• 제목/요약/키워드: Brain mechanisms

검색결과 489건 처리시간 0.039초

A Neuroprotective Action of Quercetin and Apigenin through Inhibiting Aggregation of Aβ and Activation of TRKB Signaling in a Cellular Experiment

  • Ya-Jen Chiu;Yu-Shan Teng;Chiung-Mei Chen;Ying-Chieh Sun;Hsiu Mei Hsieh-Li;Kuo-Hsuan Chang;Guey-Jen Lee-Chen
    • Biomolecules & Therapeutics
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    • 제31권3호
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    • pp.285-297
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    • 2023
  • Alzheimer's disease (AD) is a neurodegenerative disease with progressive memory loss and the cognitive decline. AD is mainly caused by abnormal accumulation of misfolded amyloid β (Aβ), which leads to neurodegeneration via a number of possible mechanisms such as down-regulation of brain-derived neurotrophic factor-tropomyosin-related kinase B (BDNF-TRKB) signaling pathway. 7,8-Dihydroxyflavone (7,8-DHF), a TRKB agonist, has demonstrated potential to enhance BDNF-TRKB pathway in various neurodegenerative diseases. To expand the capacity of flavones as TRKB agonists, two natural flavones quercetin and apigenin, were evaluated. With tryptophan fluorescence quenching assay, we illustrated the direct interaction between quercetin/apigenin and TRKB extracellular domain. Employing Aβ folding reporter SH-SY5Y cells, we showed that quercetin and apigenin reduced Aβ-aggregation, oxidative stress, caspase-1 and acetylcholinesterase activities, as well as improved the neurite outgrowth. Treatments with quercetin and apigenin increased TRKB Tyr516 and Tyr817 and downstream cAMP-response-element binding protein (CREB) Ser133 to activate transcription of BDNF and BCL2 apoptosis regulator (BCL2), as well as reduced the expression of pro-apoptotic BCL2 associated X protein (BAX). Knockdown of TRKB counteracted the improvement of neurite outgrowth by quercetin and apigenin. Our results demonstrate that quercetin and apigenin are to work likely as a direct agonist on TRKB for their neuroprotective action, strengthening the therapeutic potential of quercetin and apigenin in treating AD.

Neuroprotective Effect of Aloesin in a Rat Model of Focal Cerebral Ischemia

  • K.J. Jung;Lee, M.J.;E.Y. Cho;Y.S. Song;Lee, Y.H.;Park, Y.L.;Lee, Y.S.;C. Jin
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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    • pp.62-62
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    • 2003
  • It is now convincing that free radical generation is involved in the pathophy siological mechanisms of ischemic stroke, particularly in ischemia-reperfusion injury. The present study, therefore, examined neuroprotective effect of aloesin isolated from Aloe vera, which was known to have antioxidative activity, in a rat model of transient focal cerebral ischemia. Transient focal cerebral ischemia was induced by occlusion of middle cerebral artery for 2 hr with a silicone-coated 4-0 nylon monofilament in male Sprague-Dawley rats under isoflurane anesthesia Aloesin (1, 3, 10, 30 and 50 mg/kg/injection) was administered intravenously 3 times at 0.5, 2 and 4 hr after onset of ischemia. Neurological score was measured 24 hr after onset of ischemia immediately before sacrifice. Seven serial coronal slices of the brain were stained with 2,3,5-triphenyltetrazolium chloride and infarct size was measured using a computerized image analyzer. Treatment with the close of 1 or 50 mg/kg did not significantly reduce infarct volume compared with the saline vehicle-treated control group. However, treatments with the closes of 3 and 10 mg/kg significantly reduced both infarct volume and edema by approximately 47% compared with the control group, producing remarkable behavioral recovery effect. Treatment with the close of 30 mg/kg also significantly reduced infarct volume to a lesser extent by approximately 33% compared with the control group, but produced similar degree of behavioral recovery effect. In addition, general pharmacological studies showed that aloesin was a quite safe compound. The results suggest that aloesin can serve as a lead chemical for the development of neuroprotective agents by providing neuroprotection against focal ischemic neuronal injury.

