Natural intestinal metabolite xylitol reduces BRD4 levels to mitigate renal fibrosis.

Renal fibrosis is a typical pathological change from chronic kidney disease (CKD) to end-stage renal failure, which presents significant challenges in prevention and treatment. The progression of renal fibrosis is closely associated with the "gut-kidney axis," therefore, although clinical intervention to modulate the "gut-kidney axis" imbalance associated with renal fibrosis brings hope for its treatment. In this study, we first identified the close relationship between renal fibrosis development and the intestinal microenvironment through fecal microtransplantation and non-absorbable antibiotics experiments. Then, we analyzed the specific connection between the intestinal microenvironment and renal fibrosis using microbiomics and metabolomics, screening for the differential intestinal metabolite. Potential metabolite action targets were initially identified through network simulation of molecular docking and further verified by molecular biology experiment. We used flow cytometry, TUNEL apoptosis staining, immunohistochemistry, and Western blotting to assess renal injury and fibrosis extent, exploring the potential role of gut microbial metabolite in renal fibrosis development. We discovered that CKD-triggered alterations in the intestinal microenvironment exacerbate renal injury and fibrosis. When metabolomic analysis was combined with experiments in vivo, we found that the differential metabolite xylitol delays renal injury and fibrosis development. We further validated this hypothesis at the cellular level. Mechanically, bromodomain-containing protein 4 (BRD4) protein exhibits strong binding with xylitol, and xylitol alleviates renal fibrosis by inhibiting BRD4 and its downstream transforming growth factor-ß (TGF-ß) pathway. In summary, our findings suggest that the natural intestinal metabolite xylitol mitigates renal fibrosis by inhibiting the BRD4-regulated TGF-ß pathway.

Ferrous Selenide Stabilized Black Phosphorus Heterojunction Sonosensitizer for MR Imaging-Guided Sonodynamic Therapy of Bladder Cancer.

It is urgent to develop an alternative dynamic therapy-based method to overcome the limited efficacy of traditional therapy methods for bladder cancer and the damage caused to patients. Sonodynamic therapy (SDT) has the advantages of high tissue penetration, high spatiotemporal selectivity, and being non-invasive, representing an emerging method for eradicating deep solid tumors. However, the effectiveness of SDT is often hindered by the inefficient production of reactive oxygen species and the nondegradability of the sonosensitizer. To improve the anti-tumor effect of SDT on bladder cancer, herein, a BP-based heterojunction sonosensitizer (BFeSe2) was synthesized by anchoring FeSe2 onto BP via P-Se bonding to enhance the stability and the effect of SDT. As a result, BFeSe2 showed great cytotoxicity to bladder cancer cells under ultrasound (US) irradiation. BFeSe2 led to a notable inhibition effect on tumor growth in subcutaneous tumor models and orthotopic tumor models under US irradiation. In addition, BFeSe2 could also enhance T2-weighted magnetic resonance imaging (MRI) to achieve monitoring and guide treatment of bladder cancer. In general, BFeSe2 sonosensitizer integrates MRI functions for precise treatment, promising great clinical potential for the theranostics of bladder cancer.

Histone deacetylase 6 suppression of renal tubular epithelial cell promotes interstitial mineral deposition via alpha-tubulin acetylation.

