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1.
Dis Aquat Organ ; 156: 59-70, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38032039

RESUMO

Viral diseases are the most serious threat to the expansion and development of shrimp aquaculture. Rapid diagnosis of the white spot syndrome virus (WSSV), a lethal shrimp pathogen, is essential to restrict its spread and reduce the mortality of infected shrimp. This virus has globally affected the shrimp farming industry, with a devastating economic impact. Several studies have focused on the expression of WSSV transcripts to understand the molecular mechanisms governing the pathological development of the disease. Since gene expression studies and molecular diagnostics at the early stages of infection depend on the efficient isolation of high-quality RNA, the extraction methods should be carefully selected. However, previous comparisons of the performance of RNA isolation kits have yet to be systematically investigated. In this study, 5 commercial RNA extraction methods were compared in WSSV-infected shrimp. The highest total RNA yield (ng mg-1 tissue) was obtained using TRIzol. Even though the 260/280 nm absorption ratios showed significant differences, the methods showed good purity values (>2.0). RNA integrity was evaluated in a denaturing agarose gel electrophoresis, and degradation was observed after the total RNA samples were treated with DNase I. Finally, the method that allowed the earlier detection of WSSV transcripts by qRT-PCR was the Zymo Direct-zol RNA MiniPrep kit. This study shows that the amount of observed (or estimated) WSSV transcripts might be affected because of the RNA isolation method. In addition, these results may contribute to improve the accuracy of the results obtained in gene expression studies, for more sensitive and robust detection of WSSV.


Assuntos
Penaeidae , Vírus da Síndrome da Mancha Branca 1 , Animais , Vírus da Síndrome da Mancha Branca 1/genética , Reação em Cadeia da Polimerase/veterinária , Crustáceos , RNA , Aquicultura
2.
J Bioenerg Biomembr ; 51(2): 103-119, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30796582

RESUMO

Mitochondrial uncoupling proteins (UCP) transport protons from the intermembrane space to the mitochondrial matrix uncoupling oxidative phosphorylation. In mammals, these proteins have been implicated in several cellular functions ranging from thermoregulation to antioxidant defense. In contrast, their invertebrate homologs have been much less studied despite the great diversity of species. In this study, two transcripts encoding mitochondrial uncoupling proteins were, for the first time, characterized in crustaceans. The white shrimp Litopenaeus vannamei transcript LvUCP4 is expressed in all tested shrimp tissues/organs, and its cDNA includes a coding region of 954 bp long which encodes a deduced protein 318 residues long and a predicted molecular weight of 35.3 kDa. The coding region of LvUCP5 transcript is 906 bp long, encodes a protein of 302 residues with a calculated molecular weight of 33.17 kDa. Both proteins share homology with insect UCPs, their predicted structures show the conserved motifs of the mitochondrial carrier proteins and were confirmed to be located in the mitochondria through a Western blot analysis. The genic expression of LvUCP4 and LvUCP5 was evaluated in shrimp at oxidative stress conditions and results were compared to some antioxidant enzymes to infer about their antioxidant role. LvUCP4 and LvUCP5 genes expression did not change during hypoxia/re-oxygenation, and no coordinated responses were detected with antioxidant enzymes at the transcriptional level. Results confirmed UCPs as the first uncoupling mechanism reported in this species, but their role in the oxidative stress response remains to be confirmed.


Assuntos
Proteínas de Artrópodes/biossíntese , Regulação da Expressão Gênica/fisiologia , Mitocôndrias/metabolismo , Proteínas de Desacoplamento Mitocondrial/biossíntese , Penaeidae/metabolismo , Animais , Proteínas de Artrópodes/genética , Mitocôndrias/genética , Proteínas de Desacoplamento Mitocondrial/genética , Especificidade de Órgãos/fisiologia , Penaeidae/genética
3.
J Bioenerg Biomembr ; 50(2): 143-152, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29594796

