Gene polymorphisms of interleukin-10 and tumor necrosis factor-α are associated with contrast-induced nephropathy

Coping Behaviors and Incident Kidney Disease

Key Points

Adaptive coping behaviors are associated with lower odds of incident CKD. Coping behaviors could represent a target to prevent CKD.

Background

How someone copes may alter the trajectory of their kidney function. We aimed to evaluate whether coping behaviors were associated with incident CKD or rapid kidney function decline.

Methods

We used data from the Healthy Aging in Neighborhoods of Diversity across the Life Span study (Baltimore, MD) for this longitudinal analysis. Adaptive and maladaptive coping behavioral constructs were measured using the Brief COPE Inventory at visit 1. We used multiple logistic regression to assess the odds of incident CKD and rapid kidney function decline per point increase in coping scales and adjusted for baseline demographics and clinical variables.

Results

Of 1935 participants, mean age was 48 years, 44% were male, 56% were Black persons, and baseline mean (SD) eGFR was 91 (16) ml/min per 1.73 m2. After a median of 8.2 years, 113 participants developed incident CKD and 341 had rapid kidney function decline. Compared with those who reported they usually did not use adaptive coping behaviors at all (such as emotional support), those with the highest use of adaptive coping had lower odds of incident CKD. Every 1-unit increase in adaptive coping corresponded with a 2% lower adjusted odds of incident CKD (odds ratio, 0.98; 95% confidence interval, 0.95 to 0.99). There was no association between maladaptive coping behaviors and incident CKD. Coping behaviors were not associated with rapid kidney function decline.

Conclusions

Adaptive coping behaviors were associated with lower odds of incident CKD and could represent a target to facilitate CKD prevention. The role of medical care in this association is an area worthy of further investigation.

Interaction between Single Nucleotide Polymorphisms (SNP) of Tumor Necrosis Factor-Alpha (TNF-α) Gene and Plasma Arsenic and the Effect on Estimated Glomerular Filtration Rate (eGFR)

When poisons enter the human body, tumor necrosis factor (TNF-α) will increase and cause damage to tissues through oxidative stress or inflammatory reaction. In previous studies, arsenic (As) has known to cause many health problems. Some studies have shown that As exposure is negatively correlated with estimated glomerular filtration rate (eGFR), or with the prevalence of proteinuria. At present, there are few studies focusing on the effects of As exposure and TNF-α single nucleotide polymorphism (SNP) to eGFR; thus, this study was intended to explore the interactions between TNF-α SNPs and plasma As and their effects on eGFR. A cohort of 500 adults, aged 30 to 70 years, was randomly selected from Taiwan Biobank (TWB). We used the gene chip to screen out seven SNPs of the TNF-α gene and used the results, combined with questionnaires, biochemical tests, and stored plasma samples from the TWB, for the analysis of As by inductively coupled plasma mass spectrometry (ICP-MS). After adjustments for BMI, hypertension, hyperlipidemia, kidney stones, and smoking habits, multiple regression statistics were performed to explore the interaction between SNPs and plasma As with eGFR. In this sample of the general population, plasma As had a significant association with the decline of eGFR (β (SE) = −7.92 (1.70), p < 0.0001). TNF-α gene SNP rs1800629 had the property of regulating TNF-α, which interacts with plasma As; individuals with the AG type had a significantly lower eGFR than those with the GG type, by 9.59 mL/min/1.73 m2 (p < 0.05), which, regarding the dominant model, could infer that the A allele is a risk allele. SNP rs769177 had no interaction with plasma As; however, participants with the TT or TC type had significantly higher eGFR levels than the CC carriers, by 4.02 mL/min/1.73 m2 (p < 0.05). While rs769176 interacted with plasma As, if a person with the TC type had a higher plasma As concentration, that would sustain higher eGFR. This study found that certain SNPs of the TNF-α gene would be robust to the decline of eGFR caused by As exposure. Still, we need further research to confirm the protective regulation mechanism of these SNPs.

