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1.
J Virol ; 98(5): e0019824, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38591879

RESUMEN

The involvement of secreted phospholipase A2s in respiratory diseases, such as asthma and respiratory viral infections, is well-established. However, the specific role of secreted phospholipase A2 group IIE (PLA2G2E) during influenza virus infection remains unexplored. Here, we investigated the role of PLA2G2E during H1N1 influenza virus infection using a targeted mouse model lacking Pla2g2e gene (Pla2g2e-/-). Our findings demonstrated that Pla2g2e-/- mice had significantly lower survival rates and higher viral loads in lungs compared to wild-type mice following influenza virus infection. While Pla2g2e-/- mice displayed comparable innate and humoral immune responses to influenza virus challenge, the animals showed impaired influenza-specific cellular immunity and reduced T cell-mediated cytotoxicity. This indicates that PLA2G2E is involved in regulating specific T cell responses during influenza virus infection. Furthermore, transgenic mice expressing the human PLA2G2E gene exhibited resistance to influenza virus infection along with enhanced influenza-specific cellular immunity and T cell-mediated cytotoxicity. Pla2g2e deficiency resulted in perturbation of lipid mediators in the lung and T cells, potentially contributing to its impact on the anti-influenza immune response. Taken together, these findings suggest that targeting PLA2G2E could hold potential as a therapeutic strategy for managing influenza virus infections.IMPORTANCEThe influenza virus is a highly transmissible respiratory pathogen that continues to pose a significant public health concern. It effectively evades humoral immune protection conferred by vaccines and natural infection due to its continuous viral evolution through the genetic processes of antigenic drift and shift. Recognition of conserved non-mutable viral epitopes by T cells may provide broad immunity against influenza virus. In this study, we have demonstrated that phospholipase A2 group IIE (PLA2G2E) plays a crucial role in protecting against influenza virus infection through the regulation of T cell responses, while not affecting innate and humoral immune responses. Targeting PLA2G2E could therefore represent a potential therapeutic strategy for managing influenza virus infection.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Pulmón , Infecciones por Orthomyxoviridae , Animales , Ratones , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/virología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Pulmón/virología , Pulmón/inmunología , Pulmón/patología , Humanos , Fosfolipasas A2 Grupo II/genética , Fosfolipasas A2 Grupo II/inmunología , Linfocitos T/inmunología , Ratones Noqueados , Inmunidad Celular , Ratones Endogámicos C57BL , Ratones Transgénicos , Carga Viral , Modelos Animales de Enfermedad , Inmunidad Humoral , Inmunidad Innata , Gripe Humana/inmunología , Gripe Humana/virología , Femenino
2.
Biochem Biophys Res Commun ; 712-713: 149955, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38640737

RESUMEN

We previously demonstrated a positive relation of secretory phospholipase A2 group IIA (sPLA2-IIA) with circulating high-density lipoprotein cholesterol (HDL-C) in patients with coronary artery disease, and sPLA2-IIA increased cholesterol efflux in THP-1 cells through peroxisome proliferator-activated receptor-γ (PPAR-γ)/liver X receptor α/ATP-binding cassette transporter A1 (ABCA1) signaling pathway. The aim of the present study was to examine the role of sPLA2-IIA over-expression on lipid profile in a transgenic mouse model. Fifteen apoE-/- and C57BL/7 female mice received bone marrow transplantation from transgenic SPLA2-IIA mice, and treated with specific PPAR-γ inhibitor GW9662. High fat diet was given after one week of bone marrow transplantation, and animals were sacrificed after twelve weeks. Immunohistochemical staining showed over-expression of sPLA2-IIA protein in the lung and spleen. The circulating level of HDL-C, but not that of low-density lipoprotein cholesterol (LDL-C), total cholesterol, or total triglyceride, was increased by sPLA2-IIA over-expression, and was subsequently reversed by GW9662 treatment. Over-expression of sPLA2-IIA resulted in augmented expression of cholesterol transporter ABCA1 at mRNA level in the aortas, and at protein level in macrophages, co-localized with macrophage specific antigen CD68. GW9662 exerted potent inhibitory effects on sPLA2-IIA-induced ABCA1 expression. Conclusively, we demonstrated the effects of sPLA2-IIA on circulating HDL-C level and the expression of ABCA1, possibly through regulation of PPAR-γ signaling in transgenic mouse model, that is in concert with the conditions in patients with coronary artery disease.