RESUMO

Mitochondrial ATP is synthesized by coupling between the electron transport chain and complex V. In contrast, physiological uncoupling of these processes allows mitochondria to consume oxygen at high rates without ATP synthesis. Such uncoupling mechanisms prevent reactive oxygen species overproduction. One of these mechanisms are the alternative redox enzymes from the mitochondrial respiratory chain, which may help cells to maintain homeostasis under stress independently of ATP synthesis. To date, no reports have been published on alternative redox enzymes in crustaceans mitochondria. Specific inhibitors were used to identify alternative redox enzymes in mitochondria isolated from Artemia franciscana nauplii, and the white shrimp, Litopenaeus vannamei. We report the presence of two alternative redox enzymes in the respiratory chain of A. franciscana nauplii, whose isolated mitochondria used glycerol-3-phosphate as a substrate, suggesting the existence of a glycerol-3-phosphate dehydrogenase. In addition, cyanide and octyl-gallate were necessary to fully inhibit this species' mitochondrial oxygen consumption, suggesting an alternative oxidase is present. The in-gel activity analysis confirmed that additional mitochondrial redox proteins exist in A. franciscana. A mitochondrial glycerol-3-phosphate dehydrogenase oxidase was identified by protein sequencing as part of a branched respiratory chain, and an alternative oxidase was also identified in this species by western blot. These results indicate different adaptive mechanisms from artemia to face environmental challenges related to the changing levels of oxygen concentration in seawater through their life cycles. No alternative redox enzymes were found in shrimp mitochondria, further efforts will determine the existence of an uncoupling mechanism such as uncoupling proteins.


Assuntos
Artemia/química , Transporte de Elétrons , Mitocôndrias/metabolismo , Consumo de Oxigênio , Penaeidae/química , Adaptação Fisiológica , Animais , Glicerolfosfato Desidrogenase , Mitocôndrias/química , Proteínas Mitocondriais , Oxirredução , Oxirredutases , Proteínas de Plantas , Especificidade por Substrato
4.
J Bioenerg Biomembr ; 47(3): 223-34, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25731176

RESUMO

The mitochondrial FOF1 ATP synthase produces ATP in a reaction coupled to an electrochemical proton gradient generated by the electron transfer chain. The enzyme also hydrolyzes ATP according to the energy requirements of the organism. Shrimp need to overcome low oxygen concentrations in water and other energetic stressors, which in turn lead to mitochondrial responses. The aim of this study was to characterize the full-length cDNA sequences of three subunits that form the central stalk of the F1 catalytic domain of the ATP synthase of the white shrimp Litopenaeus vannamei and their deduced proteins. The effect of hypoxia on shrimp was also evaluated by measuring changes in the mRNA amounts of these subunits. The cDNA sequences of the nucleus-encoded ATPγ, ATPδ and ATPε subunits are 1382, 477 and 277 bp long, respectively. The three deduced amino acid sequences exhibited highly conserved regions when compared to homologous sequences, and specific substitutions found in shrimp subunits are discussed through an homology structural model of F1 ATP-synthase that included the five deduced proteins, which confirm their functional structures and specific characteristics from the cognate complex of ATP synthases. Genes expression was evaluated during hypoxia-reoxygenation, and resulted in a generalized down-regulation of the F1 subunits and no coordinated changes were detected among these five subunits. The reduced mRNA levels suggest a mitochondrial response to an oxidative stress event, similar to that observed at ischemia-reperfusion in mammals. This model analysis and responses to hypoxia-reoxygenation may help to better understand additional mitochondrial adaptive mechanisms.


