Anthrahydroquinone-2,6-disulfonate alleviates paraquat-induced kidney injury via the apelin-APJ pathway in rats

Objective:To explore the protective effects of anthrahydroquinone-2,6-disulfonate(AH_(2)QDS)on the kidneys of paraquat(PQ)poisoned rats via the apelin-APJ pathway.Methods:Male Sprague Dawley rats were divided into four experimental groups:control,PQ,PQ+sivelestat,and PQ+AH_(2)QDS.The PQ+sivelestat group served as the positive control group.The model of poisoning was established via intragastric treatment with a 20%PQ pesticide solution at 200 mg/kg.Two hours after poisoning,the PQ+sivelestat group was treated with sivelestat,while the PQ+AH_(2)QDS group was given AH_(2)QDS.Six rats were selected from each group on the first,third,and seventh days after poisoning and dissected after anesthesia.The PQ content of the kidneys was measured using the sodium disulfite method.Hematoxylin-eosin staining of renal tissues was performed to detect pathological changes.Apelin expression in the renal tissues was detected using immunofluorescence.Western blotting was used to detect the expression levels of the following proteins in the kidney tissues:IL-6,TNF-α,apelin-APJ(the apelin-angiotensin receptor),NF-κB p65,caspase-1,caspase-8,glucose-regulated protein 78(GRP78),and the C/EBP homologous protein(CHOP).In in vitro study,a PQ toxicity model was established using human tubular epithelial cells treated with standard PQ.Twenty-four hours after poisoning,sivelestat and AH_(2)QDS were administered.The levels of oxidative stress in human renal tubular epithelial cells were assessed using a reactive oxygen species fluorescence probe.Results:The PQ content in the kidney tissues of the PQ group was higher than that of the PQ+AH_(2)QDS group.Hematoxylin-eosin staining showed extensive hemorrhage and congestion in the renal parenchyma of the PQ group.Vacuolar degeneration of the renal tubule epithelial cells,deposition of crescent-like red staining material in renal follicles,infiltration by a few inflammatory cells,and a small number of cast formation were also observed.However,these pathological changes were less severe in the PQ+sivelestat group and the PQ+AH_(2)QDS group(P<0.05).On the third day after poisoning,immunofluorescence assay showed that the level of apelin in the renal tissues was significantly higher in the PQ+AH_(2)QDS group than in the PQ group.Western blotting analysis results showed that IL-6,TNF-α,NF-κB p65,caspase-1,caspase-8,GRP78,and CHOP protein levels in the PQ group were higher than in the PQ+AH_(2)QDS group(P<0.05).The expression of apelin-APJ proteins in the PQ+AH_(2)QDS group was higher than in the PQ+sivelestat and PQ groups(P<0.05);this difference was significant on Day 3 and Day 7.The level of oxidative stress in the renal tubular epithelial cells of the PQ+AH_(2)QDS group and the PQ+sivelestat group was significantly lower than in the PQ group(P<0.05).Conclusions:This study confirms that AH_(2)QDS has a protective effect on PQ-poisoned kidneys and its positive effect is superior to that of sivelestat.The mechanism of the protective effects of AH_(2)QDS may be linked to reduction in cellular oxidative stress,PQ content of renal tissue,inflammatory injury,endoplasmic reticulum stress,and apoptosis.AH_(2)QDS may play a role in the treatment of PQ poisoning by upregulating the expression of the apelin-APJ.

Optical coherence tomography of the living human kidney

Acute tubular necrosis(ATN)induced by ischemia is the most common insult to donor kidneysdestined for trarsplantation.ATN results from sweling and subsequent damage to cells lining thelkidney tubules.In this study,we demonstrate the capability of optical coherence tomography(OcT)to image the renal microst ructures of living human donor kidneys and potentially providea measure to det ermine the extent of A TN.We also found that Doppler-based OCT(i.e.,DOCT)reveals renal blood flow dynamics that is another major factor which could relate to post-transplant renal finction.All OCT/DoCT oberva tions were performed in a noninvasive,sterileand timely manner on intact human kidneys both prior to(er vivo)and following(in vivo)theirtransplantation.Our results indicate that this imaging model provides transplant surgeons withan objective visualization of the transplant lidneys prior and immediately post transplantation.

