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1.
Sensors (Basel) ; 24(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39066051

RESUMO

With the popularity of smartphones, a large number of "phubbers" have emerged who are engrossed in their phones regardless of the situation. In response to the potential dangers that phubbers face while traveling, this paper proposes a multimodal danger perception network model and early warning system for phubbers, designed for mobile devices. This proposed model consists of surrounding environment feature extraction, user behavior feature extraction, and multimodal feature fusion and recognition modules. The environmental feature module utilizes MobileNet as the backbone network to extract environmental description features from the rear-view image of the mobile phone. The behavior feature module uses acceleration time series as observation data, maps the acceleration observation data to a two-dimensional image space through GADFs (Gramian Angular Difference Fields), and extracts behavior description features through MobileNet, while utilizing statistical feature vectors to enhance the representation capability of behavioral features. Finally, in the recognition module, the environmental and behavioral characteristics are fused to output the type of hazardous state. Experiments indicate that the accuracy of the proposed model surpasses existing methods, and it possesses the advantages of compact model size (28.36 Mb) and fast execution speed (0.08 s), making it more suitable for deployment on mobile devices. Moreover, the developed image-acceleration multimodal phubber hazard recognition network combines the behavior of mobile phone users with surrounding environmental information, effectively identifying potential hazards for phubbers.

2.
Amino Acids ; 48(9): 2131-44, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27156063

RESUMO

Branched-chain amino acids (BCAA), including leucine (Leu), isoleucine (Ile), and valine (Val), play critical roles in energy homeostasis and lipid metabolism in addition to their other functions, such as in protein metabolism. This study investigated the effects of different dietary BCAA ratios on the intramuscular fat (IMF) content and fatty acid composition in different location of skeletal muscles, including the longissimus dorsi (LD), biceps femoris (BF), and psoas major (PM) muscles of growing pigs, and also examined the mRNA expression levels of genes involved in lipid metabolism in these muscle tissues. The experiment was performed on 40 growing pigs (Large White × Landrace) with a similar initial weight (9.85 ± 0.35 kg). The pigs were randomly assigned to one of five diets: diet A was a positive control and contained 20 % crude protein (CP) with a Leu:Ile:Val ratio of 1:0.51:0.63 according to the recommendation of the National Research Council (NRC); for diets B to E, the CP level was reduced to 17 %, and the Leu:Ile:Val ratios were 1:1:1, 1:0.75:0.75, 1:0.51:0.63, and 1:0.25:0.25, respectively. No significant difference was observed in the average feed intake and feed efficiency of the pigs fed the low protein diet (17 % CP) with BCAA treatments relative to the positive control. However, there was a tendency for increased feed efficiency of the 1:0.75:0.75 group compared with the 1:1:1 group (P = 0.09). The BCAA ratio of 1:0.75:0.75 (17 % CP) increased the IMF content of BF muscle (P < 0.01). Moreover, varied dietary BCAA supplementation with a reduced protein level had different effects on the fatty acid composition of the LD, BF, and PM muscles. The BCAA ratio of 1:0.51:0.63-1:0.75:0.75 (17 % CP) significantly lowered the ratio of n-6 to n-3 polyunsaturated fatty acid in these muscles compared with the positive control group (20 % CP). This effect was associated with an increase in mRNA expression levels of acetyl-CoA carboxylase, lipoprotein lipase, fatty acid transport protein, and fatty acid binding protein 4 in the muscles (P < 0.05). The results indicated that the reduced protein diet (17 % CP) with the BCAA ratio within 1:0.25:0.25-1:0.75:0.75 could increase the IMF content in BF muscle and significantly improve the fatty acid composition in different skeletal muscles accompanied by changes in the expression of genes involved in lipid metabolism, compared with those in the pigs that received adequate dietary protein (20 %), which might result in improved eating quality and nutritional value of the meat.