Assuntos
Trifosfato de Adenosina/biossíntese , Hipóxia Celular/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , ATPases Mitocondriais Próton-Translocadoras/genética , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Modelos Moleculares , Penaeidae/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/genética , Perfilação da Expressão Gênica , ATPases Mitocondriais Próton-Translocadoras/química , Dados de Sequência Molecular , Conformação Proteica , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA
5.
J Bioenerg Biomembr ; 47(5): 383-93, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26302886

RESUMO

The whiteleg shrimp species Litopenaeus vannamei is exposed to cyclic changes of the dissolved oxygen concentration of seawater and must neutralize the adverse effects of hypoxia by using ATP as energy source. In crustaceans, the mitochondrial FOF1-ATP synthase is pivotal to the homeostasis of ATP and function prevalently as a FOF1-ATPase. Hitherto, it is unknown whether these marine invertebrates are equipped with molecules able to control the FOF1-ATPase inhibiting the ATP consumption. In this study, we report two variants of the mitochondrial FOF1-ATPase Inhibitory Factor 1 (IF1) ubiquitously expressed across tissues of the Litopenaeus vannamei transcriptome: the IF1_Lv1 and the IF1_Lv2. The IF1_Lv1, with a full-length sequence of 550 bp, encodes a 104 aa long protein and its mRNA amounts are significantly affected by hypoxia and re-oxygenation. The IF1_Lv2, with a sequence of 654 bp, encodes instead for a protein of 85 aa. Both proteins share a 69 % homology and contain a conserved minimal inhibitory sequence (IATP domain) along with a G-rich region on their N-terminus typical of the invertebrate. In light of this characterization IF1 is here discussed as an adaptive mechanism evolved by this marine species to inhibit the FOF1-ATPase activity and avoid ATP dissipation to thrive in spite of the changes in oxygen tension.


Assuntos
Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Penaeidae/genética , Penaeidae/metabolismo , Proteínas/genética , Proteínas/metabolismo , Animais , Sequência de Bases , Dados de Sequência Molecular , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo , Proteína Inibidora de ATPase
6.
J Exp Zool A Ecol Integr Physiol ; 339(3): 239-252, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36470843

RESUMO

The jellyfish genera Stomolophus spp. is one of the most abundant in the Pacific Ocean, yet it has not been thoroughly studied. Until recently, research has been developed and directed to its knowledge because of the economic interest in its exploitation. The genus Stomolophus in the Pacific Ocean is composed of five species (S. agaricus, S. chunii, S. collaris, S. fritillaria, and S. meleagris), and Stomolophus sp. 2 has been recently reported in the central part of the Gulf of California. Therefore, this study aimed to describe in vivo the different developmental stages of Stomolophus sp. 2 life cycle. As a result, multiple polyp reproduction forms were described, such as polyp-stolon formation, polydisc strobilation with more than 20 ephyrae formed by each strobila, and polyp formation directly from juvenile ephyra. In the degenerating phase, the polyps turned into cysts induced by stress conditions, such as changes in temperature, oxygen, and food availability. The life cycle of Stomolophus sp. 2 can be distinguished from that of S. meleagris by showing various asexual reproduction mechanisms and polydisc-like strobilation. The formation of polyps directly from the ectoderm of degenerating juvenile medusae suggests the possibility of a reversion cycle. Because of the different life cycles between S. meleagris and S. sp. 2, in addition to their morphological and genetic differences, this study proposes that Stomolophus sp. 2 should be considered a new species and suggests the name Stomolophus yaquilli, in reference to the indigenous community that lives in the species distribution area.


Assuntos
Estágios do Ciclo de Vida , Cifozoários , Animais , Cifozoários/genética , Temperatura , Alimentos , Reprodução
7.
Fish Shellfish Immunol ; 32(6): 1141-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22465360

RESUMO

The thioredoxin (TRX) system in crustaceans has demonstrated to act as a cell antioxidant being part of the immune response by dealing with the increased production of reactive oxygen species during bacterial or viral infection. Since the number of marine viruses has increased in the last years significantly affecting aquaculture practices of penaeids, and due to the adverse impact on wild and cultured shrimp populations, it is important to elucidate the dynamics of the shrimp response to viral infections. The role of Litopenaeus vannamei thioredoxin (LvTRX) was compared at both, mRNA and protein levels, in response to two viruses, the white spot syndrome virus (WSSV) and the infectious hypodermal and hematopoietic necrosis virus (IHHNV). The results confirmed changes in the TRX gene expression levels of WSSV-infected shrimp, but also demonstrated a more conspicuous response of TRX to WSSV than to IHHNV. While both the dimeric and monomeric forms of LvTRX were detected by Western blot analysis during the WSSV infection, the dimer on its reduced form was only detected through the IHHNV infectious process. These findings indicate that WSSV or IHHNV infected shrimp may induce a differential response of the LvTRX protein.


