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1.
Chemistry ; 30(4): e202303089, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-37966430

RESUMO

A new series of unsymmetrical phenyl tellurides derived from 2-N-(quinolin-8-yl) benzamide ligand has been synthesized in a practical manner by the copper-catalyzed method by using diaryl ditelluride and Mg as a reductant at room temperature. In order to augment the Lewis acidity of these newly formed unsymmetrical monotellurides, these have been transformed into corresponding unsymmetrical 2-N-(quinolin-8-yl)benzamide tellurium cations. Subsequently, these Lewis acidic tellurium cations were used as chalcogen bonding catalysts, enabling the synthesis of various substituted 1,2-dihydroquinolines by activating ketones with anilines under mild conditions. Moreover, the synthesized 2-N-(quinolin-8-yl)benzamide phenyl tellurium cation has also catalyzed the formation of ß-amino alcohols in high regioselectivity by effectively activating epoxides at room temperature. Mechanistic insight by 1 H and 19 F NMR study, electrostatic surface potential (ESP map), control reaction in which tellurium cation reacted explosively with epoxide, suggested that the enhanced Lewis acidity of tellurium center seems responsible for efficient catalytic activities under mild conditions enabling ß-amino alcohols with excellent regioselectivity and 1,2-dihydroquinolines with trifluoromethyl, nitro, and pyridylsubstitution, which were difficult to access.

2.
FASEB J ; 36(5): e22274, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35416331

RESUMO

Phosphatidylserine (PS) is a minor phospholipid constituent of high-density lipoprotein (HDL) that exhibits potent anti-inflammatory activity. It remains indeterminate whether PS incorporation can enhance anti-inflammatory effects of reconstituted HDL (rHDL). Human macrophages were treated with rHDL containing phosphatidylcholine alone (PC-rHDL) or PC and PS (PC/PS-rHDL). Interleukin (IL)-6 secretion and expression was more strongly inhibited by PC/PS-rHDL than PC-rHDL in both tumor necrosis factor (TNF)-α- and lipopolysaccharide (LPS)-stimulated macrophages. siRNA experiments revealed that the enhanced anti-inflammatory effects of PC/PS-rHDL required scavenger receptor class B type I (SR-BI). Furthermore, PC/PS-rHDL induced a greater increase in Akt1/2/3 phosphorylation than PC-rHDL. In addition, PC/PS but not PC-rHDL decreased the abundance of plasma membrane lipid rafts and p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation. Finally, when these rHDL formulations were administered to dyslipidemic low-density lipoprotein (LDL)-receptor knockout mice fed a high-cholesterol diet, circulating IL-6 levels were significantly reduced only in PC/PS-rHDL-treated mice. In parallel, enhanced Akt1/2/3 phosphorylation by PC/PS-rHDL was observed in the mouse aortic tissue using immunohistochemistry. We concluded that the incorporation of PS into rHDLs enhanced their anti-inflammatory activity by modulating Akt1/2/3- and p38 MAPK-mediated signaling through SR-BI in stimulated macrophages. These data identify PS as a potent anti-inflammatory component capable of enhancing therapeutic potential of rHDL-based therapy.


Assuntos
Lipoproteínas HDL , Fosfatidilserinas , Animais , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Espaço Intracelular/metabolismo , Lipoproteínas HDL/metabolismo , Macrófagos/metabolismo , Camundongos , Fosfatidilserinas/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
3.
J Emerg Med ; 64(2): 217-219, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36739174