Genetic Susceptibility to Acute Kidney Injury

Acute kidney injury (AKI) is a widely held concern related to a substantial burden of morbidity, mortality and expenditure in the healthcare system. AKI is not a simple illness but a complex conglomeration of syndromes that often occurs as part of other syndromes in its wide clinical spectrum of the disease. Genetic factors have been suggested as potentially responsible for its susceptibility and severity. As there is no current cure nor an effective treatment other than generally accepted supportive measures and renal replacement therapy, updated knowledge of the genetic implications may serve as a strategic tactic to counteract its dire consequences. Further understanding of the genetics that predispose AKI may shed light on novel approaches for the prevention and treatment of this condition. This review attempts to address the role of key genes in the appearance and development of AKI, providing not only a comprehensive update of the intertwined process involved but also identifying specific markers that could serve as precise targets for further AKI therapies.

Predictive Ability of Procalcitonin for Acute Kidney Injury: A Narrative Review Focusing on the Interference of Infection

Acute kidney injury (AKI) is a common yet complicated clinical entity with high morbidity and mortality. An essential strategy to improve AKI patients’ prognoses is finding optimal biomarkers to identify AKI in a timely manner. Procalcitonin (PCT), a well-recognized biomarker for diagnosing infection and guiding antibiotics therapy, has been proposed to predict AKI development and recovery in many clinical settings. The current review provides comprehensive and updated information from relevant studies to evaluate PCT’s AKI-predictive ability and the influence of infection on this predictive ability. PCT has demonstrated optimal predictive ability for AKI in various populations irrespective of infection. However, the predictive ability seems to be blunted by infection since infection and inflammation have a more potent influence than AKI on PCT elevation. We furthermore explain the complicated association between elevated PCT levels and AKI in infection and inflammation situations and recommend directions for further investigations to clarify the essential issue. In conclusion, although conflicting data exist, serum PCT level is a potential biomarker for predicting AKI in many clinical settings regardless of infection. Nevertheless, further studies are warranted to clarify the association between PCT, infection, and AKI and to confirm the utilization of PCT for AKI prediction.

IL-10 -1082 A/G polymorphism is related with the risk and clinical characteristics of acute kidney injury: a case-control study

Background

Interleukin-10 (IL-10), a kind of anti-inflammation cytokine, has a key role in the development of acute kidney injury (AKI). Recently, several studies addressed the link between the risk of AKI and the IL-10 -1082 A/G polymorphism with conflicting findings.

Methods

To identify the effects of the IL-10 -1082 A/G polymorphism on the risk of AKI, we designed this case-control study. This study recruited 320 AKI patients and 408 ICU patients without AKI. The association between the AKI risk and this polymorphism was analyzed using the logistic regression analysis adjusted for confounding factors.

Results

The IL-10 -1082 A/G polymorphism enhanced the risk of AKI. After stratified analysis, this polymorphism increased the risk of AKI among the males, smokers, those aged exceeding 60 years old, and overweight individuals (BMI ≥ 25). Moreover, -1082 A/G polymorphism was remarkably related with APACHE II score and eGFR.

Conclusions

Collectively, the IL-10 -1082 A/G polymorphism is linked with an elevated risk of AKI. Further studies in China need be performed to verify these results.

Meta-analysis of procalcitonin as a predictor for acute kidney injury

BACKGROUND

Procalcitonin (PCT) was used for predicting the development of acute kidney injury (AKI) in several studies recently. We aimed to investigate the accuracy of PCT for predicting AKI in this study.

METHODS

Studies that assessed the predictive performance of PCT for the development of AKI in adult patients were searched from Medline, Embase, and the Cochrane Library from inception to June 2020. We calculated the pooled sensitivities and specificities and the area under the summary receiver-operating characteristic (SROC) curves. I2 was used to test the heterogeneity and the potential heterogeneity was investigated by meta-regression.

RESULTS

In total, 9 of 119 studies with 4852 patients were included, 1272 were diagnosed with AKI. In the overall analysis, the area under the SROC curve was 0.82 (95% CI, 0.79-0.85) and the pooled sensitivity and specificity were 0.76 (95% confidence interval [CI], 0.64-0.85) and 0.75 (95% CI, 0.61-0.86), respectively. In the subgroup analysis among septic patients, the pooled sensitivity and specificity were 0.59 (95% CI, 0.29-0.84) and 0.53 (95% CI, 0.31-0.74), and the area under the SROC was 0.57 (95% CI, 0.53-0.62).

