Treatment with quercetin inhibits SARS-CoV-2 N protein-induced acute kidney injury by blocking Smad3-dependent G1 cell-cycle arrest

Self-Assembled Pt/Honokiol Nanomicelles for the Treatment of Sepsis-Associated Acute Kidney Injury

Sepsis is a severe and complex systemic infection that can result in multiple organ dysfunction. Sepsis-associated acute kidney injury (SAKI), caused by inflammatory response, oxidative stress, and cellular apoptosis, is a common complication that seriously impacts patient survival rates. Herein, a potent and novel metal-polyphenol nanomicelle can be efficiently self-assembled with Pt4+ and honokiol (HK) by the chelation, π-π conjugation, hydrophobic action, and the surfactant properties of Tween-80. These nanomicelles not only enhance drug bioavailability (encapsulation rates: Pt─49%, HK─70%) and reduce drug toxicity (safety dose: <20 μg/g) but also improve targeting toward damaged renal tissues. Furthermore, Pt4+ and HK in the nanomicelles exert a synergistic physiological effect by scavenging free radicals to alleviate oxidative damage, inhibiting macrophage activation and the release of inflammatory factors to regulate inflammation, and displaying broad-spectrum antimicrobial activity to control infection. These actions collectively protect renal tissue and restore its functionality. Here, we constructed metal-polyphenol nanomicelles (Pt/HK-NMs) via ingenious and efficient self-assembly, providing a new strategy to compensate for deficiencies in the hemodialysis and antibiotic treatment of SAKI.

Protective effect and mechanism of Xiaoyu Xiezhuo decoction on ischemia-reperfusion induced acute kidney injury based on gut-kidney crosstalk

This study aimed to explore the mechanism of Xiaoyu Xiezhuo decoction (XXD) on ischemia-reperfusion-induced acute kidney injury (IRI-AKI) using network pharmacology methods and gut microbiota analysis. A total of 1778 AKI-related targets were obtained, including 140 targets possibly regulated by AKI in XXD, indicating that the core targets were mainly enriched in inflammatory-related pathways, such as the IL-17 signaling pathway and TNF signaling pathway. The unilateral IRI-AKI animal model was established and randomly divided into four groups: the sham group, the AKI group, the sham + XXD group, and the AKI + XXD group. Compared with the rats in the AKI group, XXD improved not only renal function, urinary enzymes, and biomarkers of renal damage such as Kim-1, cystatin C, and serum inflammatory factors such as IL-17, TNF-α, IL-6, and IL 1-β, but also intestinal metabolites including lipopolysaccharides, d-lactic acid, indoxyl sulfate, p-cresyl sulfate, and short-chain fatty acids. XXD ameliorated renal and colonic pathological injury as well as inflammation and chemokine gene abundance, such as IL-17, TNF-α, IL-6, IL-1β, ICAM-1, and MCP-1, in AKI rats via the TLR4/NF-κB/NLRP3 pathway, reducing the AKI score, renal pathological damage, and improving the intestinal mucosa's inflammatory infiltration. It also repaired markers of the mucosal barrier, including claudin-1, occludin, and ZO-1. Compared with the rats in the AKI group, the α diversity was significantly increased, and the Chao1 index was significantly enhanced after XXD treatment in both the sham group and the AKI group. The treatment group significantly reversed this change in microbiota.

Research on the global trends of COVID-19 associated acute kidney injury: a bibliometric analysis

Critically ill COVID-19 patients may exhibit various clinical symptoms of renal dysfunction including severe Acute Kidney Injury (AKI). Currently, there is a lack of bibliometric analyses on COVID-19-related AKI. The aim of this study is to provide an overview of the current research status and hot topics regarding COVID-19 AKI. The literature was retrieved from the Web of Science Core Collection (WoSCC) database. Subsequently, we utilized Microsoft Excel, VOSviewer, Citespace, and Pajek software to revealed the current research status, emerging topics, and developmental trends pertaining to COVID-19 AKI. This study encompassed a total of 1507 studies on COVID-19 AKI. The United States, China, and Italy emerged as the leading three countries in terms of publication numbers, contributing 498 (33.05%), 229 (15.20%), and 140 (9.29%) studies, respectively. The three most active and influential institutions include Huazhong University of Science and Technology, Wuhan University and Harvard Medical School. Ronco C from Italy, holds the record for the highest number of publications, with a total of 15 papers authored. Cheng YC's work from China has garnered the highest number of citations, totaling 470 citations. The co-occurrence analysis of author keywords reveals that 'mortality', 'intensive care units', 'chronic kidney disease', 'nephrology', 'renal transplantation', 'acute respiratory distress syndrome', and 'risk factors' emerge as the primary areas of focus within the realm of COVID-19 AKI. In summary, this study analyzes the research trends in the field of COVID-19 AKI, providing a reference for further exploration and research on COVID-19 AKI mechanisms and treatment.

