Veterinary drugs found in Shropshire.
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Animals↗
Biomedical subjects
D C Harris
Publications and source records attributed to D C Harris.
A comparison of day 5 and day 6 blastocyst transfers.
OBJECTIVE: To compare implantation and pregnancy rates according to the day of embryo transfer (day 5 or 6 after oocyte retrieval) when transfer was postponed until expanded blastocysts developed. DESIGN: Retrospective clinical study. SETTING: Private ART center. PATIENT(S): One-hundred and eighty-three women undergoing blastocyst-stage embryo transfer following in vitro fertilization. INTERVENTION(S): Bipronucleate oocytes were grown for up to 144 hours and subsequently transferred only when at least one embryo attained the expanded blastocyst stage. MAIN OUTCOME MEASURE(S): Implantation and pregnancy rates. RESULT(S): Blastocysts transferred on day 5 implanted at nearly twice the rate of blastocysts transferred on day 6 (36.3% vs. 19.0%). Pregnancy rates were also almost twice as high among the day 5 transfer patients (59.3% vs. 32.3%). In addition, more blastocysts developed (3.6 vs. 2.4), and more were transferred (2.7 vs. 2.3) to the day 5 transfer patients, although the proportion of expanded blastocysts among the blastocysts that were transferred was the same for the two groups (91.7% vs. 93.6%). CONCLUSION(S): Embryos that develop to the expanded blastocyst stage and are transferred on day 5 after retrieval are approximately twice as likely to implant compared to those for which expansion and transfer are delayed until day 6.
Adult↗
Dramatic declines in implantation and pregnancy rates in patients who undergo repeated cycles of in vitro fertilization with blastocyst transfer after one or more failed attempts.
OBJECTIVE: To compare the outcome of second and third cycles of in vitro fertilization with blastocyst transfer to the outcome of first attempts at IVF with blastocyst transfer. DESIGN: Retrospective study. SETTING: Private ART center. PATIENT(S): Three hundred and four patients undergoing treatment with in vitro fertilization with blastocyst transfer, 87 of which underwent at least one cycle of re-treatment after failing to achieve pregnancy in their first cycle. INTERVENTION(S): Bipronucleate oocytes were grown for up to 144 hours and subsequently transferred when at least one embryo attained the expanded blastocyst stage. MAIN OUTCOME MEASURE(S): Pregnancy and implantation rates. RESULT(S): Pregnancy rates per retrieval were significantly higher for patients undergoing their first cycle of in vitro fertilization with blastocyst transfer (36%) compared to those undergoing their second (19%) or their third (9%) cycles of treatment. Implantation rates per embryo were also higher for first cycles of in vitro fertilization with blastocyst transfer (30%) compared to second (18%) or third cycles (8%). CONCLUSION(S): Pregnancy and implantation rates decline dramatically in repeated cycles of in vitro fertilization with blastocyst transfer following one or more unsuccessful cycles of in vitro fertilization with blastocyst transfer.
Adult↗
Quantitative grading of a human blastocyst: optimal inner cell mass size and shape.
OBJECTIVE: To investigate the predictive value of quantitative measurements of blastocyst morphology on subsequent implantation rates after transfer. DESIGN: Prospective observational study. SETTING: Private assisted reproductive technology center. PATIENT(S): One hundred seventy-four IVF patients receiving transfers of expanded blastocyst-stage embryos on day 5 (n = 112) or day 6 (n = 62) after oocyte retrieval. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Blastocyst diameter, number of trophectoderm cells, inner cell mass (ICM) size, ICM shape, and implantation and pregnancy rates. RESULT(S): Blastocyst diameter and trophectoderm cell numbers were unrelated to implantation rates. Day 5 expanded blastocysts with ICMs of >4,500 microm(2) implanted at a higher rate than did those with smaller ICMs (55% vs. 31%). Day 5 expanded blastocysts with slightly oval ICMs implanted at a higher rate (58%) compared with those with either rounder ICMs (7%) or more elongated ICMs (33%). Implantation rates were highest (71%) for embryos with both optimal ICM size and shape. Pregnancy rates were higher for day 5 transfers of optimally shaped ICMs compared with day 5 transfers of optimally sized ICMs. CONCLUSION(S): Quantitative measurements of the inner cell mass are highly indicative of blastocyst implantation potential. Blastocysts with relatively large and/or slightly oval ICMs are more likely to implant than other blastocysts.
