Ultra performance liquid chromatography-based metabonomic study of therapeutic effect of the surface layer of Poria cocos on adenine-induced chronic kidney disease provides new insight into anti-fibrosis mechanism

Poria cocos: traditional uses, triterpenoid components and their renoprotective pharmacology

Poria cocos and its surface layer of Poria cocos (Schw.) Wolf (Polyporaceae), are used in traditional Chinese medicine for its diuretic and renoprotective effects. Phytochemical studies have shown that lanostane and 3,4-seco-lanostane tetracyclic triterpenoids are the main components of P. cocos and its surface layer. Accumulating evidence shows that triterpenoid components in P. cocos and its surface layer contribute to their renoprotective effect. The surface layer of P. cocos showed a stronger diuretic effect than P. cocos. The ethanol extract of the surface layer and its components improved acute kidney injury, acute kidney injury-to-chronic kidney disease transition and chronic kidney disease such as diabetic kidney disease, nephrotic syndrome and tubulointerstitial nephropathy, and protected against renal fibrosis. It has been elucidated that P. cocos and its surface layer exert a diuretic effect and improve kidney diseases through a variety of molecular mechanisms such as aberrant pathways TGF-β1/Smad, Wnt/β-catenin, IκB/NF-κB and Keap1/Nrf2 signaling as well as the activation of renin-angiotensin system, matrix metalloproteinases, aryl hydrocarbon receptor and endogenous metabolites. These studies further confirm the renoprotective effect of P. cocos and its surface layer and provide a beneficial basis to its clinical use in traditional medicine.

The potential molecular mechanism underlying gypenoside amelioration of atherosclerosis in ApoE-/- mice: A multi-omics investigation

Gypenosides (Gyp) are bioactive components of Gynostemma pentaphyllum that have a variety of pharmacological properties. Extracts of G. pentaphyllum have been found to be effective in the reduction of blood sugar and lipids and prevention of atherosclerosis. Here, the functions of Gyp and the mechanisms underlying their effects on atherosclerosis were investigated. Mice were allocated to three groups, namely, the control (C57BL/6), atherosclerosis model (ApoE-/- mice with high-fat diet), and Gyp-treated groups. Differentially expressed mRNAs, miRNAs, circRNA, and differential metabolites among the groups were analyzed. The results showed that "Fatty acid metabolism", "Fatty acid elongation", "Cytokine-cytokine receptor interaction", and "PI3K-Akt signaling pathway", amongst others, were involved in treatment process. Differentially expressed genes, including Fabp1, Apoe, FADS1, ADH1, SYNPO2, and Lmod1were also identified. Mmu-miR-30a and mmu-miR-30e showed reduced expression in atherosclerosis models but were increased following Gyp treatment, suggesting involvement in the effects of Gyp. In addition, chr5:150604177-150608440 were found to interact with mmu-miR-30a and mmu-miR-30e to regulate their abundance. In terms of metabolomics, Gyp may regulate biological processes involving PGD2 and PGJ2, potentially alleviating atherosclerosis. In conclusion, Gyp appeared to have complex effects on atherosclerosis, most of which were positive. These results support the use of Gyp in the treatment of atherosclerosis.

A curcumin oral delivery system based on sodium caseinate and carboxymethylpachymaran nanocomposites

The food industry has paid lots of attentions to curcumin because of its potential bioactive qualities. However, its use is severely constrained by its low bioavailability, stability and water solubility. Herein, we created sodium caseinate and carboxymethylpachymaran (CMP) nanoparticles (SMCNPs) that were loaded with curcumin. The composite nanoparticles were spherical, as characterized by SEM and TEM, the fluorescence spectroscopy, FTIR and XRD research revealed that hydrogen bonding, hydrophobic interaction and electrostatic interaction were the main drivers behind the creation of the nanoparticles. The SMCNPs exhibited lower particle size, greater dispersion and higher encapsulation rate when the mass ratio of sodium caseinate to CMP was 3:5 (particle size of 166.8 nm, PDI of 0.15, and encapsulation efficiency of 88.07 %). The composite nanoparticles had good antioxidant activity, physical stability and sustained release effect on intestinal tract during the in vitro simulation experiments, successfully preventing the early release of curcumin into gastric fluid. Finally, cytotoxicity studies told that the prepared composite nanoparticles have good biocompatibility and can inhibit the growth of tumor cells (HT-29). In conclusion, using CMP and sodium caseinate as carriers in this study may open up a fresh, environmentally friendly, and long-lasting way to construct a bioactive material delivery system.

Modified Zhibai Dihuang pill alleviated urinary tract infection induced by extended-spectrum β-lactamase Escherichia coli in rats by regulating biofilm formation

CONTEXT

Zhibai Dihuang pill (ZD), a traditional Chinese medicine nourishes Yin and reduces internal heat, is believed to have therapeutic effects on urinary tract infections (UTIs).

OBJECTIVE

To explore the effects and mechanism of modified ZD (MZD) on UTI induced by extended-spectrum β-lactamase (ESBLs) Escherichia coli.

MATERIALS AND METHODS

Thirty Sprague-Dawley rats were randomly divided into control, model (0.5 mL 1.5 × 108 CFU/mL ESBLs E. coli), MZD (20 g/kg MZD), LVFX (0.025 g/kg LVFX), and MZD + LVFX groups (20 g/kg MZD + 0.025 g/kg LVFX), n = 6. After 14 days of treatment, serum biochemical indicators, renal function indicators, bladder and renal histopathology, and urine bacterial counts in rats were determined. Additionally, the effects of MZD on ESBLs E. coli biofilm formation and related gene expression were analyzed.

RESULTS

MZD significantly decreased the count of white blood cells (from 13.12 to 9.13), the proportion of neutrophils (from 43.53 to 23.18), C-reactive protein (from 13.21 to 9.71), serum creatinine (from 35.78 to 30.15), and urea nitrogen (from 12.56 to 10.15), relieved the inflammation and fibrosis of bladder and kidney tissues, and reduced the number of bacteria in urine (from 2174 to 559). In addition, MZD inhibited the formation of ESBLs E. coli biofilms (2.04-fold) and decreased the gene expressions of luxS, pfS and ompA (1.41-1.62-fold).

DISCUSSION AND CONCLUSION

MZD treated ESBLs E. coli-induced UTI inhibited biofilm formation, providing a theoretical basis for the clinical application of MZD. Further study on the clinical effect of MZD may provide a novel therapy option for UTI.

The Protective Role of Ozone Therapy in Kidney Disease: A Review

Ozone (O3) is a reactive oxygen species (ROS) that can interact with cellular components and cause oxidative stress. Following said logic, if O3 induces such a stressful milieu, how does it exert antioxidant functions? This is mediated by controlled toxicity produced by low concentrations of O3, which enhance the cell’s suppliance of antioxidant properties without causing any further damage. Therapeutic concentrations vary extensively, although 50 µg/mL is commonly used in experimental and clinical procedures, given that augmented concentrations might work as germicides or cause endogenous damage. O3 therapy has been shown to be effective when applied before or after traumatic renal procedures, whether caused by ischemia, xenobiotics, chronic damage, or other models. In this review, we focus on discussing the role of O3 therapy in different models of kidney damage associated with fibrosis, apoptosis, oxidative stress, and inflammation. We integrate and report knowledge about O3 in renal therapy, debunking skepticism towards unconventional medicine, explaining its proven therapeutic properties, and thus providing background for its use in further research as well as in clinical settings.

TGF-β/Smad Signaling Pathway in Tubulointerstitial Fibrosis

Chronic kidney disease (CKD) was a major public health problem worldwide. Renal fibrosis, especially tubulointerstitial fibrosis, is final manifestation of CKD. Many studies have demonstrated that TGF-β/Smad signaling pathway plays a crucial role in renal fibrosis. Therefore, targeted inhibition of TGF-β/Smad signaling pathway can be used as a potential therapeutic measure for tubulointerstitial fibrosis. At present, a variety of targeting TGF-β1 and its downstream Smad proteins have attracted attention. Natural products used as potential therapeutic strategies for tubulointerstitial fibrosis have the characteristics of acting on multiple targets by multiple components and few side effects. With the continuous research and technique development, more and more molecular mechanisms of natural products have been revealed, and there are many natural products that inhibited tubulointerstitial fibrosis via TGF-β/Smad signaling pathway. This review summarized the role of TGF-β/Smad signaling pathway in tubulointerstitial fibrosis and natural products against tubulointerstitial fibrosis by targeting TGF-β/Smad signaling pathway. Additionally, many challenges and opportunities are presented for inhibiting renal fibrosis in the future.

