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1.
J Neurosci ; 39(21): 4179-4192, 2019 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-30886019

RESUMO

Obesity and insulin resistance elicit blood-brain barrier (BBB) breakdown in humans and animal models, but the relative contributions of the two pathologies remain poorly understood. These studies initially addressed the temporal progression of cerebrovascular dysfunction relative to dietary obesity or diet-induced insulin resistance in male mice. Obesity increased BBB permeability to the low molecular weight fluorophore sodium fluorescein (NaFl), whereas diet-induced insulin resistance increased permeability to both NaFl and Evans blue, which forms a high molecular weight complex with serum albumin. Serial section transmission electron microscopy analysis of hippocampal capillaries revealed that diabetes promotes involution of tight junctions, fenestration of endothelial cells, and pericyte regression. Chronic activation of adenosine receptor 2a (Adora2a) erodes tight junctions between endothelial cells of the cerebral vasculature in other models of chronic neuropathology, and we observed that acute Adora2a antagonism normalized BBB permeability in wild-type mice with diet-induced insulin resistance. Experiments in mice with inducible deletion of Adora2a in endothelial cells revealed protection against BBB breakdown with diet-induced insulin resistance, despite comparable metabolic dysfunction relative to nontransgenic littermates. Protection against BBB breakdown was associated with decreased vascular inflammation, recovery of hippocampal synaptic plasticity, and restoration of hippocampus-dependent memory. These findings indicate that Adora2a-mediated signaling in vascular endothelial cells disrupts the BBB in dietary obesity, and implicate cerebrovascular dysfunction as the underlying mechanism for deficits in synaptic plasticity and cognition with obesity and insulin resistance.SIGNIFICANCE STATEMENT The blood-brain barrier (BBB) restricts the entry of circulating factors into the brain, but obesity promotes BBB breakdown in humans and animal models. We used transgenic mice with resistance to BBB breakdown to investigate the role of neurovascular dysfunction in high-fat diet (HFD)-induced cognitive impairment. Transgenic mice with inducible ablation of Adora2a in endothelial cells were protected against BBB breakdown on HFD, despite comparable metabolic impairments relative to normal mice. Transgenic mice were also resistant to HFD-induced cognitive dysfunction and were protected against deficits in hippocampal synaptic plasticity. These findings indicate that Adora2a-mediated signaling in endothelial cells mediates obesity-induced BBB breakdown, and implicate cerebrovascular dysfunction as the mechanism for deficits in synaptic plasticity and cognition with obesity and diabetes.


Assuntos
Permeabilidade Capilar/fisiologia , Disfunção Cognitiva/metabolismo , Resistência à Insulina/fisiologia , Receptor A2A de Adenosina/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Disfunção Cognitiva/patologia , Dieta Hiperlipídica/efeitos adversos , Células Endoteliais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Obesidade/metabolismo
2.
Int J Mol Sci ; 19(2)2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29443941

RESUMO

Anaplastic thyroid carcinoma (ATC) is almost universally fatal. Elevated keratin-8 (KRT8) protein expression is an established diagnostic cancer biomarker in several epithelial cancers (but not ATC). Several keratins, including KRT8, have been suggested to have a role in cell biology beyond that of structural cytoskeletal proteins. Here, we provide evidence that KRT8 plays a direct role in the growth of ATCs. Genomic and transcriptomic analysis of >5000 patients demonstrates that KRT8 mutation and copy number amplification are frequently evident in epithelial-derived cancers. Carcinomas arising from diverse tissues exhibit KRT8 mRNA and protein overexpression when compared to normal tissue levels. Similarly, in a panel of patient-derived ATC cell lines and patient tumors, KRT8 expression shows a similar pattern. sh-RNA-mediated KRT8 knockdown in these cell lines increases apoptosis, whereas forced overexpression of KRT8 confers resistance to apoptosis under peroxide-induced cell stress conditions. We further show that KRT8 protein binds to annexin A2, a protein known to mediate apoptosis as well as the redox pathway.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma/metabolismo , Queratina-8/genética , Neoplasias da Glândula Tireoide/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Anexina A2/metabolismo , Apoptose , Biomarcadores Tumorais/metabolismo , Carcinoma/genética , Carcinoma/patologia , Linhagem Celular Tumoral , Feminino , Dosagem de Genes , Humanos , Queratina-8/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Ligação Proteica , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Regulação para Cima
3.
Cytokine ; 64(1): 310-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23769592