Assuntos
Densovirinae/fisiologia , Regulação da Expressão Gênica , Penaeidae , Tiorredoxinas/genética , Tiorredoxinas/imunologia , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Perfilação da Expressão Gênica , Brânquias/imunologia , Brânquias/virologia , Penaeidae/imunologia , Penaeidae/virologia , Fatores de Tempo
8.
Fish Shellfish Immunol ; 32(1): 230-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22080112

RESUMO

The invertebrate lysozyme (i-lyz or destabilase) is present in shrimp. This protein may have a function as a peptidoglycan-breaking enzyme and as a peptidase. Shrimp is commonly infected with Vibrio sp., a Gram-negative bacteria, and it is known that the c-lyz (similar to chicken lysozyme) is active against these bacteria. To further understand the regulation of lysozymes, we determined the gene sequence and modeled the protein structure of i-lyz. In addition, the expression of i-lyz and c-lyz in response to lipopolysaccharide (LPS) was studied. The shrimp i-lyz gene is interrupted by two introns with canonical splice junctions. The expression of the shrimp i-lyz was transiently down-regulated after LPS injection followed by induction after 6 h in hepatopancreas. In contrast, c-lyz was up-regulated in hepatopancreas 4 h post-injection and slightly down-regulated in gills. The L. vannamei i-lyz does not contain the catalytic residues for muramidase (glycohydrolase) neither isopeptidase activities; however, it is known that the antibacterial activity does not solely rely on the enzymatic activity of the protein. The study of invertebrate lysozyme will increase our understanding of the regulatory process of the defense mechanisms.


Assuntos
Adjuvantes Imunológicos/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Modelos Moleculares , Muramidase/química , Muramidase/genética , Penaeidae/enzimologia , Penaeidae/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Perfilação da Expressão Gênica , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Alinhamento de Sequência
9.
Mar Biotechnol (NY) ; 24(3): 480-491, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35384610

RESUMO

Scientific studies about decapod crustaceans' digestive physiology have increased, being an important topic with novel results in the last years. This revision aims to show how the study of crustacean peptidases has evolved, from the classical biochemical characterization studies to the assessment of their usefulness in biotechnological and industrial processes, with emphasis on commercial species of interest to world aquaculture and fisheries. First studies determined the proteolytic activity of the midgut gland crude extracts and evaluated the optimum biochemical properties of specific enzymes. Peptidase's identity was determined using inhibitors and specific protein substrates on tube tests and electrophoresis gels. Later, various studies focused on the characterization of purified peptidases and their gene expression. Recently, the integrated mechanisms of enzyme participation during the digestive process of food protein have been established using novel techniques. Scientific research has revealed some of the potential biotechnological applications of crustacean peptidases in the food industry and other processes. However, the knowledge field is enormous, and there is much to explore and study in the coming years.


Assuntos
Biotecnologia , Peptídeo Hidrolases , Aquicultura , Pesqueiros , Peptídeo Hidrolases/metabolismo , Proteólise
10.
J Anim Sci Technol ; 64(1): 52-69, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35174342

