A systematic review for prevention of cisplatin-induced nephrotoxicity using different hydration protocols and meta-analysis for magnesium hydrate supplementation.

BACKGROUND: Nephrotoxicity remains the most serious side effect of cisplatin therapy. Cisplatin-induced nephrotoxicity (CIN) limits the use of this drug and affects up to 20% of patients. Several possible interventions such as magnesium supplementation may prevent CIN. This study aimed to review different types of hydration protocols and we conducted a meta-analysis of magnesium supplementation to understand its effect in protecting against CIN. METHODS: A search of the PubMed, Embase, and Cochrane databases was performed. Trials were eligible if they enrolled patients who received cisplatin and different hydration protocols to prevent CIN. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the efficacy of different protocols. RESULTS: We initially identified 1113 different studies and included 33 of them which met the selection criteria. A meta-analysis of 11 retrospective studies that examined magnesium supplementation during hydration showed that this treatment provided significant protection against CIN (OR = 0.22, 95% CI = 0.14 to 0.35). CONCLUSION: There has been uncertainty regarding the best method to prevent CIN. Our results highlight the potentially protective effect of magnesium supplementation during hydration. This study is registered in PROSPERO, CRD42020212682.

Improvement of restless leg syndrome in maintenance hemodialysis patients with limb ischemic preconditioning: a single-center randomized controlled clinical trial.

OBJECTIVE: This study evaluated the efficacy and safety of limb ischemic preconditioning (LIPC) in treating restless leg syndrome (RLS) in maintenance hemodialysis (MHD) patients. METHODS: A total number of 45 patients participated in the study. They were randomly divided into LIPC group and control group. The LIPC was performed by inflating the limb ischemic preconditioning training device in the patient's thigh to 200 mmHg to create transient ischemia, whereas control group inflated the device to 20 mmHg. International Restless Legs Syndrome (IRLS), Clinical Global Impression Scale (CGI-S), and Medical Outputs Study Sleep Scale were employed to evaluate LIPC effectiveness. The primary endpoint was the 'rate of clinical improvement in RLS severity', defined as the percentage of patients who had an IRLS score decrease of ≥5 points in each group. RESULTS: After intervention, the rate of clinical improvement in RLS severity was 56.5% in the LIPC group and 13.6% in the control group (13 (56.5) vs 3 (13.6), p = 0.003). In addition, the LIPC group's IRLS, CGI-S scores, the sleep disturbance and somnolence scores showed a significant downward trend compared to the control group (-5.5 ± 5.3 vs - 1.0 ± 3.8, p = 0.002; -1.7 ± 1.2 vs - 0.5 ± 1.4, p = 0.003; -15.5 ± 17.8 vs 3.7 ± 12.0, p < 0.001; -9.9 ± 18.8 vs - 2.4 ± 8.6, p = 0.003). During the study, there were no serious adverse event in any of the patients. CONCLUSIONS: LIPC could be employed to effectively and safely alleviate the RLS symptoms in MHD patients.

Left ventricular hypertrophy, carotid atherosclerosis, and cognitive impairment in peritoneal dialysis patients.

BACKGROUND: Left ventricular hypertrophy (LVH) and carotid atherosclerosis (CAS) have been identified as factors associated with cognitive impairment (CI) but have not been studied in patients undergoing peritoneal dialysis (PD). This study investigated the relationship between LVH and CAS and cognitive function in patients undergoing PD. METHODS: In this single-center cross-sectional study, the clinically stable patients who were over 18 years of age and had undergone PD for at least 3 months were enrolled. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA), which included seven areas: visuospatial/executive function, naming, attention, language, abstraction, delayed recall, and orientation. LVH was defined as LVMI > 46.7 g/m2.7 in women and LVMI > 49.2 g/m2.7 in men. CAS was defined as carotid intima-media thickness ≥ 1.0 mm and/or the presence of plaque. RESULTS: A total of 207 patients undergoing PD were recruited, with an average age of 52.14 ± 14.93 years and a median PD duration of 8 months (5-19 months). The CI rate was 56%, and the prevalence of CAS was 53.6%. LVH occurred in 110 patients (53.1%). Patients in the LVH group tended to be older, and had a higher body mass index, a higher pulse pressure, a higher male proportion, a lower ejection fraction, a higher prevalence of cardiovascular disease and CI, and a lower MoCA scores.Multivariate logistic regression analysis was conducted to analyze the association between LVH and CI (OR, 10.087; 95% confidence interval, 2.966-34.307). And the association between LVH and CI was still supported after propensity matching scores. CAS was not significantly associated with CI. CONCLUSION: LVH is independently associated with CI in patients undergoing PD, while CAS is not significantly associated with CI.

