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1.
Am J Physiol Endocrinol Metab ; 327(3): E357-E370, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39017680

RESUMO

Familial partial lipodystrophy 3 (FPLD3) is a rare genetic disorder caused by loss-of-function mutations in the PPARG gene, characterized by a selective absence of subcutaneous fat and associated metabolic complications. However, the molecular mechanisms of FPLD3 remain unclear. In this study, we recruited a 17-yr-old Chinese female with FPLD3 and her family, identifying a novel PPARG frameshift mutation (exon 4: c.418dup: p.R140Kfs*7) that truncates the PPARγ protein at the seventh amino acid, significantly expanding the genetic landscape of FPLD3. By performing next-generation sequencing of circular RNAs (circRNAs), microRNAs (miRNAs), and mRNAs in plasma exosomes, we discovered 59 circRNAs, 57 miRNAs, and 299 mRNAs were significantly altered in the mutation carriers compared with the healthy controls. Integration analysis highlighted that the circ_0001597-miR-671-5p pair and 18 mRNAs might be incorporated into the metabolic regulatory networks of the FPLD3 induced by the novel PPARG mutation. Functional annotation suggested that these genes were significantly enriched in glucose- and lipid metabolism-related pathways. Among the circRNA-miRNA-mRNA network, we identified two critical regulators, early growth response-1 (EGR1), a key transcription factor known for its role in insulin signaling pathways and lipid metabolism, and 1-acylglycerol-3-phosphate O-acyltransferase 3 (AGPAT3), which gets involved in the biosynthesis of triglycerides and lipolysis. Circ_0001597 regulates the expression of these genes through miR-671-5p, potentially contributing to the pathophysiology of FPLD3. Overall, this study clarified a circulating exosomal circRNA-miRNA-mRNA network in a FPLD3 family with a novel PPARG mutation, providing evidence for exploring promising biomarkers and developing novel therapeutic strategies for this rare genetic disorder.NEW & NOTEWORTHY Through the establishment of a ceRNA regulatory networks in a novel PPARG frameshift mutation c.418dup-induced FPLD3 pedigree, this study reveals that circ_0001597 may contribute to the pathophysiology of FPLD3 by sequestering miR-671-5p to regulate the expression of EGR1 and AGPAT3, pivotal genes situated in the triglyceride (TG) synthesis and lipolysis pathways. Current findings expand our molecular understanding of adipose tissue dysfunction, providing potential blood biomarkers and therapeutic avenues for lipodystrophy and associated metabolic complications.


Assuntos
Exossomos , Mutação da Fase de Leitura , Lipodistrofia Parcial Familiar , MicroRNAs , PPAR gama , RNA Circular , RNA Mensageiro , Humanos , Feminino , MicroRNAs/genética , MicroRNAs/sangue , PPAR gama/genética , RNA Circular/genética , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Adolescente , Lipodistrofia Parcial Familiar/genética , Exossomos/genética , Exossomos/metabolismo , Linhagem , Redes Reguladoras de Genes
2.
Angew Chem Int Ed Engl ; 62(11): e202215802, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36650422

RESUMO

The polysulfide (PS) dissolution and low conductivity of lithium sulfides (Li2 S) are generally considered the main reasons for limiting the reversible capacity of the lithium-sulfur (Li-S) system. However, as the inevitable intermediate between PSs and Li2 S, lithium disulfide (Li2 S2 ) evolutions are always overlooked. Herein, Li2 S2 evolutions are monitored from the operando measurements on the pouch cell level. Results indicate that Li2 S2 undergoes slow electrochemical reduction and chemical disproportionation simultaneously during the discharging process, leading to further PS dissolution and Li2 S generation without capacity contribution. Compared with the fully oxidized Li2 S, Li2 S2 still residues at the end of the charging state. Therefore, instead of the considered Li2 S and PSs, slow electrochemical conversions and side chemical reactions of Li2 S2 are the determining factors in limiting the sulfur utilization, corresponding to the poor reversible capacity of Li-S batteries.

