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1.
J Agric Food Chem ; 72(19): 10879-10896, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38686994

RESUMO

Mammary gland aging is one of the most important problems faced by humans and animals. How to delay mammary gland aging is particularly important. Puerarin is a kind of isoflavone substance extracted from Pueraria lobata, which has anti-inflammatory, antioxidant, and other pharmacological effects. However, the role of puerarin in delaying lipopolysaccharide (LPS)-induced mammary gland aging and its underlying mechanism remains unclear. On the one hand, we found that puerarin could significantly downregulate the expression of senescence-associated secretory phenotype (SASP) and age-related indicators (SA-ß-gal, p53, p21, p16) in mammary glands of mice. In addition, puerarin mainly inhibited the p38MAPK signaling pathway to repair mitochondrial damage and delay mammary gland aging. On the other hand, puerarin could also delay the cellular senescence of mice mammary epithelial cells (mMECs) by targeting gut microbiota and promoting the secretion of gut microbiota metabolites. In conclusion, puerarin could not only directly act on the mMECs but also regulate the gut microbiota, thus, playing a role in delaying the aging of the mammary gland. Based on the above findings, we have discovered a new pathway for puerarin to delay mammary gland aging.


Assuntos
Envelhecimento , Microbioma Gastrointestinal , Isoflavonas , Glândulas Mamárias Animais , Proteínas Quinases p38 Ativadas por Mitógeno , Isoflavonas/farmacologia , Animais , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Feminino , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Envelhecimento/efeitos dos fármacos , Humanos , Pueraria/química , Bactérias/classificação , Bactérias/genética , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Bactérias/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Senescência Celular/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Endogâmicos C57BL
2.
Int J Biol Macromol ; 266(Pt 2): 131151, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38547945

RESUMO

BACKGROUND: Cold as a common environmental stress, causes increased heat production, accelerated metabolism and even affects its production performance. How to improve the adaptability of the animal organism to cold has been an urgent problem. As a key hub of lipid metabolism, the liver can regulate lipid metabolism to maintain energy balance, and O-GlcNAcylation is a kind of important PTMs, which participates in a variety of signaling and mechanism regulation, and at the same time, is very sensitive to changes in stress and nutritional levels, and is the body's "stress receptors" and "nutrient receptors". Therefore, the aim of this experiment was to investigate the effect of cold-induced O-GlcNAcylation on hepatic lipid metabolism, and to explore the potential connection between O-GlcNAcylation and hepatic lipid metabolism. METHODS: To investigate the loss of O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) and the precise impacts of additional cold-induced circumstances on liver mass, shape, and metabolic profile, C57 mice were used as an animal model. Using the protein interactions approach, the mechanism of O-GlcNAcylation, as well as the degradation pathway of acyl-Coenzyme A oxidase 1 (ACOX1), were clarified. Additional in vitro analyses of oleic acid (OA) and OGT inhibitor tetraoxan (Alloxan) (Sigma, 2244-11-3) on lipid breakdown in AML-12 cells. RESULTS: In C57BL/6 mice, deletion of O-GlcNAcylation disrupted lipid metabolism, caused hepatic edema and fibrosis, and altered mitochondrial apoptosis. This group of modifications was made worse by cold induction. The accumulation of medium- and long-chain fatty acids is a hallmark of lipolysis, which is accelerated by the deletion of O-GlcNAcylation, whereas lipid synthesis is slowed down. The association between ACOX1 and OGT at the K48 gene precludes ubiquitinated degradation.


Assuntos
Ácidos Graxos , Metabolismo dos Lipídeos , Ubiquitinação , Animais , Masculino , Camundongos , Ácidos Graxos/metabolismo , Fígado/metabolismo , Camundongos Endogâmicos C57BL , N-Acetilglucosaminiltransferases/metabolismo , Proteólise , Acil-CoA Oxidase/antagonistas & inibidores , Acil-CoA Oxidase/metabolismo , Acetilglucosamina/metabolismo
3.
Nat Commun ; 15(1): 1573, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383547

