The Behavior Evaluation Of6-OHDA-induced Parkinson’s Disease Model And The Protective Effect Of Gentiopicrosides On This Model

Parkinson’s disease (PD) is a common neurodegenerative disorderdisease in the aged, which is characterized by progressive loss ofdopamine-producing neurons in the substantia nigra pars compacta andaccordingly low level of dopamine in the nigrostriatal pathway, so it makea lot of pain to the old people and their families. The main clinicalcharacteristics were static tremors, rigidity muscle, slow movement andinstability post. The pathogenesis of PD is complicated but unclear.6-hydroxydopamine (6-OHDA), a hydroxylation ramification of theneurotransmitter dopamine, was the first successfully separated by Senohin1959and can high selectively cause acute collapse of sympatheticadrenergic nerve endings. In1968, the study of Ungerstedt shows that theinjection of6-OHDA to substantia nigra compacta resulted in thesubstantia nigra striatum dopamine system anterograde degeneration,thereby creating the first animal model. This study is using the quantitative6-OHDA injected to the left brain striatum of SD rats to induce Parkinson’sdisease.Gentiopicroside, one of effectively active constituents extracted fromGentiana scabra Bge and Gentiana macrophylla, has been proved to amultiformity of pharmacological activity, including anti-inflammatory,analgesia, hepatic protection, cholagogue, invigorating the stomach andanti-oxidation effects. Our previous studies have found that it can inhibitMPP+induced IkBα degradation in SH SY5Y cells, inhibit theinflammation activation of NF-kB signaling pathway, reduce theexpression of TNF-α, IL-1β, iNOS, and reduce the expression levels of MMP-9induced by the inflammation stimulates cells. As suggested toneuroinflammation as targets, gentiopicroside have potential value in theprevention and treatment of PD. However, the neuroprotective effect ofgentiopicroside on animal model of Parkinson’s disease is not reported.To extract and purify gentiopicroside from radix gentianaemacrophyllae; to build behavior evaluation system of6-OHDA inducedParkinson’s disease model, and to provide scientific evaluation methods fordrug treatment of the disease; and to study the neuroprotective effect ofgentiopicroside on6-OHDA induced Parkinson’s disease.Firstly, using the SP70macroporous resin and silica gel purificationmethod to separate and purificate the gentiopicroside from the RadixGentianae Macrophyllae water extract. Quantitative6-OHDA was injectedsolution to the left brain striatum to induce PD model. After3weeks,rotation behavior of the animals were observed(≥7r/min, as buildingsuccess) after intraperitoneal injection of the APO(Apomorphine).Respectively, Applied rolling-bar and open-field experiment to measureand analyse the animals motor function before and after administration ofgentiopicroside. The EMG experiment was applied to measure tremoramplitude of rats. The protective effect of gentiopicroside was measuredafter administrated successively for2weeks.The expression of tyrosinehydroxylase in rat substantia nigra of on the left side brain was detected byimmunohistochemistry.The experiment method of gentianae macrophyllae gentian extractionfrom radix glycosides is more feasible and innovative than the previousextraction technology. Gentiopicroside is purified by HPLC as thegentiopicroside standard. After quantitative injection6-OHDA to left brainstriatum, apomorphine was intraperitoneally injected to induce rotation.The slewing ring number was increased significantly, which suggestedmodel was induced successfully; In the rolling-bar test, the time of the ratson the rotating rod was significantly shortened; in the open-field experiments, thenumber of horizontally across was decreased,indicating motor dysfunction;EMG tests showed the muscle vibration frequency and amplitude of somerat were increased. According to the results above, we classificate the typeof Parkinson’s disease: tremor, movement disorders, and hybrid. Afterquantitative injection6-OHDA to left brain striatum, intraperitonealinjection apomorphine to induce rotation, the behavior tests of the modelgroup were respectively significantly different from the sham group. Aftersuccessively administrated of gentiopicroside for2weeks, the number ofrotation in30min of the high-dose group and positive medicine group issignificantly less than the model group, prolonged in the time on therotating rod, reducing amplitude of the involuntary tremors, there weresignificant differences compared with model group. Gentiopicroside ofhigh-dose and Madopar group could obviously improve the morphology ofTH immune positive neurons, and increase the number of TH positive cells.Gentiopicroside high dose group and positive medicine group canobviously improve the morphology of TH immune positive neurons, andincrease the number of TH positive cells.The experiment method of gentianae macrophyllae gentian extractionfrom radix glycosides is more feasible and innovative than the previousextraction technology. Classification of the6-OHDA-induced Parkinson’sdisease rat model according to the behavior test results is bettercharacterized motor function and symptoms of Parkinson’s disease, whichis useful for the drug development of the disease. The motor dysfunction,muscle fatigue and involuntary tremors of Parkinson’s disease have beenimproved by gentiopicroside group. Gentiopicroside of300mg/kg couldsignificantly improve the amplitude and the model, indicating that thetherapeutic effect of gentiopicroside on involuntary tremors of Parkinson’sdisease is more obvious than the effects on other behavior. Gentiopicrosidesignificantly increased the number of TH positive cells, suggesting it may effect on nigrostriatal pathway in Parkinson’s disease.