Antioxidant Roles of Heme Oxygenase, Carbon Monoxide, and Bilirubin in Cerebral Circulation during Seizures

Postictal cerebrovascular dysfunction is an adverse effect of seizures in newborn piglets. The brain heme oxygenase (HO) provides protection against cerebrovascular dysfunction. We investigated the contribution of reactive oxygen species (ROS) to seizure-induced vascular damage and the mechanism of HO vasoprotection. In a bicuculline model of seizures, we addressed the hypotheses: (1) seizures increase brain ROS; (2) ROS contribute to cerebral vascular dysfunction; (3) ROS initiate a vasoprotective mechanisms by activating endogenous HO; and (4) HO products have antioxidant properties. As assessed by dihydroethidium oxidation (ox-DHE), seizures increased ROS in cerebral vessels and cortical astrocytes; ox-DHE elevation was prevented by tiron and apocynin. An HO inhibitor, tin protoporphyrin, potentiated, whereas an HO-1 inducer, cobalt protoporphyrin, blocked seizure-induced increase in DHE oxidation. Heme oxygenase products carbon monoxide (CO) (CORM-A1) and bilirubin attenuated ox-DHE elevation during seizures. Antioxidants tiron and bilirubin prevented the loss of postictal cerebrovascular dilations to bradykinin, glutamate, and sodium nitroprusside. Tiron and apocynin abrogated activation of the brain HO during seizures. Overall, these data suggest that long-term adverse cerebrovascular effects of seizures are attributed to oxidative stress. On the other hand, seizure-induced ROS are required for activation of the endogenous antioxidant HO/CO/bilirubin system that alleviates oxidative stress-induced loss of postictal cerebrovascular function in piglets.

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Depletion of microglia mitigates cerebrovascular dysfunction in diet-induced obesity mice

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00086.2021 ◽

2021 ◽

Author(s):

Qing Shen ◽

Guo Zhang

Keyword(s):

Basilar Artery ◽

Vascular Dysfunction ◽

Underlying Mechanism ◽

Diet Induced Obesity ◽

Cerebrovascular Function ◽

Cerebrovascular Dysfunction ◽

Normal Body Weight ◽

Oxide Synthase ◽

Endothelial Nitric Oxide ◽

The Brain

Obesity is frequently associated with cerebrovascular dysfunction, however, the underlying mechanism remains less well understood. In this study, by using pharmacological approaches, we show that neuroinflammation involving microglia plays an important role in obesity-related cerebrovascular dysfunction. PLX3397 treatment, which leads to depletion of microglia, reduced the wall thickness and collagen deposition in the basilar artery of diet-induced obesity (DIO) mice. Besides, the phosphorylation of endothelial nitric oxide synthase (eNOS) at Ser1177 was enhanced, suggesting improved endothelial function of the basilar artery. The wire myography data show that acetylcholine-elicited relaxation of basilar artery isolated from DIO mice was improved after the treatment with PLX3397. Moreover, our data demonstrate that brain administration of IL-18 impaired cerebrovascular function in mice with normal body weight. Together, these data suggest that neuroinflammation involving microglia is important in obesity-related vascular dysfunction in the brain.

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The effect of carbon monoxide on meiotic maturation of porcine oocytes

PeerJ ◽

10.7717/peerj.10636 ◽

2021 ◽

Vol 9 ◽

pp. e10636

Author(s):

David Němeček ◽

Eva Chmelikova ◽

Jaroslav Petr ◽

Tomas Kott ◽

Markéta Sedmíková

Keyword(s):

