Effects of chronic kidney disease on cognitive function and α-klotho expression in hippocampus.

Background: Alpha-klotho (α-KL) is not only related to the regulation of calcium-phosphorus metabolism, and fibrosis in chronic kidney disease (CKD), it is also involved in the regulation of many cognitive disorders. We conducted this study to investigate the effects of CKD on cognitive dysfunction and α-KL. Methods: Doxorubicin was used to induce a CKD model, which was validated by weight, 24-hour urine protein quantification, serum creatinine (Cr), blood urea nitrogen (BUN), and kidney hematoxylin-eosin (HE) staining. The Morris water maze (MWM) paradigm was used to assess the effects of CKD on cognitive behavior. The expression of α-KL in the hippocampus was detected using real-time quantitative polymerase chain reaction, Western blot, and immunohistochemistry (IHC). Results: (I) In the CKD group, the weight of the rats increased slowly (P<0.001), 24-hour urine protein increased (P<0.05), and Cr (P=0.026) and BUN levels (P=0.003) increased; (II) HE staining showed that in the CKD group there were changes in the structure, fibrosis, and inflammatory infiltration of the renal tissues, and changes in the structure, cell necrosis, and neuronal degeneration of the hippocampus; (III) in the MWM experiment, the escape latency of the CKD group was prolonged compared to that of the control group (P=0.043, 0.023), and the number of crossing the platform was reduced (P=0.003); (IV) in the CKD group, the expressions of α-KL messenger ribonucleic acid (P=0.0005) and α-KL protein (P=0.0005) in the hippocampus were downregulated. The IHC results showed that the expression of α-KL protein in the hippocampal region III cornus ammonis (CA3) of the CKD group region was also downregulated, and the α-KL-positive cells (P=0.019) and mean optical density (P=0.015) were decreased. Conclusions: The expression of α-KL appears to effect the cognitive function of CKD rats; thus, it may be a valuable target in the treatment of CKD with cognitive impairment.

Tumor-Infiltrated CD8+ T Cell 10-Gene Signature Related to Clear Cell Renal Cell Carcinoma Prognosis.

Clear cell renal cell carcinoma (ccRCC) usually affects multiple organs (e.g., bone and brain), and patient prognosis is usually poor. Although it is known that CD8+ T cell infiltration can potentially alleviate ccRCC progression, few studies have concentrated on the correlation between CD8+ T cell infiltration and ccRCC prognosis. In this study, ten genes expressed by infiltrated CD8+ T cells (i.e., AMD1, CCSER2, CIB1, DRAP1, HMGB2, HMGN1, NPIPB5, PTP4A2, RORA, and SAP18) were suggested as potential ccRCC prognostic biomarkers, by using next-generation sequencing (i.e. bulk sequencing and single-cell sequencing) of ccRCC, papillary renal cell carcinoma (papRCC), and control kidney biopsies. Specifically, we identified four genes (i.e., CCSER2, DRAP1, NPIPB5, and SAP18) as potential novel prognostic biomarkers for ccRCC. It is noteworthy that SAP18 derived from CD8+ T cells negatively correlates to Atg7+ neutrophils in ccRCC, compared with papRCC, indicating a potential decreased neutrophil metabolic function in autophagy and fatty acids. This study elucidated the protective role of infiltrated CD8+ T cells in ccRCC and identified ten candidate genes related to an improved prognosis in patients with ccRCC.

Expression of LncRNA KCNQ1Ot1 in diabetic nephropathy and its correlation with MEK/ERK signaling pathway.

