RESUMO
BACKGROUND: Mosquitoes pose a risk to human health worldwide, and correct species identification and detection of cryptic species are the most important keys for surveillance and control of mosquito vectors. In addition to traditional identification based on morphology, DNA barcoding has recently been widely used as a complementary tool for reliable identification of mosquito species. The main objective of this study was to create a reference DNA barcode library for the Croatian mosquito fauna, which should contribute to more accurate and faster identification of species, including cryptic species, and recognition of relevant vector species. METHODS: Sampling was carried out in three biogeographical regions of Croatia over six years (2017-2022). The mosquitoes were morphologically identified; molecular identification was based on the standard barcoding region of the mitochondrial COI gene and the nuclear ITS2 region, the latter to identify species within the Anopheles maculipennis complex. The BIN-RESL algorithm assigned the COI sequences to the corresponding BINs (Barcode Index Number clusters) in BOLD, i.e. to putative MOTUs (Molecular Operational Taxonomic Units). The bPTP and ASAP species delimitation methods were applied to the genus datasets in order to verify/confirm the assignment of specimens to specific MOTUs. RESULTS: A total of 405 mosquito specimens belonging to six genera and 30 morphospecies were collected and processed. Species delimitation methods assigned the samples to 31 (BIN-RESL), 30 (bPTP) and 28 (ASAP) MOTUs, with most delimited MOTUs matching the morphological identification. Some species of the genera Culex, Aedes and Anopheles were assigned to the same MOTUs, especially species that are difficult to distinguish morphologically and/or represent species complexes. In total, COI barcode sequences for 34 mosquito species and ITS2 sequences for three species of the genus Anopheles were added to the mosquito sequence database for Croatia, including one individual from the Intrudens Group, which represents a new record for the Croatian mosquito fauna. CONCLUSION: We present the results of the first comprehensive study combining morphological and molecular identification of most mosquito species present in Croatia, including several invasive and vector species. With the exception of some closely related species, this study confirmed that DNA barcoding based on COI provides a reliable basis for the identification of mosquito species in Croatia.
Assuntos
Culicidae , Código de Barras de DNA Taxonômico , Culicidae/anatomia & histologia , Culicidae/classificação , Culicidae/genética , Mosquitos Vetores/anatomia & histologia , Mosquitos Vetores/classificação , Mosquitos Vetores/genética , Código de Barras de DNA Taxonômico/métodos , Ciclo-Oxigenase 1/genética , DNA Espaçador Ribossômico/genética , FilogeniaRESUMO
Platelet endothelial aggregation receptor 1 (PEAR1) and prostaglandin endoperoxide synthase 1 (PTGS1) polymorphisms can affect laboratory aspirin resistance. However, the impact of genetic polymorphisms on the recurrence of ischemic stroke (IS) patients treated with aspirin is not fully understood. This study aimed to examine the relationship between gene polymorphisms of PEAR1 and PTGS1 and IS recurrence in patients treated with aspirin. Peripheral blood samples were collected from 174 patients with nonrecurrent IS and 34 with recurrent IS after aspirin treatment. Follow-up was performed on all patients. PEAR1 rs12041331 and PTGS1 rs10306114 polymorphisms were determined using the PCR fluorescence probe method. And the correlations of them with the clinical characteristics were examined by multivariable logistic regression analysis. The distribution frequencies of PEAR1 rs12041331 and PTGS1 rs10306114 genotypes were in Hardy-Weinberg equilibrium, and there was no significant difference in the distribution of PEAR1 rs12041331 polymorphism. Compared to the nonrecurrent group, the AA genotype of the PTGS1 polymorphism was more frequent in the recurrent group (59.77% vs 35.29%, Pâ =â .003), and the A allele also showed a higher frequency than the G allele in the recurrent group (Pâ =â .001). Multivariable logistic regression analysis showed that smoking (ORâ =â 5.228, 95% CI: 1.938-14.102, Pâ =â .001), coronary heart disease (ORâ =â 4.754, 95% CI: 1.498-15.089, Pâ =â .008), and the polymorphism at PTGS1(A>G) AA/AGâ +â GG (ORâ =â 2.955, 95% CI: 1.320-6.616, Pâ =â .008) were independently associated with IS recurrence in Chinese patients. Our findings suggested that PTGS rs10306114 polymorphisms should receive more attention in the use of aspirin in patients with IS.