CONCLUSION

PCT may be a potential predictor for the development of AKI.

Ethnicity-Stratified Analysis of the Association between TNF-α Genetic Polymorphisms and Acute Kidney Injury: A Systematic Review and Meta-Analysis

Background

Several studies have reported conflicting findings regarding the association between tumor necrosis factor-alpha (TNF-α) genetic polymorphisms and acute kidney injury (AKI). Therefore, we performed this meta-analysis to further investigate whether TNF-α variants are related to AKI susceptibility.

Methods

A comprehensive search of observational studies on the association of TNF-α polymorphism with AKI susceptibility was conducted in the PubMed, Cochrane, and Embase databases through February 10, 2020. Pooled odds ratios (ORs) and 95% corresponding confidence intervals (95% CIs) were analyzed to evaluate the strength of the relationship.

Results

A total of 8 studies involving 6694 patients (2559 cases and 4135 controls) were included. Pooled analysis showed a trend of increased risk between the TNF-α rs1800629 variant and AKI (A vs. G: OR [95%CI] = 1.33 [0.98‐1.81]) among the overall population. Ethnicity-stratified analysis indicated that the TNF-α rs1800629 variant was a risk factor for Asians (OR [95%CI] = 1.93 [1.59‐2.35]) while it is not for Caucasians (OR [95%CI] = 1.04 [0.91‐1.20]). Additionally, we also found that TNF-α rs1799964 polymorphism was observed to have a significant relationship with AKI risk in Asian patients (C vs. T, OR [95%CI] = 1.26 [1.11‐1.43]).

Conclusions

The TNF rs1800629 polymorphism exhibited a trend toward AKI susceptibility with ethnic differences. The relationship was found to be significant among the Asian population, but not among those of Caucasian origin. Additionally, the TNF-α rs1799964 polymorphism was also related to a significantly increased risk of AKI in Asians.

Meta-analysis of effect of renin-angiotensin-aldosterone system blockers on contrast-induced nephropathy

Background:

The purpose of this study was to systematically evaluate the effect of renin–angiotensin–aldosterone system blockers on the incidence of contrast-induced nephropathy in patients undergoing coronary angiography or percutaneous coronary intervention.

Methods:

A systematic literature search of several databases was conducted to identify studies that met the inclusion criteria. A total of 12 studies with 14 trials that performed studies on a total of 4864 patients (2484 treated with renin–angiotensin–aldosterone system blockers and 2380 in the control group) were included. The primary endpoint was the overall incidence of contrast-induced nephropathy. Analyses were performed with STATA version 12.0.

Results:

The overall contrast-induced nephropathy incidence in renin–angiotensin–aldosterone system blocker and control groups was 10.43% and 6.81%, respectively. The pooled relative risk of contrast-induced nephropathy incidence was 1.22 (95% confidence interval: 0.81–1.84) in the renin–angiotensin–aldosterone system blocker group. An increased risk of developing contrast-induced nephropathy in the renin–angiotensin–aldosterone system blocker group was observed among older people, non-Asians, chronic users, and studies with larger sample size, and the pooled RRs and 95% confidence intervals were 2.02 (1.21–3.36), 2.30 (1.41–3.76), 1.69 (1.10–2.59) and 1.83 (1.28–2.63), respectively.

Conclusions:

Intervention with renin–angiotensin–aldosterone system blockers was associated with an increased risk of contrast-induced nephropathy among non-Asians, chronic users, older people, and studies with larger sample size. Large clinical trials with strict inclusion criteria are needed to confirm our results and to evaluate the effect further.

Biomarkers for Diagnosis and Prediction of Outcomes in Contrast-Induced Nephropathy

Background

Serum creatinine is suboptimal as a biomarker in the early diagnosis of contrast-induced nephropathy (CIN). In this study, we investigated a panel of novel biomarkers in the early diagnosis of CIN and in assessing patient outcomes.

