Inhibition of intracellular clusterin attenuates cell death in nephropathic cystinosis

Construction of 2DE Patterns of Plasma Proteins: Aspect of Potential Tumor Markers

The use of tumor markers aids in the early detection of cancer recurrence and prognosis. There is a hope that they might also be useful in screening tests for the early detection of cancer. Here, the question of finding ideal tumor markers, which should be sensitive, specific, and reliable, is an acute issue. Human plasma is one of the most popular samples as it is commonly collected in the clinic and provides noninvasive, rapid analysis for any type of disease including cancer. Many efforts have been applied in searching for “ideal” tumor markers, digging very deep into plasma proteomes. The situation in this area can be improved in two ways—by attempting to find an ideal single tumor marker or by generating panels of different markers. In both cases, proteomics certainly plays a major role. There is a line of evidence that the most abundant, so-called “classical plasma proteins”, may be used to generate a tumor biomarker profile. To be comprehensive these profiles should have information not only about protein levels but also proteoform distribution for each protein. Initially, the profile of these proteins in norm should be generated. In our work, we collected bibliographic information about the connection of cancers with levels of “classical plasma proteins”. Additionally, we presented the proteoform profiles (2DE patterns) of these proteins in norm generated by two-dimensional electrophoresis with mass spectrometry and immunodetection. As a next step, similar profiles representing protein perturbations in plasma produced in the case of different cancers will be generated. Additionally, based on this information, different test systems can be developed.

Programmed Cell Death in Cystinosis

Cystinosis is a lethal autosomal recessive disease that has been known clinically for over 100 years. There are now specific treatments including dialysis, renal transplantation and the orphan drug, cysteamine, which greatly improve the duration and quality of patient life, however, the cellular mechanisms responsible for the phenotype are unknown. One cause, programmed cell death, is clearly involved. Study of extant literature via Pubmed on “programmed cell death” and “apoptosis” forms the basis of this review. Most of such studies involved apoptosis. Numerous model systems and affected tissues in cystinosis have shown an increased rate of apoptosis that can be partially reversed with cysteamine. Proposed mechanisms have included changes in protein signaling pathways, autophagy, gene expression programs, and oxidative stress.

Susceptibility to disease (tropical theileriosis) is associated with differential expression of host genes that possess motifs recognised by a pathogen DNA binding protein

Background

Knowledge of factors that influence the outcome of infection are crucial for determining the risk of severe disease and requires the characterisation of pathogen-host interactions that have evolved to confer variable susceptibility to infection. Cattle infected by Theileria annulata show a wide range in disease severity. Native (Bos indicus) Sahiwal cattle are tolerant to infection, whereas exotic (Bos taurus) Holstein cattle are susceptible to acute disease.

Methodology/Principal findings

We used RNA-seq to assess whether Theileria infected cell lines from Sahiwal cattle display a different transcriptome profile compared to Holstein and screened for altered expression of parasite factors that could generate differences in host cell gene expression.

Significant differences (<0.1 FDR) in the expression level of a large number (2211) of bovine genes were identified, with enrichment of genes associated with Type I IFN, cholesterol biosynthesis, oncogenesis and parasite infection. A screen for parasite factors found limited evidence for differential expression. However, the number and location of DNA motifs bound by the TashAT2 factor (TA20095) were found to differ between the genomes of B. indicus vs. B. taurus, and divergent motif patterns were identified in infection-associated genes differentially expressed between Sahiwal and Holstein infected cells.

Conclusions/Significance

We conclude that divergent pathogen-host molecular interactions that influence chromatin architecture of the infected cell are a major determinant in the generation of gene expression differences linked to disease susceptibility.