Randall's plaque (RP) is derived from interstitial mineral deposition and is highly prevalent in renal calcium oxalate (CaOx) stone disease, which is predictive of recurrence. This study shows that histone deacetylase 6 (HDAC6) levels are suppressed in renal tubular epithelial cells in RP samples, in kidney tissues of hyperoxaluria rats, and in hyper-oxalate-treated or mineralized cultured renal tubular epithelial (MDCK) cells in vitro. Mineral deposition in MDCK cells was exacerbated by HDAC6 inhibition but alleviated by HDAC6 overexpression. Surprisingly, the expression of some osteogenic-associated proteins, were not increased along with the increasing of mineral deposition, and result of single-cell RNA sequencing of renal papillae samples revealed that epithelial cells possess lower calcific activity, suggesting that osteogenic-transdifferentiation may not have actually occurred in tubular epithelial cells despite mineral deposition. The initial mineral depositions facilitated by HDAC6 inhibitor were localized in extracellular dome rather than inside the cells, moreover, suppression of HDAC6 significantly increased the calcium content of co-cultured renal interstitial fibroblasts (NRK49F) and enhanced mineral deposition of indirectly co-cultured NRK49F cells, suggesting that HDAC6 may influence trans-MDCK monolayer secretion of mineral. Further experiments revealed that this regulatory role was partially alpha-tubulinLys40 acetylation dependent. Collectively, these results suggest that hyper-oxalate exposure led to HDAC6 suppression in renal tubular epithelial cells, which may contribute to interstitial mineral deposition by promoting alpha-tubulinLys40 acetylation. Therapeutic agents that influence HDAC6 activity may be beneficial in preventing RP and CaOx stone formation.

Cell Protection and Crystal Endocytosis Inhibition by Sulfated Laminaria Polysaccharides Against Nano-COM-Induced Oxidative Damage in Renal Epithelial Cells.

Background: The damage to renal tubular epithelial cells is closely related to the formation of kidney stones. At present, research on drugs that can protect cells from damage remains limited. Methods: This study aims to explore the protective effects of four different sulfate groups (-OSO3 -) of Laminaria polysaccharides (SLPs) on human kidney proximal tubular epithelial (HK-2) cells and determine the difference in the endocytosis of nano-sized calcium oxalate monohydrate (COM) crystals before and after protection. COM with a size of 230 ± 80 nm was used to damage HK-2 cells to establish a damage model. The protection capability of SLPs (LP0, SLP1, SLP2, and SLP3) with -OSO3 - contents of 0.73, 15, 23, and 31%, respectively, against COM crystal damage and the effect of SLPs on the endocytosis of COM crystals were studied. Results: Compared with that of the SLP-unprotected COM-injured group, the cell viability of the SLP-protected group was improved, healing capability was enhanced, cell morphology was restored, production of reactive oxygen species was reduced, mitochondrial membrane potential and lysosome integrity were increased, intracellular Ca2+ level and autophagy were decreased, cell mortality was reduced, and internalized COM crystals were lessened. The capability of SLPs to protect cells from damage and inhibit the endocytosis of crystals in cells enhanced with an increase in the -OSO3 - content of SLPs. Conclusions: SLPs with a high -OSO3 - content may become a potential green drug for preventing the formation of kidney stones.

Designing Intelligent Nanomaterials to Achieve Highly Sensitive Diagnoses and Multimodality Therapy of Bladder Cancer.

Bladder cancer (BC) is among the most common malignant tumors of the genitourinary system worldwide. In recent years, the rate of BC incidence has increased, and the recurrence rate is high, resulting in poor quality of life for patients. Therefore, how to develop an effective method to achieve synchronous precise diagnoses and BC therapies is a difficult problem to solve clinically. Previous reports usually focus on the role of nanomaterials as drug delivery carriers, while a summary of the functional design and application of nanomaterials is lacking. Summarizing the application of functional nanomaterials in high-sensitivity diagnosis and multimodality therapy of BC is urgently needed. This review summarizes the application of nanotechnology in BC diagnosis, including the application of nanotechnology in the sensoring of BC biomarkers and their role in monitoring BC. In addition, conventional and combination therapies strategy in potential BC therapy are analyzed. Moreover, different kinds of nanomaterials in BC multimodal therapy according to pathological features of BC are also outlined. The goal of this review is to present an overview of the application of nanomaterials in the theranostics of BC to provide guidance for the application of functional nanomaterials to precisely diagnose and treat BC.

Accurate diagnosis of prostate cancer with CRISPR-based nucleic acid test strip by simultaneously identifying PCA3 and KLK3 genes.

