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OBJECTIVE To investigate the improvement effects of Arisaema Cum Bile on Parkinson’s disease （PD） model mice and its potential mechanism. METHODS Sixty male C57BL/6J mice were randomly divided into normal group， model group， Arisaema Cum Bile low-dose group [0.39 g/（kg·d）]， Arisaema Cum Bile high-dose group [1.56 g/（kg·d）] and positive control drug Levodopa tablet group [80 mg/（kg·d）]， with 12 mice in each group. Except that normal group was given constant volume of normal saline， other groups were given 1-methyl-4-phenyl-1，2，3，6-tetrahydropyridine [MPTP，35 mg/（kg·d）] intraperitoneally for 5 consecutive days to induce subacute PD model； after modeling， they were given relevant medicine continuously for 7 d； rod climbing test and line suspension test were performed 1 d before modeling， on the 5th day of modeling and after the last medication. The number of tyrosine hydroxylase （TH）-positive neurons in the substantia nigra of mice were measured by immunofluorescence； the levels of interleukin 1β （IL-1β） and tumor necrosis factor α（ TNF-α） in serum and the levels of IL- E-mail：qhwang668@sina.com 1β， TNF-α， cyclooxygenase-2 （COX-2） and inducible nitric oxide synthase （iNOS） in the substantia nigra of mice were measured by enzyme-linked immunosorbent assay. The expression levels of cAMP-dependent protein kinase catalytic subunit α （PKA C-α）， glutathione peroxidase 4 （GPX4） and ferritin heavy chain polypeptide 1 （FTH1） proteins in the substantia nigra of mice was measured by Western blot. RESULTS After last medicine， compared with the normal group， mice in the model group had significantly longer pole-climbing time （P＜0.01）， significantly lower line suspension scores （P＜0.01）， significantly fewer TH-positive neurons in the substantia nigra （P＜0.01）， significantly higher serum concentrations of IL-1β and TNF-α and nigrostriatal concentrations of IL-1β， TNF-α， COX-2 and iNOS （P＜0.01）， while lower protein expression levels of GPX4， PKA C-α and FTH1 in the substantia nigra （P＜0.05 or P＜0.01）. Compared with the model group， the above indexes of mice were significantly returned in Arisaema Cum Bile high-dose group （P＜0.05 or P＜ 0.01）. CONCLUSIONS Arisaema Cum Bile can improve motor impairment and reduce apoptosis of nigrostriatal TH neurons in MPTP-induced PD mice， and has neuroprotective effects on model mice； this may be related to its inhibition of neuroinflammation and the inhibition of ferroptosis by up-regulating PKA signaling pathway.
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ObjectiveTo investigate the protective effect and mechanism of Achyranthis Bidentatae Radix-Paeoniae Radix Alba on dopaminergic neurons in Parkinson's disease mouse model with the syndrome of ascendant hyperactivity of liver Yang. MethodThe C57BL/6 mice were randomly assigned into normal group， a model group， low-， medium， and high-dose （3.25， 6.5， 13 g·kg-1） Achyranthis Bidentatae Radix-Paeoniae Radix Alba groups， and a selegiline group （0.01 g·kg-1）. The mouse model of Parkinson's disease with the syndrome of ascendant hyperactivity of liver yang was established by intragastric administration of Fuzitang combined with intraperitoneal injection of 1-methyl-4-phenyl-1，2，3，6-tetrahydropyridine （MPTP）. The behavioral changes were evaluated by rotarod test and pole test. The protein levels of Ras homolog gene family member A （RhoA）， Rho-associated coiled-coil containing protein kinase 2 （ROCK2）， myosin light chain 1 （MLC1）， and α-synuclein in the substantia nigra were determined by Western blot. Real-time fluorescence quantitative PCR （Real-time PCR） was employed to determine the mRNA levels of RhoA， ROCK2， and MLC1 in the substantia nigra. Enzyme-linked immunosorbent assay （ELISA） was used to measure the levels of tumor necrosis factor-α （TNF-α） and interleukin-1β （IL-1β）. The ultrastructural changes of mouse neurons were observed under a transmission electron microscope. ResultCompared with the normal group， the modeling shortened the latency to fall， increased the average total time in the pole test （P<0.01）， and up-regulated the levels of RhoA， ROCK2， MLC1， TNF-α， α-synuclein， and IL-1β in the substantia nigra （P<0.05）. Compared with the model group， different doses of Achyranthis Bidentatae Radix-Paeoniae Radix Alba and selegiline prolonged the latency to fall， shortened the average total time in the pole test （P<0.05， P<0.01）， and down-regulated the levels of ROCK2， MLC1， α-synuclein， TNF-α， and IL-1β in a dose-dependent manner （P<0.05）. Further， the modeling decreased the number of cytoplasmic organelles and caused mitochondrial swelling and abnormal shape of endoplasmic reticulum compared with the normal group. The neurons in high-dose Achyranthis Bidentatae Radix-Paeoniae Radix Alba and selegiline groups showed intact nuclei， clear cell boundary， and normal endoplasmic reticulum shape. ConclusionThe combination of Achyranthis Bidentatae Radix and Paeoniae Radix Alba may improve the motor coordination ability of Parkinson's disease mouse model with the syndrome of ascendant hyperactivity of liver yang by inhibiting the neuroinflammation mediated by the RhoA/ROCK2 signaling pathway in the brain.
