High long-term cortisol levels, measured in scalp hair, are associated with a history of cardiovascular disease.

"Abstract

BACKGROUND:

Stress is associated with an increased incidence of cardiovascular disease. The impact of chronic stress on cardiovascular risk has been studied by measuring cortisol in serum and saliva, which are measurements of only 1 time point. These studies yielded inconclusive results. The measurement of cortisol in scalp hair is a novel method that provides the opportunity to measure long-term cortisol exposure. Our aim was to study whether long-term cortisol levels, measured in scalp hair, are associated with cardiovascular diseases.

METHODS:

A group of 283 community-dwelling elderly participants were randomly selected from a large population-based cohort study (median age, 75 y; range, 65-85 y). Cortisol was measured in 3-cm hair segments, corresponding roughly with a period of 3 months. Self-reported data concerning coronary heart disease, stroke, peripheral arterial disease, diabetes mellitus, and other chronic noncardiovascular diseases were collected.

RESULTS:

Hair cortisol levels were significantly lower in women than in men (21.0 vs 26.3 pg/mg hair; P < .001). High hair cortisol levels were associated with an increased cardiovascular risk (odds ratio, 2.7; P = .01) and an increased risk of type 2 diabetes mellitus (odds ratio, 3.2; P = .04). There were no associations between hair cortisol levels and noncardiovascular diseases.

CONCLUSIONS:

Elevated long-term cortisol levels are associated with a history of cardiovascular disease. The increased cardiovascular risk we found is equivalent to the effect of traditional cardiovascular risk factors, suggesting that long-term elevated cortisol may be an important cardiovascular risk factor."

http://www.ncbi.nlm.nih.gov/pubmed/23596141

The metabolic response to ingested glycine.

Abstract

"BACKGROUND:

The metabolic effects of dietary protein are complex. In persons with type 2 diabetes, protein ingestion results in little or no increase in plasma glucose concentrations but a stimulation of insulin and glucagon secretion. Furthermore, when protein is ingested with glucose, a synergistic effect on insulin secretion is observed. The most potent protein is gelatin, which consists of 30% glycine residues.

OBJECTIVE:

The objective of the present study was to determine whether glycine per se stimulates insulin secretion or reduces the glucoseresponse when ingested with glucose.

DESIGN:

Nine healthy subjects were tested on 4 separate occasions. Plasma glucose, insulin, glucagon, and glycine concentrations were measured at various times during a 2-h period after the ingestion of 1 mmol glycine/kg lean body mass, 25 g glucose, 1 mmol glycine/kg lean body mass + 25 g glucose, or water only, given in random order.

RESULTS:

Plasma concentrations of glycine and glucagon were elevated after the ingestion of glycine, as expected. The serum insulin concentration also was slightly elevated after the ingestion of glycine alone. When glycine was ingested with glucose, the plasma glucose area response was attenuated by > 50% compared with the response after the ingestion of glucose alone. The dynamics of the insulin response after the ingestion ofglycine plus glucose were modestly different from those after the ingestion of glucose alone, but the area response was not significantly different.

CONCLUSION:

The data are compatible with the hypothesis that oral glycine stimulates the secretion of a gut hormone that potentiates the effect of insulin on glucose removal from the circulation."

[full text]

Toxic effects of the easily avoidable phthalates and parabens.

Abstract

"Some environmental toxins like DDT and other chlorinated compounds accumulate in the body because of their fat-soluble nature. Other compounds do not stay long in the body, but still cause toxic effects during the time they are present. For serious health problems to arise, exposure to these rapidly-clearing compounds must occur on a daily basis. Two such classes of compounds are the phthalate plasticizers and parabens, both of which are used in many personal care products, some medications, and even foods and food preservation. The phthalates are commonly found in foods and household dust. Even though they have relatively short half-lives in humans, phthalates have been associated with a number of serious health problems, including infertility, testicular dysgenesis, obesity, asthma, and allergies, as well as leiomyomas and breast cancer. Parabens, which can be dermally absorbed, are present in many cosmetic products, including antiperspirants. Their estrogenicity and tissue presence are a cause for concern regarding breast cancer. Fortunately, these compounds are relatively easy to avoid and such steps can result in dramatic reductions of urinary levels of these compounds."

[full text] 

Evaluation of a Screening System for Obesogenic Compounds: Screening of Endocrine Disrupting Compounds and Evaluation of the PPAR Dependency of the Effect

Abstract

"Recently the environmental obesogen hypothesis has been formulated, proposing a role for endocrine disrupting compounds (EDCs) in the development of obesity. To evaluate this hypothesis, a screening system for obesogenic compounds is urgently needed. In this study, we suggest a standardised protocol for obesogen screening based on the 3T3-L1 cell line, a well-characterised adipogenesis model, and direct fluorescent measurement using Nile red lipid staining technique. In a first phase, we characterised the assay using the acknowledged obesogens rosiglitazone and tributyltin. Based on the obtained dose-response curves for these model compounds, a lipid accumulation threshold value was calculated to ensure the biological relevance and reliability of statistically significant effects. This threshold based method was combined with the well described strictly standardized mean difference (SSMD) method for classification of non-, weak- or strong obesogenic compounds. In the next step, a range of EDCs, used in personal and household care products (parabens, musks, phthalates and alkylphenol compounds), were tested to further evaluate the obesogenicity screening assay for its discriminative power and sensitivity. Additionally, the peroxisome proliferator activated receptor γ (PPARγ) dependency of the positive compounds was evaluated using PPARγ activation and antagonist experiments. Our results showed the adipogenic potential of all tested parabens, several musks and phthalate compounds and bisphenol A (BPA). PPARγ activation was associated with adipogenesis for parabens, phthalates and BPA, however not required for obesogenic effects induced by Tonalide, indicating the role of other obesogenic mechanisms for this compound."

[full text]