Although serum prostate specific antigen (PSA) testing could decrease the morality of prostate cancer (PCa), its low specificity usually led to misdiagnosis due to prostatitis or benign prostatic hyperplasia (BPH). Prostate cancer antigen 3 (PCA3) as an alternative prostate tumor-specificity biomarker could be used to increase the specificity of PCa diagnosis, however, it usually required sophisticated operation and expensive equipment for routine detection. Herein, we constructed an early detection platform for prostate cancer with reverse transcriptase-recombinase aided amplification (RT-RAA) and clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 based nucleic acid test strip. The amplicons of PCA3 and kallikrein related peptidase 3 (KLK3) gene, which amplified simultaneously by single-amplification unit of RT-RAA were specifically recognized by Cas9-sgRNA and visual on the nucleic acid test strip by naked eyes without instruments. Simultaneously detection of PCA3 and KLK3 gene could improve specificity and accuracy of the diagnosis but avoid mutual interference. In addition, the platform presented a detection limit of 500 fg/µL and 50 fg/µL in PCA3 and KLK3 gene, respectively. Furthermore, the analysis result of signal ratio of PCA3 to KLK3 gene of urine and peripheral blood specimens from 32 men with suspected prostate cancer on test strips illustrated that the area under the curve values of urine and peripheral blood specimens were 0.998 and 1.0 respectively. In summary, our study highlighted a facile strategy to design an accurate prostate cancer gene detection platform which had the potential to conduct prostate cancer early detection in the resource-limited or other point-of-care testing (POCT) environments.

Cerium oxide-based nanozyme suppresses kidney calcium oxalate crystal depositions via reversing hyperoxaluria-induced oxidative stress damage.

Oxidative stress damage to renal epithelial cells is the main pathological factor of calcium oxalate calculi formation. The development of medicine that could alleviate oxidative damage has become the key to the prevention and treatment of urolithiasis. Herein, porous nanorods CeO2 nanoparticles (CNPs) were selected from CeO2 with different morphologies as an antioxidant reagent to suppress kidney calcium oxalate crystal depositions with excellent oxidation resistance due to its larger specific surface area. The reversible transformation from Ce3+ to Ce4+ could catalyze the decomposition of excess free radicals and act as a biological antioxidant enzyme basing on its strong ability to scavenge free radicals. The protection capability of CNPS against oxalate-induced damage and the effect of CNPS on calcium oxalate crystallization were studied. CNPS could effectively reduce reactive oxygen species production, restore mitochondrial membrane potential polarity, recover cell cycle progression, reduce cell death, and inhibit the formation of calcium oxalate crystals on the cell surface in vitro. The results of high-throughput sequencing of mRNA showed that CNPs could protect renal epithelial cells from oxidative stress damage caused by high oxalate by suppressing the expression gene of cell surface adhesion proteins. In addition, CNPS can significantly reduce the pathological damage of renal tubules and inhibit the deposition of calcium oxalate crystals in rat kidneys while having no significant side effect on other organs and physiological indicators in vivo. Our results provide a new strategy for CNPS as a potential for clinical prevention of crystalline kidney injury and crystal deposition.

Distinct immune and inflammatory response patterns contribute to the identification of poor prognosis and advanced clinical characters in bladder cancer patients.

Due to the molecular heterogeneity, most bladder cancer (BLCA) patients show no pathological responses to immunotherapy and chemotherapy yet suffer from their toxicity. This study identified and validated three distinct and stable molecular clusters of BLCA in cross-platform databases based on personalized immune and inflammatory characteristics. H&E-stained histopathology images confirmed the distinct infiltration of immune and inflammatory cells among clusters. Cluster-A was characterized by a favorable prognosis and low immune and inflammatory infiltration but showed the highest abundance of prognosis-related favorable immune cell and inflammatory activity. Cluster-B featured the worst prognosis and high immune infiltration, but numerous unfavorable immune cells exist. Cluster-C had a favorable prognosis and the highest immune and inflammatory infiltration. Based on machine learning, a highly precise predictive model (immune and inflammatory responses signature, IIRS), including FN1, IL10, MYC, CD247, and TLR2, was developed and validated to identify the high IIRS-score group that had a poor prognosis and advanced clinical characteristics. Compared to other published models, IIRS showed the highest AUC in 5 years of overall survival (OS) and a favorable predictive value in predicting 1- and 3- year OS. Moreover, IIRS showed an excellent performance in predicting immunotherapy and chemotherapy's response. According to immunohistochemistry and qRT-PCR, IIRS genes were differentially expressed between tumor tissues with corresponding normal or adjacent tissues. Finally, immunohistochemical and H&E-stained analyses were performed on the bladder tissues of 13 BLCA patients to further demonstrate that the IIRS score is a valid substitute for IIR patterns and can contribute to identifying patients with poor clinical and histopathology characteristics. In conclusion, we established a novel IIRS depicting an IIR pattern that could independently predict OS and acts as a highly precise predictive biomarker for advanced clinical characters and the responses to immunotherapy and chemotherapy.