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OBJECTIVE： To observe neuroprotective effects of low-molecular-weight chondroitin sulfate （CS） on dopaminergic neurons in Parkinson’s disease （PD） mice model induced by 1-methyl-4-phenyl-1，2，3，6-tetrahydropyridine （MPTP）. METHODS： C57BL/6 mice were randomly divided into control group， MPTP injury group， low-molecular-weight CS low-dose and high-dose groups （100， 400 mg/kg）. Control group and MPTP injury group were given constant volume of normal saline intragstrically， administration groups were given relevant medicine intragastrically， once a day， for consecutive 17 d. Since 11th day after medication， except for control group， other groups were given MPTP solution （20 mg/kg） intraperitoneally to induce PD model， once a day， consecutive 5 d. After last medication， behavioral changes of mice （10 mice in each group） were evaluated by rotary rod fatigue tester. The damage of dopamine neurons （the percentage of TH positive cell and the percentage of fluorescence intensity） in substantia nigra of mice （3 mice in each group） was detected by immunohistochemistry and immunofluorescence. The content of dopamine in striatum was determined by HPLC （6 mice in each group）. The changes of oxidant stress indexes （SOD， GSH-Px， MDA） in substantia nigra of mice were determined by chemical colorimetry （6 mice in each group）. RESULTS： Compared with control group， retention time of mice on rotating rods was shortened significantly in MPTP injury group； TH positive cells of substantia nigra were decreased significantly， fluorescence intensity was obviously weakened； the percentage of positive cells and fluorescence intensity， the content of dopamine in striatum， the activities of SOD and GSH-Px in substantia nigra were decreased significantly， while the content of MDA was increased significantly （P＜0.01）. Compared with MPTP injury group， retention time of mice on the rotating rods was prolonged significantly in low-molecular-weight CS groups， the number of TH positive cells was increased significantly in substantia nigra and fluorescence intensity was increased significantly； the percentage of positive cells， the percentage of fluorescence intensity and the content of dopamine in striatum were increased significantly， while above indexes of high-dose group were significantly longer or higher than those of low-dose group （P＜0.05 or P＜0.01）. The activities of SOD and GSH-Px in substantia nigra were increased significantly in low-molecular-weight CS groups， while the content of MDA in substantia nigra was decreased significantly in low-molecular-weight CS high-dose group （P＜0.05 or P＜0.01）. CONCLUSIONS： Prophylactic administration of low-molecular-weight CS can relieve the damage of dopaminergic neurons in substantia nigra of PD model mice induced by MPTP in a dose-dependent manner， and increase the secretion of dopamine in striatum. The effect may be related to the inhibition of lipid peroxidation and the enhancement of antioxidant capacity of tissues.
