Role of resident memory T cells in neuroinflammatory and neurodegenerative diseases in the central nervous system

The immune system has been attracting increasing attention in the field of chronic neurological disorders in the central nervous system(CNS).Autoreactive T cells targeting CNS antigens play a crucial role in the development of various autoimmune diseases,such as multiple sclerosis(MS)and neuromyelitis optica spectrum disorder(NMOSD).Moreover,T cells are now recognized as a pivotal contributor to the pathology of neurodegenerative disorders,including Alzheimer's disease(AD),Parkinson's disease(PD),and multiple system atrophy.

Risk factors for developing osteoporosis in diabetic kidney disease and its correlation with calcium-phosphorus metabolism,FGF23,and Klotho

BACKGROUND The progression of diabetic kidney disease(DKD)affects the patient’s kidney glomeruli and tubules,whose normal functioning is essential for maintaining normal calcium(Ca)and phosphorus(P)metabolism in the body.The risk of developing osteoporosis(OP)in patients with DKD increases with the aggravation of the disease,including a higher risk of fractures,which not only affects the quality of life of patients but also increases the risk of death.AIM To analyze the risk factors for the development of OP in patients with DKD and their correlation with Ca-P metabolic indices,fibroblast growth factor 23(FGF23),and Klotho.METHODS One hundred and fifty-eight patients with DKD who were admitted into the Wuhu Second People’s Hospital from September 2019 to May 2021 were selected and divided into an OP group(n=103)and a normal bone mass group(n=55)according to their X-ray bone densitometry results.Baseline data and differences in Ca-P biochemical indices,FGF23,and Klotho were compared.The correlation of Ca-P metabolic indices with FGF23 and Klotho was discussed,and the related factors affecting OP in patients with DKD were examined by multivariate logistic regression analysis.RESULTS The OP group had a higher proportion of females,an older age,and a longer diabetes mellitus duration than the normal group(all P<0.05).Patients in the OP group exhibited significantly higher levels of intact parathyroid hormone(iPTH),blood P,Ca-P product(Ca×P),fractional excretion of phosphate(FeP),and FGF23,as well as lower estimated glomerular filtration rate,blood Ca,24-hour urinary phosphate excretion(24-hour UPE),and Klotho levels(all P<0.05).In the OP group,25-(OH)-D3,blood Ca,and 24-hour UPE were negatively correlated with FGF23 and positively correlated with Klotho.In contrast,iPTH,blood Ca,Ca×P,and FeP exhibited a positive correlation with FGF23 and an inverse association with Klotho(all P<0.05).Moreover,25-(OH)-D3,iPTH,blood Ca,FePO4,FGF23,Klotho,age,and female gender were key factors that affected the lumbar and left femoral neck bone mineral density.CONCLUSION The Ca-P metabolism metabolic indexes,FGF23,and Klotho in patients with DKD are closely related to the occurrence and development of OP.

Pathological mechanism of immune disorders in diabetic kidney disease and intervention strategies

Diabetic kidney disease is one of the most severe chronic microvascular complications of diabetes and a primary cause of end-stage renal disease.Clinical studies have shown that renal inflammation is a key factor determining kidney damage during diabetes.With the development of immunological technology,many studies have shown that diabetic nephropathy is an immune complex disease,and that most patients have immune dysfunction.However,the immune response associated with diabetic nephropathy and autoimmune kidney disease,or caused by ischemia or infection with acute renal injury,is different,and has a complicated pathological mechanism.In this review,we discuss the pathogenesis of diabetic nephropathy in immune disorders and the intervention mechanism,to provide guidance and advice for early intervention and treatment of diabetic nephropathy.

