Markers Of Oxidative Injury Research Articles

Age-related Changes In Markers Of Oxidative Injury In Fast And Slow Muscles Of Male And Female Rats

Age-related Changes In Markers Of Oxidative Injury In Fast And Slow Muscles Of Male And Female Rats

Preliminary results of clinical, biochemical, and radiological investigation into the oxidative status in patients with rotator cuff tendinopathy.

We investigated oxidative status in patients with rotator cuff tendinopathy (RCT) and evaluated their relationship with radiological and clinical parameters. In this cross-section study, 88 patients with RCT (59 males and 29 females) and 86 healthy controls (66 males, 20 females) were enrolled. The sample consisted of nontraumatic patients who are suffering from shoulder pain because of rotator cuff disease, which was established by clinical tests and MRI scanning. Oxidative stress in patients with RCT was analyzed via the dynamic thiol/disulfide homeostasis (TDH). Thiol/disulfide homeostasis was measured by a new colorimetric method. Furthermore, oxidative stress was indirectly measured by serum total oxidant status (TOS), oxidative stress index (OSI), and total antioxidant capacity (TAC). Serum disulfide levels and the other oxidative stress parameters of the RCT group were significantly greater than those of the control group (P < .001 for all), whereas the anti-oxidative stress parameters remained unchanged (P > .05 for all). The lowest and highest serum disulfide levels were detected in patients with grades 1 and 3, respectively (P < .001). Furthermore, in a multiple regression analysis, the disulfide/natural thiol ratio (β=-4.886, P = .004) and the MRI grading (β=0.314, P=.001) were independently associated with the Western Ontario Rotator Cuff Index WORC score. We found an association between the levels of various serum markers of oxidative injury, especially serum disulfide levels, and the increasing severity of RCT. Thiol/disulfide homeostasis seems to play a critical role in RCT, both in the beginning and during the progression of disease.

Mitochondrial uncoupling proteins protect human airway epithelial ciliated cells from oxidative damage

Apical cilia on epithelial cells defend the lung by propelling pathogens and particulates out of the respiratory airways. Ciliated cells produce ATP that powers cilia beating by densely grouping mitochondria just beneath the apical membrane. However, this efficient localization comes at a cost because electrons leaked during oxidative phosphorylation react with molecular oxygen to form superoxide, and thus, the cluster of mitochondria creates a hotspot for oxidant production. The relatively high oxygen concentration overlying airway epithelia further intensifies the risk of generating superoxide. Thus, airway ciliated cells face a unique challenge of producing harmful levels of oxidants. However, surprisingly, highly ciliated epithelia produce less reactive oxygen species (ROS) than epithelia with few ciliated cells. Compared to other airway cell types, ciliated cells express high levels of mitochondrial uncoupling proteins, UCP2 and UCP5. These proteins decrease mitochondrial protonmotive force and thereby reduce production of ROS. As a result, lipid peroxidation, a marker of oxidant injury, decreases. However, mitochondrial uncoupling proteins exact a price for decreasing oxidant production; they decrease the fraction of mitochondrial respiration that generates ATP. These findings indicate that ciliated cells sacrifice mitochondrial efficiency in exchange for safety from damaging oxidation. Employing uncoupling proteins to prevent oxidant production, instead of relying solely on antioxidants to decrease postproduction oxidant levels, may offer an advantage for targeting a local area of intense ROS generation.

Ameliorative Potential of Ginger (Zingiber officinale) following Repeated Coexposure with Fluoride and Dimethoate in Blood and Brain of Wistar Rats

