Blood Concentrations Research Articles

Dried Blood Spots Sampling and Population Pharmacokinetic Modeling for Dosing Optimization of Piperacillin in Chinese Neonates.

Piperacillin is commonly used off-label in neonates for the treatment of bacterial infections. This study aimed to assess a dried blood spots (DBS)-based microsampling strategy for supporting population pharmacokinetics and treatment optimization of piperacillin in Chinese neonates. DBS samples from neonatal patients were collected at predefined intervals. Drug blood concentrations were quantified using a validated ultra-high-performance liquid chromatography-tandem mass spectrometry method. A population pharmacokinetic model was developed using a nonlinear mixed-effects modeling approach. The pharmacokinetic/pharmacodynamics (PK/PD) target was 75% of the time with the unbound drug plasma concentration above the minimum inhibitory concentration (fT>MIC), with a toxicity threshold of unbound drug plasma trough concentration above 64 mg/L. A total of 45 piperacillin samples from 24 neonates were collected. The pharmacokinetics of piperacillin was described using a one-compartment model with postmenstrual age (PMA) as the most significant covariate on clearance. Simulations showed that dosing regimens achieving >90% PK/PD target attainment with <10% risk of possible toxicity were: PMA 33-35 weeks (50 mg/kg q12h), 35-37 weeks (50 mg/kg q8h), and 37-41 weeks (50 mg/kg q6h). In conclusion, Using DBS sampling, we developed a population pharmacokinetic model of piperacillin in Chinese neonates, incorporating PMA to determine optimal dosing regimens.

Intake rates of methylmercury in the Belgian population: Evolution over 40 years

Methylmercury (MeHg) is one of the most toxic compounds, it bioaccumulates and biomagnifies along the food chain and finally damages human's nervous system. Knowing that the main intake route for MeHg in humans is through fish consumption, intake rates were studied in various countries, but not in Belgium. Based on Hg and MeHg measurements in various fishes, mainly from North Sea catches, in combination with the national food consumption surveys, we could calculate daily Hg and MeHg intake rates for the Belgian population in 1975, 1997 and 2014–2021. These values are then compared with daily intake values reported by other countries and with the acceptable daily intake (ADI) values recommended by international organizations. Daily Hg and MeHg intake rates decreased strongly between 1975 and the 2 later periods: while average intake rates are all below the ADI norms, this is not the case for the 95th percentile rates because they exceed or are very close to the ADI values. Since daily MeHg intake rates correlate well with hair and blood concentrations, these were used as a good proxy of MeHg intoxication and were related to health effects observed in children, adolescents, adults and elderly persons living in Belgium via biomonitoring.

B-302 Therapeutic Drug Monitoring (TDM) of Hydroxychloroquine in Whole Blood: Analysis of Over 10,000 Patient Results

Abstract Background Hydroxychloroquine (HCQ), a mainstay of systemic lupus erythematosus (SLE) therapy, improves survival and reduces flares. Therapeutic drug monitoring (TDM) may be useful in 1) identifying and improving adherence issues, 2) titrating daily dose to achieve therapeutic benefits while 3) minimizing retinopathy due to longterm cumulative exposure. Whole blood (WB) is the correct specimen for HCQ TDM because WB HCQ levels are higher than serum or plasma levels, more stable and reflective of the last month of HCQ ingestion, and are better correlated to efficacy and retinopathy risk. Here, we report WB HCQ concentrations in 10,463 clinical patient samples and their distribution. Methods HCQ concentrations in whole blood are measured by liquid chromatography tandem mass spectrometry (LC-MS/MS) and reported in nanograms per milliliters whole blood. Recommended sample collection is ∼ 3 - 6 months into regular stable dosing to reach pharmacokinetic steady state and correlate with clinical efficacy. Results Here, we report the analysis of 10,463 patient samples for whole blood hydroxychloroquine (WB HCQ) concentrations. More than one-third (3752, 35.9%) were within the target range of &amp;gt; 1000 and &amp;lt; 2000 ng/mL. About one-quarter (2568, 24.5%) were within a tighter therapeutic target window, 1000 to 1500 ng/mL. The vast majority (9852, 94.2%,) of all WB HCQ were &amp;lt; 2000 ng/mL with a small percentage &amp;gt;2000 ng/mL (611, 5.8% between 2000 - 9502 ng/mL). About one-third (31.3%) were higher than 1177 ng/mL which corresponds to higher retinopathy risk. Adherence issues were evident in 10.5% (1102) with undetectable (483, 4.6%) and very low (&amp;lt;200 ng/mL) drug (619, 5.9%) (yellow). Depending upon the target threshold, levels &amp;lt; 500 ng/mL or &amp;lt;1000 ng/mL may be considered subtherapeutic as seen in 2498 (23.9%) and 4263 (40.7%) samples, respectively. Conclusions Due to wide pharmacokinetic variability and adherence issues, a given prescribed dose of HCQ does not correspond to WB HCQ, e.g. following 4, 5 or 6 mg/kg/day, levels are known to vary widely from subtherapeutic &amp;lt;500 to &amp;gt;2000 ng/mL. Here, our clinical database reiterates this wide range in WB HCQ levels from undetectable (&amp;lt;25) to 9502 ng/mL in 10,463 patient samples. One-quarter or one-third were within the therapeutic target range of 1000-1500 or 1000-200 ng/mL where &amp;gt;1000 has been associated with better disease control and survival. At the same time, levels less than 1177 avoid higher retinopathy risk. A small percentage of samples, 5.8%, were higher than 2000 ng/mL, suggesting the usefulness in TDM to fine-tune daily dose. In 10%, there was evidence of poor adherence, with very low or no detectable drug, and one quarter to 40% were subtherapeutic (&amp;lt;500 or &amp;lt;1000). The potential benefits of HCQ are many and include reduced flares and improved lupus nephritis, thrombosis risk, and long-term survival. At the same time, prescribed dose does not predict therapeutic levels. TDM-based counseling and dose adjustment may be instrumental in optimizing HCQ benefits while minimizing retinopathy risk. In conclusion, our analysis demonstrates the growing use of whole blood HCQ TDM to facilitate dose titration to safe and most effective target levels.

