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Senile osteoporosis (SOP) is a systemic bone disease characterized by increased susceptibility to fractures. The pathogenesis of SOP is complex and not well understood. Currently, the rapid aging model mouse, senescence accelerated mouse prone 6 (SAMP6), is an ideal model for studying the mechanisms of SOP development and exploring its prevention and treatment. This model exhibits characteristics including increased bone fragility, degradation of bone microstructure, loss of bone matrix, and abnormal metabolism and dysfunction of bone cells, faithfully replicating the process of SOP occurrence and progression at both macroscopic and microscopic levels.
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OBJECTIVE@#To explore the effect of early intervention electroacupuncture (EA) at "Baihui" (GV 20), "Dazhui" (GV 14) and "Shenshu" (BL 23) on the learning-memory ability and the expression of phosphorylated Tau protein in the hippocampus of SAMP8 mice, so as to provide reference for the intervening period of EA for Alzheimer's disease (AD).@*METHODS@#A total of 36 3-month old SAMP8 mice were randomly divided into a model group, a 3-month-old EA group and a 9-month-old EA group, 12 mice in each group. Twelve normal SAMR1 mice with the same age were taken as the control group. The mice in the 3-month-old EA group and 9-month-old EA group were treated with EA at "Baihui" (GV 20), "Dazhui" (GV 14) and "Shenshu" (BL 23) separately 3 months old and 9 months old (continuous wave, 2 Hz, 1.5-2 mA), 20 min each time, once a day, 8 days as a course of treatment, with an interval of 2 days between courses, totally 3 courses of treatment were given. The mice sample in each group was collected at the age of 10 months after the learning-memory ability tested by Morris water maze. The expression of phosphorylated Tau protein in the hippocampus was detected by immunohistochemistry and Western blot, and the expression of Tau mRNA was detected by real-time PCR.@*RESULTS@#Compared with the control group, in the model group, the escape latency was significantly increased (<0.01), the time of stay in the original platform quadrant and the number of crossing the platform quadrant were reduced (<0.01), and the expressions of phosphorylated Tau protein and Tau mRNA in hippocampus were increased (<0.01). Compared with the model group, in the 3-month-old EA group and 9-month-old EA group, the escape latency was significantly reduced (<0.05), the time of stay in the original platform quadrant and the number of crossing the platform quadrant were increased (<0.05), and the expressions of phosphorylated Tau protein and Tau mRNA in hippocampus were reduced (<0.05). Compared with the 9-month-old EA group, in the 3-month-old EA group, the escape latency was significantly reduced (<0.05), the time of stay in the original platform quadrant and the number of crossing the platform quadrant were increased (<0.05), and the expressions of phosphorylated Tau protein and Tau mRNA were reduced (<0.01).@*CONCLUSION@#The early EA intervention could more effectively improve the learning-memory ability and inhibit phosphorylation of Tau protein in the hippocampus of SAMP8 mice.
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Animals , Mice , Disease Models, Animal , Electroacupuncture , Hippocampus , Learning , Memory , tau ProteinsABSTRACT
Objective:To observe the effect of acupuncture on the expression of mitochondrial proteome in hippocampus of senescence-accelerated mouse prone g (SAMPg) mice models with Alzheimer disease (AD),and to explore the possible protective mechanism of acupuncture on mitochondria.Methods:Sixty 6-month-old male SAMP8 mice were randomly divided into an acupuncture at acupoint group,an acupuncture at non-acupoint group and a model group,20 mice in each group.The 20 male senescence-accelerated mouse/resistance 1 (SAMR1) mice of the same age were used as a normal control group.Shenshu (BL 23),Baihui (GV 20),Xuehai (SP 10) and Geshu (BL 17) were selected for acupuncture intervention in acupuncture at acupoint group.After an 8-week intervention,mitochondrial tissues were extracted from the hippocampus.Differentially expressed proteins were identified by subcellular organelle proteomics.Western blot was used to verify the expressions of some related proteins in hippocampal mitochondria.Results:Compared with the model group,there were 13 differentially expressed protein spots in the acupuncture at acupoint group,of which,9 were up-regulated,including