Academic literature on the topic 'Malonic dialdehyde (MDA)'

This paper discloses for the first time the effects of the gas phase (GP) and the tar of cigarette smoke on lipid peroxidation (LPO) and on the structure of different lipid regions in liposomes. The LPO development was analysed in terms of the total unsaturation of lipids (double-bond, DB, content) and the formation of dienic conjugates (DC), ketodienes (KD), and malonic dialdehyde (MDA). As expected, the exposure of liposomes to either the GP or the tar led to a significant decrease in the DB content. However, the formation of oxidation products revealed different dynamics: MDA generation was inhibited, while the formation of DC and KD increased during the first few hours of the LPO development followed by its inhibition. The smoke constituents exhibited opposite effects on the structure of the lipid bilayer of liposomes: the GP markedly enhanced the microviscosity of liposomal membranes, whereas the tar caused a drastic lowering of microviscosity.

Objective: To examine the parameters of lipid peroxidation (LPO) and antioxidant system (AOS) in children with hereditary hemolytic anemia (HHA). Methods: A study was conducted in the Pediatric Hematology Department of the National Medical Center "Shifobakhsh" in Dushanbe, Tajikistan, involving 60 patients diagnosed with HHA. Based on the severity of HHA, the patients were divided into three groups: 20 children (33%) with mild HHA, 23 children (39%) with moderate HHA, and 17 children (28%) with severe HHA. A control group was established, comprising 20 healthy children matched by gender and age to the study groups. For all participants, the study measured the parameters of LPO and AOS. Specific biomarkers evaluated included malonic dialdehyde (MDA), superoxide dismutase (SOD), and ascorbic acid (AA). Results: When comparing MDA levels in children from the control group (0.58 [0.48; 0.69] μmol/l) to those in study groups based on the severity of anemia, significant differences were observed. The MDA levels were as follows: mild anemia had levels of 1.62 [1.35; 1.78] μmol/l, moderate anemia had levels of 2.14 [2.10; 2.19] μmol/l, and severe anemia had levels of 3.10 [2.95; 3.12] μmol/l, with a statistically significant difference noted (p<0.001). Furthermore, significant differences were observed when evaluating the indicators of AOS, specifically SOD and AA levels. In patients with moderate anemia, the SOD was 9.6 [9.0; 9.8] U/ml, and AA levels were 45.1 [43.3; 47.2] mmol/l. In patients with severe anemia, SOD levels were lower at 7.4 [7.2; 7.7] U/ml, and AA levels were 39.5 [39.2; 39.8] mmol/l. In comparison, patients with mild anemia had SOD levels of 15.4 [15.1; 15.7] U/ ml and AA levels of 54.6 [52.3; 58.4] mmol/l. The control group had SOD levels of 14.4 [14.2; 14.9] U/ml and AA levels of 72.8 [70.0; 74.6] mmol/l. All comparisons showed statistically significant differences (p<0.001). Conclusion: The analysis of the study results revealed significant changes in LPO and AOS parameters, which were correlated with the severity of anemia, resulting in a worsening of the patients' condition. Keywords: Hereditary hemolytic anemia, lipid peroxidation, antioxidant system, oxidative stress, malonic dialdehyde, superoxide dismutase, ascorbic acid.