OBJECTIVE: To explore the expression of LncRNA KCNQ1OT1 in diabetic nephropathy (DN), and its correlation with MEK/ERK signaling pathway. METHODS: 148 patients with type 2 diabetes in our hospital were selected as research subjects, including 83 patients with simple type 2 diabetes (T2D group) and 65 patients with type 2 diabetes with DN (DN group). Another 50 non-diabetic patients were enrolled as the control group. The expressions of LncRNA KCNQ1OT1 and MEK/ERK signaling pathway related molecules in peripheral blood mononuclear cells (PBMCs) of the three groups of subjects were detected and their correlations were analyzed. In addition, 30 Wistar rats were divided into a control group, diabetes group and DN model group, and the expression of LncRNA KCNQ1OT1 and MEK/ERK signal pathway-related molecules in kidney tissue of the three groups was detected and compared. RESULTS: The relative expression of LncRNA KCNQ1OT1, MEK-5 and ERK2 in the control group was lower than that of the T2D group and DN group (P<0.05), and the relative expression of LncRNA KCNQ1OT1 in T2D group was lower than that of DN group (P<0.05). The expression of LncRNA KCNQ1OT1 was positively-correlated with MEK-5 and ERK2 (P<0.05). The relative expression of LncRNA KCNQ1OT1, MEK-5, and ERK2 in renal tissues of the DN group was higher than those in the control group and diabetes group (P<0.05). CONCLUSION: The expression of LncRNA KCNQ1OT1 in PBMCs of DN patients is abnormally increased, and may be a biomarker for the diagnosis and treatment of the disease. In addition, an abnormal increase of LncRNA KCNQ1OT1 is associated with the activation of the MEK/ERK signaling pathway.

Correlation of Carotid Artery Intima-Media Thickness with Calcium and Phosphorus Metabolism, Parathyroid Hormone, Microinflammatory State, and Cardiovascular Disease.

The internal thickness of the carotid artery is the vertical distance between the intima of the carotid artery and the middle mold. Its normal thickness is less than 1 mm. It can be used to judge the degree of arteriosclerosis. Under normal circumstances, the change of the internal thickness of the carotid artery is caused by cardiovascular disease. The purpose of this article is to study the relationship between the thickness of the carotid artery and the metabolism of calcium and phosphorus, parathyroid hormone, microinflammatory state, and cardiovascular disease. This article uses ultrasound measurement to measure the IMT of ESRD patients and carotid arteries with normal renal function. The analysis includes blood pressure, blood phosphorus, blood calcium, blood creatinine, blood urea nitrogen, blood sugar, glycosylated hemoglobin, blood lipids, parathyroid hormone, and C reaction. The correlation between clinical indicators includes protein and carotid IMT in ESRD patients which can be used in designing a diagnostic plan for patients through correlation research. The results showed that the carotid artery IMT of ESRD nondialysis patients was 13% thicker than that of those with normal renal function, and it was significantly positively correlated with age, blood pressure, blood phosphorus, glycosylated hemoglobin, and C-reactive protein. The correlation ratio with calcium and phosphorus was about 0.1.

Influence of sleep difficulty on post-traumatic stress symptoms among frontline medical staff during COVID-19 pandemic in China.

Being a nurse was demonstrated to be a risk factor for post-traumatic stress symptoms (PTS) and insomnia among frontline staff during COVID-19 pandemic. The unidirectional relationship between insomnia and PTS highly suggested that insomnia could mediate the increasing risk of PTS among frontline nurses. However, no study had tried to clarify this mediation effect of insomnia during COVID-19 pandemic. This study aimed to investigate prevalence of insomnia and PTS among frontline doctors and nurses and to clarify the relationship between career (doctor/nurses), insomnia and PTS. A total of 211 frontline doctors and nurses completed the investigation. Insomnia was measured using a self-drafted questionnaire and PTS was assessed using primary care post-traumatic stress disorder screen (PC-PTSD). Three logistics regression models and one mediation model were performed to explore relationships between career, insomnia and PTS. The prevalence of PTS (PC-PTSD≥2) and insomnia (with 1 item in self-drafted insomnia questionnaire≥2) was 24.17% and 36.97%, respectively. Being a nurse was a shared risk factor of insomnia (OR = 4.16, 95%CI: 1.30 ~ 5.77, P = 0.023) and PTS (OR = 7.51, 95%CI: 1.89 ~ 40.50, P = 0.008). Compared to doctors, nurses had significantly higher prevalence of insomnia (46.32% vs. 20%, χ2 = 13.27, P < 0.001) and PTS (30.14% vs. 13.33%, χ2 = 6.57, P = 0.011). Insomnia was a significant partial mediator (B = 0.101, P = 0.026), which explained 32.53% proportions of relationship between being a nurse and PTS. PTS and insomnia were common symptoms, which should be considered in psychological aids among frontline medical staff. Insomnia might be a possible target of PTS intervention.

The Identification of a Tumor Infiltration CD8+ T-Cell Gene Signature That Can Potentially Improve the Prognosis and Prediction of Immunization Responses in Papillary Renal Cell Carcinoma.