RESUMO

Approximately 5-10% of subjects with prediabetes become diabetic every year. Inflammation is involved in the development of obesity-related type 2 diabetes (T2D). However, to date, the relationship between inflammation and prediabetes, defined by hemoglobin A1c (HbA1c) ≥5.7 and <6.5%, remains largely unexplored, especially in African Americans. Therefore, in this study we examined a comprehensive panel of 13 cytokines involved in the inflammatory response in overweight/obese subjects with prediabetes. A total of 21 otherwise healthy, overweight/obese, young adult African American females with prediabetes, together with 20 matched overweight/obese controls, were selected for this study. Plasma cytokines were assessed by multiplex cytokine profiling. Plasma concentrations of interleukin (IL)-5, IL-6, IL-7, tumor necrosis factor-α (TNF-α), and granulocyte-monocyte colony-stimulating factor (GM-CSF) were significantly higher in the prediabetic group, as compared to the control group (all p<0.05). Plasma concentrations of all the other cytokines, interferon-γ (IFN-γ), IL-1ß, IL-2, IL-4, IL-8, IL-10, IL-12p70 and IL-13, seemed to be elevated in the prediabetic group, but failed to reach statistical significances. Upon merging both groups, HbA1c was found to be positively correlated with IFN-γ, IL-1ß, IL-2, IL-5, IL-7, IL-8, TNF-α and GM-CSF. This study demonstrates elevated levels of various pro-inflammatory cytokines in overweight/obese young subjects with prediabetes, which place them at higher risk of developing T2D and cardiovascular diseases. Our data also call for further investigations in animal models and population cohorts to establish the roles of a variety of pro-inflammatory cytokines in the early development of obesity-related T2D.


Assuntos
Citocinas/sangue , Diabetes Mellitus Tipo 2/metabolismo , Hemoglobinas Glicadas/metabolismo , Obesidade/metabolismo , Estado Pré-Diabético/metabolismo , Adolescente , Adulto , Negro ou Afro-Americano , Tamanho Corporal , Citocinas/metabolismo , Feminino , Humanos , Inflamação/metabolismo , Pessoa de Meia-Idade , Adulto Jovem
4.
Pediatr Res ; 74(2): 206-10, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23863785

RESUMO

BACKGROUND: Metabolic abnormalities in obesity can overstimulate the renal epithelial sodium channel (ENaC) and subsequently lead to blood pressure (BP) elevation. Prostasin, a membrane-bound/secretive serine protease, is thought to activate ENaC via the proteolytic cleavage of the channel. Our specific aim was to explore whether there is a relationship between adiposity and urinary prostasin excretion at the population level. METHODS: In 271 African-American adolescents, urinary prostasin concentrations were determined by enzyme-linked immunosorbent assay and normalized by urinary creatinine. RESULTS: Urinary prostasin excretion increased in the overweight/obese group (n = 110, 38.2 ± 4.0 ng/mg) vs. the normal-weight group (n = 161, 20.7 ± 1.2 ng/mg, P = 0.03). Urinary prostasin excretion was significantly correlated with BMI percentiles (r = 0.14, P = 0.02), waist circumference (r = 0.13, P = 0.05), total body fat mass (r = 0.20, P < 0.01), and percentage body fat (r = 0.23, P < 0.01). Urinary prostasin excretion was also correlated with plasma aldosterone (r = 0.11, P = 0.05) and systolic BP (SBP; r = 0.15, P = 0.02), but the significances disappeared after adjustment of any of the adiposity variables. CONCLUSION: Our data for the first time suggest that adiposity plays a role in urinary prostasin excretion, and its associations with aldosterone and BP appear to be modulated by adiposity. Whether urinary prostasin excretion is a biomarker/mechanism underlying obesity-related hypertension deserves further investigations.


Assuntos
Adiposidade/fisiologia , Negro ou Afro-Americano , Sobrepeso/urina , Serina Endopeptidases/urina , Adolescente , Creatinina/urina , Ensaio de Imunoadsorção Enzimática , Humanos , Sobrepeso/metabolismo , Serina Endopeptidases/metabolismo
5.
Nat Genet ; 36(8): 837-41, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15247916

RESUMO

Previous studies have suggested more than 20 genetic intervals that are associated with susceptibility to type 1 diabetes (T1D), but identification of specific genes has been challenging and largely limited to known candidate genes. Here, we report evidence for an association between T1D and multiple single-nucleotide polymorphisms in 197 kb of genomic DNA in the IDDM5 interval. We cloned a new gene (SUMO4), encoding small ubiquitin-like modifier 4 protein, in the interval. A substitution (M55V) at an evolutionarily conserved residue of the crucial CUE domain of SUMO4 was strongly associated with T1D (P = 1.9 x 10(-7)). SUMO4 conjugates to I kappa B alpha and negatively regulates NF kappa B transcriptional activity. The M55V substitution resulted in 5.5 times greater NF kappa B transcriptional activity and approximately 2 times greater expression of IL12B, an NF kappa B-dependent gene. These findings suggest a new pathway that may be implicated in the pathogenesis of T1D.


