Resveratrol ameliorates renal injury in spontaneously hypertensive rats by inhibiting renal micro-inflammation

Drug pair of Cornus officinalis and Radix achyranthis bidentatae improves renal injury of hypertension by regulating metabolic reprogramming mediated by eNOS

Objective

To explore the effects and possible mechanisms of the drug pair Cornus officinalis and Radix achyranthis bidentatae (SYR-NX) on improving hypertensive kidney damage.

Method

SYR-NX, a formulation of Cornus officinalis and Radix Achyranthis Bidentatae with a dose ratio 1:2.5, was used in this experiment. We investigated the effects of SYR-NX on spontaneously hypertensive rats (SHR) fed with a high-salt diet and Human Kidney-2 (HK2) cells exposed to hypoxia. After 8 weeks of treatment with SYR-NX, blood pressure was tested, and β 2-Microglobulin(β2-MG), blood creatinine (S-cr), endothelial nitric oxide synthase (eNOS), nicotinamide adenine dinucleotide phosphate (NADPH), M2 pyruvate kinase (PKM2), adenosine triphosphate (ATP), pyruvate, lactate, connective tissue growth factor (CTGF) and tumor necrosis factor-α (TNF-α)were measured. HK2 cells pre-treated with SYR-NX were cultured in a three-gas hypoxic incubator chamber (5 % CO2, 1 % O2, 94 % N2) for 12 h, and then eNOS, PKM2, NADPH, ATP, pyruvate, lactate, CTGF and TNF-α were assessed.

Results

SYR-NX significantly reduced SBP, DBP, β2-MG, S-cr, PKM2, pyruvate, lactate, CTGF and TNF-α, and increased eNOS, NADPH, and ATP.

Conclusion

SYR-NX can regulate metabolic reprogramming through eNOS and improves hypertensive kidney injury.

ELABELA-derived peptide ELA13 attenuates kidney fibrosis by inhibiting the Smad and ERK signaling pathways

Kidney fibrosis is an inevitable result of various chronic kidney diseases (CKDs) and significantly contributes to end-stage renal failure. Currently, there is no specific treatment available for renal fibrosis. ELA13 (amino acid sequence: RRCMPLHSRVPFP) is a conserved region of ELABELA in all vertebrates; however, its biological activity has been very little studied. In the present study, we evaluated the therapeutic effect of ELA13 on transforming growth factor-β1 (TGF-β1)-treated NRK-52E cells and unilateral ureteral occlusion (UUO) mice. Our results demonstrated that ELA13 could improve renal function by reducing creatinine and urea nitrogen content in serum, and reduce the expression of fibrosis biomarkers confirmed by Masson staining, immunohistochemistry, real-time polymerase chain reaction (RT-PCR), and western blot. Inflammation biomarkers were increased after UUO and decreased by administration of ELA13. Furthermore, we found that the levels of essential molecules in the mothers against decapentaplegic (Smad) and extracellular signal-regulated kinase (ERK) pathways were reduced by ELA13 treatment in vivo and in vitro. In conclusion, ELA13 protected against kidney fibrosis through inhibiting the Smad and ERK signaling pathways and could thus be a promising candidate for anti-renal fibrosis treatment.

Patchouli alcohol against renal fibrosis of spontaneously hypertensive rats via Ras/Raf-1/ERK1/2 signalling pathway

OBJECTIVES

The present study was designed to obverse the protection of patchouli alcohol (PA) ameliorates hypertensive nephropathy in spontaneously hypertensive rats (SHR) and reveals potential mechanism.

METHODS

Briefly, the adult spontaneously hypertensive rats (SHR) or Wistar-Kyoto (WKY) rats (half male and half female) were intragastric gavaged or not with PA (80, 40 and 20 mg/kg) for 8 weeks. Body weight, blood pressure (BP), renal weight, renal function and renal morphology were measured. Further, western blotting and immunohistochemical analysis were used to study the underlying mechanism.

KEY FINDINGS

Compared with the WKY group, plasmatic levels of renin, angiotensin II (Ang-II), transforming growth factor beta 1(TGF-β1), plasminogen activator inhibitor-1(PAI-1), creatinine (Cr), blood urea nitrogen (BUN), renal index, mRNA levels of ERK1/2 and α-SMA were significantly increased in SHR. Histology results showed that renal tubular injury and tubulointerstitial fibrosis occurred in SHR. After administration, SBP of captopril group decreased at each week after administration, especially at 3, 5, 6 7 and 8 weeks (P < 0.05 or P < 0.01). There is no significant effect was assessed in the olive oil group. Decreased plasma Cr, Renin, Ang-II, TGF-β1, PAI-1, SCFAs and Renin, TGF-β1, PAI-1 in renal tissues were observed significantly in captopril (P <0.05 or P < 0.01). Plasma BUN, Ang-II, TGF-β1 and PAI-1 in renal tissues decreased in the olive oil group significantly (P <0.05 or P < 0.01). PA (80, 40 and 20 mg/kg) lowered BP and plasmatic levels of Renin, Ang-II, TGF-β1 and PAI-1. Treatment with PA (40, 20 mg/kg) decreased levels of Cr, BUN and suppressed of activation of pro-fibrosis cytokines including TGF-β1 in kidney. There is no ameliorative change in the olive oil group and the captopril group (P > 0.05) while PA treatment alleviated renal tubular injury and produced dramatic collagen fibre area reductions in mesangial membrane, basement membrane, and renal interstitium obviously (P < 0.05 or P < 0.01). Treatment of SHR with PA-inhibited MFB activation and downregulated mRNA of α-SMA. Treatment with PA suppressed excessive production of the extracellular matrix (ECM) via decreasing Col I, III and FN, downregulating mRNA of tissue inhibitor of TIMP-1 along with upregulating mRNA of MMP-9. The expression of Col III and MMP-9 mRNA-reduced in the captopril group (P < 0.05). In addition, the expression of ERK1/2 and pERK1/2 also reduced in the captopril group significantly (P < 0.05 or P < 0.01). Treatment with PA (20 mg/kg) downregulated proteins expression of Raf-1, ERK1/2 and pERK1/2 and mRNA expression of Ras, Raf-1 and ERK1/2.

