Ferroptosis: regulated cell death Čepelak, Ivana; Dodig, Slavica; Dodig, Daniela Čepelak
Arhiv za higijenu rada i toksikologiju,
06/2020, Volume:
71, Issue:
2
Journal Article
Peer reviewed
Open access
Ferroptosis is a recently identified form of regulated cell death that differs from other known forms of cell death morphologically, biochemically, and genetically. The main properties of ferroptosis ...are free redox-active iron and consequent iron-dependent peroxidation of polyunsaturated fatty acids in cell membrane phospholipids, which results in the accumulation of lipid-based reactive oxygen species due to loss of glutathione peroxidase 4 activity. Ferroptosis has increasingly been associated with neurodegenerative diseases, carcinogenesis, stroke, intracerebral haemorrhage, traumatic brain injury, and ischemia-reperfusion injury. It has also shown a significant therapeutic potential in the treatment of cancer and other diseases. This review summarises current knowledge about and the mechanisms that regulate ferroptosis.
Earlier research has evidenced the oxidative and neurotoxic potential of imidacloprid, a neonicotinoid insecticide, in different animal species. The primary aim of this study was to determine how ...metabolic modulators piperonyl butoxide and menadione affect imidacloprid’s adverse action in the liver and kidney of Sprague-Dawley rats of both sexes. The animals were exposed to imidacloprid alone (170 mg kg-1) or in combination with piperonyl butoxide (100 mg kg-1) or menadione (25 mg kg-1) for 12 and 24 h. Their liver and kidney homogenates were analysed spectrophotometrically for glutathione peroxidase, glutathione S-transferase, catalase, total cholinesterase specific activities, total glutathione, total protein content, and lipid peroxidation levels. Imidacloprid displayed its prooxidative and neurotoxic effects predominantly in the kidney of male rats after 24 h of exposure. Our findings suggest that the observed differences in prooxidative and neurotoxic potential of imidacloprid could be related to differences in its metabolism between the sexes. Co-exposure (90-min pre-treatment) with piperonyl butoxide or menadione revealed tissue-specific effect of imidacloprid on total cholinesterase activity. Increased cholinesterase activity in the kidney could be an adaptive response to imidacloprid-induced oxidative stress. In the male rat liver, co-exposure with piperonyl butoxide or menadione exacerbated imidacloprid toxicity. In female rats, imidacloprid+menadione co-exposure caused prooxidative effects, while no such effects were observed with imidacloprid alone or menadione alone. In conclusion, sex-, tissue-, and duration-specific effects of imidacloprid are remarkable points in its toxicity
Rezultati ranijih istraživanja pokazali su oksidativni i neurotoksični potencijal imidakloprida, neonikotinoidnog insekticida, u različitih životinjskih vrsta. Primarni je cilj ovog istraživanja bio utvrditi kako modulatori metabolizma piperonil butoksid i menadion utječu na nepovoljne učinke imidakloprida na jetra i bubrege muških i ženskih štakora soja Sprague-Dawley. Životinje su 12 h odnosno 24 h bile izložene samo imidaklopridu (170 mg kg-1) ili njegovoj kombinaciji s piperonil butoksidom (100 mg kg-1) odnosno menadionom (25 mg kg-1). U homogenatima jetara i bubrega spektrofotometrijski su utvrđene razine glutation peroksidaze, glutation S-transferaze, katalaze, specifične aktivnosti ukupne kolinesteraze, ukupni glutation, ukupni proteini te razine lipidne peroksidacije. Imidakloprid se pokazao prooksidativnim i neurotoksičnim uglavnom u bubrezima muških štakora nakon 24-satne izloženosti. Naši rezultati upućuju na to da su razlike u prooksidativnom i neurotoksičnom djelovanju imidakloprida povezane sa spolnim razlikama. Predtretmanom piperonil butoksidom odnosno menadionom (90 min prije davanja imidakloprida) otkriveno je da imidakloprid djeluje na ukupnu aktivnost kolinesteraze specifično za pojedina tkiva. Povišena aktivnost kolinesteraza u bubrezima mogla bi odražavati prilagodbu na oksidativni stres uzrokovan imidaklopridom. Piperonil butoksid odnosno menadion u jetrima muških štakora samo su pogoršali toksičnost imidakloprida. U ženki je djelovanje imidakloprida s menadionom bilo prooksidativno; takvo se djelovanje nije vidjelo nakon primjene samo imidakloprida odnosno samo menadiona. Vjerujemo da je promjenjivo djelovanje imidakloprida s obzirom na spol, tkivo i trajanje izloženosti važno za daljnja istraživanja njegove toksičnosti