neurofilament light polypeptide (NFL),actin (cytoplasmic 1,database ID:ACTB),tubulin beta-2A chain (TBB2A),tropomodulin-2 (TMOD2),pyruvate dehydrogenase E1 component subunit beta (PDHE1-β),NADH-ubiquinone oxidoreductase 75 kDa subunit (database ID:NDUS1),heat shock cognate 71 kDa protein (HSC71),pyruvate dehydrogenase E1 component subunit alpha (PDHE1-α) and ATP synthase beta subunit (ATP-β);4 were down-regulated,including glial fibrillary acidic protein (GFAP),pyruvate dehydrogenase phosphatase 1 (PDP1),mitochondrial-processing peptidase subunit alpha (MMP-α) and adenosine kinase (ADK).According to the information provided in the protein database,most of the differentially expressed proteins involve the regulation of mitochondrial function and structure.The expression levels of NFL and TBB2A in the normal control group and the acupuncture at acupoint group were significantly higher than those in the acupuncture at non-acupoint group (P＜0.05).ATP-β and NDUS1 expression levels were significantly higher in the acupuncture at acupoint group than those in the acupuncture at non-acupoint group (P＜0.05);there was no significant difference between the acupuncture at non-acupoint group and the model group (P＞0.05).Conclusion:Acupuncture may achieve the potential therapeutic effect on AD by regulating the structure and functional proteins of hippocampal mitochondria.
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<p><b>OBJECTIVE</b>To investigate the preventive treatment effects of electroacupuncture (EA) on cognitive changes and brain damage in senescence-accelerated mouse prone 8 (SAMP8) mice.</p><p><b>METHODS</b>The 5-month-old male SAMP8 and age-matched homologous normal aging mice (SAMR1) were adopted in this study. EA stimulation at Baihui (GV 20) and Yintang (EX-HN 3) was performed every other day for 12 weeks, 4 weeks as a course. Morris water maze test and Nissl-stained with cresyl violet were used for cognitive impairments evaluation and brain morphometric analysis. Amyloid-β (A β) expression in hippocampus and parietal cortex was detected by immunohistochemistry, and apoptosis was observed by TUNEL staining.</p><p><b>RESULTS</b>After 3 courses of EA preventive treatment, the escape latencies of 8-month-old SAMP8 mice in EA group were significantly shortened than those of un-pretreated SAMP8 mice. Compared with SAMR1 mice, extensive neuronal changes were visualized in the CA1 area of hippocampus in SAMP8 mice, while these pathological changes and attenuate cell loss in hippocampal CA1 area of SAMP8 mice markedly reduced after EA preventive treatment. Furthermore, A β expression in hippocampus and parietal cortex of SAMP8 mice decreased significantly after EA treatment, and neuronal apoptosis decreased as well.</p><p><b>CONCLUSION</b>EA preventive treatment at GV 20 and EX-HN 3 might improve cognitive deficits and neuropathological changes in SAMP8 mice, which might be, at least in part, due to the effects of reducing brain neuronal damage, decreasing neuronal apoptosis and inhibiting A β-containing aggregates.</p>
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Objective To investigate the alterations of fecal metabolites and intestinal flora during the aging in a mouse model of senescence accelerated mouse prone 8 (SAMP8). Methods The 1H-NMR metabonomics and metagenomics were applied to investigate the aging-related metabolic markers and intestinal flora, and Pearson correlation analysis was performed between metabolites and gut flora. Results Thirty-one endogenous metabolites were identified in the faeces of SAMP8 mice, of which 13 metabolites changed significantly compared with SAMR1 mice. Differential metabolites were mainly enriched in four metabolic pathways: phenylalanine, tyrosine and tryptophan biosynthesis; valine, leucine and isoleucine biosynthesis; phenylalanine metabolism; histidine metabolism. The results showed that the diversity of intestinal flora was significantly changed and the relative abundances of 10 kinds of intestinal flora were significantly changed in 10-month-old SAMP8 mice. Correlation analysis showed that Christensenellaceae was positively correlated with phenylalanine, histidine, valine, isoleucine, and uridylic acid; Dehalobacterium was negatively correlated with tyrosine, and Planococcaceae was negatively correlated with valine. Conclusion This paper reveals the changes of fecal metabolites and gut flora in SAMP8 mice, which provides experimental evidence for the study of aging progress and anti-aging actions of drugs.