Assuntos
Diabetes Mellitus Tipo 1/genética , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/genética , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/fisiologia , Sequência de Aminoácidos , Estudos de Casos e Controles , Regulação da Expressão Gênica , Predisposição Genética para Doença , Humanos , Dados de Sequência Molecular , Mapeamento Físico do Cromossomo , Polimorfismo de Nucleotídeo Único , Homologia de Sequência de Aminoácidos
6.
Biomedicines ; 11(3)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36979801

RESUMO

Stroke is one of the most common diseases that leads to brain injury and mortality in patients, and intracerebral hemorrhage (ICH) is the most devastating subtype of stroke. Though the prevalence of ICH increases with aging, the effect of aging on the pathophysiology of ICH remains largely understudied. Moreover, there is no effective treatment for ICH. Recent studies have demonstrated the potential of circulating microRNAs as non-invasive diagnostic and prognostic biomarkers in various pathological conditions. While many studies have identified microRNAs that play roles in the pathophysiology of brain injury, few demonstrated their functions and roles after ICH. Given this significant knowledge gap, the present study aims to identify microRNAs that could serve as potential biomarkers of ICH in the elderly. To this end, sham or ICH was induced in aged C57BL/6 mice (18-24 months), and 24 h post-ICH, serum microRNAs were isolated, and expressions were analyzed. We identified 28 significantly dysregulated microRNAs between ICH and sham groups, suggesting their potential to serve as blood biomarkers of acute ICH. Among those microRNAs, based on the current literature, miR-124-3p, miR-137-5p, miR-138-5p, miR-219a-2-3p, miR-135a-5p, miR-541-5p, and miR-770-3p may serve as the most promising blood biomarker candidates of ICH, warranting further investigation.

7.
Diabetes ; 72(2): 245-260, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36367881

RESUMO

Preferential energy storage in subcutaneous adipose tissue (SAT) confers protection against obesity-induced pathophysiology in females. Females also exhibit distinct immunological responses, relative to males. These differences are often attributed to sex hormones, but reciprocal interactions between metabolism, immunity, and gonadal steroids remain poorly understood. We systematically characterized adipose tissue hypertrophy, sex steroids, and inflammation in male and female mice after increasing durations of high-fat diet (HFD)-induced obesity. After observing that sex differences in adipose tissue distribution before HFD were correlated with lasting protection against inflammation in females, we hypothesized that a priori differences in the ratio of subcutaneous to visceral fat might mediate this relationship. To test this, male and female mice underwent SAT lipectomy (LPX) or sham surgery before HFD challenge, followed by analysis of glial reactivity, adipose tissue inflammation, and reproductive steroids. Because LPX eliminated female resistance to the proinflammatory effects of HFD without changing circulating sex hormones, we conclude that sexually dimorphic organization of subcutaneous and visceral fat determines susceptibility to inflammation in obesity.


Assuntos
Doenças Neuroinflamatórias , Caracteres Sexuais , Feminino , Masculino , Camundongos , Animais , Distribuição Tecidual , Obesidade/metabolismo , Inflamação , Hormônios Esteroides Gonadais
8.
Nat Commun ; 12(1): 4623, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34330904

RESUMO

Visceral obesity increases risk of cognitive decline in humans, but subcutaneous adiposity does not. Here, we report that beige adipocytes are indispensable for the neuroprotective and anti-inflammatory effects of subcutaneous fat. Mice lacking functional beige fat exhibit accelerated cognitive dysfunction and microglial activation with dietary obesity. Subcutaneous fat transplantation also protects against chronic obesity in wildtype mice via beige fat-dependent mechanisms. Beige adipocytes restore hippocampal synaptic plasticity following transplantation, and these effects require the anti-inflammatory cytokine interleukin-4 (IL4). After observing beige fat-mediated induction of IL4 in meningeal T-cells, we investigated the contributions of peripheral lymphocytes in donor fat. There was no sign of donor-derived lymphocyte trafficking between fat and brain, but recipient-derived lymphocytes were required for the effects of transplantation on cognition and microglial morphology. These findings indicate that beige adipocytes oppose obesity-induced cognitive impairment, with a potential role for IL4 in the relationship between beige fat and brain function.


Assuntos
Adipócitos Bege/metabolismo , Tecido Adiposo Bege/metabolismo , Adiposidade , Obesidade/metabolismo , Gordura Subcutânea/metabolismo , Adipócitos Bege/citologia , Animais , Anti-Inflamatórios/metabolismo , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Humanos , Interleucina-4/metabolismo , Camundongos Obesos , Plasticidade Neuronal/fisiologia , Fármacos Neuroprotetores/metabolismo , Obesidade/etiologia , Obesidade/fisiopatologia , Gordura Subcutânea/transplante , Linfócitos T/metabolismo
9.
Am J Physiol Regul Integr Comp Physiol ; 299(2): R590-5, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20504903

