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1.
Brain Behav Immun Health ; 32: 100675, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37600600

RESUMO

The COVID-19 pandemic has resulted in significant morbidity and mortality worldwide. Management of the pandemic has relied mainly on SARS-CoV-2 vaccines, while alternative approaches such as meditation, shown to improve immunity, have been largely unexplored. Here, we probe the relationship between meditation and COVID-19 disease and directly test the impact of meditation on the induction of a blood environment that modulates viral infection. We found a significant inverse correlation between length of meditation practice and SARS-CoV-2 infection as well as accelerated resolution of symptomology of those infected. A meditation "dosing" effect was also observed. In cultured human lung cells, blood from experienced meditators induced factors that prevented entry of pseudotyped viruses for SARS-CoV-2 spike protein of both the wild-type Wuhan-1 virus and the Delta variant. We identified and validated SERPINA5, a serine protease inhibitor, as one possible protein factor in the blood of meditators that is necessary and sufficient for limiting pseudovirus entry into cells. In summary, we conclude that meditation can enhance resiliency to viral infection and may serve as a possible adjuvant therapy in the management of the COVID-19 pandemic.

3.
Am J Pathol ; 191(8): 1474-1486, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34294193

RESUMO

Humans cannot synthesize the common mammalian sialic acid N-glycolylneuraminic acid (Neu5Gc) because of an inactivating deletion in the cytidine-5'-monophospho-(CMP)-N-acetylneuraminic acid hydroxylase (CMAH) gene responsible for its synthesis. Human Neu5Gc deficiency can lead to development of anti-Neu5Gc serum antibodies, the levels of which can be affected by Neu5Gc-containing diets and by disease. Metabolic incorporation of dietary Neu5Gc into human tissues in the face of circulating antibodies against Neu5Gc-bearing glycans is thought to exacerbate inflammation-driven diseases like cancer and atherosclerosis. Probing of sera with sialoglycan arrays indicated that patients with Duchenne muscular dystrophy (DMD) had a threefold increase in overall anti-Neu5Gc antibody titer compared with age-matched controls. These antibodies recognized a broad spectrum of Neu5Gc-containing glycans. Human-like inactivation of the Cmah gene in mice is known to modulate severity in a variety of mouse models of human disease, including the X chromosome-linked muscular dystrophy (mdx) model for DMD. Cmah-/-mdx mice can be induced to develop anti-Neu5Gc-glycan antibodies as humans do. The presence of anti-Neu5Gc antibodies, in concert with induced Neu5Gc expression, correlated with increased severity of disease pathology in Cmah-/-mdx mice, including increased muscle fibrosis, expression of inflammatory markers in the heart, and decreased survival. These studies suggest that patients with DMD who harbor anti-Neu5Gc serum antibodies might exacerbate disease severity when they ingest Neu5Gc-rich foods, like red meats.


Assuntos
Autoanticorpos/sangue , Distrofia Muscular de Duchenne/imunologia , Distrofia Muscular de Duchenne/patologia , Ácidos Neuramínicos/sangue , Ácidos Neuramínicos/imunologia , Animais , Autoanticorpos/imunologia , Autoantígenos/imunologia , Criança , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Endogâmicos mdx , Camundongos Knockout , Distrofia Muscular de Duchenne/sangue
4.
Cell Cycle ; 18(11): 1268-1280, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31116089

RESUMO

Caveolin-1 (Cav-1) is an integral membrane protein that plays an important role in proliferative and terminally differentiated cells. As a structural component of Caveolae, Cav-1 interacts with signaling molecules via a caveolin scaffolding domain (CSD) regulating cell signaling. Recent reports have shown that Cav-1 is a negative regulator in tumor metastasis. Therefore, we hypothesize that Cav-1 inhibits cell migration through its CSD. HeLa cells were engineered to overexpress Cav-1 (Cav-1 OE), Cav-1 without a functional CSD (∆CSD), or enhanced green fluorescent protein (EGFP) as a control. HeLa cell migration was suppressed in Cav-1 OE cells while ∆CSD showed increased migration, which corresponded to a decrease in the tight junction protein, zonula occludens (ZO-1). The migration phenotype was confirmed in multiple cancer cell lines. Phosphorylated STAT-3 was decreased in Cav-1 OE cells compared to control and ∆CSD cells; reducing STAT-3 expression alone decreased cell migration. ∆CSD blunted HeLa proliferation by increasing the number of cells in the G2/M phase of the cell cycle. Overexpressing the CSD peptide alone suppressed HeLa cell migration and inhibited pSTAT3. These findings suggest that Cav-1 CSD may be critical in controlling the dynamic phenotype of cancer cells by facilitating the interaction of specific signal transduction pathways, regulating STAT3 and participating in a G2/M checkpoint. Modulating the CSD and targeting specific proteins may offer potential new therapies in the treatment of cancer metastasis.


