Mouse Kidney Research Articles

Fenofibrate attenuates renal lipotoxicity in uninephrectomized mice with high-fat diet-induced obesity.

The objective of this study was to investigate the role of fenofibrate, a peroxisome proliferator-activated receptor-α agonist, in obesity-induced kidney damage (lipotoxicity) in mice with uninephrectomy. C57BL/6 mice underwent uninephrectomy and sham surgeries and were fed normocaloric or high-fat diets. After 10 weeks, obese mice were administered 0.02% fenofibrate for 10 weeks. Kidney function and morphology were evaluated, as well as levels of inflammatory and fibrotic mediators and lipid metabolism markers. High-fat diet-fed mice developed characteristic obesity and hyperlipidemia, with subsequent renal lipid accumulation and damage, including mesangial expansion, interstitial fibrosis, inflammation, and proteinuria. These changes were greater in obese uninephrectomy mice than in obese sham mice. Fenofibrate treatment prevented hyperlipidemia and glomerular lesions, lowered lipid accumulation, ameliorated renal dysfunction, and attenuated inflammation and renal fibrosis. Furthermore, fenofibrate treatment downregulated renal tissue expression of plasminogen activator inhibitor-1, monocyte chemoattractant protein-1, and local expression of fibroblast growth factor-21. Peroxisome proliferator-activated receptor-α activation by fenofibrate, with subsequent lipolysis, attenuated glomerular and tubulointerstitial lesions induced by renal lipotoxicity, thus protecting the kidneys of uninephrectomy mice from obesity-induced lesions. The study findings suggest a pathway in the pharmacological action of fenofibrate, providing insight into the mechanisms involved in kidney damage caused by obesity in kidney donors.

Novel insights into antioxidant status, gene expression, and immunohistochemistry in an animal model infected with camel-derived Trypanosoma evansi and Theileria annulata

Abstract Background Hemoprotozoan diseases, especially trypanosomosis and theileriosis, adversely affect the productivity, growth, and performance of camels. Regular sampling and investigation of camels are challenging due to several factors. Consequently, there is a lack of knowledge on camel parasite genotyping, cytokine production, and oxidative stress parameters during infection. Methods The present study investigated two critical blood protozoa infecting camels in Egypt, Trypanosoma evansi and Theileria annulata, using molecular methods, specifically 18S rRNA gene analysis. Following molecular confirmation, experimental infections were induced in Swiss albino mice to assess the expression of immune response genes and oxidative stress parameters. The study further explored the correlation between histopathological alterations and inflammatory reactions in the kidney, spleen, and liver of infected mice, alongside the immunohistochemical expression of caspase-3, proliferating cell nuclear antigen (PCNA), and tumor necrosis factor (TNF). Results Trypanosoma evansi and T. annulata isolated from naturally infected camels were molecularly identified and deposited in GenBank under accession numbers OR116429 and OR103130, respectively. Infection with T. evansi and T. annulata caused significant adverse effects on the immune condition of infected mice, increasing the pathogenicity of the infection. This was evidenced by a significant increase in oxidative stress parameter levels in both naturally infected camels and experimentally infected mice compared to healthy controls. Furthermore, the expression of immune response genes was significantly elevated in infected mice. Immunohistochemistry analysis showed a pronounced upregulation of caspase-3, PCNA, and TNF in the infected groups relative to the control group. These findings are the first to be reported in Egypt. Conclusions This study successfully identified and genotyped two economically important blood protozoa, T. evansi and T. annulata, from camels in Egypt. Additionally, the experimental animal model provided valuable insights into the immune response, oxidative stress, and histopathological changes induced by these parasites, demonstrating comparable results to naturally infected camels. These findings highlight the potential of this model to study parasite–host interactions and immune responses, contributing to a better understanding of the pathogenic mechanisms of T. evansi and T. annulata infections. This model may be useful for future studies focused on disease control and therapeutic interventions. Graphical Abstract

Deficiency of lysophosphatidic acid receptor 3 decreases erythropoietin production in hypoxic mouse kidneys

Deficiency of lysophosphatidic acid receptor 3 decreases erythropoietin production in hypoxic mouse kidneys

Hypoxia and collagen deposition in the kidneys infected with Acanthamoeba sp.