Assuntos
Aminoácidos de Cadeia Ramificada/farmacologia , Proteínas Alimentares/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Proteínas Musculares/biossíntese , Músculo Esquelético/metabolismo , Suínos/crescimento & desenvolvimento , Animais
3.
Metabolism ; 157: 155933, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38729601

RESUMO

AIMS/HYPOTHESIS: cGAS (cyclic GMP-AMP synthase) has been implicated in various cellular processes, but its role in ß-cell proliferation and diabetes is not fully understood. This study investigates the impact of cGAS on ß-cell proliferation, particularly in the context of diabetes. METHODS: Utilizing mouse models, including cGAS and STING (stimulator of interferon genes) knockout mice, we explored the role of cGAS in ß-cell function. This involved ß-cell-specific cGAS knockout (cGASßKO) mice, created by breeding cGAS floxed mice with transgenic mice expressing Cre recombinase under the insulin II promoter. We analyzed cGAS expression in diabetic mouse models, evaluated the effects of cGAS deficiency on glucose tolerance, and investigated the molecular mechanisms underlying these effects through RNA sequencing. RESULTS: cGAS expression is upregulated in the islets of diabetic mice and by high glucose treatment in MIN6 cells. Both global cGAS deficiency and ß-cell-specific cGAS knockout mice lead to improved glucose tolerance by promoting ß-cell mass. Interestingly, STING knockout did not affect pancreatic ß-cell mass, suggesting a STING-independent mechanism for cGAS's role in ß-cells. Further analyses revealed that cGAS- but not STING-deficiency leads to reduced expression of CEBPß, a known suppressor of ß-cell proliferation, concurrently with increased ß-cell proliferation. Moreover, overexpression of CEBPß reverses the upregulation of Cyclin D1 and D2 induced by cGAS deficiency, thereby regulating ß-cell proliferation. These results confirm that cGAS regulation of ß-cell proliferation via a CEBPß-dependent but STING-independent mechanism. CONCLUSIONS/INTERPRETATION: Our findings highlight the pivotal role of cGAS in promoting ß-cell proliferation and maintaining glucose homeostasis, potentially by regulating CEBPß expression in a STING-independent manner. This study uncovers the significance of cGAS in controlling ß-cell mass and identifies a potential therapeutic target for enhancing ß-cell proliferation in the treatment of diabetes.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT , Proliferação de Células , Células Secretoras de Insulina , Proteínas de Membrana , Camundongos Knockout , Nucleotidiltransferases , Animais , Células Secretoras de Insulina/metabolismo , Nucleotidiltransferases/metabolismo , Nucleotidiltransferases/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proliferação de Células/fisiologia , Camundongos , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Masculino , Camundongos Endogâmicos C57BL
4.
Sci Adv ; 8(38): eabq1799, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36129988

RESUMO

Pancreatic ß cell failure is a hallmark of diabetes. However, the causes of ß cell failure remain incomplete. Here, we report the identification of tetranectin (TN), an adipose tissue-enriched secretory molecule, as a negative regulator of insulin secretion in ß cells in diabetes. TN expression is stimulated by high glucose in adipocytes via the p38 MAPK/TXNIP/thioredoxin/OCT4 signaling pathway, and elevated serum TN levels are associated with diabetes. TN treatment greatly exacerbates hyperglycemia in mice and suppresses glucose-stimulated insulin secretion in islets. Conversely, knockout of TN or neutralization of TN function notably improves insulin secretion and glucose tolerance in high-fat diet-fed mice. Mechanistically, TN binds with high selectivity to ß cells and inhibits insulin secretion by blocking L-type Ca2+ channels. Our study uncovers an adipocyte-ß cell cross-talk that contributes to ß cell dysfunction in diabetes and suggests that neutralization of TN levels may provide a new treatment strategy for type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Adipócitos/metabolismo , Animais , Glucose/metabolismo , Insulina/metabolismo , Secreção de Insulina , Lectinas Tipo C , Camundongos , Tiorredoxinas , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Nat Commun ; 12(1): 326, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436607

