Plasma proteins elevated in severe asthma despite oral steroid use and unrelated to Type-2 inflammation

Rationale

Asthma phenotyping requires novel biomarker discovery.

Objectives

To identify plasma biomarkers associated with asthma phenotypes by application of a new proteomic panel to samples from two well-characterised cohorts of severe (SA) and mild-to-moderate (MMA) asthmatics, COPD subjects and healthy controls (HCs).

Methods

An antibody-based array targeting 177 proteins predominantly involved in pathways relevant to inflammation, lipid metabolism, signal transduction and extracellular matrix was applied to plasma from 525 asthmatics and HCs in the U-BIOPRED cohort, and 142 subjects with asthma and COPD from the validation cohort BIOAIR. Effects of oral corticosteroids (OCS) were determined by a 2-week, placebo-controlled OCS trial in BIOAIR, and confirmed by relation to objective OCS measures in U-BIOPRED.

Results

In U-BIOPRED, 110 proteins were significantly different, mostly elevated, in SA compared to MMA and HCs. 10 proteins were elevated in SA versus MMA in both U-BIOPRED and BIOAIR (alpha-1-antichymotrypsin, apolipoprotein-E, complement component 9, complement factor I, macrophage inflammatory protein-3, interleukin-6, sphingomyelin phosphodiesterase 3, TNF receptor superfamily member 11a, transforming growth factor-β and glutathione S-transferase). OCS treatment decreased most proteins, yet differences between SA and MMA remained following correction for OCS use. Consensus clustering of U-BIOPRED protein data yielded six clusters associated with asthma control, quality of life, blood neutrophils, high-sensitivity C-reactive protein and body mass index, but not Type-2 inflammatory biomarkers. The mast cell specific enzyme carboxypeptidase A3 was one major contributor to cluster differentiation.

Conclusions

The plasma proteomic panel revealed previously unexplored yet potentially useful Type-2-independent biomarkers and validated several proteins with established involvement in the pathophysiology of SA.

Application of new proteomic panel in two established European asthma cohorts identifies plasma proteins associated with disease severity independently of Type-2 inflammation, suggesting potentially useful novel biomarkers and therapeutic targets.https://bit.ly/3jtTq5m

Re-evaluation of combined ((ES/EG)/(TS/TG)) ratio as a marker of testosterone intake in men

To detect doping with pseudo-endogenous anabolic steroids in sports, a urinary steroid profile with glucuronidated plus unconjugated androgens is used. In addition to analyze androgen glucuronide metabolites, it can be of interest to also include sulfate metabolites in the urinary steroid profile. The combined ratios of epitestosterone sulfate/epitestosterone glucuronide to the ratios of testosterone sulfate/testosterone glucuronide ((ES/EG)/(TS/TG)) have previously been investigated as a complementary biomarker for testosterone doping. In this restudy, the aim was to evaluate this biomarker in a larger study sample population. A single dose of 500-mg testosterone enanthate was administered to 54 healthy male volunteers. Urine was collected prior to (Day 0) administration and throughout 15 days and analyzed for the sulfate and glucuronide conjugates of testosterone and epitestosterone. The results show that the combined ratio increased to a larger extent than the traditional T/E ratio in all subjects. This increase was independent on UGT2B17 gene polymorphism. Moreover, a delayed peak of the combined ratio was observed in ~60% of the participants. The results confirm that complementary analyses of the sulfate metabolites may be a useful approach to detect testosterone doping in men.

Medication Adherence in Patients With Severe Asthma Prescribed Oral Corticosteroids in the U-BIOPRED Cohort

BACKGROUND

Although estimates of suboptimal adherence to oral corticosteroids in asthma range from 30% to 50%, no ideal method for measurement exists; the impact of poor adherence in severe asthma is likely to be particularly high.

RESEARCH QUESTIONS

What is the prevalence of suboptimal adherence detected by self-reporting and direct measures? Is suboptimal adherence associated with disease activity?

STUDY DESIGN AND METHODS

Data were included from individuals with severe asthma taking part in the U-BIOPRED (Unbiased Biomarkers for the Prediction of Respiratory Disease Outcomes) study and prescribed daily oral corticosteroids. Participants completed the Medication Adherence Report Scale, a five-item questionnaire used to grade adherence on a scale from 1 to 5, and provided a urine sample for analysis of prednisolone and metabolites by liquid chromatography-mass spectrometry.