Prediction of drug-induced kidney injury in drug discovery

Drug induced kidney injury is one of the leading causes of failure of drug development programs in the clinic. Early prediction of renal toxicity potential of drugs is crucial to the success of drug candidates in the clinic. The dynamic nature of the functioning of the kidney and the presence of drug uptake proteins introduce additional challenges in the prediction of renal injury caused by drugs. Renal injury due to drugs can be caused by a wide variety of mechanisms and can be broadly classified as toxic or obstructive. Several biomarkers are available for in vitro and in vivo detection of renal injury. In vitro static and dynamic (microfluidic) cellular models and preclinical models can provide valuable information regarding the toxicity potential of drugs. Differences in pharmacology and subsequent disconnect in biomarker response, differences in the expression of transporter and enzyme proteins between in vitro to in vivo systems and between preclinical species and humans are some of the limitations of current experimental models. The progress in microfluidic (kidney-on-chip) platforms in combination with the ability of 3-dimensional cell culture can help in addressing some of these issues in the future. Finally, newer in silico and computational techniques like physiologically based pharmacokinetic modeling and machine learning have demonstrated potential in assisting prediction of drug induced kidney injury.

Netrin-1 and clusterin: Innovative potential diagnostic biomarkers for early renal damage in β-thalassemia major children

BACKGROUND

Children with β-thalassemia major (β-TM) suffer from tubular dysfunction even before the onset of any renal impairment symptoms and/or clinical signs. Therefore, identifying innovative biomarkers allowing early renal damage detection has focused attention.

AIM

This study aims to preliminary assess Netrin-1(NTN-1) and clusterin (CLU) in β-TM children and explore their possible roles as surrogate noninvasive biomarkers of renal tubular dysfunction.

SUBJECTS AND METHODS

In this study, 40 β-TM children and 30 healthy children were enrolled. Routine serum and urinary biochemical variables were determined. Urinary NTN-1 and CLU levels were measured using ELISA and their mRNA expression in PBMCs were assayed using real-time PCR. Serum TNF-α, MDA levels and GST activity were measured.

RESULTS

Urinary NTN-1 and CLU concentrations and mRNA relative expression levels in PBMCs were significantly increased in β-TM children relative to controls. Oxidative stress and inflammatory markers revealed significant elevation in β-TM children compared to controls. The change in these parameters correlated significantly with other renal parameters. ROC curves analysis showed that urinary NTN-1 and CLU levels are of promising diagnostic performance.

CONCLUSION

Our results suggest that NTN-1 and CLU are qualified as new noninvasive biomarker panels for early detection of renal injury in β-TM children. Moreover, urinary NTN-1 is recommended as a precise one during the clinical practices.

Clusterin regulates macrophage expansion, polarization and phagocytic activity in response to inflammation in the kidneys

Clusterin (CLU) is a multifunctional protein localized extracellularly and intracellularly. Although CLU-knockout (KO) mice are more susceptible to renal ischemia-reperfusion injury (IRI), the mechanisms underlying the actions of CLU in IRI are not fully understood. Macrophages are key regulators of IRI severity and tissue repair. Therefore, we investigated the role of CLU in macrophage polarization and phagocytosis. Renal IRI was induced in wild-type (WT) or CLU-KO C57BL/6 mice by clamping the renal pedicles for 30 min at 32°C. Peritoneal macrophages were activated via an intraperitoneal injection of lipopolysaccharide (LPS). Renal tissue damage was examined using histology, whereas leukocyte phenotypes were assessed using flow cytometry and immunohistochemistry. We found that monocytes/macrophages expressed the CLU protein that was upregulated by hypoxia. The percentages of macrophages (F4/80⁺ , CD11b⁺ or MAC3⁺ ) infiltrating the kidneys of WT mice were significantly less than those in CLU-KO mice after IRI. The M1/M2 phenotype ratio of the macrophages in WT kidneys decreased at day 7 post-IRI when the injury was repaired, whereas that in KO kidneys increased consistently as tissue injury persisted. In response to LPS stimulation, WT mice produced fewer M1 macrophages, but not M2, than the control did. Phagocytosis was stimulated by CLU expression in macrophages compared with the CLU null controls and by the exogenous CLU protein. In conclusion, CLU suppresses macrophage infiltration and proinflammatory M1 polarization during the recovery period following IRI, and enhances phagocytic activity, which may be partly responsible for tissue repair in the kidneys of WT mice after injury.

