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1.
Genes (Basel) ; 10(8)2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398921

RESUMO

A dose of proanthocyanidins with satiating properties proved to be able to limit body weight increase several weeks after administration under exposure to a cafeteria diet. Here we describe some of the molecular targets and the duration of the effects. We treated rats with 500 mg grape seed proanthocyanidin extract (GSPE)/kg BW for ten days. Seven or seventeen weeks after the last GSPE dose, while animals were on a cafeteria diet, we used reverse transcriptase-polymerase chain reaction (RT-PCR) to measure the mRNA of the key energy metabolism enzymes from the liver, adipose depots and muscle. We found that a reduction in the expression of adipose Lpl might explain the lower amount of adipose tissue in rats seven weeks after the last GSPE dose. The liver showed increased expression of Cpt1a and Hmgs2 together with a reduction in Fasn and Dgat2. In addition, muscle showed a higher fatty oxidation (Oxct1 and Cpt1b mRNA). However, after seventeen weeks, there was a completely different gene expression pattern. At the conclusion of the study, seven weeks after the last GSPE administration there was a limitation in adipose accrual that might be mediated by an inhibition of the gene expression of the adipose tissue Lpl. Concomitantly there was an increase in fatty acid oxidation in liver and muscle.


Assuntos
Adiposidade/efeitos dos fármacos , Depressores do Apetite/farmacologia , Dieta da Carga de Carboidratos/efeitos adversos , Dieta Ocidental/efeitos adversos , Sobrepeso/prevenção & controle , Proantocianidinas/farmacologia , Tecido Adiposo/metabolismo , Animais , Depressores do Apetite/uso terapêutico , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/metabolismo , Coenzima A-Transferases/genética , Coenzima A-Transferases/metabolismo , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Feminino , Leptina/genética , Leptina/metabolismo , Fígado/metabolismo , Músculo Esquelético/metabolismo , Sobrepeso/tratamento farmacológico , Proantocianidinas/uso terapêutico , Ratos , Vitis/química
2.
Anim Reprod Sci ; 208: 106104, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31405453

RESUMO

The peri-calving period is characterized by a negative energy balance, which leads to lipid mobilization. Thus, during this period, the liver has important functions related to optimizing milk yield, preventing metabolic and infectious diseases, and improving fertility. To clarify the relationship between liver fatty acid metabolism and reproductive performance, the present study was conducted to assess the abundance of specific hepatic proteins related to lipid metabolism in both plasma and follicular fluid in dairy cattle with different days to conception (DC). Sixteen animals were grouped according to DC, as more and fewer DC (MDC and FDC, respectively). Blood and liver biopsies were sampled 14 days before the expected calving date and 4, 14 and 28 days after calving. The plasma beta-hydroxybutyric acid (BHBA) concentrations and the liver triacylglycerol (TAG) content were greater in the MDC group (P <  0.05), whereas the protein abundance of carnitine palmitoyl transferase 1 was greater in the FDC group (P < 0.05). Additionally, total bilirubin (TBil) concentration was less in the FDC than MDC group on day 28 (P < 0.05). These results indicate lipid mobilization and liver fatty acid oxidation capacity in dairy cows could contribute to the adaptations and reproductive performance.


Assuntos
Bovinos/fisiologia , Ácidos Graxos/metabolismo , Fígado/metabolismo , Reprodução/fisiologia , Acil-CoA Oxidase/genética , Acil-CoA Oxidase/metabolismo , Ração Animal , Criação de Animais Domésticos , Animais , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/metabolismo , Bovinos/sangue , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Feminino , Regulação da Expressão Gênica , Metabolismo dos Lipídeos , PPAR alfa/genética , PPAR alfa/metabolismo , Período Periparto/sangue , Período Periparto/fisiologia , Gravidez , Triglicerídeos/metabolismo
3.
J Dairy Sci ; 102(9): 8159-8174, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301836

RESUMO

We performed genome-wide association analyses for milk, fat, and protein yields and somatic cell score based on lactation stages in the first 3 parities of Canadian Ayrshire, Holstein, and Jersey cattle. The genome-wide association analyses were performed considering 3 different lactation stages for each trait and parity: from 5 to 95, from 96 to 215, and from 216 to 305 d in milk. Effects of single nucleotide polymorphisms (SNP) for each lactation stage, trait, parity, and breed were estimated by back-solving the direct breeding values estimated using the genomic best linear unbiased predictor and single-trait random regression test-day models containing only the fixed population average curve and the random genomic curves. To identify important genomic regions related to the analyzed lactation stages, traits, parities and breeds, moving windows (SNP-by-SNP) of 20 adjacent SNP explaining more than 0.30% of total genetic variance were selected for further analyses of candidate genes. A lower number of genomic windows with a relatively higher proportion of the explained genetic variance was found in the Holstein breed compared with the Ayrshire and Jersey breeds. Genomic regions associated with the analyzed traits were located on 12, 8, and 15 chromosomes for the Ayrshire, Holstein, and Jersey breeds, respectively. Especially for the Holstein breed, many of the identified candidate genes supported previous reports in the literature. However, well-known genes with major effects on milk production traits (e.g., diacylglycerol O-acyltransferase 1) showed contrasting results among lactation stages, traits, and parities of different breeds. Therefore, our results suggest evidence of differential sets of candidate genes underlying the phenotypic expression of the analyzed traits across breeds, parities, and lactation stages. Further functional studies are needed to validate our findings in independent populations.


