Spatial proteomics landscape and immune signature analysis of renal sample of lupus nephritis based on laser-captured microsection.

OBJECTIVE: We aimed to reveal a spatial proteomic and immune signature of kidney function regions in lupus nephritis (LN). MATERIAL AND METHODS: The laser capture microdissection (LCM) was used to isolate the glomerulus, tubules, and interstitial of the kidney from paraffin samples. The data-independent acquisition (DIA) method was used to collect proteomics data. The bioinformatic analysis was performed. RESULTS: A total of 49,658 peptides and 4056 proteins were quantitated. Our results first showed that a high proportion of activated NK cells, naive B cells, and neutrophils in the glomerulus, activated NK cells in interstitial, and resting NK cells were accumulated in tubules in LN. The immune-related function analysis of differential expression proteins in different regions indicated that the glomerulus and interstitial were major sites of immune disturbance and regulation connected with immune response activation. Furthermore, we identified 7, 8, and 9 hub genes in LN's glomerulus, renal interstitial, and tubules. These hub genes were significantly correlated with the infiltration of immune cell subsets. We screened out ALB, CTSB, LCN2, A2M, CDC42, VIM, LTF, and CD14, which show higher performance as candidate biomarkers after correlation analysis with clinical indexes. The function within three regions of the kidney was analyzed. The differential expression proteins (DEGs) between interstitial and glomerulus were significantly enriched in the immune-related biological processes, and myeloid leukocyte-mediated immunity and cellular response to hormone stimulus. The DEGs between tubules and glomerulus were significantly enriched in cell activation and leukocyte-mediated immunity. While the DEGs between tubules and interstitial were enriched in response to lipid, antigen processing, and presentation of peptide antigen response to oxygen-containing compound, the results indicated a different function within kidney regions. CONCLUSIONS: Collectively, we revealed spatial proteomics and immune signature of LN kidney regions by combined using LCM and DIA.

miR-23b Attenuates LPS-Induced Inflammatory Responses in Acute Lung Injury via Inhibition of HDAC2.

Inflammatory responses play significant role in infectious etiology-induced acute lung injury (ALI). Histone deacetylase 2 is found to be essential and stimulated in lipopolysaccharide (LPS)-induced ALI by regulating proinflammatory cytokines. miR-23b has been demonstrated to be downregulated in LPS-induced inflammatory injury. In this study, we aimed to explore the interaction between miR-23b and HDAC2 and their function in LPS-induced ALI. LPS treatment was induced on murine alveolar macrophage cell line MH-S. Level of miR-23b and HDAC2 were determined by real-time PCR or Western blot. Proinflammatory cytokines expression and secretion were detected by real-time PCR and ELISA assay. The levels of miR-23b and HDAC2 were manipulated by transient transfection of miRNA mimics, shRNA or overexpression vector. The interaction between miR-23b and HDAC2 were tested by Luciferase reporter assay. LPS treatment inhibited miR-23b expression, while increased HDAC2 level in MH-S cells. Proinflammatory cytokines were stimulated by LPS treatment. Knockdown of HDAC2 or overexpression of miR-23b significantly repressed the expression of proinflammatory cytokines induced by LPS. miR-23b could suppress HDAC2 expression by directly targeting to its mRNA. LPS treatment stimulated the inflammatory responses in macrophages through inhibition of miR-23b, enhanced HDAC2 expression and inducing the expression of its downstream targets TNF-α, IL-6, and IL-1ß. Overexpression of miR-23b was sufficient to suppress inflammatory responses by targeting HDAC2, making it a promising therapeutic target to ALI treatment.

Evaluating the oil production and wastewater treatment efficiency by an extended two-stage network structure model with feedback variables.

Oil is an indispensable and important energy source in modern society, and oil production plays a vital role in economic development. However, there is no denying that oil production has a very bad impact on the environment. To realize the sustainable development of oil production, the environmental problems caused by oil production need to be controlled and managed strictly. Aiming at the practical problems of insufficient recoverable reserves of high quality oil and aggravating environmental pollution, efficient oil production and wastewater treatment become more and more important. Therefore, the whole system is divided into two stages. The stage 1 is oil development, and the stage 2 is wastewater treatment. Considering that the model needs to solve the undesirable output, an extended two-stage Slacks-Based Measure (SBM) Data Envelopment Analysis (DEA) network structure model with a feedback variable is established. The efficiency value of each stage can be obtained, and the weakness of each stage can be identified, so that the efficiency value of the whole system is more accurate. And then thirteen oilfields are selected for the numerical analysis to verify the validity and accuracy of the proposed model, the results demonstrate that the overall system is efficient only if the two stages are efficient; the oil production has higher efficiencies than the oilfield wastewater treatment; There is a stronger relationship between the efficiency of oilfield wastewater treatment and the whole system. A comparison with a traditional model demonstrated that the proposed model has a more scientific, stable and practical evaluation methods.

