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Background information: Tubulointerstitial fibrosis is the end‐point of chronic kidney diseases. Tamoxifen, a selective oestrogen receptor (ER) modulator, attenuates renal fibrosis, by regulating the transforming growth factor (TGF)‐β/Smad signalling. Src and phosphoinositide 3‐kinase (PI3K)/Akt pathways play critical roles in the pathogenesis of renal fibrosis. However, the activation of the non‐canonical TGF‐β signalling in renal fibrosis after treatment with tamoxifen remains unclear. Renal fibrosis was induced by unilateral ureteral obstruction (UUO) in rats. Tamoxifen was orally administered after UUO. Additionally, HK‐2 cells were treated with tamoxifen in the presence or absence of TGF‐β1. The selective ER down‐regulator ICI and ER‐α silencing were used to confirm the involvement of ER‐α on the effect of tamoxifen on TGF‐β1‐stimulated fibrosis in HK‐2 cells. Results: Tamoxifen treatment ameliorated UUO‐induced renal fibrosis as shown by decreased expression of α‐smooth muscle actin (SMA), fibronectin and connective tissue growth factor (CTGF). The phosphorylation of Src, PI3K, Akt, mammalian target of rapamycin (mTOR) and p70S6K significantly decreased in UUO kidneys from tamoxifen‐treated animals. Tamoxifen dose‐dependently suppressed the TGF‐β1‐induced expression of α‐SMA and CTGF, and phosphorylation of Src, PI3K, Akt, mTOR and p70S6K in HK‐2 cells. These anti‐fibrotic effects were reversed by treatment with ICI and silencing of ER‐α. Moreover, inhibition of the PI3K/Akt and mTOR/p70S6K pathways was observed in HK‐2 cells co‐treated with PP1 (a Src kinase inhibitor) and tamoxifen. Conclusions: The anti‐fibrotic effects of tamoxifen are associated with the suppression of Src kinase function via ER‐α, followed by inhibition of the PI3K/Akt and mTOR/p70S6K signalling pathways. Significance: Our findings suggest that tamoxifen is a novel therapeutic option for the prevention and treatment of renal fibrosis. Research Article: Our results demonstrated that phosphorylation of Src kinase in the obstructive kidney medicates renal fibrosis by activation of PI3K/Akt and mTOR/p70S6K signalling pathway, and treatment of tamoxifen has anti‐fibrotic effect on renal fibrosis by suppressing these pathways. In addition, our in vitro results suggested that anti‐fibrotic effect and its downstream signalling pathway were attenuated by tamoxifen in an ER‐α‐dependent manner. However, at present, it remains difficult to determine whether tamoxifen acts as anti‐oestrogenic or oestrogenic effect in our study. [ABSTRACT FROM AUTHOR]

The association between arterial stiffness and decline in kidney function in patients with mild to moderate chronic kidney disease (CKD) is not well established. This study investigated whether pulse wave velocity (PWV) and pulse pressure (PP) are independently associated with glomerular filtration rate (GFR) and rapid decline in kidney function in early CKD. Carotid femoral PWV (cfPWV), brachial-ankle PWV (baPWV), and PP were measured in a cohort of 913 patients (mean age, 63±10 years; baseline estimated GFR, 84±18 mL/min/1.73 m2). Estimated GFR was measured at baseline and at follow-up. The renal outcome examined was rapid decline in kidney function (estimated GFR loss, >3 mL/min/1.73 m2 per year). The median follow-up duration was 3.2 years. Multivariable adjusted linear regression model indicated that arterial PWV (both cfPWV and baPWV) and PP increased as estimated GFR declined, but neither was associated with kidney function after adjustment for various covariates. Multivariable logistic regression analysis found that cfPWV and baPWV were not associated with rapid decline in kidney function (odds ratio [OR], 1.39, 95% confidence interval [CI], 0.41-4.65; OR, 2.51, 95% CI, 0.66-9.46, respectively), but PP was (OR, 1.22, 95% CI, 1.01-1.48; P=.045). Arterial stiffness assessed using cfPWV and baPWV was not correlated with lower estimated GFR and rapid decline in kidney function after adjustment for various confounders. Thus, PP is an independent risk factor for rapid decline in kidney function in populations with relatively preserved kidney function (estimated GFR ≥30 mL/min/1.73 m2). [ABSTRACT FROM AUTHOR]