Focal Segmental Glomerulosclerosis in Côte d’Ivoire: Epidemiological, Clinical and Pathological Aspects

Focal segmental glomerulosclerosis (FSGS) is characterized histologically by hyalinosis and sclerosis of glomeruli associated or not with podocyte involvement. The objective of our work was to clarify the epidemiological aspects and histological variants of FSGS in C&#244;te d’Ivoire. Materials and Methods: This was a descriptive retrospective study, conducted from January 2015 to December 2019 using the renal biopsy registers (RB) of the Pathological Anatomy and Cytology departments of the Teaching Hospital of Cocody and Bouake in collaboration with the Nephrology Services of C&#244;te d'Ivoire and the sub-region. The biopsies underwent conventional histopathology and/or immunofluorescence techniques. The parameters analyzed were: frequency, age, gender, proteinuria, biopsy indications and histological aspects and the different correlations between histological aspects and socio-demographic characteristics. Results: FSGS represented 58.1% (n = 104) of glomerular nephropathies. The average age of patients was 32.1 ± 13.3 years, with extremes of 13 and 70 years. The sex ratio was equal to 1. Nephrotic syndrome (68.9%), chronic renal failure (14.3%) and acute renal failure (10.1%) were the main indications for renal biopsy (RB). The mean proteinuria at the time of diagnosis was 4 ± 3.7 g/24 h. It was massive (3.5 g/24 h) in 42.3% of patients. FSGS was primary in 29.8% (n = 31) and secondary in 70.2% (n = 73) of patients, of which 27.9% (n = 35) was due to HIV. According to the Columbia classification, 62.5% NOS type was found;23.1% collapsing type;7.7% tip lesion type;4.8% cell type and 1.9% perihilary type. Conclusion: FSGS is a complex heterogeneous entity. It affects young people in our context with a homogeneous gender distribution. Understanding its histogenesis is essential for optimal patient management.

Prenatal prednisone exposure disturbs fetal kidney development and its characteristics

Prednisone is a synthetic glucocorticoid that is commonly used in both human and veterinary medication.Now,it is also recognized as an emerging environmental contaminant.Pregnantwomenmay be exposed to prednisone actively or passively throughmultiple pathways and cause developmental toxicity to the fetus.However,the impact of prenatal prednisone exposure(PPE)on fetal kidney development remains unclear.In this study,pregnant mice were administered prednisone intragastrically during full-term pregnancy with different doses(0.25,0.5,or 1 mg/(kg·day)),or at the dose of 1 mg/(kg·day)in different gestational days(GD)(GD0-9,GD10-18,or GD0-18).The pregnant mice were euthanized on GD18.HE staining revealed fetal kidney dysplasia,with an enlarged glomerular Bowman’s capsule space and a reduced capillary network in the PPE groups.The expression of the podocyte and the mesangial cell marker genes was significantly reduced in the PPE groups.However,overall gene expression in renal tubules and collecting ducts were markedly increased.All of the above effects were more pronounced in high-dose,full-term pregnancy,and female fetuses.Studies on the mechanism of the female fetal kidney have revealed that PPE reduced the expression of Six2,increased the expression of Hnf1β,Hnf4α,and Wnt9b,and inhibited the expression of glial cell line-derived neurotrophic factor(GDNF)and Notch signaling pathways.In conclusion,this study demonstrated that there is a sex difference in the developmental toxicity of PPE to the fetal kidney,and the time effect is manifested as full-term pregnancy>early pregnancy>mid-late pregnancy.

Targeted delivery of celastrol to glomerular endothelium and podocytes for chronic kidney disease treatment

The etiology of chronic kidney disease(CKD)is complex and diverse,which could be briefly categorized to glomerular-or tubularoriginated.However,the final outcomes of CKD are mainly glomerular sclerosis,endothelial dysfunction and injury,and chronic inflammation.Thus,targeted delivery of drugs to the glomeruli in order to ameliorate glomerular endothelial damage may help alleviate CKD and help enrich our knowledge.The herb tripterygium wilfordii shows therapeutic effect on kidney disease,and celastrol(CLT)is one of its active ingredients but with strong toxicity.Therefore,based on the unique structure and pathological characteristics of the glomerulus,we designed a targeted delivery system named peptides coupled CLT-phospholipid lipid nanoparticles(PC-PLNs)to efficiently deliver CLT to damaged endothelial cells and podocytes in the glomerulus for CKD treatment and research.PC-PLNs could effectively inhibit inflammation,reduce endothelial damage,alleviate CKD severity,and reduce the toxicity of CLT.We also studied the mechanism of CLT in the treatment of nephropathy and found that CLT can increase the level of NO by increasing eNOS while inhibiting the expression of VCAM-1,thus provides an anti-inflammatory effect.Therefore,our study not only offered an efficient CKD drug formulation for further development,but also provided new medical knowledge about CKD.