3D pose estimation of large and complicated workpieces based on binocular stereo vision.

A binocular stereo vision method is proposed for automatically locating the position and posture of workpieces, which is especially important when processing large, complicated structures, for example, the laser hardening and laser cladding of automotive die. First, a binocular stereo vision positioning system was designed and modeled, from which a method of background subtraction was proposed to extract the edge line of the foreground area. Furthermore, the intersection point of the workpiece contour line was taken as the characteristic point of the workpiece, and an algorithm that combines epipolar constraint with gray value similarity was proposed to quickly and accurately realize the feature points matching. Finally, experiments show that the workpiece can be positioned accurately, and that the precision of position recognition could be controlled within ±0.5 mm when the camera was 1 m away from the workpiece, meeting the requirement of robot processing.

Study on the Spatial Damage Characteristics of Working Fluid in a Sandstone Reservoir and an Unplugged Fluid System.

Due to its good physical properties and low pressure coefficient, the K75 reservoir is prone to leakage and intrusion of drilling and completion fluids during well construction, resulting in plugging of the borehole throat, which will inevitably affect the injection and recovery capacity of the gas well. In order to ensure the strong injection and production capacity of the K75 reservoir, this paper clarifies the reservoir space damage characteristics under different pressure differences and different entry fluids by establishing physical simulation of the damage, selecting the optimal system of the decongestant, and conducting dynamic flow decongestion experiments, as well as combining with the characterization means of the continuous scanning system of the core and the permeability test of the gas measurement. The test results show that the degree of damage of the same working fluid increases with the increase of differential pressure of repulsion, and the degree of damage of sequential working fluids (drilling fluid, completion fluid, and perforating fluid) is greater than that of drilling fluid damage under the same differential pressure of repulsion. In order to relieve the damage of wellbore working fluids, a set of multifunctional, low-corrosion composite acid system formulas was selected through rock powder, mud cake dissolution experiments, and dynamic flow unblocking experiments; the permeability recovery rate of this acid system after unblocking was more than 90%, which is widely applicable, and it is useful for the acidizing and unblocking practice in similar reservoirs.

Unblocking Process of Complex Sulfur-Iron Scale Blockage in Sulfur-Bearing Gas Wells and Its Mechanism.

In this paper, through the establishment of a blockage analysis process, multistage weight loss method, and FT-IR, GC-MS, SEM, EDS, XRD and other characterization test means, it is clear that the scale sample is mainly organic material covered with complex and diverse sulfur and iron compounds, and the mechanism of sulfur-containing gas well blockage is revealed by tracing into the well material, formation minerals, acid gas corrosion, and other substances. Through the selection of chelating agent, cleaning agent, and acid concentration, as well as the optimization of different process parameters, the "dispersion-chelation-dissolution" composite unblocking technology is proposed, and a set of unblocking formula systems for complex sulfur and iron scale is clarified. Finally, XRD and SEM characterization tests of the scale samples before and after dissolution were conducted to study the declogging mechanism and confirm the acid-insoluble nature of FeS2 and its stability in a weak acidic environment.

Global-feature of autoimmune glomerulonephritis using proteomic analysis of laser capture microdissected glomeruli.

