Urinary Excretion Of Metabolites Research Articles

Effect of magnesium deficiency and repeated-restraint stress on excretion of urinary metabolites in rats

Effect of magnesium deficiency and repeated-restraint stress on excretion of urinary metabolites in rats

Gas chromatography-mass spectrometry-based metabolic profiling of androgens, progestins and glucocorticoids in women with polycystic ovary syndrome

Hypothesis/aims of study. Polycystic ovary syndrome (PCOS) is a common disease. Depending on the diagnostic criteria, the disease is seen in 10-20% of women of reproductive age and accounts for 70-80% of all forms of hyperandrogenic syndrome. PCOS is a heterogeneous condition of multifactorial etiology characterized by various clinical, endocrine and metabolic disorders. Therefore, it is important to clarify the specific features of steroid hormone biosynthesis and metabolism and steroidogenesis enzyme activity, as well as to search for new laboratory criteria for early diagnosis and prompt treatment. The aim of this study was to perform metabolic profiling of androgens, progestins and glucocorticoids using gas chromatography-mass spectrometry (GC-MS) in obese and non-obese women with PCOS.
 Study design, materials and methods. We examined 53 women of reproductive age diagnosed with PCOS. The first group included 30 women aged 22 to 29 years with normal body weight. The second group comprised 23 obese patients aged 25 to 33 years with an average body mass index (BMI) of 35.3 0.4 kg/m2. The control group consisted of 25 healthy women aged 26 0.6 years having a normal BMI without clinical and biochemical signs of hyperandrogenism. Immunoassay methods were used to determine the serum levels of luteinizing hormone, follicle-stimulating hormone, free testosterone, 17-hydroxyprogesterone, and sex hormone-binding globulin. A glucose tolerance test was performed to determine glucose and insulin levels before and after load. Urine steroid profiles were studied by GC-MS with the optimization of the sample preparation schedule. Statistical data processing was performed using the STATISTICA for WINDOWS software system (version 10). The main quantitative characteristics of the patients are presented as the median (Me), the 25th percentile and the 75th percentile (Q25Q75). To compare the results obtained in the study groups, the nonparametric Mann-Whitney test was used. The 95% confidence interval was considered statistically significant.
 Results. The article presents a metabolomics analysis of androgens, glucocorticoid hormones and progestins in women with PCOS compared to the control group. It was revealed that non-obese patients with PCOS had increased urinary excretion of androstenedione metabolites, dehydroepiandrosterone and its metabolites, 17-hydroxypregnanolone, pregnantriol, and 5-ene-pregnenes, while obese patients with PCOS had increased that of androsterone and dehydroepiandrosterone metabolites (16-oxo-androstenediol and androstenediol-17) compared to the control group findings. Decreased ratios of cortisol and cortisone tetrahydro metabolite amount to the levels of 11-oxo-pregnanetriol, pregnanetriol and 17-hydroxypregnenolone, when compared to the control group, was obtained in non-obese patients with PCOS, which indicates 21-hydroxylase deficiency. In obese patients with PCOS, four signs of increased 5-reductase activity were obtained, and in PCOS patients with a normal BMI, three signs were obtained, which indicates varying 5-reductase activity in PCOS patients depending on the BMI.
 Conclusion. Quantitative evaluation of androgen and progestin metabolites, as well as 5- and 5-metabolites of androstenedione and glucocorticoids in the study of urine steroid profiles by GC-MS method opens new opportunities for PCOS diagnostics.

Immunotropic effects of so-called slag metabolites (creatinine, urea, uric acid and bilirubin) at rats

Background. The study of the effect of end products of protein and nucleic acid metabolism on the immune system is of interest not only theoretical but also practical in line with the problems of urotoxins and hemodialysis. In previous studies, we found significant links between uricemia and uricosuria, on the one hand, and immune parameters, on the other hand. In this study, the spectrum of nitrogenous metabolites was expanded due to creatinine, urea and bilirubin. Material and methods. Experiment was performed on 60 healthy female Wistar rats. The plasma level and urinary excretion of the nitrogenous metabolites were determined. Immune status was assessed by thymocytogram, splenocytogram, blood leukocytogram and immunocytogram, as well as phagocytosis of blood neutrophils and monocytes. Results. Both negative and positive metabolic-immune correlations were revealed. Calculation of multiple correlation coefficients between individual metabolite parameters and constellations of immune parameters revealed the maximum immunotropic effect of uricosuria (R=0,637). This is followed by excretion of urea (R=0,617) and creatinine (R=0,606), bilirubinemia (R=0,589), creatinineemia (R=0,567), uricemia (R=0,566) and plasma urea level (R=0,500). The canonical correlation between the constellation of nitrogenous metabolites, on the one hand, and the parameters of immunity, on the other hand, was very strong: R=0,921; χ2(154)=282; p<10-6. Conclusion. Nitrogen metabolites exhibit significant immunotropic activity, both suppressor and enhancing.

