Iodine-131 and thyroid function

Effects of whole seaweed consumption on humans: current evidence from randomized-controlled intervention trials, knowledge gaps, and limitations

Seaweed is often recognized for its potential health benefits, attributed to its abundance of dietary fibers, protein, and polyphenols. While human observational studies have shown promise, the collective evidence from human intervention trials remains limited. This narrative review aims to comprehensively analyze the effects of seaweed intake on humans, while critically assessing the methodology, including Cochrane risk-of-bias assessment. A search was conducted in online databases, including PubMed, Scopus, and Google Scholar, covering the period from 2000 to May 2023. The focus was on randomized controlled clinical trials (RCTs) evaluating the impact of whole seaweed, either consumed as capsules, integrated into food products or as part of meals. Various health outcomes were examined, including appetite, anthropometric measures, cardiometabolic risk factors, thyroid function, markers of oxidative stress, and blood mineral concentrations. Out of the 25 RCTs reviewed, the findings revealed limited yet encouraging evidence for effects of seaweed on blood glucose metabolism, blood pressure, anthropometric measures, and, to a lesser extent, blood lipids. Notably, these favorable effects were predominantly observed in populations with type-2 diabetes and hypertension. Despite most trials selecting a seaweed dose aligning with estimated consumption levels in Japan, considerable variability was observed in the pretreatment and delivery methods of seaweed across studies. Moreover, most studies exhibited a moderate-to-high risk of bias, posing challenges in drawing definitive conclusions. Overall, this review highlights the necessity for well-designed RCTs with transparent reporting of methods and results. Furthermore, there is a need for RCTs to explore seaweed species cultivated outside of Asia, with a specific emphasis on green and red species. Such studies will provide robust evidence-based support for the growing utilization of seaweed as a dietary component in regions with negligible seaweed consumption, e.g., Europe.

Increased bisphenol A levels in Thai children and adolescents with type 1 diabetes mellitus

BACKGROUND

The incidence of type 1 diabetes mellitus (T1DM) in children and adolescents continues to increase worldwide. The reason for this is unclear. In addition to the role of genetics, bisphenol A (BPA) has been investigated as a possible causal factor for T1DM. This study aimed to determine the correlation between urinary BPA levels and T1DM in Thai children and adolescents.

METHODS

A cross-sectional study was conducted in T1DM patients who were followed at the endocrinology clinic at King Chulalongkorn Memorial Hospital from December 2018 to December 2019 and age-matched healthy controls. Urinary BPA levels were analyzed by high-performance liquid chromatography and adjusted by urine creatinine. Anthropometric data were measured in all participants and clinical data were collected for the T1DM patients. All participants completed a questionnaire regarding possible BPA exposures. Multivariate logistic regression analysis was used to estimate the adjusted odds ratio for T1DM.

RESULTS

Seventy-five T1DM patients and 113 age-matched controls were included in the study. The mean age for T1DM and control groups were 14.8 ± 5.7 and 14.4 ± 6.2 years, respectively. The T1DM group had a significantly higher median (interquartile range) level of adjusted urinary BPA compared to the control (31.50 [7.87, 69.45] vs 10.1 [0, 54.01] μg/g creatinine, P = 0.02). Urinary BPA of 17 μg/g creatinine or more was significantly associated with TIDM, with adjusted odds ratio (95% Confident interval, CI) of 2.38 (1.27, 4.44), P = 0.006.

CONCLUSIONS

Higher urinary BPA level is one of the possible risk factors for T1DM.

The effect of reduction measures on concentrations of hazardous semivolatile organic compounds in indoor air and dust of Swedish preschools

Young children spend a substantial part of their waking time in preschools. It is therefore important to reduce the load of hazardous semivolatile organic compounds (SVOCs) in the preschools' indoor environment. The presence and levels of five SVOC groups were evaluated (1) in a newly built preschool, (2) before and after renovation of a preschool, and (3) in a preschool where SVOC-containing articles were removed. The new building and the renovation were performed using construction materials that were approved with respect to content of restricted chemicals. SVOC substance groups were measured in indoor air and settled dust and included phthalates and alternative plasticizers, organophosphate esters (OPEs), brominated flame retardants, and bisphenols. The most abundant substance groups in both indoor air and dust were phthalates and alternative plasticizers and OPEs. SVOC concentrations were lower or of the same order of magnitude as those reported in comparable studies. The relative Cumulative Hazard Quotient (HQ_cum ) was used to assess the effects of the different reduction measures on children's SVOC exposure from indoor air and dust in the preschools. HQ_cum values were low (1.0-6.1%) in all three preschools and decreased further after renovation and article substitution. The SVOCs concentrations decreased significantly more in the preschool renovated with the approved building materials than in the preschool where the SVOC-containing articles were removed.