RESUMO

Ferulic acid (FA) is a phytochemical with various bioactive properties. It has recently been proposed that due to its phytogenic action it can be used as an alternative growth promoter additive to synthetic compounds. The objective of the present study was to evaluate the growth performance, carcass traits, fiber characterization and skeletal muscle gene expression on hair-lambs supplemented with two doses of FA. Thirty-two male lambs (n = 8 per treatment) were individually housed during a 32 d feeding trial to evaluate the effect of FA (300 and 600 mg d-1) or zilpaterol hydrochloride (ZH; 6 mg d-1) on growth performance, and then slaughtered to evaluate the effects on carcass traits, and muscle fibers morphometry from Longissimus thoracis (LT) and mRNA abundance of ß2-adrenergic receptor (ß2-AR), MHC-I, MHC-IIX and IGF-I genes. FA increased final weight and average daily gain with respect to non-supplemented animals (p < 0.05). The ZH supplementation increased LT muscle area, with respect to FA doses and control (p < 0.05). Cross-sectional area (CSA) of oxidative fibers was larger with FA doses and ZH (p < 0.05). Feeding ZH increased mRNA abundance for ß2-AR compared to FA and control (p < 0.05), and expression of MHC-I was affected by FA doses and ZH (p < 0.05). Overall, FA supplementation of male hair lambs enhanced productive variables due to skeletal muscle hypertrophy caused by MHC-I up-regulation. Results suggest that FA has the potential like a growth promoter in lambs.

11.
J Bioenerg Biomembr ; 43(2): 119-33, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21384180

RESUMO

In the mitochondrial F(O)F(1) ATP-synthase/ATPase complex, subunits α and ß are part of the extrinsic portion that catalyses ATP synthesis. Since there are no reports about genes and proteins from these subunits in crustaceans, we analyzed the cDNA sequences of both subunits in the whiteleg shrimp Litopenaeus vannamei and their phylogenetic relationships. We also investigated the effect of hypoxia on shrimp by measuring changes in the mRNA amounts of atpα and atpß. Our results confirmed highly conserved regions for both subunits and underlined unique features among others. The ATPß deduced protein of shrimp was less conserved in size and sequence than ATPα. The relative mRNA amounts of atpα and atpß changed in shrimp pleopods; hypoxia at 1.5 mg/L caused an increase in atpß transcripts and a subsequent decrease when shrimp were re-oxygenated. Results confirm that changes in the mRNAs of the ATP-synthase subunits are part of the mechanisms allowing shrimp to deal with the metabolic adjustment displayed to tolerate hypoxia.


Assuntos
Trifosfato de Adenosina/metabolismo , Domínio Catalítico/fisiologia , Hipóxia/enzimologia , Penaeidae/enzimologia , ATPases Translocadoras de Prótons/biossíntese , Trifosfato de Adenosina/genética , Animais , DNA Complementar/genética , DNA Complementar/metabolismo , Hipóxia/genética , Penaeidae/genética , ATPases Translocadoras de Prótons/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Análise de Sequência de Proteína
12.
Molecules ; 16(1): 532-42, 2011 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21228759

RESUMO

White spot syndrome virus (WSSV) is the causative agent of white spot syndrome, one of the most devastating diseases in shrimp aquaculture. The genome of WSSV includes a gene that encodes a putative family B DNA polymerase (ORF514), which is 16% identical in amino acid sequence to the Herpes virus 1 DNA polymerase. The aim of this work was to demonstrate the activity of the WSSV ORF514-encoded protein as a DNA polymerase and hence a putative antiviral target. A 3.5 kbp fragment encoding the conserved polymerase and exonuclease domains of ORF514 was overexpressed in bacteria. The recombinant protein showed polymerase activity but with very low level of processivity. Molecular modeling of the catalytic protein core encoded in ORF514 revealed a canonical polymerase fold. Amino acid sequence alignments of ORF514 indicate the presence of a putative PIP box, suggesting that the encoded putative DNA polymerase may use a host processivity factor for optimal activity. We postulate that WSSV ORF514 encodes a bona fide DNA polymerase that requires accessory proteins for activity and maybe target for drugs or compounds that inhibit viral DNA replication.


