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Leclair, L.

Publications and source records attributed to Leclair, L..

2 recordsLinked to original sources

Effects of Polyunsaturated Fatty Acids and Selenoneine on Growth and Lipidomic Profiles in Patient-Derived Prostate Cancer Organoids

Prostate cancer (PCa) is the second most frequent cancer in men and represents a major public health issue worldwide. To complement current therapeutic approaches, our work aims to understand the impact of nutritional interventions on PCa evolution. Recent studies showed that supplementation with omega-3 fatty acids reduces tumour growth in PCa mouse models. Several beneficial effects were observed, particularly on the gut microbiome, suggesting indirect effects on tumours, and whether these fatty acids have a direct molecular impact on the prostate remains elusive. Here, we hypothesized that the prostate directly takes up dietary fatty acids to reprogram metabolism, which could contribute to the beneficial effects on cancer treatment. To test this hypothesis, five series of patient-derived organoids (PDOs), with paired lines originating from normal and tumour samples, were treated with omega-3 and omega-6 fatty acids. While heterogeneity was observed in growth capacities of PDO lines, omega-3 supplementation overall decreased PDO growth, with a stronger decrease in PCa lines. This effect was stronger when co-treated with selenoneine, a nutrient enriched in some marine foods with high omega-3 content. Lipidomic experiments were then performed, revealing that PDOs can take up fatty acids, both omega-3 and omega-6. Furthermore, PDOs could metabolize omega-3 fatty acids into downstream metabolites, even if high inter-patient heterogeneity was observed. Altogether, this study, using PDOs as a working model to study the human prostate, provides a better understanding of the molecular impacts of fatty acid supplementation on prostate and PCa biology for the development of future nutritional interventions.

cancer biology↗

Population Pharmacokinetics and Target Attainment Analysis of Vancomycin after Intermittent Dosing in Adults with Cystic Fibrosis

Vancomycin is the first-line agent to treat pulmonary infections caused by methicillin-resistant Staphylococcus aureus (MRSA) in people with cystic fibrosis (PwCF). However, there is no consensus on vancomycin dosing in this population among health institutions, and there is large variability in dosing regimens across the United States. In this study, we characterized the pharmacokinetics (PK) of vancomycin in PwCF using a population PK approach. The clinical PK data to develop the population PK model was obtained from vancomycin therapeutic monitoring data from PwCF undergoing treatment for infections due to MRSA. The population PK model was then used to perform comprehensive Monte Carlo simulations to evaluate the probability of target attainment (PTA) of 12 different dosing scenarios. The area under the curve to minimum inhibitory concentration ratio (AUC/MIC) [&ge;] 400 mg*h/L was used as a target for PTA analysis. A total of 181 vancomycin plasma concentrations were included in the analysis. A onecompartment model with first-order elimination best described the data. Weight significantly influenced the vancomycin PK (p < 0.05). In the final model, clearance was estimated as 5.52 L/h/70 kg, and the volume of distribution was 31.5 L/70 kg. The PTA analysis showed that at lower MIC levels (MIC = 1), doses greater than and equal to 1000 mg every 8 hours and 1250 mg every 12 hours resulted in >90% PTA. The PTA results from this study may potentially inform the design of vancomycin dosing regimens to treat pulmonary infections due to MRSA in PwCF.

pharmacology and toxicology↗