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1.
FASEB J ; 36(11): e22613, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36250916

RESUMO

Intestinal failure (IF) occurs when intestinal surface area or function is not sufficient to support digestion and nutrient absorption. Human intestinal organoid (HIO)-derived tissue-engineered intestine is a potential cure for IF. Research to date has demonstrated successful HIO transplantation (tHIO) into mice with significant in vivo maturation. An area lacking in the literature is exploration of murine host sex as a biological variable (SABV) in tHIO function. In this study, we investigate murine host SABV in tHIO epithelial barrier function and muscle contractility. HIOs were generated in vitro and transplanted into nonobese diabetic, severe combined immunodeficiency gamma chain deficient male and female mice. tHIOs were harvested after 8-12 weeks in vivo. Reverse transcriptase polymerase chain reaction and immunohistochemistry were conducted to compare tight junctions and contractility-related markers in tHIOs. An Ussing chamber and contractility apparatus were used to evaluate tHIO epithelial barrier and muscle contractile function, respectively. The expression and morphology of tight junction and contractility-related markers from tHIOs in male and female murine hosts is not significantly different. Epithelial barrier function as measured by transepithelial resistance, short circuit current, and fluorescein isothiocyanate-dextran permeability is no different in tHIOs from male and female hosts, although these results may be limited by HIO epithelial immaturity and a short flux time. Muscle contractility as measured by total contractile activity, amplitude, frequency, and tension is not significantly different in tHIOs from male and female hosts. The data suggest that murine host sex may not be a significant biological variable influencing tHIO function, specifically epithelial barrier maintenance and muscle contractility, though limitations exist in our model.


Assuntos
Dextranos , Organoides , Animais , Dextranos/metabolismo , Feminino , Humanos , Mucosa Intestinal/metabolismo , Intestinos , Masculino , Camundongos , Músculos/metabolismo , Organoides/metabolismo , Permeabilidade , Junções Íntimas/metabolismo
2.
Stem Cells ; 39(3): 358-370, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33368792

RESUMO

The inflammatory response after traumatic brain injury (TBI) can lead to significant secondary brain injury and chronic inflammation within the central nervous system. Cell therapies, including mesenchymal stromal cells (MSC), have led to improvements in animal models of TBI and are under investigation in human trials. One potential mechanism for the therapeutic potential of MSC is their ability to augment the endogenous response of immune suppressive regulatory T cells (Treg). We have recently shown that infusion of human cord blood Treg decreased chronic microgliosis after TBI and altered the systemic immune response in a rodent model. These cells likely use both overlapping and distinct mechanisms to modulate the immune system; therefore, combining Treg and MSC as a combination therapy may confer therapeutic benefit over either monotherapy. However, investigation of Treg + MSC combination therapy in TBI is lacking. In this study, we compared the ability MSC + Treg combination therapy, as well as MSC and Treg monotherapies, to inhibit the neuroinflammatory response to TBI in vivo and in vitro. Treg + MSC combination therapy demonstrated increased potency to reduce the neuro- and peripheral inflammatory response compared to monotherapy; furthermore, the timing of infusion proved to be a significant variable in the efficacy of both MSC monotherapy and Treg + MSC combination therapy in vivo and in vitro.


Assuntos
Lesões Encefálicas Traumáticas/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/imunologia , Linfócitos T Reguladores/imunologia , Animais , Lesões Encefálicas Traumáticas/imunologia , Terapia Combinada/métodos , Modelos Animais de Doenças , Imunidade , Inflamação/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Ratos Sprague-Dawley
3.
J Neuroinflammation ; 15(1): 84, 2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29548333

RESUMO

BACKGROUND: Traumatic brain injury (TBI) is a major cause of death and disability. TBI results in a prolonged secondary central neuro-inflammatory response. Previously, we have demonstrated that multiple doses (2 and 24 h after TBI) of multipotent adult progenitor cells (MAPC) delivered intravenously preserve the blood-brain barrier (BBB), improve spatial learning, and decrease activated microglia/macrophages in the dentate gyrus of the hippocampus. In order to determine if there is an optimum treatment window to preserve the BBB, improve cognitive behavior, and attenuate the activated microglia/macrophages, we administered MAPC at various clinically relevant intervals. METHODS: We administered two injections intravenously of MAPC treatment at hours 2 and 24 (2/24), 6 and 24 (6/24), 12 and 36 (12/36), or 36 and 72 (36/72) post cortical contusion injury (CCI) at a concentration of 10 million/kg. For BBB experiments, animals that received MAPC at 2/24, 6/24, and 12/36 were euthanized 72 h post injury. The 36/72 treated group was harvested at 96 h post injury. RESULTS: Administration of MAPC resulted in a significant decrease in BBB permeability when administered at 2/24 h after TBI only. For behavior experiments, animals were harvested post behavior paradigm. There was a significant improvement in spatial learning (120 days post injury) when compared to cortical contusion injury (CCI) in groups when MAPC was administered at or before 24 h. In addition, there was a significant decrease in activated microglia/macrophages in the dentate gyrus of hippocampus of the treated group (2/24) only when compared to CCI. CONCLUSIONS: Intravenous injections of MAPC at or before 24 h after CCI resulted in improvement of the BBB, improved cognitive behavior, and attenuated activated microglia/macrophages in the dentate gyrus.