Oxidative Stress ◽

Carbon Monoxide ◽

Heme Oxygenase ◽

Protein Localization ◽

Somatic Cells ◽

Antioxidant Properties ◽

Protoporphyrin Ix ◽

Antioxidant Effect ◽

Meiotic Maturation

Oxidative stress impairs the correct course of meiotic maturation, and it is known that the oocytes are exposed to increased oxidative stress during meiotic maturation in in vitro conditions. Thus, reduction of oxidative stress can lead to improved quality of cultured oocytes. The gasotransmitter carbon monoxide (CO) has a cytoprotective effect in somatic cells. The CO is produced in cells by the enzyme heme oxygenase (HO) and the heme oxygenase/carbon monoxide (HO/CO) pathway has been shown to have an antioxidant effect in somatic cells. It has not yet been investigated whether the CO has an antioxidant effect in oocytes as well. We assessed the level of expression of HO mRNA, using reverse transcription polymerase chain reaction. The HO protein localization was evaluated by the immunocytochemical method. The influence of CO or HO inhibition on meiotic maturation was evaluated in oocytes cultured in a culture medium containing CO donor (CORM-2 or CORM-A1) or HO inhibitor Zn-protoporphyrin IX (Zn-PP IX). Detection of reactive oxygen species (ROS) was performed using the oxidant-sensing probe 2′,7′-dichlorodihydrofluorescein diacetate. We demonstrated the expression of mRNA and proteins of both HO isoforms in porcine oocytes during meiotic maturation. The inhibition of HO enzymes by Zn-PP IX did not affect meiotic maturation. CO delivered by CORM-2 or CORM-A1 donors led to a reduction in the level of ROS in the oocytes during meiotic maturation. However, exogenously delivered CO also inhibited meiotic maturation, especially at higher concentrations. In summary, the CO signaling molecule has antioxidant properties in porcine oocytes and may also be involved in the regulation of meiotic maturation.

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Heme Oxygenase-1 Induction by Cobalt Protoporphyrin Ameliorates Cholestatic Liver Disease in a Xenobiotic-Induced Murine Model

International Journal of Molecular Sciences ◽

10.3390/ijms22158253 ◽

2021 ◽

Vol 22 (15) ◽

pp. 8253

Author(s):

Jung-Yeon Kim ◽

Yongmin Choi ◽

Jaechan Leem ◽

Jeong Eun Song

Keyword(s):

Oxidative Stress ◽

Liver Disease ◽

Heme Oxygenase ◽

Murine Model ◽

Liver Diseases ◽

Transforming Growth Factor ◽

Heme Oxygenase 1 ◽

Cholestatic Liver Disease ◽

Hepatocyte Apoptosis ◽

Cobalt Protoporphyrin

Cholestatic liver diseases can progress to end-stage liver disease and reduce patients’ quality of life. Although their underlying mechanisms are still incompletely elucidated, oxidative stress is considered to be a key contributor to these diseases. Heme oxygenase-1 (HO-1) is a cytoprotective enzyme that displays antioxidant action. It has been found that this enzyme plays a protective role against various inflammatory diseases. However, the role of HO-1 in cholestatic liver diseases has not yet been investigated. Here, we examined whether pharmacological induction of HO-1 by cobalt protoporphyrin (CoPP) ameliorates cholestatic liver injury. To this end, a murine model of 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet feeding was used. Administration of CoPP ameliorated liver damage and cholestasis with HO-1 upregulation in DDC diet-fed mice. Induction of HO-1 by CoPP suppressed the DDC diet-induced oxidative stress and hepatocyte apoptosis. In addition, CoPP attenuated cytokine production and inflammatory cell infiltration. Furthermore, deposition of the extracellular matrix and expression of fibrosis-related genes after DDC feeding were also decreased by CoPP. HO-1 induction decreased the number of myofibroblasts and inhibited the transforming growth factor-β pathway. Altogether, these data suggest that the pharmacological induction of HO-1 ameliorates cholestatic liver disease by suppressing oxidative stress, hepatocyte apoptosis, and inflammation.

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Abstract TP102: Modulation of Neuroinflammation by Haptoglobin Reduces Oxidative Stress and Improves ICH Outcomes

Stroke ◽

10.1161/str.47.suppl_1.tp102 ◽

2016 ◽

Vol 47 (suppl_1) ◽

Author(s):

Jenna Leclerc ◽

Alex Dang ◽

Juan Santiago-Moreno ◽

Sylvain Dore

Keyword(s):

