ABSTRACT
Objective To explore the effects of luteolin on cognition function in pentylenetetrazol (PTZ)-induced epileptic rats and related mechanism.Methods Fifty male SD rats were randomly divided into a normal control group(n=8), a model group(n=12), and groups of 25, 50 mg/kg luteolin(both ofn=11), as well as 100 mg/kg luteolin group(n=8). Those rats were given different doses of luteolin (25, 50 and 100 mg/kg, daily, intragastric administration) for 36 consecutive days. Similarly, rats of the normal control group and the model group were given 0.5% sodium carboxymethyl cellulose suspension liquid via intragastric administration. Thirty minutes later, a model of epilepsy was induced using PTZ (40 mg/kg, daily) via intraperitoneal injection except the control group. Learning and memory of rats were evaluated by Morris water maze and novel objective recognition trials(including escape latency and recognition index). The levels of CaM and CaMPK were determined by ELISA methods, and expression of Ras proteins in the hippocampus were detected by Western Blot.Results Compared with the model group, luteolin treatment groups significantly shorten the escape latency(28.51 ± 3.84 s, 19.77 ± 5.41 s, 14.86 ± 2.76 svs. 37.08 ± 5.18 s) in the Morris water maze, and increased recognition index(18.77% ± 2.02%, 25.06% ± 4.32%, 31.92% ± 2.65%vs. 13.87% ± 2.14%) in the novel objection trial(P<0.05 orP<0.01). Meanwhile, CaM(140.33 ± 13.52 ng/L, 124.26 ± 9.97 ng/L, 113.52 ± 11.57 ng/Lvs. 158.36 ± 10.68 ng/L) and CaMPK(8.25 ± 1.37 ng/ml, 7.69 ± 0.84 ng/ml, 6.74 ± 0.93 ng/mlvs. 9.87 ± 1.02 ng/ml) were significantly decreased(P<0.05 orP<0.01). What’s more, the expression of Ras proteins(0.99 ± 0.08, 0.76 ± 0.07, 0.52 ± 0.07vs. 1.58 ± 0.12) was obviously decreased compared with the model group(P<0.05 orP<0.01).Conclusion Luteolin could effectively improve the cognition dysfunction of epileptic rats, and the mechanism might be relevant to regulate the CaM-CaMPK signaling pathway via down-regulation of CaM, CaMPK, as well as Ras protein.
ABSTRACT
Objective To study the effects ofShenqi YizhiGranules (SQYZ) on learning and memory and content of Aβ1-42 of cerebral tissue in 5XFAD mice with Alzheimer’s disease; To discuss its mechanism on improving learning and memory ability of 5XFAD mice.Methods Four-month-old C57BL?6 wild type mice were randomly divided into NS control group and SQYZ control group, and the 5XFAD mice were randomly divided into model group, SQYZ group and huperzine-A (HupA) group, 15 mice in each group. Each group were given same volume for gavage for 60 d. After treatment, the learning and memory ability were evaluated by nesting test, passive avoidance and Morris water maze test. The senile plaques and content of Aβ1-42, ionized calcium binding adapter molecule 1 and glial fibrillary acidic protein in cerebral cortex and hippocampus were detected by immunohistochemical staining and immunofluorescence, respectively.Results Compared with NS control group, the score of nesting test in model group significantly decreased; the step-through latency in passive avoidance was shortened and the escape latentcy in Morris water maze test was prolonged; the quantity of senile plaques and content of Aβ1-42 increased in cerebral cortex and hippocampus; the activation of glial cells significantly increased. In the SQYZ group, the above-mentioned indexes reached or approached the level of wild type control mice. The difference between SQYZ group and model group was statistically significant (P<0.05,P<0.01).Conclusion SQYZ improved learning and memory ability in 5XFAD mice, which may be related to reduction of senile plaques, inhibition of over activation in glial cells and reduction of content of Aβ1-42 in cerebral cortex and hippocampus.
ABSTRACT
Objective To detect the expression of extracellular-regulated kinase (ERK) and phosphatedextracellular-regulated kinase (P-ERK) in the hippocampus after pentylenetetrazoloe-induced status epilepsy and the effects of nimodipine on it.Methods Male Sprague-Dawley adult rats (200-250 g) were randomly divided into normal control group(NC,n =35),status epilepsy group (SE,n =40),nimodipine group (NIM,n =40).The rats were injected first with 40 mg/kg pentylenetetrazoloe(PTZ),followed 10 minutes later by 20 mg/kg PTZ,and subsequently,10 mg/kg PTZ ip every 10 minutes until SE occurred,apoint charactered by a loss of postural control and tonic-clonic seizures.Rats in control group received the same number of saline injections.Rats in NIM group were injected NIM(2.5 mg/kg) intraperitoneally 15 min before the injection of PTZ.Rats in every group were killed at 30 minutes,1 hour,3 hours,12 hours,24 horus,72 hours and 7 days after status epilepsy respectively and the hippocampus were dissected.The expression of ERK and P-ERK in the hippocampus were detected by Western blot.Results Nimodipine attenuated the convulsion of PTZ-induced status epilepsy.There was dynamic expression of P-ERK in SE group.In NIM group,the expression of P-ERK was markedly increased than that of SE group at 30 min,1h,3h,12h,24h,72h,and 7d (3.26 ±0.95 vs 2.56 ±0.82 at 30 min,P＜0.05).Conclusion Nimodipine attenuates the convulsion of PTZ-induced status epilepsy with increased expression of phosphated-ERK in the hippocampus of rats.