Attenuating Renal Interstitial Fibrosis by Shenqi Pill via Reducing Inflammation Response Regulated by NF-κB Pathway In Vitro and In Vivo.

INTRODUCTION: One of the most significant clinical features of chronic  kidney disease is renal interstitial fibrosis (RIF). This study aimed  to investigate the role and mechanism of Shenqi Pill (SQP) on RIF. METHODS: RIF model was established by conducting unilateral  ureteral obstruction (UUO) surgery on rat or stimulating human  kidney-2 (HK-2) cell with transforming growth factor ß1 (TGFß1).  After modeling, the rats in the SQP low dose group (SQP-L), SQP  middle dose group (SQP-M) and SQP high dose group (SQP-H)  were treated with SQP at 1.5, 3 or 6 g/kg/d, and the cells in the  TGFß1+SQP-L/M/H were treated with 2.5%, 5%, 10% SQP-containing  serum. In in vivo assays, serum creatinine (SCr) and blood urea  nitrogen (BUN) content were measured, kidney histopathology  was evaluated., and α-smooth muscle actin (α-SMA) expression  was detected by immunohistochemistry. Interleukin-1ß (IL-1ß),  interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) content,  inhibitor of kappa B alpha (IKBα) and P65 phosphorylation were  assessed. Meanwhile, cell viability, inflammatory cytokines content,  α-SMA expression, IKBα and P65 phosphorylation were detected  in vitro experiment.  Results. SQP exhibited reno-protective effect by decreasing SCr  and BUN content, improving renal interstitial damage, blunting  fibronectin (FN) and α-SMA expression in RIF rats. Similarly, after  the treatment with SQP-containing serum, viability and α-SMA  expression were remarkably decreased in TGFß1-stimulated HK-2  cell. Furthermore, SQP markedly down-regulated IL-1ß, IL-6, and  TNF-α content, IKBα and RelA (P65) phosphorylation both in vivo and in vitro.  Conclusion. SQP has a reno-protective effect against RIF in vivo and in vitro, and the effect is partly linked to nuclear factor-kappa  B (NF-κB) pathway related inflammatory response, which indicates  that SQP may be a candidate drug for RIF. DOI: 10.52547/ijkd.7546.

Ecliptasaponin A attenuates renal fibrosis by regulating the extracellular matrix of renal tubular cells.

Renal fibrosis is the most common manifestation of end-stage renal disease (ESRD), including diabetic kidney disease (DKD), but there is no effective treatment in renal fibrosis. Natural products are a rich source of clinical drug research and have been used in the clinical research of various diseases. In this study, we searched for traditional Chinese medicine monomers that attenuate fibrosis and assessed their effect on the fibrosis marker connective tissue growth factor (CTGF) in cells which we found ecliptasaponin A. Subsequently, we evaluated the effect of ecliptasaponin A on renal fibrosis in the classic renal fibrosis unilateral ureteral obstruction (UUO) mouse model and found that ecliptasaponin A could reduce the renal collagen fiber deposition and renal extracellular matrix (ECM) protein expression in UUO mice. In vitro, ecliptasaponin A can inhibit ECM protein expression in human kidney-2 (HK-2) cells induced by transforming growth factor-beta1 (TGFß1). To further clarify the mechanism of ecliptasaponin A in attenuating renal fibrosis, we performed transcriptome sequencing of HK-2 cells treated with TGFß1 and ecliptasaponin A. The functions and pathways were mainly enriched in the extracellular matrix and TGFß signalling pathway. Matrix metalloproteinase 10 (MMP10) and matrix metalloproteinase 13 (MMP13) are the main differentially expressed genes in extracellular matrix regulation. Then, we measured MMP10 and MMP13 in the cells and found that ecliptasaponin A had a significant inhibitory effect on MMP13 expression but not on MMP10 expression. Furthermore, we overexpressed MMP13 in HK-2 cells treated with TGFß1 and found that MMP13 promoted HK-2 cell injury. Our findings suggest that ecliptasaponin A can attenuate renal fibrosis, which may provide a new method for treating renal fibrosis clinically.

Myo-Inositol Attenuates Renal Interstitial Fibrosis in Obstructive Nephropathy by Inhibiting PI3K/AKT Activation.

