Biochimie最新文献

{"title":"Structural characterization of a galectin from the marine sponge Aplysina lactuca (ALL) with synergistic effects when associated with antibiotics against bacteria","authors":"Jéssica de Assis Duarte ,&nbsp;José Eduardo de Oliveira Neto ,&nbsp;Renato Cézar Farias Torres ,&nbsp;Andressa Rocha de Oliveira Sousa ,&nbsp;Alexandre Lopes Andrade ,&nbsp;Renata Pinheiro Chaves ,&nbsp;Rômulo Farias Carneiro ,&nbsp;Mayron Alves de Vasconcelos ,&nbsp;Claudener Souza Teixeira ,&nbsp;Edson Holanda Teixeira ,&nbsp;Celso Shiniti Nagano ,&nbsp;Alexandre Holanda Sampaio","doi":"10.1016/j.biochi.2023.07.003","DOIUrl":"10.1016/j.biochi.2023.07.003","url":null,"abstract":"<div><p><span><span>Lectins presents the ability to interact with glycans and trigger varied responses, including the inhibition of the development of various pathogens. Structural studies of these proteins are essential to better understand their functions. In marine sponges, so far only a few lectins have their </span>primary structures completely determined. Thus, the objective of this work was to structurally characterize and evaluate antibacterial potential, in association with different antibiotics, of the lectin isolated from the marine sponge </span><em>Aplysina lactuta</em><span> (ALL). ALL<span><span> is a homotetramer<span><span><span> of 60 kDa formed by four 15 kDa-subunits. The lectin showed affinity only for the glycoproteins </span>fetuin<span><span>, asialofetuin, mucin type III, and bovine submaxillary mucin type I. The complete amino acid sequences of two isoforms of ALL, named ALL-a and ALL-b, were determined by a combination of </span>Edman degradation and overlapped peptides sequenced by </span></span>tandem mass spectrometry<span>. ALL-a and ALL-b have 144 amino acids<span> with molecular masses of 15,736 Da and 15,985 Da, respectively. Both structures contain conserved residues typical of the galectin family. ALL is a protein with antibacterial potential, when in association with </span></span></span></span>ampicillin and oxacillin the lectin potentiates its antibiotic effect, included Methicillin-resistant </span></span><em>Staphylococcus</em> strains. Thus, ALL shows to be a molecule with potential for the development of new antibacterial drugs.</p></div>","PeriodicalId":251,"journal":{"name":"Biochimie","volume":"214 ","pages":"Pages 165-175"},"PeriodicalIF":3.9,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9871721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of MGP gene expression in cancer and contribution to prognosis","authors":"Helena Caiado ,&nbsp;M. Leonor Cancela ,&nbsp;Natércia Conceição","doi":"10.1016/j.biochi.2023.06.004","DOIUrl":"10.1016/j.biochi.2023.06.004","url":null,"abstract":"<div><p>Matrix Gla protein (MGP) was first identified as a calcification physiological inhibitor and the causal agent of the Keutel syndrome. <em>MGP</em> has been suggested to play a role in development, cell differentiation, and tumorigenesis. This study aimed to compare <em>MGP</em> expression and methylation status in different tumors and adjacent tissues, using The Cancer Genome Atlas (TCGA) data repository. We investigated if changes in <em>MGP</em> mRNA expression were correlated to cancer progression and whether the correlation coefficients could be used for prognosis. Strong correlations were observed between altered <em>MGP</em> levels and disease progression in breast, kidney, liver, and thyroid cancers, suggesting that it could be used to complement current clinical biomarker assays, for early cancer diagnosis.</p><p>We have also analyzed <em>MGP</em> methylation and identified CpG sites in its promoter and first intron with clear differences in methylation status between healthy and tumoral tissue providing evidence for epigenetic regulation of <em>MGP</em> transcription. Furthermore, we demonstrate that these alterations correlate with the overall survival of the patients suggesting that its assessment can serve as an independent prognostic indicator of patients’ survival.