CONCLUSIONS

Overall, PA restored normal BP, alleviated renal dysfunction and renal fibrosis, possibly by suppressing Ang II and TGF-β1-mediated Ras/Raf-1/ERK1/2 signalling pathway.

Bee Pollen as Functional Food: Insights into Its Composition and Therapeutic Properties

Bee pollen is a hive product made up of flower pollen grains, nectar, and bee salivary secretions that beekeepers can collect without damaging the hive. Bee pollen, also called bee-collected pollen, contains a wide range of nutritious elements, including proteins, carbs, lipids, and dietary fibers, as well as bioactive micronutrients including vitamins, minerals, phenolic, and volatile compounds. Because of this composition of high quality, this product has been gaining prominence as a functional food, and studies have been conducted to show and establish its therapeutic potential for medical and food applications. In this context, this work aimed to provide a meticulous summary of the most relevant data about bee pollen, its composition—especially the phenolic compounds—and its biological and/or therapeutic properties as well as the involved molecular pathways.

Possible protective effect of zinc administration on renal and cognitive changes occurring in uninephrectomized adult male Wistar rats

NEW FINDINGS

What is the central question of this study? Are renal changes occurring post-nephrectomy accompanied by cognitive changes, and does early administration of zinc supplements such as ZnSO4 to uninephrectomized rats ameliorate the renal and cognitive changes if present? What is the main finding and its importance? Uninephrectomy-induced renal changes were accompanied by species-atypical behaviour in rats in both Morris water maze and T maze tests, together with hypozincaemia and hippocampal inflammatory and oxidative changes. Early zinc administration to uninephrectomized rats ameliorated the renal, behavioural, hippocampal and serum zinc changes.

ABSTRACT

Cognitive impairment is increasingly recognized as an important consequence of kidney disease in humans. Kidney donation is a safe procedure but is known to increase the long-term risk of cardiovascular and kidney disease. Whether kidney donation impairs cognitive function is not known. In the present study, we examined whether the renal changes occurring post-nephrectomy were accompanied by cognitive changes as well, and whether early administration of zinc supplements such as ZnSO4 to uninephrectomized (UNX) rats could ameliorate the renal and cognitive changes if present. The present study included 30 adult male Wistar rats that were randomly assigned to three groups (n = 10 per group): sham-operated rats, UNX and UNX treated with ZnSO4 for 20 weeks. Before termination, rats were subjected to 24-h urine collection and behavioural testing with the Morris water maze and T maze tests. UNX induced significant proteinuria, renal functional, fibrotic and oxidative changes, as well as increased renal desmin expression. UNX rats also showed significant behavioural changes indicating spatial learning and memory affection, together with decreased hippocampal brain derived neurotrophic factor (BDNF) and antioxidant capacity, and increased glial fibrillary acidic protein (GFAP), nitric oxide and malondialdehyde. In addition, UNX induced significant hyperglycaemia and dyslipidaemia, as well as significant reduction in serum zinc, copper and selenium. Early administration of ZnSO4 starting 1 week post-nephrectomy significantly ameliorated renal and behavioural changes, as well as hippocampal oxidative, BDNF and GFAP changes. Additionally, Zn recovered serum changes of triglycerides, cholesterol, zinc and copper. Therefore, early administration of zinc to humans undergoing nephrectomy may be of benefit and should be considered in human trials.

Gastrodin attenuates renal injury and collagen deposition via suppression of the TGF-β1/Smad2/3 signaling pathway based on network pharmacology analysis

Background: Gastrodin has been widely used clinically in China as an antihypertensive drug. However, its effect on hypertensive renal injury is yet to be elucidated. The current study aimed to investigate the effects of gastrodin on hypertensive renal injury and its underlying mechanisms by network pharmacology analysis and validation in vivo and in vitro. Methods: A total of 10 spontaneously hypertensive rats (SHRs) were randomly categorized into the following two groups: SHR and SHR + Gastrodin groups. Wistar Kyoto (WKY) rats were used as the control group (n = 5). The SHR + Gastrodin group was intragastrically administered gastrodin (3.5 mg/kg/day), and the rats in both WKY and SHR groups were intragastrically administered an equal amount of double-distilled water for 10 weeks. Hematoxylin-eosin, Masson's trichrome, and Sirius red staining were used to detect the pathological changes and collagen content in the renal tissues. Network pharmacology analysis was performed to explore its potential targets and related pathways. In vitro, the CCK-8 assay was used to determine the cell viability. Immunohistochemistry and western-blotting analyses were employed to assess the protein expression associated with renal fibrosis and transforming growth factor-β1 (TGF-β1) pathway-related proteins in the renal tissues or in TGF-β1-stimulated rat kidney fibroblast cell lines (NRK-49F). Results: Gastrodin treatment attenuates renal injury and pathological alterations in SHRs, including glomerular sclerosis and atrophy, epithelial cell atrophy, and tubular dilation. Gastrodin also reduced the accumulation of collagen in the renal tissues of SHRs, which were confirmed by downregulation of α-SMA, collagen I, collagen III protein expression. Network pharmacology analysis identified TGFB1 and SMAD2 as two of lead candidate targets of gastrodin on against hypertensive renal injury. Consistently, gastrodin treatment downregulated the increase of the protein expression of TGF-β1, and ratios of both p-Smad2/Smad2 and p-Samd3/Smad3 in renal tissues of SHRs. In vitro, gastrodin (25-100 μM) treatment significantly reversed the upregulation of α-SMA, fibronectin, collagen I, as well as p-Smad2 and p-Smad3 protein expressions without affecting the cell viability of TGF-β1 stimulated NRK-49F cells. Conclusion: Gastrodin treatment significantly attenuates hypertensive renal injury and renal fibrosis and suppresses TGF-β1/Smad2/3 signaling in vivo and in vitro.