Evaluation of autoimmune phenomena in patients with nonalcoholic fatty liver disease on the basis of liver pathology

BACKGROUND Autoimmune phenomena can be used in some patients with nonalcoholic fatty liver disease(NAFLD)in the clinic,but these patients are not autoimmune hepatitis patients.AIM To determine whether autoimmunity is present in patients with NAFLD,this study was performed.METHODS A total of 104 patients with NAFLD diagnosed by liver biopsy at Tianjin Second People’s Hospital between 2019 and 2023 were enrolled.The patients were divided into three groups according to their biopsy results:The NAFL(n=36),nonalcoholic steatohepatitis(n=51),and liver cirrhosis groups(n=17).RESULTS The differences in IgA,an immune marker,among the three groups of patients were statistically significant(P=0.025).In all NAFLD patients,antinuclear antibody and anti-smooth muscle antibody were the most common autoantibodies.The antinuclear antibody detection rate was the highest at 48.1%.The cirrhosis group had the highest autoantibody positivity rate(64.7%).Portal enlargement is also common in NAFLD patients.The rates of positivity for portal lymphoplasmacytic infiltration,small bile duct hyperplasia and interfacial hepatitis were highest in the cirrhosis group;the differences between the cirrhosis group and the other two groups were significant(P<0.05).Hepatocellular rosettes were identified only in the cirrhosis group(11.8%).CONCLUSION Autoimmune phenomena occur in NAFLD patients,especially in patients with NAFLD-related cirrhosis,in whom this phenomenon may be more pronounced.

Exploring kidney biopsy findings in congenital heart diseases:Insights beyond cyanotic nephropathy

BACKGROUND The association between congenital heart disease and chronic kidney disease is well known.Various mechanisms of kidney damage associated with congenital heart disease have been established.The etiology of kidneydisease has commonly been considered to be secondary to focal segmental glomerulosclerosis(FSGS),however,this has only been demonstrated in case reports and not in observational or clinical trials.AIM To identify baseline and clinical characteristics,as well as the findings in kidney biopsies of patients with congenital heart disease in our hospital.METHODS This is a retrospective observational study conducted at the Nephrology Depart-ment of the National Institute of Cardiology“Ignacio Chávez”.All patients over 16 years old who underwent percutaneous kidney biopsy from January 2000 to January 2023 with congenital heart disease were included in the study.RESULTS Ten patients with congenital heart disease and kidney biopsy were found.The average age was 29.00 years±15.87 years with pre-biopsy proteinuria of 6193 mg/24 h±6165 mg/24 h.The most common congenital heart disease was Fallot’s tetralogy with 2 cases(20%)and ventricular septal defect with 2(20%)cases.Among the 10 cases,one case of IgA nephropathy and one case of membranoproliferative glomerulonephritis associated with immune complexes were found,receiving specific treatment after histopathological diagnosis,delaying the initiation of kidney replacement therapy.Among remaining 8 cases(80%),one case of FSGS with perihilar variety was found,while the other 7 cases were non-specific FSGS.CONCLUSION Determining the cause of chronic kidney disease can help in delaying the need for kidney replacement therapy.In 2 out of 10 patients in our study,interventions were performed,and initiation of kidney replacement therapy was delayed.Prospective studies are needed to determine the usefulness of kidney biopsy in patients with congenital heart disease.

Patterns of kidney diseases diagnosed by kidney biopsy and the impact of the COVID-19 pandemic in Yogyakarta,Indonesia:A single-center study

BACKGROUND Glomerular diseases rank third among the causes of chronic kidney disease worldwide and in Indonesia,and its burden continues to increase,especially regarding the sociodemographic index.Kidney biopsy remains the gold standard for the diagnosis and classification of glomerular diseases.It is crucial for developing treatment plans,determining the degree of histologic changes,and identifying disease relapse.AIM To describe the patterns of biopsy-proven kidney diseases in adult patients.METHODS We retrospectively reviewed the demographic,histopathologic,clinical,and laboratory data of 75 adult patients with biopsy-proven kidney diseases at our institution recorded from 2017 to 2022.RESULTS Among the patients,43(57.3%)were females,and the mean age was 31.52 years±11.70 years.The most common histopathologies were lupus nephritis(LN)(33.3%),minimal change disease(MCD)(26.7%),and focal segmental glomerulosclerosis(10.7%).LN(41.7%)was frequently diagnosed in women and MCD(28.1%)in men.The most common cause of nephritic syndrome was LN(36.7%)and of nephrotic syndrome was MCD(40%).CONCLUSION Different kidney disease patterns were observed in different sexes,age categories,clinical syndromes,and biopsy dates relative to the coronavirus disease 2019 pandemic.

