miR-142通过FMRP介导上调APP/PS1小鼠海马神经元PSD95和Synapsin I表达改善学习记忆能力

目的 探讨miR-142通过FMRP介导调控APP/PS1小鼠海马神经元内PSD95和Synapsin I的表达及对学习记忆能力的影响。方法 将10月龄APP/PS1小鼠随机分成AD组、sh-miR-NC组、sh-miR组,同月龄的C57BL/6小鼠作为Control组,利用Morris水迷宫行为学实验检测小鼠的学习记忆能力,用Western blot和免疫荧光方法检测FMRP、PSD95和Synapsin I在各组小鼠海马神经元中的表达情况。结果 APP/PS1小鼠学习记忆能力明显下降;沉默miR-142明显改善APP/PS1小鼠的学习记忆能力,使APP/PS1小鼠海马神经元低表达的FMRP、PSD95和Synapisin I等蛋白逆转上调。结论 miR-142通过结合FMRP上调APP/PS1小鼠海马神经元内PSD95和Synapsin I的表达水平,改善学习记忆能力。     

鹿茸多肽对APP/PS1双转基因小鼠Rho/ROCK通路的影响

目的 探讨鹿茸多肽(VAP)对APP/PS1双转基因小鼠Rho/ROCK通路的影响.方法 APP/PS1双转基因小鼠随机分为模型组和鹿茸多肽组,每组20只,另以同窝同性别阴性小鼠20只设立为对照组.鹿茸多肽组小鼠鹿茸多肽100 mg/kg灌胃给药,每天1次,连续28 d.治疗后水迷宫实验检测并记录小鼠逃避潜伏期和穿越平...     

APP/PS1双转基因AD小鼠早期内质网应激诱导的凋亡

目的观察APP/PS1双转基因AD小鼠神经细胞凋亡,及内质网分子伴侣葡萄糖调节蛋白（GRP78）和内质网促凋亡因子半胱氨酸蛋白酶-12（Caspase-12）表达的改变,探讨APP/PS1双转基因AD小鼠早期内质网应激诱导的凋亡。方法选取5、7月龄的APP/PS1双转基因小鼠和同月龄同背景的野生型小鼠（WT）,分为5月龄WT组、5月龄APP/PS1组、7月龄WT组和7月龄APP/PS1组,每组6只,应用原位细胞凋亡检测法（TUNEL）检测凋亡细胞,免疫组织化学方法检测其脑内GRP78和Caspase-12的表达水平。结果 TUNEL检测凋亡率分别为7月龄APP/PS1鼠（35.0±6.31）%、5月龄APP/PS1鼠（9.0±2.78）%、7月龄WT鼠（4.0±1.89）%、5月龄WT鼠（4.0±1.83）%,其中7月龄APP/PS1鼠凋亡率显著升高（P〈0.05）;免疫组织化学检测GRP78阳性率分别为7月龄APP/PS1鼠（30.0±5.43）%、5月龄APP/PS1鼠（10.0±2.12）%、7月龄WT鼠（2.0±1.71）%、5月龄WT鼠（3.0±1.41）%,7月龄APP/PS1鼠GRP78表达明显升高（P〈0.05）;免疫组织化学检测Caspase-12阳性率分别为7月龄APP/PS1鼠（33.0±5.98）%、5月龄APP/PS1鼠（12.0±2.60）%、7月龄WT鼠（4.0±2.56）%、5月龄WT鼠（2.0±1.79）%,7月龄APP/PS1鼠Caspase-12表达明显升高（P〈0.05）。结论 7月龄的APP/PS1双转基因小鼠出现了内质网应激诱导的凋亡。本实验结果为临床AD早期预防和治疗提供了重要依据。     

