Association of polypharmacy with incidence of CKD: a retrospective cohort study.

BACKGROUND: Polypharmacy is common in patients with chronic kidney disease (CKD) and is associated with a decline in kidney function. However, its impact on patients without CKD has not been adequately elucidated. Therefore, we aimed to investigate the association between polypharmacy and the incidence of CKD. METHODS: We conducted retrospective cohort study using 1221 participants who were enrolled in the Fukushima Cohort Study with one or more risk factors of CKD, an estimated glomerular filtration rate (eGFR) of ≥ 60 mL/min/1.73 m2, and without proteinuria. Participants were categorized into three groups based on the number of medications: non-polypharmacy, 0-4 medications; polypharmacy, 5-9 medications; and hyper-polypharmacy, ≥ 10 medications. RESULTS: The median age was 62 years, 49% were men, the median eGFR was 75.4 ml/min/1.73 m2, and the median number of medications was 5. Polypharmacy and hyper-polypharmacy were noted in 506 (41%) and 250 (20%) participants, respectively. During follow-up, 288 participants developed CKD and 67 cardiovascular events were observed. Compared to the non-polypharmacy group, the hyper-polypharmacy group had a higher risk of CKD and cardiovascular events. The adjusted hazard ratios were 1.41 (95% CI1.01-1.99) and 2.24 (95% CI1.05-4.78) for the incidence of CKD and cardiovascular events, respectively. Sensitivity analyses yielded similar findings for the restricted cubic spline function models. CONCLUSIONS: Hyper-polypharmacy is associated with a higher risk of CKD and cardiovascular events.

Hematological parameters of anemia and prognosis of non-dialysis-dependent chronic kidney disease: the Fukushima CKD cohort study.

BACKGROUND: Mean corpuscular volume (MCV) and red cell distribution width (RDW), as well hemoglobin, are reported to be associated with mortality in various populations. However, associations between such hematological parameters and adverse outcomes in patients with CKD have not been sufficiently elucidated. METHODS: A total of 1,320 participants enrolled in the Fukushima CKD Cohort Study were examined to investigate associations between hematological parameters of anemia (MCV and RDW) and adverse outcomes, such as ESKD, all-cause death, and cardiovascular events, in patients with non-dialysis-dependent CKD. Baseline hematological parameters were grouped as follows: hemoglobin into 3 categories (< 11.0 g/dL, 11.0 ≤ - < 13.0 g/dL [reference], and ≥ 13.0 g/dL); MCV into 5 categories (< 90 fL, ≥ 90 - < 94 fL [reference], ≥ 94 - < 98 fL, ≥ 98 - < 102 fL, and ≥ 102 fL); and RDW into 2 categories (< 13.6% [reference] vs ≥ 13.6%). RESULTS: During the median observational period of 4.7 years, 120 patients developed ESKD, 160 developed cardiovascular events, and 122 died. Hemoglobin < 11 g/dL (hazard ratio [HR] 1.56, 95% confidence interval [CI], 1.00-2.42), MCV < 90 fL (HR 2.01, 95% CI 1.14-3.54), and RDW ≥ 13.6% (HR 1.57, 95% CI 1.01-2.42) were significantly associated with higher risks of ESKD. Hemoglobin < 11 g/dL, MCV ≥ 98 fL, and RDW ≥ 13.6% were significantly associated with higher risks of all-cause death. No significant associations between hematological parameters and risk of cardiovascular events were confirmed. CONCLUSION: In patients with non-dialysis-dependent CKD, MCV, RDW, and hemoglobin were associated with increased risks of ESKD and all-cause mortality.

Association between serum potassium levels and adverse outcomes in chronic kidney disease: the Fukushima CKD cohort study.