Role of calcium in polycystic kidney disease:From signaling to pathology

Autosomal dominant polycystic kidney disease （ADPKD） is the most common inherited monogenic kidney disease. Characterized by the development and growth of cysts that cause progressive kidney enlargement, it ultimately leads to end-stage renal disease. Approximately 85% of ADPKD cases are caused by mutations in the PKD1 gene, while mutations in the PKD2 gene account for the remaining 15% of cases. The PKD1 gene encodes for polycystin-1 （PC1）, a large multi-functional memb-rane receptor protein able to regulate ion channel complexes, whereas polycystin-2 （PC2）, encoded by the PKD2 gene, is an integral membrane protein that functions as a calcium-permeable cation channel, located mainly in the endoplasmic reticulum （ER）. In the primary cilia of the epithelial cells, PC1 interacts with PC2 to form a polycystin complex that acts as a mechanosensor, regulating signaling pathways involved in the differentiation of kidney tubular epithelial cells. Despite progress in understanding the function of these proteins, the molecular mechanisms associated with the pathogenesis of ADPKD remain unclear. In this review we discuss how an imbalance between functional PC1 and PC2 proteins may disrupt calcium channel activities in the cilium, plasma membrane and ER, thereby altering intracellular calcium signaling and leading to the aberrant cell proliferation and apoptosis associated with the development and growth of renal cysts. Research in this feld could lead to the discovery of new molecules able to rebalance intracellular calcium, thereby normalizing cell proliferation and reducing kidney cyst progression.

Association of physical activity with risk of chronic kidney disease in China:A population-based cohort study

Background:Information on the association between physical activity(PA)and the risk of chronic kidney disease(CKD)is limited.We aimed to explore the associations of total,domain-specific,and intensity-specific PA with CKD and its subtypes in China.Methods:The study included 475,376 adults from the China Kadoorie Biobank aged 30-79 years during 2004-2008 at baseline.An interviewer-administered questionnaire was used to collect the information about PA,which was quantified as metabolic equivalent of task hours per day(MET-h/day)and categorized into 4 groups based on quartiles.Cox regression was used to analyze the association between PA and CKD risk.Results:During a median follow-up of 12.1 years,5415 incident CKD cases were documented,including 1159 incident diabetic kidney disease(DKD)cases and 362 incident hypertensive nephropathy(HTN)cases.Total PA was inversely associated with CKD risk,with an adjusted hazard ratio(HR,95%confidence interval(95%CI))of 0.83(0.75-0.92)for incident CKD in the highest quartile of total PA as compared with participants in the lowest quartile.Similar results were observed for risk of DKD and HTN,and the corresponding HRs(95%CIs)were 0.75(0.58-0.97)for DKD risk and 0.56(0.37-0.85)for HTN risk.Increased nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA were significantly associated with a decreased risk of CKD,with HRs(95%CIs)of 0.80(0.73-0.88),0.85(0.77-0.94),and 0.85(0.76-0.95)in the highest quartile,respectively.Conclusion:PA,including nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA,was inversely associated with the risk of CKD,including DKD,HTN,and other CKD,and such associations were dose dependent.

Incidental renal cell carcinoma post bilateral nephrectomy in autosomal dominant polycystic kidney disease

BACKGROUND Renal cell carcinoma(RCC)is more common in patients with autosomal dominant polycystic kidney disease(ADPKD)than in the general population.Diagnosing RCC in ADPKD is challenging due to the presence of multiple renal cysts,often leading to delays and difficulties in distinguishing RCC from cyst infection or hemorrhage.A total of 38 kidneys were excised from 19 patients,with a mean age of 56.8 years and an average hemodialysis duration of 84.2 months.Eight patients underwent open nephrectomies,and 11 underwent hand-assisted laparoscopic nephrec-tomies.RCC was detected in 15.8%of kidneys,affecting 21.1%of patients.Two patients had multifocal RCC in both kidneys.All RCC cases were pT1 stage,with the largest lesion averaging 16.5 mm in diameter.The average operative duration was 120 minutes,with intraoperative blood loss averaging 184.2 mL.Five patients required blood transfusions.Postoperative complications occurred in five patients,with a mean hospital stay of 17.1 days.The mean follow-up period was 28.1 months.CONCLUSION The prevalence of RCC is higher in patients with ADPKD with ESRD than in those with ESRD alone.Thus,clinicians should be cautious and implement surveillance programs to monitor the development of RCC in patients with ADPKD,particularly those on dialysis.