This paper reports the effects of selenium (Se) application on some physiological characteristics of barley (Hordeum vulgare L. cv. Rihane-03) exposed to drought stress. Foliar application to barley ...at 30 g selenium ha-1, as sodium selenate, increased significantly shoot dry weight and relative water content in well-watered plants. A remarkable reduction in dry weight of water-stressed plants was associated with significant decrease in maximal efficiency of PSII (Fv/Fm), stomatal conductance (gs) and net CO2 assimilation rate (A). Activity of antioxidant enzymes was increased by drought stress significantly. Amounts of malondialdehyde (MDA) and hydrogen peroxide (H2O2) remained unchanged in Sesupplemented water-deficit plants obviously because of an efficient scavenging following significant enhancement of catalase (CAT) and glutathione peroxidase (GSH-Px) activities. These results indicate that an application of selenium was favorable for biomass accumulation of barley plants under well-watered conditions. However, it did not significantly affect dry matter accumulation under drought stress, but Se-supplemented water-deficit plants exhibited better protection from oxidative damage because of higher CAT and GSH-Px activities and lower level of lipid peroxidation. These results suggest that selenium application can improve antioxidant defense system under drought stress conditions, and it may be recommended for arid and semiarid regions.
General anaesthetics are often used in patients who are under oxidative stress due to a critical illness or surgical trauma. Some anaesthetics may worsen oxidative stress and some may act as ...antioxidants. The aim of this study was to evaluate liver, brain, kidney, and lung tissue oxidative stress in rats exposed to desflurane and sevoflurane and in unexposed rats. The animals were divided in three groups: control (received only air); sevoflurane (8 %), and desflurane (4 %). After four hours of exposure, we evaluated the levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), Cu, and Zn. Exposure to either of the anaesthetics significantly increased lung MDA levels compared to control (Mann-Whitney U test; P<0.05), probably because it is the tissue directly exposed to anaesthetic gases. Oxidative stress and antioxidant activity in other tissues varied between the desflurane and sevoflurane groups. Our results suggest that anaesthesiologist should not only be aware of the oxidative or antioxidative potential of anaesthetics they use, but should also base their choices on organs which are the most affected by their oxidative action.
Poznato je da kirurške zahvate prati porast razine oksidativnog stresa, kako zbog stvaranja slobodnih kisikovih radikala tako i zbog smanjene aktivnosti obrambenih sustava koji se mogu oduprijeti njihovu djelovanju. Stoga su saznanja o antioksidativnom kapacitetu anestetika koji se primjenjuju prije nekoga kirurškog zahvata vrlo važna i od velikog su kliničkog značenja. Sevofluran i desfluran su inhalacijski anestetici koji se učestalo rabe u svrhu uvođenja bolesnika u anesteziju. Cilj ovog istraživanja bio je utvrditi razine oksidativnog stresa u različitim tkivima štakora i usporediti razlike u odgovoru tkiva na izlaganje navedenim anesteticima. U tu svrhu razine oksidativnog stresa izmjerili smo u jetri, mozgu, bubrezima i plućima štakora podijeljenih u tri eksperimentalne skupine. Kontrolna skupina udisala je samo zrak, dok su druge dvije skupine izložene 8 %-tnomu sevofluranu te 4 %-tnomu desfluranu tijekom 4 h. Nakon završetka obrade životinje su žrtvovane i uzimani su im uzorci tkiva za biokemijske analize. Mjerena je razina malondialdehida (MDA), aktivnost enzima superoksid dismutaze (SOD) i glutation peroksidaze (GSH-Px) te razine bakra i cinka. Izloženost anesteticima izazvala je oksidativni stres u plućima, na što upućuje značajno povišena razina MDA (Mann-Whitney U-test P<0.05) izmjerena u plućnom tkivu štakora obiju izloženih skupina u odnosu na kontrolu. Plućno je tkivo u odnosu na ostala tkiva podložnije štetnim utjecajima reaktivnih kisikovih radikala vjerojatno stoga što je ono prvo izloženo plinovitim anesteticima nakon njihova ulaska u organizam. Razine oksidativnog stresa i antioksidativne aktivnosti koje smo izmjerili u ostalim tkivima bile su različite te su ovisile o primijenjenom anestetiku. Na osnovi dobivenih rezultata možemo zaključiti da bi se zbog različitog odgovora tkiva izbor anestetika trebao provoditi na individualnoj osnovi.
