Phospholipase D regulates ferroptosis signal transduction in mouse spleen hypoxia response

High-altitude hypoxia exposure can lead to phospholipase D-mediated lipid metabolism disorder in spleen tissues and induce ferroptosis. Nonetheless, the key genes underlying hypoxia-induced splenic phospholipase D and the ferroptosis pathway remain unclear. This study aimed to establish a hypoxia animal model. Combined transcriptomic and proteomic analyses showed that 95 predicted target genes (proteins) were significantly differentially expressed under hypoxic conditions. Key genes in phospholipase D and ferroptosis pathways under hypoxic exposure were identified by combining Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis techniques. Gene set enrichment analysis (GSEA) showed that the differential gene sets of the phospholipase D and ferroptosis signaling pathways were upregulated in the high-altitude hypoxia group. The genes in the phospholipase D signalling pathway were verified, and the expression levels of KIT and DGKG were upregulated in spleen tissues under hypoxic exposure. Subsequently, the mRNA and protein expression levels of genes from the exogenous pathway such as TFRC, SLC40A1, SLC7A11, TRP53, and FTH1 and those from the endogenous pathway such as GPX4, HMOX1, and ALOX15 differentials in the ferroptosis signalling pathway were verified, and the results indicated significant differential expression. In summary, exposure to high-altitude hypoxia mediated phospholipid metabolism disturbance through the phospholipase D signalling pathway and further induced ferroptosis, leading to splenic injury.

Research Advance of Chinese Medicine in Treating Atherosclerosis: Focus on Lipoprotein-Associated Phospholipase A2 / 中国结合医学杂志

As a serious cardiovascular disease, atherosclerosis (AS) causes chronic inflammation and oxidative stress in the body and poses a threat to human health. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is a member of the phospholipase A2 (PLA2) family, and its elevated levels have been shown to contribute to AS. Lp-PLA2 is closely related to a variety of lipoproteins, and its role in promoting inflammatory responses and oxidative stress in AS is mainly achieved by hydrolyzing oxidized phosphatidylcholine (oxPC) to produce lysophosphatidylcholine (lysoPC). Moreover, macrophage apoptosis within plaque is promoted by localized Lp-PLA2 which also promotes plaque instability. This paper reviews those researches of Chinese medicine in treating AS via reducing Lp-PLA2 levels to guide future experimental studies and clinical applications related to AS.

Phosphatidic acid-enabled MKL1 contributes to liver regeneration: Translational implication in liver failure

Liver regeneration following injury aids the restoration of liver mass and the recovery of liver function. In the present study we investigated the contribution of megakaryocytic leukemia 1 (MKL1), a transcriptional modulator, to liver regeneration. We report that both MKL1 expression and its nuclear translocation correlated with hepatocyte proliferation in cell and animal models of liver regeneration and in liver failure patients. Mice with MKL1 deletion exhibited defective regenerative response in the liver. Transcriptomic analysis revealed that MKL1 interacted with E2F1 to program pro-regenerative transcription. MAPKAPK2 mediated phosphorylation primed MKL1 for its interaction with E2F1. Of interest, phospholipase d2 promoted MKL1 nuclear accumulation and liver regeneration by catalyzing production of phosphatidic acid (PA). PA administration stimulated hepatocyte proliferation and enhanced survival in a MKL1-dependent manner in a pre-clinical model of liver failure. Finally, PA levels was detected to be positively correlated with expression of pro-regenerative genes and inversely correlated with liver injury in liver failure patients. In conclusion, our data reveal a novel mechanism whereby MKL1 contributes to liver regeneration. Screening for small-molecule compounds boosting MKL1 activity may be considered as a reasonable approach to treat acute liver failure.

An overview of some enzymes from buthid scorpion venoms from Colombia: Centruroides margaritatus, Tityus pachyurus, and Tityus n. sp. aff. metuendus

Background: In Colombia, several species of Buthidae scorpions belonging to the genera Centruroides and Tityus coexist, and their stings are considered life-threatening to humans because of their venom neurotoxins. Despite previous studies focusing on neurotoxins from these scorpion genera, little is known about the enzymes present in their venoms and their relationship with whole venom toxicity. Methods: Here, using proteomic and biochemical protocols the enzymatic activities of the venoms of three Colombian scorpion species, C. margaritatus, T. pachyurus, and T. n. sp. aff. metuendus, were compared to establish the presence and absence of enzymes such as phospholipases, hyaluronidases, and proteases that could be related to venom toxicity. Results: C. margaritatus was positive for hyaluronidases, T. n. sp. aff. metuendus for proteases, and T. pachyurus exhibited activity for all three mentioned enzymes. Conclusion: This information provides valuable insights into the specific enzyme diversity of each species' venom and their potential role in venom toxicity, which could contribute to the development of better treatments and prevention strategies for scorpion envenomation.