Allicin suppressed Escherichia coli-induced urinary tract infections by a novel MALT1/NF-κB pathway.

Escherichia coli (E. coli) strains cause the majority of urinary tract infections (UTIs) and are resistant to various antibiotics. Therefore, it is imperative to explore novel host-target therapies. As a famous food and condiment, garlic (Allium sativum L.) is widely used in medicine, but its exact key targets in UTIs remain elusive. To identify the major active ingredient of garlic and its molecular target against UTIs, a network pharmacology analysis was carried out, and allicin was revealed to be a key active component in garlic acting on UTIs. By molecular docking, allicin showed a good binding affinity to mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1). The possible regulatory mechanisms of allicin against UTIs were based on the modules of immune and inflammatory responses mainly through AKT/NF-κB signaling. Next, an E. coli-stimulated human uroepithelial cell (HUC) model was established to confirm the anti-infective effect of allicin. The results showed that allicin could significantly inhibit the upregulation of MALT1, the AKT/NF-κB pathway, and cytokines (IL-6 and IL-1ß). HUCs pretreated with the PI3K inhibitor or transfected with MALT-siRNA also partly suppressed the activation of the AKT/NF-κB pathway and cytokines. Furthermore, by establishing the PCA algorithm to evaluate the therapeutic score, allicin was proved to achieve the optimal therapeutic effects compared with the PI3K inhibitor and siRNA-MALT1. Moreover, in rats with an E. coli-induced UTI model, allicin significantly alleviated the infection and up-regulation of MALT1 expression in the bladders, a marked increase in the bacterial load of urine, and deviations in serum biochemical parameters. In conclusion, allicin exerts anti-infective effects in UTIs mainly via the MALT1/NF-κB axis or AKT/NF-κB pathway, which provides a theoretical basis for understanding the function of allicin against UTIs and facilitates its clinical application.

Preoperative antibiotic therapy exceeding 7 days can minimize infectious complications after percutaneous nephrolithotomy in patients with positive urine culture.

PURPOSE: To explore an appropriate duration of antibiotic therapy before percutaneous nephrolithotomy (PCNL) in patients with positive urine culture. METHODS: From March 2016 to May 2018, consecutive patients with positive urine culture undergoing PCNL were prospectively registered. Initial preoperative antibiotics were given empirically. If needed, antibiotics were upgraded or adjusted to susceptible antibiotic after obtaining antibiotic-sensitivity test. Postoperative systemic inflammatory response syndrome (SIRS) was the primary outcome. RESULTS: Among the 220 participants, the incidence of positive stone culture and SIRS were 85.5% and 36.8%. Escherichia coli (53.6%, 44.5%) and Proteus mirabilis (8.2%, 10.0%) were the top two bacteria in urine and stones. In univariable analysis, patients with postoperative SIRS had a higher rate of stone culture positivity (97.5% VS 78.4%, P < 0.001) and a shorter duration of preoperative antibiotics therapy (3.4 ± 2.7 days versus 4.2 ± 2.8 days, P = 0.037). The landscape of SIRS showed a declining trend as the elongation of preoperative antibiotics (P = 0.039). In a day-by-day comparison, SIRS was less prevalent in patients treated by pre-PCNL antibiotics ≥ 7 days than in those with antibiotics ≤ 6 days (21.7% VS 40.8%, P = 0.017). Multivariable logistic regression confirmed positive stone culture (P = 0.001, OR 11.115) as an independent risk factor and pre-PCNL antibiotics ≥ 7 days (P = 0.048, OR 0.449) as an independent protective factor for SIRS. Preoperative antibiotic ≥ 7 days decreased SIRS from 45.4 to 27.8% and from 9.1 to 0% in patients with a positive and negative stone culture, respectively. CONCLUSION: Exceeding seven days should be appropriate duration of antibiotic therapy before PCNL in patients with positive urine cultures.

