A Genetic Tool to Identify Predators Responsible for Livestock Attacks in South America and Recommendations for Human-Wildlife Conflict Mitigation.

Livestock predation induces global human-wildlife conflict, triggering the retaliatory killing of large carnivores. Although domestic dogs (Canis familiaris) contribute to livestock depredation, blame primarily falls on wild predators. Dogs can also transmit pathogens between wildlife, domestic animals, and humans. Therefore, the presence of free-ranging dogs can have negative consequences for biodiversity conservation, smallholder economy, food supply, and public health, four of the United Nations' Sustainable Developed Goals (SDGs) for 2030. In Ecuador, where livestock sustains rural households, retaliatory poaching threatens Andean bear (Tremarctos ornatus), jaguar (Panthera onca), and puma (Puma concolor) populations. However, the role of dogs in these incidents remains underexplored. The present study evaluates the possibility of reliable molecular identification of predatory species from DNA traces in bite wounds. Our results revealed the presence of dog saliva on four out of six livestock carcasses presumably attacked by wild predators. These findings highlight the importance of rectifying misinformation about large carnivores in Ecuador and the need to control dog populations. We recommend that local administrations incorporate DNA analysis into livestock predation events to examine how common the problem is, and to use the analysis to develop conflict mitigation strategies which are essential for the conservation of large carnivores.

Andrographolide Ameliorates Inflammatory Changes Induced by D-Lactate in Bovine Fibroblast-like Synoviocytes.

During acute ruminal acidosis, the manifestation of aseptic polysynovitis and lameness in cattle has been observed. Evidence suggests that joint inflammation can be attributed to the metabolic alterations induced by D-lactate in fibroblast-like synoviocytes (FLSs). We aimed to investigate whether andrographolide could mitigate the inflammation and metabolic alterations induced by D-lactate in bovine fibroblast-like synoviocytes (bFLSs). To assess this, bFLSs were cultured in the presence or absence of andrographolide. We evaluated its potential interference with the expression of proinflammatory cytokines, COX-2, HIF-1α, and LDHA using RT-qPCR. Furthermore, we investigated its potential interference with PI3K/Akt signaling and IκBα degradation through immunoblotting and flow cytometry, respectively. Our observations revealed that andrographolide reduced the elevation of IL-6, IL-8, COX-2, HIF-1α, and LDHA induced by D-lactate. Additionally, andrographolide demonstrated interference with the PI3K/Akt and NF-κB pathways in bFLSs. In conclusion, our findings suggest that andrographolide can potentially reverse the inflammatory effects and metabolic changes induced by D-lactate in bFLSs, showing promise as a therapeutic intervention for managing these conditions associated with lameness.

Neural tube defects and epigenetics: role of histone post-translational histone modifications.

Neural tube defects (NTDs) are the most common congenital anomalies of the CNS. It is widely appreciated that both genetic and environmental factors contribute to their etiology. The inability to ascribe clear genetic patterns of inheritance to various NTD phenotypes suggests it is possible that epigenetic mechanisms are involved in the etiology of NTDs. In this context, the contribution of DNA methylation as an underlying contributing factor to the etiology of NTDs has been extensively reviewed. Here, an updated accounting of the evidence linking post-translational histone modifications to these birth defects, relying heavily upon studies in humans, and the possible molecular implications inferred from reports based on cellular and animal models, are presented.

d-lactate-induced ETosis in cattle polymorphonuclear leucocytes is dependent on the release of mitochondrial reactive oxygen species and the PI3K/Akt/HIF-1 and GSK-3ß pathways.

