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1.
Nature ; 544(7651): 488-492, 2017 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-28424512

RESUMO

Ageing drives changes in neuronal and cognitive function, the decline of which is a major feature of many neurological disorders. The hippocampus, a brain region subserving roles of spatial and episodic memory and learning, is sensitive to the detrimental effects of ageing at morphological and molecular levels. With advancing age, synapses in various hippocampal subfields exhibit impaired long-term potentiation, an electrophysiological correlate of learning and memory. At the molecular level, immediate early genes are among the synaptic plasticity genes that are both induced by long-term potentiation and downregulated in the aged brain. In addition to revitalizing other aged tissues, exposure to factors in young blood counteracts age-related changes in these central nervous system parameters, although the identities of specific cognition-promoting factors or whether such activity exists in human plasma remains unknown. We hypothesized that plasma of an early developmental stage, namely umbilical cord plasma, provides a reservoir of such plasticity-promoting proteins. Here we show that human cord plasma treatment revitalizes the hippocampus and improves cognitive function in aged mice. Tissue inhibitor of metalloproteinases 2 (TIMP2), a blood-borne factor enriched in human cord plasma, young mouse plasma, and young mouse hippocampi, appears in the brain after systemic administration and increases synaptic plasticity and hippocampal-dependent cognition in aged mice. Depletion experiments in aged mice revealed TIMP2 to be necessary for the cognitive benefits conferred by cord plasma. We find that systemic pools of TIMP2 are necessary for spatial memory in young mice, while treatment of brain slices with TIMP2 antibody prevents long-term potentiation, arguing for previously unknown roles for TIMP2 in normal hippocampal function. Our findings reveal that human cord plasma contains plasticity-enhancing proteins of high translational value for targeting ageing- or disease-associated hippocampal dysfunction.


Assuntos
Envelhecimento/metabolismo , Proteínas Sanguíneas/farmacologia , Sangue Fetal/química , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Plasticidade Neuronal/efeitos dos fármacos , Envelhecimento/efeitos dos fármacos , Animais , Proteínas Sanguíneas/administração & dosagem , Proteínas Sanguíneas/metabolismo , Cognição/efeitos dos fármacos , Cognição/fisiologia , Feminino , Hipocampo/citologia , Humanos , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Camundongos , Plasticidade Neuronal/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Análise Serial de Proteínas , Memória Espacial/efeitos dos fármacos , Memória Espacial/fisiologia , Inibidor Tecidual de Metaloproteinase-2/administração & dosagem , Inibidor Tecidual de Metaloproteinase-2/antagonistas & inibidores , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Inibidor Tecidual de Metaloproteinase-2/farmacologia
2.
PLoS One ; 8(6): e65083, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23762288

RESUMO

A decrease in fertility can have a negative economic impact, both locally and over a broader geographical scope, and this is especially the case with regard to the cattle industry. Therefore, much interest exists in evaluating proteins that might be able to increase the fertility of sperm. Heparin binding proteins (HBPs), specifically the fertility associated antigen (FAA) and the Type-2 tissue inhibitor of metalloproteinase (TIMP-2), act to favor the capacitation and acrosome reaction and perhaps even modulate the immune system's response toward the sperm. The objective of this research was to determine the effect on fertility of adding recombinant FAA (rFAA) and recombinant TIMP-2 (rTIMP-2) to bovine semen before cryopreservation for use in an artificial insemination (AI) program in a tropical environment. For this experiment, 100 crossbred (Bos taurus x Bos indicus) heifers were selected based on their estrus cycle, body condition score (BCS), of 4 to 6 on a scale of 1 to 9, and adequate anatomical conformation evaluated by pelvic and genital (normal) measurements. Heifers were synchronized using estradiol benzoate (EB), Celosil® (PGF2α) (Shering-Plough) and a controlled internal drug release (CIDR) device was inserted that contained progesterone. Inseminations were performed in two groups at random, 50 animals per group. The control group was inseminated with conventional semen. The treatment group was inseminated with semen containing rFAA (25 µg/mL) and rTIMP-2 (25 µg/mL). In the control group a 16% pregnancy rate was obtained versus a 40% pregnancy rate for the HBP treatment group, resulting in a significant difference (P = 0.0037). Given the results herein, one may conclude that the HBPs can increase fertility and could be an option for cattle in tropical conditions; however, one needs to consider the environment, nutrition, and the genetic interaction affecting the final result in whatever reproductive program that is implemented.