Assuntos
Aspirina , Ciclo-Oxigenase 1 , AVC Isquêmico , Inibidores da Agregação Plaquetária , Polimorfismo de Nucleotídeo Único , Recidiva , Humanos , Masculino , Feminino , Aspirina/uso terapêutico , Ciclo-Oxigenase 1/genética , China/epidemiologia , Pessoa de Meia-Idade , AVC Isquêmico/genética , AVC Isquêmico/tratamento farmacológico , Idoso , Seguimentos , Inibidores da Agregação Plaquetária/uso terapêutico , Receptores de Superfície Celular/genética , Povo Asiático/genética , GenótipoRESUMO
Piroplasmids and Hepatozoon spp. Are apicomplexan protozoa that may cause disease in several canid species. The present study aimed to expand the knowledge on the diversity of piroplasmids and Hepatozoon in crab-eating foxes (Cerdocyon thous; n = 12) sampled in the Pantanal of Mato Grosso do Sul State, central-western Brazil. PCR assays based on the 18S rRNA were used as screening. Three (25%) and 11 (91.7%) were positive for piroplasmids and Hepatozoon spp., respectively. Co-infection was found in three C. thous. Phylogenetic analyses based on the near-complete 18S rRNA, cox-1 and hsp70 genes evidenced the occurrence of a novel of Babesia spp. (namely Babesia pantanalensis nov. sp.) closely related to Rangelia vitalii and Babesia sp. 'Coco'. This finding was supported by the genetic divergence analysis which showed (i) high divergence, ranging from 4.17 to 5.62% for 18 S rRNA, 6.16% for hps70 and 4.91-9.25% for cox-1 and (ii) the genotype network (which displayed sequences separated from the previously described Piroplasmida species by median vectors and several mutational events). Also, phylogenetic analysis based on the 18S rRNA gene of Hepatozoon spp. positioned the sequences obtained herein in a clade phylogenetically related to Hepatozoon sp. 'Curupira 2', Hepatozoon sp. detected in domestic and wild canids from Uruguay and Hepatozoon americanum. The present study described Babesia pantanalensis nov sp. and Hepatozoon closely related to H. americanum in crab-eating foxes from Brazil. Moreover, the coinfection by piroplasmids and Hepatozoon sp. for the first time in crab-eating foxes strongly suggesting that this wild canid species potentially acts as a bio-accumulate of hemoprotozoan in wild environment.
Assuntos
Babesia , Babesiose , Coccidiose , DNA de Protozoário , Genótipo , Filogenia , RNA Ribossômico 18S , Animais , Babesia/genética , Babesia/classificação , Babesia/isolamento & purificação , RNA Ribossômico 18S/genética , Babesiose/parasitologia , Babesiose/epidemiologia , Brasil/epidemiologia , Coccidiose/veterinária , Coccidiose/parasitologia , Coccidiose/epidemiologia , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Eucoccidiida/genética , Eucoccidiida/classificação , Eucoccidiida/isolamento & purificação , Ciclo-Oxigenase 1/genética , Reação em Cadeia da Polimerase/veterinária , Proteínas de Choque Térmico HSP70/genética , Coinfecção/veterinária , Coinfecção/parasitologia , Raposas/parasitologia , Canidae/parasitologia , Complexo IV da Cadeia de Transporte de Elétrons/genéticaRESUMO
Exposure to nicotine by cigarette smoking have shown strongly defectives on the physiological function of ovaries, which in turn leads to disorders of fertility in women. However, the potential molecular mechanisms remain to be elucidated. In this study, we notably found that nicotine was likely to specifically raise the expression of histone deacetylase 3 (HDAC3) to promote the apoptosis and autophagy of granulosa cells (GCs) and block follicular maturation. Moreover, prostaglandin E2 (PGE2) inhibited the apoptosis of GCs and facilitated follicular maturation, and nicotine appeared to inhibit PGE2 secretion by freezing the expression of cyclooxygenase 1 (COX1), which was the rate-limiting and essential enzyme for PGE2 synthesis. Epigenetically, the nicotine was observed to diminish the histone H3 lysine 9 acetylation (H3K9ac) level and compact the chromatin accessibility in -1776/-1499â¯bp region of COX1 by evoking the expression of HDAC3, with the deactivated Cas9-HDAC3/sgRNA system. Mechanistically, the COX1 protein was found to pick up and degrade the autophagy related protein beclin 1 (BECN1) to control the autophagy of GCs. These results provided a potential new molecular therapy to recover the damage of female fertility induced by nicotine from cigarette smoking.