Application and management of continuous glucose monitoring in diabetic kidney disease

Diabetic kidney disease(DKD)is a common complication of diabetes mellitus that contributes to the risk of end-stage kidney disease(ESKD).Wide glycemic var-iations,such as hypoglycemia and hyperglycemia,are broadly found in diabetic patients with DKD and especially ESKD,as a result of impaired renal metabolism.It is essential to monitor glycemia for effective management of DKD.Hemoglobin A1c(HbA1c)has long been considered as the gold standard for monitoring glycemia for>3 months.However,assessment of HbA1c has some bias as it is susceptible to factors such as anemia and liver or kidney dysfunction.Continuous glucose monitoring(CGM)has provided new insights on glycemic assessment and management.CGM directly measures glucose level in interstitial fluid,reports real-time or retrospective glucose concentration,and provides multiple glycemic metrics.It avoids the pitfalls of HbA1c in some contexts,and may serve as a precise alternative to estimation of mean glucose and glycemic variability.Emerging studies have demonstrated the merits of CGM for precise monitoring,which allows fine-tuning of glycemic management in diabetic patients.Therefore,CGM technology has the potential for better glycemic monitoring in DKD patients.More research is needed to explore its application and management in different stages of DKD,including hemodialysis,peritoneal dialysis and kidney transplantation.

MicroRNA-630 alleviates inflammatory reactions in rats with diabetic kidney disease by targeting toll-like receptor 4

BACKGROUND Diabetic kidney disease(DKD)is a major complication of diabetes mellitus.Renal tubular epithelial cell(TEC)damage,which is strongly associated with the inflammatory response and mesenchymal trans-differentiation,plays a significant role in DKD;However,the precise molecular mechanism is unknown.The recently identified microRNA-630(miR-630)has been hypothesized to be closely associated with cell migration,apoptosis,and autophagy.However,the association between miR-630 and DKD and the underlying mechanism remain unknown.AIM To investigate how miR-630 affects TEC injury and the inflammatory response in DKD rats.METHODS Streptozotocin was administered to six-week-old male rats to create a hypergly cemic diabetic model.In the second week of modeling,the rats were divided into control,DKD,negative control of lentivirus,and miR-630 overexpression groups.After 8 wk,urine and blood samples were collected for the kidney injury assays,and renal tissues were removed for further molecular assays.The target gene for miR-630 was predicted using bioinformatics,and the association between miR-630 and toll-like receptor 4(TLR4)was confirmed using in vitro investigations and double luciferase reporter gene assays.Overexpression of miR-630 in DKD rats led to changes in body weight,renal weight index,basic blood parameters and histopathological changes.RESULTS The expression level of miR-630 was reduced in the kidney tissue of rats with DKD(P<0.05).The miR-630 and TLR4 expressions in rat renal TECs(NRK-52E)were measured using quantitative reverse transcription polymerase chain reaction.The mRNA expression level of miR-630 was significantly lower in the high-glucose(HG)and HG+mimic negative control(NC)groups than in the normal glucose(NG)group(P<0.05).In contrast,the mRNA expression level of TLR4 was significantly higher in these groups(P<0.05).However,miR-630 mRNA expression increased and TLR4 mRNA expression significantly decreased in the HG+miR-630 mimic group than in the HG+mimic NC group(P<0.05).Furthermore,the levels of tumor necrosis factor-alpha(TNF-α),interleukin-1β(IL-1β),and IL-6 were significantly higher in the HG and HG+mimic NC groups than in NG group(P<0.05).However,the levels of these cytokines were significantly lower in the HG+miR-630 mimic group than in the HG+mimic NC group(P<0.05).Notably,changes in protein expression were observed.The HG and HG+mimic NC groups showed a significant decrease in E-cadherin protein expression,whereas TLR4,α-smooth muscle actin(SMA),and collagen IV protein expression increased(P<0.05).Conversely,the HG+miR-630 mimic group exhibited a significant increase in E-cadherin protein expression and a notable decrease in TLR4,α-SMA,and collagen IV protein expression than in the HG+mimic NC group(P<0.05).The miR-630 targets TLR4 gene expression.In vivo experiments demonstrated that DKD rats treated with miR-630 agomir exhibited significantly higher miR-630 mRNA expression than DKD rats injected with agomir NC.Additionally,rats treated with miR-630 agomir showed significant reductions in urinary albumin,blood glucose,TLR4,and proinflammatory markers(TNF-α,IL-1β,and IL-6)expression levels(P<0.05).Moreover,these rats exhibited fewer kidney lesions and reduced infiltration of inflammatory cells.CONCLUSION MiR-630 may inhibit the inflammatory reaction of DKD by targeting TLR4,and has a protective effect on DKD.

