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1.
Mol Cell ; 68(3): 528-539.e5, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29100053

RESUMO

Nascent polypeptides can modulate the polypeptide elongation speed on the ribosome. Here, we show that nascent chains can even destabilize the translating Escherichia coli ribosome from within. This phenomenon, termed intrinsic ribosome destabilization (IRD), occurs in response to a special amino acid sequence of the nascent chain, without involving the release or the recycling factors. Typically, a consecutive array of acidic residues and those intermitted by alternating prolines induce IRD. The ribosomal protein bL31, which bridges the two subunits, counteracts IRD, such that only strong destabilizing sequences abort translation in living cells. We found that MgtL, the leader peptide of a Mg2+ transporter (MgtA), contains a translation-aborting sequence, which sensitizes the ribosome to a decline in Mg2+ concentration and thereby triggers the MgtA-upregulating genetic scheme. Translation proceeds at an inherent risk of ribosomal destabilization, and nascent chain-ribosome complexes can function as a Mg2+ sensor by harnessing IRD.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Biossíntese de Proteínas , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Adenosina Trifosfatases/química , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Escherichia coli/química , Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Magnésio/metabolismo , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Mutação , Conformação Proteica , Estabilidade Proteica , Aminoacil-RNA de Transferência/química , Aminoacil-RNA de Transferência/genética , Aminoacil-RNA de Transferência/metabolismo , Proteínas Ribossômicas/química , Proteínas Ribossômicas/genética , Ribossomos/química , Ribossomos/genética , Relação Estrutura-Atividade
2.
Cell Mol Life Sci ; 81(1): 32, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214780

RESUMO

BACKGROUND: Dysbiosis of gut microbiota is frequent in liver cirrhosis (LC) patients, and splenectomy (SP) has been reported to improve LC. Herein, we report the effects of SP on gut microbiota, especially on Veillonella parvula, a Gram-negative coccus of the gastrointestinal tract, in LC mice, and the underlying mechanism. METHODS: LC mice models were induced by tail vein injection of concanavalin A (ConA), followed by SP. 16 s rRNA sequencing was conducted to analyze the effects of ConA induction and SP on mouse gut microbiota and the gene expression affected by gut microbiota. LC mice receiving SP were gavaged with Veillonella parvula. Likewise, hepatic stellate cells (HSC) and hepatocytes (HC) were induced with conditioned medium (CM) of Veillonella parvula. RESULTS: SP alleviated LC in mice by restoring gut barrier function and maintaining gut microbiota balance, with Veillonella as the key genus. The Veillonella parvula gavage on LC mice reversed the ameliorative effect of SP. The CM of Veillonella parvula promoted the activation of HSC and the release of IL-6, IL-1ß, and TNF-α. Also, the CM of Veillonella parvula induced HC pyroptosis and the release of ALT and AST. Veillonella parvula represented an imbalance in the gut microbiota, thus enhancing gut-derived endotoxins in the liver with the main target being Tlr4/Nlrp3. Inhibition of Tlr4 blocked Veillonella parvula-induced HC damage, HSC activation, and subsequent LC progression. CONCLUSION: SP-mediated gut microbiota regulation ameliorates ConA-related LC progression by inhibiting Tlr4/Nlrp3 in the liver.


Assuntos
Microbioma Gastrointestinal , Veillonella , Humanos , Animais , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Esplenectomia , Receptor 4 Toll-Like/metabolismo , Cirrose Hepática/terapia
3.
Nano Lett ; 24(34): 10674-10680, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39141815

RESUMO

The successful synthesis of borophene beyond the monolayer limit has expanded the family of two-dimensional boron nanomaterials. While atomic-resolution topographic imaging has been previously reported, vibrational mapping has the potential to reveal deeper insight into the chemical bonding and electronic properties of bilayer borophene. Herein, inelastic electron tunneling spectroscopy (IETS) is used to resolve the low-energy vibrational and electronic properties of bilayer-α (BL-α) borophene on Ag(111) at the atomic scale. Using a carbon monoxide (CO)-functionalized scanning tunneling microscopy tip, the BL-α borophene IETS spectra reveal unique features compared to single-layer borophene and typical CO vibrations on metal surfaces. Distinct vibrational spectra are further observed for hollow and filled boron hexagons within the BL-α borophene unit cell, providing evidence for interlayer bonding between the constituent borophene layers. These experimental results are compared with density functional theory calculations to elucidate the interplay between the vibrational modes and electronic states in bilayer borophene.

