OBJECTIVES: To analyze the association of CHMP2B expression level of with clinicopathological characteristics and prognosis of clear cell renal cell carcinoma (CRCC) and the possible role of CHMP2B in tumorigenesis and progression of CRCC. METHODS: RNAseq data of CRCC were downloaded from the TCGA database for analysis of CHMP2B expression levels in tumor and adjacent tissues and their correlation with clinicopathological characteristics of the patients. Survival outcomes of the patients with high and low CHMP2B expressions were analyzed using the Kaplan-Meier model, and the COX risk regression model was used for identifying the prognostic factors of the patients. The correlation between CHMP2B expression and immune infiltration, its co-expressed genes, and the effect of CHMP2B gene mutations on immunotherapy responses, and its immunohistochemical expression in CRCC and normal tissues were analyzed. Clinical samples of CRCC were collected to examine CHMP2B expressions using RT-PCR, and cell experiment was carried out to test the effect of CHMP2B overexpression on biological behaviors of CRCC cells. RESULTS: CHMP2B was significantly under-expressed in renal cancer tissues, and its overexpression obviously inhibited the proliferation of CRCC cells in vitro. CHMP2B expression level was significantly correlated with age, gender, lymph node metastasis, and tumor stage, and the patients with low CHMP2B expression had poor survival outcomes. Enrichment and co-expression gene analyses suggested that CHMP2B was mainly involved in viral outgrowth, necrotic apoptosis, endocytosis, and immune-regulatory processes in kidney cancer. CONCLUSIONS CHMP2B is lowly expressed in renal cancer tissues to affect tumor progression and tumor immune processes, and may serve as a prognostic biomarker and therapeutic target for CRCC.
Humans ; Carcinoma, Renal Cell/metabolism* ; Kidney Neoplasms/metabolism* ; Cell Proliferation ; Prognosis ; Cell Line, Tumor ; Male ; Female ; Gene Expression Regulation, Neoplastic

OBJECTIVES: To identify potential molecular targets of quercetin in the treatment of clear cell renal carcinoma (ccRCC). METHODS: The therapeutic targets of quercetin were screened from multiple databases by network pharmacology analysis, and the targets significantly correlated with ccRCC were screened from 4907 plasma proteins using a Mendelian randomization method. The drug-disease network model was constructed to screen the potential key targets. The functions of these targets were evaluated via bioinformatics analysis, and the screened targets were verified in cultured ccRCC cells. RESULTS: Network pharmacology analysis combined with Mendelian randomization identified TP53 (OR=3.325, 95% CI: 1.805-6.124, P=0.0001), ARF4 (OR=0.173, 95% CI: 0.065-0.456, P=0.0003), and DPP4 (OR=0.463, 95% CI: 0.302-0.711, P=0.0004) as the core targets in quercetin treatment of ccRCC. Bioinformatics analysis showed that TP53 was highly expressed in ccRCC, and patients with high TP53 expressions had worse survival outcomes. Molecular docking studies showed that the binding energy between quercetin and TP53 was -5.83 kcal/mol. In cultured 786-O cells, CCK-8 assay and wound healing assay showed that treatment with quercetin significantly inhibited cell proliferation and migration. Quercetin treatment also strongly suppressed the expression of TP53 at both the mRNA and protein levels in 786-O cells as shown by RT-qPCR and Western blotting. CONCLUSIONS TP53 may be the key target of quercetin in the treatment of ccRCC, which sheds light on potential molecular mechanism that mediate the therapeutic effect of quercetin.
Humans ; Quercetin/pharmacology* ; Carcinoma, Renal Cell/genetics* ; Cell Proliferation/drug effects* ; Kidney Neoplasms/genetics* ; Cell Movement/drug effects* ; Tumor Suppressor Protein p53/metabolism* ; Cell Line, Tumor ; Computational Biology