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α-Pinene Attenuates Methamphetamine-Induced Conditioned Place Preference in C57BL/6 Mice

  • Chan Lee;Jung-Hee Jang;Gyu Hwan Park
    • Biomolecules & Therapeutics
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    • 제31권4호
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    • pp.411-416
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    • 2023
  • Methamphetamine (METH) is a powerful neurotoxic psychostimulant affecting dopamine transporter (DAT) activity and leading to continuous excess extracellular dopamine levels. Despite recent advances in the knowledge on neurobiological mechanisms underlying METH abuse, there are few effective pharmacotherapies to prevent METH abuse leading to brain damage and neuropsychiatric deficits. α-Pinene (APN) is one of the major monoterpenes derived from pine essential oils and has diverse biological properties including anti-nociceptive, anti-anxiolytic, antioxidant, and anti-inflammatory actions. In the present study, we investigated the therapeutic potential of APN in a METH abuse mice model. METH (1 mg/kg/day, i.p.) was injected into C57BL/6 mice for four alternative days, and a conditioned place preference (CPP) test was performed. The METH-administered group exhibited increased sensitivity to place preference and significantly decreased levels of dopamine-related markers such as dopamine 2 receptor (D2R) and tyrosine hydroxylase in the striatum of the mice. Moreover, METH caused apoptotic cell death by induction of inflammation and oxidative stress. Conversely, APN treatment (3 and 10 mg/kg, i.p.) significantly reduced METH-mediated place preference and restored the levels of D2R and tyrosine hydroxylase in the striatum. APN increased the anti-apoptotic Bcl-2 to pro-apoptotic Bax ratio and decreased the expression of inflammatory protein Iba-1. METH-induced lipid peroxidation was effectively mitigated by APN by up-regulation of antioxidant enzymes such as manganese-superoxide dismutase and glutamylcysteine synthase via activation of nuclear factor-erythroid 2-related factor 2. These results suggest that APN may have protective potential and be considered as a promising therapeutic agent for METH-induced drug addiction and neuronal damage.

The Effect of Treadmill Exercise on Tau Hyperphosphorylayion in an Aged Transgenic Mouse Model of Taupathies

  • Wang, Seong-Hwan;Kang, Eun-Bum;Kwon, In-Su;Koo, Jung-Hoon;Shin, Kwang-O;Jang, Yong-Chul;Um, Hyun-Sub;Oh, Yoo-Sung;Kim, Chul-Hyun;Cho, In-Ho;Cho, Joon-Yong
    • 운동영양학회지
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    • 제16권2호
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    • pp.93-100
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    • 2012
  • Alzheimer's disease (AD) is the most common cause of dementia in adults. Microtubule associated protein tau is abnormally phosphorylated in AD and aggregates as paired helical filaments (PHFs) in neurofibrillary tangles (NFTs). NFTs are the most common intraneuronal inclusion in the brains of patients with AD and have been implicated in mediating neuronal cell death and cognitive deficit. Aberrant phosphorylation of tau is an early pathological event in AD, but the underlying mechanisms are unclear. MAP kinases are a family of Serine/Threonine (Ser/Thr) kinases that involved hyper - phosphorylation of tau in AD. The purpose of this study was to investigate the effect of treadmill exercise on phosphorylation of tau level and activation of MAPKs including JNK, ERK, p38-MAPK. To address this, Tg mouse model of AD, Tg-NSE/hTau 23, which expresses human tau 23 in the brain, was chosen. Animals were subjected to treadmill exercise for 12 weeks from 24 months of age. Treadmill exercise in Tg group improved cognitive function compared with Tg-SED group in watermaze test. In addition, treadmill exercised Tg mice significantly reduced the activation of JNK54/46, p38-MAPK and tau (Ser404, Ser202, Thr231), and increased activation of ERK44/42 in cerebral cortex. These results suggest that treadmill exercise may provide a therapeutic potential to alleviate the tau pathology like AD.