Escherichia coli Aggravates Calcium Oxalate Stone Formation via PPK1/Flagellin-Mediated Renal Oxidative Injury and Inflammation.

Escherichia coli (E. coli) is closely associated with the formation of kidney stones. However, the role of E. coli in CaOx stone formation is not well understood. We explored whether E. coli facilitate CaOx stone formation and its mechanism. Stone and urine cultures were reviewed from kidney stone formers. The ability of calcium oxalate monohydrate (COM) aggregation was detected to evaluate the influence of uropathogenic E. coli, then gel electrophoresis and nanoLC-MS/MS to detect the crystal-adhered protein. Flagellin (Flic) and polyphosphate kinase 1 (PPK1) were screened out following detection of their role on crystal aggregation, oxidative injury, and inflammation of HK-2 cell in vitro. By transurethral injection of wild-type, Ppk1 mutant and Flic mutant strains of E. coli and intraperitoneally injected with glyoxylate in C57BL/6J female mice to establish an animal model. We found that E. coli was the most common bacterial species in patients with CaOx stone. It could enhance CaOx crystal aggregation both in vitro and in vivo. Flagellin was identified as the key molecules regulated by PPK1, and both of them could facilitate the crystal aggregation and mediated HK-2 cell oxidative injury and activated the inflammation-related NF-κB/P38 signaling pathway. Wild-type strain of E. coli injection significantly increased CaOx deposition and enhanced oxidative injury and inflammation-related protein expression, and this effect could be reversed by Ppk1 or Flic mutation. In conclusion, E. coli promotes CaOx stone formation via enhancing oxidative injury and inflammation regulated by the PPK1/flagellin, which activated NF-κB/P38 pathways, providing new potential drug targets for the renal CaOx calculus precaution and treatment.

Inhibition of LIM kinase reduces contraction and proliferation in bladder smooth muscle.

Overactive bladder (OAB) is the most bothersome symptom in lower urinary tract symptoms (LUTS). Current pharmacologic treatment aims to inhibit detrusor contraction; however, shows unsatisfied efficacy and high discontinuation rate. LIM kinases (LIMKs) promote smooth muscle contraction in the prostate; however, their function in the bladder smooth muscle remains unclear. Here, we studied effects of the LIMK inhibitors on bladder smooth muscle contraction and proliferation both in vitro and in vivo experiments. Bladder expressions of LIMKs are elevated in OAB rat detrusor tissues. Two LIMK inhibitors, SR7826 and LIMKi3, inhibit contraction of human detrusor strip, and cause actin filament breakdown, as well as cell proliferation reduction in cultured human bladder smooth muscle cells (HBSMCs), paralleled by reduced cofilin phosphorylation. Silencing of LIMK1 and LIMK2 in HBSMCs resulted in breakdown of actin filaments and decreased cell proliferation. Treatment with SR7826 or LIMKi3 decreased micturition frequency and bladder detrusor hypertrophy in rats with bladder outlet obstruction. Our study suggests that LIMKs may promote contraction and proliferation in the bladder smooth muscle, which could be inhibited by small molecule LIMK inhibitors. LIMK inhibitors could be a potential therapeutic strategy for OAB- related LUTS.

Enhanced Antibiotic Treatment Based on Positive Urine Dipstick Infection Test Before Percutaneous Nephrolithotomy Did Not Prevent Postoperative Infection in Patients with Negative Urine Culture.