Identifying of miRNA–mRNA Regulatory Networks Associated with Acute Kidney Injury by Weighted Gene Co-Expression Network Analysis

Background

Acute kidney injury (AKI) is a clinical emergency characterized by a dramatic decline in renal function and the accumulation of metabolic waste products in the body, with a high morbidity and mortality rate. The pathogenesis of AKI remains unclear and there are no effective treatment options.

Methods

We aimed to identify critical genes involved in the pathogenesis of AKI and construct a miRNA–mRNA regulatory network using gene expression data downloaded from Gene Expression Omnibus (GSE85957) for 38 kidneys of AKI and 19 control rats and cisplatin treated kidneys of 3 AKI and 3 control rats. Data in GSE85957 were processed using weighted gene co-expression network analysis (WGCNA), and biological function analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were used to analyze the functions associated with critical genes.

Results

Twenty-eight modules in the GSE85957 dataset were identified by WGCNA, of which 103 genes in the orange module and 30 genes in the black module were closely associated with AKI and dose. Biological function analysis of genes in the orange and black modules revealed that skeletal muscle cell differentiation, tissue development and organ development were involved in the pathological changes of AKI. Combining with our experimentally processed AKI rat kidney data, eight genes (Atf3, Egr1, Egr2, Fos, Fosb, Gdf15, Serpine1 and Nr1d1) were identified as potential biomarkers of AKI, and miRNA–mRNA regulatory networks were constructed based on the above eight critical genes. Further tissue validation revealed that Egr1 and Fos were highly expressed in AKI.

Conclusion

Our study identified potential biomarkers of AKI and constructed an associated miRNA–mRNA regulatory network, which may provide new insights into the molecular pathogenesis of AKI.

Polyphenol-Rich Extract from Litchi chinensis Seeds Alleviates Hypertension-Induced Renal Damage in Rats

Litchi chinensis seed is a valuable byproduct of the subtropical fruit litchi (L. chinensis Sonn.), whose extract (LSE) has been confirmed to ameliorate dyslipidemia, hyperglycemia, and oxidative stress caused by type 2 diabetes. However, if LSE exerts an effect on anti-hypertension and hypertensive renal damage remains unknown. In this study, 13 polyphenols and one fatty acid were identified by UPLC-Q/TOF-MS. Network pharmacological analysis revealed that the therapeutic effects of LSE may be involved in multitargets and multipathways, such as the TNF signaling pathway, interleukin (IL)-6-mediated signaling pathway, NF-kappa B signaling pathway, removal of superoxide radicals, negative regulation of blood pressure, and so forth. Moreover, spontaneously hypertensive rats (SHRs) were daily gavaged with LSE (60 mg/kg) for 10 weeks. LSE remarkably reduced systolic blood pressure (SBP). The hypertension-induced renal damage was improved by suppressing inflammation and oxidative stress, which was consistent with the prediction of network pharmacology. In addition, LSE treatment remarkably increased the relative abundances of Lactobacillus and the production of short-chain fatty acids in the intestine. Our study indicated that a byproduct of litchi, namely, litchi seed, may be effective in reducing SBP and alleviating hypertensive renal damage.

An updated pharmacological insight of resveratrol in the treatment of diabetic nephropathy

As one of the most common complications of diabetes, nephropathy develops in approximately 40% of diabetic individuals. Although end stage kidney disease is known as one of the most consequences of diabetic nephropathy, the majority of diabetic individuals might die from cardiovascular diseases and infections before renal replacement treatment. Moreover, the routine medical treatments for diabetes hold undesirable side effects. The explosive prevalence of diabetes urges clinicians and scientists to investigate the complementary or alternative therapies. Phytochemicals are emerging as alternatives with a wide range of therapeutic effects on various pathologies, including diabetic kidney disease. Of those phytochemicals, resveratrol, a natural polyphenolic stilbene, has been found to exert a broad spectrum of health benefits via various signaling molecules. In particular, resveratrol has gained a great deal of attention because of its anti-oxidative, anti-inflammatory, anti-diabetic, anti-obesity, cardiovascular-protective, and anti-tumor properties. In the renal system, emerging evidence shows that resveratrol has already been used to ameliorate chronic or acute kidney injury. This review critically summarizes the current findings and molecular mechanisms of resveratrol in diabetic renal damage. In addition, we will discuss the adverse and inconsistent effects of resveratrol in diabetic nephropathy. Although there is increasing evidence that resveratrol affords great potential in diabetic nephropathy therapy, these results should be treated with caution before its clinical translation. In addition, the unfavorable pharmacokinetics and/or pharmacodynamics profiles, such as poor bioavailability, may limit its extensive clinical applications. It is clear that further research is needed to unravel these limitations and improve its efficacy against diabetic nephropathy. Increasing investigation of resveratrol in diabetic kidney disease will not only help us better understand its pharmacological actions, but also provide novel potential targets for therapeutic intervention.