RESUMO

Intermetallic compounds (IMCs) with fixed chemical composition and ordered crystallographic arrangement are highly desirable platforms for elucidating the precise correlation between structures and performances in catalysis. However, diffusing a metal atom into a lattice of another metal to form a controllably regular metal occupancy remains a huge challenge. Herein, we develop a general and tractable solvothermal method to synthesize the Bi-Pd IMCs family, including Bi2Pd, BiPd, Bi3Pd5, Bi2Pd5, Bi3Pd8 and BiPd3. By employing electrocatalytic CO2 reduction as a model reaction, we deeply elucidated the interplay between Bi-Pd IMCs and key intermediates. Specific surface atomic arrangements endow Bi-Pd IMCs different relative surface binding affinities and adsorption configuration for *OCHO, *COOH and *H intermediate, thus exhibiting substantially selective generation of formate (Bi2Pd), CO (BiPd3) and H2 (Bi2Pd5). This work provides a comprehensive understanding of the specific structure-performance correlation of IMCs, which serves as a valuable paradigm for precisely modulating catalyst material structures.

4.
Int J Biol Macromol ; 254(Pt 3): 127786, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37918588

RESUMO

Valine, a branched-chain amino acid found in dairy cows, has been recognized for its critical role in milk synthesis. However, the precise effect of valine on lactation in dairy cows remains an area of investigation. In our study, bovine mammary epithelial cells (BMECs) were isolated to explore the mechanism through which valine enhances milk synthesis. The results showed that 100 µM valine significantly boosted the milk synthesis via TAS1R1-mTOR-DDX39B signaling pathway in BMECs. Subsequent investigations revealed that DDX39B governs the accumulation of PKM2 in the nuclei of BMECs. This nuclear buildup of PKM2 weakened the interaction between HDAC3 and histone H3, leading to an increase in the acetylation levels of histone H3. In an vivo context, the 0.25 % valine-enriched drinking water notably elevated in the expression of milk protein and fat in these mice. Further examination showed that 0.25 % valine drinking water considerably augmented the protein expression levels of DDX39B, PKM2, and p-mTOR in the mice mammary glands. In summary, our results suggest that valine, by modulating the TAS1R1-mTOR-DDX39B signaling pathway, directs the accumulation of PKM2 in the nucleus. This, in turn, escalates the acetylation levels of histone H3, promoting the synthesis of both milk protein and fat.


Assuntos
Água Potável , Histonas , Feminino , Animais , Bovinos , Camundongos , Histonas/metabolismo , Valina/metabolismo , Acetilação , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Proteínas do Leite/metabolismo , Células Epiteliais
5.
J Agric Food Chem ; 72(1): 390-404, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38154091

RESUMO

Ghrelin regulates diverse physiological activities. However, the effects of this hormone on the milk fat synthesis remain unknown. This study aimed to investigate the effect of acylated ghrelin (AG) on milk fat synthesis by modifying the expression (knockdown or overexpression) of growth hormone secretagogue receptor 1a (GHSR1a) and Th-inducing POK (ThPOK) in primary bovine mammary epithelial cells (BMECs). The results showed that AG significantly increased the triglyceride relative content from 260.83 ± 9.87 to 541.67 ± 8.38 in BMECs via GHSR1a. ThPOK functions as a key regulatory target downstream of AG, activating the PI3K and mTOR signaling pathways to promote milk fat synthesis in BMECs. Moreover, AG-regulated ThPOK by increasing the EP300 activity, which promoted ThPOK acetylation to protect it from proteasomal degradation. In conclusion, AG increases ThPOK acetylation and stabilizes ThPOK through GHSR1a, thereby activating the PI3K/mTOR signaling pathway and ultimately promoting the milk fat synthesis in BMECs.