The protective effect and mechanism of lentinan on acute kidney injury in septic rats.

BACKGROUND: This study aimed to investigate the protective effect and mechanism of lentinan (LNT) on acute kidney injury (AKI) in septic rats. METHODS: A total 72 male SD rats were randomly divided into 6 groups with 12 rats in each group. Except for the sham group, all groups, including the burn sepsis group (BS group), the positive drug control group (dexamethasone, 5 mg/kg, PC group), the LNT low-concentration group (LNT-L group) (50 mg/kg), the LNT medium-concentration group (LNT-M group) (100 mg/kg), and the LNT high-concentration group (LNT-H group) (200 mg/kg), were intraperitoneally injected with the same amount of normal saline 30 min before injury. The levels of serum interleukin (IL)-4, IL-6, IL-10, and tumor necrosis factor alpha (TNF-α); the indexes of blood urea nitrogen (BUN) and creatinine (Cr); and the protein expression levels of inducible nitric oxide synthase (iNOS), intercellular adhesion molecule 1 (ICAM-1), and nuclear factor-κB (NF-κB) in renal tissue were detected 24 hours after the model was established. RESULTS: Compared with the sham group, the BUN and Cr of the other groups were significantly higher, while those of the LNT group with different concentrations were significantly lower than those of the BS group (P<0.05). Compared with the sham group, the protein expression levels of NF-κB, iNOS, and ICAM-1 along with the levels of pro-inflammatory factors TNF-α and IL-6 in serum were significantly increased, while the levels of anti-inflammatory factors IL-4 and IL-10 were obviously lower in the BS group. Compared with the BS group, the protein expression levels of NF-κB, iNOS, and ICAM-1 along with the levels of pro-inflammatory factors TNF-α and IL-6 in serum were significantly decreased, while the levels of anti-inflammatory factors IL-4 and IL-10 were obviously increased in the LNT group with different concentrations.. CONCLUSIONS: LNT has a certain protective effect on AKI in septic rats, and its mechanism may involve inhibiting the activation of NF-κB, which suppresses the expression of proinflammatory factors in turn, thus promoting the release of anti-inflammatory factors.

miR-155-5p Implicates in the Pathogenesis of Renal Fibrosis via Targeting SOCS1 and SOCS6.

Renal fibrosis is associated with the reduction in the functional renal parenchyma and in most cases progresses to end-stage kidney failure, a devastating condition that requires lifelong dialysis or kidney transplantation. However, due to the extreme complexity in the pathogenesis of renal fibrosis and our limited knowledge, therapeutic options for renal fibrosis in the clinical setting are still scarce and often ineffective. Hence, further studies on the molecular mechanisms underlying renal fibrosis are compellingly needed. Multiple miRNAs have demonstrated to participate in kidney diseases in a TGF-ß dependent or independent manner, but there is very little known about miR-155-5p on renal fibrosis. In the present study, we firstly explored the expression level and functions of miR-155-5p in the setting of renal fibrosis. Our research revealed that miR-155-5p is highly expressed in kidney tissues from patients and unilateral ureteral obstruction (UUO) rat models, and miR-155-5p knockdown significantly blocks renal fibrosis both in vivo and in vitro. In mechanism, our data demonstrate that miR-155-5p promotes renal fibrosis by increasing the phosphorylated activation of STAT3 via targeting SOCS1/6. Altogether, our findings highlight a miR-155-5p/SOCS/STAT3 axis in the pathogenesis of renal fibrosis, which may provide promising therapeutic targets for clinical prevention of this disease.

