Evaluation of the Mitochondria Respirometric Function in the Conditions of Pathologies of Various Geneses

Abstract

The aim of the paper is to assess the change in the mitochondrial respirometric function under conditions of various pathologies.Materials and methods. The study was performed on male Wistar rats. Experimental focal cerebral ischemia, traumatic brain injury, coronary occlusive myocardial infarction and muscle dysfunction were used as pathological models. Focal ischemia was reproduced by the method of irreversible thermocoagulation of the middle cerebral artery. Traumatic brain injury was modeled by the method of free fall of the load. Experimental myocardial infarction was reproduced by ligating the descending branch of the left coronary artery. Muscle dysfunction was modeled by the method of «forced swimming with a 20% burden». The respiratory function of mitochondria was assessed by the method of respirometry by the change in oxygen consumption when introducing mitochondrial respiration into the medium: Oligomycin, Rotenone and FCCP. Additionally, we evaluated the intensity of the glycolysis process and the activity of respiratory complexes I, II, IV and V. In order to comprehensively assess the respiratory function, an ELISA study was conducted to determine the concentration of ATP, mitochondrial ATP synthetase, cytochrome C oxidase and NADP-Oxidase 4.Results. In the course of the study it was established that under conditions of experimental cerebral ischemia, traumatic brain injury, myocardial infarction and muscle dysfunction, the ATP-generating ability of mitochondria the maximum breathing and respiratory capacity deteriorated, herby the decrease in overall respiratory function was accompanied by an increase in glycolysis, which was uncompensated, as well as dysfunction of mitochondrial complexes I, II, IV and V, confirmed by an increase in NADPH oxidase 4 activity and a decrease in cytochrome C oxidases and ATP synthetase. As a result, the observed changes in mitochondrial respiration function contributed to a decrease in ATP concentration under conditions of cerebral ischemia - by 3.2 times (p <0.05), traumatic brain injury – by 2.6 times (p <0.05), myocardial infarction – by 1.8 times (p <0.05) and muscle dysfunction – by 4 times (p <0.05).Conclusion. Basing on the data obtained, we can assume that in conditions of cerebral ischemia, traumatic brain injury, myocardial infarction and muscle dysfunction, there is deterioration of the mitochondrial respirometric function with inhibition of ATP synthesis and increased glycolysis.

Administration of 4-Hydroxy-3,5-Di-Tertbutyl Cinnamic Acid Restores Mitochondrial Function in Rabbits with Cerebral Ischemia

“…During the analysis, the biosample volume was 275 μl, and 25 μl of injected analyzers. Oxygen consumption was determined in ppm (17).…”

“…The optical density of the mixture was recorded at λ= 540nm, then the resulting solution was incubated for 25 min at room temperature with constant stirring. At the same time, the latent time of opening of the mitochondrial pore in seconds was evaluated (by changing the optical density of the incubation medium) (17).…”

“…The optical density of the mixture was recorded at λ=515 nm and λ=525 nm. The proton moving force (transmembrane electrochemical gradient, ∆Ψ) was determined by the difference in the optical density: ∆Ψ=A515-A525 (17).…”

Сerebroprotective effect of some phenolic acids under conditions of experimental brain ischemia

“…Все проводимые с животными манипуляции, а также их содержание соответствовали требованиям Европейской конвенции по защите позвоночных животных, используемых для экспериментальных и других научных целей (Страсбург, 1986 г. [20,21] (рис. 1).…”

Neuroprotective Effect of L-carnitine. Focus on Changing Mitochondrial Function

“…The resulting mixture was re-centrifuged, and the optical density of the chloroform extract of formazan was measured at 492 nm against pure chloroform. The calculation of the necrosis zone was expressed as a percentage of the total mass of the hemispheres by the formula (Voronkov et al 2019):…”