavior by reducing immobility time at 1500 mg/kg when compared with the control group in forced swimming test (P<0.05). This showed that the active substances present in 50% ethanol extract of the ayurvedic preparation possess antidepressant activity and their specificity towards particular behavior, depends on the concentration of the extract. Further it showed that the enhancement of active behavior in FST is not due to generalized motor activity. The neurochemical estimations revealed the swim stressor inducing alterations in the levels of DA, 5-HT and their metabolites HVA and 5-HIAA in the brain regions assayed as compared with the non-stressed control rats. These changes were prevented extract treated rats. The 500 mg/kg extract treated group had significantly increased the levels of DA in frontal cortex, hypothalamus and hippocampus whereas the 5-HT in hypothalamus (P<0.05). However, there were no significant changes in the levels of HVA and 5-HIAA. These behavioral and biochemical results indicate antidepressant properties of the extract, which may be mediated by the dopaminergic and serotonergic mechanisms in rat brain.     

Evaluation of antidepressant activity of methanolic and hydroalcoholic extracts of Acorus calamus L. rhizome through tail suspension test and forced swimming test of mice

ObjectiveAcorus calamus (AC) L. (Araceae) is an annual semi-aquatic and aromatic plant found in Europe, North America and Asia. Its rhizomes are often used by Native Americans, Americans, and Chinese as well as by other cultures. Ethnobotanical studies and documents have shown their use in various disease treatments, such as insomnia, mental disorders, diabetes mellitus, epilepsy, inflammation, asthma, neuropathic pain, and diarrhea. In this study, the antidepressant activity of methanolic and hydroalcoholic extracts of the AC rhizome part in mice was investigated.MethodsThree doses of methanolic extract of AC rhizome (MEACR) (25, 50 and 100 mg/kg b.wt), three doses of hydroalcoholic extract of AC rhizome (HAACR) (100, 200 and 400 mg/kg b.wt), and standards (imipramine, 15 mg/kg b.wt and fluoxetine, 20 mg/kg b.wt) was daily oral administration to the mice for consecutive 14 days. The extract effect on the immobility time was monitored by a tail suspension test (TST) and a forced swimming test (FST). Monoamine oxidase (MAO) levels were also analyzed using standard methods.ResultsThe optimum antidepressant activity was viewed at 100 mg/kg b.wt of MEACR extract and 400 mg/kg b.wt of HAACR extract with 23.82% and 20.59% immobility period reduction, respectively. Besides, the extracts weakened the FST-induced elevation of MAO activity significantly and returned to near-normal levels of neurotransmitters in the brain. 100 mg/kg b.wt or above of MEACR extract significantly prevented the MAO-A and MAO-B activities in mice brain at a dose-dependent fashion. But, just 400 mg/kg b.wt of HAACR extract prevented the activity of MAO-A and MAO-B. Fluoxetine and imipramine showed a tendency to prevent the activity of MAO-A and MAO-B.ConclusionThis study suggests that AC rhizome extract mediated antidepressant activity by modulating the central neurochemical and hypothalamic-pituitary-adrenal (HPA) axis in response to FST and TST-induced stress. Therefore, AC rhizome extract can be used as a valuable plant supplement to treat depressive disorders.     

Behavioral and biochemical studies of total furocoumarins from seeds of Psoralea corylifolia in the forced swimming test in mice