Emerging evidence suggests that myo-inositol (MI) has a critical role in reducing renal inflammatory processes and improving podocyte function and preventing diabetes-related renal damage. We aimed to explore the function and underlying workings of MI in renal interstitial fibrosis (RIF). Based on a mouse model, we explored the effect of MI in unilateral ureteral obstruction (UUO) and in transforming growth factor-ß1 (TGF-ß1)-treated HK-2 cells. Pathological changes of the kidney tissues were examined following staining of the tissues with hematoxylin, eosin, and Masson's trichrome. The mRNA quantities of fibrosis markers, fibronectin, α-smooth muscle actin (α-SMA), and collagen I, were analyzed by means of real-time polymerase chain reaction, whereas those of protein levels were assessed with Western blotting. We also determined the expression of collagen I by immunofluorescence, and the levels of phosphorylated phosphotidylinositol-3-kinase and protein kinase B (PI3K/AKT) by Western blot. In vivo, histopathological examination in the UUO mice revealed renal tubular epithelial cell necrosis, inflammatory cell infiltration, and RIF. UUO mice showed higher expression levels of collagen I, fibronectin, α-SMA, pPI3K, and pAKT compared with sham-operated mice. However, MI treatment diminished the pathological alterations of RIF in UUO mice and downregulated the expression of fibrosis markers and phosphorylated PI3K/AKT. In vitro, TGF-ß1 positively influenced the propagation and differentiation of HK-2 cells and upregulated the levels of α-SMA, fibronectin, collagen I, pPI3K, and pAKT, but these became significantly reversed by MI treatment. In conclusion, MI ameliorates RIF, possibly by negatively regulating TGF-ß1-induced epithelial transdifferentiation and PI3K/AKT activation.

Qianjin Wenwu decoction suppresses renal interstitial fibrosis by enhancing the degradation of extracellular matrix in mice with unilateral ureteral obstruction.

Diabetic kidney disease (DKD) is the most common complication of diabetes mellitus (DM). Qianjin Wenwu decoction (QWD), a well-known traditional Korean medicine, has been used for the treatment of DKD, with satisfactory therapeutic effects. This study was designed to investigate the active components and mechanisms of action of QWD in the treatment of DKD. The results demonstrated that a total of 13 active components in five types were found in QWD, including flavonoids, flavonoid glycosides, phenylpropionic acids, saponins, coumarins, and lignins. Two key proteins, TGF-ß1 and TIMP-1, were identified as the target proteins through molecular docking. Furthermore, QWD significantly suppressed Scr and BUN levels which increased after unilateral ureteral obstruction (UUO). Hematoxylin & eosin (H&E) and Masson staining results demonstrated that QWD significantly alleviated renal interstitial fibrosis in UUO mice. We also found that QWD promoted ECM degradation by regulating MMP-9/TIMP-1 homeostasis to improve renal tubulointerstitial fibrosis and interfere with the expression and activity of TGF- ß1 in DKD treatment. These findings explain the underlying mechanism of QWD for the treatment of DKD, and also provide methodological reference for investigating the mechanism of traditional medicine in the treatment of DKD.

Podocarpusflavone alleviated renal fibrosis in obstructive nephropathy by inhibiting Fyn/Stat3 signaling pathway.

Tubulointerstitial fibrosis is a common pathological change in end-stage renal disease. However, limited treatment methods are developed, and unexplained potential mechanisms of renal diseases are urgent problems to be solved. In the present research, we first elucidated the role of podocarpusflavone (POD), a biflavone compound, in unilateral ureteral obstruction (UUO) in rodent model which is characterized by inflammation and fibrosis. The changes in histology and immunohistochemistry were observed that POD exerted renoprotective effects by retarding the infiltration of macrophage and aberrant deposition of ɑ-SMA, Col1a1, and fibronectin. Consistent with in vivo assay, POD treatment also ameliorated the process of fibrosis in TGF-ß1-stimulated renal tubular epithelial cells and inflammation in LPS-induced RAW264.7 cells in vitro. In terms of mechanism, our results showed that treatment with POD inhibited the aggravated activation of Fyn in the UUO group, and weakened the level of phosphorylation of Stat3 which indicated that POD may alleviate the process of fibrosis by the Fyn/Stat3 signaling pathway. Furthermore, the gain of function assay by lentivirus-mediated exogenous forced expression of Fyn abrogated the therapeutic effect of the POD on renal fibrosis and inflammation. Collectively, it can be concluded that POD exerted a protective effect on renal fibrosis by mediating Fyn/Stat3 signaling pathway.

Mechanism of dioscin ameliorating renal fibrosis through NF­κB signaling pathway­mediated inflammatory response.

