The oxidative process of LDL particles generates molecules which are structurally similar to platelet-activating factor (PAF), and some effects of oxidized LDL (oxLDL) have been shown to be dependent ...on PAF receptor (PAFR) activation. In a previous study, we showed that PAFR is required for upregulation of CD36 and oxLDL uptake. In the present study we analyzed the molecular mechanisms activated by oxLDL in human macrophages and the contribution of PAFR to this response. Human adherent monocytes/macrophages were stimulated with oxLDL. Uptake of oxLDL and CD36 expression were determined by flow cytometry; MAP kinases and Akt phosphorylation by Western blot; IL-8 and MCP-1 concentration by ELISA and mRNA expression by real-time PCR. To investigate the participation of the PI3K/Akt pathway, Gαi-coupled protein or PAFR, macrophages were treated with LY294002, pertussis toxin or with the PAFR antagonists WEB2170 and CV3988, respectively before addition of oxLDL. It was found that the addition of oxLDL to human monocytes/macrophages activates the PI3K/Akt pathway which in turn activates the MAPK (p38 and JNK). Phosphorylation of Akt requires the engagement of PAFR and a Gαi-coupled protein. The upregulation of CD36 protein and the uptake of oxLDL as well as the IL-8 production are dependent on PI3K/Akt pathway activation. The increased CD36 protein expression is dependent on PAFR and Gαi-coupled protein. Transfection studies using HEK 293t cells showed that oxLDL uptake occurs with either PAFR or CD36, but IL-8 production requires the co-transfection of both PAFR and CD36. These findings show that PAFR has a pivotal role in macrophages response to oxLDL and suggest that pharmacological intervention at the level of PAFR activation might be beneficial in atherosclerosis.
Platelet-activating factor (PAF) is a lipid mediator with important pro-inflammatory effects, being synthesized by several cell types including kidney cells. Although there is evidence of its ...involvement in acute renal dysfunction, its role in progressive kidney injury is not completely known. In the present study, we investigated the role of PAF receptor (PAFR) in an experimental model of chronic renal disease. Wild-type (WT) and PAFR knockout (KO) mice underwent unilateral ureter obstruction (UUO), and at kill time, urine and kidney tissue was collected. PAFR KO animals compared with WT mice present: (a) less renal dysfunction, evaluated by urine protein/creatinine ratio; (b) less fibrosis evaluated by collagen deposition, type I collagen, Lysyl Oxidase-1 (LOX-1) and transforming growth factor β (TGF-β) gene expression, and higher expression of bone morphogenetic protein 7 (BMP-7) (3.3-fold lower TGF-β/BMP-7 ratio); (c) downregulation of extracellular matrix (ECM) and adhesion molecule-related machinery genes; and (d) lower levels of pro-inflammatory cytokines. These indicate that PAFR engagement by PAF or PAF-like molecules generated during UUO potentiates renal dysfunction and fibrosis and might promote epithelial-to-mesenchymal transition (EMT). Also, early blockade of PAFR after UUO leads to a protective effect, with less fibrosis deposition. In conclusion, PAFR signaling contributes to a pro-inflammatory environment in the model of obstructive nephropathy, favoring the fibrotic process, which lately will generate renal dysfunction and progressive organ failure.
Neodymium based fluorescence presents several advantages in comparison to conventional rare earth or enzyme-substrate based fluorescence emitting sources (e.g.Tb, HRP) . Based on this fact we have ...herein explored a Nd-based fluoroimmunoassay. We efficiently detected the presence of an oxidized low-density lipoprotein (oxLDL) in human plasma a well-known marker for cardiovascular diseases, which causes around 30% of deaths worldwide. Conventional fluoroimmunoassay uses time-resolved luminescence techniques, with detection in the visible range, to eliminate the fluorescence background from the biological specimens. By using an immunoassay based on functionalized Y sub(2O) sub(3):Ndsuper3+ nanoparticles, where the excitation and emission processes in the Ndsuper3+ ion occur in the near-infrared (NIR) region, we have succeeded in eliminating the interferences from the biological fluorescence background, avoiding the use of time-resolved techniques. This yields higher emission intensity from the Ndsuper3+-nanolabels and efficient detection of anti-oxidized low-density lipoproteins (anti-oxLDL) by Y sub(2O) sub(3):Ndsuper3+-antibody-antigen conjugation, leading to a novel biolabeling method.