Coexposure to exogenous neurotoxins, such as fluoride (F−) and dimethoate (DM), is a serious public health concern. In the current study, Wistar rats were exposed to DM (1/10th LD50) and F− (4.5 ppm) in drinking water individually as well as in combination continuously for 28 days and the effectiveness of ginger and quercetin was assessed in combating the oxidative stress-mediated combined toxic effects on blood and brain. Significant (p&lt;0.05) reductions were observed in the levels of total antioxidant status (TAS), glutathione peroxidase (GPx), blood glutathione (GSH), activities of catalase (CAT), total thiols (TTH), superoxide dismutase (SOD), aryl esterase (AE), and acetylcholinesterase (AChE) whereas significant elevations (p&lt;0.05) in malondialdehyde (MDA) and advanced oxidation protein products (AOPP) were recorded in blood and brain of coexposed rats. Administration of ginger and quercetin significantly (p&lt;0.05) ameliorated the combined F- and DM-induced hematotoxicity as well as neurotoxicity as indicated by the levels of markers of oxidative injury in brain and blood in coexposed rats, which showed significant (p&lt;0.05) improvement. Moreover, pathological changes, such as neurodegeneration, perivascular edema, and gliosis, observed after combined F− and DM toxicity in the brain (cerebrum and cerebellum) were markedly reduced after ginger supplementation.

Galantamine mitigates neurotoxicity caused by doxorubicin via reduced neuroinflammation, oxidative stress, and apoptosis in rat model.

Doxorubicin (DXR) is commonly used as a drug for cancer treatment. However, there have been reports of neurotoxicity associated with chemotherapy. Galantamine (GLN) is a medication that inhibits cholinesterase activity, providing relief from the neurotoxic effects commonly seen in individuals with Alzheimer's disease. This study explored the potential ameliorative effect of GLN on brain neurotoxicity induced by DXR. Forty rats were allocated into four separate groups for a study that lasted for a period of fourteen days. The control group was given normal saline, DXR group was given 5 mg/kg DXR every three days (cumulative dose of 20 mg/kg) through intraperitoneal injection. The GLN group was given 5 mg/kg GLN through oral gavage daily, while the DXR+GLN group was given DXR+GLN simultaneously. An analysis of brain proteins using ELISA to assess apoptosis through the concentration of inflammation and oxidative injury markers. The DXR treatment led to increased neuroinflammation by elevation of nuclear factor kappa B (NF-κB), and cyclooxygenase-2 (COX-2), oxidative stress by rise of malondialdehyde (MDA), and decline of superoxide dismutase (SOD), and no changes in catalase and glutathione (GSH), cell death by elevation of Bax and caspase-3 and reduced Bcl-2, and increase lipid peroxidation, impaired mitochondrial function. When GLN is administered alongside DXR, it has been observed to positively impact various biological markers, including COX-2, NF-κB, MDA, SOD, Bax, Bcl-2, and caspase-3 levels. Additionally, GLN improves lipid peroxidation and mitochondrial activity. DXR therapy in rats results in the development of neurotoxicity, and a combination of GLN can recover these toxicities, suggesting GLN promising evidence for mitigating the neurotoxic effects induced by DXR.

Ameliorative Effect of Thymoquinone and Thymoquinone Nanoparticles against Diazinon-Induced Hepatic Injury in Rats: A Possible Protection Mechanism.

The health benefits of thymoquinone (TQ) have been a significant focus of numerous studies. However, more research is needed to ascertain whether its nano-form can effectively treat or prevent chronic diseases. In this study, we investigated how thymoquinone and its nanoparticles can mitigate liver damage induced by diazinon in male Wistar rats and explored the intracellular mechanisms involved. Forty-two Wistar male rats (n = 42) were randomly allotted into seven groups. Group 1 served as the control. Group 2 (vehicle) consisted of rats that received corn oil via a gastric tube daily. In Group 3 (TQ), rats were given a daily oral administration of TQ (40 mg/kg bw). Group 4 (thymoquinone nanoparticles, NTQ) included rats that received NTQ (0.5 mg/kg bw) orally for 21 days. Group 5 (DZN) involved rats that were administered diazinon (DZN, 15 mg/kg bw) orally. In Group 6 (TQ + DZN), rats first received TQ orally, followed by DZN. Group 7 (NTQ + DZN) consisted of rats receiving NTQ orally, then DZN. After 21 days of treatment, the rats were euthanized. After oral administration of DZN, liver enzymes were significantly elevated (p < 0.05). Additionally, there were noticeable increases in oxidative injury markers, such as nitric oxide, malondialdehyde, redox oxygen radicals, and overall increases in hydrogen peroxide and liver protein carbonyl concentrations. This was accompanied by the upregulation of apoptotic markers (Bax, caspase9, caspase 3, bax/Bcl2 ratio), inflammatory cytokines (TNF-α, IL-6), and DNA damage. There was also a noteworthy decrease (p < 0.05) in the activities of antioxidant enzymes and anti-apoptotic markers. However, the oral administration of thymoquinone or its nanoparticle form mitigated these diazinon complications; our histopathological findings corroborated our biochemical and molecular observations. In conclusion, the significant antioxidant properties of thymoquinone, or its nanoparticle form, in tandem with the downregulation of apoptotic markers and inflammatory cytokines, provided a protective effect against hepatic dysfunction caused by diazinon.