基于齿状回神经元树突棘形态探讨ROCK2敲减改善APP/PS1小鼠认知功能的作用机制

目的：观察海马区敲减Rho相关激酶2(ROCK2)对阿尔茨海默病模型APPswe/PS1dE9(APP/PS1转基因小鼠的干预效果，并探索其对海马齿状回区神经元树突棘形态的影响及潜在机制。方法：选用雄性8月龄的C57BL/6及APP/PS1小鼠，随机分为4组，分别为野生型（WT）组（8只）、APP/PS1小鼠生理盐水（NS）组（8只）、APP/PS1小鼠敲减对照（shRNA）组（12只）和APP/PS1小鼠ROCK2敲减（shROCK2）组（12只）。通过腺相关病毒共转染shRNA的方法，下调APP/PS1转基因小鼠双侧海马区神经元ROCK2蛋白表达，实现海马区局部神经元ROCK2敲减。利用水迷宫和Y迷宫实验检测小鼠的认知功能；免疫荧光染色和Western blot检测AD相关病理改变；激光共聚焦和Imairs软件观察并分析海马齿状回区神经元的树突棘形态变化；Western blot检测海马组织中突触相关蛋白的表达水平。结果：水迷宫实验中，与WT组的小鼠相比，NS和shRNA组小鼠到达平台的时间、到达平台的距离及第一次进入平台所在象限的时间均显著增加（P<0.05或P<0....     

亚甲蓝对APP/PS1转基因小鼠学习记忆及海马结构内GFAP表达的影响

目的:观察亚甲蓝对APP/PS1转基因小鼠学习记忆及胶质纤维酸性蛋白(Glial fibrillary acidic pro-tein,GFAP)在海马结构表达变化的影响。方法:20只3月龄APP/PS1小鼠,随机分2组,每组10只,对照组:自由饮水;治疗组:根据小鼠饮水量将亚甲蓝加入日常饮水中(25 mg/kg/d)连用4个月至7月龄。水迷宫测试观察其行为学的改变,免疫组化、Western Blot和TUNEL染色法观察GFAP在海马结构的表达及神经元的凋亡情况。结果:水迷宫测试结果显示亚甲蓝喂养组APP/PS1转基因小鼠第2～4 d的平均潜伏期显著低于对照组小鼠的潜伏期,说明治疗组与对照组相比在7个月时出现明显差异(P<0.05);免疫组化和Western结果显示治疗组海马结构内的GFAP在APP/PS1转基因小鼠的表达下调(P<0.05)。TUNEL染色法显示治疗组海马CA1、CA3区和齿状回TUNEL阳性细胞数较对照组明显减少(P<0.05)。结论:亚甲蓝能够下调APP/PS1小鼠海马结构内GFAP蛋白的表达,并通过抑制海马结构神经元的凋亡,提高APP/PS1小鼠的认知能力。     

Suvorexant通过调控PER1蛋白表达改善APP/PS1小鼠昼夜节律紊乱行为

目的:探讨orexin双受体拮抗剂suvorexant对9月龄APPswe/PS1dE9(APP/PS1)双转基因小鼠行为昼夜节律紊乱的影响及机制。方法:8月龄APP/PS1小鼠和具有同样遗传背景的野生型(WT)小鼠随机分为4组,在ZT0口服灌胃suvorexant或等体积溶剂28 d,采用跑轮行为学观察小鼠昼夜节律变化,免疫组织化学和Western Blot分别检测SCN脑区Aβ斑块和PER1蛋白的表达。结果:(1)在光暗交替环境中,给予suvorexant后APP/PS1小鼠相对振幅(P 0. 01)和鲁棒值(P 0. 01)明显升高,昼夜变异性明显降低(P 0. 01)。(2)在持续黑暗环境中给予suvorexant后,APP/PS1小鼠的自由运转周期明显缩短(P 0. 05),活动持续时间缩短(P 0. 01),相对振幅增大(P 0. 01),昼夜变异性减小(P 0. 01)。(3)免疫组化结果显示各组动物的SCN脑区未检测到Aβ阳性斑块。(4) APP/PS1小鼠给予Suvorexant后部分恢复了PER1蛋白表达的昼夜节律性。结论:suvorexant通过恢复SCN脑区PER1的昼夜节律性表达改善APPswe/PS1dE9小鼠的昼夜节律紊乱,增强其昼夜节律稳定性。     

