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1.
Nat Commun ; 11(1): 4950, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009377

RESUMO

Necrotizing enterocolitis (NEC) is a devastating disease of premature infants with high mortality rate, indicating the need for precision treatment. NEC is characterized by intestinal inflammation and ischemia, as well derangements in intestinal microcirculation. Remote ischemic conditioning (RIC) has emerged as a promising tool in protecting distant organs against ischemia-induced damage. However, the effectiveness of RIC against NEC is unknown. To address this gap, we aimed to determine the efficacy and mechanism of action of RIC in experimental NEC. NEC was induced in mouse pups between postnatal day (P) 5 and 9. RIC was applied through intermittent occlusion of hind limb blood flow. RIC, when administered in the early stages of disease progression, decreases intestinal injury and prolongs survival. The mechanism of action of RIC involves increasing intestinal perfusion through vasodilation mediated by nitric oxide and hydrogen sulfide. RIC is a viable and non-invasive treatment strategy for NEC.


Assuntos
Enterocolite Necrosante/patologia , Intestinos/irrigação sanguínea , Intestinos/patologia , Isquemia/patologia , Microcirculação , Animais , Enterócitos/patologia , Humanos , Hipóxia , Mucosa Intestinal/patologia , Camundongos Endogâmicos C57BL , Microvilosidades/patologia , Microvilosidades/ultraestrutura
2.
Nat Commun ; 11(1): 3812, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732889

RESUMO

Vascular endothelial cell (EC) dysfunction plays a key role in diabetic complications. This study discovers significant upregulation of Quaking-7 (QKI-7) in iPS cell-derived ECs when exposed to hyperglycemia, and in human iPS-ECs from diabetic patients. QKI-7 is also highly expressed in human coronary arterial ECs from diabetic donors, and on blood vessels from diabetic critical limb ischemia patients undergoing a lower-limb amputation. QKI-7 expression is tightly controlled by RNA splicing factors CUG-BP and hnRNPM through direct binding. QKI-7 upregulation is correlated with disrupted cell barrier, compromised angiogenesis and enhanced monocyte adhesion. RNA immunoprecipitation (RIP) and mRNA-decay assays reveal that QKI-7 binds and promotes mRNA degradation of downstream targets CD144, Neuroligin 1 (NLGN1), and TNF-α-stimulated gene/protein 6 (TSG-6). When hindlimb ischemia is induced in diabetic mice and QKI-7 is knocked-down in vivo in ECs, reperfusion and blood flow recovery are markedly promoted. Manipulation of QKI-7 represents a promising strategy for the treatment of diabetic vascular complications.


Assuntos
Diabetes Mellitus Experimental/patologia , Células Endoteliais/metabolismo , Proteínas de Ligação a RNA/antagonistas & inibidores , Proteínas de Ligação a RNA/metabolismo , Doenças Vasculares/patologia , Animais , Antígenos CD/genética , Aterosclerose/patologia , Caderinas/genética , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular Neuronais/genética , Células Cultivadas , Regulação da Expressão Gênica/genética , Humanos , Hiperglicemia/patologia , Isquemia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Interferência de RNA , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/genética
3.
Gene ; 758: 144973, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32707303

RESUMO

Renal ischemia-reperfusion (rI/R) is a risk factor for acute lung injury (ALI). Alveolar macrophages (AMs) activation mediated by rI/R-induced ALI is one of the pathogeneses associated with the development of ALI. In rI/R, α2-adrenergic receptor agonists have been indicated to be effective in decreasing urea nitrogen concentrations. In this study, we explored the underlying pathogenesis of the clinically obtainable α2-adrenergic receptor agonist dexmedetomidine (DEX) in protecting against rI/R -mediated AMs activation. We incubated AMs with the serum of sham and rI/R rats in the presence or absence of various concentrations of DEX. We used an enzyme-linked immunosorbent assay to detect the secretion levels of GSH, LDH, IL-18, IL-1ß, and HMGB1 in the culture supernatant. We employed real-time polymerase chain reaction to assess the expression of NOX-4 mRNA, and western blotting to observe the protein levels of NOX-4, the NLRP3 inflammasome, AMPK, and eNOS. In addition, we used immunofluorescence to analyze ROS and MMP activity. Incubation of AMs with DEX suppressed rI/R-mediated cellular LDH production and ROS release. DEX also abolished the rI/R-mediated decrease in the activity of GSH and increased the levels of the rI/R-related NADPH oxidase protein NOX-4. Furthermore, DEX reduced the amelioration of the mitochondrial potential induced by rI/R. Our study showed that DEX inhibits rI/R-mediated levels of the NLRP3 inflammasome proteins ASC, NLRP3, HMGB1 and p20, and ameliorates rI/R-mediated AMPK signaling inactivation. Therefore, DEX reduces the levels of two mediators that are activated by the NLRP3 inflammasome: IL-18 and IL-1ß. Finally, our study established that DEX mitigates the rI/R-mediated decrease in eNOS, demonstrating its protective functions against AMs activation. In conclusion, our study demonstrated that the protective action of DEX in AMs is induced through amelioration of HMGB1-NLRP3 inflammasome-AMPK signaling. Our results suggest that the anesthetic reagent DEX exerts beneficial effects to ameliorate rI/R-induced ALI.


