Increased expression of apoptosis-associated proteins in puromycin aminonucleoside nephrosis.

Increased apoptosis has been reported in acute puromycin aminonucleoside nephrosis (PAN). The aim of this study was to investigate if increased apoptosis is related to increased expression of apoptosis-associated proteins (AAP) in this model of nephrosis. Sprague-Dawley rats were made nephrotic by intraperitoneal injection of one dose of puromycin aminonucleoside. Renal tissues were obtained at 1, 2 and 7 weeks after injection and apoptosis was investigated by TUNEL and by electron microscopy. Fas, Fas ligand, p53, Bax and Bcl-2 expressions were analyzed by the respective monoclonal and polyclonal antibodies, using indirect immunofluorescence. In the glomerulus of nephrotic animals, increased apoptosis was accompanied with increased expression of p53, Fas and Bax. In the interstitium, high expression of apoptosis, Fas, Fas-L and Bax were observed and in tubules increased apoptosis was accompanied with increased expression of p53, Fas and Fas-L. Bcl-2 was increased in interstitium and tubules during PAN. The incidence of apoptosis during PAN was correlated with the expression of AAP in glomerulus (p53), interstitium (Fas, Fas-L and Bax) and tubules (Fas, Fas-L, p53 and Bcl-2). There was correlation between Fas and Fas-L expression in interstitium and tubules. About 4% of glomerular and 25% of tubular p53 positive cells were apoptotic cells. The data suggest that increased local expression of AAP could contribute to renal apoptosis in the glomerular, interstitial and tubular compartments during this experimental model of nephrosis.

Increased expression of apoptosis-associated proteins in puromycin aminonucleoside nephrosis

Estudios previos han demostrado la presencia de apoptosis en el tejido renal de ratas con nefrosis por aminonucleósido de puromicina (NAP). Este estudio está orientado a determinar si la expresión de la apoptosis está relacionada con aumento en la expresión de proteínas asociadas a la apoptosis (PAP) durante el curso de NAP. Se utilizaron ratas Sprague. Dawley las cuales fueron hechas nefróticas con una inyección única intraperitoneal de aminonucleósido de puromicina. Los controles fueron ratas inyectadas sólo con el vehículo. Se obtuvieron tejidos renales a las 1, 2 y 7 semanas después de la inyección y se analizó la apoptosis por TUNEL y microscopia electrónica y Fas, Fas-L, p53, Bax y Bcl-2 mediante la inmunofluorescencia indirecta, usando anticuerpos policlónales y monoclonales. Se encontró incremento en la apoptosis en el glomérulo de los animales con NAP, acompañado con incremento en la expresión de p53, Fas y Bax. En el intersticio se incrementaron la apoptosis y la expresión de Fas, Fas-L y Bax y en los túbulos el aumento de la apoptosis se acompañó de aumento de p53, Fas, Fas-L. Bcl-2 se incrementó en intersticio y túbulos. La incidencia de apoptosis en este modelo estuvo correlacionada con la expresión de PAP en glomérulo (p53), intersticio (Fas, Fas-L y Bax) y en túbulos (Fas, Fas-L, p53 y Bcl-2). Hubo correlación entre las expresiones de Fas y Fas-L en intersticio y túbulos. Cerca del 4 por ciento en el glomérulo y el 25 por ciento en túbulos de las células p53 positivas estaban en apoptosis. Estos datos sugieren que una expresión aumentada de las PAP en glomérulo, intersticio y túbulo puede estar relacionada con el incremento de la apoptosis en los diferentes compartimientos renales durante este modelo experimental

Gingivitis and anti-neutrophil cytoplasmic antibodies in children and adolescents suffering from Leukemia.

INTRODUCTION: Systemic sickness can originate and proliferate alterations in the periodontium. The presence of Anti-neutrophil Cytoplasmic Antibodies (ANCA) in patients suffering destructive periodontal disease and systemic illness has been widely proven. OBJECTIVE: To determine the existent relation between gingivitis and ANCA in children and adolescents suffering from leukemia. These patients were examined at the Autonomous Services of the University Hospital in Maracaibo, Venezuela, and at the Hospital of Pediatrics Foundation in Zulia State, Venezuela. MATERIALS AND METHODS: 40 patients ranging from 6 to 16 years of age were included in a controlled study. 20 patients suffering from acute leukemia constituted an experimental group, and 20 more patients without apparent systemic sickness who formed a control group. All 40 patients underwent clinical evaluation, and periodontal tissue radiographic evaluation and assessment of ANCA through an enzyme-linked immunoasorbent assay (ELISA); this was done using an IMMCO Diagnostic commercial kit. RESULTS: No Significant differences in the gingivitis average index, plaque and bone loss between the experimental and the control group were evidenced. A significant correlation between gingivitis and ANCA was not evidenced either. Nevertheless, 7 out of 20 patients of the experimental group turned out to be ANCA positive. In contrast, no positive cases were reported in the control group. (p < 0.05 Fisher Test). CONCLUSION: The results of this study suggest that the presence of ANCA is probably related to ongoing immune alterations in patients suffering from leukemia but not related to gingivitis.

Increased production of chemotactic cytokines and elevated proliferation and expression of intercellular adhesion molecule-1 in rat mesangial cells treated with erythrogenic toxin type B and its precursor isolated from nephritogenic streptococci.

BACKGROUND: Previous reports have demonstrated the presence of streptococcal erythrogenic toxin type B (ETB) as well as proliferation and expression of adhesion molecules along with leukocyte infiltrations in biopsies from patients with acute post-streptococcal glomerulonephritis (APSGN). The purpose of the present study was to correlate infiltrative and proliferative events with interactions between ETB or its precursor (ETBP) and intrinsic mesangial cells. METHODS: Rat mesangial cells were cultured with ETB or ETBP (50 micro g/ml) while measuring production of monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-2 (MIP-2) and while examining proliferation and expression of intercellular adhesion molecule-1 (ICAM-1). After 24, 48 and 96 h of incubation, MCP-1 and MIP-2 in culture supernatants were assessed by enzyme-linked immunosorbent assay (ELISA). Cells were assessed for proliferation by incorporation of radioactive thymidine and expression of ICAM-1 was measured by indirect immunofluorescence and by cellular ELISA. RESULTS: Compared with controls, treatment with either ETBP or ETB significantly increased MCP-1 and MIP-2 levels in mesangial cell cultures. Mesangial cells also showed elevated proliferation at 96 h of culture when treated with streptococcal proteins. Although production of MCP-1 and MIP-2 was not correlated with proliferation, treatment with ETBP resulted in a significant correlation between MCP-1 production and proliferation. Immunofluorescence studies revealed an increased expression of ICAM-1 in ETBP/ETB-treated mesangial cells. In addition, cellular ELISA studies showed increased absorbance in cultures treated with ETBP/ETB. Finally, low serum concentrations in the culture medium potentiated the stimulatory effect of ETB on MCP-1 production. CONCLUSIONS: Our findings, by demonstrating a role for cationic streptococcal ETB or ETBP in the induction of chemotactic molecules as well as the proliferation and expression of adhesion molecules, delineate an additional possible pathway for the pathogenesis of APSGN.