B-304 Development of free valproic acid estimating equations for adult epileptic patients

Abstract Background Epilepsy is one of the most common neurological disorders, affecting 1.1% adults in United States. Valproic acid (VPA) is an antiepileptic drug with narrow therapeutic window that requires close monitoring of the blood concentration. VPA is highly protein-bound, and the unbound free VPA (fVPA) is the bioactive form responsible for the pharmaceutical effects as well as the toxicity. However, fVPA is not commonly measured in most laboratories but is a test that needs to be sent out to reference laboratories, and the sendout test has a long turnaround time which delays timely patient care. The aim of the study was to develop fVPA estimating equations, to decrease the turnaround time and reduce adverse events, and ultimately improve patients’ outcomes. Methods We retrospectively collected the laboratory results of total valproic acid (tVPA), fVPA and serum albumin along with the patients’ demographic characteristics and other clinical data from 2013 to 2023 in our institution. While the albumin measurement was divided into normal (≥3.5 g/dl) and hypoalbuminemia (&amp;lt;3.5 g/dl) groups, the tVPA and fVPA were categorized into subtherapeutic, therapeutic, and supratherapeutic ranges. Using stepwise model selection, several linear regression equations were developed to predict fVPA concentration for total patients, patients with normal albumin only, and patients with hypoalbuminemia only. The estimated fVPA was then compared to the measured fVPA. The data were analyzed using SAS 9.4, SPSS 28.0 and EP Evaluator EE12. Results A total of 344 concurrent measurements of tVPA/fVPA/serum albumin from 157 patients were obtained, including 180 measurements from patients with normal albumin levels and 164 measurements from patients with hypoalbuminemia. In the patients with normal albumin levels, 32 (17%) were discordant between tVPA and fVPA. More than half of them had therapeutic tVPA but supratherapeutic fVPA. In contrast, 120 (73%) were discordant for the patients with hypoalbuminemia. About half of them had subtherapeutic tVPA but therapeutic fVPA. Several laboratory and clinical parameters including tVPA, albumin, age, sex, congestive heart failure, obesity, and diabetes mellitus were chosen in the final model. In all patients, our equation demonstrated a concordance rate of 66.3% and a bias of 1.46% between the estimated fVPA and the measured fVPA. Likewise, our equation displayed a concordance rate of 70.0% and a bias of -0.03% for patients with normal albumin levels. For patients with hypoalbuminemia, the concordance rate was 69.5% with a bias of 1.97%. In comparison to three previously published equations, our equations obtained increased concordance and decreased bias between estimated fVPA and measured fVPA. Conclusions Our data indicate that free VPA and total VPA do not correlate well according to the therapeutic ranges, especially in patients with hypoalbuminemia. Compared with previously reported equations, our equations showed enhanced concordance and reduced bias between estimated fVPA and measured fVPA, in both patients with normal albumin levels and patients with hypoalbuminemia. Further validation is needed to evaluate the accuracy and generalizability of the equations before clinical application.