Introduction: Urinary tract infection (UTI) should be treated before percutaneous nephrolithotomy (PCNL). However, the most appropriate treatment strategy in patients with negative urine culture but positive urine dipstick infection test (positive urinary leukocyte or nitrite reaction) remains unclear. Materials and Methods: From August 2016 to February 2018, 806 consecutive patients who had undergone the first-stage PCNL with negative urine culture were included. Preoperative urinalysis, antibiotic treatment, intraoperative stone culture, and postoperative systemic inflammatory response syndrome (SIRS) were prospectively recorded. The primary outcome was SIRS. The impact of preoperative antibiotics on preoperative UTI, stone culture, and postoperative SIRS was studied. Results: Among the 806 participants, the rate of positive urine dipstick infection test and SIRS were 26.8% and 7.2%, respectively. In univariable analysis, positive urinary nitrite (p < 0.001), positive urinary leukocytes (p < 0.001), positive urine dipstick infection test (p < 0.001), longer duration of pre-PCNL antibiotics (p = 0.001), higher level of pre-PCNL antibiotics (p = 0.010), infection stones (p = 0.001), and positive stone culture (p < 0.001) were risk factors for SIRS. However, multivariable analysis showed that positive stone culture (p = 0.004) and prolonged preoperative treatment with antibiotics (p = 0.021) were independent risk factors for SIRS. Although preoperative antibiotics reduced the incidence of positive urine leukocyte (p < 0.001) or nitrite reactions (p < 0.001), prolonged or upgraded preoperative antibiotics did not affect the incidence of positive stone culture. Whether stone culture was positive (p = 0.023) or negative (p = 0.025), prolonged preoperative treatment with antibiotics was associated with a higher incidence of SIRS. Conclusions: Enhanced preoperative antibiotic treatment based on positive urine dipstick infection tests was insufficient to reduce the incidence of positive stone culture but increased the risk of SIRS after PCNL in patients with negative urine cultures.

Glycine suppresses kidney calcium oxalate crystal depositions via regulating urinary excretions of oxalate and citrate.

An abnormal urine composition is a key reason for kidney stone formation, but little is known about the roles of small metabolites in the urine during kidney stone formation. Here, we found urine glycine in patients with kidney calcium oxalate (CaOx) stone was significantly lower than that in healthy people via 1 H NMR spectra detection, and investigated the role and underlying mechanism of glycine in the regulation of CaOx stone formation. Our results showed that glycine could significantly attenuate ethylene glycol-induced CaOx crystal depositions in rat kidney via decreasing urine oxalate and increasing urine citrate. Mechanism studies revealed that glycine could decrease urine oxalate through downregulating Slc26a6 expression, whereas increase urine citrate via inhibiting Nadc1 expression. Moreover, glycine decreased the protein expression of both Slc26a6 and Nadc1 via increasing the expression of miRNA-411-3p, which directly bound to the 3'-untranslated regions of Slc26a6 and Nadc1 messenger RNAs, in vitro and in vivo. Together, our results revealed a novel role of glycine in the regulation of kidney CaOx crystal formation and provided a potential target for the treatment of kidney CaOx stone.

Dissecting and Evaluating the Therapeutic Targets of Coptis Chinensis Franch in the Treatment of Urinary Tract Infections Induced by Escherichia coli.