OBJECTIVES: To investigate the effect of Didang Decoction-medicated serum on autophagy in high glucose (HG)-induced rat glomerular endothelial cells (RGECs) and explore the pathway that mediates its effect. METHODS: Primary RGECs were isolated and cultured using sequential sieving combined with collagenase digestion, followed by identification using immunofluorescence assay for factor VIII. High glucose medium was used to induce RGECs to simulate a diabetic environment, and the effects of Didang Decoction-medicated serum and 3-MA (an autophagy inhibitor), either alone or in combination, on autophagy of HG-exposed cells were evaluated by observing autophagic vacuoles using monodansylcadaverine (MDC) staining. RT-qPCR and Western blotting were employed to measure mRNA and protein expression levels of Beclin-1, p62, LC3B, p-PI3K, p-Akt, and p-mTOR. RESULTS: Compared with the control cells, the HG-exposed RGECs showed significantly reduced autophagic fluorescence intensity, decreased Beclin-1 mRNA expression, increased p62 mRNA expression, downregulated Beclin-1 protein and LC3-II/I ratio, and upregulated p62, p-PI3K, p-Akt, and p-mTOR protein levels. Didang Decoction-medicated serum significantly enhanced autophagic fluorescence intensity in HG-exposed cells, increased Beclin-1 mRNA expression, decreased p62 mRNA expression, upregulated Beclin-1 protein, and downregulated p62, p-PI3K, p-Akt, and p-mTOR protein levels. CONCLUSIONS Didang Decoction-medicated serum enhances autophagy in HG-exposed RGECs by regulating the PI3K/Akt/mTOR signaling pathway, which sheds light on a new therapeutic strategy for diabetic nephropathy.
Animals ; Autophagy/drug effects* ; Signal Transduction/drug effects* ; Rats ; TOR Serine-Threonine Kinases/metabolism* ; Drugs, Chinese Herbal/pharmacology* ; Proto-Oncogene Proteins c-akt/metabolism* ; Endothelial Cells/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Glucose ; Cells, Cultured ; Kidney Glomerulus/cytology* ; Rats, Sprague-Dawley

OBJECTIVES: To investigate the mechanism of Qihuang Jianpi Zishen Granules (QJZ) for ameliorating renal damage in MRL/lpr mice. METHODS: With 6 female C57BL/6 mice as the normal control group, 30 female MRL/lpr mice were randomized into model group, QJZ treatment groups at low, moderate and high doses, and prednisone treatment group (n=6). After 8 weeks of treatment, the mice were examined for 24-h urine protein, creatinine and albumin levels, serum levels of IgG, complement 3 (C3), C4, anti-dsDNA, interferon γ (IFN‑γ) and interleukin 17 (IL-17). Kidney tissues were sampled for histopathological examination with HE staining and observation of glomerular ultrastructure changes using transmission electron microscopy (TEM). The expressions of MyD88/NF-κB pathway-related molecules in the kidney tissue were detected using RT-qPCR, Western blotting and immunohistochemistry. RESULTS: Compared with those in the model group, the mice treated with QJZ at the 3 doses and prednisone showed significant reductions in the renal injury biomarkers and serum IgG, anti-dsDNA, IFN‑γ and IL-17 levels and elevation of serum C3 and C4 levels. HE staining revealed lessened glomerular endothelial cell proliferation and mesangial thickening in all the treatment groups. TEM observation further demonstrated reduced electron-dense deposits and diminished inflammatory cell infiltration in the glomeruli in the intervention groups. QJZ at the 3 doses and prednisone treatment all significantly lowered renal expression levels of MyD88, NF-κB, p65 and p52 in the mouse models. CONCLUSIONS QJZ can improve renal damage in MRL/lpr mice possibly by inhibiting overactivation of the MyD88/NF-κB pathway.
Animals ; Drugs, Chinese Herbal/therapeutic use* ; Female ; Mice, Inbred C57BL ; Mice, Inbred MRL lpr ; Myeloid Differentiation Factor 88/metabolism* ; Mice ; NF-kappa B/metabolism* ; Signal Transduction/drug effects* ; Kidney/metabolism* ; Interleukin-17