Moringa oleifera leaf extract ameliorates cisplatin evoked neurotoxicity in male wistar rats

The study was intended to explore the potential role of Moringa oleifera leaf extract (MOLE) on cisplatin (CIS) induced neuronal damage in experimental male rats. In the current work, animals were divided into four groups, six animals in each group. Group-1 (Normal) administered with Distilled water 1ml p.o. Group-2 (CIS) was received cisplatin 5mg/kg, ip. single dose. Group-3 (CIS + MOLE 200mg/kg) was orally administrated MOLE 200mg/kg, dissolved in water for 14 days with a cisplatin 5 mg/kg, ip. single dose on 10 day and Group-4 (CIS + MOLE 400mg/kg) was orally administrated MOLE 400mg/kg, dissolved in water for 14 days with a cisplatin 5mg/kg, ip. single dose on 10 day. After 14 days of MOLE dosing, the rats were sacrificed after anesthetizing with ketamine. Brain of individual rat was excised and processed for evaluation of oxidative injury markers like malonyl dialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), catalase and histopathological study. MOLE treated experimental groups explored a potential (P&amp;#60;0.001) protection against CIS induced neurotoxicity by elevating the GSH, SOD, catalase and suppressing MDA in the brain as well as amelioration of histopathological changes induced by CIS at different doses. Thus, investigational finding revealed that MOLE possess potential benefits against neurotoxicity induced by anti-cancer drug cisplatin by regulating oxidative stress markers and ameliorating neuronal death and alteration of microanatomy of rat brain.

Methanol Extract of Dryopteris dilatata Alleviates streptozotocin-induced Hyperglycaemia and Liver Injury in Male Wistar Rats in Type 2 Diabetes Mellitus

Dysfunctional pancreatic beta cell and impaired glucose metabolism in the liver has been implicated in streptozotocin (STZ)-type 2 diabetes mellitus and this has been linked with increased oxidative stress. Whether methanol extract of Dryopteris dilatata (MEDd), a flavonoid-rich plant can ameliorate STZ- type 2 diabetes liver damage remains an issue. Hence, this study investigated the effect of methanol extract of Dryopteris dilatata on STZ- type 2 diabetes mellitus in male Wistar rat. Animals were randomly selected into five groups (n=5) and were treated as follows; group 1 received distilled water (10ml/kg), Group 2 received only STZ (60mg/kg), Group 3 and 4 received STZ then 400 and 800mg/kg of MEDd respectively while Group 5 received STZ then pioglitazone (10mg/kg). Following 14 days of treatment, animals were euthanized and blood as well as spleen, liver, pancreas and kidney tissues were collected for further studies. Our results revealed that MEDd significantly reduced STZ-induced hyperglycaemia in Diabetic rats. Markers of oxidative injury (MDA, NO and GSH) were also significantly ameliorated in the pancreas and liver of the diabetic rats following treatment with MEDd. However, liver injury markers (ALT, AST and ALP) were significantly attenuated with marked decreased in organ weight in the diabetic rats after treatment with MEDd. We found that methanol extract of Dryopteris dilatata demonstrated anti-diabetogenic and hepato-protective potential by enhancing in vivo hepato-pancreatic antioxidant defence system.

Normothermic liver machine perfusion as a dynamic platform for regenerative purposes: What does the future have in store for us?

