scholarly journals Featured Article: Accelerated decline of physical strength in peroxiredoxin-3 knockout mice

2016 ◽  
Vol 241 (13) ◽  
pp. 1395-1400 ◽  
Author(s):  
Yong-Gang Zhang ◽  
Li Wang ◽  
Tomonori Kaifu ◽  
Jingmin Li ◽  
Xiaoyan Li ◽  
...  
Keyword(s):  
Knockout Mice ◽  
Energy Supply ◽  
Skeletal Muscles ◽  
Oxidative Status ◽  
Oxygen Species ◽  
Wild Type ◽  
Physical Strength ◽  
Mitochondrial Dna Copy Number ◽  
In The Wild ◽  
Peroxiredoxin 3

As a member of peroxiredoxin family, peroxiredoxin-3 plays a major role in the control of mitochondrial level of reactive oxygen species. During the breeding of experimental mice, we noticed that the peroxiredoxin-3 knockout mice were listless with aging. In the present study, we compared the swimming exercise performance and oxidative status between peroxiredoxin-3 knockout mice ( n = 15) and wild-type littermates ( n = 15). At the age of 10 months, the physical strength of peroxiredoxin-3 knockout mice was much lower than the wild-type littermates. Increased oxidative damage and decreased mitochondrial DNA copy number of the animal skeletal muscles were observed in peroxiredoxin-3 knockout mice as compared to that in the wild-type littermates. In addition, we found increased apoptotic cells in the brains of peroxiredoxin-3 knockout mice. Our results suggest that the deficiency of peroxiredoxin-3 induces accelerated oxidative stress and mitochondrial impairment, resulting in the decrease of energy supply and cellular activities. Peroxiredoxin-3 might be involved in the inhibition of aging process.

scholarly journals Role of Peroxiredoxin III in the Pathogenesis of Pre-eclampsia as Evidenced in Mice

2010 ◽  
Vol 3 (1) ◽  
pp. 71-73 ◽  
Author(s):  
Lianqin Li ◽  
Masuo Obinata ◽  
Katsuyoshi Hori
Keyword(s):  
Oxidative Stress ◽  
Blood Pressure ◽  
Reactive Oxygen Species ◽  
Knockout Mice ◽  
Oxidative Status ◽  
Intracellular Reactive Oxygen Species ◽  
Oxygen Species ◽  
Wild Type ◽  
Pregnant Mice

As a member of peroxiredoxin (Prx) family, PrxIII has been demonstrated to play an important role in scavenging intracellular reactive oxygen species (ROS). Since PrxIII knockout mice exhibited oxidative stress in placentas resembling pathophysiologic changes in placentas of human pre-eclampsia, we measured blood pressure through the carotid artery and detected oxidative status by western blotting in pregnant mice. We did not notice hypertension in pregnant PrxIII knockout mice as compared with wild-type littermates, although endothelin-1 was overexpressed in PrxIII-deficient placentas. Our results indicate that PrxIII is not involved in pre-eclamptic development. Instead, PrxIII is an indispensable antioxidant in placentas where oxidative stress exists.

scholarly journals Unique Cellular and Biochemical Features of Human Mitochondrial Peroxiredoxin 3 Establish the Molecular Basis for Its Specific Reaction with Thiostrepton

Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 150
Author(s):  
Kimberly J. Nelson ◽  
Terri Messier ◽  
Stephanie Milczarek ◽  
Alexis Saaman ◽  
Stacie Beuschel ◽  
...  
Keyword(s):  
Oxygen Species ◽  
Mitochondrial Reactive Oxygen Species ◽  
Wild Type ◽  
Cellular Models ◽  
Chemotherapeutic Approach ◽  
Promising Target ◽  
Redox Responsive ◽  
Catalytic Cysteine ◽  
Increased Sensitivity ◽  
Peroxiredoxin 3