BACKGROUND: Serum potassium disorders, commonly observed in chronic kidney disease (CKD), are reportedly associated with higher mortality, but their impact on renal outcomes is still controversial. METHODS: The present study used the longitudinal data of the Fukushima CKD cohort study to investigate the relationships between hypokalemia and hyperkalemia and adverse outcomes such as renal outcomes and all-cause mortality in Japanese patients with non-dialysis-dependent CKD. The study involved 1330 CKD patients followed-up for 2.8 years. The primary endpoint of the present study was a kidney event, defined as a combination of doubling of baseline serum creatinine and end-stage kidney disease. RESULTS: Hyperkalemia (≥ 5.0 mmol/L) was noted in 10.6% and hypokalemia (< 4.0 mmol/L) in 16.4% of the study population. Significant U-shaped associations were observed between potassium levels and both kidney events and all-cause mortality on univariate Cox regression analyses. After adjustment for covariates, both hypokalemia and hyperkalemia were significantly associated with an increased risk of kidney events, with the lowest risk at a serum potassium of 4.0-4.4 mmol/L. Compared with a reference level of 4.0-4.4 mmol/L, the adjusted hazard ratio for kidney events was 2.49 (1.33-4.66) for serum potassium < 4.0 mmol/L, 1.72 (1.00-2.96) for 4.5-4.9 mmol/L, and 2.16 (1.15-4.06) for ≥ 5.0 mmol/L. There was no significant association between serum potassium levels and mortality after multivariate adjustment. CONCLUSION: Hypokalemia and hyperkalemia were associated with an increased risk of CKD progression, but not with mortality in Japanese patients with non-dialysis-dependent CKD.

Changes in serum and intracardiac fibroblast growth factor 23 during the progression of left ventricular hypertrophy in hypertensive model rats.

BACKGROUND: Recent clinical studies have demonstrated that serum fibroblast growth factor 23 (FGF23) levels have a significant association with left ventricular hypertrophy (LVH). Although LVH is commonly seen in hypertensive patients, the association between FGF23, hypertension, and LVH remains unclear. We aimed to examine the changes in serum and intracardiac FGF23 during the progression of hypertension using spontaneously hypertensive rats (SHR). METHODS: Male SHR comprised the experimental group (HT group) and Wistar Kyoto rats served as controls. At 10 weeks, urinary and blood biochemical analyses and blood pressure measurements were performed for both the groups. At 18 weeks, the rats were sacrificed: urinary and blood biochemical analyses and real-time PCR were performed. RESULTS: At 18 weeks, the relative heart weight and serum N-terminal pro-brain natriuretic peptide and aldosterone levels were significantly greater in the HT group. Serum calcium and phosphate levels were significantly lower, while serum FGF23 levels were significantly higher in the HT group compared to the control group. Further analyses showed that the mRNA expression of FGF23 in the heart was significantly increased in the HT group compared to the control group. Both serum FGF23 levels and intracardiac mRNA expression of FGF23 showed significant correlation with the relative heart weight. CONCLUSIONS: During LVH progression, serum and intracardiac FGF23 increased in hypertension. Although it is unclear whether the change in FGF23 is the cause or result of LVH, the interaction between FGF23 and aldosterone may be associated with the development of LVH in hypertension.

Interactions of HP1 Bound to H3K9me3 Dinucleosome by Molecular Simulations and Biochemical Assays.

Heterochromatin protein 1 (HP1), associated with heterochromatin formation, recognizes an epigenetically repressive marker, trimethylated lysine 9 in histone H3 (H3K9me3), and generally contributes to long-term silencing. How HP1 induces heterochromatin is not fully understood. Recent experiments suggested that not one, but two nucleosomes provide a platform for this recognition. Integrating previous and new biochemical assays with computational modeling, we provide near-atomic structural models for HP1 binding to the dinucleosomes. We found that the dimeric HP1α tends to bind two H3K9me3s that are in adjacent nucleosomes, thus bridging two nucleosomes. We identified, to our knowledge, a novel DNA binding motif in the hinge region that is specific to HP1α and is essential for recognizing the H3K9me3 sites of two nucleosomes. An HP1 isoform, HP1γ, does not easily bridge two nucleosomes in extended conformations because of the absence of the above binding motif and its shorter hinge region. We propose a molecular mechanism for chromatin structural changes caused by HP1.