Methods

This single-centre, nested, prospective case-controlled study included 30 patients with CIN and 60 matched controls. Serum and urine samples were collected before contrast administration and at 24 hours, 48 hours, and ≥5 days after contrast administration. Concentrations of NGAL, cystatin C, β₂M, IL18, IL10, KIM1, and TNFα were determined using Luminex and ELISA assays. Outcomes were biomarker diagnostic discrimination performance for CIN and mortality after generation of area under receiver operating characteristic curves (AUROCs).

Results

Median serum levels for 24 h cystatin C (p < 0.01) and 48 h β₂M levels (p < 0.001) and baseline urine NGAL (p=0.02) were higher in CIN patients compared to controls with AUROCs of 0.75, 0.78, and 0.74, respectively, for the early diagnosis of CIN. Serum β₂M levels were higher in CIN patients at all time points. Elevated baseline serum concentrations of IL18 (p < 0.001), β₂M (p=0.04), TNFα (p < 0.001), and baseline urine KIM (p=0.01) and 24 h urine NGAL (p=0.02) were significantly associated with mortality. Baseline serum concentrations of IL18, β₂M, and TNFα showed the best discrimination performance for mortality with AUROCs, all >0.80. Baseline NGAL was superior for excluding patients at risk for CIN, with positive and negative predictive ranges of 0.50–0.55 and 0.81–0.88, respectively. Cystatin C (p=0.003) and β₂M (p=0.03) at 24 h independently predicted CIN risk. β₂M predicted increased mortality of 40% at baseline and 50% at 24 hours.

Conclusion

Serum cystatin C at 24 h was the best biomarker for CIN diagnosis, while baseline levels of serum IL18, β₂M, and TNFα were best for predicting prognosis.

Elevated high-sensitivity C-reactive protein combined with procalcitonin predicts high risk of contrast-induced nephropathy after percutaneous coronary intervention

Background

Contrast-induced nephropathy (CIN) is common after percutaneous coronary intervention (PCI) and always leads to a poor prognosis. Compared with conventional detection methods, either high-sensitivity C-reactive protein (hs-CRP) or procalcitonin have higher sensitivity and specificity for predicting CIN, but their combination has not been explored. This prospective study investigated the value of hs-CRP combined with procalcitonin for predicting CIN after PCI.

Methods

All patients undergoing PCI admitted to our hospital during the year 2016 were consecutively enrolled (n = 343). The patients received adequate hydration before PCI and 20 mg furosemide after the procedure. CIN was diagnosed by a 25% elevation in serum creatinine or ≥ 44.2 μmol/L (0.5 mg/dL) serum creatinine within 48 to 72 h after intravenous injection of contrast media.

Results

Patients with high hs-CRP or procalcitonin had higher rates of CIN relative to those patients with low values. For predicting CIN, hs-CRP combined with procalcitonin showed an area under the receiver operating characteristic curve of 0.67, with optimal cut-off value 0.0643610, and the sensitivity and specificity were higher than hs-CRP or procalcitonin alone. The logistic regression analysis showed that high-risk factors of CIN were acute myocardial infarction and highly elevated hsCRP and procalcitonin.

Conclusions

Prior to PCI, an elevation of the inflammatory biomarkers hsCRP and procalcitonin are a risk factor for postoperative CIN. This study suggests that the combination of hsCRP and procalcitonin is a better predictor of CIN after PCI then either hsCRP or procalcitonin alone.

Trial registration number

ChiCTR-IOR-14005250. Date of registration 2014-09-24.

Association between acute kidney injury and serum procalcitonin levels and their diagnostic usefulness in critically ill patients

