Molecular evolution of epididymal lipocalin genes localized on mouse chromosome 2

Producción CientíficaWe previously identified two murine secretory proteins, mE-RABP(Lcn5) and mEP17(Lcn8), belonging to the lipocalin family and specifically expressed in the epididymis. The genes are contiguous and localized on mouse chromosome 2. We now show that five other related lipocalin genes, Lcn9, Lcn10, Lcn11, Lcn12, and Lcn13, that evolved by in situ tandem duplication are present on the same locus. Lcn9, Lcn10, Lcn12, and Lcn13 genes, like Lcn5 and Lcn8 genes, are specifically expressed in the mouse epididymis. However, each gene has a distinct spatial expression within the epididymis and different regulation. Analysis of the human genome sequence shows the presence of genes encoding lipocalins with genomic organization, chromosomal arrangement, and orientation similar to that of the corresponding murine genes, indicating that the epididymal cluster is evolutionary conserved. A phylogenetic analysis of the new epididymal proteins reveals their spread position in the lipocalin protein family tree. This suggests the preservation of the regulatory sequences, while protein sequences have greatly diverged, reflecting functional diversity and possibly multifunctionality. In terms of the cluster ancestry, epididymal expression possibly appeared in a PGDS-like lipocalin in amniotes, and the duplications generating the cluster occurred at least in the common ancestor of rodents and primates. The presence and conservation of a cluster of five genes encoding epididymal lipocalins, differently regulated and regionalized in the epididymis, strongly suggests that these proteins may play an important role for male fertility

Molecular cloning and hormonal regulation of a murine epididymal retinoic acid-binding protein messenger ribonucleic acid

A complementary DNA encoding the mouse epididymal secretory protein MEP 10 (mouse epididymal protein 10) was cloned and is now renamed murine epididymal retinoic acid binding protein (mE-RABP). The analysis of the predicted primary amino acid sequence showed that mE-RABP has a 75% identity with rat ESP I (epididymal secretory protein I), another epididymal retinoic acid-binding protein. The homology strongly suggests that mE-RABP is the mouse orthologue of rat ESP I. A computer analysis of the predicted three- dimensional structure confirmed that mE-RABP can accommodate retinoic acid as ligand. In the rat, ESP I messenger RNA (mRNA) is expressed in the efferent ducts and in the entire caput epididymidis. However, in the mouse, the expression of a 950-bp mE-RABP mRNA was detected only in principal cells of the mid/distal caput epididymidis, suggesting that the regulation of region- specific expression is different in rat and mouse. Northern blot analyses showed that mE-RABP gene expression is no longer detected 10 days after castration but progressively rebounds between days 15 and 60. However, mE- RABP protein could not be detected by Western blot 30 days after castration. Androgen replacement, begun 5 days after castration and continued for 4 days restored significant expression of mE-RABP mRNA. Efferent duct ligation for 10 days did not affect gene expression. Taken together, these results indicate that mE-RABP mRNA expression is regulated by androgens but not by testicular factors. The overall similarity in the primary amino acid sequence of mE-RABP with ESP I and other members of the lipocalin superfamily suggests that they are evolutionarily related

Impaired Autophagy in CD11b+ Dendritic Cells Expands CD4+ Regulatory T Cells And Limits Atherosclerosis in Mice.

Rationale: Atherosclerosis is a chronic inflammatory disease. Recent studies have shown that dysfunctional autophagy in endothelial cells, smooth muscle cells and macrophages, plays a detrimental role during atherogenesis, leading to the suggestion that autophagy-stimulating approaches may provide benefit. Objective: Dendritic cells (DCs) are at the crossroad of innate and adaptive immune responses and profoundly modulate the development of atherosclerosis. Intriguingly, the role of autophagy in DC function during atherosclerosis and how the autophagy process would impact disease development has not been addressed. Methods and Results: Here, we show that the autophagic flux in atherosclerosis-susceptible low-density lipoprotein receptor deficient (Ldlr-/-) mice is substantially higher in splenic and aortic DCs compared to macrophages, and is further activated under hypercholesterolemic conditions. RNA sequencing and functional studies on selective cell populations reveal that disruption of autophagy through deletion of Atg16l1 differentially affects the biology and functions of DC subsets in Ldlr-/- mice under high fat diet. Atg16l1 deficient CD11b+ DCs develop a TGF-beta-dependent tolerogenic phenotype and promote the expansion of regulatory T cells (Tregs), whereas no such effects are seen with Atg16l1 deficient CD8alpha+ DCs. Atg16l1 deletion in DCs (all CD11c-expressing cells) expands aortic Tregs in vivo, limits the accumulation of T helper cells type 1 (Th1), and reduces the development of atherosclerosis in Ldlr-/- mice. In contrast, no such effects are seen when Atg16l1 is deleted selectively in conventional CD8alpha+ DCs and CD103+ DCs. Total T cell or selective Treg cell depletion abrogates the atheroprotective effect of Atg16l1 deficient DCs. Conclusions: In contrast to its pro-atherogenic role in macrophages, autophagy disruption in DCs induces a counter-regulatory response that maintains immune homeostasis in Ldlr-/- mice under high fat diet and limits atherogenesis. Selective modulation of autophagy in DCs could constitute an interesting therapeutic target in atherosclerosis.This study was supported by the British Heart Foundation (CH/10/001/27642 and Grant No. 1659), and the European HEALTH 2013.1.3-3 programm

