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1.
Nature ; 600(7890): 664-669, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34937898

RESUMEN

More than a decade of research on the electrocaloric (EC) effect has resulted in EC materials and EC multilayer chips that satisfy a minimum EC temperature change of 5 K required for caloric heat pumps1-3. However, these EC temperature changes are generated through the application of high electric fields4-8 (close to their dielectric breakdown strengths), which result in rapid degradation and fatigue of EC performance. Here we report a class of EC polymer that exhibits an EC entropy change of 37.5 J kg-1 K-1 and a temperature change of 7.5 K under 50 MV m-1, a 275% enhancement over the state-of-the-art EC polymers under the same field strength. We show that converting a small number of the chlorofluoroethylene groups in poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) terpolymer into covalent double bonds markedly increases the number of the polar entities and enhances the polar-nonpolar interfacial areas of the polymer. The polar phases in the polymer adopt a loosely correlated, high-entropy state with a low energy barrier for electric-field-induced switching. The polymer maintains performance for more than one million cycles at the low fields necessary for practical EC cooling applications, suggesting that this strategy may yield materials suitable for use in caloric heat pumps.

2.
PLoS Genet ; 17(10): e1009832, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34673774

RESUMEN

The mammalian target of rapamycin complex 1 (mTORC1) senses multiple stimuli to regulate anabolic and catabolic processes. mTORC1 is typically hyperactivated in multiple human diseases such as cancer and type 2 diabetes. Extensive research has focused on signaling pathways that can activate mTORC1 such as growth factors and amino acids. However, less is known about signaling cues that can directly inhibit mTORC1 activity. Here, we identify A-kinase anchoring protein 13 (AKAP13) as an mTORC1 binding protein, and a crucial regulator of mTORC1 inhibition by G-protein coupled receptor (GPCR) signaling. GPCRs paired to Gαs proteins increase cyclic adenosine 3'5' monophosphate (cAMP) to activate protein kinase A (PKA). Mechanistically, AKAP13 acts as a scaffold for PKA and mTORC1, where PKA inhibits mTORC1 through the phosphorylation of Raptor on Ser 791. Importantly, AKAP13 mediates mTORC1-induced cell proliferation, cell size, and colony formation. AKAP13 expression correlates with mTORC1 activation and overall lung adenocarcinoma patient survival, as well as lung cancer tumor growth in vivo. Our study identifies AKAP13 as an important player in mTORC1 inhibition by GPCRs, and targeting this pathway may be beneficial for human diseases with hyperactivated mTORC1.


Asunto(s)
Proteínas de Anclaje a la Quinasa A/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Antígenos de Histocompatibilidad Menor/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal/fisiología , Células A549 , Animales , Línea Celular , Línea Celular Tumoral , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Células HCT116 , Células HEK293 , Humanos , Ratones , Células PC-3 , Fosforilación/fisiología
3.
Eur J Nutr ; 62(7): 2873-2890, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37392244

RESUMEN

BACKGROUND AND AIMS: Amino acids (AAs) not only constitute milk protein but also stimulate milk synthesis through the activation of mTORC1 signaling, but which amino acids that have the greatest impact on milk fat and protein synthesis is still very limited. In this study, we aimed to identify the most critical AAs involved in the regulation of milk synthesis and clarify how these AAs regulate milk synthesis through the G-protein-coupled receptors (GPCRs) signaling pathway. METHODS: In this study, a mouse mammary epithelial cell line (HC11) and porcine mammary epithelial cells (PMECs) were selected as study subjects. After treatment with different AAs, the amount of milk protein and milk fat synthesis were detected. Activation of mTORC1 and GPCRs signaling induced by AAs was also investigated. RESULTS: In this study, we demonstrate that essential amino acids (EAAs) are crucial to promote lactation by increasing the expression of genes and proteins related to milk synthesis, such as ACACA, FABP4, DGAT1, SREBP1, α-casein, ß-casein, and WAP in HC11 cells and PMECs. In addition to activating mTORC1, EAAs uniquely regulate the expression of calcium-sensing receptor (CaSR) among all amino-acid-responsive GPCRs, which indicates a potential link between CaSR and the mTORC1 pathway in mammary gland epithelial cells. Compared with other EAAs, leucine and arginine had the greatest capacity to trigger GPCRs (p-ERK) and mTORC1 (p-S6K1) signaling in HC11 cells. In addition, CaSR and its downstream G proteins Gi, Gq, and Gßγ are involved in the regulation of leucine- and arginine-induced milk synthesis and mTORC1 activation. Taken together, our data suggest that leucine and arginine can efficiently trigger milk synthesis through the CaSR/Gi/mTORC1 and CaSR/Gq/mTORC1 pathways. CONCLUSION: We found that the G-protein-coupled receptor CaSR is an important amino acid sensor in mammary epithelial cells. Leucine and arginine promote milk synthesis partially through the CaSR/Gi/mTORC1 and CaSR/Gq/mTORC1 signaling systems in mammary gland epithelial cells. Although this mechanism needs further verification, it is foreseeable that this mechanism may provide new insights into the regulation of milk synthesis.


