The role of IL-6, and IL-12+p40 in Ischemic heart disease patients
Authors: Al-Roubaey Dina , Sarhan Nadia Habeeb , AL-Salami Eman Hasani , Najeeb Ibtihal Riyadh , Idreess Hawraa Ghaleb 
Published: June 2023

Background: Ischemic heart disease (IHD)  is often termed coronary artery disease  or coronary heart disease; because it is usually caused by atherosclerosis that occurs when fatty materials and a substance called a plaque are built up on the walls of coronary arteries. Such consequences lead to a narrowing of these arteries and then blood flow can slow down or stop, causing chest pain, shortness of breath, heart attack and other related symptoms.

Objectives: To investigate the correlation between Ischemic heart disease and patient’s descriptive data such as gender, age, and to evaluate the role of two cytokines  IL-6 and  IL-12+p40 in the aetiology of IHD, as well as to observe the relationship of IL-6 , IL-12+p40  and  two related diseases diabetes mellitus and hypertension in IHD patients.

Methodology: A total of 70 (55 males and 15 females) patients with ischemic heart disease (IHD; stable angina) were included in the study. They were admitted to the Coronary Care Unit (CCU) at Ibn-Al-Betar Hospital (Baghdad) for a surgical operation during the period July 2022 - April 2023. The diagnosis was made by the consultant medical staff at the hospital. In addition to the patients, a total of 20 apparently healthy individuals (control group), with no history of cardiovascular diseases, were included in the study for the purpose of comparison with patients, they were age- and gender matched with patients. five ml of peripheral blood were obtained by venipuncture from each patient before surgical operation using 5 ml disposable syringe, the blood was drawn in a plain tube (without anti-coagulant).  Serum levels of  IL-6 and IL-12+p40 were quantitatively determined in patients and control subjects by means of indirect sandwich ELISA test.

Results: Thirty patients from total IHD patients were observed to have diabetic mellitus, and the frequency in males was more than in females (73.3 vs. 26.7%), twenty two IHD patients were observed to have hypertension in percentage higher in males than in females (77.3 vs. 22.7%). The results obtained from this study about age group distributions of IHD patients with  diabetic are higher in 60 and more age group in percentage (63.3%) , as well as in hypertensive patients in percentage (68.2%). Serum levels of IL-6 for total patients  are (404.8 pg/ml), diabetic (480.3 pg/ml), non-diabetic (250.8 pg/ml), hypertensive (451.6 pg/ml) and non-hypertensive (322.2 pg/ml), patients showed a significant increased serum level of IL-6 as compared to controls (155.7 pg/ml). The diabetic patients also showed a significantly higher level than non-diabetic patients (480.3 vs. 250.8 pg/ml), as well as, hypertensive patients (451.6 pg/ml) versus non-hypertensive patients (322.2 pg/ml). Serum level of IL-12+p40 for total patients (410.2 pg/ml), diabetic (357.7 pg/ml), non-diabetic (458.1 pg/ml), hypertensive (270 pg/ml) and non-hypertensive (420.5 pg/ml) patients showed a significant decreased level of IL-12+p40 as compared to controls (649.3 pg/ml). In contrast, the non-diabetic patients showed a significantly higher level than diabetic patients (458.1 vs. 357.7 pg/ml), as well as, non-hypertensive patients (420.5 pg/ml) versus hypertensive patients (270.0 pg/ml).

Conclusion: The prevalence of IHD according to age are increased in older aged patients, the male show high infected percentage than female. Chronic diseases like hypertension and diabetes mellitus were contributed to the pathogenesis of IHD, and proinflammatory cytokine cascades play crucial roles in the onset and progression of IHD.

Recommendations: Targeting cytokines in an attempt to develop pharmacological activators of some interleukins, and inhibitors of other ones, and this may provide effective means to control atherosclerosis and associated diseases (i.e. diabetes mellitus and hypertension).

Keywords: IL-6, IL-12+p40, IHD