Objective To observe the mitochondrial damage associated with protein-energy wasting of skeletal muscle in diabetic kidney disease (DKD) model of Goto-Kakizaki(GK) rats and evaluate the effects of low-protein diet supplemented with α-keto acids on muscle wasting.Methods Forty-five male 24-week-age GK rats were randomly divided into three groups,normal protein diet group (NPD),low-protein diet group (LPD) and LPD +or-keto group (Keto).Fifteen gender and age matched Wistar rats were served as control group (CTL).The living condition of GK rats was observed and the weight was measured once a week.Urine albumin,serum glucose,creatinine and urea nitrogen were measured at 24,32,40,48 week age.Soleus muscle was observed to calculate the muscle size and the percentage of Ⅰ and Ⅱ type muscle fiber with software after SDH and NADH staining at 48-week-age.Tissue ultrastructure was observed under the transmission electron microscopy.The activity of citrate synthase was detected by spectrophotometer.Expression of mitochondrial DNA was examined by Q-PCR.Results Compared with the CTL group,NPD,LPD and Keto groups had lower body weight,higher urine albumin,higher serum creatinine and urea nitrogen (P ＜ 0.05).The crosssectional area of muscle fibers was larger in CTL group.Compared with CTL group,the muscle fiber was partly broken,the mitochondrial morphology was obviously changed,the percentage of type Ⅱmuscle fiber was increased significantly (P ＜ 0.05),and the activity of citrate synthase and the number of mitochondrial DNA were decreased significantly in NPD,LPD and Keto groups (P ＜ 0.05).In Keto group,muscle wasting was improved compared with NPD and LPD group (P ＜ 0.05),the crosssectional area of soleus muscle increased and the percentage of type Ⅱ muscle fiber decreased,levels of urine albumin,semm creatinine and urea nitrogen decreased (P ＜ 0.05).Under transmission electron microscopy,the muscle fiber of keto group was intact and mitochondiral morphology was close to that of CTL group.The activity of citrate synthase and number of mitochondiral DNA were higher as compared to CTL group (P ＜ 0.05).There were no significant differences between NPD and LPD group.Conclusions In DKD condition,protein degradation in the skeletal muscle is accelerated,mitochondrion is swelling,the number of mitochondrial DNA is decreased and mitochondrial function is impaired.Low-protein diet supplemented with α-keto acids can improve mitochondrial damage and muscle wasting induced by DKD.

Objective To observe the change of insulin-like growth factor 1 (IGF-1)before and after glucocorticoid (GC) therapy and to explore the effect of its change on bone metabolism in primary nephrotic syndrome (PNS) patients.Methods A total of 39 PNS patients with mean age of (36.73±12.15) years received GC therapy were selected from January 2008 to August 2009 in our hospital.Serum IGF-1,albumin,calcium,phosphorus,parathormone (PTH),25hydroxy vitamin D3,bone gla protein (BGP),degradation products of C-terminal telopeptides of type I collagen (CTx),24-hour urinary protein excretion and the ratio of urinary calcium to creatinine were measured at five time points-before GC therapy,4 weeks,8 weeks,12 weeks and 24 weeks after the use of GC.BMD was also detected at the same time points.Correlations among indexes were analyzed by Pearson.Results Thirty-six PNS patients fulfilled the follow-up and had complete clinical data,while other 3 patients lost.After GC treatment,serum calcium and 25hydroxy vitamin D3 were significantly increased in a time-dependent manner and were negatively correlated with 24-hour urinary protein excretion (r=-0.749,r=-0.831,P＜0.05,respectively).Serum BGP and IGF-1 were decreased after GC therapy in a time-dependent manner while CTx was significantly increased until week 12 after treatment (P＜0.05).Compared with pre-treatment,BMD of various parts had no significant difference at week 4; BMD of lumbar spine (L1-L4) was significantly decreased until week 8 (P＜0.05); BMD of femoral neck and femoral shaft was significantly decreased at week 24 (P＜0.05).IGF-1 was positively correlated with BGP and BMD (r=0.896,r=0.495,P＜0.05) and negatively correlated with serum CTx (r=-0.697,P＜0.05 ).Conclusions Serum IGF-1 level decreases in a time-dependent manner after GC treatment,which is correlated to BGP,CTx and BMD.Glucocorticoid treatment affects bone metabolism through IGF1 pathway possably in patients with PNS.IGF-1 may be used as a new bone biochemical marker of glucocoritcoid - induced osteoporosis.