Liver transplantation has become an immense success; nevertheless, far more recipients are registered on waiting lists than there are available donor livers for transplantation. High-risk, extended criteria donor livers are increasingly used to reduce the discrepancy between organ demand and supply. Especially for high-risk livers, dynamic preservation using machine perfusion can decrease post-transplantation complications and may increase donor liver utilisation by improving graft quality and enabling viability testing before transplantation. To further increase the availability of donor livers suitable for transplantation, new strategies are required that make it possible to use organs that are initially too damaged to be transplanted. With the current progress in experimental liver transplantation research, (long-term) normothermic machine perfusion may be used in the future as a dynamic platform for regenerative medicine approaches, enabling repair and regeneration of injured donor livers. Currently explored therapeutics such as defatting cocktails, RNA interference, senolytics, and stem cell therapy may assist in the repair and/or regeneration of injured livers before transplantation. This review will provide a forecast of the future utility of normothermic machine perfusion in decreasing the imbalance between donor liver demand and supply by enabling the repair and regeneration of damaged donor livers.

Hesperidin Attenuates Oxidative Stress, Inflammation, Apoptosis, and Cardiac Dysfunction in Sodium Fluoride-Induced Cardiotoxicity in Rats.

Excessive fluoride intake has been reported to cause toxicities to brain, thyroid, kidney, liver and testis tissues. Hesperidin (HSP) is an antioxidant that possesses anti-allergenic, anti-carcinogenic, anti-oxidant and anti-inflammatory activities. Presently, the studies focusing on the toxic effects of sodium fluoride (NaF) on heart tissue at biochemical and molecular level are limited. This study was designed to evaluate the ameliorative effects of HSP on toxicity of NaF on the heart of rats in vivo by observing the alterations in oxidative injury markers (MDA, SOD, CAT, GPX and GSH), pro-inflammatory markers (NF-κB, IL-1β, TNF-α), expressions of apoptotic genes (caspase-3, -6, -9, Bax, Bcl-2, p53, cytochrome c), levels of autophagic markers (Beclin 1, LC3A, LC3B), expression levels of PI3K/Akt/mTOR and cardiac markers. HSP treatment attenuated the NaF-induced heart tissue injury by increasing activities of SOD, CAT and GPx and levels of GSH, and suppressing lipid peroxidation. In addition, HSP reversed the changes in expression of apoptotic (caspase-3, -6, -9, Bax, Bcl-2, p53, cytochrome c), levels of autophagic and inflammatory parameters (Beclin 1, LC3A, LC3B, NF-κB, IL-1β, TNF-α), in the NaF-induced cardiotoxicity. HSP also modulated the gene expression levels of PI3K/Akt/mTOR signaling pathway and levels of cardiac markers (LDH, CK-MB). Overall, these findings reveal that HSP treatment can be used for the treatment of NaF-induced cardiotoxicity.

Clinical and Biochemical Assessment of Lycopene Gel Combined With Nanohydroxyapatite Graft in Treatment of Grade II Furcation Defects: A Randomized Controlled Clinical Study

Background: This study aimed to evaluate the effects of lycopene gel, as a natural antioxidant, mixed with a nanohydroxyapatite graft (NHG) covered by an occlusive resorbable collagen membrane (CM) in the surgical treatment of grade II furcation defects and on the gingival crevicular fluid (GCF) levels of 8-hydroxydeoxyguanosine (8-OHdG), as a marker of oxidative injury. Methods: In this randomized controlled clinical study a total of 24 patients with grade II furcation defects were randomly assigned into three equal groups. Furcation defects in group I were managed with lycopene gel mixed with NHG and CM, group II with NHG and CM, and group III with open flap debridement only. Site-specific changes in clinical parameters including probing depth (PD), vertical clinical attachment level (VCAL), horizontal clinical attachment level (HCAL), radiographic maximum vertical depth (MAX V), and maximum horizontal depth (MAX H) were measured at baseline and six months postoperatively. Gingival crevicular fluid levels of 8-OHdG were analyzed using enzyme-linked immunosorbent assay (ELISA) at baseline, one week, and three months. Results: Surgical management of grade II furcation defects resulted in a significant reduction in PD and 8-OHdG levels and a gain in CAL, MAX V, and MAX H in all groups. The differences between lycopene treated sites compared to NHG and CM alone were not significant at six months but demonstrated significantly superior clinical parameters compared to open flap debridement alone. Conclusion: Lycopene does not confer a benefit when combined with NHG in the surgical treatment of grade II furcation defects.