4.
J Physiol ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39365978

RESUMO

A significant fraction of the popular inbred C57Bl/6J mice show structural and biochemical features of the congenital portosystemic shunt (PSS). How this hepatic abnormality affects physiological and behavioural parameters has not been explored in detail. Here, we confirmed the frequent occurrence of the PSS in C57Bl/6J mice by three different methods. We screened a cohort of 119 C57Bl/6J mice for total bile acids (TBA) in plasma, identified 11 animals (9.2%) with high TBA (>11 µm; 171.1 ± 76.8 µm), and confirmed PSS presence in that subset by magnetic resonance angiography and 1H-magnetic resonance spectroscopy of brain metabolites in the hippocampal area. In addition to the high glutamine and low myo-inositol levels, we detected lower levels of several neurotransmitters and metabolites in the hippocampus, higher brain weight and volume, as well as enhanced brain glucose utilisation in the PSS mice. We also observed differences in peripheral organ weights, haematological cell counts and clinical chemistry parameters in C57Bl/6J mice with and without PSS. Animals with PSS were slightly hyperlocomotive, had better balance on the rotarod, showed altered gait properties, and displayed attenuated fear memory in the fear conditioning test. Furthermore, we revealed a significant alteration of the pharmacokinetic profile of diazepam in C57Bl/6J mice with PSS. Our data support previous reports of hepatic disturbances and demonstrate an altered neurobiological phenotype in C57Bl/6J mice with PSS. Such congenital differences between inbred C57Bl/6J littermates may significantly distort experimental outcomes of pharmacological, behavioural and genetic studies. KEY POINTS: A significant proportion of C57Bl/6J mice, an inbred strain popular in preclinical research, have congenital portosystemic shunts (PSS) that allow venous blood to enter systemic circulation bypassing the liver. In this study, we extended existing knowledge of PSS consequences, particularly with respect to the effects on brain structure and function. We demonstrated that C57Bl/6J mice with PSS differ from their normal counterparts in brain size and contents of several neuroactive substances, as well as in peripheral organ weights, rate of glucose utilisation, blood cell counts and blood clinical chemistry parameters. C57Bl/6J mice with PSS showed altered locomotor behaviour, performed worse in a memory test and had abnormal blood pharmacokinetics of a benzodiazepine drug after a single administration. PSS presence may significantly complicate the interpretation of experiments in C57Bl/6J mice; therefore, we propose that before their use in biomedical studies, these mice should be screened with a simple blood test.

5.
J Neurophysiol ; 132(1): 177-183, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38836296

RESUMO

The reliable induction of long-term potentiation (LTP) in the dentate gyrus (DG) in vitro requires the blockade of the γ-aminobutyric acid A (GABAA) receptor. In these studies we examined the effectiveness of the specific GABAA receptor antagonist bicuculline methiodide (BMI) in facilitating LTP in the DG from hippocampal slices obtained from either C57Bl/6 mice or Sprague-Dawley rats, two species commonly used for electrophysiology. In the C57Bl/6 mice, maximal short-term potentiation and LTP in the DG were produced with a concentration of 5 µM BMI. In contrast, a concentration of 10 µM BMI was required to produce maximal short-term potentiation and LTP in the DG of Sprague-Dawley rats. These results reveal that there are species differences in the optimal amount of BMI required to produce robust and reliable LTP in the rodent DG in vitro and highlight the need to take consideration of the species being used when choosing concentrations of pharmacological agents to employ for electrophysiological use.NEW & NOTEWORTHY In this report we provide specific neurophysiological evidence for concentrations of GABAA antagonist required to study long-term potentiation in the medial perforant pathway of the dentate gyrus. Two commonly used species, Sprague-Dawley rats and C57Bl/6 mice, require different concentrations of bicuculline methiodide to induce optimal short-term and long-term potentiation.


Assuntos
Bicuculina , Giro Denteado , Antagonistas de Receptores de GABA-A , Potenciação de Longa Duração , Camundongos Endogâmicos C57BL , Ratos Sprague-Dawley , Animais , Potenciação de Longa Duração/efeitos dos fármacos , Potenciação de Longa Duração/fisiologia , Giro Denteado/efeitos dos fármacos , Giro Denteado/fisiologia , Bicuculina/farmacologia , Bicuculina/análogos & derivados , Antagonistas de Receptores de GABA-A/farmacologia , Camundongos , Ratos , Masculino , Receptores de GABA-A/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Receptores de GABA-A/fisiologia , Especificidade da Espécie
6.
Int J Cancer ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38975879