Functional Analysis of Sterol O-Acyltransferase Involved in the Biosynthetic Pathway of Pachymic Acid in Wolfiporia cocos

Pachymic acid from Wolfiporia cocos possesses important medicinal values including anti-bacterial, anti-inflammatory, anti-viral, invigorating, anti-rejection, anti-tumor, and antioxidant activities. However, little is known about the biosynthetic pathway from lanostane to pachymic acid. In particular, the associated genes in the biosynthetic pathway have not been characterized, which limits the high-efficiency obtaining and application of pachymic acid. To characterize the synthetic pathway and genes involved in pachymic acid synthesis, in this study, we identified 11 triterpenoids in W. cocos using liquid chromatography tandem mass spectrometry (LC-MS/MS), and inferred the putative biosynthetic pathway from lanostane to pachymic acid based on analyzing the chemical structure of triterpenoids and the transcriptome data. In addition, we identified a key gene in the biosynthetic pathway encoding W. cocos sterol O-acyltransferase (WcSOAT), which catalyzes tumolusic acid to pachymic acid. The results show that silence of WcSOAT gene in W. cocos strain led to reduction of pachymic acid production, whereas overexpression of this gene increased pachymic acid production, indicating that WcSOAT is involved in pachymic acid synthesis in W. cocos and the biosynthesis of W. cocos pachymic acid is closely dependent on the expression of WcSOAT gene. In summary, the biosynthetic pathway of pachymic acid and the associated genes complement our knowledge on the biosynthesis of W. cocos pachymic acid and other triterpenoids, and also provides a reference for target genes modification for exploring high-efficiency obtaining of active components.

The synergic renoprotective effect of Rehmanniae Radix Preparata and Corni Fructus on adenine-induced chronic kidney disease rats based on integrated plasma metabolomics and network pharmacology approach

AIMS

Rehmanniae Radix Preparata (RR) and Corni Fructus (CF) are commonly used together for the treatment of chronic kidney disease (CKD) in the clinical practices for thousands of years. However, little information on their synergy mechanism is available.

MAIN METHODS

In this study, an integrated approach combining ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS)-based metabonomics and network pharmacology was adopted to elucidate the cooperation mechanism of RR and CF on the amelioration of CKD. Furthermore, the targets from network pharmacology and metabolism pathways were jointly analyzed. Finally, the activities of key metabolic enzymes were experimentally validated by ELISA.

KEY FINDINGS

Metabolic profiling indicated that the metabolic disturbance in plasma was markedly alleviated after treatment. Nine putative biomarkers mainly involving in phenylalanine, tyrosine and tryptophan biosynthesis and tyrosine metabolism were identified. Moreover, the compound-target-pathway network of RR and CF for CKD treatment was constructed by network pharmacology, which was related to tyrosine metabolism and arginine and proline metabolism. The results were partly consistent with the findings of plasma metabolomics.

SIGNIFICANCE

In conclusion, this study solidly supported and enhanced current understanding of the synergy effects of RR and CF on CKD. Meanwhile, it also confirmed the feasibility of combining metabolomics and network pharmacology to identify active components and elucidate the pharmacological effects of traditional Chinese medicines (TCMs).

Polyporus Umbellatus Protects Against Renal Fibrosis by Regulating Intrarenal Fatty Acyl Metabolites

Background: Chronic renal failure (CRF) results in significant dyslipidemia and profound changes in lipid metabolism. Polyporus umbellatus (PPU) has been shown to prevent kidney injury and subsequent kidney fibrosis.

Methods: Lipidomic analysis was performed to explore the intrarenal profile of lipid metabolites and further investigate the effect of PPU and its main bioactive component, ergone, on disorders of lipid metabolism in rats induced by adenine. Univariate and multivariate statistical analyses were performed for choosing intrarenal differential lipid species in CRF rats and the intervening effect of n-hexane extract of PPU and ergone on CRF rats.

Results: Compared with control group, decreased creatinine clearance rate indicated declining kidney function in CRF group. Based on the lipidomics, we identified 65 lipid species that showed significant differences between CRF and control groups. The levels of 12 lipid species, especially fatty acyl lipids including docosahexaenoic acid, docosapentaenoic acid (22n-3), 10,11-Dihydro-12R-hydroxy-leukotriene C4, 3-hydroxydodecanoyl carnitine, eicosapentaenoic acid, hypogeic acid and 3-hydroxypentadecanoic acid had a strong linear correlation with creatinine clearance rate, which indicated these lipid species were associated with impaired renal function. In addition, receiver operating characteristics analysis showed that 12 lipid species had high area under the curve values with high sensitivity and specificity for differentiating CRF group from control group. These changes are related to the perturbation of fatty acyl metabolism. Treatment with PPU and ergone improved the impaired kidney function and mitigated renal fibrosis. Both chemometrics and cluster analyses showed that rats treated by PPU and ergone could be separated from CRF rats by using 12 lipid species. Intriguingly, PPU treatment could restore the levels of 12 lipid species, while treatment with ergone could only reverse the changes of six fatty acids in CRF rats.

Conclusion: Altered intrarenal fatty acyl metabolites were implicated in pathogenesis of renal fibrosis. PPU and ergone administration alleviated renal fibrosis and partially improved fatty acyl metabolism. These findings suggest that PPU exerted its renoprotective effect by regulating fatty acyl metabolism as a potential biochemical mechanism. Therefore, these findings indicated that fatty acyl metabolism played an important role in renal fibrosis and could be considered as an effective therapeutic avenue against renal fibrosis.

Poricoic acid A suppresses TGF-β1-induced renal fibrosis and proliferation via the PDGF-C, Smad3 and MAPK pathways

Renal interstitial fibrosis is the most important pathological process in chronic renal failure. Previous studies have shown that poricoic acid A (PAA), the main chemical constituent on the surface layer of the mushroom Poria cocos, has protective effects against oxidative stress and acute kidney injury. The present study aimed to investigate the potential roles of PAA on the pathological process of renal fibrosis and the associated molecular mechanism. The NRK-49F cell line was treated with transforming growth factor-β1 (TGF-β1) with or without PAA or platelet-derived growth factor C (PDGF-C). Cell Counting Kit-8 assay, western blotting and 5-ethynyl-2'-deoxyuridine immunofluorescence staining were performed to examine cell growth, protein expression and cell proliferation, respectively. Data from the present study showed that 10 µM PAA attenuated TGF-β1-induced NRK-49F cell extracellular matrix (ECM) accumulation, fibrosis formation and proliferation. Renal fibrosis with the activation of Smad3 and mitogen-activated protein kinase (MAPK) pathways were also inhibited by PAA treatment. PDGF-C reversed the inhibitory effects of PAA on TGF-β1-induced renal fibroblast proliferation and activation of the Smad3/MAPK pathway. The present study suggested that suppression of TGF-β1-induced renal fibroblast ECM accumulation, fibrosis formation and proliferation by PAA is mediated via the inhibition of the PDGF-C, Smad3 and MAPK pathways. The present findings not only revealed the potential anti-fibrotic effects of PAA on renal fibroblasts, but also provided a new insight into the prevention of fibrosis formation via regulation of the PDGF-C, Smad3 and MAPK signaling pathways.

The influence of the prebiotic gum acacia on the intestinal microbiome composition in rats with experimental chronic kidney disease

Chronic kidney disease (CKD) is a globally common and important disease and there are evidence for a bidirectional relationship between microbiota and CKD. The aim of the study was to examine the influence of prebiotic - gum acacia (GA) on the intestinal microbiota in rats with adenine-induced CKD. Animals were randomly distributed into four equal groups (n = 6): control, adenine, GA and adenine + GA groups. CKD was induced by adenine (0.75% w/w) given in the diet daily for four weeks, and GA was administered in drinking water at a concentration of 15% w/v. The 16s rRNA analysis was performed on Illumina Miseq targeting V3-V4 region to characterize microbial composition. The abundance of Actinobacteria, Proteobacteria, Tenericutes and Verrucomicrobia bacteria was increased in adenine-induced CKD, and GA treatment successfully reversed those levels. Interestingly, alpha and beta diversity index were both reduced with GA treatment in rats with CKD. Short chain fatty acids (SCFAs) measurement and PICRUSt analysis have shown that GA treatment completely restored the depleted butyrate level and various perturbated functional pathways, respectively, in CKD rats. Taking together, our results suggest that GA supplementation has a beneficial role in treating CKD, through an increased production of butyrate, as well as its anti-inflammatory, antioxidant capacity and anti-nitrosative properties.

Poricoic acid A as a modulator of TPH-1 expression inhibits renal fibrosis via modulating protein stability of β-catenin and β-catenin-mediated transcription

Background

Renal fibrosis is the common feature of chronic kidney disease (CKD). However, few drugs specifically target fibrogenesis due to the lack of an effective therapeutic target. Hence, it is urgent to find a therapeutic strategy that inhibits renal fibrosis. Here, we identified that poricoic acid A (PAA) as the modulator of tryptophan hydroxylase-1 (TPH-1), the key enzyme in tryptophan metabolism, exerted potent anti-fibrotic effects in the kidney.

Methods

Lentiviral vector, luciferase reporter activity assay and co-immunoprecipitation were used. The animal model of unilateral ureteral obstruction and adenine-induced chronic renal failure as well as transforming growth factor (TGF)-β1-treated epithelial cells NRK-52E and fibroblasts NRK-49F were used.