Background: IgA nephropathy (IgAN), (LN), membranous nephropathy (MN), and minimal change nephropathy (MCN) are all belonged to autoimmune glomerulonephritis. This study aimed to identify the specific proteomic characteristics of the four GNs diseases in order to provide frameworks for developing the appropriate drug for patients diagnosed with GNs disease. Methods: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was utilized to investigate proteomic features of glomerular tissues obtained by laser capture microdissection (LCM). 8 normal control cases, 11 IgAN cases, 19 LN cases, 5 MN cases, and 3 MCN cases in this study were selected for bioinformatics analyses. Results: The shared overlapping proteins among the top 100 DEPs of each GNs type were mostly downregulated, in which only FLII was significantly downregulated in the four GNs diseases. A2M was significantly upregulated in MN, IgAN, and LN subgroups. The pathway of complement and coagulation cascades was notably activated with NES value ranging 2.77 to 3.39 among MCN, MN, IgAN, and LN diseases, but the pattern of protein expression level were significantly different. In LN patients, the increased activity of complement and coagulation cascades was contributed by the high expression of multiple complements (C1QB, C3, C4A, C4B, C6, C8B, C8G, C9). Meanwhile, both C1QC and C4B were remarkably upregulated in MN patients. On the contrary, complement-regulating proteins (CD59) was substantially decreased in MCN and IgAN subgroup. Conclusions: The integrative proteomics analysis of the four GNs diseases provide insights into unique characteristics of GNs diseases and further serve as frameworks for precision medicine diagnosis and provide novel targets for drug development.

Proteomic analysis of glomeruli, tubules and renal interstitium in idiopathic membranous nephropathy (IMN): A statistically observational study.

Idiopathic membranous nephropathy (IMN) is a common type of primary glomerulonephritis, which pathogenesis are highly involved protein and immune regulation. Therefore, we investigated protein expression in different microregions of the IMN kidney tissue. We used laser capture microdissection and mass spectrometry to identify the proteins in the kidney tissue. Using MSstats software to identify the differently expressed protein (DEP). Gene ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis were used to predict and enrich the potential functions of the DEPs, and DEPs were compared to the Public data in the gene expression omnibus (GEO) database for screening biomarkers of IMN. Immune infiltration analysis was used to analyze the immune proportion in IMN. Three significantly up-regulated proteins were identified in the glomeruli of patients with IMN; 9 significantly up-regulated and 6 significantly down-regulated proteins were identified in the interstitium of patients with IMN. Gene ontology analysis showed that the DEPs in the glomerulus and interstitium were mostly enriched in "biological regulation, the immune system, and metabolic processes." Kyoto Encyclopedia of Genes and Genomes analysis showed that the DEPs in the glomerulus and interstitium were mostly enriched in the "immune system" and the "complement and coagulation cascades. " According to the public information of the GEO database, DEPs in our study, Coatomer subunit delta Archain 1, Laminin subunit alpha-5, and Galectin-1 were highly expressed in the IMN samples from the GEO database; in the immune infiltration analysis, the proportion of resting memory CD4 T cells and activated NK cells in IMN were significantly higher than in the normal group. This study confirmed that there were significant differences in protein expression in different micro-regions of patients with IMN, The protein Coatomer subunit delta Archain 1, Laminin subunit alpha 5, Galectin-1 are potential biomarkers of IMN, the memory T cells CD4 and NK cells, maybe involved in the immunologic mechanism in the development of IMN.

Implantation underneath the abdominal anterior rectus sheath enables effective and functional engraftment of stem-cell-derived islets.

Human pluripotent stem cell-derived islets (hPSC islets) are a promising alternative to primary human islets for the treatment of insulin-deficient diabetes. We previously demonstrated the feasibility of this approach in nonhuman primates; however, the therapeutic effects of hPSC islets can be limited by the maladaptive processes at the transplantation site. Here, we demonstrate successful implantation of hPSC-derived islets in a new transplantation site in the abdomen, the subanterior rectus sheath, in eight nonhuman primates (five male and three female). In this proof-of-principle study, we find that hPSC islets survive and gradually mature after transplantation, leading to improved glycemic control in diabetic primates. Notably, C-peptide secretion responds to meal challenge from 6 weeks post-transplantation (wpt), with stimulation indices comparable to those of native islets. The average post-prandial C-peptide level reaches approximately 2.0 ng ml-1 from 8 wpt, which is five times higher than the peak value we previously obtained after portal vein infusion of hPSC islets and was associated with a decrease of glycated hemoglobin levels by 44% at 12 wpt. Although additional studies in larger cohorts involving long-term follow-up of transplants are needed, our results indicate that the subanterior rectus sheath supports functional maturation and maintenance of hPSC islets, suggesting that it warrants further exploration as a transplantation target site in the context of for hPSC-based cell-replacement therapies.

A New Compound Staged Gelling Acid Fracturing Method for Ultra-Deep Horizontal Wells.