A central hallmark of tumorigenesis is metabolic alterations that increase mitochondrial reactive oxygen species (mROS). In response, cancer cells upregulate their antioxidant capacity and redox-responsive signaling pathways. A promising chemotherapeutic approach is to increase ROS to levels incompatible with tumor cell survival. Mitochondrial peroxiredoxin 3 (PRX3) plays a significant role in detoxifying hydrogen peroxide (H2O2). PRX3 is a molecular target of thiostrepton (TS), a natural product and FDA-approved antibiotic. TS inactivates PRX3 by covalently adducting its two catalytic cysteine residues and crosslinking the homodimer. Using cellular models of malignant mesothelioma, we show here that PRX3 expression and mROS levels in cells correlate with sensitivity to TS and that TS reacts selectively with PRX3 relative to other PRX isoforms. Using recombinant PRXs 1–5, we demonstrate that TS preferentially reacts with a reduced thiolate in the PRX3 dimer at mitochondrial pH. We also show that partially oxidized PRX3 fully dissociates to dimers, while partially oxidized PRX1 and PRX2 remain largely decameric. The ability of TS to react with engineered dimers of PRX1 and PRX2 at mitochondrial pH, but inefficiently with wild-type decameric protein at cytoplasmic pH, supports a novel mechanism of action and explains the specificity of TS for PRX3. Thus, the unique structure and propensity of PRX3 to form dimers contribute to its increased sensitivity to TS-mediated inactivation, making PRX3 a promising target for prooxidant cancer therapy.

scholarly journals Molecular and functional architecture of the mouse photoreceptor network

2020 ◽  
Vol 6 (28) ◽  
pp. eaba7232
Author(s):  
Nange Jin ◽  
Zhijing Zhang ◽  
Joyce Keung ◽  
Sean B. Youn ◽  
Munenori Ishibashi ◽  
...  
Keyword(s):  
Gap Junctions ◽  
Gap Junction ◽  
Knockout Mice ◽  
Conditional Knockout ◽  
Relative Importance ◽  
Wild Type ◽  
Functional Architecture ◽  
Rods And Cones ◽  
In The Wild

Mouse photoreceptors are electrically coupled via gap junctions, but the relative importance of rod/rod, cone/cone, or rod/cone coupling is unknown. Furthermore, while connexin36 (Cx36) is expressed by cones, the identity of the rod connexin has been controversial. We report that FACS-sorted rods and cones both express Cx36 but no other connexins. We created rod- and cone-specific Cx36 knockout mice to dissect the photoreceptor network. In the wild type, Cx36 plaques at rod/cone contacts accounted for more than 95% of photoreceptor labeling and paired recordings showed the transjunctional conductance between rods and cones was ~300 pS. When Cx36 was eliminated on one side of the gap junction, in either conditional knockout, Cx36 labeling and rod/cone coupling were almost abolished. We could not detect direct rod/rod coupling, and cone/cone coupling was minor. Rod/cone coupling is so prevalent that indirect rod/cone/rod coupling via the network may account for previous reports of rod coupling.

scholarly journals Angiotensin II stimulates superoxide production in the thick ascending limb by activating NOX4

2012 ◽  
Vol 303 (7) ◽  
pp. C781-C789 ◽  
Author(s):  
Katherine J. Massey ◽  
Nancy J. Hong ◽  
Jeffrey L. Garvin
Keyword(s):  
Angiotensin Ii ◽  
Nadph Oxidase ◽  
Knockout Mice ◽  
Thick Ascending Limb ◽  
Ang Ii ◽  
Wild Type ◽  
Outer Medulla ◽  
Catalytic Subunits ◽  
In The Wild