Assuntos
Lesões Encefálicas Traumáticas/cirurgia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Células-Tronco Multipotentes/fisiologia , Animais , Barreira Hematoencefálica/fisiopatologia , Proteínas de Ligação ao Cálcio/metabolismo , Permeabilidade Capilar/fisiologia , Citocinas/metabolismo , Modelos Animais de Doenças , Proteínas do Domínio Duplacortina , Injeções Intraventriculares , Masculino , Aprendizagem em Labirinto , Proteínas dos Microfilamentos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Células-Tronco Multipotentes/transplante , Neuropeptídeos/metabolismo , Ratos , Tempo de Reação , Fatores de Tempo
4.
Stem Cells ; 35(5): 1259-1272, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28181347

RESUMO

Mesenchymal stromal cells (MSCs) are believed to mobilize from the bone marrow in response to inflammation and injury, yet the effects of egress into the vasculature on MSC function are largely unknown. Here we show that wall shear stress (WSS) typical of fluid frictional forces present on the vascular lumen stimulates antioxidant and anti-inflammatory mediators, as well as chemokines capable of immune cell recruitment. WSS specifically promotes signaling through NFκB-COX2-prostaglandin E2 (PGE2 ) to suppress tumor necrosis factor-α (TNF-α) production by activated immune cells. Ex vivo conditioning of MSCs by WSS improved therapeutic efficacy in a rat model of traumatic brain injury, as evidenced by decreased apoptotic and M1-type activated microglia in the hippocampus. These results demonstrate that force provides critical cues to MSCs residing at the vascular interface which influence immunomodulatory and paracrine activity, and suggest the potential therapeutic use of force for MSC functional enhancement. Stem Cells 2017;35:1259-1272.


Assuntos
Células da Medula Óssea/citologia , Células da Medula Óssea/imunologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/imunologia , Administração Intravenosa , Animais , Anti-Inflamatórios/metabolismo , Fenômenos Biomecânicos , Reatores Biológicos , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/terapia , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/biossíntese , Humanos , Imunomodulação , Inflamação/patologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Fenótipo , Ratos , Reologia , Transdução de Sinais , Estresse Mecânico
5.
Stem Cells ; 34(5): 1263-72, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26840479

RESUMO

Intravenous administration of bone marrow derived mesenchymal stem cells (MSCs) has been shown to reduce blood brain barrier compromise and improve neurocognition following traumatic brain injury (TBI). These effects occur in the absence of engraftment and differentiation of these cells in the injured brain. Recent studies have shown that soluble factors produced by MSCs mediate a number of the therapeutic effects. In this study, we sought to determine if intravenous administration of MSCs (IV-MSCs) could enhance hippocampal neurogenesis following TBI. Our results demonstrate that IV-MSC treatment attenuates loss of neural stem cells and promotes hippocampal neurogenesis in TBI injured mice. As Wnt signaling has been implicated in neurogenesis, we measured circulating Wnt3a levels in serum following IV-MSC administration and found a significant increase in Wnt3a. Concurrent with this increase, we detected increased activation of the Wnt/ß-catenin signaling pathway in hippocampal neurons. Furthermore, IV recombinant Wnt3a treatment provided neuroprotection, promoted neurogenesis, and improved neurocognitive function in TBI injured mice. Taken together, our results demonstrate a role for Wnt3a in the therapeutic potential of MSCs and identify Wnt3a as a potential stand-alone therapy or as part of a combination therapeutic strategy for the treatment of TBI. Stem Cells 2016;34:1263-1272.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Cognição , Células-Tronco Mesenquimais/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Recuperação de Função Fisiológica , Proteína Wnt3A/metabolismo , Proteína Wnt3A/uso terapêutico , Administração Intravenosa , Animais , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/fisiopatologia , Sobrevivência Celular/efeitos dos fármacos , Cognição/efeitos dos fármacos , Hipocampo/patologia , Hipocampo/fisiopatologia , Humanos , Pulmão/metabolismo , Transplante de Células-Tronco Mesenquimais , Camundongos Endogâmicos C57BL , Modelos Biológicos , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Neurogênese/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Resultado do Tratamento , Via de Sinalização Wnt/efeitos dos fármacos , Proteína Wnt3A/sangue , Proteína Wnt3A/farmacologia
6.
Stem Cells ; 33(12): 3530-44, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26299440

