This paper aims to evaluate the pharmacodynamic effect and mechanism of Zhifuxin in the prevention and treatment of vascular dementia(VD), providing a theoretical basis for later development. Bilateral common carotid artery ligation in male Wistar rats was conducted to replicate the long-term hypoperfused VD model, and the drug was given to groups after one month. The rats were fed daily with nimodipine of 20 mg·kg~(-1), Zhifuxin of 50, 100, and 200 mg·kg~(-1), or the same volume of solvent for four weeks. 24 hours after the last dose, Morris water maze experiments were performed to detect the learning and memory abilities of rats. Hematoxylin-eosin(HE) staining was used to observe the pathological changes in the brain tissue of rats; the immunohistochemical method was used to detect the expression of muscarinic acetylcholine receptors M1 and M4 in rats and determine the content of acetyl choline(Ach), acetylcholin esterase(AchE), malondialdehyde(MDA), choline acetyl transferase(ChAT), and dimethyl arginine hydrolase 1(DDAH1) in the cerebral cortex of rats. Western blot was employed to detect protein expression of endothelial nitric oxide synthase(eNOS), caveolin-1, monoamine oxidase A(MAO-A), and monoamine oxidase B(MAO-B). RT-qPCR was utilized to detect mRNA expression of eNOS, caveolin-1, MAO-A, and MAO-B. The results showed that compared with the model group, the different doses of Zhifuxin were able to shorten the latency of VD rats in the water maze positioning navigation test, increase the number of crossing platforms in the space exploration test, and alleviate cone cell contracture in the hippocampus of VD rats. The expression of biochemical indicators related to the cholinergic system in the cerebral cortex: M1 and M4 receptors increased, as well as ChAT activity, and AchE activity significantly decreased. The protein and mRNA expression of indicators related to the eNOS/NO pathway: DDAH1 content, eNOS, and caveolin-1 increased, and that of indicators related to monoamine oxidase(MAO): MAO-A and MAO-B significantly decreased. The results show that Zhifuxin can improve cognition ability in long-term hypoperfused VD rats, and its mechanism of action may be related to its ability to modulate the cholinergic system and the eNOS/NO pathway and inhibit MAO expression.
Animals ; Dementia, Vascular/metabolism* ; Male ; Rats, Wistar ; Rats ; Drugs, Chinese Herbal/administration & dosage* ; Maze Learning/drug effects* ; Nitric Oxide Synthase Type III/genetics* ; Acetylcholinesterase/metabolism* ; Humans ; Choline O-Acetyltransferase/genetics* ; Disease Models, Animal

OBJECTIVETo examine the effect of icariin (ICA) on the cognitive impairment induced by traumatic brain injury (TBI) in mice and the underlying mechanisms related to changes in hippocampal acetylation level.

METHODSThe modifified free-fall method was used to establish the TBI mouse model. Mice with post-TBI cognitive impairment were randomly divided into 3 groups using the randomised block method (n=7): TBI (vehicle-treated), low-dose (75 mg/kg) and high-dose (150 mg/kg) of ICA groups. An additional sham-operated group (vehicle-treated) was employed. The vehicle or ICA was administrated by gavage for 28 consecutive days. The Morris water maze (MWM) test was conducted. Acetylcholine (ACh) content, mRNA and protein levels of choline acetyltransferase (ChAT), and protein levels of acetylated H3 (Ac-H3) and Ac-H4 were detected in the hippocampus.

RESULTSCompared with the sham-operated group, the MWM performance, hippocampal ACh content, mRNA and protein levels of ChAT, and protein levels of Ac-H3 and Ac-H4 were signifificantly decreased in the TBI group (P<0.05). High-dose of ICA signifificantly ameliorated the TBI-induced weak MWM performance, increased hippocampal ACh content, and mRNA and protein levels of ChAT, as well as Ac-H3 protein level compared with the TBI group (P<0.05).

CONCLUSIONICA improved post-TBI cognitive impairment in mice by enhancing hippocampal acetylation, which improved hippocampal cholinergic function and ultimately improved cognition.