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) remains the most lethal cancer type. PDAC is characterized by fibrotic, hypoxic, and presumably acidic tumor microenvironment (TME). Acidic TME is an important player in tumor development, progression, aggressiveness, and chemoresistance. The dysregulation of ductal ion transporters/channels might contribute to extracellular pH (pHe) acidification and PDAC progression. Our aim was to test whether H+/K+-ATPases and pH-sensitive K+ channels contribute to these processes and could be targeted by clinically approved drugs. We used human pancreatic cancer cells adapted to various pHe conditions and grown in monolayers and spheroids. First, we created cells expressing pHoran4 at the outer plasma membrane and showed that pantoprazole, the H+/K+-ATPase inhibitor, alkalinized pHe. Second, we used FluoVolt to monitor the membrane voltage (Vm) and showed that riluzole hyperpolarized Vm, most likely by opening of pH-sensitive K+ channels such as TREK-1. Third, we show that pantoprazole and riluzole inhibited cell proliferation and viability of monolayers and spheroids of cancer cells adapted to various pHe conditions. Most importantly, combination of the two drugs had significantly larger inhibitory effects on PDAC cell survival. We propose that co-targeting H+/K+-ATPases and pH-sensitive K+ channels by re-purposing of pantoprazole and riluzole could provide novel acidosis-targeted therapies of PDAC.

7.
BMC Plant Biol ; 24(1): 683, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39020306

RESUMO

Campanumoea javanica Bl. (CJ) traditionally used in Southwestern China, is now widely consumed as a health food across the nation. Due to its similar efficacy to Codonopsis Radix (CR) and their shared botanical family, CJ is often used as a substitute for CR. According to the Chinese Pharmacopoeia, Codonopsis pilosula var. modesta (Nannf.) L.T. Shen (CPM), Codonopsis pilosula (Franch.) Nannf. (CP), and Codonopsis tangshen Oliv. (CT) are the primary sources of CR. However, details on the differences in composition, effectiveness, and compositional between CJ and CR are still limited. Besides, there is little evidence to support the application of CJ as a drug. In this study, we employed widely targeted metabolomics, network pharmacology analysis, and molecular docking to explore the disparities in metabolite profiles between CJ and CR and to predict the pharmacological mechanisms of the dominant differential metabolites of CJ and their potential medicinal applications. The widely targeted metabolomics results indicated that 1,076, 1,102, 1,102, and 1,093 compounds, most phenolic acids, lipids, amino acids, and flavonoids, were characterized in CJ, CPM, CP, and CT, respectively. There were an average of 1061 shared compounds in CJ and CRs, with 95.07% similarity in metabolic profiles. Most of the metabolites in CJ were previously unreported. Twelve of the seventeen dominant metabolites found in CJ were directly associated with treating cancer and lactation, similar to the traditional medicinal efficacy. The molecular docking results showed that the dominant metabolites of CJ had good docking activity with the core targets PIK3R1, PIK3CA, ESR1, HSP90AA1, EGFR, and AKT1. This study provides a scientific basis for understanding the similarities and differences between CJ and CR at the metabolome level, offering a theoretical foundation for developing innovative medications from CJ. Additionally, it significantly enhances the metabolite databases for both CJ and CR.


Assuntos
Codonopsis , Metabolômica , Farmacologia em Rede , Codonopsis/química , Codonopsis/metabolismo , Simulação de Acoplamento Molecular , Medicamentos de Ervas Chinesas/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Raízes de Plantas/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Extratos Vegetais/metabolismo
8.
J Virol ; 97(5): e0165822, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37071015