Urinary exosomal microRNA-145-5p and microRNA-27a-3p act as noninvasive diagnostic biomarkers for diabetic kidney disease

BACKGROUND Diabetic kidney disease(DKD),characterized by increased urinary microalbumin levels and decreased renal function,is the primary cause of end-stage renal di-sease.Its pathological mechanisms are complicated and multifactorial;Therefore,sensitive and specific biomarkers are needed.Urinary exosome originate from diverse renal cells in nephron segments and partially mirror the pathological changes in the kidney.The microRNAs(miRNAs)in urinary exosome are remark-ably stable and highly tissue-specific for the kidney.METHODS Type 2 diabetic mellitus(T2DM)patients were recruited from the Second Hospital of Hebei Medical University and were divided into two groups:DM,diabetic pa-tients without albuminuria[urinary albumin to creatinine ratio(UACR)<30 mg/g]and DKD,diabetic patients with albuminuria(UACR≥30 mg/g).Healthy subjects were the normal control(NC)group.Urinary exosomal miR-145-5p,miR-27a-3p,and miR-29c-3p,were detected using real-time quantitative polymerase chain reaction.The correlation between exosomal miRNAs and the clinical in-dexes was evaluated.The diagnostic values of exosomal miR-145-5p and miR-27a-3p in DKD were determined using receiver operating characteristic(ROC)analysis.Biological functions of miR-145-5p were investigated by performing RESULTS Urinary exosomal expression of miR-145-5p and miR-27a-3p was more upregulated in the DKD group than in the DM group(miR-145-5p:4.54±1.45 vs 1.95±0.93,P<0.001;miR-27a-3p:2.33±0.79 vs 1.71±0.76,P<0.05)and the NC group(miR-145-5p:4.54±1.45 vs 1.55±0.83,P<0.001;miR-27a-3p:2.33±0.79 vs 1.10±0.51,P<0.001).The exosomal miR-145-5p and miR-27a-3p positively correlated with albuminuria and serum creatinine and negatively correlated with the estimated glomerular filtration rate.miR-27a-3p was also closely related to blood glucose,gly-cosylated hemoglobin A1c,and low-density lipoprotein cholesterol.ROC analysis revealed that miR-145-5p had a better area under the curve of 0.88[95%confidence interval(CI):0.784-0.985,P<0.0001]in diagnosing DKD than miR-27a-3p with 0.71(95%CI:0.547-0.871,P=0.0239).Bioinformatics analysis revealed that the target genes of miR-145-5p were located in the actin filament,cytoskeleton,and extracellular exosome and were involved in the pathological processes of DKD,including apoptosis,inflammation,and fibrosis.CONCLUSION Urinary exosomal miR-145-5p and miR-27a-3p may serve as novel noninvasive diagnostic biomarkers or promising therapeutic targets for DKD.

