TLR9 gene polymorphism (rs187084, rs352140): association with acute rejection and estimated glomerular filtration rate in renal transplant recipients.

The Toll-like receptors (TLRs) are related to innate immunity. TLR9, a member of TLRs, is expressed in immune cell-rich tissues and mediates cellular response. We investigated the association between TLR9 polymorphisms and kidney allograft outcomes. To investigate whether TLR9 polymorphisms are associated with acute rejection after renal transplantation, two single nucleotide polymorphisms (SNPs) of TLR9 gene (rs187084 -1486; rs352140, G2848A) were selected and genotyped by direct sequencing in 342 renal transplant recipients. SNPStats, SNPAnalyzer, Helixtree and Haploview version 4.2 were used to analyse genetic data. Multiple logistic regression models (codominant, dominant, recessive and log-additive) were used to evaluate odds ratios (ORs), 95% confidence intervals (CIs) and P values. Both SNPs, TLR9 rs187084 -1486 and rs352140 G2848A, of recipients were associated with the risk of acute rejection in renal transplantation. C allele of rs187084 -1486 and A allele of rs352140 G2848A were protective genotype for acute rejection (OR 0.6, 95% CI 0.40-0.92; P = 0.018, OR 0.64, 95% CI 0.42-0.98; P = 0.04, respectively). rs187084 -1486 CT and rs352140 G2848A GA genotype were associated with a lower eGFR after a year of renal transplantation. TLR9 polymorphisms, rs187084 and rs352140, of recipients were associated with the risk of acute rejection in renal transplantation. The patients with rs187084 -1486 CT and rs352140 G2848A GA genotype showed a lower eGFR after a year of renal transplantation.

Purple urine bag syndrome: case report and literature review.

Purple urine bag syndrome (PUBS) is a medical syndrome in which there is purple discoloration of the urine of catheterized patients as well as discoloration of the collecting bag and the associated tubing. This rare condition, which mostly affects women, is generally associated with catheter-associated urinary tract infection, chronic constipation and alkaline urine. PUBS may be caused by sequential chemical reactions involving tryptophan from food in the gastrointestinal tract. The clinical course of PUBS is generally benign, and intensive treatment is not usually needed. We present 3 cases of this unusual and interesting phenomenon and a literature review.

Prognostic relevance of clinical and histological features in IgA nephropathy treated with steroid and angiotensin receptor blockers.

BACKGROUND: The prognostic relevance of clinical and histological features on renal outcome has not been assessed in patients with IgA nephropathy (IgAN) treated with the combination therapy of steroid and angiotensin receptor blockers (ARB). METHODS: A prospective trial of a combination of steroid and ARB was performed in 50 patients with IgAN, proteinuria and serum creatinine levels < 2 mg/dl. RESULTS: Over a mean follow-up period of 4 years, the combination therapy reduced proteinuria and hematuria and improved renal function in most patients. The mean change in estimated GFR (eGFR) was + 0.30 +/- 0.74 ml/min/1.73 m2/month. Forty-three patients (86%) exhibited stable renal function and 7 patients (14%) reached the primary end point of a (3) 20% decrease in eGFR from baseline levels. Between the nonprogressive and progressive patients, there were significant differences in the levels of urine protein/ creatinine excretion ratio (PCR) at baseline and throughout the follow-up period as well as baseline eGFR and degree of glomerular crescents (p < 0.05). Forty (80%) and 24 patients (48%) had a urine PCR < 1 and < 0.3 g/g, respectively, at their last follow-up. Renal survival was better in patients who had initial urine PCR < 3 g/g as well as final PCR < 1 g/g. Regression analysis revealed that the final urine PCR and age were critical determinants of slope of the eGFR by both univariate and multivariate analyses. However, eGFR, pathologic findings, systolic BP, proteinuria, and body mass index at the initial presentation were not predictive of slope. CONCLUSION: Our results indicate that achieving a low urinary protein excretion is the main determinant for the good outcome in patients treated with combination therapy.

Association of MCP-1 and CCR2 polymorphisms with the risk of late acute rejection after renal transplantation in Korean patients.