Assuntos
Bovinos/genética , Estudo de Associação Genômica Ampla/veterinária , Genoma/genética , Lactação/genética , Leite/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Animais , Cruzamento , Bovinos/fisiologia , Diacilglicerol O-Aciltransferase/genética , Feminino , Paridade , Fenótipo , Gravidez
4.
J Dairy Sci ; 102(8): 6842-6852, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31178185

RESUMO

In the present study, we aimed to investigate the changes in triacylglycerol (TAG) composition as affected by alterations in the cows' diet due to seasonal variations and genetic factors. For this study, 50 milk fat samples in winter and 50 in summer were used from 25 cows with the DGAT1 KK genotype and 25 cows with the DGAT1 AA genotype. The samples were analyzed for milk fat content (%), fat composition, and TAG composition. We found that the content of TAG species CN54 was higher and that of CN34 and CN36 lower in summer than in winter. This seasonal variation in TAG profile was related to seasonal changes in the fatty acids C14:0, C16:0, C18:0, C18:1 cis-9, total unsaturated fatty acids, and total long-chain fatty acids, most likely resulting from dietary differences between seasons. Furthermore, we quantified the effect of DGAT1 K232A polymorphism on TAG profile and detected a significant effect on TAG species CN36, with higher values for the DGAT1 KK genotype. When adjusting for differences in fat content, we found no significant effects of the DGAT1 K232A polymorphism on TAG profile. We detected a significant interaction between DGAT1 K232A polymorphism and season for TAG species CN42 and CN52; in summer, the KK genotype was associated with higher levels for CN42 than the AA genotype, whereas in winter, the difference between the genotypes was small. For CN52, in summer the AA genotype was associated with higher levels than the KK genotype. In winter, the difference between the genotypes was also small. We show that, regardless of preference for DGAT1 genotype (AA or KK) and depending on the availability of FA according to season, UFA (C18:1 cis-9), short-chain FA (C6:0 and C10:0), and medium-chain FA might be esterified on the glycerol backbone of the TAG, keeping the structure characteristics of each TAG species. To our knowledge, this is the first report on the interaction effect of DGAT1 K232A polymorphism and season on the TAG composition in milk fat.


Assuntos
Bovinos/genética , Diacilglicerol O-Aciltransferase/genética , Dieta/veterinária , Genótipo , Leite/química , Triglicerídeos/análise , Animais , Bovinos/fisiologia , Ácidos Graxos/análise , Ácidos Graxos Insaturados/análise , Feminino , Polimorfismo Genético/genética , Estações do Ano
5.
J Dairy Sci ; 102(8): 7536-7547, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31178189

RESUMO

High blood concentrations of nonesterified fatty acids (NEFA) and altered lipid metabolism are key characteristics of fatty liver in dairy cows. In nonruminants, the mitochondrial membrane protein mitofusin 2 (MFN2) plays important roles in regulating mitochondrial function and intrahepatic lipid metabolism. Whether MFN2 is associated with hepatic lipid metabolism in dairy cows with moderate fatty liver is unknown. Therefore, to investigate changes in MFN2 expression and lipid metabolic status in dairy cows with moderate fatty liver, blood and liver samples were collected from healthy dairy cows (n = 10) and cows with moderate fatty liver (n = 10). To determine the effects of MFN2 on lipid metabolism in vitro, hepatocytes isolated from healthy calves were used for small interfering RNA-mediated silencing of MFN2 or adenovirus-mediated overexpression of MFN2 for 48 h, or treated with 0, 0.6, 1.2, or 2.4 mM NEFA for 12 h. Milk production and plasma glucose concentrations in dairy cows with moderate fatty liver were lower, but concentrations of NEFA and ß-hydroxybutyrate (BHB) were greater in dairy cows with moderate fatty liver. Dairy cows with moderate fatty liver displayed hepatic lipid accumulation and lower abundance of hepatic MFN2, peroxisome proliferator-activated receptor-α (PPARα), and carnitine palmitoyltransferase 1A (CPT1A). However, sterol regulatory element-binding protein 1c (SREBP-1c), acetyl CoA carboxylase 1 (ACACA), fatty acid synthase (FASN), and diacylglycerol acyltransferase 1 (DGAT1) were more abundant in the livers of dairy cows with moderate fatty liver. In vitro, exogenous NEFA treatment upregulated abundance of SREBP-1c, ACACA, FASN, and DGAT1, and downregulated the abundance of PPARα and CPT1A. These changes were associated with greater lipid accumulation in calf hepatocytes, and MFN2 silencing aggravated this effect. In contrast, overexpression of MFN2-ameliorated exogenous NEFA-induced lipid accumulation by downregulating the abundance of SREBP-1c, ACACA, FASN, and DGAT1, and upregulating the abundance of PPARα and CPT1A in calf hepatocytes. Overall, these data suggest that one cause for the negative effect of excessive NEFA on hepatic lipid accumulation is the inhibition of MFN2. As such, these mechanisms partly explain the development of hepatic steatosis in dairy cows.