3.
Horm Metab Res ; 54(1): 12-19, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34986495

RESUMO

The aim of the work was to explore the correlation between thyroid hormones and coronary atherosclerotic severity. This cross-sectional study included 340 euthyroid patients who underwent diagnostic coronary artery angiography (CAG). Gensini Score (GS) was applied to assess the severity of coronary atherosclerosis. Thyroid hormones and routine biochemical parameters were measured. The associations between thyroid hormones and coronary atherosclerosis severity were analyzed. Thyroid hormones levels or parameters were taken as both continuous variables and tertiles into analysis, and the lowest tertile was usually used as the reference (OR=1) for medium and highest tertiles. Free triiodothyronine (FT3) level was associated with GS≥22 (Median GS) in Model I adjusted for age and sex [Continuous: OR=0.46, 95% CI (0.23, 0.92), p=0.029; Tertile 3: OR=0.54, 95% CI (0.30, 0.97), p=0.038], and Model II adjusted for all known risk factors of coronary artery disease (CAD) [Continuous: OR=0.44, 95% CI (0.20, 0.95), p=0.036; Tertile 3: OR=0.49, 95% CI (0.25, 0.96), p=0.039]. Subjects with highest tertile of FT3 to free thyroxine (FT4) ratio (FT3/FT4 ratio) appeared to have the remarkably decreased risk of CAD in both Non-adjusted Model [OR=0.49, 95% CI (0.24, 0.98), p=0.044] and Model I [OR=0.45, 95% CI (0.22, 0.93), p=0.031]. Higher FT3 level within normal range was independently and negatively associated with severity of coronary atherosclerosis. Besides, FT3/FT4 ratio was remarkably correlated with the prevalence of CAD in euthyroid population.


Assuntos
Aterosclerose/sangue , Aterosclerose/patologia , Síndromes do Eutireóideo Doente/sangue , Síndromes do Eutireóideo Doente/patologia , Índice de Gravidade de Doença , Hormônios Tireóideos/sangue , Aterosclerose/diagnóstico , Feminino , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Análise de Regressão , Medição de Risco , Fatores de Risco , Tri-Iodotironina/sangue
4.
Eur J Neurosci ; 53(8): 2532-2540, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33595911

RESUMO

Diabetes mellitus is a metabolic disorder that can lead to cognitive dysfunction. The hippocampus plays an important role in the cognitive function. Research has identified correlations between hippocampal impairment and diabetes, yet their intermediate remains unclear. Soluble epoxide hydrolase (sEH) is an enzyme that degrades epoxyeicosatrienoic acids (EETs), which have multiple protective effects by suppressing inflammation, apoptosis and oxidative stress. In this study, under diabetic conditions both hippocampal injury and cognitive decline are accompanied by upregulation of sEH. Moreover, the sEH inhibitor trans-4-[4-(3-adamantan-1-y1-ureido)-cyclohexyloxy]-benzoic acid (t-AUCB) prevents cognitive dysfunction and decreased ROS accumulation and apoptosis in the diabetic hippocampus. t-AUCB treatment restored neuronal synaptic plasticity by restoring the expression of the postsynaptic proteins Postsynaptic density protein-95 (PSD95) and N-methyl-d-aspartate receptor subunit 2B (NR2B), the levels of which were positively correlated with Proline-rich tyrosine kinase 2 (Pyk2) levels under diabetic conditions. Thus, we suggest that hippocampal protection via sEH inhibition might be a potential therapeutic approach to attenuate the progression of cognitive decline in diabetes.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Animais , Inibidores Enzimáticos , Epóxido Hidrolases/metabolismo , Hipocampo/metabolismo , Camundongos , Neurônios/metabolismo
5.
Biochem Biophys Res Commun ; 524(2): 354-359, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32001002

RESUMO

Diabetes mellitus is a metabolic disorder that can lead to blood-brain barrier (BBB) disruption and cognitive decline. However, the mechanisms of BBB breakdown in diabetes are still unclear. Soluble epoxide hydrolase (sEH) is an enzyme that degrades epoxyeicosatrienoic acids (EETs), which have multiple protective effects on vascular structure and functions. In the current study, we showed increased vascular permeability of the BBB, which was accompanied by upregulation of sEH and downregulation of 14,15-EET. Moreover, the sEH inhibitor t-AUCB restored diabetic BBB integrity in vivo, and 14,15-EET prevented ROS accumulation and MEC injury in vitro. t-AUCB or 14,15-EET treatment provoked AMPK/HO-1 activation under diabetic conditions in vivo and in vitro. Thus, we suggest that decreased EET degradation by sEH inhibition might be a potential therapeutic approach to attenuate the progression of BBB injury in diabetic mice via AMPK/HO-1 pathway activation.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Diabetes Mellitus Tipo 2/complicações , Epóxido Hidrolases/antagonistas & inibidores , Substâncias Protetoras/uso terapêutico , Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Ácido 8,11,14-Eicosatrienoico/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Modelos Animais de Doenças , Inibidores Enzimáticos/uso terapêutico , Epóxido Hidrolases/metabolismo , Heme Oxigenase-1/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
6.
Metab Brain Dis ; 35(8): 1431-1432, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33064265

RESUMO

In the original published article: A wrong GFAP immunohistochemistry staining image was inadvertently chosen to present as Control group image (the published Fig.1B).