Review of proteomics approach to eye diseases affecting the anterior segment

Visual impairment and blindness is a major health burden worldwide, and major ocular diseases causing visual impairment pertain to the anterior segment of the eye. Anterior segment ocular diseases are common, yet complex entities. Although many treatment options and surgical techniques are available for these ailments, the underlying cause and pathogenesis is still unclear. Finding ways to fundamentally treat these patients and rectify the underlying dysregulations leading to the disease may help cure patients completely without major complications. Proteomics approaches are a novel way to distinguish dysregulated proteins in a variety of biological tissues in a hypothesis-free manner, thus helping to find the responsible pathways leading to a certain disease. The aim of the current study is to review the available knowledge in scientific literature regarding the proteomics studies done on anterior segment eye diseases and suggest potential clinical implications to exploit the results of these studies. SIGNIFICANCE: Anterior segment ocular diseases are responsible for a major proportion of visual impairment and blindness worldwide. Although ophthalmologists have several treatment options that can alleviate or control the progression of these diseases, no definite cure is available for most of them. Moreover, because these diseases are progressive, prompt diagnosis is of utmost important. Proteomics studies enable us to identify and quantify the dysregulated proteins in a biological specimen in a hypothesis-free manner. Understanding the dysregulated protein pathways shines a light on the pathogenesis of the disease. Moreover, these dysregulated proteins may act as biomarkers to help in diagnosis and treatment follow-up. Hence, in this article we sought out to review the available scientific literature regarding the proteomics studies of anterior segment ocular diseases and to identify potential applications of proteomic studies in clinic.

Plasma Osteopontin Levels is Associated with Biochemical Markers of Kidney Injury in Patients with Leptospirosis

Leptospirosis becomes severe, with a fatality rate of >10%, and manifests as severe lung injury accompanied by acute kidney injury. Using urine and blood samples of 112 patients with leptospirosis, osteopontin (OPN), galectin-9 (Gal-9) and other kidney-related biomarkers were measured to understand the pathological and diagnostic roles of OPN and Gal-9 in leptospirosis. Plasma levels of full-length (FL)-OPN (pFL-OPN) (p < 0.0001), pFL-Gal-9(p < 0.0001) and thrombin-cleaved OPN (p < 0.01) were significantly higher in patients with leptospirosis than in healthy controls (n = 30), as were levels of several indicators of renal toxicity: serum cystatin C (p < 0.0001), urine N-acetyl-β-glucosaminidase (NAG)/creatinine (p < 0.05), and urine clusterin/creatinine (p < 0.05). pFL-Gal-9 levels were negatively correlated with pFL-OPN levels (r = −0.24, p < 0.05). pFL-OPN levels were positively correlated with serum cystatin C (r = 0.41, p < 0.0001), urine NAG/creatinine (r = 0.35, p < 0.001), urine clusterin/creatinine (r = 0.33, p < 0.01), and urine cystatin C/creatinine (r = 0.33, p < 0.05) levels. In a group of patients with abnormally high creatinine levels, significantly higher levels of serum cystatin C (p < 0.0001) and pFL-OPN (p < 0.001) were observed. Our results demonstrate that pFL-OPN reflect kidney injury among patients with leptospirosis.

Regulation of TFEB activity and its potential as a therapeutic target against kidney diseases

The transcription factor EB (TFEB) regulates the expression of target genes bearing the Coordinated Lysosomal Expression and Regulation (CLEAR) motif, thereby modulating autophagy and lysosomal biogenesis. Furthermore, TFEB can bind to the promoter of autophagy-associated genes and induce the formation of autophagosomes, autophagosome-lysosome fusion, and lysosomal cargo degradation. An increasing number of studies have shown that TFEB stimulates the intracellular clearance of pathogenic factors by enhancing autophagy and lysosomal function in multiple kidney diseases, such as cystinosis, acute kidney injury, and diabetic nephropathy. Taken together, this highlights the importance of developing novel therapeutic strategies against kidney diseases based on TFEB regulation. In this review, we present an overview of the current data on TFEB and its implication in kidney disease.