Asunto(s)
Transportador 1 de Casete de Unión a ATP , Molécula CD68 , Ratones Endogámicos C57BL , Ratones Transgénicos , Animales , Transportador 1 de Casete de Unión a ATP/metabolismo , Transportador 1 de Casete de Unión a ATP/genética , Femenino , Ratones , Fosfolipasas A2 Grupo II/metabolismo , Fosfolipasas A2 Grupo II/genética , PPAR gamma/metabolismo , HDL-Colesterol/sangre , HDL-Colesterol/metabolismo , Pulmón/metabolismo , Pulmón/patología , Antígenos de Diferenciación Mielomonocítica/metabolismo , Antígenos CD/metabolismo , Antígenos CD/genética , Bazo/metabolismo , Trasplante de Médula Ósea , Humanos , Lípidos/sangre
3.
Cell Mol Biol (Noisy-le-grand) ; 70(1): 226-232, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38372090

RESUMEN

Delirium is a common psychiatric complication of chronic obstructive pulmonary disease (COPD). The relief of delirium is considered one of the beneficial ways to treat COPD. However, there are currently no specific drugs that alleviate delirium in COPD patients. Our research aimed to elucidate the specific mechanisms underlying delirium in COPD mice, while also seeking more effective therapeutic targets. In our study, bioinformatics analysis and qRT PCR were used to identify key factors in the development of delirium in COPD animal models. Open field and elevated plus maze tests were used to detect delirium in mice. Tunel staining and HE staining were used to analyze the apoptosis of mouse hippocampus cells. EdU and CCK-8 experiments were used to analyze PC-12 cells vitality and proliferation. JASPAR online database, dual luciferase reporting experiments, ChIP experiments, and IF staining were used to analyze the interaction between RXRA and PLA2G2A. RXRA is highly expressed in the brain tissue of COPD mice with delirium symptoms. The downregulation of RXRA inhibits the delirium state in COPD mice. This is mainly due to the reduction of endoplasmic reticulum stress and cell apoptosis by inhibiting the expression of RXRA. In addition, we also confirmed that RXRA is a transcription factor of PLA2G2A. RXRA has an inhibitory effect on the expression of PLA2G2A. In vitro experiments have confirmed that inhibition of the RXRA/PLA2G2A axis reduces cell apoptosis, thereby alleviating the occurrence and development of delirium in COPD mice. Inhibition of the RXRA/PLA2G2A axis reduces endoplasmic reticulum stress and cell apoptosis. This process alleviates the development of delirium in COPD mice.


Asunto(s)
Delirio , Fosfolipasas A2 Grupo II , Enfermedad Pulmonar Obstructiva Crónica , Receptor alfa X Retinoide , Animales , Ratones , Apoptosis , Delirio/tratamiento farmacológico , Delirio/metabolismo , Estrés del Retículo Endoplásmico , Fosfolipasas A2 Grupo II/metabolismo , Pulmón/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Receptor alfa X Retinoide/metabolismo
4.
Chem Biol Drug Des ; 103(1): e14429, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38230769

RESUMEN

Considering the therapeutic efficacy of Stachydrine on breast cancer (BC), this study aims to decipher the relevant mechanism. The effects of Stachydrine on BC cell viability, proliferation and apoptosis were firstly investigated. Then, Bioinformatics was applied to sort out the candidate interacting with Stachydrine as well as its expression and downstream target in BC. Relative expressions of genes of interest as well as proliferation- and apoptosis-related factors in BC cells were quantified through quantitative reverse-transcription PCR and western blot as appropriate. As a result, Stachydrine inhibited the proliferation, down-regulated the expressions of proliferating cell nuclear antigen and CyclinD1, enhanced cell cycle arrest and apoptosis, and up-regulated the levels of Cleaved caspase-3 and Cleaved caspase-9 in BC cells. Phospholipase A2 Group IIA (PLA2G2A) was predicted as the candidate interacting with Stachydrine and to be lowly expressed in BC. PLA2G2A silencing reversed while PLA2G2A overexpression reinforced the effects of Stachydrine. Decorin (DCN) was the downstream target of PLA2G2A and also lowly expressed in BC. PLA2G2A silencing counteracted yet overexpressed PLA2G2A strengthened the promoting effects of Stachydrine on DCN level. Collectively, Stachydrine inhibits the growth of BC cells to promote cell cycle arrest and apoptosis via PLA2G2A/DCN axis.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Prolina/análogos & derivados , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Apoptosis , Puntos de Control del Ciclo Celular , Proliferación Celular , Línea Celular Tumoral , Fosfolipasas A2 Grupo II , Decorina/farmacología
5.
Molecules ; 28(18)2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37764293

RESUMEN

Secreted phospholipases A2 are snake-venom proteins with many biological activities, notably anti-tumor activity. Phospholipases from the same snake type but different geographical locations have shown similar biochemical and biological activities with minor differences in protein sequences. Thus, the discovery of a new phospholipase A2 with unique characteristics identified in a previously studied venom could suggest the origins of these differences. Here, a new Group II secreted phospholipase A2 (Cc-PLA2-II) from the snake venom of Saudi Cerastes cerastes gasperetti was isolated and characterized. The purified enzyme had a molecular weight of 13.945 kDa and showed high specific activity on emulsified phosphatidylcholine of 1560 U/mg at pH 9.5 and 50 °C with strict calcium dependence. Interestingly, stability in extreme pH and high temperatures was observed after enzyme incubation at several pH levels and temperatures. Moreover, a significant dose-dependent cytotoxic anti-tumor effect against six human cancer cell lines was observed with concentrations of Cc-PLA2 ranging from 2.5 to 8 µM. No cytotoxic effect on normal human umbilical-vein endothelial cells was noted. These results suggest that Cc-PLA2-II potentially has angiogenic activity of besides cytotoxicity as part of its anti-tumor mechanism. This study justifies the inclusion of this enzyme in many applications for anticancer drug development.