Phosphorylation of Ser-525 in ßPix impairs Nox1-activating ability in Caco-2 cells.

ßPix activates Nox1, an O2--generating NADPH oxidase, through Rac activation. In this study, we found that S525E mutation of ßPix eliminated its Nox1-activating ability in transfected Caco-2 cells. Unexpectedly, affinity for Rac was not diminished but rather enhanced by S525E mutation, and guanine nucleotide exchange factor (GEF) activity was not altered. The N-terminal fragment (amino acids 1-400) showed similar Rac-binding and GEF activity to wild-type ßPix. In contrast, the C-terminal fragment (amino acids 408-646) had higher Rac-binding activity, particularly for Rac-GTP, than wild-type ßPix, and showed no GEF activity. These data suggest that a second Rac-binding site within the C-terminal region is opened by phosphorylation of Ser-525. The site may bind not only Rac-GDP but also Rac-GTP released from the N-terminal catalytic region, which interrupts Rac-GTP translocation to the membrane where Nox1 resides. If one considers that S340E mutation enhances Nox1 activation (Kaito et al., 2014), the present study suggests that ßPix can also play an inhibitory role in O2- production, depending on the sites of phosphorylation.

Relationship Between Type of Hypertension and Renal Arteriolosclerosis in Chronic Glomerular Disease.

BACKGROUND/AIMS: Hypertension (HT) is a common complication in patients with chronic kidney disease (CKD). However, the relationship between circadian rhythm disorder of blood pressure (BP) and intra-renal damage remains unclear. METHODS: Ninety patients with chronic glomerular disease (CGD) were included in the present study. On the basis of the clinic BP (CBP) and 24 h-ambulatory BP (ABP) measurements, the patients were divided into the following groups; normotension (NT), white coat HT (WHT), masked HT (MHT), and sustained HT (SHT). For renal histopathological assessment, we evaluated each biopsy specimen for sclerotic glomeruli (SG), interstitial fibrosis (IF), intimal thickening of intra-lobular arteries (ILA), and arteriolar hyalinosis (AH). RESULTS: The prevalence of NT, WHT, MHT and SHT was 60.0%, 3.3%, 23.3%, and 13.4%, respectively. Compared with circadian BP pattern, all-day HT was most prevalent in the SHT group, whereas nighttime HT was most prevalent in the MHT group. The results of histological analysis showed that the SHT group had more severe SG and IF and the MHT group had more severe IF compared to the NT group. As for renal arteriolosclerosis, the MHT and SHT groups had more severe AH compared with the NT group, whereas ILA was comparable among all four groups. Furthermore, multivariate analysis revealed that ILA was significantly correlated only with age, whereas AH was significantly correlated with age and HT based on ABP, but not HT based on CBP. CONCLUSIONS: Our findings suggest that renal AH was severe not only in the SHT group, but also in the MHT group. Careful ABP monitoring should be recommended in patients with CGD.

Riser pattern is a predictor of kidney mortality among patients with chronic kidney disease.