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OBJECTIVE To investigate the effects of LW-AFC, a new formula derived from Liuwei Dihuang decoction, on gut microbiota and the behavior of learning and memory of SAMP8 mice, a mouse model of Alzheimer Disease (AD), and identify the specific intestinal microbiota correlating with cognitive ability. METHODS Morris-water maze test, novel object recognition test and shuttle-box test were conducted to observe the ability of learning and memory. 16S rRNA amplicon sequencing (Illumina, San Diego, CA, USA) was employed to investigate gut microbiota. RESULTS The treatment of LW- AFC improved cognitive impairments of SAMP8 mice, including spatial learning and memory ability, active avoidance response, and object recognition memory capability. Our data indicated that there were significantly 8 increased and 12 decreased operational taxonomic units (OTUs) in the gut microbiota of SAMP8 mice compared with senescence accelerated mouse resistant 1 (SAMR1) strains, the control of SAMP8 mice. The treatment of LW- AFC altered 22 (16 increased and 6 decreased) OTUs in SAMP8 mice and among them, 15 OTUs could be reversed by LW-AFC treatment resulting in a microbial composition similar to that of SAMR1 mice. We further showed that there were 7 (3 negative and 4 positive correlation) OTUs significantly correlated with all the three types of cognitive abilities, at the order level, including Bacteroidales, Clostridiales, Desulfovibrionales, CW040, and two unclassified orders. LW-AFC had influences on bacterial taxa correlated with the abilities of learning and memory in SAMP8 mice and restored them to SAMR1 mice. CONCLUSION The effects of LW-AFC on improving cognitive impairments of SAMP8 mice might be via modulating intestinal microbiome and LW-AFC could be used as a potential anti-AD agent.
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Objective To establish an ion-pair reverse-phased high-performance liquid chromatography(RP-HPLC)method for simultaneous determination of ATP,ADP and AMP in the hippocampus of mice. Methods The protein of mouse hippocampus was precipitated with perchloric acid,and neutralized with potassium carbonate-methanol mixture. Mobile phase was as follows:50 mmol/L phosphate buffer(buffer for K2HPO4-KH2PO4,pH 6.60,containing 22%methanol,and 4 mmol/L tetrabutylammonium bisul?fate). Shimadzu HPLC system and Agilent C18 column(4.6 mm×250 mm,5μm)filled with the same material pre-column(12.5 mm× 4.6 mm,5μm)were used. The contents of ATP,ADP and AMP in mouse hippocampus were analyzed at a wavelength of 254 nm,the flow rate of 0.6 ml/min and room column temperature. Results Stability tests showed that intra-day and inter-day precision of the method were 1.27%-3.42%and 0.88%-3.52%,respectively,and recovery rates were 95.67%-104.05%. Conclusion The HPLC method established in this study is simple,accurate and efficient in detecting the levels of ATP,ADP,and AMP in mice hippocampus.
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Objective To establish an ion-pair reverse-phased high-performance liquid chromatography (RP-HPLC) method for simultaneous determination of ATP, ADP and AMP in the hippocampus of mice. Methods The protein of mouse hippocampus was precipitated with perchloric acid, and neutralized with potassium carbonate-methanol mixture. Mobile phase was as follows: 50 mmol/L phosphate buffer (buffer for K2HPO4-KH2PO4, pH 6.60, containing 22% methanol, and 4 mmol/L tetrabutylammonium bisulfate). Shimadzu HPLC system and Agilent C18 column (4.6 mm×250 mm, 5 μm) filled with the same material pre-column (12.5 mm×4.6 mm, 5 μm) were used. The contents of ATP, ADP and AMP in mouse hippocampus were analyzed at a wavelength of 254 nm, the flow rate of 0.6 ml/min and room column temperature. Results Stability tests showed that intra-day and inter-day precision of the method were 1.27%-3.42% and 0.88%-3.52%, respectively, and recovery rates were 95.67%-104.05%. Conclusion The HPLC method established in this study is simple, accurate and efficient in detecting the levels of ATP, ADP, and AMP in mice hippocampus.