RESUMO

Adipose tissue-resident T cells have been recognized as a critical regulator of thermogenesis and energy expenditure, yet the underlying mechanisms remain unclear. Here, we show that high-fat diet (HFD) feeding greatly suppresses the expression of disulfide-bond A oxidoreductase-like protein (DsbA-L), a mitochondria-localized chaperone protein, in adipose-resident T cells, which correlates with reduced T cell mitochondrial function. T cell-specific knockout of DsbA-L enhances diet-induced thermogenesis in brown adipose tissue (BAT) and protects mice from HFD-induced obesity, hepatosteatosis, and insulin resistance. Mechanistically, DsbA-L deficiency in T cells reduces IFN-γ production and activates protein kinase A by reducing phosphodiesterase-4D expression, leading to increased BAT thermogenesis. Taken together, our study uncovers a mechanism by which T cells communicate with brown adipocytes to regulate BAT thermogenesis and whole-body energy homeostasis. Our findings highlight a therapeutic potential of targeting T cells for the treatment of over nutrition-induced obesity and its associated metabolic diseases.


Assuntos
Dieta Hiperlipídica , Glutationa Transferase/deficiência , Interferon gama/biossíntese , Linfócitos T/metabolismo , Termogênese , Adipócitos Marrons/efeitos dos fármacos , Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Animais , Regulação para Baixo/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Comportamento Alimentar , Glutationa Transferase/metabolismo , Resistência à Insulina , Interferon gama/administração & dosagem , Interferon gama/farmacologia , Masculino , Camundongos Knockout , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Obesidade/genética , Obesidade/patologia , Linfócitos T/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/metabolismo , Termogênese/efeitos dos fármacos , Termogênese/genética , Proteína Desacopladora 1/metabolismo
6.
Metabolism ; 123: 154863, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34375645

RESUMO

Reduced ß-cell mass and impaired ß-cell function are primary causes of all types of diabetes. However, the intrinsic molecular mechanism that regulates ß-cell growth and function remains elusive. Here, we demonstrate that the small GTPase Rheb1 is a critical regulator of glucose-stimulated insulin secretion (GSIS) in ß-cells. Rheb1 was highly expressed in mouse and human islets. In addition, ß-cell-specific knockout of Rheb1 reduced the ß-cell size and mass by suppressing ß-cell proliferation and increasing ß-cell apoptosis. However, tamoxifen-induced deletion of Rheb1 in ß-cells had no significant effect on ß-cell mass and size but significantly impaired GSIS. Rheb1 facilitates GSIS in human or mouse islets by upregulating GLUT1 or GLUT2 expression, respectively, in a mTORC1 signaling pathway-dependent manner. Our findings reveal a critical role of Rheb1 in regulating GSIS in ß-cells and identified a new target for the therapeutic treatment of diabetes mellitus.


Assuntos
Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Células Secretoras de Insulina/metabolismo , Regulação para Cima , Proteínas ras/fisiologia , Animais , Proliferação de Células , Humanos , Camundongos , Transdução de Sinais , Proteínas ras/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-29423216