Assuntos
Fertilidade/fisiologia , Inseminação Artificial , Proteínas de Membrana/metabolismo , Taxa de Gravidez , Proteínas Recombinantes/metabolismo , Espermatozoides/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Animais , Bovinos , Criopreservação , Sincronização do Estro , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Masculino , Proteínas de Membrana/administração & dosagem , Ovulação , Gravidez , Proteínas Recombinantes/administração & dosagem , Sêmen/metabolismo , Inibidor Tecidual de Metaloproteinase-2/administração & dosagem
3.
Zhonghua Gan Zang Bing Za Zhi ; 17(11): 835-8, 2009 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19958643

RESUMO

OBJECTIVE: To investigate the molecular mechanism of the inhibitory effect of curcumine on the migration and invasion of hepatic stellate cells (HSC). METHODS: Rat hepatic stellate cells were cultured and activated with ConA. Matrix metalloproteinase-2 (MMP-2) expression and activity was determined by Western blot and gelatin zymography. Migration and invasion of HSC was assessed by wound healing assay and modified Boyden chamber assay. RESULTS: Curcumine reduced the level and activity of MMP-2 expression in activated HSC in a dose-dependent manner. When treated with 25, 50 or 100 micromol/L curcumine, the expression of MMP-2 was reduced by 21.8%+/-5.1%, 65.5%+/-9.2% or 87.9%+/-11.5% (P < 0.05), and the activity of MMP-2 was also significantly reduced by curcumine. Migration and invasion of activated HSC was also inhibited by curcumine in a dose-dependent way. When treated with 25, 50 or 100 micromol/L curcumine, the migration of activated HSC was reduced by 27.5%+/-5.8%, 54.4%+/-7.6% or 67.1%+/-9.3% (P < 0.05), and the invasion of activated HSC was also significantly reduced by curcumine. CONCLUSION: Curcumine inhibits migration and invasion of activated HSC by reducing MMP-2 expression and activity.


Assuntos
Movimento Celular/efeitos dos fármacos , Curcumina/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática/prevenção & controle , Metaloproteinase 2 da Matriz/metabolismo , Inibidor Tecidual de Metaloproteinase-2/farmacologia , Animais , Western Blotting , Células Cultivadas , Concanavalina A/administração & dosagem , Concanavalina A/farmacologia , Curcumina/administração & dosagem , Relação Dose-Resposta a Droga , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/metabolismo , Ratos , Inibidor Tecidual de Metaloproteinase-2/administração & dosagem
4.
Am J Physiol Cell Physiol ; 291(4): C740-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16707552

RESUMO

There is substantial evidence linking blood-brain barrier (BBB) failure during cerebral ischemia to matrix metalloproteinases (MMP). BBB function may be affected by loss of shear stress under normoxia/normoglycemia, as during cardiopulmonary bypass procedures. The present study used an in vitro flow-perfused BBB model to analyze the individual contributions of flow, cytokine levels, and circulating blood leukocytes on the release/activity of MMP-9, MMP-2, and their endogenous inhibitors, the tissue inhibitors of MMPs (TIMPs), TIMP-1, and TIMP-2. The presence of circulating blood leukocytes under normoxic/normoglycemic flow cessation/reperfusion significantly increased the luminal levels of MMP-9 and activity of MMP-2, accompanied by partial reduction of TIMP-1, complete reduction of TIMP-2 and increased BBB permeability. These changes were not observed during constant flow with circulating blood leukocytes, or after normoxic/normoglycemic or hypoxic/hypoglycemic flow cessation/reperfusion without circulating blood leukocytes. The addition of anti-IL-6 or anti-TNF-alpha antibody in the lumen before reperfusion suppressed the levels of MMP-9 and activity of MMP-2, had no effect on TIMP-1, and completely restored TIMP-2 and BBB integrity. Injection of TIMP-2 in the lumen before reperfusion prevented the activation of MMP-2 and BBB permeability. These data indicate that blood leukocytes and loss of flow are major factors in the activation of MMP-2, and that cytokine-mediated differential regulation of TIMP-1 and TIMP-2 may contribute significantly to BBB failure.


Assuntos
Fenômenos Fisiológicos Sanguíneos , Barreira Hematoencefálica/metabolismo , Mediadores da Inflamação/fisiologia , Leucócitos/fisiologia , Metaloproteinases da Matriz/metabolismo , Inibidores Teciduais de Metaloproteinases/metabolismo , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Permeabilidade Capilar/efeitos dos fármacos , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Injeções , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Ratos , Ratos Sprague-Dawley , Estresse Mecânico , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/administração & dosagem , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Inibidor Tecidual de Metaloproteinase-2/farmacologia
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