RESUMO

The aim of this study is to elucidate the effects of interleukin-6 (IL-6) on the expression and activity of the epithelial sodium channel (ENaC), which is one of the key mechanisms underlying tubular sodium reabsorption. M-1 cortical collecting duct cells were treated with IL-6 (100 ng/ml) for 12 h. Real-time polymerase chain reaction and immunoblotting were employed to examine the mRNA and protein abundance. Transepithelial voltage (V(te)) and resistance (R(te)) were measured with an ohm/voltmeter (EVOM, WPI). The equivalent current was calculated as the ratio of V(te) to R(te.) Treatment with IL-6 (n = 5) increased the mRNA abundance of alpha-ENaC by 11 +/- 7% (P = not significant), beta-ENaC by 78 +/- 14% (P = 0.01), gamma-ENaC by 185 +/- 38% (P = 0.02), and prostasin by 29 +/- 5% (P = 0.01), all normalized by beta-actin. Treatment with IL-6 increased the protein expression of alpha-ENaC by 19 +/- 3% (P = 0.001), beta-ENaC by 89 +/- 21% (P = 0.01), gamma-ENaC by 36 +/- 12% (P = 0.02), and prostasin by 33 +/- 6% (P = 0.02). The amiloride-sensitive sodium current increased by 37 +/- 5%, from 6.0 +/- 0.4 to 8.2 +/- 0.3 muA/cm(2) (P < 0.01), in the cells treated with IL-6 compared with controls (P = 0.01). Aprotinin (28 microg/ml), a prostasin inhibitor, reduced the amiloride-sensitive sodium current by 61 +/- 5%, from 6.1 +/- 0.3 to 3.7 +/- 0.2 muA/cm(2) (P = 0.01). The magnitude of the IL-6-induced amiloride-sensitive sodium current in the presence of aprotinin dropped by 57 +/- 2%, from 8.6 +/- 0.2 to 4.9 +/- 0.2 muA/cm(2) (P < 0.01). This study has identified a novel function of IL-6, namely, IL-6 may activate ENaC. Therefore, renal inflammation mediated by IL-6 likely contributes to impaired pressure natriuresis.


Assuntos
Canais Epiteliais de Sódio/metabolismo , Interleucina-6/metabolismo , Córtex Renal/metabolismo , Túbulos Renais Coletores/metabolismo , Amilorida/farmacologia , Animais , Aprotinina/farmacologia , Western Blotting , Linhagem Celular , Impedância Elétrica , Bloqueadores do Canal de Sódio Epitelial , Canais Epiteliais de Sódio/genética , Regulação da Expressão Gênica , Córtex Renal/efeitos dos fármacos , Túbulos Renais Coletores/efeitos dos fármacos , Potenciais da Membrana , Camundongos , Camundongos Transgênicos , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina Endopeptidases/metabolismo , Bloqueadores dos Canais de Sódio/farmacologia
10.
J Clin Invest ; 130(4): 1961-1976, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31935195

RESUMO

Induction of the inflammasome protein cryopyrin (NLRP3) in visceral adipose tissue (VAT) promotes release of the proinflammatory cytokine IL-1ß in obesity. Although this mechanism contributes to peripheral metabolic dysfunction, effects on the brain remain unexplored. We investigated whether visceral adipose NLRP3 impairs cognition by activating microglial IL-1 receptor 1 (IL-1R1). After observing protection against obesity-induced neuroinflammation and cognitive impairment in NLRP3-KO mice, we transplanted VAT from obese WT or NLRP3-KO donors into lean recipient mice. Transplantation of VAT from a WT donor (TRANSWT) increased hippocampal IL-1ß and impaired cognition, but VAT transplants from comparably obese NLRP3-KO donors (TRANSKO) had no effect. Visceral adipose NLRP3 was required for deficits in long-term potentiation (LTP) in transplant recipients, and LTP impairment in TRANSWT mice was IL-1 dependent. Flow cytometric and gene expression analyses revealed that VAT transplantation recapitulated the effects of obesity on microglial activation and IL-1ß gene expression, and visualization of hippocampal microglia revealed similar effects in vivo. Inducible ablation of IL-1R1 in CX3CR1-expressing cells eliminated cognitive impairment in mice with dietary obesity and in transplant recipients and restored immunoquiescence in hippocampal microglia. These results indicate that visceral adipose NLRP3 impairs memory via IL-1-mediated microglial activation and suggest that NLRP3/IL-1ß signaling may underlie correlations between visceral adiposity and cognitive impairment in humans.


Assuntos
Receptor 1 de Quimiocina CX3C/metabolismo , Cognição , Hipocampo/metabolismo , Gordura Intra-Abdominal/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Obesidade/metabolismo , Receptores Tipo I de Interleucina-1/metabolismo , Animais , Receptor 1 de Quimiocina CX3C/genética , Hipocampo/patologia , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Gordura Intra-Abdominal/patologia , Gordura Intra-Abdominal/transplante , Camundongos , Camundongos Knockout , Microglia/metabolismo , Microglia/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Obesidade/genética , Obesidade/patologia , Receptores Tipo I de Interleucina-1/genética , Transdução de Sinais/genética
11.
Pediatr Res ; 65(4): 443-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19127211

RESUMO

Prostasin is a membrane-bound/secretive serine protease interacting with aldosterone and the epithelial sodium channel in the kidney. We and others have previously proposed the concept of stress-induced pressure natriuresis (SIPN) where increased urinary sodium excretion (UNaV) is coupled with elevated blood pressure (BP) in response to behavioral stress in normotensive adolescents. This study thus aimed to test the relationship between prostasin and pressure natriuresis using the SIPN model. A cohort of 102 normotensive black adolescents (mean age: 17.0 +/- 1.2 y; 56% females) were placed on a controlled sodium (4000 +/- 200 mg/d) and potassium (2600 +/- 200 mg/d) diet for three days before testing. The SIPN protocol consisted of a 1-h baseline period, a 1-h stress period (competitive video game), and a 1-h recovery period. During the stress period, BP elevation was coupled with an increase in UNaV. Urinary prostasin concentration had more than a 2-fold reduction from baseline (38.4 +/- 32.7 ng/mL) to stress (17.2 +/- 16.0 ng/mL), and further declined during recovery (12.1 +/- 16.2 ng/mL) (p < 0.001). Urinary prostasin was inversely correlated with UNaV during stress (r = -0.43, p = 0.0001), even after being normalized by urinary creatinine. Our data suggest that urinary prostasin could be a novel biomarker and/or mechanism for renal pressure natriuresis in normotensive black adolescents.