Anti-diabetogenic and in vivo antioxidant activity of ethanol extract of Dryopteris dilatata in alloxan-induced male Wistar rats

Aims Oxido-inflammatory stress has been implicated as the main targets in alleviating diabetic complications induced by hyperglycaemia. Dryopteris dilatata: a bioactive plant serves great medicinal benefits in ethnopharmacology to ameliorate pathological conditions. This study investigated the protective effects of ethanol extract of Dryopteris dilatata (EEDD) in alloxan-induced diabetic rats through mechanism involving inhibition of oxidative stress and liver and kidney inflammatory markers. Methodology Male Wistar rats were made diabetic via alloxan monohydrate (100 mg/kg) administration intraperitoneally. Diabetic rats were post-treated with EEDD (800 mg/kg) and Metformin (50 mg/kg) orally for two weeks. Fasting blood sugar (FBS), body and organ weight change, markers of oxidative stress, liver and kidney inflammation were evaluated. Results Our results revealed that EEDD significantly reduced alloxan-induced hyperglycaemia in the diabetic rats after 5, 10 and 15 days of treatment. Markers of oxidative injury were also significantly ameliorated in the pancreas, liver and kidney of the diabetic rats following treatment with EEDD. However, liver and kidney injury markers were significantly attenuated with marked decreased organ weight in the diabetic rats after treatment with EEDD. Conclusion Here in, we found that Dryopteris dilatata could be used as nutraceuticals in the prevention and treatment of diabetes and its related complications through positively modulating oxidative stress and liver and kidney inflammatory markers

MiR-29a Alleviates High Glucose-induced Inflammation and Mitochondrial Dysfunction via Modulation of IL-6/STAT3 in Diabetic Cataracts

ABSTRACT Background: This in vitro study was designed to reveal the role of miR-29a in high glucose-induced cellular injury through the modulation of IL-6/STAT3 in diabetic cataracts. Methods: The expression of miR-29a and STAT3 in the lens capsules of patients with or without diabetes was determined by RT-PCR. The levels of the IL-6 proinflammatory cytokine in the aqueous humor were detected by ELISA. HLE B-3 cells were cultured in normal glucose (NG; 5 mM) or high glucose (HG; 40 mM). After transfection with miR-29a, si-STAT3, or a negative control vector, the levels of IL-6 and STAT3 were detected. A CCK-8 assay was used to determine cell viability. We used flow cytometry to assess changes in reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP), and apoptosis induced by oxidative stress. Western blotting was used to determine the expression of the oxidative injury markers superoxide dismutase (SOD) and malondialdehyde (MDA) and the apoptosis markers Bcl-2 and Bax. Results: Reduced miR-29a, increased STAT3 expression, and IL-6 release were demonstrated in the lens capsules and aqueous humor of patients with diabetes. The stimulation of apoptosis and the loss of MMP induced by HG were attenuated by transfection with a miR-29a mimic and si-STAT3. ROS production, increased MDA content, decreased SOD activity, and upregulation of the apoptotic proteins Bcl-2/Bax were also partially alleviated by miR-29a overexpression, which shows their roles in oxidative injury. Furthermore, transfection with a STAT3 overexpression vector reversed the effects of miR-29a. Conclusions: In conclusion, miR-29a mitigated HG-induced oxidative injury and exerted protective effects via IL-6/STAT3 signaling. Thus, miR-29a may be a potential therapeutic agent for diabetic cataracts.

Coenzyme Q10 improves the survival and reduces inflammatory markers in septic patients.