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AIM:To investigate the effects of cordycepin on the motor and cognition in Parkinson disease mice induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP).METHODS:C57BL/6 mice were intraperitoneally injected with MPTP at a dose of 30 mg/kg daily for consecutive 8 d to establish the model of Parkinson disease.HE staining was used to observe the cell number in the substantia nigra pars compacta (SNpc) from the mice.Western blot was used to detect the protein level of tyrosine hydroxylase (TH) in substantia nigra (SN).The effects of cordycepin on the motor, emotional change and cognitive behavior of the Parkinson disease mice were examined by open-field test (OFT) , spontaneous alternating behavior (SAB) and water maze test (WMT) , respectively.RESULTS:Cordycepin significantly reduced the apoptosis of cells in SNpc and reversed the decrease in the expression of TH in SN induced by MPTP (P<0.05).Furthermore, cordycepin was able to improve the average speed in OFT (P<0.05) , and increased the total number of arm entry and the accuracy in SAB (P<0.05) , but had no obvious effect on the latency in WMT.CONCLU-SION:Cordycepin is capable of attenuating the impairments of motor and explorative ability in the early stage of Parkinson disease mice, but does not alter the cognitive dysfunction.
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Objective To investigate the protective effects of stilbene glycoside(2,3,5,4'-tetrahydroxy-stilbene-2-O-β-D-glucoside,TSG) on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mice model of Parkinson's disease(PD).Methods Mice were randomly divided into the blank control group,the negative control group,the TSG high-dose group,the TSG low-dose group and the positive drug group(n=20 each).Mice were weighted daily to observe the changes of body weight,and mice motor and behavior function were tested by open field test.Level changes of α/β synuclein in brain cortex,cerebellum,midbrain,and hippocampal were detected by Western blot.Results Compared with the blank control group,the negative control group showed that the body weight was decreased (P ＜ 0.05).Compared with the negative control group,the body weight was increased in the TSG high-and low-dose groups and the positive drug group (P ＜ 0.05).The spontaneous behavior was impaired in the negative control group.Compared with the blank control group,the negative control group showed that the open field test showed traveled distance over a 10-min period was significantly shortened at 1 st,7th,28th days after testing(all P＜0.05).The trajectory of motor axons indicated that mice in the negative control group showed dyskinesia,but the groups of positive drug and high-and low-dose of TSG could reverse this dyskinesia.Compared with the blank control group,brain α/β synuclein protein levels were increased in the negative control group,and decreased in positive drug and TSG high-and low-dose groups (P ＜0.05).Conclusions Stilbene glycosides exert neuroprotective effects in MPTP-induced mice model of PD.
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ABSTRACT This study aims to explore the relationship between the anxious symptoms and the impairment of 5-hydroxytryptamine system in PD mice induced by different dosages of MPTP. The mice from the three model groups, the low-dose, dose and high-dose group, took longer time in the dark box than those in the control group (P<0.05). However, no statistically significant differences were found among the model groups. The number of open arm entry (OE) and the open arm time (OT) were significant lower in the model group than those in the control group in the elevated plus-maze test (P＜0.05). The percentage of OE in modle group was significantly lower compared with the control group (P＜0.05). The concentrations of striatum DA, HVA, 5-HT, and 5-HIAA were significantly reduced in the three model groups compared to the control group (P＜0.05). The 5-HT concentrations of high-dose group was significantly lower than those of the control group in the prefrontal cortex (P＜0.05). Anxiety symptoms were appeared in the three model groups of early PD mice, but no difference existed among these groups. The 5-hydroxytryptamine system was damaged after MPTP injection, which could lead to anxiety. However, the impairment of 5-hydroxytryptamine system induced by MPTP was dose-independent.