The potential role of mast cells and fibroblast growth factor-2 in the development of hypertension-induced renal damage

Hypertension-induced renal injury is a multifactorial process which plays a crucial role in the development of chronic kidney disease. Multiple studies have demonstrated that interstitial rather than glomerular changes correlate better with renal functional capacity. Recent evidence indicates that mast cells and cell signaling proteins such as fibroblast growth factor-2 may contribute to the progression of interstitial changes under hypertensive conditions. The aim of our study was to determine the localization of mast cells in the renal cortex and report on the changes in their number, to analyze the distribution of fibroblast growth factor-2, to assess the extent of renal fibrosis and to evaluate renal damage and correlate it with the changes in the number of mast cells in a model of hypertension-induced renal injury by comparing two age groups of spontaneously hypertensive rats. We used 6- and 12-month-old animals. A light microscopic study was conducted on sections stained with hematoxylin and eosin, periodic acid-Schiff stain, Mallory's trichrome method and toluidine blue. For the immunohistochemical study we used monoclonal antibodies against mast cell tryptase and fibroblast growth factor-2 and a polyclonal antibody against c-kit. The expression of fibroblast growth factor-2 was assessed semi-quantitatively. The number of mast cells was evaluated on toluidine blue-, tryptase- and c-kit-stained sections, as well as double-stained sections and a comparative statistical analysis with the Mann-Whitney test was conducted between the two age groups. Our results showed that mast cells were located mainly in the peritubular and perivascular areas and were absent in the region of the renal corpuscles. Their number increased significantly in 12-month-old animals. Immunostaining for tryptase, c-kit and double staining for both molecules yielded identical results. The immunohistochemical expression of fibroblast growth factor-2 increased in the kidneys of older animals, as did the percentage of collagen fibers. In addition, we described more severe renal damage in 12-month-old spontaneously hypertensive rats and noted a positive correlation in both age groups between the number of mast cells on the one hand and glomerular sclerosis index and tubulointerstitial damage index, on the other. The results obtained in the present study support the pivotal role of mast cells in the development of hypertension-induced kidney damage.

Effects of resveratrol on the inflammatory response and renal injury in hyperuricemic rats

BACKGROUND/OBJECTIVES

Hyperuricemic nephropathy is a common cause of acute kidney injury. Resveratrol can ameliorate kidney injury, but the explicit mechanism remains unclear. We investigated the effects of resveratrol on the inflammatory response and renal injury in hyperuricemic rats.

MATERIALS/METHODS

A rat model of hyperuricemic nephropathy was established by the oral administration of a mixture of adenine and potassium oxinate. Biochemical analysis and hematoxylin and eosin staining were performed to assess the rat kidney function. Enzyme-linked immunosorbent assays were performed to evaluate the immune and oxidative responses.

RESULTS

The expression levels of urine albumin and β2-microglobulin were significantly decreased after resveratrol treatment. In addition, the levels of serum creatinine and uric acid were significantly decreased in the resveratrol groups, compared with the control group. The levels of proinflammatory factors, such as interleukin-1β and tumor necrosis factor-α, in kidney tissue and serum were also increased in the hyperuricemic rats, and resveratrol treatment inhibited their expression. Moreover, the total antioxidant capacity in kidney tissue as well as the superoxide dismutase and xanthine oxidase levels in serum were all decreased by resveratrol treatment.

CONCLUSIONS

Resveratrol may protect against hyperuricemic nephropathy through regulating the inflammatory response.

Hirudin Ameliorates Renal Interstitial Fibrosis via Regulating TGF-β1/Smad and NF-κB Signaling in UUO Rat Model

Purpose

Hirudin, a polypeptide structure containing 65 amino acids, is a potent natural thrombin inhibitor with anticoagulant property extracted from Hirudo medicinalis. It has been reported to have anti-inflammatory and antifibrotic property. Here we explored the renoprotective effect of hirudin on unilateral ureteral obstruction (UUO) induced renal interstitial fibrosis (RIF).

Methods

Rats were randomly divided into five groups: sham group, UUO alone group, and three UUO + hirudin-treatment groups (10, 20, or 40 IU/kg/d, for 14 continuous days). At the end of the experiment period, animals were sacrificed. Pathologic changes in renal specimens were observed using hematoxylin and eosin (HE) staining and Masson staining. The expressions of collagen III (Col III), fibronectin (FN), α-smooth muscle actin (α-SMA), protease-activated receptor 1 (PAR-1), and proteins in the TGF-β1/Smad and NF-κB pathways in renal tissues were examined by immunohistochemistry and/or Western blotting.

Results

HE and Masson staining showed that hirudin-treated UUO rats had lower extent of renal injury and deposition of extracellular matrix (ECM) in renal interstitium than those in the UUO group. The results of immunohistochemistry and WB indicated decreased protein expressions of Col III, FN, α-SMA, PAR-1, and inflammatory markers such as tumor necrosis factor-α and interleukin-6 after hirudin treatment. Furthermore, hirudin reduced the expressions of transforming growth factor β1 (TGF-β1), phosphorylated-Smad2, and phosphorylated-Smad3 in the UUO model. In parallel, we found inhibited nuclear factor-κB (NF-κB) signaling after hirudin treatment, with downregulated protein expressions of P65, phosphorylated-P65, and phosphorylated-iκBα and increased iκBα.

Conclusion

Hirudin improves kidney injury and suppresses inflammatory response and ECM accumulation in UUO rats; its underlying mechanism may be associated with the inhibition of TGF-β1/Smad and NF-κB signaling.