Angiotensin II (ANG II) stimulates production of superoxide (O2−) by NADPH oxidase (NOX) in medullary thick ascending limbs (TALs). There are three isoforms of the catalytic subunit (NOX1, 2, and 4) known to be expressed in the kidney. We hypothesized that NOX2 mediates ANG II-induced O2− production by TALs. To test this, we measured NOX1, 2, and 4 mRNA and protein by RT-PCR and Western blot in TAL suspensions from rats and found three catalytic subunits expressed in the TAL. We measured O2− production using a lucigenin-based assay. To assess the contribution of NOX2, we measured ANG II-induced O2− production in wild-type and NOX2 knockout mice (KO). ANG II increased O2− production by 346 relative light units (RLU)/mg protein in the wild-type mice ( n = 9; P < 0.0007 vs. control). In the knockout mice, ANG II increased O2− production by 290 RLU/mg protein ( n = 9; P < 0.007 vs. control). This suggests that NOX2 does not contribute to ANG II-induced O2− production ( P < 0.6 WT vs. KO). To test whether NOX4 mediates the effect of ANG II, we selectively decreased NOX4 expression in rats using an adenovirus that expresses NOX4 short hairpin (sh)RNA. Six to seven days after in vivo transduction of the kidney outer medulla, NOX4 mRNA was reduced by 77%, while NOX1 and NOX2 mRNA was unaffected. In control TALs, ANG II stimulated O2− production by 96%. In TALs transduced with NOX4 shRNA, ANG II-stimulated O2− production was not significantly different from the baseline. We concluded that NOX4 is the main catalytic isoform of NADPH oxidase that contributes to ANG II-stimulated O2− production by TALs.

Endothelial nitric oxide synthase-deficient mice exhibit increased susceptibility to endotoxin-induced acute renal failure

2004 ◽  
Vol 287 (5) ◽  
pp. F1044-F1048 ◽  
Author(s):  
Wei Wang ◽  
Amit Mitra ◽  
Brian Poole ◽  
Sandor Falk ◽  
M. Scott Lucia ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Renal Failure ◽  
Blood Flow ◽  
Acute Renal Failure ◽  
Knockout Mice ◽  
Endothelial Nitric Oxide Synthase ◽  
Wild Type ◽  
In The Wild ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Acute renal failure (ARF) in septic patients drastically increases the mortality to 50–80%. Nitric oxide (NO) has been shown to be increased in sepsis. Endothelial nitric oxide synthase (eNOS) is one of the major regulators of arterial blood pressure and regional blood flow; however, its in vivo role in septic ARF is still unclear. We hypothesized that eNOS affords a protective effect against the renal vasoconstriction during endotoxemia. Because there are no specific inhibitors for eNOS, the study was therefore undertaken in eNOS knockout mice. There was no significant difference in baseline glomerular filtration rate (GFR) between the wild-type mice and the eNOS knockout mice (140 ± 10 vs. 157 ± 18 μl/min, n = 9, P = not significant). However, renal blood flow (RBF) was significantly decreased in eNOS knockout mice compared with the wild-type controls (0.62 ± 0.05 ml/min, n = 6 vs. 0.98 ± 0.13 ml/min, n = 8, P < 0.05). Mean arterial pressure (MAP) was significantly higher in eNOS knockout mice than the wild-type controls (109 ± 5 vs. 80 ± 1 mmHg, n = 10, P < 0.01). Thus renal vascular resistance (RVR) was much higher in eNOS knockout mice than in the wild-type mice (176 ± 2, n = 6 vs. 82 ± 1 mmHg·ml−1·min−1, n = 8, P < 0.01). When 1.0 mg/kg LPS was injected, there was no change in MAP in either the wild-type (84 ± 3 mmHg, n = 10) or the eNOS knockout mice (105 ± 5 mmHg, n = 10). Although GFR (154 ± 22 μl/min, n = 8) and RBF (1.19 ± 0.05 ml/min, n = 9) remained unchanged with the 1.0-mg/kg dose of LPS in the wild-type mice, GFR (83 ± 18 vs. 140 ± 10 μl/min, n = 6, P < 0.01) and RBF (0.36 ± 0.04 vs. 0.62 ± 0.05 ml/min, n = 6, P < 0.01) decreased significantly in the eNOS knockout mice. Fractional excretion of sodium increased significantly in eNOS knockout mice during endotoxemia (3.61 ± 0.78, n = 7 vs. 0.95 ± 0.14, n = 6, P < 0.01), whereas it remained unchanged in the wild-type mice (0.59 ± 0.16, n = 9 vs. 0.42 ± 0.05, n = 6, P = not significant). In summary, eNOS knockout mice have increased RVR and are more susceptible to endotoxemic ARF than wild-type mice despite higher MAP.