RESUMO

Mesenchymal stem cells (MSCs) have been shown to have potent therapeutic effects in a number of disorders including traumatic brain injury (TBI). However, the molecular mechanism(s) underlying these protective effects are largely unknown. Herein we demonstrate that tissue inhibitor of matrix metalloproteinase-3 (TIMP3), a soluble protein released by MSCs, is neuroprotective and enhances neuronal survival and neurite outgrowth in vitro. In vivo in a murine model of TBI, intravenous recombinant TIMP3 enhances dendritic outgrowth and abrogates loss of hippocampal neural stem cells and mature neurons. Mechanistically we demonstrate in vitro and in vivo that TIMP3-mediated neuroprotection is critically dependent on activation of the Akt-mTORC1 pathway. In support of the neuroprotective effect of TIMP3, we find that intravenous delivery of recombinant TIMP3 attenuates deficits in hippocampal-dependent neurocognition. Taken together, our data strongly suggest that TIMP3 has direct neuroprotective effects that can mitigate the deleterious effects associated with TBI, an area with few if any therapeutic options.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Transtornos Cognitivos/tratamento farmacológico , Hipocampo/metabolismo , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Inibidor Tecidual de Metaloproteinase-3/farmacologia , Animais , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/patologia , Hipocampo/patologia , Camundongos , Células-Tronco Neurais/patologia , Neurônios/patologia
7.
Sci Rep ; 13(1): 16142, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752232

RESUMO

Traumatic brain injury (TBI) results in activated microglia. Activated microglia can be measured in vivo by using positron emission topography (PET) ligand peripheral benzodiazepine receptor standardized uptake values (PBR28suv). Cell based therapies have utilized autologous bone marrow mononuclear cells (BMMNCs) to attenuate activated microglia after TBI. This study aims to utilize in vivo PBR28suv to assess the efficacy of BMMNCs therapy after TBI. Seventy-two hours after CCI injury, BMMNCs were harvested from the tibia and injected via tail-vein at 74 h after injury at a concentration of 2 million cells per kilogram of body weight. There were three groups of rats: Sham, CCI-alone and CCI-BMMNCs (AUTO). One hundred twenty days after injury, rodents were imaged with PBR28 and their cognitive behavior assessed utilizing the Morris Water Maze. Subsequent ex vivo analysis included brain volume and immunohistochemistry. BMMNCs therapy attenuated PBR28suv in comparison to CCI alone and it improved spatial learning as measured by the Morris Water Maze. Ex vivo analysis demonstrated preservation of brain volume, a decrease in amoeboid-shaped microglia in the dentate gyrus and an increase in the ratio of ramified to amoeboid microglia in the thalamus. PBR28suv is a viable option to measure efficacy of BMMNCs therapy after TBI.


Assuntos
Lesões Encefálicas Traumáticas , Microglia , Animais , Ratos , Medula Óssea , Elétrons , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/terapia , Tomografia por Emissão de Pósitrons
8.
J Neuroinflammation ; 9: 228, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-23020860

RESUMO

INTRODUCTION: We have demonstrated previously that the intravenous delivery of multipotent adult progenitor cells (MAPC) after traumatic brain injury affords neuroprotection via interaction with splenocytes, leading to an increase in systemic anti-inflammatory cytokines. We hypothesize that the observed modulation of the systemic inflammatory milieu is related to T regulatory cells and a subsequent increase in the locoregional neuroprotective M2 macrophage population. METHODS: C57B6 mice were injected with intravenous MAPC 2 and 24 hours after controlled cortical impact injury. Animals were euthanized 24, 48, 72, and 120 hours after injury. In vivo, the proportion of CD4(+)/CD25(+)/FOXP3(+) T-regulatory cells were measured in the splenocyte population and plasma. In addition, the brain CD86(+) M1 and CD206(+) M2 macrophage populations were quantified. A series of in vitro co-cultures were completed to investigate the need for direct MAPC:splenocyte contact as well as the effect of MAPC therapy on M1 and M2 macrophage subtype apoptosis and proliferation. RESULTS: Significant increases in the splenocyte and plasma T regulatory cell populations were observed with MAPC therapy at 24 and 48 hours, respectively. In addition, MAPC therapy was associated with an increase in the brain M2/M1 macrophage ratio at 24, 48 and 120 hours after cortical injury. In vitro cultures of activated microglia with supernatant derived from MAPC:splenocyte co-cultures also demonstrated an increase in the M2/M1 ratio. The observed changes were secondary to an increase in M1 macrophage apoptosis. CONCLUSIONS: The data show that the intravenous delivery of MAPC after cortical injury results in increases in T regulatory cells in splenocytes and plasma with a concordant increase in the locoregional M2/M1 macrophage ratio. Direct contact between the MAPC and splenocytes is required to modulate activated microglia, adding further evidence to the central role of the spleen in MAPC-mediated neuroprotection.


Assuntos
Células-Tronco Adultas/transplante , Lesões Encefálicas/patologia , Lesões Encefálicas/terapia , Microglia/fisiologia , Células-Tronco Multipotentes/fisiologia , Administração Intravenosa , Células-Tronco Adultas/fisiologia , Análise de Variância , Animais , Antígenos CD/metabolismo , Barreira Hematoencefálica/fisiopatologia , Comunicação Celular/fisiologia , Proliferação de Células , Terapia Baseada em Transplante de Células e Tecidos , Células Cultivadas , Técnicas de Cocultura , Modelos Animais de Doenças , Citometria de Fluxo , Fatores de Transcrição Forkhead/metabolismo , Humanos , Fígado/citologia , Linfócitos/metabolismo , Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Multipotentes/transplante
9.
Pediatr Res ; 71(6): 668-74, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22476046