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Aim To investigate the effect of preventive administration of icariin on learning and memory abili-ties and brain mitochondrial oxidative stress in senes-cence-accelerated mouse prone8 ( SAMP8 ) . Methods The 6-month-old SAMP8 mice were randomly divid-ed into the SAMP8 model group, ICA groups (75, 150 mg · kg-1 ) , the positive Diethylstilbestrol ( DES ) group and estrogen receptor inhibitor ICI182780 com-bined with ICA (150 mg·kg-1 ) group, with 8 mice in each group. 8 same month old SAMR1 mice were selected as the normal control group. After oral admin-istration for 8 weeks, Morris water maze test and step-down passive test were used to investigate the effects of preventive administration of ICA on learning and mem-ory abilities in SAMP8 mice. Cerebral cortex mitochon-dria were isolated to determine the effect of preventive administration of ICA on the oxidative stress by detec-ting reactive oxygen species ( ROS) level, lipid perox-ides ( MDA ) content, glutathione GSH content and catalase ( CAT ) activity. Results Preventive treat-ment of ICA could significantly improve the abilities of place navigation and space exploration of SAMP8 mice, enhance their reflex ability in step-down passive test. ICA could also reduce the level of ROS and MDA content, increase GSH content in brain mitochondria of SAMP8 mice. CAT activity was not obviously changed. Compared with ICA high dose group, the learning and memory abilities of mice in ICA and estrogen receptor inhibitor ICI182780 co-administrated group were signif-icantly decreased. However,brain mitochondria oxida-tive stress was not changed obviously. Conclusion Preventive administration of icariin can significantly improve learning and memory abilities and brain mito-chondrial oxidative stress in SAMP8 mice. The mecha-nism of ICA improving learning and memory abilities may be related to its estrogen-like effect;while the ac-tion on brain mitochondrial oxidative stress may be in-dependent of estrogen receptor.
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Objective To investigate degenerative changes of auditory functions and age -related expression of phosphorylated extracellular signal -regulated protein kinases1/2(p-ERK1/2) in the cochlea of the senescence accelerated mouse .Methods The 3 ,5 ,7 months old mice were selected for the study and each group had 6 mice . The 8 kHz tone burst auditory thresholds and age -related expression of p -ERK1/2 in the cochlea were studied in the senescence accelerated mouse/prone 8(SAMP8) at 3 ,5 ,7 months .The expression of p -ERK1/2 was analyzed by the optical density of immunohistochemical staining .Results For the auditory function evaluation :The SAMP 8 developed a progressive hearing loss at 8 kHz which showed an age -related significant increase (P< 0 .05) .The ABR thresholds in 3 ,5 ,7 months old groups in the left ear were 31 .817 ± 1 .228 ,54 .329 ± 1 .459 ,58 .330 ± 1 .252 dB SPL ,respectively .In the right ears ,the ABR threshold were 32 .474 ± 1 .041 ,53 .485 ± 1 .385 ,57 .842 ± 1 .173 dB SPL ,respectively .p-ERK1/2 protein expressed in the cochlea of the SAMP8 throughout the development sta‐ges ,which developed an age-related significant decrease (P<0 .05) .The average optical density of p -ERK1/2 in the spiral ganglion cells in the 3 ,5 ,7 months old mice were 0 .699 7 ± 0 .018 8 ,0 .621 5 ± 0 .014 7 ,0 .575 3 ± 0 .015 5 ,respectively .In the hair cells ,they w ere 0 .651 9 ± 0 .025 2 ,0 .591 2 ± 0 .010 2 ,0 .559 3 ± 0 .006 7 respec‐tively .Conclusion The expression level of p -ERK1/2 protein decreases when the SAMP 8 develops a progressive hearing loss .This indicates that p-ERK1/2 protein probably has relationship with maintaining functional status of the cochlea and the auditory formation .