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Objective To investigate the effect and mechanism of interfering the nicotinamide mononucleotide adenylyltransferase 1(NMNAT1)gene in Parkinson's disease(PD)mouse models. Methods Thirty mice were randomly assigned to three groups: the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)group, the small interfering nicotinamide mononucleotide adenylyltransferase 1 (siNMNAT1)+MPTP group, and the control group, with 10 mice in each group.After injecting siRNA-green fluorescent protein(GFP)lentivirals directly into substantia nigra(SN),mice received intraperitoneal injections of MPTP, which was the siNMNAT1 +MPTP group.While the MPTP group was only with injections of MPTP,and the control group was with neither siRNA nor MPTP.Then we assessed the motor coordination ability firstly.To observe the variation of nigrostriatal pathway, the counts of dopamanergic neurons in SN were measured by tyrosine hydroxylase(TH)immunofluorescence staining.And the expression of TH in striatum, which was used to estimate the dopaminergic neurons axonal variation, was analyzed by RT-PCR.Then the expression of TH, SOD1, Bcl2, Bax, Bcl2/Bax in SN was estimated through Western blotting.Results Compared with the control group,the siNMNAT1+MPTP group and the MPTP group decreased significantly in motor coordination ability(creep down time: siNMNAT1 +MPTP group(62.8 ±15.7)s,MPTP group(77.9 ±13.5)s, control group(122.0 ±25.2)s), dopamanergic neuron counts(siNMNAT1 +MPTP group 45.0 ±6.7, MPTP group 68.0 ±11.3, control group 93.0 ± 12.8)and the striatal TH expression(Creep down time: t=-6.291, P=0.000; t=-4.865, P=0.000.Dopamanergic neuron counts:t=-10.482,P=0.000;t=-4.624, P=0.000.TH expression:t=-9.117,P=0.000;t=-5.716, P=0.000).Although the siNMNAT1+MPTP group showed lower coordination ability than the MPTP group, there was no statistically significant difference.Whereas the counts of dopamanergic neurons in SN(t=-5.487, P=0.000), the expression of TH in striatum(t=-5.146,P=0.003),SOD1(t=-4.143, P=0.001)and Bcl2/Bax(t=-6.303, P=0.000)were obviously decreased in the siNMNAT1+MPTP group,in which Bax increased significantly(t=3.550,P=0.002).Conclusions Interfering the expression of NMNAT1 aggravated the neurodegeneration in PD, and the mechanism might be related to oxidative stress and programmed cell death.
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Objective To explore the feasibility of establishing a tree shrew model of chronic gastrointestinal mucosal injury. Methods A total of 12 adult male tree shrews were randomly divided into 3 groups. The experimental groups 1 and 2 were administered with intraperitoneal injection of 2 mg/(kg·d)and 1 mg/(kg·d)of 1-methyl-4-phenyl-1,2, 3,6-tetrahydropyridine(MPTP)once every day for 56 days, respectively. The control group was given the same volume of sterile saline at the corresponding time points. Changes in the body weight of the tree shrews were observed. The contents of dopamine in the cerebrospinal fluid were detected. Gastrointestinal morphology was observed by stereoscope and histopathological changes of the gastrointestinal mucosa were examined by HE staining. Results The body weight and the contents of dopamine in the cerebrospinal fluid of the tree shrews in the model group were significantly decreased(P< 0.05 for both). Pathological changes to some extent of the gastric antrum, the gastric body and the duodenum were observed, without obvious differences between the 2 mg/kg group and the 1 mg/kg group. No obvious changes were found in the control group. Conclusions Long-term intraperitoneal injection with a low dose of MPTP is a feasible method for the establishment of a tree shrew model of chronic gastrointestinal mucosal injury. The optimal dose is 2 mg/(kg·d)every day for 56 days.
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OBJECTIVE To evaluate these activities of Rg1 in the 1-methyl-4-phenyl-1,2,3,6-tetrahy?dropyridine (MPTP)/probenecid (MPTP/p)-induced PD mouse model for the first time and to elucidate the underlying mechanisms. METHODS Male C57BL/6 mice were randomly assigned to six groups. One hour prior to MPTP/p injection, Group Ⅲ-Ⅵ mice received 10 mg·kg-1, 20 mg·kg-1, or 40 mg·kg-1 Rg1 or 3 mg·kg-1 selegiline, respectively, orally from D (-3) to D49. Group Ⅰ-Ⅱ mice received solvent water. Subsequently, GroupⅡ-Ⅵ mice received by injection MPTP-HCl (25 mg·kg- 1 bw dissolved in 0.9% saline, sc) on a 40-d schedule at intervals of 4 d between consecutive doses in combination with an adjuvant drug, probenecid (250 mg·kg- 1 bw in 0.03 mL of DMSO, ip); GroupⅠ mice were injected with saline and probenecid. Behavioral performance was assessed in the open field test, pole test and rotarod test. Neurotransmitters in the striatum were detected using HPLC. Protein levels were measured by Western blot. Pathological characteristics were examined by immunohistochemistry. Ultrastructure changes were observed by electron microscopy. RESULTS Oral treatment with Rg1 significantly attenuated the high MPTP-induced mortality, behavior defects, loss of dopamine neurons and abnormal ultrastructure changes in the SNpc. Other assays indicated that the protective effect of Rg1 may be mediated by its anti-neuroinflammatory properties. Rg1 regulated MPTP-induced reactive astrocytes and microglia and decreased the release of cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-1b (IL-1b) in the SNpc. Rg1 also alleviated the unusual MPTP induced increase in oligomeric, phosphorylated and disease-related a-synuclein in the SNpc. CONCLUSION Rg1 protects dopaminergic neurons, most likely by reducing aberrant a-synuclein-mediated neuroinflammation, and holds promise for Parkinson disease therapeutics.