Asunto(s)
Proteínas de la Leche , Receptores Sensibles al Calcio , Ratones , Femenino , Animales , Porcinos , Leucina/farmacología , Leucina/metabolismo , Receptores Sensibles al Calcio/genética , Receptores Sensibles al Calcio/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina , Arginina/farmacología , Aminoácidos/metabolismo , Caseínas/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Glándulas Mamarias Animales/metabolismo , Células Epiteliales/metabolismo
4.
BMC Bioinformatics ; 23(1): 181, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35578189

RESUMEN

BACKGROUND: Stomach adenocarcinoma (STAD) is a common malignant tumor in the world and its prognosis is poor, miRNA plays a role mainly by influencing the expression of mRNAs, and participates in the occurrence and development of tumors. However, reliable miRNA prognostic models for stomach adenocarcinoma remain to be identified. RESULTS: Using the data from the Cancer Genome Atlas (TCGA), a prognostic model of stomach adenocarcinoma was established including tumor stage and expression levels of 4 miRNAs (hsa-miR-379-3p, hsa-miR-2681-3p, hsa-miR-6499-5p and hsa-miR-6807-3p). A total of 50 ultimate target genes of these miRNAs were obtained through prediction. Enrichment analysis revealed that target genes were mainly concentrated in neural function and TGF-ß and FoxO signaling pathways. Survival analysis showed that three model miRNAs (hsa-miR-379-3p, hsa-miR-2681-3p and hsa-miR-6807-3p) and five final target genes (DLC1, LRFN5, NOVA1, POU3F2 and PRICKLE2) were associated with the patient's overall survival outcome. CONCLUSIONS: We used bioinformatics methods to screen new prognostic miRNA markers from TCGA and established a prognostic model of STAD, so as to provide a basis for the diagnosis, prognosis, and treatment of STAD in the future.


Asunto(s)
Adenocarcinoma , MicroARNs , Neoplasias Gástricas , Adenocarcinoma/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Proteínas Activadoras de GTPasa , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Gástricas/genética , Proteínas Supresoras de Tumor
5.
J Cell Physiol ; 237(10): 3705-3716, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35892164

RESUMEN

As one of the most important organs in animals, the intestine is responsible for nutrient absorption and acts as a barrier between the body and the environment. Intestinal physiology and function require the participation of energy. 5'-adenosine monophosphate-activated protein kinase (AMPK), a classical and highly expressed energy regulator in intestinal cells, regulates the process of nutrient absorption and barrier function and is also involved in the therapy of intestinal diseases. Studies have yielded findings that AMPK regulates the absorption of glucose, amino acids, and fatty acids in the intestine primarily by regulating transportation systems, as we detailed here. Moreover, AMPK is involved in the regulation of the intestinal mechanical barrier and immune barrier through manipulating the expression of tight junctions, antimicrobial peptides, and secretory immunoglobulins. In addition, AMPK also participates in the regulation of intestinal diseases, which indicates that AMPK is a promising therapeutic target for intestinal diseases and cancer. In this review, we summarized the current understanding regarding how AMPK regulates intestinal nutrient absorption, barrier function, and intestinal diseases.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Enfermedades Intestinales , Proteínas Quinasas Activadas por AMP/metabolismo , Adenosina Monofosfato , Aminoácidos , Animales , Ácidos Grasos , Glucosa , Intestinos , Nutrientes
6.
Cell Commun Signal ; 20(1): 25, 2022 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-35248054