Oxidative Stress ◽

Heme Oxygenase ◽

Functional Outcomes ◽

Ferric Iron ◽

Heme Oxygenase 1 ◽

High Morbidity ◽

Blood Components ◽

Autologous Whole Blood ◽

The Brain ◽

Histological Staining

Intracerebral hemorrhage (ICH) is a stroke subtype associated with high morbidity and mortality. With breakdown of the blood-brain barrier and entry of toxic blood components and metabolites within the brain, a highly oxidative environment ensues and leads to a toxic neuroinflammatory cascade. A major cause of the debilitation following brain hemorrhage is due to the direct toxicity of blood components, notably hemoglobin (Hb), the most upstream precipitating factor in the cascade. The acute phase plasma protein haptoglobin (Hp) binds Hb and inhibits its cytotoxic, pro-oxidative, and pro-inflammatory properties. In this study, we investigated whether the local and specific overexpression of Hp would aid in the safe detoxification and clearance of free Hb, thereby protecting the neuropil from Hb-mediated oxidative stress and improving ICH outcomes. Hp was overexpressed locally within the brain using uniquely designed adeno-associated viral vectors and ICH was induced using the intrastriatal autologous whole blood injection model. Functional outcomes were assessed by a 24-point neurological deficit score. At 72h post-hemorrhage, mice were sacrificed and brains collected for histological staining. Hp-overexpressing mice demonstrated smaller lesion volumes (p<0.05) with less blood accumulation (p<0.05) and improve neurologic status after ICH (p<0.05) when compared to an identically treated control group (n=11-13/group). Histological staining for Iba-1, GFAP, heme oxygenase-1, 4-hydroxynonenal, ferric iron, and myeloperoxidase was performed and revealed: 1) significantly less heme oxygenase-1 expression and lipid peroxidation, 2) a trend towards reduced peripheral neutrophil infiltration, 3) significantly increased cortical microgliosis and cortical and striatal astrogliosis, and 4) no changes in ferric iron content or striatal microgliosis. In conclusion, Hp overexpression in the brain reduces ICH-induced brain injury and improves functional outcomes. Locally modulating brain Hp levels could represent an important clinically relevant strategy for the treatment of ICH.

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Vascular function and arginine and dimethylarginines in gentamicin-induced renal failure: a possible effect of heme oxygenase 1 inducer hemin

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-2016-0578 ◽

2017 ◽

Vol 95 (12) ◽

pp. 1406-1413 ◽

Cited By ~ 2

Author(s):

Esra Aycan-Ustyol ◽

Merve Kabasakal ◽

Seldag Bekpinar ◽

F. Ilkay Alp-Yıldırım ◽

Ozge Tepe ◽

...

Keyword(s):

Oxidative Stress ◽

Heme Oxygenase ◽

Vascular Function ◽

Asymmetric Dimethylarginine ◽

Vascular Dysfunction ◽

Cardiovascular Complication ◽

Heme Oxygenase 1 ◽

Antioxidant Enzyme Activities ◽

Symmetric Dimethylarginine ◽

Inflammatory Changes

Increased oxidative stress and disturbance in nitric oxide bioavailability lead to endothelial dysfunction and cardiovascular complication in renal disease. Gentamicin (GM), a commonly used antibiotic, exhibits a toxic effect on renal proximal tubules. Prevention of its nephrotoxicity is important. Therefore, we investigated whether heme oxygenase 1 HO-1) induction influenced kidney and vascular function in GM-administered rats. GM (100 mg·kg–1·day–1; i.p.) was given to rats alone or together with hemin (20 mg·kg–1 on alternate days; i.p.) for 14 days. Plasma and kidney l-arginine, asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA) as well as kidney 4-hydroxynonenal (HNE) levels and myeloperoxidase (MPO) activity were measured. Histopathological examinations of kidney and relaxation and contraction responses of aorta were also examined. GM increased serum SDMA, urea nitrogen (BUN), and creatinine levels and caused histopathological alterations in the kidney. GM elevated HO-1 protein and mRNA expressions, 4-HNE level, and MPO activity and decreased antioxidant enzyme activities and l-arginine levels in the kidney. Decreased relaxation and contraction were detected in the aorta. Hemin restored renal oxidative stress and inflammatory changes together with vascular dysfunction, but did not affect SDMA, BUN, or creatinine levels. We conclude that HO-1 induction may be effective in improving renal oxidative stress, inflammation, and vascular dysfunction mediated by GM.

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Vascular Dysfunction Induced by Mercury Exposure

International Journal of Molecular Sciences ◽

10.3390/ijms20102435 ◽

2019 ◽

Vol 20 (10) ◽

pp. 2435 ◽

Cited By ~ 4

Author(s):

Tetsuya Takahashi ◽

Takayoshi Shimohata

Keyword(s):