Assuntos
Lesão Renal Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/prevenção & controle , Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Dexmedetomidina/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Proteína HMGB1/metabolismo , Isquemia/patologia , Macrófagos Alveolares/patologia , NADPH Oxidase 4/biossíntese , NADPH Oxidase 4/genética , Óxido Nítrico Sintase Tipo III/metabolismo , RNA Mensageiro/genética , Ratos , Reação em Cadeia da Polimerase em Tempo Real
4.
Mol Med ; 26(1): 69, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641037

RESUMO

BACKGROUND: We previously showed that the autophagy inhibitor chloroquine (CQ) increases inflammatory cleaved caspase-1 activity in myocytes, and that caspase-1/11 is protective in sterile liver injury. However, the role of caspase-1/11 in the recovery of muscle from ischemia caused by peripheral arterial disease is unknown. We hypothesized that caspase-1/11 mediates recovery in muscle via effects on autophagy and this is modulated by CQ. METHODS: C57Bl/6 J (WT) and caspase-1/11 double-knockout (KO) mice underwent femoral artery ligation (a model of hind-limb ischemia) with or without CQ (50 mg/kg IP every 2nd day). CQ effects on autophagosome formation, microtubule associated protein 1A/1B-light chain 3 (LC3), and caspase-1 expression was measured using electron microscopy and immunofluorescence. Laser Doppler perfusion imaging documented perfusion every 7 days. After 21 days, in situ physiologic testing in tibialis anterior muscle assessed peak force contraction, and myocyte size and fibrosis was also measured. Muscle satellite cell (MuSC) oxygen consumption rate (OCR) and extracellular acidification rate was measured. Caspase-1 and glycolytic enzyme expression was detected by Western blot. RESULTS: CQ increased autophagosomes, LC3 consolidation, total caspase-1 expression and cleaved caspase-1 in muscle. Perfusion, fibrosis, myofiber regeneration, muscle contraction, MuSC fusion, OCR, ECAR and glycolytic enzyme expression was variably affected by CQ depending on presence of caspase-1/11. CQ decreased perfusion recovery, fibrosis and myofiber size in WT but not caspase-1/11KO mice. CQ diminished peak force in whole muscle, and myocyte fusion in MuSC and these effects were exacerbated in caspase-1/11KO mice. CQ reductions in maximal respiration and ATP production were reduced in caspase-1/11KO mice. Caspase-1/11KO MuSC had significant increases in protein kinase isoforms and aldolase with decreased ECAR. CONCLUSION: Caspase-1/11 signaling affects the response to ischemia in muscle and effects are variably modulated by CQ. This may be critically important for disease treated with CQ and its derivatives, including novel viral diseases (e.g. COVID-19) that are expected to affect patients with comorbidities like cardiovascular disease.


Assuntos
Caspase 1/metabolismo , Caspases Iniciadoras/metabolismo , Cloroquina/farmacologia , Infecções por Coronavirus/patologia , Isquemia/patologia , Músculo Esquelético/patologia , Pneumonia Viral/patologia , Animais , Autofagossomos/metabolismo , Autofagia/efeitos dos fármacos , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Glicólise/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/metabolismo , Células Musculares/metabolismo , Desenvolvimento Muscular , Músculo Esquelético/metabolismo , Neovascularização Fisiológica , Fosforilação Oxidativa , Pandemias , Doença Arterial Periférica/patologia , Pneumonia Viral/tratamento farmacológico , Regeneração , Transdução de Sinais
5.
Arterioscler Thromb Vasc Biol ; 40(9): 1982-1989, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32673526

RESUMO

Atherosclerosis is a systemic disease that involves multiple vascular beds. The pathological characteristics and clinical presentation, however, vary among the different vascular territories. Acute coronary syndrome is a relatively common manifestation of coronary atherosclerotic disease, wherein the thrombosis occurs secondary to disruption (65%-75%) and erosion (25%-35%) of the fibrous caps of atheromatous plaques. The plaques associated with plaque rupture have large necrotic cores and thin and inflamed fibrous caps. However, the pathological manifestations of peripheral artery disease result from thrombosis regardless of the extent of atherosclerosis. Approximately 75% of peripheral arteries with significant stenosis demonstrate presence of thrombi, of which two-thirds have thrombi associated with insignificant atherosclerosis. The presence of obliterative thrombi in peripheral arteries of patients with critical limb ischemia in the absence of coronary artery-like lesions suggests a locally thrombogenic or remotely embolic basis of disease. Extensive calcification of the medial vascular layer is commonly observed. In this review, we have described and compared the pathological basis of coronary and peripheral artery disease in patients with acute coronary syndrome and critical limb ischemia. It is expected that pathogenetic characterization would allow for definition of strategic targets for superior management of peripheral artery disease.


