The Proapoptotic Effect of Melatonin on the Functioning of the Nonspecific Mitochondrial Pore (mPTP) in Rat Mitochondria

2019 ◽  
Vol 13 (2) ◽  
pp. 156-163 ◽  
Author(s):  
Yu. L. Baburina ◽  
I. V. Odinokova ◽  
O. V. Krestinina
Keyword(s):  
2021 ◽  
pp. 130454
Author(s):  
John Oludele Olanlokun ◽  
Praise Oghenegare Okoro ◽  
Olatunde Segun Lawal ◽  
Olusola Bodede ◽  
Fisayo Olotu ◽  
...  

2010 ◽  
Vol 120 (10) ◽  
pp. 3680-3687 ◽  
Author(s):  
John W. Elrod ◽  
Renee Wong ◽  
Shikha Mishra ◽  
Ronald J. Vagnozzi ◽  
Bhuvana Sakthievel ◽  
...  

2014 ◽  
Vol 59 (6) ◽  
pp. 3-11 ◽  
Author(s):  
NA Strutyns'ka ◽  
◽  
RB Strutyns'kyĭ ◽  
SV Chorna ◽  
OM Semenykhina ◽  
...  

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3989-3989
Author(s):  
Claire Seedhouse ◽  
Abigail Whittall ◽  
Karuna Tandon ◽  
Nigel H. Russell ◽  
Monica Pallis

Abstract Abstract 3989 Objective: Approximately 50% of patients with acute myeloid leukaemia respond to remission-induction chemotherapy, but later relapse. Relapse is thought to be due to the continued presence of a quiescent, chemoresistant leukaemic cell subpopulation. Understanding the damage response in these cells might help to guide targeted therapies. We therefore developed an in vitro model of the quiescent subpopulation and used it to study drug-induced damage and repair in quiescent multidrug resistant cells. Methods: We cultured CD34+ CD38- multidrug resistant KG1a AML cells under several conditions reported to induce cell cycle arrest. We used Pyronin Y to measure RNA content and 7-aminoactinomycin D to measure cell viability. Chemosensitivity, reactive oxygen species (ROS), mitochondrial pore transition and oxidative damage were measured flow cytometrically. gammaH2A.X foci were quantified to measure the double strand break response and DNA damage response and repair gene expression was studied using PCR microarrays and confirmed by real time PCR. Results: mTOR inhibitors induced an increase in G0 without induction of apoptosis. 48 hours' exposure to rapamycin increased the proportion of G0 cells from 13.3% (SD 2.3%) to 46.1% (SD 6%) and decreased mean cell volume. Delayed re-entry into cell cycle following rapamycin withdrawal confirmed the G0 status of these cells. Differentiation markers remained negative. Although several of the other conditions studied resulted in reduced cell growth, they also induced apoptosis, as did combinations of rapamycin with other growth inhibitors. The toxicity of the chemotherapy drug daunorubicin, which acts in part by inducing ROS, was reduced in the quiescence-enriched cells. Sensitivity to mitochondrial pore transition was similar in proliferating and quiescence-enriched cells, indicating that apoptotic pathways are not impaired. However, both basal and drug-induced ROS were significantly lower in quiescence-enriched than in the proliferating cells (p=0.006 for basal ROS and 0.013 for daunorubicin-induced ROS). Furthermore, several DNA repair genes were differentially regulated following daunorubicin treatment of the quiescence-enriched compared to the proliferating cells – these included genes responsible for the repair of double strand breaks. On treatment with daunorubicin, double strand breaks, but not oxidative damage to DNA were observed in both cell populations. However, strikingly, although quiescence-enriched cells sustained fewer DNA damage foci than proliferating cells, they were unable to resolve the damage after daunorubicin was removed. Conclusion: By using rapamycin to enrich KG1a cells for quiescence, we have shown low basal and drug-induced ROS to be associated with chemoresistance in these cells. However, we also found that quiescence gave rise to an impaired double strand break response, which might force these cells to rely on alternative repair pathways and thus be sensitive to synthetic lethal targeting. Disclosures: No relevant conflicts of interest to declare.


Pathologia ◽  
2021 ◽  
Vol 18 (1) ◽  
pp. 26-32
Author(s):  
I. F. Bielenichev ◽  
A. A. Yehorov

Aim. To establish the effect of the glycine and thiotriazoline (4:1) combination on the parameters of the energy production of the mitochondria of the rat brain under the conditions of simulating an acute cerebrovascular accident. Materials and methods. The experimental part was performed on 90 male Wistar rats weighing 180–200 g. To model acute cerebrovascular accident (ACVA) by ischemic type, a classical model was used, where common carotid arteries had been ligated bilaterally. All animals were divided into 5 experimental groups: the first – intact (sham-operated rats, which during anesthesia had their common carotid arteries separated without ligation); the second – rats with ACVA (control); the third – rats with ACVA, which underwent intragastric administration of glycine at a dose of 200 mg/kg in the form of a tablet mass every day for 4 days; the fourth – rats with stroke, which every day for 4 days underwent intragastric administration of a combination of glycine and thiotriazoline (4:1) in the form of a tablet mass; the fifth – rats with ACVA, which underwent every day intragastric administration of piracetam in the form of a tablet mass at a dose of 500 mg/kg. The sampling of biological material (brain) for research was carried out on the fourth day of the experiment according to the standard method. The mitochondrial fraction was isolated by differential centrifugation in a refrigerated centrifuge. The manifestations of mitochondrial dysfunction, have been spectrophotometrically studied according to the degree of opening of the mitochondrial pore (MP) and mitochondrial transmembrane potential (Ψ). The assessment of the intensity of oxidative stress was determined by the markers of protein oxidative modification – aldehydephenylhydrazone (APH) and ketonedinitrophenylhydrazone (KPH) – spectrophotometrically. The state of energy metabolism was determined by the level of the most significant intermediates – ATP, lactate, succinate and malate. Results. In the group of animals with ACVA modeling, we noted a decrease in the level of ATP in mitochondria by 1.55 times, an increase in lactate content by 1.1 times, a decrease in SDH activity by 3.8 times and a decrease in succinate concentration by 1.1 times relative to the corresponding data of intact groups. Administration of a combination of glycine and thiotriazoline to experimental animals on the fourth day of ACVA modeling led to a 1.9-fold decrease in the opening of the mitochondrial pore and an increase in the charge of the inner mitochondrial membrane by 1.2 times, an increase in ATP in the mitochondrial fraction by 1.1 times, an increase in SDH activity by 3 times, and the activity of NAD-MDH – by 3.7 times, against the background of a decrease in the level of APH by 76.6 % and KPH by 80.7 %, relative to the group of animals with modeling of stroke by ischemic type. Conclusions. Modeling of ACVA leads to the initiation of oxidative stress and the development of an imbalance of energy metabolism intermediates in the brain mitochondria of experimental animals. Administration of a combination of glycine and thiotriazoline leads to a decrease in oxidative damage to mitochondria, increases the production of ATP due to the activation of compensatory mitochondrial-cytosolic shunts, mainly in malate-aspartate and succinate oxidase. In terms of the degree of influence on the indicators of energy metabolism, the combination of glycine and thiotriazoline reliably exceeds the similar actions of glycine and the reference drug - piracetam.


2005 ◽  
Vol 70 (7) ◽  
pp. 815-821 ◽  
Author(s):  
K. N. Belosludtsev ◽  
N. V. Belosludtseva ◽  
G. D. Mironova

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