Induced pluripotent stem cell (iPSC) lines for studies investigating many diseases can be established from peripheral blood mononuclear cells; here, an iPSC line was established from CD34+ cells isolated from the peripheral blood of a healthy woman. The cells were electrotransfected with three different recombinant plasmids to generate a normal-karyotype iPSC line that expresses characteristic surface markers and other pluripotent stem cell genes and can differentiate into all three germ layers in vivo. These newly established iPSC lines, a normal human cell line, can serve as a control line in studies investigating the pathogenesis of various diseases and meet the conditions for organoid studies.

High-affinity Na(+)-dependent dicarboxylate cotransporter (NaDC3) can transport Krebs cycle intermediates into cells. Our previous study has shown that NaDC3 promotes cellular senescence, but its mechanism is not clear. It is known that when the concentration of intermediates in Krebs cycle is increased, NAD(+)/NADH ratio will be decreased. NAD(+)-dependent histone deacetylase sirtuin1 (SIRT1) prolongs mammalian cellular lifespan. Therefore, we propose that NaDC3 accelerates cellular aging by inhibiting SIRT1. After NaDC3 was overexpressed in two human embryo lung fibroblastic cell lines, WI38 and MRC-5, we found that the cells displayed aging-related phenotypes in advance. Meanwhile, the level of SIRT1 activity was down-regulated. In WI38/hNaDC3 cells treated with the activators of SIRT1, aging-related phenotypes induced by NaDC3 were obviously improved. The NAD(+)/NADH ratio in WI38/hNaDC3 cells was also decreased. Further study found that enhanced intracellular NAD(+) level could attenuate the aging phenotypes induced by NaDC3. Thus, NaDC3 promotes cellular senescence probably by inhibiting NAD(+)-dependent SIRT1.

The pathogenic mechanism of autosomal dominant polycystic kidney disease (ADPKD) is unclear. Similar to tumour cells, polycystic kidney cells are primarily dependent on aerobic glycolysis for ATP production. Compared with rodents, miniature pigs are more similar to humans. This study is the first time to investigate the effects of the combination of metformin and 2-deoxyglucose (2DG) in a pig model of chronic progressive ADPKD.

Nerol (C10H18O), an acyclic monoterpene, naturally presents in plant essential oils, and is used widely in food, cosmetics and pharmaceuticals as the valuable fragrance. Meanwhile, chemical synthesis is the only strategy for large-scale production of nerol, and the disadvantages of chemical synthesis greatly limit the production and its application. These defects drive the interests of researchers shift to the production of nerol by eco-friendly methods known as biosynthesis methods. However, the main technical bottleneck restricting the biosynthesis of nerol is the lacking of corresponding natural aroma-producing microorganisms.

Gentamicin may cause acute kidney injury. The pathogenesis of gentamicin nephrotoxicity is unclear. Autophagy is a highly conserved physiological process involved in removing damaged or aged biological macromolecules and organelles from the cytoplasm. The role of autophagy in the pathogenesis of gentamicin nephrotoxicity is unclear. The miniature pigs are more similar to humans than are those of rodents, and thus they are more suitable as human disease models. Here we established the first gentamicin nephrotoxicity model in miniature pigs, investigated the role of autophagy in gentamicin-induced acute kidney injury, and determined the prevention potential of rapamycin against gentamicin-induced oxidative stress and renal dysfunction. At 0, 1, 3, 5, 7 and 10 days after gentamicin administration, changes in autophagy, oxidative damage, apoptosis and inflammation were assessed in the model group. Compared to the 0-day group, gentamicin administration caused marked nephrotoxicity in the 10-day group. In the kidneys of the 10-day group, the level of autophagy decreased, and oxidative damage and apoptosis were aggravated. After rapamycin intervention, autophagy activity was activated, renal damage in proximal tubules was markedly alleviated, and interstitium infiltration of inflammatory cells was decreased. These results suggest that rapamycin may ameliorate gentamicin-induced nephrotoxicity by enhancing autophagy.