Assuntos
Autofagia , Dinoprostona , Células da Granulosa , Nicotina , Feminino , Autofagia/efeitos dos fármacos , Animais , Nicotina/toxicidade , Células da Granulosa/efeitos dos fármacos , Dinoprostona/metabolismo , Camundongos , Histona Desacetilases/metabolismo , Folículo Ovariano/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 1/genéticaRESUMO
BACKGROUND: Low-dose aspirin is widely used for the secondary prevention of cardiovascular disease. The beneficial effects of low-dose aspirin are attributable to its inhibition of platelet Cox (cyclooxygenase)-1-derived thromboxane A2. Until recently, the use of the Pf4 (platelet factor 4) Cre has been the only genetic approach to generating megakaryocyte/platelet ablation of Cox-1 in mice. However, Pf4-ΔCre displays ectopic expression outside the megakaryocyte/platelet lineage, especially during inflammation. The use of the Gp1ba (glycoprotein 1bα) Cre promises a more specific, targeted approach. METHODS: To evaluate the role of Cox-1 in platelets, we crossed Pf4-ΔCre or Gp1ba-ΔCre mice with Cox-1flox/flox mice to generate platelet Cox-1-/- mice on normolipidemic and hyperlipidemic (Ldlr-/-; low-density lipoprotein receptor) backgrounds. RESULTS: Ex vivo platelet aggregation induced by arachidonic acid or adenosine diphosphate in platelet-rich plasma was inhibited to a similar extent in Pf4-ΔCre Cox-1-/-/Ldlr-/- and Gp1ba-ΔCre Cox-1-/-/Ldlr-/- mice. In a mouse model of tail injury, Pf4-ΔCre-mediated and Gp1ba-ΔCre-mediated deletions of Cox-1 were similarly efficient in suppressing platelet prostanoid biosynthesis. Experimental thrombogenesis and attendant blood loss were similar in both models. However, the impact on atherogenesis was divergent, being accelerated in the Pf4-ΔCre mice while restrained in the Gp1ba-ΔCres. In the former, accelerated atherogenesis was associated with greater suppression of PGI2 biosynthesis, a reduction in the lipopolysaccharide-evoked capacity to produce PGE2 (prostaglandin E) and PGD2 (prostanglandin D), activation of the inflammasome, elevated plasma levels of IL-1ß (interleukin), reduced plasma levels of HDL-C (high-density lipoprotein receptor-cholesterol), and a reduction in the capacity for reverse cholesterol transport. By contrast, in the latter, plasma HDL-C and α-tocopherol were elevated, and MIP-1α (macrophage inflammatory protein-1α) and MCP-1 (monocyte chemoattractant protein 1) were reduced. CONCLUSIONS: Both approaches to Cox-1 deletion similarly restrain thrombogenesis, but a differential impact on Cox-1-dependent prostanoid formation by the vasculature may contribute to an inflammatory phenotype and accelerated atherogenesis in Pf4-ΔCre mice.