Assuntos
Leite , Fosfatidilinositol 3-Quinases , Bovinos , Animais , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Leite/metabolismo , Acetilação , Grelina/metabolismo , Grelina/farmacologia , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Células Epiteliais/metabolismo , Glândulas Mamárias Animais/metabolismo
6.
Macromol Rapid Commun ; 44(23): e2300318, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37572085

RESUMO

It is an urgent need to develop efficient solid state cooling technologies and materials with high cycle life. Poly-p-phenylene benzodioxole (PBO) is a high performance fiber with excellent mechanical properties. In this work, for the first time, elasto- and twistocaloric cooling of PBO fibers by stretching and twisting of the PBO fiber bundles is reported. The cooling temperature reaches -0.4 and -1.3 K, for fiber stretching and twisting, respectively. A self-coiled PBO fiber achieves maximum cooling of -3.7 K upon stretching by 35% strain, with an exceptionally high cycle life of 200 000 times. During the twisting of the PBO fibers, reversible changes in the intensity of the diffraction peaks in X-ray diffraction patterns are observed. A strain-sensitive color change application is realized by coating a self-coiled PBO fiber with liquid crystallite dyes. This work provides new perspectives for PBO fibers as a high cycle-life solid-state refrigeration material.


Assuntos
Cicloparafinas , Compostos Heterocíclicos , Temperatura Baixa , Temperatura , Benzodioxóis
7.
Chempluschem ; 88(9): e202300262, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37551133

RESUMO

In recent years, the development of electrochemical biosensors for uric acid has made great achievements. Firstly, uric acid electrochemical biosensors were classified according to their reaction mechanism. Then, the reaction mechanism of the uric acid sensor and the application of nano-modified materials were deeply analyzed from the perspective of non-enzyme and enzymes. In this paper, the catalytic oxidation capacity, enzyme adsorption effect, conductivity, robustness, detection range, and detection limit of uric acid sensors were discussed and compared. Finally, the advantages of acid-sensitive electrochemical biosensors were summarized, and the constructive recommendations were proposed for improving the deficiencies of acid biosensors. The potential for further development in this area was also discussed.


Assuntos
Técnicas Biossensoriais , Ácido Úrico , Oxirredução
8.
Adv Mater ; 35(32): e2212112, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37326574

RESUMO

The axial orientation of molecular chains always results in an increase in fiber strength and a decrease in toughness. Here, taking inspiration from the skin structure, artificial spider silk with a buckled sheath-core structure is developed, with mechanical strength and toughness reaching 1.61 GPa and 466 MJ m-3 , respectively, exceeding those of Caerostris darwini silk. The buckled structure is achieved by nano-pulley combing of polyrotaxane hydrogel fibers through cyclic stretch-release training, which exhibits axial alignment of the polymer chains in the fiber core and buckling in the fiber sheath. The artificial spider silk also exhibits excellent supercontraction behavior, achieving a work capacity of 1.89 kJ kg-1 , and an actuation stroke of 82%. This work provides a new strategy for designing high-performance and intelligent fiber materials.


Assuntos
Seda , Aranhas , Animais , Seda/química , Estresse Mecânico
10.
Chem Biol Interact ; 379: 110533, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37150497

RESUMO

Tartary buckwheat flavonoids (TBF) are active components extracted from Tartary buckwheat, which have abundant biological effects. According to this study, we investigated the effect of TBF on high-fat diet (HFD)-induced kidney fibrosis and its related mechanisms. In vivo, we established an HFD-induced kidney fibrosis model in mice and administered TBF. The results showed that TBF was able to alleviate kidney injury and inflammatory response. Subsequently, the mRNA levels between the HFD group and the TBF + HFD group were detected using RNA-seq assay. According to the gene set enrichment analysis (GSEA) and Kyoto Encyclopedia of Genes and Genomes (KEGG) results, the differential genes were enriched in lipid metabolism and mitogen-activated protein kinases(MAPK) signaling pathways. We examined the protein expression of lipid metabolism-related pathways and the level of lipid metabolism. The results showed that TBF significantly activated the adenosine monophosphate activated protein kinase/acetyl-CoA carboxylase (AMPK/ACC) pathway and effectively reduced kidney total cholesterol (TC), triglyceride (TG) and low-density lipoproteinc cholesterol (LDL-C) levels and increased high-density lipoprotein cholesterol (HDL-C) levels in mice. TBF also inhibited transforming growth factor-ß1/Smad (TGF-ß1/Smad) and MAPK signaling pathways, thus slowing down the kidney fibrosis process. In vitro, using palmitic acid (PA) to stimulate TCMK-1 cells, the in vivo results similarly demonstrated that TBF could alleviate kidney fibrosis in HFD mice by inhibiting TGF1/Smad signaling pathway and MAPK signaling pathway.