Assuntos
Síndrome Coronariana Aguda/patologia , Artérias/patologia , Doença da Artéria Coronariana/patologia , Isquemia/patologia , Doença Arterial Periférica/patologia , Placa Aterosclerótica , Trombose/patologia , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/epidemiologia , Artérias/efeitos dos fármacos , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/epidemiologia , Vasos Coronários/patologia , Estado Terminal , Progressão da Doença , Fibrinolíticos/uso terapêutico , Fibrose , Humanos , Doença Arterial Periférica/tratamento farmacológico , Doença Arterial Periférica/epidemiologia , Prognóstico , Ruptura Espontânea , Trombose/tratamento farmacológico , Trombose/epidemiologia
6.
Acta Cir Bras ; 35(5): e202000503, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32578671

RESUMO

PURPOSE: To investigate the effect of hyperbaric oxygen therapy on colonic anastomosis healing with and without ischemia in rats. METHODS: Forty female rats underwent segmental resection of 1 cm of the left colon followed by end-to-end anastomosis. They were randomly assigned to four groups (n=10 each), a sham group; two groups were submitted to Hyperbaric Oxygen therapy (HBOT) with and without induced ischemia and the induced ischemia group without HBOT. The HBOT protocol evaluated was 100% O2 at 2.4 Atmosphere absolute pressure (ATA) for 60 minutes, two sessions before as a preconditioning protocol and three sessions after the operation. Clinical course and mortality were monitored during all experiment and on the day of euthanasia on the fourth day after laparotomy. Macroscopic appearance of the abdominal cavity were assessed and samples for breaking strength of the anastomosis and histopathological parameters were collected. RESULTS: There was no statistically significant difference in mortality or anastomosis leak between the four experimental groups. Anastomosis breaking strength was similar across groups. CONCLUSION: The HBOT protocol tested herein at 2.4 ATA did not affect histopathological and biomechanical parameters of colonic anastomotic healing, neither the clinical outcomes death and anastomosis leak on the fourth day after laparotomy.


Assuntos
Colo/irrigação sanguínea , Colo/cirurgia , Oxigenação Hiperbárica/métodos , Isquemia/patologia , Precondicionamento Isquêmico/métodos , Cicatrização , Anastomose Cirúrgica , Animais , Colo/patologia , Feminino , Isquemia/prevenção & controle , Período Pós-Operatório , Ratos Endogâmicos Lew , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
7.
Proc Natl Acad Sci U S A ; 117(25): 14354-14364, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513697

RESUMO

Ischemic injury initiates a sterile inflammatory response that ultimately participates in the repair and recovery of tissue perfusion. Macrophages are required for perfusion recovery during ischemia, in part because they produce growth factors that aid in vascular remodeling. The input signals governing this pro-revascularization phenotype remain of interest. Here we found that hindlimb ischemia increases levels of resolvin D1 (RvD1), an inflammation-resolving lipid mediator that targets macrophages via its receptor, ALX/FPR2. Exogenous RvD1 enhances perfusion recovery during ischemia, and mice deficient in Alx/Fpr2 have an endogenous defect in this process. Mechanistically, RNA sequencing revealed that RvD1 induces a transcriptional program in macrophages characteristic of a pro-revascularization phenotype. Vascularization of ischemic skeletal muscle, as well as cutaneous wounds, is impaired in mice with myeloid-specific deficiency of Alx/Fpr2, and this is associated with altered expression of pro-revascularization genes in skeletal muscle and macrophages isolated from skeletal muscle. Collectively, these results uncover a role of ALX/FPR2 in revascularization that may be amenable to therapeutic targeting in diseases associated with altered tissue perfusion and repair.


Assuntos
Ácidos Docosa-Hexaenoicos/metabolismo , Isquemia/imunologia , Neovascularização Fisiológica/imunologia , Receptores de Formil Peptídeo/metabolismo , Receptores de Lipoxinas/metabolismo , Cicatrização/imunologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Humanos , Isquemia/patologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Knockout , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/imunologia , Músculo Esquelético/patologia , Cultura Primária de Células , RNA-Seq , Receptores de Formil Peptídeo/genética , Receptores de Lipoxinas/genética , Transdução de Sinais/imunologia , Pele/irrigação sanguínea , Pele/imunologia , Pele/lesões , Pele/patologia , Transcrição Genética/imunologia
8.
PLoS One ; 15(6): e0235362, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32584895