B-158 Association between multiple heavy metals exposure and blood lipid levels: evidence from a cross-sectional study of Korean adults

Abstract Background Metals are ubiquitous in our environment and enter human body via various pathways, such as air, soil, food, water, etc. Increasing studies have found that metals are important risk factors in developing dyslipidemia. However, there is no consensus regarding the effects of co-exposure to multiple metals on blood lipid levels. We investigated both the joint and individual effects of this metal mixture exposure on human blood lipid levels. Methods Blood concentrations of four human toxic metals (Pb, Cs, Hg, and Cd) in 2,798 general populations from Korea were simultaneously determined as a measure of exposure. Weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) were used to estimate associations of four blood metals and metals mixture with lipid profiles, including total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C). Results The mean age of the overall study population was 41.2 ± 9.85 years, and 66.9% were men. The prevalence of overweight or obesity, diabetes, and hypertension in the population was 62.5, 6.8, and 13.9%, respectively. In the multivariable linear regression model, the blood Cs was positively associated with TC and LDL-C(p &amp;lt; 0.05, all), and the blood Pb was positively associated with serum TG (p &amp;lt; 0.05, all). Also, the blood Cd was positively associated with serum HDL-C (p &amp;lt; 0.05, all). We did not identify any other obvious interaction between metals on the lipid profiles using a bivariate exposure-response function in BKMR. Conclusions Our finding suggests that combined exposure to this metal mixture may affect human blood lipid levels. Therefore, reducing exposure to heavy metals, such as Cs and Pb, should be a priority for the general population. However, future studies with a larger number of heavy metals are still needed to focus on the detrimental effects of single metals on lipid profiles as well as to identify key components.

Mercury concentrations in blood and back feathers are repeatable, heritable and correlated in a long-lived seabird

Mercury pollution is increasing both in the environment and in various organisms, especially top-predators. If variation in individual mercury concentrations is underpinned by genetic among-individual differences in traits related to mercury uptake, storage or excretion, and results in variation in fitness, populations may have the potential to evolve in response to this development. Few studies, however, have been able to collect sufficient information to investigate the genetic basis of pollution levels. We ran Bayesian quantitative genetic analyses, combining pedigree information obtained from a marine top-predator, the common tern (Sterna hirundo), with total mercury concentrations (THg) measured in 1364 blood and 1560 back feather samples obtained from >600 individual birds across seven years. Blood and back feather THg concentrations differed in repeatability (19 vs. 64 %, respectively), but showed similar levels of heritability (c. 9 %) and evolvability (c. 2 %). Blood and back feather THg concentrations were positively correlated at the phenotypic, but not genetic, level. Although further work is needed to elucidate the uptake, storage or excretion pathways underlying these patterns, our study provides pioneering insights into the architecture of THg concentrations, and suggests that adaptation to environmental pollution may to some extent be possible.

Evaluation of Blood Lactate among Different Player Roles: A Pilot Study on Competitive Young Male Soccer Players.

Soccer match requires anaerobic and aerobic energetic metabolism. The aim of this pilot study was to investigate the changes in blood lactate concentration in young male soccer players in different playing roles at different time points after the soccer match. Following an initial screening of 134 young soccer athletes, 8 male athletes (average age of 15.5 ± 5 SD) were chosen for their characteristics similar to those of competitive athletes. Players were categorized as goalkeeper, central defender, central midfielder, and forward. Blood lactate concentrations were determined using a portable device at different times (10 min, 5 and 16 h) after the soccer match by a maximum effort test on a treadmill. The data were analyzed by one-way analysis of variance ANOVA, followed by Bonferroni's post-hoc test. The following results (mean ± SD) were obtained: VO2max (%) 60.33 ± 3.10; blood lactate (mM) end match (10 min) 2.17 ± 0.78, post-match-early (after 5 h) 2.2 ± 0.42, postmatch-late (16 h) 3.2 ± 0.84. ANOVA analysis indicated that the blood LA concentrations at end-match (10 min) and post-match-early (5 h) were statistically significative lower than those determined at post-match-late (16 h) (p < 0.05). These results suggest that aerobic mechanisms can also use LA as an energy source, contributing to the reduction of its blood concentration. This effect can be due to reduced maximal work during a soccer match and to the LA removal during exercise at reduced intensity. These data can provide indications for planning suitable training strategies for young male soccer players.

Associations between maternal per- and polyfluoroalkyl substances exposure and lipid levels in maternal and cord blood: The Japan environment and Children's study

Despite numerous studies, the associations between per- and polyfluoroalkyl substances (PFAS) exposure and various lipid levels in pregnant women remain ambiguous, especially concerning the association with cord blood lipids.This analysis included 20,960 pregnant women enrolled in the Japan Environment and Children's Study, recruited between 2011 and 2014. Non-fasting plasma samples collected before 22 weeks of gestation were examined for PFAS concentrations. Additionally, non-fasting serum samples collected before, at and after 22 weeks of gestation, at birth, and from cord blood were used to measure total cholesterol (TC) and triglycerides (TG). Linear regression models were applied to quantify the association between each PFAS and various lipid metrics.Among the 28 PFAS analyzed, 7 were quantifiable in more than 80% of participants. Of these, 6 PFAS showed positive associations with TC in maternal blood before 22 weeks of gestation, a trend that remained mostly consistent for maternal blood samples in later stages. However, no associations were found with TC levels in cord blood. Regarding TG, 3 PFAS demonstrated a negative association with TG levels in maternal blood before 22 weeks of gestation, with these relationships generally persisting in later stages, while 4 PFAS were positively associated with TG in cord blood.In summary, this study identified associations between PFAS concentrations in maternal blood and lipid levels in both maternal and cord blood, with differing patterns observed between the two.