Among the factors modulating transplant rejection, chemokines and their respective receptors deserve special attention. Increased expression of monocyte chemoattractant protein-1 (MCP-1) and its corresponding receptor (chemokine receptor-2, CCR2) has been implicated in renal transplant rejection. To determine the impact of the MCP-1-2518G and CCR2-64I genotypes on renal allograft function, 167 Korean patients who underwent transplantation over a 25-year period were evaluated. Genomic DNA was genotyped using polymerase chain reaction followed by restriction fragment length polymorphism analysis. Fifty-five (32.9%) patients were homozygous for the MCP-1-2518G polymorphism. Nine (5.4%) patients were homozygous for the CCR2-64I polymorphism. None of the investigated polymorphism showed a significant shift in long-term allograft survival. However, a significant increase was noted for the risk of late acute rejection in recipients who were homozygous for the MCP-1-2518G polymorphism (OR, 2.600; 95% CI, 1.125-6.012; P = 0.022). There was also an association between the MCP-1-2518G/G genotype and the number of late acute rejection episodes (P = 0.024). Although there was no difference in the incidence of rejection among recipients stratified by the CCR2-V64I genotype, recipients with the CCR2-V64I GG genotype in combination with the MCP-1-2518G/G genotype had a significantly higher risk of acute or late acute rejection among the receptor-ligand combinations (P = 0.006, P = 0.008, respectively). The MCP-1 variant may be a marker for risk of late acute rejection in Korean patients.

Everolimus-Induced Systemic Serositis After Simultaneous Liver and Kidney Transplantation: A Case Report.

Although everolimus, a mammalian target of rapamycin inhibitor, has been used as a potent immunosuppressive agent in organ transplantation, data regarding its adverse effect profile compared with that of sirolimus in clinical circumstances are limited. A 50-year-old man who underwent simultaneous liver and kidney transplantation 14 months previously was admitted with large pleural effusion, pericardial effusion, and ascites. Laboratory findings and cultures for possible infectious causes were all negative. Pericardial window surgery with drainage of the pericardial fluid was performed on day 3. Pleural and pericardial biopsy revealed non-specific inflammation without evidence of malignant cells. Everolimus was discontinued and replaced by mycophenolate mofetil on day 4. Significant clinical improvement was observed after discontinuation of everolimus, and follow-up echocardiography and chest radiography showed no recurrence of the pericardial or pleural effusion after discharge.

A Promoter Polymorphism in the CD46 Complement Regulatory Protein Gene Is Associated With Acute Renal Allograft Rejection.

OBJECTIVES: CD46 molecule (complement regulatory protein [CD46]), known as a human cell surface receptor, plays an important role in complement and T-cell regulation for organ transplantation. This study was performed to evaluate the association of promoter polymorphism (rs2796267, -496 A/G) of the CD46 gene with acute renal allograft rejection (AR), late acute rejection (LAR), and graft loss (GL) in Korean patients. METHODS: A total of 334 patients with kidney transplants were recruited. Transplantation outcomes were determined in terms of AR, LAR, and GL criteria. The promoter single nucleotide polymorphism (SNP) of CD46 was genotyped by direct sequencing. RESULTS: The rs2796267 SNP exhibited significant differences between the AR group and non-AR group (codominant1 model, P = .012; odds ratio [OR], 0.47 [95% confidence interval, 0.26-0.84]; dominant model, P = .012; OR, 0.50 [95% CI, 0.29-0.86]; and allele distribution, P = .034; OR, 0.64 [95% CI, 0.43-0.94]). In addition, the SNP also exhibited significant associations with LAR (codominant2 model, P = .041; OR, 0.12 [95% CI, 0.02-0.92]; recessive model, P = .005; OR, 0.13 [95% CI, 0.02-0.94]; and allele distribution, P = .038; OR, 0.58 [95% CI, 0.35-0.97]). CONCLUSIONS: This study suggests that the promoter polymorphism (rs2796267, -496 A/G) CD46 gene may be related to susceptibility of AR in Korean kidney transplantation recipients.

Association Interleukin-4 and Interleukin-4 Receptor Gene Polymorphism and Acute Rejection and Graft Dysfunction After Kidney Transplantation.

