The lysyl oxidase inhibitor (β-aminopropionitrile) reduces leptin profibrotic effects and ameliorates cardiovascular remodeling in diet-induced obesity in rats

Abstract Background: Glaucoma is a neurodegenerative disease with the progressive loss of retinal ganglion cells and changes in the optic nerve head (ONH). These changes are exacerbated by an increase in intraocular pressure (IOP). Methods: The effect of scleral and optic nerve softening with beta aminopropionitrile a lysyl oxidase inhibitor (BAPN) and stiffening with genipin, in a model of chronic increase of IOP was evaluated. Changes in optic nerve and retina were evaluated. H&E, Bielschowsky's silver staining and glial fibrillary acid protein (GFAP) staining was performed on optic nerve, retina and scleral structures. Changes in the expression of the Ywhab, Yhwaz (prosurvival genes), C3 complement (complement C3 inflammatory marker), CPG15 (neurite growth and neural survival gene) GFAP (glial activator marker) genes was carried out in the different groups.Results: Protective effect of BAPN was evident by the preservation of the optic nerve structure, and with the conservation of the retinal structures, while deleterious changes were evident in the stiffening of ONH complex, characterized by the increase in the glia, changes in the optic nerve, and disorganization in the retina. BAPN induced a reduction in the expression of Ywhab, Yhwaz (prosurvival genes), C3 and GFAP (inflammatory and glial marker) and CPG15. Conclusions: These findings support the critical involvement of changes in the ONH stiffness in the progression of glaucoma. The control of this variable as a regulatory mechanism in the progression of neural glaucomatous damage must be considered and would be explored as a possible intervention in glaucoma management.

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Expression and properties of lysyl oxidase from archeal halophile Haloterrigena turkmenica

10.7287/peerj.preprints.2691v1 ◽

2017 ◽

Author(s):

Nikolay B Pestov ◽

Daniel V Kalinovsky ◽

Tatyana D Larionova ◽

Alia Z Zakirova ◽

Nikolai N Modyanov ◽

...

Keyword(s):

Catalytic Activity ◽

Amine Oxidase ◽

Lysyl Oxidase ◽

Polyclonal Antibodies ◽

Oxidase Inhibitor ◽

High Yield ◽

Transfer Event ◽

Oxidase Gene ◽

E Coli ◽

Haloterrigena Turkmenica

Background: Lysyl oxidases (LOX) were studied mostly in mammals, whereas properties of recently found homologs in prokaryotic genomes remain enigmatic. Methods: LOX gene from Haloterrigena turkmenica has been cloned by PCR in a E. coli expression vector. Protein purification has been done using metal affinity chromatography under denaturing conditions followed by refolding. Catalytic activity has been fluorometrically a release of hydrogen peroxide coupled with the oxidation of 10-acetyl-3,7-dihydroxyphenoxazine in the presence of horseradish peroxidase. Rabbit polyclonal antibodies were obtained and used in western blotting. Results: H. turkmenica LOX (HTU-LOX) may be successfully expressed in E. coli with a high yield. However, full-length protein gives no catalytic activity. On the other hand, a deletion of putative signal peptide allows the protein to be refolded into an active enzyme. Further deletion until the boundary of the catalytic C-terminal domain greatly increases the activity. Refolding is optimal at pH around 6.0, with addition of Cu2+, and surprisingly does not respond to changing concentration s of NaCl. The active HTU-LOX is sensitive to the lysyl oxidase inhibitor β-aminopropionitrile. HTU-LOX is active towards usual substrates of mammalian LOX such as lysine-containing basic peptides and polymers. The major difference between HTU-LOX and mammalian LOX is a relaxed specificity of the former. HTU-LOX readily oxidizes various amines including such compounds as taurine and glycine. Moreover, it is active also towards aminoglycoside antibiotics. Benzyl amine is a poor substrate for HTU-LOX. H. turkmenica cells or culture medium do not contain any detectable amine oxidase activity. Polyclonal antibodies against HTU-LOX detect a band among H. turkmenica proteins with the molecular weight corresponding to the unprocessed enzyme. Conclusion: H. turkmenica contains a lysyl oxidase gene that may give active recombinant enzyme with important biochemical features conserved, for example, sensitivity to β-aminopropionitrile. However, its function in the host may be cryptic. Significance: This is the first report on some properties of lysyl oxidase that originated from a horizontal transfer event into Archea.

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Pan-lysyl oxidase inhibitor PXS-5505 ameliorates multiple-organ fibrosis by inhibiting collagen crosslinks in rodent models of systemic sclerosis

10.22541/au.163847931.19877269/v1 ◽

2021 ◽

Author(s):

Yimin Yao ◽

Alison Findlay ◽

Jessica Stolp ◽

Benjamin Rayner ◽

Kjetil Ask ◽

...