Asunto(s)
Antineoplásicos , Viperidae , Animales , Humanos , Fosfolipasas A2 Grupo II , Arabia Saudita , Fosfolipasas A2/farmacología , Fosfolipasas A2/química , Fosfolipasas , Venenos de Víboras/farmacología , Venenos de Víboras/química , Antineoplásicos/farmacología
6.
Life Sci ; 331: 122071, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37673297

RESUMEN

AIMS: Idiopathic pulmonary fibrosis (IPF) is a severe pulmonary interstitial pneumonia. Our study focuses on the role of PLA2 enzyme in the IPF to explore a more effective diagnosis and treatment mechanism of IPF. MAIN METHODS: Transcriptome data of IPF from GEO database and bleomycin-induced pulmonary fibrosis mice were analyzed to identify PLA2 enzyme and their metabolite, lysophosphatidylcholines 18:0, in IPF. Based on PLA2G2A and PLA2G2D / PLA2G2A-associated cell death genes (PCDs), the consensus clustering analysis was used to identify the subtypes of IPF and the correlation between PLA2G2A and prognosis was analyzed. The machine learning (ML) models and artificial neural network (ANN) model was used to validate the diagnostic accuracy of PLA2s and PCDs in diagnosing IPF. The gene and protein expression of NLRP3, GSDMD, and CASP-1 was estimated in recombinant PLA2G2A protein induced MLE-12 cells. KEY FINDINGS: The expression of PLA2G2D, PLA2G2A, and LPC18 significantly changed in IPF. Furtherly, PLA2G2A has a significant correlation with poor patient prognosis, which could predict the 2 or 3-years mortality rates of IPF. Two subtypes of IPF patients, identified based on PCDs, showed significant different immunoinfiltration. Recombinant PLA2G2A protein could induce the pyrotosis in the MLE-12 cell. The generalized linear model and ANN model of PLA2s or PCDs accurate diagnosis IPF. SIGNIFICANCE: PLA2G2A is the most robustly associated gene with IPF among the PLA2s, which demonstrates a potential in diagnosing and prognostic value in IPF, and provides a foundation for further understanding and breakthroughs in IPF diagnosis and treatment.


Asunto(s)
Fibrosis Pulmonar Idiopática , Animales , Humanos , Ratones , Bleomicina , Caspasa 1 , Muerte Celular , Análisis por Conglomerados , Fosfolipasas A2 Grupo II , Fibrosis Pulmonar Idiopática/genética
7.
Biochem Biophys Res Commun ; 677: 98-104, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37566923

RESUMEN

Breast cancer is the second most cancer worldwide in females. The primary factor responsible for tumor recurrence is the presence of breast cancer stem cells (BCSCs), which escape the chemo-radiotherapy. In this study, we have investigated the role of Secretory phospholipase-A2 Group 2A (sPLA2-IIA) that is overexpressed in BCSCs of MCF7 and MDA-MB-231 breast cancer cell lines. Further, overexpression of sPLA2-IIA revealed an increased EGFR/JNK/c-JUN/c-FOS signaling in BCSCs, while sPLA2-IIA knockdown significantly reduced the percentage of BCSCs and decreased signaling in both the cell lines. Importantly, sPLA2-IIA knockdown showed differentiation of BCSCs. Strikingly, PET imaging showed a decreased metastatic potential of BCSCs. Our study revealed a novel role of sPLA2-IIA in regulating BCSCs, which play a crucial role in regulating the differentiation and metastatic potential of BCSCs.