scholarly journals Phagocyte-Derived Reactive Oxygen Species Do Not Influence the Progression of Murine Blood-Stage Malaria Infections

2005 ◽  
Vol 73 (8) ◽  
pp. 4941-4947 ◽  
Author(s):  
S. M. Potter ◽  
A. J. Mitchell ◽  
W. B. Cowden ◽  
L. A. Sanni ◽  
M. Dinauer ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Nadph Oxidase ◽  
Knockout Mice ◽  
Plasmodium Berghei ◽  
Gene Knockout ◽  
Reactive Oxygen ◽  
Plasmodium Yoelii ◽  
Oxygen Species ◽  
Wild Type ◽  
Gene Knockout Mice

ABSTRACT Phagocyte-derived reactive oxygen species have been implicated in the clearance of malaria infections. We investigated the progression of five different strains of murine malaria in gp91phox−/− mice, which lack a functional NADPH oxidase and thus the ability to produce phagocyte-derived reactive oxygen species. We found that the absence of functional NADPH oxidase in the gene knockout mice had no effect on the parasitemia or total parasite burden in mice infected with either resolving (Plasmodium yoelii and Plasmodium chabaudi K562) or fatal (Plasmodium berghei ANKA, Plasmodium berghei K173 and Plasmodium vinckei vinckei) strains of malaria. This lack of effect was apparent in both primary and secondary infections with P. yoelii and P. chabaudi. There was also no difference in the presentation of clinical or pathological signs between the gp91phox−/− or wild-type strains of mice infected with malaria. Progression of P. berghei ANKA and P. berghei K173 infections was unchanged in glutathione peroxidase-1 gene knockout mice compared to their wild-type counterparts. The rates of parasitemia progression in gp91phox−/− mice and wild-type mice were not significantly different when they were treated with l-N G -methylarginine, an inhibitor of nitric oxide synthase. These results suggest that phagocyte-derived reactive oxygen species are not crucial for the clearance of malaria parasites, at least in murine models.

Niacin stimulates adiponectin secretion through the GPR109A receptor

2009 ◽  
Vol 296 (3) ◽  
pp. E549-E558 ◽  
Author(s):  
Eric P. Plaisance ◽  
Martina Lukasova ◽  
Stefan Offermanns ◽  
Youyan Zhang ◽  
Guoqing Cao ◽  
...  
Keyword(s):  
Knockout Mice ◽  
Surface Expression ◽  
In Vivo Studies ◽  
Serum Adiponectin ◽  
Cell Surface Expression ◽  
Wild Type ◽  
The Metabolic Syndrome ◽  
In The Wild

Niacin (nicotinic acid) has recently been shown to increase serum adiponectin concentrations in men with the metabolic syndrome. However, little is known about the mechanism(s) by which niacin regulates the intracellular trafficking and secretion of adiponectin. Since niacin appears to exert its effects on lipolysis through receptor (GPR109A)-dependent and -independent pathways, the purpose of this investigation was to examine the role of the recently identified GPR109A receptor in adiponectin secretion. Initial in vivo studies in rats demonstrated that niacin (30 mg/kg po) acutely increases serum adiponectin concentrations, whereas it decreases NEFAs. Further in vitro studies demonstrated an increase in adiponectin secretion and a decrease in lipolysis in primary adipocytes following treatment with niacin or β-hydroxybutyrate (an endogenous ligand of the GPR109A receptor), but these effects were blocked when adipocytes were pretreated with pertussis toxin. Niacin had no effect on adiponectin secretion or lipolysis in 3T3-L1 adipocytes, which have limited cell surface expression of the GPR109A receptor. To further substantiate these in vitro findings, wild-type and GPR109A receptor knockout mice were administered a single dose of niacin or placebo, and serum was obtained for the determination of adiponectin and NEFA concentrations. Serum adiponectin concentrations increased and serum NEFAs decreased in the wild-type mice within 10 min following niacin administration. However, niacin administration had no effect on adiponectin and NEFA concentrations in the GPR109A receptor knockout mice. These results demonstrate that the GPR109A receptor plays an important role in the dual regulation of adiponectin secretion and lipolysis.