Oxidative Stress ◽

Vascular Dysfunction ◽

Brain Parenchyma ◽

Transport Systems ◽

Mehg Exposure ◽

In Vivo Models ◽

The Central Nervous System ◽

The Brain

Methylmercury (MeHg) causes severe damage to the central nervous system, and there is increasing evidence of the association between MeHg exposure and vascular dysfunction, hemorrhage, and edema in the brain, but not in other organs of patients with acute MeHg intoxication. These observations suggest that MeHg possibly causes blood–brain barrier (BBB) damage. MeHg penetrates the BBB into the brain parenchyma via active transport systems, mainly the l-type amino acid transporter 1, on endothelial cell membranes. Recently, exposure to mercury has significantly increased. Numerous reports suggest that long-term low-level MeHg exposure can impair endothelial function and increase the risks of cardiovascular disease. The most widely reported mechanism of MeHg toxicity is oxidative stress and related pathways, such as neuroinflammation. BBB dysfunction has been suggested by both in vitro and in vivo models of MeHg intoxication. Therapy targeted at both maintaining the BBB and suppressing oxidative stress may represent a promising therapeutic strategy for MeHg intoxication. This paper reviews studies on the relationship between MeHg exposure and vascular dysfunction, with a special emphasis on the BBB.

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Protection of the vascular endothelium in experimental situations

Interdisciplinary Toxicology ◽

10.2478/v10102-011-0005-y ◽

2011 ◽

Vol 4 (1) ◽

pp. 20-26 ◽

Cited By ~ 16

Author(s):

Ružena Sotníková ◽

Jana Nedelčevová ◽

Jana Navarová ◽

Viera Nosáľová ◽

Katarína Drábiková ◽

...

Keyword(s):

Oxidative Stress ◽

Vascular Endothelium ◽

Vascular Dysfunction ◽

Antioxidant Properties ◽

Pharmacological Intervention ◽

Ros Production ◽

Nitric Oxide Radical ◽

Endothelium Dependent Relaxation

Protection of the vascular endothelium in experimental situationsOne of the factors proposed as mediators of vascular dysfunction observed in diabetes is the increased generation of reactive oxygen species (ROS). This provides support for the use of antioxidants as early and appropriate pharmacological intervention in the development of late diabetic complications. In streptozotocin (STZ)-induced diabetes in rats we observed endothelial dysfuction manifested by reduced endothelium-dependent response to acetylcholine of the superior mesenteric artery (SMA) and aorta, as well as by increased endothelaemia. Changes in endothelium-dependent relaxation of SMA were induced by injury of the nitric oxide radical (·NO)-signalling pathway since the endothelium-derived hyperpolarising factor (EDHF)-component of relaxation was not impaired by diabetes. The endothelial dysfunction was accompanied by decreased ·NO bioavailabity as a consequence of reduced activity of eNOS rather than its reduced expression. The results obtained using the chemiluminiscence method (CL) argue for increased oxidative stress and increased ROS production. The enzyme NAD(P)H-oxidase problably participates in ROS production in the later phases of diabetes. Oxidative stress was also connected with decreased levels of reduced glutathione (GSH) in the early phase of diabetes. After 10 weeks of diabetes, adaptational mechanisms probably took place because GSH levels were not changed compared to controls. Antioxidant properties of SMe1EC2 foundin vitrowere partly confirmedin vivo.Administration of SMe1EC2 protected endothelial function. It significantly decreased endothelaemia of diabetic rats and improved endothelium-dependent relaxation of arteries, slightly decreased ROS-production and increased bioavailability of ·NO in the aorta. Further studies with higher doses of SMe1EC2 may clarify the mechanism of its endothelium-protective effectin vivo.

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Medin aggregation causes cerebrovascular dysfunction in aging wild-type mice

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2011133117 ◽

2020 ◽

Vol 117 (38) ◽

pp. 23925-23931

Author(s):

Karoline Degenhardt ◽

Jessica Wagner ◽

Angelos Skodras ◽

Michael Candlish ◽

Anna Julia Koppelmann ◽

...

Keyword(s):

Healthy Aging ◽

Vascular Dysfunction ◽

Upper Body ◽

Dependent Manner ◽

Wild Type ◽

Brain Vasculature ◽

Cerebrovascular Function ◽

Age Related ◽

Novel Approach ◽

Cerebrovascular Dysfunction

Medin is the most common amyloid known in humans, as it can be found in blood vessels of the upper body in virtually everybody over 50 years of age. However, it remains unknown whether deposition of Medin plays a causal role in age-related vascular dysfunction. We now report that aggregates of Medin also develop in the aorta and brain vasculature of wild-type mice in an age-dependent manner. Strikingly, genetic deficiency of the Medin precursor protein, MFG-E8, eliminates not only vascular aggregates but also prevents age-associated decline of cerebrovascular function in mice. Given the prevalence of Medin aggregates in the general population and its role in vascular dysfunction with aging, targeting Medin may become a novel approach to sustain healthy aging.

