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This study aimed to investigate the potential protective effects of riociguat, a soluble guanylyl cyclase (sGC) stimulator, on kidney function and structure in rats with acute kidney injury (AKI) induced by the chemotherapeutic drug doxorubicin (DX). Rats were subjected to a single intraperitoneal injection of DX (13.5 mg/kg) on the 5th day, either alone or in combination with low-dose riociguat (3 mg/kg/day), or high-dose riociguat (10 mg/kg/day) for 8 consecutive days. Various markers related to kidney function, oxidative stress, and inflammation were measured in plasma and urine. Kidney tissues were examined histopathologically. DX-induced nephrotoxicity was characterized by increased plasma urea, creatinine, uric acid and neutrophil gelatinase-associated lipocalin (NGAL). DX also decreased creatinine clearance and albumin levels and increased urinary N-acetyl-β-D-glucosaminidase (NAG) activity. Furthermore, DX increased the inflammatory markers interleukin 1 beta (IL-1 β), interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α). DX further induced oxidative stress injury evidenced by decreased glutathione reductase (GR) activity, total antioxidant capacity (TAC), superoxide dismutase (SOD) and catalase levels and increased malondialdehyde (MDA) levels. Concomitant treatment with riociguat ameliorated these DX-induced changes with parallel histopathological improvements but the effects were more favorable with high-dose riociguat. The observed renoprotective effects of riociguat can be partly attributed to the anti-inflammatory and anti-oxidant properties of this drug., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Automated detection of specific cells in three-dimensional datasets such as whole-brain light-sheet image stacks is challenging. Here, we present DELiVR, a virtual reality-trained deep-learning pipeline for detecting c-Fos + cells as markers for neuronal activity in cleared mouse brains. Virtual reality annotation substantially accelerated training data generation, enabling DELiVR to outperform state-of-the-art cell-segmenting approaches. Our pipeline is available in a user-friendly Docker container that runs with a standalone Fiji plugin. DELiVR features a comprehensive toolkit for data visualization and can be customized to other cell types of interest, as we did here for microglia somata, using Fiji for dataset-specific training. We applied DELiVR to investigate cancer-related brain activity, unveiling an activation pattern that distinguishes weight-stable cancer from cancers associated with weight loss. Overall, DELiVR is a robust deep-learning tool that does not require advanced coding skills to analyze whole-brain imaging data in health and disease., (© 2024. The Author(s).)

Whole-body imaging techniques play a vital role in exploring the interplay of physiological systems in maintaining health and driving disease. We introduce wildDISCO, a new approach for whole-body immunolabeling, optical clearing and imaging in mice, circumventing the need for transgenic reporter animals or nanobody labeling and so overcoming existing technical limitations. We identified heptakis(2,6-di-O-methyl)-β-cyclodextrin as a potent enhancer of cholesterol extraction and membrane permeabilization, enabling deep, homogeneous penetration of standard antibodies without aggregation. WildDISCO facilitates imaging of peripheral nervous systems, lymphatic vessels and immune cells in whole mice at cellular resolution by labeling diverse endogenous proteins. Additionally, we examined rare proliferating cells and the effects of biological perturbations, as demonstrated in germ-free mice. We applied wildDISCO to map tertiary lymphoid structures in the context of breast cancer, considering both primary tumor and metastases throughout the mouse body. An atlas of high-resolution images showcasing mouse nervous, lymphatic and vascular systems is accessible at http://discotechnologies.org/wildDISCO/atlas/index.php ., (© 2023. The Author(s).)

Spatial molecular profiling of complex tissues is essential to investigate cellular function in physiological and pathological states. However, methods for molecular analysis of large biological specimens imaged in 3D are lacking. Here, we present DISCO-MS, a technology that combines whole-organ/whole-organism clearing and imaging, deep-learning-based image analysis, robotic tissue extraction, and ultra-high-sensitivity mass spectrometry. DISCO-MS yielded proteome data indistinguishable from uncleared samples in both rodent and human tissues. We used DISCO-MS to investigate microglia activation along axonal tracts after brain injury and characterized early- and late-stage individual amyloid-beta plaques in a mouse model of Alzheimer's disease. DISCO-bot robotic sample extraction enabled us to study the regional heterogeneity of immune cells in intact mouse bodies and aortic plaques in a complete human heart. DISCO-MS enables unbiased proteome analysis of preclinical and clinical tissues after unbiased imaging of entire specimens in 3D, identifying diagnostic and therapeutic opportunities for complex diseases. VIDEO ABSTRACT., Competing Interests: Declaration of interests F.T. reports receiving consulting fees from Roche Diagnostics GmbH and Cellarity, Inc., and ownership interest in Cellarity, Inc., and Dermagnostix. A.E., H.S.B., F.O., S.K., M.I.T., and M.N. have filed a patent related to robotics technologies presented in this work., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Aldosterone is released from adrenal zona glomerulosa (ZG) cells and plays an important role in Na and K homoeostasis. Mutations in the human inwardly rectifying K channel CNJ type ( KCNJ ) 5 ( KCNJ5 ) gene encoding the G-coupled inwardly rectifying K channel 4 (GIRK4) cause abnormal aldosterone secretion and hypertension. To better understand the role of wild-type (WT) GIRK4 in regulating aldosterone release, we have looked at aldosterone secretion in a Kcnj5 knockout (KO) mouse. We found that female but not male KO mice have reduced aldosterone levels compared with WT female controls, but higher levels of aldosterone after angiotensin II (Ang-II) stimulation. These differences could not be explained by sex differences in aldosterone synthase ( Cyp11B2 ) gene expression in the mouse adrenal. Using RNAseq analysis to compare WT and KO adrenals, we showed that females also have a much larger set of differentially expressed adrenal genes than males (395 compared with 7). Ingenuity Pathway Analysis (IPA) of this gene set suggested that peroxisome proliferator activated receptor (PPAR) nuclear receptors regulated aldosterone production and altered signalling in the female KO mouse, which could explain the reduced aldosterone secretion. We tested this hypothesis in H295R adrenal cells and showed that the selective PPARα agonist fenofibrate can stimulate aldosterone production and induce Cyp11b2. Dosing mice in vivo produced similar results. Together our data show that Kcnj5 is important for baseline aldosterone secretion, but its importance is sex-limited at least in the mouse. It also highlights a novel regulatory pathway for aldosterone secretion through PPARα that may have translational potential in human hyperaldosteronism., (© 2018 The Author(s).)

Loeys-Dietz syndrome (LDS) is an autosomal dominant connective tissue disorder with a range of cardiovascular, skeletal, craniofacial and cutaneous manifestations. LDS type 4 is caused by mutations in TGFβ ligand 2 (TGFB2) and based on the family pedigrees described to date, appears to have a milder clinical phenotype, often presenting with isolated aortic disease. We sought to investigate its molecular basis in a new pedigree. We identified a missense variant p.(Arg320Cys) (NM_003238.3) in a highly evolutionary conserved region of TGFB2 in a new LDS type 4 pedigree with multiple cases of aortic aneurysms and dissections. There was striking upregulation of TGFB1 and TGFB2 expression on immunofluorescent staining, and western blotting of the aortic tissue from the index case confirming the functional importance of the variant. This case highlights the striking paradox of predicted loss-of-function mutations in TGFB2 causing enhanced TGFβ signaling in this emerging familial aortopathy., Competing Interests: The authors declare no conflict of interest.