</p></div>","PeriodicalId":251,"journal":{"name":"Biochimie","volume":"214 ","pages":"Pages 49-60"},"PeriodicalIF":3.9,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0300908423001426/pdfft?md5=4e23cb314bd70bb4664d78bf342865e5&pid=1-s2.0-S0300908423001426-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9664544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A snapshot of Bothrops jararaca snake venom gland subcellular proteome","authors":"Maurício Frota Camacho ,&nbsp;Daniel R. Stuginski ,&nbsp;Débora Andrade-Silva ,&nbsp;Milton Y. Nishiyama-Jr ,&nbsp;Richard H. Valente ,&nbsp;André Zelanis","doi":"10.1016/j.biochi.2023.06.005","DOIUrl":"10.1016/j.biochi.2023.06.005","url":null,"abstract":"<div><p><span><span>Snake venom protein synthesis undergoes finely regulated processes in the specialized secretory epithelium within the venom gland. Such processes occur within a defined period in the cell and at specific cellular locations. Thus, the determination of subcellular </span>proteomes<span> allows the characterization of protein groups for which the site may be relevant to their biological roles, thereby allowing the deconvolution of complex biological circuits into functional information. In this regard, we performed subcellular fractionation of proteins from </span></span><em>B. jararaca</em><span> venom gland, focusing on nuclear proteins since this cellular compartment comprises key effectors that shape gene expression. Our results provided a snapshot of </span><em>B. jararaca's</em> subcellular venom gland proteome and pointed to a ‘conserved’ proteome core among different life stages (newborn and adult) and between sexes (adult male and female). Overall, the top 15 highly abundant proteins identified in <em>B. jararaca</em> venom glands mirrored the panel of highly expressed genes in human salivary glands. Therefore, the expression profile observed for such a protein set could be considered a conserved core signature of salivary gland secretory epithelium. Moreover, the newborn venom gland displayed a unique expression signature of transcription factors involved in regulating transcription and biosynthetic processes and may mirror biological constraints of the ontogenetic development of <em>B. jararaca</em>, contributing to venom proteome diversity.</p></div>","PeriodicalId":251,"journal":{"name":"Biochimie","volume":"214 ","pages":"Pages 1-10"},"PeriodicalIF":3.9,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9714766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Kinetics of the enzyme titration process by reversible modifiers","authors":"S.O. Karakhim","doi":"10.1016/j.biochi.2023.06.001","DOIUrl":"10.1016/j.biochi.2023.06.001","url":null,"abstract":"<div><p>The effect of reversible modifiers on the initial rate of enzyme catalysed reactions has been investigated in a quasi-equilibrium approximation using the general modifier mechanism of Botts and Morales. It has been shown that, when investigating the dependence of the initial rate on the modifier concentration at a fixed substrate concentration, the kinetics of enzyme titration by reversible modifiers can generally be described using two kinetic constants. Just as the dependence of the initial rate on the substrate concentration (at a fixed modifier concentration) is described using two kinetic constants: the Michaelis constant <em>K</em>_<em>m</em> and the limiting rate <em>V</em>_<em>m</em>. Only one constant <em>M</em>₅₀ is needed to describe the kinetics of linear inhibition, and in the case of nonlinear inhibition and activation, along with <em>M</em>₅₀ the constant <em>Q</em>_<em>M</em> is also needed.</p><p>Knowing the values of the constants <em>M</em>₅₀ and <em>Q</em>_<em>M</em>, it is possible to unambiguously determine the modification efficiency, that is, to calculate how many times the initial rate of the enzyme catalysed reaction will change when a certain modifier concentration is added to the incubation medium.</p><p>The properties of these fundamental constants have been analysed in detail and the dependence of these constants on other parameters of the Botts-Morales model have been shown. Equations describing the dependence of relative reaction rates on the modifier concentration using these kinetic constants are presented. Various ways of linearising these equations for calculating the kinetic constants <em>M</em>₅₀ and <em>Q</em>_<em>M</em> from experimental data are also presented.