Interleukin-6 Receptor Signaling and Abdominal Aortic Aneurysm Growth Rates.

BACKGROUND: The Asp358Ala variant (rs2228145; A>C) in the IL (interleukin)-6 receptor ( IL6R) gene has been implicated in the development of abdominal aortic aneurysms (AAAs), but its effect on AAA growth over time is not known. We aimed to investigate the clinical association between the IL6R-Asp358Ala variant and AAA growth and to assess the effect of blocking the IL-6 signaling pathway in mouse models of aortic aneurysm rupture or dissection. METHODS: Using data from 2863 participants with AAA from 9 prospective cohorts, age- and sex-adjusted mixed-effects linear regression models were used to estimate the association between the IL6R-Asp358Ala variant and annual change in AAA diameter (mm/y). In a series of complementary randomized trials in mice, the effect of blocking the IL-6 signaling pathways was assessed on plasma biomarkers, systolic blood pressure, aneurysm diameter, and time to aortic rupture and death. RESULTS: After adjusting for age and sex, baseline aneurysm size was 0.55 mm (95% CI, 0.13-0.98 mm) smaller per copy of the minor allele [C] of the Asp358Ala variant. Change in AAA growth was -0.06 mm per year (-0.18 to 0.06) per copy of the minor allele; a result that was not statistically significant. Although all available worldwide data were used, the genetic analyses were not powered for an effect size as small as that observed. In 2 mouse models of AAA, selective blockage of the IL-6 trans-signaling pathway, but not combined blockage of both, the classical and trans-signaling pathways, was associated with improved survival ( P<0.05). CONCLUSIONS: Our proof-of-principle data are compatible with the concept that IL-6 trans-signaling is relevant to AAA growth, encouraging larger-scale evaluation of this hypothesis

Structural organization and regulation of the gene for the androgen-dependent glutathione peroxidase-like protein specific to the mouse epididymis

International audienceGenomic clones containing the gene for the glutathione peroxidase-like androgen-regulated murine epididymal protein of 24 kilodaltons (arMEP24) were isolated. A 9-kilobase DNA fragment was sequenced and found to contain the entire coding region of the gene, which is divided into five exons. The exact sizes and boundaries of the exon blocks were deduced by comparison with the cDNA sequence. One major and four weak transcription initiation sites in the epididymis were localized by primer extension. The promoter of the gene does not contain a conventional TATA box immediately up-stream of the start site; rather, the sequence TATCA occurs at residue -35. Two CAAT boxes in opposite orientation and two putative binding sites for the transcription factor Sp1 were identified up-stream of the TATA-like box. To localize the cis-acting sequences responsible for androgen regulation of expression, fragments of the arMEP24 gene promoter region were cloned in front of the luciferase (LUC) reporter gene and cotransfected with an androgen receptor expression vector into CV-1 cells in a transient assay. LUC activities of CV-1 cells grown in the presence of various concentrations of 5 alpha-dihydrotestosterone were compared to LUC activities of untreated controls. The DNA fragment containing up to 200 nucleotides up-stream from the major transcription start site was sufficient for the full promoter activity, but not for the responsiveness to androgen induction. Depending on the 5 alpha-dihydrotestosterone concentration, a 2- to 4-fold induction of LUC activity was found if a -1797 to -167 arMEP24 gene fragment was used linked to the reporter gene driven by either the homologous promoter or the heterologous thymidine kinase promoter. Two or three copies of the imperfect palindromic sequence TGTTGAgagAGAACA, found at position -896 to -882 in the gene and resembling the consensus steroid hormone-responsive element, are able to confer androgen regulation to the thymidine kinase promoter independently of their orientation. These findings support evidence that transcriptional regulation of the arMEP24 gene occurs via the sequence TGTTGAgagAGAACA. Homologies found in the sequence up-stream of the promoter with several putative binding sites for erythroid-specific trans-acting regulatory proteins are discussed. Finally, the arMEP24 gene is located by in situ hybridization in the [A2-A4] region of mouse chromosome 13