Keyword(s):

Systemic Sclerosis ◽

Lysyl Oxidase ◽

Multiple Organ ◽

Oxidase Inhibitor ◽

Lung Model ◽

Rodent Models ◽

Collagen Crosslinks ◽

Fibrotic Liver ◽

Lysyl Oxidases ◽

Organ Fibrosis

Background/Purpose: Systemic sclerosis (SSc) is characterised by progressive multiple-organ fibrosis leading to morbidity and mortality. Lysyl oxidases play a vital role in the cross-linking of collagens and subsequent build-up of fibrosis in the extracellular matrix. As such, their inhibition provides a novel treatment paradigm for SSc. Experimental Approach: Lysyl oxidases are upregulated in preclinical models of fibrosis in skin, lung, heart, kidney and liver. A novel small molecule pan-lysyl oxidase inhibitor, PXS-5505, currently in clinical development for bone fibrosis treatment was evaluated in in vivo rodent models resembling the fibrotic conditions in SSc. Key Results: Both lysyl oxidase and lysyl oxidase-like 2 (LOXL2) expression was elevated in the skin and lung of SSc patients. Once-a-day oral application of PXS-5505 inhibited lysyl oxidase activity in the skin and LOXL2 activity in the lung. PXS-5505 exhibited anti-fibrotic effects in the SSc skin mouse model, reducing dermal thickness and α-smooth muscle actin compared to the disease controls. Similarly, in the bleomycin-induced mouse lung model, PXS-5505 reduced tissue fibrosis toward normal levels. The anti-fibrotic efficacy of PXS-5505 in the bleomycin exposed lungs was mediated by its ability to normalise collagen/elastin crosslink formation, a direct consequence of lysyl oxidase inhibition. PXS-5505 also reduced area of fibrosis in rodent models of the ischaemia-reperfusion heart, the unilateral ureteral obstruction kidney and the CCl4-induced fibrotic liver. Conclusion/Implication: PXS-5505 consistently demonstrates potent anti-fibrotic efficacy in multiple models of organ fibrosis relevant to the pathogenesis of SSc, suggesting that it may be efficacious as a novel approach for treating SSc.

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Increased stiffness of the rat liver precedes matrix deposition: implications for fibrosis

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00032.2007 ◽

2007 ◽

Vol 293 (6) ◽

pp. G1147-G1154 ◽

Cited By ~ 334

Author(s):

Penelope C. Georges ◽

Jia-Ji Hui ◽

Zoltan Gombos ◽

Margaret E. McCormick ◽

Andrew Y. Wang ◽

...

Keyword(s):

Lysyl Oxidase ◽

Liver Stiffness ◽

Oxidase Inhibitor ◽

Late Time ◽

Fresh Tissue ◽

Time Points ◽

Matrix Deposition ◽

Portal Fibroblasts ◽

Sirius Red

Liver fibrosis, the response to chronic liver injury, results from the activation of mesenchymal cells to fibrogenic myofibroblasts. We have recently shown that two key myofibroblast precursor populations, hepatic stellate cells and portal fibroblasts, undergo activation in culture in response to increasing substrate stiffness. We therefore hypothesized that alterations in liver stiffness precede myofibroblast activation and fibrosis in vivo as well. To test this hypothesis, we induced fibrosis in rats by twice weekly injections of carbon tetrachloride (CCl4) and then killed the animals at various time points ranging from 3 to 70 days after the initiation of injury. The shear storage modulus of the whole liver was measured on fresh tissue; fixed and frozen tissue from the same livers was used to quantify fibrosis. We observed that liver stiffness increased immediately and continued to increase, leveling out by day 28. Fibrosis, measured histologically by trichrome staining as well as by quantitative sirius red staining, increased with time, although these increases were delayed relative to changes in stiffness. There was no direct correlation between stiffness and fibrosis at early or late time points. Treatment of a second cohort of rats with the lysyl oxidase inhibitor, β-aminopropionitrile (BAPN), partially prevented early increases in liver stiffness. We concluded that increases in liver stiffness precede fibrosis and potentially myofibroblast activation. Liver stiffness appears to result from matrix cross-linking and possibly other unknown variables in addition to matrix quantity. We suggest that increased liver stiffness may play an important role in initiating the early stages of fibrosis.

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Collagen and elastin cross-linking is altered during aberrant late lung development associated with hyperoxia

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00039.2015 ◽

2015 ◽

Vol 308 (11) ◽

pp. L1145-L1158 ◽

Cited By ~ 39

Author(s):

Ivana Mižíková ◽

Jordi Ruiz-Camp ◽

Heiko Steenbock ◽

Alicia Madurga ◽

István Vadász ◽

...