RESUMO

BACKGROUND: Vitamin B12, or cobalamin, is a nutrient that is vital for metabolic function. Absorption of ingested B12 is dependent on intrinsic factor, which is secreted by parietal cells within the stomach. Pernicious anemia is caused by an intrinsic factor deficiency or autoantibodies against intrinsic factor. The presence of parietal cell antibodies can destroy parietal cells, which can also lead to a deficiency in intrinsic factor. Both lead to megaloblastic anemia caused by vitamin B12 deficiency. The typical presentation of pernicious anemia includes fatigue, pale appearance, tingling sensation, depression, alterations to vision and smell, urinary incontinence, psychotic episodes, and weakness. The most effective treatment for pernicious anemia is intramuscular B12. CASE REPORT: A 27-year-old woman with a history of vitiligo presented to the emergency department (ED) with bilateral lower extremity weakness, clumsiness, numbness, and tingling. Physical examination revealed ataxia, no sensation below her umbilicus, decreased strength, and hyperreflexia in both lower extremities. Complete blood count in the ED revealed low hemoglobin and hematocrit and elevated mean corpuscular volume, concerning for pernicious anemia. Further laboratory testing upon inpatient admission revealed a low vitamin B12 level and parietal cell antibodies in the blood. The patient's pernicious anemia was treated with intramuscular vitamin B12 injections, which led to near complete resolution of her symptoms. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Early suspicion and detection of pernicious anemia in the ED can prevent serious and permanent hematologic and neurologic damage and the development of other autoimmune disorders.


Assuntos
Anemia Perniciosa , Deficiência de Vitamina B 12 , Feminino , Humanos , Adulto , Anemia Perniciosa/diagnóstico , Anemia Perniciosa/etiologia , Fator Intrínseco , Vitamina B 12 , Ataxia , Parestesia , Autoanticorpos
5.
FASEB J ; 30(6): 2324-35, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26965683

RESUMO

Activation of inflammatory signaling pathways links obesity with metabolic disorders. TLR4-mediated activation of MAPKs and NF-κB are 2 such pathways implicated in obesity-induced inflammation. Apolipoprotein A-I (apoA-I) exerts anti-inflammatory effects on adipocytes by effluxing cholesterol from the cells via the ATP binding cassette transporter A1 (ABCA1). It is not known if these effects involve inhibition of inflammatory signaling pathways by apoA-I. This study asks if apoA-I inhibits activation of MAPKs and NF-κB in mouse 3T3-L1 adipocytes and whether this inhibition is ABCA1 dependent. Incubation of differentiated 3T3-L1 adipocytes with apoA-I decreased cell surface expression of TLR4 by 16 ± 2% and synthesis of the TLR4 adaptor protein, myeloid differentiation primary response 88, by 24 ± 4% in an ABCA1-dependent manner. ApoA-I also inhibited downstream activation of MAPKs, such as ERK, p38MAPK, and JNK, as well as expression of proinflammatory adipokines in bacterial LPS-stimulated 3T3-L1 adipocytes in an ABCA1-dependent manner. ApoA-I, by contrast, suppressed nuclear localization of the p65 subunit of NF-κB by 30 ± 3% in LPS-stimulated 3T3-L1 adipocytes in an ABCA1-independent manner. In conclusion, apoA-I inhibits TLR4-mediated inflammatory signaling pathways in adipocytes by preventing MAPK and NF-κB activation.-Sultana, A., Cochran, B. J., Tabet, F., Patel, M., Cuesta Torres, L., Barter, P. J., Rye, K.-A. Inhibition of inflammatory signaling pathways in 3T3-L1 adipocytes by apolipoprotein A-I.


Assuntos
Adipócitos/metabolismo , Apolipoproteína A-I/farmacologia , Inflamação/metabolismo , Transdução de Sinais/fisiologia , Células 3T3-L1 , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Adipócitos/efeitos dos fármacos , Animais , Apolipoproteína A-I/administração & dosagem , Apolipoproteína A-I/metabolismo , Sobrevivência Celular , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Relação Dose-Resposta a Droga , Interleucina-6/genética , Interleucina-6/metabolismo , Lipopolissacarídeos/toxicidade , Camundongos , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo
6.
Cureus ; 14(11): e31166, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36483887

RESUMO

We present a case of an 83-year-old female who underwent carpal tunnel release with intravenous regional anesthesia (Bier block) and monitored anesthesia care (MAC). After surgery, the patient developed an abnormal motion of her upper extremity, which was treated as an acute dystonic reaction. Dystonic reactions can occasionally be seen as a post-anesthetic complication, but they are most often associated with antidopaminergic medications. Limbs are rarely affected by dystonic reactions, as they usually affect the head and neck. Acute dystonic reactions can be easily treated with diphenhydramine or benzodiazepines to prevent other extrapyramidal symptoms from occurring. The differential, in this case, was widely varied and inappropriate treatment would have been detrimental to patient care.