scholarly journals Serine hydroxymethyltransferase localised in the endoplasmic reticulum plays a role in scavenging H2O2 to enhance rice chilling tolerance

2020 ◽  
Author(s):  
Changxun Fang ◽  
Pengli Zhang ◽  
Lanlan Li ◽  
Luke Yang ◽  
Dan Mu ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Atp Synthase ◽  
Chilling Tolerance ◽  
Serine Hydroxymethyltransferase ◽  
Oxygen Species ◽  
Nucleic Acid Binding ◽  
Wild Type ◽  
Transcription Level ◽  
Family Protein ◽  
In The Wild

Abstract Background: Rice is a chilling-sensitive crop that would suffer serious damage from low temperatures. Overexpression of the Lsi1 gene (Lsi1-OX) in rice enhances its chilling tolerance. This study revealed that a serine hydroxymethyltransferase (OsSHMT) mainly localised in the endoplasmic reticulum (ER) is involved in increasing tolerance to chilling. Results: A higher transcription level of OsSHMT was detected in Lsi1-OX rice than in the wild type. Histone H1 and nucleic acid binding protein were found to bind to the promoter region of OsSHMT and regulate its expression, and the transcription levels of these proteins were also up-regulated in the Lsi1-OX rice. Moreover, OsSHMT interacts with ATP synthase subunit α, heat shock protein Hsp70, mitochondrial substrate carrier family protein, ascorbate peroxidase 1 and ATP synthase subunit β. Lsi1-encoded protein OsNIP2;1 also interacts with ATP synthase subunit β, and the coordination of these proteins appears to function in reducing reactive oxygen species, as the H2O2 content of transgenic OsSHMT Arabidopsis thaliana was lower than that of the non-transgenic line under chilling treatment. Conclusions: Our results indicate that ER-localised OsSHMT plays a role in scavenging H2O2 to enhance the chilling tolerance of Lsi1-OX rice and that ATP synthase subunit β is an intermediate junction between OsNIP2;1 and OsSHMT.

Isoflurane-induced Cerebral Hyperemia in Neuronal Nitric Oxide Synthase Gene Deficient Mice 

1997 ◽  
Vol 86 (4) ◽  
pp. 875-884 ◽  
Author(s):  
Hirotsugu Okamoto ◽  
Wei Meng ◽  
Jinya Ma ◽  
Cenk Ayata ◽  
Richard J. Roman ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Knockout Mice ◽  
Compensatory Mechanism ◽  
Wild Type ◽  
Doppler Flowmetry ◽  
Anesthetic Concentration ◽  
In The Wild ◽  
Oxide Synthase ◽  
Nos Isoforms

