Introduction: High blood pressure is recognized to be a major problem in pediatrics, along with increasing obesity. The aggravated family history is one of the unchangeble risk factor, for the evolution of arterial hypertension (AH) in children. The last decade has been remarkable through multiple researches performed in order, to detect new markers in the early determination of AH, among which, it is worth mentioning the parameters of oxidative stress.

Objective: The aim of the study was to evaluate parameters of the enzyme antioxidant system in hypertensive children with overweight and family history aggravated by cardiovascular pathology.

Methods: The research included 75 children with an average age of 14.7 years divided into two research groups according to the presence of aggravated family history (FH) in the relatives of the first generation up to the age of 45 (group I- 35 hypertensive, overweight children, obese, FH- ; group II-40 of hypertensive, overweight and obese children with FH+). The excess weight was determined using BMI, and the diagnosis of hypertension was established according to the European Society of Cardiology Guide for hypertension in children and adolescents (2016). The parameters of the enzyme antioxidant system: Superoxide dismutase (SOD), Glutathione peroxidase (GPO), Glutathione reductase (GR) was determined by the enzyme immunoassay; Catalase (CAT) was assessed by spectropho-tometric method, and total antioxidant activity (TAA) was assessed by colorimetric method.

Results: We determined that AH grade I had 22 children (62.8%) from the group of AH, overweight, obese, FH-, and 25 children (62.5%) from the group of children AH, overweight, obese, FH+. Regarding grade II hypertension, it was established in 13 children (37.2%) from the group of AH, overweight, obese children, FH- and in 15 children (37.5%) from the group of AH, overweight, obese children, FH+. Children with hypertension, overweight, obese, FH+ or significantly highlighted compared with those, with FH- and the control group by decreased serum values of GPO- 6.77 nmol/s /L, GR-1.61 ng/ml and GST- 31.72 nmol/s/L (p< 0.001). The SOD activity in hypertensive, overweight, obese, FH+ children had the highest level (1296.68 u/g. Prot), compared to those of hypertension, overweight, obese, FH- (1281.76 u/g. Prot) and the control group (878.8 u/g. Prot) (p < 0.001). Regarding the serum level of CAT, we found that it was the most decreased in children with AH, overweight, obese, FH+ and was 15.69 mmol /s/l, compared to those with hypertension, overweight, obese, FH- (15,83 mmol/s/L) and the control groups (25.29 mmol/s/L) (p< 0.001). We found that TAA was the most decreased in the group of children with hypertension, overweight, obese, FH+ (0.43ABTS) compared to those in the group of hypertension, overweight, obese, FH- (0.44 ABTS) and the control group (0.58 ABTS) (p< 0.001).

Conclusions: The Serum levels of the GPO- 6.77 nmol/ s/L, GR- 1.61ng/ml and GST- 31.72 nmol/s/L as well as of the TAA- 0,43 ABTS were diminuated in children with AH, overweight, obese, FH+ versus the control group (GPO- 17.57 nmol/s/L; GR- 2.26 ng/ml; GST-37.41 nmol/s/L; TAA-0.58 ABTS), (p< 0.001), which indicates on the significant impairment of the antioxidant protection system. The highest values of SOD were determined in children with AH, overweight, obese, FH+ (1296.68 u/g. Prot) followed by the group of children with hypertension, overweight, obese, FH-(1281.76 u/g Prot) vs control group (878.8 u/g. Prot), as a compensatory mechanism for neutralizing the toxic effects of the superoxide anion (O2.-) (p< 0.001).