Maternal di-(2-ethylhexyl) phthalate exposure alters hepatic insulin signal transduction and glucoregulatory events in rat F1 male offspring

Di-(2-ethylhexyl) phthalate (DEHP) is a commonly used plasticizer with endocrine disrupting properties. Its widespread use resulted in constant human exposure including fetal development and postnatal life. Epidemiological and experimental data have shown that DEHP has a negative influence on glucose homeostasis. However, the evidence regarding the effect of maternal DEHP exposure on hepatic glucose homeostasis is scarce. Hence, we investigated whether DEHP exposure during gestation and lactation disrupts glucose homeostasis in the rat F₁ male offspring at adulthood. Pregnant rats were divided into three groups and administered with DEHP (10 and 100 mg/kg/day) or olive oil from gestational day 9 to postnatal day 21 (lactation period) through oral gavage. DEHP-exposed offspring exhibited hyperglycemia, impaired glucose and insulin tolerances along with hyperinsulinemia at postnatal day 80. DEHP exposure significantly reduced the levels of insulin signaling molecules such as insulin receptors, IRS1, Akt and its phosphorylated forms. GSK3β and FoxO1 proteins increased in DEHP-exposed groups whereas its phosphorylated forms decreased. Treated groups showed decreased glycogen synthase activity and glycogen concentration. Glucose-6-phosphatase and phosphoenolpyruvate carboxykinase mRNA level and enzyme activity increased in DEHP-treated groups. The interaction between FoxO1-glucose-6-phosphatase and FoxO1-phosphoenolpyruvate carboxykinase was also increased. This study suggests that DEHP exposure impairs insulin signal transduction and alters glucoregulatory events leading to the development of type 2 diabetes in F₁ male offspring.

The LIFE PERSUADED project approach on phthalates and bisphenol A biomonitoring in Italian mother-child pairs linking exposure and juvenile diseases

Phthalates and bisphenol A (BPA), plasticizers used in several products of daily life, are considered as endocrine disrupters, therefore children exposure is particularly relevant. The LIFE PERSUADED project aims to define the following: (a) the evaluation of internal levels of DEHP's metabolites and BPA in Italian children and their mothers, (b) the association of the exposure with puberty development and obesity diseases, and (c) the effects of exposure in juvenile in vivo model. The cross-sectional study has involved 2160 mother-child pairs, including males and females, children and adolescents, from urban and rural areas of North, Center, and South Italy. A structured questionnaire and a food diary are designed to evaluate the association between lifestyle variables potentially related to DEHP/BPA exposure and internal levels, through univariate and multivariate analyses. Two pilot case-control studies are carried out on idiopathic premature thelarche and precocious puberty (30 girls each group, aged 2-7 years) and idiopathic obesity (30 boys and 30 girls, aged 6-10 years), matched to healthy controls. BPA and DEHP's metabolites are analyzed in urine samples from all recruited subjects. Clinical and toxicological biomarkers are evaluated in serum of case-control subjects. Moreover, the toxicity study is carried out in a juvenile rodent model exposed to mixtures of BPA and DEHP at dose levels recorded in children population. The scientific results of LIFE PERSUADED will contribute to risk assessment of BPA and DEHP.

The role of pollutants in type 2 diabetes mellitus (T2DM) and their prospective impact on phytomedicinal treatment strategies

Type 2 diabetes mellitus (T2DM) is the most common form of diabetes and it is characterized by high blood sugar and abnormal sera lipid levels. Although the specific reasons for the development of these abnormalities are still not well understood, traditionally, genetic and lifestyle behavior have been reported as the leading causes of this disease. In the last three decades, the number of diabetic patients has drastically increased worldwide, with current statistics suggesting the number is to double in the next two decades. To combat this incurable ailment, orthodox medicines, to which economically disadvantaged patients have minimal access to, have been used. Thus, a considerable amalgamation of medicinal plants has recently been proven to possess therapeutic capabilities to manage T2DM, and this has prompted studies primarily focusing on the healing aspect of these plants, and ultimately, their commercialization. Hence, this review aims to highlight the potential threat of pollutants, i.e., polyfluoroalkyl compounds (PFCs), endocrine disrupting chemicals (EDCs) and heavy metals, to medicinal plants, and their prospective impact on the phytomedicinal therapy strategies for T2DM. It is further suggested that auxiliary research be undertaken to better comprehend the factors that influence the uptake of these compounds by these plants. This should include a comprehensive risk assessment of phytomedicinal products destined for the treatment of T2DM. Regulations that control the use of PFC-precursors in certain developing countries are also long overdue.

Bisphenol A is not associated with a 5-year incidence of type 2 diabetes: a prospective nested case-control study

AIMS

The relationship between bisphenol A (BPA) and diabetes remains controversial. This study aims to investigate whether serum BPA level could predict the 5-year incidence of type 2 diabetes (T2D).