Understanding the complexity of Tityus serrulatus venom: A focus on high molecular weight components

Tityus serrulatus scorpion is responsible for a significant number of envenomings in Brazil, ranging from mild to severe, and in some cases, leading to fatalities. While supportive care is the primary treatment modality, moderate and severe cases require antivenom administration despite potential limitations and adverse effects. The remarkable proliferation of T. serrulatus scorpions, attributed to their biology and asexual reproduction, contributes to a high incidence of envenomation. T. serrulatus scorpion venom predominantly consists of short proteins acting as neurotoxins (α and ß), that primarily target ion channels. Nevertheless, high molecular weight compounds, including metalloproteases, serine proteases, phospholipases, and hyaluronidases, are also present in the venom. These compounds play a crucial role in envenomation, influencing the severity of symptoms and the spread of venom. This review endeavors to comprehensively understand the T. serrulatus scorpion venom by elucidating the primary high molecular weight compounds and exploring their potential contributions to envenomation. Understanding these compounds' mechanisms of action can aid in developing more effective treatments and prevention strategies, ultimately mitigating the impact of scorpion envenomation on public health in Brazil.

Actividad antiinflamatoria in vitro de Plantago major L. y Piper aduncum L. sobre la fosfolipasa A2 del veneno de la serpiente Lachesis muta muta / In vitro anti-inflammatory activity of Plantago major L. and Piper aduncum L. on phospholipase A2 from the venom of snake Lachesis muta muta

Objetivo. Evaluar la actividad inhibitoria in vitro de los extractos de Plantago major «llantén» y Piper aduncum «matico» sobre Fosfolipasa A2 (PLA2) del veneno de la serpiente Lachesis muta muta. Materiales y métodos. Esta investigación fue de tipo explicativa con diseño experimental. Se recolectaron hojas de P. major y P. aduncum en la provincia de Huarochirí en Lima, Perú. Se prepararon extractos alcohólicos diluidos en agua destilada y se realizaron los ensayos fitoquímicos, la cuantificación de fenoles y flavonoides, la cromatografía de capa fina (CCF) en celulosa y la actividad enzimática con PLA2. Se analizó la capacidad de inhibir la PLA2 con los extractos en estudio y sus fracciones. Para el análisis estadístico se utilizó la prueba de Kruskal Wallis y comparaciones múltiples de Bonferroni. Resultados. Tanto en P. major como en P. aduncum se identificó cualitativamente la presencia de fenoles, flavonoides y taninos; además, P. aduncum presentó saponinas. La inhibición de la actividad de la PLA2 del veneno por el extracto total de P. major fue del 45,3%, y sus fracciones mostraron valores de inhibición: LLF-1 con 31,1%, LLF-2 con 66,3% y LLF-3 con 65,5%. En P. aduncum, los valores de inhibición para el extracto total fueron de 86,9%, y sus fracciones presentaron inhibiciones: MF-1 con 34,3%, MF-2 con 67,1% y MF-3 con 54,9%. El análisis estadístico demostró diferencias significativas en la inhibición de la PLA2 (p=0,009) por los extractos. Conclusión. Los ensayos realizados demostraron una asociación entre el efecto antiinflamatorio de los extractos y la inhibición de la PLA2.

Objective. To evaluate the in vitro inhibitory activity of Plantago major "llantén" and Piper aduncum "matico" extracts on phospholipase A2 (PLA2) from the venom of the snake Lachesis muta muta. Materials and methods. We carried out an explanatory study with experimental design. Leaves of P. major and P. aduncum were collected in the province of Huarochirí in Lima, Peru. Then, we prepared alcoholic extracts diluted in distilled water and conducted phytochemical assays, quantification of phenols and flavonoids, thin layer chromatography (TLC) on cellulose and enzymatic activity with PLA2. The ability to inhibit PLA2 with the extracts under study and their fractions was analyzed. The Kruskal Wallis test and Bonferroni multiple comparisons were used during statistical analysis. Results. Phenols, flavonoids and tannins were qualitatively identified in both P. major and P. aduncum; in addition, P. aduncum presented saponins. The inhibition of PLA2 activity of the venom by the total extract of P. major was 45.3%, and its fractions showed the following inhibition values: 31.1% for LLF-1, 66.3% for LLF-2 and 65.5% for LLF-3. The inhibition values for the total extract of P. aduncum were 86.9%, and its fractions showed the following inhibition rates: 34.3% for MF-1, 67.1% for MF-2 and 54.9% for MF-3. Statistical analysis showed significant differences in the inhibition of PLA2 (p=0.009) by the extracts. Conclusion. The tests demonstrated an association between the anti-inflammatory effect of the extracts and PLA2 inhibition.