Acanthamoeba spp. are facultative, opportunistic pathogens that are found in diverse environments. In the hosts, they lead to multi-organ disease. Recent studies reported that they may induce changes in the kidneys of hosts. The aim of the study was to determine the influence of Acanthamoeba sp. on hypoxia and collagen deposition in the kidneys of immunocompetent and immunosuppressed mice infected with Acanthamoeba sp. The results strongly suggest that Acanthamoeba sp. induces hypoxia in mice with normal and reduced immune response by increasing gene and/or protein expression of HIF1α as well as HIF2α. Additionally, the activation of these factors is probably induced via NOX2/ROS. Hypoxia promotes vessel formation, and we found that angiogenesis occurs in the kidneys of mice infected with the parasite regardless of their immunological status. The proangiogenic factors released in hypoxic conditions cause modulation and inflammation in the kidney cells, which in turn leads to collagen deposition via TGF-β. This work reveals mechanisms occurring in the hosts infected with Acanthamoeba sp., highlights as well as supports the relevance of pathophysiology in the kidneys in hosts with systematic acanthamoebiasis.

αKlotho modulates BNIP3-mediated mitophagy by regulating FoxO3 to decrease mitochondrial ROS and apoptosis in contrast-induced acute kidney injury.

Contrast-induced acute kidney injury (CI-AKI) is one of the main causes of hospital-acquired renal failure, and still lacks of effective treatments. Previously, we demonstrated that αKlotho, which is an anti-aging protein that highly expresses in the kidney, has therapeutic activity in CI-AKI through promoting autophagy. However, the specific mechanism underlying αKlotho-mediated autophagy remains unclear. The RNA sequencing analysis of renal cortex revealed that the differentially expressed genes related to autophagy between αKlotho-treated CI-AKI mice and vehicle-treated CI-AKI mice were found to be associated with mitophagy and apoptosis. In the kidney of CI-AKI mice and HK-2 cells exposed to Iohexol, we revealed that αKlotho promoted mitophagy and decreased cell apoptosis. Mechanistically, αKlotho attenuated mitochondria damage, decreased mitochondrial ROS by upregulating BNIP3-mediated mitophagy. BNIP3 deletion abolished the beneficial effects of αKlotho both in vivo and in vitro. Moreover, we further demonstrated that αKlotho upregulated FoxO3 nuclear expression in Iohexol-treated HK-2 cells. Knockdown of FOXO3 gene inhibited αKlotho-promoted BNIP3-mediated mitophagy and subsequently increased the oxidative injury and cell apoptosis. Taken together, our results indicated a critical role of αKlotho in alleviating CI-AKI via mitophagy promotion involving the FoxO3-BNIP3 pathway.

Macrophage-Specific Lactate Dehydrogenase Expression Modulates Inflammatory Function In Vitro.

In acute kidney injury, macrophages play a major role in regulating inflammation. Classically activated macrophages (M1) undergo drastic metabolic reprogramming during their differentiation and upregulate the aerobic glycolysis pathway to fulfill their pro-inflammatory functions. NAD+ regeneration is crucial for the maintenance of glycolysis and the most direct pathway by which this occurs is via the fermentation of pyruvate to lactate, catalyzed by lactate dehydrogenase A (LDHA). Our previous study determined that LDHA is predominantly expressed in the proximal segments of the nephron in the mouse kidney and increases with hypoxia. This study investigates the potential of LDHA as a therapeutic target for inflammation by exploring its role in macrophage function in vitro. Bone-marrow-derived macrophages (BMDMs) were isolated from myeloid-specific LDHA knockout mice derived from crossbreeding LysM-Cre transgenic mice and LDHA floxed mice. RNA sequencing and LC-MS/MS metabolomics analyses were used in this study to determine the effect of LDHA deletion on BMDM following stimulation with IFN-γ. LDHA deletion in IFN-γ BMDMs resulted in a significant alteration of the macrophage activation and functional pathways, and change in glycolytic, cytokine, and chemokine gene expression. Metabolite concentrations associated with pro-inflammatory macrophage profiles were diminished while anti-inflammatory-associated ones were increased in LDHA KO BMDMs. Glutamate and amino sugars metabolic pathways were significantly affected by the LDHA deletion. A combined muti-omics analysis highlighted changes in Rap1 signaling, cytokine-cytokine receptor interaction, focal adhesion, and MAPK signaling metabolism pathways. Deletion of LDHA in macrophages results in a notable reduction in the pro-inflammatory profile and concurrent upregulation of anti-inflammatory pathways. These findings suggest that LDHA could serve as a promising therapeutic target for inflammation, a key contributor to the pathogenesis of acute kidney injury.