OBJECTIVES: To investigate the role of ferroptosis in diquat-induced acute kidney injury (AKI) and its molecular mechanisms. METHODS: Transgenic zebrafish models with Tg (Eco.Tshb:EGFP) labeling of the renal tubules and Tg (lyz:dsRed2) labeling of the neutrophils were both divided into control group, gentamicin (positive control) group, diquat poisoning group, ferroptosis inhibitor group. The indicators of kidney injury, inflammatory response, and ferroptosis were examined in the zebrafish, and the changes in expressions of voltage-dependent anion-selective channel protein 1 (VDAC1) and mitochondrial ferritin (FTMT) were detected using Western blotting. RESULTS: AKI induced by diquat exhibited a significant dose-effect relationship, and the severity of injury was proportional to the exposure concentration. Diquat also caused marked oxidative stress and inflammatory responses in the zebrafish models. Rhodamine metabolism assay and HE staining revealed significantly declined glomerular filtration function of the zebrafish as diquat exposure concentration increased. Immunofluorescence staining highlighted significant changes in the expressions of ferroptosis markers GPX4 and FTH1 in zebrafish renal tissues following diquat exposure. In diquat-exposed zebrafish, treatment with ferrostatin-1, a ferroptosis inhibitor, obviously upregulated GPX4 and downregulated FTH1 expressions and improved the metabolic rate of glucan labeled with rhodamine B. Diquat exposure significantly upregulated the expression of VDAC1 and FTMT in zebrafish, and the application of ferrostatin-1 and VBIT-12 (a VDAC1 inhibitor) both caused pronounced downregulation of FTMT expression. CONCLUSIONS Ferroptosis is a critical mechanism underlying diquat-induced AKI, in which VDAC1 and FTMT play important regulatory roles, suggesting their potential as therapeutic target for AKI caused by diquat.
Animals ; Zebrafish ; Ferroptosis/drug effects* ; Acute Kidney Injury/chemically induced* ; Diquat/toxicity* ; Animals, Genetically Modified ; Voltage-Dependent Anion Channel 1/metabolism* ; Ferritins/metabolism* ; Oxidative Stress

OBJECTIVES: To examine the changes in serum levels of endoplasmic reticulum stress (ERS) proteins GRP78/CHOP in patients with lupus nephritis (LN) and analyze their diagnostic value and association with renal pathological features. METHODS: From a sample bank established based on a multicenter cohort study of systemic lupus erythematosus (SLE), 60 LN patients and 35 SLE patients without renal involvement were randomly selected. ELISA was used to detect serum levels of GRP78 and CHOP in the patients to analyze their correlation with clinical features and their diagnostic ability for LN and active LN. MRL/lpr mice were used as an animal model of LN to examine their serum levels of GRP78 and CHOP expression and renal expressions of endoplasmic reticulum apoptosis-related proteins. RESULTS: Serum GRP78 and CHOP levels were significantly higher in LN patients than in SLE patients without renal involvement (P<0.05), and were also higher in active LN patients than in patients in the stable phase (P<0.05). Correlation analysis indicated that serum GRP78 and CHOP levels were positively correlated with SLEDAI scores and 24-h urinary protein. ROC analysis showed that CHOP had a high diagnostic ability for LN (AUC=0.762) and active LN (AUC=0.933). Consistent with the clinical findings, serum GRP78 and CHOP levels were elevated in LN mice, and the expressions of PERK and IRE1α pathway proteins were also increased in the kidneys of the mice. TUNEL staining showed increased renal cell apoptosis and elevated renal expressions of apoptosis-related proteins in LN mice. CONCLUSIONS Serum levels of GRP78/CHOP are increased in LN patients possibly in association with ERS-induced apoptosis mediated by the PERK/IRE1α dual pathway.
Endoplasmic Reticulum Chaperone BiP ; Lupus Nephritis/blood* ; Transcription Factor CHOP/blood* ; Heat-Shock Proteins/blood* ; Animals ; Apoptosis ; Humans ; Mice ; Mice, Inbred MRL lpr ; Female ; Adult ; Endoribonucleases/metabolism* ; Male ; eIF-2 Kinase/metabolism* ; Protein Serine-Threonine Kinases/metabolism* ; Young Adult ; Endoplasmic Reticulum Stress ; Kidney/metabolism* ; Middle Aged ; Signal Transduction