Keyword(s):

Lung Development ◽

Lysyl Oxidase ◽

Oxidase Inhibitor ◽

Cross Linking ◽

Newborn Mice ◽

Hyperoxia Exposure ◽

Cross Links ◽

Mouse Lungs ◽

Alveolar Surface ◽

Alveolar Gas Exchange

Maturation of the lung extracellular matrix (ECM) plays an important role in the formation of alveolar gas exchange units. A key step in ECM maturation is cross-linking of collagen and elastin, which imparts stability and functionality to the ECM. During aberrant late lung development in bronchopulmonary dysplasia (BPD) patients and animal models of BPD, alveolarization is blocked, and the function of ECM cross-linking enzymes is deregulated, suggesting that perturbed ECM cross-linking may impact alveolarization. In a hyperoxia (85% O2)-based mouse model of BPD, blunted alveolarization was accompanied by alterations to lung collagen and elastin levels and cross-linking. Total collagen levels were increased (by 63%). The abundance of dihydroxylysinonorleucine collagen cross-links and the dihydroxylysinonorleucine-to-hydroxylysinonorleucine ratio were increased by 11 and 18%, respectively, suggestive of a profibrotic state. In contrast, insoluble elastin levels and the abundance of the elastin cross-links desmosine and isodesmosine in insoluble elastin were decreased by 35, 30, and 21%, respectively. The lung collagen-to-elastin ratio was threefold increased. Treatment of hyperoxia-exposed newborn mice with the lysyl oxidase inhibitor β-aminopropionitrile partially restored normal collagen levels, normalized the dihydroxylysinonorleucine-to-hydroxylysinonorleucine ratio, partially normalized desmosine and isodesmosine cross-links in insoluble elastin, and partially restored elastin foci structure in the developing septa. However, β-aminopropionitrile administration concomitant with hyperoxia exposure did not improve alveolarization, evident from unchanged alveolar surface area and alveoli number, and worsened septal thickening (increased by 12%). These data demonstrate that collagen and elastin cross-linking are perturbed during the arrested alveolarization of developing mouse lungs exposed to hyperoxia.

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Reversal of Fibrosis in Chronic Rejection in Mouse Airways through Combined Relaxin and Lysyl Oxidase Inhibitor Therapy

Annals of the American Thoracic Society ◽

10.1513/annalsats.201406-250mg ◽

2015 ◽

Vol 12 (Supplement 1) ◽

pp. S75-S75

Author(s):

Yu-chun Lin ◽

Xinguo Jiang ◽

Mark R. Nicolls

Keyword(s):

Chronic Rejection ◽

Lysyl Oxidase ◽

Oxidase Inhibitor ◽

Inhibitor Therapy

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Vasa vasorum formation is associated with rupture of intracranial aneurysms

Journal of Neurosurgery ◽

10.3171/2019.5.jns19405 ◽

2020 ◽

Vol 133 (3) ◽

pp. 789-799 ◽

Cited By ~ 4

Author(s):

Haruka Miyata ◽

Hirohiko Imai ◽

Hirokazu Koseki ◽

Kampei Shimizu ◽

Yu Abekura ◽

...

Keyword(s):

Intracranial Aneurysms ◽

Lysyl Oxidase ◽

Histopathological Examination ◽

Oxidase Inhibitor ◽

Vasa Vasorum ◽

Systemic Hypertension ◽

External Carotid ◽

Anterior Communicating Artery ◽

Sprague Dawley ◽

The Right

OBJECTIVESubarachnoid hemorrhage (SAH) has a poor outcome despite modern advancements in medical care. The development of a novel therapeutic strategy to prevent rupture of intracranial aneurysms (IAs) or a novel diagnostic marker to predict rupture-prone lesions is thus mandatory. Therefore, in the present study, the authors established a rat model in which IAs spontaneously rupture and examined this model to clarify histopathological features associated with rupture of lesions.METHODSFemale Sprague Dawley rats were subjected to bilateral ovariectomy; the ligation of the left common carotid, the right external carotid, and the right pterygopalatine arteries; induced systemic hypertension; and the administration of a lysyl oxidase inhibitor.RESULTSAneurysmal SAH occurred in one-third of manipulated animals and the locations of ruptured IAs were exclusively at a posterior or anterior communicating artery (PCoA/ACoA). Histopathological examination using ruptured IAs, rupture-prone IAs induced at a PCoA or ACoA, and IAs induced at an anterior cerebral artery–olfactory artery bifurcation that never ruptured revealed the formation of vasa vasorum as an event associated with rupture of IAs.CONCLUSIONSThe authors propose the contribution of a structural change in an adventitia, i.e., vasa vasorum formation, to the rupture of IAs. Findings from this study provide important insights about the pathogenesis of IAs.

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