New Delhi, Sep 9: Lower levels of serotransferrin, a blood protein responsible for transporting iron in the body, could serve as an early indicator of coronary artery disease (CAD), potentially enabling detection before routine clinical diagnosis, scientists have found.
Researchers at the CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Delhi, analysed blood serum proteins and identified a significant association between reduced serotransferrin levels and CAD.
“Serotransferrin may have value as an early diagnostic marker, meaning it could potentially help identify CAD earlier than routine clinical diagnosis,” Sagarika Biswas, corresponding author of the study, told PTI.
CAD is a common cardiovascular condition in which the coronary arteries narrow due to atherosclerosis, primarily caused by the buildup of plaque or fatty deposits. Iron deficiency is also frequently observed among CAD patients.
The study, published in the journal Acta Cardiologica, analysed 197 differentially expressed proteins and found that serotransferrin (TF) was significantly downregulated in CAD patients compared with healthy individuals.
The researchers said understanding the molecular and cellular processes associated with serotransferrin could provide insights into how CAD develops and potentially help identify new diagnostic and therapeutic targets.
The study involved 50 CAD patients and 40 healthy individuals. It also found elevated levels of cardiac marker troponin I among CAD patients, with an inverse relationship between troponin I and serotransferrin levels.
Troponin I is a protein found in heart muscle cells. When the heart muscle is damaged, the protein enters the bloodstream and can be detected through blood tests.
“TF protein was significantly associated with CAD progression and inversely correlated with cTnI, suggesting it could be a potential therapeutic target pending further molecular and clinical investigation,” the researchers said.
Biswas said longitudinal studies would be needed to determine how many years in advance serotransferrin levels could help identify CAD.
The researchers linked reduced serotransferrin levels to the inflammatory environment caused by damage to the inner lining of arteries, which triggers an immune response against accumulated fatty deposits.
Biswas explained that worsening ischaemia and tissue injury can increase troponin I levels, while inflammatory and metabolic stress may suppress serotransferrin expression or availability in CAD.
Serotransferrin levels may also provide an indication of an individual's iron status. Biswas noted that, in standard iron studies, transferrin saturation below 20 per cent is commonly considered evidence of iron deficiency.
Transferrin is a family of iron-binding proteins, while serotransferrin is a form found in blood serum and plasma. The protein transports iron by binding to it through specific binding sites.
Biswas said lower serotransferrin levels indicate reduced iron-binding and transport capacity and may contribute to the functional iron deficiency associated with CAD. However, she clarified that the study did not quantify its contribution as a percentage.