Dioscin (DIS) is a natural compound derived from Chinese herbal medicine. In recent years, multiple studies have reported that DIS has immunoregulation, anti­fibrosis, anti­inflammation, anti­viral and anti­tumor effects. However, the mechanism by which DIS ameliorates renal fibrosis and inflammation remains to be elucidated. The aim of the present study was to investigate the role of DIS in renal fibrosis and inflammation and to explore its underlying mechanism. It used network pharmacology to predict the targets of DIS for the treatment of renal interstitial fibrosis. The present study was performed using unilateral ureteral obstruction mice and HK­2 cells in vivo and in vitro. The mice were treated with different doses of DIS. Kidney tissues were collected for histopathology staining, western blotting, immunohistochemistry staining and reverse transcription­quantitative (RT­q) PCR. TGF­ß1 (2 ng/ml) was used to induce renal fibrosis in the cells. Then, cells were respectively treated with DIS (3.125, 6.25, 12.5 µM) and Bay11­7082 (an inhibitor of NF­κB p65 nuclear transcription, 1 µM) for another 24 h. The expressions of inflammatory factors and NF­κB pathway proteins were detected by immunofluorescence, ELISA, western blotting and RT­qPCR. DIS alleviated renal injury in the UUO mice. Mechanistically, DIS not only decreased the expressions of inflammatory factors including IL­1ß, NOD­like receptor thermal protein domain associated protein 3, monocyte chemotactic protein 1, IL­6, TNF­α and IL­18 but also reduced the level of phosphorylation of NF­κB p65 in vivo and in vitro, which was similar to the impact of Bay11­7082. DIS ameliorated renal fibrosis by inhibiting the NF­κB signaling pathway­mediated inflammatory response, which may be a therapeutic pathway for delaying chronic kidney disease.

Rheum officinale and Salvia miltiorrhiza inhibit renal fibrosis via miR-21/PTEN/Akt signaling pathway in vitro and in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: As one of the main components of many famous Chinese herbal formulas, Rheum palmatum L. and Salvia miltiorhiza Bunge (RS) are extensively used to treat chronic kidney disease (CKD). RS has been proved to improve renal function and relieve renal fibrosis (RF), but the potential mechanism remains a mystery. AIM OF THE STUDY: The purpose of this study is to determine whether microRNA-21 (miR-21) is associated with RF progression, as well as whether RS protects against RF through miR-21/PTEN/AKT signaling. MATERIALS AND METHODS: (1) The rat model of RF was established using unilateral ureteral obstruction (UUO). After UUO surgery, miR-21 levels in plasma were detected by RT-PCR and RF scores were assessed by Masson's trichrome stain at days 3, 7, 14 and 21. The correlation analysis of the above two indexes was carried out by Spearman correlation analysis. (2) Human proximal tubular epithelial cells (HK-2) was transfected with miR-21 mimic and inhibitor, and then the levels of phosphatase and tensin homolog (PTEN) protein and mRNA were measured with Western blotting and RT-PCR, respectively. (3) TGF-ß (10 ng/mL) was added into HK-2 cells to induce fibrosis, followed by the intervention of RS-containing rat serum. PTEN and protein kinase-B (Akt) phosphorylation, as well as the expression of PTEN protein in HK-2 cells, were assessed by RT-PCR, Western blotting and immunofluorescence. (4) The rat models of RF were prepared by UUO and treated with RS. Serum creatinine and urea nitrogen levels were measured. RF score was determined by Masson's trichrome stain. RT-PCR was used to determine the expression of miR-21, PTEN, and Akt mRNA. Western blotting was used to determine the expression of PTEN and Akt proteins. RESULTS: A positive correlation was found between plasma miR-21 levels and RF scores of rats after UUO surgery at Days 3, 7, 14 and 21. It was confirmed that miR-21 targeted PTEN. RS drug-containing serum could rise the expression of PTEN and reduce Akt phosphorylation of HK-2 cells induced by TGF-ß. Moreover, RS drug-containing serum could increase PTEN expression and reduce Akt phosphorylation induced by miR-21 mimic in HK-2 cells. The rats treated with RS had significantly decreased serum creatinine and urea nitrogen levels and a lower RF score. RS also decreased miR-21 and Akt expressions, increased PTEN expression of UUO rats. CONCLUSION: There was a positive correlation between plasma miR-21 levels and RF scores. The inhibitory effect of RS on RF might be mediated by miR-21/PTEN/AKT signaling.

Quercetin inhibits the amphiregulin/EGFR signaling-mediated renal tubular epithelial-mesenchymal transition and renal fibrosis in obstructive nephropathy.

