Biology subjects

Baranowski, B.

Publications and source records attributed to Baranowski, B..

3 recordsLinked to original sources

bioRxiv2026

Tirzepatide and Intermittent Cold Exposure Independently Improve Glucose Homeostasis in DIO Mice Housed at Thermoneutrality

Obesity is considered a risk factor for metabolic diseases, including type 2 diabetes, and results from an imbalance between energy intake and energy expenditure. While pharmacological approaches such as tirzepatide, a dual GIP/GLP-1 receptor agonist, effectively reduce food intake and body weight, strategies that enhance energy expenditure (EE) may provide complementary metabolic benefits. Intermittent cold exposure (ICE) is one such approach that enhances EE and improves glucose homeostasis independent of weight loss. However, the combined effects of these interventions remain unexplored. In this study, we investigated the individual and combined effects of tirzepatide and ICE on body composition, energy metabolism, and glucose homeostasis in diet-induced obese (DIO) male and female mice housed at thermoneutrality. After 8 weeks of 45% high-fat diet feeding, mice received tirzepatide (10 nmol/kg) or vehicle and were exposed to ICE (4{degrees}C, 1 h/day, 5 days/week) or remained at thermoneutrality for 3 weeks. Energy expenditure and substrate utilization were assessed using indirect calorimetry at thermoneutrality and during an acute 1 h cold challenge. Tirzepatide reduced body weight, food intake, and adiposity in both sexes, with a greater reduction in lean mass in males. ICE did not affect body weight but improved glucose homeostasis. At thermoneutrality, tirzepatide did not alter total EE but lowered respiratory exchange ratio (RER), indicating a shift toward lipid utilization. In contrast, ICE increased energy expenditure and fat oxidation, with no additive effects observed when combined with tirzepatide. Together, these findings highlight that targeting both energy intake and expenditure represents complementary, but not necessarily additive approaches to improving metabolic health.

physiology↗

bioRxiv2025

Topical application of the cold-mimetic L-menthol decreases wheel running without affecting the beneficial effects of voluntary exercise in mice

Topical application of L-menthol, a pharmacological cold-mimetic and agonist of the cold-sensing receptor TRPM8 (Transient Receptor Potential Cation Channel Subfamily M Member 8), has been shown to stimulate brown adipose tissue (BAT) thermogenesis and reduce weight gain in both obese and lean male mice, without affecting energy intake. While these findings suggest that L-menthol could offer a novel approach to prevent weight gain, its potential to enhance the benefits of exercise on whole-body metabolic health remains unexplored. In this study, we investigated whether daily topical L-menthol application, combined with voluntary wheel running, could enhance exercise-induced improvements in metabolic health in male and female C57BL/6J mice housed at thermoneutrality (29{degrees}C). Our results demonstrated that although L-menthol treatment reduced voluntary wheel running distance there was still a main effect of exercise to reduce fat mass, weight gain and improve glucose tolerance. Indirect calorimetry revealed that L-menthol increased total energy expenditure, potentially explaining improvements in metabolic health despite reductions in voluntary wheel running. These findings suggest that although L-menthol does not enhance the effects of voluntary exercise, it remains a promising strategy for improving metabolic health. Key pointsO_LIL-menthol treatments led to a reduction in voluntary wheel running distance C_LIO_LIDespite the reduced voluntary exercise with L-menthol, wheel running led to significant reductions in fat mass as well as improved glucose tolerance C_LIO_LITreatment with L-menthol increased energy expenditure perhaps providing an explanation for exercise-induced improvements in indices of metabolic health despite reduction in wheel running C_LI

physiology↗

bioRxiv2024

A survey of ADP-ribosyltransferase families in the pathogenic Legionella

BackgroundADP-ribosyltransferases (ARTs) are a superfamily of enzymes implicated in various cellular processes, including pathogenic mechanisms. The Legionella genus, known for causing Legionnaires disease, possesses diverse ART-like effectors. This study explores the proteomes of 41 Legionella species to bioinformatically identify and characterise novel ART-like families, providing insights into their potential roles in pathogenesis and host interactions. MethodsWe conducted a comprehensive bioinformatic survey of 41 Legionella species to identify proteins with significant sequence or structural similarity to known ARTs. Sensitive sequence searches were performed to detect candidate ART-like families. Subsequent validation, including structure prediction of such families, was achieved using artificial intelligence-driven tools, such as AlphaFold. Comparative analyses were performed to assess sequence and structural similarities between the novel ART-like families and known ARTs. ResultsOur analysis identified 63 proteins with convincing similarity to ARTs, organised into 39 ART-like families, including 26 novel families. Key findings include: O_LIDUF2971 family: exhibits sequence similarity to DarT toxins and other DNA-acting ARTs. C_LIO_LIDUF4291 family: the largest newly identified family shows structural and sequence similarity to the diphtheria toxin, suggesting the ability to modify proteins. C_LI Most members of the novel ART families are predicted effectors. Although experimental validation of the predicted ART effector functions is necessary, the novel ART-like families identified present promising targets for understanding Legionella pathogenicity and developing therapeutic strategies. We publish a complete catalogue of our results in the astARTe database: http://bioinfo.sggw.edu.pl/astarte/.

bioinformatics↗