RESUMO

Japanese encephalitis virus (JEV), with neurotoxic and neuroinvasive properties, is the major cause of human viral encephalitis in Asia. Although Guillain-Barré syndrome caused by JEV infections is not frequent, a few cases have been reported in recent years. To date, no existing animal model for JEV-induced peripheral nerve injury (PNI) has been established, and thus the pathogenic mechanism is not clarified. Therefore, an animal model is urgently required to clarify the correlation between JEV infection and PNI. In the present study, we used JEV GIb strain of NX1889 to establish a mouse model of JEV infection. The general neurological signs emerged on day 3 of modeling. The motor function continued to deteriorate, reaching a maximum at 8 to 13 days postinfection (dpi) and gradually recovered after 16 dpi. The injuries of 105 PFU and 106 PFU groups were the most severe. Transmission electron microscopy and immunofluorescence staining showed varying degrees of demyelination and axonal degeneration in the sciatic nerves. The electrophysiological recordings demonstrated the presence of demyelinating peripheral neuropathy with reduced nerve conduction velocity. The decreased amplitudes and the prolonged end latency revealed axonal-type motor neuropathy. Demyelination is predominant in the early stage, followed by axonal injury. The expression level of JEV-E protein and viral RNA was elevated in the injured sciatic nerves, suggesting that it may cause PNI at the early stage. Inflammatory cell infiltration and increased inflammatory cytokines indicated that neuroinflammation is involved in JEV-induced PNI. IMPORTANCE JEV is a neurotropic flavivirus belonging to the Flaviviridae family and causes high mortality and disability rates. It invades the central nervous system and induces acute inflammatory injury and neuronal death. Thus, JEV infection is a major global public health concern. Previously, motor dysfunction was mainly attributed to central nervous system damage. Our knowledge regarding JEV-induced PNI is vague and neglected. Therefore, a laboratory animal model is essential. Herein, we showed that C57BL/6 mice can be used to study JEV-induced PNI through multiple approaches. We also demonstrated that viral loads might be positively correlated with lesion severity. Therefore, inflammation and direct virus infection may be the putative mechanisms underlying JEV-induced PNI. The results of this study laid the foundation for further elucidation of the pathogenesis mechanisms of PNI caused by JEV.


Assuntos
Modelos Animais de Doenças , Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Traumatismos dos Nervos Periféricos , Animais , Humanos , Camundongos , Doenças Desmielinizantes , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Camundongos Endogâmicos C57BL
9.
Cell Tissue Res ; 395(1): 81-103, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38032480

RESUMO

Endothelial cells of mammalian blood vessels have multiple levels of heterogeneity along the vascular tree and among different organs. Further heterogeneity results from blood flow turbulence and variations in shear stress. In the aorta, vascular endothelial protein tyrosine phosphatase (VE-PTP), which dephosphorylates tyrosine kinase receptor Tie2 in the plasma membrane, undergoes downstream polarization and endocytosis in endothelial cells exposed to laminar flow and high shear stress. VE-PTP sequestration promotes Tie2 phosphorylation at tyrosine992 and endothelial barrier tightening. The present study characterized the heterogeneity of VE-PTP polarization, Tie2-pY992 and total Tie2, and claudin-5 in anatomically defined regions of endothelial cells in the mouse descending thoracic aorta, where laminar flow is variable and IgG extravasation is patchy. We discovered that VE-PTP and Tie2-pY992 had mosaic patterns, unlike the uniform distribution of total Tie2. Claudin-5 at tight junctions also had a mosaic pattern, whereas VE-cadherin at adherens junctions bordered all endothelial cells. Importantly, the amounts of Tie2-pY992 and claudin-5 in aortic endothelial cells correlated with downstream polarization of VE-PTP. VE-PTP and Tie2-pY992 also had mosaic patterns in the vena cava, but claudin-5 was nearly absent and extravasated IgG was ubiquitous. Correlation of Tie2-pY992 and claudin-5 with VE-PTP polarization supports their collective interaction in the regulation of endothelial barrier function in the aorta, yet differences between the aorta and vena cava indicate additional flow-related determinants of permeability. Together, the results highlight new levels of endothelial cell functional mosaicism in the aorta and vena cava, where blood flow dynamics are well known to be heterogeneous.


Assuntos
Células Endoteliais , Proteínas Tirosina Fosfatases , Animais , Camundongos , Aorta , Caderinas/metabolismo , Permeabilidade Capilar , Claudina-5/metabolismo , Células Endoteliais/metabolismo , Imunoglobulina G , Mamíferos/metabolismo , Permeabilidade , Proteínas Tirosina Fosfatases/metabolismo
10.
New Phytol ; 241(2): 607-622, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37897058

RESUMO

The fine centromere structure in Robertsonian wheat-rye translocation chromosomes exhibits variation among different translocation genotypes. Within extensively employed wheat-rye 1RS.1BL translocation lines in wheat breeding, their translocated chromosomes frequently display fused centromere. Nevertheless, the mechanism governing the functionality of the fused centromere in 1RS.1BL translocated chromosomes remains to be clarified. In this study, we investigated the fine centromere structure of the 1RS.1BL translocated chromosome through a combination of cytological and genomics methods. We found that only the rye-derived centromere exhibits functional activity, whether in breeding applications or artificially synthesized translocation chromosomes. The active rye-derived centromere had higher proportion of young full-length long terminal repeat retrotransposons (flLTR-RTs) and more stable non-B DNA structures, which may be beneficial toward transcription of centromeric repeats and CENH3 loading to maintain the activity of rye centromeres. High levels of DNA methylation and H3K9me2 were found in the inactive wheat-derived centromeres, suggesting that it may play a crucial role in maintaining the inactive status of the wheat centromere. Our works elucidate the fine structure of 1RS.1BL translocations and the potential mechanism of centromere inactivation in the fused centromere, contributing knowledge to the application of fused centromere in wheat breeding formation of new wheat-rye translocation lines.