丹酚酸B减轻骨关节炎模型大鼠软骨组织损伤

目的 探究丹酚酸B对骨关节炎模型大鼠的软骨组织损伤、低氧诱导因子-1(HIF-1)和血管内皮生长因子(VEGF)的影响。方法 构建骨关节炎模型大鼠，大鼠随机分为假手术组、骨关节炎组[切断交叉韧带法(ACLT)]、尼美舒利组、丹酚酸B高(40 mg/kg)和低(10 mg/kg)剂量组及丹酚酸B+HIF-1激活组，每组12只。显微CT机检测关节处骨结构；番红固绿染色和Masson染色观察软骨组织病理学变化；检测血清白介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)含量、诱导性一氧化氮合酶(iNOS)的活性；Western blot检测软骨组织HIF-1、VEGF、基质金属蛋白酶13(MMP-13)及活化的半胱氨酸天冬氨酸蛋白酶3(ceaved caspase-3)表达。结果 与假手术组相比，骨关节炎组软骨组织损伤严重，踝骨骨体积分数(BV/TV)降低，踝骨表面积与骨体积比值(BSA/BV)、血清中IL-6、TNF-α含量、iNOS活性、软骨HIF-1、VEGF、MMP-13及cleaved caspase-3蛋白表达升高(P<0.05);与骨关节炎组相比，尼美舒利组、丹酚酸B高...     

激活APP/PS1小鼠β_2-AR增强海马神经元再生并改善记忆缺失

目的:研究β_2-肾上腺素受体(β_2-AR)对阿尔茨海默病(AD)APP/PS1转基因小鼠海马神经元再生和学习记忆的作用。方法:12只AD小鼠随机分为APP/PS1组和APP/PS1+Clen组,另选6只野生型小鼠作为对照组(WT)。APP/PS1+Clen组于第8月龄起行腹腔注射β_2-AR激动剂Clenbuterol(Clen)2 mg/kg/d,持续2个月。APP/PS1组和WT组均接受等量的0.9%生理盐水稀释的DMSO。给药后对小鼠进行Morris水迷宫试验检测小鼠的学习记忆能力,后取脑切片进行PSA-NCAM免疫组织化学染色。结果:与APP/PS1组相比,APP/PS1+Clen组逃避潜伏期明显缩短,而目标象限停留时间及经过平台次数明显增加(P0.05)。免疫组织化学法显示APP/PS1+Clen组小鼠海马区PSA-NCAM表达增强。结论:通过Clenbuterol激活APP/PS1小鼠β_2-AR可增强海马神经元再生并改善记忆缺失。     

bFGF促进内源性神经干细胞增殖改善APP/PS1小鼠认知功能障碍

目的 探究bFGF对APP/PS1转基因小鼠海马内源性神经干细胞增殖及认知功能的影响.方法 将7月龄APP/PS1小鼠20只,随机分为模型组及bFGF组,每组10只;另取同龄C57BL/6小鼠作为对照组,连续鼻腔滴注给药4周,每天一次.TUNEL检测小鼠海马区神经细胞凋亡情况;免疫荧光染色检测小鼠海马区BrdU/Nes...     