Assuntos
Plaquetas , Ciclo-Oxigenase 1 , Modelos Animais de Doenças , Integrases , Camundongos Endogâmicos C57BL , Camundongos Knockout , Agregação Plaquetária , Fator Plaquetário 4 , Receptores de LDL , Animais , Plaquetas/metabolismo , Plaquetas/efeitos dos fármacos , Plaquetas/enzimologia , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/deficiência , Agregação Plaquetária/efeitos dos fármacos , Fator Plaquetário 4/genética , Fator Plaquetário 4/metabolismo , Integrases/genética , Receptores de LDL/genética , Receptores de LDL/deficiência , Masculino , Camundongos , Aterosclerose/genética , Aterosclerose/patologia , Aterosclerose/enzimologia , Aterosclerose/prevenção & controle , Aterosclerose/sangue , Hiperlipidemias/sangue , Hiperlipidemias/genética , Hiperlipidemias/enzimologia , Fenótipo , Proteínas de Membrana , Complexo Glicoproteico GPIb-IX de PlaquetasRESUMO
PURPOSE: Strongyloides stercoralis is a parasite with special characteristics presenting it as a unique nematode. Iran is an endemic area for S. stercoralis. In this study, nested-qPCR-high resolution melting (HRM) technology was applied on some human isolates of S. stercoralis from this country by focusing on evolutionary genetics analysis. METHODS: Twelve human isolates of S. stercoralis were collected from four endemic provinces of Iran. Genomic DNA was extracted from a single filariform larva for every isolate. Using specific primers targeting partial regions in cox1 gene, nested-qPCR-HRM was performed and melting-curve profiles were analyzed alongside the evaluation of genetic proximity and phylogenetic analysis using MEGA7 and DnaSP5 software. RESULTS: The melting temperature (Tm) values of the isolates were 77.9 °C-78.3 °C. All isolates from Guilan, Mazandaran, and Khouzestan Provinces shared Tm values of 78.2 °C to 78.3 °C, while the isolates from Hormozgan Province showed Tm values of 77.9 °C, 78.0 °C, and 78.1 °C. The phylogenetic tree illustrated that the sequences of the current study included nine haplotypes. Tajima's D index analyses showed that cox1 gene in S. stercoralis isolates was negative (Tajima's D = - 0.27). CONCLUSION: The isolates were divided into five temperature groups. Although HRM assay compared to PCR sequencing identified more limited genetic changes, it revealed that the mean of Tm of the isolates from Hormozgan Province was lower than those of other provinces and represented specific haplotypes for this geographical region on the phylogenetic tree.
Assuntos
Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Strongyloides stercoralis , Estrongiloidíase , Animais , Irã (Geográfico)/epidemiologia , Strongyloides stercoralis/genética , Strongyloides stercoralis/isolamento & purificação , Strongyloides stercoralis/classificação , Humanos , Estrongiloidíase/parasitologia , Estrongiloidíase/epidemiologia , DNA de Helmintos/genética , Temperatura de Transição , Haplótipos , Ciclo-Oxigenase 1/genéticaRESUMO
Resveratrol (Res) has been demonstrated to have beneficial effects on gouty nephropathy (GN). However, the mechanisms of Res on GN remain unclear. This study aimed to investigate the mechanisms of Res on GN. In this study, network pharmacology technology was used to predict the Res targets in the prevention and treatment of GN. Renal metabonomics was used to identify differential metabolites in kidney tissue of GN model rats. Finally, molecular docking technology was used to verify the binding ability of Res to key targets. Metabonomics analysis showed that 24 potentially important metabolites were involved in the prevention and treatment of GN with Res. After exposure to Res, metabolite levels normalized. The network pharmacology analysis showed that 24 key targets were involved in the prevention and treatment of GN disease. According to the metabolite-gene network diagram, we identified two core genes, PTGS1 and PTGS2, and found that both were involved in the arachidonic acid metabolism pathway. Molecular docking further verified the affinity of Res binding to PTGS1 and PTGS2. In conclusion, the mechanism of Res against GN may be the regulation of arachidonic acid metabolism through the regulation of PTGS 1 and PTGS 2.
Assuntos
Rim , Proteínas de Membrana , Metabolômica , Simulação de Acoplamento Molecular , Farmacologia em Rede , Ratos Sprague-Dawley , Resveratrol , Animais , Resveratrol/farmacologia , Resveratrol/química , Rim/efeitos dos fármacos , Rim/metabolismo , Ratos , Metabolômica/métodos , Masculino , Ciclo-Oxigenase 2/metabolismo , Ciclo-Oxigenase 2/genética , Metaboloma/efeitos dos fármacos , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/química , Gota/metabolismo , Gota/tratamento farmacológico , Nefropatias/metabolismo , Nefropatias/tratamento farmacológicoRESUMO