Background. MicroRNAs (miRNAs) have been found in virtually all body fluids and used successfully as biomarkers for various diseases. Evidence indicates that miRNAs have important roles in IgA nephropathy (IgAN), a major cause of renal failure. In this study, we looked for differentially expressed miRNAs in IgAN and further evaluated the correlations between candidate miRNAs and the severity of IgAN. Methods. Microarray and RT-qRCR (real-time quantitative polymerase chain reaction) were sequentially used to screen and further verify miRNA expression profiles in urinary sediments of IgAN patients in two independent cohorts. The screening cohort consisted of 32 urine samples from 18 patients with IgAN, 4 patients with MN (membranous nephropathy), 4 patients with MCD (minimal changes disease) and 6 healthy subjects; the validation cohort consisted of 102 IgAN patients, 41 MN patients, 27 MCD patients and 34 healthy subjects. The renal pathological lesions of patients with IgAN were evaluated according to Lee's grading system and Oxford classification. Results. At the screening phase, significance analysis of microarrays analysis showed that no miRNA was differentially expressed in the IgAN group compared to all control groups. But IgAN grade I-II and III subgroups (according to Lee's grading system) shared dysregulation of two miRNAs (miR-3613-3p and miR-4668-5p). At the validation phase, RT-qPCR results showed that urinary level of miR-3613-3p was significantly lower in IgAN than that in MN, MCD and healthy controls (0.47, 0.44 and 0.24 folds, respectively, all P < 0.01 by Mann-Whitney U test); urinary level of miR-4668-5p was also significantly lower in IgAN than that in healthy controls (0.49 fold, P < 0.01). Significant correlations were found between urinary levels of miR-3613-3p with 24-hour urinary protein excretion (Spearman r = 0.50, P = 0.034), eGFR (estimated glomerular filtration rate) (r = - 0.48, P = 0.043) and Lee's grades (r = 0.57, P = 0.014). Similarly, miR-4668-5p was significantly correlated with eGFR (r = - 0.50, P = 0.034) and Lee's grades (r = 0.57, P = 0.013). For segmental glomerulosclerosis according to Oxford classification, patients scored as S0 had significantly lower levels of urinary miR-3613-3p and miR-4668-5p than those scored as S1 (0.41 and 0.43 folds, respectively, all P < 0.05). Conclusions. The expression profile of miRNAs was significantly altered in urinary sediments from patients with IgAN. Urinary expression of miR-3613-3p was down-regulated in patients with IgAN. Moreover, urinary levels of both miR-3613-3p and miR-4668-5p were correlated with disease severity. Further studies are needed to explore the roles of miR-3613-3p and miR-4668-5p in the pathogenesis and progression of IgA nephropathy.

The main pathological characteristic of glomerulonephritis is diffuse mesangial cell proliferation. MiR-34a is associated with the proliferation of various organs and cancer cells. However, the role of miR-34a in renal proliferation diseases is not clear. Therefore, this study aimed to elucidate the mechanism of miR-34a in the regulation of renal mesangial cell proliferation. The miR-34a expression level at different time points in an anti-Thy1 mesangial proliferative nephritis rat model was determined by qRT-PCR. The cell proliferation rate and cell cycle changes were measured in the in vitro cultured rat mesangial cells (RMCs). Our results suggested that miR-34a expression was negatively correlated with the degree of cell proliferation in the anti-Thy1 nephritis model. MiR-34a could extend the G0/G1 phase and block cell proliferation in RMCs. Dual-luciferase assay results showed that there were binding sites of miR-34a at 3'-UTR of platelet-derived growth factor receptor-β (PDGFR-β). MiR-34a can inhibit PDGFR-β protein expression at a post-transcriptional level, suppress Ras/MAPK signaling pathways, and down-regulate expression of cell cycle proteins at the G0/G1 phase, such as cyclin D1, CDK4/CDK6. In addition, miR-34a may also inhibit RMC proliferation by directly targeting cyclin E and CDK2. MiR-34a inhibits exogenous stimuli-induced proliferation of mesangial cells. Expression levels of phospho-PDGFR-β and phospho-MEK1 (an important downstream molecule in PDGFR-β-induced signaling pathway) were significantly increased in the anti-Thy-1 nephritis rat model. These results suggest that miR-34a may regulate RMC proliferation by directly inhibiting expressions of PDGFR-β, MEK1, and cell cycle proteins, cyclin E and CDK2.