7.
Cureus ; 14(11): e31027, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36475228

RESUMO

INTRODUCTION: The electronic medical record (EMR) is often used as the primary source for patient medication lists and history. We sought to determine the accuracy of the EMR in documenting opioid prescriptions in patients undergoing fracture repair compared to a statewide database. METHODS: This retrospective study was conducted at an urban level 1 trauma center. Patients > 18 years old were included if they were admitted directly through the emergency room with isolated single orthopedic injuries. Opioid use and prescription data prior to admission and three months following surgery were collected through the EMR and a California statewide database of controlled substance prescriptions. A 2 x 2 McNemar's test was used to identify discordance between the EMR and Controlled Substance Utilization Review and Evaluation System (CURES). RESULTS: A total of 369 patients were included. The EMR reported that 143 patients had an opioid prescription within 30 days prior to admission compared to 75 patients reported by CURES (discordance rate [DR]: 34.7%) (p < 0.001). Between postoperative days (POD) 0-30, the EMR reported that 367 patients had an opioid prescription compared to 285 reported by CURES (DR: 22.8%) (p < 0.001). Between POD 30-60, the EMR reported that 142 patients had an opioid prescription compared to 84 reported by CURES (DR: 34.7%) (p < 0.001). Between POD 60-90, the EMR reported that 83 patients had an active opioid prescription compared to 60 patients reported by CURES (DR: 41.0%) (p = 0.10). CONCLUSION: There is a significant discordance between the databases in documenting opioid use. Physicians should check multiple sources to best assess active opioid prescriptions.

8.
J Pharm Bioallied Sci ; 13(Suppl 1): S421-S424, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34447124

RESUMO

BACKGROUND: This study aimed to assess the effectiveness of mandibular ramus in gender identification in Haryana population. MATERIALS AND METHODS: One hundred patients were assessed. Panoramic radiological examination was done. Following parameters were recorded: MAX. RM. WDTH (Maximum ramus breadth), MIN. RM. WDTH (Minimum ramus breadth), CND. HGT. RM (Condylar height), PRJ. HGT. RM (Projective height of the ramus), and CRND. HGT. RM (Coronoid height). All the results were recorded in Microsoft excel sheet and were analyzed by SPSS software version 16.0. RESULTS: There is significant difference found in males and females in maximum ramus width, minimum ramus width, condylar height, and coronoid height and between male and females in condylar height and coronoid height. Furthermore, there was statistical significant difference between male and females in coronoid height. CONCLUSION: Mandibular ramus can be used for gender assessment as a part of forensic investigation.

9.
Front Microbiol ; 12: 650771, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936008

RESUMO

The development of salinity affects 7% of the world's land surface, acting as a major constraint to crop productivity. This study attempted to use the co-evolving endophytes of peanut to alleviate salinity stress and enhance the yield of peanut. Diverse and different tissue colonizing endophytes were isolated from peanut and screened in vitro by seed germination bioassay imposing gradients of salinity, with two cultivars TG37A (susceptible) and GG2 (moderately resistant), in potted conditions using saline irrigation water. Finally, nine endophytes capable of producing IAA and ACC-deaminase, promoting root growth and yield in potted conditions were selected for further evaluation in field conditions. They were evaluated with saline water (1.5-2.0 dS/m) in saline soil with susceptible cultivar TG37A. Simultaneously, three endophytes (Bacillus firmus J22N; Bacillus tequilensis SEN15N; and Bacillus sp. REN51N) were evaluated with two cultivars, GG2 and TG37A, during rainy and post-rainy seasons with elevated salinity. The application of endophytes like Bacillus firmus J22N and Bacillus sp. REN51N enhanced the pod and haulm yield of peanuts by 14-19% across cultivars, salinity, and seasons. In addition, there was significant modulation in parameters like relative water content; production of enzymes like superoxide dismutase (SOD), glutathione reductase (GR), catalase (CAT), ascorbate peroxidase (APX), lipid peroxidase (POD), and H2O2 content in leaf; and uptake of potassium. The activities of the enzymes involved in scavenging reactive oxygen species (ROS) increased with salinity, and further increased with endophytes like Bacillus firmus J22N, Bacillus tequilensis SEN15N, and Bacillus sp. REN51N. There was an enhanced accumulation of proline, reduced level of phenol and H2O2, and enhanced uptake of potassium with the inoculation of endophytes. This improved scavenging capacity of plants by endophytic modulation of ROS scavengers, uptake of K, production of ACC deaminase and IAA, root and biomass growth, modulation in relative water content, and enhanced accumulation of osmoprotectant might be the reasons of alleviation of salinity stress. Endophytes could have alleviated salinity stress in peanuts, indicating the mechanisms and potential of peanuts at the field level. These endophytes could be applied to bring agricultural sustainability to salinity-affected areas in the future. Furthermore, few genera viz. Kocuria, Brevundimonas, Agrococcus, Dietzia, and Kytococcus were observed in peanut tissue for the first time.

