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

Objective:Acorus 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.Methods:Three 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.Results:The optimum antidepressant activity was viewed at 100 mg/kg b.wt of MEACR extract and400 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.Conclusion:This 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 TSTinduced stress.Therefore,AC rhizome extract can be used as a valuable plant supplement to treat depressive disorders.

Neuronal protein-tyrosine phosphatase 1B hinders sensory-motor functional recovery and causes affective disorders in two different focal ischemic stroke models

Ischemic brain injury causes neuronal death and inflammation.Inflammation activates protein-tyrosine phosphatase 1B(PTP1B).Here,we tested the significance of PTP1B activation in glutamatergic projection neurons on functional recovery in two models of stroke:by photothrombosis,focal ischemic lesions were induced in the sensorimotor cortex(SM stroke)or in the peri-prefrontal cortex(peri-PFC stroke).Elevated PTP1B expression was detected at 4 days and up to 6 weeks after stroke.While ablation of PTP1B in neurons of neuronal knockout(NKO)mice had no effect on the volume or resorption of ischemic lesions,markedly different effects on functional recovery were observed.SM stroke caused severe sensory and motor deficits(adhesive removal test)in wild type and NKO mice at 4 days,but NKO mice showed drastically improved sensory and motor functional recovery at 8 days.In addition,peri-PFC stroke caused anxiety-like behaviors(elevated plus maze and open field tests),and depression-like behaviors(forced swimming and tail suspension tests)in wild type mice 9 and 28 days after stroke,respectively,with minimal effect on sensory and motor function.Peri-PFC stroke-induced affective disorders were associated with fewer active(FosB+)neurons in the PFC and nucleus accumbens but more FosB+neurons in the basolateral amygdala,compared to sham-operated mice.In contrast,mice with neuronal ablation of PTP1B were protected from anxiety-like and depression-like behaviors and showed no change in FosB+neurons after peri-PFC stroke.Taken together,our study identifies neuronal PTP1B as a key component that hinders sensory and motor functional recovery and also contributes to the development of anxiety-like and depression-like behaviors after stroke.Thus,PTP1B may represent a novel therapeutic target to improve stroke recovery.All procedures for animal use were approved by the Animal Care and Use Committee of the University of Ottawa Animal Care and Veterinary Service(protocol 1806)on July 27,2018.

Assessment of commonly used tests in experimental depression studies according to behavioral patterns of rodents

Considering the main factor that causes or triggers depression in humans is stress.Several stress factors are applied to form depression-like symptoms in rodents.Depression tests are used to analyze the nature and patterns of depression.Well-founded modeling and versatile evaluation of tests are necessary to investigate a hypothesis that is related to depression.It is impossible to model or test all aspects of depression in humans by using experimental animals.As a result,the aims of the study should be determined specifically in depression models.The correct interpretation of the tests that are suitable for these aims is indispensable for the reliability of the data.To achieve this goal,the biological basis of the depression-related behaviors of animals should be well known.In this review,model and test concepts related to depression are discussed and behavioral patterns of rodents are explained with several examples.

A Network Pharmacology-Based Study on Antidepressant Effect of Salicornia europaea L.Extract with Experimental Support in Chronic Unpredictable Mild Stress Model Mice

Objective:To investigate the pharmacodynamic material basis,mechanism of actions and targeted diseases of Salicornia europaea L.(SE)based on the network pharmacology method,and to verify the antidepressant-like effect of the SE extract by pharmacological experiments.Methods:Retrieval tools including Chinese medicine(CM),PubMed,PharmMapper,MAS 3.0 and Cytoscape were used to search the components of SE,predict its targets and related therapeutic diseases,and construct the"Component-TargetPathway"network of SE for central nervous system(CNS)diseases.Further,protein-protein interaction(PPI)network,Kyoto Encyclopedia of Genes and Genomes(KEGG)and Gene Ontology(GO)function annotation of depression-related targets were analyzed to predict the antidepressant mechanism of SE.Chronic unpredictable mild stress(CUMS)model was used to construct a mouse model with depression-like symptoms.And the animals were randomly divided into 6 groups(n=10)including the normal group(nonstressed mice administered with distilled water),the CUMS group(CUMS mice administered with distilled water),the venlafaxine group(CUMS mice administered with venlafaxine 9.38 mg/kg),SE high-,medium-,and low-dose groups(CUMS mice administered with SE 1.8,1.35 and 0.9 g/kg,respectively).Then some relevant indicators were determined for experimental verification by the forced swim test(FST),the tail suspension test(TST)and open-field test(OFT).Dopamine(DA)concentration in hippocampus and cerebral cortex,IL-2 and corticosterone(CORT)levels in blood,and nuclear factor E2 related factor 2(Nrf2),kelch-like epichlorohydrin related protein 1(Keap1),NAD(P)H dehydrogenase[quinone]1(NQO1)and heme oxygenase-1(HO-1)levels in mice were measured by enzyme linked immunosorbent assay(ELISA)and Western blot respectively to explore the possible mechanisms.Results:The"target-disease"network diagram predicted by network pharmacology,showed that the potential target of SE involves a variety of CNS diseases,among which depression accounts for the majority.The experimental results showed that SE(1.8,1.35 g/kg)significantly decreased the immobility period,compared with the CUMS group in FST and TST in mice after 3-week treatment,while SE exhibited no significant effect on exploratory behavior in OFT in mice.Compared with CUMS group,the SE group(0.9 g/kg)showed significant differences(P<0.05)in DA levels in the hippocampus and cerebral cortex.In addition,compared with CUMS control group,SE(1.8 g/kg)group showed a significant effect on decreasing the activities of CORT(P<0.05),and serum IL-2level with no statistical significance.Finally,Western blot results showed that compared with the model group,Nrf2,Keap1,NQO1 and HO-1 protein expressions in SE group(1.8 g/kg)were up-regulated(all P<0.01).Conclusion:The SE extract may have an antidepressant effect,which appeared to regulate Nrf2-ARE pathway and increased levels of DA and CORT in the hippocampus and cortex.