Results

TPH-1 was gradually decreased during CKD progression, while PAA treatment significantly increased TPH-1 expression to suppress renal fibrosis. Pharmacological overexpression of TPH-1 by PAA treatment exhibited anti-fibrosis and was linked to Wnt/β-catenin signaling activity. TPH-1 exhibited anti-fibrotic effects by suppressing epithelial cell injury and fibroblast activation, and PAA promoted TPH-1 expression and then suppressed the Wnt/β-catenin signaling pathway via regulating the protein stability of β-catenin and β-catenin-mediated transcription. TPH-1 overexpression enhanced the anti-fibrotic effects of PAA, while TPH-1 deficiency weakened the anti-fibrotic effects of PAA, indicating that TPH-1 was required for the anti-fibrotic effects of PAA.

Conclusion

PAA as a modulator of TPH-1 expression attenuated renal fibrosis through regulating the Wnt/β-catenin signaling pathway by acting on the protein stability of β-catenin and β-catenin-mediated transcription. TPH-1 was required for PAA to exert anti-fibrosis.

Serum metabolomics approach to monitor the changes in metabolite profiles following renal transplantation

Systemic metabolic changes after renal transplantation reflect the key processes that are related to graft accommodation. In order to describe and better understand these changes, the ¹HNMR based metabolomics approach was used. The changes of 47 metabolites in the serum samples of 19 individuals were interpreted over time with respect to their levels prior to transplantation. Considering the specific repeated measures design of the experiments, data analysis was mainly focused on the multiple analyses of variance (ANOVA) methods such as ANOVA simultaneous component analysis and ANOVA-target projection. We also propose here the combined use of ANOVA and classification and regression trees (ANOVA-CART) under the assumption that a small set of metabolites the binary splits on which may better describe the graft accommodation processes over time. This assumption is very important for developing a medical protocol for evaluating a patient's health state. The results showed that besides creatinine, which is routinely used to monitor renal activity, the changes in levels of hippurate, mannitol and alanine may be associated with the changes in renal function during the post-transplantation recovery period. Specifically, the level of hippurate (or histidine) is more sensitive to any short-term changes in renal activity than creatinine.

Poricoic acid A activates AMPK to attenuate fibroblast activation and abnormal extracellular matrix remodelling in renal fibrosis

BACKGROUND

In chronic kidney disease, although fibrosis prevention is beneficial, few interventions are available that specifically target fibrogenesis. Poricoic acid A (PAA) isolated from Poria cocos exhibits anti-fibrotic effects in the kidney, however the underlying mechanisms remain obscure.

PURPOSE

We isolated PAA and investigated its effects and the underlying mechanisms in renal fibrosis.

STUDY DESIGN

Unilateral ureteral obstruction (UUO) and 5/6 nephrectomy (Nx) animal models and TGF-β1-induced renal fibroblasts (NRK-49F) were used to investigate the anti-fibrotic activity of PAA and its underlying mechanisms.

METHODS

Western blots, qRT-PCR, immunofluorescence staining, co-immunoprecipitation and molecular docking methods were used. Knock-down and knock-in of adenosine monophosphate-activated protein kinase (AMPK) in the UUO model and cultured NRK-49F cells were employed to verify the mechanisms of action of PAA.

RESULTS

PAA improved renal function and alleviated fibrosis by stimulating AMPK and inhibiting Smad3 specifically in Nx and UUO models. Reduced AMPK activity was associated with Smad3 induction, fibroblast activation, and the accumulation and aberrant remodelling of extracellular matrix (ECM) in human renal puncture samples and cultured NRK-49F cells. PAA stimulated AMPK activity and decreased fibrosis in a dose-dependent manner, thus showing that AMPK was essential for PAA to exert its anti-fibrotic effects. AMPK deficiency reduced the anti-fibrotic effects of PAA, while AMPK overexpression enhanced its effect.

CONCLUSION

PAA activated AMPK and further inhibited Smad3 specifically to suppress fibrosis by preventing aberrant ECM accumulation and remodelling and facilitating the deactivation of fibroblasts.

The role of Chinese herbal medicine in the management of adverse drug reactions of leflunomide in treating rheumatoid arthritis

BACKGROUND

The high discontinuation rate in RA patients who use LEF might be attributed to their intolerance rather than irresponsibility. The concomitant administration of Leflunomide (LEF) with Chinese herbal medicine (CHM) provides a potential solution to preventing the adverse drug reactions (ADRs) induced by LEF during the treatment of rheumatoid arthritis (RA).

PURPOSE

To investigate whether co-administration of LEF with CHM could bring in both increased therapeutic outcomes and reduced ADRs due to the framework of treatment at the level of entire body.

STUDY DESIGN

The mechanism of LEF in RA treatment and the ADRs it induced was introduced based on recent papers. Reported clinical examples of CHM concurrent use with LEF was revealed to provide more evidence. The management of the ADRs caused by LEF was suggested by current researches on the concomitant therapy of CHM with LEF.

RESULTS

The active ingredients, compounds and medicinal herbs all demonstrated properties in relieving toxicities and reducing ADRs when used with LEF and reported in several clinical cases. The wide application of concurrent use of CHM with LEF is however hindered by the complex pathogenesis of RA which requires further scientific grounds for diagnosis and treatment.

CONCLUSION

This review introduced that the adoption of CHM is emerging as a novel strategy for the management of ADRs caused by LEF.

Metabolic and transcriptional changes in seminal plasma of asthenozoospermia patients

This study was designed to investigate the metabolic and transcriptional alterations in seminal fluid caused by asthenozoospermia (AS). To address these issues, a method of metabonomics based on ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and real-time quantitative PCR (RT-qPCR) was performed to identify some crucial biomarkers and transcription levels of the enzymes in seminal fluid. Seminal fluid samples were collected from 87 AS patients and 73 healthy males with normozoospermia. The quantitative analysis by UPLC-MS/MS showed that 19 metabolites in seminal plasma were associated with AS, and they were involved in several metabolic pathways, such as energy metabolism, purine metabolism, methionine cycle, and branched chain amino acid metabolism. Among these metabolites, the levels of citric acid, malic acid, succinic acid, and pyruvic acid, which are related to energy metabolism, were collectively reduced in the AS group, whereas the lactic acid level was enhanced. These results indicated that lesser energy source (adenosine triphosphate) was produced through the anaerobic glycolysis pathway rather than via aerobic catabolism of suger and tricarboxylic acid cycle, resulting in reduced power of sperms. Meanwhile, partial least squares discriminant analysis showed significant differences in metabolic profiles between the AS and control groups. In addition, RT-qPCR results revealed that the expression levels of four genes encoding fructokinase citrate synthase, succinate dehydrogenase, and spermine synthase, which were related to energy metabolism, were decreased in the AS group. The 23 descriptors with differential expression in AS may be valuable for the diagnosis and sequential study on AS. These results will help highlight the role of sperm inactivity in AS pathogenesis.

Microbiome-metabolomics reveals gut microbiota associated with glycine-conjugated metabolites and polyamine metabolism in chronic kidney disease

Dysbiosis of the gut microbiome and related metabolites in chronic kidney disease (CKD) have been intimately associated with the prevalence of cardiovascular diseases. Unfortunately, thus far, there is a paucity of sufficient knowledge of gut microbiome and related metabolites on CKD progression partly due to the severely limited investigations. Using a 5/6 nephrectomized (NX) rat model, we carried out 16S rRNA sequence and untargeted metabolomic analyses to explore the relationship between colon's microbiota and serum metabolites. Marked decline in microbial diversity and richness was accompanied by significant changes in 291 serum metabolites, which were mediated by altered enzymatic activities and dysregulations of lipids, amino acids, bile acids and polyamines metabolisms. Interestingly, CCr was directly associated with some microbial genera and polyamine metabolism. However, SBP was directly related to certain microbial genera and glycine-conjugated metabolites in CKD rats. Administration of poricoic acid A (PAA) and Poria cocos (PC) ameliorated microbial dysbiosis as well as attenuated hypertension and renal fibrosis. In addition, treatments with PAA and PC lowered serum levels of microbial-derived products including glycine-conjugated compounds and polyamine metabolites. Collectively, the present study confirmed the CKD-associated gut microbial dysbiosis and identified a novel dietary and therapeutic strategy to improve the gut microbial dysbiosis and the associated metabolomic disorders and retarded the progression of kidney disease in the rat model of CKD.

Discrimination of Different Parts of Saffron by Metabolomic-Based Ultra-Performance Liquid Chromatography Coupled with High-Definition Mass Spectrometry

In this study, the metabolite profiling of three different parts of Crocus sativus L. was measured by using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTof-MS/MS). Multivariate statistical analysis was used to distinguish among the samples from different parts. A total of 54 compounds were identified in tepals, stigmas and stamens by UPLC-QTof-MS/MS. The results stated that chemical characteristics of saffron were obviously diverse in terms of the parts of flower. Through analysis, coniferin and crocin-2 were special components in stigmas when compared to tepals and stamens. The content of flavonoids was high in tepals when compared with the stigmas. The tepal of saffron may processed as a source of flavonoids in the future. The research provided the basis for the theory that only the stigma can be used as medicine.