Quercetin is a widely distributed, bioactive flavonoid compound, which displays potential to inhibit fibrosis in several diseases. The purpose of our study was to determine the effect of quercetin treatment on renal fibrosis and investigate the mechanism. Human proximal tubular epithelial cells (HK-2) stimulated by transforming growth factor-ß1 (TGF-ß1) and a rat model of unilateral ureter obstruction (UUO) that contributes to fibrosis were used to investigate the role and molecular mechanism of quercetin. PD153035 (N-[3-Bromophenyl]-6,7-dimethoxyquinazolin-4-amine) was used to inactivate EGFR (epidermal growth factor receptor). The level of fibrosis, proliferation, apoptosis, and oxidative stress in HK-2 were measured. All data are presented as means ± standard deviation (SD). p-value < .05 was considered statistically significant. In UUO rats, quercetin reduced the area of fibrosis as well as inflammation, oxidative stress, and cell apoptosis. In cultured HK-2 cells, quercetin significantly ameliorated the EMT induced by TGF-ß1, which was accompanied by increased amphiregulin (AREG) expression. Moreover, quercetin inhibited AREG binding to the EGFR receptor, thereby further affecting other downstream pathways. Quercetin may alleviate fibrosis in vitro and in vivo by inhibiting the activation of AREG/EGFR signaling indicating a potential therapeutic effect of quercetin in renal fibrosis.

Yiqi Huoxue Tongluo recipe regulates NR4A1 to improve renal mitochondrial function in unilateral ureteral obstruction (UUO) rats.

CONTEXT: Yiqi Huoxue Tongluo recipe (YHTR) is a traditional Chinese medicine for the treatment of chronic kidney disease, but its exact mechanism is not clear. OBJECTIVES: To monitor the potential improvement of renal mitochondrial function in unilateral ureteral obstruction (UUO) rats by regulating NR4A1 using the YHTR. MATERIALS AND METHODS: Wistar rats were randomly divided into four groups: sham, UUO (left ureteral ligation for 14 days), eplerenone (EPL) (UUO + EPL), and YHTR (UUO + YHTR). UUO rats were established and intragastrically administered EPL (100 mg/day/kg) or YHTR (11.7 g/day/kg) for 14 days. The expression of related proteins in kidneys was detected by immunohistochemistry, western blot, RT-PCR, and chemical colorimetric assay, respectively. RESULTS: In vivo, YHTR treatment reduced the levels of BUN and Scr (by 17.9% and 23.5%) in UUO rats. Moreover, YHTR improved the renal mitochondrial function via increasing key enzymes of the tricarboxylic acid (TCA) cycle (p < 0.05) and activity of the mitochondrial complex (I-V) (by 30.8%, 29.1%, 19.7%, 35.9%, and 22.4%) in UUO rats. Compared with the UUO group, the expression of NR4A1 and Bcl-2 were significantly increased (p < 0.05), the expression of caspase-3 and caspase-9 were significantly decreased (p < 0.05) in the YHTR group. YHTR could upregulate key enzymes of the TCA cycle via promoting NR4A1 expression in HK2 cells, leading to inhibition of TGF-ß1 induced cell apoptosis. CONCLUSIONS: YHTR significantly improved the development of CKD; this study may provide new ideas for the pathogenesis of CKD and new strategies for the development of new drugs against CKD.

Isoandrographolide from Andrographis paniculata ameliorates tubulointerstitial fibrosis in ureteral obstruction-induced mice, associated with negatively regulating AKT/GSK-3ß/ß-cat signaling pathway.

Tubulointerstitial fibrosis (TIF) is a prominent pathological manifestation for the progression of almost all chronic kidney diseases (CKDs) to end-stage renal failure. However, there exist few efficient therapies to cure TIF. Our recent results showed that (8R, 12S)-isoandrographolide (ISA), a diterpenoid lactone ingredient of traditional Chinese herbal Andrographis paniculata (Burm.f.) Nees, exhibited anti-pulmonary fibrosis in silica-induced mice. Herein, we investigated the therapeutic effect of ISA on TIF, using mice subjected to unilateral ureteral obstruction (UUO) and human kidney proximal tubular epithelial (HK-2) cells treated with transforming growth factor-ß1 (TGF-ß1) or tumor necrosis factor-α (TNF-α). The pathological changes and collagen deposition results displayed that ISA administration significantly attenuated inflammatory response, ameliorated TIF, and protected the kidney injury. Interestingly, ISA revealed much lower cytotoxicity on HK-2 cells, but exhibited stronger inhibitory effect on tubular epithelial mesenchymal transformation (EMT) and inflammation, as compared to andrographolide (AD), the major ingredient of A. paniculata extract that has been reported to ameliorate TIF in diabetic nephropathy mice. It was further clarified that the amelioration of TIF by ISA was associated with suppressing the aberrant activation of AKT/GSK-3ß/ß-catenin pathway through network pharmacology analysis and experimental validation. Taken together, these findings indicate that ISA is a promising lead compound for development of anti-TIF, and even broad-spectrum anti-fibrotic drugs.