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Objective To investigate the expression of mitochondrial transcription termination factors (MTERFs) in various tissues and cells, and the changes of MTERFs induced by l-methyl-4-phenyl-l, 2, 3, 6-tetrahydropyridine (MPTP)/l-methyl-4-pheny lpyridine (MPP+). Methods Western blotting was used to measure the expression of the MTERFs in brain, liver, kidney of C57BL mice and in human SH-SY5Y, HCM, L-02 cells. MPTP/MPP+ was injected to imitate PD animal/cell models. The changes of MTERFs protein were detected through western blotting. Results The expression of MTERFs was higher in mice brain and SH-SY5Y cells. In PD mouse model induced by MPTP, MTERF3 reduced significantly. Conclusion The expression of MTERFs was higher in mouse brain and SH-SY5Y cells. After induced by MPTP/MPP+, MTERF3 decreased obviously, which increased transcription level and might involve in a process of Parkinsons disease.
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@#This study aimed at investigating the neuroprotective effect and behavior improvement of rasagiline on 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine(MPTP)model mice of Parkinson′s disease. The tyrosine hydroxylase(TH)-positive dopaminergic neurons in substantia nigra were observed by immunocytochemistry. HPLC-ECD was used to detect the dopamine and its metabolite levels. Western blot was used to examine the protein expression of TH. The results showed that the mice appeared a series of acute behavior change after the injection of MPTP. Rasagiline(20 mg/kg)exerted significant protection against MPTP-induced loss of TH-positive dopaminergic neurons. The TH-positive neurons in rasagiline-treated mice brain increased significantly compared with those of MPTP-treated group. Rasagiline also enhanced dopamine and its metabolite levels in striatum significantly. In conclusion, rasagiline has protective effect on the acute mouse model of MPTP-induced Parkinsonism.
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Objective To investigate the anxious behavior in acute parkinson's mice that were induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) injection.Methods Twenty mice were randomly divided into the control group (n =10) and model group(n =10);The model group was induced by injecting MPTP dosage,and the control group was induced by the same dose of saline.The anxious behaviors in mice were tested by the elevated plus-maze test and the light/dark box.Results The model group mice spent a longer time than the control group in the dark box (P ＜ 0.05).The open arm entry (OE),open arm time (OT) and OE％ of model group was significantly less than that in control group in the elevated plus-maze test (P ＜ 0.01),the OT％ was significantly less than control group (P ＜0.05).Conclusions Anxiety symptoms appeared in the model group of early parkinson disease (PD)mice.
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Stem cell technologies are particularly attractive in Parkinson's disease (PD) research although they occasionally need long-term treatment for anti-parkinsonian activity. Unfortunately, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) widely used as a model for PD has several limitations, including the risk of dose-dependent mortality and the difficulty of maintenance of PD symptoms during the whole experiment period. Therefore, we tested if our novel MPTP regimen protocol (2 mg/kg for 2 consecutive days and 1 mg/kg for next 3 consecutive days) can be maintained stable parkinsonism without mortality for long-term stem cell therapy. For this, we used small-bodied common marmoset monkeys (Callithrix jacchus) among several nonhuman primates showing high anatomical, functional, and behavioral similarities to humans. Along with no mortality, the behavioral changes involved in PD symptoms were maintained for 32 weeks. Also, the loss of jumping ability of the MPTP-treated marmosets in the Tower test was not recovered by 32 weeks. Positron emission tomography (PET) analysis revealed that remarkable decreases of bindings of ¹⁸F-FP-CIT were observed at the striatum of the brains of the marmosets received MPTP during the full period of the experiment for 32 weeks. In the substantia nigra of the marmosets, the loss of tyrosine hydroxylase (TH) immunoreactivity was also observed at 32 weeks following the MPTP treatment. In conclusion, our low-dose MPTP regimen protocol was found to be stable parkinsonism without mortality as evidenced by behavior, PET, and TH immunohistochemistry. This result will be useful for evaluation of possible long-term stem cell therapy for anti-parkinsonian activity.