Utility of serum anti-phospholipase A2 receptor antibody as a biomarker in membranous nephropathy: An experience from a tertiary care center of Eastern India

Background: Membranous nephropathy (MN) is a pattern of glomerular injury. Exact categorization into primary membranous nephropathy (PMN) or secondary membranous nephropathy (SMN) is essential for treatment. An endogenous podocyte antigen, M-type phospholipase A2 receptor (PLA2R) has been discovered to be involved in the pathogenesis of PMN. Aims and Objectives: In this article, we aimed to analyze renal tissue PLA2R and serum anti-PLA2R antibodies in MN cases and determined the diagnostic utility. Materials and Methods: The study was of prospective type carried out from March 2019 to August 2020. Analysis of cases of MN was performed with PLA2R paraffin immunoflourescence and serum anti-PLA2R antibody ELISA. Results: Overall sensitivity, specificity, PPV, and NPV of serum anti-PLA2R ELISA for PMN was 91.3%, 80%, 75%, and 93.3%, respectively, and of tissue PLA2R staining for PMN was 91.67%, 81.08%, 75.86%, and 93.75%, respectively. There was strong concordance between two methods. In the patients that were followed up, we found baseline serum anti-PLA2R antibody was less in complete remission group than that in non-remission group and the reduction in serum anti-PLA2R antibody was more in complete remission group than that in non-remission group. Conclusion: Routine light and immunofluorescence examination are incapable of giving exact categorical opinion regarding PMN and SMN. Serum anti-PLA2R antibody detection and renal tissue PLA2R analysis are sensitive and specific in detecting PMN. Baseline serum anti-PLA2R antibody and anti-PLA2R antibody quantification trends are related to prognosis of PMN. So they can be incorporated as additional biomarker.

Inhibición de enzimas fosfolipasas A2 de venenos totales de serpientes como estrategia en la búsqueda de nuevos fármacos / Enzyme phospholipase A2 inhibition from snake venoms as strategy to search for new drug

Introducción: Los fármacos antiinflamatorios no esteroideos (AINEs) son ampliamente utilizados para la terapia del dolor, a pesar de sus efectos secundarios que ocurren a nivel renal, estomacal y coagulatorio. Las fosfolipasas A2 (PLA2) presentes en los venenos de serpientes, abejas e incluso en el organismo humano, son responsables de varios procesos fisiológicos y patológicos. Las enzimas hidrolizan fosfolípidos de membrana liberando ácido araquidónico, un precursor de los eicosanoides pro-inflamatorios, los cuales originan mediadores de la inflamación. Objetivo: El propósito de este trabajo es revisar nuevas moléculas capaces de bloquear la escisión de los fosfolípidos de membrana por acción de las PLA2, evitando la formación de mediadores de inflamación. Metodología: Se realizó una revisión bibliográfica de estudios publicados desde 2011 a 2021, que reportan compuestos con actividad inhibitoria frente a PLA2. El potencial de los estudios de relación estructura actividad se discute como estrategia para encontrar compuestos activos ante PLA2. Resultados: Se revisaron 26 estudios que incluyen compuestos naturales y sintéticos y se recopilaron 93 moléculas con actividad inhibitoria, destacando su potencial como inhibidores de PLA2. Conclusiones: La actividad inhibitoria de los compuestos revisados podría estar asociada a los patrones de sustitución en el anillo bencénico de las moléculas. La evaluación de características moleculares relevantes en la inhibición de PLA2 puede guiar a la identificación de candidatos para síntesis de nuevos inhibidores enzimáticos.

Introduction: Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used for pain therapy, despite its side effects in renal, stomach and coagulant systems. Phospholipases A2 (PLA2) enzymes, present in snakes and bees' venoms, and even in the human organism, are responsible for several physiological and pathological processes. These enzymes hydrolyze membrane phospholipids, releasing arachidonic acid, a precursor of pro-inflammatory eicosanoids, which give rise to inflammatory mediators. Objective: The aim of the present work is to review new molecules able to block the cleavage of membrane phospholipids by the action of phospholipases A2, preventing the formation of inflammatory mediators. Methodology: A bibliographic revision from literature published from 2011 to 2021 focused on PLA2 inhibitors was carried out. The potential of structure-activity relationship studies is discussed as a strategy to find active compounds against PLA2. Results: 26 studies including natural and synthetic compounds were reviewed and data from 93 molecules with inhibitory activity were collected, highlighting its potential as PLA2 inhibitors. Conclusion: The inhibitory activity of the reviewed compounds could be associated with the substitution patterns in the benzene ring of the molecules. The evaluation of molecular moieties with relevant capacity to inhibit PLA2 will lead to the identification of candidates for synthesis of new enzymes inhibitors.

Polimorfismo no gene PNPLA3 e o consumo de carne vermelha aumentam o risco de fibrose em pacientes com DHGNA comprovado por biópsia em acompanhamento médico em um centro terciário no Sudoeste do Brasil / Pnpla3 gene polymorphism and red meat consumption increased fibrosis risk in nash biopsy-proven patients under medical follow-up in a tertiary center in southwest brazil