OBJECTIVE: To investigate the sequences of internal transcribed spacer 2 (ITS2) and cyclooxygenase 1 (COX1) genes of Paragonimus metacercariae in freshwater crabs in Henan Province, identify the species of Paragonimus and evaluate its genetic relationships with Paragonimus isolates from other provinces in China. METHODS: Freshwater crabs were collected from 8 survey sites in Zhengzhou, Luoyang, Pingdingshan, Nanyang and Jiyuan cities of Henan Province from 2016 to 2021, and Paragonimus metacercariae were detected in freshwater crabs. Genomic DNA was extracted from Paragonimus metacercariae, and the ITS2 and COX1 genes were amplified using PCR assay, followed by sequencing of PCR amplification products. The gene sequences were spliced and aligned using the software DNASTAR, and aligned with the sequences of Paragonimus genes in the GenBank. Phylogenetic trees were created using the MEGA6 software with the Neighbor-Joining method based on ITS2 and COX1 gene sequences, with Fasciola hepatica as the outgroup. RESULTS: The detection rates of Paragonimus metacercariae were 6.83% (11/161), 50.82% (31/61), 18.52% (5/26), 8.76% (12/137), 14.29% (9/63), 17.76% (19/105), 18.50% (32/173) and 42.71% (41/96) in freshwater crabs from 8 survey sites in Zhengzhou, Luoyang, Pingdingshan, Nanyang and Jiyuan cities of Henan Province, with a mean detection rate of 19.46% (160/822), and a mean infection intensity of 0.57 metacercariae/g. The amplified ITS2 and COX1 gene fragments of Paragonimus were approximately 500 bp and 450 bp in lengths, respectively. The ITS2 gene sequences of Paragonimus metacercariae from 8 survey sites of Henan Province showed the highest homology (99.8% to 100.0%) with the gene sequence of P. skrjabini (GenBank accession number: MW960209.1), and phylogenetic analysis showed that the Paragonimus in this study was clustered into the same clade with P. skrjabini from Sichuan Province (GenBank accession number: AY618747.1), Guangxi Zhuang Autonomous Region (GenBank accession number: AY618729.1) and Hubei Province (GenBank accession number: AY618751.1), and P. miyazaki from Fujian Province (GenBank accession number: AY618741.1) and Japan (GenBank accession number: AB713405.1). The COX1 gene sequences of Paragonimus metacercariae from 8 survey sites of Henan Province showed the highest homology (90.0% to 100.0%) with the gene sequence of P. skrjabini (GenBank accession number: AY618798.1), and phylogenetic analysis showed that the Paragonimus in this study was clustered into the same clade with all P. skrjabini and clustered into the same sub-clade with P. skrjabini from Hubei Province (GenBank accession numbers: AY618782.1 and AY618764.1). CONCLUSIONS: Paragonimus species from freshwater crabs in Henan Province were all characterized as P. skrjabini, and the ITS2 and COX1 gene sequences had the highest homology to those of P. skrjabini from Hubei Province. The results provide insights into study of Paragonimus in Henan Province and China.
Assuntos
Braquiúros , Paragonimíase , Paragonimus , Animais , Paragonimus/genética , Braquiúros/genética , Ciclo-Oxigenase 1/genética , Filogenia , China/epidemiologia , Análise de Sequência de DNARESUMO
The mandible condylar process cartilage (CP) of Wistar rats is a secondary cartilage and acts as a mandibular growth site. This phenomenon depends on adequate proteins intake and hormone actions, including insulin. Objectives The present study evaluated the morphological aspects and the expression of the insulin receptor (IR) in the cartilage of the condylar process (CP) of rats subjected to protein undernourishment. Material and Methods The nourished group received a 20% casein diet, while the undernourished group (U) received a 5% casein diet. The re-nourished groups, R and RR, were used to assess the effects of re-nutrition during puberty and adulthood, respectively. CPs were processed and stained with picro-sirius red, safranin-O and azocarmine. Scanning electron microscopy and immunohistochemistry were also performed. Results The area of the CP cartilage and the number of cells in the chondroblastic layer decreased in the U group, as did the thickness of the CP layer in the joint and hypertrophic layer. Renourishment during the pubertal stage, but not during the adult phase, restored these parameters. The cell number was restored when re-nutrition occurred in the pubertal stage, but not in the adult phase. The extracellular matrix also decreased in the U group, but was restored by re-nutrition during the pubertal stage and further increased in the adult phase. IR expression was observed in all CPs, being higher in the chondroblastic and hypertrophic cartilage layers. The lowest expression was found in the U and RR groups. Conclusions Protein malnutrition altered the cellularity, the area, and the fibrous cartilage complex, as well as the expression of the IRs. .