Assuntos
DNA Polimerase Dirigida por DNA/genética , Vírus da Síndrome da Mancha Branca 1/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Primers do DNA , DNA Polimerase Dirigida por DNA/química , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Fases de Leitura Aberta
13.
Animals (Basel) ; 11(8)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34438911

RESUMO

FA dietary supplementation on the growth performance, carcass traits and histochemical characteristics of the Longissimus thoracis muscle from finishing pigs was investigated. Four hundred and twenty pigs were used in this study, and 105 animals (with five replicate pens and 21 pigs per pen) were assigned to one of four treatments: basal diet (BD) without additives (C-); BD + 10 ppm ractopamine hydrochloride + 0.97% lysine (C+); BD + 25 ppm of FA (FA); and BD + 25 ppm of FA + 0.97% lysine (FA-Lys). Dietary supplementation with FA or ractopamine increased both the average daily gain (14%) and loin muscle area (19%), while fat deposition decreased by 53%, in comparison with C- (p < 0.05). The growth performance of pigs treated with FA was similar to those of ractopamine (p > 0.05). The histochemical analysis showed that FA and C+ treatments induced a shift in muscle fiber types: from fast fibers to intermediate (alkaline ATPase) and from oxidative to glycolytic fibers. Muscle tissues from animals treated with FA or ractopamine had a lower cross-sectional area and a greater number of muscle fibers per area (p < 0.05). Findings regarding growth performance and carcass traits indicate that FA supplementation at 25 ppm without extra-lysine can replace the use of ractopamine as a growth promoter in finishing pigs.

14.
J Comp Physiol B ; 191(4): 629-644, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33895873

RESUMO

In most eukaryotic organisms, mitochondrial uncoupling mechanisms control ATP synthesis and reactive oxygen species production. One such mechanism is the permeability transition of the mitochondrial inner membrane. In mammals, ischemia-reperfusion events or viral diseases may induce ionic disturbances, such as calcium overload; this cation enters the mitochondria, thereby triggering the permeability transition. This phenomenon increases inner membrane permeability, affects transmembrane potential, promotes mitochondrial swelling, and induces apoptosis. Previous studies have found that the mitochondria of some crustaceans do not exhibit a calcium-regulated permeability transition. However, in the whiteleg shrimp Litopenaeus vannamei, contradictory evidence has prevented this phenomenon from being confirmed or rejected. Both the ability of L. vannamei mitochondria to take up large quantities of calcium through a putative mitochondrial calcium uniporter with conserved characteristics and permeability transition were investigated in this study by determining mitochondrial responses to cations overload. By measuring mitochondrial swelling and transmembrane potential, we investigated whether shrimp exposure to hypoxia-reoxygenation events or viral diseases may induce mitochondrial permeability transition. The results of this study demonstrate that shrimp mitochondria take up large quantities of calcium through a canonical mitochondrial calcium uniporter. Neither calcium nor other ions were observed to promote permeability transition. This phenomenon does not depend on the life cycle stage of shrimp, and it is not induced during hypoxia/reoxygenation events or in the presence of viral diseases. The absence of the permeability transition phenomenon and its adaptive meaning are discussed as a loss with biological advantages, possibly enabling organisms to survive under harsh environmental conditions.


Assuntos
Mitocôndrias , Penaeidae , Animais , Cálcio/metabolismo , Hipóxia/metabolismo , Membranas Mitocondriais , Permeabilidade
15.
Meat Sci ; 177: 108490, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33744607

RESUMO

Muscle fiber morphometry and physicochemical characteristics were evaluated in LT muscles obtained from entire male lambs treated with zilpaterol hydrochloride (ZH, 0 and 0.15 mg/kg body weight) and/or steroidal implant (SI, with and without trenbolone acetate/estradiol). ZH and SI acted synergistically to increase LT area, type-IIb fiber cross-sectional area and soluble collagen content, likewise to decrease metmyoglobin concentration and insoluble collagen content. Ash content and ultimate pH showed a decrease due to an antagonistic effect between ZH and SI. Content of total collagen, protein, fat, moisture, oxidized lipids and water-holding capacity were unaffected by ZH and SI. Supplemental ZH, but not SI, decreased all color parameters and tended to increase shear force. Overall, the SI implantation of male lambs followed by a ZH supplementation promoted greater LT hypertrophy, without affecting protein and fat content, and physicochemical characteristics in their meat.