ABSTRACT Background: Recent studies show an increase in nonalcoholic fatty liver disease (NAFLD) in populations with higher consumption of red meat, processed and cooked at high temperatures. On the other hand, the single nucleotide polymorphism rs738409 in the Patatin-like phospholipase domain containing 3 (PNPLA3) gene has been implicated in susceptibility to NAFLD and liver fibrosis. However, the synergistic effect between red meat consumption and the PNPLA3 gene polymorphism in NAFLD has not yet been evaluated. Objective: To evaluate the association between the presence of the polymorphism in the PNPLA3 gene and the consumption of macronutrients, including meat consumption and its cooking method among NAFLD patients. Methods: This was a cross-sectional study with 91 patients diagnosed with NAFLD by liver biopsy with genotyping for the polymorphism in the PNPLA3 gene were included. The consumption of calories and macronutrients was verified using the semi-quantitative food frequency questionnaire and the specific questionnaire on meat consumption. PNPLA3 gene polymorphism was analyzed by real-time polymerase chain reaction (RT-PCR) and anthropometric evaluation was realized. Results: The mean BMI was 32.38±4.58 kg/m² and the waist circumference was 107±10 cm. On liver biopsy, 42% of patients had significant fibrosis (F≥2). The odds ratio of F≥2 was 2.12 for the GG group and 1.54 for the CG group, compared to the CC group. The mean caloric intake was 1170±463.20 kcal/d. The odds ratio in the CC group concerning high red meat consumption in comparison to low consumption was 1.33. For white meat, the odds ratio was 0.8 when comparing high and low intake, also in the CC group. Conclusion: High red meat intake and PNPLA3 gene polymorphism seem to synergistically affect NAFLD and liver fibrosis, requiring confirmation in a larger number of patients and in different populations.

RESUMO Contexto: Estudos recentes mostram um aumento da doença hepática gordurosa não alcoólica (DHGNA) em populações com maior consumo de carne vermelha, processada e cozida em altas temperaturas. Por outro lado, o polimorfismo rs738409 no gene Patatin-like fosfolipase contendo 3 (PNPLA3) tem sido implicado na suscetibilidade à DHGNA e fibrose hepática. No entanto, o efeito sinérgico entre o consumo de carne vermelha e o polimorfismo no gene PNPLA3 na DHGNA ainda não foi avaliado. Objetivo: Avaliar a associação entre a presença do polimorfismo no gene PNPLA3 e o consumo de macronutrientes, incluindo o consumo de carne e seu modo de cozimento em pacientes com DHGNA. Métodos: Realizamos um estudo transversal com 91 pacientes diagnosticados com DHGNA por biópsia hepática e genotipados para o polimorfismo no gene PNPLA3. O consumo de calorias e macronutrientes foi verificado por meio do questionário de frequência alimentar semi-quantitativo (QFA) e do questionário específico sobre consumo de carnes. O polimorfismo no gene PNPLA3 foi analisado por reação em cadeia da polimerase em tempo real (RT-PCR) e a avaliação antropométrica foi realizada. Resultados: O índice de massa corporal médio foi de 32,38±4,58 kg/m² e a circunferência da cintura foi de 107±10 cm. Na biópsia hepática, 42% dos pacientes apresentavam fibrose significativa (F≥2). O odds ratio de F≥2 foi de 2,12 para o grupo GG e 1,54 para o grupo GC, comparado ao grupo CC. A ingestão calórica média foi de 1.170±463,20 kcal/d. O odds ratio para alto consumo de carne vermelha no grupo CC em comparação ao baixo consumo foi de 1,33. Para a carne branca, este valor foi de 0,8 ao comparar o alto e o baixo consumo, também no grupo CC. Conclusão: A alta ingestão de carne vermelha e o polimorfismo no gene PNPLA3 parecem afetar sinergicamente a DHGNA e a fibrose hepática, necessitando de confirmação em maior número de pacientes e em diferentes populações.

Neuroprotective effect and mechanism of cPLA2 inhibitor increases autophagic flux on spinal cord injury / 中国骨伤

OBJECTIVE@#To investigate the mechanism of cytosolic phospholipase A2(cPLA2) inhibitor to improve neurological function after spinal cord injury (SCI).@*METHODS@#Thirty-six 3 months old female SD rats, with body mass (280±20) g, were divided into three groups (n=12):sham group, SCI group, and SCI+ arachidonyl trifluoromethyl ketone(AACOCF3) group. Balloon compression SCI model was established in all three groups. In the sham model group, the spinal cord compression model was created after the balloon was placed without pressure treatment, and the remaining two groups were pressurized with the balloon for 48 h. After successful modeling, rats in the SCI+AACOCF3 group were injected intraperitoneally with AACOCF3, a specific inhibitor of cPLA2. The remaining two groups of rats were injected intraperitoneally with saline. The animals were sacrificed in batches on 7 and 14 days after modeling, respectively. And the damaged spinal cord tissues were sampled for pathomorphological observation, to detect the expression of cPLA2 and various autophagic fluxPrelated molecules and test the recovery of motor function.@*RESULTS@#Spinal cord histomorphometry examination showed that the spinal cord tissue in the sham group was structurally intact, with normal numbers and morphology of neurons and glial cells. In the SCI group, spinal cord tissue fractures with large and prominent spinal cord cavities were seen. In the SCI+AACOCF3 group, the spinal cord tissue was more intact than in the SCI group, with more fused spinal cord cavities, more surviving neurons, and less glial cell hyperplasia. Western blot showed that the sham group had the lowest protein expression of LC3-Ⅱ, Beclin 1, p62, and cPLA2 compared with the SCI and SCI+AACOCF3 groups (P<0.05) and the highest protein expression of LC3-Ⅰ (P<0.05). P62 and cPLA2 expression in the SCI group were higher than in the SCI+AACOCF3 group (P<0.05). Behavioral observations showed that the time corresponding to BBB exercise scores was significantly lower in both the SCI and SCI+AACOCF3 groups than in the sham group (P<0.05). Scores at 3, 7, and 14 days after pressurization were higher in the SCI+AACOCF3 group than in the SCI group (P<0.05).@*CONCLUSION@#cPLA2 inhibitors can reduce neuronal damage secondary to SCI, promote neurological recovery and improve motor function by improving lysosomal membrane permeability and regulating autophagic flux.