Assuntos
Caveolina 1/química , Caveolina 1/fisiologia , Movimento Celular/genética , Neoplasias/patologia , Caveolina 1/genética , Células Cultivadas , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Células HCT116 , Células HT29 , Células HeLa , Humanos , Metástase Neoplásica , Neoplasias/genética , Domínios Proteicos/genética , Fator de Transcrição STAT3/metabolismo , Deleção de Sequência
5.
Am J Physiol Regul Integr Comp Physiol ; 317(1): R160-R168, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31091156

RESUMO

Sepsis is a major clinical challenge, with therapy limited to supportive interventions. Therefore, the search for novel remedial approaches is of great importance. We addressed whether hyperbaric oxygen therapy (HBOT) could improve the outcome of sepsis using an acute experimental mouse model. Sepsis was induced in male CD-1 mice by cecal ligation and puncture (CLP) tailored to result in 80-90% mortality within 72 h of the insult. After CLP, mice were randomized into two groups receiving HBOT or not at different times after the initial insult or subjected to multiple HBOT treatments. HBOT conditions were 98% oxygen pressurized to 2.4 atmospheres for 1 h. HBOT within 1 h after CLP resulted in 52% survival in comparison with mice that did not receive the treatment (13% survival). Multiple HBOT at 1 and 6 h or 1, 6, and 21 h displayed an increase in survival of >50%, but they were not significantly different from a single treatment after 1 h of CLP. Treatments at 6 or 21 h after CLP, excluding the 1 h of treatment, did not show any protective effect. Early HBO treatment did not modify bacterial counts after CLP, but it was associated with decreased expression of TNF-α, IL-6, and IL-10 expression in the liver within 3 h after CLP. The decrease of cytokine expression was reproduced in cultured macrophages after exposure to HBOT. Early HBOT could be of benefit in the treatment of sepsis, and the protective mechanism may be related to a reduction in the systemic inflammatory response.


Assuntos
Modelos Animais de Doenças , Oxigenoterapia Hiperbárica , Sepse/terapia , Animais , Ceco/lesões , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica , Ligadura , Lipopolissacarídeos/toxicidade , Macrófagos/metabolismo , Masculino , Camundongos , Mitocôndrias/metabolismo , Consumo de Oxigênio , Punções
6.
Proc Biol Sci ; 285(1886)2018 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-30209232

RESUMO

Compared to other primates, humans are exceptional long-distance runners, a feature that emerged in genus Homo approximately 2 Ma and is classically attributed to anatomical and physiological adaptations such as an enlarged gluteus maximus and improved heat dissipation. However, no underlying genetic changes have currently been defined. Two to three million years ago, an exon deletion in the CMP-Neu5Ac hydroxylase (CMAH) gene also became fixed in our ancestral lineage. Cmah loss in mice exacerbates disease severity in multiple mouse models for muscular dystrophy, a finding only partially attributed to differences in immune reactivity. We evaluated the exercise capacity of Cmah-/- mice and observed an increased performance during forced treadmill testing and after 15 days of voluntary wheel running. Cmah-/- hindlimb muscle exhibited more capillaries and a greater fatigue resistance in situ Maximal coupled respiration was also higher in Cmah null mice ex vivo and relevant differences in metabolic pathways were also noted. Taken together, these data suggest that CMAH loss contributes to an improved skeletal muscle capacity for oxygen use. If translatable to humans, CMAH loss could have provided a selective advantage for ancestral Homo during the transition from forest dwelling to increased resource exploration and hunter/gatherer behaviour in the open savannah.