A non-invasive method to assess the reproductive status of the European badger (Meles meles) from urinary sex-steroid metabolites

Due to their unique reproductive physiology and behaviour, European badgers (Meles meles) are often used as a model to study mammalian reproduction. For reproductive endocrinology, circulating hormone levels are conventionally measured directly from blood samples. However, routine blood sampling is often not practical for wild animals and may induce stress affecting measurement accuracy. Non-invasive alternatives are thus of interest. Circulating hormones are metabolized through different routes, either by the kidneys, to be excreted through urine, or by the liver, to be excreted through faeces. These metabolites can thus be used as a proxy of hormone measurements, provided the species-specific metabolic characteristics are known. Here we tested the suitability of measuring urinary metabolites of circulating plasma sex-steroid hormones (testosterone in males and oestrogen in females) with enzyme immunoassays to assess the reproductive status of the European badger (Meles meles). Biological validation evidenced that urinary testosterone metabolite (UTM) and urinary total oestrogen metabolite (UEM) excretion patterns both corresponded with seasonal badger reproductive patterns on a population level, signaling correlation over a broad time frame. On an individual level, concurrent sampling of urine and plasma showed that male plasma testosterone and UTM levels correlated significantly across seasons, but no short term correlation was evident for total oestrogen and UEM in females. Thus, in badgers, urinary sex-steroid metabolites can be used reliably in the short term to assess male reproductive status at the individual level, but only at the broader population level for females.

Absorption, metabolism, and excretion of orange juice (poly)phenols in humans: The effect of a controlled alcoholic fermentation

The consumption of orange juice provides high concentrations of health-promoting bioactive compounds, the amount of which may increase upon alcoholic fermentation. Although fermentation may offer new prospects for the industry of orange-related products, there is a lack of studies reporting the influence of controlled alcoholic fermentation on the bioavailability of orange juice (poly)phenols in humans. The aim of this study was to evaluate the absorption profile, pharmacokinetic parameters, and urinary excretion of orange juice (poly)phenols in nine volunteers after acute administration of an orange juice and a beverage prepared after controlled alcoholic fermentation of the juice. Plasma and urine samples were analysed through a UHPLC-ESI-MS/MS targeted approach. A total of 24 (poly)phenol metabolites including both flavanone and phenolic acid derivatives were quantified, most of them being recorded only in urine. Phase II conjugates of hesperetin and naringenin were the main metabolites in plasma, while phenolic acids, in particular hydroxybenzoic acids, were the main compounds in urine. (Poly)phenols in both beverages were highly bioavailable (between 46 and 59%) and a notable inter-individual variability was seen. Significant treatment × time interactions were recorded for the sum of flavanones and phenolic acids in plasma, the (poly)phenols in the fermented juice being absorbed faster than after orange juice intake. Nevertheless, despite the food matrix having an impact on the absorption profile of orange juice (poly)phenols, this did not influence the pharmacokinetic parameters and urinary excretion of the (poly)phenol metabolites.

Urinary GC–MS steroid metabotyping in treated children with congenital adrenal hyperplasia.