7.
Exp Cell Res ; 363(2): 171-178, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29294308

RESUMO

Diabetes, characterized by chronic hyperglycemia, is known to induce synaptic degeneration in the brain, thereby resulting in cognitive dysfunction. Thrombospondin-1(TSP-1), the secreted protein produced by astrocytes, plays a crucial role in promoting synapse formation. Toll-like receptor 9 (TLR9) has been widely known to initiate the innate immune response. We recently reported TLR9 activation in neurons results in tau hyperphosphorylation induced by HG in vitro. Its activation has been also considered to mediate oxidative stress and astrocytic dysfunction under pathological circumstance. However, whether astrocytic TSP-1 alteration plays a role in synaptic protein loss under high glucose condition and whether TLR9 activation is involved in this process have not been reported. In this study, we found that primary mouse astrocytes incubated in high glucose (30mM) induced a significant decreased TSP-1 secretion and increased intracellular contents of TSP-1 without affecting transcription level. Addition of conditioned medium from high glucose (30mM) treated astrocytes to the primary neurons exhibited reduced synaptic proteins expression, which was attenuated by treatment with exogenous rTSP-1. In addition, we demonstrated that TLR9 activation along with reactive oxygen species (ROS) generation in astrocytes was induced by high glucose (30mM). Furthermore, we explored the relationship between TLR9 activation and TSP-1 production. Both TLR9 deficiency and the antioxidant N-acetyl-L-cysteine treatment improved altered intra- and extracellular TSP-1 levels under high glucose condition. Together, our findings suggest that high glucose (30mM) impairs TSP-1 secretion from astrocytes, which depends on astrocytic dysfunction associated with TLR9 activation mediated ROS signaling, ultimately contributing to the synaptic proteins loss.


Assuntos
Astrócitos/metabolismo , Glucose/farmacologia , Neurônios/metabolismo , Trombospondina 1/metabolismo , Receptor Toll-Like 9/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Células Cultivadas , Meios de Cultivo Condicionados , Feminino , Glucose/metabolismo , Masculino , Camundongos , Sinapses/metabolismo
8.
J Cell Mol Med ; 22(12): 6087-6098, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30246940

RESUMO

Diabetes is considered as a risk for cognitive decline, which is characterized by neurodegenerative alteration and innate immunity activation. Recently, complement 3 (C3), the critical central component of complement system, has been reported to play a key role in neurodegenerative alterations under pathological condition. Receptor for advanced glycation end products (RAGE) activation is confirmed to mediate several inflammatory cytokines production. However, whether C3 activation participates in the diabetic neuropathology and whether this process is regulated by RAGE activation remains unknown. The present study aimed to investigate the role of C3 in streptozotocin-induced diabetic mice and high glucose-induced primary astrocytes and the underlying modulatory mechanisms. The decreased synaptophysin density and increased C3 deposition at synapses were observed in the diabetic brain compared to the control brain. Furthermore, the elevated C3 was co-localized with GFAP-positive astrocytes in the diabetic brain slice in vivo and high glucose-induced astrocytes culture in vitro. Diabetes/high glucose-induced up-regulation of C3 expression at gene, protein and secretion levels, which were attenuated by pre-treatment with RAGE, p38MAPK and NF-κB inhibitors separately. These results demonstrate that high glucose induces C3 up-regulation via RAGE- p38MAPK-NF-κB signalling in vivo and in vitro, which might be associated with synaptic protein loss.