Transcriptomic Changes Related to Cellular Processes with Particular Emphasis on Cell Activation in Lysosomal Storage Diseases from the Group of Mucopolysaccharidoses

Although mucopolysaccharidoses (MPS), inherited metabolic diseases from the group of lysosomal storage diseases (LSD), are monogenic disorders, recent studies indicated that their molecular mechanisms are complicated. Storage of glycosaminoglycans (GAGs), arising from a deficiency in one of the enzymes involved in the degradation of these compounds, is the primary cause of each MPS type. However, dysfunctions of various cellular organelles and disturbance of cellular processes have been reported which contribute considerably to pathomechanisms of the disease. Here, we present a complex transcriptomic analysis in which all types and subtypes of MPS were investigated, with special emphasis on genes related to cell activation processes. Complex changes in expression of these genes were found in fibroblasts of all MPS types, with number of transcripts revealing higher or lower levels (relative to control fibroblasts) between 19 and over 50, depending on MPS type. Genes in which expression was significantly affected in most MPS types code for proteins involved in following processes, classified according to Gene Ontology knowledge database: cell activation, cell growth, cell recognition, and cell division. Levels of some transcripts (including CD9, CLU, MME and others) were especially significantly changed (over five times relative to controls). Our results are discussed in the light of molecular pathomechanisms of MPS, indicating that secondary and/or tertiary changes, relative to GAG storage, might significantly modulate cellular dysfunctions and contribute to molecular mechanisms of the disease. This may influence the efficacy of various therapies and suggests why various treatments are not fully effective in improving the complex symptoms of MPS.

Bovine HDL and Dual Domain HDL-Mimetic Peptides Inhibit Tumor Development in Mice

A growing body of literature supports the role of apolipoproteins present in HDL in the treatment of pro-inflammatory diseases including cancer. We examined whether bovine HDL (bHDL) and three dual-domain peptides, namely AEM-28 and its analog AEM-28-2, and HM-10/10, affect tumor growth and development in mouse models of ovarian and colon cancer. We demonstrate that bHDL inhibits mouse colorectal cancer cell line CT26-mediated lung tumor development, and mouse ovarian cancer cell line ID8-mediated tumor burden. We also demonstrate that, although to different degrees, dual-domain peptides inhibit cell viability of mouse and human ovarian and colon cancer cell lines, but not that of normal human colonic epithelial cells or NIH3T3 mouse fibroblasts. Dual-domain peptides administered subcutaneously or in a chow diet decrease CT26 cell-mediated tumor burden, tumor growth, and tumor dissemination in BALB/c mice. Plasma levels of lysophosphatidic acid (LPA) are significantly reduced in mice that received bHDL and the dual-domain peptides, suggesting that reduction by effecting accumulation and/or synthesis of pro-inflammatory lipids may be one of the mechanisms for the inhibition of tumor development by bHDL and the dual-domain peptides. Our studies suggest that therapeutics based on apolipoproteins present in HDL may be novel agents for the treatment of epithelial adenocarcinomas of the ovary and colon.

Clusterin in Alzheimer's Disease: Mechanisms, Genetics, and Lessons From Other Pathologies