RESUMO

INTRODUCTION: Infants with gastroschisis (GS) have significant morbidity from dysmotility, feeding intolerance, and are at increased risk of developing intestinal failure. Although the molecular mechanisms regulating GS-related intestinal dysfunction (GRID) are largely unknown, we hypothesized that mechanical constriction (nonocclusive mesenteric hypertension (NMH)) from the abdominal wall defect acts as a stimulus for GRID. The purpose of this study was to determine the effect of NMH on intestinal function and inflammation. METHODS: Neonatal rats had placement of a silastic disk to the base of the mesentery (NMH) or no disk placement (Sham). At 24 and 72 h, mesenteric venous pressures (MVPs), intestinal transit, electric impedance, permeability, length, and tissue water content were measured. RESULTS: After placement of the silastic disk, there was a significant increase in MVP at both time points. There was also decreased intestinal transit. As compared to Sham animals, NMH animals had significant changes in bowel impedance without an increase in tissue water, suggesting significant intestinal remodeling. NMH rats had significantly increased smooth-muscle thickness and loss of intestinal length as compared with Sham rats. DISCUSSION: NMH may be an initiating factor for GRID. Measurement of MVP and/or bowel impedance may be a way to assess severity and monitor progression and/or resolution of GRID.


Assuntos
Gastrosquise/complicações , Hipertensão/complicações , Enteropatias/etiologia , Mesentério/fisiopatologia , Animais , Pressão Sanguínea/fisiologia , Motilidade Gastrointestinal/fisiologia , Gastrosquise/fisiopatologia , Hipertensão/fisiopatologia , Enteropatias/fisiopatologia , Masculino , Modelos Animais , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional/fisiologia , Índice de Gravidade de Doença
10.
PLoS One ; 16(5): e0251601, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34038436

RESUMO

Traumatic brain injury (TBI) causes both physical disruption of the blood brain barrier (BBB) and altered immune responses that can lead to significant secondary brain injury and chronic inflammation within the central nervous system (CNS). Cell therapies, including mesenchymal stromal cells (MSC), have been shown to restore BBB integrity and augment endogenous splenic regulatory T cells (Treg), a subset of CD4+ T cells that function to regulate immune responses and prevent autoimmunity. We have recently shown that infusion of human cord blood-derived Treg decreased neuroinflammation after TBI in vivo and in vitro. However, while both cells have demonstrated anti-inflammatory and regenerative potential, they likely utilize differing, although potentially overlapping, mechanisms. Furthermore, studies investigating these two cell types together, as a combination therapy, are lacking. In this study, we compared the ability of Treg+MSC combination therapy, as well as MSC and Treg monotherapies, to improve BBB permeability in vivo and suppress inflammation in vitro. While Treg+MSC combination did not significantly augment potency in vivo, our in vitro data demonstrates that combination therapy may augment therapeutic potency and immunosuppressive potential compared to Treg or MSC monotherapy.


Assuntos
Barreira Hematoencefálica/imunologia , Lesões Encefálicas Traumáticas , Tolerância Imunológica , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/imunologia , Linfócitos T Reguladores , Animais , Lesões Encefálicas Traumáticas/imunologia , Lesões Encefálicas Traumáticas/terapia , Modelos Animais de Doenças , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/transplante
11.
Crit Care Med ; 38(3): 861-70, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20168148

RESUMO

OBJECTIVE: To investigate the molecular mechanisms leading to edema-induced decreases in intestinal smooth muscle myosin light-chain phosphorylation. Intestinal interstitial edema often develops during abdominal surgery and after fluid resuscitation in trauma patients. Intestinal edema causes decreased intestinal contractile activity via decreased intestinal smooth muscle myosin light-chain phosphorylation, leading to slower intestinal transit. Interstitial edema development is a complex phenomenon, resulting in many changes to the interstitial environment surrounding intestinal smooth muscle cells. Thus, the mechanism(s) by which intestinal edema development causes intestinal dysfunction are likely to be multifactorial. DESIGN: Randomized animal study. SETTING: University laboratory. SUBJECTS: Male Sprague-Dawley rats, weighing 250-350 g. INTERVENTION: Studies were performed in a rat model in which a combination of mesenteric venous hypertension and administration of resuscitative fluids induces intestinal edema, mimicking the clinical setting of damage control resuscitation. MEASUREMENTS AND MAIN RESULTS: Microarray analysis of edematous intestinal smooth muscle combined with an in silico search for overrepresented transcription factor binding sites revealed the involvement of nuclear factor-kappaB in edema-induced intestinal dysfunction. Nuclear factor-kappaB deoxyribonucleic acid binding activity was significantly increased in edematous intestinal smooth muscle compared with controls. Inhibition of nuclear factor-kappaB activation blocked edema-induced decreases in basal intestinal contractile activity. Inhibition of nuclear factor-kappaB activation also attenuated edema-induced decreases in myosin light-chain phosphorylation. CONCLUSIONS: We conclude that intestinal edema activates nuclear factor-kappaB, which, in turn, triggers a gene regulation program that eventually leads to decreased myosin light-chain phosphorylation and, thus, decreased intestinal contractile activity.