BACKGROUND: Hypertension is a crucial risk factor for cardiovascular death and loss of residual kidney function. Absence of the nocturnal decline in blood pressure (BP) predicts cardiovascular events and poor prognosis. However, characteristics of hypertension in moderate-to-severe chronic kidney disease (CKD) have not been fully evaluated. We aimed to assess the circadian variation of BP and kidney survival in CKD patients. METHODS: Patients who were examined by 24-h ambulatory BP monitoring (ABPM) and estimated glomerular filtration rate (eGFR), <45 ml/min/1.73 m(2), were enrolled in the study. The impacts of BP circadian rhythm and brain natriuretic peptide (BNP) on kidney survival were evaluated. RESULTS: A total of 124 patients were enrolled. The average age was 64 ± 14 years, 57% were male, and 43% had diabetes. Forty-five percent of patients had a non-dipper pattern, 35% had a riser pattern, 19% had a dipper pattern, and 1% had an extreme-dipper pattern. The prevalence of diabetes and plasma BNP levels was higher and eGFR was lower in the riser-pattern group than in the non-riser-pattern group. Kidney survival rates were significantly worse in the riser-pattern group than in the non-riser-pattern group (p < 0.05). Moreover, among riser and non-riser pattern groups divided by BNP levels, the riser group with higher BNP level showed the worst kidney survival (p < 0.05). CONCLUSION: The riser pattern is frequently associated with several conditions at higher risk for kidney survival. Patients with a rising pattern and higher BNP levels have a worse kidney prognosis.

Mesenchymal stem cells cancel azoxymethane-induced tumor initiation.

The role of mesenchymal stem cells (MSCs) in tumorigenesis remains controversial. Therefore, our goal was to determine whether exogenous MSCs possess intrinsic antineoplastic or proneoplastic properties in azoxymethane (AOM)-induced carcinogenesis. Three in vivo models were studied: an AOM/dextran sulfate sodium colitis-associated carcinoma model, an aberrant crypt foci model, and a model to assess the acute apoptotic response of a genotoxic carcinogen (AARGC). We also performed in vitro coculture experiments. As a result, we found that MSCs partially canceled AOM-induced tumor initiation but not tumor promotion. Moreover, MSCs inhibited the AARGC in colonic epithelial cells because of the removal of O(6)-methylguanine (O(6) MeG) adducts through O(6) MeG-DNA methyltransferase activation. Furthermore, MSCs broadly affected the cell-cycle machinery, potentially leading to G1 arrest in vivo. Coculture of IEC-6 rat intestinal cells with MSCs not only arrested the cell cycle at the G1 phase, but also induced apoptosis. The anti-carcinogenetic properties of MSCs in vitro required transforming growth factor (TGF)-ß signaling because such properties were completely abrogated by absorption of TGF-ß under indirect coculture conditions. MSCs inhibited AOM-induced tumor initiation by preventing the initiating cells from sustaining DNA insults and subsequently inducing G1 arrest in the initiated cells that escaped from the AARGC. Furthermore, tumor initiation perturbed by MSCs might potentially dysregulate WNT and TGF-ß-Smad signaling pathways in subsequent tumorigenesis. Obtaining a better understanding of MSC functions in colon carcinogenesis is essential before commencing the broader clinical application of promising MSC-based therapies for cancer-prone patients with inflammatory bowel disease.

Adult-onset Still's Disease with Acute Kidney Injury Requiring Hemodialysis: A Case Report and Literature Review.

Adult-onset Still's disease (AOSD) is characterized by high spiking fever, evanescent rash, and arthritis. However, AOSD rarely presents with severe acute kidney injury (AKI). We herein present the case of a 56-year-old woman with new-onset AOSD who rapidly developed AKI. A physical examination and laboratory data revealed spiking fever, evanescent rash, thrombocytopenia, hyperferritinemia, and azotemia. The patient was diagnosed with AOSD complicated by AKI and macrophage activation syndrome. Treatment with high-dose steroids, hemodialysis, and plasma exchange successfully resolved her AKI. In this report, we review previously published reports on AOSD accompanied by AKI and discuss this rare complication in AOSD.

Association between Serum Inorganic Phosphorus Levels and Adverse Outcomes in Chronic Kidney Disease: The Fukushima CKD Cohort Study.