Clusterin (CLU) or APOJ is a multifunctional glycoprotein that has been implicated in several physiological and pathological states, including Alzheimer's disease (AD). With a prominent extracellular chaperone function, additional roles have been discussed for clusterin, including lipid transport and immune modulation, and it is involved in pathways common to several diseases such as cell death and survival, oxidative stress, and proteotoxic stress. Although clusterin is normally a secreted protein, it has also been found intracellularly under certain stress conditions. Multiple hypotheses have been proposed regarding the origin of intracellular clusterin, including specific biogenic processes leading to alternative transcripts and protein isoforms, but these lines of research are incomplete and contradictory. Current consensus is that intracellular clusterin is most likely to have exited the secretory pathway at some point or to have re-entered the cell after secretion. Clusterin's relationship with amyloid beta (Aβ) has been of great interest to the AD field, including clusterin's apparent role in altering Aβ aggregation and/or clearance. Additionally, clusterin has been more recently identified as a mediator of Aβ toxicity, as evidenced by the neuroprotective effect of CLU knockdown and knockout in rodent and human iPSC-derived neurons. CLU is also the third most significant genetic risk factor for late onset AD and several variants have been identified in CLU. Although the exact contribution of these variants to altered AD risk is unclear, some have been linked to altered CLU expression at both mRNA and protein levels, altered cognitive and memory function, and altered brain structure. The apparent complexity of clusterin's biogenesis, the lack of clarity over the origin of the intracellular clusterin species, and the number of pathophysiological functions attributed to clusterin have all contributed to the challenge of understanding the role of clusterin in AD pathophysiology. Here, we highlight clusterin's relevance to AD by discussing the evidence linking clusterin to AD, as well as drawing parallels on how the role of clusterin in other diseases and pathways may help us understand its biological function(s) in association with AD.

Thirty Minutes of Hypobaric Hypoxia Provokes Alterations of Immune Response, Haemostasis, and Metabolism Proteins in Human Serum

Hypobaric hypoxia (HH) during airline travel induces several (patho-) physiological reactions in the human body. Whereas severe hypoxia is investigated thoroughly, very little is known about effects of moderate or short-term hypoxia, e.g. during airline flights. The aim of the present study was to analyse changes in serum protein expression and activation of signalling cascades in human volunteers staying for 30 min in a simulated altitude equivalent to airline travel. After approval of the local ethics committee, 10 participants were exposed to moderate hypoxia (simulation of 2400 m or 8000 ft for 30 min) in a hypobaric pressure chamber. Before and after hypobaric hypoxia, serum was drawn, centrifuged, and analysed by two-dimensional gel electrophoresis (2-DIGE) and matrix-assisted laser desorption/ionization followed by time-of-flight mass spectrometry (MALDI-TOF). Biological functions of regulated proteins were identified using functional network analysis (GeneMania®, STRING®, and Perseus® software). In participants, oxygen saturation decreased from 98.1 ± 1.3% to 89.2 ± 1.8% during HH. Expression of 14 spots (i.e., 10 proteins: ALB, PGK1, APOE, GAPDH, C1QA, C1QB, CAT, CA1, F2, and CLU) was significantly altered. Bioinformatic analysis revealed an association of the altered proteins with the signalling cascades "regulation of haemostasis" (four proteins), "metabolism" (five proteins), and "leukocyte mediated immune response" (five proteins). Even though hypobaric hypoxia was short and moderate (comparable to an airliner flight), analysis of protein expression in human subjects revealed an association to immune response, protein metabolism, and haemostasis.

Biomarkers associated with bronchopulmonary dysplasia/mortality in premature infants

BACKGROUND

Bronchopulmonary dysplasia (BPD) portends lifelong organ impairment and death. Our ability to predict BPD in first days of life is limited, but could be enhanced using novel biomarkers.

METHODS

Using an available clinical and urine biomarker database obtained from a prospective 113 infant cohort (birth weight ≤1,200 g and/or gestational age ≤31 wk), we evaluated the independent association of 14 urine biomarkers with BPD/mortality.

RESULTS

Two of the 14 urine biomarkers were independently associated with BPD/mortality after controlling for gestational age (GA), small for gestational age (SGA), and intubation status. The best performing protein was clusterin, a ubiquitously expressed protein and potential sensor of oxidative stress associated with lung function in asthma patients. When modeling for BPD/mortality, the independent odds ratio for maximum adjusted urine clusterin was 9.2 (95% CI: 3.3-32.8, P < 0.0001). In this model, clinical variables (GA, intubation status, and SGA) explained 38.3% of variance; clusterin explained an additional 9.2%, while albumin explained an additional 3.4%. The area under the curve incorporating clinical factors and biomarkers was 0.941.