RESUMEN

BACKGROUND: The mammary gland is responsible for milk production and secretion, which is critical for neonatal health during lactation. Lactation efficiency is largely affected by energy status with unclear mechanism. RESULTS: In the current study, we found that synthesis of milk fat and protein was significantly inhibited under energy-deficient conditions, which is accompanied with AMP-activated protein kinase (AMPK) activation. Modulating the AMPK signaling pathway directly or indirectly affects the synthesis of milk fat and protein. Besides mammalian target of rapamycin complex 1 (mTORC1) signaling in the regulation of milk synthesis, we discovered that AMPK mainly regulates the synthesis of milk protein through prolactin signaling. Mechanistically, AMPK triggers the ubiquitination of prolactin receptor (PrlR) through regulating the activity of ß-transducin repeat-containing protein (ß-TrCP, an E3 ligase). Subsequently, PrlR is degraded by the endocytosis process of lysosomes, which further attenuates prolactin signaling. In addition, our results revealed that AMPK activation inhibits milk fat synthesis through decreasing and accelerating de novo synthesis and ß-oxidation of fatty acids, respectively. To be precise, AMPK activation inhibits rate limiting enzymes and transcriptional regulatory factors involved in de novo fatty acid synthesis and decreases the acetylation process of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) to strengthen the oxidation of fatty acids. CONCLUSIONS: Taken together, AMPK regulates the synthesis of milk not only depends on canonical mTORC1 signaling and key rate-limiting enzymes, but also through manipulating the degradation of PrlR and the acetylation of PGC-1α. Video Abstract.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Receptores de Prolactina , Proteínas Quinasas Activadas por AMP/metabolismo , Ácidos Grasos/metabolismo , Femenino , Humanos , Recién Nacido , Diana Mecanicista del Complejo 1 de la Rapamicina , Prolactina , Factores de Transcripción/metabolismo
7.
J Opt Soc Am A Opt Image Sci Vis ; 39(4): 523-534, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35471374

RESUMEN

For structure parameter calibration of a binocular stereo vision system equipped with polarizers, the optimal calibration polarization angle needs to be determined. There are no corresponding solutions for the determination of the optimal polarization angle of structure parameter calibration. Furthermore, existing research considers the polarization angle that causes the image to possess the lowest brightness (gray value) as the optimal polarization angle. This reduces image contrast, and eventually the texture information of the image is lost, which also affects the accuracy of feature extraction. In this paper, we propose a new calibration method for the structure parameters of a binocular stereo vision system equipped with polarizers. We calculated the pose of the target relative to each camera for different polarization angles. The sum of the object-space errors corresponding to each polarization angle was considered as the evaluation criterion to determine the optimal calibration polarization angle. The calibration of structure parameters was finished using images captured on the premise of the optimal calibration polarization angle. This angle can also be considered as the reference of the polarization angle for measurement. Experiment results show that using the calibration results of our method, the reconstructed length error of a 275×200mm target was less than ±0.052mm, the reconstructed linear displacement error was less than ±0.048mm for the range of 0-30 mm, and the reconstructed rotary angle error was less than ±0.048∘ for the range of-30∘-30∘.

8.
Nutr Res Rev ; 35(2): 282-294, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-34233775

RESUMEN

Tremendous progress has been made in the field of ferroptosis since this regulated cell death process was first named in 2012. Ferroptosis is initiated upon redox imbalance and driven by excessive phospholipid peroxidation. Levels of multiple intracellular nutrients (iron, selenium, vitamin E and coenzyme Q10) are intimately related to the cellular antioxidant system and participate in the regulation of ferroptosis. Dietary intake of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) regulates ferroptosis by directly modifying the fatty acid composition in cell membranes. In addition, amino acids and glucose (energy stress) manipulate the ferroptosis pathway through the nutrient-sensitive kinases mechanistic target of rapamycin complex 1 (mTORC1) and AMP-activated protein kinase (AMPK). Understanding the molecular interaction between nutrient signals and ferroptosis sensors might help in the identification of the roles of ferroptosis in normal physiology and in the development of novel pharmacological targets for the treatment of ferroptosis-related diseases.


Asunto(s)
Ferroptosis , Humanos , Transducción de Señal/fisiología , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Nutrientes
9.
J Integr Neurosci ; 21(5): 135, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-36137970

RESUMEN

BACKGROUND: Sleep deprivation reduced the time to induce anesthesia by propofol and isoflurane and prolonged the time to recovery. However, it is unknown whether sleep deprivation affects the potency of inhaled anesthetics. In this study, the effect of sleep deprivation on sevoflurane anesthetic potency was explored. METHODS: Ten animals received the following behavioral interventions in turn (ad libitum activity, 24 h sleep deprivation, 48 h sleep deprivation, 72 h sleep deprivation). After each behavioral intervention, the 50% effective dose for loss of righting reflex (LORR ED50) was determined to evaluate the potency of sevoflurane in inducing unconsciousness in mice. Repeated-measures analysis of variance was used to compare our behavioral interventions statistically, post hoc multiple comparisons were made using the Bonferroni test. RESULTS: Sleep deprivation decreased the sevoflurane LORR ED50 significantly (p = 0.0003). However, the effect of duration of sleep deprivation on LORR ED50 was not statistically significant (p > 0.9999). CONCLUSIONS: Sleep deprivation can increase the anesthetic potency of sevoflurane regardless of duration of sleep deprivation.