Genetic variation of mannose-binding protein associated with glomerular immune deposition in IgA nephropathy

OBJECTIVE: To investigate the relationship between codon 54 gene polymorphism of the host defense molecule, mannose-binding protein (MBP), and the patterns of glomerular immune deposition in IgA nephropathy (IgAN). METHODS: IgAN patients with different patterns of glomerular immune deposition were selected and divided into two groups. Group A consisted of 77 patients with glomerular IgA and C3 deposits, and Group AGM consisted of 70 patients with glomerular IgA, IgG, IgM, C3 and Clq deposits. Clinical features and laboratory relevant data of all patients were collected. One-hundred and forty healthy adults were recruited as normal controls. The MBP gene codon 54 GGC/GAC polymorphism was investigated by using polymerase chain reaction and restriction fragment length polymorphism. RESULTS: The genotype frequency of GGC/GAC heterozygotes was significantly higher in Group AGM as compared with that of Group A (41.4% vs 19.5%, P

Glomerular chemokine expression and the effect of steroid and cyclophosphamide pulse therapy in human crescentic glomerulonephritis

OBJECTIVE: To study glomerular expression of C-C chemokines, monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1alpha and beta (MIP-1alpha, MIP-1beta) and the effect of steroid and cyclophosphamide (CTX) intermittent intravenous pulse therapy on expression in patients with crescentic glomerulonephritis (CGN) to further investigate the underlying mechanism of the treatment. METHODS: Twelve patients with initial biopsy-proven CGN(2), 6 with lupus nephritis (lupus-CGN, LN-CGN) and 6 with vasculitis, (vasculitis-CGN, V-CGN) were enrolled in this study. They underwent an initial biopsy before steroid and CTX intermittent intravenous pulse therapy and were biopsied again one to three months later. Expression of MCP-1, MIP-1alpha, MIP-1beta, and CD68 in glomeruli with cellular and fibrocellular crescents were examined by immunohistochemical analysis in serial sections of renal biopsies. The effect of the pulse therapy on histopathological changes was also observed. RESULTS: Although steroid and CTX intermittent intravenous pulse therapy markedly reduced the degree of glomerular crescent formation both in LN-CGN and V-CGN, the effect of the therapy on glomerular chemokine expression was significantly different between LN-CGN and V-CGN. It was found that steroid and CTX intermittent intravenous pulse therapy reduced the expression of CD68, MCP-1, and MIP-1alpha, but had no effect on MIP-1beta in glomeruli with cellular crescents of patients with LN-CGN. In patients with V-CGN, the therapy also reduced the expression of CD68, but had no effect on MCP-1, MIP-1alpha, and MIP-1beta in glomeruli with cellular crescents. It was noted that the degree of glomerulosclerosis and tubular interstitial fibrosis increased more significantly at the second biopsy in V-CGN as compared to LN-CGN. CONCLUSIONS: The efficacy of steroid and CTX intermittent intravenous pulse therapy in CGN might be affected by reduction of glomerular chemokine expression. The different changes in glomerular expression of MCP-1 and MIP-1alpha in patients with LN-CGN and V-CGN after pulse therapy may correlate to different responses to treatment and prognosis.