RESULTS

Data from 166 participants were included in this study: mean (SD) age, 54.2 (± 11.9) years; FEV₁, 65.1% (± 20.5%) predicted; female, 58%; 37% completing the Medication Adherence Report Scale reported suboptimal adherence; and 43% with urinary corticosteroid data did not have detectable prednisolone or metabolites in their urine. Good adherence by both methods was detected in 49 of the 142 (35%) of participants in whom both methods were performed; adherence detection did not match between methods in 53%. Self-reported high adherers had better asthma control and quality of life, whereas directly measured high adherers had lower blood eosinophil levels.

INTERPRETATION

Low adherence is a common problem in severe asthma, whether measured directly or self-reported. We report poor agreement between the two methods, suggesting some disassociation between self-assessment of medication adherence and regular oral corticosteroid use, which suggests that each approach may provide complementary information in clinical practice.

Urinary Leukotriene E4 and Prostaglandin D2 Metabolites Increase in Adult and Childhood Severe Asthma Characterized by Type 2 Inflammation. A Clinical Observational Study

Rationale: New approaches are needed to guide personalized treatment of asthma.Objectives: To test if urinary eicosanoid metabolites can direct asthma phenotyping.Methods: Urinary metabolites of prostaglandins (PGs), cysteinyl leukotrienes (CysLTs), and isoprostanes were quantified in the U-BIOPRED (Unbiased Biomarkers for the Prediction of Respiratory Diseases Outcomes) study including 86 adults with mild-to-moderate asthma (MMA), 411 with severe asthma (SA), and 100 healthy control participants. Validation was performed internally in 302 participants with SA followed up after 12-18 months and externally in 95 adolescents with asthma.Measurement and Main Results: Metabolite concentrations in healthy control participants were unrelated to age, body mass index, and sex, except for the PGE₂ pathway. Eicosanoid concentrations were generally greater in participants with MMA relative to healthy control participants, with further elevations in participants with SA. However, PGE₂ metabolite concentrations were either the same or lower in male nonsmokers with asthma than in healthy control participants. Metabolite concentrations were unchanged in those with asthma who adhered to oral corticosteroid treatment as documented by urinary prednisolone detection, whereas those with SA treated with omalizumab had lower concentrations of LTE₄ and the PGD₂ metabolite 2,3-dinor-11β-PGF_2α. High concentrations of LTE₄ and PGD₂ metabolites were associated with lower lung function and increased amounts of exhaled nitric oxide and eosinophil markers in blood, sputum, and urine in U-BIOPRED participants and in adolescents with asthma. These type 2 (T2) asthma associations were reproduced in the follow-up visit of the U-BIOPRED study and were found to be as sensitive to detect T2 inflammation as the established biomarkers.Conclusions: Monitoring of urinary eicosanoids can identify T2 asthma and introduces a new noninvasive approach for molecular phenotyping of adult and adolescent asthma.Clinical trial registered with www.clinicaltrials.gov (NCT01976767).

Digit Ratio (2D:4D) and Physical Performance in Female Olympic Athletes

Background: The second to fourth digit ratio (2D:4D ratio) is suggested to be a negative correlate of prenatal testosterone. Little is known about the role of the 2D:4D ratio in relation to serum and urinary androgens for physical performance in female athletes. We aimed to compare the 2D:4D ratio in female Olympic athletes with sedentary controls, and to investigate the 2D:4D ratio in relation to serum and urinary androgens and physical performance in the athletes. Methods: This cross-sectional study included 104 Swedish female Olympic athletes participating in power, endurance and technical sports and 117 sedentary controls. The 2D:4D ratio was calculated using direct digit measurements. Serum androgens and urinary androgen metabolites were analyzed by liquid chromatography-tandem mass spectrometry. The athletes performed standardized physical performance tests and body composition was established by dual-energy X-ray absorptiometry. Results: The 2D:4D ratio was significantly lower in the athletes compared with controls although serum testosterone levels were comparable between groups and within normal reference values. The 2D:4D ratio correlated negatively with urinary levels of testosterone glucuronide and 5α- and 5βAdiol-17G, whereas there were no correlations to serum androgen levels. Furthermore, the 2D:4D ratio correlated negatively with strength tests and positively with 3,000-meter running in the athletes. Conclusion: Female Olympic athletes had a lower 2D:4D ratio, possibly reflecting a higher prenatal androgen exposure, than sedentary controls. Furthermore, the 2D:4D ratio was related to urinary levels of androgen metabolites and physical performance in the athletes but not to serum androgen levels. It is suggested that the 2D:4D ratio could reflect androgen metabolism and may be of importance for sporting success in female athletes.