BACKGROUND: Cytokine genotypes have previously been studied in patients undergoing solid organ transplantation; certain polymorphisms have been implicated in the development of acute rejection (AR) and graft dysfunction (GD). Allograft outcomes determined, in part, by alloimmune responses is mainly mediated by T-cell responses, activated and driven by cytokines. Interleukin-4 (IL-4) is one such cytokine, which exerts its biological effects through binding to the IL-4 receptor (IL-4R) complex on target cells. In the present study, we investigated whether polymorphisms of the IL-4 and/or IL-4R gene were associated with susceptibility to acute AR and GD after kidney transplantation. METHODS: We analyzed 2 single nucleotide polymorphism (SNPs) of IL-4 (rs2243250 and rs2070874) and 3 SNPs of IL-4R (rs1801275, rs2107356, and rs1805010) in 344 kidney transplant recipients. These patients included 62 of whom had developed AR and 215 of whom had GD in 1 year after kidney transplantation. RESULTS: The AR group included 62 patients (45 men and 17 women). There was a statistically significant difference in the male-to-female ratio and the use of tacrolimus in the AR group. The GD group included 215 patients. Patients who developed GD were more likely to be older and have an underlying cause of end-stage renal disease that was unknown compared with patients who did not have GD, the cause of which was typically known. Among the SNPs examined, 1 of the SNPs in the IL-4R gene (ie, rs1801275) showed a statistical association with AR (co-dominant model, P = .061; dominant model, P = .019; and log-addictive model, P = .029). In addition, 1 of the IL-4R SNPs (ie, rs2107356) was statistically associated with GD (dominant model, P = .034). No significant difference in the IL-4 genotype was observed between the AR/GD and non-AR/non-GD subjects. CONCLUSIONS: One IL-4R gene polymorphism (rs1801275) was associated with AR. In addition, a separate IL-4R SNP (rs2107356) was statistically associated with GD after kidney transplantation.

Matrix Metalloproteinase Gene Polymorphisms and New-Onset Diabetes After Kidney Transplantation in Korean Renal Transplant Subjects.

BACKGROUND: New-onset diabetes after transplantation (NODAT) is a serious metabolic complication that may follow renal transplantation. Matrix metalloproteinases (MMPs) contribute to insulin insufficiency and beta-cell dysfunction in a rat model. The MMP-2 concentrations were lower in patients with type 2 diabetes mellitus, and the plasma MMPs levels were related to diabetes. Similar to the pathogenesis of type 2 diabetes mellitus, insulin resistance and insulin secretion dysfunction occur in patients with the development of NODAT. Therefore, we examined the association between NODAT and 11 single-nucleotide polymorphisms (SNPs) located within the 3 genes of MMPs that might be related to NODAT. METHODS: A total of 309 renal transplant recipients without a history of diabetes were included in this study. DNA was extracted from the blood samples of recipients, and we analyzed the association between the development of NODAT and a panel of 11 SNPs within 3 MMP genes (MMP-1, MMP-2, and MMP-3). RESULTS: In terms of allele frequencies, rs243849*C (MMP-2) was significantly higher in patients with NODAT. Two of the 11 (18.1%) SNPs were significantly associated with NODAT development after adjusting for age, sex, and tacrolimus usage: MMP-2 (rs1132896) and MMP-2 (rs243849). In the multiple logistic regression analysis, these 2 SNPs were significantly associated with the development of NODAT in the codominant and recessive or codominant and dominant models. CONCLUSIONS: MMP-2 gene rs1132896 and rs243849 polymorphisms may serve as genetic markers for the development of NODAT. The exact molecular mechanisms still must be clarified.

Bone marrow findings before and after treatment with recombinant human erythropoietin in chronic hemodialyzed patients.

The stimulating effect of rHuEPO on erythropoiesis has been shown in several studies, using bone marrow cell culture or animal models. To investigate the effect of rHuEPO on bone marrow findings in vivo, we studied the bone marrow cellularity, the myeloid: erythroid (M:E) ratio, an estimate of the number of megakaryocytes, any cytomorphologic or maturation abnormalities, and an estimate of the storage iron before and after 3 months of treatment with rHuEPO in 10 chronic hemodialyzed patients. Nine patients showed a slight or moderate decrease of erythropoiesis in bone marrow in comparison to normal bone marrow before rHuEPO treatment. The bone marrow cellularity was a mean of 28.5% and decreased in 8 out of 10 patients compared to normal values. However, megakaryopoiesis and granulopoiesis were normal. Three months of treatment with rHuEPO had increased erythropoiesis in all 10 patients, including one patient whose bone marrow proved to be normal erythropoiesis on baseline examination. The M:E ratio was significantly decreased from 4.0 +/- 1.2:1 to 2.4 +/- 1.1:1 (p < 0.005). The bone marrow cellularity was also increased in 9 patients, except in 1 patient whose specimen was inadequate for diagnosis, after 3 months of treatment with rHuEPO. On baseline examination of bone marrow, iron staining was undetectable in one, low in one, normal in 2 and high in 5 sections. According to grading, iron staining had decreased from 3.1 +/- 1.7 to 2.1 +/- 0.9 (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Association between interleukin-3 gene polymorphism and acute rejection after kidney transplantation.

