IgG4-related kidney disease complicated with retroperitoneal fibrosis:A case report

BACKGROUND IgG4-related disease(IgG4-RD)is a chronic fibrotic disease mediated by immunity recognized by clinicians in recent years.When the kidney is involved,it is called IgG4-related kidney disease(IgG4-RKD).IgG4-related tubulointerstitial nephritis(IgG4-TIN)is a representative manifestation of IgG4-RKD.IgG4-TIN can cause obstructive nephropathy complicated by retroperitoneal fibrosis(RPF).Cases of IgG4-TIN complicated with RPF are rare.Glucocorticoids are the firstline therapeutic medication for IgG4-RD and can significantly improve renal function.CASE SUMMARY Herein,we report the case of a 56-year-old man with IgG4-RKD complicated with RPF.The patient presented to the hospital with complaints of elevated serum creatinine(Cr),nausea,and vomiting.During hospitalization,Cr was 1448.6μmol/L,and serum IgG4 was increased.A total abdominal computed tomography(CT)scan and enhanced CT scan obviously indicated RPF.Although this patient had a long course and renal insufficiency,we performed a kidney biopsy.Renal biopsy showed that the renal tubulointerstitium had focal plasma cell infiltration and increased lymphocyte infiltration accompanied by fibrosis.After combining the biopsy results with immunohistochemistry,it was found that the absolute number of positive IgG4+cells per high power field exceeded 10,and the ratio of IgG4/IgG was over 40%.Finally,the patient was diagnosed with IgG4-TIN complicated with RPF and given glucocorticoids as long-term maintenance therapy,helping him keep out of dialysis.After a follow-up of 19 mo,the patient had recovered well.Previous literature on IgG4-RKD and RPF was retrieved from PubMed to characterize the clinical and pathological features and to identify the diagnosis and treatment of IgG4-RKD.CONCLUSION Our case report demonstrates the clinical characteristics of IgG4-RKD complicated with RPF.Serum IgG4 is a favorable indicator for screening.Performing renal biopsy actively plays a vital role in diagnosis and treatment,even if the patient has a long course and manifests with renal insufficiency.It is remarkable to treat IgG4-RKD with glucocorticoids.Hence,early diagnosis and targeted therapy are essential for reversing renal function and improving extrarenal manifestations in patients with IgG4-RKD.

Matrix metalloproteinases contribute to kidney fibrosis in chronic kidney diseases

Matrix metalloproteinases(MMPs) are members of the neutral proteinase family. They were previously thought to be anti-fibrotic because of their ability to degrade and remodel of extracellular matrix. However, recent studies have shown that MMPs are implicated in initiation and progression of kidney fibrosis through tubular cell epithelial–mesenchymal transition(EMT) as well as activation of resident fibroblasts, endothelial-mesenchymal transition(Endo MT) and pericyte-myofibroblast transdifferentiation. Interstitial macrophage infiltration has also been shown to correlate with the severity of kidney fibrosis in various chronic kidney diseases. MMPs secreted by macrophages, especially MMP-9, hasbeen shown by us to be profibrotic by induction of tubular cells EMT. EMT is mainly induced by transforming growth factor-β(TGF-β). However, MMP-9 was found by us and others to be up-regulated by TGF-β1 in kidney tubular epithelial cells and secreted by activated macrophages, resulting in EMT and ultimately kidney fibrosis. Therefore, MMP-9 may serve as a potential therapeutic target to prevent kidney fibrosis in chronic kidney disease. This review, by a particular focus on EMT, seeks to provide a comprehensive understanding of MMPs, especially MMP-9, in kidney fibrosis.