d-lactate is a metabolite originating from bacterial metabolism that accumulates as a result of dietary disturbances in cattle, leading to ruminal acidosis. d-lactate exerts functions as a metabolic signal inducing metabolic reprogramming and extracellular trap (ET) release in polymorphonuclear leucocytes (PMNs). We previously demonstrated that d-lactate induces metabolic reprogramming via hypoxia-induced factor 1 alpha (HIF-1α) stabilization in bovine fibroblast-like synoviocytes (FLSs). In the present study, the role of HIF-1 in ET formation induced by d-lactate was assessed. HIF-1α stabilization in PMNs was controlled by mitochondrial reactive oxygen species (mtROS) release. Furthermore, inhibition of mitochondrial complex I and scavenging of mtROS decreased d-lactate-triggered ETosis. d-lactate-enhanced HIF-1α accumulation was dependent on the PI3K/Akt pathway but independent of GSK-3ß activity. Pharmacological blockade of the PI3K/Akt/HIF-1 and GSK-3ß axes inhibited d-lactate-triggered ETosis and downregulated PDK1 and LDHA expression. However, only GSK-3ß inhibition decreased the expression of glycogen metabolism enzymes and prevented the decline in glycogen stores induced by d-lactate exposure. The results of this study suggest that mtROS, PI3K/Akt/HIF-1 and GSK-3ß axes regulate carbohydrate metabolism adaptations that support d-lactate-induced ET formation in cattle.

ATP Induces Interleukin-8, Intracellular Calcium Release, and ERK1/2 Phosphorylation in Bovine Endometrial Cells, Partially through P2Y Receptors.

The bovine endometrium has an important defensive role in the postpartum period that acts when an inflammatory process associated with tissue damage or infection by bacteria is produced. Endometrial cells release cytokines and chemokines that recruit inflammatory cells, which release danger-associated molecular patterns (DAMPs), such as adenosine triphosphate (ATP), and initiate and regulate the inflammatory response. However, the role of ATP in bovine endometrial cells is unclear. The aim of this study was to determine the effect of ATP on interleukin-8 (IL-8) release, intracellular calcium mobilization, ERK1/2 phosphorylation, and the role of P2Y receptors, in bovine endometrial cells. Bovine endometrial (BEND) cells were incubated with ATP and the IL-8 release was determined by the ELISA assay. ATP of 50 and 100 µM significantly increased IL-8 released in BEND cells (50 µM: 23.16 ± 3.82 pg/mL, p = 0.0018; 100 µM: 30.14 ± 7.43 pg/mL, p = 0.0004). ATP (50 µM) also induced rapid intracellular calcium mobilization in Fura-2AM-loaded BEND cells, as well as ERK1/2 phosphorylation (ratio 1.1 ± 0.04, p = 0.0049). Suramin (50 µM), a pan-antagonist of P2Y receptors, partially reduced the intracellular calcium mobilization, ERK1/2 phosphorylation (ratio 0.83 ± 0.08, p = 0.045), and IL-8 release (9.67 ± 0.02 pg/mL, p = 0.014) induced by ATP. Finally, BEND cells expressed higher mRNA levels of P2Y1 and P2Y2 purinergic subtype receptors, and lower levels of P2Y11 and P2Y12 receptors, as determined by RT-qPCR. In conclusion, these results showed that ATP activates pro-inflammatory responses in BEND cells, which are partially mediated via P2Y receptors, and BEND cells express the mRNA of subtypes of P2Y receptors, which could have a key role in bovine endometrial inflammation.

Bovine tumor necrosis factor-alpha Increases IL-6, IL-8, and PGE2 in bovine fibroblast-like synoviocytes by metabolic reprogramming.