Objective Although an association between serum inorganic phosphorus levels and a poor prognosis has been noted in dialysis patients, these associations have been insufficiently reported in non-dialysis-dependent chronic kidney disease (NDD-CKD) patients. This study attempted to determine the association between serum inorganic phosphorus levels and adverse outcomes in Japanese NDD-CKD patients. Methods We investigated the relationships between serum inorganic phosphorus levels and adverse outcomes, such as kidney events, cardiovascular events, and all-cause death, in Japanese NDD-CKD patients using longitudinal data from the Fukushima CKD Cohort Study with a median follow-up period of 2.8 years. The study evaluated 822 patients with NDD-CKD enrolled between June 2012 and July 2014. A kidney event was defined as a combination of doubling of the baseline serum creatinine or end-stage renal disease. Cox regression was performed to analyze the relationships of the quartile of the serum inorganic phosphorus with kidney events, cardiovascular events, and all-cause death. Results The frequency of kidney events per 1,000 person-years exhibited a U-shaped distribution based on serum inorganic phosphorus levels, with these levels not significantly associated with an increased risk of cardiovascular events and all-cause death. A multivariable Cox regression analysis showed an increased risk of kidney events for the highest quartile of the serum inorganic phosphorus levels (≥3.7 mg/dL) versus the second quartile (2.9-3.2 mg/dL, hazard ratio, 3.30; 95% confidence interval, 1.50-7.28; p=0.003). There were no significant associations between the serum calcium levels and adverse outcomes. Conclusion Serum inorganic phosphorus levels were associated with an increased risk of CKD progression in Japanese NDD-CKD patients.

An alternative predictor of eye irritation that utilizes potential parameters of the human corneal epithelium model calculated based on Hansen solubility parameters.

Eye irritation predictions are very important in the development of cosmetics and pharmaceuticals. For animal protection, alternative tests are being developed to replace the Draize test, which involves the use of rabbits to test eye irritation. The Vitrigel-eye irritancy test (Vitrigel-EIT), is one such alternative. As a preliminary study, we evaluated if Hansen solubility parameter (HSP) values can be used to predict Vitrigel-EIT results. An Hansen sphere was created based on the HSP values and Vitrigel-EIT results from 61 substances. Substances inside and outside of the sphere were designated as dangerous and safe substances, respectively. The safety of each test substance was predicted by comparing the center point (Ro) of the sphere with the relative energy difference, i.e., the ratio of each test substance (Ra). The accuracy, false negativity, and false positivity of the "irritant" and "nonirritant" designations, as determined by the Vitrigel-EIT results and Hansen sphere, were 91.8% (56/61), 2.3% (1/43), and 22.2% (4/18), respectively. These results indicated that HSP values can be used to predict Vitrigel-EIT results with high reproducibility, and thus are useful for evaluating the safety of substances.

Highly accurate predictor of eye irritation utilizing potential parameters of a reconstructed human cornea epithelium model calculated based on Hansen solubility parameters.

Concerns regarding animal welfare have led to the need for alternatives to animal eye irritation tests. The reconstructed human cornea-like epithelium (RhCE) test is described in the OECD TG 492 as an alternative to animal eye irritation tests. However, the accuracy and labor investment of this method can be improved if the results can be predicted before the experiment. In this study, we evaluated whether Hansen solubility parameter (HSP) values can be used to predict the results of RhCE method using the LabCyte CORNEA-MODEL for 65 test substances. We found that HSP values can predict the RhCE method with high correlation (accuracy 84.6% (55/65), false-negative rate of 16.2% (7/43), and false-positive rate of 13.6% (3/22). These results indicate that HSP values can be used to predict the results RhCE method using LabCyte CORNEA-MODEL with high reproducibility, and thus are useful for evaluating the safety of substances.

Xanthine oxidase inhibitors are associated with reduced risk of cardiovascular disease.