10.
Neuron ; 107(3): 454-469.e6, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32574560

RESUMO

Neuroscience relies on techniques for imaging the structure and dynamics of neural circuits, but the cell bodies of individual neurons are often obscured by overlapping fluorescence from axons and dendrites in surrounding neuropil. Here, we describe two strategies for using the ribosome to restrict the expression of fluorescent proteins to the neuronal soma. We show first that a ribosome-tethered nanobody can be used to trap GFP in the cell body, thereby enabling direct visualization of previously undetectable GFP fluorescence. We then design a ribosome-tethered GCaMP for imaging calcium dynamics. We show that this reporter faithfully tracks somatic calcium dynamics in the mouse brain while eliminating cross-talk between neurons caused by contaminating neuropil. In worms, this reporter enables whole-brain imaging with faster kinetics and brighter fluorescence than commonly used nuclear GCaMPs. These two approaches provide a general way to enhance the specificity of imaging in neurobiology.


Assuntos
Encéfalo/diagnóstico por imagem , Cálcio/metabolismo , Corpo Celular/patologia , Neurônios/patologia , Imagem Óptica/métodos , Ribossomos/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Caenorhabditis elegans , Proteínas de Ligação ao Cálcio , Corpo Celular/metabolismo , Proteínas de Fluorescência Verde , Camundongos , Neurônios/metabolismo , Neurópilo , Proteína Ribossômica L10/metabolismo , Anticorpos de Domínio Único
11.
Atherosclerosis ; 286: 20-29, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31096070

RESUMO

BACKGROUND AND AIMS: We recently showed that miR-223-3p on high-density lipoproteins (HDL) is exported to endothelial cells, where it inhibits inflammation. However, the origin of miR-223-3p on HDL is unknown. We hypothesize that HDL-associated miR-223-3p originates in myeloid cells and is exported to HDL in a scavenger receptor BI (SR-BI)-dependent manner. METHODS: Polymorphonuclear neutrophils (PMNs) and human monocyte derived macrophages (HMDMs) were incubated with native HDL (nHDL) or discoidal reconstituted HDL (rHDL). Total RNA was isolated before and after incubation. Mature and primary miR-223-3p (pri-mir-223-3p) levels were quantified by real-time PCR. RESULTS: Incubation with nHDL and rHDL increased miR-223-3p export from PMNs and HMDMs. In PMNs, nHDL but not rHDL, increased mature and pri-mir-223-3p. Incubation with HDL also increased Dicer mRNA, a critical regulator of miRNA biogenesis. Incubation of HMDMs with nHDL did not increase cellular levels of mature miR-223-3p, but significantly increased pri-mir-223 levels. Incubation with rHDL had no effect on either mature or pri-mir-223-3p levels. Activated PMNs increased miR-223-3p export to HDL and the production of reactive oxygen species and activated protein kinase C. Blocking HDL binding to SR-BI increased miR-223-3p export to HDL in both PMNs and HMDMs, but did not affect mature and primary miR-223-3p levels. Chemical inhibition of cholesterol flux by Block Lipid Transport (BLT)-1 inhibited HDL-induced pri-mir-223 expression in PMNs. CONCLUSIONS: HDL-associated miR-223-3p originates in PMNs and macrophages. HDL stimulates miR-223-3p biogenesis in PMNs in a process that is regulated by SR-BI-mediated lipid flux.