Lameness is a common condition in dairy cattle caused by infectious or noninfectious agents. Joint lesions are the second most common cause of lameness and can be diagnosed in association with the presentation of digit injuries. Fibroblast-like synoviocyte (FLS) are predominant cells of synovia and play a key role in the pathophysiology of joint diseases, thus increasing the expression of proinflammatory mediators. Tumor necrosis factor-alpha (TNF-α) is a potent proinflammatory cytokine involved in cyclooxygenase 2 (COX-2) and proinflammatory cytokine expression in FLS. Previously, TNF-α was demonstrated to increase hypoxia-inducible Factor 1 (HIF-1), a transcription factor that rewires cellular metabolism and increases the expression of interleukin (IL)-6 in bovine FLS (bFLS). Despite this, the proinflammatory effects of TNF-α in bFLS on metabolic reprogramming have been poorly studied. We hypothesized that TNF-α increases glycolysis and in this way controls the expression of IL-6, IL-8, and COX-2 in bFLS. Results first, gas chromatography/mass spectrometry (GC/MS)-based untargeted metabolomics revealed that bTNF-α altered the metabolism of bFLS, increasing glucose, isoleucine, leucine, methionine, valine, tyrosine, and lysine and decreasing malate, fumarate, α-ketoglutarate, stearate, palmitate, laurate, aspartate, and alanine. In addition, metabolic flux analysis using D-glucose-13C6 demonstrated an increase of pyruvate and a reduction in malate and citrate levels, suggesting a decreased flux toward the tricarboxylic acid cycle after bTNF-α stimulation. However, bTNF-α increased lactate dehydrogenase subunit A (LDHA), IL-6, IL-8, IL-1ß and COX-2 expression, which was dependent on glycolysis and the PI3K/Akt pathway. The use of FX11 and dichloroacetate (DCA), an inhibitor of LDHA and pyruvate dehydrogenase kinase (PDK) respectively, partially reduced the expression of IL-6. Our results suggest that bTNF-α induces metabolic reprogramming that favors glycolysis in bFLS and increases IL-6, IL-8, IL-1ß and COX-2/PGE2.

Tamoxifen triggers the in vitro release of neutrophil extracellular traps in healthy horses.

Neutrophils display an array of biological functions including the formation of neutrophil extracellular traps (NETs), web-like structures specialized in trapping, neutralizing, killing and preventing microbial dissemination within the host. However, NETs contribute to a number of inflammatory pathologies, including severe equine asthma. Tamoxifen (TX) is a selective estrogen receptor modulator which belongs to the triphenylethyllenes group of molecules, and which is used as a treatment in all stages of estrogen-positive human breast cancer. Our previous results suggest that tamoxifen can modulate neutrophil functionality and promote resolution of inflammation; this would partly explain the clinical beneficial effect of this drug in horses with airway inflammation. Enhanced NETs production has been reported with tamoxifen use in humans, but minimal data exists regarding the drug's effect on NETs in horses. The aim of this study is to assess the in vitro effect of TX on NETs formation from peripheral blood of healthy horses. Five clinically healthy mixed-breed adult horses were enrolled in the study. For this, cellular free DNA quantification, immunofluorescence for the visualization of NETs, assessment of different types of NETs, and detection of mitochondrial superoxide. TX induced NETs formation at a concentration of 10 uM. Our results show that only two types of NETs were induced by TX: 95% spread NETs (sprNETs) and 5% aggregated NETs (aggNETs). Furthermore, induction of these NETs could be influenced by mitochondrial ROS. Future research should involve an In vivo study of horses with severe asthma and TX treatment, to evaluate BALF neutrophil NET formation. In conclusion, this in vitro study suggests that the resolution of inflammation by TX in horses with airway inflammation is due to inhibition of other neutrophilic functions but not to NET formation.

An exploratory double-blind, randomized, placebo-controlled study to assess the efficacy of CitruSlim on body composition and lipid parameters in obese individuals.

The prevalence of obesity in developing and developed countries has been well recognized, and the worldwide obesity rates have nearly tripled since 1975, according to the World Health Organization. CitruSlim, a standardized product containing a blend of Citrus bergamia and Eurycoma longifolia, can reduce cortisol, cholesterol, triglycerides, and hyperglycemia. These properties can contribute to reduction in body weight or body mass index (BMI) in obese patients. A randomized, double-blind, placebo-controlled clinical study was designed to evaluate the efficacy and tolerability of CitruSlim in body weight management in obese individuals, and the results were compared with that of placebo. A total of 97 participants were allocated, randomized, and treated with CitruSlim high-dose (HD, 400 mg), CitruSlim low-dose (LD, 200 mg), and placebo for 112 days. At the end of the study, CitruSlim HD and CitruSlim LD significantly reduced BMI compared to the placebo group and were well tolerated; however, it did not improve parameters associated with dyslipidemia and metabolic disturbances. The study findings suggested that CitruSlim was effective in reducing body weight in obese patients.

