Disturbances of citrulline homeostasis in patients with arterial hypertension

Abstract

BACKGROUND. Evaluation the level of citrulline (Cit) in the blood allows us to determine metabolic disorders in the proximal tubules of the kidneys. Previously, we showed that impaired metabolic function of the kidneys in hypertensive patients (AH) is expressed by an increase in the level of Cit. THE AIM was to determine diagnostically significant Cutoff value or exceeding Cit levels in the blood separately for men and women with hypertension. PATIENTS AND METHODS. We examined 115 hyperten sive patients with an estimated glomerular filtration rate ≥ 45 ml/min/1.73 m², included 44 men and 71 women aged 63 [56; 68] and 64 [53; 73] years, respectively. The comparison group included 30 older age group donors (11 men and 19 women). Determination of the levels of Cit, arginine (Arg) and others was carried out using high-performance liquid chromatography. RESULTS. Metabolic disorders: obesity – noted in 57 % of men and 50 % of women; and hypercholesterolemia in 30 and 33 % and hypertriglyceridemia in 37 and 29 % of patients, respectively. Metabolic dysfunction in the subgroups of men and women, according to Cit content, was expressed by an increase in its levels by an average of 32 and 29 %, respectively. ROC analysis determined the cutoff value for men > 49.1 μM Cit, p = 0.0023, which corresponds to 68 % sensitivity and 91 % specificity, and 46.3 μM (p = 0.0014) with 80 % sensitivity and specificity 63 % for women. CONCLUSION. A slight decrease in the metabolic functions of the kidneys affects Cit homeostasis, which has diagnostic value. According to the data obtained, renal metabolism ensures the content of Cit in the blood – not higher than 49.1 μM in men and women – 46.3 μM, before the onset of a violation of this metabolic function in patients with hypertension.