BACKGROUND: CD8+ T cells, vital effectors pertaining to adaptive immunity, display close relationships to the immunization responses to kill tumor cells. Understanding the effect exerted by tumor infiltration CD8+ T cells in papillary renal cell carcinoma (papRCC) is critical for assessing the prognosis process and responses to immunization therapy in cases with this disease. MATERIALS AND APPROACHES: The single-cell transcriptome data of papRCC were used for screening CD8+ T-cell-correlated differentially expressed genes to achieve the following investigations. On that basis, a prognosis gene signature associated with tumor infiltration CD8+ T cell was built and verified with The Cancer Genome Atlas data set. Risk scores were determined for papRCC cases and categorized as high- or low-risk groups. The prognosis significance for risk scores was assessed with multiple-variate Cox investigation and Kaplan-Meier survival curves. In addition, the possible capability exhibited by the genetic profiles of cases to assess the response to immunization therapy was further explored. RESULTS: Six hundred twenty-one cell death-inhibiting RNA genes were screened using single-cell RNA sequencing. A gene signature consisting of seven genes (LYAR, YBX1, PNRC1, TCF25, MYL12B, MINOS1, and LINC01420) was then identified, and this collective was considered to be an independent prognosis indicator that could strongly assess overall survival in papRCC. In addition, the data allowed papRCC cases to fall to cohorts at high and low risks, exhibiting a wide range of clinically related features as well as different CD8+ T-cell immunization infiltration and immunization therapy responses. CONCLUSIONS: Our work provides a possible explanation for the limited response of current immunization checkpoint-inhibiting elements for combating papRCC. Furthermore, the researchers built a novel genetic signature that was able to assess the prognosis and immunotherapeutic response of cases. This may also be considered as a promising therapeutic target for the disease.

S3-2, a novel long-lasting oxyntomodulin derivative, exerts improvement on diabesity and renal injury through activating GLP-1 and glucagon receptors.

AIMS: To prolong the short lifespan of oxyntomodulin (OXM) for treating obesity and diabetes, we designed a novel fused OXM analog, containing an albumin-binding sequence, a protease cleavable tetrapeptide, and a mutated OXM. MAIN METHODS: We screened two albumin-binding sequences (S3 and S6) to construct OXM derivatives, termed S3-2 (with two cysteines) and S6-0 (without cysteine). After peptides were synthesized, isothermal titration calorimetry (ITC) was applied to assess binding-affinity for HSA. Further in vivo acute efficacies evaluation and candidate selection were performed in diabetic db/db mice via oral glucose tolerance test (OGTT) and glucose-lowering duration test. Chronic efficacy test of selected candidate was also performed in diabetic mice. RESULTS: Firstly, S3-2 and S6-0 with purity over 99% were prepared. ITC measurements demonstrated that S3-2 and S6-0 associate with HSA with high-affinity (Kd = 12.81 ± 1.11 nM and 26.98 ± 2.39 nM, respectively). Then hypoglycemic efficacies showed deoxidation S3-2 (S3-2re) showed longer hypoglycemic duration than the oxidation one (S3-2ox), and better blood glucose level (BGL) control effect than S6-0. OGTTs in diabetic mice revealed the glucose-lowering efficacies of S3-2re were similar to Liraglutide. The protracted antidiabetic effects of S3-2re were further confirmed by multiple OGTTs in db/db mice. Furthermore, twice weekly injection of S3-2re to db/db mice achieved beneficial effects on body weight gain, glucose tolerance, postprandial BGL and obesity. Moreover, S3-2 produces significantly protective effects on the impaired renal functions of the diabetic mice. CONCLUSION: S3-2re exhibits outstanding therapeutical potential as a candidate drug for treating the obesity and diabetes.

Profiling the Resident and Infiltrating Monocyte/Macrophages during Rejection following Kidney Transplantation.