Carbonate gas reservoirs in Sichuan are deeply buried, high temperature and strong heterogeneity. Staged acid fracturing is an effective means to improve production. Staged acidizing fracturing of ultra-deep horizontal wells faces the following problems: 1. Strong reservoir heterogeneity leads to the difficulty of fine segmentation; 2. The horizontal well section is long and running too many packers increases the completion risk; 3. Under high temperatures, the reaction speed between acid and rock is rapid and the acid action distance is short; and 4. The fracture conductivity is low under high-closure stress. In view of the above problems, the optimal fracture spacing is determined through productivity simulation. The composite temporary plugging of fibers and particles can increase the plugging layer pressure to 17.9 MPa, which can meet the requirements of the staged acid fracturing of horizontal wells. Through the gelling acid finger characteristic simulation and conductivity test, it is clear that the crosslinked authigenic acid and gelling acid in the Sichuan carbonate gas reservoir are injected alternately in three stages. When the proportion of gelling acid injected into a single section is 75% and the acid strength is 1.6 m3/m, the length and conductivity of acid corrosion fracture are the best. A total of 12 staged acid fracturing horizontal wells have been completed in the Sichuan carbonate gas reservoir, and the production is 2.1 times that of ordinary acid fracturing horizontal wells.

Label-free quantitative proteomic and phosphoproteomic analyses of renal biopsy tissues in membranous nephropathy.

PURPOSE: Membranous nephropathy (MN) is a common cause of nephrotic syndrome in adults. However, the underlying mechanisms of its occurrence and development are not completely clear. Thus, it is essential to explore the mechanisms. EXPERIMENTAL DESIGN: Here, we employed label-free quantification and liquid chromatography-tandem mass spectrometry analysis techniques to investigate the proteomic and phosphoproteomic alterations in renal biopsy tissues of MN patients. Samples were collected from 16 MN patients and 10 controls. Immunohistochemistry (IHC) was performed to validate the hub phosphoprotein. RESULTS: We focused on the changes in the phosphoproteome in MN group versus control group (CG). Totally, 1704 phosphoproteins containing 3241 phosphosites were identified and quantified. The phosphorylation levels of 216 phosphoproteins containing 297 phosphosites were differentially regulated in stage II MN group versus CG, and 333 phosphoproteins containing 461 phosphosites were differentially phosphorylated in stage III MN group versus CG. In each comparison, several differential phosphoproteins were factors, kinases and receptors involved in cellular processes, biological regulation and other biological processes. The subcellular location of most of the differential phosphoproteins was the nucleus. Protein-protein interaction analysis showed that the connections among the differential phosphoproteins were extremely complex, and several signalling pathways probably associated with MN were identified. The hub phosphoprotein was validated by IHC. CONCLUSIONS AND CLINICAL RELEVANCE: This investigation can provide direct insight into the global phosphorylation events in MN group versus CG and may help to shed light on the potential pathogenic mechanisms of MN.

Study on Filtration Performance of PVDF/PUL Composite Air Filtration Membrane Based on Far-Field Electrospinning.

At present, the situation of air pollution is still serious, and research on air filtration is still crucial. For the nanofiber air filtration membrane, the diameter, porosity, tensile strength, and hydrophilicity of the nanofiber will affect the filtration performance and stability. In this paper, based on the far-field electrospinning process and the performance effect mechanism of the stacked structure fiber membrane, nanofiber membrane was prepared by selecting the environmental protection, degradable and pollution-free natural polysaccharide biopolymer pullulan, and polyvinylidene fluoride polymer with strong hydrophobicity and high impact strength. By combining two kinds of fiber membranes with different fiber diameter and porosity, a three-layer composite nanofiber membrane with better hydrophobicity, higher tensile strength, smaller fiber diameter, and better filtration performance was prepared. Performance characterization showed that this three-layer composite nanofiber membrane had excellent air permeability and filtration efficiency, and the filtration efficiency of particles above PM 2.5 reached 99.9%. This study also provides important reference values for the preparation of high-efficiency composite nanofiber filtration membrane.

Uraemic serum induces dysfunction of vascular endothelial cells: role of ubiquitin-proteasome pathway.