RESUMO

OBJECTIVE: Cardiovascular disease is a leading cause of death worldwide. Obesity-related metabolic disorders including dyslipidemia cause impaired collateralization under ischemic conditions, thereby resulting in exacerbated cardiovascular dysfunction. Pemafibrate is a novel selective PPARα modulator, which has been reported to improve atherogenic dyslipidemia, in particular, hypertriglyceridemia and low HDL-cholesterol. Here, we investigated whether pemafibrate modulates the revascularization process in a mouse model of hindlimb ischemia. METHODS AND RESULTS: Male wild-type (WT) mice were randomly assigned to two groups, normal diet or pemafibrate admixture diet from the ages of 6 weeks. After 4 weeks, mice were subjected to unilateral hindlimb surgery to remove the left femoral artery and vein. Pemafibrate treatment enhanced blood flow recovery and capillary formation in ischemic limbs of mice, which was accompanied by enhanced phosphorylation of endothelial nitric oxide synthase (eNOS). Treatment of cultured endothelial cells with pemafibrate resulted in increased network formation and migratory activity, which were blocked by pretreatment with the NOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME). Pemafibrate treatment also increased plasma levels of the PPARα-regulated gene, fibroblast growth factor (FGF) 21 in WT mice. Systemic administration of adenoviral vectors expressing FGF21 (Ad-FGF21) to WT mice enhanced blood flow recovery, capillary density and eNOS phosphorylation in ischemic limbs. Treatment of cultured endothelial cells with FGF21 protein led to increases in endothelial cell network formation and migration, which were canceled by pretreatment with L-NAME. Furthermore, administration of pemafibrate or Ad-FGF21 had no effects on blood flow in ischemic limbs in eNOS-deficient mice. CONCLUSION: These data suggest that pemafibrate can promote revascularization in response to ischemia, at least in part, through direct and FGF21-mediated modulation of endothelial cell function. Thus, pemafibrate could be a potentially beneficial drug for ischemic vascular disease.


Assuntos
Benzoxazóis/farmacologia , Butiratos/farmacologia , Isquemia/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Fatores de Crescimento de Fibroblastos/sangue , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Membro Posterior/irrigação sanguínea , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Knockout , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , PPAR alfa/química , PPAR alfa/metabolismo , Fosforilação/efeitos dos fármacos
9.
Acta Cir Bras ; 35(2): e202000205, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428061

RESUMO

Purpose To investigate the effects of induction of selective liver hypothermia in a rodent model. Methods Seven male Wistar rats were subjected to 90 minutes of partial 70% liver ischemia and topic liver 26°C hypothermia (H group). Other seven male Wistar rats were subjected to 90 minutes of partial 70% normothermic liver ischemia (N group). Five additional rats underwent a midline incision and section of liver ligaments under normothermic conditions and without any liver ischemia (sham group). All animals were sacrificed 24-h after reperfusion, and livers were sampled for analyses. Pathology sections were scored for sinusoidal congestion, ballooning, hepatocelllular necrosis and the presence of neutrophilic infiltrates. Results At the end of the experiment, liver tissue expressions of TNF-ɑ, IL-1ß, iNOS and TNF-ɑ/IL-10 ratio were significantly reduced in the H group compared to N group, whereas IL-10 and eNOS were significantly increased in H group. Histopathological injury scores revealed a significant decrease in ischemia/reperfusion (I/R) injuries in H group. Conclusion Selective liver hypothermia prevented I/R injury by inhibiting the release of inflammatory cytokines, preserves microcirculation, prevents hepatocellular necrosis and leukocyte infiltration, allowing maintenance of the liver architecture.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Hipotermia Induzida/métodos , Fígado/irrigação sanguínea , Traumatismo por Reperfusão/prevenção & controle , Lesão Pulmonar Aguda/patologia , Animais , Temperatura Corporal , Citocinas/metabolismo , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Isquemia/patologia , Fígado/patologia , Masculino , Necrose/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Fator de Necrose Tumoral alfa
10.
PLoS One ; 15(5): e0233109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32437461

RESUMO

Normalisation to standard reference gene(s) is essential for quantitative real-time polymerase chain reaction (RT-qPCR) to obtain reproducible and comparable results of a gene of interest (GOI) between subjects and under varying experimental conditions. There is limited evidence to support selection of the commonly used reference genes in rat ischaemic and toxicological kidney models. Employing these models, we determined the most stable reference genes by comparing 4 standard methods (NormFinder, qBase+, BestKeeper and comparative ΔCq) and developed a new 3-way linear mixed-effects model for evaluation of reference gene stability. This new technique utilises the intra-class correlation coefficient as the stability measure for multiple continuous and categorical covariates when determining the optimum normalisation factor. The model also determines confidence intervals for each candidate normalisation gene to facilitate selection and allow sample size calculation for designing experiments to identify reference genes. Of the 10 candidate reference genes tested, the geometric mean of polyadenylate-binding nuclear protein 1 (PABPN1) and beta-actin (ACTB) was the most stable reference combination. In contrast, commonly used ribosomal 18S and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) were the most unstable. We compared the use of PABPN1×ACTB and 2 commonly used genes 18S and GAPDH on the expression of 4 genes of interest know to vary after renal injury and expressed by different kidney cell types (KIM-1, HIF1α, TGFß1 and PECAM1). The less stable reference genes gave varying patterns of GOI expression in contrast to the use of the least unstable reference PABPN1×ACTB combination; this improved detection of differences in gene expression between experimental groups. Reduced within-group variation of the now more accurately normalised GOI may allow for reduced experimental group size particularly for comparison between various models. This objective selection of stable reference genes increased the reliability of comparisons within and between experimental groups.