The behavioral and biochemical effects of total furocoumarins from seeds of Psoralea corylifolia (TFPC) were investigated in the forced swimming test (FST) in mice in comparison with amitriptyline and fluoxetine. TFPC was found to reduce the duration of immobility in the FST without accompanying changes in ambulatory, rearing and grooming behaviors in the open-field test. After a 3-day treatment, TFPC at the doses from 7.5 to 100 mg/kg significantly decreased the immobility time. The efficacy of the higher doses exceeded that of amitriptyline at 10 and 20 mg/kg and fluoxetine at 13 mg/kg. After a 7- or 14-day treatment, TFPC exhibited an inverted U-shaped dose-response relations, maximal effects were obtained at 30 mg/kg, when the efficacy appeared to be more than that of amitriptyline and fluoxetine. In animal brain and liver, after 14-day treatment, TFPC significantly inhibited monoamine oxidase A and B (MAO-A and MAO-B) activities with an inverted U-shaped dose-dependent relationship in brain, and with dose-dependent relationship in liver. Moreover, TFPC was more potent for MAO-B than MAO-A, except at the lowest dose, which was similar to amitriptyline and fluoxetine. In addition, TFPC blocked plasma elevated cortisol level, an indicator of the hypothalamic-pituitary-adrenal (HPA) axis. TFPC significantly decreased liver superoxide dismutase (SOD) activity and malondialdehyde (MDA) level, two indicators of oxidative stress, providing an inverted U-shaped dose-dependent relationship. These results suggest that TEPC possesses potent antidepressant properties that are mediated via MAO activity, HPA axis action and oxidative stress in the FST in mice.     

Anxiolytic effects of Stachys lavandulifolia Vahl on the elevated plus-maze model of anxiety in mice

Interest in alternative medicine and plant-derived medications that affect the "mind" is growing. The aim of the present study was to investigate the effects of a hydroalcoholic extract and essential oil of Stachys lavanduifolia Vahl on the elevated plus-maze (EPM) model of anxiety. The Stachys lavandulifolia extract or its essential oil was administered intraperitoneally to male TO mice, at various doses, 30 min before the behavioral evaluation. The extract of Stachys lavandulifolia at the dose of 100 mg/kg increased the percentage of time spent and the percentage of arm entries in the open arms of the EPM and decreased the percentage of time spent and the percentage of arm entries in the closed arms of the EPM. The plant extract at doses lower than 100 mg/kg had no significant effects on any of the parameters measured on the EPM. This dose of the plant extract prolonged the ketamine-induced sleeping time, and decreased the locomotor activity in mice. These results suggested that the extract of Stachys lavandulifolia possessed anxiolytic effect with relatively lower sedative activity than diazepam. The essential oil of Stachys lavandulifolia, however, at doses of up to 100 mg/kg did not have any significant effects on the mice behaviour on the EPM.     

Antinociceptive,neurobehavioral and antioxidant effects of Eupatorium triplinerve Vahl on rats

Ethnopharmacological relevance

Eupatorium triplinerve Vahl belongs to the Asteraceae family, popularly known as Japana. It is a perennial shrub native to Amazon rainforests of South America. Its leaves are used through infusions, decoctions, baths, and tea. It is largely used in Brazilian folk medicine as sedative, febrifuge, stimulant, tonic and anti-inflammatory.

Aim of the study

The present study evaluated the putative effects of Eupatorium triplinerve on the central nervous system (CNS), including locomotor and anxiety activity, depression-like behavior, and antinociception and oxidative stress.

Materials and methods

Two-month-old male Wistar rats (n=7–10 rats/group) and Swiss male and female mice of the species Mus musculus (n=7–10 per group) were administered with 100 mg/kg, 200 mg/kg, 400 mg/kg, 600 mg/kg, and 800 mg/kg of hydroalcoholic extracts of Eupatorium triplinerve (HEET). The behavioral assays included open-field (OF), elevated Plus-maze (EPM), and forced swimming tests (FS). The antinociceptive activity was verified using chemical (acetic acid and formalin) and thermal (hot plate) models of nociception. The oxidative stress levels were measured in rat blood samples after behavioral assays and Trolox equivalent antioxidant capacity (TEAC), nitric oxide and malondialdehyde (MDA) levels were measured in vivo.

Results

Oral pretreatment with HEET reduced the locomotion in OF test (200–800 mg/kg), increased central locomotion and open arms entries in the OF and EPM tests, respectively (600–800 mg/kg), and decreased the immobility time in the FS (200–800 mg/kg). It also reduced the writhing number evoked by acetic acid injection (200–800 mg/kg) and licking time in the first phase of the formalin test (400–800 mg/kg). In the oxidative stress assays, the extract decreased TEAC, Nitric Oxide and MDA levels in response to swimming stress induced in rats.