BackgroundTreatment of children with classic congenital adrenal hyperplasia (CAH) is a difficult balance between hypercortisolism and hyperandrogenism. Biochemical monitoring of treatment is not well defined. ObjectiveCluster analysis of the urinary steroid metabolome obtained by targeted gas chromatography–mass spectrometry (GC–MS) for treatment monitoring of children with CAH. MethodsWe evaluated 24-h urinary steroid metabolome analyses of 109 prepubertal children aged 7.0 ± 1.6 years with classic CAH due to 21-hydroxylase deficiency treated with hydrocortisone and fludrocortisone. 24-h urinary steroid metabolite excretions were transformed into CAH-specific z-scores. Subjects were divided into groups (metabotypes) by k-means clustering algorithm. Urinary steroid metabolome and clinical data of patients of each metabotype were analyzed. ResultsFour unique metabotypes were generated. Metabotype 1 (N = 21 (19%)) revealed adequate metabolic control with low cortisol metabolites (mean: −0.57z) and suppressed androgen and 17α-hydroxyprogesterone (17OHP) metabolites (−0.79z). Metabotype 2 (N = 23 (21%)) showed overtreatment consisting of a constellation of elevated urinary cortisol metabolites (0.62z) and low metabolites of androgens and 17OHP (−0.75z). Metabotype 3 (N = 32 (29%)) demonstrated undertreated patients with low cortisol metabolites (−0.69z) and elevated metabolites of androgens and 17OHP (0.50z). Metabotype 4 (N = 33 (30%)) presented patients with treatment failure reflected by unsuppressed androgen- and 17OHP metabolites (0.71z) despite elevated urinary cortisol metabolites (0.39z). ConclusionMetabotyping, which means grouping metabolically similar individuals, helps to monitor treatment of children with CAH using GC–MS urinary steroid metabolome analysis. This method allows classification in adequately-, over-, or undertreated children as well as identification of patients with treatment failure.

A randomized double-blind trial of 3 aspirin regimens to optimize antiplatelet therapy in essential thrombocythemia

AbstractEssential thrombocythemia (ET) is characterized by abnormal megakaryopoiesis and enhanced thrombotic risk. Once-daily low-dose aspirin is the recommended antithrombotic regimen, but accelerated platelet generation may reduce the duration of platelet cyclooxygenase-1 (COX-1) inhibition. We performed a multicenter double-blind trial to investigate the efficacy of 3 aspirin regimens in optimizing platelet COX-1 inhibition while preserving COX-2–dependent vascular thromboresistance. Patients on chronic once-daily low-dose aspirin (n = 245) were randomized (1:1:1) to receive 100 mg of aspirin 1, 2, or 3 times daily for 2 weeks. Serum thromboxane B2 (sTXB2), a validated biomarker of platelet COX-1 activity, and urinary prostacyclin metabolite (PGIM) excretion were measured at randomization and after 2 weeks, as primary surrogate end points of efficacy and safety, respectively. Urinary TX metabolite (TXM) excretion, gastrointestinal tolerance, and ET-related symptoms were also investigated. Evaluable patients assigned to the twice-daily and thrice-daily regimens showed substantially reduced interindividual variability and lower median (interquartile range) values for sTXB2 (ng/mL) compared with the once-daily arm: 4 (2.1-6.7; n = 79), 2.5 (1.4-5.65, n = 79), and 19.3 (9.7-40; n = 85), respectively. Urinary PGIM was comparable in the 3 arms. Urinary TXM was reduced by 35% in both experimental arms. Patients in the thrice-daily arm reported a higher abdominal discomfort score. In conclusion, the currently recommended aspirin regimen of 75 to 100 once daily for cardiovascular prophylaxis appears to be largely inadequate in reducing platelet activation in the vast majority of patients with ET. The antiplatelet response to low-dose aspirin can be markedly improved by shortening the dosing interval to 12 hours, with no improvement with further reductions (EudraCT 2016-002885-30).

Using hydrocarbons as reagents

The compounds cis-6-(2-acetylvinylthio)purine (cis-AVTP) and trans-6-(2-acetylvinylthio)guanine (trans-AVTG) are glutathione-activated prodrugs of 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG), respectively, that have comparable or lower IC50 values in tumor cells than 6-MP and 6-TG. Previously, we showed that cis-AVTP- and trans-AVTG-treated mice exhibited less bone marrow and intestinal toxicity and excreted a lower fraction of the administered dose in urine than did mice treated with equivalent 6-TG doses. To explain these results, the tissue distribution and levels of metabolites of cis-AVTP, trans-AVTG, and 6-TG were examined at 15, 30, and 45 min after i.p. treatment of mice with equimolar doses of these compounds. After prodrug treatment, the thiopurines, the corresponding thiopurine ribosides and nucleotides, thioxanthine (TX), and thiouric acid (TU) were quantitated in plasma, red blood cells, liver, and intestine. Thiopurine and thiopurine riboside and nucleotide area under the curve between 15 and 45 min [AUC(15–45)] values were generally comparable after cis-AVTP and trans-AVTG treatments but were lower than those after 6-TG treatment. A higher liver/plasma metabolite ratio was evident after trans-AVTG treatment than after cis-AVTP or 6-TG treatments, which exhibited similar liver/plasma ratios. Treatment with cis-AVTP yielded the highest AUC(15–45) for TX and TU in plasma, liver, and intestine. Prodrug treatment did not change the concentration of reduced or oxidized glutathione in tissue homogenates. Collectively, these results show distinct patterns of metabolites depending upon the compound used and suggest that differences in metabolite levels and composition after cis-AVTP, trans-AVTG, and 6-TG treatments may partially explain the different toxicity and urinary metabolite excretion profiles previously observed among cis-AVTP, trans-AVTG, and 6-TG.

