Shuanghong Mo

Role of PAX2 gene polymorphisms in Henoch-Schonlein purpura nephritis.

Objective:  To investigate the distribution of polymorphisms in the PAX2 gene in children with Henoch–Schonlein purpura with and without nephritis (HSPN and HSP, respectively), with particular attention to the relationship between PAX2 gene polymorphisms and the development of kidney pathology.

Effect of Stem Cell Factor and Granulocyte-Macrophage Colony-Stimulating Factor-Induced Bone Marrow Stem Cell Mobilization on Recovery from Acute Tubular Necrosis in Rats

Background: Acute tubular necrosis (ATN) is the most common reason for acute kidney injury (AKI), and there is still an absence of effective therapies. Objective: To assess the value of bone marrow cell mobilization by stem cell factor (SCF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) therapy in rats with gentamicin-induced ATN. Methods: ATN was induced in male Sprague–Dawley (SD) rats with five daily high-dose intraperitoneal injections of gentamicin. Subcutaneous injections of SCF and GM-CSF were administered simultaneously and these cytokines were observed on days 2, 5, 10, 17, 24, and 31. Peripheral blood and renal tissue CD34+ cell count, mortality rate, blood urea nitrogen (BUN), serum creatinine (SCr), creatinine clearance rate (CCr), and histopathologic lesion scores were determined. Twelve hours after bone marrow ablation (BMA) by lethal X-ray radiation, specific pathogen-free (SPF) ATN rats were given five daily injections of SCF and GM-CSF. BUN, SCr, and histopathologic lesion scores were evaluated on days 2, 5, and 10. Results: Peripheral blood CD34+ cell count increased significantly in ATN rats between 2 and 10 days after SCF and GM-CSF injection. Mortality was reduced from 34.7% in the ATN group to 18.6% in the ATN+CSF. In addition, cytokines administration significantly decreased SCr and BUN. Moreover, cytokines rapidly ameliorated tubular injury. There was no significant effect on ATN rats after BMA. Conclusions: This study demonstrated that SCF and GM-CSF effectively mobilized bone marrow cells in ATN rats, and cytokines administration partially prevented gentamicin-induced ATN. These results suggest that bone marrow stem cell (BMSC) mobilization may be an effective therapy for ATN.

Nephroprotective effects of subcapsular transplantation of metanephric mesenchymal cells on gentamicin-induced acute tubular necrosis in rats

BackgroundThe subcapsular transplantation of metanephric mesenchymal cells (MMCs) may be a new therapeutic approach for the treatment of acute tubular necrosis (ATN). To investigate this hypothesis and provide evidence for its possible use in the clinic, we evaluated the nephroprotective effects of transplanting MMCs into the renal subcaspsule of rats with ATN induced by gentamicin.MethodsMMCs were expanded in culture. After gentamicin-induced ATN was established, fluorescently-labeled cells were transplanted and traced in kidney tissues by fluorescence microscopy. Serum creatinine (Cr), urea nitrogen (BUN), and N-acetyl-b-D-glucosaminidase (NAG) levels were determined at different time points. Kidney pathology was studied by hematoxylin-eosin staining. Apoptosis was examined by the TUNEL assay.ResultsIn the MMCs-treated group, the mortality rate decreased; BUN, Cr, and NAG levels peaked at 8 days, and were significantly lower than those in the other groups at 11 and 14 days. RIMM-18 cells locally recruited through precise tropism to sites of injury had the ability to migrate into the tubuli from the renal subcapsule. Damage to the cell-treated kidneys was reduced. The pathologic lesion scores of tubular damage reached the highest values at 8 days in the treated kidneys and 11 days in the untreated ones. The apoptotic index showed that the peaks of apoptosis occurred at earlier stages of the injury process in cell-treated than in untreated kidney and thereafter declined in a time-dependent manner.ConclusionThe subcapsular transplantation of MMCs could ameliorate renal function and repair kidney injury.