Pregnancy-Induced Perturbation of Urinary Androgenic Steroid Disposition

Objective

To investigate the excretion and conjugation profile of testosterone (T), Epitestosterone (EpiT), and other androgen metabolites in different phases of pregnancy and postpregnancy as a reflection of the “androgenic exposure.”

Design

Consecutive recruitment of pregnant women.

Setting

Maternity outpatient low-risk pregnancy clinic.

Patients

Seventy-seven pregnant women.

Interventions

Collection of urine for analyses of sulfate (S) and glucuronide (G) conjugates and metabolic ratios of androgens and androgen metabolites using liquid chromatography-tandem mass spectrometry.

Main Outcome Measures

Excretion profiles and metabolic ratios of G and S conjugates of T, EpiT, dehydroepiandrosterone (DHEA), androsterone (A), etiocholanolone (Etio), and dihydrotestosterone in relation to trimester and postpartum, body mass index, fetal sex, and ethnicity.

Results

T-S excretion increased significantly between the second and third trimester, whereas excretion of T-G did not change. In contrast, both conjugates of EpiT increased markedly, more so for the S-(17-fold) than the G-conjugate (1.6-fold). The preference for S over G conjugation was conspicuous for EpiT and DHEA (S/G ratio 2.1 and 4.7, respectively, in the third trimester), whereas the reverse was true for T, A, and Etio (S/G 0.6, 0.13, and 0.11, respectively).

Conclusions

Pregnancy influences the androgen excretion profile, with the most profound change being an increase in EpiT excretion throughout the trimesters. EpiT may modulate the effect of T, but its exact role during pregnancy is not known. There were marked differences in the S/G conjugate ratios between androgens upstream and downstream from T in the metabolic network. These results are interesting to compare with the androgen disposition in women with endocrine disorders or abuse of steroids.

Testosterone challenge and androgen receptor activity in relation to UGT2B17 genotypes

BACKGROUND

We investigated the androgen receptor (AR) bioluminescense response in serum and urine before and after testosterone challenge in different genotypes of the UGT2B17 enzyme, which catalyses testosterone glucuronidation.

MATERIAL AND METHODS

The androgen receptor activity was determined using a yeast-based bioluminescence assay. The androgens were analysed using LC-MS/MS, and the individuals were genotyped for UGT2B17 deletion polymorphism using real-time polymerase chain reaction.

RESULTS

The serum concentrations of testosterone and dihydrotestosterone (DHT) were markedly elevated on days 2 and 4 and were still above baseline on day 15 after a dose of 500 mg testosterone enanthate. The androgenic activity in serum increased in parallel and correlated with the hormone concentrations and remained above baseline on day 15. The urinary androgenic activity increased 4-5-fold and was closely related to the unconjugated testosterone and independent of the UGT2B17 genotype.

CONCLUSIONS

The AR assay may serve as a complement to the urinary testosterone/epitestosterone (T/E) doping test, because this is profoundly influenced by the UGT2B17 deletion polymorphism. It may also be useful for detection of other illicit androgens in sports, or in the society, or for monitoring and diagnostics of androgen-related disorders.

SULT2A1 Gene Copy Number Variation is Associated with Urinary Excretion Rate of Steroid Sulfates

Human cytosolic sulfotransferases (SULT) 2A1 is the main enzyme involved in the sulfate conjugation of dehydroepiandrosterone, a weak androgen, and the main androgen precursor, whereas estrogens are mainly conjugated by SULT1A1. Here we have identified a copy number variation (CNV) polymorphism in the SULT2A1 gene in a Swedish population including healthy men (N = 30). Moreover, the CNV of SULT1A1 and SULT2A1 was further characterized in relation to urinary levels of androgen sulfate metabolites before and after an intramuscular dose of 500 mg testosterone enanthate. Individuals expressing two or more CNVs excrete 80 and 40% higher levels of DHEAS (p = 0.02) and androsteroneS (p = 0.01), respectively as compared to individuals with one gene copy. The mean area under the urine concentration time-curve from time 0 (prior to the administration of 500 mg testosterone) to 15 days post dose values were 80% higher for DHEAS (p = 0.046) and testosteroneS (p = 0.019) in individuals with two and three SULT2A1 gene copies as compared to individuals with one gene copy. The SULT1A1 CNV on the other hand did not affect the sulfation activity toward the androgens. In conclusion our results indicate that functional CNV polymorphisms in SULT2A1 and SULT1A1 are common in a Swedish population and that SULT2A1 CNV is associated with the urinary concentrations of androgen sulfate metabolites.