Asunto(s)
Neoplasias de la Mama , Fosfolipasas A2 Secretoras , Femenino , Humanos , Fosfolipasas A2 Secretoras/genética , Fosfolipasas , Recurrencia Local de Neoplasia , Diferenciación Celular , Células Madre Neoplásicas , Fosfolipasas A2 Grupo II/genética
8.
Toxins (Basel) ; 15(7)2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37505708

RESUMEN

Host molecules with antimicrobial properties belong to a large family of mediators including type-IIA secreted phospholipase A2 (sPLA2-IIA). The latter is a potent bactericidal agent with high selectivity against Gram-positive bacteria, but it may also play a role in modulating the host inflammatory response. However, several pathogen-associated molecular patterns (PAMPs) or toxins produced by pathogenic bacteria can modulate the levels of sPLA2-IIA by either inducing or inhibiting its expression in host cells. Thus, the final sPLA2-IIA concentration during the infection process is determined by the orchestration between the levels of toxins that stimulate and those that downregulate the expression of this enzyme. The stimulation of sPLA2-IIA expression is a process that participates in the clearance of invading bacteria, while inhibition of this expression highlights a mechanism by which certain bacteria can subvert the immune response and invade the host. Here, we will review the major functions of sPLA2-IIA in the airways and the role of bacterial toxins in modulating the expression of this enzyme. We will also summarize the major mechanisms involved in this modulation and the potential consequences for the pulmonary host response to bacterial infection.


Asunto(s)
Toxinas Bacterianas , Fosfolipasas A2 Secretoras , Antibacterianos/farmacología , Fosfolipasas A2 Grupo II
9.
Cancer Lett ; 558: 216095, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36796670

RESUMEN

Our previous research defined a novel metabolic cancer associated fibroblasts subset (meCAFs) enriched in loose-type pancreatic ductal adenocarcinoma (PDAC) and related to CD8+ T cells accumulation. Consistently, the abundance of meCAFs was associated with poor prognosis but better immunotherapy responses in PDAC patients. However, the metabolic characteristic of meCAFs and its cross-talk with CD8+ T cells remain to be elucidated. In this study, we identified PLA2G2A as a marker of meCAFs. In particular, the abundance of PLA2G2A+ meCAFs was positively related to the accumulation of total CD8+ T cells and negatively correlated with clinical outcomes of PDAC patients and infiltration of intratumoral CD8+ T cells. We demonstrated that PLA2G2A+ meCAFs substantially attenuated the antitumor ability of tumor infiltrating CD8+ T cells and facilitated tumor immune escape in PDAC. Mechanistically, PLA2G2A regulated the function of CD8+ T cells as a pivotal soluble mediator via MAPK/Erk and NF-κB signaling pathways. In conclusion, our study identified the unrecognized role of PLA2G2A+ meCAFs in promoting tumor immune escape by impeding the antitumor immune function of CD8+ T cells, and strongly suggested PLA2G2A as a promising biomarker and therapeutic target for immunotherapy in PDAC.


Asunto(s)
Fibroblastos Asociados al Cáncer , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Linfocitos T Citotóxicos/metabolismo , Fibroblastos Asociados al Cáncer/metabolismo , Linfocitos T CD8-positivos , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/patología , Inmunidad , Microambiente Tumoral , Fosfolipasas A2 Grupo II , Neoplasias Pancreáticas
10.
Immunol Res ; 71(1): 70-82, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36385678

RESUMEN

High levels of human group IIA secreted phospholipase A2 (hGIIA) have been associated with various inflammatory disease conditions. We have recently shown that hGIIA activity and concentration are increased in the plasma of patients with hereditary angioedema due to C1-inhibitor deficiency (C1-INH-HAE) and negatively correlate with C1-INH plasma activity. In this study, we analyzed whether the presence of both hGIIA and C1-INH impairs their respective function on immune cells. hGIIA, but not recombinant and plasma-derived C1-INH, stimulates the production of IL-6, CXCL8, and TNF-α from peripheral blood mononuclear cells (PBMCs). PBMC activation mediated by hGIIA is blocked by RO032107A, a specific hGIIA inhibitor. Interestingly, C1-INH inhibits the hGIIA-induced production of IL-6, TNF-α, and CXCL8, while it does not affect hGIIA enzymatic activity. On the other hand, hGIIA reduces the capacity of C1-INH at inhibiting C1-esterase activity. Spectroscopic and molecular docking studies suggest a possible interaction between hGIIA and C1-INH but further experiments are needed to confirm this hypothesis. Together, these results provide evidence for a new interplay between hGIIA and C1-INH, which may be important in the pathophysiology of hereditary angioedema.


Asunto(s)
Angioedemas Hereditarios , Proteína Inhibidora del Complemento C1 , Fosfolipasas A2 Grupo II , Humanos , Interleucina-6 , Leucocitos Mononucleares , Simulación del Acoplamiento Molecular , Factor de Necrosis Tumoral alfa , Proteína Inhibidora del Complemento C1/química , Proteína Inhibidora del Complemento C1/metabolismo , Fosfolipasas A2 Grupo II/química , Fosfolipasas A2 Grupo II/metabolismo
11.
Int J Mol Sci ; 23(19)2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36233022