Assuntos
Fibras Musculares Esqueléticas/efeitos dos fármacos , Carne Vermelha/análise , Compostos de Trimetilsilil/farmacologia , Adrenérgicos/farmacologia , Animais , Cor , Estradiol/farmacologia , Masculino , Músculos Paraespinais/anatomia & histologia , Músculos Paraespinais/química , Resistência ao Cisalhamento , Carneiro Doméstico , Acetato de Trembolona/farmacologia
16.
Probiotics Antimicrob Proteins ; 13(4): 1033-1043, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33512646

RESUMO

Studies have shown that the intracellular content of probiotic (postbiotics) has antioxidant properties, which can improve the antioxidant status in vivo. However, its absorption and mechanisms underlying the protective effects are still unknown. The antioxidant capacity of Lacticaseibacillus casei CRL431 (IC-431) postbiotics was determined after an in vitro simulated digestive process. Permeability of antioxidant constituents of IC-431 was determined by an ex vivo everted duodenum assay. Aflatoxin B1-induced oxidative stress rat models were established and treated with IC-431; biomarkers of hepatic mitochondrial function and H2O2 levels, oxidative stress, and oxidative stress index (OSi) were examined. The antioxidant capacity of IC-431 (477 ± 45.25 µmol Trolox Equivalent/L) was reduced by exposure to the simulated digestive process. No difference (p > 0.05) was found among digested and the permeate fraction of IC-431. A protective effect was observed by significantly lower OSi and higher liver glutathione peroxidase and catalase activities. Lower H2O2 production, a higher degree of mitochondrial uncoupling, and lower mitochondrial respiration coefficient were also observed (p < 0.05). These results suggest that IC-431 antioxidant components permeate intestinal barriers to enter the bloodstream and regulate antioxidant status during AFB1-induced oxidative stress by reducing hepatic mitochondrial dysfunction, thus enhancing antioxidant enzyme response.


Assuntos
Aflatoxina B1 , Lacticaseibacillus casei , Mitocôndrias , Estresse Oxidativo , Probióticos , Aflatoxina B1/toxicidade , Animais , Antioxidantes , Peróxido de Hidrogênio , Mitocôndrias/fisiologia , Ratos
17.
Biochim Biophys Acta Bioenerg ; 1861(8): 148209, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32305415

RESUMO

Mitochondrial uncoupling proteins (UCPs) play an essential role in dissipating the proton gradient and controlling the mitochondrial inner membrane potential. When active, UCPs promote proton leak across the inner membrane, oxidative phosphorylation uncoupling, oxygen uptake increase and decrease the ATP synthesis. Invertebrates possess only isoforms UCP4 and UCP5, however, the role of these proteins is not clear in most species since it may depend on the physiological needs of each animal. This study presents the first functional characterization of crustacean uncoupling proteins from the white shrimp Litopenaeus vannamei LvUCP4 and LvUCP5. Free radicals production in various shrimp organs/tissues was first evaluated, and mitochondria were isolated from shrimp pleopods. The oxygen consumption rate, membrane potential and proton transport of the isolated non-phosphorylating mitochondria were used to determine LvUCPs activation/inhibition. Results indicate that UCPs activity is stimulated in the presence of 4-hydroxyl-2-nonenal (HNE) and myristic acid, and inhibited by the purine nucleotide GDP. A hypoxia/re-oxygenation assay was conducted to determine whether UCPs participate in shrimp mitochondria response to oxidative stress. Isolated mitochondria from shrimp at re-oxygenation produced large quantities of hydrogen peroxide and higher levels of both LvUCPs were immunodetected. Results suggest that, besides the active response of the shrimp antioxidant system, UCP-like activity is activated after hypoxia exposure and during re-oxygenation. LvUCPs may represent a mild uncoupling mechanism, which may be activated before the antioxidant system of cells, to early control reactive oxygen species production and oxidative damage in shrimp.