Assuntos
Retroelementos , Secale , Retroelementos/genética , Secale/genética , Melhoramento Vegetal , Cromossomos de Plantas/genética , Triticum/genética , Centrômero/genética , Translocação Genética
11.
Cytokine ; 184: 156754, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39299101

RESUMO

IgG4-Related Ophthalmic Disease (IgG4-ROD) is a chronic autoimmune-mediated fibrotic disease that predominantly affects the lacrimal glands, often leading to loss of function in the involved tissues or organs. Recent studies have demonstrated that MMP-12 is highly expressed in IgG4-ROD and plays a significant role in regulating immune responses. In this study, we reviewed nine patients diagnosed with IgG4-ROD based on clinical manifestations and histological analysis, and we investigated the expression of IL-33/ST2 and MMP-12 in IgG4-ROD lacrimal gland tissues using IHC. We found that IL-33 interacts with its specific receptor ST2, both of which are significantly overexpressed in IgG4-ROD tissues. Additionally, we successfully constructed a mouse model by introducing the LatY136F mutation into C57BL/6 mice to mimic IgG4-ROD lacrimal gland involvement, which helped elucidate the mechanisms involved in the induction of MMP-12. Furthermore, immunofluorescence staining confirmed that most MMP-12+ cells were derived from M2 macrophages, and an ELISA assay demonstrated that IL-33 upregulates MMP-12 in IgG4-ROD. Collectively, these data suggest that the IL-33/ST2/MMP-12 signaling pathway is activated in IgG4-ROD, with IL-33/ST2 potentially promoting M2 macrophage polarization and activation to produce MMP-12, which may serve as a novel therapeutic target for IgG4-ROD.

12.
Microb Pathog ; 186: 106506, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38128702

RESUMO

Equid herpesvirus type 8 (EqHV-8) is known to cause abortion, respiratory signs, and viral encephalitis in equines. EqHV-8 has been reported to cause serious economic losses in large-scale donkey farms in China. However, little is known about the viral replication and immune reaction in the brains and lungs of EqHV-8-induced C57BL/6J mice. We determined the pathogenicity and immune status in a mice model. The C57BL/6J mice were infected with the EqHV-8 donkey/Shandong/10/2021 strain, and the clinical signs and body weights were evaluated every day. In addition, viremia, virus loads, and the expression of pro-inflammatory cytokines in mice brains and lungs were assessed at 1, 3, 5, and 7 days post infection (dpi). Our results demonstrated that mice in the EqHV-8 infected group displayed body weight loss, dyspnea signs, and viremia. The expression of interleukin (IL)-1ß, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, IL-6 mRNA was increased in the brains and lungs of EqHV-8-infected mice than that in control group at 5 dpi and 7 dpi, and IL-12a expression was increased at 7 dpi. These data indicated that EqHV-8 elicited a strong cytokines response, caused neurogenic disease and respiratory signs in C57BL/6J mice, thus revealing the pathogenicity of EqHV-8.


Assuntos
Citocinas , Viremia , Animais , Cavalos , Camundongos , Citocinas/metabolismo , Camundongos Endogâmicos C57BL , Virulência , Fator de Necrose Tumoral alfa , Equidae , Interleucina-1beta
13.
J Nutr ; 154(1): 60-68, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37984745

RESUMO

BACKGROUND: Male reproduction is impacted by both over- and under-nutrition, demonstrated by animal studies using high-fat and low-protein dietary interventions. Little is known about the impacts of low-fat, high-carb diets and types of dietary carbohydrates on sperm traits. OBJECTIVES: Using a nutritional geometry approach, we investigated the effects of partially or completely substituting glucose for fructose in isocaloric diets containing either 10%, 20%, or 30% fat (by energy) on sperm traits in mice. METHODS: Male C57BL/6J mice were fed 1 of 15 experimental diets for 18 wk starting from 8 wk of age. Reproductive organs were then harvested, and sperm concentration, motility, and velocity were measured using Computer-Assisted Sperm Analysis. RESULTS: Increasing dietary fat from 10% to 30% while maintaining energy density at 14.3 kJ/g and protein content at 20% resulted in increased body weight and sperm production but reduced the percentage of motile sperm. Body weight and seminal vesicle weight were maximized on diets containing a 50:50 mix of fructose and glucose, but carbohydrate type had few significant impacts on epididymal sperm traits. CONCLUSIONS: The opposing impacts of dietary fat on mouse sperm quantity and quality observed suggest that male fertility may not be optimized by a single diet; rather, context-specific dietary guidelines targeted to specific concerns in semen quality may prove useful in treating male infertility.