RESUMO

BACKGROUND: Pregnancy is associated with important changes in gut microbiota composition. Dietary factors may affect the diversity, composition, and metabolic activity of the intestinal microbiota. Among amino acids, proline is known to play important roles in protein metabolism and structure, cell differentiation, conceptus growth and development, and gut microbiota re-equilibration in case of dysbiosis. RESULTS: Dietary supplementation with 1% proline decreased (P < 0.05) the amounts of Klebsiella pneumoniae, Peptostreptococcus productus, Pseudomonas, and Veillonella spp. in distal colonic contents than that in the control group. The colonic contents of Butyrivibrio fibrisolvens, Bifidobacterium sp., Clostridium coccoides, Clostridium coccoides-Eubacterium rectale, Clostridium leptum subgroup, Escherichia coli, Faecalibacterium prausnitzii, Fusobacterium prausnitzii, and Prevotella increased (P < 0.05) on d 70 of pregnancy as compared with those on d 45 of pregnancy. The colonic concentrations of acetate, total straight-chain fatty acid, and total short-chain fatty acids (SCFA) in the proline-supplemented group were lower (P < 0.05), and butyrate level (P = 0.06) decreased as compared with the control group. Almost all of the SCFA displayed higher (P < 0.05) concentrations in proximal colonic contents on d 70 of pregnancy than those on d 45 of pregnancy. The concentrations of 1,7-heptyl diamine (P = 0.09) and phenylethylamine (P < 0.05) in proximal colonic contents were higher, while those of spermidine (P = 0.05) and total bioamine (P = 0.06) tended to be lower in the proline-supplemented group than those in the control group. The concentrations of spermidine, spermine, and total bioamine in colonic contents were higher (P < 0.05) on d 70 of pregnancy than those measured on d 45 of pregnancy. In contrast, the concentration of phenylethylamine was lower (P < 0.05) on d 70 than on d 45 of pregnancy. CONCLUSION: These findings indicate that L-proline supplementation modifies both the colonic microbiota composition and the luminal concentrations of several bacterial metabolites. Furthermore, our data show that both the microbiota composition and the concentrations of bacterial metabolites are evolving in the course of pregnancy. These results are discussed in terms of possible implication in terms of luminal environment and consequences for gut physiology and health.

8.
PLoS One ; 12(2): e0172086, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28196137

RESUMO

The mammalian gut microbiota influences various metabolic and physiological processes. Substantial metabolic changes occur during a healthy pregnancy that may be related to microbiota composition dynamics. However, the effect of diet on intestinal microbiota composition and diversity during pregnancy remains unclear. We examined the ileal contents of Huanjiang mini-pigs at two pregnancy stages to determine the effects of dietary nutrient levels on such microbial communities. Animals received either a higher-nutrient (HN) diet formulated to meet US National Research Council requirements or a lower-nutrient (LN) diet that met the Chinese National Feeding Standard recommendations. On day 45 or 75 of pregnancy, sows were euthanized and their ileal contents sampled. Experimental diet and pregnancy stage did not affect ileal bacterial richness or diversity, as determined by Chao1 and ACE species richness measures and Shannon and Simpson indices, respectively. The phyla Firmicutes and Proteobacteria, accounting for 69.99-85.44% and 5.82-15.17% of the total reads, respectively, predominated regardless of diet. At the genus level, diet significantly affected the abundance of Lactobacillus species, which was greater in pigs given HN feed (P < 0.05), but had little impact on that of Megasphaera species (P = 0.096). Pregnancy stage had a minimal effect on Proteobacteria numbers (P = 0.053). The number of bacteria of the phylum Firmicutes and genus Lactobacillus decreased, while that of the phylum Proteobacteria, family Enterobacteriaceae, and genus Bacteroides increased between days 45 and 75 of pregnancy. Of the short-chain fatty acids (SCFAs) measured, only propionate levels changed significantly, with higher concentrations observed on day 45 than on day 75. Our findings indicate that Firmicutes and Proteobacteria dominate pregnant sow ileal bacterial profiles. Excepting a tendency for the number of Proteobacteria to increase as pregnancy progressed, pregnancy stage and diet had little effect on ileal microbiotic composition and diversity and luminal SCFA concentrations.