OBJECTIVES: To investigate the therapeutic mechanism of Danzhi Jiangtang Capsule (DZJTC) for repairing renal vascular endothelial injury in rats with diabetic nephropathy (DN). METHODS: Fifty male SD rat models of DN, established by left nephrectomy, high-sugar and high-fat diet and streptozotocin injection, were randomized into DN model group, low-, medium-, and high-dose DZJTC treatment groups, and DAPT (a γ-secretase inhibitor) treatment group, with 10 rats with normal feeding as the control group. DZJTC was administered by daily gavage at 0.315, 0.63, or 1.26 g/kg, and DAPT (20 mg/kg, dissolved in 50% CMC-Na solution) was given by gavage every other day for 4 weeks; normal saline was given in the control and model groups. After treatment, the levels of creatinine (CRE), blood urea nitrogen (BUN), and microalbuminuria (mALB) were detected with ELISA, and renal pathologies were observed by transmission electron microscopy. Renal expressions of vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1) were measured by immunohistochemistry, and the protein expressions of CD31 and Notch signaling pathway components were detected using Western blotting. RESULTS: The rat models of DN showed significantly increased CRE, BUN, and mALB levels, obvious renal pathologies under electron microscopy, increased renal VEGF, ET-1 and CD31 expressions, and upregulated Notch1, NICD, and MAML1 protein levels. Treatment with DZJTC at the 3 doses and DAPT significantly reduced CRE, BUN, and mALB levels, improved renal pathology, decreased VEGF, ET-1 and CD31 expressions, and lowered Notch1, NICD and MAML1 levels, and the effects were the most pronounced with high-dose DZJTC. CONCLUSIONS DZJTC ameliorates hyperproliferation and dysfunction of renal vascular endothelium in DN rats possibly by regulating renal VEGF and ET-1 levels via inhibiting NICD- and MAML1-mediated Notch signaling pathway.
Animals ; Male ; Drugs, Chinese Herbal/therapeutic use* ; Rats ; Rats, Sprague-Dawley ; Signal Transduction/drug effects* ; Diabetic Nephropathies/drug therapy* ; Receptor, Notch1/metabolism* ; Kidney/blood supply* ; Diabetes Mellitus, Experimental ; Down-Regulation ; Endothelium, Vascular/metabolism* ; Nuclear Proteins/metabolism*

OBJECTIVES: To investigate the efficacy of Qihuang Jianpi Zishen Granules (QJZ) for inhibiting renal B cell differentiation in MRL/lpr mice and explore its underlying mechanism. METHODS: Thirty 8-week-old female MRL/lpr mice were randomly divided into model group, QJZ group, prednisone (Pred) group, QJZ+Pred group, and AIM2 inhibitor group (n=6), with 6 8-week-old female C57BL/6 mice as the normal control group. After treatments with normal saline, QJZ, Pred, or AIM2 inhibitor for 8 weeks, the mice were examined for urinary total protein-to-creatinine ratio (TPCR) and albumin-to-creatinine ratio (ACR), serum creatinine (Cr) and blood urea nitrogen (BUN) levels, and renal histopathology (with HE, Masson, and PAS staining) and ultrastructural changes (with electron microscopy). ELISA, immunohistochemistry, immunofluorescence staining and flow cytometry were used to detect blood levels of anti-dsDNA antibodies, cytokines and chemokines, renal deposition of complement components C3 and C4, renal expressions of AIM2, CD19, CD27 and CD138, and changes in splenic B lymphocyte subsets. The effect of QJZ on the AIM2/Blimp-1/Bcl-6 signaling axis was examined using Western blotting. RESULTS: QJZ treatment significantly improved Cr, BUN, TPCR and ACR in MRL/lpr mice, ameliorated renal pathologies, reduced the expressions of ds-DNA, BAFF, IL-21, CXCL12, CXCL13, C3 and C4, and increased IL-10 levels. QJZ significantly downregulated renal expressions of the key B-cell transcription factors Blimp-1 and XBP-1, upregulated Bcl-6 and PAX5 expressions, inhibited B-cell differentiation, and lowered the expressions of AIM2, CD27, CD138 and CD69. Inhibition of AIM2 similarly reduced renal Blimp-1 and XBP-1 expressions, increased Bcl-6 and PAX5 levels, suppressed B-cell differentiation, decreased IgG production, reduced C3 and C4 deposition, and alleviated renal pathology in MRL/lpr mice. CONCLUSIONS QJZ inhibits B cell differentiation and alleviates renal damage in systemic lupus erythematosus possibly by suppressing the AIM2/Blimp-1/Bcl-6 signaling pathway.
Animals ; Drugs, Chinese Herbal/therapeutic use* ; Mice, Inbred MRL lpr ; Female ; Mice ; Mice, Inbred C57BL ; Cell Differentiation/drug effects* ; B-Lymphocytes/drug effects* ; Proto-Oncogene Proteins c-bcl-6/metabolism* ; Kidney/drug effects* ; DNA-Binding Proteins/metabolism* ; Signal Transduction ; Lupus Nephritis