RESUMEN

Oncogenic K-ras is often activated in pancreatic ductal adenocarcinoma (PDAC) due to frequent mutation (>90%), which drives multiple cellular processes, including alterations in lipid metabolism associated with a malignant phenotype. However, the role and mechanism of the altered lipid metabolism in K-ras-driven cancer remains poorly understood. In this study, using human pancreatic epithelial cells harboring inducible K-rasG12D (HPNE/K-rasG12D) and pancreatic cancer cell lines, we found that the expression of phospholipase A2 group IIA (PLA2G2A) was upregulated by oncogenic K-ras. The elevated expression of PLA2G2A was also observed in pancreatic cancer tissues and was correlated with poor survival of PDAC patients. Abrogation of PLA2G2A by siRNA or by pharmacological inhibition using tanshinone I significantly increased lipid peroxidation, reduced fatty acid synthase (FASN) expression, and impaired mitochondrial function manifested by a decrease in mitochondrial transmembrane potential and a reduction in ATP production, leading to the inhibition of cancer cell proliferation. Our study suggests that high expression of PLA2G2A induced by oncogenic K-ras promotes cancer cell survival, likely by reducing lipid peroxidation through its ability to facilitate the removal of polyunsaturated fatty acids from lipid membranes by enhancing the de novo fatty acid synthesis and energy metabolism to support cancer cell proliferation. As such, PLA2G2A might function as a downstream mediator of K-ras and could be a potential therapeutic target.


Asunto(s)
Carcinoma Ductal Pancreático , Fosfolipasas A2 Grupo II , Neoplasias Pancreáticas , Adenosina Trifosfato/metabolismo , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Metabolismo Energético , Ácidos Grasos , Fosfolipasas A2 Grupo II/metabolismo , Humanos , Lípidos , Mutación , Hormonas Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , ARN Interferente Pequeño/metabolismo , Neoplasias Pancreáticas
12.
Sci Rep ; 12(1): 14899, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-36050343

RESUMEN

Newborns require early generation of effective innate immunity as a primary physiological mechanism for survival. The neonatal Lin28+Let7- developmental pathway allows increased generation of Th2-type cells and B1a (B-1 B) cells compared to adult cells and long-term maintenance of these initially generated innate cells. For initial B1a cell growth from the neonatal to adult stage, Th2-type IL-5 production from ILC2s and NKT2 cells is important to increase B1a cells. The Th17 increase is dependent on extracellular bacteria, and increased bacteria leads to lower Th2-type generation. Secreted group IIA-phospholipase A2 (sPLA2-IIA) from the Pla2g2a gene can bind to gram-positive bacteria and degrade bacterial membranes, controlling microbiota in the intestine. BALB/c mice are Pla2g2a+, and express high numbers of Th2-type cells and B1a cells. C57BL/6 mice are Pla2g2a-deficient and distinct from the SLAM family, and exhibit fewer NKT2 cells and fewer B1a cells from the neonatal to adult stage. We found that loss of Pla2g2a in the BALB/c background decreased IL-5 from Th2-type ILC2s and NKT2s but increased bacterial-reactive NKT17 cells and MAIT cells, and decreased the number of early-generated B1a cells and MZ B cells and the CD4/CD8 T cell ratio. Low IL-5 by decreased Th2-type cells in Pla2g2a loss led to low early-generated B1a cell growth from the neonatal to adult stage. In anti-thymocyte/Thy-1 autoreactive µκ transgenic (ATAµκ Tg) Pla2g2a+ BALB/c background C.B17 mice generated NKT2 cells that continuously control CD1d+ B1 B cells through old aging and lost CD1d in B1 B cells generating strong B1 ATA B cell leukemia/lymphoma. Pla2g2a-deficient ATAµκTg C57BL/6 mice suppressed the initial B1a cell increase, with low/negative spontaneous leukemia/lymphoma generation. These data confirmed that the presence of Pla2g2a to control bacteria is important to allow the neonatal to adult stage. Pla2g2a promotes innate Th2-type immunity lymphocytes to increase early generated B1a cells.


Asunto(s)
Subgrupos de Linfocitos B , Fosfolipasas A2 Grupo II , Inmunidad Innata , Células Th2 , Animales , Subgrupos de Linfocitos B/metabolismo , Fosfolipasas A2 Grupo II/genética , Fosfolipasas A2 Grupo II/metabolismo , Interleucina-5 , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Células Th17 , Células Th2/metabolismo
13.
Toxicon ; 210: 123-131, 2022 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-35248586