Assuntos
Negro ou Afro-Americano , Natriurese , Serina Endopeptidases/urina , Estresse Psicológico/urina , Adolescente , Aldosterona/sangue , Biomarcadores/urina , Pressão Sanguínea , Creatinina/sangue , Creatinina/urina , Feminino , Humanos , Masculino , Potássio/sangue , Sódio/sangue , Estresse Psicológico/fisiopatologia , Fatores de Tempo
12.
Am J Hypertens ; 21(9): 1028-33, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18583984

RESUMO

BACKGROUND: Prostasin, a serine protease, is suggested to be a novel mechanism regulating the epithelial sodium channel (ENaC) expressed in the distal nephron. This study aimed to evaluate whether the human prostasin gene is a novel candidate gene underlying blood pressure (BP) elevation. METHODS: In a sample of healthy African-American (AA) and European-American (EA) twin subjects aged 17.6 +/- 3.3 years (n = 920, 45% AAs), race-specific tagging single-nucleotide polymorphisms (tSNPs) were identified to tag all the available SNPs +/- 2 kb up- and downstream of the prostasin gene from HapMap at r2 of 0.8-1.0. Selection yielded four tSNPs in AAs and one in EAs, with one tSNP (rs12597511: C to T) present in both AAs and EAs. RESULTS: For rs12597511, CT and TT genotypes exhibited higher systolic BP (SBP) than CC genotype (115.9 +/- 1.1 mm Hg vs. 113.7 +/- 0.6 mm Hg, P = 0.025 (AAs); and 110.7 +/- 0.5 mm Hg vs. 109.6 +/- 0.6 mm Hg, P = 0.115 (EAs)). CT and TT genotypes compared with CC genotype showed a significant increase in diastolic BP (DBP) in both racial groups (62.5 +/- 0.7 mm Hg vs. 60.4 +/- 0.4 mm Hg, P = 0.003 (AAs); and 58.2 +/- 0.3 mm Hg vs. 56.7 +/- 0.4 mm Hg, P = 0.007 (EAs)). Furthermore, there was an increase in radial pulse wave velocity (PWV) in subjects with CT and TT genotype as compared with those with CC genotype (6.5 +/- 0.1 vs. 6.1 +/- 0.1 m/s, P < 0.0001) (EAs); and 6.7 +/- 0.1 vs. 6.6 +/- 0.1 m/s, P = 0.354 (AAs)). Analyses combining AAs and EAs consistently demonstrated a statistical significance of rs12597511 on all the phenotypes including SBP/DBP and PWV. CONCLUSION: Genetic variation of the prostasin gene may be implicated in the development of hypertension in youths..


Assuntos
Hipertensão/genética , Serina Endopeptidases/genética , Adolescente , Alelos , Feminino , Variação Genética , Genótipo , Humanos , Masculino , Grupos Raciais
13.
Laryngoscope ; 127(8): E258-E264, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28480504

RESUMO

OBJECTIVES/HYPOTHESIS: The most promising stem cell-derived tracheal transplantation approach is dependent upon the use of decellularized tracheal grafts. It has been assumed that a sterilization step, such as gamma radiation, would damage the delicate extracellular matrix of the graft, thus rendering it less viable for cellular repopulation, although this has not been thoroughly investigated. STUDY DESIGN: Laboratory-based comparative analysis. METHODS: Fifteen murine tracheas of strain C57/B-6 mice were obtained. Thirteen were subjected to a detergent-enzymatic decellularization process. Of these decellularized tracheas (DT), eight were irradiated, exposing five tracheas to a radiation level of 25 kGy (DT25) and three to 5 kGy (DT5). Two were left untreated. The two untreated tracheas, two DTs, and two DT25s were prepared and examined using both scanning and transmission electron microscopy. Bioburden calculations were obtained from three DTs, three DT25s, and three DT5s by homogenization, serial dilution, and streak plating. RESULTS: Electron microscopy of untreated fresh tracheas and DTs showed a slight qualitative degradation of cartilage ultrastructure due to the decellularization process. In contrast, examination of DT25 shows significant degradation including poor overall preservation of cartilage architecture with disorganized collagen fibers. The nonirradiated DTs had a calculated bacterial bioburden of 7.8 × 107 to 3.4 × 108 colony-forming units per gram. Both the DT25 and DT5 specimens were found to have a bioburden of zero. CONCLUSIONS: Gamma radiation at 25 kGy degrades the architecture of decellularized tracheal grafts. These ultrastructural changes may prove detrimental to graft viability; however, bioburden calculations suggest that a 5 kGy radiation dose may be sufficient for sterilization. LEVEL OF EVIDENCE: NA Laryngoscope, 127:E258-E264, 2017.