</p></div>","PeriodicalId":251,"journal":{"name":"Biochimie","volume":"214 ","pages":"Pages 11-26"},"PeriodicalIF":3.9,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0300908423001396/pdfft?md5=3d175237a013f5a655225c5f1f80d0ec&pid=1-s2.0-S0300908423001396-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9726164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Links between oral microbiome and insulin resistance: Involvement of MAP kinase signaling pathway","authors":"Yi-Ru Chang ,&nbsp;Wen-Chi Cheng ,&nbsp;Ya-Chun Hsiao ,&nbsp;Guan-Wei Su ,&nbsp;Shan-Jen Lin ,&nbsp;Yu-Shan Wei ,&nbsp;Hsiu-Chuan Chou ,&nbsp;Hsiu-Ping Lin ,&nbsp;Guan-Yu Lin ,&nbsp;Hong-Lin Chan","doi":"10.1016/j.biochi.2023.06.013","DOIUrl":"10.1016/j.biochi.2023.06.013","url":null,"abstract":"<div><p><span><span><span>Oral dysbiosis contributes to periodontitis and has implications for systemic diseases. Diabetes mellitus is a common metabolic disorder characterized by impaired glucose regulation. AMP-activated protein kinase (AMPK) plays a vital role in regulating </span>glucose uptake and </span>glycogenesis<span><span> in the liver. This study aimed to investigate the association between periodontal bacteria and diabetes mellitus. A clinical trial was conducted to explore the association between </span>oral bacteria<span> and hyperglycemia. Additionally, we elucidated the molecular mechanisms by which periodontal bacteria cause insulin resistance. In the clinical trial, we discovered significant alterations in the expression levels of </span></span></span><span><em>Fusobacterium nucleatum</em></span> (Fn) and <span><em>Tannerella forsythia</em></span><span><span> (Tf) in patients with diabetes compared with healthy controls. Furthermore, Fn and Tf levels positively correlated with fasting blood glucose and </span>glycated hemoglobin (HbA1C) levels. Moreover, we explored and elucidated the molecular mechanism by which </span><em>Fusobacterium nucleatum</em><span><span><span> culture filtrate (FNCF) induces cytokine release via the Toll-like receptor 2 (TLR2) </span>signaling pathway in human gingival epithelial Smulow–Glickman (S–G) cells. This study investigated the effects of cytokines on insulin resistance pathways in liver cells. The use of an extracellular signal-regulated kinase (ERK) inhibitor (U0126) demonstrated that FNCF regulates the </span>insulin receptor<span><span> substrate 1 and protein kinase B (IRS1/AKT) signaling pathway, which affects key proteins involved in hepatic glycogen synthesis, including </span>glycogen synthase kinase-3 beta (GSK3β) and glycogen synthase (GS), ultimately leading to insulin resistance. These findings suggest that ERK plays a crucial role in hepatocyte insulin resistance.</span></span></p></div>","PeriodicalId":251,"journal":{"name":"Biochimie","volume":"214 ","pages":"Pages 134-144"},"PeriodicalIF":3.9,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9891059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural study and antimicrobial and wound healing effects of lectin from Solieria filiformis (Kützing) P.W.Gabrielson","authors":"Renata Pinheiro Chaves ,&nbsp;Ana Kátia Barbosa dos Santos ,&nbsp;Alexandre Lopes Andrade ,&nbsp;Aryane de Azevedo Pinheiro ,&nbsp;Juliana Meneses de Sena Silva ,&nbsp;Francisca Manuela Santos da Silva ,&nbsp;Jucilene Pereira de Sousa ,&nbsp;Ito Liberato Barroso Neto ,&nbsp;Eduardo Henrique Salviano Bezerra ,&nbsp;Jade Oliveira Abreu ,&nbsp;Fátima Cristiane Teles de Carvalho ,&nbsp;Oscarina Viana de Sousa ,&nbsp;Bruno Lopes de Sousa ,&nbsp;Bruno Anderson Matias da Rocha ,&nbsp;André Luis Coelho Silva ,&nbsp;Luiz Gonzaga do Nascimento Neto ,&nbsp;Mayron Alves de Vasconcelos ,&nbsp;Edson Holanda Teixeira ,&nbsp;Rômulo Farias Carneiro ,&nbsp;Alexandre Holanda Sampaio ,&nbsp;Celso Shiniti Nagano","doi":"10.1016/j.biochi.2023.05.016","DOIUrl":"10.1016/j.biochi.2023.05.016","url":null,"abstract":"<div><p><span>The SfL-1 isoform<span> from the marine red algae </span></span><em>Solieria filiformis</em><span> was produced in recombinant form (rSfL-1) and showed hemagglutinating activity and inhibition similar to native SfL. The analysis of circular dichroism<span><span> revealed the predominance of β-strands structures with spectra of βI-proteins for both lectins, which had Melting Temperature (Tm) between 41 °C and 53 °C. The three-dimensional structure of the rSfL-1 was determined by X-ray crystallography, revealing that it is composed of two β-barrel domains formed by five antiparallel </span>β chains linked by a short peptide between the β-barrels. SfL and rSfL-1 were able to agglutinate strains of </span></span><em>Escherichia coli</em> and <span><em>Staphylococcus aureus</em></span><span> and did not show antibacterial activity. However, SfL induced a reduction in </span><em>E. coli</em> biomass at concentrations from 250 to 125 μg mL⁻¹, whereas rSfL-1 induced reduction in all concentrations tested. Additionally, rSfL-1 at concentrations from 250 to 62.5 μg mL⁻¹<span>, showed a statistically significant reduction in the number of colony-forming units, which was not noticed for SfL. Wound healing assay showed that the treatments with SfL and rSfL-1 act in reducing the inflammatory response and in the activation and proliferation of fibroblasts by a larger and fast deposition of collagen.