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Carbohydrates constitute one of the key classes of biomacromolecules, yet vibrational spectroscopic studies involving carbohydrates remain scarce as spectra are highly congested and lack significant marker vibrations. Recently, we introduced and characterized a thiocyanate-labeled glucose [Gasse et al., J. Chem. Phys. 158, 145101 (2023)] demonstrating 2D-IR spectroscopy of carbohydrates using vibrational probes. Here, we build on that work and test azide groups as alternative for studies of carbohydrates to expand the available set of local probes. Many common carbohydrates with different azide labeling positions, such as galactose, glucose, or lactose, are readily available due to their application in click chemistry and hence do not require additional complex synthesis strategies. In this work, we have characterized azide-labeled glucose,, galactose, acetylglucosamine and lactose in water using IR and 2D-IR spectroscopy to test their potential for future applications in studies of carbohydrate–protein interactions. Our findings indicate that their absorption profiles and vibrational dynamics are primarily determined by the labeling position on the ring. However, we also observe additional variations between samples with the same labeling position. Furthermore, we demonstrate that their usage remains feasible at biologically relevant concentrations, highlighting their potential to probe more complex biological processes, i.e., enzymatic catalysis. [ABSTRACT FROM AUTHOR]

This study aimed to determine energy availability (EA) and within-day energy balance (WDEB) in female soccer players during preseason and also explored eating disorder risk and athlete food choice. We hypothesized commonly used indicators of low energy availability (LEA) risk would correlate with measured EA and WDEB variables, and that food choice determinants would differ according to EA. Eleven National Premier League female soccer players participated in this observational cross-sectional study over 3 weeks. Assessment of resting metabolic rate and physique traits, including bone mineral density, was conducted during Weeks 1 or 3. During Week 2, dietary intake, energy expenditure, and continuous monitor-derived glucose were measured for 5 days. EA was calculated daily and WDEB calculated hourly with deficits/surpluses carried continuously. Questionnaires were administered throughout the 3 weeks, including the Athlete Food Choice Questionnaire, the Eating Disorders Screen for Athletes, and the Low Energy Availability in Females Questionnaire. Resting metabolic rate ratio, bone mineral density, Low Energy Availability in Females Questionnaire, and Eating Disorders Screen for Athletes scores were used as indicators of LEA risk. EA averaged 30.7 ± 7.5 kcals·kg fat-free mass−1·day−1. Approximately one-third (36%) of athletes were at risk of an eating disorder, while approximately half (45%) were identified at risk of the female athlete triad via Low Energy Availability in Females Questionnaire, compared with approximately one-third (36%) of athletes identified with EA < 30 kcal·kg fat-free mass−1·day−1. No athlete achieved EA >45 kcal·kg fat-free mass−1·day−1, and no indicator of LEA risk was associated with calculated EA or WDEB. However, overnight glycemic variability was positively correlated with measured EA (r =.722, p =.012). [ABSTRACT FROM AUTHOR]

The work establishes a requirement for glucose-dependent coordination between energy production and redox homeostasis, which is fundamental for the survival of cancer cells that accumulate Cu and contributes to tumor growth.

Sturgeon are threatened by anthropogenic changes to river systems, including entrainment or impingement at water diversions (i.e. the unwanted passage of fish through a water intake or physical contact with a barrier screen, likely caused by high intake velocities). Though there are no universally accepted protocols to determine water diversion risk, previous studies on sturgeon suggest that laboratory evaluations of swimming performance are an effective way to describe susceptibility to entrainment or impingement. The swimming performance of juvenile Green Sturgeon (~5 cm fork length), Acipenser medirostris, was quantified for fish acclimated to 13 and 18°C for 2 weeks using fixed water velocity endurance tests. Water velocities ranged from 25 to 55 cm s-1, and time-to-fatigue was measured at 5 cm s-1 increments. Green Sturgeon were quicker to exhaust at the lower acclimation temperature (13°C) compared to fish acclimated to 18°C, for example at 40 cm s-1 13°C acclimated fish impinged ~7.7 times faster than 18°C acclimated fish and ~41.3 times quicker at water velocities of 45 cm s-1. Whole-body cortisol grouped by time-to-fatigue (i.e. sustained swimming: time-to-fatigue >200 min, prolonged swimming: time-to-fatigue between 5 and 200 min, rapid swimming: time-to-fatigue