[Consensus of the Genetics Branch of the Chilean Society of Pediatrics on the prioritization of people with Down syndrome and rare diseases for vaccination against SARS-CoV-2]. / Consenso de la Rama de Genética de la Sociedad Chilena de Pediatría sobre priorización de personas con Síndrome de Down y otras condiciones poco frecuentes en la Campaña de Vacunación COVID-19.

In the framework of the vaccination campaign against the SARS-CoV-2 virus, the Chilean Ministry of Health requested advice from the Genetics Branch of the Chilean Society of Pediatrics, to define the level of prioritization for people with Down Syndrome . A panel of geneticists worked on the development of this consensus, in which not only patients with Down syndrome were included, but the search was extended to patients with other types of disabilities, in both pediatric and adult ages in or der to contribute to the development of public health measures against the COVID-19 pandemic. The consensus concludes that, given the prevalence of comorbidities associated with Down syndrome, the higher incidence of cases with severe COVID-19 in this population group and a higher mortality, individuals with trisomy 21 should be considered as a high-risk population, and therefore, vaccina tion against SARS-CoV-2 should have a high priority for all people with Down syndrome regardless of their age (except for the age limit established by the clinical trials of each vaccine), and should be preceded only by the groups of health personnel and adults aged > 60-65 years. Likewise, this group of experts urges health authorities to include people with intellectual disabilities and related conditions as a priority population (other chromosomal abnormalities other than Down syndrome, intellectual disability, congenital anomalies and conditions that cause disability with microcephaly), as well as the caregivers of people with this type of conditions. Vaccination in children with this type of disorders should be considered as part of the first priority group, once safe vaccines against SARS-CoV-2 are available for use in children and adolescents.

Chilean dentists' knowledge of hearing loss generated by occupational noise exposure / Conocimiento de odontólogos chilenos sobre la pérdida auditiva generada por exposición ocupacional al ruido

Abstract Introduction: Dentists are a population at high risk of hearing loss due to their constant exposure to instruments that can generate noise of up to 100 dB during their practice. Objective: To determine the level of knowledge of dentists working in Chile regarding hearing loss caused by exposure to noise generated by dental instruments. Materials and methods: A cross-sectional study was conducted in 114 dentists, who completed a virtual survey of 22 questions regarding the perception and level of knowledge about hearing loss due to exposure to loud noises and about national regulations on occupational noise exposure. Differences between perception and knowledge levels were evaluated taking into account the years of professional practice and the average weekly workload in dental treatment rooms. Descriptive and inferential statistics (Chi-squared test) were used for data analysis. Results: Most participants were Chilean (99.1%); 58.8% were women, and 72.8% had less than 10 years of professional experience. In addition, 97.4% were unaware of national regulations on occupational noise exposure and 50% of the sample reported having experienced hearing loss; of these, 57.9% (n = 32) associated it with their practice. Conclusions: A very low percentage of participants knew that there are regulations regarding occupational noise exposure. For this reason, it is important that, both during their training and their professional practice, dentists in Chile have greater access to information about these regulations and hearing protection measures.