Unique interstitial miRNA signature drives fibrosis in a murine model of autosomal dominant polycystic kidney disease

AIM To delineate changes in miRNA expression localized to the peri-cystic local microenvironment(PLM) in an orthologous mouse model of autosomal dominant polycystic kidney disease(ADPKD)(mcwPkd1^(nl/nl)).METHODS We profiled miRNA expression in the whole kidney and laser captured microdissection(LCM) samples from PLM in mcwPkd1^(nl/nl)kidneys with Qiagen miScript 384 HC miRNA PCR arrays. The three times points used are:(1) post-natal(PN) day 21, before the development of trichrome-positive areas;(2) PN28, the earliest sign of trichrome staining; and(3) PN42 following the development of progressive fibrosis. PN21 served as appropriate controls and as the reference time point for comparison of miRNA expression profiles.RESULTS LCM samples revealed three temporally upregulated miRNAs [2 to 2.75-fold at PN28 and 2.5 to 4-fold(P ≤ 0.05) at PN42] and four temporally downregulated miRNAs [2 to 2.75 fold at PN28 and 2.75 to 5-fold(P ≤ 0.05) at PN42]. Expression of twenty-six miRNAs showed no change until PN42 [six decreased(2.25 to 3.5-fold)(P ≤ 0.05) and 20 increased(2 to 4-fold)(P ≤ 0.05)]. Many critical miRNA changes seen in the LCM samples from PLM were not seen in the contralateral whole kidney.CONCLUSION Precise sampling with LCM identifies miRNA changes that occur with the initiation and progression of renal interstitial fibrosis(RIF). Identification of the target proteins regulated by these miRNAs will provide new insight into the process of fibrosis and identify unique therapeutic targets to prevent or slow the development and progression of RIF in ADPKD.

Predicting outcomes after kidney transplantation: Can Pareto’s rules help us to do so?

Kidney transplantation is the best option for kidney replacement therapy,even considering that most of the times the grafts do not survive as long as their recipients.In the Khalil et al's experience,published in this issue of the Journal,they analyze their second kidney graft survival and describe those significant predictors of early loss.This editorial comments on the results and put in perspective that most of the times,long-term graft survival could be inadvertently jeopardized if the immunosuppressive therapy is reduced or withdrawn for any reason,and that it could happen frequently if the transplant physician intends to innovate with the clinical care without proper evidence-based data.

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.

Progress in drug delivery system for fibrosis therapy

Fibrosis is a necessary process in the progression of chronic disease to cirrhosis or even cancer,which is a serious disease threatening human health.Recent studies have shown that the early treatment of fibrosis is turning point and particularly important.Therefore,how to reverse fibrosis has become the focus and research hotspot in recent years.So far,the considerable progress has been made in the development of effective anti-fibrosis drugs and targeted drug delivery.Moreover,the existing research results will lay the foundation for more breakthrough delivery systems to achieve better anti-fibrosis effects.Herein,this review summaries anti-fibrosis delivery systems focused on three major organ fibrotic diseases such as liver,pulmonary,and renal fibrosis accompanied by the elaboration of relevant pathological mechanisms,which will provide inspiration and guidance for the design of fibrosis drugs and therapeutic systems in the future.

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

This study aimed to explore the protective effects of the traditional Chinese Medicine formula Shenkang Ⅶ recipe(SK-7)on renal fibrosis and the mechanisms.Renal fibrosis was induced by unilateral ureteral obstruction(UUO)in rats.The rats were then divided into 5 groups:control group(Sham operation),UUO model group,UUO model plus low to high doses of SK-7(0.5,1.0,or 2.0 g/kg/day,for 14 days)groups.The animals were sacrificed on the 7th or 14th day.K idney tissues were collected for histopathological exarminations(hematoxylin and cosin and Masson's trichrome staining).Immunohistochemistry was used to detect the expression of collagen type II(Col II),fibronectin(FN),α-smooth muscle actin(a-SMA),TIMP metallopeptidase inhibitor 2(TIMP2),matrix metallopeptidase 2(MMP2),tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β)and monocyte chemotactic protein-1(MCP-1).The TGF-β1/Smad,NF-κB and Sonic hedgehog signaling proteins were detected by Western blotting.Our results showed that SK-7 prevented UUO-induced renal injury and accumulation of collagen fibrils.Renal fbrosis biomarkers Col Ⅲ,FN,α-SMA and TMP2 were increased in the rats after UUO and decreased by SK-7,while MMP2 was upregulated after treatment.SK-7 also suppressed the levels of TNF-α,IL-1βand MCP-1 in UUO rats.In addition,SK-7 inhibited activation of the TGF-B/Smad,NF-κB and sonic hedgehog signaling(SHH)pathways.Taken together,these findings suggest that SK-7 may regulate the synthesis and degradation of extracellular matrix,reduce inflammation and suppress the proliferation of fibroblasts,by blocking the TGF-β1/Smad,NF-κB and SHH signaling pathways to exert its anti-renal fbrosis effect in UUO rats.