Assuntos
Análise do Sêmen , Sêmen , Masculino , Animais , Camundongos , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Camundongos Endogâmicos C57BL , Espermatozoides , Gorduras na Dieta , Dieta com Restrição de Gorduras , Glucose , Aumento de Peso , Frutose , Peso Corporal
14.
J Nutr ; 154(9): 2752-2762, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39053605

RESUMO

BACKGROUND: Obesity and consumption of high-fat diets (HFD) are associated with intestinal permeabilization and increased paracellular transport of endotoxins, which can promote neuroinflammation. Inflammation can affect the hypothalamic pituitary adrenal (HPA) axis, which controls responses to stress and downregulates the brain-derived neurotrophic factor (BDNF), which can promote anxiety and depression, conditions frequently found in obesity. We previously showed that consumption of anthocyanins (AC) mitigate HFD-induced insulin resistance, intestinal permeability, and inflammation. OBJECTIVES: This study investigated if a dietary supplementation with a cyanidin- and delphinidin-rich extract (CDRE) could counteract HFD/obesity-induced hippocampal inflammation in mice. METHODS: C57BL/6J male mice were fed for 14 wk on one of the following diets: 1) a control diet containing 10% total calories from fat (C), 2) a control diet supplemented with 40 mg AC/kg body weight (BW) (CAC), 3) a HFD containing 60% total calories from fat (lard) (HF), or 4) the HFD supplemented with 2, 20, or 40 mg AC/kg BW (HFA2, HFA20, and HFA40, respectively). In plasma and in the hippocampus, parameters of neuroinflammation and the underlying cause (endotoxemia) and consequences (alterations to the HPA and BDNF downregulation) were measured. RESULTS: Consumption of the HFD caused endotoxemia. Accordingly, hippocampal Tlr4 mRNA levels were 110% higher in the HF group, which were both prevented by CDRE supplementation. Consumption of the HFD also caused: 1) microgliosis and increased expression of genes involved in neuroinflammation, that is, Iba-1, Nox4, Tnfα, and Il-1ß, 2) alterations of HPA axis regulation, that is, with low expression of mineralocorticoid (MR) and glucocorticoid (GR) receptors; and 3) decreased Bdnf expression. Supplementation of HFD-fed mice with CDRE mitigated neuroinflammation, microgliosis, and MR and BDNF decreases. CONCLUSIONS: CDRE supplementation mitigates the negative effects associated with HFD consumption and obesity in mouse hippocampus, in part by decreasing inflammation, improving glucocorticoid metabolism, and upregulating BDNF.


Assuntos
Antocianinas , Dieta Hiperlipídica , Hipocampo , Inflamação , Camundongos Endogâmicos C57BL , Animais , Antocianinas/farmacologia , Dieta Hiperlipídica/efeitos adversos , Masculino , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Camundongos , Inflamação/prevenção & controle , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Obesidade , Suplementos Nutricionais
15.
Exp Eye Res ; 246: 110014, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39074653

RESUMO

In this study, we investigated the effects of flickering light on refractive development of mice and the changes of fundus structure and function during this process. C57BL/6 mice were randomly divided into control group and flickering light-induced myopia (FLM) group. Mice in the control group were fed under normal lighting. FLM group mice were fed under lighting with a duty cycle of 50% and flash frequency of 2 Hz. Refractive status, axial length (AL), corneal radius of curvature (CRC), and electroretinogram signals were measured in all animals before treatment and at 2 and 4 weeks after treatment. Retinal thickness (RT), choroidal thickness (ChT) and choroidal blood perfusion (ChBP) were measured by optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). After 4 weeks of flickering light stimulation, the mice became myopia, the AL increased, but the CRC remained constant. The induction of myopia reduced the implicit time and amplitude of a-wave and b-wave in electroretinogram, which affects the function of retina. Full-layer retinal thickness, ChT and ChBP decreased at both 2 and 4 weeks after flickering light induction. The superficial and middle layers of the retina were significantly thinner, while the deep layer was only slightly thinner without statistical significance. Calculated by the concentric circle algorithm, the decrease of choroidal blood perfusion in FLM was mainly concentrated in the concentric circle area with the optic disc as the center radius of 150-450 µm. In conclusion, the present study shows that flickering light can successfully induce myopia in C57BL/6 mice, affect the electrophysiological activity of retina, and cause changes in fundus tissue structure and blood flow.