Assuntos
Fagopyrum , Nefropatias , Camundongos , Animais , Fator de Crescimento Transformador beta1/metabolismo , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Fagopyrum/metabolismo , Dieta Hiperlipídica/efeitos adversos , Transdução de Sinais , Fibrose , Rim/metabolismo , Nefropatias/tratamento farmacológico , Nefropatias/etiologia , Nefropatias/patologia , Colesterol
11.
Exp Hematol Oncol ; 12(1): 15, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36721229

RESUMO

BACKGROUND: Neutrophil extracellular traps (NETs) is the key means for neutrophils to resist bacterial invasion. Sepsis is a systemic inflammatory response syndrome caused by infection. METHODS: In our study, qRT-PCR was used to detect the gene expression in neutrophils, Western blot was used to detect the protein expression in mouse tissues and neutrophils, flow cytometry was used to detect the purity of neutrophils in the whole blood and immunofluorescence was used to detect the NETs formation. RESULTS: In this study, we analyzed the NETs formation in the blood of patients with sepsis. The results showed that a large number of NETs appeared. And the expression of GPR109A in neutrophils of patients with sepsis was significantly up regulated. Then we collected neutrophils from WT mice and GPR109A-/- mice and found that GPR109A knockout could significantly inhibit the early NETs formation of neutrophils. The results also showed that knockout of GPR109A or inhibition of the NETs formation could increase the inflammatory response of liver, spleen, lung and kidney in mice, thus affecting the disease process of sepsis. Then we observed the death of mice in 16 days. The results showed that inhibiting the NETs formation could significantly affect the early mortality of mice, while knocking out GPR109A could directly affect the mortality of the whole period. CONCLUSIONS: This study confirmed the regulatory effect of GPR109A on early NETs formation for the first time, and provided a new target for the treatment of sepsis.

12.
J Therm Biol ; 110: 103375, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36462887

RESUMO

Lysine, as the first limiting amino acid in dairy cows, has been shown to play an important role in milk synthesis and cell proliferation. However, the underlying mechanism remains unclear. In this study, we isolated bovine primary mammary epithelial cells (BMECs) and studied the mechanism in which lysine promotes cell proliferation and ß-casein synthesis through overexpression and knockdown of CDK1 and supplements BCH, U0126, and rapamycin in BMECs. Results show that 0.7 mM lysine can significantly promote cell proliferation and the synthesis of ß-casein in BMECs. In addition, lysine activates the ERK signaling pathway to promote the expression of CDK1. Further studies have shown that CDK1 can promote cell proliferation and the synthesis of ß-casein through the mTOR signaling pathway in BMECs. Lastly, lysine can promote cell proliferation and the synthesis of ß-casein through SLC6A14 in BMECs. The above results indicate that lysine promotes cell proliferation and the synthesis of ß-casein through the SLC6A14-ERK-CDK1-mTOR signaling pathway in BMECs.


Assuntos
Caseínas , Sistema de Sinalização das MAP Quinases , Feminino , Bovinos , Animais , Lisina , Transdução de Sinais , Células Epiteliais , Proliferação de Células , Serina-Treonina Quinases TOR
13.
Metabolites ; 12(11)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36355118