Conclusions

These results were indicative for the first time that Eupatorium triplinerve exerted mild sedative, anxiolytic and antidepressive effects on the CNS. Antinociceptive effects not related to opioid system and antioxidant activity were also observed. These results support the ethnopharmacological use of Eupatorium triplinerve in popular medicine.     

CNS pharmacological effects of the hydroalcoholic extract of Sida cordifolia L. leaves

Sida cordifolia L. (Malvaceae), known as "malva branca", is a plant used in the popular medicine for the treatment stomatits, of asthma and nasal congestion. This work researched the acute toxicity of Sida cordifolia and its action on the central nervous system (CNS) because no data in the literature have been found about of pharmacological activity of this plant in the CNS. The hydroalcoholic extract of Sida cordifolia leaves (HESc) was used and the psychopharmacology approach began with the determination of LD(50), where a low toxicity was observed in mice. Depressive activity on CNS was demonstrated by several alterations in mice's behavior in the pharmacological screening. In the motility test, the HESc showed significant reduction of spontaneous activity at a dose of 1000 mg/kg (i.p.) at 30 and 60 min. The same form the HESc also decreased the ambulation and rearing in open-field test at 30, 60 and 120 min at a dose of 1000 mg/kg (i.p.).     

Anxiolytic and antidepressant activities of Pelargonium roseum essential oil on Swiss albino mice: Possible involvement of serotonergic transmission

The anxiolytic and antidepressant activities of the Reunion Geranium (Pelargonium roseum Willd) essential oil (EO) were evaluated in male Swiss albino mice by intraperitoneal administration of 10, 20, and 50 mg/kg bw using elevated plus maze (EPM), open‐field test (OFT), and forced swimming test (FST). Moreover, we evaluated whether the 5‐HT_1A and GABA_A–benzodiazepine receptor systems are involved in the anxiolytic effects through the coadministration of WAY‐100635 (a selective 5‐HT_1A receptor antagonist) and flumazenil (an antagonist of benzodiazepine). GC–MS revealed the monoterpene alcohols citronellol (35.9%) and geraniol (18.5%) as the main components of the P. roseum EO. EO was effective in increasing the total number of entries and time spent in the open arms of EPM whereas number of rearing in OFT was significantly decreased in comparison with the control. In the FST, immobility time decreased in EO treated mice. Pretreatment with WAY‐100635, but not Flumazenil, was able to reverse the effects of the EO in the EPM and FST, indicating that the EO activity occurs via the serotonergic but not GABAergic transmission. Overall, results of this work showed significant anxiolytic and antidepressant activity of P. roseum EO and confirmed the traditional uses of Pelargonium species as calming agents.     

Neuropharmacological in vivo effects and phytochemical profile of the extract from the aerial parts of Heteropterys brachiata (L.) DC. (Malpighiaceae)

Ethnopharmacological relevance

Heteropterys brachiata is a plant species that has been used in traditional Mexican medicine for the treatment of nervous disorders.

Aim of the study

To evaluate the anxiolytic, anticonvulsant, antidepressant and sedative effects produced by the methanolic extract of Heteropterys brachiata (HbMeOH) in ICR mice. Additionally, we determine the acute toxicity profiles of the extract and the presence of its main constituents.

Material and methods

The neuropharmacological effects of the extract were evaluated using a variety of models, such as the elevated plus maze (EPM), the forced swimming test (FST), the pentobarbital potentiation test (PTBt), pentylenetetrazole-induced seizures test (PTZt), and the open field test (OFT). HPLC was employed for obtention of phytochemical profile.

Results

HbMeOH produced a significant antidepressant effect in FST at 500 and 750 mg/kg doses, while doses from 500 to 1500 mg/kg exhibited a clear dose-dependent anxiolytic activity in EPM. A dose of 500 mg/kg showed a significant anticonvulsant activity in PTZt and an absence of sedation effects in PTBt. The main compounds of HbMeOH were chlorogenic acid and chlorogenic acid methyl ester, as well as less abundant terpene-type compounds. Furthermore, the extract was either safe with no deaths in mice treated orally with 2000 mg/kg.