Assuntos
Lipoproteínas HDL/fisiologia , MicroRNAs/fisiologia , Células Mieloides/fisiologia , Receptores Depuradores Classe B/fisiologia , Células Cultivadas , Humanos , Metabolismo dos Lipídeos/fisiologia , Macrófagos , Neutrófilos
12.
Neuron ; 98(1): 109-126.e8, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29576390

RESUMO

Screens for genes that orchestrate neural circuit formation in mammals have been hindered by practical constraints of germline mutagenesis. To overcome these limitations, we combined RNA-seq with somatic CRISPR mutagenesis to study synapse development in the mouse retina. Here synapses occur between cellular layers, forming two multilayered neuropils. The outer neuropil, the outer plexiform layer (OPL), contains synapses made by rod and cone photoreceptor axons on rod and cone bipolar dendrites, respectively. We used RNA-seq to identify selectively expressed genes encoding cell surface and secreted proteins and CRISPR-Cas9 electroporation with cell-specific promoters to assess their roles in OPL development. Among the genes identified in this way are Wnt5a and Wnt5b. They are produced by rod bipolars and activate a non-canonical signaling pathway in rods to regulate early OPL patterning. The approach we use here can be applied to other parts of the brain.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/fisiologia , Mutagênese/fisiologia , Neurópilo/metabolismo , Retina/metabolismo , Análise de Sequência de RNA/métodos , Via de Sinalização Wnt/fisiologia , Animais , Animais Recém-Nascidos , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Neurópilo/química , Coelhos , Retina/química , Retina/crescimento & desenvolvimento
13.
J Comp Neurol ; 525(4): 885-900, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27560718

RESUMO

Descending projections from the thalamus and related structures to the midbrain are evolutionarily highly conserved. However, the basic organization of this auditory thalamotectal pathway has not yet been characterized. The purpose of this study was to obtain a better understanding of the anatomical and neurochemical features of this pathway. Analysis of the distributions of retrogradely labeled cells after focal injections of retrograde tracer into the inferior colliculus (IC) of the mouse revealed that most of the subcortical descending projections originated in the brachium of the IC and the paralaminar portions of the auditory thalamus. In addition, the vast majority of thalamotectal cells were found to be negative for the calcium-binding proteins calbindin, parvalbumin, or calretinin. Using two different strains of GAD-GFP mice, as well as immunostaining for GABA, we found that a subset of neurons in the brachium of the IC is GABAergic, suggesting that part of this descending pathway is inhibitory. Finally, dual retrograde injections into the IC and amygdala plus corpus striatum as well into the IC and auditory cortex did not reveal any double labeling. These data suggest that the thalamocollicular pathway comprises a unique population of thalamic neurons that do not contain typical calcium-binding proteins and do not project to other paralaminar thalamic forebrain targets, and that a previously undescribed descending GABAergic pathway emanates from the brachium of the IC. J. Comp. Neurol. 525:885-900, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Vias Auditivas/citologia , Colículos Inferiores/citologia , Neurônios/citologia , Animais , Feminino , Processamento de Imagem Assistida por Computador , Masculino , Camundongos , Microscopia Confocal
14.
PLoS One ; 11(3): e0151475, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27002321