Nephrogenic systemic fibrosis:A frivolous entity

Gadolinium-based contrast agents(GBCAs)used in magnetic resonance imaging are vital in providing enhanced quality images,essential for diagnosis and treatment.Nephrogenic systemic fibrosis(NSF)with GBCAs has been a deterrent for the physician and has led to avoidance of these agents in patients with impaired kidney function.NSF is a progressive debilitating multisystem condition described classically in patients with renal insufficiency exposed to gadolinium contrast media.It is characterized by an induration and hardening of the skin.NSF is described to first involve the extremities and can imperceptibly involve internal organs.Lack of therapeutic interventions to treat NSF makes it more challenging and warrants deep insight into the pathogenesis,risk factors and treatment strategies.

Anti-fibrotic and anti-inflammatory effect of mesenchymal stromal cell-derived extracellular vesicles in chronic kidney disease

Renal fibrosis and inflammation are common pathological features of chronic kidney disease(CKD).Since currently available treatments can only delay the progression of CKD,the outcome of patients with CKD is still poor.One therapeutic option for the prevention of CKD-related complications could be the use of mesenchymal stromal cells(MSCs),which have shown beneficial effects in tissue fibrosis and regeneration after damage.However,safety issues,such as cellular rejection and carcinogenicity,limit their clinical application.Among the bioactive factors secreted by MSCs,extracellular vesicles(EVs)have shown the same beneficial effect of MSCs,without any notable side effects.This heterogeneous population of membranous nano-sized particles can deliver genetic material and functional proteins to injured cells,prompting tissue regeneration.Here we describe the anti-fibrotic and antiinflammatory properties of MSC-derived EVs in CKD preclinical models and summarize the potential molecular mechanisms involved in the regulation of renal fibrosis and inflammation.

Z-Guggulsterone alleviated renal fibrosis and G_(2)/M cycle arrest through Klotho/P53 signaling

OBJECTIVE Chronic kidney disease(CKD)has become a global public health problem with 10%-15%incidence rate,and inhibiting the renal interstitial fibrosis is considered to be a potential strategy to delay the progression of CKD.Z-Guggulsterone(Z-GS),an active compound from derived from Commiphora mukul,has been proved to be effective in various diseases.The present study aimes to determine the protective effect and the molecular mechanism of Z-GS on renal fibrosis.METHODS Unilateral ureteral obstruction(UUO)mice and hypoxia-induced HK-2 cells were used to simulate renal fibrosis in vitro and in vivo,respectively.The mice and cells were treated with different doses of Z-GS to observe the pharmacological action.Renal function,including Scr,BUN,and UA,were detected by commercial kits.H&E and Masson staining were performed to observe histopathological changes of kidney.Cell viability and LDH release of HK-2 cells were detected by commercial kits.Cell cycle distribution and apoptosis rate were analyzed by flow cytometry.Fibrosis markers were detected by immunohistochemistry and immunofluorescence analysis.Cell cycle related proteins and Klotho/p53 signaling were analyzed by Western blotting.RESULTS The results showed that Z-GS decreased the rise of Scr,BUN,and UA and lightened renal histopathological injury,which were induced by UUO.Besides,Z-GS administration alleviated renal fibrosis in mice by inhibiting the expressions ofα-SMA,TGF-βand collagenⅣ,and delayed G2/M cell cycle arrest by promoting the expressions of CDK1 and cyclinD1/B1 rate.Experiments in vitro indicated that Z-GS treatment significantly increased the cell viability while decreased the LDH release in hypoxia-induced HK-2 cells.In addition,hypoxia induced fibrosis and G2/M cycle arrest in HK-2 cells were retarded by Z-GS.The study of its possible mechanism exhibited that Z-GS treatment increased the level of Klotho and inhibited P53 level.Nevertheless,the effect of Z-GS on Klotho/P53 signaling was reversed by siRNA-Klotho.Moreover,siRNA-Klotho treatment eliminated the effects of Z-GS on G2/M cell cycle arrest and fibrosis.CONCLUSION This study clarified that Z-GS alleviated renal fibrosis and G2/M cycle arrest through Klotho/P53 signaling pathway.People who have suffered CKD may potentially benefit from treatment with Z-GS.