CONCLUSION

Urine clusterin and albumin may improve our ability to predict BPD/mortality. Future studies are needed to validate these findings and determine their clinical usefulness.

Activation of the transcription factor EB rescues lysosomal abnormalities in cystinotic kidney cells

Nephropathic cystinosis is a rare autosomal recessive lysosomal storage disease characterized by accumulation of cystine into lysosomes secondary to mutations in the cystine lysosomal transporter, cystinosin. The defect initially causes proximal tubular dysfunction (Fanconi syndrome) which in time progresses to end-stage renal disease. Cystinotic patients treated with the cystine-depleting agent, cysteamine, have improved life expectancy, delayed progression to chronic renal failure, but persistence of Fanconi syndrome. Here, we have investigated the role of the transcription factor EB (TFEB), a master regulator of the autophagy-lysosomal pathway, in conditionally immortalized proximal tubular epithelial cells derived from the urine of a healthy volunteer or a cystinotic patient. Lack of cystinosin reduced TFEB expression and induced TFEB nuclear translocation. Stimulation of endogenous TFEB activity by genistein, or overexpression of exogenous TFEB lowered cystine levels within 24 hours in cystinotic cells. Overexpression of TFEB also stimulated delayed endocytic cargo processing within 24 hours. Rescue of other abnormalities of the lysosomal compartment was observed but required prolonged expression of TFEB. These abnormalities could not be corrected with cysteamine. Thus, these data show that the consequences of cystinosin deficiency are not restricted to cystine accumulation and support the role of TFEB as a therapeutic target for the treatment of lysosomal storage diseases, in particular of cystinosis.

Cystinosin-LKG rescues cystine accumulation and decreases apoptosis rate in cystinotic proximal tubular epithelial cells

BACKGROUND

Nephropathic cystinosis is a lysosomal storage disease that is caused by mutations in the CTNS gene encoding a cystine/proton symporter cystinosin and an isoform cystinosin-LKG which is generated by an alternative splicing of exon 12. We have investigated the physiological role of the cystinosin-LKG that is widely expressed in epithelial tissues.

METHODS

We have analyzed the intracellular localization and the function of the cystinosin-LKG conjugated with DsRed (cystinosin-LKG-RFP) in Madin-Darby canine kidney cells (MDCK II) and in proximal tubular epithelial cells carrying a deletion of the CTNS gene (cystinotic PTEC), respectively.

RESULTS

Cystinosin-LKG-RFP colocalized with markers of lysosomes, late endosomes and was also expressed on the apical surface of polarized MDCK II cells. Moreover, immune-electron microscopy images of MDCK II cells overexpressing cystinosin-LKG-RFP showed stacked lamellar membranes inside perinuclear lysosomal structures. To study the role of LKG-isoform, we have investigated cystine accumulation and apoptosis that have been described in cystinotic cells. Cystinosin-LKG decreased cystine levels by approximately 10-fold similarly to cystinosin-RFP. The levels of TNFα- and actinomycin D-inducted apoptosis dropped in cystinotic cells expressing LKG-isoform. This effect was also similar to the main isoform.

CONCLUSION

Our results suggest that cystinosin-LKG and cystinosin move similar functional activities in cells.