Immune tolerance research is essential for kidney transplantation. Other than antibody and T cell-mediated immune rejection, macrophage-mediated innate immunity plays an important role in the onset phase of transplantation rejection. However, due to the complexity of the kidney environment as well as its diversity and low abundance, studies pertaining to monocyte/macrophages in kidney transplantation require further elucidation. In this study, kidney samples taken from healthy human adults and biopsy specimens from patients undergoing rejection following kidney transplantation were analysed and studied. By conducting a single-cell RNA analysis, the type and status of monocyte/macrophages in kidney transplantation were described, in which monocyte/macrophages were observed to form two different subpopulations: resident and infiltrating monocyte/macrophages. Furthermore, previously defined genes were mapped to all monocyte/macrophage types in the kidney and enriched the differential genes of the two main subpopulations using gene expression databases. Considering that various cases of rejection may be of the monocyte/macrophage type, the present data may serve as a reference for studies regarding immune tolerance following kidney transplantation.

Identification of a Novel ACTN4 Gene Mutation Which Is Resistant to Primary Nephrotic Syndrome Therapy.

ACTN4, a gene which codes for the protein α-actinin-4, is critical for the maintenance of the renal filtration barrier. It is well known that ACTN4 mutations can lead to kidney dysfunction, such as familial focal segmental glomerulosclerosis (FSGS), a common cause of primary nephrotic syndrome (PNS). To elucidate whether other mutations of ACTN4 exist in PNS patients, we sequenced the ACTN4 gene in biopsies collected from 155 young PNS patients (≤16 years old). The patients were classified into five groups: FSGS, minimal change nephropathy, IgA nephropathy, membranous nephropathy, and those without renal puncture. Ninety-eight healthy people served as controls. Samples were subjected to Illumina's next generation sequencing protocols using FastTarget target gene capture method. We identified 5 ACTN4 mutations which occurred only in PNS patients: c.1516G > A (p.G506S) on exon 13 identified in two PNS patients, one with minimal change nephropathy and another without renal puncture; c.1442 + 10G > A at the splice site in a minimal change nephropathy patient; c.2191-4G > A at the cleavage site, identified from two FSGS patients; and c.1649A > G (p.D550G) on exon 14 together with c.2191-4G > A at the cleavage sites, identified from two FSGS patients. Among these, c.1649A > G (p.D550G) is a novel ACTN4 mutation. Patients bearing the last two mutations exhibited resistance to clinical therapies.

Effects of long noncoding RNA SPRY4-IT1-mediated EZH2 on the invasion and migration of lung adenocarcinoma.

We aim to investigate the interaction between the EZH2 and the long noncoding RNA (lncRNA) SPRY4-IT1. We also explore their respective effects on human lung adenocarcinoma (LA) cell invasion and migration. Both LA and adjacent normal tissues were obtained from 256 LA patients. SPTY4-IT expression and EZH2 mRNA expressions in tissues and cells were detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR). The siRNAs against SPRY4-IT1 and EZH2 were co-transfected into A549 and H1975 cells. The interaction between SPRY4-IT1 and EZH2 was determined using a RNA pull-down assay and a RNA immunoprecipitation (RIP) assay. A Transwell assay and scratch assay were used to evaluate the cell migration and invasion abilities. The expressions of E-cadherin and Vimentin in the epithelial-mesenchymal transition (EMT) and EZH2 protein expression were detected through western blotting. SPRY4-IT1 expression was observed to be significantly lower, while the expression of EZH2 was higher in the LA tissues than in the adjacent normal tissues. Compared with the HBE cell line, expressions of SPRY4-IT1 in each human LA cell line had decreased, with the lowest observed reduction in the A549 cell line, while EZH2 mRNA and protein expression increased in each human LA cell lines. After SPRY4-IT1-siRNA was transfected into A549 and H1975 cells, invasion and migration abilities were enhanced, in addition to a reduction in the expression of E-cadherin, while expressions of Vimentin exhibited an increased rate. Consequently, we find that EZH2 promotes LA cell invasion and metastasis by inhibiting SPRY4-IT1 expression.

Inhibition of TRPC6 Signal Pathway Alleviates Podocyte Injury Induced by TGF-ß1.