Conclusions

HbMeOH extract which contains mainly hydroxycinnamic acids and triterpene-type compounds, possesses antidepressant, anxiolytic and anticonvulsive properties and can be considered safe or of low toxicity when orally administrated. These findings lend pharmacological justification to the traditional use of Heteropterys brachiata in the treatment of nervous disorders.     

Studies on neuropharmacological profile of ethanol extract of Moringa oleifera leaves in mice

Ethnopharmacological relevance

Moringa oleifera (family Moringaceae), commonly called Horseradish or tree of life, is traditionally used for the treatment of epilepsy and neurologic conditions.

Aim of the study

The objective of this study is to investigate the neurobehavioural and anticonvulsant properties of the ethanol extract from the leaves of Moringa oleifera.

Materials and methods

Neurobehavioural properties were evaluated using the open field, hole board, Y-maze, elevated plus maze (EPM) and pentobarbitone-induced hypnosis. Pentylenetetrazole (leptazol), picrotoxin and strychnine induced convulsion tests were used to investigate the anti-convulsive actions of Moringa oleifera.

Results

The result showed that the extract (250–2000 mg/kg) caused a significant dose-dependent decrease in rearing, grooming, head dips and locomotion (P<0.001). It also enhanced learning and memory and increased anxiogenic effect. In addition, the extract (2000 mg/kg) protected mice against pentylenetetrazol induced convulsion, but has no effect on picrotoxin and strychnine induced convulsion. The effects of the extract in the various models were comparable to those of the standard drugs used except in Y-maze, EPM and picrotoxin and strychnine induced convulsion. The LD₅₀ obtained for the acute toxicity studied using oral route of administration was >6.4 g/kg.

Conclusion

The findings from this study suggest that the ethanol extract of Moringa oleifera leaves possesses CNS depressant and anticonvulsant activities possibly mediated through the enhancement of central inhibitory mechanism involving release γ-amino butyric acid (GABA). The results partially justified the traditional use of the extract for the treatment of epilepsy.     

Effect of lyophilized extracts from guaraná seeds [Paullinia cupana var. sorbilis (Mart.) Ducke] on behavioral profiles in rats

The aim of the present study was to investigate the pharmacological properties of the crude lyophilized extract (EBPC) of Paullinia cupana seeds (guaraná) and the semi-purified extracts (EPA and EPB) after acute or chronic administration by the oral route in rats. Anxiolytic-like, antidepressant-like and motor stimulant effects were evaluated using the plus maze (PMT), forced swimming (FST) and open field (OFT) tests, respectively. Acute or chronic administration of EBPC (3.0, 30.0 or 60.0 mg/kg) did not alter the percentage of entries or the time spent in the open arm in the PMT. In the FST, chronic treatment with 30.0 mg EBPC/kg and 4.0 mg EPA/kg extract decreased the immobility time similarly to the antidepressant reference drug, imipramine (20.0 mg/kg). Locomotor activity in the OFT was not increased by these extracts. Caffeine (10.0 mg/kg) significantly reduced the immobility time in the FST, but increased locomotor activity in the OFT, indicating psychostimulant activity. The EPB extract did not induce any effect after acute or chronic treatment in the different models used. The present results suggest that the crude EBPC extract and EPA extract produced an antidepressant-like effect after long-term administration.     

高度富集黄酮类成分的贯叶连翘提取物抗抑郁作用

目的探讨贯叶连翘提取物中高度富集的黄酮类成分的抗抑郁作用。方法采用小鼠强迫游泳实验、小鼠悬尾实验、开野实验和拮抗利血平所致的体温降低实验,分别以小鼠不动时间、自主活动数和体温下降值作为评价指标。结果在强迫游泳和悬尾实验中,40,80,160,240mg/kg剂量组贯叶连翘提取物均能显著缩短小鼠不动时间,20mg/kg剂量组无显著性差异;开野实验结果表明给药后小鼠的自主活动不同程度地减少;在利血平拮抗实验中,30,60,120mg/kg剂量组在3h,4h和5h各时间点体温下降值与模型对照组相比有显著性差异,240和480mg/kg两剂量组在各测定时间点体温下降值与模型对照组相比均有显著性差异。结论高度富集总黄酮的贯叶连翘提取物(弃除贯叶金丝桃素)有抗抑郁作用。     