Carnosol alleviates cisplatin-induced acute kidney injury by regulating apoptosis and pyroptosis.

The use of the common anticancer drug cisplatin (CP) in clinical practice often leads to acute kidney injury (AKI); however, no protective therapy is available. Therefore, new drugs that reduce the nephrotoxicity induced by CP are urgently needed. Carnosol (CA) is an antioxidant found. We investigated the renoprotective effects of CA on CP-induced AKI in male C57BL/6 mice and HK2 cells. CA mitigated renal dysfunction, histopathological changes and tubular injury in vivo, as indicated by the expression of NGAL, KIM1 and HMGB1. Moreover, the numbers of apoptotic cells and the expression of apoptotic proteins were dramatically reduced after CA treatment in mouse kidneys and HK2 cells. CA significantly ameliorated CP-induced inflammation and decreased TNF-α and IL-1β levels in vivo and in vitro and macrophage infiltration in the mouse kidney. CA decreased the expression levels of p-p65/p65, NLRP3 and ASC, which indicates that CA suppressed the activation of the NF-κB/NLRP3 signaling axis induced by CP in vivo and in vitro. In addition, CA decreased the levels of certain protein in pyroptotic cells, as indicated by the expression of cleaved caspase-1, GSDMD, and mature IL-1β and IL-18 in vivo and in vitro. Finally, CA reduced the level of cleaved caspase-1, but those of GSDMD and NLRP3 protein were not significantly different after treatment with the NLRP3 inhibitor MCC950 and were elevated by the NLRP3 activator nigericin. In conclusion, this study revealed that CA protects against CP-induced AKI by decreasing apoptosis and NF-κB/NLRP3/GSDMD-mediated pyroptosis, which provides new insight into the prevention of AKI.

New Therapeutic Method for Alleviating Damage of Acute Kidney Injury Through BCL-2 Gene Promoter I-Motif

Acute kidney injury (AKI) is a global public health problem with its pathogenesis not fully understood. Excessive apoptosis of renal tubular epithelial cells is an important feature of AKI patients, and therefore an anti-apoptotic approach could be used in the treatment for AKI. Up-regulation of B-cell lymphoma-2 (BCL-2) gene and protein has been found to be correlated with anti-apoptosis of cells. It has been found that the presence of the C-rich sequence on the upstream region of the BCL-2 gene promoter could form DNA secondary i-motif structure, and its stabilization by small molecules could up-regulate gene transcription and translation. In the present study, we constructed AKI models through folic acid (FA) induction. With these in vitro and in vivo models, we demonstrated that the acridone derivative A22 could up-regulate the expression of BCL-2 by targeting its gene promoter i-motif to reduce renal tubular epithelial cell apoptosis and improve renal function in many ways. A22 could alleviate FA-induced oxidative stress injury, inflammatory response, and endoplasmic reticulum stress in mouse kidneys. Our results provided a potentially new anti-apoptotic approach for the treatment of early stages of AKI. Our employed model focused on its short-term effect on AKI, while its long-term efficacy and safety, particularly regarding the regeneration of renal tubular epithelial cells, require further investigation before clinical application. This study further demonstrated that promoter i-motif could be targeted for up-regulating BCL-2 expression for the treatment of important diseases caused by excessive apoptosis.