Numerous studies have demonstrated the life-extending effect of caloric restriction. It is generally accepted that caloric restriction has health benefits, such as prolonging lifespan and delaying the onset and progression of CKD in various species, especially in rodent models. Although many studies have tested the efficacy of caloric restriction, no complete quantitative analysis of the potential beneficial effects of reducing caloric intake on the development and progression of CKD has been published.

The mechanisms of kidney aging are not yet clear. Studies have shown that immunological inflammation is related to kidney aging. Toll-like receptors (TLRs) are one of the receptor types of the body's innate immune system. The function of the TLR system and the mechanisms by which it functions in renal aging remain unclear. In the present study, we, for the first time, systematically investigated the role of the TLR system and the inflammation responses activated by TLRs during kidney aging.

Polycystic kidney disease (PKD) caused by PKD2 mutation is an important type of autosomal dominant PKD. In this study, peripheral blood mononuclear cells from a patient with PKD2 polycystic kidney disease were reprogrammed to obtain induced pluripotent stem cells (iPSCs). After stable amplification, the pluripotency of the iPSCs was determined by identifying their cell-surface markers, their expression of pluripotency-related genes, and their ability to form teratomas with three germ layers in vivo. The establishment of the iPSC line could provide a basis for a kidney-like organ model of human PKD caused by PKD2 mutation for use in studying the pathogenesis of PKD along with relevant screening and testing intervention drugs.

Polycystic kidney disease (PKD) is a common hereditary kidney disease with abnormal proliferation and apoptosis of kidney cystic epithelial cells, eventually leading to chronic renal failure. Currently, there are no effective treatment methods. Similar to tumor cells, cystic epithelial cells have abnormal glycolysis and over-activation of proliferation signaling pathways. In the present study, for the first time, we investigated the effects of low-dose combinational use of 2-deoxyglucose (2-DG) and metformin (MET) on the proliferation and apoptosis in the human cystic kidney epithelial cells. Cystic epithelia cells were divided into control group, 2-DG group, MET group and 2-DG+MET group. Cell Proliferation, apoptosis and glucose metabolism were measured in each group. The results showed that low-dose combinational treatment of 2-DG and MET significantly inhibited the proliferation of renal cystic epithelial cells by suppressing the activities of PKA, mTOR and ERK signaling pathways and upregulating PI3K/Akt pathway. Combination of both drugs increased the apoptosis rates of cystic epithelial cells. Two drugs inhibited glucose metabolic phenotypes, glycolysis and oxidative phosphorylation, and significantly lowered the intracellular ATP level in cystic epithelial cells. 2-DG could also neutralize excessive production of lactate (lactic acidosis) caused by MET and both drugs had complementary effect for cystic epithelial cells. These results reveal that combinational use of low-dose 2-DG and MET can markedly inhibit proliferation via modulating glucose metabolic phenotypes in human polycystic kidney epithelial cells, low-dose combinational use of both drugs can also lower the toxic effects of each drug, and is a novel strategy for future treatment of human polycystic kidney disease.

This study aimed to evaluate the value of urinary angiostatin levels for assessing disease severity and progression of IgA nephropathy (IgAN).

Renal aging is always accompanied by increased oxidative stress. Hydrogen sulfide (H2S) can be up-regulated by 50% dietary restriction (DR) for 7-day and can block mitochondrial oxidative stress. H2S production exerts a critical role in yeast, worm, and fruit fly models of DR-mediated longevity. In this study, we found that renal aging could be attenuated by 30% DR for 6-month (DR-6M) and life-long (DR-LL), but not for 6-week (DR-6W). The expressions of cystathionine-γ-lyase (CGL) and cystathionine-β- synthase (CBS) were improved by DR-6M and DR-LL. Endogenous H2S production shared the same trend with CBS and CGL, while glutathione (GSH) didn't. When comparing efficiencies of DR for different durations, more evident production of H2S was found in DR-6M and DR-LL than in DR-6W. Finally the level of oxidative stress was improved by DR-6M and DR-LL rather than by DR-6W. It concluded that aged rats had the ability to produce enough H2S on 30% DR interventions protecting against renal aging, and the effect of DR for long-term were more significant than that of DR for short-term.