Objective To study the association of bone metabolism with the degree of proteinuria in patients of chronic kidney diseases (CKD). Methods A total of 71 CKD patients diagnosed as primary glomerulopathy were randomly selected from 2008.1-2009.5 in the First People's Hospital of Shanghai. They were classified into three groups according to proteinuria:group A of 25 patients, proteinuria ＜1.0 g/24 h; group B of 16 patients, proteinuria 1.0-＜3.5 g/24 h;group C of 30 patients, proteinuria ≥ 3.5 g/24 h. Fifty-eight healthy persons were selected from our medical examination center at the same time as control. Serum albumin, calcium, phosphorus,PTH, 25 hydroxy vitamin D3, bone gla protein (BGP), degradation products of C-terminal telopeptides of type I collagen (CTx), 24-h urinary protein excretion, and the ratio of urinary calcium to creatinine (UCa/Cr) were measured. Bone mineral density (BMD) was detected by dualenergy X-ray absorptiometry. Results Compared with control group, serum levels of calcium [(2.23±0.08), (2.13±0.09), (2.04±0.06)vs (2.37±0.12)mmol/L], 25-(OH)D3 [(50.19±6.58), (47.78±6.69), (42.42±10.85) vs (56.34±8.34) nmol/L] were significantly lower and UCa/Cr was significantly higher in A, B, C groups respectively (all P＜0.05). In group B and C, BGP was lower [(18.69±7.35), (16.13±5.76) vs (22.88±6.21) μg/L] and CTx was higher [(413.59±114.93),(516.21±314.25) vs (304.53±234.15) ng/L] (all P＜0.05). BMD was lower only in group C [(1.028±0.090) vs (1.090±0.062) g/cm2, P＜0.05]. Pearson analysis showed that 24-h urinary protein excretion was negatively correlated with serum calcium and 25 hydroxy vitamin D3, and positively correlated with UCa/Cr. UCa/Cr was positively correlated with serum CTx and negatively correlated with BGP. 25-(OH) D3 was positively correlated with BGP and negatively correlated with CTx. Conclusion Bone metabolism disorder exists in CKD patients, presenting the decrease of bone formation and the increase of bone resorption, which is associated with as the degree of proteinuria, especially in patients with nephrotic syndrome.

Objective To study the change of serum insulin-like growth factor 1(IGF-1)in primary nephrotic syndrome(PNS)patients and its relationship with bone metabolism, and to investigate the clinical significance of IGF-1 in the mechanism of bone metabolic disorders in PNS patients. Methods A total of 30 PNS patients with chronic kidney disease(CKD)stage 1 and 2 were randomly selected from 2008.1 to 2009.5 in our hospital. Serum IGF-1, albumin, calcium, phosphorus, PTH,25 hydroxy vitamin D3, bone gla protein(BGP), degradation products of C-terminal telopeptides of type I collagen(CTx), 24-hour urinary protein excretion, and ratio of urinary calcium to creatinine(UCa/Cr)were measured. Healthy control group of 61 persons were randomly selected from our medical examination center at the same time. Results Serum levels of calcium, 25 hydroxy vitamin D3 and BGP were significantly lower;CTx and UCa/Cr were significantly higher in PNS patients(P<0.05)as compared to healthy control group. BMD of PNS patients was lower but without significant difference compared with healthy control group[(1.078± 0.090)g/cm2 vs(1.090±0.062)g/cm2, P>0.05]. Serum level of IGF-1 was significantly lower in PNS patients and was positively correlated with BMD and BGP,and negatively correlated with 24-hour urinary protein excretion and CTx. Conclusions Bone metabolic disorder exists in PNS patients with the appearance of decreased bone formation and increased bone absorption.Serum level of IGF-1 has good correlations with bone biochemical markers.which may be used as a new bone biochemical marker of bone metabolism in kidney disease.