This study aimed to evaluate the effect of Coenzyme Q10 (CoQ10) administration to patients in the early phase of sepsis to determine its effect on the markers of inflammation and the clinical outcomes of septic patients. Previous studies showed that CoQ10 levels were decreased in septic patients and worsening of mitochondrial dysfunction was observed. In this randomized controlled trial septic patients (n=40) received 100 mg CoQ10 twice a day for seven days added to standard treatment of sepsis. As a primary endpoint levels of Interleukin 6 (IL-6), Tumor Necrosis Factor-α (TNF-α), Glutathione peroxidase and malondialdehyde (MDA) were assessed at baseline, third and 7th day after the intervention. Secondary endpoints included assessment of clinical scores and in-hospital mortality. There was no difference in baseline inflammatory and oxidative injury markers between the groups. TNF-α and MDA levels decreased significantly in the CoQ10 group on the 7th day of the study (P:0.003 for both). There was a significant difference in the in-hospital mortality in the CoQ10 group compared to the control group (P:0.01). These findings suggest that CoQ10 has a positive effect on clinical parameters as well as mitochondrial dysfunction when administered in the early phase of sepsis (Tab. 2, Fig. 1, Ref. 38).

Approaches for Reactive Oxygen Species and Oxidative Stress Quantification in Epilepsy.

Oxidative stress (OS) and excessive reactive oxygen species (ROS) production have been implicated in many neurological pathologies, including acute seizures and epilepsy. Seizure-induced damage has been demonstrated both in vitro and in several in vivo seizure and epilepsy models by direct determination of ROS, and by measuring indirect markers of OS. In this manuscript, we review the current reliable methods for quantifying ROS-related and OS-related markers in pre-clinical and clinical epilepsy studies. We first provide pieces of evidence for the involvement of different sources of ROS in epilepsy. We then discuss general methods and assays used for the ROS measurements, mainly superoxide anion, hydrogen peroxide, peroxynitrite, and hydroxyl radical in in vitro and in vivo studies. In addition, we discuss the role of these ROS and markers of oxidative injury in acute seizures and epilepsy pre-clinical studies. The indirect detection of secondary products of ROS such as measurements of DNA damage, lipid peroxidation, and protein oxidation will also be discussed. This review also discusses reliable methods for the assessment of ROS, OS markers, and their by-products in epilepsy clinical studies.

Feline urinary F2-isoprostanes measured by enzyme-linked immunoassay and gas chromatography-mass spectroscopy are poorly correlated.

15-F2T-isoprostanes are byproducts of lipid peroxidation and were determined to be the best marker of oxidative injury in a rodent model of oxidative stress. A previous study compared methods for measurement of urinary F2-isoprostanes (gas chromatography and negative ion chemical ionization-mass spectrometry, GC-NICI-MS; and ELISA) and found poor agreement in dogs, horses, and cows. Surprisingly, fair agreement between these methods was identified in a small population of cats. We evaluated the agreement between GC-NICI-MS and ELISA of urinary F2-isoprostanes in the urine of 50 mature cats ranging from healthy to systemically ill. All urine samples had detectable levels of F2-isoprostanes by both methods. Significant proportional bias and poor agreement were identified between the 2 methods (ρ = 0.364, p = 0.009) for all cats, and in subgroup analysis based on health status. The concentration of urinary F2-isoprostanes was significantly lower in systemically ill cats compared to healthy cats when measured by ELISA (p = 0.002) but not by GC-NICI-MS (p = 0.068). Our results indicate that GC-NICI-MS and ELISA have poor agreement when measuring urinary F2-isoprostanes in cats.

Ethanolic stem bark extract of Terminalia ivorensis A. Chev. protects against potassium dichromate–induced nephrotoxicity in rats