Assuntos
Edema/fisiopatologia , Motilidade Gastrointestinal/fisiologia , Enteropatias/fisiopatologia , Fosfatase de Miosina-de-Cadeia-Leve/fisiologia , NF-kappa B/fisiologia , Transdução de Sinais/fisiologia , Animais , Hidratação , Regulação da Expressão Gênica/fisiologia , Masculino , Músculo Liso/fisiopatologia , Fosfatase de Miosina-de-Cadeia-Leve/genética , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação/genética , Fosforilação/fisiologia , Ratos , Ratos Sprague-Dawley , Ressuscitação , Transdução de Sinais/genética , Pressão Venosa/fisiologia
12.
J Surg Res ; 163(1): 102-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20605598

RESUMO

BACKGROUND: Administration of L-nil, a selective inhibitor of inducible nitric oxide synthase (iNOS), improves ileus in an animal model of resuscitation induced intestinal edema. The purpose of this study was to elucidate the iNOS/nitric oxide (NO) signal transduction pathway in intestinal edema. MATERIALS AND METHODS: Male Sprague Dawley rats were divided into two groups; CONTROL and RESUS+VH (edema, 80 cc/kg normal saline (resuscitation) with mesenteric venous hypertension). iNOS mRNA and protein, iNOS activity, NO tissue levels, soluble guanylyl cyclase (sGC) expression, and cyclic guanosine monophosphate (cGMP) levels were measured. As a functional endpoint, we evaluated intestinal contractile strength and frequency in L-nil treated animals. RESULTS: Edema was associated with increased iNOS mRNA and protein expression without subsequent increases in iNOS activity or tissue NO levels. There was no significant change in sGC expression or increase in cGMP induced by edema. Administration of L-nil did not decrease edema development or preserve contractile strength, but increased contractile frequency. CONCLUSION: Hydrostatic intestinal edema is not associated with increased iNOS activity or tissue NO levels. Administration of L-nil in edema increases intestinal contractile frequency. This may represent a potential mechanism for the amelioration of ileus seen with the administration of L-nil.


Assuntos
GMP Cíclico/metabolismo , Edema/metabolismo , Motilidade Gastrointestinal , Enteropatias/enzimologia , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Animais , Guanilato Ciclase/metabolismo , Pressão Hidrostática , Imuno-Histoquímica , Lisina/análogos & derivados , Masculino , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
13.
J Trauma ; 68(3): 682-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20220423

RESUMO

BACKGROUND: : Current abdominal compartment syndrome (ACS) models rely on intraperitoneal instillation of fluid, air, and other space-occupying substances. Although this allows for the study of the effects of increased abdominal pressure, it poorly mimics its pathogenesis. We have developed the first reported large animal model of ACS incorporating hemorrhagic shock/resuscitation. METHODS: : Hemorrhagic shock was induced and maintained (1 hour) in 12 Yorkshire swine by bleeding to a mean arterial pressure (MAP) of 50 mm Hg. The collected blood plus two additional volumes of crystalloid was then reinfused. Mesenteric venous hypertension was induced by tightening a previously placed portal vein snare in a nonocclusive manner to mimic the effects of abdominal packing. Crystalloids were infused to maintain MAP. Hemodynamic measurements, abdominal pressure, peak inspiratory pressures, urine output, and blood chemistries were measured sequentially. Animals were studied for 36 hours after decompression. RESULTS: : ACS (intra-abdominal pressure of > or =20 mm Hg with new organ dysfunction) developed in all animals. There were significant increases in peak inspiratory pressure, central venous pressure, and pulmonary artery pressure and decreases in MAP upon development of ACS. Urine output was significantly decreased before decompression. Mean blood lactate decreased and base excess increased significantly after decompression. CONCLUSIONS: : We have created the first reported physiologic animal ACS model incorporating hemorrhagic shock/resuscitation and the effects of damage control surgery.


Assuntos
Cavidade Abdominal , Síndromes Compartimentais/etiologia , Síndromes Compartimentais/fisiopatologia , Modelos Animais de Doenças , Choque Hemorrágico/etiologia , Choque Hemorrágico/fisiopatologia , Animais , Pressão Sanguínea , Síndromes Compartimentais/terapia , Descompressão Cirúrgica , Feminino , Hidratação , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/fisiopatologia , Insuficiência de Múltiplos Órgãos/terapia , Reprodutibilidade dos Testes , Choque Hemorrágico/terapia , Suínos
14.
Tissue Eng Part A ; 26(11-12): 591-601, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31739755