Procalcitonin (PCT) is a useful marker for the diagnosis of systemic inflammatory response syndrome. In addition, PCT is affected by renal function. However, few studies have investigated the relationship between PCT and the development of acute kidney injury (AKI). Hence, we investigated whether serum PCT levels at the time of admission were associated with the development of AKI and clinical outcomes. A total of 790 patients in whom PCT was measured on admission to the intensive care unit (ICU) were analyzed retrospectively. We attempted to investigate whether serum PCT levels measured at the time of admission could be used as a risk factor for the development of AKI in septic and nonseptic patients or as a risk factor for all-cause mortality, and diagnostic usefulness of PCT was further assessed. Serum PCT levels were significantly higher in patients with AKI than in those without AKI (P < 0.001). After multivariable adjustment for clinical factors, laboratory findings, and comorbidities, PCT as a continuous variable showed a significant association with AKI (OR 1.006, 95% CI [1.000–1.011]; P = 0.035). However, PCT was not effective in predicting mortality. The cut-off value of PCT for the prediction of AKI incidence was calculated to be 0.315 ng/ml, with sensitivity and specificity of 60.9% and 56.9%, respectively. The odds ratios (ORs) from an equation adjusted for optimum thresholds of PCT levels for developing AKI with and without sepsis were 2.422 (1.222–4.802, P = 0.011) and 1.798 (1.101–2.937, P = 0.019), respectively. However, there were no absolute differences between the pre- and posttest probabilities after including the PCT value for AKI development. This study suggests that the PCT value was higher in AKI patients than in non-AKI patients, but PCT measurement at the time of admission did not improve the prediction model for AKI.

Common Inflammation-Related Candidate Gene Variants and Acute Kidney Injury in 2647 Critically Ill Finnish Patients

Acute kidney injury (AKI) is a syndrome with high incidence among the critically ill. Because the clinical variables and currently used biomarkers have failed to predict the individual susceptibility to AKI, candidate gene variants for the trait have been studied. Studies about genetic predisposition to AKI have been mainly underpowered and of moderate quality. We report the association study of 27 genetic variants in a cohort of Finnish critically ill patients, focusing on the replication of associations detected with variants in genes related to inflammation, cell survival, or circulation. In this prospective, observational Finnish Acute Kidney Injury (FINNAKI) study, 2647 patients without chronic kidney disease were genotyped. We defined AKI according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria. We compared severe AKI (Stages 2 and 3, n = 625) to controls (Stage 0, n = 1582). For genotyping we used iPLEX^TM Assay (Agena Bioscience). We performed the association analyses with PLINK software, using an additive genetic model in logistic regression. Despite the numerous, although contradictory, studies about association between polymorphisms rs1800629 in TNFA and rs1800896 in IL10 and AKI, we found no association (odds ratios 1.06 (95% CI 0.89–1.28, p = 0.51) and 0.92 (95% CI 0.80–1.05, p = 0.20), respectively). Adjusting for confounders did not change the results. To conclude, we could not confirm the associations reported in previous studies in a cohort of critically ill patients.

Genetic variants and acute kidney injury: A review of the literature

PURPOSE

Limited data exists on potential genetic contributors to acute kidney injury. This review examines current knowledge of AKI genomics.

MATERIALS AND METHODS

32 studies were selected from PubMed and GWAS Catalog queries for original data studies of human AKI genetics. Hand search of references identified 3 additional manuscripts.

RESULTS

33 of 35 studies were hypothesis-driven investigations of candidate polymorphisms that either did not consistently replicate statistically significant findings, or obtained significant results only in few small-scale studies. Vote-counting meta-analysis of 9 variants examined in >1 candidate gene study showed ≥50% non-significant studies, with larger studies generally finding non-significant results. The remaining 2 studies were large-scale unbiased investigations: One examining 2,100 genes linked with cardiovascular, metabolic, and inflammatory syndromes identified BCL2, SERPINA4, and SIK3 variants, while a genome-wide association study (GWAS) identified variants in BBS9 and the GRM7|LMCD1-AS1 intergenic region. All studies had relatively small sample sizes (<2300 subjects). Study heterogeneity precluded candidate gene and GWA meta-analysis.

CONCLUSIONS

Most studies of AKI genetics involve hypothesis-driven (rather than hypothesis-generating) candidate gene investigations that have failed to identify contributory variants consistently. A limited number of unbiased, larger-scale studies have been carried out, but there remains a pressing need for additional GWA studies.

