Objective To investigate the correlation between body composition and cardiovascular disease (CVD) in patients with chronic kidney disease (CKD). Methods CKD patients who were hospitalized in the Department of Nephrology of Chongqing General Hospital from January 2017 to December 2019 and had complete clinical biochemical data were divided into CKD patients with CVD and CKD patients without CVD according to their medical history and corresponding auxiliary examinations. Clinical data were collected and anthropometric measurements were conducted. Skeletal muscle index (SMI), appendage lean mass/height², total body fat (TBF), visceral adipose tissue (VAT), bone mineral capacity, bone mineral density and et al, were measured by dual-energy X-ray absorptiometry. T test, U test and Chi-square test were used for statistical analysis. Logistic regression was used to analyze the relationship between body composition and CVD. Results A total of 604 CKD patients were included in this study, including 560 patients (92.7%) with CKD stage 3, 44 patients (7.3%) with CKD stage 4, and 180 CKD patients with CVD (29.8%), 424 CKD patients without CVD (70.2%). Compared with CKD patients without CVD, the proportion of men, the proportion of hypertension, the proportion of diabetes, age, duration of CKD, systolic blood pressure, blood uric acid, waist to hip ratio and waist circumference were higher (all P<0.05), while low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, and estimated glomerular filtration rate (eGFR) were lower in CKD patients with CVD (all P<0.05). In terms of body composition, SMI (t=-11.964, P<0.001) and body mass index (t=-4.462, P<0.001) in CKD patients with CVD were significantly lower than those in CKD patients without CVD, but VAT (t=3.089, P=0.002) and TBF (t=5.177, P<0.001) in CKD patients with CVD were significantly higher. After adjusting for confounders such as age, CKD duration, hypertension history, diabetes history, LDL-C, body mass index, eGFR, TBF, etc. by multivariate logistic regression analysis, the risk of CKD patients suffering from CVD increased significantly with the decrease of SMI [with SMI high tertile (36.37%-50.80%) as reference, SMI middle tertile (28.23%-36.31%): OR=1.49, 95%CI 1.24-1.71, P=0.003; SMI low tertile (15.28%-28.19%): OR=2.17, 95%CI 1.79-2.62, P<0.001], and VAT was not found to be associated with the risk of CVD in CKD patients (P>0.05). Conclusion Reduction of SMI is independently associated with CVD in CKD patients.

Objective To study the relationship between the expression of carnitine palmitoyltransferase 1α (CPT1α) and progression of renal interstitial fibrosis and chronic kidney disease (CKD), and to evaluate the value of CPT1α as a biomarker in pathological diagnosis of renal interstitial fibrosis and CKD. Methods As a retrospective cohort study, information of CKD patients dignosed with tubulointerstitial fibrosis by renal biopsy and receiving follow-up from March 1, 2010 to July 30, 2017 in the Second Affiliated Hospital of Nanjing Medical University were collected. Renal tissues were stained by immunohistochemistry to detect the expression of CPT1α protein and then divided into three groups according to the quartile of proportion of CPT1α positive staining cells, including group Q1(>67.89%), group Q2(49.84%-67.89%) and group Q3(<49.84%). The degree of renal interstitial fibrosis was measured by Masson staining and lipid deposition was represented by Bodipy staining. Messenger RNA of CPT1α and collagen as well as other extracellular matrix genes were detected by real time-PCR. Relationships between proportion of CPT1α positive staining cells and renal interstitial fibrosis and renal function were analyzed by linear regression analysis. The relationship between CPT1α positive cell number ratio and renal function progression was measured by Pearson correlation analysis and generalized linear model. The effect of lipid-lowering medicine on renal function of CKD patients was analyzed by paired comparative analysis. Results Ninety patients with CKD were included in this study. Renal interstitial fibrosis and lipid droplets deposition area increased in Q2/Q3 group compared with Q1 group by Masson and Bodipy staining (all P<0.05). Messenger RNA level of extracellular matrix-related proteins increased in Q2/Q3 group by real time-PCR than those of Q1 group (all P<0.05). Linear regression analysis showed that fibrosis area was negatively correlated with the proportion of CPT1α positive staining cells (r=-0.309, P<0.01). The baseline expression of CPT1α in renal issues was negatively related with serum creatinine (Scr) (r=-2.801, P<0.001), positively related with estimated glomerular filtration rate (eGFR) (r=1.240, P<0.001). After a medium follow-up of 3.47 years, CPT1α positive cell number ratio was positively correlated with eGFR change rate by Pearson analysis (r=0.220, P=0.038). Paired stratified analysis showed that taking lipid-lowering medicines attenuated the decrease of eGFR in Q2 group and Q3 group but not in Q1 group (both P<0.05). Conclusions The decline of CPT1α in renal tissues of CKD patients is associated with the increase of Scr, the decrease of eGFR and renal interstitial fibrosis. CPT1α is a promising molecular marker to evaluate the degree of renal fibrosis and the progression of CKD.