The mechanisms of diabetic renal injury remain unclear. Recent studies have shown that immunological and inflammatory elements play important roles in the initiation and development of diabetic nephropathy (DN). Toll-like receptors (TLRs) comprise a superfamily of innate immune system receptors. The roles and mechanisms of TLRs in the pathogenesis of diabetic renal lesions are mostly unknown. Compared with rodents, miniature pigs are more similar to humans with respect to metabolism, kidney structure, and immune system, and therefore represent an ideal large-animal model for DN mechanistic studies. A diabetes model was established by feeding miniature pigs with high-sugar and high-fat diets. Functional and pathological markers, expression and activation of endogenous TLR ligands [HSP70 (heat shock protein 70) and HMGB1], TLR1 to TLR11 and their downstream signaling pathway molecules (MyD88, IRAK-1, and IRF-3), nuclear factor κB (NF-κB) signaling pathway molecules (IKKβ, IκBα, and NF-κBp65), inflammatory cytokines [IL-6 (interleukin-6), MIP-2, MCP-1, CCL5, and VCAM-1 (vascular cell adhesion molecule-1)], and infiltration of inflammatory cells were systematically evaluated. The expression of HSP70 was significantly increased in diabetic pig kidneys. The expression of MyD88-dependent TLR2, TLR4, TLR5, TLR7, TLR8, and TLR11 and their downstream signaling molecules MyD88 and phospho-IRAK-1 (activated IRAK-1), as well as that of MyD88-independent TLR3 and TLR4 and their downstream signaling molecule phospho-IRF-3 (activated IRF-3), was significantly up-regulated. The expression and activation of NF-κB pathway molecules phospho-IKKβ, phospho-IκBα, NF-κBp65, and phospho-NF-κBp65 were significantly increased. Levels of IL-6, MIP-2, MCP-1, CCL5, VCAM-1, and macrophage marker CD68 were significantly increased in diabetic pig kidneys. These results suggested that the metabolic inflammation activated by TLRs might play an important role in diabetic renal injuries.

The pathogenic mechanism of polycystic kidney disease (PKD) is unclear. Abnormal glucose metabolism is maybe involved in hyper-proliferation of renal cyst epithelial cells. Mini-pigs are more similar to humans than rodents and therefore, are an ideal large animal model. In this study, for the first time, we systematically investigated the changes in glucose metabolism and cell proliferation signaling pathways in the kidney tissues of chronic progressive PKD mini-pig models created by knock-outing PKD1gene. The results showed that in the kidneys of PKD mini-pigs, the glycolysis is increased and the expressions of key oxidative phosphorylation enzymes Complexes I and IV significantly decreased. The activities of mitochondrial respiration chain Complexes I and IV significantly decreased; the phosphorylation level of key metabolism-modulating molecule AMP-activated protein kinase (AMPK) significantly decreased; and the mammalian target of rapamycin (mTOR) and extracellular signal-regulated kinase (ERK) signaling pathway are activated obviously. This study showed that in the kidneys of PKD mini-pigs, the level of glycolysis significantly increased, oxidative phosphorylation significantly decreased, and cell proliferation signaling pathways significantly activated, suggesting that metabolic changes in PKD may result in the occurrence and development of PKD through the activation of proliferation signaling pathways.

For IgA nephropathy (IgAN), tubular atrophy/interstitial fibrosis is the most important prognostic pathological indicator in the mesangial and endocapillary hypercellularity, segmental sclerosis, interstitial fibrosis/tubular atrophy, and presence of crescents (MEST-C) score. The identification of non-invasive biomarkers for tubular atrophy/interstitial fibrosis would aid clinical monitoring of IgAN progression and improve patient prognosis.