Limb ischemic preconditioning ameliorates renal microcirculation through activation of PI3K/Akt/eNOS signaling pathway after acute kidney injury.

PURPOSE: Contrast-induced acute kidney injury (CI-AKI) resulting from administration of iodinated contrast media (CM) is the third leading cause of hospital-acquired acute kidney injury and is associated with substantial morbidity and mortality. Deteriorated renal microcirculation plays an important role in CI-AKI. Limb ischemic preconditioning (LIPC), where brief and non-injurious ischemia/reperfusion is applied to a limb prior to the administration of the contrast agent, is emerging as a promising strategy for CI-AKI prevention. However, it is not known whether the renal protection of LIPC against CI-AKI is mediated by regulation of renal microcirculation and the molecular mechanisms remain largely unknown. METHODS: In this study, we examined the renal cortical and medullary blood flow in a stable CI-AKI model using 5/6-nephrectomized (NE) rat. The LIPC and sham procedures were performed prior to the injection of CM. Furthermore, we analyzed renal medulla hypoxia using in vivo labeling of hypoxyprobe. Pharmacological inhibitions and western blotting were used to determine the underlying molecular mechanisms. RESULTS: In this study, we found LIPC significantly ameliorated CM-induced reduction of medullary blood flow and attenuated CM-induced hypoxia. PI3K inhibitor (wortmannin) treatment blocked the regulation of medullary blood flow and the attenuation of hypoxia of LIPC. Phosphorylation of Akt/eNOS was significantly decreased via wortmannin treatment compared with LIPC. Nitric oxide synthase-inhibitor [Nω-nitro-L-arginine methyl ester (L-NAME)] treatment abolished the above effects and decreased phosphorylation of eNOS, but not Akt. CONCLUSIONS: Collectively, the results demonstrate that LIPC ameliorates CM-induced renal vasocontraction and is mediated by activation of PI3K/Akt/eNOS signaling pathway.

Hydration Strategies for Preventing Contrast-Induced Acute Kidney Injury: A Systematic Review and Bayesian Network Meta-Analysis.

AIMS: Many previous studies have examined the effect of different hydration strategies on prevention of contrast-induced acute kidney injury (CI-AKI), but the optimal strategy is unknown. We performed a network meta-analysis (NWM) of these previous studies to identify the optimal strategy. METHODS AND RESULTS: Web of Science, PubMed, OVID Medline, and Cochrane Library were searched from their inception dates to September 30, 2018. Randomized controlled trials (RCTs) were selected based on strict inclusion criteria, and a Bayesian NWM was performed using WinBUGS V.1.4.3. We finally analyzed 60 eligible RCTs, which examined 21,293 patients and 2232 CI-AKI events. Compared to intravenous 0.9% sodium chloride (reference), intravenous sodium bicarbonate (OR [95% CI]: 0.74 [0.57, 0.93]), hemodynamic guided hydration (0.41 [0.18, 0.93]), and RenalGuard guided hydration (0.32 [0.14, 0.70]) significantly reduced the occurrence of CI-AKI. Oral hydration and intravenous 0.9% sodium chloride were each noninferior to no hydration in preventing CI-AKI. Intravenous 0.9% sodium chloride, sodium bicarbonate, and hemodynamic guided hydration were each noninferior to oral hydration in preventing CI-AKI. Based on surface under the cumulative ranking curve values, the RenalGuard system was best (0.974) and hemodynamic guided hydration was second best (0.849). CONCLUSION: There was substantial evidence to support the use of RenalGuard or hemodynamic guided hydration for preventing CI-AKI in high-risk patients, especially those with chronic kidney disease or cardiac dysfunction.

Remote Ischemic Preconditioning Protects Cisplatin-Induced Acute Kidney Injury through the PTEN/AKT Signaling Pathway.