The present study aimed to examine whether there is an altered regulation of local hormonal systems in the kidney following the treatment of glycyrrhizic acid (GA), the active ingredient in licorice. Male Sprague-Dawley rats were treated with GA for 3 weeks. The expression of mineralocorticoid receptor (MR) was determined in the kidney by immunoblotting and real-time polymerase chain reaction (PCR). The protein expression of endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS) was determined. The expression of atrial natriuretic peptide (ANP), natriuretic peptide receptor (NPR)-A and NPR-C was determined by real-time PCR. The activity of guanylyl cyclase was determined by the amount of cGMP generated in responses to sodium nitroprusside (SNP) or ANP. Following the GA treatment, systolic blood pressure was increased. The mRNA and protein expressions of MR were increased in the kidney. The protein expression of eNOS and iNOS was also increased. The expression of ANP mRNA was increased although that of NPR-A and NPR-C mRNA was not changed. The cGMP production provoked by either SNP or ANP was not changed. The increased expression of MR may contribute to GA-induced hypertension. The enhanced expression of NOS and ANP may play a compensatory role in GA-induced hypertension. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

1. The effects of volume depletion and NaHCO3 loading on the expression of Na+/H+ exchanger isoform 3 (NHE3), Na+ : cotransporter type 1 (NBC1) and neuronal (n) and inducible (i) isoforms of nitric oxide synthase (NOS) were determined in rat kidney. 2. Adult male Sprague-Dawley rats were used. Rats were divided into four groups: (i) euvolaemic (EC); (ii) hypovolaemic (HC); (iii) euvolaemia with NaHCO3 loading (EB); and (iv) hypovolaemia with NaHCO3 loading (HB). The expression of NHE3, NBC1, nNOS and iNOS proteins was determined in the cortex of the kidney by immunoblotting and immunohistochemistry. Tissue content of nitric oxide (NO) metabolites (NOx) were also determined in the cortex using a colourimetric assay. 3. Compared with the EC group, the expression of NHE3 and NBC1 was increased in the HC group and decreased in the EB group. Comparing the EB and HB groups, the expression of NHE3 and NBC1 was higher in the latter group. The expression of NHE3 was decreased and that of NBC1 was increased in the HB group compared with the HC group. The NOx content and nNOS expression were decreased in the hypovolaemic (HC) and NaHCO3-loaded (EB and HB) rats. Moreover, the expression of iNOS was decreased in the HB group compared with the other groups. 4. An altered volume status and NaHCO3 loading may affect the regulation of NHE3 and NBC1 in the kidney and the endogenous NO system may play a role in the observed effects. [ABSTRACT FROM AUTHOR]

1. Effects of non-steroidal anti-inflammatory drugs on the local atrial natriuretic peptide (ANP) and nitric oxide (NO) systems in the kidney were investigated. 2. Male Sprague-Dawley rats were treated with indomethacin (5 mg/kg, every 12 h, i.p.) for 2 days. The expression of ANP and natriuretic peptide receptor-A (NPR-A) mRNA was determined in the kidney, as was that of endothelial NO synthase (NOS) proteins. Particulate and soluble guanylyl cyclase activities were determined separately. 3. Following treatment with indomethacin, urinary sodium excretion decreased significantly. Although the renal expression of ANP was not changed significantly, that of NPR-A decreased significantly. The expression of NOS increased significantly. Particulate guanylyl cyclase activity was decreased, whereas the activity of soluble guanylyl cyclase was increased. The catalytic activity of Na+/K+-ATPase was increased, with no significant changes in its expression. The expression of the type 3 Na/H exchanger and Na–K−2CL cotransporters increased significantly. 4. The indomethacin-induced decrease in urinary sodium excretion may be attributed, at least in part, to decreased activity of the local ANP/cGMP system. The increased activity of the NO/cGMP system may be a compensatory response to the diminished activity of the prostaglandin system. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding a case study of a 58-year-old man with generalized oedema diagnosed with Waldenström macroglobulinaemia which presents perirenal mass with nephrotic syndrome caused by focal segmental glomerulosclerosis (FSGS).