BACKGROUND: Acute rejection (AR) after kidney transplantation resulting from alloimmune responses has a negative effect on graft survival. AR is mainly caused by T-cell immune responses activated by cytokines, including interleukin (IL)-2, -4, and -7. Many reports have shown that single nucleotide polymorphisms (SNPs) of these cytokines can affect the occurrence of AR. IL-3, which is secreted by activated T cells, can mediate AR. Our study sought to investigate the association between SNPs of the IL3 gene and the occurrence of an AR episode (ARE). METHODS: We analyzed 3 SNPs of IL3 (rs181781, rs2073506, and rs40401) among 330 renal recipients, 60 of whom had developed an ARE. SNPs of the IL3 gene, including 1 exonic SNP (rs40401) and 2 regulatory thought to be promoter SNPs (rs181781 and rs2073506). RESULTS: The genotypes of 60 ARE subjects and the 270 patients without AR demonstrated a significant relationship between genotype frequencies and the SNPs. The occurrence of an ARE was associated with rs181781 (P = .041, dominant model), rs2073506 (P = .009, codominant 1 model; P = .003, dominant model), and rs40401 (P = .014, recessive model). Among haplotypes, AAT showed a significant association with ARE. (P = .0033). CONCLUSION: Our results suggest that IL3 gene polymorphisms were associated with this event.

Immunological abnormalities in patient with IgA nephropathy.

T cell immunity and phagocytic activity were studied in the blood of patients with IgA nephropathy in order to clarify their roles in the pathogenesis of IgA nephropathy. The percentages of total T lymphocytes, helper T cell and suppressor T cells were significantly reduced in patients. A significantly elevated helper T cell/suppressor T cell ratio in patients showed a predominant reduction in suppressor T cells. There was a significant relationship between histologic findings and helper T cell/suppressor T cell ratio in patients. Natural Killer (NK) cell activity was significantly reduced but the lymphocyte response after phytohemagglutinin (PHA) stimulation was not in patients. ConA-induced suppressor cell activity was not depressed despite of a decrease in suppressor T cells in patients. Phagocytic activity of polymorphonuclear leucocytes (PMNs) ingesting yeasts was significantly reduced in patients. Also an inverse correlation was found between serum IgA levels and phagocytic activity of PMN. It is concluded that suppressor T cell defects, depressed phagocytic activity and impaired NK cell activity may play a role in the pathogenesis of IgA nephropathy.

Tumor necrosis factor alpha from peripheral blood mononuclear cells of IgA nephropathy and mesangial cell proliferation.

BACKGROUND: To investigate the role of mononuclear cells and their products on rat mesangial cell proliferation, we evaluated the effect of peripheral blood mononuclear cells (PBMC) culture supernatant of patients with IgA nephropathy on rat mesangial cells 3[H]-thymidine uptake, and measured the concentration of cytokines in the supernatant to find out which cytokine in PBMC culture supernatant has a major influence on mesangial cell 3[H]-thymidine uptake. METHODS: In ten patients with primary IgA nephropathy and 10 normal controls, PBMC were cultured with PHA (20 micrograms/ml) and con-A (10 micrograms/ml) for 24 hours, and supernatants were collected and stored at -70 degrees C until tested. Mesangial cell was cultured for 48 hours at a concentration of 10(4) cells/well with 1:2 or 1:10 diluted PBMC culture supernatant. 3[H]-thymidine uptake into rat mesangial cell was assayed after 18 hour culture. The cytokine concentrations of PBMC culture supernatant were measured by radioimmunoassay. RESULTS: When 1:2 diluted PBMC culture supernatant was added, the supernatant of IgA nephropathy induced higher 3[H]-thymidine uptake into mesangial cell compared with that of normal controls. 3[H]-thymidine uptake induced by 1:2 diluted PBMC culture supernatant was significantly higher than that induced by 1:10 diluted supernatant of IgA nephropathy. The concentration of TNF-alpha in PBMC culture supernatant of the patients with IgA nephropathy was higher than that of normal controls and showed a good correlation with the mesangial cell 3[H]-thymidine uptake. CONCLUSION: It is suggested that the mononuclear cell of IgA nephropathy may have the intrinsic property to produce more TNF-alpha which may be mitogenic to mesangial cells when stimulated with mitogens, and it may be related to the mesangial cell proliferation in IgA nephropathy.