Resumen Introducción. Los odontólogos son una población con un alto riesgo de desarrollar pérdida auditiva debido a la constante exposición a instrumentales que deben usar en su práctica profesional y que pueden generar ruidos de hasta 100 dB. Objetivo. Determinar el nivel de conocimiento de odontólogos laboralmente activos en Chile respecto a la pérdida auditiva causada por la exposición al ruido generado por maquinarias dentales. Materiales y métodos. Estudio transversal realizado en 114 odontólogos, quienes diligenciaron una encuesta virtual de 22 preguntas relativas a la percepción y el nivel de conocimiento sobre pérdida auditiva por exposición a ruidos fuertes y sobre la normativa nacional respecto a exposición ocupacional al ruido. Se evaluaron las diferencias entre percepción y niveles de conocimiento según los años de ejercicio profesional y la carga promedio de trabajo semanal en boxes de atención. Para el análisis de los datos se utilizó estadística descriptiva e inferencial (prueba de chi-cuadrado). Resultados. La mayoría de participantes eran chilenos (99.1%); el 58.8% fueron mujeres, y el 72.8% tenía menos de 10 años de ejercicio profesional. Además, el 97.4% desconocía las regulaciones nacionales sobre exposición ocupacional al ruido y el 50% reportó haber experimentado pérdida auditiva; de estos, 57.9% (n=32) lo asoció a su profesión. Conclusiones. Un muy bajo porcentaje de los participantes sabe que hay disposiciones sobre exposición ocupacional al ruido, por lo que es importante que, tanto en su formación, como durante su ejercicio profesional, los odontólogos en Chile tengan un mayor acceso a información relativa a estas normativas y a medidas ocupacionales de protección auditiva.

Rheumatoid meningitis: A systematic review and meta-analysis.

BACKGROUND AND PURPOSE: Rheumatoid meningitis (RM) is a neurological complication of rheumatoid arthritis (RA). Current evidence is based on case reports and partial reviews. METHODS: This is a systematic review and meta-analysis following the PRISMA statement. The aim is to describe the characteristics of the disease, including clinical, imaging and laboratory findings, treatment, outcomes and prognosis reported in the literature. RESULTS: In all, 103 studies with 130 cases were included. RM affected adults with an average age of 62 years, with or without a previous RA diagnosis. RA activity and time with the disease were associated with a worse prognosis. Most common clinical manifestations were transient focal neurological signs (64.6%), systemic symptoms (51.3%), episodic headache (50.4%) and neuropsychiatric alterations (47.7%). Joint manifestations were present in only 27.4% of cases. Brain magnetic resonance imaging showed unilateral or bilateral involvement, predominantly frontoparietal. Both pachymeninges and leptomeninges were affected, the latter more frequently (82.88%). The laboratory findings included increased levels of rheumatoid factor (89.71%), anti-cyclic citrullinated peptide (89.47%), C-reactive protein (82.54%) and erythrocyte sedimentation rate (81.81%). Cerebrospinal fluid analysis showed an increase in the protein level (76.14%), with pleocytosis (85.19%) of mononuclear predominance (89.19%). Biopsy was performed in 72.52% of the patients. Corticosteroid pulse therapy was the main induction therapy. Disease relapse occurred in 31.17% of patients, whilst 54.54% had a full recovery. CONCLUSIONS: Rheumatoid meningitis must be considered in adult patients with or without RA diagnosis, high-dose corticosteroid induction therapy should be installed and maintenance therapy plays a key role. It is not recommended to use anti-TNF as an induction therapy. Nowadays, RM has a significantly better outcome. These findings may aid clinicians in timely RM diagnosis and treatment, thus improving its outcomes.

Limited sexual segregation in a dimorphic avian scavenger, the Andean condor.

Sexual segregation is widely reported among sexually dimorphic species and generally attributed to intraspecific competition. Prey diversity and human activities can reinforce niche segregation by increasing resource heterogeneity. Here, we explored trophic and spatial sexual segregation in the only avian scavenger that exhibits pronounced sexual size dimorphism (up to 50% difference in body mass) and a highly despotic social system, the Andean condor (Vultur gryphus). We predicted that larger and dominant males would exclude smaller and subordinate females from high-quality resources, leading to sexual segregation particularly in human-dominated landscapes showing increased prey diversity. We compared resource use between females and males across six sites in Argentina featuring a range of prey diversity via stable isotopes analysis of molted feathers (n = 141 individuals). We then focused on two sites featuring contrasting levels of prey diversity and quantified assimilated diet via stable isotopes and space use via GPS monitoring (n = 23 and 12 tagged individuals). We found no clear differences in isotopic niche space, individual variation in isotopic signature, or assimilated diet between females and males. However, there were differences in foraging locations between sexes, with females apparently using areas of fewer food resources more frequently than males. Local conditions defined the dynamics of fine-scale sexual differences in foraging sites; yet, unpredictable and ephemeral carrion resources likely prevent segregation by sexes at the landscape scale. Our study highlights complex dynamics of sexual segregation in vultures and the relevancy of analyses under multiple spatial-temporal scales to explore segregation in social species.

