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Updated: Feb 23, 2026
Improved Rodent Model of Myocardial Ischemia and Reperfusion Injury
Published on: March 7, 2022
Thyroid hormones decrease the proinflammatory TLR4/NF-κβ pathway and improve functional parameters of the left
Alexandre Luz de Castro1, Rafael Oliveira Fernandes2, Vanessa D Ortiz2
1Laboratory of Cardiovascular Physiology and Reactive Oxygen Species, Physiology Department, Institute of Basic Health Science (ICBS), Federal University of Rio Grande do Sul (UFRGS), Sarmento Leite Street, 500, CEP 90050-170, Porto Alegre, RS, Brazil; Centro Universitário Ritter dos Reis (Uniritter), Orfanotrófio Street, 555, CEP 90840-440, Porto Alegre, Rio Grande do Sul, Brazil.
Thyroid hormones (TH) reduce inflammation and oxidative stress in hearts after myocardial infarction. This anti-inflammatory action improves cardiac function, highlighting TH
Area of Science:
- Cardiology
- Endocrinology
- Molecular Biology
Background:
- Myocardial infarction (MI) induces oxidative stress and activates the TLR4/NF-κβ inflammatory pathway.
- Thyroid hormones (TH) are recognized for their cardioprotective effects post-MI.
- The impact of TH on the TLR4/NF-κβ pathway in the infarcted heart remains uninvestigated.
Purpose of the Study:
- To investigate the effect of thyroid hormones on the TLR4/NF-κβ pathway following myocardial infarction.
- To determine if TH modulate inflammatory responses and oxidative stress markers in the infarcted heart.
Main Methods:
- Male Wistar rats were divided into Sham-operated (SHAM), Sham+TH (SHAMT), Myocardial Infarction (AMI), and MI+TH (AMIT) groups.
- TH (T4 and T3) were administered orally for 12 days.
- Cardiac function was assessed via echocardiography, followed by biochemical and molecular analyses of left ventricular tissue.
Main Results:
- Thyroid hormones significantly modulated TLR4/NF-κβ expression in infarcted rat hearts.
- TH treatment led to a decrease in xanthine oxidase expression.
- These molecular changes correlated with improved cardiac function after infarction.
Conclusions:
- Thyroid hormones exert cardioprotective effects post-myocardial infarction.
- The beneficial actions of TH involve the modulation of the TLR4/NF-κβ inflammatory pathway.
- TH demonstrate anti-inflammatory properties that contribute to cardiac recovery after infarction.
