Assessment of the value of measuring soluble fms-like tyrosine kinase-1 and placental growth factor levels following administration of tadalafil to treat fetal growth restriction

PURPOSE

The aim of this study was to measure the blood levels of soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) before and after tadalafil treatment in patients with fetal growth restriction.

MATERIALS AND METHODS

Maternal blood was collected from 13 women before and 2 weeks after tadalafil administration in the TADAFER II trial. The tadalafil treatment was conducted in addition to the conventional FGR treatment. As a control, maternal blood was also collected from 11 women before and 2 weeks after conventional treatment for fetal growth restriction. Blood sFlt-1 and PlGF were measured and the sFlt-1/PlGF ratio was calculated. Student's t-test was used to statistically analyze differences in the sFlt-1 and PlGF levels, and in the sFlt-1/PlGF ratios.

RESULTS

In both treatment groups, the levels of sFlt-1 and PlGF before and after treatment were not significantly different from each other. The sFlt-1/PlGF ratio was 2.0 ± 1.0 before and 17.6 ± 11.3 after treatment in the control group (p=.04). The sFlt-1/PlGF ratio was 2.2 ± 1.1 before and 22.2 ± 10.6 after tadalafil treatment in the tadalafil group (p=.06). The sFlt-1/PlGF ratios before and after tadalafil treatment were significantly increased in the control group. In both treatment groups, the sFlt-1/PlGF ratios before and after treatment were less than 38.

CONCLUSIONS

We conclude that the levels of sFlt-1 and PlGF were not significantly different as a result of tadalafil treatment. Further studies are needed to understand the mechanism of action of tadalafil in the treatment of fetal growth restriction.

Effects of short-term DHEA intake on hormonal responses in young recreationally trained athletes: modulation by gender

BACKGROUND

Dehydroepiandrosterone (DHEA) figures on the World Anti-Doping Agency list of prohibited substances in sport because it is assumed that athletes expect a significant increase in testosterone through DHEA administration. The literature on the hormonal effects of DHEA intake nevertheless appears to be very scant in healthy young subjects, especially women.

PURPOSE

We examined the effects of DHEA on adrenal and gonadal hormones, IGF1 and free T3 in healthy young male and female recreationally trained volunteers.

METHODS

The study followed a double-blind, randomized-order crossover design. Lean healthy young men (n = 10) and women (n = 11), with all women using oral contraceptives, were treated daily with 100 mg of DHEA and placebo for 4 weeks. DHEA, DHEA-sulfate (DHEA-S), androstenedione, total testosterone (Tes), dihydrotestosterone (DHT), SHBG, estrone, cortisol, IGF1, and free T3 were measured before, in the middle and at the end of each treatment, as were blood glucose, liver transaminases and lipid status.

RESULTS

We observed a significant increase in DHEA, DHEA-S, androstenedione, Tes, DHT, and estrone in both men and women in the middle and at the end of DHEA treatment, but the increase in Tes was more marked in women (p < 0.001) than men (p < 0.05). No changes were found in the other parameters, irrespective of gender.

CONCLUSION

In young athletes, DHEA administration induces significant blood hormonal changes, some modulated by gender, which can be used as biomarkers of doping.

Analytical progresses of the World Anti-Doping Agency Olympic laboratories: a 2016 update from London to Rio

The 2016 Olympic and Paralympic Games, the biggest event in human sports, was held in Rio de Janeiro with more than 10,500 athletes from 206 countries over the world competing for the highest of sports honors, an Olympic medal. With the hope that the Olympic ideal accompanies all aspects of the XXXI Olympiad, WADA accredited antidoping laboratories use the spearhead of analytical technology as a powerful tool in the fight against doping. This review summarizes the main analytical developments applied in antidoping testing methodology combined with the main amendments on the WADA regulations regarding analytical testing starting from the 2012 London Olympics until the 2016 Olympic Games in Rio de Janeiro.