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Objective To explore hearing loss , the expression of age-related changes of nerve growth factor receptor TrkA (NGFR TrkA ) in the cochlea of the senescence-accelerated mouse. Methods The senescence accelerated mouse/prone 8(SAMP8) at 3, 5, 7 months were chosen as analyzing subjects. The auditory thresholds was monitored by auditory brainstem respons (ABR). The expression of NGFR TrkA protein was analyzed by the optical density of immunohistochemical staining. Results The SAMP8 developed a progressive auditory threshold which showed an age-related significant increase (P < 0.05). There were NGFR TrkA protein expressed in the cochlea of the SAMP8 throughout the development, which developed an age-related significant descend (P<0.05). Conclusion The expression level of NGFR TrkA protein decreases when the SAMP 8 develops a progressive hearing loss which indicates that NGFR TrkA protein probably has relationship with maintaining functional status of the cochlea.
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The physiological and bio-marker function of D-acidic amino acids is now becoming the hot topic on metabolomics study and new drug discovery. A fully automated two-dimensional high performance liquid chromatography (2D-HPLC) system was established by using monolithic ODS column as the first dimension column, acetonitrile-trifluoro acetic acid-water (9: 0. 05: 92, V/ V) as the mobile phase; micro Chiralpak QD-1-AX column as the enantiomer separation column, 10 mmol/ L citric acid in methanol-acetonitrile (50: 50, V/ V) as the mobile phase for the second dimension, 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) as the fluorometrical derivative reagent. The separation efficiency ( Rs > 2. 5), determination sensitivity ( LOD =1 fmol) of acidic amino acids enantiomers were higher than those of existing methods, and an online confirmation of the enantiomers amounts was also achieved using this system. The recoveries were around 97-104% , RSD values for intra-day and inter-day precision were less than 5% for the acidic amino acids enantiomers in the biological samples. Furthermore, by analyzing the aging model senescence accelerated mouse prone 1 (SAMP1) mice which have low immunocompetence, the amounts of D-aspartic acid in thymus and spleen were determined as (206±18) and (264±21) nmol/ g, respectively. It is the first time that an obvious trend of the increasement of D-aspartic acid (p<0. 01) was observed in thymus and spleen of SAMP1 mice compare to senescence accelerated mouse resistant 1 (SAMR1) mice.
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Objective To investigate the effects of rhein lysinate (RHL)on the expressions of TNF-α,IL-6 and NF-κB in the kidney tissue of senescence accelerated mouse prone 10 (SAMP 10)mice.Methods We selected 1 8 male mice (SAMP 1 0 )aged 7 months for the study and randomly divided them into blank control group and groups of different concentrations of RHL;six senescence accelerated mouse resistance 1 (SAMR 1 )served as the young control group.After 6 weeks’ treatment,HE staining was used to detect the pathological changes of the kidney.The expressions of TNF-α,IL-6 and NF-κB at the protein level were detected by immunohistochemistry and Western blotting.Results RHL treatment did not affect the body weight of SAMP 10 mice (P>0.05 ). Compared with SAMR 1 mice, contracted and destroyed renal glomeruli and infiltration of mononuclear macrophages were observed in control SAMP10 mice.However,this pathological process was blocked by RHL (25 mg/kg and 50 mg/kg ) treatments. In addition, the overexpressions of TNF-α, IL-6 and NF-κB and the phosphorylation of NF-κB in the kidney tissue of SAMP 10 mice could be inhibited by RHL treatments (P<0.05). Conclusion RHL inhibits the inflammatory reaction of the kidney tissue,which may be one of the mechanisms by which RHL exerts its kidney-protecting and anti-aging effects.
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Objective To investigate the improving effect of Hedysari radix polysaccharide on the behavior and its influence on cerebral central neurotransmitters in senescence accelerated mouse prone 8 (SAMP 8).Methods The senescence accelerated mice 8 were randomly divided into a model group,a Hedysari radix polysaccharide (HRP) group and a aricept group.SAMRl were served as the control group.After intragastrical treatment for 3 months,the behavior changes and the levels of norepinephrine (NE),dopamine (DA),5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) were observed respectively by applying Morris water maze and high performance liquid chromatography (HPLC).Results In the SAMP8 model group,the hidden platform test showed that the latency to find the hidden platform was remarkably prolonged,the latency range from third day to fifth day was (55.31 ±9.62) s,(58.67± 10.89) s,(58.45± 10.53) s,respectively.The level ofNE、DA、5-HT and 5-HIAA was (4.97± 1.74) mmol/L,(1.63±0.57)mmol/L,(4.29±0.94)mmol/L,(2.91±0.85)mmol/L respectively,significantly reduced (P＜0.01).Compared with model group,the latency of hidden platform test was (44.73 ± 9.83) s,(40.53±8.37)s,(44.75±9.16)s respectively,which were remarkably shortened.The expression level ofNE,DA,5-HT and 5-HIAA in the HRP treatment group was (7.58± 1.62) mmol/L,(3.25 ±0.70) mmol/L,(7.04±0.95) mmol/L,(4.62±0.79) mmol/L respectively,which obviously increased (P＜ 0.05).Conclusion HRP could improve learning and memory ability of SAMP8 and the effect may related to up-regulate the expression level of cerebral Central neurotransmitters.