Assuntos
Doenças dos Bovinos/metabolismo , Bovinos/metabolismo , Fígado Gorduroso/veterinária , GTP Fosfo-Hidrolases/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Ácido 3-Hidroxibutírico/metabolismo , Animais , Bovinos/genética , Doenças dos Bovinos/enzimologia , Doenças dos Bovinos/genética , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Fígado Gorduroso/enzimologia , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Feminino , GTP Fosfo-Hidrolases/genética , Hepatócitos/enzimologia , Hepatócitos/metabolismo , Mitocôndrias/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
6.
Protein Eng Des Sel ; 32(1): 25-32, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31251342

RESUMO

Some bacteria belonging to the actinobacteria and proteobacteria groups can accumulate neutral lipids expressing enzymes of the wax ester synthase/acyl coenzyme A: diacylglycerol acyltransferase (WS/DGAT) family. tDGAT is a WS/DGAT-like enzyme from Thermomonospora curvata able to produce TAGs and WEs when heterologously expressed in Escherichia coli. In this study, a protocol for the directed evolution of bacterial lipid-producing enzymes based on fluorimetry is developed and tested. tDGAT has been successfully evolved towards the improvement of TAG production with an up to 2.5 times increase in TAG accumulation. Mutants with no ability to produce TAGs but able to accumulate waxes were also selected during the screening. The localization of the mutations that enhance TAG production in the outer surface of tDGAT points out possible new mechanisms that contribute to the activity of this family of enzymes. This Nile red-based high throughput screening provides an evolution platform for other WS/DGAT-like enzymes.


Assuntos
Actinobacteria/enzimologia , Proteínas de Bactérias/química , Diacilglicerol O-Aciltransferase/química , Evolução Molecular Direcionada , Actinobacteria/genética , Proteínas de Bactérias/genética , Diacilglicerol O-Aciltransferase/genética
7.
BMC Genomics ; 20(1): 402, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31117950

RESUMO

BACKGROUND: Cotton (Gossypium spp.) is the most important natural fiber crop worldwide, and cottonseed oil is its most important byproduct. Phospholipid: diacylglycerol acyltransferase (PDAT) is important in TAG biosynthesis, as it catalyzes the transfer of a fatty acyl moiety from the sn-2 position of a phospholipid to the sn-3 position of sn-1, 2-diacylglyerol to form triacylglycerol (TAG) and a lysophospholipid. However, little is known about the genes encoding PDATs involved in cottonseed oil biosynthesis. RESULTS: A comprehensive genome-wide analysis of G. hirsutum, G. barbadense, G. arboreum, and G. raimondii herein identified 12, 11, 6 and 6 PDATs, respectively. These genes were divided into 3 subfamilies, and a PDAT-like subfamily was identified in comparison with dicotyledonous Arabidopsis. All GhPDATs contained one or two LCAT domains at the C-terminus, while most GhPDATs contained a preserved single transmembrane region at the N-terminus. A chromosomal distribution analysis showed that the 12 GhPDAT genes in G. hirsutum were distributed in 10 chromosomes. However, none of the GhPDATs was co-localized with quantitative trait loci (QTL) for cottonseed oil content, suggesting that their sequence variations are not genetically associated with the natural variation in cottonseed oil content. Most GhPDATs were expressed during the cottonseed oil accumulation stage. Ectopic expression of GhPDAT1d increased Arabidopsis seed oil content. CONCLUSIONS: Our comprehensive genome-wide analysis of the cotton PDAT gene family provides a foundation for further studies into the use of PDAT genes to increase cottonseed oil content through biotechnology.


Assuntos
Diacilglicerol O-Aciltransferase/genética , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Família Multigênica , Fosfolipídeos/análise , Óleos Vegetais/análise , Proteínas de Plantas/genética , Diacilglicerol O-Aciltransferase/metabolismo , Evolução Molecular , Gossypium/crescimento & desenvolvimento , Gossypium/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Sementes/química
8.
J Agric Food Chem ; 67(21): 6007-6018, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31060359

