Clinico-pathological features and renal outcomes of primary IgA nephropathy with IgM deposition / 中华肾脏病杂志

Objective To investigate the clinico-pathological features and renal outcomes of primary IgA nephropathy (IgAN) with glomerular IgM deposition.Methods Primary IgAN diagnosed with biopsy from January 2006 to December 2011 were recruited.Patients were divided into groups according to IgM deposition (Group A) and without IgM deposition (Group B).In addition,Group A was subdivided into two groups based on the position of IgM deposits as the mesangium (Group A1) and both mesangium and capillary wall (Group A2).Renal outcomes were defined as end stage renal disease (ESRD) and/or the doubling of baseline serum creatinine.Clinico-pathological features were retrospectively compared.Kaplan-Meier was conducted for renal outcomes,and Cox regression model was used to analyze the prognostic value of IgM deposition and the position of IgM deposition in the progression of nephropathy in IgAN patients.Results 939 patients were enrolled with 422 (44.9％) having IgM deposition (Group A).Of the 422 patients,382 patients were divided as Group A 1,whereas 40 patients were noted as Group A2.Compared to Group B,hemoglobin,serum protein,albumin and serum IgG levels in group A were significantly lower,and the cholesterol and serum IgM levels were significantly higher (all P ＜ 0.05).There was no significant difference in serum creatinine,estimated glomerular filtration rate (eGFR),urinary protein,blood pressure and uric acid between group A and B.In terms of pathological manifestations,patients in Group A exhibited more severe histological lesions including glomerular sclerosis,S1,M1 and interstitial inflammatory cell infiltration (all P＜0.05).Immunofluorescence showed that the proportion of IgG,C1q and Fg deposition in group A was significantly higher than that in group B (all P ＜ 0.05).By Kaplan-Meier,cumulative renal survival rate has no significant difference between Group A and B (Log-rank test x2=0.019,P=0.891).Univariate and muhivariable Cox regression analysis showed that IgM deposition had no significant effect on the renal progression in IgAN patients.Subgroup analysis showed that patients in Group A2 exhibited higher urine protein,creatinine and blood pressure,and lower eGFR and serum albumin,also had worse histological lesions including M1,E1 and T1-2 of Oxford classification (all P＜0.05),Immunofluorescencc showed that the proportion of IgG,C1q and Fg deposition in group A2 was significantly higher than that in group A1 (all P ＜ 0.05).By Kaplan-Meier,renal survival rates calculated from outcomes were lower in Group A2 (Log-rank test x2=1 8.207,P ＜ 0.001).In addition,IgM deposited both in the mesangium and capillary wall was a risk factor for renal progression of IgAN patients with IgM deposition by a univariate Cox hazards regression mode and multivariable-adjusted Cox models (HR=3.621,95％CI 1.924-6.814,P＜ 0.001;HR=2.309,95％CI 1.176-4.533,P=0.015respectively).Conclusions The IgAN patients with IgM deposition relatively had more severe clinicopathological changes,especially those with IgM deposited both in the mesangium and capillary wall.In this study,IgM deposition was not found to be an independent risk factor for the prognosis of kidney in IgAN patients.However,IgM deposited both in the mesangium and capillary wall was an independent risk factor for renal prognosis in IgAN patients with IgM deposition.

Effect of interleukin-1β on activity of vacuolar proton pump and intracellular acidosis in osteoclasts / 中国病理生理杂志

AIM: To study the effect of interleukin-1β (IL-1β) on the activity of vacuolar proton pump (V-ATPase) and intracellular pH value in the osteoclasts for exploring the mechanism of IL-1β to promote osteoclastic bone absorption.METHODS: The mature osteoclasts were attained by induction of bone marrow monocytes/macrophages.The osteoclasts were cultured with α-MEM and treated with different concentrations (0.1, 0.3 and 0.5 μg/L) of IL-1β.After cultured for 48 h, the mRNA and protein expression of V-ATPase was detected.The effect of IL-1β on intracellular pH value, activity of V-ATPase and the bone absorption abilities of osteoclasts were examined.RESULTS: The expression level and activity of V-ATPase were significantly increased and the intracellular pH value of the osteoclasts decreased after incubated with IL-1β for 48 h.Under the same culture condition, the bone absorption capacity of the osteoclasts was promoted.The enhanced bone absorption capability of the osteoclasts was accompanied by an increase in the concentration of IL-1β.CONCLUSION: The mechanism of IL-1β participating in pathological bone absorption in the bone and joint inflammatory diseases is that IL-1β increases the expression and activity of V-ATPase, boosts the production and/or transportation of hydrogen ion, leading to increased osteoclastic bone absorption activity, and resulting in bone destruction.

Tumor necrosis factor alpha enhances the bone-resorptive capabilities of osteoclasts by improving the expression and activity of vocuolar-type ATPase / 中国组织工程研究

BACKGROUND:Vocuolar-type ATPase (V-ATPase) is highly expressed in osteoclasts and especial y plays an important role in osteoclastic bone resorption. Tumor necrosis factor-αis a potent stimulator of bone resorption. However, the effect of tumor necrosis factor-αon expression and activity of V-ATPase is stil not clear. OBJECTIVE:To investigate the mechanism of tumor necrosis factor-αto promote osteoclastic bone resorption by observing expression and activity of V-ATPase. METHODOsteoclasts cultured in vitro were intervened by different concentrations of tumor necrosis factor-α(5, 10, 30μg/L) in order to observe the changes in expression and enzyme activity of V-ATPase and its effects on bone resorption of osteoclasts. Under an inverted microscope, we observed the formation of resorption lacunas, and bone resorption area was analyzed using Image J software. RESULTS AND CONCLUSION:The expression and activity of V-ATPase increased significantly after 48 hours of tumor necrosis factor-αintervention and the increase of tumor necrosis factor-αconcentration might enhance this effect. In addition, osteoclastic bone resorption was promoted after intervention with tumor necrosis factor-α. The bone-resorbing capabilities of osteoclasts increased in paral el with the concentration of tumor necrosis factor-α.The results suggested that tumor necrosis factor-α, as a significant inflammatory mediator involved in the pathological process of bone resorption, not only promotes formation of osteoclasts but also enhances bone-resorbing capabilities of osteoclasts by increasing V-ATPase expression and activity.