신뢰와 건강 (Trust and Health: Mind-Body Problem or Integrative Medicine)

  • 손정락
    • 한국심리학회지 : 문화 및 사회문제
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    • 제11권spc호
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    • pp.85-95
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    • 2005
  • 신뢰가 건강에 관련되는 기제를 정신-신체 의학 또는 통합의학적인 관점에서 살펴보았다. 이를 위해 양자물리학, 심신의학 및 동양의 치유방법 등의 연구성과를 알아보고 건강과 행복을 추구하는 방법도 제시하였다. 먼저, 콴툼 구조적인 사람의 몸에 관한 절에서는, 신체에는 그 자신의 정신이 있다는 연구 결과들을 알아보았는데, 여기서는 질병의 메커니즘과 원인, 의식의 객관적인 경험으로서의 몸, 의식과 정보에 영향 받는 몸 등을 다루었다. 그 다음에, 심신의학의 연구결과들을 다루었는데, 여기서는 뇌를 변화시키는 생각, 플라시보와 기대의 힘, 적극적인 노력으로 성취되는 건강, 심리신경면역학 및 치료방법들을 알아보았다. 끝으로, 몸과 마음의 행복을 위한 Benson의 실천방법을 알아보았는데, 병에서 회복하고 건강해지는데는 신념(자신에 대한 신념, 의사에 대한 신념, 치료에 대한 신념 및 자신의 영적인 신념)이 무엇보다도 중요하다는 결론에 이르렀다.

Raw Inonotus obliquus polysaccharide counteracts Alzheimer's disease in a transgenic mouse model by activating the ubiquitin-proteosome system

  • Shumin Wang;Kaiye Dong;Ji Zhang;Chaochao Chen;Hongyan Shuai;Xin Yu
    • Nutrition Research and Practice
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    • 제17권6호
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    • pp.1128-1142
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    • 2023
  • BACKGROUND/OBJECTIVES: Inonotus obliquus has been used as antidiabetic herb around the world, especially in the Russian and Scandinavian countries. Diabetes is widely believed to be a key factor in Alzheimer's disease (AD), which is widely considered to be type III diabetes. To investigate whether I. obliquus can also ameliorate AD, it would be interesting to identify new clues for AD treatment. We tested the anti-AD effects of raw Inonotus obliquus polysaccharide (IOP) in a mouse model of AD (3×Tg-AD transgenic mice). MATERIALS/METHODS: SPF-grade 3×Tg-AD mice were randomly divided into three groups (Control, Metformin, and raw IOP groups, n = 5 per group). β-Amyloid deposition in the brain was analyzed using immunohistochemistry for AD characterization. Gene and protein expression of pertinent factors of the ubiquitin-proteasome system (UPS) was determined using real-time quantitative polymerase chain reaction and Western blotting. RESULTS: Raw IOP significantly reduced the accumulation of amyloid aggregates and facilitated UPS activity, resulting in a significant reduction in AD-related symptoms in an AD mouse model. The presence of raw IOP significantly enhanced the expression of ubiquitin, E1, and Parkin (E3) at both the mRNA and protein levels in the mouse hippocampus. The mRNA level of ubiquitin carboxyl-terminal hydrolase isozyme L1, a key factor involved in UPS activation, also increased by approximately 50%. CONCLUSIONS: Raw IOP could contribute to AD amelioration via the UPS pathway, which could be considered as a new potential strategy for AD treatment, although we could not exclude other mechanisms involved in counteracting AD processing.

비즈니스 문제 해결 창의성에 미치는 감정의 영향에 관한 EEG 기반 탐색연구 (EEG-Based Explorative Study of the Role of Emotions on Business Problem-solving Creativity)