RESUMO

BACKGROUND: Apolipoprotein A-II (ApoA-II) is down regulated in the sera of pancreatic ductal adenocarcinoma (PDAC) patients, which may be due to increase utilization of high density lipoprotein (HDL) lipid by pancreatic cancer tissue. This study examined the influence of exogenous ApoA-II on lipid uptake and cell growth in pancreatic cancer (PC) both in vitro and in vivo. METHODS: Cryo transmission electron microscopy (TEM) examined ApoA-II's influence on morphology of SMOFLipid emulsion. The influence of ApoA-II on proliferation of cancer cell lines was determined by incubating them with lipid+/-ApoA-II and anti-SR-B1 antibody. Lipid was labeled with the fluorophore, DiD, to trace lipid uptake by cancer cells in vitro by confocal microscopy and in vivo in PDAC patient derived xenograft tumours (PDXT) by fluorescence imaging. Scavenger receptor class B type-1(SR-B1) expression in PDAC cell lines and in PDAC PDXT was measured by western blotting and immunohistochemistry, respectively. RESULTS: ApoA-II spontaneously converted lipid emulsion into very small unilamellar rHDL like vesicles (rHDL/A-II) and enhanced lipid uptake in PANC-1, CFPAC-1 and primary tumour cells as shown by confocal microscopy. SR-B1 expression was 13.2, 10.6, 3.1 and 2.3 fold higher in PANC-1, MIAPaCa-2, CFPAC-1 and BxPC3 cell lines than the normal pancreatic cell line (HPDE6) and 3.7 fold greater in PDAC tissue than in normal pancreas. ApoA-II plus lipid significantly increased the uptake of labeled lipid and promoted cell growth in PANC-1, MIAPaCa-2, CFPAC-1 and BxPC3 cells which was inhibited by anti SR-B1 antibody. Further, ApoA-II increased the uptake of lipid in xenografts by 3.4 fold. CONCLUSION: Our data suggest that ApoA-II enhance targeting potential of lipid in pancreatic cancer which may have imaging and drug delivery potentialities.


Assuntos
Apolipoproteína A-II/metabolismo , Proliferação de Células/fisiologia , Lipídeos/fisiologia , Neoplasias Pancreáticas/metabolismo , Receptores Depuradores Classe B/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Humanos , Lipoproteínas HDL/metabolismo , Células MCF-7
15.
Diabetes ; 65(12): 3610-3620, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27702832

RESUMO

Elevated pancreatic ß-cell cholesterol levels impair insulin secretion and reduce plasma insulin levels. This study establishes that low plasma insulin levels have a detrimental effect on two major insulin target tissues: adipose tissue and skeletal muscle. Mice with increased ß-cell cholesterol levels were generated by conditional deletion of the ATP-binding cassette transporters, ABCA1 and ABCG1, in ß-cells (ß-DKO mice). Insulin secretion was impaired in these mice under basal and high-glucose conditions, and glucose disposal was shifted from skeletal muscle to adipose tissue. The ß-DKO mice also had increased body fat and adipose tissue macrophage content, elevated plasma interleukin-6 and MCP-1 levels, and decreased skeletal muscle mass. They were not, however, insulin resistant. The adipose tissue expansion and reduced skeletal muscle mass, but not the systemic inflammation or increased adipose tissue macrophage content, were reversed when plasma insulin levels were normalized by insulin supplementation. These studies identify a mechanism by which perturbation of ß-cell cholesterol homeostasis and impaired insulin secretion increase adiposity, reduce skeletal muscle mass, and cause systemic inflammation. They further identify ß-cell dysfunction as a potential therapeutic target in people at increased risk of developing type 2 diabetes.


Assuntos
Tecido Adiposo/metabolismo , Colesterol/metabolismo , Células Secretoras de Insulina/metabolismo , Músculo Esquelético/metabolismo , Transportador 1 de Cassete de Ligação de ATP/deficiência , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/deficiência , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Western Blotting , Ácido Graxo Sintases , Glucose/metabolismo , Glicogênio/metabolismo , Homeostase/genética , Homeostase/fisiologia , Insulina/metabolismo , Ácido Láctico/sangue , Imageamento por Ressonância Magnética , Espectrometria de Massas , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase
16.
Sci Rep ; 5: 8741, 2015 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-25737239

RESUMO

Cholesteryl ester transfer protein (CETP) mediates the transfer of cholesterol esters (CE) from atheroprotective high-density lipoproteins (HDL) to atherogenic low-density lipoproteins (LDL). CETP inhibition has been regarded as a promising strategy for increasing HDL levels and subsequently reducing the risk of cardiovascular diseases (CVD). Although the crystal structure of CETP is known, little is known regarding how CETP binds to HDL. Here, we investigated how various HDL-like particles interact with CETP by electron microscopy and molecular dynamics simulations. Results showed that CETP binds to HDL via hydrophobic interactions rather than protein-protein interactions. The HDL surface lipid curvature generates a hydrophobic environment, leading to CETP hydrophobic distal end interaction. This interaction is independent of other HDL components, such as apolipoproteins, cholesteryl esters and triglycerides. Thus, disrupting these hydrophobic interactions could be a new therapeutic strategy for attenuating the interaction of CETP with HDL.