Diuretic and Renal Protective Effect of Kaempferol 3-O-Alpha-l-rhamnoside (Afzelin) in Normotensive and Hypertensive Rats

Our previous study showed that kaempferitrin, the main flavonoid from Bauhinia forficata Link leaves, induces diuresis and saluresis when orally given to rats. Since afzelin (AFZ) and kaempferol (KFL) are active compounds from the biometabolism of kaempferitrin, the diuretic and renal protective properties of these two compounds were evaluated. While the acute treatment with AFZ evoked a diuretic action associated with an increase in Cl^- excretion and a Ca²⁺-sparing effect, KFL did not present any activity. The pretreatment with a muscarinic receptor blocker or with an inhibitor of the cyclooxygenase fully avoided AFZ-induced diuresis. AFZ also induced a prolonged (7-day treatment) diuretic effect in normotensive (NTR) and hypertensive rats (SHR), with an increase of urinary Na⁺ and Cl^- excretion, while it decreased the elimination of Ca²⁺. AFZ was able to decrease ROS and nitrite generation on kidney homogenates in comparison with the SHR group treated with the vehicle, as well as mitigated the changes in the renal corpuscle region (glomerulus and Bowman's capsule). Moreover, AFZ significantly reduced calcium oxalate crystal formation in urine, with inhibition rates of 41% for the NTR and 92% for the SHR group. Taken together, this study shows that AFZ exerts acute and prolonged diuretic effects plus protective renal properties.

Adipose Mesenchymal Cells-Derived EVs Alleviate DOCA-Salt-Induced Hypertension by Promoting Cardio-Renal Protection

Hypertension is a long-term condition that can increase organ susceptibility to insults and lead to severe complications such as chronic kidney disease (CKD). Extracellular vesicles (EVs) are cell-derived membrane structures that participate in cell-cell communication by exporting encapsulated molecules to target cells, regulating physiological and pathological processes. We here demonstrate that multiple administration of EVs from adipose-derived mesenchymal stromal cells (ASC-EVs) in deoxycorticosterone acetate (DOCA)-salt hypertensive model can protect renal tissue by maintaining its filtration capacity. Indeed, ASC-EVs downregulated the pro-inflammatory molecules monocyte chemoattracting protein-1 (MCP-1) and plasminogen activating inhibitor-1 (PAI1) and reduced recruitment of macrophages in the kidney. Moreover, ASC-EVs prevented cardiac tissue fibrosis and maintained blood pressure within normal levels, thus demonstrating their multiple favorable effects in different organs. By applying microRNA (miRNA) microarray profile of the kidney of DOCA-salt rats, we identified a selective miRNA signature associated with epithelial-mesenchymal transition (EMT). One of the key pathways found was the axis miR-200-TGF-β, that was significantly altered by EV administration, thereby affecting the EMT signaling and preventing renal inflammatory response and fibrosis development. Our results indicate that EVs can be a potent therapeutic tool for the treatment of hypertension-induced CKD in cardio-renal syndrome.

Resveratrol improves left ventricular remodeling in chronic kidney disease via Sirt1-mediated regulation of FoxO1 activity and MnSOD expression

Left ventricular remodeling commonly complicates end-stage renal disease following chronic kidney disease (CKD). This study investigated the therapeutic efficacy of resveratrol (RSV), a polyphenolic compound, on left ventricular remodeling in subtotal nephrectomy rats and sought to uncover the underlying molecular mechanisms. Subtotal nephrectomy caused renal dysfunction, such as gradual increases in serum creatinine and blood urea nitrogen, glomerular sclerosis, and tubulointerstitial fibrosis. In addition, subtotal nephrectomy also resulted in significant increases in myocyte cross-sectional area, interstitial and perivascular fibrosis, and left ventricular dilatation. All these detrimental effects were alleviated in the presence of RSV. Mechanistically, RSV treatment led to the upregulation of manganese-containing superoxide dismutase (MnSOD) in the heart. Coimmunoprecipitation studies showed that silent information regulator 1 (Sirt1) bound forkhead box protein O1 (FoxO1) and thus reduced acetylated FoxO1. RSV strengthened this interaction between Sirt1 and FoxO1. Loss of one allele of Sirt1 aggravated renal damage, myocyte hypertrophy, and interstitial fibrosis in nephrectomized mice. Taken together, our data show that Sirt1 is an important mediator for the protective roles of RSV on renal and heart damage in CKD rodent model, and FoxO1 and MnSOD are likely downstream targets of Sirt1. Therefore, Sirt1 might be a potential therapeutic target for the treatment of left ventricular remodeling caused by CKD.

miRNA‑mRNA regulatory network analysis of mesenchymal stem cell treatment in cisplatin‑induced acute kidney injury identifies roles for miR‑210/Serpine1 and miR‑378/Fos in regulating inflammation

The present study aimed to identify microRNAs (miRNAs) that may be crucial for the mechanism of mesenchymal stem cell (MSC) treatment in cisplatin-induced acute kidney injury (AKI) and to investigate other potential drugs that may have a similar function. Transcriptomics (GSE85957) and miRNA expression (GSE66761) datasets were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) were identified using the linear models for microarray data method and mRNA targets of DEMs were predicted using the miRWalk2.0 database. The crucial DEGs were screened by constructing a protein-protein interaction (PPI) network and module analysis. Functions of target genes were analyzed using the database for annotation, visualization and integrated discovery. Small molecule drugs were predicted using the connectivity map database. As a result, 5 DEMs were identified to be shared and oppositely expressed in comparisons between AKI model and control groups, and between MSC treatment and AKI model groups. The 103 DEGs were overlapped with the target genes of 5 common DEMs, and the resulting list was used for constructing the miRNA-mRNA regulatory network, including rno-miR-210/Serpine1 and rno-miR-378/Fos. Serpine1 (degree=17) and Fos (degree=42) were predicted to be hub genes according to the topological characteristic of degree in the PPI network. Function analysis indicated Serpine1 and Fos may be inflammation-related. Furthermore, gliclazide was suggested to be a potential drug for the treatment of AKI because the enrichment score was the closest to −1 (−0.9). In conclusion, it can be speculated that gliclazide may have a similar mechanism to MSC as a potential therapeutic agent for cisplatin-induced AKI, by regulating miR-210/Serpine1 and miR-378-/Fos-mediated inflammation and cell apoptosis.