ELABELA protects against diabetic kidney disease by activating high glucose-inhibited renal tubular autophagy

ELABELA(ELA),an endogenous ligand of the apelin receptor(also known as apelin peptide jejunum[APJ]),has been shown to decrease in the plasma of patients with diabetic kidney disease(DKD).In the current study,we explored the potential function as well as the underlying mechanisms of ELA in DKD.We first found that the ELA levels were decreased in the kidneys of DKD mice.Then,we found that ELA administration mitigated renal damage and downregulated the expression of fibronectin,collagenⅣ,and transforming growth factor-β1 in the db/db mice and the high glucose cultured HK-2 cells.Furthermore,the autophagy markers,Beclin-1 and LC3-Ⅱ/LC3-Ⅰratio,were significantly impaired in DKD,but the ELA treatment reversed these alterations.Mechanistically,the inhibitory effects of ELA on the secretion of fibrosis-associated proteins in high glucose conditions were blocked by pretreatment with 3-methyladenine(an autophagy inhibitor).In summary,these in vivo and in vitro results demonstrate that ELA effectively protects against DKD by activating high glucose-inhibited renal tubular autophagy,potentially serving as a novel therapeutic candidate for DKD.

Design and discovery of a highly potent ultralong-acting GLP-1 and glucagon co-agonist for attenuating renal fibrosis

The role of co-agonists of glucagon-like peptide-1 receptor(GLP-1R)and glucagon receptor(GCGR)in chronic kidney disease(CKD)remains unclear.Herein we found that GLP-1R and GCGR expression levels were lower in the kidneys of mice with CKD compared to healthy mice and were correlated with disease severity.Interestingly,GLP-1R or GCGR knockdown aggravated the progression of kidney injury in both diabetic db/db mice and non-diabetic mice undergoing unilateral ureteral obstruction(UUO).Based on the importance of GLP-1R and GCGR in CKD,we reported a novel monomeric peptide,1907-B,with dual-agonism on both GLP-1R and GCGR.The data confirmed that 1907-B had a longer half-life than long-acting semaglutide in rats or cynomolgus monkeys(~2-3 fold)and exhibited better therapeutic contribution to CKD than best-in-class monoagonists,semaglutide,or glucagon,in db/db mice and UUO mice.Various lock-of-function models,including selective pharmacological activation and genetic knockdown,confirmed that 1907-B’s effects on ameliorating diabetic nephropathy in db/db mice,as well as inhibiting kidney fibrosis in UUO mice,were mediated through GLP-1 and glucagon signaling.These findings highlight that 1907-B,a novel GLP-1R and GCGR co-agonist,exerts multifactorial improvement in kidney injuries and is an effective and promising therapeutic option for CKD treatment.