KLF13 promotes SLE pathogenesis by modifying chromatin accessibility of key proinflammatory cytokine genes

Although significant progress has been achieved in elucidating the genetic architecture of systemic lupus erythematosus (SLE), identifying genes underlying the pathogenesis has been challenging. The NZM2410-derived lupus susceptibility Sle3 locus is associated with T cell hyperactivity and activated myeloid cells. However, candidate genes associated with these phenotypes have not been identified. Here, we narrow the Sle3 locus to a smaller genomic segment (Sle3k) and show that mice carrying Sle3k and Sle1 loci developed lupus nephritis. We identify Klf13 as the primary candidate gene that is associated with genome-wide transcription changes resulting in higher levels of proinflammatory cytokines, enhanced T cell activation, and hyperresponsiveness of myeloid cells. Correspondingly, Klf13–/– mice display repression of genes involved in mediating immune activation, including key proinflammatory cytokines/chemokines in T cells and dysregulation in cytokine signaling pathways in myeloid cells in response to toll receptor ligands. Klf13 upregulation is associated with increased production of RANTES, a key chemokine in lupus nephritis, in activated T cells and the kidneys of lupus-prone mice. In sum, our findings reveal Klf13 as a key gene in the Sle3 interval in mediating lupus pathogenesis that may have implications in the rational design of new therapies for SLE.

Bilirubin-Modified Chondroitin Sulfate-Mediated Multifunctional Liposomes Ameliorate Acute Kidney Injury by Inducing Mitophagy and Regulating Macrophage Polarization.

Acute kidney injury (AKI) is a dynamic process associated with inflammation, oxidative stress, and lipid peroxidation, in which mitochondrial mitophagy and macrophage polarization play a critical role in the pathophysiology. Based on the expression of the CD44 receptor on renal tubular epithelial cells (RTECs) and activated M1 macrophages being abnormally increased, accompanied by up-regulation of reactive oxygen species (ROS) during AKI, the conjugates of bilirubin (BR), an endogenous antioxidant which has the property of anti-inflammation, and chondroitin sulfate (CS) with CD44-targeting property could be a promising therapeutic carrier. In this study, we develop a CD44-targeted/ROS-responsive CS-BR-mediated multifunctional liposome loading celastrol (CS-BR@CLT) for the targeted therapy of AKI. CS-BR@CLT is shown to selectively accumulate in AKI mouse kidneys via targeting of CD44 receptors. Treatment with CS-BR@CLT significantly ameliorates acute kidney injury caused by ischemia-reperfusion and protects renal function. Mechanistically, CS-BR@CLT inhibits apoptosis, protects mitochondria, promotes autophagy, regulates macrophage polarization, and alleviates interstitial inflammation. Overall, our study demonstrates that CS-BR@CLT could be a promising strategy to ameliorate acute kidney injury.

MiR-199a-5p aggravates renal ischemia-reperfusion and transplant injury by targeting AKAP1 to disrupt mitochondrial dynamics.