Correlations of gray matter volume with peripheral cytokines in Parkinson's disease

IntroductionPeripheral cytokine levels may affect specific brain volumes. Few studies have examined this possible relationship. ObjectiveIn a case–control study, we used magnetic resonance imaging (MRI) voxel-based morphological analysis techniques to examine the relationship between gray matter volume changes and cognitive, motor and emotional dysfunction as well as between gray matter volume changes and peripheral blood cytokine levels. MethodA total of 134 subjects, comprising 66 PD patients and 68 healthy controls, were recruited. Peripheral venous blood was collected to measure the concentrations of 12 cytokines, including IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-17, IFN-α, IFN-γ, and TNF-α. All the subjects also underwent MRI, where 3D-T1-weighted MR images were used for the analysis. In addition, the Montreal Cognitive Assessment (MoCA), Mini-Mental Status Examination (MMSE), Unified Parkinson's disease Rating Scale (UPDRS), Hamilton Anxiety Scale (HAMA), and Hamilton Depression Scale (HAMD) scores were assessed in PD patients. Statistical parameter mapping 12 software was used for the statistical analysis of the images. ResultCompared with control patients, PD patients presented decreased gray matter volume (GMV) in the bilateral frontal lobe, temporal lobe, parietal lobe, occipital lobe, insula, and right cerebellar lobule VIII. Regional GMV in the temporal lobe, parietal lobe, and cerebellum was correlated with MoCA, MMSE, UPDRS, HAMA, and HAMD scores in PDs. In addition, the regional GMV in PDs was correlated with the concentrations of cytokines, including IL-4, IL-6, IFN-γ, and TNF-α. The IL-6 concentration was negatively correlated with the UPDRS-IV score. ConclusionPD patients exhibit gray matter atrophy in a wide range of brain regions, which are symmetrically distributed and mainly concentrated in the frontal and temporal lobes, and these changes may be linked to motor disorders and neuropsychiatric manifestations. Cytokine concentrations in peripheral blood are correlated with regional gray matter volume in PDs, and the IL-6 level affects gray matter volume in the left precentral gyrus and the manifestation of motor complications.

Heat Stress Nephropathy: An Emerging Epidemic of Global Warming.

Climate change has led to global warming since the last century, which has adverse health consequences. Heat stress nephropathy (HSN) is such a disorder that is emerging as an epidemic because of heat exposure, dehydration, and shortage of drinking water. HSN has been suspected to occur in different parts of the world. Many cases of chronic kidney disease of unknown etiology (CKDu) such as Mesoamerican nephropathy and Sri Lankan nephropathy are now being considered as HSN. Influences of agrochemicals (e.g., pesticides), heavy metals (e.g., cadmium, lead, arsenic, and fluoride), and genetic polymorphism were suspected for causation of CKDu in those cases, but results were inconsistent in different studies from different locations. Drinking water with high silica and strontium was also found in a region with high CKDu in South India.1 Malnutrition and infections such as leptospirosis can also cause CKDu. It is not clear whether CKDu in different hot locations studied represents a single disease or a group of different disorders, but the common factors found are heat and related dehydration. However, combined effects may also be possible. Dehydration from heat stress increases toxin exposure of different organs because of higher blood and urine concentration, as chronically dehydrated patients may not excrete toxic substances effectively. Also, the wells and water reservoirs are more concentrated with toxic substances because of hot weather due to evaporation.

Ultrashort Oncologic Whole-Body [18F]FDG Patlak Imaging Using LAFOV PET.