Pharmacological in vivo test to evaluate the bioavailability of some St John's Wort innovative oral preparations

In this study, the optimisation of biopharmaceutical properties of a dried commercial extract of St John's Wort were evaluated employing the in vivo forced swimming test (FST). Three new dosage forms containing beta-cyclodextrin and surfactants (SDS, ASC8) were compared in the FST with the commercial extract. The commercial extract showed antidepressant activity in mice after 60 min at a dosage of 100 mg/kg. The same antidepressant activity appeared in 30 min with a micellar solution of SDS containing the same quantity of extract (100 mg/kg), while with micelles of ASC8 the effect appeared at 15 min and with a dosage of 30 mg/kg. In the case of beta-cyclodextrin the best results were obtained at 30 min, administering 60 mg/kg of the extract. Finally, the influence of the formulations on the water solubility of the constituents of the extract is reported. The tensides dramatically enhanced solubility, in particular that of the more lipophilic compounds, in the case of beta-cyclodextrin this effect was very pronounced for flavonoids and biapigenin, lower for hypericins and practically insignificant for hyperforins.     

Behavioural effects of Passiflora incarnata L. and its indole alkaloid and flavonoid derivatives and maltol in the mouse

Lyophilised hydroalcoholic and aqueous extracts of the aerial parts of Passiflora incarnata L. (Passifloraceae) (Passion-flower), as well as chemical constituents of the plant, indole alkaloids (harman, harmin, harmalin, harmol, and harmalol) maltol and flavonoids (orientin, isoorientin, vitexin and isovitexin) were assessed for behavioral effects in mice. The accordance with the traditional use of P. incarnata, psychotropic properties were confirmed by some behavioral tests in mice. The anxiolytic properties of hydroalcoholic extract were confirmed at 400 mg/kg by the increase of rears and steps climbed in the staircase test (non-familiar environmental test), and the increase in locomotion and time spent in light side in the light/dark box choice test (non-familiar environmental test). The sedative properties of aqueous extract were confirmed at 400 g/kg by decrease of rears and steps climbed in the staircase test and the decrease of rears and locomotion in the free exploratory test. Moreover, the aqueous extract induced sleep in mice after treatment with a sub-hypnotic dose of pentobarbital.     

灵芝促学习记忆及抗衰老作用实验研究

目的 :研究灵芝对血虚小鼠自发行为、学习记忆及抗衰老作用。方法 :血虚小鼠用灵芝水煎剂 ,对照组小鼠用生理盐水灌胃 ,连续 13d,期间进行小鼠开场行为和学习记忆的测定 ,以及小鼠应急力竭游泳后 2 4 h分别对小鼠脑、肝的超氧化物歧化酶 (SOD)的活性 ,脑、肝、心、脾、肌的丙二醛 (MDA)、脂褐素 (L PF)含量进行测定。结果 :灵芝对血虚小鼠开场行为中的理毛次数有显著影响 (P<0 .0 5 ) ,但对移动隔数、站立次数以及学习记忆未产生显著影响。灵芝能显著提高血虚小鼠脑、肝中的 SOD活性 (P<0 .0 5 ) ,显著降低脑、肝、心、脾、肌的 MDA、L PF的含量 (P<0 .0 5 )。结论 :灵芝可促进血虚小鼠的自发活动 ,且抗衰老作用显著     

Anxiolytic-like actions of leaves of Casimiroa edulis (Rutaceae) in male Wistar rats