The ubiquitin-proteasome pathway (UPP) has been indicated to contribute to dysfunction of endothelial cells (ECs). Nevertheless, the relationship between UPP and vascular complications of uraemia remains unknown. We aimed to determine whether the UPP is activated in vascular ECs when cultured with uraemic serum, and to examine the role of the UPP on dysfunction of ECs in uraemia. Rabbit aortic endothelial cells (RAECs) were cultured with normal serum or different concentrations of uraemic serum. The expression of the ubiquitin-activating enzyme (E1), an indicator of the UPP, was detected by real-time RT-PCR and Western blot; proteasome activity was determined by fluorescence spectrophotometry; and nuclear factor-κB (NF-κB) activity and expression, as well as tumour necrosis factor-α (TNF-α) expression, were also detected. We found that the expression of E1 and the activities of three kinds of proteasomes were increased significantly in RAECs after incubation with uraemic serum. Proliferation of RAECs was increased significantly by incubation with 3-15% uraemic serum but decreased markedly when incubated with uraemic serum above 15% (increased apoptosis). Incubation of RAECs with uraemic serum induced increased NF-B DNA-binding activity and nuclear translocation of NF-κB, decreased nitric oxide production and increased expression of TNF-α, which is the final effector of inflammatory activation of cells. All of these responses in RAECs were suppressed by the specific proteasome inhibitor, MG132. The inhibition of inflammatory responses by MG132 was further supported by a parallel experiment with pyrrolidine dithiocarbamate, a specific inhibitor of κNF-B. These findings suggest that the UPP was activated in RAECs by administration of uraemic serum, and played a pivotal role in the dysfunction of vascular ECs, such as inflammatory activation.

Large-Scale Acid Fracturing Based on a Large-Scale Conductivity Apparatus.

The conductivity of an acid-etched fracture is a necessary indicator for the stimulation of dolomite formation, which affects commercial development. The widely accepted test method involves the use of a small-scale conductivity cell for etching and measuring conductivity. However, the field production reflects that the actual conductivity does not match the measured one and is usually lower. Consequently, the existing studies had limitations and hence the stimulation mechanism needed to be explored further. To understand it more realistically, a novel large-scale apparatus was used in this study to test the conductivity of the acid-etched fracture. The use of this apparatus avoided the near-core excessive eroding and weak heterogeneity with continuous etching in a 1000 mm fracture. The results showed that the conductivity was indeed dissimilar to that in small-scale tests. The morphology of etched large-scale cores featured diversity and complexity, including deep and punctate channels, nonuniform pitting grooves with connected channels, and scale-shaped wavy grooves, which exactly demonstrated the multiple morphology under the influence of carbonate heterogeneity in real reservoirs. Moreover, the effect of increasing injection rate led to the unique etching morphology of scale-shaped wavy and pelviform grooves because of scouring flow and turbulence effects. The degree of surface roughness promoted nonuniform etching along the longitudinal and propagation direction, thus enhancing the conductivity of the whole fracture and confirming that the field treatment limited the pressure rather than the injection rate. The conductivity under different acid type, acid concentration, reaction temperature, and injection rate conditions was lower than that reported, confirming the experimental deviation in small-scale conductivity. The proposed large-scale apparatus test represented the acid-etched fracture conductivity more realistically, thus proving beneficial for the development of carbonate reservoirs.

Research and Application of Segmented Acid Fracturing by Temporary Plugging in Ultradeep Carbonate Reservoirs.

The ultradeep carbonate reservoir in Sichuan Basin is characterized by deep burial depth, high temperature, and strong heterogeneity. In the early stage of production, the vertical well acid fracturing is the main reservoir stimulation method, and the horizontal well stimulation technology is not mature enough to release the production capacity of gas wells. Segmented acid fracturing of the ultradeep horizontal wells currently faces the following problems: the strong heterogeneity of reservoir leads to the difficulty of fine segmentation; the high reservoir temperature requires higher performance of working fluid; the reaction rate between acid and rock is fast and the action distance of acid is short, and there is low fracture conductivity under high closure stress. In view of the above problems, the fine segmented design method was studied, and the high-temperature-resistant authigenic acid and gelling acid systems were developed. The viscosity of authigenic acid is greater than 150 mPa s after shearing at 160 °C and 170 s-1 for 50 min, and the highest acid generation concentration is 4.05 mol/L. The gelling acid system has both the properties of high-temperature resistance and low friction resistance; not only canit meet the requirements of the retarding rate and the corrosion inhibition ability when the reservoir temperature is 160 °C but also the resistance reduction rate is up to more than 70%. By alternating injection of authigenic acid and gelling acid, the acid-etched fracture length and conductivity were, respectively, increased by 80% and 45%. The application of this technology in the horizontal well of the ultradeep carbonate reservoir in Sichuan Basin can increase the productivity by 3 times when compared with the vertical well acid fracturing, and a better stimulation effect has been achieved.