Assuntos
Regulação da Expressão Gênica , Isquemia/metabolismo , Nefropatias/metabolismo , Rim/irrigação sanguínea , Rim/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Actinas/biossíntese , Animais , Isquemia/patologia , Rim/patologia , Nefropatias/patologia , Proteína I de Ligação a Poli(A)/biossíntese , RNA Ribossômico 18S/biossíntese , Ratos , Padrões de Referência
11.
Am J Pathol ; 190(8): 1723-1734, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32389572

RESUMO

Retinal ischemic events, which result from occlusion of the ocular vasculature share similar causes as those for central nervous system stroke and are among the most common cause of acute and irreversible vision loss in elderly patients. Currently, there is no established treatment, and the condition often leaves patients with seriously impaired vision or blindness. The immune system, particularly T-cell-mediated responses, is thought to be intricately involved, but the exact roles remain elusive. We found that acute ischemia-reperfusion injury to the retina induced a prolonged phase of retinal ganglion cell loss that continued to progress during 8 weeks after the procedure. This phase was accompanied by microglial activation and CD4+ T-cell infiltration into the retina. Adoptive transfer of CD4+ T cells isolated from diseased mice exacerbated retinal ganglion cell loss in mice with retinal reperfusion damage. On the other hand, T-cell deficiency or administration of T-cell or interferon-γ-neutralizing antibody attenuated retinal ganglion cell degeneration and retinal function loss after injury. These findings demonstrate a crucial role for T-cell-mediated responses in the pathogenesis of neural ischemia. These findings point to novel therapeutic targets of limiting or preventing neuron and function loss for currently untreatable conditions of optic neuropathy and/or central nervous system ischemic stroke.


Assuntos
Linfócitos T CD4-Positivos/patologia , Isquemia/patologia , Retina/patologia , Degeneração Retiniana/patologia , Doenças Retinianas/patologia , Vasos Retinianos/patologia , Transferência Adotiva , Animais , Modelos Animais de Doenças , Progressão da Doença , Camundongos , Células Ganglionares da Retina/patologia
12.
Nat Commun ; 11(1): 2591, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444641

RESUMO

The intestine is a highly dynamic environment that requires tight control of the various inputs to maintain homeostasis and allow for proper responses to injury. It was recently found that the stem cell niche and epithelium is regenerated after injury by de-differentiated adult cells, through a process that gives rise to Sca1+ fetal-like cells and is driven by a transient population of Clu+ revival stem cells (revSCs). However, the molecular mechanisms that regulate this dynamic process have not been fully defined. Here we show that TNFAIP8 (also known as TIPE0) is a regulator of intestinal homeostasis that is vital for proper regeneration. TIPE0 functions through inhibiting basal Akt activation by the commensal microbiota via modulating membrane phospholipid abundance. Loss of TIPE0 in mice results in injury-resistant enterocytes, that are hyperproliferative, yet have regenerative deficits and are shifted towards a de-differentiated state. Tipe0-/- enterocytes show basal induction of the Clu+ regenerative program and a fetal gene expression signature marked by Sca1, but upon injury are unable to generate Sca-1+/Clu+ revSCs and could not regenerate the epithelium. This work demonstrates the role of TIPE0 in regulating the dynamic signaling that determines the injury response and enables intestinal epithelial cell regenerative plasticity.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Microbioma Gastrointestinal/fisiologia , Intestinos/citologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Ataxina-1/metabolismo , Diferenciação Celular , Colite/induzido quimicamente , Colite/patologia , Enterócitos/patologia , Feminino , Técnicas de Silenciamento de Genes , Homeostase , Intestinos/irrigação sanguínea , Intestinos/patologia , Intestinos/efeitos da radiação , Isquemia/genética , Isquemia/patologia , Antígenos Comuns de Leucócito/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Lesões Experimentais por Radiação/patologia , Regeneração/fisiologia , Transdução de Sinais , Nicho de Células-Tronco , Células-Tronco/metabolismo
14.
Rev. chil. cardiol ; 39(1): 24-33, abr. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1115446

RESUMO

INTRODUCCIÓN: Los ratones SR-B1 KO/ApoER6 1h/h que son alimentados con una dieta rica en grasas saturadas, desarrollan enfermedad coronaria aterosclerótica severa, complicaciones isquémicas e insuficiencia cardíaca, con alta mortalidad. Los estudios con este modelo se han enfocado fundamentalmente en la enfermedad coronaria y menos en el remodelado cardíaco. El OBJETIVO del trabajo ha sido caracterizar el remodelado miocárdico, evaluar la evolución temporal de la función ventricular izquierda y la sobrevida asociada a enfermedad cardíaca por ateromatosis. MÉTODO: Ratones homocigotos SR-B1 KO/ApoER6 1h/h fueron alimentados por 8 semanas con dieta aterogénica o dieta normal y se comparó la sobrevida en ambos grupos. A las 4 semanas se realizó un ecocardiograma bidimensional. En los ratones eutanasiados se evaluó en la pared cardíaca fibrosis miocárdica y tamaño de los cardiomiocitos por morfometría, apoptosis con técnica de TUNEL e infiltración por células inflamatorias mononucleares (ED1) por inmunohistoquímica. RESULTADOS: En el grupo que recibió dieta aterogénica la sobrevida se redujo en 46,7% (p < 0.001), debido a muerte súbita y a falla cardíaca progresiva. En este grupo, a las 4 semanas se observó dilatación de cavidades izquierdas y disminución de la fracción de eyección del ventrículo izquierdo en comparación con el grupo control (79,3 ± 1,3% vs 66 ± 3,7%, p<0,01). También se observó aumento de la masa cardíaca relativa de 2.1 veces (p<0,001) y del peso pulmonar relativo en 80% (p<0,001), sin cambios en las dimensiones de los cardiomiocitos. En el miocardio de los ratones que recibieron dieta aterogénica hubo un aumento de la fibrosis cardíaca de 7.9 veces (p < 0.01) y del número de cardiomiocitos apoptóticos en 55.9 veces (p < 0.01), junto a un aumento del número de células inflamatorias mononucleares ED1. CONCLUSIONES: En el modelo de falla cardíaca severa de etiología isquémica con alta mortalidad en el ratón homocigoto SR-B1 KO/ApoER6 1h/h sometido a una dieta aterogénica, con falla cardíaca izquierda por disfunción sistólica, el remodelado patológico del miocardio está dado fundamentalmente por apoptosis y fibrosis. También se observa un aumento discreto de macrófagos en la pared cardíaca. Es posible que el edema parietal también pueda ser un mecanismo de remodelado relevante en este modelo.