Assuntos
Raios gama , Esterilização/métodos , Traqueia/efeitos da radiação , Traqueia/transplante , Animais , Estudos de Viabilidade , Camundongos , Doses de Radiação , Traqueia/microbiologia , Traqueia/ultraestrutura
14.
PLoS One ; 12(12): e0188424, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29216203

RESUMO

BACKGROUND: Clinical trials are scant and equivocal on whether vitamin D can ameliorate arterial stiffness, particularly in populations at high risk for vitamin D deficiency and cardiovascular disease (CVD). This study determined the dose-response effects of vitamin D3 supplementation on arterial stiffness in overweight African Americans with vitamin D deficiency. METHODS: Seventy overweight African Americans (aged 13-45 years) with serum 25-hydroxyvitamin D [25(OH)D] levels ≤ 20 ng/mL were randomized to monthly oral supplementation of 18,000 IU (~600 IU/day, n = 17), 60,000 IU (~2000 IU/day, n = 18), or 120,000 IU (~4000 IU/day, n = 18) of vitamin D3 or placebo (n = 17) for 16-weeks. The arterial stiffness measurements, carotid-femoral pulse wave velocity (PWV) and carotid-radial PWV, were assessed by applanation tonometry at baseline and 16 weeks. RESULTS: Vitamin D3 supplementation demonstrated a dose-response increase in serum 25(OH)D concentrations between groups (P<0.01). A significant downward linear trend was observed for carotid-femoral PWV (P<0.01), as the mean changes in carotid-femoral PWV across the four treatment groups were 0.13 m/s (95% CI: -0.24, 0.51 m/s) for placebo, 0.02 m/s (95% CI: -0.34, 0.38 m/s) for 600 IU/day group, -0.11 m/s (95% CI: -0.50, 0.27 m/s) for the 2,000 IU/day group, and -0.70 m/s (95% CI: -1.07, -0.32 m/s) for the 4,000 IU/day group. Findings were similar for carotid-radial PWV (P = 0.03), as the mean changes in carotid-radial PWV across the four treatment groups were 0.24 m/s (95% CI: -0.45, 0.92 m/s) for placebo, 0.09 m/s (95% CI: -0.54, 0.73 m/s) for 600 IU/day group, -0.57 m/s (95% CI: -1.20, 0.07 m/s) for the 2,000 IU/day group, and -0.61 m/s (95% CI: -1.25, 0.02 m/s) for the 4,000 IU/day group. CONCLUSION: Arterial stiffness was improved by vitamin D3 supplementation in a dose-response manner in overweight African Americans with vitamin D deficiency.


Assuntos
Artérias/fisiopatologia , Negro ou Afro-Americano , Colecalciferol/administração & dosagem , Obesidade/complicações , Rigidez Vascular/efeitos dos fármacos , Deficiência de Vitamina D/tratamento farmacológico , Adolescente , Adulto , Colecalciferol/farmacologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Placebos , Deficiência de Vitamina D/complicações , Adulto Jovem
15.
Naunyn Schmiedebergs Arch Pharmacol ; 373(6): 415-27, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16955284

RESUMO

The aims of this study were to determine effects of diabetes duration on myocardial ischemia/reperfusion (I/R) injury and test whether time-dependent differences in sensitivity of the streptozotocin diabetic rat heart to I/R are related to differences in vascular density, levels of vascular endothelial growth factor (VEGF) or endothelial nitric oxide synthase (eNOS) expression, NO formation, activation of Akt, and/or oxidative stress. After 2 or 6 weeks of streptozotocin-induced diabetes, I/R injury was induced by occlusion (30 min) and reperfusion of the left descending coronary artery. After 2 weeks of diabetes, infarct size and cleavage of caspase-3, a proapoptosis signal, were decreased as compared with normoglycemic controls or rats that had been diabetic for 6 weeks, whereas capillary density and levels of VEGF and eNOS protein and cardiac NO(x) levels were all increased. Phosphorylation of Akt, a prosurvival signal, was also significantly increased after 2 weeks of diabetes. Cardiac lipid peroxidation was comparable to controls after 2 weeks of diabetes, whereas levels of nitrotyrosine, a peroxynitrite biomarker, were reduced. After 6 weeks of diabetes, lipid peroxidation was increased and levels of VEGF and plasma NO were reduced as compared with controls or rats diabetic for 2 weeks. Our results indicate endogenous cardioprotective mechanisms become transiently activated in this early stage of diabetes and that this may protect the heart from I/R injury through enhancement of VEGF and eNOS expression, NO formation, activation of cell survival signals, and decreased oxidative stress.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Transdução de Sinais/fisiologia , Fator A de Crescimento do Endotélio Vascular/biossíntese , Animais , Pressão Sanguínea/fisiologia , Western Blotting , Capilares/fisiologia , Caspase 3/metabolismo , Sobrevivência Celular/fisiologia , Circulação Coronária/fisiologia , Frequência Cardíaca/fisiologia , Peroxidação de Lipídeos/fisiologia , Masculino , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Neovascularização Fisiológica/fisiologia , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase Tipo III/biossíntese , Proteína Oncogênica v-akt/metabolismo , Estresse Oxidativo/fisiologia , Fosforilação , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional/fisiologia , Tirosina/análogos & derivados , Tirosina/metabolismo
16.
J Mol Med (Berl) ; 83(7): 504-13, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15806321