Oral Dosing of Dihydromethysticin Ahead of Tobacco Carcinogen NNK Effectively Prevents Lung Tumorigenesis in A/J Mice.

Our early studies demonstrated an impressive chemopreventive efficacy of dihydromethysticin (DHM), unique in kava, against tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumorigenesis in A/J mice in which DHM was supplemented in the diet. The current work was carried out to validate the efficacy, optimize the dosing schedule, and further elucidate the mechanisms using oral bolus dosing of DHM. The results demonstrated a dose-dependent chemopreventive efficacy of DHM (orally administered 1 h before each of the two NNK intraperitoneal injections, 1 week apart) against NNK-induced lung adenoma formation. Temporally, DHM at 0.8 mg per dose (∼32 mg per kg body weight) exhibited 100% lung adenoma inhibition when given 3 and 8 h before each NNK injection and attained >93% inhibition when dosed at either 1 or 16 h before each NNK injection. The simultaneous treatment (0 h) or 40 h pretreatment (-40 h) decreased lung adenoma burden by 49.8% and 52.1%, respectively. However, post-NNK administration of DHM (1-8 h after each NNK injection) was ineffective against lung tumor formation. In short-term experiments for mechanistic exploration, DHM treatment reduced the formation of NNK-induced O6-methylguanine (O6-mG, a carcinogenic DNA adduct in A/J mice) in the target lung tissue and increased the urinary excretion of NNK detoxification metabolites as judged by the ratio of urinary NNAL-O-gluc to free NNAL, generally in synchrony with the tumor prevention efficacy outcomes in the dose scheduling time-course experiment. Overall, these results suggest DHM as a potential chemopreventive agent against lung tumorigenesis in smokers, with O6-mG and NNAL detoxification as possible surrogate biomarkers.

Berry fruits modulate kidney dysfunction and urine metabolome in Dahl salt-sensitive rats

Berries are rich sources of (poly)phenols which have been associated with the prevention of cardiovascular diseases in animal models and in human clinical trials. Recently, a berry enriched diet was reported to decrease blood pressure and attenuate kidney disease progression on Dahl salt-sensitive rats. However, the relationship between kidney function, metabolism and (poly)phenols was not evaluated. We hypothesize that berries promote metabolic alterations concomitantly with an attenuation of the progression of renal disease. For that, kidney and urinary metabolomic changes induced by the berry enriched diet in hypertensive rats (Dahl salt-sensitive) were analyzed using liquid chromatography (UPLC-MS/MS) and 1H NMR techniques. Moreover, physiological and metabolic parameters, and kidney histopathological data were also collected. The severity of the kidney lesions promoted in Dahl rats by a high salt diet was significantly reduced by berries, namely a decrease in sclerotic glomeruli. In addition, was observed a high urinary excretion of metabolites that are indicators of alterations in glycolysis/gluconeogenesis, citrate cycle, and pyruvate metabolism in the salt induced-hypertensive rats, a metabolic profile counteracted by berries consumption. We also provide novel insights that relates (poly)phenols consumption with alterations in cysteine redox pools. Cysteine contribute to the redox signaling that is normally disrupted during kidney disease onset and progression. Our findings provide a vision about the metabolic responses of hypertensive rats to a (poly)phenol enriched diet, which may contribute to the understanding of the beneficial effects of (poly)phenols in salt-induced hypertension.