Asunto(s)
Anestésicos por Inhalación , Isoflurano , Propofol , Anestésicos por Inhalación/farmacología , Animales , Isoflurano/farmacología , Ratones , Propofol/farmacología , Sevoflurano/farmacología , Privación de Sueño
10.
Br J Nutr ; 125(1): 62-70, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-32792028

RESUMEN

The present study was conducted to evaluate the impact of dietary fully oxidised ß-carotene (OxBC, C40H60O15) supplementation during the perinatal period on immune status and productivity in a sow model. At day 85 of pregnancy, 150 sows were allocated to one of three dietary treatments with fifty sows per treatment. The three experimental diets were supplemented with 0, 4 or 8 mg/kg OxBC in the basal diet. The feeding trial was conducted from gestation day 85 until day 21 of lactation. Dietary OxBC supplementation greatly enhanced colostrum IgM, IgA and IgG levels, and the IgM and IgG content of 14-d milk. Dietary OxBC supplementation decreased the TNF-α and IL-8 levels in colostrum, as well as the TNF-α and IL-18 levels in 14-d milk. There was also a tendency towards an increase in the soluble CD14 level in 14-d milk. Although dietary treatments did not affect average daily feed intake nor backfat thickness loss during lactation, dietary OxBC supplementation tended to enhance litter weight and individual piglet weight at weaning. There was a trend towards increased lactose concentration in 14-d milk with increasing dietary OxBC. It is concluded that dietary supplementation with OxBC during the perinatal period enhances the lactose concentration of sow milk and the immune status of sows, which is reflected by improved cytokine status and immunoglobulin concentrations in colostrum and milk, and thus tending to increase litter weight and individual piglet weight at weaning. The results also provide a scientific nutritional reference for perinatal mothers due to the biological similarity between pigs and humans.


Asunto(s)
Animales Recién Nacidos/crecimiento & desarrollo , Suplementos Dietéticos , Inmunidad/efectos de los fármacos , Reproducción/efectos de los fármacos , beta Caroteno/farmacología , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Femenino , Fenómenos Fisiologicos Nutricionales Maternos , Embarazo , Porcinos
11.
Nature ; 523(7562): 576-9, 2015 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-26223625

RESUMEN

Dielectric materials, which store energy electrostatically, are ubiquitous in advanced electronics and electric power systems. Compared to their ceramic counterparts, polymer dielectrics have higher breakdown strengths and greater reliability, are scalable, lightweight and can be shaped into intricate configurations, and are therefore an ideal choice for many power electronics, power conditioning, and pulsed power applications. However, polymer dielectrics are limited to relatively low working temperatures, and thus fail to meet the rising demand for electricity under the extreme conditions present in applications such as hybrid and electric vehicles, aerospace power electronics, and underground oil and gas exploration. Here we describe crosslinked polymer nanocomposites that contain boron nitride nanosheets, the dielectric properties of which are stable over a broad temperature and frequency range. The nanocomposites have outstanding high-voltage capacitive energy storage capabilities at record temperatures (a Weibull breakdown strength of 403 megavolts per metre and a discharged energy density of 1.8 joules per cubic centimetre at 250 degrees Celsius). Their electrical conduction is several orders of magnitude lower than that of existing polymers and their high operating temperatures are attributed to greatly improved thermal conductivity, owing to the presence of the boron nitride nanosheets, which improve heat dissipation compared to pristine polymers (which are inherently susceptible to thermal runaway). Moreover, the polymer nanocomposites are lightweight, photopatternable and mechanically flexible, and have been demonstrated to preserve excellent dielectric and capacitive performance after intensive bending cycles. These findings enable broader applications of organic materials in high-temperature electronics and energy storage devices.