RESUMO

Secondary alveolar bone grafts (ABGs) are the standard treatment for the alveolar defect in patients with cleft lip and palate (CLP), but remain invasive and have several disadvantages such as delayed timing of alveolar repair, donor-site complications, graft resorption, and need for multiple surgeries. Earlier management of the alveolar defect (primary ABG) would be ideal, but is limited by the minimal bony donor sites available in the infant. In this study we used a critical-size alveolar bone defect model in the rat to investigate the use of Wharton's Jelly (WJ), the stem cell-rich connective tissue matrix of the umbilical cord, to generate bone within the alveolar cleft. Human WJ was isolated and implanted into a critical-size alveolar bone defect model representative of secondary cleft ABG surgery in 10-11-week-old male Sprague-Dawley rats. The defects were monitored with CT imaging of living animals to evaluate bone regrowth and healing over 24 weeks, followed by histomorphometric evaluation at 24 weeks, after the last CT scan. CT data confirmed that the defect size was critical and did not lead to the union of the bones in the control animals (n = 12) for the entire duration of the study. New bone growth was stimulated leading to partial-to-full closure of the defect in the animals treated with WJ (n = 12). Twenty four weeks postoperatively, the percent increase in new bone formation in the WJ-treated group (156.58% ± 20.67%) was markedly higher than that in the control group (50.36% ± 21.07%) (p < 0.05). Histomorphometric data also revealed significantly greater new bone formation in WJ-treated versus control animals, confirming CT findings. qPCR analysis of human Alu elements was unable to detect any appreciable long-term persistence of human cells in the new bone, indicating that WJ may enhance bone growth by mediating osteoinduction in the host tissue, rather than through osteogenic differentiation of WJ-embedded cells. Impact statement In this study, Wharton's Jelly enhanced bone growth in a preclinical alveolar defect model, indicating its potential use as a natural adjunct in the repair of the alveolar cleft defect in patients with cleft lip and palate (CLP). The clinical success of this approach would represent a paradigm shift in the treatment of patients with CLP by reducing or eliminating the need for subsequent secondary alveolar bone graft and reducing their number of lifetime surgeries.


Assuntos
Fissura Palatina/cirurgia , Geleia de Wharton , Animais , Regeneração Óssea/fisiologia , Diferenciação Celular/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Humanos , Osteogênese/fisiologia , Ratos , Ratos Sprague-Dawley , Microtomografia por Raio-X
15.
Sci Rep ; 10(1): 10729, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32612177

RESUMO

The immune system plays critical roles in promoting tissue repair during recovery from neurotrauma but is also responsible for unchecked inflammation that causes neuronal cell death, systemic stress, and lethal immunodepression. Understanding the immune response to neurotrauma is an urgent priority, yet current models of traumatic brain injury (TBI) inadequately recapitulate the human immune response. Here, we report the first description of a humanized model of TBI and show that TBI places significant stress on the bone marrow. Hematopoietic cells of the marrow are regionally decimated, with evidence pointing to exacerbation of underlying graft-versus-host disease (GVHD) linked to presence of human T cells in the marrow. Despite complexities of the humanized mouse, marrow aplasia caused by TBI could be alleviated by cell therapy with human bone marrow mesenchymal stromal cells (MSCs). We conclude that MSCs could be used to ameliorate syndromes triggered by hypercytokinemia in settings of secondary inflammatory stimulus that upset marrow homeostasis such as TBI. More broadly, this study highlights the importance of understanding how underlying immune disorders including immunodepression, autoimmunity, and GVHD might be intensified by injury.


Assuntos
Lesões Encefálicas Traumáticas/fisiopatologia , Doença Enxerto-Hospedeiro/etiologia , Tolerância Imunológica/imunologia , Células-Tronco Mesenquimais/citologia , Linfócitos T/imunologia , Animais , Feminino , Doença Enxerto-Hospedeiro/patologia , Doença Enxerto-Hospedeiro/terapia , Masculino , Transplante de Células-Tronco Mesenquimais , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID
16.
Crit Care Med ; 37(11): 2946-52, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19770732

RESUMO

OBJECTIVE: To characterize membrane conductivity by applying mathematical modeling techniques and immunohistochemistry and to localize and predict areas of the bowel where aquaporins may be associated with edema resolution/prevention associated with hypertonic saline. Intestinal edema induced by resuscitation and mesenteric venous hypertension impairs intestinal transit/contractility. Hypertonic saline decreases intestinal edema and improves transit. Aquaporins are water transport membrane proteins that may be up-regulated with edema and/or hypertonic saline. DESIGN: Laboratory study. SETTING: University research laboratory. SUBJECTS: Male Sprague Dawley rats, weighing 270 to 330 g. INTERVENTIONS: Rats were randomized to control (with and without hypertonic saline) and mesenteric venous hypertension with either 80 mL/kg normal saline (RESUS + VH + VEH) or 80 mL/kg normal saline with hypertonic saline (RESUS + VH + HTS). After 6 hrs, intestinal wet/dry ratios, urine output, peritoneal fluid, and intraluminal fluid were measured. Hydraulic conductivity was calculated from our previously known and published pressure-flow data. The cDNA microarray, Western blot, polymerase chain reaction, and immunohistochemistry studies were conducted for candidate aquaporins and distribution in intestinal edema resolution. MEASUREMENTS AND MAIN RESULTS: Hypertonic saline decreased edema and increased urine, intraluminal, and peritoneal fluid volume. RESUS + VH favors fluid flux into the interstitium. Hypertonic saline causes increased hydraulic conductivity at the seromuscular and mucosal surfaces at the same time limiting flow into the interstitium. This is associated with increased aquaporin 4 expression in the intestinal mucosa and submucosa. CONCLUSIONS: Hypertonic saline mitigates intestinal edema development and promotes fluid redistribution secondary to increased membrane conductivity at the mucosal and seromuscular surfaces. This is associated with up-regulation of aquaporin 4 gene expression and protein. Aquaporin 4 may be a useful therapeutic target for strategies to enhance edema resolution.