Clusterin as a therapeutic target

INTRODUCTION

Clusterin (CLU) is a stress-activated, ATP-independent molecular chaperone, normally secreted from cells, that is up-regulated in Alzheimer disease and in many cancers. It plays important roles in protein homeostasis/proteostasis, inhibition of cell death pathways, and modulation of pro-survival signalling and transcriptional networks. Changes in the CLU gene locus are highly associated with Alzheimer disease, and many therapy-resistant cancers over-express CLU. The extensive post-translational processing and heterogeneous oligomerization of CLU have so far prevented any definitive structure determination. This in turn has meant that targeting CLU with small molecule inhibitors is challenging. Therefore, inhibiting CLU at the gene-expression level using siRNA or antisense is a valid approach to inhibit its function. Areas covered: This article reviews recent advances regarding the role of CLU in proteostasis, cellular trafficking, human diseases, and signalling pathways involved in oncogenesis. It addresses the rationale for CLU as a therapeutic target in cancer, and the current status of pre-clinical and clinical studies using CLU antisense inhibitor OGX011. Expert opinion: Discusses challenges facing the therapeutic targeting of CLU including rapid changes in the treatment landscape for prostate cancer with multiple new FDA approved drugs, selection of windows of intervention, and potential side effects when silencing CLU expression.

Evaluation of liver cirrhosis and hepatocellular carcinoma using Protein-Protein Interaction Networks

AIM

In the current study, we analysised only the articles that investigate serum proteome profile of cirrhosis patients or HCC patients versus healthy controls.

BACKGROUND

Increased understanding of cancer biology has enabled identification of molecular events that lead to the discovery of numerous potential biomarkers in diseases. Protein-protein interaction networks is one of aspect that could elevate the understanding level of molecular events and protein connections that lead to the identification of genes and proteins associated with diseases.

METHODS

Gene expression data, including 63 gene or protein names for hepatocellular carcinoma and 29 gene or protein names for cirrhosis, were extracted from a number of previous investigations. The networks of related differentially expressed genes were explored using Cytoscape and the PPI analysis methods such as MCODE and ClueGO. Centrality and cluster screening identified hub genes, including APOE, TTR, CLU, and APOA1 in cirrhosis.

RESULTS

CLU and APOE belong to the regulation of positive regulation of neurofibrillary tangle assembly. HP and APOE involved in cellular oxidant detoxification. C4B and C4BP belong to the complement activation, classical pathway and acute inflammation response pathway. Also, it was reported TTR, TFRC, VWF, CLU, A2M, APOA1, CKAP5, ZNF648, CASP8, and HSP27 as hubs in HCC. In HCC, these include A2M that are corresponding to platelet degranulation, humoral immune response, and negative regulation of immune effector process. CLU belong to the reverse cholesterol transport, platelet degranulation and human immune response. APOA1 corresponds to the reverse cholesterol transport, platelet degranulation and humoral immune response, as well as negative regulation of immune effector process pathway.

CONCLUSION

In conclusion, this study suggests that there is a common molecular relationship between cirrhosis and hepatocellular cancer that may help with identification of target molecules for early treatment that is essential in cancer therapy.

Unique Cellular Lineage Composition of the First Gland of the Mouse Gastric Corpus

The glandular stomach has two major zones: the acid secreting corpus and the gastrin cell-containing antrum. Nevertheless, a single gland lies at the transition between the forestomach and corpus in the mouse stomach. We have sought to define the lineages that make up this gland unit at the squamocolumnar junction. The first gland in mice showed a notable absence of characteristic corpus lineages, including parietal cells and chief cells. In contrast, the gland showed strong staining of Griffonia simplicifolia-II (GSII)-lectin-positive mucous cells at the bases of glands, which were also positive for CD44 variant 9 and Clusterin. Prominent numbers of doublecortin-like kinase 1 (DCLK1) positive tuft cells were present in the first gland. The first gland contained Lgr5-expressing putative progenitor cells, and a large proportion of the cells were positive for Sox2. The cells of the first gland stained strongly for MUC4 and EpCAM, but both were absent in the normal corpus mucosa. The present studies indicate that the first gland in the corpus represents a unique anatomic entity. The presence of a concentration of progenitor cells and sensory tuft cells in this gland suggests that it may represent a source of reserve reparative cells for adapting to severe mucosal damage.