Assuntos
Ração Animal , Bactérias/crescimento & desenvolvimento , Microbioma Gastrointestinal/fisiologia , Íleo/microbiologia , Gravidez/fisiologia , Porco Miniatura/microbiologia , Suínos/microbiologia , Animais , Bactérias/classificação , Feminino , Fatores de Tempo
9.
Nutrition ; 36: 8-16, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28336113

RESUMO

OBJECTIVES: Branched-chain amino acids (BCAAs), including leucine (Leu), isoleucine (Ile), and valine (Val), are key regulators of protein synthesis in muscle. The aim of this study was to investigate the effect of different BCAA ratios (Leu:Ile:Val) on the proliferation, differentiation, and expression levels of the regulators related to protein metabolism of C2 C12 myocytes. METHODS: Studies were conducted in C2C12 myocytes exposed to different BCAA ratios (Leu: Ile: Val = 0, 1:0.25:0.25, 1:1:1). RESULTS: The ratio of 1:0.25:0.25 increased cell viability and promoted cell cycle progression from G0/G1 phase to S phase, which was an indicator of proliferation enhancement (P < 0.05). Moreover, this optimal ratio (1:0.25:0.25) promoted the differentiation of myocytes into myotubes by upregulating myogenin and interleukin-15 gene expression, and differently regulated the expression of L-type amino acid transporter 1 and 4 and system ASC amino acid transporters 2. Furthermore, the ratio stimulated mTOR expression at the mRNA and phosphorylated protein levels, as well as ribosomal protein S6 kinase and regulatory-associated protein of mTOR (raptor). In contrast, the optimal ratio decreased the amount of ubiquitin ligase muscle-specific RING finger 1 and muscle atrophy F-box during proliferation and differentiation (P < 0.05). No change was observed in the expression of key genes related to energy metabolism except for uncoupling protein 3 (P > 0.05). CONCLUSIONS: The results suggested that appropriate BCAA ratios could enhance proliferation and differentiation of the C2 C12 myocytes, also mediate the key regulators related to protein metabolism including the mTORC1 pathway. A proper utilization of balanced BCAA ratio in food would be beneficial to human and animal nutrition.


Assuntos
Aminoácidos de Cadeia Ramificada/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Musculares/efeitos dos fármacos , Biossíntese de Proteínas , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Células Musculares/metabolismo , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Ligases SKP Culina F-Box/genética , Proteínas Ligases SKP Culina F-Box/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteína Desacopladora 3/genética , Proteína Desacopladora 3/metabolismo , Regulação para Cima
10.
Sci Rep ; 6: 37224, 2016 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-27917879

RESUMO

The gut harbours diverse and complex microbiota, which influence body health including nutrient metabolism, immune development, and protection from pathogens. Pregnancy is associated with immune and metabolic changes that might be related to microbiota compositional dynamics. We therefore investigated the colonic luminal bacteria community in Huanjiang mini-pigs fed diets with different nutrient levels from the first to third trimester of pregnancy. The concentrations of intestinal metabolites including short-chain fat acids, NH3-N, indole, skatole, and bioamines were also determined. We found that the colonic bacteria species richness estimators (Chao1 and ACE) decreased with increased gestational age. The dominant phyla identified were Firmicutes and Bacteroidetes; the dominant genera were Lactobacillus, Treponema, Ruminococcus, Clostridium, and Prevotella. In addition, microbiota displayed spatial and temporal heterogeneity in composition, diversity, and species abundance in different colonic segments from the first to third trimester of pregnancy. Furthermore, the bacterial metabolites also changed according to the diet used and the pregnancy stage. These findings suggest that colonic bacteria richness decreased as gestational age increased, and that the higher nutrient level diet increased the production of metabolites related to nitrogen metabolism. However, although the higher nutrient diet was associated with pregnancy syndrome, causal links remain to be determined.


Assuntos
Ração Animal , Colo/microbiologia , Microbioma Gastrointestinal , Animais , Aminas Biogênicas/metabolismo , Ácidos Graxos Voláteis/metabolismo , Feminino , Microbioma Gastrointestinal/genética , Indóis/metabolismo , Nitrogênio/metabolismo , Gravidez , Escatol/metabolismo , Suínos , Porco Miniatura
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