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Humans , 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine , Brain , Callithrix , Haplorhini , Immunohistochemistry , Models, Animal , Mortality , Parkinson Disease , Parkinsonian Disorders , Positron-Emission Tomography , Primates , Stem Cells , Substantia Nigra , Tyrosine 3-MonooxygenaseABSTRACT
Objective To explore the localization and expression of dopaminergic neurons in olfactory bulb of cynomolgus monkeys damaged by 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP).Methods Three adult cynomolgus monkeys were injected with MPTP to induce the damage of dopamine neurons ( MPTP group ) and three adult cynomolgus monkeys were as a control group .Immunohistochemical staining was performed to examine the localization and expression of dopaminergic neurons in the olfactory bulb in normal and MPTP group monkeys .The numbers of DA-positive and DARPP32-positive cells were counted and the average absorbance was measured in normal and MPTP group .Results DA and DARPP32 positive neurons were concentrated in the glomerular layer ( GL) of olfactory bulb.DA positive nerve fibers were distributed in the GL while DARPP 32 positive nerve fibers appeared in all layers , and most nerve fibers were in GL and external plexiform layers (EPL).After MPTP injury, compared with the normal control group , DA and DARPP32 positive neurons and nerve fibers decreased in MPTP group and DA neurons and nerve fibers decreased significantly . Conclusions DA neurons and nerve fibers are in the GL of cynomolgus monkey olfactory bulb .DA neurons and fibers are significantly reduced in the olfactory bulb of cynomolgus monkeys damaged by MPTP , which may be associated with the dysosmia in Parkinson ’ s disease .
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Destruction of dopaminergic neurons in the substantia nigra pars compacta (SNpc) is a common pathophysiology of Parkinson's disease (PD). Characteristics of PD patients include bradykinesia, muscle rigidity, tremor at rest and disturbances in balance. For about four decades, PD animal models have been produced by toxin-induced or gene-modified techniques. However, in mice, none of the gene-modified models showed all 4 major criteria of PD. Moreover, distinguishing between PD model pigs and normal pigs has not been well established. Therefore, we planned to produce a pig model for PD by chronic subcutaneous administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), neurotoxin. Changes in behavioral patterns of pigs were thoroughly evaluated and a new motor scoring system was established for this porcine model that was based on the Unified Parkinson's Disease Rating Scale (UPDRS) in human PD patients. In summary, this motor scoring system could be helpful to analyze the porcine PD model and to confirm the pathology prior to further examinations, such as positron emission tomography-computed tomography (PET-CT), which is expensive, and invasive immunohistochemistry (IHC) of the brain.
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Animals , Humans , Mice , 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine , Brain , Dopaminergic Neurons , Electrons , Hypokinesia , Immunohistochemistry , Injections, Subcutaneous , Models, Animal , Muscle Rigidity , Parkinson Disease , Pathology , Substantia Nigra , Swine , TremorABSTRACT
INTRODUÇÃO: Modelos experimentais da Doença de Parkinson (DP) que reproduzem a desnervação dopaminérgica têm sido desenvolvidos para estudar a patofisiologia desta doença e analisar a eficácia de novas terapêuticas. Dentre os sinais cardinais da DP temos a rigidez muscular, estudos sugerem que mudanças intrínsecas nas propriedades mecânicas do músculo podem ser responsáveis pelo aumento dessa alteração tônica. OBJETIVO: Analisar a morfologia geral e a histomorfometria do músculo sóleo de ratos Wistar induzidos ao Parkinsonismo por 1-metil-4-fenil-1,2,3,6-tetrahidropiridina (MPTP). MATERIAIS E MÉTODOS: Utilizaram-se 24 ratos Wistar machos, com idade de 13 semanas e peso de 279 ± 13 g, divididos em quatro grupos: 1- controle-controle (n = 6): sham tratados com benserazida + salina; 2 - controle-L-DOPA (n = 6): sham tratados com benserazida + L-DOPA; 3 - MPTP- controle (n = 6): lesão na substância negra (SNc) por MPTP tratados com benserazida + salina; 4 - MPTP-L-DOPA (n = 6): lesão na SNc por MPTP tratados com benserazida + L-DOPA. Esses animais foram submetidos a eutanásia 35 dias após os procedimentos experimentais. Foram analisados: peso corporal, peso muscular, morfologia geral do músculo com microscopia de luz e mensuração da área de secção transversa das fibras musculares. Realizaram-se comparações com o teste t pareado entre o peso corporal inicial e final. A ANOVA post-hoc Tukey foi usada para comparações entre os grupos, sendo considerado significativo p ≤ 0,05. RESULTADOS: Não foram encontradas diferenças estatisticamente significativas nas variáveis analisadas. CONCLUSÃO: Os dados analisados não excluem a possibilidade de alterações ocorrerem no interior dessas células, nos tipos de fibras musculares ou em longo prazo.
