A retrospective study on the characteristics of renal pathological grades in HSPN children with mild to moderate proteinuria

OBJECTIVE

To investigate the characteristics of renal pathological grades in Henoch-Schönlein purpura nephritis (HSPN) children with mild to moderate proteinuria and the correlation between pathological grade and severity of proteinuria among this population.

METHODS

HSPN children who were presented with mild (150 mg <24 h urinary protein <25 mg/kg) to moderate (25 mg/kg ≤24 h urinary protein <50 mg/kg) proteinuria and performed renal biopsy without steroid ± immunosuppressant treatment in the Second Xiangya Hospital between January 2010 and March 2021 were involved. We retrospectively analyzed the correlation between age, disease course, degree of proteinuria, type of immunoglobulin deposits, C3 deposits in glomeruli and renal pathological grade.

RESULTS

(1) 72 HSPN children including 46 boys and 26 girls were included, with a mean age of onset of 9.01 ± 2.65 years old. The majority of these patients (62.5%) had a disease course between 1 week to 1 month. 51 patients presented with mild proteinuria and 21 patients with moderate proteinuria. (2) Renal biopsy results showed that ISKDC Grade IIIa were both predominant in mild proteinuria group (25, 49%) and moderate proteinuria group (11, 52.4%). 32 patients had grade II (44.4%), 2 had grade IIIb (2.8%), 1 had grade IV (1.4%), and 1 had grade VI (1.4%). There was no correlation between age, disease course and renal pathological grade (p > 0.05). (3) In patients with mild proteinuria (n = 51), 27 (52.9%) HSPN children had a pathological grade ≥ grade III. In patients with moderate proteinuria (n = 21), 13 (61.9%) HSPN children had grade ≥ III. There was no significant difference in the proportion of renal pathological grade between the 2 groups (p > 0.05). (4) There was no significant correlation between glomerular C3 deposits or immunoglobulin deposit types and renal pathological grade (p = 0.776 and p = 0.056 respectively).

CONCLUSION

In HSPN children with mild to moderate proteinuria, longer disease course or heavier urinary protein level is not completely parallel with higher renal pathological grade. ISKDC grade IIIa is the most common pathological grade. Clinicians should pay great attention to the renal injury in patients with mild to moderate proteinuria.

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.

Role of vitamin D3 in regulation of T helper cell 17 and regulatory T-cell balance in rats with immunoglobulin a nephropathy

INTRODUCTION

Dysregulation of CD4+ T cell subsets participates in the pathogenesis of immunoglobulin A nephropathy (IgAN). Vitamin D has immunomodulatory functions. This study aims to investigate the regulatory effect of vitamin D3 on T helper- regulatory T (Th17-Treg) cells balance in rats with IgAN.

MATERIALS AND METHODS

Sprague-Dawley rats were randomly assigned to a normal group (n = 6), an IgAN model group (n = 5), a prednisone treatment IgAN group (n = 6), a 1,25-dihydroxyvitamin D3 IgAN group (n = 6), and prednisone plus 1,25-dihydroxyvitamin D3 treatment group (n = 6). At week 12, the 24-hour urine protein excretion and erythrocyte count and renal pathological changes were determined, and serum interleukin-17 and Treg cell levels were measured in blood.

RESULTS

The urine protein content and the number of erythrocytes were lower in the vitamin D group than in the model group (P < .01), but higher than in the prednisone groups (P < 0.01). The pathological impairments in the glomerular mesangium, renal tubule, and renal interstitium decreased in response to treatment with prednisone with and without 1,25-dihydroxyvitamin D3. Serum interleukin-17 level in the vitamin D and prednisone plus vitamin D groups was lower than in the prednisone group (P < .05). The Treg cells in the vitamin D and prednisone plus vitamin D groups showed higher levels than in the prednisone group (P < .01).

CONCLUSIONS

Vitamin D3 can regulate the Th17/Treg balance and reduce the level of protein and blood in the urine of rats with IgAN.

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

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.

[Regulatory effect of Astragalus membranaceus on the immune disorder in rats with IgA nephropathy]

OBJECTIVE

To study the regulattory effect of Astragalus membranaceus on immune disturbance of the rats with IgA nephropathy.

METHODS

Rats IgA nephropathy (IgAN) model was duplicated by oral feeding of bovine serum albumin (BSA), subcutaneous injection of carbon tetrachloride (CCl4) and injection of lipopolysaccharide (LSP) into vena caudalis. The rats were divided into three groups randomly for the normal, IgAN model group and the group treated with Astragalus membranaceus (treatment group). The treatment group was given the Astragalus membranaceus granules via intragastric administratsion, the normal group and the IgAN model group were given the equal amount of aqua destillata by gastric perfusion. The rats were examined for albuminuria, hematuria and pathological changes of renal tissue and the distribution of TGF-beta and interleukin-5 in renal tissue was determined by immunohistochemistry and the IFN-gamma and IL-4 of cytokine of Th1 and Th2 types were detected in rats IgA nephropathy model by sandwich enzyme linked immunosorbent assay (ELISA).