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Objective To observe the effects of voluntary exercise on the learning ability, memory and hippocampus growth-associated protein 43 (GAP43) expression in senescence-accelerated prone mouse (SAMP8), so as to explore the possible mechanism of exercises on improving the cognitive ability and delaying aging. Methods A total of 60 three-month old female SAMP8 mice were evenly assigned to running cage environment (RCE) group and standard environment (SE) group at random. After three months, Morris water maze test was used to test the platform-seeking latency and search strategy. Then 10 mice were sacrificed in each group for RT-PCR analysis of hippocampus GAP43 mRNA expression, 10 for Western blotting analysis of hippocampus GAP43 protein expression, and 10 for immunohistochemistry staining of hippocampus GAP43 expression. Results Morris water maze test showed that RCE mice had a significant shorter platform-seeking latency than SE mice(P<0. 01, P<0. 05), and RCE mice had a significant longer time in the first quadrant (P<0. 01) and a shorter time in the fourth quadrant (P<0. 05) compared with SE mice. RCE mice had a significantly higher GAP43 expression in the hippocampus compared with SE mice (P<0. 01). Conclusion Voluntary exercise can improve the learning ability and memory of SAMPS, which might be associated with the increase of GAP43 in the hippocampus.
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@#Alzheimer's disease (AD) is a neurodegenerative disorder characterized by memory loss and cognitive decline. The pathological eatures of Alzheimer's disease are abnormal deposition of amyloid beta-peptides (Aβ), neurofibrillary tangles, cholinergic deficits, and loss of synaptic processes and dendritic spines. Senescence accelerated mouse prone 8 exhibits age-related deficits of learning and memory from an early age, tau protein phosphorylation, neurotransmitter changes, synaptic structure and function disorders, circadian rhythm disorders,as well as gene expression and many other characteristic changes, which are consistent with Alzheimer's disease pathological changes，and can be used as an ideal animal model for Alzheimer's disease prevention drugs development.
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Objective To investigate the influence of acupuncture therapy on neural stem cell (NCS) proliferation and differentiation in the hippocampus of the senescence-accelerated prone-8 (SAP8) mouse. Methods Twenty-four SAP8 mice were randomly and equally divided into a model group and an acupuncture group. Twelve senescence-accelerated resistant ( SAR1 ) mice served as the control group. Acupuncture was administered at the Baihui (DU20) point to mice in the acupuncture group once daily for 21 consecutive days. Bromodeoxyuridine (BrdU) was used to detect the proliferation and differentiation of NCSs in the hippocampus through double-labeled immunofluoresSAR1 group, the positive cells in the SAP8 group were significantly fewer Compared to the SAP8 group, positive cells markers of neuron or glia cell positive cells appeared. Compared to the SAR1 group, the expression of BrdU/GFAP increased in the SAP8 group, and decreased after acupuncture but not significantly. BrdU/S-100 β cells decreased significantly in the SAP8 group, and increased after acupuncture, but again not significantly. Compared to the SAR1 group BrdU/GalC positive cells increased significantly in the SAP8 group and decreased significantly after acupuncture.Conclusions After acupuncture treatment for 21 days, the differentiation of hippocampal NSCs into oligodendrocytes was inhibited, but there was little effect on their differentiating into neurons and immature astrocytes.