INTRODUCTION: Animal models for Parkinson's disease (PD) which mimetize dopaminergic degeneration of nervous cells have been developed to study the pathology of this disease and to analyze the efficiency of new therapies. One of the cardinal signs of PD have muscle stiffness, studies suggest that intrinsic changes in mechanical properties of muscle may be responsible for the increase of this amendment tonic. OBJECTIVE: To analyze the morphology and histomorphometry of soleus muscle of rats PD-induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropiridine (MPTP). MATERIALS AND METHODS: We used 24 male Wistar rats, with the age of 13 weeks and 279 ± 13 g weight, divided into four groups: 1- control-control (n = 6): sham treated with benserazidasalina; 2 - control-L-DOPA (n = 6): sham treated with benserazida + L-DOPA; 3 - MPTP-control (n = 6): injury in substantia nigra (SNc) by MPTP treated with benserazidasalina; 4 - MPTP-L-DOPA (n = 6): CNS injury by MPTP treated with benserazida + L-DOPA. These animals were euthanized 35 days after the experimental procedures. It was analyzed: body weight, muscle weight, General muscle morphology with light microscopy and measurement of the cross-sectional area of muscle fibers. Comparisons between initial and final body weight were developed with the paired T-test. The Tukey post-hoc ANOVA was used for comparisons between groups, being considered significant p ≤ 0.05. RESULTS: No statistically significant differences were found in the analyzed variables. CONCLUSION: The data analyzed do not exclude the possibility of occurrence of changes in the interior of these cells, in the types of muscle fibers or long term.
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Animals , Muscle Rigidity , Parkinson Disease , Muscle, Skeletal , Physical Therapy ModalitiesABSTRACT
Objective To investigate any neuroprotective effect of hyperbaric oxygenation (HBO) on the mitochondria of dopaminergic neurons using a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of Parkinson's disease.Methods Forty-eight male SPF C57BL/6 mice were randomly assigned to either a normal control group (treated with a 30 ml/kg intraperitoneal injection of physiological saline once a day),a model group ( treated with a 30 mg/kg intraperitoneal injection of MPTP once a day) or an HBO therapy group ( treated with a 30 mg/kg intraperitoneal injection of MPTP and HBO once a day).The expression of tyrosine hydroxylase (TH) protein,PINK1 protein and caspase-3 in brain tissue was measured using immunohistochemistry and Western blotting assays.Results Compared with the control group,the expression levels of TH protein and PINK1 protein were significantly lower in the neurons of the substantia nigra in the model mice.HBO therapy upregulated the expression of TH and PINK1 protein.Compared with the control group,the average level of caspase-3 protein in the neurons of the substantia nigra in the model mice was significantly higher.HBO therapy downregulates the expression of caspase-3 protein.Conclusions HBO can protect mitochondria and inhibit apoptosis of dopaminergic neurons in the substantia nigra of brains with (MPTP-induced) Parkinson's disease by upregulating the expression of PINK1 protein and TH protein,and downregulating the expression of caspase-3 protein.