RESUMEN

Myotoxin-II, a phospholipase A2 (PLA2)-like protein found in Bothrops asper venom, causes rapid necrosis of muscle fibers in spite of lacking enzymatic activity. This toxic action maps to its C-terminal region, within a segment known as "115-129" (consensus numbering) that displays a combination of cationic and hydrophobic amino acids, capable of destabilizing membranes. Although myotoxin-II is found in B. asper from both the Caribbean and Pacific regions of Costa Rica, this work shows that in the latter, position 124 is occupied by phenylalanine, instead of leucine reported for the Caribbean variant (UniProt P24605), thus solving the ambiguity described in the original sequencing of this toxin. A comparative inspection of sequences in the C-terminal region of 70 PLA2-like proteins showed that, with few exceptions, position 124 is occupied by either leucine or phenylalanine with equal frequencies. In line with earlier observations on primary and three-dimensional structural data, this comparison supports the notion that the disruptive mechanism of PLA2-like myotoxins toward membranes is not dependent on a fixed amino acid sequence motif across members of this subfamily, but instead on a spatial array of physicochemical properties which can be provided by variable combinations of cationic and hydrophobic residues. This plasticity bears resemblance to features of many antimicrobial peptides acting upon membranes. From a practical point of view, it is recommended to define the identity of the many isoforms of PLA2s and PLA2-like proteins found in viperid venoms by relying on the accurate determination of their intact mass, as these proteins are not known to present post-translational modifications.


Asunto(s)
Bothrops , Venenos de Crotálidos , Secuencia de Aminoácidos , Animales , Bothrops/metabolismo , Venenos de Crotálidos/toxicidad , Fosfolipasas A2 Grupo II , Espectrometría de Masas , Neurotoxinas/toxicidad , Fosfolipasas A2/metabolismo , Proteínas de Reptiles/metabolismo
14.
Biomolecules ; 12(2)2022 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-35204758

RESUMEN

Phospholipases A2 (PLA2) represent a superfamily of enzymes widely distributed in living organisms, with a broad spectrum of pharmacological activities and therapeutic potential. Anti-angiogenic strategies have become one of the main tools in fighting cancer. In this sense, the present work reports the inhibition of tumor angiogenesis induced by Asp-49 BthTX-II using in vitro, ex vivo and in vivo approaches. We demonstrate that BthTx-II inhibited cell adhesion, proliferation, and migration of human umbilical vein endothelial cells (HUVEC), as well as caused a reduction in the levels of endothelial growth factor (VEGF) during in vitro angiogenesis assays. BthTx-II was also able to inhibit the sprouting angiogenic process, by the ex vivo germination assay of the aortic ring; in addition, this toxin inhibited the migration and proliferation of HUVEC in co-culture with triple-negative breast cancer cells (e.g., MDA-MB-231 cells). Finally, in vivo tumor suppression and anti-angiogenic activities were analyzed using MDA-MB-231 cells with Matrigel injected into the chorioallantoic membrane of chicken embryo (CAM) for 7 days treatment with BthTx-II, showing a considerable reduction in vessel caliber, on the size and weight of tumors. Together, these results suggest an important antiangiogenic and antitumor role for BthTx-II, as a potential prototype for the development of new tools and antitumor drugs in cancer therapy.


Asunto(s)
Bothrops , Venenos de Crotálidos , Neoplasias de la Mama Triple Negativas , Animales , Bothrops/metabolismo , Embrión de Pollo , Venenos de Crotálidos/farmacología , Fosfolipasas A2 Grupo II , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Fosfolipasas A2/metabolismo , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico
15.
JCI Insight ; 7(2)2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35076024

RESUMEN

Besides promoting inflammation by mobilizing lipid mediators, group IIA secreted phospholipase A2 (sPLA2-IIA) prevents bacterial infection by degrading bacterial membranes. Here, we show that, despite the restricted intestinal expression of sPLA2-IIA in BALB/c mice, its genetic deletion leads to amelioration of cancer and exacerbation of psoriasis in distal skin. Intestinal expression of sPLA2-IIA is reduced after treatment with antibiotics or under germ-free conditions, suggesting its upregulation by gut microbiota. Metagenome, transcriptome, and metabolome analyses have revealed that sPLA2-IIA deficiency alters the gut microbiota, accompanied by notable changes in the intestinal expression of genes related to immunity and metabolism, as well as in the levels of various blood metabolites and fecal bacterial lipids, suggesting that sPLA2-IIA contributes to shaping of the gut microbiota. The skin phenotypes in Pla2g2a-/- mice are lost (a) when they are cohoused with littermate WT mice, resulting in the mixing of the microbiota between the genotypes, or (b) when they are housed in a more stringent pathogen-free facility, where Pla2g2a expression in WT mice is low and the gut microbial compositions in both genotypes are nearly identical. Thus, our results highlight a potentially new aspect of sPLA2-IIA as a modulator of gut microbiota, perturbation of which affects distal skin responses.