Feroptoza: regulirana stanična smrt Čepelak, Ivana; Dodig, Slavica; Čepelak Dodig, Daniela
Arhiv za higijenu rada i toksikologiju,
06/2020, Volume:
71, Issue:
2
Journal Article
Peer reviewed
Open access
Feroptoza je nedavno identificirani oblik regulirane stanične smrti koji se od ostalih poznatih oblika stanične smrti razlikuje morfološki, biokemijski i genetski. Glavna svojstva feroptoze uključuju ...slobodno redoks aktivno željezo i posljedičnu, o željezu ovisnu, peroksidaciju polinezasićenih masnih kiselina u fosfolipidima staničnih membrana te gubitak aktivnosti glutation peroksidaze 4, što rezultira akumulacijom lipidnih, reaktivnih kisikovih spojeva. Feroptoza se sve više povezuje s raznim bolestima kao što su neurodegenerativne bolesti, karcinom, moždani udar, intracerebralna krvarenja, traumatične ozljede mozga i ishemijsko-reperfuzijska ozljeda. Također je pokazan značajan terapijski potencijal u liječenju raka i drugih bolesti. Ovaj pregled sažima trenutačne spoznaje i mehanizme koji reguliraju feroptozu.
The effects of the applied deiodinase blockers on the thyroid status of selenium adequate and selenium deficient juvenile rats were studied. The experiment was carried out on 128 male Wistar rats ...randomly allotted to 8 groups, 16 rats each. The following groups were formed: Se+PTU-IA- (control group), 2. Se+PTU+IA+, 3. Se+PTU+IA-, 4. Se+PTU-IA+, 5. Se-PTU-IA- , 6. Se-PTU+IA+, 7. Se-PTU+IA- i 8. Se-PTU-IA+. The first four groups were selenium adequate (Se+) and were fed a diet containing 0.334 mg/Se kg feed. Groups five, six, seven and eight were selenium deficient and fed 0.031 mgSe/ kg feed. As deiodinase blockers were used propylthiouracil (PTU+) in a dose of 150 mg/L potable water and iopanoic acid (IA+) in a dose of 6 mg/kg body mass applied intraperitoneally. After 3 and 7 weeks of treatment eight rats from each group were sacrificed and the following parameters were determined: thyroxine (T4), triiodothyronine (T3), Thyroid stimulating hormone (TSH), blood selenium concentration, erythrocyte cytosolic glutathione peroxidase activity (GPx1) and blood plasma glutathione peroxidase activity (GPx3). Selenium deficiency resulted in decreased body mass. Application of propylthiouracil resulted in decreased body mass by 19% in selenium adequate and by 59% in selenium deficient rats. A decrease in T4 and T3 concentration and increased TSH concentration in the blood plasma was recorded in both selenium adequate and selenium deficient groups treated with PTU after three weeks of treatment. After seven weeks T3 concentration in all selenium adequate rats was uniform, and selenium deficient PTU treated rats had decreased blood T3 concentrations. Concurrent use of IA and PTU in selenium deficient animals resulted in increased GPx1 activity after 3 weeks and GPx3 after 7 weeks of treatment. The use of PTU led to the loss of correlation between blood selenium and GPx1 treatment in both selenium adequate and deficient rats after three weeks of treatment. After seven weeks of treatment PTU (with or without the concurrent application of IA) resulted in the loss of correlation between blood selenium concentration and GPx3 activity. A negative correlation between T3 concentration and GPx1 activity in selenium deficient rats was recorded after three weeks of treatment, and between T3 concentration and GPx3 activity after seven weeks.