12.
Int J Mol Sci ; 22(3)2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33525494

RESUMEN

This study aimed to examine the effects of increasing levels of three 18-carbon fatty acids (stearate, oleate and linoleate) on mammary lipogenesis, and to evaluate their effects on the milk lipogenic pathway in porcine mammary epithelial cells (pMECs). We found that increasing the three of 18-carbon fatty acids enhanced the cellular lipid synthesis in a dose-dependent manner, as reflected by the increased (triacylglycerol) TAG content and cytosolic lipid droplets in pMECs. The increased lipid synthesis by the three 18-carbon fatty acids was probably caused by the up-regulated expression of major genes associated with milk fat biosynthesis, including CD36 (long chain fatty acid uptake); GPAM, AGPAT6, DGAT1 (TAG synthesis); PLIN2 (lipid droplet formation); and PPARγ (regulation of transcription). Western blot analysis of CD36, DGAT1 and PPARγ proteins confirmed this increase with the increasing incubation of 18-carbon fatty acids. Interestingly, the mRNA expressions of ACSL3 and FABP3 (fatty acids intracellular activation and transport) were differentially affected by the three 18-carbon fatty acids. The cellular mRNA expressions of ACSL3 and FABP3 were increased by stearate, but were decreased by oleate or linoleate. However, the genes involved in fatty acid de novo synthesis (ACACA and FASN) and the regulation of transcription (SREBP1) were decreased by incubation with increasing concentrations of 18-carbon fatty acids. In conclusion, our findings provided evidence that 18-carbon fatty acids (stearate, oleate and linoleate) significantly increased cytosolic TAG accumulation in a dose-dependent manner, probably by promoting lipogenic genes and proteins that regulate the channeling of fatty acids towards milk TAG synthesis in pMECs.


Asunto(s)
Ácido Linoleico/farmacología , Glándulas Mamarias Animales/citología , Ácido Oléico/farmacología , Estearatos/farmacología , Triglicéridos/biosíntesis , Animales , Técnicas de Cultivo de Célula , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Citosol/química , Relación Dosis-Respuesta a Droga , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Redes Reguladoras de Genes/efectos de los fármacos , Lipogénesis/efectos de los fármacos , Glándulas Mamarias Animales/química , Glándulas Mamarias Animales/efectos de los fármacos , Leche/química , Porcinos
13.
Trop Anim Health Prod ; 53(1): 121, 2021 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-33442786

RESUMEN

Organic trace minerals (OTMs) have the potential to replace inorganic trace minerals (ITMs), but the degree to which the dietary levels can be reduced is not well defined. This study aimed to investigate the effect of replacing of ITMs with lower levels of OTMs on growth performance, blood parameters, antioxidant status, and immune indexes in weaned piglets. The experiment was conducted in a subtropical city in Guangdong Province in South China (subtropical climate) from July to September 2018. A total of 600 pigs with an average initial BW of 8.90 kg were allotted by gender and weight to 5 treatments with 6 replicate pens per treatment. Experimental treatments: (A) Control group (a basal diet with iron, copper, manganese, and zinc from sulfates and sodium selenite providing commercially utilized levels in China of 150, 25, 40, 150, and 0.5 mg/kg, respectively). (B) 1/2 ITM group (inorganic trace minerals providing 1/2 control group levels). (C) 1/2 OTM group (1/2 control group trace mineral levels with manganese, iron, zinc, and selenium from Sel-Plex® and Cu from Bioplex®). (D) 1/3 ITM group (1/3 control group trace mineral levels from inorganic forms). (E) 1/3 OTM group (1/3 control group trace mineral levels from organic forms). The results suggest no significant effects of trace mineral sources or levels, on average daily gain (ADG) and average daily feed intake (ADFI) among different treatments during the entire experiment. The level of zinc in serum was significantly decreased in the 1/3 ITM group. The 1/3 OTM group had a significantly higher (P < 0.05) immunoglobulin G (IgG) level in serum. Fecal mineral excretion decreased significantly (P < 0.05) when decreased dietary levels of trace minerals were included at 1/2 and 1/3 levels regardless of sources. Fecal concentrations of zinc excretion were lower (P < 0.05) with 1/2 OTM supplementation than 1/2 ITMs. The present study shows that replacing high doses of ITMs with low concentrations (1/3) of OTMs does not adversely affect the growth performance of piglets. At low levels, total replacement of ITMs with OTMs improved IgG and reduced fecal excretion of copper, zinc, iron, and manganese, thereby mitigating environmental pollution.


Asunto(s)
Oligoelementos , Alimentación Animal/análisis , Animales , Antioxidantes , China , Cobre , Dieta/veterinaria , Suplementos Dietéticos , Minerales/análisis , Porcinos
14.
Nutr Res Rev ; 33(2): 287-297, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32151298

RESUMEN

The mammary gland, a unique exocrine organ, is responsible for milk synthesis in mammals. Neonatal growth and health are predominantly determined by quality and quantity of milk production. Amino acids are crucial maternal nutrients that are the building blocks for milk protein and are potential energy sources for neonates. Recent advances made regarding the mammary gland further demonstrate that some functional amino acids also regulate milk protein and fat synthesis through distinct intracellular and extracellular pathways. In the present study, we discuss recent advances in the role of amino acids (especially branched-chain amino acids, methionine, arginine and lysine) in the regulation of milk synthesis. The present review also addresses the crucial questions of how amino acids are transported, sensed and transduced in the mammary gland.