Assuntos
Proteínas de Desacoplamento Mitocondrial/metabolismo , Penaeidae , Animais , Peróxido de Hidrogênio/metabolismo , Potencial da Membrana Mitocondrial , Mitocôndrias/metabolismo , Oxigênio/metabolismo , Prótons , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
18.
AMB Express ; 10(1): 31, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32048056

RESUMO

Staphylococcus epidermidis is a Gram-positive saprophytic bacterium found in the microaerobic/anaerobic layers of the skin that becomes a health hazard when it is carried across the skin through punctures or wounds. Pathogenicity is enhanced by the ability of S. epidermidis to associate into biofilms, where it avoids attacks by the host and antibiotics. To test the effect of oxygen on metabolism and biofilm generation, cells were cultured at different oxygen concentrations ([O2]). As [O2] decreased, S. epidermidis metabolism went from respiratory to fermentative. Remarkably, the rate of growth decreased at low [O2] while a high concentration of ATP ([ATP]) was kept. Under hypoxic conditions bacteria associated into biofilms. Aerobic activity sensitized the cell to hydrogen peroxide-mediated damage. In the presence of metabolic inhibitors, biofilm formation decreased. It is suggested that at low [O2] S. epidermidis limits its growth and develops the ability to form biofilms.

19.
Meat Sci ; 158: 107890, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31382221

RESUMO

Forty hairbreed male lambs were used to evaluate the effects of zilpaterol hydrochloride (ZH, 0 and 0.15 mg/kg BW) and steroid implant (SI, without and with 52.5 mg trenbolone acetate and 7.5 mg 17ß-estradiol) on feedlot performance, carcass characteristics, non-carcass components, wholesale cut yield, and meat quality. Supplemental ZH increased growth rate, feed efficiency, carcass weight, and dressing percentage, with no effect on wholesale cut yields. Feeding ZH increased muscle pH at 24 h. Supplemental ZH increased meat shear force, but decreased lightness, redness, and yellowness after frozen storage followed by a 14-day aging period. The SI administration increased dressing percentage and neck yield, but decreased testicle weight and meat redness, without affecting other variables. The LT area was greater with ZH + SI administration than with individual application of ZH or SI. Compared to individual administration, simultaneous application of ZH and SI did not result in improved growth performance, carcass traits and wholesale cut yields in hairbreed male lambs.


Assuntos
Estrogênios/farmacologia , Carne Vermelha/normas , Carneiro Doméstico/crescimento & desenvolvimento , Compostos de Trimetilsilil/farmacologia , Adrenérgicos/farmacologia , Anabolizantes/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Composição Corporal/fisiologia , Dieta/veterinária , Estradiol/farmacologia , Armazenamento de Alimentos , Congelamento , Masculino , Músculo Esquelético/química , Acetato de Trembolona/farmacologia
20.
Mar Genomics ; 37: 74-81, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28923556

RESUMO

Palaemonetes argentinus, an abundant freshwater prawn species in the northern and central region of Argentina, has been used as a bioindicator of environmental pollutants as it displays a very high sensitivity to pollutants exposure. Despite their extraordinary ecological relevance, a lack of genomic information has hindered a more thorough understanding of the molecular mechanisms potentially involved in detoxification processes of this species. Thus, transcriptomic profiling studies represent a promising approach to overcome the limitations imposed by the lack of extensive genomic resources for P. argentinus, and may improve the understanding of its physiological and molecular response triggered by pollutants. This work represents the first comprehensive transcriptome-based characterization of the non-model species P. argentinus to generate functional genomic annotations and provides valuable resources for future genetic studies. Trinity de novo assembly consisted of 24,738 transcripts with high representation of detoxification (phase I and II), anti-oxidation, osmoregulation pathways and DNA replication and bioenergetics. This crustacean transcriptome provides valuable molecular information about detoxification and biochemical processes that could be applied as biomarkers in further ecotoxicology studies.


Assuntos
Desintoxicação Metabólica Fase II/genética , Desintoxicação Metabólica Fase I/genética , Palaemonidae/genética , Palaemonidae/metabolismo , Transcriptoma , Animais , Argentina , Biomarcadores/análise
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