As previous studies have reported finding an association between hyperuricemia and the development of cardiovascular and chronic kidney disease, hyperuricemia is thought to be an independent risk factor for hypertension and diabetic mellitus. However, we have not been able to determine whether the use of xanthine oxidase inhibitors can reduce cardiovascular disease. The present study used the longitudinal data of the Fukushima Cohort Study to investigate the relationship between the use of xanthine oxidase inhibitors and cardiovascular events in patients with cardiovascular risks. During the 3-year period between 2012 and 2014, a total of 2724 subjects were enrolled in the study and followed. A total of 2501 subjects had hypertension, diabetic mellitus, dyslipidemia, or chronic kidney disease, and were identified as having cardiovascular risks. The effects of xanthine oxidase inhibitor use on the development of cardiovascular events was evaluated in these patients using a time to event analysis. During the observational periods (median 2.7 years), the incidence of cardiovascular events was 20.7 in subjects with xanthine oxidase inhibitor and 11.2 (/1000 person-years, respectively) in those without. Although a univariate Cox regression analysis showed that the risk of cardiovascular events was significantly higher in subjects administered xanthine oxidase inhibitors (HR = 1.87, 95% CI 1.19-2.94, p = 0.007), the risk was significantly lower in subjects administered a xanthine oxidase inhibitor after adjustment for covariates (HR = 0.48, 95% CI 0.26-0.91; p = 0.024) compared to those without. Xanthine oxidase inhibitor use was associated with reduced risk of cardiovascular disease in patients with cardiovascular risk factors.

Association of Polypharmacy with Kidney Disease Progression in Adults with CKD.

BACKGROUND AND OBJECTIVE: Polypharmacy is common in patients with CKD and reportedly associated with adverse outcomes. However, its effect on kidney outcomes among patients with CKD has not been adequately elucidated. Hence, this investigation was aimed at exploring the association between polypharmacy and kidney failure requiring KRT. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: We retrospectively examined 1117 participants (median age, 66 years; 56% male; median eGFR, 48 ml/min per 1.73 m2) enrolled in the Fukushima CKD Cohort Study to investigate the association between the number of prescribed medications and adverse outcomes such as kidney failure, all-cause mortality, and cardiovascular events in Japanese patients with nondialysis-dependent CKD. Polypharmacy and hyperpolypharmacy were defined as the regular use of 5-9 and ≥10 medications per day, respectively. RESULTS: The median number of medications was eight; the prevalence of polypharmacy and hyperpolypharmacy was each 38%. During the observation period (median, 4.8 years), 120 developed kidney failure, 153 developed cardiovascular events, and 109 died. Compared with the use of fewer than five medications, adjusted hazard ratios (95% confidence intervals) associated with polypharmacy and hyperpolypharmacy were 2.28 (1.00 to 5.21) and 2.83 (1.21 to 6.66) for kidney failure, 1.60 (0.85 to 3.04) and 3.02 (1.59 to 5.74) for cardiovascular events, and 1.25 (0.62 to 2.53) and 2.80 (1.41 to 5.54) for all-cause mortality. CONCLUSIONS: The use of a high number of medications was associated with a high risk of kidney failure, cardiovascular events, and all-cause mortality in Japanese patients with nondialysis-dependent CKD under nephrology care.

Influence of oxidative stress on vascular calcification in the setting of coexisting chronic kidney disease and diabetes mellitus.

Vascular calcification (VC) is a common complication in patients with chronic kidney disease (CKD). Particularly, CKD patients with diabetes mellitus (DM) develop severe VC. Specific mechanisms of VC remain unclear; this study aimed to investigate them in the context of coexisting CKD and DM, mainly regarding oxidative stress. Sprague Dawley rats were randomly divided into six groups as follows: control rats (Control), 5/6 nephrectomized rats (CKD), streptozotocin-injected rats (DM), 5/6 nephrectomized and streptozotocin-injected rats (CKD + DM), CKD + DM rats treated with insulin (CKD + DM + INS), and CKD + DM rats treated with antioxidant apocynin (CKD + DM + APO). At 18 weeks old, the rats were sacrificed for analysis. Compared to the control, DM and CKD groups, calcification of aortas significantly increased in the CKD + DM group. Oxidative stress and osteoblast differentiation-related markers considerably increased in the CKD + DM group compared with the other groups. Moreover, apocynin considerably reduced oxidative stress, osteoblast differentiation-related markers, and aortic calcification despite high blood glucose levels. Our data indicate that coexisting CKD and DM hasten VC primarily through an increase in oxidative stress; anti-oxidative therapy may prevent the VC progression.

