腫瘍死滅因子-αは,圧力過負荷状態後の心臓の改造と心室機能不全を媒介する
Mei Sun1, Manyin Chen, Fayez Dawood
1The Heart and Stroke/Richard Lewar Centre of Excellence and Toronto General University Health Network, Toronto, Ontario, Canada.
Circulation
|March 14, 2007
まとめ
腫瘍死滅因子アルファ (TNF-alpha) は,圧力過負荷に伴う不良心改造と機能不全を誘発する. マウスにおけるTNF-αを阻害すると,心筋縮,炎症を軽減し,心臓の機能が改善された.
科学分野:
- 心血管生物学 心血管生物学
- 分子心臓病学 分子心臓病学
- 心臓病理生理学 心臓病理生理学
背景:
- 圧力過負荷は心筋細胞のアポトーシス,高縮,炎症を引き起こし,心不全を引き起こす.
- 腫瘍死滅因子アルファ (TNF-alpha) は,圧力の過負荷の後,心筋で上調されます.
- 機械的ストレスに対する心臓の反応を調節するTNF-αの正確な役割は,完全に理解されていません.
研究 の 目的:
- 心臓の炎症反応の調節,細胞外マトリックスホメオスタシス,圧力過負荷下における高縮のTNF-αの役割を調査する.
- TNF-αが,機械的過負荷によって誘発される心室機能不全に寄与するかどうかを判断する.
主な方法:
- C57/BLワイルドタイプとTNFノックアウトのマウスを使用し,下降性大動脈帯または偽手術を受けた.
- 心臓のTNF-αレベル,筋細胞アポトシス,高縮,炎症マーカー,マトリックスメタルプロテインアゼ-9活性,心臓機能の評価.
- 野生型マウスとTNFノックアウトマウスの対照的アウトカム.
主要な成果:
- 大動脈帯は,野生型のマウスの心臓のTNF-α,ミオサイトアポトーシス,高縮,炎症を著しく増加させた.
- 野生型のマウスは,マトリックスメタルプロテインーゼ-9の活性が上昇し,バンド付け後,心臓機能が低下した.
- TNFノックアウトマウスは,心臓のアポトーシス,高縮,炎症,線維症が弱まり,心臓機能が改善され,MMP-9の活性が低下した.
結論:
- TNF-αは,圧力過負荷の際に有害な左心室改造を媒介する上で重要な役割を果たします.
- この研究は,TNF-αが心臓の修復と再構築プロセスを調節し,心室機能不全に貢献することを示唆しています.
- TNF-αを標的にすることは,圧力過負荷に起因する心不全の治療戦略を提供することができる.
関連する概念動画
Pathophysiology of Heart Failure
Heart failure (HF) is a progressive syndrome involving ventricles that leads to inadequate cardiac output. It can be classified based on location and output or ejection fraction. Ejection fraction (EF) is an essential measurement in the diagnosis and surveillance of HF. Reduced EF corresponds to systolic heart failure (HFrEF). However, HF with preserved ejection fraction (HFpEF) is becoming increasingly prevalent. Also known as diastolic HF, this form of HF is related to aging. The...
Imbalances in Cardiac Output
The heart's primary function is to pump blood throughout the body, maintaining a balance between blood sent out (cardiac output) and blood returning (venous return). If this balance is disrupted, it can result in congestive heart failure (CHF), a severe condition where the heart becomes an inefficient pump, leading to inadequate blood circulation.
CHF can occur due to the failure of either side of the heart. Left-side failure leads to pulmonary congestion—the right side continues to send blood...
CHF can occur due to the failure of either side of the heart. Left-side failure leads to pulmonary congestion—the right side continues to send blood...
Aortic Regurgitation I: Introduction
IntroductionAortic regurgitation is characterized by the backward flow of blood from the aorta into the left ventricle during diastole and arises from the improper closure of the aortic valve. This condition results in left ventricular volume overload and can stem from both acute and chronic etiologies, each contributing uniquely to the disease's progression and symptomatology.Acute and Chronic CausesAcute aortic regurgitation often results from events that suddenly impair the integrity of the...
Myocarditis I: Introduction
Myocarditis is inflammation of the myocardium, which is the muscular layer of the heart.EtiologyMyocarditis has a diverse etiology, including a wide range of infectious and non-infectious causes:Infectious CausesViral: Common viruses include Coxsackie A and B, adenovirus, parvovirus B19, enteroviruses, and influenza A.Bacterial: Examples include infections caused by Streptococcus, Staphylococcus, and Mycoplasma species.Rickettsial: Infections like Rocky Mountain spotted fever can result in...
Heart Failure I: Introduction
Heart failure refers to a clinical syndrome caused by structural or functional cardiac disorders that prevent the heart from pumping an adequate amount of blood to meet the body's metabolic needs. This condition often arises from myocardial infarction or ischemia, leading to decreased cardiac output, reduced tissue perfusion, impaired gas exchange, fluid volume imbalance, and decreased functional ability.Heart failure can result from disruptions in the mechanisms that regulate cardiac output...
Heart Failure II: Pathophysiology
Systolic Heart Failure and Compensatory MechanismsSystolic heart failure (also termed HFrEF, Heart Failure with Reduced Ejection Fraction) is the most prevalent type of heart filure. It results in a decreased volume of blood being pumped from the ventricle. The aortic arch and carotid sinuses have baroreceptors that detect reduced blood pressure, triggering the sympathetic nervous system (SNS) to release epinephrine and norepinephrine. Initially, this response aims to boost heart rate and...