Prevention of Adrenal Crisis: Cortisol Responses to Major Stress Compared to Stress Dose Hydrocortisone Delivery

ContextPatients with adrenal insufficiency require increased hydrocortisone cover during major stress to avoid a life-threatening adrenal crisis. However, current treatment recommendations are not evidence-based.ObjectiveTo identify the most appropriate mode of hydrocortisone delivery in patients with adrenal insufficiency who are exposed to major stress.Design and ParticipantsCross-sectional study: 122 unstressed healthy subjects and 288 subjects exposed to different stressors (major trauma [N = 83], sepsis [N = 100], and combat stress [N = 105]). Longitudinal study: 22 patients with preserved adrenal function undergoing elective surgery. Pharmacokinetic study: 10 patients with primary adrenal insufficiency undergoing administration of 200 mg hydrocortisone over 24 hours in 4 different delivery modes (continuous intravenous infusion; 6-hourly oral, intramuscular or intravenous bolus administration).Main Outcome MeasureWe measured total serum cortisol and cortisone, free serum cortisol, and urinary glucocorticoid metabolite excretion by mass spectrometry. Linear pharmacokinetic modeling was used to determine the most appropriate mode and dose of hydrocortisone administration in patients with adrenal insufficiency exposed to major stress.ResultsSerum cortisol was increased in all stress conditions, with the highest values observed in surgery and sepsis. Continuous intravenous hydrocortisone was the only administration mode persistently achieving median cortisol concentrations in the range observed during major stress. Linear pharmacokinetic modeling identified continuous intravenous infusion of 200 mg hydrocortisone over 24 hours, preceded by an initial bolus of 50–100 mg hydrocortisone, as best suited for maintaining cortisol concentrations in the required range.ConclusionsContinuous intravenous hydrocortisone infusion should be favored over intermittent bolus administration in the prevention and treatment of adrenal crisis during major stress.

Fermentation of soybean meal improves isoflavone metabolism after soy biscuit consumption by adults

Urinary excretion of isoflavones and their metabolites after the consumption of soybean meal (SBM) and fermented soybean meal (FSBM) biscuits was investigated in humans in a randomized double-blinded crossover clinical trial. Aglycones were the most abundant metabolites in urine in both treatments. After FSBM consumption, total urinary excretion of aglycones and metabolites was 54% higher when compared to SBM biscuits. All metabolites were more rapidly excreted after FSBM biscuit consumption when compared to SBM biscuits. Urinary recovery of isoflavones was higher after FSBM biscuit consumption, reaching 67%. Women excreted higher amounts of colonic metabolites and lower amounts of aglycones than men. The prevalence of O-demethylangolensin-producer, equol-producer and nonproducer metabotypes was 56%, 11% and 36% after SBM consumption and 72%, 11% and 17% after FSBM consumption, respectively. Together, our findings indicate that fermentation improves isoflavone bioavailability and possibly reduces the impact of gut microbiota on the metabolism of isoflavones. © 2020 Society of Chemical Industry.

Endogenous urinary glucocorticoid metabolites and mortality in prednisolone-treated renal transplant recipients.

BackgroundChronic corticosteroid treatment suppresses HPA‐axis activity and might alter activity of 11β hydroxysteroid dehydrogenases (11β‐HSD). We aimed to investigate whether the endogenous glucocorticoid production and 11β‐HSD activities are altered in prednisolone‐treated renal transplant recipients (RTR) compared with healthy controls and whether this has implications for long‐term survival in RTR.MethodsIn a longitudinal cohort of 693 stable RTR and 275 healthy controls, 24‐hour urinary cortisol, cortisone, tetrahydrocorisol (THF), allotetrahydrocortisol (alloTHF), and tetrahydrocortisone (THE) were measured using liquid chromatography tandem‐mass spectrometry. Twenty‐four‐hour urinary excretion of cortisol and metabolites were used as measures of endogenous glucocorticoid production; (THF + alloTHF)/THE and cortisol/cortisone ratios were used as measures of 11β‐HSD activity.ResultsUrinary cortisol and metabolite excretion were significantly lower in RTR compared with healthy controls (P < .001), whereas (THF + alloTHF)/THE and cortisol/cortisone ratios were significantly higher (P < .001 and P = .002). Lower total urinary metabolite excretion and higher urinary (THF + alloTHF)/THE ratios were associated with increased risk of mortality, independent of age, sex, estimated glomerular filtration rate, C‐reactive protein, body surface area, and daily prednisolone dose, respectively.ConclusionsEndogenous glucocorticoid production and 11β‐HSD activities are altered in prednisolone‐treated RTR. Decreased total urinary endogenous glucocorticoid metabolite excretion and increased urinary (THF + alloTHF)/THE ratios are associated with increased risk of mortality.