RESULTS

(1) The hematuria in rats with IgA nephropathy significantly increased compared with normal control group and Astragalus treatment group (P < 0.05). There was significant increase in albuminuria in rats with IgA nephropathy, compared with normal control group and astragalus treatment group (P < 0.01). (2) The pathological change of glomerular mesangium, renal tubules and renal interstitia became serious in rats IgA nephropathy model when compared with normal control group and astragalus treatment group. Immumofluorescence showed renal IgA density in rats IgA nephropathy model was significantly higher than that in the normal control group (P < 0.001) and astragalus treatment group (P < 0.001). (3) The result of immuno histochemistry showed that there was only weak expression of TGF-beta and interleukin 5 in normal renal tissue. The expression of TGF-beta and interleukin 5 in IgA nephropathy model was significantly stronger than those in normal control group (P < 0.05) and astragalus treatment group (P < 0.05). (4) The serum IL-4 levels were (33.74 +/- 7.52) pg/ml in rats IgA nephropathy model, significantly higher than that in normal control group (2.36 +/- 0.85) pg/ml and astragalus treatment group (3.24 +/- 1.13) pg/ml. The IFN-gamma level in serum of rats IgA nephropathy model was (18.79 +/- 3.80) pg/ml, which was significantly higher than that in normal control group (46.53 +/- 5.56) pg/ml and astragalus treatment group (41.28 +/- 2.95) pg/ml.

CONCLUSIONS

The astragalus could lower the level of hematuria and 24 hours-albuminuria of the IgAN model, and amelioratse the change of the renal pathology and reduce the deposit of IgA in glomerular mesangium. The possible mechanism of the effect is that astragalus could regulate the derangement of Th1, Th2, accordingly could improve the level of IL-4 and IFN-gamma in the serum and diminish the expression of cytokine Th2 TGF-beta1 and IL-5 of the renal tissue, and thereby could postpone the development of IgAN.

Assessment of mycophenolate mofetil for treatment of frequently relapsing nephrotic syndrome in children

OBJECTIVE

To investigate the efficacy and adverse effect of mycophenolate mofetil (MMF) in the treatment of frequently relapsing nephrotic syndrome in children.

METHODS

The study population consisted of 37 children (24 simple nephrotic syndrome and 13 nephritis-type syndrome) suffering from frequently relapsing nephrotic syndrome. Patients received 20-30 mg/(kg d) of MMF in conjunction with 1 mg/(kg d) prednisone for 3-6 months.

RESULTS

Out of 24 patients suffered from simple nephrotic syndrome, 17 patients (70.8%) with complete relief, 4 patients (16.7%) with partial relief and 3 patients (12.5%) with non-relief, whereas out of 13 patients suffered from nephritis-type syndrome 6 patients (46.2%) with complete relief, 3 patients (23.1%) with partial relief and 4 patients (30.7%) with non-relief. Eight patients with Minimal Change Disease (MCD) achieved complete relief. Of 23 patients with Mesangial Proliferative Glomerulonephritis (MsPGN) or Membranoproliferative Glomerulonephritis (MPGN), complete relief was observed in 17 patients (73.9%), partial relief in 4 patients (17.4%) and non-relief in 2 patients.

CONCLUSION

These Results suggest that MMF has better efficacy against simple renal disease than against nephritis-type syndrome, and MMF may be more suitable for the treatment of frequently relapsing nephrotic syndrome characterized by proliferative lesions.

[Effects of siRNAs silencing transforming growth factor-beta1 on fibronectin in SD rat masangial cells]

OBJECTIVE

To investigate fibronectin synthesis in SD rat mesangial cells after transforming growth factor-beta1 (TGF-beta1) is silenced by the short interfering RNA (siRNA) expressed by reconstructed pGEFP-C1 vectors.

METHODS

Depending upon the 538th - 556th (A) and 895th - 913th (B) nucleotides of rat TGF-beta1 gene, a nucleotide (A or B) was constructed into a small hairpin nucleotide which was separately (A or B) or together (A plus B) inserted into a pGEFP-C1 vector with three reconstructed pGEFP-C1 vectors separately expressing the siRNAs for A or/and B. TGF-beta1 and fibronectin were dynamically investigated for their interrelationship by ELISA in the supernatant and RT-PCR in their extracted total RNA.

RESULTS

The siRNA hairpin-like molecules were constructed according to the 538th - 556th nucleotides of rat TGF-beta1 gene were able to markedly silence the expression of TGF-beta1 mRNA (P < 0.01) and protein (P < 0.01) at 48 h. Lipfectamin 2000 transfection stimulated the peak secretion of fibronectin at 24 h in the control and the experimental group whose TGF-beta1 was not silenced, but the silence of TGF-beta1 in both experimental groups delayed the top values of fibronectin to 48 h (P < 0.01).