Non-steroidal anti-inflammatory drugs do not influence the urinary testosterone/epitestosterone glucuronide ratio

The UDP Glucuronosyl Transferase (UGT) enzymes are important in the pharmacokinetics, and conjugation, of a variety of drugs including non-steroidal anti-inflammatory drugs (NSAIDs) as well as anabolic androgenic steroids (AAS). Testosterone glucuronidation capacity is strongly associated with a deletion polymorphism in the UGT2B17 gene. As the use of high doses of NSAIDs has been observed in athletes there is a risk for a drug-drug interaction that may influence the doping tests for AAS. In vitro studies show inhibitory potential on UGT2B7, 2B15, and 2B17 enzymes by NSAIDs. The aim of this study was to investigate if concomitant use of NSAIDs and a single dose of testosterone enanthate would affect the excretion rate of testosterone and epitestosterone glucuronide (TG and EG) as well as the T/E ratio, thereby affecting the outcome of the testosterone doping test. The study was designed as an open, randomized, cross-over study with subjects being their own control. The 23 male healthy volunteers, with either two, one or no allele (ins/ins, ins/del, or del/del) of the UGT2B17 gene, received the maximum recommended dose of NSAID (Ibuprofen or Diclofenac) for 6 days. On day three, 500 mg of testosterone enanthate was administered. Spot urine samples were collected for 17 days. After a wash-out period of 4 months the volunteers received 500 mg testosterone enanthate only, with subsequent spot urine collection for 14 days. The glucuronides of testosterone and epitestosterone were quantified. NSAIDs did not affect the excretion of TG or EG before the administration of testosterone. The concomitant use of NSAIDs and testosterone slightly increased the TG excretion while the EG excretion was less suppressed compared to testosterone use only. The effects of the NSAIDs on the TG and EG excretion did not differ between the UGT2B17 genotype groups. In conclusion, the outcome of testosterone doping tests does not seem to be affected by the use of NSAIDs.

Androgen sulfation in healthy UDP-glucuronosyl transferase 2B17 enzyme-deficient men

CONTEXT

The conspicuous interindividual differences in metabolism and urinary excretion of testosterone and its metabolites make it challenging to reveal testosterone doping. The variation in testosterone glucuronide excretion is strongly associated with a deletion polymorphism in the uridine diphosphate-glucuronosyltranferase (UGT) 2B17 gene.

OBJECTIVE

The objective of the study was to identify additional biomarkers to detect testosterone abuse and to elucidate alternative pathways for testosterone elimination in individuals devoid of the UGT2B17 enzyme. For this purpose a new ultraperformance liquid chromatographic tandem mass spectrometric method for simultaneous determination of 10 different sulfo- and glucuronide-conjugated steroids was developed.

PARTICIPANTS

Fifty-four healthy male volunteers with two, one, or no allele (ins/ins, ins/del, or del/del) of the UGT2B17 gene participated in the study.

INTERVENTION

Intervention included a single im dose of 500 mg testosterone enanthate.

MAIN OUTCOME MEASURES

Urinary sulfo- and glucuronide-conjugated steroids were measured.

RESULTS

Testosterone sulfate levels decreased in all individuals after the dose. The individual differences in the excretion of all sulfated metabolites were large. Thus, these metabolites will not serve as appropriate biomarkers for testosterone abuse. However, androsterone glucuronide excretion increased in all of our study subjects after the testosterone dose. Etiocholanolone sulfate was excreted at significantly higher levels in UGT2B17 del/del individuals.

CONCLUSION

We propose that the androsterone glucuronide to epitestosterone glucuronide ratio may serve as a complementary biomarker to reveal testosterone abuse.

A high-throughput multicomponent screening method for diuretics, masking agents, central nervous system (CNS) stimulants and opiates in human urine by UPLC-MS/MS

A simple and rapid multicomponent screening method of 130 substances for direct injections of urine samples has been developed. The fully automated method based on ultra-performance liquid chromatography (UPLC) and tandem mass spectrometry (MS/MS) is used for three different classes of doping agents: diuretics, central nervous system stimulants (CNS stimulants) and opiates. The samples are diluted with buffer containing internal standards (IS) by a pipetting robot system into 96-well plates. Samples are injected on a reversed phase sub 2-microm particle column connected to a fast polarity switching and rapid scanning tandem mass spectrometer with an electrospray interface. The software used to evaluate the results produced reports containing a small-sized window for each component and a data table list with flags to indicate any adverse analytical findings in the sample. The report can also be processed automatically using an application software, which interpret the data and indicate if there is a suspicious sample. One 96-well plate can be analyzed within 16 h.