The Utility of Measuring Urinary Metabolites of Mast Cell Mediators in Systemic Mastocytosis and Mast Cell Activation Syndrome

Mast cells (MCs) leave evidence of their presence and activation. Aside from increased numbers of MCs in tissues, this evidence includes detecting elevated serum levels of tryptase and discovering increased excretion of urinary metabolites of prostaglandin (PG) D2, leukotriene (LT) C4, and/or histamine. The importance of measuring these nontryptase mediator metabolites has largely gone unnoticed. We reviewed the utility of quantitating urinary levels of MC mediator metabolites in systemic mastocytosis (SM) and MC activation disorders and summarized the relative production of these mediators by MCs and other cell types. Quantitation of urinary n-methyl histamine, 2,3-dinor-11βPGF2α, and LTE4 offers a simple, noninvasive avenue to monitor their constitutive release as well as contemporaneous discharge during MC activation as well as supporting a diagnosis of SM. These increases can occur independently of or in addition to raised levels of tryptase. Quantitation of these mediator metabolites potentially offers targets for therapeutic intervention. Synthesis of PGD2, a product nearly exclusively of MCs, can be controlled with aspirin, histamine increase by H1 and H2 receptor blockade, and LTC4 by a 5-LO inhibitor or LT receptor antagonist. Although other sources are reported, the increase in MC numbers in SM supports this cell as the predominant origin of all 3 mediators.

The Role of Protein and Free Amino Acids on Intake, Metabolism, and Gut Microbiome: A Comparison Between Breast-Fed and Formula-Fed Rhesus Monkey Infants.

Background: Compared to breast-fed (BF), formula-fed (FF) infants exhibit more rapid weight gain, a different fecal microbial profile, as well as elevated serum insulin, insulin growth factor 1 (IGF-1), and branched chain amino acids (BCAAs). Since infant formula contains more protein and lower free amino acids than breast milk, it is thought that protein and/or free amino acids may be key factors that explain phenotypic differences between BF and FF infants.Methods: Newborn rhesus monkeys (Macaca mulatta) were either exclusively BF or fed regular formula or reduced protein formula either supplemented or not with a mixture of amino acids. Longitudinal sampling and clinical evaluation were performed from birth to 16 weeks including anthropometric measurements, intake records, collection of blood for hematology, serum biochemistry, hormones, and metabolic profiling, collection of urine for metabolic profiling, and collection of feces for 16s rRNA fecal microbial community profiling.Results: Reducing protein in infant formula profoundly suppressed intake, lowered weight gain and improved the FF-specific metabolic phenotype in the first month of age. This time-dependent change paralleled an improvement in serum insulin. All lower protein FF groups showed reduced protein catabolism with lower levels of blood urea nitrogen (BUN), urea, ammonia, albumin, creatinine, as well as lower excretion of creatinine in urine compared to infants fed regular formula. Levels of fecal microbes (Bifidobacterium and Ruminococcus from the Ruminococcaceae family), that are known to have varying ability to utilize complex carbohydrates, also increased with protein reduction. Adding free amino acids to infant formula did not alter milk intake or fecal microbial composition, but did significantly increase urinary excretion of amino acids and nitrogen-containing metabolites. However, despite the lower protein intake, these infants still exhibited a distinct FF-specific metabolic phenotype characterized by accelerated weight gain, higher levels of insulin and C-peptide as well as elevated amino acids including BCAA, lysine, methionine, threonine and asparagine.Conclusions: Reducing protein and adding free amino acids to infant formula resulted in growth and metabolic performance of infants that were more similar to BF infants, but was insufficient to reverse the FF-specific accelerated growth and insulin-inducing high BCAA phenotype.

Systemic effects of platelet-rich plasma local injection on serum and urinary anabolic metabolites: A prospective randomized study.

Platelet-rich plasma (PRP) is widely utilized in the treatment of sports injuries. However, potential systemic effects after localized PRP injection are unclear at present. In this prospective randomized study, 24 Taiwanese male athletes with tendinopathy were randomized into a PRP group (n = 13) or a saline group (n = 11). The concentrations of serum and urine biomarkers were quantified by enzyme-linked immunosorbent assay assessment as well as gas chromatographic and mass spectrometric analysis, respectively. The results showed no significant differences in serum levels of growth hormone, insulin-like growth factor-1, insulin-like growth factor-binding protein 3, vascular endothelial growth factor, platelet-derived growth factor-BB, or serum substance P(SP) between the two groups before intervention, nor at 1, 2, or 7 days after intervention. However, a significant decrease in the serum SP level 1 and 7 days after PRP injection was observed. Regarding urinary concentrations of metabolites of anabolic androgenic steroids (AAS), no between-group differences before intervention, nor at 1, 2, or 7 days after intervention, were observed. Our study failed to observe significant surge of serum anabolic molecules and urinary excretion of anabolic AAS metabolites after PRP injection.