Pathology consultation on human chorionic gonadotropin testing for pregnancy assessment

OBJECTIVES

To provide clarity on the use of qualitative and quantitative human chorionic gonadotropin (hCG) tests for the assessment of pregnancy.

METHODS

A case scenario and a brief review of the relevant literature describing clinical and analytical considerations regarding hCG testing are presented.

RESULTS

In pregnancy, hCG is nearly always detectable in serum and urine within 16 days after ovulation. Serial hCG testing is valuable in the evaluation of suspected ectopic pregnancy. hCG assays vary in their analytical specificity, and qualitative tests may be less analytically sensitive than claimed. Erroneous hCG test results can occur for several reasons.

CONCLUSIONS

hCG assays are reliable diagnostic tests for pregnancy assessment, but a clear understanding of their limitations is necessary for appropriate result interpretation.

Current trends in mass spectrometry of peptides and proteins: Application to veterinary and sports-doping control

Detection of misuse of peptides and proteins as growth promoters is a major issue for sport and food regulatory agencies. The limitations of current analytical detection strategies for this class of compounds, in combination with their efficacy in growth-promoting effects, make peptide and protein drugs highly susceptible to abuse by either athletes or farmers who seek for products to illicitly enhance muscle growth. Mass spectrometry (MS) for qualitative analysis of peptides and proteins is well-established, particularly due to tremendous efforts in the proteomics community. Similarly, due to advancements in targeted proteomic strategies and the rapid growth of protein-based biopharmaceuticals, MS for quantitative analysis of peptides and proteins is becoming more widely accepted. These continuous advances in MS instrumentation and MS-based methodologies offer enormous opportunities for detection and confirmation of peptides and proteins. Therefore, MS seems to be the method of choice to improve the qualitative and quantitative analysis of peptide and proteins with growth-promoting properties. This review aims to address the opportunities of MS for peptide and protein analysis in veterinary control and sports-doping control with a particular focus on detection of illicit growth promotion. An overview of potential peptide and protein targets, including their amino acid sequence characteristics and current MS-based detection strategies is, therefore, provided. Furthermore, improvements of current and new detection strategies with state-of-the-art MS instrumentation are discussed for qualitative and quantitative approaches.

An ultrasensitive method for the quantitation of active and inactive GLP-1 in human plasma via immunoaffinity LC–MS/MS

Background: Measuring endogenous levels of incretin hormones, like GLP-1, is critical in the development of antidiabetic compounds. However, the assays used to measure these molecules often have analytical issues. Results: We have developed an ultrasensitive, highly-selective immunoaffinity LC–MS/MS (IA LC–MS/MS) assay capable of quantitating endogenous levels of active (7–36 amide) and inactive (9–36 amide) GLP-1 in human plasma. We performed fit-for-purpose validation of the assay by assessing the following assay performance characteristics: inter-assay precision, sensitivity, spike recovery, dilution linearity, absolute recovery, matrix effect, immunoprecipitation efficiency, and food effect. Conclusion: We have developed a robust analytical method for the quantitation of endogenous active and inactive GLP-1 in human plasma. In addition, we employed this method to measure the typical changes in GLP-1 levels after food intake. The sensitivity of this assay is better than another LC–MS/MS GLP-1 assay previously reported and many commercially available immunoassays. This important analytical tool could be used to qualify and/or harmonize the different immunoassays used for the quantitation of GLP-1.

Standardization of hormone determinations

Standardization of hormone determinations is important because it simplifies interpretation of results and facilitates the use of common reference values for different assays. Progress in standardization has been achieved through the introduction of more homogeneous hormone standards for peptide and protein hormones. However, many automated methods for determinations of steroid hormones do not provide satisfactory result. Isotope dilution-mass spectrometry (ID-MS) has been used to establish reference methods for steroid hormone determinations and is now increasingly used for routine determinations of steroids and other low molecular weight compounds. Reference methods for protein hormones based on MS are being developed and these promise to improve standardization.