</span></p></div>","PeriodicalId":251,"journal":{"name":"Biochimie","volume":"214 ","pages":"Pages 61-76"},"PeriodicalIF":3.9,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10032590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functional implications and therapeutic targeting of androgen response elements in prostate cancer","authors":"Dhirodatta Senapati ,&nbsp;Vikas Sharma ,&nbsp;Santosh Kumar Rath ,&nbsp;Uddipak Rai ,&nbsp;Naresh Panigrahi","doi":"10.1016/j.biochi.2023.07.012","DOIUrl":"10.1016/j.biochi.2023.07.012","url":null,"abstract":"<div><p><span><span>The androgen receptor (AR) plays an essential role in the growth and progression of prostate cancer (CaP). Ligand-activated AR inside the nucleus binds to the androgen response element (ARE) of the target genes in dimeric form and recruits transcriptional machinery to facilitate </span>gene transcription<span><span>. Pharmacological compounds that inhibit the AR action either bind to the ligand binding domain (LBD) or interfere with the interactions of AR with other co-regulatory proteins, slowing the progression of the disease. However, the emergence of resistance to conventional treatment makes clinical management of CaP difficult. Resistance has been associated with activation of androgen/AR axis that restores AR transcriptional activity. Activated AR signaling in resistance cases can be mediated by several mechanisms including AR amplification, gain-of-function AR mutations, androgen receptor variant (ARVs), intracrine </span>androgen production, and overexpression of AR coactivators. Importantly, in castration resistant prostate cancer, ARVs lacking the LBD become constitutively active and promote hormone-independent development, underlining the need to concentrate on the other domain or the AR-DNA interface for the identification of novel actionable targets. In this review, we highlight the plasticity of AR-DNA binding and explain how fine-tuning AR's cooperative </span></span>interactions with DNA translate into developing an alternative strategy to antagonize AR activity.</p></div>","PeriodicalId":251,"journal":{"name":"Biochimie","volume":"214 ","pages":"Pages 188-198"},"PeriodicalIF":3.9,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10239983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the arsenal of antimicrobial peptides: Mechanisms, diversity, and applications","authors":"Anna Savitskaya ,&nbsp;Jorge Masso-Silva ,&nbsp;Imen Haddaoui ,&nbsp;Shymaa Enany","doi":"10.1016/j.biochi.2023.07.016","DOIUrl":"10.1016/j.biochi.2023.07.016","url":null,"abstract":"<div><p><span>Antimicrobial peptides<span><span> (AMPs) are essential for defence against pathogens in all living organisms and possessed activities against bacteria, fungi, viruses, parasites and even cancer cells. AMPs are short peptides containing 12–100 amino acids<span> conferring a net positive charge and an amphiphilic property in most cases. Although, anionic AMPs also exist. AMPs can be classified based on the types of secondary structures, charge, </span></span>hydrophobicity, </span></span>amino acid composition, length, etc. Their mechanism of action usually includes a membrane disruption process through pore formation (three different models have been described, barrel-stave, toroidal or carpet model) but AMPs can also penetrate and impair intracellular functions. Besides their activity against pathogens, they have also shown immunomodulatory properties in complex scenarios through many different interactions. The aim of this review to summarize knowledge about AMP's and discuss the potential application of AMPs as therapeutics, the challenges due to their limitations, including their susceptibility to degradation, the potential generation of AMP resistance, cost, etc. We also discuss the current FDA-approved drugs based on AMPs and strategies to circumvent natural AMPs' limitations.