3D multiscale-imaging of processing-induced defects formed during sintering of hierarchical powder packings.

The characterization of the processing-induced defects is an essential step for developing defect-free processing, which is important to the assurance of structural reliability of brittle ceramics. The multiscale X-ray computed tomography, consisting of micro-CT as a wide-field and low-resolution system and nano-CT as a narrow-field and high-resolution system, is suitable for observing crack-like defects with small length and with very small crack opening displacement. Here we applied this powerful imaging tool in order to reveal the complicated three-dimensional morphology of defects evolved during sintering of alumina. The hierarchical packing structure of granules was the origin of several types of strength-limiting defects, which could not be eliminated due to the differential sintering of heterogeneous microstructures. This imaging technique of internal defects provides a link between the processing and the fracture strength for the development of structural materials.

One-Year Impact of Kidney Transplantation on Cardiac Abnormalities and Blood Pressure in Hemodialysis Patients.

Cardiac abnormalities, including left ventricular hypertrophy and systolic dysfunction, are frequently observed among patients with CKD, including kidney transplant recipients; they are closely linked to cardiovascular disease and mortality. Although several studies have been performed for elucidating changes and mechanisms of cardiac abnormalities after kidney transplantation, details remain unclear. This study included 43 consecutive patients who underwent HD and received kidney transplantation between 2008 and 2012 at our institution. All subjects underwent echocardiography before and 1 year after kidney transplantation. One year after kidney transplantation, left ventricular mass index, cardiac chamber sizes, BP, and the number of antihypertensive agents were reduced. Although the percentage of patients with concentric hypertrophy did not change, the percentage of those with eccentric hypertrophy significantly decreased after kidney transplantation. Volume reduction due to the recovery of kidney function may be primarily attributed to the improvement of cardiac abnormalities, including left ventricular hypertrophy.

Newly Developed Rat Model of Chronic Kidney Disease-Mineral Bone Disorder.

AIM: Chronic kidney disease-mineral bone disorder (CKD-MBD) is associated with all-cause and cardiovascular morbidity and mortality in patients with CKD. Thus, elucidating its pathophysiological mechanisms is essential for improving the prognosis. We evaluated characteristics of CKD-MBD in a newly developed CKD rat model. METHODS: We used male Sprague-Dawley (SD) rats and spontaneously diabetic Torii (SDT) rats, which are used as models for nonobese type 2 diabetes. CKD was induced by 5/6 nephrectomy (Nx). At 10 weeks, the rats were classified into six groups and administered with a vehicle or a low- or high-dose paricalcitol thrice a week. At 20 weeks, the rats were sacrificed; blood and urinary biochemical analyses and histological analysis of the aorta were performed. RESULTS: At 20 weeks, hemoglobin A1c (HbA1c) levels, blood pressure, and renal function were not significantly different among the six groups. Serum calcium and phosphate levels tended to be higher in SDT-Nx rats than in SD-Nx rats. The urinary excretion of calcium and phosphate was significantly greater in SDT-Nx rats than in SD-Nx rats. After administering paricalcitol, serum parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23) levels were significantly higher in SDT-Nx rats than in SD-Nx rats. The degree of aortic calcification was significantly more severe and the aortic calcium content was significantly greater in SDT-Nx rats than in SD-Nx rats. CONCLUSIONS: We suggest that our new CKD rat model using SDT rats represents a useful CKD-MBD model, and this model was greatly influenced by paricalcitol administration. Further studies are needed to clarify the detailed mechanisms underlying this model.