Biochanin A suppresses Klf6-mediated Smad3 transcription to attenuate renal fibrosis in UUO mice

BACKGROUND

Renal fibrosis is a hallmark of chronic kidney disease (CKD). Smad3 serves as the principal transcription factor mediating the pro-fibrosis effects of TGF-β signaling in renal fibrosis. Biochanin A (BCA), a natural isoflavone, has been shown to attenuate renal fibrosis by inhibiting TGF-β signaling but the detailed mechanisms remain unresolved. This study aimed to elucidate the specific mechanisms by which BCA modulates TGF-β signaling.

METHODS

Renal fibrosis models were established both in vitro, using TGF-β1-stimulated mouse renal tubular TCMK1 cells, and in vivo, employing mice with unilateral ureter obstruction (UUO). RNA-seq was conducted to identify BCA-regulated genes. The AnimalTFDB4.0 database was utilized to predict transcription factors with potential binding to Smad3 promoter. The activities of TGF-β signaling and the cloned mouse Smad3 promoter were assessed using luciferase reporter assays. Plasmid transfection was performed using polyethylenimine in TCMK1 cells or ultrasound microbubbles in UUO kidneys. Gene expression was analyzed by RT-PCR, western blot, and immunohistochemistry assays.

RESULTS

BCA significantly inhibited TGF-β signaling activity and suppressed TGF-β1-induced fibrotic gene expression in TCMK1 cells. RNA-seq and in silico analyses identified Smad3 as the key gene downregulated by BCA, while leaving Smad2 unaffected. This selective transcriptional suppression of Smad3 by BCA was validated by luciferase reporter assays using the cloned Smad3 promoter. Furthermore, transcription factor binding prediction identified that Klf6, a transcription factor downregulated by BCA, has binding potential to the Smad3 promoter and promotes Smad3 transcription. Klf6 expression was induced in TGF-β1-stimulated TCMK1 cells and UUO kidneys, but this induction was abolished upon BCA treatment. Importantly, Klf6 overexpression restored Smad3 expression and counteracted the anti-fibrosis effects of BCA in both TGF-β1-stimulated TCMK1 cells and UUO kidneys.

CONCLUSION

TGF-β-responsive Klf6 transcriptionally transactivates Smad3 expression. BCA exerts anti-renal fibrosis effects by inhibiting the Klf6-Smad3 signaling axis, underscoring its therapeutic potential in the treatment of CKD.

SARS-CoV-2 ORF3a induces COVID-19-associated kidney injury through HMGB1-mediated cytokine production

The primary challenge posed by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is COVID-19-related mortality, often exacerbated by additional medical complications, such as COVID-19-associated kidney injuries (CAKIs). Up to half of COVID-19 patients experience kidney complications, with those facing acute respiratory failure and kidney injury having the worst overall prognosis. Despite the significant impact of CAKI on COVID-19-related mortality and its enduring effects in long COVID, the underlying causes and molecular mechanisms of CAKI remain elusive. In this study, we identified a functional relationship between the expression of the SARS-CoV-2 ORF3a protein and inflammation-driven apoptotic death of renal tubular epithelial cells in patients with CAKI. We demonstrate in vitro that ORF3a independently induces renal cell-specific apoptotic cell death, as evidenced by the elevation of kidney injury molecule-1 (KIM-1) and the activation of NF-kB-mediated proinflammatory cytokine (TNFα and IL-6) production. By examining kidney tissues of SARS-CoV-2-infected K18-ACE2 transgenic mice, we observed a similar correlation between ORF3a-induced cytopathic changes and kidney injury. This correlation was further validated through reconstitution of the ORF3a effects via direct adenoviral injection into mouse kidneys. Through medicinal analysis, we identified a natural compound, glycyrrhizin (GL4419), which not only blocks viral replication in renal cells, but also mitigates ORF3a-induced renal cell death by inhibiting activation of a high mobility group box 1 (HMGB1) protein, leading to a reduction of KIM-1. Moreover, ORF3a interacts with HMGB1. Overproduction or downregulation of hmgb1 expression results in correlative changes in renal cellular KIM-1 response and respective cytokine production, implicating a crucial role of HMGB1 in ORF3a-inflicted kidney injuries. Our data suggest a direct functional link between ORF3a and kidney injury, highlighting ORF3a as a unique therapeutic target contributing to CAKI.