Clinical Significance of Thrombospondin Type 1 Domain-Containing 7A and Neural Epidermal Growth Factor-Like 1 Protein in M-Type Phospholipase A2 Receptor-Negative Membranous Nephropathy / 中国医学科学院学报

Objective To investigate the clinical significance of thrombospondin type 1 domain-containing 7A (THSD7A) and neural epidermal growth factor-like 1 protein (NELL1) in phospholipase A2 receptor (PLA2R)-negative membranous nephropathy (MN). Methods A total of 116 PLA2R-negative MN patients treated in Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University from 2014 to 2021 were enrolled in this study.Immunohistochemistry was employed to detect THSD7A and NELL1 in the renal tissue.The pathological characteristics,treatment,and prognosis were compared between positive and negative groups. Results The 116 PLA2R-negative MN patients included 23 THSD7A-positive patients and 9 NELL1-positive patients.One patient was tested positive for both proteins.The THSD7A-positive group showed higher positive rate of IgG4 (P=0.010),more obvious glomerular basement membrane (GBM) thickening (P=0.034),and higher proportion of stage Ⅱ MN and lower proportion of stage I MN (P=0.002) than the THSD7A-negative group.The NELL1-positive group had lower positive rates of C1q and IgG2 (P=0.029,P=0.001),less obvious GBM thickening (P<0.001),more extensive inflammatory cell infiltration (P=0.033),lower proportion of deposits on multi-locations (P=0.001),and lower proportion of atypical MN (P=0.010) than the NELL1-negative group.One patient with THSD7A-positive MN was diagnosed with colon cancer,while none of the NELL1-positive patients had malignancy.Survival analysis suggested that THSD7A-positive MN had worse composite remission (either complete remission or partial remission) of nephrotic syndrome than the negative group (P=0.016),whereas NELL1-positive MN exhibited better composite remission of nephrotic syndrome than the negative group (P=0.015).The MN patients only positive for NELL1 showed better composite remission of nephrotic syndrome than the MN patients only positive for THSD7A (P<0.001). Conclusions THSD7A- and NELL1-positive MN is more likely to be primary MN,and there is no significant malignancy indication.However,it might have a predictive value for the prognosis of MN.

Three cases of obinutuzumab treatment for rituximab-resistant phospholipase A 2 receptor- associated membranous nephropathy / 中华肾脏病杂志

Rituximab is currently used as a first-line therapy for phospholipase A 2 receptor-associated membranous nephropathy due to its good efficacy and safety. Although the remission rate after rituximab treatment is more than 60%, nearly 40% patients still do not respond to treatment. We used obinutuzumab to treat 3 cases of rituximab resistant PLA 2R-associated membranous nephropathy. After the first dose of 1 000 mg with or without additional dose, the amount of anti-PLA 2R antibody and urinary protein decreased significantly and the adverse reactions were mild. The results show that obinutuzumab has a certain therapeutic effect on rituximab resistant PLA 2R-associated membranous nephropathy, but the time of follow-up observation is short and can only be used as individual cases, which needs to be confirmed by a large sample and high-quality prospective cohort study.

Lipoprotein-associated phospholipase A2 combined with D-dimer to fibrinogen ratio to construct a prognostic nomogram model for patients with acute myocardial infarction after percutaneous coronary intervention / 中国医师进修杂志

Objective:To construct acute ST-segment elevation myocardial infarction (STEMI) percutaneous coronary intervention (PCI) by using lipoprotein-associated phospholipase A2 (Lp-PLA2) and D-dimer to fibrinogen ratio (D/F) and other indicators postoperative patient prognosis nomogram model and evaluation of its predictive value.Methods:A total of 291 acute STEMI patients admitted to the BenQ Hospital Affiliated to Nanjing Medical University from January 2017 to January 2020 were retrospectively selected, including but not limited to Lp-PLA2 and D/F, were collected. Receiver operating characteristic (ROC) curve and multivariate Logistic regression were used to analyze the risk factors of death within 90 d after PCI in STEMI patients, and Kaplan-Meier survival curves were drawn to compare the survival of patients in different Lp-PLA2 and D/F groups. The R language software was used to build nomogram model and decision curve.Results:The AUCs of LpPLA2 and D/F for predicting the risk of death from cardiac causes at 90 s after PCI in patients with acute STEMI were 0.896 (95% CI 0.850 to 0.932) and 0.884 (95% CI 0.837 to 0.922), respectively. The values were 59.50 μg/L and 0.46 respectively ( P<0.05); the mortality rates of acute STEMI patients in LpPLA2>59.50 μg/L and D/F>0.46 groups after PCI were higher than those in LpPLA2≤59.50 μg/L group and D/F≤0.46 group ( P<0.05); age (>66 years), left ventricular ejection fraction (LVEF) (≤45%), LpPLA2 (>59.50 μg/L), D/F (>0.46), N-terminal brain natriuretic peptide precursor (>1.55 μg/L) and fasting blood glucose (>7.00 mmol/L) were the risk of death from cardiac causes at 90 d after PCI in patients with acute STEMI ( P<0.05); when the risk thresholds were >0.24, the nomogram model could provide significant additional net clinical benefit. Conclusions:Lp-PLA2 and D/F are closely related to the prognosis of patients with acute STEMI after PCI, and the nomogram model constructed in combination with other clinical indicators can effectively predict the risk of death within 90 d after PCI.