Macrophage interaction with oxidized low-density lipoprotein (oxLDL) leads to its differentiation into foam cells and cytokine production, contributing to atherosclerosis development. In a previous ...study, we showed that CD36 and the receptor for platelet-activating factor (PAFR) are required for oxLDL to activate gene transcription for cytokines and CD36. Here, we investigated the localization and physical interaction of CD36 and PAFR in macrophages stimulated with oxLDL. We found that blocking CD36 or PAFR decreases oxLDL uptake and IL-10 production. OxLDL induces IL-10 mRNA expression only in HEK293T expressing both receptors (PAFR and CD36). OxLDL does not induce IL-12 production. The lipid rafts disruption by treatment with beta CD reduces the oxLDL uptake and IL-10 production. OxLDL induces co-immunoprecipitation of PAFR and CD36 with the constitutive raft protein flotillin-1, and colocalization with the lipid raft-marker GM1-ganglioside. Finally, we found colocalization of PAFR and CD36 in macrophages from human atherosclerotic plaques. Our results show that oxLDL induces the recruitment of PAFR and CD36 into the same lipid rafts, which is important for oxLDL uptake and IL-10 production. This study provided new insights into how oxLDL interact with macrophages and contributing to atherosclerosis development.
Amazonia constitutes one of the most ethnically diverse regions in the world. However, our understanding of the arrival and historical trajectories of people in Amazonia is still poorly understood. ...Our recent excavations in the Serranía de la Lindosa have begun to fill this gap and provide new insights into the first human societies that settled in the Colombian Amazon region during the Younger Dryas (YD) period of the late Pleistocene. This paper details the stratigraphy, taphonomy and chronological framework of two rock shelters, Cerro Montoya 1 and Limoncillos, from excavations carried out by the LASTOURNEY project between 2021 and 2022. Based on radiocarbon dates from five multicomponent sites (Cerro Azul, Cerro Montoya 1, Limoncillos, Angosturas II and Casita de Piedra), four distinct phases of occupation are modelled using OxCal program (v.4.4). late Pleistocene-early Holocene (12.6–10.0 cal ka BP); early to middle Holocene (9.5–5.9 cal ka BP); initial late Holocene (4.1–3.7 cal ka BP), and late Holocene (3.0–0.3 cal ka BP). We establish the arrival date of the first human groups to the Colombia Amazon by ∼12.6 cal ka BP, who settled in a tropical rainforest environment, practised a generalised subsistence, had an expedient unifacial technology, and began to paint with ochre on the walls of the mesa-top tepuis by at least ∼10.2 cal ka BP. The chronology indicates gaps in the sequence during the middle Holocene, between 5.9–4.1 cal ka BP, likely representing periods of abandonment.
•We report several new evidences of early peopling of Amazonia River basin.•We report new evidences of human occupations of the Serranía La Lindosa (Colombian Amazon).•We report the data of two rock shelters, Cerro Montoya 1 and Limoncillos.•We report several lines of evidence on the human adaptability to the Colombian Amazon lowlands.•The humans who settled in the Serrania La Lindosa “humanized” the territory by rock art.
•Exploration of animal representation in the rock art and zooarchaeological assemblage at Serrania de la Lindosa, in the Colombian Amazon.•Analyses demonstrate extensive knowledge and exploitation of ...a wide array of animal resources across a broad range of habitats.•Painted animal figures range from taxonomically specific to ambiguous and can embed a fluidity between humans and animals.•Ethnographies support complex human-animal relationships for Amazonian ontologies.