Asunto(s)
Aminoácidos/química , Grasas/química , Glándulas Mamarias Animales/fisiología , Glándulas Mamarias Humanas/fisiología , Proteínas de la Leche/química , Animales , Femenino , Humanos , Metabolismo de los Lípidos , Leche/química , Biosíntesis de Proteínas , Transducción de Señal
15.
Acta Biochim Biophys Sin (Shanghai) ; 52(2): 133-140, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-31942919

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is an important etiology of pneumonia. Interleukin (IL)-9 is a T helper 9 (Th9) cytokine and participates in the pathogenesis of infectious diseases. Here, we investigated the role of IL-9 by using an MRSA pneumonia animal model. The BALB/c mice underwent nasal inhalation with an ST239 MRSA strain to establish the mouse model of MRSA pneumonia, and a subset of mice were intravenously injected with IL-9 neutralizing antibody or immunoglobulin (Ig) G. At 3 and 8 days postinfection, the peripheral blood, bronchioalveolar lavage fluid (BALF), and lung tissues were collected. The frequencies of Th9 cells and the levels of cytokines in peripheral blood, BALF, and lung tissues were determined by flow cytometry and enzyme-linked immunosorbent assay (ELISA), respectively. The colony counts of MRSA in BALF and lung tissue were detected. The lung pathological changes were examined using hematoxylin and eosin staining. Data from flow cytometry, qRT-PCR, and ELISA showed that MRSA-infected mice exhibited higher frequency of Th9 cells and higher IL-9 mRNA and protein levels in the peripheral blood, BALF, and lung tissues of mice. In contrast, the neutralization of IL-9 abrogated MRSA inoculation-induced Th9 cell generation and IL-9 production in BALF and lung tissues. Furthermore, bacterial counting and histological examination showed that the numbers of bacteria in BALF and lungs and the lung pathological scores induced by MRSA inoculation were attenuated by the neutralization of IL-9. Moreover, cell counting and ELISA results demonstrated that IL-9 neutralization diminished the MRSA inoculation-induced count of neutrophils and macrophages and levels of pro-inflammatory cytokines in BALF. Collectively, IL-9 neutralization attenuated inflammation of MRSA pneumonia by regulating Th9/IL-9 expression.


Asunto(s)
Inflamación/prevención & control , Interleucina-9/metabolismo , Staphylococcus aureus Resistente a Meticilina , Neumonía/microbiología , Animales , Anticuerpos/farmacología , Líquido del Lavado Bronquioalveolar/microbiología , Recuento de Colonia Microbiana , Citocinas/metabolismo , Modelos Animales de Enfermedad , Interleucina-9/antagonistas & inhibidores , Interleucina-9/genética , Interleucina-9/inmunología , Pulmón/microbiología , Ratones , Ratones Endogámicos BALB C , Neumonía/patología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/patología
16.
J Integr Neurosci ; 19(4): 595-600, 2020 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-33378834

RESUMEN

Phosphorus-31 nuclear-spin entanglements within Ca9(PO4)6 molecules (Posner molecules) have been proposed to be central for neural processing. However, this has yet to be proven experimentally. Relatedly, increasing calcium ion concentration in the cerebrospinal fluid has been proposed to enhance consciousness by accelerating Posner molecules' creation. A dependence on calcium isotope is also expected. Here we test these predictions experimentally by measuring the loss of righting reflex ED50 for mice to sevoflurane - an increase in loss of righting reflex ED50 indicates a higher level of consciousness and vice versa. Our mice's findings demonstrate that intracerebroventricular injection of EGTA enhances the sevoflurane-induced loss of righting reflex ED50 while injecting calcium-40 chloride or calcium-43 chloride causes an opposite effect. Further, the identical effects of calcium-40 and calcium-43 indicate an absence of calcium isotope dependence. Here, our findings disprove conventional proposals that calcium ion concentration correlates with consciousness.