Forskolin调节DHA对APP/PS1转基因小鼠突触可塑性和认知功能的增强作用

目的研究Forskolin调节DHA对APP/PS1转基因小鼠突触可塑性和认知功能的影响。方法对7月龄APP/PS1小鼠给予DHA及DHA和forskolin联合进行治疗。30d后,通过行为学试验检测其认知功能;通过组织病理学试验检测脑内细胞密度及脑突触形成能力和突触标记物Synaptophysin的表达以及通过Western blotting检测脑内pCREB1蛋白含量。结果 8月龄APP/PS1小鼠海马区面积、细胞密度、Synaptophysin和脑内pCREB1蛋白均明显降低,行为学上出现了明显的认知功能障碍。单独给予DHA以及DHA和forskolin联合给药治疗后,APP/PS1小鼠海马区面积、细胞密度、Synaptophysin和脑内pCREB1蛋白均增加,认知功能障碍得到改善,并且联合给药组的效果更为显著,但是均未恢复至生理水平。结论 DHA和forskolin联合治疗后,forskolin增强DHA对APP/PS1转基因小鼠突触病理和认知障碍的治疗作用。     

Pain and Effusion and Quadriceps Activation and Strength

Context:

Quadriceps dysfunction is a common consequence of knee joint injury and disease, yet its causes remain elusive.

Objective:

To determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion affect the magnitude of quadriceps dysfunction.

Design:

Crossover study.

Setting:

University research laboratory.

Patients or Other Participants:

Fourteen (8 men, 6 women; age = 23.6 ± 4.8 years, height = 170.3 ± 9.16 cm, mass = 72.9 ± 11.84 kg) healthy volunteers.

Intervention(s):

All participants were tested under 4 randomized conditions: normal knee, effused knee, painful knee, and effused and painful knee.

Main Outcome Measure(s):

Quadriceps strength (Nm/kg) and activation (central activation ratio) were assessed after each condition was induced.

Results:

Quadriceps strength and activation were highest under the normal knee condition and differed from the 3 experimental knee conditions (P < .05). No differences were noted among the 3 experimental knee conditions for either variable (P > .05).

Conclusions:

Both pain and effusion led to quadriceps dysfunction, but the interaction of the 2 stimuli did not increase the magnitude of the strength or activation deficits. Therefore, pain and effusion can be considered equally potent in eliciting quadriceps inhibition. Given that pain and effusion accompany numerous knee conditions, the prevalence of quadriceps dysfunction is likely high.Key Words: arthrogenic muscle inhibition, central activation failure, voluntary activation, muscles

Key Points

• Knee pain and effusion resulted in arthrogenic muscle inhibition and weakness of the quadriceps.
• The simultaneous presence of pain and effusion did not increase the magnitude of quadriceps dysfunction.
• To reduce arthrogenic muscle inhibition and improve muscle strength, clinicians should employ interventions that target removing both pain and effusion.