Metabolism and urinary excretion kinetics of di(2-ethylhexyl) adipate (DEHA) in four human volunteers after a single oral dose

Di(2-ethylhexyl) adipate (DEHA) is used as a substitute for the reprotoxic phthalate plasticizer di(2-ethylhexyl) phthalate (DEHP). This study reports the first quantitative data on human in vivo DEHA metabolism and urinary metabolite excretion with the aim of providing tools for DEHA exposure and risk assessments. After DEHA was administered to four healthy volunteers (107−164 μg/kg body weight (bw)), urine samples were continuously and completely collected for 48 h and analyzed for the specific oxidized monoester metabolites mono-2-ethyl-5-hydroxyhexyl adipate (5OH-MEHA), mono-2-ethyl-5-oxohexyl adipate (5oxo-MEHA), and mono-5-carboxy-2-ethylpentyl adipate (5cx-MEPA), as well as for the non-specific hydrolysis product adipic acid (AA) using stable isotope dilution analysis. AA was confirmed as a major (urinary excretion fraction (FUE): 10–40%), yet non-specific DEHA metabolite. 5cx-MEPA was the major specific DEHA metabolite with an FUE of 0.20% (range: 0.17–0.24%). FUEs for 5OH-MEHA and 5oxo-MEHA were 0.07% (0.03–0.10%) and 0.05% (0.01–0.06%), respectively. The three specific metabolites were excreted with two concentration maxima (tmax1 = 1.5–2.3 h, tmax2 = 3.8–6.4 h). Elimination half-lives (t1/2, calculated after the second tmax) for 5cx-MEPA were calculated between 2.1–3.8 h. The majority (98–100%) of metabolites was excreted within 24 h. The FUE of 5cx-MEPA was applied to demonstrate its applicability for calculating daily intakes based on urinary metabolite levels from three pilot populations. Daily intakes were generally far below the tolerable daily intake (TDI) for DEHA (300 μg/kg bw/day). The highest daily intake (114 μg/kg bw/day) was calculated in individuals after consuming food that had been wrapped in DEHA containing cling film.

Reductions in urinary metabolites of exposure to household air pollution in pregnant, rural Guatemalan women provided liquefied petroleum gas stoves.

BackgroundHousehold air pollution from solid fuels is a leading risk factor for morbidity and mortality worldwide. Pregnant women’s exposure to polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs), two components of solid fuel smoke, is associated with adverse birth outcomes. Even with improved solid fuel stoves, exposure to PAHs and VOCs remains high. Therefore, cleaner cooking fuels need to be prioritized.ObjectiveWe aimed to quantify exposure reduction to PAHs and VOCs among pregnant women in rural Guatemala with a liquefied petroleum gas (LPG) stove intervention.Materials and MethodsUrine from pregnant women (N=50) was collected twice: at < 20 weeks gestation, when women cooked exclusively with wood, and 6–8 weeks after receiving an LPG stove. Metabolites of 4 PAHs and 8 VOCs were analyzed. Concurrent with urine collection, personal 48-hour PM2.5 exposure was measured.ResultsWomen cooking exclusively with wood were exposed to high levels of particulate matter (PM2.5), which was reduced by 57% with the LPG stove. Urinary concentrations of total PAH metabolites (−37%), PMA (benzene metabolite; −49%), and CNEMA (acrylonitrile metabolite; −51%) were reduced. However, recent use of a wood-fired sauna bath led to large increases in excretion of urinary toxicant metabolites (+66–135%).ConclusionsThis is the first study to report PAH and VOC reductions from an LPG stove intervention introduced during pregnancy. However, other sources of air pollution minimized the gains seen from using an LPG stove. Thus, all sources of air pollution must be addressed in concert to reduce exposures to levels that protect health.

Formulation of Broccoli Sprout Powder in Gastro-Resistant Capsules Protects against the Acidic pH of the Stomach In Vitro but Does Not Increase Isothiocyanate Bioavailability In Vivo.