Asunto(s)
Anestesia , Fosfatos de Calcio/química , Estado de Conciencia/fisiología , Fósforo/química , Teoría Cuántica , Anestésicos por Inhalación/farmacología , Animales , Conducta Animal/fisiología , Isótopos de Calcio , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos Biológicos , Sevoflurano/farmacología
17.
J Therm Biol ; 94: 102751, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33292992

RESUMEN

The medicinal plant Artemisia annua L. is well known for its antimalarial compound artemisinin and the antioxidant capacity of its active ingredients. However, low bioavailability of Artemisia annua L. limits its therapeutic potential, fermentation of Artemisia annua L. can improve its bioavailability. This study was aimed to investigate the effects of dietary supplementation of enzymatically-treated Artemisia annua L. (EA) on reproductive performance, antioxidant status, milk composition of heat-stressed sows and intestinal barrier integrity of their preweaning offspring. 135 multiparous sows of average parity 4.65 (Landrace × large white) at day 85 of pregnancy were randomly distributed into 3 treatments. Sows in the control group were housed at control rooms (temperature: 27.12 ± 0.18 °C, temperature-humidity index (THI): 70.90 ± 0.80) and fed the basal diet. Sows in the HS, HS + EA groups were fed the basal diet supplemented with 0 or 1.0 g/kg EA respectively, and reared at heat stress rooms (temperature: 30.11 ± 0.16 °C, THI: 72.70 ± 0.60). Heat stress increased the malondialdehyde (MDA) content, reduced the activities of total antioxidant capacity (T-AOC) and total superoxide dismutase (T-SOD) of sows and piglets, and seriously compromised the antioxidant capacity of the sows and the intestinal integrity of their offspring. However, dietary supplementation of 1.0 g/kg EA reduced the MDA content, increased the activities of T-SOD and T-AOC in serum, colostrum, and milk of heat-stressed sows, and increased colostrum yield and 14-d milk fat content. EA supplementation also increased piglet weaning weight and the activities of T-SOD and T-AOC in serum. In addition, the abundances of intestinal tight junction proteins claudin-1 and occludin were up-regulated in piglets in EA-supplemented group. In conclusion, dietary EA supplementation at 1.0 g/kg can alleviate the oxidative stress in heat-stressed sows, improve the antioxidant capacity in both sows and their offspring, and promote the intestinal barrier integrity in their offspring. EA may be a potent dietary supplement that ameliorates oxidative stress in livestock production by improving the antioxidant capacity.


Asunto(s)
Artemisia annua , Suplementos Dietéticos , Calor/efectos adversos , Estrés Oxidativo , Reproducción , Alimentación Animal , Animales , Artemisia annua/química , Celulasa/química , Dieta/veterinaria , Femenino , Glutatión/sangre , Trastornos de Estrés por Calor/sangre , Trastornos de Estrés por Calor/genética , Trastornos de Estrés por Calor/veterinaria , Leche/química , Oxidorreductasas/sangre , Poligalacturonasa/química , Embarazo , Porcinos/sangre , Porcinos/genética , Enfermedades de los Porcinos/sangre , Enfermedades de los Porcinos/genética , Proteínas de Uniones Estrechas/genética
18.
IUBMB Life ; 71(7): 1021-1029, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31018046

RESUMEN

Melatonin is one of the main hormones that regulate biological rhythms and have immunomodulation, anti-inflammatory, and antioxidation functions. In this study, we aimed to explore the effect of melatonin on the autophagy, apoptosis, and inflammatory reaction of macrophages (RAW264.7 cells) stimulated by nanosilica. SiO2 (100 mg/mL, 10-20 nm) was used to stimulate RAW264.7 cells at different time points (0, 2, 4, 8, 12, and 24 hr). Melatonin (200 µM) was added to SiO2 -stimulated macrophages at 12 hr. Beclin-1, LC3, Bax, Bcl-2, and Caspase-3 were examined with western blotting. Flow cytometry was used to detect apoptosis. The levels of TNF-α, IL-1ß, and IL-18 were detected by ELISA. The level of TNF-α in the supernatant of SiO2 -stimulated cells gradually increased with time but decreased following melatonin administration. In contrast, the expression of IL-1ß and IL-18 increased after melatonin treatment. LC3 and Bax signaling pathways were activated in SiO2 -stimulated RAW264.7 cells, showing elevated expression of LC3 and reduced expression of Bax in the melatonin-treated cells. GFP-LC3 puncta were significantly increased in SiO2 -stimulated RAW264.7 cells and decreased in melatonin-treated cells. The apoptotic rate in SiO2 -stimulated RAW264.7 cells increased with time and decreased after melatonin treatment, and the number of phagosomes increased with the stimulation of nanosilica and the treatment of melatonin. Melatonin might promote autophagy and inhibit apoptosis as well as inflammatory responses of RAW264.7 cells stimulated by nanosilica. © 2019 IUBMB Life, 2019.