RESUMO

4EBP1 is a chief downstream factor of mTORC1, and PPARγ is a key lipogenesis-related transcription factor. mTORC1 and PPARγ are associated with lipid metabolism. However, it is unknown which effector protein connects mTORC1 and PPARγ. This study investigated the interaction between 4EBP1 with PPARγ as part of the underlying mechanism by which insulin-induced lipid synthesis and secretion are regulated by mTORC1 in primary bovine mammary epithelial cells (pBMECs). Rapamycin, a specific inhibitor of mTORC1, downregulated 4EBP1 phosphorylation and the expression of PPARγ and the following lipogenic genes: lipin 1, DGAT1, ACC, and FAS. Rapamycin also decreased the levels of intracellular triacylglycerol (TAG); 10 types of fatty acid; and the accumulation of TAG, palmitic acid (PA), and stearic acid (SA) in the cell culture medium. Inactivation of mTORC1 by shRaptor or shRheb attenuated the synthesis and secretion of TAG and PA. In contrast, activation of mTORC1 by Rheb overexpression promoted 4EBP1 phosphorylation and PPARγ expression and upregulated the mRNA and protein levels of lipin 1, DGAT1, ACC, and FAS, whereas the levels of intracellular and extracellular TAG, PA, and SA also rose. Further, 4EBP1 interacted directly with PPARγ. Inactivation of mTORC1 by shRaptor prevented the nuclear location of PPARγ. These results demonstrate that mTORC1 regulates lipid synthesis and secretion by inducing the expression of lipin 1, DGAT1, ACC, and FAS, which is likely mediated by the 4EBP1/PPARγ axis. This finding constitutes a novel mechanism by which lipid synthesis and secretion are regulated in pBMECs.


Assuntos
Células Epiteliais/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Regulação da Expressão Gênica , Insulina/metabolismo , Lipogênese , Glândulas Mamárias Animais/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , PPAR gama/metabolismo , Animais , Carbono-Carbono Liases/genética , Carbono-Carbono Liases/metabolismo , Bovinos , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Fatores de Iniciação em Eucariotos/genética , Feminino , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/enzimologia , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , PPAR gama/genética , Triglicerídeos/metabolismo
9.
Biomed Pharmacother ; 115: 108950, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31078041

RESUMO

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide, mainly due to the absence of effective diagnostic biomarkers and therapeutic targets. Therefore, novel molecular targets are urgently needed, in order to formulate novel therapeutic approaches for this devastating disease. In the present study, we demonstrated that diacylglycerol acyltransferase 2 (Dgat2) was downregulated in human HCC tissues compared with in matched normal tissues. Furthermore, its high expression was significantly associated with longer survival. In addition, Dgat2 overexpression significantly suppressed HCC cell proliferation. in vivo studies, we revealed that the weight and volume of the tumors derived from Balb/c nude mice was markedly decreased when using HCC cells overexpressing Dgat2. Mechanism analysis demonstrated that cell cycle-related gene expressions were significantly downregulated in HCC cells overexpressing Dgat2. Taken together, these data suggest that Dgat2 is an important regulator of HCC cell proliferation, and could represent a potential anticancer target and diagnostic biomarker for HCC.


Assuntos
Carcinoma Hepatocelular/genética , Proliferação de Células/genética , Diacilglicerol O-Aciltransferase/genética , Regulação Neoplásica da Expressão Gênica , Genes cdc , Neoplasias Hepáticas/genética , Animais , Apoptose/genética , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Análise de Sobrevida , Regulação para Cima
10.
Gene ; 702: 75-82, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-30928362

RESUMO

Coconut (Cocos nucifera L.) is one of the most characteristic plants of tropical areas. Coconut oil and its derivatives have been widely used in various industries. In this paper, a type 2 diacylglycerol acyltransferase (DGAT2), which is one of the key enzymes involved in triacylglycerol (TAG) biosynthesis, was first characterized in coconut pulp (endosperm). The results indicated that CoDGAT2 was highly expressed in coconut pulp approximately 7 months after pollination. The heterologous expression of CoDGAT2 in the mutant yeast H1246 restored TAG biosynthesis in the yeast, which exhibited substrate preference for two unsaturated fatty acids (UFAs), palmitoleic acid (C16:1) and oleic acid (C18:1). Moreover, the seed-specific overexpression of CoDGAT2 in Arabidopsis thaliana led to a significant increase in the linoleic acid (C18:2) content (approximately 6%) compared with that in the wild type. In contrast, the proportions of eicosadienoic acid (C20:1) and arachidic acid (C20:0) were decreased. These results offer new insights on the function of CoDGAT2 in coconut and provide a novel molecular target for lipid genetic modification to change the fatty acid (FA) composition of oils.