Abstract: SR-B1 KO/ApoER6 1h/h mice fed a high saturated fat diet develop severe coronary atheromatosis, and cardiac failure with a high mortality rate. Cardiac remodeling under these conditions has not been well studied. AIM: To evaluate the time course of left ventricular function, cardiac remodeling and survival associated to the administration of an atherogenic diet. METHOD: Homozygote SR-B1 KO/ApoER6 1h/h mice received an atherogenic diet for 8 weeks. Mice receiving a normal diet served as controls. Survival rate, myocardial fibrosis, cardiomyocyte size, apoptosis and infiltration by inflammatory or mononuclear cells were compared between groups. A TUNEL technique was used to evaluate apoptosis. RESULTS: A 46.7% survival reduction compared to controls was observed in the experimental group (p<0.01), due to left ventricular and atrial dilatation associated to a decrease in ejection fraction (79,3 ± 1,3% vs 66 ± 3,7%, p<0,01, respectively). Also, an increased cardiac weight, 2.6 times greater was observed in the experimental group, compared to controls. Mice receiving the atherogenic diet showed an 80% increased lung weight. There was no evident change in cardiomyocytes, but there was more (7.9 times) cardiac fibrosis (p<0.01) and 55.9 times more apoptotic cells. (p<0.01), along with a greater number of inflammatory cells and ED1 mononuclear cells. CONCLUSION: Mice receiving an atherogenic diet develop heart failure and reduced survival rate. This is associated with cardiac remodeling with underlying apoptosis an ventricular wall fibrosis. It is posible that wall edema might contribute to the observed cardiac remodeling.


Assuntos
Animais , Camundongos , Remodelação Ventricular , Dieta Aterogênica , Insuficiência Cardíaca/etiologia , Hiperlipidemias/patologia , Isquemia/etiologia , Fibrose , Análise de Sobrevida , Função Ventricular Esquerda , Apoptose , Camundongos Knockout , Disfunção Ventricular , Modelos Animais de Doenças , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/patologia , Isquemia/fisiopatologia , Isquemia/mortalidade , Isquemia/patologia
15.
Nat Commun ; 11(1): 1195, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32139672

RESUMO

Here, we report that the functionality of vascular progenitors (VP) generated from normal and disease-primed conventional human induced pluripotent stem cells (hiPSC) can be significantly improved by reversion to a tankyrase inhibitor-regulated human naïve epiblast-like pluripotent state. Naïve diabetic vascular progenitors (N-DVP) differentiated from patient-specific naïve diabetic hiPSC (N-DhiPSC) possessed higher vascular functionality, maintained greater genomic stability, harbored decreased lineage-primed gene expression, and were more efficient in migrating to and re-vascularizing the deep neural layers of the ischemic retina than isogenic diabetic vascular progenitors (DVP). These findings suggest that reprogramming to a stable naïve human pluripotent stem cell state may effectively erase dysfunctional epigenetic donor cell memory or disease-associated aberrations in patient-specific hiPSC. More broadly, tankyrase inhibitor-regulated naïve hiPSC (N-hiPSC) represent a class of human stem cells with high epigenetic plasticity, improved multi-lineage functionality, and potentially high impact for regenerative medicine.


Assuntos
Vasos Sanguíneos/patologia , Diabetes Mellitus/patologia , Células-Tronco Pluripotentes Induzidas/patologia , Isquemia/terapia , Retina/patologia , Células-Tronco/patologia , Tanquirases/antagonistas & inibidores , Adulto , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Linhagem da Célula/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Dano ao DNA , Inibidores Enzimáticos/farmacologia , Epigênese Genética/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Código das Histonas , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Isquemia/patologia , Camundongos , Organoides/efeitos dos fármacos , Organoides/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Regiões Promotoras Genéticas/genética , Células-Tronco/efeitos dos fármacos , Células-Tronco/ultraestrutura , Tanquirases/metabolismo , Teratoma/patologia , Transcrição Genética/efeitos dos fármacos
16.
PLoS One ; 15(3): e0229566, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32155167