Assuntos
Complemento C3/genética , Diabetes Mellitus Experimental/genética , Diabetes Mellitus/genética , Receptor para Produtos Finais de Glicação Avançada/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Células Cultivadas , Ativação do Complemento/efeitos dos fármacos , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Diabetes Mellitus Experimental/patologia , Glucose/administração & dosagem , Produtos Finais de Glicação Avançada/genética , Humanos , Sistema de Sinalização das MAP Quinases/genética , Camundongos , NF-kappa B/genética , Sinapses/genética , Sinapses/metabolismo , Fator de Transcrição RelA/genética
9.
Exp Cell Res ; 359(2): 312-318, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28803064

RESUMO

Diabetic encephalopathy (DE) is one of the most common complications of diabetes. The major pathological variations include neurofibrillary tangles (NFTs), which are caused by tau hyperphosphorylation, and senile plaques (SPs) consisting of amyloid ß- protein(Aß) deposits. In recent years, DE research studies have focused on exploring the activation of the inflammatory signaling pathway in immune cells. Toll-like receptor 9 (TLR9) is well known to regulate the inflammatory reactions in immune processes. During the tau hyperphosphorylation process, TLR9 in microglia plays bidirectional roles. However, no studies have clearly demonstrated the relationship between TLR9 and tau hyperphosphorylation in neurons. Based on our experiments, we found significant increase in TLR9 expression in neurons and an increase in tau hyperphosphorylation in high-glucose media. However, these alterations can be reversed by TLR9 inhibitor. Furthermore, we specifically inhibited the activation of P38mitogenactivated protein kinase(P38MAPK) and found an effective decrease in tau hyperphosphorylation. This effect is likely related to Unc93b1. Meanwhile, High glucose levels can induce neuronal apoptosis via the TLR9 signaling pathway. Our studies are the first to reveal that high glucose can regulate tau hyperphosphorylation and neuronal apoptosis via TLR9-P38MAPK signaling pathway. These findings provide a new method for studying the mechanism underlying DE.


Assuntos
Glucose/toxicidade , Neurônios/efeitos dos fármacos , Receptor Toll-Like 9/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas tau/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Regulação da Expressão Gênica , Hipocampo , Imidazóis/farmacologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Neurônios/citologia , Neurônios/metabolismo , Oligonucleotídeos/genética , Oligonucleotídeos/metabolismo , Fosforilação/efeitos dos fármacos , Cultura Primária de Células , Piridinas/farmacologia , Transdução de Sinais , Receptor Toll-Like 9/agonistas , Receptor Toll-Like 9/antagonistas & inibidores , Receptor Toll-Like 9/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas tau/metabolismo
10.
Metab Brain Dis ; 32(3): 903-912, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28357639

RESUMO

Diabetic encephalopathy is characterized by cognitive impairment and neuroinflammation, deficient neurotrophic support, and neuronal and synaptic loss. Ghrelin, a 28 amino acid peptide, is associated with neuromodulation and cognitive improvement, which has been considered as a potential protective agent for several neurodegenerative diseases. Here we sought to investigate the role of ghrelin in preventing diabetic-related neuropathology. We found that ghrelin attenuated astrocytic activation and reduced levels of interleukin-6 and tumor necrosis factor-α in streptozotocin-induced diabetic rats. In addition, ghrelin inhibited p38 mitogen-associated protein kinase activation. The upregulation of nerve growth factor (NGF) precursor and matrix metalloproteinase (MMP)-9 and downregulation of mature NGF and MMP-7 in the diabetic brain were reversed by ghrelin. Treatment with ghrelin elevated synaptophysin expression and synaptic density in diabetic rats. Taken together, our results demonstrate that ghrelin ameliorates diabetes-related neurodegeneration by preventing NGF dysmetabolism and synaptic degeneration through regulating MMP levels as well as inhibiting neuroinflammation.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Grelina/administração & dosagem , Hipocampo/metabolismo , Mediadores da Inflamação/metabolismo , Fator de Crescimento Neural/metabolismo , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Diabetes Mellitus Experimental/patologia , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Mediadores da Inflamação/antagonistas & inibidores , Injeções Intraventriculares , Masculino , Ratos , Ratos Sprague-Dawley
11.
Eur J Immunol ; 45(9): 2494-503, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25959978