Assuntos
Cocos/enzimologia , Diacilglicerol O-Aciltransferase/metabolismo , Endosperma/enzimologia , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Cocos/genética , Diacilglicerol O-Aciltransferase/genética , Endosperma/genética , Ácidos Graxos Insaturados/metabolismo , Genes de Plantas , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , RNA Mensageiro/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Sementes/metabolismo
11.
Appl Microbiol Biotechnol ; 103(9): 3727-3736, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30915502

RESUMO

Shea tree (Vitellaria paradoxa) is one economically important plant species that mainly distributes in West Africa. Shea butter extracted from shea fruit kernels can be used as valuable products in the food and cosmetic industries. The most valuable composition in shea butter was one kind of triacylglycerol (TAG), 1,3-distearoyl-2-oleoyl-glycerol (SOS, C18:0-C18:1-C18:0). However, shea butter production is limited and little is known about the genetic information of shea tree. In this study, we tried to reveal genetic information of shea tree and identified shea TAG biosynthetic genes for future shea butter production in yeast cell factories. First, we measured lipid content, lipid composition, and TAG composition of seven shea fruits at different ripe stages. Then, we performed transcriptome analysis on two shea fruits containing obviously different levels of SOS and revealed a list of TAG biosynthetic genes potentially involved in TAG biosynthesis. In total, 4 glycerol-3-phosphate acyltransferase (GPAT) genes, 8 lysophospholipid acyltransferase (LPAT) genes, and 11 diacylglycerol acyltransferase (DGAT) genes in TAG biosynthetic pathway were predicted from the assembled transcriptome and 14 of them were cloned from shea fruit cDNA. Furthermore, the heterologous expression of these 14 potential GPAT, LPAT, and DGAT genes in Saccharomyces cerevisiae changed yeast fatty acid and lipid profiles, suggesting that they functioned in S. cerevisiae. Moreover, two shea DGAT genes, VpDGAT1 and VpDGAT7, were identified as functional DGATs in shea tree, showing they might be useful for shea butter (SOS) production in yeast cell factories.


Assuntos
Proteínas de Plantas/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Sapotaceae/genética , Triglicerídeos/biossíntese , Leveduras/genética , Leveduras/metabolismo , Vias Biossintéticas , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Frutas/genética , Frutas/metabolismo , Engenharia Metabólica , Sapotaceae/enzimologia , Sapotaceae/metabolismo , Transcriptoma
12.
BMC Genomics ; 20(1): 128, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30744549

RESUMO

BACKGROUND: The availability of a unique unselected Holstein line since 1964 provided a direct comparison between selected and unselected Holstein genomes whereas large Holstein samples provided unprecedented statistical power for identifying high-confidence SNP effects. Utilizing these unique resources, we aimed to identify genome changes affected by selection since 1964. RESULTS: Direct comparison of genome-wide SNP markers between a Holstein line unselected since 1964 and contemporary Holsteins showed that the 40 years of artificial selection since 1964 resulted in genome landscape changes. Among the regions affected by selection, the regions containing 198 genes with fertility functions had a larger negative correlation than that of all SNPs between the SNP effects on milk yield and daughter pregnancy rate. These results supported the hypothesis that hitchhiking of genetic selection for milk production by negative effects of fertility genes contributed to the unintended declines in fertility since 1964. The genome regions subjected to selection also contained 67 immunity genes, the bovine MHC region of Chr23 with significantly decreased heterozygosity in contemporary Holsteins, and large gene clusters including T-cell receptor and immunoglobulin genes. CONCLUSIONS: This study for the first time provided direct evidence that genetic selection for milk production affected fertility and immunity genes and that the hitchhiking of genetic selection for milk production by negative fertility effects contributed to the fertility declines since 1964, and identified a large number of candidate fertility and immunity genes affected by selection. The results provided novel understanding about genome changes due to artificial selection and their impact on fertility and immunity genes and could facilitate developing genetic methods to reverse the declines in fertility and immunity in Holstein cattle.


Assuntos
Cruzamento , Bovinos/genética , Genômica , Animais , Bovinos/imunologia , Bovinos/metabolismo , Diacilglicerol O-Aciltransferase/genética , Fertilidade/genética , Frequência do Gene , Haplótipos , Humanos , Imunidade/genética , Leite/metabolismo , Polimorfismo de Nucleotídeo Único , Fatores de Tempo
13.
Proc Natl Acad Sci U S A ; 116(8): 3126-3135, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30718413

RESUMO

The balance of effector versus regulatory T cells (Tregs) controls inflammation in numerous settings, including multiple sclerosis (MS). Here we show that memory phenotype CD4+ T cells infiltrating the central nervous system during experimental autoimmune encephalomyelitis (EAE), a widely studied animal model of MS, expressed high levels of mRNA for Dgat1 encoding diacylglycerol-O-acyltransferase-1 (DGAT1), an enzyme that catalyzes triglyceride synthesis and retinyl ester formation. DGAT1 inhibition or deficiency attenuated EAE, with associated enhanced Treg frequency; and encephalitogenic, DGAT1-/- in vitro-polarized Th17 cells were poor inducers of EAE in adoptive recipients. DGAT1 acyltransferase activity sequesters retinol in ester form, preventing synthesis of retinoic acid, a cofactor for Treg generation. In cultures with T cell-depleted lymphoid tissues, retinol enhanced Treg induction from DGAT1-/- but not from WT T cells. The WT Treg induction defect was reversed by DGAT1 inhibition. These results demonstrate that DGAT1 suppresses retinol-dependent Treg formation and suggest its potential as a therapeutic target for autoimmune inflammation.