Preparation and characterization of a self-suspending ultra-low density proppant.

A self-suspending ultra-low density proppant (UDP) was developed based on the polymerization of the unsaturated carbon double bond. Its performance was characterized by FT-IR and SEM, and the sphericity and roundness, diameter distribution, density, mechanical properties, the conductivity of the propped fracture, and mass loss of different fluids were measured. The test results indicated that the UDP no longer contained the unsaturated carbon double bond and the polymerization took place in the raw material. The fracture surface of UDP is compact and it is not easy to produce debris after compression failure. The sphericity and roundness of UDP were above 0.9, and the high sphericity and roundness provided high conductivity. The stirring speed has a great influence on the diameter of UDP, and the UDP with different sizes could be used to prop the hydraulic fracture to different widths. The average apparent density of UDP is as low as 1.044 g cm-3, and it can be suspended in the fracturing fluid for a long time. The strain in the UDP is higher than that in the ceramsite and quartz sand, but its crushing ratio is far below theirs; therefore, the conductivity of the fracture propped by UDP was higher than that of quartz sand and ceramsite. The solubility of UDP in kerosene, reservoir water, and hydrochloric acid is below 1%, indicating that the UDP is also suitable for acid fracturing with proppant. All the experimental results proved that the self-suspending ultra-low density proppant has great potential use in hydraulic fracturing and acid fracturing.

Evaluating the stability of prescription drugs in municipal wastewater and sewers based on wastewater-based epidemiology.

Wastewater-based epidemiology (WBE) is considered as an effective tool for monitoring drug consumption, which is often obtained by back-calculation using the influent concentration and other parameters of wastewater treatment plants. Lack of information on the transformation of drugs in municipal wastewater and sewers may lead to inaccurate consumption estimation. Fourteen prescription drugs in four major categories of diseases (cardiovascular, diabetes, depression, and asthma) were selected to study their adsorption and biodegradation in wastewater and biofilm sewers under different temperatures, pH and biofilms conditions. The result demonstrated that the decay percentage of drugs in wastewater is increased with temperature. Within 72 h, eleven of these 14 drugs, such as metformin, metoprolol, bezafibrate, etc., have decay percentages below 20% in wastewater, which are considered as stable drugs; and the decay percentages of the other three, monluster, paroxetine, and sertraline, are greater than 20%, which are the most unstable drugs. In lab-scale aerobic and anaerobic sewers, the decay percentages of metformin, glipizide, metoprolol, gemfibrozil, and atorvastatin are less than 20% within 24 h. The decay percentages of venlafaxine, citalopram, fluoxetine, salmeterol, and salbutamol within 24 h are 20%-60% and paroxetine and sertraline are close to or even exceed 80% within 6 h. Biodegradation of drugs in sewers with aerobic or anaerobic biofilms is higher than that in wastewater systems without biofilms. The results showed that when the per capita consumption of drugs is estimated by using the WBE method, the stability of drugs in wastewater and different types of sewers will significantly affect their residual concentrations.

Effects of 4-phenylbutyric acid on the process and development of diabetic nephropathy induced in rats by streptozotocin: regulation of endoplasmic reticulum stress-oxidative activation.

Oxidative stress may contribute to the pathogenesis of diabetic nephropathy (DN), although the precise regulatory mechanism is still unclear. Recent reports have shown that chemical molecular chaperone 4-phenylbutyric acid (4-PBA) can suppress oxidative stress by attenuating endoplasmic reticulum (ER) stress. We therefore hypothesized that 4-PBA could provide renoprotection through the suppression of oxidative stress in DN rats. Male Sprague-Dawley (SD) rats were randomly divided into three groups: a normal control (NC) group, a streptozotocin (STZ)-induced DN model group, and a DN plus 4-PBA (1g/kg) treatment group. At the end of 4, 8, and 12 weeks, hydroxyproline content, NADPH oxidase activity and the expression of phosphorylation of inositol-requiring enzyme-1alpha (p-IRE1alpha), p47phox, nitrotyrosine (NT) and NF-E2-related factor 2 (Nrf2) in the kidneys of all rats were determined; malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity in serum and urine were also detected; renal nuclear factor kappaB (NF-kappaB) activity in all of the rats was examined at the end of 12 weeks. Compared with the NC group, the DN rats showed a significant increase in hydroxyproline content, NADPH oxidase activity, NF-kappaB activity, the expression of p-IRE1alpha, p47phox, NT and Nrf2 in renal tissue; markedly, MDA levels were higher and SOD activity was lower in serum and urine of DN rats than in NC rats for the indicated time. These alterations were inhibited by the administration of 4-PBA. These findings first demonstrated that treatment with 4-PBA significantly inhibits the process and development of diabetic nephropathy in rats through the regulation of ER stress-oxidative activation.