Methods to shorten [18F]FDG Patlak PET imaging procedures ranging from 65-90 to 20-30 min after injection, using a population-averaged input function (PIF) scaled to patient-specific image-derived input function (IDIF) values, were recently evaluated. The aim of the present study was to explore the feasibility of ultrashort 10-min [18F]FDG Patlak imaging at 55-65 min after injection using a PIF combined with direct Patlak reconstructions to provide reliable quantitative accuracy of lung tumor uptake, compared with a full-duration 65-min acquisition using an IDIF. Methods: Patients underwent a 65-min dynamic PET acquisition on a long-axial-field-of-view (LAFOV) Biograph Vision Quadra PET/CT scanner. Subsequently, direct Patlak reconstructions and image-based (with reconstructed dynamic images) Patlak analyses were performed using both the IDIF (time to relative kinetic equilibrium between blood and tissue concentration (t*) = 30 min) and a scaled PIF at 30-60 min after injection. Next, direct Patlak reconstructions were performed on the system console using only the last 10 min of the acquisition, that is, from 55 to 65 min after injection, and a scaled PIF using maximum crystal ring difference settings of both 85 and 322. Tumor lesion and healthy-tissue uptake was quantified and compared between the differently obtained parametric images to assess quantitative accuracy. Results: Good agreement was obtained between direct- and image-based Patlak analyses using the IDIF (t* = 30 min) and scaled PIF at 30-60 min after injection, performed using the different approaches, with no more than 8.8% deviation in tumor influx rate value (Ki ) (mean difference ranging from -0.0022 to 0.0018 mL/[min × g]). When direct Patlak reconstruction was performed on the system console, excellent agreement was found between the use of a scaled PIF at 30-60 min after injection versus 55-65 min after injection, with 2.4% deviation in tumor Ki (median difference, -0.0018 mL/[min × g]; range, -0.0047 to 0.0036 mL/[min × g]). For different maximum crystal ring difference settings using the scan time interval of 55-65 min after injection, only a 0.5% difference (median difference, 0.0000 mL/[min × g]; range, -0.0004 to 0.0013 mL/[min × g]) in tumor Ki was found. Conclusion: Ultrashort whole-body [18F]FDG Patlak imaging is feasible on an LAFOV Biograph Vision Quadra PET/CT system without loss of quantitative accuracy to assess lung tumor uptake compared with a full-duration 65-min acquisition. The ultrashort 10-min direct Patlak reconstruction with PIF allows for its implementation in clinical practice.

Trends in NHANES Biomonitored Exposures in California and the United States following Enactment of California's Proposition 65.

The prevalence of toxic chemicals in US commerce has prompted some states to adopt laws to reduce exposure. One with broad reach is California's Proposition 65 (Prop 65), which established a list of chemicals that cause cancer, developmental harm, or reproductive toxicity. The law is intended to discourage businesses from using these chemicals and to minimize consumer exposure. However, a key question remains unanswered: Has Prop 65 reduced population-level exposure to the listed chemicals? We used national biomonitoring data from the Centers for Disease Control and Prevention (CDC) to evaluate the impact of Prop 65 on population-level exposures. We evaluated changes in blood and urine concentrations of 37 chemicals (including phthalates, phenols, VOCs, metals, PAHs, and PFAS), among US National Health and Nutrition Examination Survey (NHANES) participants in relation to the time of chemicals' Prop 65 listing. Of these, 11 were listed prior to, 11 during, and 4 after the biomonitoring period. The remaining 11 were not listed but were closely related to a Prop 65-listed chemical. Where biomonitoring data were available from before and after the date of Prop 65 listing, we estimated the change in concentrations over time for Californians compared with non-Californians, using a difference-in-differences model. We used quantile regression to estimate changes in exposure over time, as well as differences between Californians and non-Californians at the 25th, 75th, and 95th percentiles. We found that concentrations of biomonitored chemicals generally declined nationwide over time irrespective of their inclusion on the Prop 65 list. Median bisphenol A (BPA) concentrations decreased 15% after BPA's listing on Prop 65, whereas concentrations of the nonlisted but closely related bisphenol S (BPS) increased 20% over this same period, suggesting chemical substitution. Californians generally had lower levels of biomonitored chemicals than the rest of the US population. Our findings suggest that increased scientific and regulatory attention, as well as public awareness of the harms of Prop 65-listed chemicals, prompted changes in product formulations that reduced exposure to those chemicals nationwide. Trends in bisphenols and several phthalates suggest that manufacturers replaced some listed chemicals with closely related but unlisted chemicals, increasing exposure to the substitutes. Our findings have implications for the design of policies to reduce toxic exposures, biomonitoring programs to inform policy interventions, and future research into the regulatory and market forces that affect chemical exposure. https://doi.org/10.1289/EHP13956.

Caveolin 1 ameliorates nonesterified fatty acid-induced oxidative stress via the autophagy regulator Beclin 1 in bovine mammary gland epithelial cells