Redox signaling in aging kidney and opportunity for therapeutic intervention through natural products

Kidney diseases are serious public problems with high morbidity and mortality in the general population and heavily retard renal function with aging regardless of the cause. Although myriad strategies have been assigned to prevent or harness disease progression, unfortunately, thus far, there is a paucity of effective therapies partly due to an insufficient knowledge of underlying pathological mechanisms, indicating deeper studies are urgently needed. Additionally, natural products are increasingly recognized as an alternative source for disease intervention owing to the potent safety and efficacy, which might be exploited for novel drug discovery. In this review, we primarily expatiate the new advances on mediators that might be amenable to targeting aging kidney and kidney diseases, including nicotinamide adenine dinucleotide phosphate oxidase (NOX), transforming growth factor-β (TGF-β), renin-angiotensin system (RAS), nuclear factor-erythroid 2 related factor 2 (Nrf2), peroxisome proliferator-activated γ receptor (PPARγ), advanced glycation endproducts (AGEs) as well as microRNAs and vitagenes. Of note, we conclude by highlighting some natural products which have the potential to facilitate the development of novel treatment for patients with myriad renal diseases.

Combined melatonin and poricoic acid A inhibits renal fibrosis through modulating the interaction of Smad3 and β-catenin pathway in AKI-to-CKD continuum

Background:

Acute kidney injury (AKI) is one of the major risk factors for progression to chronic kidney disease (CKD) and renal fibrosis. However, effective therapies remain poorly understood. Here, we examined the renoprotective effects of melatonin and poricoic acid A (PAA) isolated from the surface layer of Poria cocos, and investigated the effects of combined therapy on the interaction of TGF-β/Smad and Wnt/β-catenin in a rat model of renal ischemia-reperfusion injury (IRI) and hypoxia/reoxygenation (H/R) or TGF-β1-induced HK-2 cells.

Methods:

Western blot and immunohistochemical staining were used to examine protein expression, while qRT-PCR was used to examine mRNA expression. Coimmunoprecipitation, chromatin immunoprecipitation, RNA interference, and luciferase reporter gene analysis were employed to explore the mechanisms of PAA and melatonin’s renoprotective effects.

Results:

PAA and combined therapy exhibited renoprotective and antifibrotic effects, but the underlying mechanisms were different during AKI-to-CKD continuum. Melatonin suppressed Smad-dependent and Smad-independent pathways, while PAA selectively inhibited Smad3 phosphorylation through distrupting the interactions of Smad3 with TGFβRI and SARA. Further studies demonstrated that the inhibitory effects of melatonin and PAA were partially depended on Smad3, especially PAA. Melatonin and PAA also inhibited the Wnt/β-catenin pathway and its profibrotic downstream targets, and PAA performed better. We further determined that IRI induced a nuclear Smad3/β-catenin complex, while melatonin and PAA disturbed the interaction of Smad3 and β-catenin, and supplementing with PAA could enhance the inhibitory effects of melatonin on the TGF-β/Smad and Wnt/β-catenin pathways.

Conclusions:

Combined melatonin and PAA provides a promising therapeutic strategy to treat renal fibrosis during the AKI-to-CKD continuum.

The Matrix Metalloproteinase-13 Inhibitor Poricoic Acid ZI Ameliorates Renal Fibrosis by Mitigating Epithelial-Mesenchymal Transition

SCOPE

Fibrosis plays a key role in the progression of various diseases. Matrix metalloproteinases (MMPs) are important for epithelial-mesenchymal transition (EMT), which contributes to organ fibrosis. Four new poricoic acids are identified, poricoic acid ZI, ZJ, ZK, and ZL, as novel MMP inhibitors from edible mushroom Poria cocos.

METHODS

Molecular docking, siRNA techniques, TGF-β1-treated renal cells, and unilateral ureteral obstructed (UUO) mice are used to explore the potential efficacy of the novel MMP inhibitors in mitigating the fibrotic process.

RESULTS

Treatment with four poricoic acids downregulates profibrotic protein expression in TGF-β1-induced HK-2 cells. Similar results are observed in NRK-52E and NRK-49F cells, indicating that poricoic acids can suppress EMT. Furthermore, both in vitro and in vivo experiments demonstrate that poricoic acid ZI (PZI) exerts a stronger inhibitory effect on protein expression and enzymatic activity of MMP-13 than the other three compounds, which is consistent with the docking results. The inhibitory effect of PZI on MMP-13 is partially attenuated by MMP-13 RNAi in HK-2 cells and UUO mice.

CONCLUSIONS

The findings indicate that as a specific MMP-13 inhibitor, PZI attenuates EMT and renal fibrosis. Therefore, the MMP-13 inhibitor PZI can be a novel therapeutic candidate for limiting EMT and renal fibrosis.

Small molecule inhibitors of epithelial-mesenchymal transition for the treatment of cancer and fibrosis

Tissue fibrosis and cancer both lead to high morbidity and mortality worldwide; thus, effective therapeutic strategies are urgently needed. Because drug resistance has been widely reported in fibrotic tissue and cancer, developing a strategy to discover novel targets for targeted drug intervention is necessary for the effective treatment of fibrosis and cancer. Although many factors lead to fibrosis and cancer, pathophysiological analysis has demonstrated that tissue fibrosis and cancer share a common process of epithelial-mesenchymal transition (EMT). EMT is associated with many mediators, including transcription factors (Snail, zinc-finger E-box-binding protein and signal transducer and activator of transcription 3), signaling pathways (transforming growth factor-β1, RAC-α serine/threonine-protein kinase, Wnt, nuclear factor-kappa B, peroxisome proliferator-activated receptor, Notch, and RAS), RNA-binding proteins (ESRP1 and ESRP2) and microRNAs. Therefore, drugs targeting EMT may be a promising therapy against both fibrosis and tumors. A large number of compounds that are synthesized or derived from natural products and their derivatives suppress the EMT by targeting these mediators in fibrosis and cancer. By targeting EMT, these compounds exhibited anticancer effects in multiple cancer types, and some of them also showed antifibrotic effects. Therefore, drugs targeting EMT not only have both antifibrotic and anticancer effects but also exert effective therapeutic effects on multiorgan fibrosis and cancer, which provides effective therapy against fibrosis and cancer. Taken together, the results highlighted in this review provide new concepts for discovering new antifibrotic and antitumor drugs.

An update of urine and blood metabolomics in chronic kidney disease

Chronic kidney disease is considered as a serious obstacle in global health, with increasing incidence and prevalence. In spite of numerous attempts by using recent omics technologies, specially metabolomics, for understanding pathophysiology, molecular mechanism and identification reliable consensus biomarkers for diagnosis and prognosis of this complex disease, the current biomarkers are still insensitive and many questions about its pathomechanism are still to be unanswered. This review is focused on recent findings about urine and serum/plasma metabolite biomarkers and changes in the pathways that occurs in the disease conditions. The urine and blood metabolome content in the normal and disease state is investigated based on the current metabolomics studies and well known metabolite candidate biomarkers for chronic kidney disease are discussed.

Poricoic acid A enhances melatonin inhibition of AKI-to-CKD transition by regulating Gas6/AxlNFκB/Nrf2 axis

Renal ischemia-reperfusion injury (IRI) is a complex syndrome, which causes chronic kidney disease (CKD) after recovery from IRI-mediated acute kidney injury (AKI). There is no single therapy that could effectively prevent the renal injury after ischemia. In this study, the effects of melatonin or poricoic acid A (PAA) and their combination were investigated in protecting against AKI-to-CKD transition in rats and hypoxia/reoxygenation (H/R)-induced injury in cultured renal NRK-52E cells. Melatonin and PAA significantly reduced the magnitude of rise in serum creatinine and urea levels in IRI rats at days 3 and 14. Our results further showed that treatment with melatonin and PAA ameliorated renal fibrosis and podocyte injury by attenuating oxidative stress and inflammation via regulation of nuclear factor-kappa B (NF-κB) and nuclear factor-erythroid-2-related factor 2 (Nrf2) pathways in IRI rats. Melatonin and PAA protected against AKI-to-CKD transition by regulating growth arrest-specific 6 (Gas6)/AxlNFκB/Nrf2 signaling cascade. Melatonin and PAA initiallyupregulated Gas6/Axl signaling to reduce oxidative stress and inflammation in AKI and subsequently downregulated Gas6/Axl signaling to attenuate renal fibrosis and progression to CKD. Melatonin and PAA inhibited expression of extracellular matrix proteins. Poricoic acid A enhances melatonin-mediated inhibition of AKI-to-CKD transition by the regulating Gas6/AxlNFκB/Nrf2 signaling cascade. Notably, our study first identified Axl as a promising therapeutic target for prevention of AKI-to-CKD transition.