U okviru ove doktorske disertacije, ispitivan je uticaj primene blokatora dejodinaza na tireoidni status selenadekvatnih i selendeficitnih juvenilnih pacova. Ogled je izveden na ukupno 128 Wistar pacova muškog pola, podeljenih u osam grupa od po 16 jedinki. Formirane su sledeće grupe: 1. Se+PTU-IA- (kontrolna grupa), 2. Se+PTU+IA+, 3. Se+PTU+IA-, 4. Se+PTUIA+, 5. Se-PTU-IA-, 6. Se-PTU+IA+, 7. Se-PTU+IA- i 8. Se-PTU-IA+. Prve četiri grupe su bile selenadekvatne (Se+) i dobijale su hranu koja je sadržala 0.334 mg selena po kilogramu hrane. Grupe pet, šest, sedam i osam su bile selendeficitne (Se-) i dobijale su 0.031 mg selena po kilogramu hrane. Kao blokatori dejodinaza su korišćeni propiltiouracil (PTU+) u dozi od 150 mg/L vode za piće i jopanoična kiselina (IA+) u dozi od 6 mg/100g TM intraperitonealno. Nakon tri i sedam nedelja tretmana žrtvovano je po 8 jedinki iz svake grupe i određivani su sledeći parametri: tiroksin (T4), trijodtironin (T3), tireostimulirajući hormon (TSH), koncentracija selena u krvi, aktivnost citosolne glutation peroksidaze eritrocita (GPx1) i aktivnost glutation peroksidaze u krvnoj plazmi (GPx3). Deficit selena doveo je do blagog pada telesne mase jedinki. Primena propiltiouracila (PTU) dovela je do značajnog pada telesne mase od 19% kod selenadekvatnih jedinki i 59% kod selendeficitnih jedinki. Pad koncentracije T4 i T3 i porast koncentracije TSH u krvnoj plazmi zabeležen je kod selenadekvatnih i selendeficitnih jedinki tretiranih sa PTU, nakon tri nedelje tretmana. Nakon sedam nedelja, koncentracije T3 u krvi svih selenadekvatnih jedinki su bile ujednačene, a kod selendeficitnih jedinki je pri upotrebi PTU bila smanjena koncentracija T3 u krvi. Istovremena upotreba jopanoične kiseline i propiltiouracila kod selendeficitnih jedinki dovela je do rasta aktivnosti GPx1 nakon tri nedelje i GPx3 nakon sedam nedelja tretmana. Upotreba PTU je dovela do gubitka korelacione zavisnosti između koncentracije selena u krvi i aktivnosti GPx1 kod selenadekvatnih i selendeficitnih jedinki nakon tri nedelje tretmana, a nakon sedam nedelja tretmana, upotreba PTU sa ili bez jopanoične kiseline je dovela do gubitka korelacione zavisnosti između koncentracije selena u krvi i aktivnosti GPx3. Negativna korelaciona zavisnost između koncentracije T3 i aktivnosti GPx1 kod selendeficitnih jedinki uočena je nakon tri nedelje tretmana, a nakon sedam nedelja između koncentracije T3 i aktivnosti GPx3.