High blood concentrations of nonesterified fatty acids (NEFA) during ketosis enhance uptake by the mammary gland and impair autophagy while causing oxidative stress. Caveolin 1 (CAV1) is closely related to autophagy and plays a role in regulating oxidative stress. The aim of this study was to explore the potential role of CAV1 on oxidative stress and autophagy during a high NEFA challenge in the immortalized bovine mammary epithelial cell line MAC-T. Mammary gland tissue biopsies and blood samples were collected from healthy (n = 15) and clinically ketotic (n = 15) Holstein cows at 3 to 10 (average = 6) days in milk. Compared with healthy cows, ketotic cows had lower dry matter intake (DMI), daily milk yield, serum glucose and greater serum NEFA and BHBA, accompanied by greater milk fat and lower milk protein. Malondialdehyde (MDA) was greater but activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH) were lower in cows with clinical ketosis. A lower protein abundance of CAV1, Beclin 1, autophagy relative gene 5 (ATG5), and microtubule-associated protein 1 light chain 3 (LC3) as well as greater protein abundance of sequestosome-1 (SQSTM1, also called p62) were detected in mammary tissue of cows with clinical ketosis. In vitro, the MAC-T cells were treated with 0, 0.6 and 1.2 mM NEFA for 12 h or treated with 1.2 mM NEFA for various time points (0, 0.5, 1, 2, 4, 8, 12 and 24 h). Compared with 0 mM NEFA, protein abundance of CAV1, Beclin 1, ATG5 and LC3 was greater in the MAC-T challenged with 0.6 mM NEFA, but lower in the 1.2 mM NEFA group. Protein abundance of p62 was lower with 0.6 mM NEFA, but higher with 1.2 mM NEFA. In response to increasing doses of NEFA, mRNA abundance of CAV1, total antioxidant capacity (T-AOC) and SOD activity decreased while the level of reactive oxygen species (ROS) and content of MDA increased. The protein abundance of CAV1, Beclin 1, ATG5 and LC3 peaked at 0.5 h and 1 h, resulting in both linear and quadratic effects. The protein abundance of p62 decreased, reaching a nadir at 4 h in both a linear and quadratic manner. The silencing of CAV1 in MAC-T cells aggravated the 1.2 mM NEFA-induced decrease in Beclin 1 expression, impaired autophagy, and increase in oxidative stress, whereas the overexpression of CAV1 alleviated these effects. Pretreatment of MAC-T cells with Beclin 1 siRNA (si-Beclin 1) and overexpressing CAV1 followed by challenged with 1.2 mM NEFA reversed the CAV1 induced autophagy, thereby enhancing oxidative stress. Overall, these data suggest that CAV1 protects bovine mammary epithelial cells from NEFA-induced oxidative stress through enhancing the expression of Beclin 1 and activating autophagy.

Molecular correlates of social adversity in breast cancer.

48 Background: Neighborhood disadvantage (ND) is associated with shorter breast cancer (BCa) survival independent of individual, tumor, and treatment factors, suggesting more aggressive tumor biology in women from disadvantaged neighborhoods. This study evaluates how differential DNA methylation (DNAm), gene expression, and biologic pathways are wired with each other to delineate the regulatory landscape of ND on BCa. Methods: We leveraged 55 geocoded ER+/HER2- BCa samples from Hispanic White women enrolled in a prospective genomic-epidemiologic cohort study. Objective ND was evaluated using the Area Deprivation Index (ADI) and subjective ND was evaluated using the patient-reported Neighborhood Social Environment Adversity Survey and the Everyday Expanded Discrimination Survey. We analyzed the association between ND and (1) DNAm, (2) RNA transcription and miRNAs, and (3) blood concentration levels of DNAm co-factors (B12 and folate) from the same patient. To evaluate how the DNAm/expressed pathways are wired with each other to delineate the regulatory landscape of ND in these tumors, we performed correlation analyses among CpGs, genes, and miRNAs in the same topologically associated domain (TAD). We used Spearman correlation as our metric and adjusted the resulting p-values to FDR values. Results: The cohort was divided into low ND (ADI&lt;5; 31%) and a high ND (ADI&gt;=5; 69%). There were no significant differences between groups by age, race/ethnicity, genetic ancestry, BMI, smoking/alcohol, subtype, stage, or OncotypeDX scores. We discovered that high ND exhibits epigenetic deregulation of immune pathways, consistent with our findings of lower circulating B12 in high ND, suggesting activation of immune pathways through reduced systemic availability of methyl donors. RNA-seq identified higher tumor infiltration of immune cells in patients from high ND (e.g., Interferon alpha and gamma responses and inflammatory responses) consistent with aggressive biology. Estrogen response genes were downregulated suggesting that patients from high ND may develop estrogen-resistant tumors. Higher subjective ND scores discovered epigenetic changes on cell adhesion and calcium signaling genes, along with gene expression of E2F targets and cell cycle’s G2M checkpoint, indicative of a more proliferative/stemness signature. TAD analysis discovered significant developmental, immune, and signaling pathways when correlating DNAm with gene expression (e.g., estrogen response and EMT). Conclusions: In this multi-omic matched cohort, we discovered differentially methylated/expressed pathways, consistent with aggressive biology, wired with each other to identify a novel regulatory landscape of ND on BCa. These findings can inform interventions such as improved access to healthy nutrition (B12) in ND/food deserts or targeted stress-reduction interventions based on our survey findings to ultimately reverse aggressive tumor biology and reduce BCa disparities by ND.