Coptis chinensis Franch (CCF) is extensively used in the treatment of inflammatory-related diseases. Accumulating studies have previously demonstrated the anti-inflammatory properties of CCF, yet data on its exact targets against urinary tract infections (UTIs) remain largely unknown. Therefore, the present study decodes the potential targets of action of CCF against UTIs by network pharmacology combined with experiment evaluations. Based on the pharmacology network analysis, the current study yielded six core ingredients: quercetin, palmatine (R)-canadine, berlambine, berberine, and berberrubine. The protein-protein interaction network (PPI) was generated by the string database, and then, four targets (IL6, FOS, MYC, and EGFR) were perceived as the major CCF targets using the CytoNCA plug-in. The results of molecular docking showed that the six core constituents of CCF had strong binding affinities toward the four key targets of UTIs after docking into the crystal structure. The enrichment analysis indicated that the possible regulatory mechanisms of CCF against UTIs were based on the modules of inflammation, immune responses, and apoptosis among others. Experimentally, the Escherichia coli (E. coli) strain CFT073 was applied to establish in vivo and in vitro models. In vivo results revealed that the key targets, IL6 and FOS, are significantly upregulated in rat bladder tissues of UTIs, whereas the expression of MYC and EGFR remained steady. Last, in vitro results further confirmed the therapeutic potential of CCF by reducing the expression of IL6 and FOS. In conclusion, IL6 and FOS were generally upregulated in the progression of E. coli-induced UTIs, whereas the CCF intervention exerted a preventive role in host cells stimulated by E. coli, partially due to inhibiting the expression of IL6 and FOS.

Alteration of the gut microbiota by vinegar is associated with amelioration of hyperoxaluria-induced kidney injury.

Hyperoxaluria is well known to cause renal injury and end-stage kidney disease. Previous studies suggested that the renal function of rats with hyperoxaluria was improved after dietary vinegar intake. However, its underlying mechanisms remain largely unknown. The aim of the present study was to examine changes of gut microbiota and blood and urinary metabolites that associate with changes in kidney function to identify mechanisms involved with vinegar induced amelioration of hyperoxaluria-induced kidney injury. Using an ethylene glycol (EG)-induced hyperoxaluria rat model, we evaluated the effects of the vinegar on renal injury. Oral administration of vinegar (2 ml kg-1 day-1) reduced the elevated serum creatinine, BUN, and protected against hyperoxaluria-induced renal injury, renal fibrosis, and inflammation. Gut microbiota analysis of 16S rRNA gene in the hyperoxaluria-induced renal injury rats showed that vinegar treatment altered their microbial composition, especially the recovery of the levels of the Prevotella, Ruminiclostridium, Alistipes and Paenalcaligenes genus, which were significantly increased in the hyperoxaluria-induced renal injury rats. Additionally, liquid chromatography-mass spectrometry (LC-MS)-based metabolome analysis showed that total of 35 serum and 42 urine metabolites were identified to be associated with protective effects of vinegar on hyperoxaluria-induced renal injury rats. Most of these metabolites were involved in thiamine metabolism, glycerol phosphate shuttle, biotin metabolism, phosphatidylcholine biosynthesis and membrane lipid metabolism. Importantly, the effects of vinegar against renal injury were weakened after depletion of gut microbiota by antibiotic treatment. These results suggest that vinegar treatment ameliorates the hyperoxaluria-induced renal injury by improving the gut microbiota and metabolomic profiles.

LncRNA-miRNA-mRNA expression variation profile in the urine of calcium oxalate stone patients.

BACKGROUND: To explore long-non-coding RNA (lncRNA), microRNA (miRNA) and messenger RNA (mRNA) expression profiles and their biological functions in the urine samples in calcium oxalate (CaOx) patients. METHODS: Five CaOx kidney stone patients were recruited in CaOx stone group and six healthy people were included as control group, whose midstream morning urine was collected before the patients were given any medicine on admission. After total RNA was extracted from urine, microarray of miRNA, mRNA and lncRNA were applied to explore their expression variation. Gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to reveal the gene functions of the dysregulated lncRNA-associated competing endogenous RNA (ceRNA) network. Quantitative real-time PCR were performed on HK-2 cells treated with sodium oxalate (NaOx) to further screen out the differentially expression profiles of these RNAs. RESULTS: A total of nine miRNAs, 883 mRNAs and 1002 lncRNAs were differentially expressed in urine of CaOx patients compared with normal population. GO analysis revealed that most of mRNAs from ceRNA network were enriched in terms of respiratory burst, regulation of mitophagy, and protein kinase regulator activity. KEGG pathway analysis of these genes related to ceRNA network highlight their critical role in pentose phosphate pathway, glyoxylate and dicarboxylate metabolism, and Janus kinase/signal transducer and activator of transcription (JAK-STAT) signaling pathway. Five miRNAs (miR-6796-3p, miR-30d-5p, miR-3192-3p, miR-518b and miR-6776-3p), four mRNAs (NT5E, CDH4, CLEC14A, CCNL1) and six lncRNAs (lnc-TIGD1L2-3, lnc-KIN-1, lnc-FAM72B-4, lnc-EVI5L-1, lnc-SERPINI1-2, lnc-MB-6) from the HK-2 cells induced by NaOx were consistent with the expression changes of microarray results. CONCLUSION: The differential expressed miRNAs, mRNAs and lncRNAs may be associated with numerous variations of the signaling pathways or regulation of metabolism and kinase activity, providing potential biomarkers for early diagnosis of urolithiasis and new basis for further research of urolithiasis mechanism.