Serum lipoprotein-associated phospholipase A2 level is positively correlated with the recurrence risk of acute ischemic cerebral infarction in hypertensive patients / 南方医科大学学报

OBJECTIVE@#To explore the relationship between serum lipoprotein-associated phospholipase A2 (Lp-PLA2) level and the risk of acute ischemic stroke (AIS) recurrence in hypertensive patients.@*METHODS@#This retrospective case-control study was conducted among 211 hypertensive patients with AIS treated in Foshan First People's Hospital, including 35 patients with recurrence of AIS during the 1-year follow-up as confirmed by head CT/MR. In the overall patients, 60 had grade 1 hypertension (including 5 recurrent cases), 76 had grade 2 hypertension (with 11 recurrent cases), and 75 had grade 3 hypertension (with 19 recurrent cases). Univariate analysis, multivariate logistic regression analysis, trend analysis, and smooth curve fitting analysis were performed to explore the correlation between serum Lp-PLA2 level within 24 h after admission and the risk of AIS recurrence. The predictive efficacy of serum Lp-PLA2 level for AIS recurrence in different hypertension grades was evaluated using ROC curve analysis.@*RESULTS@#Serum Lp-PLA2 level, age, NIHSS score at admission, mRS scores at 7 days, homocysteine level and smoking status differed significantly between patients with and without AIS recurrence (P < 0.05). After adjustment for confounding factors, multivariate regression analysis showed that the highest tertile of Lp-PLA2 level was associated with a 4.13-fold increase of AIS recurrence risk compared with the lowest tertile (OR=5.13, 95% CI: 1.35-19.40), and each 1 ng/mL increase of Lp-PLA2 level was associated with a 1% increase of AIS recurrence risk (OR= 1.01, 95% CI: 1.01-1.02). Serum Lp-PLA2 level was shown to positively correlate with AIS recurrence risk, and in patients with grade 3 hypertension, its areas under the ROC curve for predicting AIS recurrence was 0.869 with a specificity of 0.893 and a sensitivity of 0.737.@*CONCLUSION@#Serum Lp-PLA2 concentration is an independent risk factor and potentially an effective predictor for AIS recurrence in patients with grade 3 hypertension.

Correlation between smoking and serum lipoprotein-associated phospholipase A2 level in overweight and obese men / 中南大学学报(医学版)

OBJECTIVES@#Lipoprotein-associated phospholipase A2 (Lp-PLA2) is a vaso-specific inflammatory marker that exacerbates atherosclerotic through inflammatory responses. It can be used to predict the occurrence of adverse cardiovascular events and to assess the residual risk of cardiovascular diseases. This study aims to investigate the correlation between smoking and serum Lp-PLA2 levels in overweight and obese men, and to provide evidence for preventing the cardiovascular diseases.@*METHODS@#Male subjects, who participated in health examination at the Health Management Center, Third Xiangya Hospital, Central South University from May 1, 2020 to April 30, 2021, were selected. The smoking status and other information were collected by the Self-test Scale of Physical Examination. According to the smoking status, they were divided into a never-smoking group, a current smoking group, a quit smoking group and a passive smoking group. According to the daily smoking amount, the current smoking subjects were divided into a <10 cigarettes group, a 10 to 20 cigarettes group, a 21 to 30 cigarettes group, and a >30 cigarettes group. According to the smoking years, the current smoking subjects were divided into a <5 years group, a 5 to 10 years group, a 11 to 20 years group, and a >20 years group.Serum Lp-PLA2 levels and other clinical indexes in different smoking groups were measured and compared, the correlation between smoking and serum Lp-PLA2 levels in overweight and obese men was analyzed by logistic regression analysis.@*RESULTS@#Serum Lp-PLA2 levels were significantly different between the never-smoking group and the current smoking group (P<0.05). Logistic regression analysis showed that, before adjusting other influencing factors and in terms of smoking status, the current smoking group (OR=1.81, 95% CI 1.27 to 2.58, P<0.01) and the quit smoking group (OR=2.09, 95% CI 1.12 to 3.90, P<0.05) were positively correlated with serum Lp-PLA2 levels compared with the never-smoking group, while the passive smoking group had no correlation with serum Lp-PLA2 levels (OR=1.27, 95% CI 0.59 to 2.73, P>0.05). In terms of daily smoking amount, the 10 to 20 cigarettes group (OR=2.09, 95% CI 1.40 to 3.12, P<0.001) and the 21 to 30 cigarettes group (OR=1.98, 95% CI 1.22 to 3.20, P<0.01) were positively correlated with serum Lp-PLA2 levels compared with the never-smoking group, while the <10 cigarettes group (OR=1.45, 95% CI 0.81 to 2.60, P>0.05) and the >30 cigarettes group (OR=1.17, 95% CI 0.60 to 2.28, P>0.05) had no correlation with serum Lp-PLA2 levels. In terms of smoking years, the 5 to 10 years group (OR=1.94, 95% CI 1.07 to 3.53, P<0.05), the 11 to 20 years group (OR=2.06, 95% CI 1.33 to 3.18, P<0.01), and the >20 years group (OR=1.66, 95% CI 1.11 to 2.47, P<0.05) were positively correlated with serum Lp-PLA2 levels compared with the never-smoking group, while the <5 years group had no correlation with serum Lp-PLA2 levels (OR=1.12, 95% CI 0.38 to 3.33, P>0.05). After adjusting for age and other indicators, the correlation between smoking years and serum Lp-PLA2 levels was the same as before adjustment among the above smoking groups, except that the correlation between the smoking 5 to 10 years group and serum Lp-PLA2 levels was not significant (OR=1.77, 95% CI 0.95 to 3.29, P>0.05).@*CONCLUSIONS@#Smoking is correlated with serum Lp-PLA2 levels in overweight and obese men.