Assuntos
Diacilglicerol O-Aciltransferase/genética , Encefalomielite/genética , Inflamação/genética , Esclerose Múltipla/genética , Linfócitos T Reguladores/imunologia , Animais , Sistema Nervoso Central , Técnicas de Inativação de Genes , Humanos , Inflamação/imunologia , Inflamação/patologia , Camundongos , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Células Th1/imunologia , Células Th17/imunologia , Tretinoína/metabolismo
14.
Plant Foods Hum Nutr ; 74(1): 115-121, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30637573

RESUMO

Cinnamon polyphenol extract (CPE) improves people with insulin resistance. The objective was to investigate CPE and insulin on diacylglycerol acyltransferase (DGAT) gene expression important for lipid biosynthesis and compared it to anti-inflammatory tristetraprolin/zinc finger protein 36 (TTP/ZFP36) gene expression known to be regulated by both agents. Mouse 3T3-L1 adipocytes and RAW264.7 macrophages were treated with insulin and CPE followed by qPCR evaluation of DGAT and TTP mRNA levels. Insulin decreased DGAT1 and DGAT2 mRNA levels in adipocytes but had no effect on DGAT1 and increased DGAT2 mRNA levels 3-fold in macrophages. Insulin increased TTP mRNA levels 3-fold in adipocytes but had no effect in macrophages. CPE effect on DGAT1 gene expression was minimal but increased DGAT2 mRNA levels 2-4 fold in adipocytes and macrophages. CPE increased TTP mRNA levels 2-7 fold in adipocytes and macrophages. We conclude that CPE and insulin exhibited overlapping and independent effects on DGAT and TTP gene expression and suggest that CPE and insulin have profound effects on fat biosynthesis and inflammatory responses.


Assuntos
Cinnamomum zeylanicum/química , Diacilglicerol O-Aciltransferase/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/enzimologia , Animais , Diacilglicerol O-Aciltransferase/genética , Humanos , Resistência à Insulina , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Camundongos , Células RAW 264.7 , RNA Mensageiro/genética , Tristetraprolina/metabolismo
15.
Protein J ; 38(1): 83-94, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30697667

RESUMO

Amphibians are, currently, considered the first vertebrates that had performed the aquatic to terrestrial transition during evolution; therefore, water balance and dehydration control were prerequisites for such environment conquering. Among anurans, Phyllomedusa is a well-studied genus, due to its peptide-rich skin secretion. Here, we have analyzed the skin secretion of Phyllomedusa distincta targeting the proteins present in the skin secretion. The major soluble protein was chromatographically isolated and utilized to immunize rabbits. Through proteomics approaches, we were able to identify such protein as being the diacylglycerol O-acyltransferase 2 (DGAT2), a crucial enzyme involved in lipid synthesis and in the skin water balance. Immunohistochemistry assays revealed the protein tissular distribution for different animal species, belonging to different branches of the phylogenetic tree. Specifically, there was positivity to the anti-DGAT2 on Amphibians' skin, and no antibody recognition on fish and mammals' skins. The DGAT2 multiple sequence alignment reveals some degree of conservation throughout the genera; however, there is a different cysteine pattern among them. Molecular modeling analyses corroborate that the different cysteine pattern leads to distinct 3D structures, explaining the different antibody recognition. Moreover, the protein phylogenetic analyses place the Xenopus DGAT2 (the available amphibian representative) next to the Coelacanthus enzyme, which have led the authors to term this a 'paleo-protein'. DGAT2 would be, therefore, an ancient protein, crucial to the terrestrial environment conquest, with a unique folding-as indicated by the molecular models and immunohistochemistry analyses-a consequence of the different cysteine pattern but with conserved biological function.


Assuntos
Proteínas de Anfíbios/química , Diacilglicerol O-Aciltransferase/química , Evolução Molecular , Modelos Moleculares , Filogenia , Dobramento de Proteína , Proteínas de Anfíbios/genética , Animais , Anuros , Diacilglicerol O-Aciltransferase/genética
16.
Lipids Health Dis ; 18(1): 11, 2019 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-30621686