Adult↗
Role of CD8(+) cells in the progression of murine adriamycin nephropathy.
BACKGROUND: Many studies have shown that interstitial inflammation in human and experimental renal disease is characterized by T-cell infiltration, but published data on the involvement of inflammatory cell subsets in progressive tubulointerstitial lesions are often conflicting. A previous study suggested a role for cytotoxic T lymphocytes in the damaging effect of CD4(+) T-cell depletion in murine adriamycin (ADR) nephropathy, a model of focal segmental glomerulosclerosis (FSGS), and tubulointerstitial inflammation. The aim of this study was to investigate the role of CD8(+) cells in this model. METHODS: Male BALB/c mice were treated with five intraperitoneal injections of anti-CD8 monoclonal antibody (mAb), beginning from five days after ADR treatment, when overt proteinuria was established. Seven mice in each of groups A (ADR + mAb), B (ADR only), and C (saline treated, age matched) were sacrificed at week 6. Changes in renal function and histopathological features were assessed. Tubulointerstitial inflammation and glomerular inflammation were examined immunohistochemically. RESULTS: mAb treatment reduced CD8(+) cell levels to <2% of normal in spleen. Proteinuria in group A was no different from that in group B at week 6, but was markedly higher than in group C. Creatinine clearance was significantly ameliorated by anti-CD8 treatment (71.8 +/- 4.9 microL/min vs. 29.2 +/- 2.8 in group B and 81.9 +/- 3.7 in group C). Morphometric analysis showed less FSGS in group A compared with group B (6.5 +/- 1.9 vs. 13.0 +/- 2.8, P < 0.001), as well as less tubular atrophy (indicated by increased ratio of tubule cell height to tubular diameter, 0.25 +/- 0.24 in group A vs. 0.04 +/- 0.02 in group B, P < 0.05). CD8 depletion also reduced interstitial expansion (6.3 +/- 2.2% vs. 16.4 +/- 3.1 in group B, P < 0.001) and fibrosis (P < 0.01). Macrophage infiltration in tubulointerstitium was less in group A than in group B (P = 0.052). The number of interstitial CD4(+) cells appeared to increase after anti-CD8 treatment, but was not statistically different between groups A and B. CONCLUSION: Anti-CD8 treatment protects against renal functional and structural injury in this murine model of chronic proteinuric renal disease.
Animals↗
Depletion of CD4(+) T cells aggravates glomerular and interstitial injury in murine adriamycin nephropathy.
BACKGROUND: CD4(+) T cells play an important role in various types of immunologic renal disease, including lupus nephritis, IgA nephropathy, and crescentic glomerulonephritis. CD4(+) T cells are also major infiltrating lymphocytes in chronic tubulointerstitial inflammation associated with nonimmunological renal diseases. We suspected that CD4(+) T cells might contribute to disease progression and loss of renal function in chronic proteinuric renal disease (CPRD). To investigate this possibility, the effect of monoclonal antibody against CD4(+) lymphocytes (anti-CD4) was studied in a murine model (adriamycin nephropathy) of CPRD. METHODS: Adriamycin nephropathy was produced in male BALB/c mice by a single intravenous injection of adriamycin (11 mg/kg). Anti-CD4 was given by intraperitoneal injection following the development of proteinuria at days 5, 6, 7, 21, and 37 after adriamycin. After six weeks, renal function and histology were studied by histomorphometry, immunohistochemistry, and flow cytometry. RESULTS: Flow cytometric analysis showed a marked decrease in the number of CD4(+) T cells in blood and spleen of the antibody-treated animals (N = 7, P < 0.01). Adriamycin plus CD4(+) depletion mice had significantly greater mesangial expansion, glomerular sclerosis, and interstitial expansion than the mice on adriamycin alone. Interstitial infiltration with macrophages and CD8(+) cells was significantly increased in adriamycin plus CD4(+) depletion mice. Creatinine clearance (17.5 +/- 0.54 vs. 29.2 +/- 0.89 microL/min, P < 0.001) was significantly worse in the adriamycin plus CD4(+) depletion mice than in adriamycin alone mice and correlated with histologic change in glomeruli and interstitium. CONCLUSIONS: Depletion of CD4(+) T cells promotes glomerular and interstitial injury in mice with established adriamycin nephropathy. These findings suggest that CD4(+) T cells have a protective role against the progression of adriamycin nephropathy.
