Protective activities of ellagic acid and urolithins against kidney toxicity of environmental pollutants: A review

Oxidative stress and inflammation are two possible mechanisms related to nephrotoxicity caused by environmental pollutants. Ellagic acid, a powerful antioxidant phytochemical, may have great relevance in mitigating pollutant-induced nephrotoxicity and preventing the progression of kidney disease. This review discusses the latest findings on the protective effects of ellagic acid, its metabolic derivatives, the urolithins, against kidney toxicity caused by heavy metals, pesticides, mycotoxins, and organic air pollutants. We describe the chelating, antioxidant, anti-inflammatory, antifibrotic, antiautophagic, and antiapoptotic properties of ellagic acid to attenuate nephrotoxicity. Furthermore, we present the molecular targets and signaling pathways that are regulated by these antioxidants, and suggest some others that should be explored. Nevertheless, the number of reports is still limited to establish the efficacy of ellagic acid against kidney damage induced by environmental pollutants. Therefore, additional preclinical studies on this topic are required, as well as the development of well-designed clinical trials.     

深圳市龙岗区大气污染物与医院呼吸系统疾病门诊量的广义相加模型分析

目的 探讨深圳市龙岗区主要大气污染物(SO₂、NO₂、PM₁₀与PM_2.5)与医院呼吸系统疾病门诊量的关系。 方法 收集2013年1月1日－2015年12月31日深圳市龙岗区2家公立医院呼吸系统疾病逐日门诊量资料,深圳市龙岗区逐日大气污染物浓度及逐日气象资料分别来自深圳市环境监测站及气象局,运用时间序列分析广义相加模型对大气污染物日均浓度与呼吸系统疾病门诊量的关系及滞后效应进行分析。 结果 深圳市龙岗区2013－2015年SO₂ 、NO₂ 、PM₁₀ 与PM_2.5浓度中位数分别为8.08、38.08、46.05 μg/m³及31.04 μg/m³。2家医院三年呼吸系统门诊总量为549 169人次,日门诊量中位数为499人次/d。广义相加模型分析结果表明,除NO₂对呼吸系统疾病门诊量影响差异无统计学意义外,其余三种污染物对呼吸系统疾病门诊量影响均存在滞后效应,污染物每升高10 μg/m³,滞后2 d时SO₂对门诊量影响最强(相对危险度RR为1.030 7,95%CI:1.015 7~1.045 9),滞后3 d时PM₁₀与PM_2.5浓度对呼吸系统疾病门诊量影响最强(PM₁₀:RR=1.005 4,95%CI:1.002 8~1.008 0,PM_2.5:RR=1.006 0, 95%CI:1.002 7~1.009 4)。 结论 深圳市龙岗区大气SO₂、PM₁₀与PM_2.5浓度对医院呼吸系统疾病门诊量影响存在滞后效应。     

The Relationship Between Air Pollution and Lung Cancer in Nonsmokers in Taiwan

Introduction

For never-smokers (smoked <100 lifetime cigarettes), lung cancer (LC) has emerged as an important issue. We aimed to investigate the effects of prevalence changes in tobacco smoking and particulate matter (PM) 2.5 (PM_2.5) levels on LC in Taiwan, in relation to contrasting PM_2.5 levels, between Northern Taiwan (NT) and Southern Taiwan (ST).

Peat smoke inhalation alters blood pressure,baroreflex sensitivity,and cardiac arrhythmia risk in rats

ABSTRACT

Wildland fires (WF) are linked to adverse health impacts related to poor air quality. The cardiovascular impacts of emissions from specific biomass sources are however unknown. The purpose of this study was to assess the cardiovascular impacts of a single exposure to peat smoke, a key regional WF air pollution source, and relate these to baroreceptor sensitivity and inflammation. Three-month-old male Wistar-Kyoto rats, implanted with radiotelemeters for continuous monitoring of heart rate (HR), blood pressure (BP), and spontaneous baroreflex sensitivity (BRS), were exposed once, for 1-hr, to filtered air or low (0.38 mg/m³ PM) or high (4.04 mg/m³) concentrations of peat smoke. Systemic markers of inflammation and sensitivity to aconitine-induced cardiac arrhythmias, a measure of latent myocardial vulnerability, were assessed in separate cohorts of rats 24 hr after exposure. PM size (low peat = 0.4–0.5 microns vs. high peat = 0.8–1.2 microns) and proportion of organic carbon (low peat = 77% vs. high peat = 65%) varied with exposure level. Exposure to high peat and to a lesser extent low peat increased systolic and diastolic BP relative to filtered air. In contrast, only exposure to low peat elevated BRS and aconitine-induced arrhythmogenesis relative to filtered air and increased circulating levels of low-density lipoprotein cholesterol, complement components C3 and C4, angiotensin-converting enzyme (ACE), and white blood cells. Taken together, exposure to peat smoke produced overt and latent cardiovascular consequences that were likely influenced by physicochemical characteristics of the smoke and associated adaptive homeostatic mechanisms.     