Remote transplantation of human adipose-derived stem cells induces regression of cardiac hypertrophy by regulating the macrophage polarization in spontaneously hypertensive rats

Left ventricular hypertrophy (LVH) in hypertension has prognostic significance on cardiovascular mortality and morbidity. Recently, we have shown that n-butylidenephthalide (BP) improves human adipose-derived stem cell (hADSC) engraftment via attenuated reactive oxygen species (ROS) production. This prompted us to investigate whether remote transplantation of BP-pretreated hADSCs confers attenuated LVH at an established phase of hypertension. Male spontaneously hypertensive rats (SHRs) aged 12 weeks were randomly allocated to receive right hamstring injection of vehicle, clinical-grade hADSCs, and BP-preconditioned hADSCs for 8 weeks. As compared with untreated SHRs, naïve hADSCs decreased the ratio of LV weight to tibia, cardiomyocyte cell size, and collagen deposition independent of hemodynamic changes. These changes were accompanied by attenuated myocardial ROS production and increased p-STAT3 levels. Compared with naïve hADSCs, BP-preconditioned hADSCs provided a further decrease of ROS and LVH and an increase of local hADSC engraftment, STAT3 phosphorylation, STAT3 activity, STAT3 nuclear translocation, myocardial IL-10 levels, and the percentage of M2 macrophage infiltration. SIN-1 or S3I-201 reversed the effects of BP-preconditioned ADSCs increase on myocardial IL-10 levels. Furthermore, SIN-1 abolished the phosphorylation of STAT3, whereas superoxide levels were not affected following the inhibition of STAT3. Our results highlighted the feasibility of remote transplantation of hADSCs can be considered as an alternative procedure to reverse cardiac hypertrophy even at an established phase of hypertension. BP-pretreated hADSCs polarize macrophages into M2 immunoregulatory cells more efficiently than naïve hADSCs via ROS/STAT3 pathway.

•

Hypertension was associated with left ventricular hypertrophy.

•

Compared with untreated SHRs, naïve hADSCs injected at the right hamstring decreased LV mass and cardiomyocyte cell size.

•

BP-preconditioned ADSCs provided a further increase of the M2 macrophage infiltration.

•

The beneficial effects of BP-preconditioned stem cell administration can be abolished by exogenous SIN-1 or 3SI-201.

•

Remote transplantation of hADSCs can be considered as an alternative procedure to reverse cardiac hypertrophy.

Clopidogrel Reduces Fibronectin Accumulation and Improves Diabetes-Induced Renal Fibrosis

Hyperglycemia-induced renal fibrosis causes end-stage renal disease. Clopidogrel, a platelet inhibitor, is often administered to decrease cardiovascular events in diabetic patients. We investigated whether clopidogrel can reduce diabetes-induced renal fibrosis in a streptozotocin-induced type 1 diabetes murine model and fibronectin involvement in this protective response. Diabetic and age-matched controls were sacrificed three months after the onset of diabetes, and additional controls and diabetic animals were further treated with clopidogrel or vehicle for three months. Diabetes induced renal morphological changes and fibrosis after three months. Clopidogrel, administered during the last three months, significantly decreased blood glucose, collagen and fibronectin expression compared to vehicle-treated diabetic mice. Diabetes increased TGF-β expression, inducing fibrosis via Smad-independent pathways, MAP kinases, and Akt activation at three months but returned to baseline at six months, whereas the expression of fibronectin and collagen remained elevated. Our results suggest that activation of TGF-β, CTGF, and MAP kinases are early profibrotic signaling events, resulting in significant fibronectin accumulation at the early time point and returning to baseline at a later time point. Akt activation at the three-month time point may serve as an adaptive response in T1D. Mechanisms of clopidogrel therapeutic effect on the diabetic kidney remain to be investigated as this clinically approved compound could provide novel approaches to prevent diabetes-induced renal disease, therefore improving patients' survival.

JYYS Granule Mitigates Renal Injury in Clinic and in Spontaneously Hypertensive Rats by Inhibiting NF-κB Signaling-Mediated Microinflammation

Introduction

Hypertensive renal damage is a chronic and life-threatening kidney disease all over the world. The traditional Chinese medicine Jiang Ya Yi Shen (JYYS) granule has been a perfect drug for patients with hypertensive renal injury in clinic for 20 years in China. However, the molecular mechanism of JYYS granule remains unknown in treatment of this disease.

Methods

The clinic data were from this study's patients. The clinical symptoms of patients were indicated by (N-Acetyl-β-D-Glucosaminidase) NAG, (albumin) Alb, and (β2-microglobin) β2-MG content in urinary of patients, and renal artery's hemodynamic parameters including (pulse index) PI, mean velocity of the arterial blood (Vm), minimum velocity of the diastolic stage (Vdmin) and peak velocity of the systolic wave (Vsmax). To further observe the effect of JYYS granule on renal damage, the rats were included in six groups: normal rats (WKY), spontaneously hypertensive rats (SHR), positive drug-treated rats (Benazepril), low dose JYYS (L), middle dose JYYS (M), and high dose JYYS (H). Then, we observed the effect of JYYS on renal function, renal tubules, inflammatory cell infiltration, and small artery thickening, and we explored the potential mechanism of JYYS in treatment of renal injury.