Although cisplatin (Cis) is an effective chemotherapeutic agent in treatment of various cancers, its adverse effect of nephrotoxicity limits the clinical application. Remote ischemic preconditioning (RIPC) is a strategy to induce resistance in a target organ against the oxidative stress and injury by applying transient, brief episodes of ischemia. However, whether RIPC exerts protective effect on Cis-induced renal injury remains unclear. In this study, we showed that RIPC significantly alleviated the renal functional and histopathological damage of Cis-induced acute kidney injury (AKI) mice. Furthermore, RIPC substantially reversed the downregulation of miR-144 and upregulation of PTEN in renal tissues of Cis-induced AKI mice and alleviated tubular cell apoptosis via activating PTEN/AKT signaling. In mechanism, we demonstrated that miR-144 directly targets the 3'-UTR of PTEN mRNA, and then the elevation of miR-144 in RIPC activates PTEN/AKT signaling by downregulating PTEN expression to achieve its antiapoptosis effect. Collectively, our results indicate that RIPC may be a potential therapeutic strategy in Cis-induced AKI, and provide insights on the underlying molecular mechanisms of cisplatin's nephrotoxicity.

Plasma microRNA-186 and proteinuria in focal segmental glomerulosclerosis.

BACKGROUND: MicroRNAs (miRNAs) are stable in circulation, and their unique expression profiles can serve as fingerprints for various diseases. This study explored whether plasma miRNAs could be used as biomarkers to evaluate disease activity in patients with focal segmental glomerulosclerosis (FSGS). STUDY DESIGN: Retrospective and prospective cohorts. SETTING & PARTICIPANTS: 78 patients with FSGS with nephrotic proteinuria (protein excretion > 3.5g/24 h), 35 patients with FSGS in complete remission, 63 patients with membranous nephropathy, 59 patients with diabetic nephropathy, and 69 apparently healthy controls were recruited. Plasma samples from 51 other patients with FSGS with nephrotic proteinuria were collected prospectively before and after steroid treatment. PREDICTORS: Plasma miRNA concentration. OUTCOMES: Complete remission (protein excretion < 0.4g/24 h), or no response (sustained protein excretion > 3.5g/24 h after 8 weeks of steroid treatment). MEASUREMENTS: Quantitative reverse transcription-polymerase chain reaction analysis of plasma miRNAs. RESULTS: Increases in miR-125b, miR-186, and miR-193a-3p levels were identified in a pooled plasma sample of 9 patients with FSGS compared with that of 9 healthy controls and were confirmed with individual samples from patients with FSGS (n=32) and healthy controls (n=30). Areas under the receiver operating characteristic curves of miR-125b, miR-186, miR-193a-3p, and the 3 miRNAs in combination were 0.882, 0.789, 0.910, and 0.963, respectively. miR-125b and miR-186 concentrations were significantly lower in patients with FSGS in complete remission (n=35) than those with nephrotic proteinuria (n=37). In a prospective study, miR-125b and miR-186 levels declined markedly in patients with FSGS with complete remission (n=29), but not those with no response (n=22), after steroid treatment. Plasma miR-125b and miR-186 levels were not elevated in patients with membranous nephropathy (n=63) and diabetic nephropathy (n=59) regardless of degree of proteinuria. Last, plasma miR-186, but not miR-125b, level was correlated with degree of proteinuria in patients with FSGS (151 samples). LIMITATIONS: Relatively small cohort size. CONCLUSIONS: Plasma miR-186 may be a biomarker for FSGS with nephrotic proteinuria.

Evaluation of microRNAs miR-196a, miR-30a-5P, and miR-490 as biomarkers of disease activity among patients with FSGS.