The Serranía de la Lindosa in the Colombian Amazon hosts one of the most spectacular global rock art traditions. Painted in vibrant ochre pigments, the artwork depicts abstract and figurative designs – including a high diversity of animal motifs – and holds key information for understanding how Amazonians made sense of their world. We compare a zooarchaeological assemblage with painted depictions of animals at the Cerro Azul site, and utilise relevant ethnographies and ethnohistories. A lack of direct proportional relationships between the animal representation in the art and zooarchaeological remains alludes to the complex socio-cultural interconnection between Amazonian communities and their ritualised environments. We discuss the benefits and limitations of quantitative categorisation and explore Indigenous ontologies, highlighting Amazonian perspectives on human-animal relationships.
In this study, 1,833 systemic sclerosis (SSc) cases and 3,466 controls were genotyped with the Immunochip array. Classical alleles, amino acid residues, and SNPs across the human leukocyte antigen ...(HLA) region were imputed and tested. These analyses resulted in a model composed of six polymorphic amino acid positions and seven SNPs that explained the observed significant associations in the region. In addition, a replication step comprising 4,017 SSc cases and 5,935 controls was carried out for several selected non-HLA variants, reaching a total of 5,850 cases and 9,401 controls of European ancestry. Following this strategy, we identified and validated three SSc risk loci, including DNASE1L3 at 3p14, the SCHIP1-IL12A locus at 3q25, and ATG5 at 6q21, as well as a suggested association of the TREH-DDX6 locus at 11q23. The associations of several previously reported SSc risk loci were validated and further refined, and the observed peak of association in PXK was related to DNASE1L3. Our study has increased the number of known genetic associations with SSc, provided further insight into the pleiotropic effects of shared autoimmune risk factors, and highlighted the power of dense mapping for detecting previously overlooked susceptibility loci.
The copaiba oil is a common natural product used in cosmetic industry and as a nutraceutical product. However, lack of quality control and scarce knowledge about its antimicrobial activity is a point ...of concern. The proposal of this study was to investigate the physicochemical properties and the antimicrobial activity of five commercial brands of copaiba oil.
Acidity and ester index, refractory index, solubility in alcohol, and thin layer chromatography were performed to verify the physicochemical properties of five commercial copaiba oils sold in local pharmacies. Ultra performance liquid chromatography coupled with diode-array detection and electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-DAD/ESI-Q-TOF-MS) was used to investigate diterpene acids while the volatile compounds were analysed by gas chromatography-mass spectrometry (GC-MS). Antibacterial and antifungal activities were also evaluated by agar diffusion technique; and minimal inhibitory concentration and maximal bactericidal concentration were defined for each sample and bacteria.
The physical-chemical analysis revealed heterogeneity between all samples analysed. The A1 sample showed characteristics of copaiba oil and was mainly composed by hydrocarbon sesquiterpenes (29.95% β-bisabolene, 25.65% Z-α-bergamotene and 10.27% β-cariophyllene). Among diterpene acids, the UPLCDAD/ESI-Q-TOF-MS data are compatible with presence of copalic and/or kolavenic acid (m/z 305 M + H+). Candida albicans was sensitive to almost all samples at high concentration and Saccaromyces. Cerevisiae showed sensitivity to A1 sample at 100 mg/mL. Although variable, all samples showed antibacterial activity. Significant activity was seen for A3 (19.0 ±0 and 15.6 ±0.5 mm), A4 (16.6 ±0.5 and 15.6 ±0 mm), and A5 (17.1 ±0 and 17.1 ±0 mm) on Staphylococcus saprophyticus and S. aureus, respectively. All samples were active against Klebsiella pneumoniae showing ≥15 mm diameter halo inhibition; and only A2 was active against Eschirichia coli. Phytopatogens tested revealed resistance of Ralstonia solanacearum CGH12 to all samples and susceptibility of Xcv 112 strain of Xanthomonas campestris pv campestris to almost all samples. MIC and MMC showed bacteriostatic effect against clinical interest bacteria and bactericidal effect against phytopatogens.
The results from physicochemical analysis reinforce the fact that it is imperative to include simple conventional methods in the analysis of oil products. The analysis of copaiba oil gives safe products and purity which ensure products with quality. Also, since copaiba oil is an over-the-counter product the results indicate that pharmacosurveillance must be improved by the governmental regulation agency to avoid microorganism resistance selection and to achieve better international quality products.
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