Assuntos
Camundongos/fisiologia , Oxigenases de Função Mista/metabolismo , Corrida , Animais , Masculino , Camundongos/genética , Camundongos Knockout , Oxigenases de Função Mista/deficiência , Condicionamento Físico Animal
7.
Chembiochem ; 18(13): 1155-1171, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28423240

RESUMO

About 2-3 million years ago, Alu-mediated deletion of a critical exon in the CMAH gene became fixed in the hominin lineage ancestral to humans, possibly through a stepwise process of selection by pathogen targeting of the CMAH product (the sialic acid Neu5Gc), followed by reproductive isolation through female anti-Neu5Gc antibodies. Loss of CMAH has occurred independently in some other lineages, but is functionally intact in Old World primates, including our closest relatives, the chimpanzee. Although the biophysical and biochemical ramifications of losing tens of millions of Neu5Gc hydroxy groups at most cell surfaces remains poorly understood, we do know that there are multiscale effects functionally relevant to both sides of the host-pathogen interface. Hominin CMAH loss might also contribute to understanding human evolution, at the time when our ancestors were starting to use stone tools, increasing their consumption of meat, and possibly hunting. Comparisons with chimpanzees within ethical and practical limitations have revealed some consequences of human CMAH loss, but more has been learned by using a mouse model with a human-like Cmah inactivation. For example, such mice can develop antibodies against Neu5Gc that could affect inflammatory processes like cancer progression in the face of Neu5Gc metabolic incorporation from red meats, display a hyper-reactive immune system, a human-like tendency for delayed wound healing, late-onset hearing loss, insulin resistance, susceptibility to muscular dystrophy pathologies, and increased sensitivity to multiple human-adapted pathogens involving sialic acids. Further studies in such mice could provide a model for other human-specific processes and pathologies involving sialic acid biology that have yet to be explored.


Assuntos
Genoma , Perda Auditiva/metabolismo , Oxigenases de Função Mista/genética , Distrofias Musculares/metabolismo , Neoplasias/metabolismo , Ácidos Neuramínicos/metabolismo , Animais , Autoanticorpos/biossíntese , Evolução Biológica , Suscetibilidade a Doenças , Expressão Gênica , Perda Auditiva/genética , Perda Auditiva/imunologia , Perda Auditiva/patologia , Humanos , Resistência à Insulina , Camundongos , Oxigenases de Função Mista/deficiência , Oxigenases de Função Mista/imunologia , Distrofias Musculares/genética , Distrofias Musculares/imunologia , Distrofias Musculares/patologia , Mutação , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/patologia , Ácidos Neuramínicos/química , Ácidos Neuramínicos/imunologia , Pan troglodytes
8.
J Immunol ; 198(6): 2366-2373, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28148732

RESUMO

Humans and chimpanzees are more sensitive to endotoxin than are mice or monkeys, but any underlying differences in inflammatory physiology have not been fully described or understood. We studied innate immune responses in Cmah-/- mice, emulating human loss of the gene encoding production of Neu5Gc, a major cell surface sialic acid. CMP-N-acetylneuraminic acid hydroxylase (CMAH) loss occurred ∼2-3 million years ago, after the common ancestor of humans and chimpanzees, perhaps contributing to speciation of the genus HomoCmah-/- mice manifested a decreased survival in endotoxemia following bacterial LPS injection. Macrophages from Cmah-/- mice secreted more inflammatory cytokines with LPS stimulation and showed more phagocytic activity. Macrophages and whole blood from Cmah-/- mice also killed bacteria more effectively. Metabolic reintroduction of Neu5Gc into Cmah-/- macrophages suppressed these differences. Cmah-/- mice also showed enhanced bacterial clearance during sublethal lung infection. Although monocytes and monocyte-derived macrophages from humans and chimpanzees exhibited marginal differences in LPS responses, human monocyte-derived macrophages killed Escherichia coli and ingested E. coli BioParticles better. Metabolic reintroduction of Neu5Gc into human macrophages suppressed these differences. Although multiple mechanisms are likely involved, one cause is altered expression of C/EBPß, a transcription factor affecting macrophage function. Loss of Neu5Gc in Homo likely had complex effects on immunity, providing greater capabilities to clear sublethal bacterial challenges, possibly at the cost of endotoxic shock risk. This trade-off may have provided a selective advantage when Homo transitioned to butchery using stone tools. The findings may also explain why the Cmah-/- state alters severity in mouse models of human disease.