Differences in Tissue Expression of HBV Markers in Children with HBV-Associated Glomerulonephritis

Abstract Background/Aims: Hepatitis B virus-associated glomerulonephritis (HBV-GN) is recognized as one of the major secondary nephropathies in HBV high-risk areas. To determine possible differences in the expression of HBV immune markers in tissues, we retrospectively examined HBV immune markers in the serum, renal tissues, and liver tissues in 132 HBV-GN children. Methods: All 132 patients had biopsy-proven HBV-GN including the presence of positive HBV antigens in the kidney. Serum-HBV immune markers were tested by an enzyme-linked immunosorbent assay. Renal and liver biopsies were done in 26 patients. All renal tissues were examined for HBV immune markers by immunofluorescence, and liver tissues were examined by immunohistochemistry. Results: Among the 132 patients, all showed varying degrees of kidney injury. Serum hepatitis B envelope antigen (HBeAg) was positive in 80 patients and negative in 52 patients. The positivity rate of Hepatitis B core antigen in renal tissue was statistically higher in serum HBeAg (−) than in serum HBeAg (+) patients (96.2% vs. 55.0%). Furthermore, there was no relationship between the presence of hepatitis B surface antigen and HBcAg in liver and renal tissue. Conclusion: HBV markers are not consistently present in serum, renal tissues, and liver tissues in children with HBV-GN.

Genetic mutational testing of Chinese children with familial hematuria with biopsy‑proven FSGS

Focal segmental glomerulosclerosis (FSGS) is a pathological lesion rather than a disease, with a diverse etiology. FSGS may result from genetic and non-genetic factors. FSGS is considered a podocyte disease due to the fact that in the majority of patients with proven-FSGS, the lesion results from defects in the podocyte structure or function. However, FSGS does not result exclusively from podocyte-associated genes, however also from other genes including collagen IV-associated genes. Patients who carry the collagen type IVA3 chain (COL4A3) or COL4A4 mutations usually exhibit Alport Syndrome (AS), thin basement membrane neuropathy or familial hematuria (FH). Previous studies revealed that long-time persistent microscopic hematuria may lead to FSGS. A case of a family is presented here where affected individuals exhibited FH with FSGS-proven, or chronic kidney disease. Renal biopsies were unhelpful and failed to demonstrate glomerular or basement membrane defects consistent with an inherited glomerulopathy, and therefore a possible underlying genetic cause for a unifying diagnosis was pursued. Genomic DNA of the siblings affected by FH with biopsy-proven FSGS was analyzed, and their father was screened for 18 gene mutations associated with FSGS [nephrin, podocin, CD2 associated protein, phospholipase C ε, actinin α 4, transient receptor potential cation channel subfamily C member 6, inverted formin, FH2 and WH2 domain containing, Wilms tumor 1, LIM homeobox transcription factor 1 β, laminin subunit β 2, laminin subunit β 3, galactosida α, integrin subunit β 4, scavenger receptor class B member 2, coenzyme Q2, decaprenyl diphosphate synthase subunit 2, mitochondrially encoded tRNA leucine 1 (UUA/G; TRNL1) and SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily a like 1] using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry technology. Then whole exome sequencing (WES) was performed in the two probands to ascertain whether there were other known or unknown gene mutations that segregated with the disease. Using mass array technology, a TRNL1 missense homozygous mutation (m. 3290T>C) was identified in the probands diagnosed with FH and manifested as FSGS on biopsy. In addition, a COL4A4 missense mutation c. 4195A>T (p. M1399L) in heterozygous pattern was identified using WES. None of these variants were detected in their father. In the present study, a mutation in TRNL1 (m. 3290T>C) was identified, which was the first reported variant associated with FSGS. The COL4A4 (c. 4195A>T) may co-segregate with FSGS. Screening for COL4A mutations in familial FSGS patients is suggested in the present study. Genetic investigations of families with similar clinical phenotypes should be a priority for nephrologists. The combination of mass array technology and WES may improve the detection rate of genetic mutation with a high level of accuracy.

Distribution of infused umbilical cord mesenchymal stem cells in a rat model of renal interstitial fibrosis