Renal ischemia-reperfusion injury (IRI) is a major contributor to acute kidney injury (AKI), leading to substantial morbidity and mortality. Spexin (SPX), a 14-amino acid endogenous peptide involved in metabolic regulation and immune modulation, has not yet been studied in the context of chronic treatment and renal IRI. This study evaluated the effects of exogenous SPX on renal function, histopathological changes, and molecular pathways in both IRI-induced injured and healthy kidneys. Twenty-eight male BALB/c mice were divided into four groups: control, SPX, IRI, and SPX+IRI. IRI was induced by 30 minutes of bilateral renal ischemia followed by 6 hours of reperfusion. Renal injury markers, histopathological changes, inflammatory mediators, apoptotic markers, and fibrosis-related proteins were analyzed. SPX significantly exacerbated IRI-induced kidney injury by activating the Wnt/β-catenin signaling pathway and promoting the upregulation of pro-inflammatory, pro-apoptotic, and pro-fibrotic mediators. It is noteworthy that SPX exerted more severe deleterious nephrotoxic effects in the healthy kidney compared to those observed in the IRI-induced injured kidney. These findings indicate that chronic treatment with SPX administration may have intrinsic pro-inflammatory, pro-apoptotic and fibrotic properties, raising concerns about its therapeutic potential. Further research is needed to clarify its physiological role and therapeutic implications in kidney diseases.
Animals ; Reperfusion Injury/chemically induced* ; Male ; Mice, Inbred BALB C ; Mice ; Acute Kidney Injury/metabolism* ; Kidney/blood supply* ; Peptide Hormones/adverse effects* ; Apoptosis/drug effects* ; Wnt Signaling Pathway/drug effects* ; Disease Models, Animal

Peroxisome proliferator activated receptor-α (PPAR-α) is significantly expressed in various tissues such as the liver, kidney, myocardium, and skeletal muscle, which plays a central role in the development of various diseases by regulating key physiological processes such as energy homeostasis, redox balance, inflammatory response, and ferroptosis. As an important metabolic and excretory organ of the body, renal dysfunction can lead to water and electrolyte imbalance, toxin accumulation, and multiple system complications. The causes of kidney injury are complex and diverse, including acute injury factors (such as ischemia/reperfusion, nephrotoxic drugs, septic shock, and immune glomerulopathy), as well as chronic progressive causes [such as metabolic disease-related nephropathy, hypertensive nephropathy (HN)], and risk factors such as alcohol abuse, obesity, and aging. This review briefly describes the structure, function, and activity regulation mechanism of PPAR-α, systematically elucidates the molecular regulatory network of PPAR-α in the pathological process of kidney injury including acute kidney injury (AKI) such as renal ischemia/reperfusion injury (IRI), drug-induced AKI, sepsis-associated acute kidney injury (SA-AKI), glomerulonephritis, chronic kidney disease (CKD) such as diabetic nephropathy (DN), HN, and other kidney injury, and summarizes the mechanisms related to PPAR-α regulation of kidney injury, including regulation of metabolism, antioxidation, anti-inflammation, anti-fibrosis, and anti-ferroptosis. This review also evaluates PPAR-α's medical value as a novel therapeutic target, and aims to provide theoretical basis for the development of kidney protection strategies based on PPAR-α targeted intervention.
Humans ; PPAR alpha/metabolism* ; Acute Kidney Injury/therapy* ; Animals ; Kidney/metabolism*