Correlation between the Expression of TGF-β1,Rhoa,SOX9 and Renal Interstitial Fibrosis in Rats with Chronic Kidney Disease

Objective:To study the correlation between the expression of transforming growth factor-β1(TGF-β1),Rho A,SOX9 and renal interstitial fibrosis in rats with chronic kidney disease.Methods:Forty specific pathogen-free(SPF)male SD rats were randomly divided into study group and control group,with 20 cases in each group.The study group was given adenine suspension by gavage,while the control group was given the same amount of saline by gavage.Blood,urine and renal tissue specimens were collected from all rats at 3rd and 6th weeks after modeling.The kidney weight,kidney weight/body weight,renal function indexes,the expression of TGF-β1,Rho A and SOX9 m RNA in renal tissues,Masson staining and renal interstitial fibrosis score were compared between the two groups.Pearson correlation was used to analyze the relationship between the renal interstitial fibrosis score and the expression of TGF-β1,Rho A and SOX9 m RNA in renal tissues of rats with chronic kidney disease.Results:The kidney weight and kidney weight/body weight of rats in the study group were higher than those in the control group at 3rd and 6th weeks after modeling(P<0.05).The quantitative levels of creatinine,urea nitrogen and 24-hour urinary protein in the study group were higher than those in the control group at 3rd and 6th weeks after modeling(P<0.05).The expression levels of TGF-β1,Rho A and SOX9 m RNA in renal tissues of rats in the study group were higher than those in the control group at 3rd and 6th weeks after modeling(P<0.05).The renal interstitial fibrosis score in the study group was higher than that in the control group at 3rd and 6th weeks after modeling(P<0.05).Pearson correlation analysis confirmed that the renal interstitial fibrosis score in rats with chronic kidney disease was positively correlated with the expression of TGF-β1,Rho A and SOX9 m RNA in renal tissues(P<0.05).Conclusion:The expression of TGF-β1,Rho A and SOX9 was abnormally high in rats with chronic kidney disease and was closely related to renal interstitial fibrosis,which may play a promoting role in the process of renal interstitial fibrosis.

The Hippo pathway and its correlation with acute kidney injury

Acute kidney injury(AKI) is a significant clinical complication with a substantial impact on morbidity and mortality, for which therapeutic options remain limited. The Hippo signaling pathway is an evolutionarily conserved pathway implicated in cell proliferation, dedifferentiation, and apoptosis via phosphorylation and inactivation of its downstream effectorsYes-associatedprotein(YAP)/transcriptional co-activator with PDZ-binding motif(TAZ). Recent studies have revealed that the Hippo pathway plays a pivotal role in the pathogenesis and repair of AKI. The Hippo pathway can mediate renal dysfunction through modulation of mitochondrial apoptosis under AKI conditions. Transient activation of YAP/TAZ in the acute phase of AKI may benefit renal recovery and regeneration, whereas persistent activation of YAP/TAZ in severe AKI may lead to maladaptive repair and transition to chronic kidney disease. This review aims to summarize recent findings on the associations between the Hippo pathway and AKI and to identify new therapeutic targets and strategies for AKI.

Apelin/APJ system and kidney disease

Apelin is an endogenous ligand of the apelin receptor(APJ),a seven-transmembrane G protein-coupled receptor.Apelin and APJ exist in a variety of tissues,with special status in the heart,lung and tumors.Furthermore,many research shows that the apelin/APJ system exerts a broad range of activities that affect kidney systems.This review we summarize the role of apelin/APJ system on renal fibrosis,renal ischemia/reperfusion injury and diabetic nephropathy,polycystic kidney disease,hemodialysis.It was found that the level expression of apelin m RNA in the inner stripe of kidney outer medulla was the highest,and the region is significantly correlated with water and sodium balance.In UUO mice model,intraperitoneal injection of Apelin can reduceα-SMA,the expression of TGF-1 and its receptor,and between renal stromal components also significantly decreased.These results show that Apelin can reduce the deposition of ECM and improve renal interstitial fibrosis.In renal ischemia/reperfusion injury studies show that apelin-13 can significantly reduce the damage induced by renal tubularlesions,renal cell death and the normal renal function is not completely lead to large damage.But in diabetic nephropathy,Apelin-APJ system can promote or slow DN disease progression is controversial,still needs further research.Analysis the receiver operating characteristic curve found that in the process of identifying ADPKD disease apelin and copeptin shows good receiver operating characteristic curve(ROC),cox proportional hazards regression model also showed apelin can predict on the progress of kidney disease.In hemodialysis patients the apelin levels and PTH levels were positively correlated,it could prompt apelin can protect bone dialysis patients.Apelin also can reduce Pit-1 inhibition of vascular smooth muscle cell osteoblast calcification and thus improve the aortic calcification,so Apelin may have a potential role in the treatment of vascular calcification in CKD.In kidney disease conditions,Apelin/APJ system plays a variety of biological functions,because of the Apelin protective on kidney,Apelin/APJ may be a potential material for the treatment of chronic kidney disease.