Animals↗
Early administration of PDTC in adriamycin nephropathy: effect on proteinuria, cortical tubulointerstitial injury, and NF-kappaB activation.
The persistence of NF-kappaB independent inflammatory signals in the cortical tubulointerstitium may explain the incomplete suppression of interstitial monocyte accumulation by the antioxidant NF-kappaB inhibitor, pyrrolidine dithiocarbamate (PDTC), in nephrotic rats with established Adriamycin nephropathy (AN). Because PDTC is known to have anti-proteinuric effects, in this study we investigated whether earlier commencement, during the pre-nephrotic phase of AN, would be more effective in reducing interstitial monocyte accumulation. Male Wistar rats with AN received either vehicle or PDTC (50 mg/kg bd i.p.i.) from d7 until d30 (n = 8 per group). On d30, PDTC reduced renal cortical lipid peroxidation (43%), wet kidney weight and tubulointerstitial injury in AN, but did not decrease proteinuria. Accordingly, inhibition of interstitial ED-1 accumulation remained incomplete (52%). Interestingly, the early administration of PDTC in AN, induced polyuria and renal cortical NF-kappaB DNA-binding activity was reduced by only 35%. These results suggest that: (i) the combination of an anti-proteinuric agent with PDTC may be required to completely suppress interstitial monocyte cell accumulation in AN and, (ii) the timing and duration of PDTC therapy are an important determinant of its efficacy to reduce NF-kappaB activation, in vivo.
Animals↗
Tubulointerstitial renal disease.
Tubulointerstitial damage, in progressive chronic renal disease of all types, arises because of a complex interplay between factors in the tubular lumen, tubular epithelial cells, peritubular capillaries, resident and infiltrating interstitial cells and extracellular matrix. Particularly in proteinuric renal disease, tubular epithelial cells play a central role in orchestrating these events. In response to mediators arising systemically, in the tubular lumen or from other renal cells, tubular epithelial cells undergo a complex series of structural and functional changes and produce a bewildering number of soluble and fixed mediators, which in turn lead to interstitial inflammation and fibrosis. Knowledge of these interactions has increased exponentially over the past decade, and has defined a number of new targets for treatment. Both expansion and consolidation of this knowledge is needed to determine which of these targets holds the most promise for future treatment.
Humans↗
Molecular mechanisms by which iron induces nitric oxide synthesis in cultured proximal tubule cells.
Nitric oxide (NO) levels are increased after exposure of cultured proximal tubule cells (PTC) to non-haem iron, potentially contributing to PTC injury in disease states associated with increased iron exposure, including proteinuric renal disease. The mechanisms underlying this observed increase were investigated. After 3 h exposure to 400 microM nitrilotriacetate (NTA)-Fe, inducible nitric oxide synthase (iNOS) mRNA expression was significantly increased, with a corresponding increase in iNOS protein after 12 h. The nuclear binding activity of NFkappaB with 400 microM NTA-Fe was increased, and pyrrolidine dithiocarbamate (PDTC), an antioxidant inhibitor of NFkappaB, prevented both activation of NFkappaB and NO production in response to NTA-Fe. Inhibition of protein tyrosine kinase reduced iNOS mRNA, iNOS protein levels and NO production in response to NTA-Fe. The effect of tyrosine kinase inhibition on NFkappaB activation was variable, with herbimycin but not genistein having an inhibitory effect. Activation of either protein kinase A or C increased iNOS mRNA and protein levels, and NO production in response to NTA-Fe, whereas only the protein kinase C activator phorbol dibutyrate (PDBu) had a stimulatory effect on NFkappaB activation. The protein kinase A activator forskolin did not alter iron-induced activation of NFkappaB. These data suggest that the observed increase in NO production by PTC in response to iron is due to increased transcription of iNOS. The transcriptional regulation of this response is complex and involves NFkappaB, protein tyrosine kinase and the protein kinases A and C.