Antileishmanial effects of γCdcPLI, a phospholipase A2 inhibitor from Crotalus durissus collilineatus snake serum, on Leishmania (Leishmania) amazonensis

BACKGROUND Leishmaniasis, a neglected disease caused by the parasite Leishmania, is treated with drugs associated with high toxicity and limited efficacy, in addition to constant reports of the emergence of resistant parasites. In this context, snake serums emerge as good candidates since they are natural sources with the potential to yield novel drugs. OBJECTIVES We aimed to show the antileishmanial effects of γCdcPLI, a phospholipase A2 inhibitor from Crotalus durissus collilineatus snake serum, against Leishmania (Leishmania) amazonensis. METHODS Promastigotes forms were exposed to γCdcPLI, and we assessed the parasite viability and cell cycle, as well as invasion and proliferation assays. FINDINGS Despite the low cytotoxicity effect on macrophages, our data indicate that γCdcPLI has a direct effect on parasites promoting an arrest in the G1 phase and reduction in the G2/M phase at the highest dose tested. Moreover, this PLA2 inhibitor reduced the parasite infectivity when promastigotes were pre-treated. Also, we demonstrated that the γCdcPLI treatment modulated the host cell environment impairing early and late steps of the parasitism. MAIN CONCLUSIONS γCdcPLI is an interesting tool for the discovery of new essential targets on the parasite, as well as an alternative compound to improve the effectiveness of the leishmaniasis treatment.

Clinicopathological characteristics of idiopathic membranous nephropathy in elderly patients / 中华老年医学杂志

Objective:To compare the clinicopathological differences between elderly and non-elderly patients with idiopathic membranous nephropathy(IMN).Methods:Patients diagnosed with IMN via renal biopsy at Beijing Huairou Hospital, Beijing Changping Hospital of Traditional Chinese Medicine, and Beijing Hospital of Traditional Chinese Medicine from January 2017 to August 2021 were retrospectively enrolled.They were classified into the elderly group(≥65 years)and the non-elderly group(<65 years), and the clinicopathological differences between the two groups were compared.Results:A total of 207 IMN patients were included in the study, with a male to female ratio of 1.7∶1.0.There were 56 patients in the elderly group, aged(68.2±3.1)years, and 151 patients in the non-elderly group, aged(48.2±6.2)years.Compared with the non-elderly group, the elderly group had a longer time from onset to renal biopsy and a higher proportion of patients with renal insufficiency and hypertension( P<0.05). The elderly group had a lower eGFR, lower serum albumin, higher serum cholesterol, and higher low-density lipoprotein than the non-elderly group( P<0.05). The proportions of patients with glomerulosclerosis, renal tubular atrophy, and interstitial fibrosis in the elderly group were higher than in the non-elderly group( P<0.05). The positive rates of glomerular PLA2R antigen staining in the two groups were 90.6%(29/32)and 91.0%(111/122), respectively, and there was no statistically significant difference between the two groups.IgG4 deposition represented the most common IgG subtype, with 93.8%(30/32)in the elderly group and 94.3%(115/122)in the non-elderly group.There was no statistical significance between the two groups( P>0.05). Conclusions:Compared with non-elderly IMN patients, a higher proportion of elderly IMN patients has renal insufficiency, hypertension and chronic renal pathology.The glomerular deposition of pathogenic antigens in elderly IMN patients was similar to that in non-elderly IMN patients, suggesting no difference in pathogenesis between the two groups.The clinicopathological differences between the two groups may be related to age and complications.