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is closely linked to obesity, type 2 diabetes and other metabolic disorders worldwide. Crocin is a carotenoid compound possessing various pharmacological activities. In the present study, we aimed to investigate the effect on fatty liver under diabetic and obese condition and to examine the possible role of AMP-activated protein kinase (AMPK) signaling. METHODS: db/db mice were administrated with crocin and injected with LV-shAMPK or its negative control lentivirus. Metabolic dysfunction, lipogenesis and fatty acid-oxidation in liver were evaluated. RESULTS: In db/db mice, we found that oral administration of crocin significantly upregulated the phosphorylation of AMPK and downregulated the phosphorylation of mTOR in liver. Crocin reduced liver weight, serum levels of alanine aminotransferase, alanine aminotransferase, and liver triglyceride content, and attenuated morphological injury of liver in db/db mice. Crocin inhibited the mRNA expression of lipogenesis-associated genes, including sterol regulatory element binding protein-1c, peroxisome proliferator-activated receptor γ, fatty acid synthase, stearoyl-CoA desaturase 1, and diacylglycerol acyltransferase 1, and increased the mRNA expression of genes involved in the regulation of ß-oxidation of fatty acids, including PPARα, acyl-CoA oxidase 1, carnitine palmitoyltransferase 1, and 3-hydroxy-3-methylglutaryl-CoA synthase 2. Moreover, treatment of crocin resulted in a amelioration of general metabolic disorder, as evidenced by decreased fasting blood glucose, reduced serum levels of insulin, triglyceride, total cholesterol, and non-esterified fatty acid, and improved glucose intolerance. Crocin-induced protective effects against fatty liver and metabolic disorder were significantly blocked by lentivirus-mediated downregulation of AMPK. CONCLUSIONS: The results suggest that crocin can inhibit lipogenesis and promote ß-oxidation of fatty acids through activation of AMPK, leading to improvement of fatty liver and metabolic dysfunction. Therefore, crocin may be a potential promising option for the clinical treatment for NAFLD and associated metabolic diseases.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Fármacos Antiobesidade/farmacologia , Carotenoides/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Proteínas Quinases Ativadas por AMP/metabolismo , Acil-CoA Oxidase/genética , Acil-CoA Oxidase/metabolismo , Alanina Transaminase/sangue , Alanina Transaminase/genética , Animais , Aspartato Aminotransferases/sangue , Aspartato Aminotransferases/genética , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Modelos Animais de Doenças , Ácido Graxo Sintases/antagonistas & inibidores , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Regulação da Expressão Gênica , Hidroximetilglutaril-CoA Sintase/genética , Hidroximetilglutaril-CoA Sintase/metabolismo , Lipogênese/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , PPAR alfa/agonistas , PPAR alfa/genética , PPAR alfa/metabolismo , PPAR gama/antagonistas & inibidores , PPAR gama/genética , PPAR gama/metabolismo , Transdução de Sinais , Estearoil-CoA Dessaturase/antagonistas & inibidores , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/antagonistas & inibidores , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Resultado do Tratamento , Triglicerídeos/sangue
17.
Mol Omics ; 15(1): 50-58, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30603757

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. Being part of the metabolic syndrome, NAFLD is characterized by the deposition of triglycerides (TGs) as lipid droplets in the cytoplasm of hepatic cells. Recently, the rapid development of high-throughput genome analysis technologies provided opportunities to screen for new drugs for NAFLD. In this study, we screened for potential drugs based on the gene expression profiles of 73 compounds and identified histone deacetylase (HDAC) inhibitors as a novel treatment for the accumulation of lipids in hepatocytes. In the subsequent analysis and experiments, we discovered that SAHA inhibited the fatty acid and lipid metabolism pathways in hepatic cells and induced a significant deficiency of lipid accumulation in HepG2 and SMMC-7721 cells. Furthermore, SAHA inhibited lipid synthesis in hepatic cells by directly suppressing the expression of DGAT2. Hence, our study provides a novel method to screen for effective drugs for liver diseases and identifies SAHA as a potent treatment for NAFLD.


Assuntos
Avaliação Pré-Clínica de Medicamentos , Perfilação da Expressão Gênica , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Vorinostat/uso terapêutico , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Histona Desacetilase 2/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Lipídeos/biossíntese , Ácido Oleico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Vorinostat/farmacologia
18.
Plant Biotechnol J ; 17(4): 776-788, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30230695

RESUMO

Thlapsi arvense L. (pennycress) is being developed as a profitable oilseed cover crop for the winter fallow period throughout the temperate regions of the world, controlling soil erosion and nutrients run-off on otherwise barren farmland. We demonstrate that pennycress can serve as a user-friendly model system akin to Arabidopsis that is well-suited for both laboratory and field experimentation. We sequenced the diploid genome of the spring-type Spring 32-10 inbred line (1C DNA content of 539 Mb; 2n = 14), identifying variation that may explain phenotypic differences with winter-type pennycress, as well as predominantly a one-to-one correspondence with Arabidopsis genes, which makes translational research straightforward. We developed an Agrobacterium-mediated floral dip transformation method (0.5% transformation efficiency) and introduced CRISPR-Cas9 constructs to produce indel mutations in the putative FATTY ACID ELONGATION1 (FAE1) gene, thereby abolishing erucic acid production and creating an edible seed oil comparable to that of canola. We also stably transformed pennycress with the Euonymus alatus diacylglycerol acetyltransferase (EaDAcT) gene, producing low-viscosity acetyl-triacylglycerol-containing seed oil suitable as a diesel-engine drop-in fuel. Adoption of pennycress as a model system will accelerate oilseed-crop translational research and facilitate pennycress' rapid domestication to meet the growing sustainable food and fuel demands.