The article describes the case of a male patient undergoing continuous peritoneal dialysis (CAPD) with candida guilliermondii. It discusses the symptoms experienced by the patient, confirmation of candida guilliermondii by 16s ribosomal RNA sequencing, the association of fungal peritonitis with mortality and catheter loss in patients undergoing CAPD.

Background Hypertension among young adults is common. However, the effect of isolated systolic hypertension (ISH), isolated diastolic hypertension (IDH), or systolic and diastolic hypertension (SDH) among young adults on chronic kidney disease (CKD) development is unknown. Methods and Results From a nationwide health screening database, we included 3 030 884 participants aged 20 to 39 years who were not taking antihypertensives at baseline examination in 2009 to 2010. Participants were categorized as having normal blood pressure (BP), elevated BP, stage 1 IDH, stage 1 ISH, stage 1 SDH, stage 2 IDH, stage 2 ISH, and stage 2 SDH. The primary outcome was incident CKD. A total of 5853 (0.19%) CKD events occurred. With normal BP as the reference, multivariable-adjusted hazard ratios (HRs) (95% CIs) for CKD were 1.14 (95% CI, 1.04-1.26), elevated BP; 1.19 (95% CI, 1.10-1.28), stage 1 IDH; 1.24 (95% CI, 1.08-1.42), stage 1 ISH; 1.39 (95% CI, 1.28-1.51), stage 1 SDH; 1.88 (95% CI, 1.63-2.16), stage 2 IDH; 1.84 (95% CI, 1.54-2.19), stage 2 ISH; 2.70 (95% CI, 2.44-2.98), stage 2 SDH. The HRs for CKD were attenuated in the patients who were antihypertensive and began medication within 1 year of medical checkup than in those without antihypertensives. Conclusions Among Korean young adults, those with elevated BP, stage 1 IDH, stage 1 ISH, stage 1 SDH, stage 2 IDH, stage 2 ISH, and stage 2 SDH were associated with a higher CKD risk than those with normal BP. The CKD risk in ISH and IDH groups was similar but lower than that in the SDH group. Antihypertensives attenuated the risk of CKD in young adults with hypertension.

1. The effects of volume depletion and NaHCO(3) loading on the expression of Na(+)/H(+) exchanger isoform 3 (NHE3), Na(+) : HCO(3)(-) cotransporter type 1 (NBC1) and neuronal (n) and inducible (i) isoforms of nitric oxide synthase (NOS) were determined in rat kidney. 2. Adult male Sprague-Dawley rats were used. Rats were divided into four groups: (i) euvolaemic (EC); (ii) hypovolaemic (HC); (iii) euvolaemia with NaHCO(3) loading (EB); and (iv) hypovolaemia with NaHCO(3) loading (HB). The expression of NHE3, NBC1, nNOS and iNOS proteins was determined in the cortex of the kidney by immunoblotting and immunohistochemistry. Tissue content of nitric oxide (NO) metabolites (NO(x)) were also determined in the cortex using a colourimetric assay. 3. Compared with the EC group, the expression of NHE3 and NBC1 was increased in the HC group and decreased in the EB group. Comparing the EB and HB groups, the expression of NHE3 and NBC1 was higher in the latter group. The expression of NHE3 was decreased and that of NBC1 was increased in the HB group compared with the HC group. The NO(x) content and nNOS expression were decreased in the hypovolaemic (HC) and NaHCO(3)-loaded (EB and HB) rats. Moreover, the expression of iNOS was decreased in the HB group compared with the other groups. 4. An altered volume status and NaHCO(3) loading may affect the regulation of NHE3 and NBC1 in the kidney and the endogenous NO system may play a role in the observed effects.