Objective To identity whether there is muscle atrophy phenomenon in end-stage kidney disease patients and to detect the level of transcription factor Foxo1 and the activity of ubiquitin-proteasome system.Methods Twenty-two patients in chronic kidney disease (CKD) stage 5 were selected and their mean muscle cross sectional area was measured.mRNA and protein levels of Foxo1,Atrogin-1,MuRF1 in rectus abdominis biopsies obtained from consecutive patients were detected.Control biopsies were obtained from 8 healthy subjects during elective surgery for abdominal wall hernias and 6 subjects during elective surgery for adenomyosis.Results Compared with the control group,cross sectional area of muscle fibers decreased and the transcription and protein levels of Foxo1,Atrogin-1,MuRF1 were upregulated in CKD group(P＜0.05).Protein level of p-Foxo1 decreased in CKD group(P＜0.05).Conclusion There exist muscle atrophy phenomenon in CKD patients,which may associate with the upregulation of Foxo1 and activation of ubiquitin-proteasome system.

Background and purpose:The association between metabolic syndrome (MS) and renal cell carcinoma (RCC) is still unknown. The aim of this study was to elucidate how MS correlates with the prevalence and malignancy of RCC.Methods:This study enrolled 398 RCC patients (350 clear cell RCC patients, 5 XP11.2 transloca-tion RCC patients, 16 papillary RCC patients and 27 chromophobe RCC patients), 160 normal persons, and 32 benign renal tumor patients. The metabolic status of the patients was assessed, and the link between MS and the prevalence or malignancy of RCC was calculated.Results:Clear cell RCC patients had signiifcantly higher rates of hypertension, higher body mass index (BMI) and longer waist circumference. Forty-eight percent clear cell RCC patients had MS, while the number was 33% for papillary RCC, 26% for chromophobe RCC, 0% for XP11.2, 17% for AML, and 25%for normal people. MS patients had signiifcant higher rates of having clear cell RCC than no-MS patients, however this kind of difference was not seen in other types of RCC. Clear cell RCC patients with higher Furhman grade had lower rates of MS.Conclusion:Patients with MS are more likely to develop clear cell RCC. Patients with high Furhman grade tumors have low MS rates, indicating that high grade tumor may have other originating mechanisms other than metabolic disorders.

Objective To study skeletal muscle atrophy and the change of autophagy in skeletal muscle of patients with chronic kidney disease.Methods Mean muscle cross sectional area,mRNA and protein expression of autophagy markers Bcl-2-adenovirus E1B interacting protein 3 (LC3B),Bcl-2-adenovirus E1B interacting protein 3 (Bnip3),Beclin-1 were measured in rectus abdominis biopsies obtained from 22 consecutive patients with stage 5 CKD scheduled for peritoneal dialysis from 4 hospitals in Shanghai.Control biopsies were obtained from another 8 healthy subjects during elective surgery for adenomyosis and 6 subjects during elective surgery for abdominal wall hernias.Rectus abdominis muscles were obtained at the beginning of surgery.HE staining was performed and mean cross sectional area (CSA) was calculated.Electron microscopy was used to confirm the changes of autophagy.mRNA levels of LC3B,Beclin-1,Bnip3 were evaluated by RT-PCR and protein levels of those parameters were evaluated by Western blotting.Results Compared with control group,mean CSA of muscle fibers was decreased and the transcript levels of LC3B,Beclin-1,Bnip3 were up-regulated in CKD group.Similarly,protein levels of LC3BⅠ,LC3B Ⅱ,Beclin-1 and Bnip3 were increased in CKD group.Additionally,activation of autophagy was confirmed by the appearance of autophagosomes by electron microscopy.Conclusion Chronic kidney disease may cause skeletal muscle atrophy and lead to activation of autophagy,which may contribute to muscle atrophy.