Assuntos
Modelos Animais de Doenças , Eletrorretinografia , Angiofluoresceinografia , Fundo de Olho , Camundongos Endogâmicos C57BL , Miopia , Refração Ocular , Retina , Tomografia de Coerência Óptica , Animais , Camundongos , Tomografia de Coerência Óptica/métodos , Miopia/fisiopatologia , Miopia/etiologia , Refração Ocular/fisiologia , Retina/fisiopatologia , Angiofluoresceinografia/métodos , Corioide/irrigação sanguínea , Estimulação Luminosa , Luz , Comprimento Axial do Olho , Masculino
16.
Ann Hematol ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225777

RESUMO

T-cell acute lymphoblastic leukemia/lymphoma (T-ALL/LBL) and Burkitt lymphoma (BL) are uncommon, highly aggressive diseases originating either from immature precursor T cells or from mature B cells in BL. We retrospectively analyzed the outcome of an early autologous and/or allogeneic stem cell transplantation (SCT) concept in 28 patients with advanced stage T-ALL/LBL and BL after three to four remission induction/consolidation chemotherapy cycles. Considering only patients in first complete remission (CR), the 5-year overall survival (OS) and event-free survival (EFS) was 91% in patients with BL and 73% in patients with T-ALL/LBL with a 5-year relapse incidence (RI) of 9% in patients with BL and 27% in patients with T-ALL/LBL. All relapsing patients finally succumbed to the disease (n = 10) or complications/toxicity after having received a salvage allogeneic transplant (n = 5). Despite the low patient number our retrospective single-centre analysis by incorporating an early intensive high-dose chemo-/radiotherapy strategy with either autologous or allogeneic stem cell transplantation, although preliminary, show promising long-term outcome. Further studies are highly warranted to better define those patients who might benefit most from such a treatment approach.

17.
World J Urol ; 42(1): 300, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710872

RESUMO

OBJECTIVE: To observe the effect of acupuncture Zhibian (BL54) on the function of the bladder in controlling urine in women under ultrasound. METHOD: 74 healthy subjects were randomly divided into deep acupuncture group of 37 cases and shallow acupuncture group of 37 cases. Under the guidance of ultrasound, the two groups of subjects were acupunctured at bilateral BL54. The deep acupuncture group was acupunctured to the pudendal nerve, and the shallow acupuncture group was acupunctured to the superficial fascia. Ultrasound was used to observe the peak systolic velocity (PSV), time average maximum velocity (TAMX), end diastolic velocity (EDV), pulsation index (PI), resistance index (RI) of the pudendal arteries, and bladder volume of two groups of subjects before and after acupuncture. The anatomical hierarchical structure of bilateral BL54 and score of Chinese version of the Massachusetts General Hospital Acupuncture Sensation Scale (C-MASS) of all subjects was measured. RESULT: After acupuncture, the PSV, TMAX of the pudendal artery, bladder volume, and the Score of C-MASS Scale in the deep acupuncture group were higher than in the shallow acupuncture group (P < 0.05). The RI of the pudendal arteries in the shallow acupuncture group decreased compared to before acupuncture (P < 0.05). CONCLUSION: Acupuncture at the BL54 can increase the blood flow velocity of the pudendal artery, improve the function of the bladder in controlling urine in women, and different depths of acupuncture will have different therapeutic effects.


Assuntos
Terapia por Acupuntura , Bexiga Urinária , Humanos , Feminino , Terapia por Acupuntura/métodos , Bexiga Urinária/diagnóstico por imagem , Adulto , Ultrassonografia de Intervenção , Adulto Jovem , Pessoa de Meia-Idade , Pontos de Acupuntura
18.
Microb Cell Fact ; 23(1): 25, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238770