Assuntos
Aquaporina 4/metabolismo , Edema/metabolismo , Enteropatias/metabolismo , Mucosa Intestinal/metabolismo , Solução Salina Hipertônica/farmacocinética , Animais , Líquido Ascítico , Transporte Biológico , Edema/etiologia , Edema/prevenção & controle , Imuno-Histoquímica , Enteropatias/etiologia , Enteropatias/prevenção & controle , Masculino , Modelos Biológicos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Ressuscitação/efeitos adversos , Regulação para Cima , Urina
17.
J Surg Res ; 152(2): 264-70, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18541267

RESUMO

BACKGROUND: Mesenteric ischemia/reperfusion (I/R) is a common problem in critically ill patients and is frequently associated with myocardial dysfunction. Several potential mechanisms have been proposed to be involved in the myocardial dysfunction associated with mesenteric I/R, including nuclear factor kappa B (NF kappaB)-mediated tumor necrosis factor alpha (TNF-alpha) release leading to cardiodepression. Thus, we sought to investigate the effect of NF kappaB inhibition on mesenteric I/R-associated myocardial dysfunction in a large animal model (dog). MATERIALS AND METHODS: A total of 21 mongrel dogs were anesthetized and mechanically ventilated. Animals were instrumented with a Swan-Ganz Catheter, left ventricle (LV) pressure manometer, and ultrasonic crystals. Mesenteric I/R consisted of 60 min of ischemia followed by 180 min of reperfusion. Seven animals received pyrrolidine dithiocarbamate (PDTC, 100 mg/kg) prior to mesenteric I/R (I/R PDTC). Another group of animals (n = 7) without mesenteric ischemia received PDTC following baseline measurements and served as control for the effect of PDTC alone (PDTC). Preload recruitable stroke work, +/-dp/dt(max), isovolumic relaxation (tau), and cardiac output were measured. Myocardial tissue was analyzed for NF kappaB activity, TNF-alpha production, and myocardial apoptosis. RESULTS: Mesenteric I/R impaired both LV systolic and diastolic function. Administration of PDTC worsened LV function impairment following I/R. In addition, PDTC resulted in decreased LV function even without mesenteric I/R. NF kappaB, TNF-alpha, and myocardial apoptosis were not different among the groups. CONCLUSIONS: Mesenteric I/R affects LV function independent of NF kappaB and TNF-alpha pathways. PDTC acts as a cardiac depressant through a thus far unknown mechanism. Therefore, evaluation of cardiac and hemodynamic function in experimental setups using PDTC has to be carefully interpreted.


Assuntos
Coração/fisiopatologia , NF-kappa B/fisiologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Pressão Sanguínea , Débito Cardíaco , Morte Celular , Modelos Animais de Doenças , Cães , Feminino , Artéria Femoral/fisiologia , Ventrículos do Coração/fisiopatologia , Hemodinâmica , Humanos , Veias Jugulares/fisiologia , Masculino , Artérias Mesentéricas/patologia , Artérias Mesentéricas/fisiologia , Artérias Mesentéricas/fisiopatologia , Reperfusão , Respiração Artificial , Volume Sistólico/fisiologia , Sístole
18.
J Surg Res ; 155(2): 283-92, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19482297

RESUMO

OBJECTIVE: Edema formation, inflammation, and ileus in the intestine are commonly seen in conditions like gastroschisis, inflammatory bowel disease, and cirrhosis. We hypothesized that early enteral feeding would improve intestinal transit. We also wanted to study the impact of early enteral feeding on global gene expression in the intestine. DESIGN: Rats were divided into Sham or Edema +/- immediate enteral nutrition (IEN). At 12 h, small intestinal transit via FITC-Dextran and tissue water were measured. Ileum was harvested for total RNA to analyze gene expression using cDNA microarray with validation using real-time PCR. Data are expressed as mean +/- SEM, n = 4-6 and (*), (**) = P < 0.05 versus all groups using ANOVA. RESULTS: IEN markedly improved intestinal transit with minimal genetic alterations in Edema animals. Major alterations in gene expression were detected in primary, cellular and macromolecular metabolic activities. Edema also altered more genes involved with the regulation of the actin cytoskeleton. CONCLUSIONS: Intestinal edema results in impaired small intestinal transit and globally increased gene expression. Early enteral nutrition improves edema-induced impaired transit and minimizes gene transcriptional activity.