Histopathological characteristics and causes of kidney graft failure in the current era of immunosuppression

BACKGROUND The histopathological findings on the failing kidney allograft in the modern era is not well studied. In this study, we present our experience working with kidney transplant recipients with graft failure within one year of the biopsy.AIM To report the histopathological characteristics of failed kidney allografts in the current era of immunosuppression based on the time after transplant, cause of the end-stage renal disease and induction immunosuppressive medications.METHODS In a single-center observational study, we characterized the histopathological findings of allograft biopsies in kidney transplant recipients with graft failure within one year after the biopsy.RESULTS We identified 329 patients with graft failure that met the selection criteria between January 1, 2006 and December 31, 2016. The three most common biopsy findings were interstitial fibrosis and tubular atrophy(IFTA, 53%), acute rejection (AR, 43%) and transplant glomerulopathy(TG, 33%). Similarly, the three most common causes of graft failure based on the primary diagnosis were AR(40%),TG(17%), and IFTA(13%). Most grafts failed within two years of post-transplant(36%). Subsequently, approximately 10%-15% of grafts failed every two years: >2-4 years(16%), > 4-6 years(13%), > 6-8 years(11%), > 8-10 years(9%) and > 10 years(16%). AR was the most common cause of graft failure in the first six years(48%), whereas TG was the most prevalent cause of graft failure after 6 years(32%) of transplant.CONCLUSION In the current era of immunosuppression, AR is still the most common cause of early graft failure, while TG is the most prevalent cause of late graft failure.

Metallic ureteral stent in restoring kidney function: Nine case reports

BACKGROUND Retroperitoneal fibrosis is an exceptionally rare disease characterized by proliferation of fibrous tissue and inflammation in the retroperitoneum.It features many symptoms in the kidneys and in other organs and usually leads to ureteral obstruction.CASE SUMMARY Here we present 9 consecutive cases of idiopathic retroperitoneal fibrosis(IRPF)in patients who presented to the Department of Nephrology or Department of Rheumatology,Xuanwu Hospital,Capital Medical University,Beijing,China,between January 2012 and June 2017 with ureteral obstruction due to external compression of the ureter that led to hydronephrosis and kidney dysfunction.Computed tomography imaging was used to identify hydronephrosis and ureteral obstruction and to evaluate kidney function.Each patient was diagnosed with IRPF based on clinical observation and computed tomography examination results.To restore kidney function,a retrograde metallic stent was placed in the ureter under X-ray guidance 2 d after each patient’s admission.No perioperative complications occurred in any patient,but postoperative complications occurred in two patients as follows:Patient 2 had stent migration and repeated metallic stent infections that resolved with treatment;and patient 4 had postoperative hematuria because he resumed normal activities too soon after stent placement(contrary to instruction).Placement of the metallic ureteral stents provided relief from ureteral obstruction and restored kidney function in all patients.CONCLUSION Our 9-case series underscores the utility and efficacy of applying the Resonance®metallic ureteral stent to treat ureteral obstruction in patients with IRPF.For all retroperitoneal fibrosis cases in our series,ureteral stents provided effective relief and were shown to reduce the incidence rate of perioperative and postoperative complications.