RESUMO

Type 1 diabetes results from destruction of pancreatic beta cells by autoreactive T cells. Both CD4(+) and CD8(+) T cells have been shown to mediate beta-cell killing. While CD8(+) T cells can directly recognize MHC class I on beta cells, the interaction between CD4(+) T cells and beta cells remains unclear. Genetic association studies have strongly implicated HLA-DQ alleles in human type 1 diabetes. Here we studied MHC class II expression on beta cells in nonobese diabetic mice that were induced to develop diabetes by diabetogenic CD4(+) T cells with T-cell receptors that recognize beta-cell antigens. Acute infiltration of CD4(+) T cells in islets occurred with rapid onset of diabetes. Beta cells from islets with immune infiltration expressed MHC class II mRNA and protein. Exposure of beta cells to IFN-γ increased MHC class II gene expression, and blocking IFN-γ signaling in beta cells inhibited MHC class II upregulation. IFN-γ also increased HLA-DR expression in human islets. MHC class II(+) beta cells stimulated the proliferation of beta-cell-specific CD4(+) T cells. Our study indicates that MHC class II molecules may play an important role in beta-cell interaction with CD4(+) T cells in the development of type 1 diabetes.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Antígenos HLA-DQ/imunologia , Antígenos HLA-DR/imunologia , Células Secretoras de Insulina/imunologia , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Comunicação Celular/imunologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citotoxicidade Imunológica , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patologia , Feminino , Regulação da Expressão Gênica , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/patologia , Interferon gama/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos NOD , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Técnicas de Cultura de Tecidos
12.
Diabetologia ; 58(1): 140-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25301392

RESUMO

AIMS/HYPOTHESIS: Type 1 diabetes results from T cell-mediated destruction of pancreatic beta cells. The mechanisms of beta cell destruction in vivo, however, remain unclear. We aimed to test the relative roles of the main cell death pathways: apoptosis, necrosis and necroptosis, in beta cell death in the development of CD4(+) T cell-mediated autoimmune diabetes. METHODS: We altered expression levels of critical cell death proteins in mouse islets and tested their ability to survive CD4(+) T cell-mediated attack using an in vivo graft model. RESULTS: Loss of the B cell leukaemia/lymphoma 2 (BCL-2) homology domain 3-only proteins BIM, PUMA or BID did not protect beta cells from this death. Overexpression of the anti-apoptotic protein BCL-2 or combined deficiency of the pro-apoptotic multi-BCL2 homology domain proteins BAX and BAK also failed to prevent beta cell destruction. Furthermore, loss of function of the death receptor Fas or its essential downstream signalling molecule Fas-associated death domain (FADD) in islets was also not protective. Using electron microscopy we observed that dying beta cells showed features of necrosis. However, islets deficient in receptor-interacting serine/threonine protein kinase 3 (RIPK3), a critical initiator of necroptosis, were still normally susceptible to CD4(+) T cell-mediated destruction. Remarkably, simultaneous inhibition of apoptosis and necroptosis by combining loss of RIPK3 and overexpression of BCL-2 in islets did not protect them against immune attack either. CONCLUSIONS/INTERPRETATION: Collectively, our data indicate that beta cells die by necrosis in autoimmune diabetes and that the programmed cell death pathways apoptosis and necroptosis are both dispensable for this process.


Assuntos
Autoimunidade/fisiologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/patologia , Linfócitos T/imunologia , Animais , Apoptose/genética , Apoptose/fisiologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Rejeição de Enxerto/genética , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/metabolismo , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Necrose/genética , Necrose/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/fisiologia , Receptores de Morte Celular/genética , Receptores de Morte Celular/fisiologia
13.
Proc Natl Acad Sci U S A ; 108(23): 9554-9, 2011 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-21606371

RESUMO

Endogenous and pharmacologic glucocorticoids (GCs) limit inflammatory cascades initiated by Toll-like receptor (TLR) activation. A long-standing clinical observation has been the delay between GC administration and the manifestation of GC's anti-inflammatory actions. We hypothesized that the GCs would have inhibitory effects that target late temporal pathways that propagate proinflammatory signals. Here we interrogated signal transducer and activator of transcription 1 (STAT1) regulation by GC and its consequences for cytokine production during activation of macrophages with TLR-specific ligands. We found that robust STAT1 activation does not occur until 2-3 h after TLR engagement, and that GC suppression of STAT1 phosphorylation first manifests at this time. GC attenuates TLR4-mediated STAT1 activation only through induction of suppressor of cytokine signaling 1 (SOCS1), which increases throughout the 6-h period after treatment. Inhibition of TLR3-mediated STAT1 activation occurs via two mechanisms, impairment of type I IFN secretion and induction of SOCS1. Our data show that SOCS1 and type I interferons are critical GC targets for regulating STAT1 activity and may account for overall GC effectiveness in inflammation suppression in the clinically relevant time frame.