During the life cycle aerobic organisms are exposed to a number of endogenous
and exogenous sources of ROS. Present in low to moderate concentrations these
reactive molecules play an important role ...in many physiological processes
such as regulation of signaling cascades and gene expression. In high
concentrations, ROS can oxidize cellular proteins, lipids and DNA, causing
changes in structure and function, damage and even cell death. When the
concentration of free radicals exceeds the physiological level, a cell is
said to be in a state of oxidative stress. To prevent the onset and reduce
the consequences of oxidative stress, living organisms have developed
powerful antioxidant system (AOS). This system includes a set of mechanisms
to maintain the level of free radicals in the narrow range between
physiological and toxic concentrations. The most important enzyme components
in AOS are: superoxide dismutase (SOD), catalase (CAT), glutathione
peroxidase (GPx) and glutathione reductase (GR). These enzymes are involved
in the removal of ROS and participate in maintaining level of reduced
glutathione, thus ensuring the preservation of physiological functions and
inhibit the development of cell damage and disease. Because of such an
important role of AOS, the regulation of the functional expression of its
components is of particular importance for physiological and pathological
processes in aerobic organisms. One of the most important regulatory
molecules in this system is Nrf2 (NF-E2 related factor 2). Nrf2 is a
transcription factor that induces expression of many cytoprotective proteins
including antioxidant enzymes, and therefore play an important role in the
regulation of oxidative stress. Previous studies have clearly demonstrated a
link between oxidative stress and carcinogenesis. Cancer is a multistage
process that develops over three stages: initiation, promotion and
progression and oxidative stress is associated with each of them. Moreover,
antioxidant profile is altered in cancer cells compared with healthy, normal
tissue, so these molecules may be important biomarkers in the assessment of
risk and the degree of carcinogenesis. Endometrial cancer is one of the three
most common diseases of female reproductive organs. It has been shown that
benign and premalignant changes precede the malignant transformation of the
uterus, which is why these conditions may be considered as stages of
carcinogenesis. Despite numerous studies, the molecular processes involved in
multi-stage development of endometrial cancer are not yet fully known.
Therefore, the aim of this dissertation was to examine the changes in
expression of the four most important antioxidant enzymes in the blood and
tissues of patients with benign, premalignant and malignant endometrial
transformations, as well as the mechanism of their regulation by
transcription factor Nrf2. In this research we used endometrial tissue and
venous blood of patients diagnosed with: polypus endometrii, uterus
myomatosus, hyperplasia simplex endometrii, hyperplasia complex endometrii
and adenocarcinoma endometrii. Polypus endometrii and uterus myomatosus were
considered as benign, while hyperplasia simplex and hyperplasia complex
endometrii were considered as premalignant transformation of the uterus.
After adequate sample preparation, we initially determined the total protein
concentration in blood and endometrial tissue of all five groups of patients.
Then we performed SDS PAGE electrophoresis, transfer to nitrocellulose
membrane and chemiluminescent detection of CuZnSOD, CAT, GPx, GR and Nfr2
protein molecules. The protein levels were normalized with respect to
β-actin. Furthermore, in endometrial samples of all five groups of patients,
RNA was extracted and underwent reverse transcription into cDNA, followed by
the TaqMan Real-Time PCR method by which the amounts of CuZnSOD, CAT, GPx, GR
and Nfr2 mRNA were determined in respect to POLR2 as endogenous control. The
results of these experiments showed the following: 1. In comparison to
patients with polyps and myomas, in endometrium of women with hyperplasia
simplex and hyperplasia complex decreased levels of Nrf2 were recorded, while
in adenocarcinoma tissue Nrf2 protein level was increased. The observed
changes were regulated at the transcriptional level, except in adenocarcinoma
tissue in which increase in Nrf2 level was regulated by some
post-transcriptional mechanism. 2. CuZnSOD mRNA level and the amount of
CuZnSOD protein in the endometrium of patients with hyperplasia simplex and
hyperplasia complex were decreased compared to patients with polyps and
myomas. In adenocarcinoma tissue, however, the values of these parameters
were significantly increased compared to both benign and both premalignant
transformations. Observed transcriptional and translational CuZnSOD
variability in different stages of endometrial transformation were the
consequences of changes in the level of transcription factor Nrf2. 3.
Compared to the control groups with polyps and myomas, levels of CAT mRNA and
CAT protein were significantly decreased in the tissues of patients with
premalignant and malignant lesions of the uterus. It is also shown that Nrf2
had no direct effect on the CAT gene transcription, but acting on other
translational and posttranslational processes can probably influence the
level of this enzyme in the endometrium. 4. During carcinogenesis, increase
of GPx protein level was detected in premalignant endometrium, while decline
in the the amount of this enzyme was measured in adenocarcinoma tissue. GPx
level was positively correlated with the amount of transcription factor Nrf2,
but mechanism that regulates the expression of this enzyme varied with the
degree of tissue transformation. 5. In the course of malignant endometrial
transformation, increased expression of glutathione reductase was observed.