Unilateral ureteral obstruction causes gut microbial dysbiosis and metabolome disorders contributing to tubulointerstitial fibrosis

Chronic kidney disease (CKD) increases the risk and prevalence of cardiovascular disease (CVD) morbidity and mortality. Recent studies have revealed marked changes in the composition of the microbiome and the metabolome and their potential influence in renal disease and CVD via the accumulation of microbial-derived uremic toxins. However, the effect of unilateral ureteral obstruction (UUO) on the gut microbiome and circulating metabolites is unknown. Male Sprague-Dawley rats were randomized to UUO and sham-operated control groups. Renal histology, colonic microbiota, and plasma metabolites were examined two weeks later. We employed 16S rRNA sequence and untargeted metabolomic analyses to explore the changes in colonic microbiota and plasma metabolites and their relationship with tubulointerstitial fibrosis (TIF). The UUO rats exhibited tubular atrophy and dilatation, interstitial fibrosis and inflammatory cell infiltration in the obstructed kidney. UUO rats showed significant colonic enrichment and depletion of genera. Significant differences were identified in 219 plasma metabolites involved in lipid, amino acid, and bile acid metabolism, which were consistent with gut microbiota-related metabolism. Interestingly, tryptophan and its metabolites kynurenine, 5-hydroxytryptophan and 5-hydroxytryptamine levels, which were linked with TIF, correlated with nine specific genera. Plasma tryptophan level was positively correlated with Clostridium IV, Turicibacter, Pseudomonas and Lactobacillales, and negatively correlated with Oscillibacter, Blautia, and Intestinimonas, which possess the genes encoding tryptophan synthase (K16187), indoleamine 2,3-dioxygenase (K00463) and tryptophan 2,3-dioxygenase (K00453) and their corresponding enzymes (EC:1.13.11.52 and EC:1.13.11.11) that exacerbate TIF. In conclusion, UUO results in profound changes in the gut microbiome and circulating metabolites, events that contribute to the pathogenesis of inflammation and TIF.

AKF-PD alleviates diabetic nephropathy via blocking the RAGE/AGEs/NOX and PKC/NOX Pathways

Diabetic nephropathy (DN) is a major complication of diabetes. Currently, drugs are not available to effectively control the disease. Fluorofenidone (AKF-PD) is a recently developed drug; it possesses activities in reducing DN progression in preclinical research. Nonetheless, its renal protection and the underlying mechanisms have not been thoroughly investigated. We report here that AKF-PD significantly alleviatesrenal oxidative stress (OS) in db/dbmice through downregulation of Nicotinamide Adenine Dinucleotide Phosphate (NADPH) oxidase and upregulation of glutathione peroxidase and superoxide dismutase, thereby protecting kidney from DN pathogenesis. AKF-PD likely reduces OS through the advanced glycation end products (AGE) and protein kinase C (PKC) pathways. While renal AGEs, PKCα, PKCβ, and NADPH oxidase 4 (NOX4) were all substantially upregulated in db/db mice compared to db/m animals, AKF-PD robustly downregulated all these events to the basal levelsdetected in db/m mice. In primary human renal mesangial cells (HMCs), high glucose (HG) elevated receptor for advanced glycation endproducts (RAGE), PKCα, PKCβ and NOX4 activity, and induced the production of reactive oxygen species (ROS); these events were all inhibited by AKF-PD. Furthermore, HG led to mitochondrial damagein HMCs;AKF-PD conferred protection on the damage. Knockdown of either PKCα or PKCβ reduced HG-induced ROS production and mitochondrial damage in HMCs. The knockdown significantly enhanced AKF-PD-mediated inhibition of ROS production and mitochondrial damage in HG-treated HMCs. Collectively, our study demonstrates that AKF-PD protects renal function under diabetes conditions in part through inhibition of OS during DN pathogenesis. AKF-PD can be explored for clinical applications in DN therapy.

Metabolomics Approaches for the Diagnosis and Understanding of Kidney Diseases

Diseases of the kidney are difficult to diagnose and treat. This review summarises the definition, cause, epidemiology and treatment of some of these diseases including chronic kidney disease, diabetic nephropathy, acute kidney injury, kidney cancer, kidney transplantation and polycystic kidney diseases. Numerous studies have adopted a metabolomics approach to uncover new small molecule biomarkers of kidney diseases to improve specificity and sensitivity of diagnosis and to uncover biochemical mechanisms that may elucidate the cause and progression of these diseases. This work includes a description of mass spectrometry-based metabolomics approaches, including some of the currently available tools, and emphasises findings from metabolomics studies of kidney diseases. We have included a varied selection of studies (disease, model, sample number, analytical platform) and focused on metabolites which were commonly reported as discriminating features between kidney disease and a control. These metabolites are likely to be robust indicators of kidney disease processes, and therefore potential biomarkers, warranting further investigation.

Microbiome-metabolome reveals the contribution of gut-kidney axis on kidney disease

Dysbiosis represents changes in composition and structure of the gut microbiome community (microbiome), which may dictate the physiological phenotype (health or disease). Recent technological advances and efforts in metagenomic and metabolomic analyses have led to a dramatical growth in our understanding of microbiome, but still, the mechanisms underlying gut microbiome–host interactions in healthy or diseased state remain elusive and their elucidation is in infancy. Disruption of the normal gut microbiota may lead to intestinal dysbiosis, intestinal barrier dysfunction, and bacterial translocation. Excessive uremic toxins are produced as a result of gut microbiota alteration, including indoxyl sulphate, p-cresyl sulphate, and trimethylamine-N-oxide, all implicated in the variant processes of kidney diseases development. This review focuses on the pathogenic association between gut microbiota and kidney diseases (the gut–kidney axis), covering CKD, IgA nephropathy, nephrolithiasis, hypertension, acute kidney injury, hemodialysis and peritoneal dialysis in clinic. Targeted interventions including probiotic, prebiotic and symbiotic measures are discussed for their potential of re-establishing symbiosis, and more effective strategies for the treatment of kidney diseases patients are suggested. The novel insights into the dysbiosis of the gut microbiota in kidney diseases are helpful to develop novel therapeutic strategies for preventing or attenuating kidney diseases and complications.

Jian-Pi-Yi-Shen Formula ameliorates chronic kidney disease: involvement of mitochondrial quality control network

BACKGROUND

Jian-Pi-Yi-Shen Formula (JPYSF), a Chinese herbal decoction with the efficacies of 'fortify the spleen and tonify the kidney' and 'activate blood and resolve stasis', is effective for the treatment of chronic kidney disease in clinic. However, the underlying mechanism remains unclear. The aim of this study was to investigate the therapeutic effects and possible mechanisms of JPYSF on retarding chronic kidney disease progression in 5/6 nephrectomized (5/6 Nx) rats.

METHODS

Perindopril (4 mg/kg/d) and JPYSF (2.72 g/kg/d) were administrated by gavage to 5/6 Nx rats daily for 6 weeks. The therapeutic effects of JPYSF were evaluated by renal function, pathological injury, and fibrosis. The protein levels associated with mitochondrial quality control network were measured by Western blot and immunofluorescence analysis.

RESULTS

5/6 Nx rats showed obvious decline in renal function as evidenced by increased serum creatinine, blood urea nitrogen, and urinary protein excretion, and significant injury in kidney structure as evidenced by glomerular hypertrophy, tubular atrophy, and interstitial fibrosis. Administration of JPYSF for 6 weeks could improve renal function and ameliorate kidney structure injury in 5/6 Nx rats. Furthermore, the remnant kidneys of 5/6 Nx rats showed unbalanced mitochondrial quality control network manifested as decreased mitochondrial biogenesis, fusion, and mitophagy, and increased mitochondrial fission. Treatment of JPYSF could restore aforesaid aspects of mitochondrial quality control network.

CONCLUSIONS

These results indicate that JPYSF can notably ameliorate 5/6 Nx-induced chronic kidney disease, which may be related with modulation of mitochondrial quality control network.

Natural products for the prevention and treatment of kidney disease

BACKGROUND

Chronic kidney disease (CKD) is one of the common causes resulting in a high morbidity and mortality. Renal fibrosis is the main pathological features of CKD. Natural products have begun to gain widely popularity worldwide for promoting healthcare and preventing CKD, and have been used as a conventional or complementary therapy for CKD treatment.

PURPOSE

The present paper reviewed the therapeutic effects of natural products on CKD and revealed the molecular mechanisms of their anti-fibrosis.

METHODS

All the available information on natural products against renal fibrosis was collected via a library and electronic search (using Web of Science, Pubmed, ScienceDirect, Splinker, etc.).

RESULTS

Accumulated evidence demonstrated that natural products exhibited the beneficial effects for CKD treatment and against renal fibrosis. This review presents an overview of the molecular mechanism of CKD and natural products against renal fibrosis, followed by an in-depth discussion of their molecular mechanism of natural products including isolated compounds and crude extracts against renal fibrosis in vitro and in vivo. A number of isolated compounds have been confirmed to retard renal fibrosis.

CONCLUSION

The review provides comprehensive insights into pathophysiological mechanisms of CKD and natural products against renal fibrosis. Particular challenges are presented and placed within the context of future applications of natural products against renal fibrosis.