RESUMO

Dairy cow mammary gland fibrosis causes huge economic losses to livestock production, however, research on dairy cow mammary gland fibrosis is in its infancy and it lacks effective treatments. Therefore, the purpose of this experiment was to explore the correlation between mastitis and fibrosis and mitochondrial damage, and to further explore its pathogenesis. In vivo, mammary tissue and milk samples were collected from healthy cows (n = 10) and mastitis cows (n = 10). The results of the study showed that compared with the control group, the mastitis tissue showed tissue damage, accumulation of collagen fibers, and the content of TGF-ß1 in mammary tissue and milk was significantly increased; the level of inflammatory mediators was significantly increased; the fibrotic phenotype, collagen 1, α-SMA, vimentin gene, and protein levels were significantly increased, while the E-cadherin gene and protein levels were significantly decreased. In vitro, based on TGF-ß1-induced bMECs, the above experimental results were further confirmed, and TGF-ß1 significantly promoted the fibrotic phenotype of bMECs. On the other hand, in vivo results showed that fibrotic mammary tissue had a significantly stronger mitochondrial damage phenotype and significantly higher ROS than the control group. In vitro, the results also found that TGF-ß1 induced a significant increase in the mitochondrial damage phenotype of bMECs, accompanied by a large amount of ROS production. Furthermore, in a TGF-ß1-induced bMEC model, inhibiting the accumulation of ROS effectively alleviated the elevated fibrotic phenotype of TGF-ß1-induced bMECs. In conclusion, the fibrotic phenotype of mammary gland tissue in dairy cows with mastitis was significantly increased, and mastitis disease was positively correlated with mammary fibrotic lesions. In an in vitro and in vivo model of cow mammary fibrosis, bMECs have impaired mitochondrial structure and dysfunction. Inhibiting the accumulation of ROS effectively alleviates the elevated fibrotic phenotype, which may be a potential therapeutic approach to alleviate mammary fibrosis.

14.
J Agric Food Chem ; 70(36): 11324-11335, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36040348

RESUMO

Cell-death-inducing DNA fragmentation factor-α-like effector A (CIDEA) is a lipid-droplet-associated protein that helps to promote lipid metabolism in adipocytes of mice and humans. However, studies on the regulatory mechanism of CIDEA on lipid metabolism in the mammary glands of dairy cows are rare. Therefore, the role of CIDEA in bovine mammary epithelial cells (bMECs) was investigated in this study. The CIDEA expression levels in the mammary glands of high-fat-milk-producing cows were significantly higher compared to those in low-fat-milk-producing cows. Results of in vitro studies in bMECs showed that the inhibition of CIDEA inhibited the expression of fatty acid synthesis-related genes and triglyceride (TAG) synthesis-related genes. Conversely, the overexpression of CIDEA leads to an increase in the content of TAG and fatty acid. The results of mechanistic studies indicated that the overexpression of CIDEA inhibits AMP-activated protein kinase (AMPK) activity, which enhances the expression of peroxisome proliferator-activated receptor-γ (PPARγ) and consequently increases the TAG content. Furthermore, the overexpression of CIDEA promoted the nuclear translocation of sterol regulatory element-binding protein 1 (SREBP1). Therefore, a theoretical framework is provided by this study for the regulation of lipid metabolism in dairy cows by means of nutrition and the hormone targeting of CIDEA.


Assuntos
Glândulas Mamárias Animais , PPAR gama , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Bovinos , Células Epiteliais/metabolismo , Ácidos Graxos/metabolismo , Feminino , Humanos , Glândulas Mamárias Animais/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
15.
J Anim Physiol Anim Nutr (Berl) ; 106(6): 1420-1430, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35923149

RESUMO

Lysine is one of the essential amino acids. The effect of lysine on milk protein and milk fat anabolism has been reported, but the effect on mammary glands development has not been studied in detail. The normal development of the mammary glands at puberty is crucial to lactation of mammals. In this study, to explore the effect of lysine on mammary glands development, we fed different concentrations of lysine (0.025%, 0.05%, 0.1%) to pubertal mice and found that the addition of 0.1% lysine to drinking water significantly promoted mammary glands development. Furthermore, we treated mMECs (mouse mammary epithelial cells) with different concentrations of lysine (0, 0.2, 0.4, 0.6, 0.8 and 1 mM) to explore the underlying mechanism, and found that lysine promoted the proliferation of mMECs and development of mammary glands through PI3K/AKT/mTOR signalling pathway in pubertal mice. Overall, the results of this study revealed that lysine activated the PI3K/AKT/mTOR signal axis, elevated protein concentrations of cell proliferation markers, such as PCNA, Cyclin D1 and D3, and enhanced the proliferation of mMECs, finally promoted the murine mammary glands development at puberty.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Feminino , Camundongos , Animais , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Lisina/farmacologia , Glândulas Mamárias Animais , Maturidade Sexual , Serina-Treonina Quinases TOR/metabolismo , Células Epiteliais , Mamíferos/metabolismo
16.
J Agric Food Chem ; 70(34): 10620-10634, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35973099