Assuntos
Glucocorticoides/farmacologia , Interferon-alfa/metabolismo , Macrófagos/efeitos dos fármacos , Fator de Transcrição STAT1/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Receptores Toll-Like/metabolismo , Animais , Western Blotting , Células Cultivadas , Dexametasona/farmacologia , Fator Regulador 3 de Interferon/metabolismo , Interferon beta/farmacologia , Subunidade p40 da Interleucina-12/metabolismo , Interleucina-6/metabolismo , Janus Quinase 2/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Poli I-C/farmacologia , Receptores de Interferon/metabolismo , Fator de Transcrição STAT1/genética , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina/genética
14.
RSC Adv ; 14(33): 23910-23920, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39086518

RESUMO

Hybrid inorganic particles combined with polymers are widely used to modify the properties of polymer membranes. However, the mechanism by which particles affect membranes remains unclear. This study investigates SiO2-hybridized PVDF membranes through molecular dynamic simulation, focusing on the interaction between SiO2 clusters and PVDF chains. It examines the impact of varying SiO2 concentrations (3.5 wt%, 6.8 wt%, 9.9 wt%, 12.8 wt%, and 15.5 wt%) on membrane stability and structure. The results indicate that adding SiO2 can inhibit PVDF chain mobility in the membrane with minimal effect on fractional free volume (FFV), except for altering interactions between PVDF-PVDF, PVDF-SiO2, and SiO2-SiO2, thereby affecting the structure of hybrid membranes. The adsorption and diffusion behavior of water and oil molecules on these membranes were also studied. It was observed that the adsorption energy and diffusion coefficient initially increase and then decrease with increasing SiO2 concentration, reaching an optimum between 6.8 wt% and 12.8 wt%. This phenomenon is attributed to the ability of optimal SiO2 concentrations to create hydrophilic channels in PVDF membranes, enhancing water affinity and reducing oil affinity. Consequently, water permeation through the hybrid membrane is promoted, improving the efficiency of oil/water separation compared to pure PVDF membranes. This research contributes to understanding the function of adding inorganic particles to polymer membranes and provides insights for designing advanced functional hybrid membranes.

15.
Endocrine ; 84(3): 1097-1107, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38396200

RESUMO

PURPOSE: The role of prolactin (PRL) in glucolipid metabolism was inconsistent, and there were few studies on the metabolic role of PRL in obese patients. The study aims to explore association between PRL level and metabolic disorders in male obese patients. METHODS: A retrospective study was conducted. Eighty-nine male patients with obesity were included, and their clinical data were recorded. RESULTS: A total of 89 male obese patients were included in this study. Their average age was 24.5 ± 9.0 years and BMI was 42.8 ± 9.1 kg/m2. The average waist circumference and body fat percentage was 129.6 ± 19.6 cm and 42.9 ± 8.0%, respectively. The median prolactin levels were 10.0 ng/ml (range: 3.93-30.1 ng/ml). 79.0% (49/62) of these patients presented with NAFLD and 77.3% (68/88) of them was dyslipidemia. Further, serum prolactin level was positively correlated with BMI (r = 0.225, P = 0.034), body fat percentage (r = 0.326, P = 0.017), ALT (r = 0.273, P = 0.011) and AST (r = 0.245, P = 0.029). Compared with low PRL group (<10 ng/ml), the incidence of morbid obesity and NAFLD was higher in high PRL group (morbid obesity: 71.1% vs 45.5%, P = 0.018 and NAFLD: 91.2% vs 64.3%, P = 0.013). In addition, the risk of NAFLD and morbid obesity in high PRL group (>10 ng/ml) was higher than low PRL group (OR:5.187, 95%CI 1.194-22.544, P = 0.028 and OR: 4.375, 95% CI 1.595-11.994, P = 0.004). The increased risk of NAFLD and morbid obesity in the high PRL group still existed after adjusting for age and Testosterone. CONCLUSION: Serum prolactin levels were positively associated with deterioration of metabolic indexes in male obese patients, as well as NAFLD and morbid obesity.