Establishment and functional characterization of the reversibly immortalized mouse glomerular podocytes(imPODs)

Glomerular podocytes are highly specialized epithelial cells and play an essential role in establishing the selective permeability of the glomerular filtration barrier of kidney.Maintaining the viability and structural integrity of podocytes is critical to the clinical management of glomerular diseases,which requires a thorough understanding of podocyte cell biology.As mature podocytes lose proliferative capacity,a conditionally SV40 mutant tsA58-immortalized mouse podocyte line(designated as tsPC)was established from the Immortomouse over 20 years ago.However,the utility of the tsPC cells is hampered by the practical inconvenience of culturing these cells.In this study,we establish a user-friendly and reversibly-immortalized mouse podocyte line(designated as imPOD),on the basis of the tsPC cells by stably expressing the wildtype SV40 T-antigen,which is flanked with FRT sites.We show the imPOD cells exhibit long-term high proliferative activity,which can be effectively reversed by FLP recombinase.The imPOD cells express most podocyte-related markers,including WT-1,Nephrin,Tubulin and Vinculin,but not differentiation marker Synaptopodin.The imPOD cells do not form tumor-like masses in vivo.We further demonstrate that TGFb1 induces a podocyte injury-like response in the FLP-reverted imPOD cells by suppressing the expression of slit diaphragm-associated proteins P-Cadherin and ZO-1 and upregulating the expression of mesenchymal markers,a-SMA,Vimentin and Nestin,as well as fibrogenic factors CTGF and Col1a1.Collectively,our results strongly demonstrate that the newly engineered im-POD cells should be a valuable tool to study podocyte biology both under normal and under pathological conditions.

胎儿肾小球毛细血管的发生及发育的扫描电镜观察

应用微血管铸型扫描电镜(SEM)观察了15例20～38周胎儿肾小球毛细血管发生及发育的形态学变化。结果显示:20～38周胎儿的肾脏内皮质肾小球生长发育较好,肾小球大小无明显变化,但其毛细血管形态显示了一定的差异。外皮质肾小球发育较差。在胎儿早期(5个月)较多初级肾小球的入球小动脉发出的毛细血管呈向前开放5～10支数量不等的小突起或弯曲成指状排列,部分肾动脉分支形成的终末血管(入球小动脉)呈光滑而又膨大的盲端或"结节"状。随着肾小球毛细血管发育,毛细血管袢数量增多,肾小球发育接近球形。近足月时处于初期发育的肾小球较少发现。肾小球的3种类型是由肾小球毛细血管早期发育所决定,其毛细血管来源于肾入球动脉形成的各级分支,以芽生形式形成。

胎儿肾小球血管构筑

应用微血管铸型扫描电镜观察１５例２０～３８周胎儿肾小球血管构筑。发现，球型肾小球占多数（７１．５％），菊花型（１６％）和混合型（１２．５％）较少，肾小球的类型是由胚胎早期发育所决定。入球与出球小动脉多为１支，少数有２支以上，在入、出球小动脉之间未观察到有直接吻合的血管，但少数肾小球与肾小球之间有毛细血管相交通，或肾小球与肾小球之间接触部分毛细血管形成直接吻合。此外，还观察到较少的近足月龄胎儿肾小球旁器内毛细血管的构筑，其毛细血管分布较局限，毛细血管直径大于其形成网眼的直径。

Epidemiology of biopsy-proven glomerular diseases in Chinese children: A scoping review

Background: Glomerular disease is the leading cause of chronic kidney disease globally. No scoping review reports have focused on China’’s spectrum of glomerular diseases in children. This study aimed to systematically identify and describe retrospective studies on pediatric glomerular disease based on available data on sex, age, study period, and region.Methods: Six databases were systematically searched for relevant studies from initiation to December 2021 in PubMed, Embase, Web of Science, Global Health Library, Wangfang Database, and CNKI.Results: Thirty-four studies were identified in the scoping review, including 40,430 patients with biopsy-proven diagnoses. The proportion of boys was significantly higher than that of girls. In this study, 28,280 (70%) cases were primary glomerular disease, 10,547 (26.1%) cases were diagnosed as secondary glomerular disease, and 1146 (2.8%) cases were hereditary glomerular disease. Minimal change disease is the most common glomerular disease among children in China, followed by mesangial proliferative glomerulonephritis, IgA nephropathy, and purpura nephritis. We observed increments in glomerular diseases in periods 2 (2001–2010) and 3 (2011–2021). The proportion of major glomerular diseases varies significantly in the different regions of China.Conclusion: The spectrum of pediatric glomerular diseases varied across sex, age groups, study periods, and regions, and has changed considerably over the past 30 years.