Asunto(s)
Antioxidantes/farmacología , Apoptosis , Autofagia , Macrófagos/patología , Melatonina/farmacología , Nanopartículas/química , Dióxido de Silicio/farmacología , Animales , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Fagosomas/efectos de los fármacos , Fagosomas/metabolismo , Células RAW 264.7 , Transducción de Señal
19.
Anesthesiology ; 129(2): 271-277, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29642079

RESUMEN

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: Xenon is an elemental anesthetic with nine stable isotopes. Nuclear spin is a quantum property which may differ among isotopes. Xenon 131 (Xe) has nuclear spin of 3/2, xenon 129 (Xe) a nuclear spin of 1/2, and the other seven isotopes have no nuclear spin. This study was aimed to explore the effect of nuclear spin on xenon anesthetic potency. METHODS: Eighty C57BL/6 male mice (7 weeks old) were randomly divided into four groups, xenon 132 (Xe), xenon 134 (Xe), Xe, and Xe groups. Due to xenon's low potency, loss of righting reflex ED50 for mice to xenon was determined with 0.50% isoflurane. Loss of righting reflex ED50 of isoflurane was also measured, and the loss of righting reflex ED50 values of the four xenon isotopes were then calculated. The exact polarizabilities of the isotopes were calculated. RESULTS: Combined with 0.50% isoflurane, the loss of righting reflex ED50 values were 15 ± 4%, 16 ± 5%, 22 ± 5%, and 23 ± 7% for Xe, Xe, Xe, and Xe, respectively. For xenon alone, the loss of righting reflex ED50 values of Xe, Xe, Xe, and Xe were 70 ± 4%, 72 ± 5%, 99 ± 5%, and 105 ± 7%, respectively. Four isotopes had a same exact polarizability of 3.60 Å. CONCLUSIONS: Xenon isotopes with nuclear spin are less potent than those without, and polarizability cannot account for the difference. The lower anesthetic potency of Xe may be the result of it participating in conscious processing and therefore partially antagonizing its own anesthetic potency. Nuclear spin is a quantum property, and our results are consistent with theories that implicate quantum mechanisms in consciousness.


Asunto(s)
Anestésicos por Inhalación/administración & dosificación , Estado de Conciencia/efectos de los fármacos , Isoflurano/administración & dosificación , Reflejo de Enderezamiento/efectos de los fármacos , Isótopos de Xenón/administración & dosificación , Animales , Estado de Conciencia/fisiología , Relación Dosis-Respuesta a Droga , Masculino , Ratones , Ratones Endogámicos C57BL , Reflejo de Enderezamiento/fisiología
20.
Arch Anim Nutr ; 72(4): 261-274, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29812957

RESUMEN

Recent studies have shown that L-carnitine supplementation of sows during pregnancy and lactation enhances their reproductive performance, but the underlying mechanisms are still needed to be further confirmed. This study was conducted to investigate the function of L-carnitine on placental development, milk nutrient content and release of hormones in sows. In this experiment, 40 multiparous crossbred sows (Yorkshire × Landrace) were allotted to two groups fed diets with or without a supplemental 50 mg/kg L-carnitine. The experimental diets were fed from d 1 post-coitus until d 21 post-partum. L-carnitine-treated sow had fewer weak piglets (p < 0.05) and a greater percentage of oestrus by 5 after 5-d post-partum (p < 0.05) than control sows. The percentage fat from colostrum was greater in L-carnitine-treated sow than control sows (p < 0.05). L-carnitine-treated sows had greater plasma concentrations of triglyceride and insulin-like growth factor (IGF)-1 and lesser plasma concentrations of glucose and IGF-binding protein (IGFBP-3) on day 60 of pregnancy (p < 0.05). A clearer structure of chorions, better-developed capillaries and absence of necrosis were observed in L-carnitine-treated sows compared with control sows. The protein abundance of IGF-1 and IGF-2 in placental chorions was greater in L-carnitine-treated sows compared with control sows (p < 0.05). This study suggests that sows fed an L-carnitine supplemented diet during pregnancy improved reproductive performance through enhancement of placental development and by increasing IGF concentrations in blood plasma and placental chorions.


Asunto(s)
Carnitina/metabolismo , Corion/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Leche/química , Placentación/efectos de los fármacos , Reproducción/efectos de los fármacos , Porcinos/fisiología , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Carnitina/administración & dosificación , Corion/química , Dieta/veterinaria , Suplementos Dietéticos/análisis , Femenino , Leche/efectos de los fármacos , Embarazo
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