RESUMO

In porcine kidney auto-transplant models, red blood cells (RBCs) are required for ex-vivo normothermic machine perfusion (NMP). As large quantities of RBCs are needed for NMP, utilising autologous RBCs would imply lethal exsanguination of the pig that is donor and recipient-to-be in the same experiment. The purpose of this study was to determine if an isolated porcine kidney can also be perfused with allogeneic porcine or human RBCs instead. Porcine kidneys, autologous and allogeneic blood were obtained from a local slaughterhouse. Human RBCs (O-pos), were provided by our transfusion laboratory. Warm ischaemia time was standardised at 20 minutes and subsequent hypothermic machine perfusion lasted 1.5-2.5 hours. Next, kidneys underwent NMP at 37°C during 7 hours with Williams' Medium E and washed, leukocyte depleted RBCs of either autologous, allogeneic, or human origin (n = 5 per group). During perfusion all kidneys were functional and produced urine. No macroscopic adverse reactions were observed. Creatinine clearance during NMP was significantly higher in the human RBC group in comparison with the allogeneic group (P = 0.049) but not compared to the autologous group. The concentration of albumin in the urine was significantly higher in the human RBC group (P <0.001) compared to the autologous and allogeneic RBC group. Injury marker aspartate aminotransferase was significantly higher in the human RBC group in comparison with the allogeneic group (P = 0.040) but not in comparison with the autologous group. Renal histology revealed glomerular and tubular damage in all groups. Signs of pathological hyperfiltration and microvascular injury were only observed in the human RBC group. In conclusion, perfusion of porcine kidneys with RBCs of different origin proved technically feasible. However, laboratory analysis and histology revealed more damage in the human RBC group compared to the other two groups. These results indicate that the use of allogeneic RBCs is preferable to human RBCs in a situation where autologous RBCs cannot be used for NMP.


Assuntos
Transplante de Rim/métodos , Perfusão/métodos , Transplante Homólogo/métodos , Animais , Contagem de Eritrócitos , Transfusão de Eritrócitos/métodos , Eritrócitos/fisiologia , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Isquemia/patologia , Rim/patologia , Glomérulos Renais , Modelos Animais , Preservação de Órgãos/métodos , Suínos , Doadores de Tecidos , Isquemia Quente
17.
Med Sci (Paris) ; 36(2): 147-152, 2020 Feb.
Artigo em Francês | MEDLINE | ID: mdl-32129751

RESUMO

Ischemia is one of the major concerns of clinicians who are constantly confronted with it, both in surgical and pathological aspects. The consequences of ischemic stress are dramatic and can lead to organic, motor or cognitive disabilities. Currently, there is no identified specific molecular target whose targeting could be beneficial in this area. The drosophila melanogaster fly, used as a model animal, has made it possible to highlight a major advance by allowing the identification of a completely new pharmacological target whose inhibition significantly increases tolerance to hypoxia. Applied to a preclinical model of renal transplantation, this new approach significantly improves the functional recovery of the graft in the long term. This mini-synthesis retraces the steps that made it possible to transfer to higher mammals a concept highlighted in Drosophila that clearly shows, beyond basic research, the contribution that a model organism can make to the clinic.


Assuntos
Modelos Animais de Doenças , Drosophila melanogaster , Isquemia/terapia , Animais , Humanos , Isquemia/patologia , Mamíferos , Pesquisa Médica Translacional
18.
Nat Commun ; 11(1): 615, 2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-32001693

RESUMO

Angiogenesis induction into damaged sites has long been an unresolved issue. Local treatment with pro-angiogenic molecules has been the most common approach. However, this approach has critical side effects including inflammatory coupling, tumorous vascular activation, and off-target circulation. Here, the concept that a structure can guide desirable biological function is applied to physically engineer three-dimensional channel networks in implant sites, without any therapeutic treatment. Microchannel networks are generated in a gelatin hydrogel to overcome the diffusion limit of nutrients and oxygen three-dimensionally. Hydrogel implantation in mouse and porcine models of hindlimb ischemia rescues severely damaged tissues by the ingrowth of neighboring host vessels with microchannel perfusion. This effect is guided by microchannel size-specific regenerative macrophage polarization with the consequent functional recovery of endothelial cells. Multiple-site implantation reveals hypoxia and neighboring vessels as major causative factors of the beneficial function. This technique may contribute to the development of therapeutics for hypoxia/inflammatory-related diseases.