ObjectiveThe plant Terminalia ivorensis is used in traditional medicine as a diuretic and in the management of renal failure. We reported previously that the ethanol stem bark extract of the plant protects against gentamicin-induced renal and hepatic damage in rats. To further elucidate the mechanism of its renoprotective activity, we studied the effects of the extract on Potassium dichromate–induced nephrotoxicity in rats. The present study assessed the effectiveness of the ethanol stem bark extract of Terminalia ivorensis - against renal oxidative injury evoked by potassium dichromate. MethodsAdult Sprague Dawley rats pre-treated with (100–1000 mg/kg p.o. bwt) of Terminalia ivorensis extract for 5 days were challenged with a single dose of Potassium dichromate (20 mg/kg Sc) in the neck region on the 4th day. On the sixth day, renal function and markers of oxidative injury were assessed. ResultsTerminalia ivorensis (300–1000 mg/kg p.o) pre-treatment dose dependently prevented decreases in urine output in rats challenged with a nephrotoxic dose of Potassium Dichromate. The extract also protected the rats against Potassium dichromate-induced rise in serum electrolytes, urea and creatinine. Furthermore, it dose dependently prevented Potassium dichromate-induced decrease in renal glutathione (GSH) levels whereas tissue oxidative enzymes Superoxide dismutase (SOD) and catalase were protected from damage. Markers of lipid peroxidation such as level of renal Malondialdehyde (MDA) and myeloperoxidase (MPO) also decreased dose dependently when compare with Potassium dichromate treated groups. The extract also protected the histomorphology of the kidney against Potassium dichromate induced damage. ConclusionThe ethanol stem bark extract of Terminalia ivorensis protects kidney against Potassium dichromate-induced renal damage.

Prooxidant-antioxidant balance in the methylotrophic yeast Ogataea polymorpha exoposed to spermidine

Background. Many molecular compounds used by eukaryotic cells as antioxidant agents can directly interact with reactive oxygen/nitrogen species. Among them are polyamines – natural substances with pronounced antioxidant properties. The main polyamines are putrescine, spermidine, spermine. Spermidine is a positively charged polyamine that is synthesized from putrescine and serves a precursor of spermine. In particular, spermidine is distinguished by its anti-aging properties. When administered to several model organisms, it prolonged their lifespan and provided resistance to stress. Spermidine also limits overproduction of reactive oxigene species and reduces age-related oxidative protein damage, which accounts for its antioxidant activity. The aim of our study was to investigate the effects of exogenous spermidine in different concentrations on the prooxidant-antioxidant balance in the methylotrophic yeast Ogataea polymorpha naturally adapted to stressful conditions such as growth on toxic methanol-containing medium and cultivation at high temperatures (42–45 °C). Materials and Methods. In this work, O. polymorpha wild-type strain was used. Yeast cells were cultivated in the mineral medium with 0.1 % glucose for creating stressful conditions. Spermidine was added in 1 and 2 mM concentrations immediately before the start of yeast cultivation. Reactive oxygen species, the level of oxidative modifications of proteins and lipids, the concentration of reduced gluthatione, superoxide dismutase and catalase activities were assayed to examine the prooxidant-antioxidant state of the yeast cells. Results. In this study, we analyzed the effects of exogenous spermidine in different concentrations on the enzymatic (superoxide dismutase and catalase activity) and non-enzymatic (reduced glutathione) antioxidant defense systems and markers of oxidative injury (products of proteins and lipids oxidation) in the methylotrophic yeast O. polymorpha starved for glucose. It was revealed that 1 mM spermidine had a protective effect on O. polymorpha cells and decreased the content of products of the oxidative modification of proteins. At the same time, the superoxide dismutase and catalase activities and content of the reduced glutathione remained almost unchanged in the cells cultivated in the glucose-depleted medium with 1 mM spermidine compared to the medium without spermidine. Adverse effects of 2 mM spermidine (increased levels of carbonyl groups of proteins, lipid peroxidation products, disregulated superoxide dismutase and catalase activities, reduced glutathione levels, growth inhibition and cells vacuolization) were observed in the exponential growth phase of the yeast culture. During a long-term cultivation, these effects diminished, and the corresponding values approximated those of the cells grown in the control medium with the low concentration of glucose without spermidine. Conclusions. The data suggest a concentration-dependent effect of spermidine on the physiology of O. polymorpha that can be used in further studies on compounds able to mitigate negative effects of the oxidative stress in this yeast and other model organisms . At 1 mM concentration, spermidine had an apparent protective effect, whereas at the elevated 2 mM concentration this polyamine exacerbated stress load in this yeast. Keywords: methylotrophic yeast, Ogataea polymorpha , spermidine, oxidative stress

The effect of Roundup on the bivalve Unio tumidus mollusk utilizing ex vivo approach