Asunto(s)
Microbioma Gastrointestinal/inmunología , Fosfolipasas A2 Grupo II/metabolismo , Psoriasis , Neoplasias Cutáneas , Animales , Carcinogénesis/inmunología , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/inmunología , Inflamación/microbiología , Ratones , Ratones Endogámicos BALB C , Patología Molecular/métodos , Psoriasis/inmunología , Psoriasis/microbiología , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/microbiología
16.
JCI Insight ; 7(2)2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35076027

RESUMEN

Secreted phospholipase A2-IIA (sPLA2-IIA) hydrolyzes phospholipids to liberate lysophospholipids and fatty acids. Given its poor activity toward eukaryotic cell membranes, its role in the generation of proinflammatory lipid mediators is unclear. Conversely, sPLA2-IIA efficiently hydrolyzes bacterial membranes. Here, we show that sPLA2-IIA affects the immune system by acting on the intestinal microbial flora. Using mice overexpressing transgene-driven human sPLA2-IIA, we found that the intestinal microbiota was critical for both induction of an immune phenotype and promotion of inflammatory arthritis. The expression of sPLA2-IIA led to alterations of the intestinal microbiota composition, but housing in a more stringent pathogen-free facility revealed that its expression could affect the immune system in the absence of changes to the composition of this flora. In contrast, untargeted lipidomic analysis focusing on bacteria-derived lipid mediators revealed that sPLA2-IIA could profoundly alter the fecal lipidome. The data suggest that a singular protein, sPLA2-IIA, produces systemic effects on the immune system through its activity on the microbiota and its lipidome.


Asunto(s)
Artritis , Fenómenos Fisiológicos Bacterianos/inmunología , Microbioma Gastrointestinal/fisiología , Fosfolipasas A2 Grupo II/metabolismo , Metabolismo de los Lípidos/inmunología , Animales , Animales Modificados Genéticamente , Artritis/inmunología , Artritis/microbiología , Humanos , Fenómenos del Sistema Inmunológico , Lipidómica/métodos , Ratones , Modelos Animales , Patología Molecular/métodos , Transgenes
17.
Gene ; 809: 146014, 2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-34655722

RESUMEN

SIMPLE SUMMARY: As a member of genetic polymorphism, copy number variation has been a commonly used method in the world for investigating effect of genetic polymorphism on gene expression. Effect of genetic polymorphism made on livestock development has been more and more important in beef cattle molecular breeding. The characteristics of Chinese cattle are excellent meat quality, tolerant to rough feeding, good environmental adaptability and so on. But there are some obvious weaknesses still exist in the process of cattle growth and development, such as weak hindquarters and growth slowly. To improve the growth performance and market competitiveness of Chinese cattle, a lot of studies have been made about finding and investigating effective molecular marker. In this study, Q-PCR and data association analysis were used for PLA2G2A gene copy number variation detection and related effect analysis in Chinese cattle. Results showed that PLA2G2A gene has a significant effect on two breeds of Chinese cattle on growth traits, which could be a basic materials and effective information of cattle molecular markers breeding. PLA2G2A, member of secreted phospholipases A2 (sPLA2) in superfamily of phospholipase A2, could catalyze the process of glycerophospholipids hydrolysis from position of sn-2 acyl with the release of free fatty acids and lysophospholipids. Researches about PLA2G2A gene are mostly focus on disease, including tumors and diabetes, the number of study occurred on animal breeding is weak. In this study, blood samples were collected from five breeds of Chinese cattle (Qingchuan cattle, Xianan cattle, Yunling cattle, Pinan cattle and Guyuan cattle) for PLA2G2A gene CNV type detection. SPSS 20.0 software and method of ANOVA were used to analyzed the association between types of CNV and growth traits. Results reveal that the distribution of different copy number types in different cattle breeds is different. In QC, XN and GY cattle, the frequencies of Deletion and Duplication are about 40%; in YL cattle, the frequency of Deletion type exceeds 60%; in PN cattle, the frequency of Duplication is closed to 80%. Association analysis indicate that CNV of PLA2G2A gene showed a positive effect in cattle growth: in QC cattle, Chest depth with Normal type copy number possess a increased trend (P < 0.05); individuals with Deletion type copy number have better performance on Height at sacrum, Heart girth and Body height in GY cattle (P < 0.05). The functional role and molecular mechanism of PLA2G2A gene in animal growth and development are still unclear, and it is necessary for processing a further research. This research aims to provide basic materials for molecular breeding of Chinese cattle.


Asunto(s)
Bovinos/genética , Fosfolipasas A2 Grupo II/genética , Animales , Peso Corporal/genética , Bovinos/crecimiento & desarrollo , China , Variaciones en el Número de Copia de ADN , Femenino , Regulación del Desarrollo de la Expresión Génica , Frecuencia de los Genes
18.
Nat Commun ; 12(1): 7222, 2021 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-34893640

RESUMEN

Multi-system Inflammatory Syndrome in Children (MIS-C) is a major complication of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection in pediatric patients. Weeks after an often mild or asymptomatic initial infection with SARS-CoV-2 children may present with a severe shock-like picture and marked inflammation. Children with MIS-C present with varying degrees of cardiovascular and hyperinflammatory symptoms. Here we perform a comprehensive analysis of the plasma proteome of more than 1400 proteins in children with SARS-CoV-2. We hypothesize that the proteome would reflect heterogeneity in hyperinflammation and vascular injury, and further identify pathogenic mediators of disease. We show that protein signatures demonstrate overlap between MIS-C, and the inflammatory syndromes macrophage activation syndrome (MAS) and thrombotic microangiopathy (TMA). We demonstrate that PLA2G2A is an important marker of MIS-C that associates with TMA. We find that IFNγ responses are dysregulated in MIS-C patients, and that IFNγ levels delineate clinical heterogeneity.