RESUMO

BACKGROUND: Although E. coli is generally a well-opted platform for the overproduction of recombinant antigens as heterologous proteins, the optimization of expression conditions to maximize the yield of functional proteins remains empirical. Herein, we developed an optimized E. coli (BL21)-based system for the overproduction of soluble immunoreactive HCV core/envelope proteins that were utilized to establish a novel immunoassay for discrimination of active HCV infection. METHODS: The core/E1-E2 genes were amplified and expressed in E. coli BL21 (DE3) in the absence/presence of glycylglycine. The antigenic performance of soluble proteins was assessed against 63 HCV-seronegative (Ab-) sera that included normal and interferent sera (HBV and/or chronic renal failure), and 383 HCV-seropositive (Ab+) samples that included viremic (chronic/relapsers) and recovered patients' sera. The color intensity (OD450) and S/Co values were estimated. RESULTS: The integration of 0.1-0.4M glycylglycine in the growth media significantly enhanced the solubility/yield of recombinant core and envelope proteins by ~ 225 and 242 fold, respectively. This was reflected in their immunoreactivity and antigenic performance in the developed immunoassay, where the soluble core/E1/E2 antigen mixture showed 100% accuracy in identifying HCV viremic sera with a viral RNA load as low as 3800 IU/mL, without cross-reactivity against normal/interferent HCV-Ab-sera. The ideal S/Co threshold predicting active viremia (> 2.75) showed an AUC value of 0.9362 (95% CI: 0.9132 to 0.9593), with 87.64, 91.23% sensitivity and specificity, and 94.14, 82.11% positive and negative predictive values, respectively. The different panels of samples assayed with our EIA showed a good concordance with the viral loads and also significant correlations with the golden standards of HCV diagnosis in viremic patients. The performance of the EIA was not affected by the immunocompromised conditions or HBV co-infection. CONCLUSION: The applicability of the proposed platform would extend beyond the reported approach, where glycylglycine, low inducer concentration and post-induction temperature, combined with the moderately-strong constitutive promoter enables the stable production of soluble/active proteins, even those with reported toxicity. Also, the newly developed immunoassay provides a cost-effective point-of-care diagnostic tool for active HCV viremia that could be useful in resource-limited settings.


Assuntos
Glicilglicina , Hepatite C , Humanos , Viremia/diagnóstico , Escherichia coli , Sistemas Automatizados de Assistência Junto ao Leito , Solubilidade , Anticorpos Anti-Hepatite C , Hepacivirus/genética , Imunoensaio , Proteínas Recombinantes
19.
Microbiol Immunol ; 68(6): 206-211, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38644589

RESUMO

Colonization resistance, conferred by the host's microbiota through both direct and indirect protective actions, serves to protect the host from enteric infections. Here, we identified the specific members of the gut microbiota that impact gastrointestinal colonization by Citrobacter rodentium, a murine pathogen causing colonic crypt hyperplasia. The gut colonization levels of C. rodentium in C57BL/6 mice varied among breeding facilities, probably due to differences in microbiota composition. A comprehensive analysis of the microbiota revealed that specific members of the microbiota may influence gut colonization by C. rodentium, thus providing a potential link between the two.


Assuntos
Citrobacter rodentium , Infecções por Enterobacteriaceae , Microbioma Gastrointestinal , Trato Gastrointestinal , Camundongos Endogâmicos C57BL , Animais , Citrobacter rodentium/patogenicidade , Citrobacter rodentium/fisiologia , Infecções por Enterobacteriaceae/microbiologia , Camundongos , Trato Gastrointestinal/microbiologia , Colo/microbiologia , Colo/patologia , Fezes/microbiologia , RNA Ribossômico 16S/genética
20.
Toxicol Pathol ; 52(2-3): 99-113, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38757264

RESUMO

A retrospective analysis in C57BL6/J mice used in dietary carcinogenicity studies was performed to determine the survival rate, causes of death and incidences of spontaneous non-tumoral and tumoral findings. Data were collected from 1600 mice from control dose groups of sixteen 18-month carcinogenicity assays performed between 2003 and 2021 at the same test facility with similar environmental conditions and experimental procedures. The survival rate was high in both sexes (81%-85%) and the causes of humane euthanasia or death were mainly non-tumoral (chronic ulcerative dermatitis, atrial thrombosis). Benign tumors were more frequent than malignant tumors and females were more affected than males. Pituitary gland adenoma in females, lymphoma, bronchioloalveolar adenoma, and harderian gland adenoma in both sexes were the most common tumors. Systemic amyloidosis, the most frequent non-tumoral lesion, was observed variably across studies without sex predilection. The analysis by cohort (3 time periods of 6 years) showed a tendency toward higher incidences of lymphoma and pituitary gland adenoma and lower incidences of amyloidosis over time. The results presented here provide for the first time a robust set of control historical data in untreated C57BL/6J mice kept for 18 months contributing to build in depth knowledge of this animal model.


Assuntos
Testes de Carcinogenicidade , Camundongos Endogâmicos C57BL , Animais , Feminino , Masculino , Camundongos , Estudos Retrospectivos , Neoplasias/patologia , Neoplasias/induzido quimicamente , Dieta
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