BACKGROUND AND OBJECTIVES: This study aimed to identify urinary microRNAs (miRNAs) as biomarkers for FSGS disease activity. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Candidate urinary miRNAs were identified in pooled urine samples from patients with active FSGS (FSGS-A) and FSGS in remission (FSGS-CR), and were then validated using individual samples. Their levels were compared both under different treatment responses in a prospective study of FSGS and in patients with different membranous nephropathy (MN) and diabetic nephropathy (DN) disease activity. The prediction of these miRNAs for treatment responses was further analyzed in both retrospective and prospective cohorts of patients with FSGS. RESULTS: All 54 miRNAs were included as candidate biomarkers, including those with high levels in patients with FSGS-A (n=9) under the TaqMan Low Density Array as well as those with conserved expression in kidneys and involved in immune response. TaqMan probe-based quantitative RT-PCR confirmed the higher levels of four miRNAs in patients with FSGS-A in two independent cohorts (n=18 and n=80). Urinary miR-196a, miR-30a-5p, and miR-490 discriminated FSGS-A from FSGS-CR, with an area under the curve of ≥ 0.80. After steroid treatment, their levels were lower in steroid-responsive patients with FSGS (all P<0.001), but were unchanged in steroid-resistant patients. The levels of miRNAs were similar between active MN and MN in remission as well as active DN and incipient DN (all P>0.05). Urinary miR-30a-5p marginally predicted the response to steroid treatment in patients with FSGS-A, with an area under the curve of 0.63 (P=0.03). CONCLUSIONS: The levels of urinary miR-196a, miR-30a-5p, and miR-490 are associated with FSGS disease activity.

Downregulation of microRNA-30 facilitates podocyte injury and is prevented by glucocorticoids.

MicroRNAs (miRNAs) are essential for podocyte homeostasis, and the miR-30 family may be responsible for this action. However, the exact roles and clinical relevance of miR-30s remain unknown. In this study, we examined the expression of the miR-30 family in the podocytes of patients with FSGS and found that all members are downregulated. Treating cultured human podocytes with TGF-ß, LPS, or puromycin aminonucleoside (PAN) also downregulated the miR-30 family. Podocyte cytoskeletal damage and apoptosis caused by treatment with TGF-ß or PAN were ameliorated by exogenous miR-30 expression and aggravated by miR-30 knockdown. Moreover, we found that miR-30s exert their protective roles by direct inhibition of Notch1 and p53, which mediate podocyte injury. In rats, treatment with PAN substantially downregulated podocyte miR-30s and induced proteinuria and podocyte injury; however, transfer of exogenous miR-30a to podocytes of PAN-treated rats ameliorated proteinuria and podocyte injury and reduced Notch1 activation. Finally, we demonstrated that glucocorticoid treatment maintains miR-30 expression in cultured podocytes treated with TGF-ß, LPS, or PAN and in the podocytes of PAN-treated rats. Glucocorticoid-sustained miR-30 expression associated with reduced Notch1 activation and alleviated podocyte damage. Taken together, these findings demonstrate that miR-30s protect podocytes by targeting Notch1 and p53 and that the loss of miR-30s facilitates podocyte injury. In addition, sustained miR-30 expression may be a novel mechanism underlying the therapeutic effectiveness of glucocorticoids in treating podocytopathy.

Influence of eight unclassified missense variants of the MLH1 gene on Lynch syndrome susceptibility.

Missense mutations in MLH1 have frequently been detected in patients with Lynch syndrome, but their genetic significance has not been extensively assessed. In this study, we attempt to evaluate the etiological role of eight MLH1 missense variants. The variants were analyzed for their ability to affect MLH1 protein interaction with its partner PMS2 in vivo employing a yeast two-hybrid system. In addition, a SIFT (sorting intolerant from tolerant) algorithm was adopted to predict the effects of amino acid substitutions. Finally, scanning of mutations in a normal Chinese population and assay of the clinical characteristics have all been taken into account. Our results demonstrated that the MLH1 variants D485E and L653R cause functional alterations of the human MutLα complex significantly. The R265C, D304V, A586P, and R755S variants affect partial interaction. The remaining two variants, N38D and L559R, could be nonfunctional polymorphisms or might affect the mismatch repair system through other mechanisms.