Deoxycholic acid-chitosan coated liposomes combined with in situ colonic gel enhances renal fibrosis therapy of emodin.

BACKGROUND: Renal fibrosis is the final common pathological feature of various chronic kidney diseases (CKD). Despite recent advances, development of new treatments strategy is needed. Emodin (EMO), an important ingredient of Chinese medicine, rhubarb (Polygonaceae Rheum palmatum l.), has been reported to inhibit the development of renal fibrosis effectively. However, the poor oral bioavailability of EMO and the insufficient monotherapy therapy compromise its efficacy. PURPOSE: In order to enhance renal fibrosis therapy of emodin, an innovative combination therapy based on deoxycholic acid-chitosan coated liposomes (DCS-Lips) and in situ colonic gel (IGE) was developed. METHODS: For one, the DCS-Lips were prepared via electrostatic interaction by mixing anionic conventional Lips with cationic DCS, deoxycholic acid conjugated on the backbone of chitosan. The cellular uptake of FITC-labeled DCS-Lips in Caco-2 cell monolayer was evaluated by CLSM and flow cytometry, respectively. Permeability study was carried out using Caco-2 cell monolayer. For another, EMO-loaded in situ colonic gel (EMO-IGE) was prepared by mixing EMO nanosuspensions and plain in situ gel, which was obtained by the cold method. The EMO-IGE was assessed for morphology, gelation temperature, viscosity and in vitro drug release. Finally, the therapeutic efficacy of the combination strategy, oral DCS-Lips formulations and in situ colonic gel, was evaluated in unilateral ureteral obstruction (UUO) rat model. Additionally, 16S rDNA sequencing was performed on rats faces to investigate whether the combination strategy improves the microbial dysbiosis in UUO rats. RESULTS: The prepared DCS-Lips produced small, uniformly sized nanoparticles, and significantly enhanced the cellular uptake and in vitro permeability of EMO compared to non-coated liposomes. Moreover, the EMO-IGE was characterized by short gelation time, optimal gelling temperature, and excellent viscosity. In UUO model, the combination of DCS-Lips (gavage) and IGE (enema) attenuated renal fibrosis effectively. The results of 16S rDNA sequencing illustrated that IGE could restore the gut microbial dysbiosis of UUO rats. CONCLUSION: Overall, the combination of DCS-Lips and EMO-IGE alleviated renal fibrosis effectively, resulting from the improved oral bioavailability of EMO by DCS-Lips and the restoration of gut microbiota by EMO-IGE, thus, presenting an innovative and promising potential for renal fibrosis treatment.

Delivery of sorafenib by myofibroblast-targeted nanoparticles for the treatment of renal fibrosis.

Fibrosis is an excessive accumulation of the extracellular matrix within solid organs in response to injury and a common pathway that leads functional failure. No clinically approved agent is available to reverse or even prevent this process. Herein, we report a nanotechnology-based approach that utilizes a drug carrier to deliver a therapeutic cargo specifically to fibrotic kidneys, thereby improving the antifibrotic effect of the drug and reducing systemic toxicity. We first adopted in vitro-in vivo combinatorial phage display technology to identify peptide ligands that target myofibroblasts in mouse unilateral ureteral obstruction (UUO)-induced fibrotic kidneys. We then engineered lipid-coated poly(lactic-co-glycolic acid) nanoparticles (NPs) with fibrotic kidney-homing peptides on the surface and sorafenib, a potent antineoplastic multikinase inhibitor, encapsulated in the core. Sorafenib loaded in the myofibroblast-targeted NPs significantly reduced the infiltration of α-smooth muscle actin-expressing myofibroblasts and deposition of collagen I in UUO-treated kidneys and enhanced renal plasma flow measured by Technetium-99m mercaptoacetyltriglycine scintigraphy. This study demonstrates the therapeutic potential of the newly identified peptide fragments as anchors to target myofibroblasts and represents a strategic advance for selective delivery of sorafenib to treat renal fibrosis. SIGNIFICANCE STATEMENT: Renal fibrosis is a pathological feature accounting for the majority of issues in chronic kidney disease (CKD), which may progress to end-stage renal disease (ESRD). This manuscript describes a myofibroblast-targeting drug delivery system modified with phage-displayed fibrotic kidney-homing peptides. By loading the myofibroblast-targeting nanoparticles (NPs) with sorafenib, a multikinase inhibitor, the NPs could suppress collagen synthesis in cultured human myofibroblasts. When given intravenously to mice with UUO-induced renal fibrosis, sorafenib loaded in myofibroblast-targeting NPs significantly ameliorated renal fibrosis. This approach provides an efficient therapeutic option to renal fibrosis. The myofibroblast-targeting peptide ligands and nanoscale drug carriers may be translated into clinical application in the future.