Results

JYYS significantly improved the clinic symptoms of patients with hypertensive nephropathy by downregulating NAG, Alb, and β2-MG content in urinary of patients and by decreasing renal artery's hemodynamic parameters including PI, Vm, Vdmin, and Vsmax. In SHR, JYYS significantly improved renal function including creatinine clearance rate, urinary albumin/creatinine, β2-MG/creatinine and arteria caudalis pressure in SHR. Secondly, light and electron microscopic examinations told that after administration of JYYS and Benazepril, the mesangial region exhibited no hyperplasia and renal capsule did not expanded, and there no abnormalities were observed in renal tubules, inflammatory cell infiltration and small artery thickening in SHR. Thirdly, JYYS exhibited its protective role by inhibiting nuclear factor kappa beta signaling-mediated micro-inflammation cytokines including interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), intercellular cell adhesion molecule-1 (ICAM-1), and monocyte chemotactic protein 1 (MCP-1) in SHR.

Conclusion

JYYS is a promising prescription of Chinese medicine for patients with hypertension and hypertensive renal damage.

A comprehensive review of the health perspectives of resveratrol

Many natural products present in our diet, including flavonoids, can prevent the progression of cancer and other diseases. Resveratrol, a natural polyphenol present in various fruits and vegetables, plays an important role as a therapeutic and chemopreventive agent used in the treatment of various illnesses. It exhibits effects against different types of cancer through different pathways. It additionally exerts antidiabetic, anti-inflammatory, and anti-oxidant effects in a variety of cell types. Furthermore, the cardiovascular protective capacities of resveratrol are associated with multiple molecular targets and may lead to the development of novel therapeutic strategies for atherosclerosis, ischemia/reperfusion, metabolic syndrome, and heart failure. Accordingly, this article presents an overview of recent developments in the use of resveratrol for the prevention and treatment of different diseases along with various mechanisms. In addition, the present review summarizes the most recent literature pertaining to resveratrol as a chemotherapeutic agent against multiple diseases and provides an assessment of the potential of this natural compound as a complementary or alternative medicine.

Diagnostic Value of Urinary Microalbumin Level in Postpartum Acute Kidney Injury

BACKGROUND

We aimed to explore the diagnostic value of urinary microalbumin (mALB) level in postpartum acute kidney injury.

METHODS

A total of 127 maternity patients were selected from December 2013 to January in 2016 in Binzhou Central Hospital, Binzhou, Shandong, China and divided into two groups: the kidney injury and normal kidney group. The dynamic changes and diagnostic value of urine microprotein in postpartum acute kidney injury were analyzed.

RESULTS

The postpartum mean arterial pressure of maternity patients in the kidney injury group was 104.3 ± 11.6 mmHg, which was significantly higher than that of the normal kidney group (P<0.05). The mean age of the kidney injury group was 32.3 ± 11.6 years, which was significantly higher than that of the normal kidney group (P=0.006). In the kidney injury group, the postpartum glomerular filtration rate (GFR) was 78.4 ± 11.5 mL/min, which was significantly lower than the normal group (P=0.001), and urinary microalbumin was 2.87 ± 1.24 mg/mmol·Cr. The difference was statistically significant (P=0.002). mALB/GFR, Cr, urinary mALB, and GFR were the independent risk factors of postpartum acute kidney injury. The area under the ROC curve for mALB/GFR was 0.759, whereas the area under the ROC curve for Cr was 0.681, which was smaller (P = 0.042). The area under the ROC curve of mALB was 0.785 (P=0.027), which was close to the area under the ROC curve of mALB/GFR.

CONCLUSION

Urinary mALB test is noninvasive and has high diagnostic value for postpartum kidney injury.

Anti-Renal Fibrotic Effect of Exercise Training in Hypertension

The purpose of this study was to evaluate the effects of exercise training on renal fibrosis in hypertensive rats. Masson's trichrome staining and Western blotting were performed on the excised renal cortex from sixteen male spontaneously hypertensive rats (SHR), which were randomly divided into either a sedentary hypertensive group (SHR) or exercise hypertensive group (SHR-EX, running on an exercise treadmill for 60 min/day, 5 sessions/week, for 12 weeks), and from eight male Wistar-Kyoto rats which served as a sedentary normotensive group (WKY). The systolic blood pressure (SBP) and renal fibrosis in hypertensive rats improved after exercise training. The inflammatory-related protein levels of interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2), as well as the fibrotic-related protein levels of transforming growth factor-beta (TGF-β), phospho-Smad2/3 (p-Smad2/3), connective tissue growth factor (CTGF), matrix metalloproteinase-9 (MMP-9), and matrix metalloproteinase-2 (MMP-2) were decreased in the SHR-EX group when compared with the SHR group. Exercise training suppressed the hypertension-induced renal cortical inflammatory and fibrotic pathways in hypertensive rat models. These findings might indicate a new therapeutic effect for exercise training to prevent renal fibrosis in hypertensive nephropathy.