Effect of angiotensin converting enzyme inhibitor on collagen production by cultured mesangial cells.

Cultured mesangial cells (MC) express renin mRNA and generate angiotensin I, supporting the action of local renin-angiotensin system. Also angiotensin II may act like a growth factor and was reported to increase collagen production (CP) in cultured MC. Angiotensin converting enzyme inhibitor is suggested to attenuate development and advancement of glomerulosclerosis, mainly with its hemodynamic effects. Therefore, we investigated the direct effects of enalapril (E) on CP by cultured MC. Rat MC were cultured in DMEM media alone, or containing high glucose (HG: 25 mM) or soluble immune complex (IC) prepared with bovine gamma globulin (BGG) and anti-BGG, with or without E (0.2 microgram/ml). CP was determined after 24 h by [3H] proline incorporation method. E significantly reduced CP by 43% in medium as compared with control (C) (C: 37,210 +/- 4,200 vs C + E: 21,350 +/- 5,080 cpm/well, p < 0.01). CP in medium increased in the presence of HG (123% of C) or IC (147% of C), which was, however, prevented with E (HG + E: 105% of C, IC + E: 116% of C). There were no differences of CP in cell layer between C (3,490 +/- 220 cpm/well) and C + E (3,340 +/- 190 cpm/well), and also no changes after addition of E in HG or IC groups. In conclusion, E directly attenuates CP by MC, even in the presence of HG or IC, independently of its hemodynamic effects.

Circulating factors in sera or peripheral blood mononuclear cells in patients with membranous nephropathy or diabetic nephropathy.

In order to investigate the status of some circulating factors in nephrotic syndrome, we examined the secretion of monocyte chemotactic peptide (MCP)-1, tumor necrosis factor (TNF) alpha or fibronectin in sera or by peripheral blood mononuclear cells (PBMC) from patients with membranous nephropathy (MN), diabetic nephropathy (DN) or minimal change disease (MCD). Also the effects of PBMC or sera on human mesangial cells (MC) were evaluated. Serum TNF alpha levels were higher in patients with MN than in controls, but PBMC exhibited no differences in TNF alpha production between patients and controls. Serum fibronectin levels were higher in patients with MN than in controls. PBMC from diabetic patients with or without nephropathy produced more MCP-1 than cells from controls. When MC were cultured with PBMC supernatants from patients, TNF alpha levels in PBMC supernatants correlated with production of MCP-1 or fibronectin by MC. PBMC supernatants obtained from patients with MCD and MN decreased MCP-1 production by MC, but did not affect thymidine incorporation or fibronectin production by MC. Sera obtained from patients with DN and MCD reduced thymidine incorporation in MC. In summary, serum TNF alpha or fibronectin levels were increased in patients with MN that is known to progress to renal failure. MCP-1 Production was increased by PBMC obtained from diabetic patients with or without nephropathy. Also TNF alpha production by PBMC in individual patients may affect the pathophysiology of their MC.

Role of mononuclear cells of IgA nephropathy on ICAM-1 expression in mesangial cells.

OBJECTIVES: To investigate the possible role of mononuclear cells and their products in the pathogenesis of IgA nephropathy, in vitro expression of ICAM-1 on cultured mouse mesangial cell (MC) was examined after stimulation with mononuclear cell culture supernatant from patients with IgA nephropathy. METHODS: Peripheral blood mononuclear cells (PBMC) were isolated and cultured from 18 patients with primary IgA nephropathy, 8 normal controls and 5 patients with non-IgA nephropathy (FSGS 1, MGN 3, MPGN 1). ICAM-1 expression on cultured mouse MC by TNF-alpha, IL-1 beta and culture supernants of PBMC were analyzed using a cell ELISA method. The concentration of IL-1 beta and TNF-alpha in culture supernatants was measured by using a commercially available radioimmunoassay kit. RESULTS: Addition of human recombinant TNF-alpha induced an increased ICAM-1 expression in a dose-dependent manner. The expression of ICAM-1 was further increased after co-stimulation with TNF-alpha and IL-1 beta. Addition of PBMC culture supernatants into mouse MC induced significantly higher expression of ICAM-1 by supernatants from the patients with IgA nephropathy compared with that from normal controls. The concentration of TNF-alpha and IL-1 beta in supernatants from the patients with IgA nephropathy was significantly higher than that from those with non-IgA nephropathy. CONCLUSION: TNF-alpha and IL-1 released from mononuclear cells induced the up-regulation of ICAM-1 expression and this may be related to the immune pathogenesis of IgA nephropathy.