Atorvastatin protects against contrast-induced nephropathy via anti-apoptosis by the upregulation of Hsp27 in vivo and in vitro

Contrast-induced nephropathy (CIN) is an iatrogenic acute renal failure occurring following the intravascular injection of iodinated radiographic contrast medium. However, the regulatory mechanisms for CIN remain to be fully elucidated. The present study aimed to investigate whether atorvastatin protects against CIN via anti-apoptotic effects by the upregulation of Hsp27 in vivo and in vitro. To determine whether atorvastatin attenuated CIN, the inflammatory response and apoptosis in vivo and in vitro, a rat model of iopamidol-induced CIN was used, and human embryonic proximal tubule (HK2) cell damage was assessed. The rats were assigned into four groups (n=10 per group), as follows: Control rats; rats+atorvastatin; rats + iopamidol; rats+iopamidol+atorvastatin. In vitro, the HK2 cells were treated with iopamidol in the presence or absence of atorvastatin, heat shock protein (Hsp)27 small interfering (si)RNA or pcDNA3.1-Hsp27. The renal tissues were examined histopathologically and collected for western blot analysis. The results showed that atorvastatin ameliorated the apoptosis and deterioration of renal function (P<0.05). Furthermore, atorvastatin reduced the iopamidol-induced activity of B cell lymphoma-2 (Bcl-2)-associated X protein (Bax)/caspase-3 and increased the expression of Bcl-2 in vivo and in vitro. Notably, following treatment with Hsp27 siRNA or pcDNA3.1-Hsp27, it was found that iopamidol enhanced or weakened the upregulation of Bax/caspase-3 and downregulation of Bcl-2 in the HK2 cells, respectively. The results of the present study suggested that atorvastatin protected against contrast-induced renal tubular cell apoptosis through the upregulation of Hsp27 in vivo and in vitro.

Xuezhikang ameliorates contrast media-induced nephropathy in rats via suppression of oxidative stress, inflammatory responses and apoptosis

BACKGROUND

The aim of this study was to assess the preventive effect of xuezhikang (XZK) to replace atorvastatin on the contrast media-induced acute kidney injury (CI-AKI).

METHODS

The male Sprague-Dawley rats were divided into five groups: group 1 (sham), injected with normal saline; group 2 (XZK), treated with XZK; group 3 contrast media (CM), injected with CM; group 4 (CM + ATO), injected with CM + pretreatment with atorvastatin; group 5 (CM + XZK), injected with CM + pretreatment with XZK. Twenty-four hours after injection with normal saline or CM, the blood sample and the kidneys were collected for the measurement of biochemical parameters, oxidative stress markers, nitric oxide production, inflammatory parameters, as well as renal histopathology and apoptosis detection.

RESULTS

Our results indicated that XZK restored the renal function by reducing serum blood urea nitrogen (BUN) and serum creatinine (Scr), depressing renal malondialdehyde (MDA), increasing renal NO production, decreasing TNF-ɑ and IL-6 expression, attenuating renal pathological changes and inhibiting the apoptosis of renal tubular cells.

CONCLUSION

XZK's therapeutic effect is similar, or even better than atorvastatin at the same effectual dose in some parts.

Role of cytokine gene polymorphisms in acute and chronic kidney disease following liver transplantation

PURPOSE

Development of renal dysfunction, including acute kidney injury (AKI) and chronic kidney disease (CKD), after liver transplantation (LT) remains a critical issue adversely affecting patient survival in both the short and long term. Previous reports have suggested that inflammatory and antiinflammatory cytokines and their functionally relevant gene polymorphisms may play critical roles in the development of AKI and CKD. However, the involvement of these cytokines and their gene polymorphisms in renal deterioration following LT remains unclear.

METHODS

We examined 62 recipients who underwent LT at Nagoya University between 2004 and 2009 and who had survived for at least 1 year. The following gene polymorphisms in recipients were analyzed: tumor necrosis factor-A (TNFA) T-1031C, interleukin-2 (IL2) T-330G, IL10 C-819T, IL13 C-1111T, transforming growth factor-B (TGFB) T29C, and IL4 T-33C.

RESULTS

Thirteen patients (21 %) developed AKI within 4 weeks after LT. Of the investigated gene polymorphisms, the IL4 -33 T/T genotype was significantly associated with higher incidence of AKI compared with the other two genotypes [hazard ratio (HR) = 5.48, 95 % confidence interval (CI) 1.18-25.52, p = 0.03]. On the other hand, 16 patients (26 %) had developed CKD at median follow-up of 9.2 years after LT. We showed the lack of association between investigated gene polymorphisms in recipients and CKD development.