Carboxymethyl pachyman (CMP) reduces intestinal mucositis and regulates the intestinal microflora in 5-fluorouracil-treated CT26 tumour-bearing mice

The compound 5-fluorouracil (5-FU) is the first choice chemotherapeutic agent for the treatment of colorectal cancer (CRC), but intestinal mucositis is a primary limiting factor in anticancer therapy. There is currently no broadly effective targeted treatment to cure this side effect. Carboxymethylated pachyman (CMP) is a polysaccharide that is modified from the structure of pachyman isolated from Poria cocos (Chinese name: Fu Ling). Meanwhile, recent studies have shown that CMP exhibits immune regulatory, anti-inflammatory and antioxidant activities. Therefore, the purpose of this study was to evaluate the intestinal protective effect of CMP in 5-FU-treated CT26 tumour-bearing mice and to further explore its underlying mechanism(s) of action. Initially, a CT26 colon carcinoma xenograft mice model was established. The colon length, colon tissue injury, intestinal flora, short-chain fatty acids (SCFAs) and indicators linked to inflammation, antioxidation and apoptosis were then measured. Our results showed that CMP in combination with 5-FU reversed intestinal shortening (p < 0.01) and alleviated 5-FU-induced colon injury (p < 0.001) via suppression of ROS production; increasing the levels of CAT, GSH-Px and GSH; decreasing expression of NF-κB, p-p38 and Bax; and elevating the levels of Nrf2 and Bcl-2. More importantly, CMP had a significant impact and counteracted the intestinal microflora disorders produced by 5-FU by increasing the proportion of Bacteroidetes, lactobacilli, and butyric acid-producing and acetic acid-producing bacteria and restoring the intestinal flora diversity. Overall, this work suggested that CMP could regulate the ecological balance of the intestinal flora and reduce colon injuries induced by 5-FU in CT26 tumour-bearing mice, and the mechanism involved may be associated with the regulation of the NF-κB, Nrf2-ARE and MAPK/P38 pathways.

Renoprotective effect of Zhenwu decoction against renal fibrosis by regulation of oxidative damage and energy metabolism disorder

Zhenwu decoction (ZWD) is a promising traditional Chinese prescription against renal fibrosis, while its underlying mechanism remains unclear. Rat model of renal fibrosis were established and divided into control group, model group, ZWD treatment group and enalapril maleate treatment group. Metabolic profiles on serum samples from each group were acquired by using ultra performance liquid chromatography coupled with quadrupole time-of-flight high-resolution mass spectrometry. Metabolomics combined with molecular biology were comparatively conducted on samples of various groups. Fifteen potential biomarkers were identified and these biomarkers are mainly phospholipids and fatty acids. The results showed renal fibrosis was associated with oxidative damage and energy metabolism disorder. The results of histopathology, biochemistry and metabolomics demonstrated that ZWD exhibited an efficient renoprotective effect by alleviating oxidative stress, increasing energy metabolism and regulating fibrotic cytokines. This study provided scientific support for the research and development of new drugs from traditional Chinese medicine.

Rhubarb Protect Against Tubulointerstitial Fibrosis by Inhibiting TGF-β/Smad Pathway and Improving Abnormal Metabolome in Chronic Kidney Disease

Tubulointerstitial fibrosis is the final common pathway for all kidney diseases leading to chronic kidney disease (CKD). TGF-β/Smad signaling pathway plays a key role in renal fibrosis. Previous studies have revealed that rhubarb extracts attenuated the increase of transforming growth factor-β 1 (TGF-β1) in CKD rats. To gain an in-depth insight into the mechanism of the anti-fibrotic activities of the rhubarb extracts, we investigated the influence of rhubarb extracts on TGF-β/Smad signaling pathway and the influence on metabolome in a rat model of CKD with adenine-induced chronic tubulointerstitial nephropathy. Male Sprague-Dawley rats were divided into four groups, including control, CKD, CKD + petroleum ether extract, CKD + ethyl acetate extract, and CKD + n-butanol extract groups. Kidneys harvested on the week three were evaluated for renal fibrosis, the expression of proteins in TGF-β/Smad signaling pathway and metabolomic study. We found rhubarb extracts suppressed TGF-β/Smad3-mediated renal fibrosis by reducing the TGF-β1, transforming growth factor-β receptor I (TGF-β RI), transforming growth factor-β receptor II (TGF-β RII), Smad2, p-Smad2, Smad3, p-Smad3, and Smad4, meanwhile increased Smad7. In addition, rhubarb extracts mitigated renal injury and dysfunction, and either fully or partially reversed the abnormalities of tissue metabolites. Thus, rebalancing the disorder of TGF-β/Smad signaling and metabolic dysfunction by treatment with rhubarb extracts may represent as an effective therapy for CKD associated with fibrosis.

Novel inhibitors of the cellular renin-angiotensin system components, poricoic acids, target Smad3 phosphorylation and Wnt/β-catenin pathway against renal fibrosis

BACKGROUND AND PURPOSE

Tubulo-interstitial fibrosis is the final pathway in the progression of chronic kidney disease (CKD) to kidney failure. The renin-angiotensin system (RAS) plays a major role in CKD progression. Hence, we determined the efficacy of novel RAS inhibitors isolated from Poria cocos against renal fibrosis.

EXPERIMENTAL APPROACH

Effects of three novel tetracyclic triterpenoid compounds, poricoic acid ZC (PZC), poricoic acid ZD (PZD) and poricoic acid ZE (PZE), were investigated on TGFβ1- and angiotensin II (AngII)-treated HK-2 cells and unilateral ureteral obstruction (UUO) in mice. Immunofluorescence staining, quantitative real-time PCR, siRNA, co-immunoprecipitation and Western blot analyses were used to evaluate expression of key molecules in RAS, Wnt/β-catenin and TGFβ/Smad pathways.

KEY RESULTS

Addition of the above compounds to culture media and their administration to UUO mice: (i) significantly attenuated epithelial-to-mesenchymal transition and extracellular matrix production in TGFβ1- and AngII-treated HK-2 cells and UUO mice by inhibiting Wnt/β-catenin pathway activation and Smad3 phosphorylation; (ii) selectively inhibited Smad3 phosphorylation by blocking the interaction of TGFBR1 with Smad3; and (iii) specifically inhibited Smad3 activation. PZC and PZD showed a strong inhibitory effect on all RAS components, and PZE showed a strong inhibitory effect on renin. Furthermore, the secolanostane tetracyclic triterpenoids, PZC and PZD, showed a stronger inhibitory effect than the lanostane tetracyclic triterpenoid PZE. Therefore, compounds with secolanostance skeleton showed stronger bioactivity than those with lanostance skeleton.

CONCLUSION AND IMPLICATIONS

The secolanostane tetracyclic triterpenoids effectively blocked RAS by simultaneously targeting multiple RAS components and lanostane tetracyclic triterpenoids inhibited renin and protected against tubulo-interstitial fibrosis.

The intervention effect of zuogui pill on chronic kidney disease-mineral and bone disorder regulatory factor

Chronic kidney disease-mineral and bone disorder (CKD-MBD) play a critical role in the pathogenesis of cardiovascular complications in patients with chronic kidney disease (CKD). Zuogui pill as a traditional Chinese herbal drug has been used for nourish kidney essence improve bone malnutrition of renal bone disease by regulating the metabolism of calcium and phosphorus and participating in osteoblast metabolism. In the present study, 5/6 nephrectomy rat model was used to reveal the mechanism of zuogui pill in treatment of CKD-MBD. Compared with sham rats, the levels of serum phosphorus, PTH, iPTH and creatinine were significantly decreased, while the serum calcium level was significantly increased, and the Cbfa1 protein level was significantly decreased and FGF23 protein level was significantly increased by Zuogui pill treatment. Compared with model rats, the BMD of rat was significantly increased by Zuogui pill treatment. Histological analysis revealed that the kidney injury of rats with CKD was significantly reduced by zuogui pill treatment. Compared with model rats, the CYP27B1 mRNA level was significantly increased, and the PTH mRNA level and NaPiIIa protein level were significantly decreased in the kidney by zuogui pill treatment. We inferred that zuogui pill exhibited potential therapeutic effects on CKD-MBD in the rats by regulating bone metabolism and nourish kidney.

Molecular mechanism of Poria cocos combined with oxaliplatin on the inhibition of epithelial-mesenchymal transition in gastric cancer cells

PURPOSE

Natural product Poria cocos possesses antitumor effect. This study will explore the molecular mechanism of Poria cocos combined with chemotherapy in the inhibition of gastric cancer cell EMT process.

METHODS

The experiment was divided into blank control group, Poria cocos group, oxaliplatin group and Poria cocos combined with oxaliplatin group. Scratch and Transwell assay were used to detect cell migration and invasion respectively. RT-qPCR and Western Blot analyses were used to detect mRNA and protein expression of the epithelial-mesenchymal transition (EMT) related factors including Snail, Twist, Vimentin, E-cadherin and N-cadherin respectively. Morphologic assessment was performed with HPIAS-1000 automated image analysis system.

RESULTS

The migration and invasion abilities of gastric cancer cells in the Poria cocos combined with oxaliplatin group were significantly decreased (P < 0.01). The mRNA and protein expression of Snail, Twist, Vimentin and N-cadherin were significantly decreased while the mRNA and protein expression of E-cadherin were significantly increased (P < 0.01) compared with blank control group. Nude mice model of gastric cancer was successfully established. Poria cocos combined with oxaliplatin could significantly inhibit gastric tumor progression. The expression of EMT related factors were consistent with in vitro study. Morphologic assessment showed that the nucleus area, perimeter, mean diameter, volume, long diameter and shape factor in the Poria cocos combined with oxaliplatin group were significantly different compared with the blank control group (P < 0.01) but not significantly different compared with the normal control.