Acetylation ; Acetylcholine ; metabolism ; Animals ; Brain Injuries, Traumatic ; complications ; Choline O-Acetyltransferase ; genetics ; metabolism ; Cognitive Dysfunction ; drug therapy ; etiology ; Flavonoids ; chemistry ; pharmacology ; therapeutic use ; Hippocampus ; pathology ; Histones ; metabolism ; Homeostasis ; drug effects ; Male ; Maze Learning ; drug effects ; Mice ; RNA, Messenger ; genetics ; metabolism

OBJECTIVETo study the mechanism of learning and memory dysfuction in the transgenic mouse expressing human tau 40 isoform with P301L mutation (F10).

METHODSThe human tau protein expression and phosphor-tau protein levels were detected with Western blot method. The neurofibrillary tangles were observed with Bielshowsky silver stain. The behavior changes of learning and memory were observed by open field test and passive avoidance test. Acetyleholine level, activities of acetycholinesterase and choline acetyltransferase of whole brain was detected by colorimetry method. The nitric oxide level of whole brain was detected by nitrate enzyme reduction method.

RESULTSExogenous human tau gene was expressed and an elevation of phosphor-tau protein level in 7 and 3-month transgenic mice's hippocampus andcerebrocortex was observed. The neurofibrillary tangles were observed in cerebrocortex of 7-month transgenic mice; the 7-month transgenic mice also presented an evident reduction of learning and memory ability and nitric oxide level of the whole brain, but not changes in acetylcholine level, acetycholinesterase activity, choline acetyltransferase activity and expression in whole brain.

CONCLUSIONTau transgenic mice (F10) can still inherit their parents' biologiccal characters, and develop learning and memory dysfunction awnodh san obvious decrease in nitric oxide level of whole brain in the 7-month old mice, suggesting a decrease of nitric oxide level of whole brain would be involved in the mechanism of learning and memory dysfunction in these transgenic mice.

Acetylcholine ; metabolism ; Acetylcholinesterase ; metabolism ; Animals ; Brain ; physiopathology ; Choline O-Acetyltransferase ; metabolism ; Humans ; Membrane Proteins ; genetics ; Memory Disorders ; genetics ; physiopathology ; Mice ; Mice, Transgenic ; Mutation ; Nitric Oxide ; metabolism

OBJECTIVETo investigate the effects of beta-amyloid (Aβ) and apolipoprotein E4(apoE4) on choline acetyl transferase (ChAT) in hippocampus and to explore possible the synergistic effect of both Aβ and apoE4.

METHODSMale Wistar rats were divided into four groups: control group, Aβ group, apoE4 group and Aβ + apoE4 group. Rats in different group received injection of normal saline, Aβ1-40, apoE4 and Aβ1-40 + apoE4, respectively, into bilateral hippocampus CA1 regions under the control of a brain stereotaxic apparatus. The learning-memory ability with the escape latency and the times of passing platform and the expression of ChAT in hippocampus CA1 regions were documented.

RESULTSThe escape latency at fifth day and the times of passing platform and ChAT mRNA PU values were obtained for the control group (10.75 s ± 2.44 s, 4.13 ± 0.64, and 28.90 ± 4.43), apoE4 group (23.88 s ± 4.32 s, 2.38 ± 0.52, and 20.85 ± 3.98), Aβ group (43.50 s ± 9.78 s, 1.38 ± 0.52, and 16.96 ± 2.53), and Aβ + apoE4 group (70.63 s ± 10.04 s, 0.75 ± 0.71, and 13.01 ± 2.21). Through 5 days of training all animals acquired learning-memory ability with the gradually shortened escape latency, although injection of Aβ1-40 and apoE4 all induced learning-memory damage, due to a significantly prolonged the escape latency at fifth day (P < 0.01) and markedly decreased the times of passing platform (P < 0.01) in both Aβ and apoE4 group than in control group. An interaction between Aβ and apoE4 also was observed, with further prolonged escape latency(P < 0.01). ChAT mRNA PU values were significantly lower in the Aβ group and apoE4 group than in the control group (P < 0.01). Aβ and apoE4 demonstrated interaction in lowering ChAT mRNA level(P < 0.05).

CONCLUSIONSBoth Aβ and apoE4 induce an injury to hippocampal cholinergic system and its learning-memory ability, in which Aβ and apoE4 have a synergistic effect in the initiation of such injury.