Assuntos
Edema/fisiopatologia , Edema/terapia , Nutrição Enteral , Motilidade Gastrointestinal/fisiologia , Regulação da Expressão Gênica/fisiologia , Enteropatias/fisiopatologia , Enteropatias/terapia , Actinas/metabolismo , Animais , Apoptose/fisiologia , Citoesqueleto/metabolismo , Dextranos , Modelos Animais de Doenças , Edema/genética , Fluoresceína-5-Isotiocianato/análogos & derivados , Perfilação da Expressão Gênica , Enteropatias/genética , Mucosa Intestinal/metabolismo , Intestinos/patologia , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia
19.
Shock ; 29(5): 598-602, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18414233

RESUMO

Crystalloid-based resuscitation of severely injured trauma patients leads to intestinal edema. A potential mechanism of intestinal edema-induced ileus is a reduction of myosin light chain phosphorylation in intestinal smooth muscle. We sought to determine if the onset of edema initiated a measurable, early mechanotransductive signal and if hypertonic saline (HS) can modulate this early signal by changing intestinal fluid balance. An anesthetized rat model of acute interstitial intestinal edema was used. At laparotomy, the mesenteric lymphatic was cannulated to measure lymph flow and pressure, and a fluid-filled micropipette was placed in the intestinal submucosa to measure interstitial pressure. Rats were randomized into four groups (n=6 per group): sham, mesenteric venous hypertension+80 mL/kg 0.9% isotonic sodium chloride solution (ISCS 80), mesenteric venous hypertension+80 mL/kg 0.9% ISCS+4 mL/kg 7.5% saline (ISCS 80+HS), or 4 mL/kg 7.5% saline (HS alone) to receive the aforementioned intravenous fluid administered over 5 min. Measurements were made 30 min after completion of the preparation. Tissue water, lymph flow, and interstitial pressure were measured. Resultant applied volume induced stress on the smooth muscle (sigmaravi-muscularis) was calculated. Mesenteric venous hypertension and crystalloid resuscitation caused intestinal edema that was prevented by HS. Intestinal edema caused an early increase in intestinal interstitial pressure that was prevented by HS. Hypertonic saline did not augment lymphatic removal of intestinal edema. sigmaravi-muscularis was increased with onset of edema and prevented by HS, paralleling the interstitial pressure data. Intestinal edema causes an early increase in interstitial pressure that is prevented by HS. Prevention of the edema-induced increase in interstitial pressure serves to blunt the mechanotransductive signal of sigmaravi-muscularis.


Assuntos
Mucosa Intestinal/metabolismo , Sais/farmacologia , Animais , Edema/patologia , Hipertensão , Masculino , Modelos Biológicos , Modelos Teóricos , Músculo Liso/patologia , Miócitos de Músculo Liso/metabolismo , Ratos , Ratos Sprague-Dawley , Ressuscitação , Cloreto de Sódio/farmacologia , Equilíbrio Hidroeletrolítico
20.
Stem Cells Transl Med ; 5(1): 33-44, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26586775

RESUMO

UNLABELLED: More than 6.5 million patients are burdened by the physical, cognitive, and psychosocial deficits associated with traumatic brain injury (TBI) in the U.S. Despite extensive efforts to develop neuroprotective therapies for this devastating disorder, there have been no successful outcomes in human clinical trials to date. Retrospective studies have shown that ß-adrenergic receptor blockers, specifically propranolol, significantly decrease mortality of TBI through mechanisms not yet fully elucidated but are thought to counterbalance a hyperadrenergic state resulting from a TBI. Conversely, cellular therapies have been shown to improve long-term behavior following TBI, likely by reducing inflammation. Given the nonredundancy in their therapeutic mechanisms, we hypothesized that a combination of acute propranolol followed by mesenchymal stem cells (MSCs) isolated from human bone marrow would have additive effects in treating a rodent model of TBI. We have found that the treatments are well-tolerated individually and in combination with no adverse events. MSCs decrease BBB permeability at 96 hours after injury, inhibit a significant accumulation of activated microglia/macrophage in the thalamic region of the brain both short and long term, and enhance neurogenesis short term. Propranolol decreases edema and reduces the number of fully activated microglia at 7 days and the number of semiactivated microglia at 120 days. Combinatory treatment improved cognitive and memory functions 120 days following TBI. Therefore, the results here suggest a new, efficacious sequential treatment for TBI may be achieved using the ß-blocker propranolol followed by MSC treatment. SIGNIFICANCE: Despite continuous efforts, traumatic brain injury (TBI) remains the leading cause of death and disability worldwide in patients under the age of 44. In this study, an animal model of moderate-severe TBI was treated with an acute dose of propranolol followed by a delayed dose of human mesenchymal stem cells (MSCs), resulting in improved short- and long-term measurements. These results have direct translational application. They reinforce the inevitable clinical trial of MSCs to treat TBI by demonstrating, among other benefits, a notable decrease in chronic neuroinflammation. More importantly, these results demonstrate that MSCs and propranolol, which is increasingly being used clinically for TBI, are compatible treatments that improve overall outcome.


Assuntos
Lesões Encefálicas/terapia , Células-Tronco Mesenquimais/metabolismo , Microglia/metabolismo , Neurogênese/efeitos dos fármacos , Propranolol/farmacologia , Adulto , Aloenxertos , Animais , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/patologia , Microglia/patologia , Ratos , Ratos Sprague-Dawley
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