Consequent increased level of GR protein was the result not only of the
intensified transcription under the influence of Nrf2, but also of an
additional, posttranscriptional mechanism activated in transformed cells of
the uterus. 6. As regards AOE expression in the blood of examined patients,
it was observed that in comparison to the control group, in groups of women
with benign endometrial changes a decline in Nrf2 and GR levels were
measured, GPx level was increased, while the relative amounts of CuZnSOD and
CAT protein did not change significantly. Somewhat more pronounced changes
were observed in the blood of patients diagnosed with hyperplasia simplex,
hyperplasia complex and adenocarcinoma, characterized by declined protein
levels of Nrf2, CuZnSOD and GR, increased level of GPx and unaltered
expression of CAT. It was also shown that the blood expression levels of all
investigated AOE correlated positively with the amount of Nrf2. The results
of this dissertation indicate the existence and importance of the specific
expression pattern of antioxidant enzymes and transcription factor Nrf2 in
gynecological patients diagnosed with: polypus endometrii, uterus myomatosus,
hyperplasia simplex endometrii, hyperplasia complex endometrii and
adenocarcinoma endometrii. The observed changes confirm the important role of
the examined enzymes in complex molecular interactions that underlie the
transformation of endometrial cells. It is obvious that these AO molecules
not only influence the development of lesions in the uterine tissue, but they
are also an important factor for the progression of benign changes in
premalignant and malignant phenotype. It can be concluded that the results of
this dissertation contribute significantly to a better understanding of the
molecular processes involved in carcinogenesis. Implementation of this
knowledge in clinical practice could contribute to the quality of prevention,
diagnosis and treatment of gynecological patients, may lead to to improvement
in the disease course and prognosis and, consequently, may result in
increased survival rate of cancer patients.
Tokom čitavog životnog ciklusa aerobni organizmi su izloženi brojnim
endogenim i egzogenim faktorima koji indukuju povećanje produkcije ROS-a.
Prisutni u fiziološkim koncentracijama, reaktivni molekuli ROS-a imaju
značajnu ulogu u važnim ćelijskim procesima kao što su regulacija signalnih
kaskada i genske ekspresije. U visokim koncentracijama ROS mogu oksidovati
ćelijske proteine, lipide i DNK i time dovesti do promena strukture i
funkcije, oštećenja, pa i smrti ćelije. Kada koncentracija slobodnih radikala
premaši fiziološki nivo, smatra se da se ćelija nalazi u stanju oksidativnog
stresa. Kako bi sprečili nastanak i umanjili posledice ove vrste stresa, živi
organizmi su razvili moćan antioksidativni sistem zaštite (AOS). Ovaj sistem
uključuje seriju mehanizama kojima se nivo slobodnih radikala održava u uskom
opsegu između fiziološke i toksične koncentracije. Najvažnije enzimske
komponente AOS su: superoksid dismutaze (SOD), katalaza (CAT), glutation
peroksidaza (GPx) i glutation reduktaza (GR). Ovi enzimi uklanjaju višak
ROS-a i učestvuju u održavanju nivoa redukovanog glutationa, čime obezbeđuju
očuvanje osnovnih životnih funkcija i sprečavaju nastanak oštećenja i bolesti
ćelije. Zbog tako važne uloge AOS, regulacija funkcionalne ekspresije
njegovih komponenti je naročito značajna za fiziološke i patološke procese u
aerobnim organizmima. Jedan od najvažnijih regulatornih molekula u tom
sistemu je Nrf2 (NF-E2 related factor 2). Nrf2 je transkripcioni faktor koji
indukuje ekspresiju mnogih citoprotektivnih proteina uključujući i
antioksidativne enzime, zbog čega ima značajnu ulogu u regulaciji
oksidativnog stresa. Savremena istraživanja na različitim model-sistemima
ukazuju na povezanost oksidativnog stresa i kancerogeneze. Razvoj kancera je
višestepeni proces koji se razvija kroz tri faze: inicijaciju, promociju i
progresiju, a oksidativni stres je povezan sa svakim od ova tri stadijuma
transformacije ćelije. Osim toga i sam antioksidativni p
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