Piscirickettsia salmonis-Triggered Extracellular Traps Formation as an Innate Immune Response of Atlantic Salmon-Derived Polymorphonuclear Neutrophils.

Extracellular traps (ETs) are webs of DNA, citrullinated histones, anti-microbial peptides, and proteins that were not previously reported in Atlantic salmon (Salmo salar). ETs are mainly released from polymorphonuclear neutrophils (PMN) and are considered a novel PMN-derived effector mechanism against different invasive pathogens. Here, we showed that Atlantic salmon-derived PMN released ETs-like structures in vitro in response to highly pathogenic facultative intracellular rickettsial bacteria Piscirickettsia salmonis. PMN were isolated from pre-smolt Atlantic salmon and stimulated in vitro with oleic acid and P. salmonis. Extracellular DNA was measured using the PicoGreen™ dye, while immunofluorescence image analysis was used to confirm the classical components of salmonid-extruded ETs. Future studies are required to better understand the role of Atlantic salmon-derived ETs orchestrating innate/adaptive immunity and the knowledge on regulation pathways involved in this cell death process. Thus, comprehension of salmonid-derived ETs against P. salmonis might represent novel alternative strategies to improve host innate defense mechanisms of farmed salmon against closely related rickettsial bacteria, as a complement to disease prevention and control strategies.

Metabolic Reprogramming and Inflammatory Response Induced by D-Lactate in Bovine Fibroblast-Like Synoviocytes Depends on HIF-1 Activity.

Acute ruminal acidosis (ARA) occurs after an excessive intake of rapidly fermentable carbohydrates and is characterized by the overproduction of D-lactate in the rumen that reaches the bloodstream. Lameness presentation, one of the primary consequences of ARA in cattle, is associated with the occurrence of laminitis and aseptic polysynovitis. Fibroblast-like synoviocytes (FLS) are predominant cells of synovia and play a key role in the pathophysiology of joint diseases, thus increasing the chances of the release of pro-inflammatory cytokines. Increased D-lactate levels and disturbances in the metabolism of carbohydrates, pyruvates, and amino acids are observed in the synovial fluid of heifers with ARA-related polysynovitis prior to neutrophil infiltration, suggesting an early involvement of metabolic disturbances in joint inflammation. We hypothesized that D-lactate induces metabolic reprogramming, along with an inflammatory response, in bovine exposed FLS. Gas chromatography-mass spectrometry (GC-MS)-based metabolomics revealed that D-lactate disrupts the metabolism of bovine FLS, mainly enhancing glycolysis and gluconeogenesis, pyruvate metabolism, and galactose metabolism. The reverse-transcription quantitative PCR (RT-qPCR) analysis revealed an increased expression of metabolic-related genes, including hypoxia-inducible factor 1 (HIF-1)α, glucose transporter 1 (Glut-1), L-lactate dehydrogenase subunit A (L-LDHA), and pyruvate dehydrogenase kinase 1 (PDK-1). Along with metabolic disturbances, D-lactate also induced an overexpression and the secretion of IL-6. Furthermore, the inhibition of HIF-1, PI3K/Akt, and NF-κB reduced the expression of IL-6 and metabolic-related genes. The results of this study reveal a potential role for D-lactate in bFLS metabolic reprogramming and support a close relationship between inflammation and metabolism in cattle.

Role of Lactate in Inflammatory Processes: Friend or Foe.