Renal ischemia-reperfusion injury (IRI) is a complex pathophysiological process and a major cause of delayed graft function (DGF) after transplantation. MicroRNA (miRNA) has important roles in the pathogenesis of IRI and may represent promising therapeutic targets for mitigating renal IRI. miRNA sequencing was performed to profile microRNA expression in mouse kidneys after cold storage and transplantation (CST). Lentivirus incorporating a miR-199a-5p modulator was injected into mouse kidney in situ before syngenetic transplantation and unilateral IRI to determine the effect of miR-199a-5p in vivo. miR-199a-5p mimic or inhibitor was transfected cultured tubular cells before ATP depletion recovery treatment to examine the role of miR-199a-5p in vitro. Sequencing data and microarray showed upregulation of miR-199a-5p in mice CST and human DGF samples. Lentivirus incorporating a miR-199a-5p mimic aggravated renal IRI, and protective effects were obtained with a miR-199a-5p inhibitor. Treatment with the miR-199a-5p inhibitor ameliorated graft function loss, tubular injury, and immune response after CST. In vitro experiments revealed exacerbation of mitochondria dysfunction upon ATP depletion and repletion model in the presence of the miR-199a-5p mimic, whereas dysfunction was attenuated when the miR-199a-5p inhibitor was applied. miR-199a-5p was shown to target A-kinase anchoring protein 1 (AKAP1) by double luciferase assay and miR-199a-5p activation reduced dynamin-related protein 1 (Drp1)-s637 phosphorylation and mitochondrial length. Overexpression of AKAP1 preserved Drp1-s637 phosphorylation and reduced mitochondrial fission. miR-199a-5p activation reduced AKAP1 expression, promoted Drp1-s637 dephosphorylation, aggravated the disruption of mitochondrial dynamics, and contributed to renal IRI.NEW & NOTEWORTHY This study identifies miR-199a-5p as a key regulator in renal ischemia-reperfusion injury through microRNA sequencing in mouse models and human delayed graft function. miR-199a-5p worsens renal IRI by aggravating graft dysfunction, tubular injury, and immune response, while its inhibition shows protective effects. miR-199a-5p downregulates A-kinase anchoring protein 1 (AKAP1), reducing dynamin-related protein 1 (Drp1)-s637 phosphorylation, increasing mitochondrial fission, and causing dysfunction. Targeting the miR-199a-5p/AKAP1/Drp1 axis offers therapeutic potential for renal IRI, as AKAP1 overexpression preserves mitochondrial integrity by maintaining Drp1-s637 phosphorylation.

Walnut-derived peptides cross the blood–brain barrier and ameliorate Aβ-induced hypersynchronous neural network activity

Walnut peptides exhibit promising neuroprotective effects; however, they must be absorbed in their intact form through the gastrointestinal tract into the bloodstream and brain. In this study, the effects of the walnut peptide TWLPLPR (TW-7) were evaluated in mice, including its absorption and distribution ability to cross the blood–brain barrier, and inhibitory effects on hyperactivity of primary hippocampal neurons. TW-7 was stable in plasma, and the peptide retention rate was 88.19 ± 0.70 % after 48 h. In vitro imaging indicated that TW-7 was distributed in the brain, liver, lungs, and kidneys of mice after gavage, and an immunofluorescence analysis indicated that TW-7 could accumulate in mouse brain parenchyma; in addition, TW-7 reached its maximum concentration (5.36 ± 1.59 µg/mL) in plasma 2 h after gavage, and reached its peak concentration (0.95 ± 0.19 µg/g) in brain tissue 4 h after gavage. Microelectrode array and immunofluorescence analyses confirmed that TW-7 ameliorates the overexcitation of primary hippocampal neurons induced by Aβ25–35 through inhibiting the excessive release of glutamate and protecting synaptic structure and function. These results suggest that TW-7 can penetrate the blood–brain barrier in mice and positively affect the electrophysiological activity of neurons. More broadly, these findings provide a theoretical basis for the development and application of walnut peptide-based functional food for Alzheimer’s disease intervention.

Effect of Arabic Gum on Gentamicin Nephrotoxicity in Mice: A Pathological Study

<p><strong>Aim</strong> To investigate the effect of Arabic gum on gentamycin nephrotoxicity in mice kidney.<br /><strong>Methods</strong> Forty (40) mice were divided into five groups, eight mice in each. Group one (G1) stands for the negative control group. The second one (G2) was injected with gentamycin only, while the third one (G3) was given an Arabic gum orally 10g/kg. The 4th group (G4) was injected with gentamycin for 8 days, and then followed by Arabic gum orally for 8 days. The fifth group (G5) was injected with gentamycin plus oral administration of Arabic gum at the same time. A scoring system (+1-+4) was used to grade the histological features in the kidneys.<br /><strong>Results</strong> The results revealed a significant increase in body weight in G3 group only; this group presented a significant decrease in the level of both urea and creatinine. Group G2 showed a marked elevation in both serum urea and creatinine. Acute tubular necrosis (+4), in both G2 and G5. In G3, kidney sections presented mild cell swelling of the tubular epithelium in addition to the normal architectures (score +1), while G4 sections revealed tubular hyalin cast, expansion of glomerular tufts.<br /><strong>Conclusion</strong> The research indicates that gentamycin leads to kidney damage in mice. Arabic gum could be a treatment option although additional studies are required to determine the best dosing and timing, for optimal effectiveness.</p>

Aristolochic acid I promotes renal tubulointerstitial fibrosis by up-regulating expression of indoleamine 2,3-dioxygenase-1 (IDO1).