CONCLUSIONS

Poria cocos combined with oxaliplatin could significantly inhibit the migration and invasion of gastric cancer cells. Through both in vitro and in vivo studies, it is confirmed that Poria cocos combined with oxaliplatin could significantly inhibit the EMT process of gastric cancer. Poria cocos combined with oxaliplatin could significantly affect the morphology changes of gastric cancer cells. These findings may provide a theoretical guidance for the clinical treatment of gastric cancer.

Metabolic profiles revealed anti-ischemia-reperfusion injury of Yangxinshi tablet in Rats

ETHNOPHARMACOLOGICAL RELEVANCE

Myocardial ischemia-reperfusion (I/R) injury is a serious injury that is resulted from the recovery of blood supply after myocardial ischemia. Yangxinshi tablet is a compound Chinese herbal preparation and often used to alleviate the myocardial ischemia in clinical, but its protective mechanism of anti-myocardial ischemia reperfusion injury remains unclear. The objective of this study was to evaluate the anti-I/R injury effect of Yangxinshi tablet on a myocardial I/R rat model and to identify serum biomarker metabolites associated with I/R based on ultra-high performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF/MS) metabolomic method, and explore the metabolic mechanism of anti-I/R injury of Yangxinshi tablet.

MATERIALS AND METHODS

Unsupervised principle component analysis highlighted significant differences in the metabolome of the myocardial I/R, healthy control and drug-treated rats. Partial least squares-discriminant analysis revealed 25 metabolites as the most potential biomarker metabolites discriminating the myocardial I/R rats and control rats. Most of the metabolites were primarily involved in oxidative stress, energy metabolism, fatty acid metabolism, amino acid metabolism. These metabolites were validated by assessing the efficacy after intragastric administration of Yangxinshit ablet to the myocardial I/R rat model.

RESULTS

Based on metabolomic results, the action mechanism of anti-I/R injury of Yangxinshi tablet was concluded as follows: (1) enhance the ability of scavenging free radicals and reactive oxygen species in vivo; (2) provide energy for myocardium via accelerating the intracellular carnitine transportion to accelerate the oxidation of fatty acid and (3) attenuate ceramide to reduce cardiomyocyte apoptosis.

CONCLUSIONS

Yangxinshi tablet has cardio-protection effects on I/R rats via regulation of multiple metabolic pathways involving in oxidative stress, energy metabolism, fatty acid, and amino acid metabolisms. This study will be meaningful for its clinical application and valuable for further exploring the action mechanism of Yangxinshi tablet.

Zhen-wu-tang protects against podocyte injury in rats with IgA nephropathy via PPARγ/NF-κB pathway

Zhen-wu-tang (ZWT) has been widely applied in chronic kidney diseases. However, the mechanism of ZWT remains unclear. Peroxisome proliferator-activated receptors-γ (PPARγ) is known as a protective factor for podocyte and kidney function. This study is aimed to investigate the protective effects of ZWT on IgA nephropathy (IgAN) in rats against podocyte injury and the underlying mechanism related to PPARγ. IgAN model rats were induced by administering bovine serum albumin, lipopolysaccharide, and carbon tetrachloride. ZWT at two doses and GW9662 (PPARγ antagonist) was administered once daily for 4 weeks respectively. Cultured podocyte induced by LPS were used to evaluate the podocyte-protective effect and related mechanism of ZWT in vitro. Results showed that ZWT observably reduced proteinuria and hematuria excretion, as well as the levels of blood urea nitrogen, serum creatinine, serum uric acid, low-density lipoprotein cholesterol, total cholesterol and triglycerides, but increased the contents of high-density lipoprotein cholesterol, ameliorating renal function and hyperlipidemia state in IgAN rats. Besides, both ZWT administration groups alleviated kidney pathological lesion, macrophage infiltration, IgA and C3 deposition in glomeruli. To further demonstrate the protective effects of ZWT, we found that podocyte damage was markedly ameliorated with ZWT treatments in IgAN rats and LPS-induced podocyte injury model by suppressing the expressions of desmin, reducing podocyte apoptosis and augmenting nephrin and podocin levels. Moreover, ZWT inhibited the phosphorylation of NF-κB and IκBα, simultaneously upregulated PPARγ. However, GW9662 made no difference in all the above effects compared to the model group, and was reversed by ZWT in vitro study. In conclusion, these results demonstrated that ZWT ameliorated IgAN-induced podocyte injury via upregulation PPARγ and the underlying mechanism might involve the inhibition of NF-κB pathway.

Novel RAS Inhibitors Poricoic Acid ZG and Poricoic Acid ZH Attenuate Renal Fibrosis via a Wnt/β-Catenin Pathway and Targeted Phosphorylation of smad3 Signaling

Renal fibrosis is a common end point of the progression of chronic kidney disease (CKD). Suppressing the development and progression of renal fibrosis is essential in the treatment of kidney disease. Our previous study demonstrated that the ethyl acetate extract of the surface layer of Poria cocos exhibited beneficial antitubulointerstitial fibrosis. In this study, we isolated new diterpene (PZF) and triterpenes (PZG and PZH) and examined their antifibrotic effect. TGF-β1 upregulated the collagen I protein expression in HK-2 cells, and PZG and PZH treatment significantly inhibited the upregulated collagen I expression (TGF group 0.59 ± 0.08 vs TGF+PZG group 0.36 ± 0.08, P < 0.01; TGF+PZH group 0.39 ± 0.12, P < 0.01). Triterpenes, PZG and PZH, exhibited a stronger inhibitory effect on renal fibrosis and podocyte injury than PZF. PZG and PZH further showed a stronger inhibitory effect on the activation of the renin-angiotensin system (RAS) than PZF. Additionally, PZG and PZH markedly inhibited the activation of Wnt/β-catenin signaling, which played an important role in fibrogenesis. Interestingly, PZG and PZH suppressed the TGF-β/Smad pathway by selectively inhibiting the phosphorylation of Smad3 through blocking the interactions of SARA with TGFβI and Smad3. The analysis of the structure-activity relationship demonstrated that their antifibrotic effects were closely associated with the first six-membered ring structure and the number of carboxyl groups in this type of compounds. Additionally, fifteen known triterpenes were identified. These novel tetracyclic triterpenoid compounds provided the potential lead compounds for the research and development of antifibrosis drug, and they possessed the potential to be utilized as RAS inhibitors.

Intestinal tract is an important organ for lowering serum uric acid in rats

The kidney was recognized as a dominant organ for uric acid excretion. The main aim of the study demonstrated intestinal tract was an even more important organ for serum uric acid (SUA) lowering. Sprague-Dawley rats were treated normally or with antibiotics, uric acid, adenine, or inosine of the same molar dose orally or intraperitoneally for 5 days. Rat’s intestinal tract was equally divided into 20 segments except the cecum. Uric acid in serum and intestinal segment juice was assayed. Total RNA in the initial intestinal tract and at the end ileum was extracted and sequenced. Protein expression of xanthine dehydrogenase (XDH) and urate oxidase (UOX) was tested by Western blot analysis. The effect of oral UOX in lowering SUA was investigated in model rats treated with adenine and an inhibitor of uric oxidase for 5 days. SUA in the normal rats was 20.93±6.98 μg/ml, and total uric acid in the intestinal juice was 308.27±16.37 μg, which is two times more than the total SUA. The uric acid was very low in stomach juice, and attained maximum in the juice of the first segment (duodenum) and then declined all the way till the intestinal end. The level of uric acid in the initial intestinal tissue was very high, where XDH and most of the proteins associated with bicarbonate secretion were up-regulated. In addition, SUA was decreased by oral UOX in model rats. The results suggested that intestinal juice was an important pool for uric acid, and intestinal tract was an important organ for SUA lowering. The uric acid distribution was associated with uric acid synthesis and secretion in the upper intestinal tract, and reclamation in the lower.

Poricoic acid ZA, a novel RAS inhibitor, attenuates tubulo-interstitial fibrosis and podocyte injury by inhibiting TGF-β/Smad signaling pathway

BACKGROUND

The pathogenesis of tubulo-interstitial fibrosis and glomerulosclerosisis was characterized by cellular hypertrophy, extracellular matrix accumulation and podocyte detachment. Poricoic acid ZA (PZA) is a tetracyclic triterpenoid compound extracted from the surface layer of Poria cocos (LPC), which have been used extensively for diuretic and renoprotective effects.

METHODS

The anti-fibrotic effect of PZA is investigated in HK-2 cells and podocytes induced by TGF-β1 and angiotensin II (ANGII). qRT-PCR, siRNA, immunofluorescence staining, co-immunoprecipitation and Western blot analyses are used to evaluate the expression of RAS signaling, TGF-β/Smad pathway, epithelial-to-mesenchymal transition (EMT) and podocyte markers.

RESULTS

PZA restores the mRNA and protein expression of EMT in HK-2 cells. Specific TGF-β1-siRNA efficiently blocks ANGII-induced protein expression of TGF-β1 and further inhibits activated Smad signaling. PZA significantly attenuates up-regulation of angiotensinogen, renin, ACE and AT1. Further, PZA reverses up-regulation of TGFβRII and suppresses Smad proteins. Simultaneously, PZA inhibits the protein interaction of TGF-β receptor and Smads and PZA also inhibits activated RAS and TGF-β/Smad signaling cascade and up-regulates protein expression of podocyte markers and mitigates podocyte injury.