Alzheimer Disease ; enzymology ; physiopathology ; Amyloid beta-Peptides ; toxicity ; Animals ; Apolipoprotein E4 ; toxicity ; CA1 Region, Hippocampal ; enzymology ; physiology ; Choline O-Acetyltransferase ; genetics ; metabolism ; Drug Synergism ; Escape Reaction ; drug effects ; Learning ; drug effects ; Male ; Memory ; drug effects ; RNA, Messenger ; metabolism ; Random Allocation ; Rats ; Rats, Wistar

OBJECTIVETo observe the effects of repeated electroacupuncture (EA) of Zusanli (ST36)- Yanglingquan (GB34) on hypothalamic acetylcholinesterase (AchE) and vesicular acetylcholine (ACh) transporter (VAChT) activities and choline acetyltransferase (ChAT) mRNA and muscarinic M1 receptor (M1R) mRNA expression in chronic constrictive injury (CCI) and/or ovariectomy (OVX) rats so as to reveal its underlying mechanism in cumulative analgesia.

METHODSA total of 103 female Wistar rats were randomly divided into normal control (n =15), CCI (n =15), CCI+EA2d (n =15), CCI+EA2W (n =15), OVX+CCI =13), OVX+CCI+EA2d (n =15), and OVX+CCI+EA2W groups (n =15). CCI model was established by ligature of the unilateral sciatic nerve with surgical suture. Memory impairment model was established by removal of the bilateral ovaries. Morris water test was conducted to evaluate the OVX rats' memory learning ability, and the thermal pain threshold (PT) of the bilateral paws was detected the next morning after EA. EA (2/15 Hz, 1 mA) was applied to bilateral ST36-GB34 for 30 min, once daily for 2 days or 2 weeks, respectively. Hypothalamic AChE activity was detected by histochemistry, VAChT immunoactivity was determined by immunohistochemistry, and ChAT mRNA and M1R mRNA expressions were assayed by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSIn comparison with the normal control group, the AChE activity in hypothalamic arcuate nucleus (ARC) and supraoptic nucleus (SON) regions of CCI group, AChE activity in paraventricular nucleus (PVN), ARC, and SON regions of OVX+CCI group, and hypothalamic muscarinic M1R mRNA expression levels in both CCI and OVX+CCI groups were down-regulated significantly (P <0.05). Compared with the CCI group, the AChE activities in hypothalamic ARC and SON regions of CCI+EA2d and CCI+EA2W groups and PVN region of CCI+EA2W group and hypothalamic ChAT mRNA and M1R mRNA expression levels in CCI+EA2W group were up-regulated considerably (P <0.05). In comparison with the OVX+CCI group, the AChE activities in PVN, ARC, and SON regions and the expressions of hypothalamic ChAT mRNA and VAChT in ARC region of OVX+CCI+EA2W group were up-regulated remarkably (P <0.05). The effects in rats of CCI+EA2W group were evidently superior to those of OVX+CCI+EA2d group in up-regulating AChE activities in PVN, ARC, and SON regions, VAChT immunoactivity in ARC region, and expression levels of hypothalamic ChAT mRNA and M1R mRNA (P <0.05). Similar situations were found in OVX+CCI rats after EA2W. It suggested a cumulative effect after repeated EA of ST36-GB34. Comparison between CCI+EA2W and OVX+CCI+EA2W groups showed that the effects in rats of the former group were evidently better than those of the latter group in up-regulating AChE activity in ARC and SON regions and the expressions of hypothalamic ChAT mRNA and M1 mRNA (P <0.05), suggesting a reduction of EA2W effects after OVX.

CONCLUSIONRepeated EA can significantly up-regulate AChE and VAChT activities and ChAT mRNA and M1R mRNA expressions in the hypothalamus of CCI and OVX+CCI rats, which may contribute to the cumulative analgesic effects of repeated EA and be closely related to the animals' neuromemory ability.

