Troponin is a complex of three calcium-regulative proteins - troponin C, troponin I, and troponin T. These proteins are distributed along the entire length of thin filaments and forms an ordered complex with tropomyosin and actin. All of which are integral to muscle contraction, for the heart, muscle fibers, and skeleton.
Its main purpose and benefit are to detect diagnostic and prognostic issues, such as myocardial infarction. When the body displays high troponin levels, this signals to a doctor that there is cardiac muscle cell death occurring, which is where the enzyme is released into the blood upon injury to the heart.
Troponin is formed of three subunits, which govern skeletal and cardiac muscle contraction. The three subunits include:
● Troponin I/TNNI (TnI): the protein subunit that inhibits muscle contraction in the absence of calcium.
● Troponin T/TNNT (TnT): anchors the troponin complex to the muscle fiber structure.
● Troponin C (TnC): binds to calcium ions to produce a conformational change in TnI.
Troponin interactions occur due to heart problems such as myocarditis (heart inflammation), weakening of the heart (cardiomyopathy), congestive heart failure, or infections. When troponin levels are elevated, heart injury and disease can occur.
Troponin levels can increase from stress. People with heart disease who experience mental stress induced-ischemia tend to have higher levels of troponin. These can reduce in time, typically over a few days.