Assuntos
Obesidade , Prolactina , Humanos , Masculino , Prolactina/sangue , Adulto , Estudos Retrospectivos , Obesidade/sangue , Obesidade/complicações , Obesidade/epidemiologia , Adulto Jovem , Índice de Massa Corporal , Adolescente , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Pessoa de Meia-Idade , Dislipidemias/sangue , Dislipidemias/epidemiologia , Circunferência da Cintura
16.
J Inflamm Res ; 17: 5723-5740, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39219820

RESUMO

Background: Primary Sjögren's syndrome (pSS) is an autoimmune condition marked by lymphocyte infiltration in the exocrine glands. Our study aimed to identify a novel biomarker for pSS to improve its diagnosis and treatment. Methods: The gene expression profiles of pSS were obtained from the Gene Expression Omnibus (GEO) database. The specific differentially expressed genes (DEGs) were screened by the Least Absolute Shrinkage and Selection Operator (LASSO), Random Forest (RF), and Recursive Feature Elimination with Support Vector Machines (SVM-RFE). A biomarker was picked out based on correlation and diagnostic performance, the connection between the biomarker and clinical traits and immune infiltrating cells was explored, and the biomarker's protein expression level in the serum of pSS patients was detected by enzyme-linked immunosorbent assay (ELISA). The competitive endogenous RNA (ceRNA) network regulated by the biomarker was predicted to verify the reliability of the biomarker in diagnosing pSS. Results: IFI44, XAF1, GBP1, EIF2AK2, IFI27, and IFI6 showed prominent diagnostic ability, with the high accuracy (AUC = 0.859) and significance (R ≥ 0.8) of IFI44 within the training dataset. IFI44 strongly exhibited a negative correlation with resting NK cells, macrophages M0, and eosinophils, and a positive correlation with activated dendritic cells, naive B cells, and activated CD4 memory T cells. Furthermore, IFI44 was significantly positively correlated with clinical traits such as IgG, SSA, SSB, ANA, and ESSDAI, with its protein expression level in the serum of pSS patients being notably elevated compared to controls (p < 0.001). Finally, the ceRNA regulatory network showed that hsa-miR-944, hsa-miR-9-5p, hsa-miR-126-5p, and hsa-miR-335-3p were significantly targeted IFI44, suggesting that IFI44 may serve as a dependable biomarker for pSS. Conclusion: In this study, we dug out IFI44 as a biomarker for pSS, systematically studied the potential regulatory mechanism of IFI44, and verified its reliability as a biomarker for pSS.

17.
J Biol Chem ; 286(7): 5921-33, 2011 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-21159778

RESUMO

The PI3K/Akt pathway is activated in stimulated cells and in many cancers to promote glucose metabolism and prevent cell death. Although inhibition of Akt-mediated cell survival may provide a means to eliminate cancer cells, this survival pathway remains incompletely understood. In particular, unlike anti-apoptotic Bcl-2 family proteins that prevent apoptosis independent of glucose, Akt requires glucose metabolism to inhibit cell death. This glucose dependence may occur in part through metabolic regulation of pro-apoptotic Bcl-2 family proteins. Here, we show that activated Akt relies on glycolysis to inhibit induction of Puma, which was uniquely sensitive to metabolic status among pro-apoptotic Bcl-2 family members and was rapidly up-regulated in glucose-deficient conditions. Importantly, preventing Puma expression was critical for Akt-mediated cell survival, as Puma deficiency protected cells from glucose deprivation and Akt could not readily block Puma-mediated apoptosis. In contrast, the pro-apoptotic Bcl-2 family protein Bim was induced normally even when constitutively active Akt was expressed, yet Akt could provide protection from Bim cytotoxicity. Up-regulation of Puma appeared mediated by decreased availability of mitochondrial metabolites rather than glycolysis itself, as alternative mitochondrial fuels could suppress Puma induction and apoptosis upon glucose deprivation. Metabolic regulation of Puma was mediated through combined p53-dependent transcriptional induction and control of Puma protein stability, with Puma degraded in nutrient-replete conditions and long lived in nutrient deficiency. Together, these data identify a key role for Bcl-2 family proteins in Akt-mediated cell survival that may be critical in normal immunity and in cancer through Akt-dependent stimulation of glycolysis to suppress Puma expression.