Aristolochic acid I (AAI) is strongly nephrotoxic and can cause "Aristolochic acid nephropathy (AAN)". Aristolochic acid nephropathy is characterized by extensive renal interstitial fibrosis. However, the exact mechanism by which it occurs has not been fully elucidated. lt has been reported that indoleamine 2,3-dioxygenase-1 (IDO1) promotes renal fibrosis in renal disorders, but it is unclear how IDO1 functions in AAI-induced kidney fibrosis. In this work, we systematically examined the role of IDO1 in AAI-induced renal tubulointerstitial fibrosis. The results showed that AAI induced upregulation of IDO1 expression in renal tubular epithelial cells and mouse kidney. Inhibition of IDO1 expression reduced the levels of fibrosis-associated markers α-SMA, COL-I and FN and ameliorated renal tubular epithelial cell fibrosis. It also improved renal function, reduced collagen deposition, and ameliorated interstitial fibrosis in mice. Moreover, we discovered that inhibition of IDO1 decreased the expression of the apoptotic protein BAX, raised the expression of BCL-2 protein, and reduced apoptosis. The above studies suggest that IDO1 is a target of action in renal tubulointerstitial fibrosis caused by AAI, and inhibition of IDO1 may be a viable approach for the therapy of AAI-induced renal tubulointerstitial fibrosis.

Progressive amyloid-β accumulation in the brain leads to altered protein expressions in the liver and kidneys of APP knock-in mice

Impaired hepatic and renal function influence Alzheimer's disease (AD) progression; however, whether AD progression affects these important organ functions remains unclear. Here, we investigated the impact of AD progression, characterized by brain amyloid-beta (Aβ) accumulation, on liver and kidney function of AppNL-G-F/NL-G-F (APP-KI) mice using quantitative proteomics. SWATH-based quantitative proteomics revealed changes in mitochondrial, drug metabolism, and pharmacokinetic-related proteins in mouse liver and kidneys during the early (2-month-old) and intermediate (5-month-old) stages of Aβ accumulation. Notably, in 5-month-old APP-KI mouse liver, 25 phase I/II metabolizing enzymes (8 CYPs, 7 UGTs, 7 CESs, and 3 SLCs) and five transporters (2 ABCs and 3 SLCs) were significantly altered; specifically, Ugt1a9 and Slc33a1 protein abundances increased, whereas Ugt1a1 and Abcc3 protein abundances decreased. In the kidneys, 13 phase I/II metabolizing enzymes and 10 ABC-SLC transporters were altered, including Ugt1a6, Ugt1a7, Slc22a7, and Abcb1a. Additionally, plasma proteins, such as albumin and alpha-1-acid glycoprotein, which are critical for drug binding and distribution, were also altered. These results underscore the significant role of progressive brain Aβ accumulation in modifying hepatic and renal protein abundances, potentially influencing drug metabolism and disposition in AD. Our findings provide novel insights into the complex relationship between AD progression and organ dysfunction.

GSDMD Mediates Ang II-Induced Hypertensive Nephropathy by Regulating the GATA2/AQP4 Signaling Pathway.