IMPORTANCE

The major challenge of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection during the pandemic is COVID-19-related mortality, which has tragically claimed millions of lives. COVID-19-associated morbidity and mortality are often exacerbated by pre-existing medical conditions, such as chronic kidney diseases (CKDs), or the development of acute kidney injury (AKI) due to COVID-19, collectively known as COVID-19-associated kidney injuries (CAKIs). Patients who experience acute respiratory failure with CAKI have the poorest clinical outcomes, including increased mortality. Despite these alarming clinical findings, there is a critical gap in our understanding of the underlying causes of CAKI. Our study establishes a direct correlation between the expression of the SARS-CoV-2 viral ORF3a protein and kidney injury induced by ORF3a linking to CAKI. This functional relationship was initially observed in our clinical studies of COVID-19 patients with AKI and was further validated through animal and in vitro cellular studies, either by expressing ORF3a alone or in the context of viral infection. By elucidating this functional relationship and its underlying mechanistic pathways, our research deepens the understanding of COVID-19-associated kidney diseases and presents potential therapeutic avenues to address the healthcare challenges faced by individuals with underlying conditions.

The Role of Dental-derived Stem Cell-based Therapy and Their Derived Extracellular Vesicles in Post-COVID-19 Syndrome-induced Tissue Damage

Long coronavirus disease 2019 (COVID-19) is linked to an increased risk of post-acute sequelae affecting the pulmonary and extrapulmonary organ systems. Up to 20% of COVID-19 patients may proceed to a more serious form, such as severe pneumonia, acute respiratory distress syndrome (ARDS), or pulmonary fibrosis. Still, the majority of patients may only have mild, self-limiting sickness. Of particular concern is the possibility of parenchymal fibrosis and lung dysfunction in long-term COVID-19 patients. Furthermore, it has been observed that up to 43% of individuals hospitalized with COVID-19 also had acute renal injury (AKI). Care for kidney, brain, lung, cardiovascular, liver, ocular, and tissue injuries should be included in post-acute COVID-19 treatment. As a powerful immunomodulatory tool in regenerative medicine, dental stem cells (DSCs) have drawn much interest. Numerous immune cells and cytokines are involved in the excessive inflammatory response, which also has a significant effect on tissue regeneration. A unique reservoir of stem cells (SCs) for treating acute lung injury (ALI), liver damage, neurological diseases, cardiovascular issues, and renal damage may be found in tooth tissue, according to much research. Moreover, a growing corpus of in vivo research is connecting DSC-derived extracellular vesicles (DSC-EVs), which are essential paracrine effectors, to the beneficial effects of DSCs. DSC-EVs, which contain bioactive components and therapeutic potential in certain disorders, have been shown as potentially effective therapies for tissue damage after COVID-19. Consequently, we explore the properties of DSCs in this work. Next, we'll look at how SARS-CoV-2 affects tissue damage. Lastly, we have looked at the use of DSCs and DSC-EVs in managing COVID-19 and chronic tissue damage, such as injury to the heart, brain, lung, and other tissues.

Renal implications of coronavirus disease 2019: insights into viral tropism and clinical outcomes

In recent years, multiple coronaviruses have emerged, with the latest one, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing a global pandemic. Besides respiratory symptoms, some patients experienced extrapulmonary effects, such as cardiac damage or renal injury, indicating the broad tropism of SARS-CoV-2. The ability of the virus to effectively invade the renal cellular environment can eventually cause tissue-specific damage and disease. Indeed, patients with severe coronavirus disease 2019 exhibited a variety of symptoms such as acute proximal tubular injury, ischemic collapse, and severe acute tubular necrosis resulting in irreversible kidney failure. This review summarizes the current knowledge on how it is believed that SARS-CoV-2 influences the renal environment and induces kidney disease, as well as current therapy approaches.