Assuntos
Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Lipoproteínas HDL/metabolismo , Lipídeos de Membrana/metabolismo , Simulação de Dinâmica Molecular , Proteínas de Transferência de Ésteres de Colesterol/genética , Proteínas de Transferência de Ésteres de Colesterol/ultraestrutura , Microscopia Crioeletrônica , Tomografia com Microscopia Eletrônica , Humanos , Interações Hidrofóbicas e Hidrofílicas , Imageamento Tridimensional , Lipoproteínas HDL/sangue , Lipoproteínas HDL/ultraestrutura , Lipossomos/química , Lipossomos/metabolismo , Lipossomos/ultraestrutura , Lipídeos de Membrana/química , Microscopia Eletrônica de Transmissão , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/ultraestrutura
17.
Redox Biol ; 1: 441-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24191238

RESUMO

Neurons rely on the release and subsequent cleavage of GSH to cysteinylglycine (CysGly) by astrocytes in order to maintain optimal intracellular GSH levels. In neurodegenerative diseases characterised by oxidative stress, neurons need an optimal GSH supply to defend themselves against free radicals released from activated microglia and astroglia. The rate of GSH synthesis is controlled largely by the activity of γ-glutamyl cysteine ligase. Expression of γ-glutamyl cysteine ligase and of the Xc- system, which facilitates cystine uptake, is regulated by the redox-sensitive transcription factor, nuclear factor erythroid-2-related factor 2 (Nrf2). Compounds that can activate the Nrf2-ARE pathway, referred to as 'Nrf2 activators' are receiving growing attention due to their potential as GSH-boosting drugs. This study compares four known Nrf2 activators, R-α-Lipoic acid (LA), tert-butylhydroquinone (TBHQ), sulforaphane (SFN) and Polygonum cuspidatum extract containing 50% resveratrol (PC-Res) for their effects on astroglial release of GSH and CysGly. GSH levels increased dose-dependently in response to all four drugs. Sulforaphane produced the most potent effect, increasing GSH by up to 2.4-fold. PC-Res increased GSH up to 1.6-fold, followed by TBHQ (1.5-fold) and LA (1.4-fold). GSH is processed by the ectoenzyme, γ-glutamyl transpeptidase, to form CysGly. Once again, SFN produced the most potent effect, increasing CysGly by up to 1.7-fold, compared to control cells. TBHQ and PC-Res both induced fold increases of 1.3, followed by LA with a fold increase of 1.2. The results from the present study showed that sulforaphane, followed by lipoic acid, resveratrol and Polygonum multiflorum were all identified as potent "GSH and Cys-Gly boosters".


Assuntos
Astrócitos/efeitos dos fármacos , Dipeptídeos/metabolismo , Glutationa/metabolismo , Homocisteína/metabolismo , Hidroquinonas/farmacologia , Isotiocianatos/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Estilbenos/farmacologia , Astrócitos/citologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Extratos Vegetais/farmacologia , Resveratrol , Sulfóxidos , Ácido Tióctico/farmacologia
18.
J Clin Med ; 2(4): 260-3, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-26237147

RESUMO

An 87-year old Caucasian male with past medical history of rheumatoid arthritis (RA) and chronic kidney disease presents with left hand erythema, pain, tenderness, induration and edema. Clinically, these hand findings began proximal to the metacarpo-phalangeal joints and extended to the distal wrist. He was noted to have ipsilateral axillary lymph node enlargement but denied any constitutional signs or symptoms. Laboratory markers of inflammation were poor prognostic indicators due to relatively active RA, the use of chronic daily glucocorticoids and weekly adalimumab use. Oral antibiotics were administered with limited success leading to a skin biopsy which reported a hematogenously disseminated fungal panniculitis; cultures grew Cryptococcus neoformans, however, serum cryptococcal antigen was negative. With initial fluconazole treatment, skin findings and lymphadenopathy improved gradually over the next six months. However, the patient's improvement stagnated and his condition reverted back to the state of initial presentation.

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