Hypertensive nephropathy is a common complication of hypertension. However, no effective measures are currently available to prevent the progression of renal insufficiency. Gasdermin D (GSDMD) is a crucial mediator of pyroptosis that induces an excessive inflammatory response. In the present study, we aimed to determine the effect of GSDMD on the pathogenesis of hypertensive nephropathy, which may provide new insights into the treatment of hypertensive nephropathy. C57BL/6 (wild-type, WT) and Gsdmd knockout (Gsdmd-/-) mice were subcutaneously infused with angiotensin II (Ang II) via osmotic mini-pumps to establish a hypertensive renal injury model. Recombinant adeno-associated virus serotype 9 (AAV9) carrying GSDMD cDNA was used to overexpress GSDMD. Renal function biomarkers, histopathological changes, and inflammation and fibrosis indices were assessed. Transcriptome sequencing (RNA-seq) and cleavage under targets and mentation (CUT & Tag) experiments were performed to identify the downstream pathogenic mechanisms of GSDMD in hypertensive nephropathy. GSDMD was activated in the kidneys of mice induced by Ang II (P < 0.001). This activation was primarily observed in the renal tubular epithelial cells (P < 0.0001). GSDMD deficiency attenuated renal injury and fibrosis induced by Ang II (P < 0.0001), whereas Gsdmd overexpression promoted renal injury and fibrosis (P < 0.01). Mechanistically, GSDMD increased Ang II-induced GATA binding protein 2 (GATA2) transcription factor expression (P < 0.01). GATA2 also bound to the aquaporin 4 (Aqp4) promoter sequence and facilitated Aqp4 transcription (P < 0.001), leading to renal injury and fibrosis. Moreover, treatment with GI-Y1, an inhibitor of GSDMD, alleviated Ang II-induced renal injury and fibrosis (P < 0.01). GSDMD plays an important role in the development of hypertensive nephropathy. Targeting GSDMD may be a therapeutic strategy for the treatment of hypertensive nephropathy.

GLIS3: a novel transcriptional regulator of mitochondrial functions and metabolic reprogramming in postnatal kidney and polycystic kidney disease

Background and aimsDeficiency in the transcription factor (TF) GLI-Similar 3 (GLIS3) in humans and mice leads to the development of polycystic kidney disease (PKD). In this study, we investigate the role of GLIS3 in the regulation of energy metabolism and mitochondrial functions in relation to its role in normal kidney and metabolic reprogramming in PKD pathogenesis. Approach and resultsTranscriptomics, cistromics, and metabolomics were used to obtain insights into the role of GLIS3 in the regulation of energy homeostasis and mitochondrial metabolism in normal kidney and PKD pathogenesis using GLIS3-deficient mice. Transcriptome analysis showed that many genes critical for mitochondrial biogenesis, oxidative phosphorylation (OXPHOS), fatty acid oxidation (FAO), and the tricarboxylic acid (TCA) cycle, including Tfam, Tfb1m, Tfb2m, Ppargc1a, Ppargc1b, Atp5j2, Hadha, and Sdha, are significantly suppressed in kidneys from both ubiquitous and tissue-specific Glis3-deficient mice. ChIP-Seq analysis demonstrated that GLIS3 is associated with the regulatory region of many of these genes, indicating that their transcription is directly regulated by GLIS3. Cistrome analyses revealed that GLIS3 binding loci frequently located near those of hepatocyte nuclear factor 1-Beta (HNF1B) and nuclear respiratory factor 1 (NRF1) suggesting GLIS3 regulates transcription of many metabolic and mitochondrial function-related genes in coordination with these TFs. Seahorse analysis and untargeted metabolomics corroborated that mitochondrial OXPHOS utilization is suppressed in GLIS3-deficient kidneys and showed that key metabolites in glycolysis, TCA cycle, and glutamine pathways were altered indicating increased reliance on aerobic glycolysis and glutamine anaplerosis. These features of metabolic reprogramming may contribute to a bioenergetic environment that supports renal cyst formation and progression in Glis3-deficient mice kidneys. ConclusionsWe identify GLIS3 as a novel positive regulator of the transition from aerobic glycolysis to OXPHOS in normal early postnatal kidney development by directly regulating the transcription of mitochondrial metabolic genes. Loss of GLIS3 induces several features of renal cell metabolic reprogramming. Our study identifies GLIS3 as a new participant in an interconnected transcription regulatory network, that includes HNF1B and NRF1, critical in the regulation of mitochondrial-related gene expression and energy metabolism in normal postnatal kidneys and PKD pathogenesis in Glis3-deficient mice.

Consensus tissue domain detection in spatial omics data using multiplex image labeling with regional morphology (MILWRM).