Quadriceps weakness is a common consequence of traumatic knee joint injury^1,2 and chronic degenerative knee joint conditions.^3,4 Arthrogenic muscle inhibition (AMI), a neurologic decline in muscle activation, results in quadriceps weakness and hinders rehabilitation by preventing gains in strength.⁵ The inability to reverse AMI and restore muscle function can lead to decreased physical abilities,⁶ biomechanical deficits,⁷ and possibly reinjury.⁵ Furthermore, researchers^8,9 have suggested that quadriceps weakness resulting from AMI may place patients at risk for developing osteoarthritis in the knee. In light of the substantial influence of quadriceps AMI on these clinically relevant outcomes, we need to improve our understanding of the factors that contribute to this neurologic decline in muscle activity so efforts to target and reverse it can be implemented and gains in strength can be achieved more easily.Joint injury and disease are accompanied by numerous sequelae (ie, pain, swelling, tissue damage, inflammation), so ascertaining which one ultimately leads to neurologic muscle dysfunction is difficult. Whereas a joint effusion can result in AMI,^10–12 the effects of pain are less understood despite many clinicians attributing AMI to pain. Using techniques that introduce knee pain without accompanying injury may provide insights into the role of pain in eliciting AMI.The degree of knee joint damage may play a role in the quantity of AMI that manifests. Hurley et al^13,14 demonstrated that quadriceps AMI, measured using an interpolated-twitch technique, was greater in patients with extensive traumatic knee injury (eg, fractured tibial plateau, ruptured medial collateral ligament, and medial meniscectomy) than patients with isolated joint trauma (ie, isolated anterior cruciate ligament [ACL] rupture). Similarly, patients with more knee joint symptoms (ie, greater number of symptoms and increased severity of symptoms) may present with greater magnitudes of quadriceps inhibition. Recently, investigators¹⁵ have suggested that patients with more pain display less quadriceps strength, supporting this tenet. Given that effusion and pain often present simultaneously with joint injuries and diseases, such as ACL injury and osteoarthritis, examining both the isolated and cumulative effects of these sequelae appears warranted to determine if they influence the magnitude of muscle inhibition.Experimental joint-effusion and pain models are safe and effective experimental methods that allow for the isolated examination of their effects on muscle function. The effusion model, whereby sterile saline is injected directly into the knee joint capsule,⁷ produces a clinically relevant magnitude of the joint effusion that may be present with traumatic injury. Effusion is thought to activate group II afferents responding to stretch or pressure,^16–18 which in turn may facilitate group Ib interneurons and result in quadriceps AMI.⁵ The pain model involves injecting hypertonic saline into the infrapatellar fat pad to produce anteromedial knee pain similar to that described in patients with patellofemoral pain syndrome.¹⁹ Pain is considered to initiate AMI through activation of group III and IV afferents that act as nocioceptors to signal damage or potential damage to joint structures.^16–18 The firing of these afferents then may lead to facilitation of group Ib interneurons, the flexion reflex, or the gamma loop, ultimately resulting in quadriceps inhibition.²⁰ Thus, these models allow us to create symptoms that are associated with knee injury and have the added benefit of providing a way to examine their effects in isolation.Therefore, the purpose of our study was to determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion would affect the magnitude of quadriceps dysfunction. We hypothesized that pain alone would result in quadriceps inhibition and that the magnitude of inhibition would be greater when effusion and pain were present simultaneously.     

即早基因c-fos与脑血管病及学习记忆

即早基因c-fos是广泛存在于原核细胞和真核细胞的高度保守基因.在正常情况下,c-fos基因参与细胞生长、分化、信息传递、学习和记忆等生理过程,而在病理情况下c-fos基因表达及调控变化与多种疾病的发生和发展有关.C-fos在中枢神经系统的某些部位可有基础水平的表达,但表达很低,当受到如脑缺血、脑出血、痫性发作、应激等刺激后,其在数十分钟内做出反应,在对外界刺激-转录耦联的信忠传递过程中起着核内第三信使的重要作用.     

Opportunities and challenges in the prevention and control of cancer and other chronic diseases: children's diet and nutrition and weight and physical activity

OBJECTIVE: The purpose of this article is to review the role of behavioral research in disease prevention and control, with a particular emphasis on lifestyle- and behavior-related cancer and chronic disease risk factors--specifically, relationships among diet and nutrition and weight and physical activity with adult cancer, and tracking developmental origins of these health-promoting and health-compromising behaviors from childhood into adulthood. METHOD: After reviewing the background of the field of cancer prevention and control and establishing plausibility for the role of child health behavior in adult cancer risk, studies selected from the pediatric published literature are reviewed. Articles were retrieved, selected, and summarized to illustrate that results from separate but related fields of study are combinable to yield insights into the prevention and control of cancer and other chronic diseases in adulthood through the conduct of nonintervention and intervention research with children in clinical, public health, and other contexts. RESULTS: As illustrated by the evidence presented in this review, there are numerous reasons (biological, psychological, and social), opportunities (school and community, health care, and family settings), and approaches (nonintervention and intervention) to understand and impact behavior change in children's diet and nutrition and weight and physical activity. CONCLUSIONS: Further development and evaluation of behavioral science intervention protocols conducted with children are necessary to understand the efficacy of these approaches and their public health impact on proximal and distal cancer, cancer-related, and chronic disease outcomes before diffusion. It is clear that more attention should be paid to early life and early developmental phases in cancer prevention.