CONCLUSIONS

The IL4 -33 T/T genotype might be a risk factor for AKI in LT, and this might contribute to earlier withdrawal of immunosuppressive agents to minimize renal toxicity. In contrast, none of the investigated cytokine gene polymorphisms were associated with CKD.

Heat shock protein 70-2 and tumor necrosis factor-α gene polymorphisms in Chinese children with Henoch-Schönlein purpura

BACKGROUND

Henoch-Schönlein purpura (HSP) or IgA-associated vasculitis is related to immune disturbances. Polymorphisms of the heat shock protein 70-2 gene (HSP70-2) and the tumor necrosis factor-a gene (TNF-α) are known to be associated with immune diseases. The purpose of this study was to investigate the likely association of HSP70-2 (+1267A/G) and TNF-α (+308A/G) gene polymorphisms with HSP in children.

METHODS

The polymerase chain reaction restriction fragment length polymorphism method was used to detect the HSP70-2 and TNF-α polymorphisms in 205 cases of children with HSP and 53 controls; and the association of these polymorphisms with HSP and HSP nephritis (HSPN) was analyzed.

RESULTS

The G/G genotypic frequencies at the +1267A/G position of HSP70-2 in the HSP group (22.9%) were significantly higher than those in the healthy control group (9.4%) (χ(2)=4.764, P<0.05). The frequencies of the A/A, A/G and G/G genotypes of HSP70-2 in patients in the nephritis-free group and the HSPN group showed no statistically significant difference. The A/A genotype frequency at the +308G/A position of TNF-α in the HSP group was 8.3%, which was higher than that in the control group (χ(2)=6.447, P<0.05). The A allele frequency of TNF-α in the HSP group was higher than that in the control group, with a statistically significant difference (χ(2)=7.241, P<0.05).

CONCLUSIONS

The HSP70-2 (+1267A/G) and TNF-α (+308G/A) gene polymorphisms were associated with HSP in children. The G/G homozygosity of HSP70-2 and the A/A homozygosity of TNF-α may be genetic predisposing factors for HSP.

Genetic predisposition to acute kidney injury--a systematic review

BACKGROUND

The risk of an individual to develop an acute kidney injury (AKI), or its severity, cannot be reliably predicted by common clinical risk factors. Whether genetic risk factors have an explanatory role poses an interesting question, however. Thus, we conducted a systematic literature review regarding genetic predisposition to AKI or outcome of AKI patients.

METHODS

We searched Ovid SP (MEDLINE) and EMBASE databases and found 4027 references to AKI. Based on titles and abstracts, we approved 37 articles for further analysis. Nine were published only as abstracts, leaving 28 original articles in the final analysis. We extracted the first author, year of publication, study design, clinical setting, number of studied patients, patients with AKI, ethnicity of patients, studied polymorphisms, endpoints, AKI definition, phenotype, significant findings, and data for quality scoring from each article. We summarized the findings and scored the quality of articles.

RESULTS

The articles were quite heterogeneous and of moderate quality (mean 6.4 of 10).

CONCLUSIONS

Despite different gene polymorphisms with suggested associations with development or severity or outcome of AKI, definitive conclusions would require replication of associations in independent cohort studies and, preferably a hypothesis-free study design.

The A allele of cluster of differentiation 36 (CD36) SNP 1761667 associates with decreased lipid taste perception in obese Tunisian women

Recent studies have suggested that excessive intake of dietary fat is associated with obesity. Some obese subjects have been reported to exhibit high thresholds for the gustatory detection of lipids via lipid receptors, such as cluster of differentiation 36 (CD36). We studied lingual detection thresholds for emulsions containing oleic acid in obese Tunisian women (n 203) using a three-alternative forced choice (3-AFC) method. Genotyping of the TNF-α (rs1800629), IL-6 (rs1800795) and CD36 (rs1761667) genes was performed to associate with lipid taste perception thresholds. The CD36 genotype distribution was as follows: GG (n 42), AG (n 102) and AA (n 59). Women with the CD36 GG genotype exhibited oral detection thresholds for oleic acid that were more than three times lower than those with the CD36 AA genotype. The present study confirms a high threshold of gustatory fat detection in obese women with the CD36 AA genotype, but there is no significant association with the IL-6 and TNF-α gene polymorphisms.