BACKGROUND/AIMS: Transforming growth factor beta 1 (TGF-ß1) plays a critical role in the pathogenesis of glomerulosclerosis. The purpose of this study was to examine the effects of inhibition of transient receptor potential cation channel C6 (TRPC6) on podocyte injury induced by TGF-ß1 via nephrin and desmin mechanisms. METHODS: A rat model of nephropathy was first induced by intravenous injections of adriamycin to determine TRPC6 signal pathway engaged in glomerulosclerosis in vivo. Conditionally immortalized podocytes were cultured in vitro and they were divided into four groups: control; TGF-ß1 treatment; TGF-ß1 with TRPC6 knockdown and TGF-ß1 without TRPC6 knockdown. Real time RT-PCR and Western blot analysis were employed to determine the mRNA and protein of expression of nephrin, desmin and caspase-9, respectively. Flow cytometry was used to examine the apoptotic rate of podocytes and DAPI fluorescent staining was used to determine apoptotic morphology. RESULTS: In vivo experiment, adriamycin significantly upregulated the protein expression of TGF-ß1, TRPC6, desmin and caspase-9, and decreased nephrin. Consistent with the latter results, in vitro experiment mRNA and protein expression of desmin and caspase-9 was increased in cultured TGF-ß1-treated podocytes, whereas nephrin was declined as compared with the control group. Importantly, TRPC6 knockdown significantly attenuated the upregulated desmin and caspase-9, and alleviated impairment of nephrin induced by TGF-ß1. Moreover, typical morphologic features were presented in apoptotic podocytes. The number of apoptotic podocytes was increased after exposure to TGF-ß1 and this was alleviated after TRPC6 knockdown. TRPC6 knockdown also decreased an apoptosis rate of TGF-ß1-treated podocytes. Note that negative TRPC6 transfection control failed to alter an increase of the apoptosis rate in TGF-ß1-treated podocytes. CONCLUSIONS: TGF-ß1 induced by glomerulosclerosis impairs the protein expression of nephrin and amplifies the protein expression of desmin and caspase -9 via TRPC6 signal pathway. Inhibition of TRPC6 alleviates these changes in podocytes-treated with TGF-ß1 and attenuated apoptosis of podocytes. Our data suggest that TRPC6 signal plays an important role in mediating TGF-ß1-induced podocyte injury via nephrin, desmin and caspase-9. Results of the current study also indicate that blocking TRPC6 signal pathway has a protective effect on podocyte injury. Targeting one or more of these signaling molecules may present new opportunities for treatment and management of podocyte injury observed in glomerulosclerosis.

Activation of TLR5 induces podocyte apoptosis.

The apoptosis plays a critical role in a number of inflammatory disorders. Bacterial infection is one of the causes inducing apoptosis. This study aims to investigate the mechanism by which activation of TLR5 induces podocyte apoptosis. In this study, a podocyte cell line was cultured in RPMI1640 medium. The expression of TLR5 was assessed by real-time PCR and Western blotting. The Fas ligand gene transcription was assessed by immunoprecipitation and chromatin immunoprecipitation assay. The results showed that the expression of TLR5 was observed in the podocytes at both mRNA and protein levels. Exposure to TLR5 ligand, flagellin, induced Fas ligand expression and podocyte apoptosis. p300, one of the histone acetyltransferases, mediated the Fas ligand gene transcription in podocytes. In conclusion, TLR5 activation plays an important role in the induction of podocyte apoptosis.

Apo E gene polymorphism affects development of type 2 diabetic nephropathy in Asian populations, especially in East Asians: an updated meta-analysis.

BACKGROUND: Many studies have determined the correlation between the Apolipoprotein E (APO E) gene polymorphisms and diabetic nephropathy, but their results are inconclusive. MATERIAL/METHODS: With the aim to confirm this correlation, we performed a meta-analysis of 16 studies. The dichotomous data are presented as the odds ratio (OR) with a 95% confidence interval (CI). RESULTS: The results of our study indicate that APO ε2 allele among the pooled Asian populations were more likely to show high risk of DN development (2 allele vs. ε3 allele: pooled OR =1.629, 95% CI=1.010-2.628, P=0.045). For further analysis, the APO e2 allele was associated with progress of DN in the group with duration >10 years, but not in the group with duration <10 years (ε2 allele vs. ε3 allele: pooled OR=1.920, 95% CI=1.338-2.754, P<0.001). The APO e2 polymorphism increased the susceptibility to DN in Asian population compared with healthy people (ε2 allele vs. ε3 allele: pooled OR=1.629, 95% CI=1.010-2.628, P=0.045). CONCLUSIONS: Development of DN is associated with APO E polymorphisms in Asian populations, especially in East Asians.