A bimetallic nanozyme coordinated with quercetin for efficient radical scavenging and treatment of acute kidney injury

Acute kidney injury (AKI), characterized by tissue inflammation and oxidative damage, is a common and potentially life-threatening complication in patients. Quercetin, a natural antioxidant, possesses diverse pharmacological properties. However, limited stability and bioavailability hinder its clinical utilization. Moreover, the application of nanotechnology in antioxidant strategies for AKI treatment faces significant knowledge gaps. These gaps stem from limited understanding of the therapeutic mechanisms and renal clearance pathways. To tackle these issues, this study aims to develop an anti-oxidation nanozyme through the coordination of quercetin (Que) with a ruthenium (Ru) doped platinum (Pt) nanozyme (RuPt nanozyme). Compared to using Que or the RuPt nanozyme alone, the combined use of Que and the nanozyme led to enhanced antioxidant activities, especially in ABTS and DPPH free radical scavenging activities. Moreover, the modified nanozyme showed remarkable efficacy in scavenging reactive oxygen species and inhibiting apoptosis in a H2O2-induced cellular model. Additionally, the in vivo study showed that the coordination-modified nanozyme effectively alleviated glycerol- and cisplatin-induced AKI by inhibiting oxidative stress. Furthermore, this nanozyme exhibited superior therapeutic efficacy when compared to free quercetin and the RuPt nanozyme. In conclusion, the findings of our study suggest that the quercetin modified RuPt nanozyme (QCN) exhibits remarkable biocompatibility and holds significant promise for the therapeutic management of AKI.

Quercetin alleviates zearalenone-induced apoptosis and necroptosis of porcine renal epithelial cells by inhibiting CaSR/CaMKII signaling pathway

Zearalenone (ZEA) is a mycotoxin that is highly contaminated in feed and can cause severe toxic effects on the kidneys and other organs of animals. Quercetin (QUE) is a plant-derived flavonoid with a variety of detoxification properties, but the mechanism by which QUE detoxifies the toxic effects induced by ZEA has not yet been fully elucidated. We treated porcine kidney cells (PK15) with 80 μM ZEA and/or 30 μM QUE. The results showed that ROS and MDA levels were increased, antioxidant system levels were down-regulated, anti-apoptotic factor expression levels were decreased, and apoptotic and necroptosis-related factors were up-regulated after ZAE exposure. In addition, the results of Ca2+ staining, mitochondrial membrane potential, and mitochondrial dynamics-related indicators showed that ZEA induced Ca2+ overload in PK15 cells and increased mitochondrial Ca2+ uptake (MCU expression increased). The accumulated ROS and free Ca2+ further aggravate mitochondrial damage and eventually lead to mitochondrial pathway apoptosis and necroptosis. Nevertheless, QUE targets CaSR to inhibit the CaSR/CaMKII pathway and regulate calcium homeostasis, thereby alleviating apoptosis and necroptosis mediated by mitochondrial dynamic disorder and dysfunction. The present study demonstrated the mechanism by which ZEA induces apoptosis and necroptosis in PK15 and the protective role of QUE in this process.

SARS-CoV-2 N protein induced acute kidney injury in diabetic db/db mice is associated with a Mincle-dependent M1 macrophage activation

"Cytokine storm" is common in critically ill COVID-19 patients, however, mechanisms remain largely unknown. Here, we reported that overexpression of SARS-CoV-2 N protein in diabetic db/db mice significantly increased tubular death and the release of HMGB1, one of the damage-associated molecular patterns (DAMPs), to trigger M1 proinflammatory macrophage activation and production of IL-6, TNF-α, and MCP-1 via a Mincle-Syk/NF-κB-dependent mechanism. This was further confirmed in vitro that overexpression of SARS-CoV-2 N protein caused the release of HMGB1 from injured tubular cells under high AGE conditions, which resulted in M1 macrophage activation and production of proinflammatory cytokines via a Mincle-Syk/NF-κB-dependent mechanism. This was further evidenced by specifically silencing macrophage Mincle to block HMGB1-induced M1 macrophage activation and production of IL-6, TNF-α, and MCP-1 in vitro. Importantly, we also uncovered that treatment with quercetin largely improved SARS-CoV-2 N protein-induced AKI in db/db mice. Mechanistically, we found that quercetin treatment significantly inhibited the release of a DAMP molecule HMGB1 and inactivated M1 pro-inflammatory macrophage while promoting reparative M2 macrophage responses by suppressing Mincle-Syk/NF-κB signaling in vivo and in vitro. In conclusion, SARS-CoV-2 N protein-induced AKI in db/db mice is associated with Mincle-dependent M1 macrophage activation. Inhibition of this pathway may be a mechanism through which quercetin inhibits COVID-19-associated AKI.