Yishen Huoxue decoction attenuates unilateral ureteric obstruction-induced renal fibrosis and hypoxia-induced reactive oxygen species generation via adenosine monophosphate-activated protein kinase / peroxisome proliferator-activated receptor coactivator-1α / silent mating-type information regulation 2 homolog 3 pathway.

OBJECTIVE: To investigate the effeicacy of Yishen Huoxue decoction (YSHX) on renal fibrosis induced by unilateral ureteric obstruction (UUO), and on reactive oxygen species (ROS) homeostasis in human umbilical vein endothelial cells (HUVECs). METHODS: Forty male mice were randomly divided into six groups, sham group, UUO group, UUO+ resveratrol (RSV) (15 mg/kg) group, UUO + YSHX 20 mg/kg group (UUO + YSHX-L), UUO + YSHX 40 mg/kg group (UUO + YSHX-M), UUO + YSHX 80 mg/kg group (UUO + YSHX-H). Western blotting was used to measure protein expression levels. Reverse transcription-quantitative polymerase chain reaction was used to measure the mRNA expression. Immunohistochemistry was used to examine the histopathological changes of kidney tissue sample. Cell apoptosis was measured by Annexin V/PI staining. Cell viability was measured using CCK-8/WST-8 assay. RESULTS: YSHX treatment reduced α-SMA and Col-4 expressions, and increased CD31 and VE-cadherin expressions in UUO model mice. In vitro, YSHX increased cell viability and decreased apoptosis of HUVECs under hypoxic conditions. YSHX inhibited ROS generation by activating adenosine monophosphate-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor coactivator-1α (PGC-1α)/silent mating-type information regulation 2 homolog 3 (Sirt3) signaling. CONCLUSION: YSHX treatment reduced 109KJ UUO-induced renal injury and fibrosis. Furthermore, YSHX treatment attenuated hypoxia-induced oxidative stress by regulating AMPK/PGC-1α/Sirt3 signaling.

Curcumin mediates repulsive guidance molecule B (RGMb) in the treatment mechanism of renal fibrosis induced by unilateral ureteral obstruction.

In this study, we explored the role and mechanism of repulsive guidance molecule B (RGMb, also known as Dragon) in the protective effects of curcumin against renal fibrosis and verified Dragon's effect on renal tubular epithelial cell apoptosis and cell programmability. Unilateral ureteral obstruction (UUO) was surgically induced in rats to establish a model of renal interstitial fibrosis (RIF). The rats were then treated with curcumin. Curcumin prominently decreased the serum creatinine (SCr) and blood urea nitrogen (BUN) levels, and also improved the tubular injury in the UUO-induced rats. Curcumin significantly downregulated the TGF-ß1, P-Smad2/3, cleaved caspase-3, cleaved caspase-8 and Dragon levels. Dragon knockdown also markedly reduced the TGF-ß1, P-Smad2/3, Smad2/3, cleaved caspase-3, cleaved caspase-8, fibronectin, collagen I, collagen IV, vimentin, and α-SMA expression levels. Conversely, Dragon overexpression caused higher expression levels of these proteins, and curcumin reversed this effect. Furthermore, Dragon knockdown increased the E-cadherin levels, whereas Dragon overexpression decreased these levels. Overexpressing Dragon significantly decreased the cell viability, and curcumin reversed this effect. In conclusion, curcumin acted on Dragon and attenuated RIF in UUO rat models. Curcumin downregulated the TGF-ß1/Smad signaling pathway and inhibited Dragon and fibrogenic molecules in both rats and HK-2 cells.

Emodin ameliorates tubulointerstitial fibrosis in obstructed kidneys by inhibiting EZH2.