Allicin attenuates calcium oxalate crystal deposition in the rat kidney by regulating gap junction function.

Renal calculus is a global common urological disease that is closely related to crystal adhesion and renal tubular epithelial cell impairment. Gap junctions (GJs) and their components (connexins and Cxs) are involved in various pathophysiology processes, but their roles in renal calculi progression are not well defined. Our previous RNA microarray analysis suggests that GJs are one of the key predicted pathways involved in the renal calcium oxalate (CaOx) crystal rat model. In the current study, we found that the Cx43 and Cx32 expression and the GJ function decreased significantly after stimulation with CaOx or sodium oxalate (NaOx) in NRK-52E, MDCK, and HK-2 cells, and Cx43 expression also decreased in renal tissues in renal CaOx crystal model rats. Inhibition of Cx43 in NRK-52E cells by small interference RNA significantly increased the CD44 and androgen receptor expression, and the adhesion between CaOx crystals and cells, which were consistent with the function of GJ inhibitors. On the other hand, after GJ function and Cx43 expression were increased by allicin, diallyl disulfide, or diallyl trisulfide, the impairment of NRK-52E cells by NaOx or other GJ inhibitors and the adhesion between CaOx crystals and renal cells decreased significantly. Furthermore, allicin also increased Cx43 expression and inhibited crystal deposition in rat kidneys. Taken together, our results provide a basis that GJs and Cx43 may participate in renal CaOx stone progression and that allicin, together with its analogues, could be potential drugs for renal calculus precaution.

Peroxisome proliferator-activated receptor γ modulates renal crystal retention associated with high oxalate concentration by regulating tubular epithelial cellular transdifferentiation.

The differentiated phenotype of renal tubular epithelial cell exerts significant effect on crystal adherence. Peroxisome proliferator-activated receptor γ (PPARγ) has been shown to be critical for the regulation of cell transdifferentiation in many physiological and pathological conditions; however, little is known about its role in kidney stone formation. In the current study, we found that temporarily high oxalate concentration significantly decreased PPARγ expression, induced Madin Darby Canine Kidney cell dedifferentiation, and prompted subsequent calcium oxalate (CaOx) crystal adhesion in vitro. Furthermore, cell redifferentiation after the removal of the high oxalate concentration, along with a decreasing affinity to crystals, was an endogenic PPARγ-dependent process. In addition, the PPARγ antagonist GW9662, which can depress total-PPARγ expression and activity, enhanced cell dedifferentiation induced by high oxalate concentration and inhibited cell redifferentiation after removal of the high oxalate concentration. These effects were partially reversed by the PPARγ agonist 15d-PGJ2. Similar results were observed in animals that suffered from temporary hyperoxaluria followed by a recovery period. The active crystal-clearing process occurs through the transphenotypical morphology of renal tubular epithelial cells, reflecting cell transdifferentiation during the recovery period. However, GW9662 delayed cell redifferentiation and increased the secondary temporary crystalluria-induced crystal retention. This detrimental effect was partially reversed by 15d-PGJ2. Taken together, our results revealed that endogenic PPARγ activity plays a vital regulatory role in crystal clearance, subsequent crystal adherence, and CaOx stone formation via manipulating the transdifferentiation of renal tubular epithelial cells.