  • ;이건창
    • 경영정보학연구
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    • 제22권3호
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    • pp.1-14
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    • 2020
  • 본 연구는 신경생리학적 분석의 관점에서 창의성의 기존 문헌에 공헌하는 것을 목표로 한다. 특히 감정이 비즈니스 문제 해결 창의성(BPSC: Business Problem-Solving Creativity)에 어느 정도의 영향을 미치는지를 뇌파(EEG) 분석을 통하여 살펴보았다. 본 연구에서 적용한 실험에서는 실험참가자로 하여금 경영정보분야에서 널리 사용되는 인지지도(cognitive map)에 기반한 비즈니스 문제를 해결하도록 하고 그 결과를 평가함으로써 비즈니스 문제해결 창의성을 측정하였다. 총 34명의 참가자를 대상으로 하였고 EEG 분석을 통해 실험자료를 분석한 결과 긍정적인 감정에서보다 부정적인 감정하에서 비즈니스 문제해결 창의성이 통계적으로 유의미하게 증가하는 것을 확인할 수 있었다. 본 연구는 경영정보분야 의사결정기법을 적용한 BPSC를 뇌파분석을 통하여 실증적으로 분석할 수 있음을 보여주었다는 면에서 기존연구에 기여한다.

TCF4-Targeting miR-124 is Differentially Expressed amongst Dendritic Cell Subsets

  • Sun Murray Han;Hye Young Na;Onju Ham;Wanho Choi;Moah Sohn;Seul Hye Ryu;Hyunju In;Ki-Chul Hwang;Chae Gyu Park
    • IMMUNE NETWORK
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    • 제16권1호
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    • pp.61-74
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    • 2016
  • Dendritic cells (DCs) are professional antigen-presenting cells that sample their environment and present antigens to naïve T lymphocytes for the subsequent antigen-specific immune responses. DCs exist in a range of distinct subpopulations including plasmacytoid DCs (pDCs) and classical DCs (cDCs), with the latter consisting of the cDC1 and cDC2 lineages. Although the roles of DC-specific transcription factors across the DC subsets have become understood, the posttranscriptional mechanisms that regulate DC development are yet to be elucidated. MicroRNAs (miRNAs) are pivotal posttranscriptional regulators of gene expression in a myriad of biological processes, but their contribution to the immune system is just beginning to surface. In this study, our in-house probe collection was screened to identify miRNAs possibly involved in DC development and function by targeting the transcripts of relevant mouse transcription factors. Examination of DC subsets from the culture of mouse bone marrow with Flt3 ligand identified high expression of miR-124 which was able to target the transcript of TCF4, a transcription factor critical for the development and homeostasis of pDCs. Further expression profiling of mouse DC subsets isolated from in vitro culture as well as via ex vivo purification demonstrated that miR-124 was outstandingly expressed in CD24+ cDC1 cells compared to in pDCs and CD172α+ cDC2 cells. These results imply that miR-124 is likely involved in the processes of DC subset development by posttranscriptional regulation of a transcription factor(s).

SK-N-SH 신경세포내 항산화 효과와 p38 인산화 억제에 의한 곤드레, 누룩치 그리고 산마늘의 신경 보호 효과 (Neuroprotective Effects of Cirsium setidens, Pleurospermum kamtschaticumin, and Allium victorials Based on Antioxidant and p38 Phosphorylation Inhibitory Activities in SK-N-SH Neuronal Cells)