Staphylococcal infection has become a common cause of postinfectious glomerulonephritis in the past 3 decades. Because few investigations focus on this disease, the demographics and clinicopathological features of glomerulonephritis related to staphylococcal infection are not well characterized. We conducted a pooled analysis of published literature in electronic databases and analyzed the clinical features, laboratory findings, and histopathological changes. The patients were divided into 4 groups based on their prognosis: remission, persistent renal dysfunction, end-stage renal disease (ESRD), or death. A logistic regression model was used to identify the determinants of disease outcome. A total of 83 (64 men) patients with glomerulonephritis related to staphylococcal infection from 31 reports were analyzed. The mean age was 58 years (58 ± 17). Majority of the reports originated from Taiwan, Japan, and the United States. Clinical characteristics of the cases were hematuria (82/83), proteinuria (78/83), and acute kidney injury (75/83). Visceral abscesses (26/83) and skin infections (24/83) were the common sites of infection. Methicillin-resistant Staphylococcus aureus was the most common pathogen. The dominant or codominant deposition of IgA or C3 along the glomeruli was an important feature identified by immunofluorescence. There were 19 patients (22.9%) that progressed to dialysis-dependent ESRD. Twelve patients (14.5%) died. A univariate regression analysis indicated that diabetes mellitus (DM) (odds ratio [OR] 2.96; 95% confidence interval [CI] 1.03-8.48; P = 0.04) and age (OR 4.80; 95% CI 1.84-12.53; P = 0.001) were risk factors for ESRD or death. A multivariate regression analysis also revealed that age (OR 4.90; 95% CI 1.82-13.18; P = 0.002) and DM (OR 3.07; 95% CI 0.98-9.59; P = 0.05) were independent risk factors for unfavorable prognosis. Glomerulonephritis related to staphylococcal infection has different features than typical postinfectious glomerulonephritis. The diagnosis of glomerulonephritis related to staphylococcal infection relies on immunofluorescence and electron microscopy findings. Age and DM are independent risk factors of poor prognosis for glomerulonephritis related to staphylococcal infection.

Background: Acute kidney injury (AKI) is associated with damage to the nephrons and tubular epithelial cells (TECs), which can lead to chronic kidney disease and end-stage renal disease. Identifying new biomarkers before kidney dysfunction will offer crucial insight into preventive and therapeutic options for the treatment of AKI. Early growth response 1 (EGR1) has been found to be a pioneer transcription factor that can sequentially turn on/off key downstream genes to regulate whole-body regeneration processes in the leopard worm. Whether EGR1 modulates renal regeneration processes in AKI remains to be elucidated. Methods: AKI models of ischemia-reperfusion injury (IRI) and folic acid (FA) were developed to investigate the roles of EGR1 in kidney injury and regeneration. To further determine the function of EGR1, Egr1-/- mice were applied. Furthermore, RNA sequencing of renal TECs, Chromatin Immunoprecipitation (ChIP) assay, and Dual-luciferase reporter assay were carried out to investigate whether EGR1 affects the expression of SOX9. Results: EGR1 is highly expressed in the kidney after AKI both in humans and mice through analysis of the Gene Expression Omnibus (GEO) database. Furthermore, we verified that EGR1 rapidly up-regulates in the very early stage of IRI and nephrotoxic models of AKI, and validation studies confirmed the essential roles of EGR1 in renal tubular cell regeneration. Further experiments affirmed that genetic inhibition of Egr1 aggravates the severity of AKI in mouse models. Furthermore, our results revealed that EGR1 could increase SOX9 expression in renal TECs by directly binding to the promoter of the Sox9 gene, thus promoting SOX9+ cell proliferation by activating the Wnt/β-catenin pathway. Conclusions: Together, our results demonstrated that rapid and transient induction of EGR1 plays a renoprotective role in AKI, which highlights the prospects of using EGR1 as a potential therapeutic target for the treatment of AKI.