RESUMO

Post-translational modification of proteins by phosphorylation, methylation, acetylation, or ubiquitylation represent central mechanisms through which various biological processes are regulated. Reversible covalent modification (i.e., sumoylation) of proteins by the small ubiquitin-like modifier (SUMO) has also emerged as an important mechanism contributing to the dynamic regulation of protein function. Sumoylation has been linked to the pathogenesis of a variety of disorders including Alzheimer's disease (AD), Huntington's disease (HD), and type 1 diabetes (T1D). Advances in our understanding of the role of sumoylation suggested a novel regulatory mechanism for the regulation of immune responsive gene expression. In this review, we first update recent advances in the field of sumoylation, then specifically evaluate its regulatory role in several key signaling pathways for immune response and discuss its possible implication in T1D pathogenesis.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Proteína SUMO-1/metabolismo , Sequência de Aminoácidos , Animais , Humanos , Dados de Sequência Molecular , Proteína SUMO-1/química , Transdução de Sinais , Transcrição Gênica
17.
Laryngoscope ; 126(5): E179-83, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26599262

RESUMO

OBJECTIVES/HYPOTHESIS: Clinically, inflammatory polyps are found in the middle turbinate (MT) in patients with chronic rhinosinusitis (CRS) but not in the inferior turbinate (IT). The purpose of this study was to investigate differences in protein expression between IT and MT tissue in patients with CRS. STUDY DESIGN: Prospective cohort. METHODS: Pathologic specimens obtained from patients with CRS undergoing functional endoscopic sinus surgery with IT reduction were evaluated by immunohistochemical analysis of inflammatory markers cysteinyl leukotriene 1 receptor (CysLT1R), toll-like receptor 2 (TLR2), and vascular cell adhesion molecule 1 (VCAM1). Protein expression was quantified with nuance multispectral analysis and results compared between MT and IT tissue. RESULTS: The total expression of VCAM1 and CysLT1R was decreased in the IT compared to the MT. There was no difference in total TLR2 expression between the IT and MT. When comparing patients with eosinophilic CRS to noneosinophilic CRS (neCRS), there was decreased expression of VCAM1 in the IT of patients with neCRS. When comparing patients with nasal polyposis to those without polyps, there was decreased expression of VCAM1 in the IT of patients without polyps. CONCLUSIONS: There is a difference in protein receptor expression of VCAM1 and CysLT1R in MT compared to IT tissue. Although the leukotrienes are a well-known target for treatment of chronic sinusitis, this is the first study demonstrating an upregulation of VCAM1 expression in the MT and could be a potential future target for the treatment of CRS. LEVEL OF EVIDENCE: NA Laryngoscope, 126:E179-E183, 2016.


Assuntos
Eosinofilia/metabolismo , Pólipos Nasais/metabolismo , Rinite/metabolismo , Sinusite/metabolismo , Conchas Nasais/metabolismo , Adulto , Doença Crônica , Eosinofilia/complicações , Eosinofilia/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Pólipos Nasais/complicações , Pólipos Nasais/patologia , Estudos Prospectivos , Receptores de Leucotrienos/análise , Rinite/etiologia , Rinite/patologia , Sinusite/etiologia , Sinusite/patologia , Receptor 2 Toll-Like/análise , Conchas Nasais/patologia , Molécula 1 de Adesão de Célula Vascular/análise
18.
Mol Pain ; 1: 15, 2005 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-15840172

RESUMO

Divalent metal ions such as copper, manganese, and cobalt are essential for cell development, differentiation, function and survival. These essential metal ions are delivered into intracellular domains as cofactors for enzymes involved in neuropeptide and neurotransmitter synthesis, superoxide metabolism, and other biological functions in a target specific fashion. Altering the homeostasis of these essential metal ions is known to connect to a number of human diseases including Alzheimer disease, amyotrophic lateral sclerosis, and pain. It remains unclear how these essential metal ions are delivered to intracellular targets in mammalian cells. Here we report that rat spinal cord dorsal horn neurons express ACDP4, a member of Ancient Conserved Domain Protein family. By screening a pretransformed human fetal brain cDNA library in a yeast two-hybrid system, we have identified that ACDP4 specifically interacts with COX11, an intracellular metal ion chaperone. Ectopic expression of ACDP4 in HEK293 cells resulted in enhanced toxicity to metal ions including copper, manganese, and cobalt. The metal ion toxicity became more pronounced when ACDP4 and COX11 were co-expressed ectopically in HEK293 cells, suggesting a functional coupling between them. Our results indicate a role of ACDP4 in metal ion homeostasis and toxicity. This is the first report revealing a functional aspect of this ancient conserved domain protein family. We propose that ACDP is a family of transporter protein or chaperone proteins for delivering essential metal ions in different mammalian tissues. The expression of ACDP4 on spinal cord dorsal horn neurons may have implications in sensory neuron functions under physiological and pathological conditions.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/fisiologia , Homeostase/fisiologia , Transporte de Íons/fisiologia , Metais/metabolismo , Chaperonas Moleculares/fisiologia , Animais , Proteínas de Transporte de Cátions , Linhagem Celular , Sequência Conservada , Proteínas de Transporte de Cobre , Citoplasma/fisiologia , Complexo de Proteínas da Cadeia de Transporte de Elétrons , Humanos , Proteínas Mitocondriais , Células do Corno Posterior/metabolismo , Estrutura Terciária de Proteína , Ratos , Ratos Sprague-Dawley
19.
BMC Obes ; 2: 27, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26217542