Acetylcholinesterase ; genetics ; metabolism ; Acupuncture Analgesia ; Animals ; Choline O-Acetyltransferase ; genetics ; metabolism ; Cholinergic Agents ; metabolism ; Chronic Pain ; enzymology ; metabolism ; pathology ; Constriction, Pathologic ; Electroacupuncture ; Female ; Gene Expression Regulation ; Hypothalamus ; enzymology ; metabolism ; pathology ; Neuralgia ; enzymology ; metabolism ; pathology ; Ovariectomy ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Wistar ; Receptor, Muscarinic M1 ; genetics ; metabolism ; Vesicular Acetylcholine Transport Proteins ; genetics ; metabolism

OBJECTIVETo observe the effects of auricular acupuncture on the learning and memory abilities of model rats with Alzheimer's disease (AD), and investigate its mechanism.

METHODSThirty SD rats were randomly divided into a control group, a model group and an auricular acupuncture group, 10 rats in each group. The model rats with AD were established by multiple injections with Okadaic Acid into the CA1 region of hippocampus. In the control group, the same quantity injection with Dimethyl Sulfoxide (DMSO) was applied on experimental rats. The auricular acupoints of "Nao" (brain) and "Shen" (kidney) were used for treating in the auricular acupuncture group, in contrast, the auricular region were not treated in the model and the control groups. The learning and memory capabilities of the rats were assessed with Morris Water Maze behavioral test, and the expressions of choline acetyltransferase (ChAT) and glial fibrillary acidic protein (GFAP) were examined by immunohistochemistry.

RESULTSComparing with the model group, the treated AD rats with auricular acupuncture was showed that the average escape latency was obviously shortened in the place navigation test (P<0.01), the movement time in plateform quadrant was obviously prolonged in the spatial probe test (P<0.05), and the number of traversing platform obviously increased (P<0.01) after the platform was taken away. The expression of ChAT increased in the hippocampus and cortex (P<0.01, P<0.05), but the expression of GFAP obviously decreased in the CA1 region of hippocampus (P<0.01).

CONCLUSIONAuricular acupuncture can improve the learning and memory capability of the model rats with AD. Its mechanism might be related with decreasing cholinergic neuron damage and reducing the abnormal activation and hyperplasia of astrocyte.

Acupuncture, Ear ; Alzheimer Disease ; genetics ; metabolism ; psychology ; therapy ; Animals ; Choline O-Acetyltransferase ; genetics ; metabolism ; Disease Models, Animal ; Gene Expression ; Glial Fibrillary Acidic Protein ; genetics ; metabolism ; Humans ; Male ; Memory ; Random Allocation ; Rats ; Rats, Sprague-Dawley

The purpose of the present study was to investigate the mechanism of the effect of estrogen on the production of acetylcholine in the brain and to study the regulatory role of acupuncture of Zusanli acupoint in acetylcholine production in the brain of ovariectomized rats. Experimental female Wistar rats were divided into three groups: intact group (INT), ovariectomized group (OVX), and ovariectomy and acupuncture group (OVX+AC). Radioimmunoassay (RIA) was used to measure the estrogen content in plasma. The mRNA expression of choline-acetyltransferase (ChAT) and glyceraldehyde phosphate dehydrogenase (GAPDH) in the brain of rats was measured by the RT-PCR technique and was tested by the method of agarose gel electrophoresis. The ChAT mRNA positive neurons in the hippocampus were observed by using in situ hybridization and the results were processed with a computerized image analysis system. The results are as follows. Compared with the control animals, the plasma estrogen level was significantly lowered in ovariectomized animals. However, the plasma estrogen level was higher in the OVX+AC group than that of the OVX group. The ChAT mRNA expression level of OVX+AC group was higher than that of the OVX group. The area and integral optical density of the ChAT mRNA positive neurons in the hippocampus increased more obviously in OVX+AC group than in the OVX group. The experimental results observed indicate that the expression of ChAT gene in the brain is possibly related to the estrogen level in the body. The expression of ChAT gene in the brain of the ovarietomized rat can be regulated by acupuncture of Zusanli acupoint and it may be one of the mechanisms that acupuncture increases acetylcholine content in the brain.
Acupuncture ; Animals ; Brain ; enzymology ; Choline O-Acetyltransferase ; biosynthesis ; genetics ; Estrogens ; blood ; Female ; Hippocampus ; enzymology ; Ovariectomy ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Rats, Wistar