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is among the most prevalent chronic liver diseases around the globe. The accumulation of lipids in the liver and oxidative stress are important pathological mechanisms of NAFLD. Astaxanthin (AT) is a carotenoid extracted from shrimps and crabs with beneficial biological activities, including anti-oxidative and anti-inflammatory activities. 16S microflora sequencing, H&E staining, and the western blot technique were employed to investigate the impacts of AT on a high-fat diet (HFD)-induced NAFLD. Significant mitigation in lipid metabolism-related disorders and decreased oxidative stress in HFD-induced mice were observed due to AT, and significant changes in the gut flora of the model mice were also observed. The in vitro study showed that AT considerably lowered the protein expression level of fatty acid synthetase (FAS), sterol regulatory element-binding protein-1c (SREBP-1c), and acetyl-COA carboxylase (ACC) and increased the protein expression of nuclear factor-E2 associated factor 2 (Nrf2) and AMP-activated protein kinase (AMPK) in oleic acid (OA) and palmitic acid (PA)-induced HepG2 cells. Additionally, mechanistic studies revealed that compound C (AMPK inhibitor, CC) inhibited the regulatory effect of AT on the SREBP-1c and Nrf2 signaling pathways. In conclusion, AT can inhibit the SREBP-1c, FAS, and ACC signaling pathways, activate the AMPK and Nrf2 signaling pathways, and improve the structure of intestinal flora.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Xantofilas , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Animais , Células Hep G2 , Humanos , Metabolismo dos Lipídeos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Xantofilas/farmacologia
17.
Int Immunopharmacol ; 110: 109009, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35816944

RESUMO

Neutrophil extracellular traps (NETs) are an important means by which the body fights against exogenous bacteria. However, studies have shown that excessive NETs release can damage other cells. Accumulating evidence has shown that butyric acid can alleviate the inflammatory response of cells. However, the effect of butyric acid on Staphylococcus aureus-induced NETs formation and its underlying mechanism are still unclear. In this study, western blotting, immunofluorescence and CCK-8 assays were used to examine the effect of NETs formation by sodium butyrate (NaB). The results showed that NaB suppressed the release of S. aureus-induced NETs formation, as indicated by decreases in the levels of DNA, histones, myeloperoxidase, and neutrophil elastase. S. aureus can induce autophagy, and autophagy plays a key role in the formation of NETs. Our data showed that NaB activated mammalian target of rapamycin (mTOR) and the kinases protein kinase B (AKT) and unc-51 like kinase 1 (ULK1) at Ser757 and inhibited AMP-activated protein kinase (AMPK). To explore whether NaB inhibited the formation of NETs by inhibiting autophagy, we added 3-methyladenine (autophagy inhibitor) (3-MA, 5 mM) to bovine neutrophils, and the results showed that 3-MA significantly inhibited NETs release. Furthermore, we found that NETs and their component histones exhibited significantly increased the cytotoxic effects on bovine mammary epithelial cells (BMECs), indicating that NETs and their component histones play a key role in BMEC damage. In conclusion, NaB can reduce the excessive formation of NETs by inhibiting autophagy, thus reducing the damaging effect of NETs on BMECs.


Assuntos
Armadilhas Extracelulares , Animais , Ácido Butírico/farmacologia , Bovinos , Células Epiteliais/metabolismo , Histonas/metabolismo , Mamíferos , Neutrófilos , Staphylococcus aureus/metabolismo
18.
iScience ; 25(6): 104449, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35677643

RESUMO

The envelope glycoprotein (Env) is the sole target for neutralizing antibodies against HIV and the most rapidly evolving, variable part of the virus. High-resolution structures of Env trimers captured in the pre-fusion, closed conformation have revealed a high degree of structural similarity across diverse isolates. Biophysical data, however, indicate that Env is highly dynamic, and the level of dynamics and conformational sampling is believed to vary dramatically between HIV isolates. Dynamic differences likely influence neutralization sensitivity, receptor activation, and overall trimer stability. Here, using hydrogen/deuterium-exchange mass spectrometry (HDX-MS), we have mapped local dynamics across native-like Env SOSIP trimers from diverse isolates. We show that significant differences in epitope order are observed across most sites targeted by broadly neutralizing antibodies. We also observe isolate-dependent conformational switching that occurs over a broad range of timescales. Lastly, we report that hyper-stabilizing mutations that dampen dynamics in some isolates have little effect on others.