Assuntos
Arabidopsis/genética , Diacilglicerol O-Aciltransferase/metabolismo , Euonymus/enzimologia , Genoma de Planta/genética , Óleos Vegetais/metabolismo , Thlaspi/genética , Produtos Agrícolas , Diacilglicerol O-Aciltransferase/genética , Ácidos Erúcicos/metabolismo , Euonymus/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/metabolismo , Thlaspi/metabolismo
19.
J Dairy Sci ; 102(1): 742-753, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30447981

RESUMO

An annual pattern of milk composition has been well recognized in dairy cattle, with the highest milk fat and protein concentration observed during the winter and lowest occurring in the summer; however, rhythms of milk yield and composition have not been well quantified. Cosinor rhythmometry is commonly used to model repeating daily and annual rhythms and allows determination of the amplitude (peak to mean), acrophase (time at peak), and period (time between peaks) of the rhythm. The objective of this study was to use cosinor rhythmometry to characterize the annual rhythms of milk yield and milk fat and protein concentration and yield using both national milk market and cow-level data. First, 10 yr of monthly average milk butterfat and protein concentration for each Federal Milk Marketing Order were obtained from the US Department of Agriculture Agricultural Marketing Service database. Fat and protein concentration fit a cosine function with a 12-mo period in all milk markets. We noted an interaction between milk marketing order and milk fat and protein concentration. The acrophase (time at peak) of the fat concentration rhythm ranged from December 4 to January 19 in all regions, whereas the rhythm of protein concentration peaked between December 27 and January 6. The amplitude (peak to mean) of the annual rhythm ranged from 0.07 to 0.14 percentage points for milk fat and from 0.08 to 0.12 percentage points for milk protein. The amplitude of the milk fat rhythm generally was lower in southern markets and higher in northern markets. Second, the annual rhythm of milk yield and milk fat and protein yield and concentration were analyzed in monthly test day data from 1,684 cows from 11 tiestall herds in Pennsylvania. Fat and protein concentration fit an annual rhythm in all herds, whereas milk and milk fat and protein yield only fit rhythms in 8 of the 11 herds. On average, milk yield peaked in April, fat and protein yield peaked in February, fat concentration peaked in January, and protein concentration peaked in December. Amplitudes of milk, fat, and protein yield averaged 0.82 kg, 55.3 g, and 30.4 g, respectively. Milk fat and protein concentration had average amplitudes of 0.12 and 0.07, respectively, similar to the results of the milk market data. Generally, milk yield and milk components fit annual rhythm regardless of parity or diacylglycerol O-acyltransferase 1 (DGAT1) K232A polymorphism, with only cows of the low-frequency AA genotype (5.2% of total cows) failing to fit rhythm of milk yield. In conclusion, the yearly rhythms of milk yield and fat and protein concentration and yield consistently occur regardless of region, herd, parity, or DGAT1 genotype and supports generation by a conserved endogenous annual rhythm.


Assuntos
Bovinos/fisiologia , Gorduras/análise , Lactação/fisiologia , Proteínas do Leite/análise , Leite/química , Estações do Ano , Animais , Bovinos/genética , Indústria de Laticínios , Diacilglicerol O-Aciltransferase/genética , Feminino , Genótipo , Lactação/genética , Proteínas do Leite/biossíntese , Paridade , Pennsylvania , Periodicidade , Polimorfismo Genético , Gravidez , Estados Unidos
20.
J Agric Food Chem ; 67(1): 291-298, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30543104

RESUMO

Diacylglycerol acyltransferase (DGAT) catalyzes the last and committed step of the acyl-CoA-dependent TAG biosynthesis and thus is a key target for manipulating oil production in microalgae. The microalga Chromochloris zofingiensis can accumulate substantial amounts of triacylglycerol (TAG) and represents a promising source of algal lipids. In this study, C. zofingiensis DGAT2s (CzDGAT2s) were characterized with in silico, in vivo (yeast), and in vitro assays. Putative CzDGAT2s were identified, and their functional motifs and evolutionary relationship with other DGAT2s were analyzed. When CzDGAT2s were individually expressed in a TAG-deficient Saccharomyces cerevisiae strain, only CzDGAT2C could restore the TAG biosynthesis. Further in vitro assays indicated that CzDGAT2C displayed typical DGAT activity, which was fitted to the Michaelis-Menten equation, and N- and C-terminals were important for the enzyme activity. In addition, membrane yeast two-hybrid assay revealed a possible DGAT2 activity modulation via the formation of homodimer/heterodimer among different DGAT2 isoforms.


Assuntos
Clorófitas/enzimologia , Diacilglicerol O-Aciltransferase/química , Microalgas/enzimologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Clorófitas/química , Clorófitas/classificação , Clorófitas/genética , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Dimerização , Cinética , Microalgas/química , Microalgas/classificação , Microalgas/genética , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Triglicerídeos/metabolismo
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