Abstract Aims: Stem cell transplantation for the treatment of kidney diseases is dependent on choice of transplant pathway. We evaluated the safety of human umbilical cord mesenchymal stem cells through peripheral infusion and their distribution in a rat model of renal interstitial fibrosis (RIF). Method: Cryopreserved umbilical cord mesenchymal stem cells were infused via tail vein injection into rats with unilateral ureteral obstruction and Sham-operated. Blood, kidney, heart, liver, spleen and lung were collected at 14, 21, and 28 days after infusion. Testing included microscopic observation of kidney morphological changes and immunohistochemical testing to identify and count the number of MAB1281 (labeled human cells) positive cells in the heart, liver, spleen, lungs, and kidneys of different treatment groups. Results: There was no significant difference in the Sham-operated group and Sham-operated + cell transplantation group at different time points. Human cells were identified mainly in the lungs, spleen, and kidney. The number of human umbilical cord mesenchymal stem cells in the kidney was greater in the unilateral ureteral obstruction + cell transplantation group, compared to the Sham-operated + cell transplantation group. human umbilical cord mesenchymal stem cells were mainly located in the interstitium of the left kidney. These results suggest that infused mesenchymal stem cells were primed to engraft a damaged kidney, especially damaged renal interstitium. Conclusions: Intravenous infusion of exogenous umbilical cord mesenchymal stem cells is feasible and safe. Infused mesenchymal stem cells can reach damaged kidney tissues with obstructive RIF after a vein graft.

Podocalyxin expression in renal tissues and correlation with the number of urinary podocytes in children with Henoch-Schonlein purpura nephritis.

OBJECTIVE To analyze the podocalyxin (PCX) expression in the kidney and the number of urinary podocytes in different pathological grades of Henoch-Schonlein purpura nephritis (HSPN), and to determine whether the number of urinary podocytes reflects the renal damage in HSPN. METHODS Fifty-six children diagnosed with HSPN in our hospital were enrolled in the study and classified into 4 groups by renal pathology: grade II (IIa+IIb) (n=10), grade III (IIIa+IIIb) (n=21), grade IV (n=16), and grade V (n=9). Four kidney autopsy specimens without histomorphologic lesions and 8 urine samples from healthy children served as controls. With immunofluorescence assay, the PCX expression in 4 normal renal tissues and in the renal tissues of the 56 HSPN children was detected and quantitatively analyzed. Positive rate and the number of urinary podocytes were detected in the 8 healthy children and 56 HSPN children. RESULTS In the renal tissues of the normal control group and grade II (IIa+IIb) HSPN group, the PCX expression was complete. The percentage of the PCX positive area out of the total glomerular area in the renal tissues of 2 groups had no significant difference (P>0.05). In the renal tissues of grade III (IIIa+IIIb), IV, and V HSPN groups, the PCX expression showed various degrees of loss, decreasing in turn from grade II (IIa+IIb), III (IIIa+IIIb), IV to V, with significant differences between each group (P<0.01). For HSPN with grade III (IIIa+IIIb) or higher, positive PCX expression was found in the urine, suggesting the presence of enough podocytes in the urine. The percentage of fluorescence positive area out of the total glomerular area of PCX in the renal tissues was negatively correlated with the total number of urinary podocytes (r=-0.637, P<0.01). CONCLUSION Podocyte injury plays a certain role in the pathological progression of HSPN. The urinary detection of podocytes can reflect the degrees of pathological damage in HSPN.

Sympathetic nervous system level and ambulatory blood pressure in children with primary nephrotic syndrome

OBJECTIVE To explore the change in ambulatory blood pressure monitoring (ABPM) value and the sympathetic nervous system (SNS) level in children with primary nephrotic syndrome(PNS) and their relationship. METHODS ABPM and casual blood pressure(CBP) were tested in 114 children with PNS and 12 normal children as a control group. The 24-h urine noradrenaline(NA), adrenaline(A) and dopamine(DA) content were detected through high-performance liquid chromatography with electrochemical luminescence and the correlation with ABP was analyzed. RESULTS Among 114 children with PNS, 101 had elevated blood pressure (88.6%), 45 showed high incidence of masked hypertension (39.5%), and 80 non-dipper blood pressure (70.2%). Systolic blood pressure level and blood pressure load were greater than diastolic blood pressure. NA, A, and DA levels of the PNS group were significantly higher than those of the control group, while those of the elevated blood pressure group were significantly higher than those of the normal blood pressure group in PNS children. SNS levels were positively correlated with blood pressure levels and blood pressure load, and negatively correlated with night BP decreasing rates. CONCLUSION Children with PNS have high incidence of hypertension with large proportion of masked hypertension and non-dipper blood pressure. Severe masked hypertension classification should be set up. In PNS children, SNS activity is elevated that might evaluate the blood pressure level and decrease blood pressure circadian rhythm.