Objective To understand the comprehensive geriatric assessment (CGA) scores in chronic kidney disease (CKD) patients aged 65 years and older, and analyze the related influencing factors of quality of life. Methods A total of 189 patients who were over 65 years old and diagnosed with CKD in the Department of Nephrology of Shanxi Provincial People's Hospital from October 2016 to October 2019 were included retrospectively. The patients were divided into dialysis group (n=90 cases) and non-dialysis group (n=99 cases) according to whether dialysis or not. The concise CGA scores included age, basic activities of daily living (BADL), instrumental activities of daily living (IADL), and modified cumulative illness rating score for geriatrics (MCIRS-G). Pearson correlation analysis was used to analyze the relationship between different scale scores and clinical indexes. Multiple linear regression analysis was used to further analyze independent related factors of the quality of life in elderly CKD patients. Results Compared with the non-dialysis group, the BADL score and IADL score in the dialysis group were significantly reduced [(70.00±33.28) vs (93.38±14.32), t=6.166, P<0.001；(9.78±7.12) vs (15.95±5.74), t=6.520, P<0.001], while the MCIRS-G score was significantly increased [(31.13±4.00) vs (27.29±5.17), t=-5.741, P<0.001]. Linear regression analysis performed on the data of non-dialysis group patients showed that estimated glomerular filtration rate (eGFR), serum uric acid (SUA), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), blood potassium and chlorine were positively correlated with BADL and IADL scores (all P<0.05). B-type natriuretic peptide (BNP) was negatively correlated with BADL score (P<0.01). BNP and age were negatively correlated with IADL score (both P<0.05). Fasting blood glucose (FBG) was positively correlated with MCIRS-G or MCIRS-G other than kidney (both P<0.05), and eGFR, SUA, total cholesterol, and HDL-C were negatively correlated with MCIRS-G or MCIRS-G other than kidney (all P<0.05). Multiple linear regression analysis showed that eGFR was an independent influencing factor for BADL (P<0.01). Age and eGFR were independent influencing factors for IADL (both P<0.05). Conclusions The decline of quality of life in elderly CKD patients is related with eGFR, SUA, age, BNP and HDL-C levels, and eGFR and age are independent influencing factors.

Objective To investigate the number of necroptotic renal tubular epithelial cells in renal tissues of patients with chronic kidney disease (CKD) and the correlation with clinicopathologic parameters, and explore its role in the progression of the excessive loss of renal tubular cells and chronic kidney injury. Methods Renal tissue samples from 60 patients (18-65 years old) with CKD proven by kidney biopsy in the First Affiliated Hospital of Hainan Medical University from June 2017 to June 2019 were collected. According to internationally accepted K/DOQI guidelines, the patients were divided into 1-4 stages of CKD, with 15 cases in each stage. The number of necroptotic renal tubular epithelial cells in patients with different stages of CKD was detected using receptor-interacting protein 3 (RIP3) and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) fluorescent staining, and the expression of RIP3 and MLKL, marker protein of necroptosis, was detected by immunohistochemistry. Pearson correlation analysis was used to analyze the correlation between the percentage of necroptotic renal tubular epithelial cells and clinicopathologic parameters. In addition, the expression of angiotensinogenⅡ receptor (AT2R) in renal tissue and its correlation with the percentage of necroptotic renal tubular epithelial cells were analyzed. Results With the development of CKD, the structural destruction of renal tubules in patients with CKD was gradually aggravated, and the renal tubules in the corresponding areas were atrophied, accompanied by worsening interstitial fibrosis. The adjacent renal tubules were focally dilated and numerous protein tubules were seen in the tubules. Importantly, renal tubular injury score in second and third stage of CKD was significantly higher than that in control group (both P<0.01). TUNEL+RIP3 immunofluorescence staining results showed that the percentage of TUNEL/RIP3 double positive renal tubular epithelial cells (necroptotic renal tubular epithelial cells) in renal tubules of the second and third stage of CKD was higher (all P<0.01). Immunohistochemical results showed that RIP3, MLKL and AT2R proteins were mainly expressed in cytoplasm of renal tubular epithelial cells, and the expression of RIP3, MLKL and AT2R in renal tubular epithelial cells was higher in the second and third stage of CKD patients (all P<0.05). Pearson correlation analysis showed that the percentage of necroptotic renal tubular epithelial cells was positively correlated with blood urea nitrogen (r=0.514, P=0.003), serum creatinine (r=0.507, P=0.019), serum cystatin C (r=0.571, P=0.026), serum uric acid (r=0.592, P=0.008), renal tubules injury score (r=0.901, P<0.001), renal interstitial fibrosis index (r=0.700, P=0.001) and the expression of AT2R protein in renal tissue (r=0.715，P=0.001). Conclusions As CKD progresses, necroptosis of renal tubular epithelial cells in CKD patients occurs. The necroptotic cell death may be an important factor leading to renal tubular epithelial cell excessive death and the progression of chronic kidney injury. Furthermore, necroptosis of renal tubular epithelial cells may be related to the high expression of AT2R in kidney tissue.