Anxiolytic-like actions of an aqueous extract of the leaves of Casimiroa edulis (Ce) La Llave ex Lex. (Rutaceae) were studied in male Wistar rats in the elevated plus-maze test, whether effect on locomotion were studied in the open-field task, and its possible antidepressant-like actions in the forced swimming task. In the elevated plus-maze test, diazepam (Dz) (1.30 mg/kg; P < 0.05) and Casimiroa edulis (25.0 mg/kg, P < 0.05; 35.0 mg/kg, P < 0.05) increased open arms exploration (i.e., anxiolytic-like action). Doses of 45.0 mg/kg (P < 0.05) and 55.0 mg/kg (P < 0.05) of Casimiroa edulis reduced locomotion in the elevated plus-maze test and in the open-field test. In the forced swimming task, desipramine (dmi) (32.0 mg/kg; P < 0.05) reduced immobility (i.e., antidepressant-like action). Conversely, as compared to control rats, neither diazepam (Dz) (1.30 mg/kg) nor Casimiroa edulis (25.0 mg/kg) modified immobility in the forced swimming task. However, diazepam (P < 0.05) or Casimiroa edulis (P < 0.05), when co-administered, canceled the antiimmobility actions of desipramine. In conclusion, the leaves of Casimiroa edulis (Rutaceae) produced anxiolytic-like actions in male Wistar rats, with several side actions, namely, reduced locomotion and neutralization of the antidepressant-like actions of desipramine.     

Psychopharmacological screening of Pfaffia glomerata Spreng. (Amarathanceae) in rodents

The alcoholic extract of Pfaffia glomerata roots (100, 500, 1000 mg/kg, intraperitoneally (i.p.), and 500, 1000, 1500 mg/kg, per os) was studied in several behavioral animal models for the evaluation of central activity: open field, barbiturate sleeping time, pentilenotetrazole (PTZ)-induced convulsions, elevated plus-maze, step-down inhibitory avoidance and forced swimming test. The acute treatment (500 mg/kg, i.p.) interfered with the open-field habituation, decreased sleep latency and increased barbiturate-induced sleeping time, protected partially the animals of PTZ-induced convulsions, decreased the memory retention in step-down inhibitory avoidance, and did not have an important effect in the elevated plus-maze test and forced swimming test. The same extract at 1000 mg/kg per os did not cause any effect in barbiturate sleeping time and pentilenotetrazole-induced convulsions models. Thus, the effect on the memory was deeper evaluated in the step-down inhibitory avoidance task. When administered by intraperitoneal route, the extract showed a dose-dependent effect causing full amnesia at 1000 mg/kg. On the other hand, when it was given by oral route at 500, 1000 and 1500 mg/kg, no influence on the memory retention was observed. These results suggest that the alcoholic extract of P. glomerata roots presents different effects depending on the route of administration: by i.p route, it seems to be a central nervous system depressant agent; by oral route, it seems to be ineffective, at least in the tested doses.     

Antidepressant-like effects of the active acidic polysaccharide portion of ginseng in mice

Aim of the study

The biological of activity of Panax ginseng C.A. Meyer (ginseng) is complex but some of its known effects are related to affective and anxiety disorders, including the enhancement of neuroprotection, cellular resilience and plasticity. Whereas such effects suggest that ginseng might have antidepressant activity, previous studies show incongruent results. The sources of contrasting results might be many but one possibility is the utilization of different ginseng preparations in different studies. The current study was therefore designed to examine the effects of a very specific component of ginseng extract, the acidic polysaccharide portion of the plant (WGPA), containing arabinogalactan, type-I rhamnogalacturonan (RG-I)- and homogalacturonan (HG)-rich pectins.

Materials and methods

WGPA was extracted from ginseng roots and administered orally to mice at 100 mg/kg and 200 mg/kg doses. WGPA was administered chronically, once daily for 1 week before the start of experiments and throughout the behavioral tests battery. Mice were tested for spontaneous activity, social interactions, anxiety-like behavior in the elevated plus-maze (EPM) and despair-like behavior in the forced swim test (FST).

Results

WGPA had no effects on spontaneous activity or behavior in the EPM. In contrast, 100 mg/kg (but not the 200 mg/kg) WGPA significantly reduced immobility time in the FST and both doses significantly increased social interactions and decreased aggressive behaviors in mice.

Conclusion

These results suggest that chronic WGPA treatment might have antidepressant-like effects that are unrelated to generalized behavioral changes. The results are discussed in the context of the known ability of the active ingredients of ginseng to increase neuroprotection, similar to many of the current antidepressant and mood stabilizing drugs.