BCL6 attenuates renal inflammation via negative regulation of NLRP3 transcription

Renal inflammation contributes to the pathogeneses of hypertension. This study was designed to determine whether B-cell lymphoma 6 (BCL6) attenuates renal NLRP3 inflammasome activation and inflammation and its underlying mechanism. Male spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) were used in the present study. Angiotensin (Ang) II or lipopolysaccharides (LPS) was used to induce inflammation in HK-2 cells, a human renal tubular epithelial (RTE) cell line. NLRP3 inflammasome was activated and BCL6 was downregulated in the kidneys of SHR. Either Ang II or LPS suppressed BCL6 expression in HK-2 cells. BCL6 overexpression in HK-2 cells attenuated Ang II-induced NLRP3 upregulation, inflammation and cell injury. The inhibitory effects of BCL6 overexpression on NLRP3 expression and inflammation were also observed in LPS-treated HK-2 cells. BCL6 inhibited the NLRP3 transcription via binding to the NLRP3 promoter. BCL6 knockdown with shRNA increased NLRP3 and mature IL-1β expression levels in both PBS- or Ang II-treated HK-2 cells but had no significant effects on ASC, pro-caspase-1 and pro-IL-1β expression levels. BCL6 overexpression caused by recombinant lentivirus expressing BCL6 reduced blood pressure in SHR. BCL6 overexpression prevented the upregulation of NLRP3 and mature IL-1β expression levels in the renal cortex of SHR. The results indicate that BCL6 attenuates Ang II- or LPS-induced inflammation in HK-2 cells via negative regulation of NLRP3 transcription. BCL6 overexpression in SHR reduced blood pressure, NLRP3 expression and inflammation in the renal cortex of SHR.

Recent Advances of Curcumin in the Prevention and Treatment of Renal Fibrosis

Curcumin, a polyphenol derived from the turmeric, has received attention as a potential treatment for renal fibrosis primarily because it is a relatively safe and inexpensive compound that contributes to kidney health. Here, we review the literatures on the applications of curcumin in resolving renal fibrosis in animal models and summarize the mechanisms of curcumin and its analogs (C66 and (1E,4E)-1,5-bis(2-bromophenyl) penta-1,4-dien-3-one(B06)) in preventing inflammatory molecules release and reducing the deposition of extracellular matrix at the priming and activation stage of renal fibrosis in animal models by consulting PubMed and Cnki databases over the past 15 years. Curcumin exerts antifibrotic effect through reducing inflammation related factors (MCP-1, NF-κB, TNF-α, IL-1β, COX-2, and cav-1) and inducing the expression of anti-inflammation factors (HO-1, M6PRBP1, and NEDD4) as well as targeting TGF-β/Smads, MAPK/ERK, and PPAR-γ pathways in animal models. As a food derived compound, curcumin is becoming a promising drug candidate for improving renal health.

Piceatannol Attenuates Renal Fibrosis Induced by Unilateral Ureteral Obstruction via Downregulation of Histone Deacetylase 4/5 or p38-MAPK Signaling

Piceatannol, a resveratrol metabolite, is a phenolic compound found in red wine and grapes. We investigated the effect of piceatannol on renal fibrosis and histone deacetylase (HDAC) expression in a mouse model of unilateral ureteral obstruction (UUO). Fibrosis was established by UUO and piceatannol was intraperitoneally injected for 2 weeks. Piceatannol suppressed extracellular matrix (ECM) protein deposition including collagen type I and fibronectin as well as connective tissue growth factor (CTGF) and α-smooth muscle actin (α-SMA) in UUO kidneys. However, the expressions of epithelial-mesenchymal transition (EMT) marker genes, such as N-cadherin and E-cadherin, were not changed in the kidneys after UUO. Masson’s trichrome staining and fluorescence immunostaining showed that piceatannol administration attenuated collagen deposition in UUO kidneys. HDAC1, HDAC4, HDAC5, HDAC6, and HDAC10 protein expression was upregulated in UUO kidneys, whereas that of HDAC8 was downregulated. Piceatannol treatment significantly reduced HDAC4 and HDAC5 protein expression. Further, piceatannol attenuated phosphorylation of p38 mitogen-activated protein kinase (p38-MAPK) in UUO kidneys, but not that of transforming growth factor beta1-Smad2/3. These results suggest that class I HDACs and class IIa/b HDACs are involved in renal fibrosis development. Piceatannol may be a beneficial therapeutic agent for treating renal fibrosis via reduction of HDAC4 and HDAC5 protein expression or suppression of the p38-MAPK signaling pathway.

Promiscuous Effects of Some Phenolic Natural Products on Inflammation at Least in Part Arise from Their Ability to Modulate the Expression of Global Regulators, Namely microRNAs

Recent years have seen the exploration of a puzzling number of compounds found in human diet that could be of interest for prevention or treatment of various pathologies. Although many of these natural products (NPs) have long been used as remedies, their molecular effects still remain elusive. With the advent of biotechnology revolution, NP studies turned from chemistry and biochemistry toward global analysis of gene expression. Hope is to use genetics to identify groups of patient for whom certain NPs or their derivatives may offer new preventive or therapeutic treatments. Recently, microRNAs have gained the statute of global regulators controlling cell homeostasis by regulating gene expression through genetic and epigenetic regulatory loops. Realization that certain plant polyphenols can modify microRNA expression and thus impact gene expression globally, initiated new, mainly in vitro studies, in particular to determine phytochemicals effects on inflammatory response, whose exacerbation has been linked to several disorders including cancer, auto-immune, metabolic, cardiovascular and neuro-inflammatory diseases. However, very few mechanistic insights have been provided, given the complexity of genetic regulatory networks implicated. In this review, we will concentrate on data showing the potential interest of some plant polyphenols in manipulating the expression of pro- and anti-inflammatory microRNAs in pathological conditions.