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Reciprocal Effects of Oxidative Stress on Heme Oxygenase Expression and Activity Contributes to Reno-Vascular Abnormalities in EC-SOD Knockout Mice

International Journal of Hypertension ◽

10.1155/2012/740203 ◽

2012 ◽

Vol 2012 ◽

pp. 1-11 ◽

Cited By ~ 13

Author(s):

Tomoko Kawakami ◽

Nitin Puri ◽

Komal Sodhi ◽

Lars Bellner ◽

Toru Takahashi ◽

...

Keyword(s):

Oxidative Stress ◽

Heme Oxygenase ◽

Redox Homeostasis ◽

Inhibitory Effect ◽

Serum Adiponectin ◽

Causative Role ◽

Vascular Abnormalities ◽

Chronic Oxidative Stress ◽

Cobalt Protoporphyrin ◽

Physiological Abnormalities

Heme oxygenase (HO) system is one of the key regulators of cellular redox homeostasis which responds to oxidative stress (ROS) via HO-1 induction. However, recent reports have suggested an inhibitory effect of ROS on HO activity. In light of these conflicting reports, this study was designed to evaluate effects of chronic oxidative stress on HO system and its role in contributing towards patho-physiological abnormalities observed in extracellular superoxide dismutase (EC-SOD, SOD3) KO animals. Experiments were performed in WT and EC-SOD(−/−)mice treated with and without HO inducer, cobalt protoporphyrin (CoPP). EC-SOD(−/−)mice exhibited oxidative stress, renal histopathological abnormalities, elevated blood pressure, impaired endothelial function, reduced p-eNOS, p-AKT and increased HO-1 expression; although, HO activity was significantly (P<0.05) attenuated along with attenuation of serum adiponectin and vascular epoxide levels (P<0.05). CoPP, in EC-SOD(−/−)mice, enhanced HO activity (P<0.05) and reversed aforementioned pathophysiological abnormalities along with restoration of vascular EET, p-eNOS, p-AKT and serum adiponectin levels in these animals. Taken together our results implicate a causative role of insufficient activation of heme-HO-adiponectin system in pathophysiological abnormalities observed in animal models of chronic oxidative stress such as EC-SOD(−/−)mice.

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Sulforaphane Attenuates Isoproterenol-Induced Myocardial Injury in Mice

BioMed Research International ◽

10.1155/2020/3610285 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Lijuan Song ◽

Mudduluri Srilakshmi ◽

Yi Wu ◽

T. S. Mohamed Saleem

Keyword(s):

Oxidative Stress ◽

Myocardial Injury ◽

Antioxidant Properties ◽

Weight Ratio ◽

Heart Weight ◽

Thiobarbituric Acid Reactive Substance ◽

Mitochondrial Atpase ◽

Mitochondrial Enzymes ◽

Cardiac Markers ◽

Endogenous Antioxidant

The development of isoproterenol- (ISO-) induced oxidative stress in the myocardium results in myocardial necrosis. Sulforaphane (SFN-0.4% of sulforaphane from standardized broccoli sprout extract) possesses chemoprotective, antidiabetic, and antibacterial activities and is also active against cardiovascular-related problems due to its antioxidant properties. This study was designed to investigate the cardioprotective effect of SFN against isoproterenol-induced myocardial injury in mice. Healthy male Swiss albino mice weighing 20–30 g were used in this study. These mice were randomly divided into five groups ( n = 6 ). All the mice in the experimental groups received isoproterenol (5 mg/kg bw, via i.p.) consecutively for 2 days. The mice were treated with SFN (4 mg/kg bw) and α-tocopherol (TCF) (10 mg/kg bw) by oral gavage for 1-7 days as pre- and posttreatment for the prophylactic and treatment groups, respectively. On day 10, the following parameters were studied: heart weight to body weight ratio, antioxidant parameters, and cardiac markers; and mitochondrial enzymes were estimated for cardioprotection. Administration of isoproterenol in mice showed an increased level of serum cardiac markers and heart mitochondrial ATPase enzymes. An increased level of myocardial thiobarbituric acid-reactive substance and decreased levels of endogenous antioxidant enzymes indicated that oxidative stress is induced by isoproterenol in the myocardium. The administration of SFN in mice restored the levels of all biochemical parameters to near-normal levels. Histopathological studies further confirmed the protective effect of sulforaphane. This study concluded that treatment with SFN boosts the endogenous antioxidant activity and prevents isoproterenol-induced myocardial injury.

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