Animals↗
Regulation of tubular cell MCP-1 production by intracellular ions: a role for sodium and calcium.
Proximal tubule cells (PTC) in chronic renal disease produce chemokines which cause renal interstitial inflammation, and also transport more Na+ than normal. To investigate whether these two events might be related, monocyte chemoattractant protein-1 (MCP-1) production was examined in rat PTC in primary culture. Amiloride reduced, while ouabain increased levels of MCP-1 mRNA and protein. Amiloride reduced MCP-1 in cells stimulated with ouabain, lipopolysaccharide (LPS) or albumin. Intracellular Na+ rose with ouabain, but not LPS or albumin. Effects of amiloride, ouabain, LPS and albumin were abrogated by sodium-free but not chloride-free culture medium, and were not explained by changes in intracellular pH. Intracellular Ca2+ rose with ouabain, LPS or albumin and sodium-free medium. BAPTA-AM reduced intracellular Ca2+ and MCP-1 mRNA levels in unstimulated cells, and cells stimulated with ouabain, LPS or albumin. Thus, amiloride and ouabain may alter tubular cell MCP-1 by changing intracellular Na+, with secondary changes in intracellular Ca2+, whereas stimulation by LPS and albumin may involve Ca2+ directly.
Acid-Base Equilibrium↗
Induction of proteinuric chronic glomerular disease in the rat (Rattus norvegicus) by intracardiac injection of doxorubicin hydrochloride.
Adriamycin nephropathy (AN) is a widely used nonimmune-mediated rat model of proteinuric chronic glomerular disease and is usually induced by a single intravenous injection of doxorubicin hydrochloride (DX) into the tail vein. However, this route can be associated with local skin necrosis and variability in disease induction and poses an occupational hazard to the investigator. Here we describe a simple technique of administering DX (1.7 mg) to ketamine:xylazine-sedated adult male Wistar rats (mean +/- 1 standard deviation, 238 +/- 8 g; n = 28) by using a single substernal intracardiac injection. The procedure was associated with minimal morbidity and mortality (1 death related to anesthesia). By day 21, severe nephrotic syndrome with effacement of glomerular epithelial cell foot processes and diffuse cortical tubulointerstitial injury was induced in all animals. Therefore, intracardiac injection of DX is a safe and consistent method of inducing AN in the rat and provides an alternative to the tail-vein route.
Animals↗
Predictive value of 72-hour blastomere cell number on blastocyst development and success of subsequent transfer based on the degree of blastocyst development.
OBJECTIVE: To determine the predictive value of 72-hour blastomere cell number on blastocyst development and to compare success rates of subsequent transfer based on the degree of blastocyst development. DESIGN: Retrospective clinical study. SETTING: Private assisted reproductive technology center. PATIENT(S): Ninety-three women aged 32.0 +/- 5.1 years undergoing oocyte retrieval for IVF. INTERVENTION(S): Bipronucleate oocytes obtained from IVF were grown for up to 168 hours after fertilization and subsequently transferred at the blastocyst stage. MAIN OUTCOME MEASURE(S): Percentages of embryos developing to blastocyst from 72-hour embryos by blastomere cell number and subsequent implantation and pregnancy rates of transferred blastocysts. RESULT(S): Rates of blastocyst formation and expansion increased as cell numbers at 72 hours increased. Implantation rates were 43% for embryos transferred to women receiving only expanded blastocysts and 17% for embryos transferred to women receiving one or more less developed blastocysts. Pregnancy rates were higher for women receiving only expanded blastocysts than for women receiving one or more less developed blastocysts, although the difference was not significant. CONCLUSION(S): More developed 72-hour embryos are more likely to become blastocysts and expand. Implantation rates are greater for the transfer of expanded rather than unexpanded blastocysts.