Preventive effect of a proteasome inhibitor on the formation of accelerated atherosclerosis in rabbits with uremia.

Inflammation plays a central role in the pathogenesis of atherosclerosis. This study investigated whether the proteasome inhibitor has the same preventive effect on the formation of accelerated atherosclerosis in rabbits with uremia compared with a NF-kappaB inhibitor. New Zealand white rabbits were subjected to five-sixths nephrectomy (chronic renal failure [CRF]) or to a sham operation. Rats in each group were randomly assigned into three subgroups (n = 24 in each group) and treated with repeated intramuscular injections of proteasome inhibitor MG132 or NF-kappaB inhibitor PDTC for a specified period. Compared with sham rabbits, CRF rabbits displayed typical atherosclerotic changes (endothelial cell damage, intimal thickens, and appearance of foam cells). CRF rabbits had significantly higher levels of proteasome activity, NF-kappaB mRNA, protein, and DNA binding activity as well as tumor necrosis factor-a and proliferative cell nuclear antigen protein expression in aortic wall cells. CRF rabbits also showed lower levels of IkappaBalpha. Compared with CRF rabbits, CRF rabbits treatment with proteasome inhibitor MG132 showed restoration of IkappaBalpha mRNA and protein expression and decreased NF-kappaB DNA binding activity and tumor necrosis factor-a expression. Treatment with either proteasome inhibitor MG132 or NF-kappaB inhibitor PDTC could reverse these pathologic changes in the aortic wall cells of CRF rabbits. A comparison between the inhibitory effects of the two treatments revealed no statistical difference. These results suggest that ubiquitin-proteasome activation play a pivotal role in the pathogenesis of uremia-accelerated atherosclerosis. The ubiquitin-proteasome signaling pathway in aortic cells may therefore be an important target for preventing uremia-accelerated atherosclerosis.

Differential expression of transfer RNA-derived small RNAs in IgA nephropathy.

BACKGROUND: IgA nephropathy (IgAN) is one of the most common forms of primary glomerulonephritis. Recent studies have indicated that small noncoding RNAs, such as tRNA-derived small RNAs (tsRNAs), might be novel biomarkers for glomerulonephritis. We therefore investigated the potential roles and possible functions of the tsRNAs in IgAN. METHOD: Peripheral blood mononuclear cells (PBMCs) were extracted from blood samples of the patients with IgAN and healthy control groups. The expression profiles of tsRNAs were assessed by small RNA sequencing (RNA-Seq) in PBMCs of the IgAN and control groups. Dysregulated tsRNAs were selected for validation by quantitative real-time polymerase chain reaction (qRT-PCR). Target gene prediction and enrichment were performed by bioinformatics analysis. RESULTS: The results revealed that 143 significantly upregulated and 202 significantly downregulated tsRNAs were differentially altered in the IgAN group compared with the control group. Five upregulated tsRNAs (tRF-Val-AAC-007, tRF-Ala-AGC-063, tRF-Gln-CTG-010, tRF-Tyr-GTA-011 and tRF-Thr-AGT-007) and 3 downregulated tsRNAs (tiRNA-Val-TAC-004, tRF-Gly-CCC-005 and tRF-His-GTG-006) were selected for validation by qRT-PCR; the results were consistent with the sequencing data. Gene Ontology (GO) analysis revealed that the target genes predicted by upregulated tsRNAs were mostly enriched in "nucleic acid metabolic process,' "intracellular part,' and "ion binding,' whereas the target genes predicted by downregulated tsRNAs were mostly enriched in "regulation of cellular component organization,' "membrane-bound organelle,' and "ion binding.' Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the target genes predicted by upregulated tsRNAs were mostly enriched in "herpes simplex virus 1 infection,' whereas the target genes predicted by downregulated tsRNAs were mostly enriched in "circadian rhythm CONCLUSIONS:: The present study confirmed the differential expression of tsRNAs in patients with IgAN, and these dysregulated tsRNAs might be novel potential targets for the diagnosis and treatment of IgAN.