Procalcitonin as an Early Predictor of Contrast-Induced Acute Kidney Injury in Patients With Acute Coronary Syndromes Who Underwent Percutaneous Coronary Intervention

Contrast-induced acute kidney injury (CI-AKI) is a major issue after percutaneous coronary intervention (PCI), especially in the setting of acute coronary syndrome (ACS). Contrast-induced acute kidney injury is associated with increased mortality and morbidity. Inflammation plays an important role in the pathophysiology of CI-AKI. Procalcitonin (PCT) is introduced as a new marker of inflammation. We sought to examine whether admission PCT levels predict the development of CI-AKI. Patients (n = 814) were divided into 2 groups, namely, CI-AKI (-) and CI-AKI (+). An increase in serum creatinine of ≥0.5 mg/dL from baseline within 48 to 72 hours of contrast exposure was defined as CI-AKI. Contrast-induced acute kidney injury occurred in 96 (11.8%) patients. The PCT levels were significantly higher in patients with CI-AKI than in those without, 0.11 (0.056-0.495) vs 0.04 (0.02-0.078) µg/L; P < .001. After multivariable analysis, PCT remained a significant independent predictor of CI-AKI (odds ratio 2.544; 95% CI [1.207-5.347]; P = .014) as well as age, women, white blood cell, hemoglobin, glomerular filtration rate, creatine kinase myocarial band, and SYNTAX score. In conclusion, serum PCT levels are independently associated with a risk of CI-AKI in patients with ACS who underwent urgent PCI.

Rosuvastatin attenuates contrast-induced nephropathy through modulation of nitric oxide, inflammatory responses, oxidative stress and apoptosis in diabetic male rats

Background

Contrast-induced nephropathy (CIN) is an important cause of acute renal failure. We observe the effect of rosuvastatin on preventing CIN in diabetic rats in current study.

Methods

Diabetic rats were then divided into five groups: 1 diabetic rats (D), 2 diabetic rats + contrast media (DCM), 3 diabetic rats + rosuvastatin (DR), 4 diabetic rats + contrast media + rosuvastatin (DRCM), 5 non-diabetic rat control (NDCM). Contrast-induced nephropathy was induced by intravenous injection a single dose of indomethacin (10 mg/kg), double doses of N-nitro-L-arginine methyl ester (10 mg/kg) and a single dose of high-osmolar contrast medium meglumine amidotrizoate (6 ml/kg). DR and DRCM group rats were treated with rosuvastatin (10 mg/kg/day) by gavage for 5 days. At the end of treatment, the experimental groups were sacrificed, and their renal tissues were investigated histopathologically beside assessments of functional activities, nitric oxide metabolites, and oxidative stress and apoptic markers.

Results

After 6 days, serum creatinine and urine microprotein were increased, and creatinine clearance, kidney nitrite were decreased in DCM rats compared with NDCM, D, DR and DRCM groups. Histopathology scores in group DCM were increased compared with groups NDCM, D and DR, but lower in group DRCM than in group DCM (p < 0.01). Kidney thiobarbituric acid-reacting substances (TBARS), serum malondialdehyde (MDA), and serum protein carbonyl content (PCC) were increased, and serum thiol was decreased in the DCM group compared with groups NDCM, D and DR; however, these results were reversed in group DRCM compared with group DCM. Both expression of IL-6, TNF-α and the percentage of apoptotic cells were increased in group DCM than in groups NDCM, D and DR, but they were decreased in group DRCM than in group DCM. The expression of phospho-p38, cleaved capase-3, and the Bax/Bcl-2 ratio, were increased in group DCM than in groups NDCM, D and DR, but were decreased in group DRCM than in group DCM.

Conclusions

Our study demonstrated that rosuvastatin treatment attenuated both inflammatory processes and apoptosis and inhibited oxidative stress and the p38 MAPK pathway in a diabetic rat model in the setting of CIN.