Asunto(s)
COVID-19/complicaciones , Endotelio Vascular/fisiopatología , Interferón gamma/inmunología , Proteoma , Síndrome de Respuesta Inflamatoria Sistémica/patología , Biomarcadores , COVID-19/metabolismo , COVID-19/patología , Estudios de Casos y Controles , Quimiocina CXCL9 , Niño , Fosfolipasas A2 Grupo II , Humanos , Inflamación , Interleucina-10 , Proteómica , Síndrome de Respuesta Inflamatoria Sistémica/metabolismo , Enfermedades Vasculares
19.
Molecules ; 26(23)2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34885848

RESUMEN

Phospholipase A2 (PLA2) enzymes were first recognized as an enzyme activity class in 1961. The secreted (sPLA2) enzymes were the first of the five major classes of human PLA2s to be identified and now number nine catalytically-active structurally homologous proteins. The best-studied of these, group IIA sPLA2, has a clear role in the physiological response to infection and minor injury and acts as an amplifier of pathological inflammation. The enzyme has been a target for anti-inflammatory drug development in multiple disorders where chronic inflammation is a driver of pathology since its cloning in 1989. Despite intensive effort, no clinically approved medicines targeting the enzyme activity have yet been developed. This review catalogues the major discoveries in the human group IIA sPLA2 field, focusing on features of enzyme function that may explain this lack of success and discusses future research that may assist in realizing the potential benefit of targeting this enzyme. Functionally-selective inhibitors together with isoform-selective inhibitors are necessary to limit the apparent toxicity of previous drugs. There is also a need to define the relevance of the catalytic function of hGIIA to human inflammatory pathology relative to its recently-discovered catalysis-independent function.


Asunto(s)
Fosfolipasas A2 Grupo II/metabolismo , Desarrollo de Medicamentos , Fosfolipasas A2 Grupo II/antagonistas & inhibidores , Fosfolipasas A2 Grupo II/farmacología , Humanos , Neoplasias/diagnóstico , Neoplasias/enzimología , Pronóstico
20.
FASEB J ; 35(10): e21881, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34478587

RESUMEN

Group IIA secreted phospholipase A2 (PLA2G2A) hydrolyzes glycerophospholipids at the sn-2 position resulting in the release of fatty acids and lysophospholipids. C57BL/6 mice do not express Pla2g2a due to a frameshift mutation (wild-type [WT] mice). We previously reported that transgenic expression of human PLA2G2A in C57BL/6 mice (IIA+ mice) protects against weight gain and insulin resistance, in part by increasing total energy expenditure. Additionally, we found that brown and white adipocytes from IIA+ mice have increased expression of mitochondrial uncoupling markers, such as uncoupling protein 1 (UCP1), peroxisome proliferator-activated receptor-gamma coactivator, and PR domain containing 16, suggesting that the energy expenditure phenotype might be due to an increased thermogenic capacity in adipose tissue. Here, we further characterize the impact of PLA2G2A on thermogenic mechanisms in adipose tissue. Metabolic analysis of WT and IIA+ mice revealed that even when housed within their thermoneutral zone, IIA+ mice have elevated energy expenditure compared to WT littermates. Increased energy expenditure in IIA+ mice is associated with increased citrate synthase activity in brown adipose tissue (BAT) and increased mitochondrial respiration in both brown and white adipocytes. We also observed that direct addition of recombinant PLA2G2A enzyme to in vitro cultured adipocytes results in the marked induction of UCP1 protein expression. Finally, we report that PLA2G2A induces the expression of numerous transcripts related to energy substrate transport and metabolism in BAT, suggestive of an increase in substrate flux to fuel BAT activity. These data demonstrate that PLA2G2A enhances adipose tissue thermogenesis, in part, through elevated substrate delivery and increased mitochondrial content in BAT.


Asunto(s)
Tejido Adiposo Pardo/fisiopatología , Metabolismo Energético , Fosfolipasas A2 Grupo II/fisiología , Mitocondrias/patología , Termogénesis , Proteína Desacopladora 1/metabolismo , Tejido Adiposo Blanco/fisiopatología , Animales , Transporte Biológico , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mitocondrias/metabolismo
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