During an inflammatory process, shift in the cellular metabolism associated with an increase in extracellular acidification are well-known features. This pH drop in the inflamed tissue is largely attributed to the presence of lactate by an increase in glycolysis. In recent years, evidence has accumulated describing the role of lactate in inflammatory processes; however, there are differences as to whether lactate can currently be considered a pro- or anti-inflammatory mediator. Herein, we review these recent advances on the pleiotropic effects of lactate on the inflammatory process. Taken together, the evidence suggests that lactate could exert differential effects depending on the metabolic status, cell type in which the effects of lactate are studied, and the pathological process analyzed. Additionally, various targets, including post-translational modifications, G-protein coupled receptor and transcription factor activation such as NF-κB and HIF-1, allow lactate to modulate signaling pathways that control the expression of cytokines, chemokines, adhesion molecules, and several enzymes associated with immune response and metabolism. Altogether, this would explain its varied effects on inflammatory processes beyond its well-known role as a waste product of metabolism.

Andrographolide, an Anti-Inflammatory Multitarget Drug: All Roads Lead to Cellular Metabolism.

Andrographolide is a labdane diterpene and the main active ingredient isolated from the herb Andrographis paniculata. Andrographolide possesses diverse biological effects including anti-inflammatory, antioxidant, and antineoplastic properties. Clinical studies have demonstrated that andrographolide could be useful in therapy for a wide range of diseases such as osteoarthritis, upper respiratory diseases, and multiple sclerosis. Several targets are described for andrographolide, including the interference of transcription factors NF-κB, AP-1, and HIF-1 and signaling pathways such as PI3K/Akt, MAPK, and JAK/STAT. In addition, an increase in the Nrf2 (nuclear factor erythroid 2-related factor 2) signaling pathway also supports its antioxidant and anti-inflammatory properties. However, this scenario could be more complex since recent evidence suggests that andrographolide targets can modulate glucose metabolism. The metabolic effect of andrographolide might be the key to explaining the diverse therapeutic effects described in preclinical and clinical studies. This review discusses some of the most recent evidence about the anti-inflammatory and metabolic effects of andrographolide.

D-Lactate Increases Cytokine Production in Bovine Fibroblast-Like Synoviocytes via MCT1 Uptake and the MAPK, PI3K/Akt, and NFκB Pathways.

Acute ruminal acidosis (ARA) is caused by the excessive intake of highly fermentable carbohydrates, followed by the massive production of D-lactate and the appearance of neutrophilic aseptic polysynovitis. Bovines with ARA develop different lesions, such as ruminitis, polioencephalomalacia (calves), liver abscess and lameness. Lameness in cattle with ARA is closely associated with the presence of laminitis and polysynovitis. However, despite decades of research in bovine lameness as consequence of ruminal acidosis, the aetiology and pathogenesis remain unclear. Fibroblast-like synoviocytes (FLSs) are components of synovial tissue, and under pathological conditions, FLSs increase cytokine production, aggravating inflammatory responses. We hypothesized that D-lactate could induce cytokine production in bovine FLSs. Analysis by qRT-PCR and ELISA revealed that D-lactate, but not L-lactate, increased the expression of IL-6 and IL-8 in a monocarboxylate transporter-1-dependent manner. In addition, we observed that the inhibition of the p38, ERK1/2, PI3K/Akt, and NF-κB pathways reduced the production of IL-8 and IL-6. In conclusion, our results suggest that D-lactate induces an inflammatory response; this study contributes to the literature by revealing a potential key role of D-lactate in the polysynovitis of cattle with ARA.

Metabolomics analysis of bronchoalveolar lavage fluid samples in horses with naturally-occurring asthma and experimentally-induced airway inflammation.