Emodin, a major component of Chinese herbal rhubarb, delays the progression of chronic renal failure. However, the effect and working mechanisms of Emodin on renal tubulointerstitial fibrosis remains elusive. We hypothesized that emodin inhibits renal tubulointerstitial fibrosis through EZH2, a histone methyltransferase. Our in vivo and in vitro studies demonstrate that emodin reduced extracellular collagen deposition and inhibited Smad3 and CTGF pro-fibrotic signaling pathways, which were correlated with the down-regulation of EZH2 and reduced trimethylation of histone H3 on lysine 27 (H3k27me3) in NRK-49F fibrotic cells and UUO kidneys. Inhibition of EZH2 by 3-DZNeP blocked or attenuated the anti-fibrotic effect of emodin in UUO kidneys and NRK-49F cells. These data indicate that emodin inhibits renal tubulointerstitial fibrosis in obstructed kidneys and this effect is mediated through EZH2.

Effects of Shendibushen on the Expression of CD146 and its Metabolic Pathways.

Context: Evidence from multiple studies has revealed that it's meaningful to evaluate the clinical significance of CD146 because it's related to an early diagnosis of chronic renal failure as well as to the severity of illness and the patient's prognosis. Objective: The current study intended to evaluate the therapeutic effects of Shendibushen on the clinical parameters of blood and urine and on fibrosis in the kidney in a rat model, using simulated renal tissue fibrosis that was surgically induced with unilateral ureteral obstruction (UUO). Also, our research team intended to analyze the metabolic pathway activated by Shendibushen both in rat and human kidneys through use of the Kyoto Encyclopedia of Genes and Genomes (KEGG) database and the GeneNetwork. The aim is to discover if a connection existed between CD146 and key genes in these pathways. Design: The research team conducted an animal study in Wistar rats. Intervention: The rats were divided into 5 groups of 14 animals each: (1) blank control group, (2) sham control group, (3) model group, (4) Niaoduqing group, and (5) Shendibushen group. Three groups had UUO surgically induced-the model, Niaoduqing, and Shendibushen groups. The sham control group received sham surgery, and the blank control group received no surgery. The Shendibushen and Niaoduqing groups received the relevant capsules once a day at a fixed time, for a total of 28 days. Outcome Measures: The levels of serum creatinine, blood urea nitrogen, microalbuminuria, serum soluble CD146, and urinary soluble CD146 were measured on the 14th and 28th days after modeling the rats. The degree of renal interstitial fibrosis was examined by hematoxylin and eosin (HE) staining and Masson trichrome staining. The changes at transcriptome level were obtained by target tissue sequencing. The KEGG database was used to analyze the potential pathway activated by the Shendibushen treatment. The GeneNetwork analysis was used to validate the correlation and identify the connections between CD146 and the key genes of the potential pathways. Results: Shendibushen capsules decreased the degree of renal interstitial fibrosis in the UUO rat model and reduced the serum creatinine, blood urea nitrogen, microalbumin, serum sCD146, and urinary sCD146 significantly compared to the model group (P < .05). Upon analysis of the metabolic pathways activated by Shendibushen, the study further verified, through use of the KEGG database, that CD146 activated the nuclear factor kappa B1 (NF-κB1) and transforming growth factor beta 1 (TGF-ß1)/ SMAD family member 2 (SMAD2) pathways. Conclusions: CD146 could become an early indicator in clinical monitoring. CD146 has a function related to the NF-κB1and TGF-ß1/ SMAD2 pathways under Shendibushen treatment.

Pterostilbene, a Bioactive Component of Blueberries, Alleviates Renal Interstitial Fibrosis by Inhibiting Macrophage-Myofibroblast Transition.

Pterostilbene (PTB) is a derivative of resveratrol present in grapes and blueberries. PTB is structurally similar to resveratrol, possessing properties such as being analgesic, anti-aging, antidiabetic, anti-inflammatory, anti-obesity, anti-oxidation, cholesterol-reductive, and neuroprotective. However, there have not been reports on the effect of PTB on macrophage-myofibroblast transition (MMT) induced fibrosis in kidney. In this study, we investigated the antifibrotic effects of PTB on the in vivo mouse unilateral ureteral obstruction (UUO) model and in vitro MMT cells. Kidneys subjected to UUO with PTB treatment were collected for the investigation of PTB mediating MMT derived renal interstitial fibrosis. We conducted kidney RNA-seq transcriptomes and TGF-[Formula: see text]1-induced bone marrow-derived macrophages assays to determine the mechanisms of PTB. We found that PTB treatment suppressed the interstitial fibrosis in UUO mice. PTB also attenuated the number of MMT cells in vivo and in vitro. The transcriptomic analysis showed that CXCL10 may play a central role in the process of PTB-treated renal fibrosis. The siRNA-mediated CXCL10 knockdown decreased the number of MMT cells in TGF-[Formula: see text]1-induced bone marrow-derived macrophages. Our results suggested that PTB attenuated renal interstitial fibrosis by mediating MMT by regulating transcriptional activity of CXCL10.