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Objective: To investigate the effects of Liuwei Dihuang decoction (LW), its San-bu (three tonics) and Sanxie (three eliminators) ingredients on regulating the mmune function of senescence-accelerated mice (SAM). Methods: SAM-prone (SAMP) 8 mice were orally administrated with LW (10 g/kg), San-bu (6.4 g/kg) and San-xie (3.6 g/kg) respectively, once per day for 60 days, while SAM-resistant ( SAMR) 1 mice administrated with distilled water as control group. 3H-TdR incorporation was applied for detecting splenocyte proliferation. Flow cytometry (FCM) was used to observe the percentage of CD3+, CD4+,CD8+ and CD19+ ymphocytes in the spleens. Results: Compared with SAMR1 group, the splenocyte proliferation induced by ConA an LPS, percentages of CD3+, CD4 +, CD8+ and CD19+ lymphocytes and ratios of CD3+/CD19+ and CD4+/CD8+ in spleens decreased, while percentage of CD19+ lymphocytes increased in SAMP8 group. After administration of LW, San-bu and San-xie, the above ndexes were mproved to various degrees. LW showed better effects on improving LPS-induced splenocyte proliferation, percentages of CD3+, CD19+ and CD4+ lymphocytes, and the ratios of CD3+ /CD19+ and CD4+/CD8+ than San-bu and San-xie. San-bu showed better effect on mproving ConA-induced splenocyte proliferation than LW and San-xie, and better effect on mproving the percentages of CD3+, CD19+ and CD4+ lymphocytes in the spleens and the ratios of CD3+/CD19+ than San-xie, while San-xie had better effect on regulating CD4+/CD8+ ratio than San-bu. Conclusion: These results suggest that LW regulates the function of T and B lymphocytes and the mbalance of subsets of CD4+ and CD8+ lymphocytes in the spleens of SAMP8. LW shows better effects than San-bu or San-xie used alone, while San-bu and San-xie have their particular effects. The effects of LW on regulating the immune function might be the integral results of San-bu and San-xie. The results provid some experimental evidences for revealing the compatibility of LW.
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Objective: To investigate the acute damage of the nigrastriatal system in SAMP8 mouse after treatment with MPTP and its relationship with microglial activation. Methods: Totally 57 male SAMP8 mice were randomly divided into two groups,control group and MPTP group. Mice were sacrificed (each time 6-9 mice) at 6 h, 24 h, 3 d, and 8 d after the first injection in each group. Mice were subcutaneously injected with normal saline or MPTP (20 mg/kg) at an interval of 2 h for 4 times. The changes of spontaneous activity of mice were observed after injection. The changes of TH+ (tyrosine hydroxylase positive) neuronal numbers in the substantial nigra,TH-ir (tyrosine hydroxylase immunoreactivity), and microglial activation in striatum were examined by immunohistochemistry; striatal dopamine (DA) levels were determined by HPLC. Results: The spontaneous activity of SAMP8 mice was decreased significantly after the third injection, and recovered at 48 h after the first injection. Compared with the control group,the TH+ neurons in MPTP group decreased by 7.06% at 6 hours (P=0.235),by 12.79% at 24 hours(P<0.05), by 22.49% at 3 days(P<0.01),and by 42.39% at 8 days(P<0.001); there was significant difference in the TH+ neurons between the 3 days and 8 days (P<0.05). The corrected optical densities (COD) of TH-ir in the striatum in MPTP group were significantly lower than those in the control group at different time points (6 h, [P<0.05],24 h [P<0.01],3 d[P<0.001],8 d[P<0.001]); there was significant difference between the 24 h and 3 days groups (P<0.05). Compared with the control group,the striatal dopamine (DA) levels decreased by 79.09% at 6 hours (P<0.001),by 80.3% at 24 hours (P<0.001), by 86.6% at 3 days (P<0.001),and by 81.0% at 8 days (P<0.001); there were no significant difference between the 24 h, 3 days, and 8 days. The immunoreactivity of microglial greatly increased at 24 hours, further activated at 3 days,and largely abated at 8 days after MPTP injection. Conclusion: MPTP can cause acute damage to substantia nigra of SAMP8 mice, resulting in reduced spontaneous activity and dopaminergic neurons loss; the activation of microglial might be related to the nigrostriatum damage of MPTP-SAMP8 mice.
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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.