Adult↗
Identification of a fourth cheY gene in Rhodobacter sphaeroides and interspecies interaction within the bacterial chemotaxis signal transduction pathway.
The Escherichia coli chemotaxis signal transduction pathway has: CheA, a histidine protein kinase; CheW, a linker between CheA and sensory proteins; CheY, the effector; and CheZ, a signal terminator. Rhodobacter sphaeroides has multiple copies of these proteins (2 x CheA, 3 x CheW and 3 x CheY, but no CheZ). In this study, we found a fourth cheY and expressed these R. sphaeroides proteins in E. coli. CheA2 (but not CheA1) restored swarming to an E. coli cheA mutant (RP9535). CheW3 (but not CheW2) restored swarming to a cheW mutant of E. coli (RP4606). R. sphaeroides CheYs did not affect E. coli lacking CheY, but restored swarming to a cheZ strain (RP1616), indicating that they can act as signal terminators in E. coli. An E. coli CheY, which is phosphorylated but cannot bind the motor (CheY109KR), was expressed in RP1616 but had no effect. Overexpression of CheA2, CheW2, CheW3, CheY1, CheY3 and CheY4 inhibited chemotaxis of wild-type E. coli (RP437) by increasing its smooth-swimming bias. While some R. sphaeroides proteins restore tumbling to smooth-swimming E. coli mutants, their activity is not controlled by the chemosensory receptors. R. sphaeroides possesses a phosphorelay cascade compatible with that of E. coli, but has additional incompatible homologues.
Amino Acid Sequence↗
Lipopolysaccharide-induced MCP-1 gene expression in rat tubular epithelial cells is nuclear factor-kappaB dependent.
BACKGROUND: Endotoxin is an important factor in the development of acute renal failure related to infection and in acceleration of chronic nephritis. Lipopolysaccharide (LPS; the major component of endotoxin) is one of the most potent triggers for renal cells to produce monocyte chemoattractant protein-1 (MCP-1), a key cytokine involved in immune cell recruitment into the renal interstitium in acute and chronic renal diseases. Knowledge about the transcriptional regulation of MCP-1 in renal tubular epithelial cells in response to LPS is incomplete. METHODS: Transcriptional regulation of MCP-1 was investigated in rat proximal tubule cells (PTCs) in primary culture and was exposed to LPS using electromobility shift assay and supershift analysis for nuclear factor-kappaB (NF-kappaB) and Western blot for the NF-kappaB inhibitory protein IkappaB. To prove the role for NF-kappaB, activator protein (AP-1), and sequence-specific transcription factor (Sp1), mutation and deletion analysis was performed using a 3.5 kb fragment of rat MCP-1 5'-flanking region inserted into a luciferase reporter construct transfected into tubular epithelial cell line (NRK-52E). RESULTS: LPS increased NF-kappaB in a dose- and time-dependent manner, which paralleled that of MCP-1 mRNA expression. IkappaBalpha decreased within 30 minutes of LPS treatment, but returned to basal levels by two hours. IkappaBbeta levels were depressed within one hour and remained low throughout the culture period after LPS stimulation. The activity of the transfected 5'-flanking region of the MCP-1 gene increased nearly threefold after LPS stimulation. Mutation or deletion of NF-kappaB binding sites, located in the enhancer region of the 5'-flanking region, resulted in a total loss of LPS-induced increase in luciferase activity. Mutation of putative AP-1 and Sp1 sites, located in the proximal promoter region of MCP-1, reduced basal luciferase activity in unstimulated cells, but had no effect on LPS-stimulated luciferase activity. CONCLUSIONS: These studies prove that NF-kappaB is critical for LPS-induced MCP-1 transcription, and AP-1 and Sp1 are essential for basal expression of MCP-1 in rat tubule cells. The species-specific nature of transcriptional regulation of MCP-1 has important implications for the delineation of treatment to prevent endotoxin-mediated renal injury.