Low-dose-rate iodine-125 seed air kerma strength measurement intercomparison

PurposeThe purpose of this study was to investigate the rate of compliance of air kerma strength (AKS) measurements of iodine-125 (I-125) seeds with international recommendations by departments in Australia and determine the potential impact of noncompliance.Methods and MaterialsTo achieve this aim, we present an intercomparison of AKS measurements for a single I-125 seed performed by 11 radiotherapy departments in Australia. Measurements were performed at two sites, with each participating department traveling to one of the two host sites and measuring the AKS using their own equipment and local protocols. Each of the AKS measurements was compared with each other and the manufacturer-certified AKS.ResultsNine of the 11 participating departments measured AKS fell within ±3% of the manufacturer's calibration certificate value, whereas all participating departments measured AKS within ±5% of the manufacturer's calibration certificate value. The total spread of the measured AKS among the 11 departments was 7.7%. Only two of the 11 participating departments complied with international recommendations and had their well chamber calibrated within the last 2 years. In addition, 2 of the 11 departments used a well chamber calibrated that was calibrated with a different seed model used during the intercomparison, whereas 4 of the 11 departments calibrated their well chamber “in-house” using a factory-calibrated seed provided by the seed manufacturer.ConclusionsA significant variation in the methods used and frequency of calibration of well chambers were observed among the participating departments. The results of this study support the international recommendations on frequency and methodology of well chamber calibration. Failure to follow these recommendations significantly increases the uncertainty in AKS measurement of I-125 seeds.     

Influenza vaccination and the endurance against air pollution among elderly with acute coronary syndrome

ObjectiveAir pollution, weather condition and influenza are known risk factors of acute coronary syndrome (ACS) among elderly people. The influenza vaccine (IV) has been shown to reduce major cardiovascular events. The purpose of this study was to compare resistance to air pollution and weather factors causing ACS between vaccinated and less-vaccinated elderly people.MethodsA case–crossover design was applied to 1835 elderly ACS patients who were obtained from the 1-million sample of Taiwan National Health Insurance Research Data with inclusion criteria: (1) the first diagnosis of ACS was in cold season and at age 68 or more, (2) had received the free IV program at least once during the period 3 years before the ACS. They were stratified into two groups: 707 had received flu vaccinations for all the 3 years and the remaining 1128 had not. The measurements of air pollutants, temperature, and humidity corresponding to each of the 3 days prior to the ACS diagnosis date were retrieved from the data banks of the Taiwan Environmental Protection Administration and Central Weather Bureau.FindingsIncreases in air pollution concentrations of CO, NO₂, PM₁₀ or PM_2.5 and decreases in temperature significantly influenced the risk of ACS for the non-continuously vaccinated elderly population; however, less significant effects were observed for the continuously vaccinated population.ConclusionConsecutive influenza vaccination may potentially offer resistance against the detrimental effects of air pollution and changes in temperature in frail elderly adults with ACS. Future studies are needed to directly assess the interaction effect between the vaccination and environmental factors on ACS.     

Coronary Artery Embolism: Two Case Reports and a Review of the Literature

Coronary embolism (CE) is an uncommon and unique cause of acute myocardial infarction. In this report, we review 216 cases of CE including 2 new cases from our institution. The mean patient age was 52.5 years and 62% of the patients were males. Chest pain was the most common presenting symptom followed by dyspnea, and the most commonly affected vessel was the left anterior descending artery. Leading etiologies of the embolus were atrial fibrillation, septic emboli, and iatrogenic causes. Treatment approaches varied with thrombus aspiration being used in 30% of cases. In-hospital mortality rate was 36% and 13% of the cases were complicated by cerebrovascular accident. CE is a unique pathology that leads to acute myocardial infarction. It portends a high mortality rate and requires a high level of suspicion as symptoms may be misleading. Further research is needed in order to improve recognition and management and to lower associated mortality.     

Niacinamide and 12‐hydroxystearic acid prevented benzo(a)pyrene and squalene peroxides induced hyperpigmentation in skin equivalent

Skin surface is constantly exposed to environmental and secreted stressors such as UV, air pollution and peroxidized sebum. The current study aims to use reconstructed human skin equivalents to demonstrate topical stressor‐induced hyperpigmentation and evaluate bioactives’ potential protective effect. Given that polycyclic aromatic hydrocarbons are representative airborne particle‐bound organic compounds with known relevance to pigmentation pathways, benzo(a)pyrene was selected as surrogate environmental toxin. On the other hand, squalene monohydroperoxides are well‐characterized sebum peroxidation product under UV and pollutant exposure, thus are used as another representative skin stressor. With 3‐day continuous exposure, 30 pmol/cm² of benzo(a)pyrene and 3.4 nmol/cm² of squalene monohydroperoxides induced significant viability loss, inflammatory response, and approximately 10 shades of pigmentation increase in pigmented living skin equivalents. At the same time, pretreatment and co‐treatment with 12‐hydroxystearic acid (12‐HSA, 20 μmol/L) or niacinamide (5 mmol/L) ameliorated such stressor‐induced consequences. Niacinamide was particularly effective against benzo(a)pyrene damage, probably as a substrate for important NAD+ dependent detoxification pathways, while 12‐HSA was potent against squalene monohydroperoxides through barrier enhancing, anti‐inflammatory, and anti‐oxidative mechanisms. In summary, topical stressor‐induced hyperpigmentation was achieved in vitro, with known bioactives showing protective benefits.