Objective To observe the muscle wasting in diabetic kidney disease (DKD) model of type 2 and non-obese diabetes mellitus in Goto-Kakizaki (GK) rats,and to evaluate the effect of lowprotein diet supplemented with α-keto acids on muscle wasting.Methods Forty-five male 24-weekage GK rats were randomly divided into three groups:normal protein diet group (22％ casein diet,NPD),low protein diet group (6％ casein diet,LPD) and LPD + α-keto group (5％ casein + 1％ α-keto,Keto).Fifteen gender-and age-matched Wistar rats were served as the control group (CTL).The living condition of GK rats was observed and body weight was measured once a week.Urine albumin,serum glucose,lipids,albumin,creatinine and urea nitrogen were measured at the age of 24,32,40,48 weeks.Soleus muscle at the age of 48-week was observed to calculate the muscle size with software.Expressions of atrogin-1,MuRF-1 and MyoD,myogenin were examined by Q-PCR and Western blotting.Results Compared with the CTL group,NPD,LPD,Keto groups had lower body weight [(317.90± 13.81),(330.38±11.96),(390.44±12.25) g vs (429.43± 16.85) g,all P ＜ 0.05],higher urine albumin [(14.36±5.52),(8.12±4.61),(5.58±3.50) mg/24 h vs (0.61±0.16) mg/24 h,all P ＜ 0.05],higher serum creatinine [(81.50±7.88),(66.32±8.36),(63.44±8.21) μmol/L vs (24.43±6.15) μmol/L,all P ＜0.05] and urea nitrogen [(7.53±1.05),(5.63±1.40),(5.54±0.97) mmol/L vs (2.98±0.62) mmol/L,all P ＜0.05].The cross-sectional area of soleus muscle fibers was larger in CTL group.Compared with CTL group,the expression levels of atrogin-1 and MuRF-1 increased significantly (all P ＜ 0.05),and of MyoD and myogenin decreased significantly in NPD,LPD,Keto groups (all P ＜ 0.05).In Keto group after 40 weeks,muscle wasting was improved compared with NPD and LPD group [body weight (381.62± 15.82) g vs (331.50±17.58),(326.60± 13.43) g,all P ＜ 0.05],cross-sectional area of soleus muscle increased,levels of urine albumin,serum creatinine and urea nitrogen decreased (all P ＜ 0.05),the protein expressions of atrogin-1 and MuRF-1 decreased,and myogenin and MyoD were higher as compared to CTL group (all P ＜ 0.05).There were no significant differences between NPD and LPD group.Conclusions In DKD condition,protein degradation in the skeletal muscle is accelerated,the genes which control muscle atrophy are activated,and proliferation and differentiation of the muscle satellite cells are impaired.Low-protein diet supplemented with α-keto acids can improve muscle wasting induced by DKD.

Social network analysis has been a study hot spot in academic circle in recent years and is applied in several fields.After a brief description of its basic theories and study methods, its application in domestic medical and health field were analyzed with its key study hot spots summarized and its problems pointed out, in order to provide the methods that can learned in domestic medical and health studies.

Objective To investigate the expression of Notch 1 receptor in renal tissues of patients with hepatitis B virus associated-glomerulonephritis (HBV-GN) and its role in the pathogenesis of HBV-GN.Methods A total of 48 patients with HBV-GN confirmed by renal biopsy during 2008-2010 were enrolled in the study.Distribution of Notch1 receptor in renal tissue of HBV-GN was detected by immunohistochemistry and the association between the distribution of Notch1 receptor and HBsAg was examined by double-label immunofluorescence assays.Correlations of Notch1 receptor expression with renal pathology and clinical parameters of HBV-GN were analyzed.Results Notch1 receptor distributed mainly in renal tubular epithelial cells and interstitial area as brownish red granules,and a few expression in glomerulus was also found.The positive score of Notch1 receptor expression in HBV-GN patients was significantly higher as compared to primary glomerulonephritis patients with serum HBsAg positive or negative and normal renal tissue controls.Notch1 receptor expression was more obvious in membrano-proliferative glomerulonephritis (MPGN) and mesangial proliferative nephritis (MsPGN) patients,but there was no significant difference among the different pathology groups.Distribution of Notch1 receptor was consistent with the distribution of HBsAg and its intensity was positively correlated with renal interstitial fibrosis (r=0.473,P=0.001),tubular atrophy (r=0.690,P=0.000),inflammatory cell infiltration (r=0.616,P=0.000).Negative correlation was found between renal function and the intensity of Notch1 receptor (r=-0.393,P=0.006).Conclusions Notch1 receptor expression increases in the renal tissues of HBV-GN patients and distributes mainly in renal tubular epithelial cells and interstitium,which is consistent with the distribution of HBsAg.Its intensity is closely correlated with renal interstitial lesions and renal function.Abnormal expression of Notchl receptor in renal tissue of HBV-GN may be involved in the progress of HBV-GN.