SARS-CoV-2 and the DNA damage response

The recent coronavirus disease 2019 (COVID-19) pandemic was caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 is characterized by respiratory distress, multiorgan dysfunction and, in some cases, death. The virus is also responsible for post-COVID-19 condition (commonly referred to as 'long COVID'). SARS-CoV-2 is a single-stranded, positive-sense RNA virus with a genome of approximately 30 kb, which encodes 26 proteins. It has been reported to affect multiple pathways in infected cells, resulting, in many cases, in the induction of a 'cytokine storm' and cellular senescence. Perhaps because it is an RNA virus, replicating largely in the cytoplasm, the effect of SARS-Cov-2 on genome stability and DNA damage responses (DDRs) has received relatively little attention. However, it is now becoming clear that the virus causes damage to cellular DNA, as shown by the presence of micronuclei, DNA repair foci and increased comet tails in infected cells. This review considers recent evidence indicating how SARS-CoV-2 causes genome instability, deregulates the cell cycle and targets specific components of DDR pathways. The significance of the virus's ability to cause cellular senescence is also considered, as are the implications of genome instability for patients suffering from long COVID.

Plant Cell-Engineered Gold Nanoparticles Conjugated to Quercetin Inhibit SARS-CoV-2 and HSV-1 Entry

Recent studies have revealed considerable promise in the antiviral properties of metal nanomaterials, specifically when biologically prepared. This study demonstrates for the first time the antiviral roles of the plant cell-engineered gold nanoparticles (pAuNPs) alone and when conjugated with quercetin (pAuNPsQ). We show here that the quercetin conjugated nanoparticles (pAuNPsQ) preferentially inhibit the cell entry of two medically important viruses-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and herpes simplex virus type-1 (HSV-1) using different mechanisms. Interestingly, in the case of SARS-CoV-2, the pre-treatment of target cells with pAuNPsQ inhibited the viral entry, but the pre-treatment of the virus with pAuNPsQ did not affect viral entry into the host cell. In contrast, pAuNPsQ demonstrated effective blocking capabilities against HSV-1 entry, either during the pre-treatment of target cells or by inducing virus neutralization. In addition, pAuNPsQ also significantly affected HSV-1 replication, evidenced by the plaque-counting assay. In this study, we also tested the chemically synthesized gold nanoparticles (cAuNPs) of identical size and shape and observed comparable effects. The versatility of plant cell-based nanomaterial fabrication and its modification with bioactive compounds opens a new frontier in therapeutics, specifically in designing novel antiviral formulations.

Omics data analysis reveals common molecular basis of small cell lung cancer and COVID-19

The impact of COVID-19 infection on individuals with small cell lung cancer (SCLC) poses a serious threat. Unfortunately, the molecular basis of this severe comorbidity has yet to be elucidated. The present study addresses this gap utilizing publicly available omics data of COVID-19 and SCLC to explore the key molecules and associated pathways involved in the convergence of these diseases. Findings revealed 402 genes, that exhibited differential expression patterns in SCLC patients and also play a pivotal role in COVID-19 pathogenesis. Subsequent functional enrichment analyses identified relevant ontologies and pathways that are significantly associated with these genes, revealing important insights into their potential biological, molecular and cellular functions. The protein-protein interaction network, constructed under four combinatorial topological assessments, highlighted SMAD3, CAV1, PIK3R1, and FN1 as the primary components to this comorbidity. Our results suggest that these components significantly regulate this cross-talk triggering the PI3K-AKT and TGF-β signaling pathways. Lastly, this study made a multi-step computational attempt and identified corylifol A and ginkgetin from natural sources that can potentially inhibit these components. Therefore, the outcomes of this study offer novel perspectives on the common molecular mechanisms underlying SCLC and COVID-19 and present future opportunities for drug development.Communicated by Ramaswamy H. Sarma.