Animals↗
Progressive adriamycin nephropathy in mice: sequence of histologic and immunohistochemical events.
BACKGROUND: As an experimental analogue of human focal glomerular sclerosis (FGS), adriamycin (ADR)-induced nephropathy is well-characterized in rats. Previously, this model has not been fully established in mice. The extension of this model to the mouse would be useful in the application of genetic and monoclonal antibody technology to characterize mechanisms of progressive renal disease. Herein, we describe a stable and reproducible murine model of chronic proteinuria induced by ADR. METHODS: Male BALB/c mice were intravenously injected with a single dose of ADR (10 to 11 mg/kg). Seven mice were sacrificed at weeks 1, 2, 4, and 6. Renal function, quantitative morphometric analysis, and electron microscopic studies were performed. Peripheral CD4+ and CD8+ T cells were evaluated using flow cytometric analysis of splenocytes. The leukocytic inflammatory pattern was analyzed by immunohistochemical examination. RESULTS: Overt proteinuria was observed from day 5 and remained significantly elevated throughout the study period. A focal increase in reabsorption droplets in tubular cells appeared at weeks 1 and 2, and numerous intraluminal casts were present after two weeks. Glomerular vacuolation and mild FGS appeared at week 4. At week 6, extensive focal and even global glomerular sclerosis, associated with moderate interstitial expansion and severe inflammation, were observed. A prominent macrophage infiltration appeared within both interstitium and glomeruli at week 2, followed by accumulation of both CD4+ and CD8+ T cells in interstitium but not glomeruli. There were almost no B lymphocytes seen at any time. CONCLUSION: This model should be useful in unraveling the pathogenesis of glomerular and interstitial inflammation and fibrosis in chronic proteinuric renal disease.
Animals↗
Determinants of haemoglobin carbamylation in haemodialysis and peritoneal dialysis patients.
BACKGROUND: Carbamylation is an irreversible process of non-enzymatic modification of proteins by the breakdown products of urea. For haemoglobin (Hb), the extent of carbamylation is a marker of urea exposure and has been proposed as an indicator of the control of uraemia by dialysis, analogous to the use of Hb glycosylation in diabetic patients. METHODS: We performed a cross-sectional study of haemodialysis (HD) and peritoneal dialysis (PD) patients in order to study potential determinants of carbamylated Hb (CarbHb) and to investigate the relationship between CarbHb and established measures of dialysis dose/adequacy by multivariate analysis. RESULTS: In 80 HD patients, CarbHb was independently predicted by post-dialysis urea (r=0.40, P:<0.01), serum albumin (r=0.24, P:<0.05) and serum bicarbonate (r=-0.40, P:<0. 05). No correlation was found between CarbHb and measures of dialysis dose/adequacy (Kt/V, urea reduction ratio, weekly dialysis duration, and normalized protein catabolic rate (nPCR)). In 42 PD patients, serum urea was the only significant independent predictor of CarbHb (r=-0.51, P:=0.001). No relationship was found between CarbHb and Kt/V, corrected creatinine clearance (CrCl) or nPCR in PD patients. CONCLUSIONS: Serum urea is the most consistent independent predictor of CarbHb in dialysis patients. This association in combination with the lack of a relationship with conventional measures of dialysis dose and a positive relationship with serum albumin suggest that a single measurement of CarbHb is unlikely to be a useful indicator of the adequacy of dialysis.
Aged↗
Cytokine gene expression in Adriamycin nephropathy: effects of antioxidant nuclear factor kappaB inhibitors in established disease.