Novel poricoic acids attenuate renal fibrosis through regulating redox signalling and aryl hydrocarbon receptor activation.

BACKGROUND: Renal fibrosis is the final manifestation of chronic kidney disease (CKD). Renal fibrosis is largely driven by oxidative stress and inflammation. PURPOSE: The aim of the current study was to identify novel poricoic acids from Poria cocos and investigated their antifibrotic effects and the underlying mechanism. METHODS: In this study, we identified six novel poricoic acids from Poria cocos and examined their antifibrotic effect using transforming growth factor-ß1- (TGF-ß1-) induced cultured human kidney proximal tubular epithelial cells (HK-2) and mice with unilateral ureteral obstruction (UUO). RESULTS: Treatment with six poricoic acids significantly inhibited TGF-ß1-induced α-smooth muscle actin expression at both mRNA and protein levels in HK-2 cells. Three compounds with an intact carboxyl group at C-3 position showed a stronger inhibitory effect than that of other three compounds with esterified carboxyl group at the C-3 position. Mechanistically, poricoic acid ZM (PZM) and poricoic acid ZP (PZP) attenuate renal fibrosis through the modulation of redox signalling including the inhibition of proinflammatory nuclear factor kappa B (NF-κB) signalling and its target genes as well as the activation of antioxidative nuclear factor-erythroid-2-related factor 2 (Nrf2) signalling and its downstream target gene in both TGF-ß1-induced HK-2 cells and UUO mice. PZM treatment and PZP treatment inhibit the upregulated aryl hydrocarbon receptor and they target the gene expression in UUO mice. Intriguingly, PZM treatment exhibits a stronger inhibitory effect than that of the PZP treatment. Structure-function relationship reveals that the carboxyl group at C-3 position is the most important bioactive function group in secolanostane tetracyclic triterpenoids against renal fibrosis. CONCLUSIONS: PZM and PZP attenuated renal fibrosis through the modulation of redox signalling and the aryl hydrocarbon receptor signalling pathway. Our findings will provide several promising leading compounds against renal fibrosis.

Shenkang VII Recipe Attenuates Unilateral Ureteral Obstruction-induced Renal Fibrosis via TGF-ß/Smad, NF-κB and SHH Signaling Pathway.

This study aimed to explore the protective effects of the traditional Chinese Medicine formula Shenkang VII recipe (SK-7) on renal fibrosis and the mechanisms. Renal fibrosis was induced by unilateral ureteral obstruction (UUO) in rats. The rats were then divided into 5 groups: control group (Sham operation), UUO model group, UUO model plus low to high doses of SK-7 (0.5, 1.0, or 2.0 g/kg/day, for 14 days) groups. The animals were sacrificed on the 7th or 14th day. Kidney tissues were collected for histopathological examinations (hematoxylin and eosin and Masson's trichrome staining). Immunohistochemistry was used to detect the expression of collagen type III (Col III), fibronectin (FN), α-smooth muscle actin (α-SMA), TIMP metallopeptidase inhibitor 2 (TIMP2), matrix metallopeptidase 2 (MMP2), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and monocyte chemotactic protein-1 (MCP-1). The TGF-ß1/Smad, NF-kB and Sonic hedgehog signaling proteins were detected by Western blotting. Our results showed that SK-7 prevented UUO-induced renal injury and accumulation of collagen fibrils. Renal fibrosis biomarkers Col III, FN, α-SMA and TIMP2 were increased in the rats after UUO and decreased by SK-7, while MMP2 was upregulated after treatment. SK-7 also suppressed the levels of TNF-α, IL-1ß and MCP-1 in UUO rats. In addition, SK-7 inhibited activation of the TGF-ß/Smad, NF-κB and sonic hedgehog signaling (SHH) pathways. Taken together, these findings suggest that SK-7 may regulate the synthesis and degradation of extracellular matrix, reduce inflammation and suppress the proliferation of fibroblasts, by blocking the TGF-ß1/Smad, NF-κB and SHH signaling pathways to exert its anti-renal fibrosis effect in UUO rats.