Assuntos
Endotoxemia/imunologia , Escherichia coli/fisiologia , Inflamação/imunologia , Macrófagos/imunologia , Oxigenases de Função Mista/metabolismo , Animais , Bacteriólise/genética , Evolução Biológica , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Feminino , Humanos , Lipopolissacarídeos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxigenases de Função Mista/genética , Pan troglodytes , Fagocitose/genética
9.
Cell Stress Chaperones ; 19(6): 877-86, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24789271

RESUMO

Heat shock proteins (hsp) are well recognized for their protein folding activity. Additionally, hsp expression is enhanced during stress conditions to preserve cellular homeostasis. Hsp are also detected outside cells, released by an active mechanism independent of cell death. Extracellular hsp appear to act as signaling molecules as part of a systemic response to stress. Extracellular hsp do not contain a consensus signal for their secretion via the classical ER-Golgi compartment. Therefore, they are likely exported by an alternative mechanism requiring translocation across the plasma membrane. Since Hsp70, the major inducible hsp, has been detected on surface of stressed cells, we propose that membrane interaction is the first step in the export process. The question that emerges is how does this charged cytosolic protein interact with lipid membranes? Prior studies have shown that Hsp70 formed ion conductance pathways within artificial lipid bilayers. These early observations have been extended herewith using a liposome insertion assay. We showed that Hsp70 selectively interacted with negatively charged phospholipids, particularly phosphatidyl serine (PS), within liposomes, which was followed by insertion into the lipid bilayer, forming high-molecular weight oligomers. Hsp70 displayed a preference for less fluid lipid environments and the region embedded into the lipid membrane was mapped toward the C-terminus end of the molecule. The results from our studies provide evidence of an unexpected ability of a large, charged protein to become inserted into a lipid membrane. This observation provides a new paradigm for the interaction of proteins with lipid environments. In addition, it may explain the export mechanism of an increasing number of proteins that lack the consensus secretory signals.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Fosfatidilserinas/metabolismo , Sequência de Aminoácidos , Proteínas de Choque Térmico HSP70/química , Lipossomos , Fluidez de Membrana , Dados de Sequência Molecular , Peso Molecular , Fosfatidilserinas/química , Estrutura Terciária de Proteína , Transporte Proteico , Proteínas Recombinantes/metabolismo , Propriedades de Superfície , Fatores de Tempo
10.
PLoS One ; 9(2): e88226, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24505439

RESUMO

The expression of N-glycolylneuraminic acid (Neu5Gc) and the cytotoxic T cell (CT) carbohydrate can impact the severity of muscular dystrophy arising from the loss of dystrophin in mdx mice. Here, we describe the expression of these two glycans in skeletal muscles of dogs and humans with or without dystrophin-deficiency. Neu5Gc expression was highly reduced (>95%) in muscle from normal golden retriever crosses (GR, n = 3) and from golden retriever with muscular dystrophy (GRMD, n = 5) dogs at multiple ages (3, 6 and 13 months) when compared to mouse muscle, however, overall sialic acid expression in GR and GRMD muscles remained high at all ages. Neu5Gc was expressed on only a minority of GRMD satellite cells, CD8⁺ T lymphocytes and macrophages. Human muscle from normal (no evident disease, n = 3), Becker (BMD, n = 3) and Duchenne (DMD, n = 3) muscular dystrophy individuals had absent to very low Neu5Gc staining, but some punctate intracellular muscle staining was present in BMD and DMD muscles. The CT carbohydrate was localized to the neuromuscular junction in GR muscle, while GRMD muscles had increased expression on a subset of myofibers and macrophages. In humans, the CT carbohydrate was ectopically expressed on the sarcolemmal membrane of some BMD muscles, but not normal human or DMD muscles. These data are consistent with the notion that altered Neu5Gc and CT carbohydrate expression may modify disease severity resulting from dystrophin deficiency in dogs and humans.


Assuntos
Distrofina/genética , Músculo Esquelético/patologia , Distrofia Muscular Animal/genética , Distrofia Muscular Animal/patologia , Ácidos Neuramínicos/análise , Linfócitos T Citotóxicos/patologia , Animais , Cães , Feminino , Deleção de Genes , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Músculo Esquelético/metabolismo , Distrofia Muscular Animal/metabolismo , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/patologia , Ácidos Neuramínicos/metabolismo , Linfócitos T Citotóxicos/metabolismo
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