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Objective To observe the effects of enriched environmen(EE) on brain-derived neurotrophic factor (BDNF) in substantia nigra (SN) of senescence-accelerated prone mice, so as to explore the possible mechanism of EE in alleviating MPTP-induced damage and in protecting dopaminergic neurons in the SN. Methods Totally 80 3-month old female SAMP8 mice were averagely assigned to EE and standard environment (SE) groups at random. After three months, the mice in each group were further divided into 2 subgroups at random, MPTP group and NS group (n = 20). The MPTP groups received subcutaneous injection of MPTP, and the NS mice were treated with an equal volume of NS. At the seventh day, the mice were sacrificed for RT-PCR and immunohistochemistry staining. RT-PCR was used to examine BDNF mRNA expression and immunohistochemistry staining was used to examine BDNF-ir expression. Results Compared with SE+NS mice, EE+NS mice had significantly increased BDNF mRNA expression(P<0.01), and the number of BDNF-ir cell and COD values in SN were also significantly increased (P<0.01). Compared with SE+NS mice, SE+MPTP mice showed significantly decreased BDNF mRNA expression (P<0.001) , and the number of BDNF-ir cells and the COD values in SN of mice were significantly decreased (P<0.01). Compared with SE+MPTP mice, EE+MPTP mice showed increased BDNF mRNA expression (P<0.01), and the number of BDNF-ir cells and the COD values in SN were significantly increased (P<0.01). Conclusion EE can increase BDNF mRNA expression and BDNF-ir cell number in SN of SAMP8 mice, alleviating MPTP-induced SN damage.
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Objective To compare the difference of spatial reference memory and dopamine (DA) level in the brain between acute,subacute and chronic mouse model of Parkinson' s disease(PD) induced by 1-methyl-4-phenyl-1 ,2,3,6-tetrahydropyridine(MPTP) injection. Methods The acute,subacute and chronic mouse model of Parkinson' s disease were induced by injecting the same MPTP volume dose with different schedules. The spatial reference memory of mice was tested by morris water maze. Dopamine concentration in striatum, hippocampus and the prefrontal cortex were detected with HPLC. The number of tyrosine hydroxylase(TH)-positive cells in the substantia nigra of mice was detected by immunohistochemistry. Results The mean escape latency of the chronic but not the acute or subacute mouse model of Parkinson' s disease was significant longer ( P ＜ 0.05 ) than its control group. The striatum DA concentration of three test groups ( ( 1180. 1 ± 293.0 ) ng/ml, ( 1177.4 ± 450.5 ) ng/ml,( 1149.6 ± 353.0 ) ng/ml ) reduced significantly compared to their control groups ( ( 225.6 ± 79.7 ) ng/ml, ( 273.6± 64.9 ) ng/ml, ( 327. 1 ± 126.2 ) ng/ml, P ＜ 0.01 ). The prefrontal cortex DA concentration of the acute mouse model of Parkinson' s disease ( ( 65.3 ± 23.9 ) ng/ml ) was significant lower than its control group ( ( 41.2 ±18.8 )ng/ml, P ＜ 0.05 ). No significant changes of hippocampus DA concentration were seen between these test groups and their control groups. The number of TH positive cells in substantia nigra significantly decreased in three test groups compared to their control groups( P ＜ 0.05 ). Conclusion The difference of spatial reference memory between three regimens of the mouse model of Parkinson' s disease may not due to the difference of DA level in their brain.
ABSTRACT
There is a great concern in the literature for the development of neuroprotectant drugs to treat Parkinson's disease. Since anesthetic drugs have hyperpolarizing properties, they can possibly act as neuroprotectants. In the present study, we have investigated the neuroprotective effect of a mixture of ketamine (85 mg/kg) and xylazine (3 mg/kg) (K/X) on the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or 6-hydroxydopamine (6-OHDA) rat models of Parkinson's disease. The bilateral infusion of MPTP (100 æg/side) or 6-OHDA (10 æg/side) into the substantia nigra pars compacta of adult male Wistar rats under thiopental anesthesia caused a modest (~67 percent) or severe (~91 percent) loss of tyrosine hydroxylase-immunostained cells, respectively. On the other hand, an apparent neuroprotective effect was observed when the rats were anesthetized with K/X, infused 5 min before surgery. This treatment caused loss of only 33 percent of the nigral tyrosine hydroxylase-immunostained cells due to the MPTP infusion and 51 percent due to the 6-OHDA infusion. This neuroprotective effect of K/X was also suggested by a less severe reduction of striatal dopamine levels in animals treated with these neurotoxins. In the working memory version of the Morris water maze task, both MPTP- and 6-OHDA-lesioned animals spent nearly 10 s longer to find the hidden platform in the groups where the neurotoxins were infused under thiopental anesthesia, compared to control animals. This amnestic effect was not observed in rats infused with the neurotoxins under K/X anesthesia. These results suggest that drugs with a pharmacological profile similar to that of K/X may be useful to delay the progression of Parkinson's disease.