Objective To explore the clinical characteristics of chronic kidney disease (CKD) at the stage 3-5D in children with renal anemia, and provide reference data for standardized diagnosis and treatment. Methods A single-center retrospective study was conducted to collect clinical data in children with CKD at Beijing Children's Hospital Affiliated to Capital Medical University from January 2016 to December 2018. The patients were divided into CKD stage 3 group, stage 4 group and stage 5 group according to estimated glomerular filtration rate. The indexes of anemia among the groups were compared. Data on anemia indicators, treatment, and anemia improvement in maintenance dialysis children at stage 5D were analyzed. Results A total of 171 children with CKD were included in the study. The hemoglobin levels in CKD stage 3 group, stage 4 group and stage 5 group were (126.4±20.5) g/L, (90.8±26.0) g/L and (78.7±18.4) g/L, respectively, and there was a statistical difference among the groups ( χ²=61.982, P<0.001; trend test F=71.061, P<0.001). The incidences of anemia in children with CKD stage 3, stage 4 and stage 5 were 27.3%(9/33), 83.3%(25/30) and 95.4%(105/108), respectively. Mild, moderate and severe anemia in children with CKD stage 3 accounted for 15.2%(5/33), 12.1%(4/33) and 0(0), respectively. Mild, moderate and severe anemia in children with CKD stage 4 accounted for 26.7%(8/30), 50.0%(15/30) and 6.7%(2/30), respectively. Mild, moderate and severe anemia in children with CKD stage 5 accounted for 21.3%(23/108), 60.2%(65/108) and 15.8%(17/108), respectively. Anemia type was mostly normocytic anemia. The hemoglobin of 30 children with CKD stage 5D at the initial stage of dialysis was (79.3±16.3) g/L. Twenty-three children with CKD stage 5D received erythropoietin combined with oral iron or intravenous iron therapy. The hemoglobin compliance rates in children with maintenance dialysis in initial phase, 1 month, 2 months and 3 months were 6.7%(2/30), 16.7%(5/30), 63.3%(19/30) and 90.0%(27/30), respectively. The correction time for anemia was (2.5±1.0) months. Twelve children with CKD stage 5D received iron sucrose infusion, and no adverse reaction occurred. Conclusions Renal anemia has a high incidence in children with CKD. Early and standardized treatment is of great significance to improve outcome of renal anemia. Venous iron infusion is a safe and effective treatment method for children with maintenance dialysis.

Objective To investigate the effects and underlying mechanisms of phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/NF-κB signaling pathway in human kidney-2 (HK-2) cells of hyperuricemic nephropathy. Methods HK-2 cells were cultured in vitro and randomly divided into control group and experimental group. The experimental group was induced by high uric acid (720 μmol/L) immersion for 48 h to establish a cell model of hyperuricemic nephropathy in vitro and subsequently divided into hyperuricemic group, overexpressed protease activated receptor 2 (PAR2) and knockdown PAR2 group. The expressions of PAR2, PI3K, AKT, NF-κB mRNA were measured by real-time PCR. The expressions of PAR2, PI3K, AKT and NF-κB protein were measured by Western blotting. The expressions of tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1 (MCP-1), interleukin-6 (IL-6), pro-interleukin-1β (pro-IL-1β), interleukin-1β (IL-1β) and transforming growth factor-β1 (TGF-β1) were detected by enzyme linked immunosorbent assay (ELISA). Results (1) Compared with the control group, the expressions of PAR2, PI3K, AKT and NF-κB mRNA and protein in hyperuricemic group were significantly increased (all P<0.05), the expressions of TNF-α, MCP-1, IL-6, pro-IL-1β, IL-1β and TGF-β1 in the supernatant in hyperuricemic group were significantly increased (all P<0.01). (2) Compared with the hyperuricemic group, the expressions of PAR2, PI3K, AKT and NF-κB mRNA and protein in overexpressed PAR2 group were significantly increased (all P<0.05), the expressions of TNF-α, MCP-1, IL-6, IL-1β and TGF-β1 in the supernatant were significantly increased (all P<0.05). (3) Compared with the hyperuricemic group, the expression of PAR2, PI3K, AKT and NF-κB mRNA and protein in knockdown PAR2 group were significantly decreased (all P<0.05), the expressions of IL-6, pro-IL-1β, IL-1β and TGF-β1 in the supernatant were significantly decreased (all P<0.05). Conclusions In the process of uric acid-induced HK-2 cell damage, uric acid significantly up-regulates the expression of PI3K/AKT/NF-κB signaling pathway by activating PAR2, leading to a marked increase in inflammatory damage. Knocking down PAR2 inhibits the expression of PI3K/AKT/NF-κB signaling pathway, which can effectively reduce the inflammatory damage of HK-2 cells.