Meta-analysis of the association between chronic periodontitis and chronic kidney disease

BACKGROUND Many scholars have performed several clinical studies have investigated the association between chronic periodontitis(CP)and chronic kidney disease(CKD).However,there are still differences between these research results,and there is no unified conclusion.Therefore,a systematic review is required to understand this issue fully.AIM To explore the correlation between CP and CKD.METHODS Literature on the correlation between CP and CKD,as well as the clinical attachment level(CAL)and pocket probing depth(PPD)of CKD and non-CKD,were retrieved from PubMed,Embase,the Cochrane Library,and Web of Science repositories until January 2024.After the effective data were extracted,data processing and statistics were performed using Stata 12.0.RESULTS Of the 22 studies,13 were related to CP and CKD,and 9 reported CAL and PPD in patients with CKD and healthy controls.Meta-analysis of the correlation between CP and CKD revealed that CKD probability in people with CP was 1.54 times that of healthy individuals[relative risk=1.54,95%confidence interval(CI):1.40-1.70],and CP incidence in patients with CKD was 1.98 times that of healthy individuals[overall risk(OR)=1.98,95%CI:1.53-2.57].Meta-analysis of CAL and PPD evaluations between CKD patients and healthy individuals showed that CAL and PPD levels were higher in CKD patients[standard mean difference(SMD)of CAL=0.65,95%CI:0.29-1.01;SMD of PPD=0.33,95%CI:0.02-0.63].CONCLUSION A bidirectional association exists between CP and CKD.CKD risk is increased in CP patients and vice versa.Periodontal tissue or tooth loss risks increase over time in CKD patients.

Risk factors for cognitive impairment in patients with chronic kidney disease

BACKGROUND Chronic kidney disease(CKD)patients have been found to be at risk of concurrent cognitive dysfunction in previous studies,which has now become an important public health issue of widespread concern.AIM To investigate the risk factors for concurrent cognitive dysfunction in patients with CKD.METHODS This is a prospective cohort study conducted among patients with CKD between October 2021 and March 2023.A questionnaire was formulated by literature review and expert consultation and included questions about age,sex,education level,per capita monthly household income,marital status,living condition,payment method,and hypertension.RESULTS Logistic regression analysis showed that patients aged 60-79 years[odds ratio(OR)=1.561,P=0.015]and≥80 years(OR=1.760,P=0.013),participants with middle to high school education(OR=0.820,P=0.027),divorced or widowed individuals(OR=1.37,P=0.032),self-funded patients(OR=2.368,P=0.008),and patients with hypertension(OR=2.011,P=0.041)had a higher risk of cognitive impairment.The risk of cognitive impairment was lower for those with a college degree(OR=0.435,P=0.034)and married individuals.CONCLUSION The risk factors affecting cognitive dysfunction are age,60-79 years and≥80 years;education,primary school education or less;marital status,divorced or widowed;payment method,selffunded;hypertension;and CKD.

Correlation of MRI-determined small bowel Crohn’s disease categories with medical response and surgical pathology

AIM: To determine whether magnetic resonance imaging (MRI) can be used to categorize small bowel Crohn's disease (SB CD) into groups that correlate with response to medical therapy and surgical pathology.METHODS: Data was collected from all patients with MRI evidence of SB CD without significant colonic disease over a 32-mo period. Two radiologists, blinded to clinical findings, evaluated each MRI and grouped them based on bowel wall thickness and wall enhancement. These categories were: (1) "fibrosis", (2) "mild segmental hyper-enhancement and mild wall thickening", (3) "mild segmental hyper-enhancement and marked wall thickening", (4) "marked segmental transmural hyper-enhancement". Patient response to additional medical therapy post-MRI was prospectively determined at 8-wk. Non-responders underwent endoscopy and were offered therapeutic endoscopy or surgery. Surgical pathology was assessed against the MRI category. RESULTS: Fifty-five patients were included. Females and category "2" patients were more likely, and patients with luminal narrowing and hold-up less likely, to respond to medical therapy (P < 0.05). Seventeen patients underwent surgery. The surgical pathologicalfindings of fibrosis and the severity of inflammation correlated with the MRI category in all cases.CONCLUSION: Our fi ndings suggest that SB CD can be grouped by the MRI f indings and that these groups are associated with patients more likely to respond to continued medical therapy. The MRI categories also correlated with the presence and level of intestinal inflammation and fibrosis on surgical pathology, and may be of prognostic use in the management of CD patients.