Broccoli sprout powder is a rich source of glucosinolates, which are hydrolysed to isothiocyanates in the presence of the enzyme myrosinase. We showed that in vitro incubation of broccoli sprout powder extract with isolated lymphocytes resulted in the upregulation of transcription factor Nrf2, however, there was no increase in Nrf2 protein levels in lymphocytes isolated 3 h following the ingestion of broccoli sprout powder by healthy volunteers. This highlights the general issue that potential health benefits of food-derived compounds can be compromised by limitations in bioavailability. In vitro experiments showed that the generation of isothiocyanates was reduced when the powder was first exposed to the low pH (1.2) of the stomach and then transferred to the higher pH (6.8) of the intestine. The loss of activity due to pre-exposure to the low stomach pH indicates that formulating the broccoli sprout powder in gastro-resistant formulations should increase that amount of isothiocyanate generated in the intestine for absorption. Gelatin capsules were hand-coated with either Eudragit® L100 or Eudragit® L100-55 and were assessed for their gastro-resistant properties using paracetamol as a model active for dissolution studies. Disintegration and dissolution studies showed that Eudragit® L100-55 coated capsules and DRcapsTM (Capsugel®) failed the United States Pharmacopeia (USP) requirements for gastro-resistant capsules, whereas the Eudragit® L100 coated capsules passed. Five healthy participants were administered 1 g of broccoli sprout powder, ingested either with water or encapsulated in uncoated or gastro-resistant capsules. Urinary excretion of isothiocyanate metabolites over the 24 h period post ingestion was assessed by HPLC. Broccoli sprout powder and uncoated gelatin-encapsulated powder showed comparable excretion of isothiocyanate metabolites (18.4 ± 2.3 and 23.9 ± 2.7 µmol, respectively). The enteric coated capsules provided a significantly longer Tmax than the uncoated gelatin capsules (15.4 ± 2.3 versus 3.7 ± 0.7 h, respectively), indicating protection from disintegration in the stomach, however, the excretion of isothiocyanate metabolites was significantly decreased compared with uncoated capsules (i.e., 8.5 ± 1.1 µmol). The lower in vivo formation or absorption of isothiocyanates observed for the gastro-resistant capsules may be due to participant variation in intestinal pH or transit times, resulting in inappropriate pH conditions or insufficient time for the complete disintegration and dissolution of the capsules.

Efflux transport of nicotine, cotinine and trans-3'-hydroxycotinine glucuronides by human hepatic transporters.

Nicotine is the addiction causing alkaloid in tobacco, and it is used in smoking cessation therapies. Although the metabolic pathways of nicotine are well known and mainly occur in the liver, the transport of nicotine and its metabolites is poorly characterized. The highly hydrophilic nature and urinary excretion of nicotine glucuronide metabolites indicate that hepatic basolateral efflux transporters mediate their excretion. We aimed here to find the transporters responsible for the hepatic excretion of nicotine, cotinine and trans-3'-hydroxycotinine (OH-cotinine) glucuronides. To this end, we tested their transport by multidrug resistance-associated proteins 1 (MRP1, ABCC1) and MRP3-6 (ABCC3-6), which are located on the basolateral membranes of hepatocytes, as well as MRP2 (ABCC2), breast cancer resistance protein (BCRP, ABCG2) and multidrug resistance protein 1 (MDR1, P-gp, ABCB1) that are expressed in the apical membranes of these cells. ATP-dependent transport of these glucuronides was evaluated in inside-out membrane vesicles expressing the transporter of interest. In addition, potential interactions of both the glucuronides and parent compounds with selected transporters were tested by inhibition assays. Considerable ATP-dependent transport was observed only for OH-cotinine glucuronide by MRP3. The kinetics of this transport activity was characterized, resulting in an estimated Km value of 895µmol/L. No significant transport was found for nicotine or cotinine glucuronides by any of the tested transporters at either 5 or 50µmol/L substrate concentration. Furthermore, neithernicotine, cotinine nor OH-cotinine inhibited MRP2-4, BCRP or MDR1. In this study, we directly examined, for the first time, efflux transport of the three hydrophilic nicotine glucuronide metabolites by the major human hepatic efflux transporters. Despite multiple transporters studied here, our results indicate that an unknown transporter may be responsible for thehepatic excretion of nicotine and cotinine glucuronides.