Relationship of clusterin with renal inflammation and fibrosis after the recovery phase of ischemia-reperfusion injury

Background

Long-term outcomes after acute kidney injury (AKI) include incremental loss of function and progression towards chronic kidney disease (CKD); however, the pathogenesis of AKI to CKD remains largely unknown. Clusterin (CLU) is a chaperone-like protein that reduces ischemia-reperfusion injury (IRI) and enhances tissue repair after IRI in the kidney. This study investigated the role of CLU in the transition of IRI to renal fibrosis.

Methods

IRI was induced in the left kidneys of wild type (WT) C57BL/6J (B6) versus CLU knockout (KO) B6 mice by clamping the renal pedicles for 28 min at the body temperature of 32 °C. Tissue damage was examined by histology, infiltrate phenotypes by flow cytometry analysis, and fibrosis-related gene expression by PCR array.

Results

Reduction of kidney weight was induced by IRI, but was not affected by CLU KO. Both WT and KO kidneys had similar function with minimal cellular infiltration and fibrosis at day 14 of reperfusion. After 30 days, KO kidneys had greater loss in function than WT, indicated by the higher levels of both serum creatinine and BUN in KO mice, and exhibited more cellular infiltration (CD8 cells and macrophages), more tubular damage and more severe tissue fibrosis (glomerulopathy, interstitial fibrosis and vascular fibrosis). PCR array showed the association of CLU deficiency with up-regulation of CCL12, Col3a1, MMP9 and TIMP1 and down-regulation of EGF in these kidneys.

Conclusion

Our data suggest that CLU deficiency worsens renal inflammation and tissue fibrosis after IRI in the kidney, which may be mediated through multiple pathways.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-016-0348-x) contains supplementary material, which is available to authorized users.

Autophagy in renal diseases

Autophagy is the cell biology process in which cytoplasmic components are degraded in lysosomes to maintain cellular homeostasis and energy production. In the healthy kidney, autophagy plays an important role in the homeostasis and viability of renal cells such as podocytes and tubular epithelial cells and of immune cells. Recently, evidence is mounting that (dys)regulation of autophagy is implicated in the pathogenesis of various renal diseases, and might be an attractive target for new renoprotective therapies. In this review, we provide an overview of the role of autophagy in kidney physiology and kidney diseases.

Requirement of clusterin expression for prosurvival autophagy in hypoxic kidney tubular epithelial cells

Cellular autophagy is a prosurvival mechanism in the kidney against ischemia-reperfusion injury (IRI), but the molecular pathways that activate the autophagy in ischemic kidneys are not fully understood. Clusterin (CLU) is a chaperone-like protein, and its expression is associated with kidney resistance to IRI. The present study investigated the role of CLU in prosurvival autophagy in the kidney. Renal IRI was induced in mice by clamping renal pedicles at 32°C for 45 min. Hypoxia in renal tubular epithelial cell (TEC) cultures was induced by exposure to a 1% O2 atmosphere. Autophagy was determined by either light chain 3-BII expression with Western blot analysis or light chain 3-green fluorescent protein aggregation with confocal microscopy. Cell apoptosis was determined by flow cytometric analysis. The unfolded protein response was determined by PCR array. Here, we showed that autophagy was significantly activated by IRI in wild-type (WT) but not CLU-deficient kidneys. Similarly, autophagy was activated by hypoxia in human proximal TECs (HKC-8) and WT mouse primary TECs but was impaired in CLU-null TECs. Hypoxia-activated autophagy was CLU dependent and positively correlated with cell survival, and inhibition of autophagy significantly promoted cell death in both HKC-8 and mouse WT/CLU-expressing TECs but not in CLU-null TECs. Further experiments showed that CLU-dependent prosurvival autophagy was associated with activation of the unfolded protein response in hypoxic kidney cells. In conclusion, these data suggest that activation of prosurvival autophagy by hypoxia in kidney cells requires CLU expression and may be a key cytoprotective mechanism of CLU in the protection of the kidney from hypoxia/ischemia-mediated injury.