Clinical course of patients with IgA nephropathy between combined treatment of immunosuppressive agents and ACE inhibitor and ACE inhibitor alone.

BACKGROUND: It has not been clear whether immunosuppressive therapy favorably influences renal function and proteinuria in IgA nephropathy (IgAN). Angiotensin converting enzyme inhibitor (ACEi) has an anti-proteinuric effect in IgAN. A retrospective study was done to see whether the addition of immunosuppressive therapy to ACEi produces a more excellent anti-proteinuric effect and preserves better renal function than ACEi alone. METHODS: A total of 49 patients with proteinuria > 1.0 g/day and serum creatinine concentrations < 1.5 mg/dL were followed-up from at least 1 year to 9 years. Among them, 25 patients were treated with the combination of cyclophosphamide, prednisolone and ACEi while the other 24 were treated with ACEi alone. RESULTS: The combination therapy or ACEi alone both reduced proteinuria with significant value (the combination group: from 5.74 +/- 5.08 to 2.29 +/- 2.77 g/day, ACEi group: from 3.85 +/- 2.54 to 1.68 +/- 1.91 g/day), while no significant differences in reduction of proteinuria were noticed between the two groups. There was no significant elevation of serum creatinine in both groups during follow-up (the combination group: from 0.91 +/- 0.20 to 1.03 +/- 0.38 mg/dL, ACEi group: from 0.93 +/- 0.27 to 0.99 +/- 0.37 mg/dL). This study showed no significant differences in the change in slope of 1/serum creatinine levels during the follow-up period between the two groups. CONCLUSION: We conclude that immunosuppressive therapy may not be beneficial in patients with proteinuric IgAN. ACEi may be a valuable therapeutic agent avoiding serious side effects of immunosuppressive agents.

Early increased renal procollagen alpha 1(IV) mRNA levels in streptozotocin induced diabetes.

Changes in renal procollagen mRNA levels were measured shortly after the induction of streptozotocin induced diabetes in the rat. "Medullary" procollagen alpha 1(IV) levels seven days after diabetes induction was significantly higher in untreated diabetic rats (DM, N = 12; 244 +/- 57% of the mean control value), than in diabetic rats receiving small doses of insulin insufficient to achieve euglycemia (NPH, N = 10; 87 +/- 12%) and in diluent injected nondiabetic control rats (C, N = 15; 100 +/- 12%; P less than 0.01, DM vs. C and DM vs. NPH). "Medullary" procollagen alpha 1(I) mRNA levels were numerically increased in DM to a lesser degree (141 +/- 5%, ANOVA not significant) compared to C (100 +/- 13%), and this small increment was further normalized by insulin treatment (NPH, 120 +/- 11%). A trend for increased beta-actin mRNA levels in DM did not reach significance (P greater than 0.05). Increases in "medullary" procollagen mRNA levels did not correlate with kidney weight, glomerular tuft volume, creatinine clearance, food intake, or body weight gain, and occurred when renal morphology was normal by light microscopy. Statistically significant but weak correlations were noted between the serum glucose levels and "medullary" procollagen alpha 1(IV) mRNA levels (r = 0.43, P less than 0.05). In addition, weak correlations were noted between glycosuria and "medullary" procollagen alpha 1(I) levels (r = 0.38, P less than 0.05). In situ hybridization studies localized the increased procollagen alpha 1(IV) mRNA levels predominantly in the DM group primarily in the deep cortex and medullary outer stripe of proximal tubules. Glomerular procollagen alpha 1(IV), alpha 1(I), alpha 1(III) and beta-actin mRNA levels were not increased in untreated diabetic rats 7 or 28 days after diabetes induction. Thus, tubular procollagen alpha 1(IV) mRNA levels increased prior to any measurable change in glomerular levels and were ameliorated by insulin administration.