Glyphosate is the worldwide used herbicide of the first priority. However, its biochemical effects in the aquatic animals are studied scantly. The ex vivo approach has been recently proposed to provide the express evaluation of the adverse impact without the treating of the organisms. The aim of this study was to verify this approach for the assessment of the toxicity of glyphosate to the bivalve mollusk. The samples of the gills and digestive gland tissues of freshwater bivalve Unio tumidus mollusk were exposed to a range of the concentrations of glyphosate (commercial formulation Roundup MAX) at the concentrations 13.3, 26.7, 66.8 and 133.6 µg×L -1 during 2 h at 20 °C followed by 15 h at ~ 2–4 o C. The markers of oxidative injury (total antioxidant activity, end-products of lipid peroxidation (TBARS) and protein carbonyls (PC)), cellular low weight thiols GSH/GSSG and metallothionein (MT), and cholinesterase activity as the index of neurotoxicity were analyzed. We also assayed the index of cell vitality as the lysosomal membrane stability from the Neutral Red Retention (NRR) test. The results have shown that the lowest concentrations of glyphosate caused the most prominent changes of the indices: the decrease of MT concentration (by ~ two times) and cholinesterase activity. The total antioxidant activity was decreased substantially in all exposures correspon­dingly to a decrease of the MT and/or GSH concentrations. However, the levels of TBARS and PC were not changed comparing to control detecting the early stage of the injury. Surprisingly, NRR increased in the exposures to higher concentrations of glyphosate, probably due to strong chelating ability of glyphosate or other compounds of formulation. This study allows us to detect the earlier biological effects of glyphosate in the low environmentally realistic concentrations. Further validation of this approach needs the comparison of the results in the ex vivo and in vivo experiments. Keywords: Roundup; bivalve mollusk; cytotoxicity; ex vivo

Extracellular vesicles from endothelial progenitor cells prevent steroid-induced osteoporosis by suppressing the ferroptotic pathway in mouse osteoblasts based on bioinformatics evidence

Abnormal antioxidative capabilities were observed in the pathogenesis of steroid-induced osteoporosis (SIOP). Ferroptosis is a recently discovered type of cell death that is characterized by the overproduction of ROS in response to GPX4 and system Xc− downregulation, which is mediated by an Fe2+ fenton reaction. However, investigations focusing on the relationship between ferroptosis and steroid-induced bone disease remain limited. In the present study, high-dose dexamethasone was used to establish a mouse SIOP model, and extracellular vesicles extracted from bone marrow-derived endothelial progenitor cells (EPC-EVs) alleviated the pathological changes in SIOP via microtomography (micro-CT), with elevations in bone volume (BV), bone surface (BS), trabecular thickness (Tb.Th), and trabecular connectivity density (Conn-D) and decreases in trabecular separation (Tb.sp) and the structure model index (SMI). Histopathological analysis, such as haematoxylin and eosin (HE) and Masson staining, showed that EPC-EVs treatment increased the volume and density of the trabecular bone and bone marrow. RNA sequencing (RNA-seq) and bioinformatics analysis revealed subcellular biological alterations upon steroid and EPC-EVs treatment. Compared with the control, high-dose dexamethasone downregulated GPX4 and system XC−, and the Kyoto Encyclopedia of Genes and Genomes (KEGG)-based gene set enrichment analysis suggested that the ferroptotic pathway was activated. In contrast, combination treatment with EPC-EVs partly reversed the KEGG-mapped changes in the ferroptotic pathway at both the gene and mRNA expression levels. In addition, alterations in ferroptotic marker expression, such as SLC3A2, SLC7A11, and GPX4, were further confirmed by RNA-seq. EPC-EVs were able to reverse dexamethasone treatment-induced alterations in cysteine and several oxidative injury markers, such as malondialdehyde (MDA), glutathione (GSH), and glutathione disulphide (GSSG) (as detected by ELISA). In conclusion, EPC-EVs prevented mouse glucocorticoid-induced osteoporosis by suppressing the ferroptotic pathway in osteoblasts, which may provide a basis for novel therapies for SIOP in humans.