Assuntos
Animais , Camundongos , Anti-Inflamatórios não Esteroides/metabolismo , Ciclo-Oxigenase 1/metabolismo , /metabolismo , Inibidores de Ciclo-Oxigenase/metabolismo , Piroxicam/análogos & derivados , Tiazinas/metabolismo , Tiazóis/metabolismo , Substituição de Aminoácidos , Anti-Inflamatórios não Esteroides/química , Arginina/química , Arginina/genética , Arginina/metabolismo , Sítios de Ligação , Domínio Catalítico , Ciclo-Oxigenase 1/química , Ciclo-Oxigenase 1/genética , /química , /genética , Inibidores de Ciclo-Oxigenase/química , Ligação de Hidrogênio , Leucina/química , Leucina/genética , Leucina/metabolismo , Mutação , Piroxicam/química , Piroxicam/metabolismo , Estrutura Secundária de Proteína , Serina/química , Serina/genética , Serina/metabolismo , Tiazinas/química , Tiazóis/química , Tirosina/química , Tirosina/genética , Tirosina/metabolismo , ÁguaRESUMO
OBJECTIVE: Identify the influence of ovarian hormone deprivation in expression genes on the lower urinary tract of rats. MATERIALS AND METHODS: This study deals with gene screening on lower urinary tract of rats. Fifty isogenic rats divided in two groups of twenty-five animals have their lower urinary tract surgically removed: group I, ovariectomized rats 30 days prior to surgery; group II, non-ovariectomized rats. Total RNA was isolated from bladder and urethra, and differential expression of genes was analyzed quantitative, qualitative and comparatively by array technology and RT-PCR. RESULTS: A total of 76 candidate genes were identified as differentially expressed between the groups, 26 being lower expressed in group II, and 50 in group I. Among them, differential expression validation was confirmed by RT-PCR for three lower expressed genes in group I: Vascular Endothelial Growth Factor (VEGF), Beta-2 Microglobulin (B2M) and Cytochrome c Oxidase subunit I (COX I). CONCLUSION: Ovarian hormone deprivation influences the expression genes on lower urinary tract. We demonstrated that a 30-day period of castration down regulate the expression of VEGF, B2M and COX I in adult rats which are involved in activities of angiogenesis, immune responses and cellular metabolism respectively.
Assuntos
Animais , Feminino , Ratos , Estrogênios/deficiência , Expressão Gênica , Sistema Urinário/metabolismo , Doenças Urológicas/genética , Fator A de Crescimento do Endotélio Vascular/genética , Ciclo-Oxigenase 1/genética , Modelos Animais de Doenças , Estrogênios/farmacologia , Perfilação da Expressão Gênica , Hibridização In Situ , Proteínas de Membrana/genética , Análise de Sequência com Séries de Oligonucleotídeos , Ovariectomia , Ovário/fisiologia , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sistema Urinário/efeitos dos fármacos , Doenças Urológicas/metabolismo , Fator A de Crescimento do Endotélio Vascular/sangue , /genéticaRESUMO
Hypoxia activates endothelial cells by the action of reactive oxygen species generated in part by cyclooxygenases (COX) production enhancing leukocyte transmigration. We investigated the effect of specific COX inhibition on the function of endothelial cells exposed to hypoxia. Mouse immortalized endothelial cells were subjected to 30 min of oxygen deprivation by gas exchange. Acridine orange/ethidium bromide dyes and lactate dehydrogenase activity were used to monitor cell viability. The mRNA of COX-1 and -2 was amplified and semi-quantified before and after hypoxia in cells treated or not with indomethacin, a non-selective COX inhibitor. Expression of RANTES (regulated upon activation, normal T cell expressed and secreted) protein and the protective role of heme oxygenase-1 (HO-1) were also investigated by PCR. Gas exchange decreased partial oxygen pressure (PaO2) by 45.12 ± 5.85 percent (from 162 ± 10 to 73 ± 7.4 mmHg). Thirty minutes of hypoxia decreased cell viability and enhanced lactate dehydrogenase levels compared to control (73.1 ± 2.7 vs 91.2 ± 0.9 percent, P < 0.02; 35.96 ± 11.64 vs 22.19 ± 9.65 percent, P = 0.002, respectively). COX-2 and HO-1 mRNA were up-regulated after hypoxia. Indomethacin (300 æM) decreased COX-2, HO-1, hypoxia-inducible factor-1alpha and RANTES mRNA and increased cell viability after hypoxia. We conclude that blockade of COX up-regulation can ameliorate endothelial injury, resulting in reduced production of chemokines.