CONCLUSIONS

This study demonstrated the beneficial role of PZA in renal fibrosis and podocyte injury. Our study highlighted that PZA inhibits RAS and further suppresses TGF-β/Smad pathway through inhibiting Smad2/3 phosphorylation via blocking Smad2/3-TGFβRI protein interaction. PZA is implicated in activation of RAS/TGF-β/Smad axis in HK-2 cells and podocytes. PZA could be considered as a novel RAS inhibitor for treating CKD.

1H-NMR Based Serum Metabolomics Study to Investigate Hepatoprotective Effect of Qin-Jiao on Carbon Tetrachloride-Induced Acute Hepatotoxicity in Rats

Gentiana macrophylla Radix, commonly known as Qin-Jiao (QJ), was recorded alone to treat jaundice in Compendium of Materia Medica and has been frequently prescribed for treatment of liver disease in China. However, the underlying mechanism remains unknown. In the present work, QJ of 1,2 g/kg or silybin of 40 mg/kg (positive control) was orally given to rats for 7 days to verify the protective effect on acute liver damage induced by tetrachloride (CCl₄). Together with serum biochemistry and histopathological examination, ¹H-NMR based metabolomics work was carried out to investigate the efficacy. It turned out that QJ of 2 g/kg exerted comparable protective effect with positive control and partially recovered disturbed metabolism by CCl₄. Multivariate analysis was conducted and metabolites altered significantly among groups were assigned and discussed, including betaine, glucose, lactate, creatine, and LDL/VLDL. Metabolic regulations involved in QJ or silybin treatment were as follows: tricarboxylic acid (TCA) cycle, synthesis of LDL/VLDL, and gluconeogenesis were enhanced, while betaine metabolism, glycolysis, creatine metabolism, synthesis of ketone bodies, amino acids metabolism, and β-oxidation of fatty acids were suppressed. For the first time hepatoprotective effect of QJ on acute liver damage was revealed by ¹H-NMR based metabolomics, prompting understanding of the underlying mechanism.

Protective Effects of Ophiocordyceps lanpingensis on Glycerol-Induced Acute Renal Failure in Mice

Objective

Oxidative stress and immune response are associated with acute renal failure (ARF). Ophiocordyceps lanpingensis (OL) might be an antioxidant and immunopotentiator. In this study, we explored the protective effects of OL on glycerol-induced ARF.

Methods

Male mice were randomly divided into four groups, specifically, glycerol-induced ARF model group, low-dose OL-treated group (1.0 g/kg/d), high-dose OL-treated group (2.0 g/kg/d), and control group. Renal conditions were evaluated using kidney index, serum creatinine (Cr), blood urea nitrogen (BUN), and histological analysis. Rhabdomyolysis was monitored using creatine kinase (CK) level. Oxidative stress was determined using kidney tissue glutathione (GSH), malondialdehyde (MDA), and superoxide dismutase (SOD) levels. Immune status was evaluated using immune organ indices and immunoglobulin G (IgG) level.

Results

OL could relieve renal pathological injury and decrease the abnormal levels of kidney index, serum Cr, CK, BUN, and MDA, as well as increase the immune organ indices and the levels of IgG, GSH, and SOD. Treatment with a high dose of OL had more positive therapeutic effects on ARF than using a low dose of OL.

Conclusion

OL could ameliorate renal dysfunction in glycerol-induced ARF in mice by inhibiting oxidative stress and enhancing immune response.

Antitumorpharmacological mechanism of the oral liquid of Poriacocos polysaccharide

ETHNOPHARMACOLOGICAL RELEVANCE

The liquid oral formulation of Poria cocos polysaccharides is composed of polysaccharides of Lentinusedodes, Ganodermalucidum and Poria cocos(1:1:2), which are all fungi used in traditional Chinese medicine. Polysaccharides extracted from these fungi have been reported to exhibit an antitumor effect by modulating the immune system.

AIM OF THE STUDY

The present study aimed to clarify the antitumor mechanism of an orally administered liquid containing Poriacocos and to further provide clinical guidance.

MATERIALS AND METHODS

In this study, the effects of an orally administered liquid containing Poriacocos polysaccharides on the solid tumors formed from sarcoma 180 cells in mice were evaluated. The protein expression of Bcl-2, caspase-3, and caspase-9in the thymus, spleen and liver tissues in the mice was determined by Western blot analysis. In addition, hematoxylin-eosin（H&E）staining and immunohistochemistry were performed on thymus, spleen and liver tissue and the positive staining rate was calculated for the three protein expression.

RESULTS

The liquid oral formulation of Poriacocos polysaccharides reduced Bcl-2 protein levels and increased caspase-3 and -9 protein levels in sarcoma 180 cells.

CONCLUSION

The mechanism underlying the antitumor effects of the oral liquid formulation of Poriacocos polysaccharides involved inhibition of Bcl-2 expression and activation of caspase-9 expression in sarcoma 180 cells. Furthermore, the downstream caspase-3 promoter cascade was activated and cell apoptosis was activated in sarcoma 180 cells.

Erhuang Formula ameliorates renal damage in adenine-induced chronic renal failure rats via inhibiting inflammatory and fibrotic responses

AIMS

The present study aimed to evaluate the protective effects of Erhuang Formula (EHF) and explore its pharmacological mechanisms on adenine-induced chronic renal failure (CRF).

MATERIALS AND METHODS

The compounds in EHF were analyzed by HPLC/MS. Adenine-induced CRF rats were administrated by EHF. The effects were evaluated by renal function examination and histology staining. Immunostaining of some proteins related cell adhesion was performedin renal tissues, including E-cadherin, β-catenin, fibronectin and laminin. The qRT-PCR was carried out determination of gene expression related inflammation and fibrosis including NF-κB, TNF-α, TGF-β1, α-SMA and osteopontin (OPN).

RESULTS

Ten compounds in EHF were identified including liquiritigenin, farnesene, vaccarin, pachymic acid, cycloastragenol, astilbin, 3,5,6,7,8,3',4'-heptemthoxyflavone, physcion, emodin and curzerene. Abnormal renal function and histology had significant improvements by EHF treatment. The protein expression of β-catenin, fibronectin and laminin were significantly increased and the protein expression of E-cadherin significantly decreased in CRF groups. However, these protein expressions were restored to normal levels in EHF group. Furthermore, low expression of PPARγ and high expression of NF-κB, TNF-α, TGF-β1, α-SMA and OPN were substantially restored by EHF treatment in a dose-dependent manner.

CONCLUSIONS

EHF ameliorated renal damage in adenine-induced CRF rats, and the mechanisms might involve in the inhibition of inflammatory and fibrotic responses and the regulation of PPARγ, NF-κB and TGF-β signaling pathways.

A Chinese herbal formula, Jian-Pi-Yi-Shen decoction, improves muscle atrophy via regulating mitochondrial quality control process in 5/6 nephrectomised rats

Muscle atrophy is one of the serious complications of chronic kidney disease (CKD). Dysregulation of mitochondrial quality control (MQC) process, including decrease mitochondrial biogenesis, impair mitochondrial dynamics and induce activation of mitophagy, play an important role in mediating muscle wasting. This study aimed to observe effects of Jian-Pi-Yi-Shen (JPYS) decoction on muscle atrophy in CKD rats and explore its possible mechanism on regulation of MQC processes. The 5/6 nephrectomised rats were randomly allocated into 2 groups: CKD group and JPYS group. Besides, a sham-operated rats as sham group. All rats were treated for 6 weeks. Results showed that administration of JPYS decoction prevented body weight loss, muscle loss, muscle fiber size decrease, muscle protein degradation, and increased muscle protein systhesis. In addition, JPYS decoction increased the mitochondrial content and biogenesis proteins, and down-regulated the autophagy and mitophagy proteins. Furthermore, JPYS decoction increased mitochondrial fusion proteins, while decreased mitochondrial fission proteins. In conclusion, JPYS decoction increased mitochondrial content and biogenesis, restore the balance between fission and fusion, and inhibited autophagy-lysosome pathway (mitophagy). Collectively, our data showed that JPYS decoction to be beneficial to muscle atrophy in CKD, which might be associated with the modulation of MQC process.

Disease-syndrome combination modeling: metabolomic strategy for the pathogenesis of chronic kidney disease

Conventional disease animal models have limitations on the conformity to the actual clinical situation. Disease-syndrome combination (DS) modeling may provide a more efficient strategy for biomedicine research. Disease model and DS model of renal fibrosis in chronic kidney disease were established by ligating the left ureter and by ligating unilateral ureteral combined with exhaustive swimming, respectively. Serum metabolomics was conducted to evaluate disease model and DS model by using ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Potential endogenous biomarkers were identified by multivariate statistical analysis. There are no differences between two models regarding their clinical biochemistry and kidney histopathology, while metabolomics highlights their difference. It is found that abnormal sphingolipid metabolism is a common characteristic of both models, while arachidonic acid metabolism, linolenic acid metabolism and glycerophospholipid metabolism are highlighted in DS model. Metabolomics is a promising approach to evaluate experiment animal models. DS model are comparatively in more coincidence with clinical settings, and is superior to single disease model for the biomedicine research.