Kidneys in chronic liver diseases

Acute kidney injury(AKI),defined as an abrupt increase in the serum creatinine level by at least 0.3 mg/dL,occurs in about 20% of patients hospitalized for decompensating liver cirrhosis.Patients with cirrhosis are susceptible to developing AKI because of the progressive vasodilatory state,reduced effective blood volume and stimulation of vasoconstrictor hormones.The most common causes of AKI in cirrhosis are pre-renal azotemia,hepatorenal syndrome and acute tubular necrosis.Differential diagnosis is based on analysis of circumstances of AKI development,natriuresis,urine osmolality,response to withdrawal of diuretics and volume repletion,and rarely on renal biopsy.Chronic glomerulonephritis and obstructive uropathy are rare causes of azotemia in cirrhotic patients.AKI is one of the last events in the natural history of chronic liver disease,therefore,such patients should have an expedited referral for liver transplantation.Hepatorenal syndrome(HRS) is initiated by progressive portal hypertension,and may be prematurely triggered by bacterial infections,nonbacterial systemic inflammatory reactions,excessive diuresis,gastrointestinal hemorrhage,diarrhea or nephrotoxic agents.Each type of renal disease has a specific treatment approach ranging from repletion of the vascular system to renal replacement therapy.The treatment of choice in type 1 hepatorenal syndrome is a combination of vasoconstrictor with albumin infusion,which is effective in about 50% of patients.The second-line treatment of HRS involves a transjugular intrahepatic portosystemic shunt,renal vasoprotection or systems of artificial liver support.

Gut microbiota and diabetic kidney diseases: Pathogenesis and therapeutic perspectives

Diabetic kidney disease(DKD)is one of the major chronic complications of diabetes mellitus(DM),as well as a main cause of end-stage renal disease.Over the last few years,substantial research studies have revealed a contributory role of gut microbiota in the process of DM and DKD.Metabolites of gut microbiota like lipopolysaccharide,short-chain fatty acids,and trimethylamine N-oxide are key mediators of microbial–host crosstalk.However,the underlying mechanisms of how gut microbiota influences the onset and progression of DKD are relatively unknown.Besides,strategies to remodel the composition of gut microbiota or to reduce the metabolites of microbiota have been found recently,representing a new potential remedial target for DKD.In this minireview,we will address the possible contribution of the gut microbiota in the pathogenesis of DKD and its role as a therapeutic target.

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.

Roles and regulation of bone morphogenetic protein-7 in kidney development and diseases

The gene encoding bone morphogenetic protein-7(BMP7) is expressed in the developing kidney in embryos and also in the mature organ in adults. During kidney development, expression of BMP7 is essential to determine the final number of nephrons in and proper size of the organ. The secreted BMP7 acts on the nephron progenitor cells to exert its dual functions: To maintain and expand the progenitor population and to provide them with competence to respond to differentiation cues, each relying on distinct signaling pathways. Intriguingly, in the adult organ, BMP7 has been implicated in protection against and regeneration from injury. Exogenous administration of recombinant BMP7 to animal models of kidney diseases has shown promising effects in counteracting inflammation, apoptosis and fibrosis evoked upon injury. Although the expression pattern of BMP7 has been well described, the mechanisms by which it is regulated have remained elusive and the processes by which the secretion sites of BMP7 impinge upon its functions in kidney development and diseases have not yet been assessed. Understanding the regulatory mechanisms will pave the way towards gaining better insight into the roles of BMP7, and to achieving desired control of the gene expression as a therapeutic strategy for kidney diseases.

Experimental models for preclinical research in kidney disease

Acute kidney injury(AKI)and chronic kidney disease(CKD)are significant public health issues associated with a long-term increase in mortality risk,resulting from various etiologies including renal ischemia,sepsis,drug toxicity,and diabetes mellitus.Numerous preclinical models have been developed to deepen our understanding of the pathophysiological mechanisms and therapeutic approaches for kidney diseases.Among these,rodent models have proven to be powerful tools in the discovery of novel therapeutics,while the development of kidney organoids has emerged as a promising advancement in the field.This review provides a comprehensive analysis of the construction methodologies,underlying biological mechanisms,and recent therapeutic developments across different AKI and CKD models.Additionally,this review summarizes the advantages,limitations,and challenges inherent in these preclinical models,thereby contributing robust evidence to support the development of effective therapeutic strategies.