19.
Microbiol Spectr ; 10(3): e0243721, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35499354

RESUMO

Timely diagnosis and treatment of hepatitis C virus (HCV) infection may prevent its transmission. We evaluated the performance and cost reductions of the pooled plasma HCV RNA testing strategy to identify acute HCV infections among people living with HIV (PLWH). PLWH with sexually transmitted infections, elevated aminotransferases within the past 6 months or past HCV infections (high-risk) and those without (low-risk) were enrolled prospectively. Participants underwent three-stage pooled plasma HCV RNA testing every 12 to 24 weeks until detection of HCV RNA or completion of a 48-week follow-up. The three-stage strategy combined 20 individual specimens into a stage 1 pool, 5 individual specimens from the stage 1 pool that tested positive for HCV RNA in the stage 2 mini-pool, followed by testing of individual specimens of the stage 2 mini-pool tested positive for HCV RNA. A simulation was constructed to investigate the cost reductions and pooled sensitivity and specificity under different combinations of HCV prevalence and pool/mini-pool sizes. Between June 25, 2019 and March 31, 2021, 32 cases of incident HCV viremia were identified in 760 high-risk PLWH that were enrolled 834 times, giving an incidence rate of 56.6 per 1000 person-years of follow-up (PYFU). No cases of HCV viremia were identified in 557 low-risk PLWH during a total of 269.2 PYFU. Simulation analysis suggested that this strategy could reduce HCV RNA testing cost by 50% to 86% with HCV viremia prevalence of 1% to 5% and various pooled sizes despite compromised pooled sensitivity. This pooled plasma HCV RNA testing strategy is cost-saving to identify acute HCV infections in high-risk populations with HCV viremia prevalence of 1% to 5%. IMPORTANCE Our three-stage pooled plasma HCV RNA testing successfully identified HCV viremia in high-risk PLWH with a testing cost reduction of 84.5%. Simulation analysis offered detailed information regarding the selection of pool and mini-pool sizes in settings of different HCV epidemiology and the performance of HCV RNA testing to optimize the cost reduction.


Assuntos
Infecções por HIV , Hepatite C , Hepacivirus/genética , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Humanos , RNA , Testes Sorológicos , Viremia/diagnóstico
20.
Sci Total Environ ; 839: 156057, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35605863

RESUMO

Existing receptor-model-based source apportionment methods failed to derive source contributions to accumulation of soil heavy metals (SHMs). In this research, a dynamics-simulation-based source apportionment approach (DSSA) was developed by integrating mathematical models of source release, diffusion and deposition pathway, and receptor accumulation, to quantify accumulative contributions of SHMs. The case study was carried out in a complex industrialized region in southeast China to investigate pollution situation of SHMs (Zn, Pb, Ni, As, Cd, and Cr). The results showed that SHMs distributions were affected by seasonal variation and near-surface meteorology, which could be sequenced by correlation coefficient as temperature (0.968) > humidity (0.552) > precipitation (0.389) > wind speed (0.386). The source categories and corresponding contribution rates were identified as: i) battery plant to Zn (72.32%) and Pb (71.73%), ii) traffic to Ni (64.55%), iii) traffic and agriculture to Cd (43.26%, 41.63%), iv) agriculture to As (75.30%) and Cr (60.05%), which was similar to the results of positive matrix factorization (PMF). Furthermore, DSSA could illustrate SHMs migration process from source to receptor. The uncertainty analysis further proved the distinct advantages of DSSA. The results of this research could predict pollutant enrichment and could provide new perspective for environment and public health management.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio , China , Monitoramento Ambiental/métodos , Chumbo , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
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