Background Nitric oxide (NO) has been reported to play an important role in isoflurane-induced cerebral hyperemia in vivo. In the brain, there are two constitutive isoforms of NO synthase (NOS), endothelial NOS (eNOS), and neuronal NOS (nNOS). Recently, the mutant mouse deficient in nNOS gene expression (nNOS knockout) has been developed. The present study was designed to examine the role of the two constitutive NOS isoforms in cerebral blood flow (CBF) response to isoflurane using this nNOS knockout mouse. Methods Regional CBF (rCBF) in the cerebral cortex was measured with laser-Doppler flowmetry in wild-type mice (129/SV or C57BL/6) and nNOS knockout mice during stepwise increases in the inspired concentration of isoflurane from 0.6 vol% to 1.2, 1.8, and 2.4 vol%. Subsequently, a NOS inhibitor, N omega-nitro-L-arginine (L-NNA), was administered intravenously (20 mg/kg), and 45 min later, the rCBF response to isoflurane was tested again. In separate groups of wild-type mice and the knockout mice, the inactive enantiomer, N omega-nitro-D-arginine (D-NNA) was administered intravenously in place of L-NNA. Brain NOS activity was measured with radio-labeled L-arginine to L-citrulline conversion after treatment with L-NNA and D-NNA. Results Isoflurane produced dose-dependent increases in rCBF by 25 +/- 3%, 74 +/- 10%, and 108 +/- 14% (SEM) in 129/SV mice and by 32 +/- 2%, 71 +/- 3%, and 96 +/- 7% in C57BL/6 mice at 1.2, 1.8, and 2.4 vol%, respectively. These increases were attenuated at every anesthetic concentration by L-NNA but not by D-NNA. Brain NOS activity was decreased by 92 +/- 2% with L-NNA compared with D-NNA. In nNOS knockout mice, isoflurane increased rCBF by 67 +/- 8%, 88 +/- 12%, and 112 +/- 18% at 1.2, 1.8, and 2.4 vol%, respectively. The increase in rCBF at 1.2 vol% was significantly greater in the nNOS knockout mice than that in the wild-type mice. Administration of L-NNA in the knockout mice attenuated the rCBF response to isoflurane at 1.2 and 1.8 vol% but had no effect on the response at 2.4 vol%. Conclusions In nNOS knockout mice, the cerebral hyperemic response to isoflurane is preserved by compensatory mechanism(s) that is NO-independent at 2.4 vol%, although it may involve eNOS at 1.2 and 1.8 vol%. It is suggested that in wild-type mice, eNOS and nNOS contribute to isoflurane-induced increase in rCBF. At lower concentrations (1.2 and 1.8 vol%), eNOS may be involved, whereas at 2.4 vol%, nNOS may be involved.

The role of adenosine in hypercarbic hyperemia: in vivo and in vitro studies in adenosine 2A receptor knockout and wild-type mice

2009 ◽  
Vol 110 (5) ◽  
pp. 981-988 ◽  
Author(s):  
Grzegorz Miekisiak ◽  
Kristen Yoo ◽  
Adam L. Sandler ◽  
Tobias B. Kulik ◽  
Jiang-Fan Chen ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Knockout Mice ◽  
Average Diameter ◽  
In Vitro Studies ◽  
Wild Type ◽  
Doppler Flowmetry ◽  
In The Wild

Object The authors tested the hypothesis that adenosine, acting through the A2A receptor, is not involved in hypercarbic hyperemia by assessing the effects of increased PaCO2 on cerebral blood flow (CBF) in vivo in wild-type and A2A receptor knockout mice. In addition, they evaluated the effect of abluminal pH changes in vitro on the diameter of isolated perfused penetrating arterioles harvested from wild-type and A2A receptor knockout mice. Methods The authors evaluated in a blinded fashion the CBF response during transient (60-second) hypercapnic (7% CO2) hypercarbia in anesthetized, ventilated C57Bl/6 wild-type and adenosine A2A receptor knockout mice. They also evaluated the hypercarbic response in the absence and presence of the nonselective and selective adenosine antagonists. Results Cerebral blood flow was measured using laser Doppler flowmetry. There were no differences between the CBF responses to hypercarbia in the wild-type and the knockout mice. Moreover, the hypercarbic hyperemia response was not affected by the adenosine receptor antagonists. The authors also tested the response to alteration in abluminal pH in isolated perfused, pressurized, penetrating arterioles (average diameter 63.3 ± 3.6 μm) harvested from wild-type (6 mice) and knockout (5 mice) animals. Arteriolar dilation in response to a decrease in abluminal pH, simulating the change in vivo during hypercarbia, was similar in wild-type (15.9 ± 2.6%) and A2A receptor knockout (17.7 ± 1.3%) mice. With abluminal application of CGS 21680 (10−6 M), an A2A receptor agonist, wild-type arterioles dilated in an expected manner (9.8 ± 0.7%), whereas A2A receptor knockout vessels had minimal response. Conclusions The results of the in vivo and in vitro studies in wild-type and A2A receptor knockout mice support the authors' hypothesis that hypercarbic vasodilation does not involve an adenosine A2A receptor–related mechanism.

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