The Neuroprotective Effects Of Bet In Brain Tissue Of HHcy Rats And Primary Culture Of Rat Hippocampal Cells

ObjectiveTo observe the neuroprotective effects of Bet in brain tissue of HHcy rats and primaryculture of rat hippocampal cells. In Vivo,Based on the HHcy rat model, we investigated themajor pathological mechanisms of HHcy disease.To explore the effects and mechanisms ofBet preventing HHcy disease and the relationship of plasma total homocysteine (tHcy)level in rats. We detectiving the the activity of SOD, the content of MDA、GSH and nitrieoxide. In Vitro,To study whether Bet could protect the primary rat hippocampal neuronalcells injured by high level of homocysteine;To prove wether Bet could preventhyperhomocysteinemia induced primary rat hippocampal neuronal by detectiving the Bcl-2and Bax protein’s expression、the activity of SOD and the content of MDA.Methods1The neuroprotective effects of Bet in brain tissue of HHcy rats: Feeding healthymale Wistar rats with high methionine diet,Hhcy group (intragastric infusion of1.0mlsaline), Betaine low/medium/high concentration groups (betaine gavage). After thetreatment，the rats were taken caudal blood to detect the serum homocysteine contents. HEstaining was used to observe morphological changes of hippocampus tissue.2The neuroprotective effects of Bet in primary culture of rat hippocampalcells:Protection by Bet was studied at the in vitro level using primary rat hippocampalneuronal cultures exposed to Hcy, a model of Hhcy injury.The cells were treated withHomocysteine (Hcy,16mmol/L) for12h following with betaine treatment for12h,at theconcentrations of12.5,25and50mmol/L for betaine. The cellar viability was detectedusing MTT chromatometry and the apoptosis and necrosis was detected by flow cytometer.Western blotting method were used to detect the Bcl-2and Bax protein’s expressions.Meanwhile, the activity of superoxide dismutase (SOD), lactate dehydrogenase (LDH) andthe content of malondialdehyde (MDA) were detected by appropriate kits. Results1The neuroprotective effects of Bet in brain tissue of HHcy rats:homocysteine levelin Hhcy group was significantly lower than that of the normal group (P<0.01);Comparedwith normal control group,rats in the model group had more apoptotic neurons in thehippocampal CA1、 CA3and DG area,prominent pathological damage,significantlydecreased SOD activities (P<0.01) and significantly increased LDH activity and MDAlevel (P<0.01).Compared with the model group,rats in all the treatment groups haddecreased apoptosis and less ultrastructure damage; and rats in high-dose Bet group hadsignificantly increased SOD activities and significantly decreased LDH and MDA activityin the plasma and brain tissue homogenate (P<0.01).2The neuroprotective effects of Bet in primary culture of rat hippocampal cells:Highlevel of homocysteine could damage the primary cultured hippocampal neurons obviouslyand triggered apoptosis of cells. While in Bet groups, condition of the primary culturedhippocampal neurons is improved. Bet could reduce both the rate of growth inhibition andthe rate of apoptosis significantly, increase Bcl-2protein’s expression and decrease Baxprotein’s expression obviously. Besides, Bet could increase the activity of SOD anddecrease the expression of MDA which showed that Bet could protect the primary culturedhippocampal neurons from oxidation dysfuction by high level of homocysteine.Conclusion1Betaine hydrochloride might protect the hippocampal tissue pathological damage inrats of Hhcy.2Betaine hydrochloride might increase the antioxidant ability in Hhcy rats.Theactivity of SOD and the content of GSH in the in the plasma and brain tissue homogenateof the Hhcy group was significant lower, the content of MDA and NO was significanthigher compared with normal group. Compared with the model group,rats in Bet group hadsignificantly increased SOD activities and significantly decreased MDA and NO activity inthe plasma and brain tissue homogenate.3Bet can protect the primary cultured hippocampal neurons against Hcy-inducedneurotoxicity.4The inhibition of Bet on apoptosis of hippocampal neuron through decrease theexpression of Bax and increasing the expression of Bcl-2.5Bet can protect the primary cultured hippocampal neurons by inereasing the activityof SOD and decreasinge the content of MDA in hippocampal neurons under oxidativedamage.