BACKGROUND/AIM: Inhibition of nuclear factor kappaB with the antioxidant pyrrolidine dithiocarbamate (PDTC) reduced tubulointerstitial injury in Adriamycin nephropathy (AN), whereas N-acetylcysteine (NAC) was ineffective. Here we hypothesize that PDTC reduces the renal cortical expression of nuclear factor kappaB dependent cytokines in AN. METHODS: Male Wistar rats received a single intravenous injection of doxorubicin hydrochloride (7.5 mg/kg). NAC (150 mg/kg twice daily i.p.), PDTC (50 mg/kg twice daily i.p.), or vehicle were commenced on day 14 and continued until day 30. RESULTS: On day 30, mRNAs of selected cytokines were increased in AN (TNF-alpha 3.4-fold, MCP-1 5.1-fold, IL-10 2.7-fold, TGF-beta1 3.5-fold, all p < 0.05) as determined by RT-PCR. PDTC reduced IL-10 and TGF-beta1 mRNAs (p < 0.05), whereas the upregulation of MCP-1 and TNF-alpha mRNAs was not affected. In contrast, NAC increased TNF-alpha and IL-10 mRNAs (p < 0.05). Nuclear protein levels of activator protein-1 were increased in AN (4.4-fold, p < 0.01) and not significantly altered by PDTC (3.0-fold, p = 0.13) or NAC (5. 2-fold, p = 0.18). CONCLUSIONS: The protective effects of PDTC in AN are not associated with a local reduction in TNF-alpha and MCP-1 gene expression. The latter may be due to continued transactivation by activator protein-1. These data also suggest that IL-10 and TGF-beta1 mRNA expressions are PDTC dependent and have a role in mediating tubulointerstitial injury.
Acetylcysteine↗
Inhibition of nuclear factor-kappaB activation reduces cortical tubulointerstitial injury in proteinuric rats.
BACKGROUND: Protein-induced chemokine expression in proximal tubular cells is mediated by the transcription factor nuclear factor-kappa B (NF-kappaB). We hypothesized that in vivo inhibition of renal NF-kappaB activation would reduce interstitial monocyte infiltration in a rat model of nonimmune proteinuric tubulointerstitial inflammation. METHODS: Male Wistar rats received a single intravenous injection of doxorubicin hydrochloride [adriamycin (ADR), 7.5 mg/kg] and were studied 7, 14, 21, and 28 days later. In a second study, inhibitors of NF-kappaB [N-acetylcysteine (NAC; 150 mg/kg, b.i.d., i.p.), pyrrolidine dithiocarbamate (PDTC, 50 mg/kg, b. i.d., i.p.)] or vehicle were commenced on day 14 after the onset of proteinuria and were continued until day 30. RESULTS: Rats injected with ADR had increased proteinuria (UpV, day 28, 474 +/- 57; control, 18 +/- 2 mg/day; P < 0.01) and cortical tubulointerstitial injury [tubule cell atrophy, interstitial volume, and monocyte/macrophage (ED-1) infiltration]. Electrophoretic mobility shift assay of nuclear extracts from whole cortex of ADR rats demonstrated that NF-kappaB activation (p50/65, p50/c-Rel) increased from day 7 (4.7 +/- 0.2 fold-increase above control; P < 0.01) was maximal at day 28 (6.2 +/- 0.7; P < 0.01) and correlated with UpV (r = 0.63; P < 0.05) and interstitial ED-1 infiltration (r = 0.67; P < 0.01). Chronic treatment of ADR rats with PDTC suppressed NF-kappaB activation (by 73%; P < 0.05) without any effect on UpV. NF-kappaB inhibition with PDTC was accompanied by a reduction in tubule cell atrophy (59%; P < 0.01), interstitial volume (49%; P < 0.05) and ED-1 infiltration (48%; P < 0.01), and cortical lipid peroxidation (41%; P < 0.05) compared with vehicle-treated ADR rats. In contrast NAC had no effect on NF-kappaB activation, tubulointerstitial injury, or UpV in ADR rats. CONCLUSION: The activation of NF-kappaB may have an important role in mediating cortical interstitial monocyte infiltration and tubular injury in nonimmune proteinuric tubulointerstitial inflammation.
Acetylcysteine↗