Incidence of Contrast-Induced Nephropathy and Post-Operative Outcomes in Patients Undergoing Chimney Endovascular Aortic Aneurysm Repair

Chimney endovascular aortic aneurysm repair (ch-EVAR) has become a valid alternative to treat complex aneurysms but the occurrence of contrast-induced kidney injury (CI-AKI) is poorly known. This study investigated the incidence and the impact of CI-AKI on post-operative outcomes after ch-EVAR. Consecutive patients who underwent ch-EVAR between July 2010 and 2021 were retrospectively included. CI-AKI was defined based on plasma creatinine levels within 7 days after the intervention according to the “Kidney Disease Improving Global Outcomes” (KDIGO) classification. Among 102 patients included, CI-AKI occurred in 14 cases (13.7%). The 30-day post-operative mortality and complications were significantly higher in patients who developed CI-AKI compared with those who did not (50 vs 9.1%, P =.001 and 57.1 vs 20.5%, P =.007). Over a median follow-up of 24 months (3-39), overall mortality was also significantly higher (78.6 vs 33.0%, P =.002). The pre-operative platelet-to-lymphocyte ratio (PLR) was significantly higher in patients who developed CI-AKI (224.5 vs 147.6, P =.008). CI-AKI is frequent after ch-EVAR and is associated with worse post-operative outcomes. This should increase awareness of clinicians to optimize preventive and therapeutic strategies

Characterization and evolutive clues of the GnRH receptors in Euteleosti

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A pilot study investigating the feasibility of using a fully automatic software to assess the RENAL and PADUA score

International audienc

Antithrombotic Treatment Patterns of Patients with Symptomatic Peripheral Arterial Occlusive Disease in Germany: Evidence from Health Insurance Claims Data

Objectives: Patients with peripheral arterial occlusive disease (PAOD) are at risk of worsening limb symptoms, major adverse cardiovascular events and exhibit an impaired life expectancy. There is a lack of evidence on the extent of pharmacological secondary prevention in PAOD patients. This study assesses treatment patterns of antithrombotic agents in symptomatic PAOD patients. Methods: This is a retrospective cohort study using data from the second largest insurance fund in Germany, BARMER. We included symptomatic PAOD patients undergoing in-hospital treatment with an index admission between 1 January 2010 and 31 December 2017. Outcomes were proportions of single antiplatelets (SAPT), dual antiplatelets (DAPT), vitamin-K antagonists (VKA), or direct oral anticoagulants (DOAC) in the 12 months prior and 6 months after the index hospitalization. Non-parametric cumulative incidence for competing risks was estimated to account for censoring and death after discharge from hospital stay. Patient flows were visualised by alluvial diagrams. All analyses were stratified by intermittent claudication (IC) and chronic limb-threatening ischaemia (CLTI). The protocol was registered to ClinicalTrials.gov (NCT03909022). Results: A total of 80,426 unique patient encounters were identified. Mean age was 72.7 (46.3% female). Amongst all patients, 25.6% were on SAPT, 4.1% on DAPT, 9.1% on VKA, 3.9% on DOAC, 3.9% on both antiplatelets and oral anticoagulation, and 53.3% without any antithrombotic therapy during the 12 months before index stay. The estimated cumulative incidence was 37.9% SAPT, 14.8% DAPT, 7.5% VKA, 4.3% DOAC, 7.4% both, and 28.1% without any antithrombotic therapy during the 6 months after index stay. The considerable increases in antiplatelet therapy were mainly driven by the group of patients without antithrombotics before index stay. As compared with IC, patients who suffered from CLTI received less often antiplatelets but more often anticoagulants both before and after index stay. Conclusions: Utilisation rates of antithrombotic therapy increased considerably after in-hospital treatment for PAOD. Yet, remarkably high rates of symptomatic patients without any blood-thinning therapy constitute a major concern with respect to adequate secondary prevention of PAOD patients. © 2022 by the authors