Polybrominated diphenyl ethers (PBDEs) are endocrine-disrupting persistent organic pollutants (POPs) used as flame retardants in a wide range of commercial applications. We have previously reported neurobehavioral and metabolic reprogramming produced by developmental PBDEs. PBDEs perturb the microbiome, an influencer of life-long health, while probiotic supplementation with Limosilactobacillus reuteri (LR) can avert neurobehavioral and endocrine disruption. We, therefore, tested the hypothesis that perinatal maternal LR supplementation would protect gut microbiome richness and diversity, developmental milestones, adult neurobehavior and metabolic homeostasis in PBDE-exposed offspring. C57BL/6N dams were orally exposed to a commercial penta-mixture of PBDEs, DE-71, at 0.1 mg/kg/day, or corn oil vehicle (VEH/CON) during gestation and lactation. Mice offspring received DE-71 or VEH/CON with or without co-administration of LR (ATCC-PTA-6475) indirectly via their mother from gestational day (GD) 0 until postnatal day (P)21 (Cohort 1), or continued to receive LR directly from P22 through adulthood (Cohort 2). Results of fecal 16S rRNA sequencing indicated age- and sex-dependent effects of DE-71 on gut microbial communities. Maternal LR treatment protected against DE-71-induced reduction in α-diversity in P22 females and against β-diversity alterations in P30 males. In females, DE-71 changed the relative abundance of specific bacterial taxa, such as Tenericutes and Cyanobacteria (elevated) and Deferribacterota (reduced). In males, several Firmicutes taxa were elevated, while Proteobacteria, Chlamydiae, and several Bacteroidota taxa were reduced. The number of disrupted taxa normalized by maternal LR supplementation was as follows: 100% in P22 females and 33% in males at P22 and 25% at P30. Maternal LR treatment protected against DE-71-induced delay of postnatal body weight gain in males and ameliorated the abnormal timing of incisor eruption in both sexes. Further, DE-71 produced exaggerated digging in both sexes as well as locomotor hyperactivity in females, effects that were mitigated by maternal LR only in females. Other benefits of LR therapy included normalization of glucose tolerance, insulin-to-glucose ratio and plasma leptin in adult DE-71 females (Cohort 2). This study provides evidence that probiotic supplementation can mitigate POP-induced reprogramming of neurodevelopment, adult neurobehavior, and glucose metabolism in association with modified gut microbial community structure in a sex-dependent manner.

Insulin is an important regulator of whole-body glucose homeostasis. In insulin sensitive tissues such as muscle and adipose, insulin induces the translocation of glucose transporter 4 (GLUT4) to the cell membrane, thereby increasing glucose uptake. However, insulin also signals in tissues that are not generally associated with glucose homeostasis. In the human reproductive endocrine axis, hyperinsulinemia suppresses the secretion of gonadotropins from gonadotrope cells of the anterior pituitary, thereby linking insulin dysregulation to suboptimal reproductive health. In the mouse, gonadotropes express the insulin receptor which has the canonical signaling response of IRS, AKT, and mTOR activation. However, the functional outcomes of insulin action on gonadotropes are unclear. Here, we demonstrate through use of an optimized cell fractionation protocol that insulin stimulation of the LβT2 gonadotropic cell line results in the unexpected translocation of GLUT1 to the plasma membrane. Using our high purity fractionation protocol, we further demonstrate that though Akt signaling in response to insulin is intact, insulin-induced translocation of GLUT1 occurs independently of Akt activation in LβT2 cells.