Layered double hydroxide nanozyme (LDHzyme)-assisted high-performance electrochemical analysis of organ transplant therapeutic drug concentration

The variability in mycophenolic acid (MPA) exposure levels among organ transplant patients is substantial and directly influences the drug’s therapeutic efficacy. Therefore, precise monitoring of MPA blood concentrations is imperative to devise personalized diagnostic and treatment plans tailored to individual patient profiles. In this study, we developed a screen-printed carbon electrode (SPCE) incorporating Layered Double Hydroxide-based nanozymes (LDHzymes) and multi-walled carbon nanotubes (MWCNT) to achieve high-sensitivity and stable determination of MPA in blood samples. We synthesized three distinct LDHzymes via a straightforward co-precipitation method, selecting CuMn-LDHzyme for its superior electrochemical properties and laccase activity in the context of MPA detection. The sensor’s performance was enhanced by the amalgamation of CuMn-LDHzyme with MWCNT, leveraging the laccase-like activity of CuMn-LDHzyme and the exceptional conductivity of MWCNT to amplify the oxidation current response to MPA. This integration significantly bolstered the sensor’s detection capabilities. The developed electrochemical sensor exhibited remarkable characteristics, including high selectivity, stability, repeatability, and reproducibility. It demonstrated a notable sensitivity with a detection range of 0.5 µM to 200 µM for MPA, and a detection limit of 0.1 µM, effectively detecting MPA in mouse blood samples. These attributes underscore the sensors as promising tool for clinical drug detection, ensuring fast and precise monitoring of MPA levels in organ transplant patients. This innovative approach holds significant promise for advancing personalized medical care and improving therapeutic outcomes.

Species specific kinetics of imidacloprid and carbendazim in mouse and rat and consequences for biomonitoring

This study aimed to develop physiologically based kinetic (PBK) models to predict the blood concentrations of imidacloprid and carbendazim and their primary metabolites 5-hydroxy-imidacloprid and 2-aminobenzimidazole after single or repeated oral exposure in mouse (Mus musculus), and compare this to corresponding kinetic data in rat (Rattus norvegicus). PBK model constants for conversion of imidacloprid and carbendazim and formation and clearance of their selected primary metabolites were quantified by in vitro mouse liver microsomal and S9 incubations. The performance of the newly developed PBK models was evaluated, based on a comparison to available literature data, showing that the models performed well. Predictions made were also compared to results from PBK model simulations for rats reported previously to obtain insight in species dependent differences in kinetics of these pesticides. The results thus obtained revealed substantial species differences in kinetics for these two pesticides between mouse and rat, especially for imidacloprid and to a lesser extent for carbendazim. Repeated dose PBK model simulations revealed that the models can facilitate estimation of external exposure levels under wildlife conditions based on internal blood concentrations of the parent compound. The rate of conversion and liver volume fraction were shown to influence the accuracy of these predictions with lower values providing less variable outcomes. It is concluded that PBK modeling provides a new approach methodology of use for wildlife biomonitoring studies and that results of the present study facilitate benchmarking of the species and compounds for which kinetics enable this with sufficient accuracy.

Changes in drug crystallinity in a commercial tacrolimus amorphous formulation result in variable pharmacokinetics

Tacrolimus capsules contain the drug as the amorphous form. It is well known that drug crystallinity is a risk factor for the performance of amorphous formulations. This study investigated the impact of varying levels of crystalline drug on the pharmacokinetics of tacrolimus following oral dosing of a 5 mg capsule under fasting conditions. Two treatments with percent crystallinity of 20% and 50% were achieved by exposing a marketed generic tacrolimus product to open dish storage conditions of 35 °C and 75% relative humidity (RH) for up to 20 days. Crystallinity was monitored with X-ray powder diffraction. Prograf®, the reference listed drug (RLD), an amorphous generic drug product, and generic drug products containing 20% and 50% crystalline tacrolimus were evaluated. All four treatments were administered to healthy participants in a randomized, single-dose, four-treatment, four-period, four-way crossover study. Blood sampling occurred over 24 h. The amorphous generic tacrolimus product was determined not to be bioequivalent to the RLD. The capsules containing both 20% and 50% crystalline tacrolimus also failed the bioequivalence recommendations when compared to the amorphous generic or to the RLD. Both levels of crystalline tacrolimus resulted in BE failure for both Cmax and AUC parameters. The impact of tacrolimus crystallization was greater for maximum blood concentration (Cmax) values relative to the area-under-the-curve (AUC) values. This study demonstrates that crystalline tacrolimus formed in a marketed generic product and these changes resulted in variable pharmacokinetics which could be of significant clinical concern.

The effects of milling on the chemical forms, bioavailability, and in vivo distribution of Vitamin B1 in rice

Milling not only reduces the content of Vitamin B1 (Vit B1) in rice but may even affect its bioaccessibility, further affecting its activity in vivo. Therefore, this study investigated the changes in Vit B1 content and its chemical forms in rice at different degrees of milling (DOM) before and after cooking, as well as their bioaccessibility in vitro and bioavailability in vivo. In raw unmilled rice, the proportion of bound Vit B1 was slightly lower than that of free Vit B1, and the proportion increased significantly after cooking. DOM< 8% hindered this change of bound Vit B1 after cooking, resulting in a decrease in Vit B1 thermal stability from 90% to 80% and bioaccessibility from 80% to 60%. Fortunately, the content of Vit B1 stabilized in the digestive fluid remained superior to that of the high DOM group. DOM<8% shortened the time for Vit B1 to peak in the blood concentration of mice, whereas the decrease in bioavailability of Vit B1 in blood and liver was insignificant, unlike bioaccessibility. Hence, DOM < 8% can be applied to the rice milling process to maintain nutritional value. Correlation analyses indicated that the bound form of Vit B1 in cooked rice was the main factor affecting its digestion and absorption. These findings provide further support for the development of moderate rice processing.