Secretory phospholipase A2 responsiveness and in vitro anti-tumor activity of oxaliplatin-loaded liposomes modified with facial amphiphiles / 中国药科大学学报

@#Modulating drug release from liposomes at tumor sites are important for eliciting therapeutic effects of platinum drugs considering their low permeability through liposomal membranes, here a novel secretory phospholipase A2 (sPLA2) responsive-liposome system was constructed for oxaliplatin (L-OHP).Lipid ingredients dipalmitoyl phosphatidylcholine and distearoyl phosphoethanolamine-PEG2k, together with facial amphiphiles (FAs) including lithocholic acid (LCA) or 3-keto lithocholic acid (kLCA) were used to prepare sPLA2 responsive-liposome (LCA-Lip or kLCA-Lip) by thin-film hydration method.The physicochemical properties, sPLA2-responsive drug release and anti-tumor activity were evaluated in vitro.The results indicated L-OHP loaded liposomes modified with FAs had similar particle sizes of approximately 100 nm and narrow size distributions (PDI < 0.11).Compared with non-FAs-containing liposomes (C-Lip), LCA-Lip or kLCA-Lip has a comparable entrapment efficiency and loading efficiency.LCA-Lip or kLCA-Lip didn't show significant higher drug leakage at the presence of 10% or 50% fetal bovine serum (FBS) in media than that in media without FBS.Treated with secretory phospholipase A2 from Colo205 cells culture conditioned medium (CCM sPLA2) for 24 h, FAs modified liposomes released about 70% of carboxyfluorescein (CF), while C-Lip only released 20% of CF.Compared to L-OHP loaded C-Lip, L-OHP-loaded FAs-included formulations had much greater anti-proliferative activity against sPLA2-secreting Colo205 cells.In summary, our results shows that LCA or kLCA promotes responsiveness of liposomes to tumor-related sPLA2 and points to a new way to develop platium drugs-loaded liposomal delivery systems with better release mechanisms.

The Use of Lipoprotein-Associated Phospholipase A2 in a Chinese Population to Predict Cardiovascular Events / 生物医学与环境科学（英文）

Objective@#To explore associations between lipoprotein-associated phospholipase A2 (Lp-PLA2) and the risk of cardiovascular events in a Chinese population, with a long-term follow-up.@*Methods@#A random sample of 2,031 participants (73.6% males, mean age = 60.4 years) was derived from the Asymptomatic Polyvascular Abnormalities Community study (APAC) from 2010 to 2011. Serum Lp-PLA2 levels were determined by enzyme-linked immunosorbent assay (ELISA). The composite endpoint was a combination of first-ever stroke, myocardial infarction (MI) or all-cause death. Lp-PLA2 associations with outcomes were assessed using Cox models.@*Results@#The median Lp-PLA2 level was 141.0 ng/mL. Over a median follow-up of 9.1 years, we identified 389 events (19.2%), including 137 stroke incidents, 43 MIs, and 244 all-cause deaths. Using multivariate Cox regression, when compared with the lowest Lp-PLA2 quartile, the hazard ratios with 95% confidence intervals for developing composite endpoints, stroke, major adverse cardiovascular events, and all-cause death were 1.77 (1.24-2.54), 1.92 (1.03-3.60), 1.69 (1.003-2.84), and 1.94 (1.18-3.18) in the highest quartile, respectively. Composite endpoints in 145 (28.6%) patients occurred in the highest quartile where Lp-PLA2 (159.0 ng/mL) was much lower than the American Association of Clinical Endocrinologists recommended cut-off point, 200 ng/mL.@*Conclusion@#Higher Lp-PLA2 levels were associated with an increased risk of cardiovascular event/death in a middle-aged Chinese population. The Lp-PLA2 cut-off point may be lower in the Chinese population when predicting cardiovascular events.

Compositional and toxicological investigation of pooled venom from farm-raised Naja atra

Background: Naja atra is a venomous snake species medically relevant in China. In the current study, we evaluated the composition and toxicological profile of venom collected from farm-raised N. atra. Methods: Venom was collected from third-generation captive bred N. atra on a snake farm in Hunan Province, China. The venom was analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis and nano-liquid chromatography with electrospray ionization tandem mass spectrometry. In addition, hemolytic activity, median lethal dose, serum biochemical and histopathological parameters were accessed. Results: N. atra venom proteome was dominated by phospholipase A2 (46.5%) and three-finger toxins (41.4 %), and a set of common low relative abundance proteins, including cysteine-rich secretory proteins (4.7%), NGF-beta (2.4%), snake venom metalloproteinase (1.5%), glutathione peroxidase (0.6%), vespryn (0.3%), and 5ʹ-nucleotidases (0.2%) were also found. Furthermore, the venom exhibited direct hemolytic activity, neurotoxicity, myotoxicity, and high lethal potency in mice, with a subcutaneous median lethal dose of 1.02 mg/kg. Histopathological analysis and serum biochemical tests revealed that venom caused acute hepatic, pulmonary and renal injury in mice. Conclusion: This study revealed the composition and toxicity of venom collected from farm-raised N. atra, thereby providing a reference for the analysis of venom samples collected from captive-born venomous snakes in the future.(AU)