Введение. Состояние антиоксидантного статуса является неотъемлемым составляющим в регуляции обменных процессов в органах и тканях. При его низких емкостных резервах, обусловленных различными патологическими состояниями, наблюдается развитие окислительного стресса с последующим формированием синдрома полиорганной недостаточности, что является основанием для разработки мер по патогенетически оправданному лечению пациентов с циррозом печени и острой кровопотерей. Цель. Изучить некоторые показатели антиоксидантного статуса до лечения пациентов с циррозом печени и острой кровопотерей. Материалы и методы. В настоящее исследование было включено 267 пациентов с циррозом печени и острой кровопотерей различной степени тяжести, а также 20 практически здоровых добровольцев. У пациентов в день поступления в стационар до начала лечения производился забор крови для исследования ключевых показателей антиоксидантной системы: общей антиоксидантной емкости (АОЕ), общих SH-групп (T-SH), восстановленного глутатиона (GSH), продуктов окисления белков (AOPP) и малонового диальдегида (MDA). Результаты. В зависимости от степени тяжести цирроза печени и острой кровопотери у пациентов наблюдалось снижение показателей общей антиоксидантной емкости, восстановленного глутатиона, общих SH-групп, повышение показателей продуктов окисления белков и малонового диальдегида, что указывало на развитие окислительного стресса. Заключение. Исследование ключевых показателей антиоксидантного статуса – общей антиоксидантной емкости, общих SH-групп, восстановленного глутатиона, продуктов окисления белков и малонового диальдегида является ключевым индикатором в комплексной оценке глубины протеканий патофизиологических реакций формирования окислительного стресса у пациентов с циррозом печени и острой кровопотерей. Introduction. The state of antioxidant status is an integral component in the regulation of metabolic processes in organs and tissues. With its low capacity reserves caused by various pathological conditions, the development of oxidative stress with subsequent formation of multi-organ failure syndrome is observed, which is the basis for the development of measures for pathogenically justified treatment of patients with liver cirrhosis and acute blood loss. Purpose. To study some indices of antioxidant status before treatment of patients with liver cirrhosis and acute blood loss. Materials and methods. The present study included 267 patients with liver cirrhosis and acute blood loss of varying severity, as well as 20 practically healthy volunteers. Blood was collected from the patients on the day of admission to the hospital before treatment for the study of key indicators of the antioxidant system: total antioxidant capacity (АОЕ), total -SH groups (T-SH), reduced glutathione (GSH), protein oxidation products (AOPP) and malonic dialdehyde (MDA). Results. Depending on the severity of liver cirrhosis and acute blood loss, patients showed a decrease in total antioxidant capacity, reduced glutathione, total -SH groups, and an increase in protein oxidation products and malonic dialdehyde, indicating the development of oxidative stress. Conclusion. The study of key indicators of antioxidant status: total antioxidant capacity, total -SH group, reduced glutathione, protein oxidation products and malonic dialdehyde are the key indicators in the complex assessment of the depth of pathophysiological reactions of oxidative stress formation in patients with liver cirrhosis and acute blood loss.

The aim of our study was to analyze changes in the development of oxidative stress in the liver of rats with chronic alcohol intoxication against the background of systemic inflammatory response syndrome based on the study of catalase and superoxide dismutase activity, concentration of malonic dialdehyde, oxidatively modified proteins and sulfide anion and superoxide anion production. Methods. Experimental studies were performed on 12 male Wistar rats weighing 180‒220 g. Animals were divided into two groups: 1 ‒ control and 2 ‒ animals, on which we simulated alcoholic hepatitis and SIRS. The activity of catalase and superoxide dismutase (SOD), the concentration of malonic dialdehyde (MDA) , oxidatively modified proteins (OMP) sulfide anion and superoxide anion production were studied in the rat liver homogenate. The obtained results were subjected to statistical processing using the Mann-Whitney test. Results. Analyzing the development of oxidative stress in the liver of rats, on which we simulated the combined effects of SIRS and prolonged alcohol intoxication, we found that the activity of SOD increased by 1.72 times (P<0.05), and catalase decreased by 1.18 times (P<0.05) compared with the control group. The production of superoxide anion radical in the liver of rats increased 2.21 times (P<0.05) in the group of animals with combined exposure to bacterial LPS and alcohol intoxication compared to control. The concentration of MDA increased 2.25 times (P<0.05), and OMP by 9.5 times (P<0.05) compared with control group. The concentration of sulfide anion in the liver of rats under the conditions of modeling the combined effects of SIRS and alcohol intoxication decreased by 1.44 times (P <0.05) compared with the control. Conclusions. Modeling of alcohol intoxication against the background of systemic inflammatory response syndrome leads to oxidative damage to lipid and protein structures of the liver due to increased production of superoxide anion radical and imbalance of antiradical protection.