METHODS

A nested case-control study was performed among Chinese who participated in the environment, inflammation and metabolic diseases study (2008-2013). Of the 3510 subjects who were free of diabetes, 232 subjects developed diabetes during the 5-year follow-up. Cases and controls were matched for age and gender by a ratio of 1:1. Homoeostasis model assessment was used to estimate basal β-cell function (HOMA-β) and insulin resistance (HOMA-IR). Participants were stratified into tertiles based on low, median and high baseline serum BPA levels. Regression models were used to analyze the relationship between serum BPA concentration and the incidence of T2D.

RESULTS

At baseline, no significant difference in serum BPA concentration was observed between patients with T2D and controls [1.3 (0.3, 3.7) vs. 1.6 (0.4, 3.9) μmol/L, P = 0.199]; serum BPA concentration was positively associated with fasting plasma glucose (r = 0.27, P < 0.001); however, neither HOMA-β nor HOMA-IR correlated with serum BPA concentration. During the follow-up, baseline BPA levels could not predict the 5-year T2D incidence, whether or not adjusted for the potential confounders such as body mass index and blood pressure. [Low BPA tertile was the reference, OR 0.66 (95% CI 0.30, 1.44) for median, OR 0.93 (95% CI 0.41, 2.13) for high.] CONCLUSION: BPA is not associated with a 5-year T2D incidence. These data do not support previous cross-sectional study that BPA exerted a detrimental effect on glucose metabolism.

Adipose Tissue as a Site of Toxin Accumulation

We examine the role of adipose tissue, typically considered an energy storage site, as a potential site of toxicant accumulation. Although the production of most persistent organic pollutants (POPs) was banned years ago, these toxicants persist in the environment due to their resistance to biodegradation and widespread distribution in various environmental forms (e.g., vapor, sediment, and water). As a result, human exposure to these toxicants is inevitable. Largely due to their lipophilicity, POPs bioaccumulate in adipose tissue, resulting in greater body burdens of these environmental toxicants with obesity. POPs of major concern include polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and furans (PCDDs/PCDFs), and polybrominated biphenyls and diphenyl ethers (PBBs/PBDEs), among other organic compounds. In this review, we (i) highlight the physical characteristics of toxicants that enable them to partition into and remain stored in adipose tissue, (ii) discuss the specific mechanisms of action by which these toxicants act to influence adipocyte function, and (iii) review associations between POP exposures and the development of obesity and diabetes. An area of controversy relates to the relative potential beneficial versus hazardous health effects of toxicant sequestration in adipose tissue. © 2017 American Physiological Society. Compr Physiol 7:1085-1135, 2017.

Bisphenol A and the risk of cardiometabolic disorders: a systematic review with meta-analysis of the epidemiological evidence

Bisphenol A (BPA) is suspected to be associated with several chronic metabolic diseases. The aim of the present study was to review the epidemiological literature on the relation between BPA exposure and the risk of cardiometabolic disorders. PubMed and Embase databases were searched up to August 2014 by two independent investigators using standardized subject terms. We included observational studies (cohort, case-control and cross-sectional studies) carried out in children or adults, measuring urinary BPA (uBPA), including at least 100 participants and published in English. The health outcomes of interest were diabetes, hyperglycemia, measures of anthropometry, cardiovascular disease (CVD) and hypertension. Data were extracted and meta-analyzed when feasible, using a random-effects model. Thirty-three studies with sample size ranging from 239 to 4811 met the inclusion criteria, including five with a prospective design. Twelve studies reported on diabetes or hyperglycemia, 16 on anthropometry, 6 on CVD and 3 on hypertension. Evidence for a positive association between uBPA concentrations and diabetes, overweight, obesity, elevated waist circumference (WC), CVD and hypertension was found in 7/8, 2/7, 6/7, 5/5, 4/5 and 2/3 of the cross-sectional studies, respectively. We were able to conduct outcome-specific meta-analyses including 12 studies. When comparing the highest vs. the lowest uBPA concentrations, the pooled ORs were 1.47 (95% CI: 1.21-1.80) for diabetes, 1.21 (95% CI: 0.98-1.50) for overweight, 1.67 (95% CI: 1.41-1.98) for obesity, 1.48 (95% CI: 1.25-1.76) for elevated WC, and 1.41 (95% CI: 1.12-1.79) for hypertension. Moreover, among the five prospective studies, 3 reported significant findings, relating BPA exposure to incident diabetes, incident coronary artery disease, and weight gain. To conclude, there is evidence from the large body of cross-sectional studies that individuals with higher uBPA concentrations are more likely to suffer from diabetes, general/abdominal obesity and hypertension than those with lower uBPA concentrations. Given the potential importance for public health, prospective cohort studies with proper adjustment for dietary characteristics and identification of critical windows of exposure are urgently needed to further improve knowledge about potential causal links between BPA exposure and the development of chronic disease.