The present work characterized the metabolomic profile of bronchoalveolar lavage fluid (BALF) in healthy horses, experimentally-induced airway inflammation by lipopolysaccharide (LPS) nebulization, and naturally-occurring asthma (n = 3 in each group). All animals underwent clinical and upper airway endoscopic examinations, and bronchoalveolar lavage. BALF supernatant samples were subjected to metabolic analysis based on gas chromatography-mass spectrometry (GC-MS). Overall, 67 peaks were obtained from BALF GC-MS analysis, corresponding to 53 metabolites which were categorized according to chemical class, such as organic acids, fatty acids, nucleosides or their derivatives, amino acids, peptides or their derivatives, carbohydrates, and other compounds. Our results showed that the airway inflammation induction model with LPS produced the same pattern of metabolite changes as in horses with naturally occurring asthma. Metabolic pathway analysis was done by means of Fisher's exact test, for detection of metabolites over-represented in asthma affected-horses and LPS-induced airway inflammation as compared with healthy horses. The most significant altered metabolic pathways were fatty acid biosynthesis, galactose metabolism and citrate cycle. These results suggest that the airway inflammation induction model with LPS is a good study model for asthma-affected horses, due to the similarity of the profile of inflammatory cells (specifically neutrophils) and similar metabolic alterations found in BALF that occur during the inflammatory process of the airways. Further research may increase understanding of metabolomics disturbances and their significance in the pathogenesis of equine asthma.

ß-hydroxybutyrate and hydroxycarboxylic acid receptor 2 agonists activate the AKT, ERK and AMPK pathways, which are involved in bovine neutrophil chemotaxis.

Elevated plasma concentrations of the ketone body ß-hydroxybutyrate (BHB), an endogenous agonist of the hydroxycarboxylic acid receptor 2 (HCA2), is associated with an increased incidence of inflammatory diseases during lactation in dairy cows. In the early stages of this pathology, an increase in neutrophil recruitment is observed; however, the role of BHB remains elusive. This study characterized the effect of BHB and synthetic agonists of the HCA2 receptor on bovine neutrophil chemotaxis and the signaling pathways involved in this process. We demonstrated that treatment with BHB concentrations between 1.2 and 10 mM and two full selective agonists of the HCA2 receptor, MK-1903 and nicotinic acid, increased bovine neutrophil chemotaxis. We also observed that BHB and HCA2 agonists induced calcium release and phosphorylation of AKT, ERK 1/2 and AMPKα. To evaluate the role of these pathways in bovine neutrophil chemotaxis, we used the pharmacological inhibitors BAPTA-AM, pertussis toxin, U73122, LY294002, U0126 and compound C. Our results suggest that these pathways are required for HCA2 agonist-induced bovine neutrophil chemotaxis in non-physiological condition. Concentrations around 1.4 mM of BHB after calving may exert a chemoattractant effect that is key during the onset of the inflammatory process associated with metabolic disorders in dairy cows.

Oleic and Linoleic Acids Induce the Release of Neutrophil Extracellular Traps via Pannexin 1-Dependent ATP Release and P2X1 Receptor Activation.

Non-esterified fatty acids (NEFAs) such as oleic acid (OA) and linoleic acid (LA) are associated with a higher incidence of infectious diseases such as metritis and mastitis during the bovine peripartum. Fatty acids can induce an increase in the release of ATP, and changes in the expression levels of purinergic receptors in bovine polymorphonuclears (PMN) during peripartum have also been reported. PMN respond to inflammatory processes with production of ROS, release of proteolytic and bactericidal proteins, and formation of neutrophil extracellular traps (NETs). NETs formation is known to require ATP production through glycolysis. Studies have shown that the above-mentioned metabolic changes alter innate immune responses, particularly in PMN. We hypothesized that NEFAs induce the formation of NETs through ATP release by Pannexin 1 and activation of purinergic receptors. In this study, we found that OA and LA induce NET formation and extracellular ATP release. Carbenoxolone, a pannexin-1 (PANX1) inhibitor, reduced OA- and LA-induced ATP release. We also found that P2X1, P2X4, P2X5, P2X7, and PANX1 were expressed at the mRNA level in bovine PMN. Additionally, NEFA-induced NET formation was completely abolished with exposure to NF449, a P2X1 antagonist, and partially inhibited by treatment with etomoxir, an inhibitor of fatty acid oxidation (FAO). Our results suggest that OA and LA induce NET formation and ATP release via PANX1 and activation of P2X1. These new data contribute to explaining the effects of NEFA high concentrations during the transition period of dairy cattle and further understanding of pro-inflammatory effects and outcome of postpartum diseases.