Morphological and functional evaluation of chronic kidney disease using magnetic resonance imaging

X-ray computed tomography(CT),ultrasonography(US)and radionuclide scanning are important clinical methods for evaluating morphology of the kidney.These modalities are also applicable for estimating kidney function with time lapse analysis using proper contrastmedia as may be necessary.In the case of US,it can estimate kidney function based on the measurement of blood flow using the Doppler effect.Formerly,magnetic resonance imaging(MRI)was an inappropriate diagnostic imaging technique for abdominal organs because of their respiratory displacements.However,MRI is now actively used for kidney as well as liver or other parenchymal organs,in tandem with the technological advances.Unlike unenhanced X-ray CT,"conventional"MRI can distinguish the border between cortex and medulla in T1 or T2 weighted images.It was known that the border blurred with decreasing kidney function.Moreover,several other particular imaging methods were introduced in recent years,and these could be called"functional"MRI.In this review,the following are discussed:functional MRI for chronic kidney disease,which include blood oxygenation level-dependent MRI for evaluation of hypoxia,diffusion-weighted imagingfor evaluation of fibrosis,diffusion tensor imaging for evaluation of microstructure,and arterial spin labeling to evaluate the amount of organ perfusion,accompanied with several related articles.The ultimate goal of functional MRI is to provide useful in vivo information repeatedly for daily medical treatment non-invasively.

Shen Qi Wan attenuates renal interstitial fibrosis through upregulating AQP1

Renal interstitial fibrosis(RIF)is the crucial pathway in chronic kidney disease(CKD)leading to the end-stage renal failure.However,the underlying mechanism of Shen Qi Wan(SQW)on RIF is not fully understood.In the current study,we investigated the role of Aquaporin 1(AQP1)in SQW on tubular epithelial-to-mesenchymal transition(EMT).A RIF mouse model induced by adenine and a TGF-β1-stimulated HK-2 cell model were etablished to explore the involvement of AQP 1 in the protective effect of SQW on EMT in vitro and in vivo.Subsequently,the molecular mechanism of SQW on EMT was explored in HK-2 cells with AQP1 knockdown.The results indicated that SQW alleviated kidney injury and renal collagen deposition in the kidneys of mice induced by adenine,increased the protein expression of E-cadherin and AQP1 expression,and decreased the expression of vimentin andα-smooth muscle actin(α-SMA).Similarly,treatmement with SQW-containing serum significantly halted EMT process in TGF-β1 stimulated HK-2 cells.The expression of snail and slug was significantly upregulated in HK-2 cells after knockdown of AQP1.AQP1 knockdown also increased the mRNA expression of vimentin andα-SMA,and decreased the expression of E-cadherin.The protein expression of vimentin increased,while the expression of E-cadherin and CK-18 significantly decreased after AQP1 knockdown in HK-2 cells.These results revealed that AQP1 knockdown promoted EMT.Furthermore,AQP1 knockdown abolished the protective effect of SQW-containing serum on EMT in HK-2 cells.In sum,SQW attentuates EMT process in RIF through upregulation of the expression of AQP1.

The Theory of Homogeny of Liver and Kidney in the Treatment of Kidney and Liver Fibrosis

Chronic kidney disease （CKD） and chronic liver disease are both very harmful to human health almost all over the world, which lead to the fibrosis of the two organs ultimately. Currently, there are few satisfactory therapeutic methods in treating the two diseases. Some research works from Chinese medicine and Western medicine were done in the area recently, the results showed that kidney and liver fibrosis shared similar biological signals and events such as epithelial- mesenchymal transition （EMT） and transforming growth factor β 1, the same herbal medicine exhibited significantly improving effects on both liver fibrosis and kidney fibrosis by involving similar mechanism. This coincides with the theory of homogeny of Liver （Gan） and Kidney （Shen） of Chinese medicine. It would provides new clues in exploring the treatment of liver fibrosis and kidney fibrosis.