Assuntos
Proteínas Reguladoras de Apoptose/biossíntese , Apoptose , Regulação Leucêmica da Expressão Gênica , Glucose/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Supressoras de Tumor/biossíntese , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Sobrevivência Celular/genética , Glucose/genética , Glicólise/genética , Humanos , Células Jurkat , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/genética , Regulação para Cima/genética
18.
Immunol Cell Biol ; 90(2): 243-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21383770

RESUMO

CD8(+) T cells kill pancreatic ß-cells in a cell-cell contact-dependent mechanism in the non-obese diabetic mouse. CD4(+) T lymphocytes are also able to kill pancreatic ß-cells, but they do not directly contact ß-cells and may use another cell type as the actual cytotoxic cell. Natural killer (NK) cells could have this role but it is uncertain whether they are cytotoxic towards ß-cells. Therefore, the requirement for NK cells in ß-cell destruction in the CD4-dependent T-cell antigen receptor transgenic NOD4.1 mice was examined. NK cells failed to kill ß-cells in vitro, even in the absence of major histocompatibility complex class I. We observed only 9.7±1.1% of islet infiltrating NK cells from NOD4.1 mice expressing the degranulation marker CD107a. Diabetogenic CD4(+) T cells transferred disease to NODscid.IL2Rγ(-/-) mice lacking NK cells, indicating that NK cells do not contribute to ß-cell death in vitro or in vivo. However, depletion of NK cells reduced diabetes incidence in NOD4.1 mice, suggesting that NK cells may help to maintain the right environment for cytotoxicity of effector cells.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Células Secretoras de Insulina/imunologia , Células Matadoras Naturais/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular , Diabetes Mellitus Tipo 1/genética , Antígenos HLA-A/imunologia , Células Secretoras de Insulina/citologia , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Complexo Principal de Histocompatibilidade , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Proteínas Associadas à Matriz Nuclear/metabolismo , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Receptores de Interleucina-2/genética
19.
ACS Appl Mater Interfaces ; 14(5): 6499-6506, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35080363

RESUMO

Dendrite formation is an important issue for the metal anode-based battery system. The traditional perception that Mg metal anode does not grow dendrite during operation has been challenged recently. Herein, we investigate the Mg electrodeposition behavior in a 0.3 M all-phenyl-complex (APC) electrolyte and confirm that Mg dendrites are readily formed at high current densities. A semiquantitative model indicates that the Mg-ion concentration on the electrode surface, limited by the intrinsic diffusion coefficient of the Mg cation group, decreases with increasing current density, resulting in an extra concentration polarization. However, Mg deposition at the tip of a protrusion on the electrode surface is hardly affected by the concentration polarization, and thus dendrite growth is more prone to occur at the tips. We find that the addition of LiCl in conventional APC electrolytes can suppress the Mg dendrite formation, mainly as a result of the enhanced Mg cation diffusion coefficient due to the influence of the LiCl additive, rather than the less pronounced electrostatic shield effect provided by Li cations.

20.
Aging Cell ; 21(7): e13659, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35712918

RESUMO

Aging-related sarcopenia is currently the most common sarcopenia. The main manifestations are skeletal muscle atrophy, replacement of muscle fibers with fat and fibrous tissue. Excessive fibrosis can impair muscle regeneration and function. Lysyl oxidase-like 2 (LOXL2) has previously been reported to be involved in the development of various tissue fibrosis. Here, we investigated the effects of LOXL2 inhibitor on D-galactose (D-gal)-induced skeletal muscle fibroblast cells and mice. Our molecular and physiological studies show that treatment with LOXL2 inhibitor can alleviate senescence, fibrosis, and increased production of reactive oxygen species in fibroblasts caused by D-gal. These effects are related to the inhibition of the TGF-ß1/p38 MAPK pathway. Furthermore, in vivo, mice treatment with LOXL2 inhibitor reduced D-gal-induced skeletal muscle fibrosis, partially enhanced skeletal muscle mass and strength and reduced redox balance disorder. Taken together, these data indicate the possibility of using LOXL2 inhibitors to prevent aging-related sarcopenia, especially with significant fibrosis.


Assuntos
Galactose , Sarcopenia , Aminoácido Oxirredutases/metabolismo , Aminoácido Oxirredutases/farmacologia , Animais , Fibrose , Galactose/farmacologia , Camundongos , Músculo Esquelético/metabolismo , Proteína-Lisina 6-Oxidase/farmacologia , Sarcopenia/induzido quimicamente , Sarcopenia/tratamento farmacológico , Sarcopenia/patologia
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