CONCLUSION

The silence of TGF-beta1 by siRNA decreased the fibronectin expression, but the latter was possibly not completely TGF-dependent.

[Ability of catechin to eliminate O2-* and *OH]

OBJECTIVE

To investigate the eliminating ability of catechin to eliminate O2-* and *OH.

METHODS

The ability of catechin to clear away O2-* and *OH was respectively measured by faintness chemiluminescence and spin trapping assay.

RESULTS

IC50 that catechin eliminated O2-* and *OH was 6.16, 0.59 g/mL respectively, and the eliminating ability of catechin was much stronger than that of the extract from liquorice, rosemary, grape pip, giant knotweed and ginkgo leaf.

CONCLUSION

Compared with several important natural plants of antioxidants, the eliminating ability of cathechin is the best.

[Effect of glucocorticoid on glucocorticoid-resistant children with primary nephrotic syndrome]

OBJECTIVE

Glucocorticoid (GC) is the first therapeutic choice of primary nephrotic syndrome (PNS). The response to GC treatment is an important indicator for the outcome of PNS children. Children with GC-resistant PNS present with incomplete or no response to GC, and may herald the progression to end-stage renal failure. However, the detailed mechanism of GC-resistance or GC-sensitive effect in these PNS children has not been clearly elucidated. The previous study by the authors indicated that there was increased expression of GR beta in PBMCs in GC-resistant children with PNS, and the over expression of GR beta resulted in GC resistance via influencing the ability of GR alpha nuclear translocation. To elucidate the relationship between GR beta expression in renal and in PBMCs and the effect of glucocorticoid on glucocorticoid-resistance children with PNS, the expression of GR alpha and GR beta in renal tissue and in PBMCs were detected by immunohistochemistry.

METHODS

Forty children with PNS were divided into two groups, GC-resistant group(20) and GC-sensitive group(20), the expression of GR alpha and GR beta in renal intrinsic cells and in PBMCs were measured with the immunohistochemistry technique. A semiquantitative score was used to evaluate the injury degree of the glomeruli and tubulointerstitium.

RESULTS

Compared with GC-sensitive group, the glomerular pathologic scores (6.91 +/- 1.98) and renal tubular pathologic scores (7.12 +/- 1.62) in GC- resistant group were significantly different (P < 0.01, respectively). GR alpha expressions of renal tissue and PBMCs were higher in the control group (58.3 +/- 2.6, 59.1 +/- 7.2) than those in the GC-sensitive group (40.2 +/- 7.2 and 36.6 +/- 5.1, P < 0.01, respectively) and GC-resistant group (35.0 +/- 8.2 and 36.4 +/- 6.6, P < 0.01, respectively). GR beta expressions of renal tissue and PBMCs were higher in the GC-resistant group (13.8 +/- 3.0 and 12.1 +/- 4.1) and in the GC-sensitive group (6.5 +/- 1.9 and 5.9 +/- 1.0) than that in control group (2.3 +/- 0.4 and 3.2 +/- 1.1, P < 0.01, respectively). GR beta expressions in renal tissue and PBMCs were higher in the GC-resistant group than that in the GC-sensitive group (P < 0.01). Compared with control group, GR beta expressions in PBMCs and in renal tissue were lower than those in mild renal lesion group (5.4 +/- 2.8, 6.46 +/- 2.50), midmedium renal lesion group (8.7 +/- 2.4 and 11.4 +/- 3.7) and (17.1 +/- 0.4 and 18.7 +/- 0.7) in severe renal lesion group (F = 5.8, 15.6, P < 0.01, respectively). GR beta expression of PBMCs had a positive correlation with GR beta expression of renal intrinsic cells (r = 0.651, P < 0.01). GR beta expressions by PBMCs and renal intrinsic cells were positively correlated with renal pathologic scores (r = 0.579 and 0.623, P < 0.01, respectively).

CONCLUSION

GC-resistant children with PNS were related to the increased GR beta expression in PBMCs and renal intrinsic cells. There was no correlation between the GR alpha expressions in PBMCs and in renal intrinsic cells. Increased GR beta expression might decrease the effect of GC via inhibiting the activity of GR alpha.

[Studies on chemical constituents of Cistanche tubulosa (Schenk) R. Wight]

OBJECTIVE

To investigate the chemical constituents of Cistanche tubulosa.

METHOD

The chemical constituents were isolated by solvent extraction together with various chromatographic techniques including preparative HPLC. The structures were elucidated on the basis of chemical evidence and spectral data.

RESULTS

Four iridoid glycosides, one lignan glycoside and one monoterpenoid were isolated from the 95% ethanol extract from the stem of C. tubulosa and identified as adoxosidic acid(I), 8-epiloganic acid(II), geniposidic acid (III), mussaenosidic acid(IV), (+)-syringaresinol-O-beta-D-gluco pyranoside(V) and 8-hydroxygeraniol(VI).

CONCLUSION

Compounds I and VI were isolated from the genus of Cistanche for the first time. Compounds III, IV and V were isolated from this plant for the first time.