Spatially resolved molecular assays provide high dimensional genetic, transcriptomic, proteomic, and epigenetic information in situ and at various resolutions. Pairing these data across modalities with histological features enables powerful studies of tissue pathology in the context of an intact microenvironment and tissue structure. Increasing dimensions across molecular analytes and samples require new data science approaches to functionally annotate spatially resolved molecular data. A specific challenge is data-driven cross-sample domain detection that allows for analysis within and between consensus tissue compartments across high volumes of multiplex datasets stemming from tissue atlasing efforts. Here, we present MILWRM (multiplex image labeling with regional morphology)-a Python package for rapid, multi-scale tissue domain detection and annotation at the image- or spot-level. We demonstrate MILWRM's utility in identifying histologically distinct compartments in human colonic polyps, lymph nodes, mouse kidney, and mouse brain slices through spatially-informed clustering in two different spatial data modalities from different platforms. We used tissue domains detected in human colonic polyps to elucidate the molecular distinction between polyp subtypes, and explored the ability of MILWRM to identify anatomical regions of the brain tissue and their respective distinct molecular profiles.

3D-printed scaffolds with controlled-releasing compounds for ectopic activation of dormant ovarian follicles

Throughout a woman&amp;rsquo;s reproductive life, hundreds of functioning follicles are activated for development, while thousands of dormant follicles remain in the ovaries. Dormant follicle activation in vitro is an effective clinical strategy for women with fertility needs who suffer from ovarian dysfunction. However, activating dormant follicles in vivo is still a challenge due to difficulties such as delivering stimulators to local sites. Here, we developed a compound-preloaded microporous scaffold by combining three-dimensional (3D) printing techniques with pharmacological activators to support and stimulate the activation and development of primordial follicles. The gelatin/alginate composite scaffolds exhibited exceptional mechanical properties and biological compatibility, effectively supporting the survival of ovarian granulosa cells for more than 7 days, which is essential for oocyte development. Furthermore, the ovarian tissue-scaffold complex successfully survived after transplantation under the mouse kidney capsule, demonstrating its excellent biocompatibility. After pre-mixing widely used clinical activators into the bio-ink, the scaffold had the ability to gradually release the mixture of compounds, effectively activating primordial follicles. By transplanting the ovary-scaffold complex containing activators into the mouse abdominal subcutaneous pocket, dormant follicles could be activated subcutaneously and developed into growing follicles. The number of growing follicles is approximately three times higher compared to the group without activators. In conclusion, by integrating biomaterials, activators, and 3D printing technology, we have developed 3D-printed biological scaffolds that can ectopically support primordial follicle activation and development in vivo. This novel approach could provide a promising strategy for treating ovarian insufficiency and endocrine disorders in the clinic, without the need for in situ ovarian tissue grafting.

Anti-inflammatory effects of para-quinone methide derivatives on ulcerative colitis.

A series of para-quinone methide derivatives were evaluated their anti-inflammatory activity. Through the screening of the lipopolysaccharide (LPS)-induced inflammatory cell model in Raw264.7 cells, it was found that the inhibitory activity of meta-substituted derivatives on NO production was superior to that of ortho- and para-substituted derivatives. Among them, in the inflammatory cell model, the meta-trifluoromethyl substituted para-quinone methide derivative 1i had the best activity in inhibiting LPS-induced excess generation of NO. And 1i could effectively inhibit the increase of ROS in inflammatory cells, the expression of iNOS related to the production of NO, and the expressions of inflammation related initiating protein TLR4, pro-inflammatory cytokines IL-6 and TNF-α, inflammasome NLRP3 and Caspase1. In the dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mouse model, the active derivative 1i could inhibit DSS-induced colon shortening, and reverse DSS-induced pathological changes in colon tissue, such as inflammatory infiltration, structural destruction and crypt disappearance. 1i could effectively inhibit oxidative stress, inflammation and apoptosis in UC mice. Moreover, through the determination of serum biochemical indicators, tissue pathologies and tissue organ indexes, 1i could effectively reverse the damage to mouse liver and kidney caused by DSS, playing a protective role in liver and kidney of mice. In summary, 1i was an effective anti-inflammatory reagent and could be developed as a potential drug for anti-UC.