  • 정미자;박용일;권기한
    • 한국식품영양과학회지
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    • 제44권3호
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    • pp.347-355
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    • 2015
  • 신경계 질환은 산화적 스트레스에 의한 신경세포 손상에 의해 발생하는 것이 하나의 기전으로 알려져 있다. 본 연구는 $H_2O_2$에 의해 유도된 산화적 스트레스에 대항하여 곤드레(Cirsium setidens, CS), 누룩치(Pleurospermum kamtschaticumin, PK) 그리고 산마늘(Allium victorials, AV)의 뇌신경 보호 효과 및 그 기전에 대한 것이다. CS와 AV 처리는 대조군과 비교하여 $400{\mu}g/mL$까지 인간의 신경세포주인 SK-N-SH 세포에 대해 세포독성이 없었다. 산화적 유도자인 $H_2O_2$를 SK-N-SH 세포에 처리하였을 때 세포사멸 및 활성산소종(ROS) 생산이 현저하게 증가하였으나 CS 또는 AV 처리에 의해 산화적 스트레스에 의해 증가된 세포사멸과 ROS 생산이 현저하게 감소하였다. 실험한 산채 중에 CS와 PK가 AV보다 더 강한 DPPH 라디칼 소거 작용이 있었으나 PK는 대조군과 비교하여 SK-N-SH 세포를 사멸시키는 강한 세포독성을 가지고 있었다. CS는 AV보다 산화적 스트레스에 대항하여 세포사멸 및 ROS 생성에 더 높은 저해적 영향력을 보여주었다. 따라서 계속되는 실험에는 CS를 사용하였다. CS의 순차적 용매 분획물들인 헥산, 클로로포름, 에틸아세테이트, 부탄올 및 물 분획물들(CS-HE, CS-CH, CS-EA, CS-BU, CS-AQ)은 산화적 스트레스에 대항하여 SK-N-SH 세포사멸 및 세포내 ROS 생성을 억제하였다. CS-EA는 5개의 분획물들 중 가장 강한 DPPH 라디칼 소거작용 및 세포내 ROS 소거 활성을 가지고 있었고, 가장 강한 뇌신경세포 보호 효과를 가지고 있었다. CS-EA는 산화적 스트레스에 의해 증가된 세포자멸사(apoptosis)의 신호전달 경로에 관여하는 p38의 인산화를 저해함으로써 활성화되는 것을 약화시켰다. 이 결과들은 CS-EA가 뇌신경세포에서 항산화 효과 및 p38 인산화 억제에 의한 뇌신경 보호 효과를 나타낼 것이라 제안하였다.

교모세포종 세포주 U-87에서 세포내 PKC 농도와 종양침습성과의 상관 관계 (The Relationship between Intracellular Protein Kinase C Concentration and Invasiveness in U-87 Malignant Glioma Cells)

  • 지철;조경근;이경진;박성찬;조정기;강준기;최창락
    • Journal of Korean Neurosurgical Society
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    • 제30권3호
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    • pp.263-271
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    • 2001
  • 교모세포종은 비교적 흔한 원발성 뇌종양이며 생물학적 특성상 빠른 성장률을 보이는 것 외에 침습성이 강하여 종양과 인접한 부분을 파괴 시킬 뿐 아니라 직접접촉하지 않는 부분의 파괴도 일어나게 되어 그 결과 치료 예후가 매우 불량한 것으로 되어 있다. 이러한 불량한 예후를 개선 시키기 위해서는 이들 종양의 침습에 대한 기전의 정확한 이해가 필요하며 이를 이용한 새로운 치료방법이 요구된다할 것이다. Protein kinase C(PKC)는 세포내 신호전달체제 과정에서 매우 중요한 역할을 하는 효소로 세포막 수용체 신호를 핵으로 전달하는 역할을 하며 세포내 여러 생물학적 작용이 알려져 있다. 본 실험은 종양침습과 연관하여 세포내 PKC가 어떠한 작용을 하는지에 대해서 악성교종 세포를 대상으로 하여 알아보고자 하였다. 따라서 PKC가 종양침습에 중요한 역할을 할 것이라는 가설을 세웠고 이 가설을 증명하기 위해 세포내 PKC농도를 길항제 및 촉진제를 이용하며 높고 낮게 조절함으로써 그에 따른 침습성의 변화를 살펴보았다. 방법으로는 교모세포종 세포주인 U-87 세포를 약제로 처리한 후 인위적으로 조절된 세포내의 PKC에 대해 효소의 활성도를 측정하였고 침습성은 matrigel artificial basement membrane assay 및 tumor spheroid fetal rat brain aggregate(FRBA) confrontation assay를 이용하여 측정하였다. 결과로 PKC의 길항제인 tamoxifen과 hypericin으로 처치한 세포는 PKC의 활성과 침습도가 모두 감소하였으며 이는 약제농도에 비례하여 나타났다. 반면 PKC 자극제인 TPA로 처치된 세포는 증가된 PKC 활성도나 침습도을 보이지 않았다. 이러한 결과를 종합해 보았을 때 PKC는 종양세포의 침습성에 중요한 역할을 함을 알 수 있었으며 PKC의 길항제는 종양 치료에 유용한 화학 요법 제가 될 수 있을 것으로 사료된다.

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