RESUMO

BACKGROUND: A critical need exists to better understand the physiological sequel of vitamin D supplementation in obese individuals and African Americans. The aim was to comprehensively evaluate dose- and time-responses of a panel of vitamin D biomarkers to vitamin D supplements in this population. METHODS: We conducted a 16-week randomized, double-blinded, and placebo-controlled clinical trial. Seventy overweight/obese African Americans (age 13-45 years, 84 % females) with 25-hydroxyvitamin D [25(OH)D] concentrations ≤20 ng/mL were randomly assigned to receive a supervised monthly oral vitamin D3 of 18,000 IU (~600 IU/day, n = 17), 60,000 IU (~2000 IU/day, n = 18), 120,000 IU (~4000 IU/day, n = 18), or placebo (n = 17). RESULTS: There were significant dose- and time-responses of circulating 25(OH)D, 1,25-dihydroxyvitamin D [1,25(OH)2D], and intact parathyroid hormone (iPTH), but not fibroblast growth factor-23 (FGF-23), phosphorus and urine calcium to the vitamin D supplements. The mean 25(OH)D concentrations in the 2000 IU and 4000 IU groups reached ≥30 ng/mL as early as 8-weeks and remained at similar level at 16-weeks. The increase of 25(OH)D was significantly higher in the 4000 IU group than all the other groups at 8-weeks. The increase of 1,25(OH)2D was significantly higher in the 2000 IU and 4000 IU groups than the placebo at 8-weeks. Only the 4000 IU compared to the placebo significantly reduced iPTH at 8- and 16-weeks. CONCLUSIONS: Our RCT, for the first time, comprehensively evaluated time- and dose- responses of vitamin D supplementation in overweight/obese African Americans with suboptimal vitamin D status. Circulating 25(OH)D, 1,25(OH)2D, and iPTH, but not FGF-23, phosphorus and urine calcium, respond to vitamin D supplementation in a time- and dose-response manner. By monthly dosing, 2000 IU appears to be sufficient in achieving a 25(OH)D level of 30 ng/mL in this population. However, importantly, 4000 IU, rather than 2000 IU, seems to suppress iPTH. If replicated, these data might be informative in optimizing vitamin D status and providing individualized dosing recommendation in overweight/obese African Americans. TRIAL REGISTRATION: ClinicalTrials.gov number: NCT01583621, Registered on April 3, 2012.

20.
BMC Genomics ; 5(1): 7, 2004 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-14723793

RESUMO

BACKGROUND: We have recently cloned and characterized a novel gene family named ancient conserved domain protein (ACDP) in humans. To facilitate the functional study of this novel gene family, we have cloned and characterized Acdp, the mouse homologue of the human ACDP gene family. RESULTS: The four Acdp genes (Acdp1, Acdp2, Acdp3 and Acdp4) contain 3,631 bp, 3,244 bp, 2,684 bp and 2,743 bp of cDNA sequences, and encode deduced proteins of 951, 874, 713 and 771 amino acids, respectively. The mouse Acdp genes showed very strong homologies (>90%) in both nucleotide and amino acid sequences to their human counterparts. In addition, both nucleotide and amino acid sequences within the Ancient Conserved Domain (ACD) are highly conserved in many different taxonomic species. Particularly, Acdp proteins showed very strong AA homologies to the bacteria CorC protein (35% AA identity with 55% homology), which is involved in magnesium and cobalt efflux. The Acdp genes are widely expressed in all tissues tested except for Acdp1, which is only highly expressed in the brain with low levels of expression in kidney and testis. Immunostaining of Acdp1 in hippocampus neurons revealed a predominant localization on the plasma membrane. CONCLUSION: The Acdp genes are evolutionarily conserved in diverse species and ubiquitously expressed throughout development and adult tissues suggesting that Acdp may be an essential gene. Acdp showed strong homology to bacteria CorC protein and predominantly localized on the plasma membrane. These results suggest that Acdp is probably a family of proteins involved in ion transport in mammalian cells


Assuntos
Proteínas de Transporte/genética , Família Multigênica/genética , Células 3T3 , Sequência de Aminoácidos , Animais , Northern Blotting , Western Blotting , Encéfalo/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Mapeamento Cromossômico , Cromossomos de Mamíferos/genética , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Perfilação da Expressão Gênica , Humanos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Microscopia Confocal , Dados de Sequência Molecular , Células PC12 , Filogenia , Ratos , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
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