Assuntos
Indutores da Angiogênese/efeitos adversos , Gelatina/química , Gelatina/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Isquemia/terapia , Animais , Modelos Animais de Doenças , Células Endoteliais/patologia , Desenho de Equipamento , Feminino , Membro Posterior/irrigação sanguínea , Membro Posterior/diagnóstico por imagem , Membro Posterior/patologia , Hidrogéis/uso terapêutico , Hipóxia , Isquemia/diagnóstico por imagem , Isquemia/patologia , Macrófagos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Fisiológica/fisiologia , Doenças Vasculares Periféricas/patologia , Doenças Vasculares Periféricas/terapia , Próteses e Implantes , Suínos , Cicatrização
19.
Pain Physician ; 23(1): E51-E60, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32013288

RESUMO

BACKGROUND: The success rate for the production of animal models of chronic postischemia pain (CPIP) using an O-ring has yet to be improved in the study of complex regional pain syndrome-type I (CRPS-I), and producing a CPIP model is challenging, especially for mice. OBJECTIVES: We devised a new CPIP model with a higher success rate that induces ischemia for 3 hours by tying the hind limbs of mice with a rubber band, followed by reperfusion. STUDY DESIGN: A randomized, controlled animal trial. METHODS: Twenty-two male C57BL/6 mice were divided into a sham (n = 6), a ring (n = 8), and a tie group (n = 8). Anesthesia was induced using isoflurane. A precut O-ring was mounted on the upper left ankle in the sham group. A tight-fitting O-ring and a push-pull gauge manometer were mounted at the same location in the ring and tie groups, respectively. Reperfusion was induced 3 hours later. The thickness and circumference of the hind paws were measured before ischemia induction. Measurements were repeated 10 days after reperfusion. Mechanical allodynia was measured with a von Frey filament until 12 weeks after reperfusion. RESULTS: The new tie model required 5 additional days until the onset of allodynia compared with the existing CPIP O-ring model. However, the successful induction rate of CPIP was higher in the tie group than in the ring group, and allodynia was maintained for over 30 days in the tie group. The ring and tie groups exhibited significantly high levels of tumor necrosis factor-alpha than those in the sham group. LIMITATIONS: First, we did not evaluate hyperalgesia, cold or heat allodynia. Second, we did not measure blood levels of inflammatory or antiinflammatory cytokines, and research on oxidative stress biomarkers such as isoprostane, 8-hydroxy-2'-deoxyguanosine (a marker of DNA oxidative damage), and malondialdehyde was not performed. CONCLUSIONS: The new CPIP tie model has a higher rate of successful induction than existing O-ring models for mice, with longer duration of mechanical allodynia. The model may reduce the number of animals sacrificed in CRPS-I research and could be useful for studying long-term effects of drugs. KEY WORDS: CPIP, mouse, O-ring, rubber band, reperfusion, allodynia, hyperalgesia.


Assuntos
Síndromes da Dor Regional Complexa/patologia , Síndromes da Dor Regional Complexa/fisiopatologia , Modelos Animais de Doenças , Membro Posterior/irrigação sanguínea , Isquemia/patologia , Isquemia/fisiopatologia , Animais , Dor Crônica/patologia , Dor Crônica/fisiopatologia , Constrição Patológica/sangue , Constrição Patológica/patologia , Hiperalgesia/patologia , Hiperalgesia/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória
20.
JACC Cardiovasc Interv ; 13(4): 418-427, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32081234

RESUMO

OBJECTIVES: The objective of this study was to comprehensively evaluate the pathology of acute and chronic femoral stenting in symptomatic atherosclerotic patients and to understand the causes of stent failure (SF) using multimodality imaging including micro-computed tomography. BACKGROUND: Although the pathology of coronary stenting has been well studied, the pathology of lower extremity femoral stenting remains poorly understood. METHODS: Twelve stented femoral lesions removed at surgery (n = 10) and at autopsy (n = 2) were obtained from 10 patients (median age 74 years; interquartile range [IQR]: 66 to 82 years) with histories of peripheral artery disease (critical limb ischemia in 7) (7 men and 3 women). All specimens underwent radiography, micro-computed tomography, and histological assessment. RESULTS: The median duration of implantation was 150 days (IQR: 30 to 365 days), the median stent diameter was 5.90 mm (IQR: 5.44 to 7.16 mm), and the median stent length was 39.5 mm (IQR: 27 to 107.5 mm). Of the 12 stented lesions, 2 had drug-eluting stents, and 10 had bare-metal stents. SF was observed in 8 of 12 lesions. The major cause of SF was acute thrombosis (6 of 8), but causes varied (delayed healing, stent underexpansion, false lumen stenting, and fracture), and 2 had restenosis. Stent fractures were observed in 3 cases by micro-computed tomography. Both drug-eluting stents, implanted for >1 year, showed delayed healing with circumferential peristrut fibrin deposition and SF. CONCLUSIONS: This histological study is the first to examine the pathological cause of SF. Stent thrombosis was the major cause of SF. Delayed healing was a common feature of bare-metal stents implanted for <90 days, while all drug-eluting stents, despite implantation duration >1 year, showed delayed healing.


Assuntos
Procedimentos Endovasculares/instrumentação , Artéria Femoral , Isquemia/terapia , Imagem Multimodal , Doença Arterial Periférica/terapia , Falha de Prótese , Stents , Calcificação Vascular/terapia , Idoso , Idoso de 80 Anos ou mais , Remoção de Dispositivo , Procedimentos Endovasculares/efeitos adversos , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/patologia , Artéria Femoral/cirurgia , Humanos , Isquemia/diagnóstico por imagem , Isquemia/patologia , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/patologia , Valor Preditivo dos Testes , Trombose/diagnóstico por imagem , Trombose/patologia , Fatores de Tempo , Resultado do Tratamento , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/patologia , Cicatrização , Microtomografia por Raio-X
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