</p></div>","PeriodicalId":251,"journal":{"name":"Biochimie","volume":"214 ","pages":"Pages 216-227"},"PeriodicalIF":3.9,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9915543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pathogenesis and therapeutic implications of matrix metalloproteinases in intervertebral disc degeneration: A comprehensive review","authors":"Xiaosong Zou ,&nbsp;Xingmin Zhang ,&nbsp;Song Han ,&nbsp;Lin Wei ,&nbsp;Zhi Zheng ,&nbsp;Yongjie Wang ,&nbsp;Jingguo Xin ,&nbsp;Shaokun Zhang","doi":"10.1016/j.biochi.2023.05.015","DOIUrl":"10.1016/j.biochi.2023.05.015","url":null,"abstract":"<div><p><span>Intervertebral disc (IVD) degeneration (IDD) is a common disorder that affects the spine and is a major cause of lower back pain (LBP). The extracellular matrix (ECM) is the structural foundation of the biomechanical properties of IVD, and its degradation is the main pathological characteristic of IDD. Matrix metalloproteinases (MMPs) are a group of </span>endopeptidases<span> that play an important role in the degradation and remodeling of the ECM. Several recent studies have shown that the expression and activity of many MMP subgroups are significantly upregulated in degenerated IVD tissue. This upregulation of MMPs results in an imbalance of ECM anabolism and catabolism, leading to the degradation of the ECM and the development of IDD. Therefore, the regulation of MMP expression is a potential therapeutic target for the treatment of IDD. Recent research has focused on identifying the mechanisms by which MMPs cause ECM degradation and promote IDD, as well as on developing therapies that target MMPs. In summary, MMP dysregulation is a crucial factor in the development of IDD, and a deeper understanding of the mechanisms involved is needed to develop effective biological therapies that target MMPs to treat IDD.</span></p></div>","PeriodicalId":251,"journal":{"name":"Biochimie","volume":"214 ","pages":"Pages 27-48"},"PeriodicalIF":3.9,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9726157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Responses and modulation of the white shrimp Litopenaeus vannamei glutathione peroxidases 2 and 4 during hypoxia, reoxygenation and GPx4 knock-down","authors":"Paulina Estrada-Cárdenas,&nbsp;Alma B. Peregrino-Uriarte,&nbsp;Silvia Gómez-Jiménez,&nbsp;Elisa M. Valenzuela-Soto,&nbsp;Lilia Leyva-Carrillo,&nbsp;Gloria Yepiz-Plascencia","doi":"10.1016/j.biochi.2023.07.006","DOIUrl":"10.1016/j.biochi.2023.07.006","url":null,"abstract":"<div><p><span><span><span>Glutathione peroxidases (GPxs) are important </span>antioxidant enzymes<span><span> that act at distinct levels of the antioxidant defense. In vertebrates, there are several glutathione peroxidase (GPx) </span>isoforms with different cellular and tissue distribution, but little is known about their interrelationships. The </span></span>shrimp </span><span><em>Litopenaeus vannamei</em></span><span> is the main crustacean cultivated worldwide. It is affected by environmental stressors, including hypoxia and reoxygenation that cause reactive oxygen species accumulation. Thus, the antioxidant response modulation is key for shrimp resilience. Recently, several GPx isoforms genes were identified in the </span><em>L. vannamei</em><span> genome sequence, but their functions are just beginning to be studied. As in vertebrates, shrimp GPx isoforms can present differences in their antioxidant responses. Also, there could be interrelationships among the isoforms that may influence their responses. We evaluated shrimp GPx2 and GPx4 expressions during hypoxia, reoxygenation, and GPx4 knock-down using RNAi for silencing, as well as the enzymatic activity of total GPx and GPx4. Also, glutathione content in hepatopancreas was evaluated. GPx2 and GPx4 presented similar expression patterns during hypoxia and reoxygenation. Their expressions decreased during hypoxia and were reestablished in reoxygenation at 6 h in non-silenced shrimp. GPx2 expression was down-regulated by GPx4 knock-down, suggesting that GPx4 affects GPx2 expression. Total GPx activity changed in hypoxia and reoxygenation at 6 h but not at 12 h, while GPx4 activity was not affected by any stressor. The GSH/GSSG ratio in hepatopancreas indicated that at early hours, the redox status remains well-modulated but at 12 h it is impaired by hypoxia and reoxygenation.</span></p></div>","PeriodicalId":251,"journal":{"name":"Biochimie","volume":"214 ","pages":"Pages 157-164"},"PeriodicalIF":3.9,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9847529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}