Machine learning and biological validation identify sphingolipids as potential mediators of paclitaxel-induced neuropathy in cancer patients

Background:Chemotherapy-induced peripheral neuropathy (CIPN) is a serious therapy-limiting side effect of commonly used anticancer drugs. Previous studies suggest that lipids may play a role in CIPN. Therefore, the present study aimed to identify the particular types of lipids that are regulated as a consequence of paclitaxel administration and may be associated with the occurrence of post-therapeutic neuropathy.Methods:High-resolution mass spectrometry lipidomics was applied to quantify d=255 different lipid mediators in the blood of n=31 patients drawn before and after paclitaxel therapy for breast cancer treatment. A variety of supervised statistical and machine-learning methods was applied to identify lipids that were regulated during paclitaxel therapy or differed among patients with and without post-therapeutic neuropathy.Results:Twenty-seven lipids were identified that carried relevant information to train machine learning algorithms to identify, in new cases, whether a blood sample was drawn before or after paclitaxel therapy with a median balanced accuracy of up to 90%. One of the top hits, sphinganine-1-phosphate (SA1P), was found to induce calcium transients in sensory neurons via the transient receptor potential vanilloid 1 (TRPV1) channel and sphingosine-1-phosphate receptors.SA1P also showed different blood concentrations between patients with and without neuropathy.Conclusions:Present findings suggest a role for sphinganine-1-phosphate in paclitaxel-induced biological changes associated with neuropathic side effects. The identified SA1P, through its receptors, may provide a potential drug target for co-therapy with paclitaxel to reduce one of its major and therapy-limiting side effects.Funding:This work was supported by the Deutsche Forschungsgemeinschaft (German Research Foundation, DFG, Grants SFB1039 A09 and Z01) and by the Fraunhofer Foundation Project: Neuropathic Pain as well as the Fraunhofer Cluster of Excellence for Immune-Mediated Diseases (CIMD). This work was also supported by the Leistungszentrum Innovative Therapeutics (TheraNova) funded by the Fraunhofer Society and the Hessian Ministry of Science and Arts. Jörn Lötsch was supported by the Deutsche Forschungsgemeinschaft (DFG LO 612/16-1).

Machine learning and biological validation identify sphingolipids as potential mediators of paclitaxel-induced neuropathy in cancer patients.

Chemotherapy-induced peripheral neuropathy (CIPN) is a serious therapy-limiting side effect of commonly used anticancer drugs. Previous studies suggest that lipids may play a role in CIPN. Therefore, the present study aimed to identify the particular types of lipids that are regulated as a consequence of paclitaxel administration and may be associated with the occurrence of post-therapeutic neuropathy. High-resolution mass spectrometry lipidomics was applied to quantify d=255 different lipid mediators in the blood of n=31 patients drawn before and after paclitaxel therapy for breast cancer treatment. A variety of supervised statistical and machine-learning methods was applied to identify lipids that were regulated during paclitaxel therapy or differed among patients with and without post-therapeutic neuropathy. Twenty-seven lipids were identified that carried relevant information to train machine learning algorithms to identify, in new cases, whether a blood sample was drawn before or after paclitaxel therapy with a median balanced accuracy of up to 90%. One of the top hits, sphinganine-1-phosphate (SA1P), was found to induce calcium transients in sensory neurons via the transient receptor potential vanilloid 1 (TRPV1) channel and sphingosine-1-phosphate receptors.SA1P also showed different blood concentrations between patients with and without neuropathy. Present findings suggest a role for sphinganine-1-phosphate in paclitaxel-induced biological changes associated with neuropathic side effects. The identified SA1P, through its receptors, may provide a potential drug target for co-therapy with paclitaxel to reduce one of its major and therapy-limiting side effects. This work was supported by the Deutsche Forschungsgemeinschaft (German Research Foundation, DFG, Grants SFB1039 A09 and Z01) and by the Fraunhofer Foundation Project: Neuropathic Pain as well as the Fraunhofer Cluster of Excellence for Immune-Mediated Diseases (CIMD). This work was also supported by the Leistungszentrum Innovative Therapeutics (TheraNova) funded by the Fraunhofer Society and the Hessian Ministry of Science and Arts. Jörn Lötsch was supported by the Deutsche Forschungsgemeinschaft (DFG LO 612/16-1).