Expression and significance of NGAL in MRL/lpr lupus-prone mice / 中华风湿病学杂志

Objective To explore the expression and significance of neutrophil gelatinase-associated lipocalin (NGAL) in lupus nephritis (LN) in mice. Methods Female MRL/lpr lupus mice (n=36) were randomly divided into the experimental group and intervention group, and female Kunming mice (n =18) served as controls. Each mice in the intervention group received intraperitoneal injection of 20 μg anti-mice interleukin (IL)-17 antibody. The serum concentrations of NGAL, IL-17,matrix metalloproteinase(MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 were measured by enzyme-linked immunosorbent assay (ELISA). And the protein expressions of NGAL, IL-17, MMP-9 and TIMP-1 in renal tissue were detected by immunohistochemisty. One-factor analysis of variance (ANOVA) or nonparametric rank sum test was used for the comparisons between the three groups. Associations between these factors were analyzed by Pearson′s test. Results The levels of serum NGAL, IL-17, MMP-9 and TIMP-1 in the experimental group were obviously increased as compared to those in the control group and intervention group [NGAL: (30.31±1.22) ng/ml vs (11.36±0.14) ng/ml, (20.09±0.35) ng/ml, F=986.524, P and the serum levels of IL-17, MMP-9 and MMP-9/TIMP-1(r=0.899, 0.789, 0.925, P<0.01). The protein expression of NGAL in renal tissue was positively correlated with IL-17, MMP-9 and MMP-9/TIMP-1 levels (r=0.929, 0.899, 0.723, P<0.01). Conclusion The level of NGAL in the serum and renal tissue is signifi-cantly increased in the MRL/lpr lupus mice. And it is closely correlated with the levels of IL-17 and MMP-9. Our results suggest the potential role of NGAL in the inflammation of lupus nephritis.

The relationship between IgA nephropathy and low molecular weight urinary protein / 重庆医学

Objective To investigate the relationship among urinary protein molecular weight of IgA nephropathy ,renal tubu‐lointerstitium damage and clinical index ,and discuss the role of low molecular weight urinary protein in the mechanism of IgA pro‐gression .Methods A total of 34 patients with biopsy proven IgAN were studied .We detect the molecular weight of urinary protein by SDS‐PAGE .Data were processed with the classes of tubulointerstitial lesions and laboratory tests such as 24h urinary protein quantitation and serum creatinine(Scr) .Results The urinary protein were divided into four types according the SDS‐PAGE:the ball urinary protein group ,physiologic urinary protein group ,23 × 103 proteinuria group and 10 × 103 proteinuria group .Scores of tubu‐lointerstitial lesions ,twenty four hour urine protein quantitation and Scr level were all significantly higher in 10 × 103 proteinuria group than 23 × 103 proteinuria group (P<0 .05) .Conclusion 10 × 103 proteinuria may have close relationship with the progression of IgAN ,and it may be a useful index for the degree of tubulointerstitial lesions of IgAN .

Receptor activator of nuclear factor kappa-B ligand induces osteoclast precursor culture and differentiation / 中国组织工程研究

BACKGROUND:Previous studies have applied long-bone mechanical separation method to obtain osteoclasts, which are terminal y differentiated cells and cannot further proliferate. Therefore a large number of osteoclasts can be harvested with bone marrow cells inducing culture method and RAW264.7 cells inducing culture method to meet clinical requirements. OBJECTIVE:To investigate the optimal method of receptor activator of nuclear factor kappa-B ligand (RANKL) induced osteoclast precursors to differentiate into mature osteoclasts. METHODS:After bone marrow cells were isolated from mouse, RANKL and macrophage colony stimulating factor were added into the medium together, or RAW264.7 cells were cultured with RANKL to induce osteoclasts. The osteoclast precursors were treated with different concentrations of RANKL to observe the number of generated osteoclasts and evaluate the dose-effect relationship between RANKL and osteoclastogenesis. Annexin V-FITC and propidium iodide staining were used for flow cytometry to analyze the mononuclear-macrophage apoptosis during osteoclastogenesis. RESULTS AND CONCLUSION:When 10μg/L RANKL was used, the peak of osteoclastogenesis appeared at days 6-7;when the concentration of RANKL was up to 100μg/L, the peak appeared at days 4-5. The number of new osteoclasts was dose-dependent on the RANKL concentration. 50μg/L of RANKL was the turning point in the fitted curve from osteoclastogenesis and RANKL concentration. After the RANKL concentration was more than 150μg/L, the number of osteoclasts slowed down obviously. RANKL can induce monocyte-macrophage to form osteoclasts and promote monocyte-macrophage apoptosis. The highest number of osteoclasts would be obtained to each unit of RANKL when monocyte-macrophage cells were cultured with 30μg/L of RANKL in the same vaccination density (104/cm2). Experimental findings indicate that, RAW264.7 cells or bone marrow cells inducing culture methods are simple and feasible, the optimum cellseeding density was 104/cm2;the appropriate stimulation concentration of RANKL was 30-50μg/L.