Associations of surfactant protein SP-A and SP-D content with blood lipid parameters in men and women of Novosibirsk

The aim of the study was to evaluate associations between content of surfactant proteins SP-A and SP-D and blood lipid parameters in men and women in Novosibirsk. Material and methods. In 2022, 174 people (87 men and 87 women), aged 45 to 69 years, randomly selected from the residents of Novosibirsk, were examined. Content of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG) in blood was determined by direct enzymatic method, concentration of surfactant proteins SP-A and SP-D – by enzyme immunoassay. Results. It was found that in the general sample of examined individuals, the content of SP-A in the blood is directly related to the level of HDL cholesterol and negative with the concentration of TG and hypertriglyceridemia; in men it was positively correlated with the level of HDL cholesterol, and in women it was positively correlated with low levels of HDL cholesterol (hypoHDL cholesterol). According to the results of ROC and multivariate analyze, it was found that blood SP-A level of at least 1642 pg/ml has a diagnostic value in the detection of hypo HDL-C in women (sensitivity is 56.3 %, specificity is 81.7 %,) and increases the risk of having hypo HDL-С in the total sample of the examined persons and in the women by 3.4 and 7.4 times, respectively. Using multivariate analysis, the reverse effect of blood SP-A content on hypertriglyceridemia was determined in the total sample of men and women in Novosibirsk. No associations were found between SP-D concentration and the studied lipid characteristics of the blood. One of the possible mechanisms of the SP-A influence on lipid metabolism (level of HDL-C, TG, hypoHDL-C, hypertriglyceridemia) in men and women in Novosibirsk is its effect on cell membranes, inducing the redistribution of the CD36 scavenger receptor, as well as changes in expression of this receptor.