Inhibitory effects of caffeine on gustatory plasticity in the nematode Caenorhabditis elegans

Early-life caffeine exposure induces morphological changes and altered physiology in Caenorhabditiselegans

Caffeine, a widely consumed stimulant, is known for its effects on alertness and fatigue reduction by blockade of adenosine receptors. While it holds therapeutic potential, its diverse impacts pose risks, particularly in early development. This study explores the developmental effects of caffeine exposure using Caenorhabditis elegans (C. elegans) as a model organism. We investigated morphological and behavioral changes induced by caffeine exposure at the L1 stage and assessed their impact at the L4 stage, which roughly corresponds to human infancy and adolescence, respectively. Caffeine-exposed worms displayed increased body length, body bends, and pharyngeal pumping rates compared to control worms. These findings indicate heightened food-seeking behavior and greater food intake, leading to the observed morphological changes. While caffeine did not affect other locomotor behaviors, its stimulatory effect on growth and development highlights its significance. This study provides insights into the potential impact of early-life caffeine exposure on long-term health and development, offering a foundation for future research in vertebrates to uncover its implications on metabolism and other metrics of health.

A Food Supplement with Antioxidative Santa Herba Extract Modulates Energy Metabolism and Contributes to Weight Management

The plant Santa herba (Eriodictyon californicum) contains high flavonoids, thus potentially exerting beneficial effects in context of obesity, often accompanied by inflammation and metabolic imbalance. The study assessed the impact of Santa herba on oxidative stress, energy metabolism, weight reduction, and eating behavior, combining in vitro models with clinical data. Santa herba binding of the adenosine receptor A2A (ADORA2A) was assessed using a radioligand binding assay. A Caenorhabditis elegans model was used to determine mobility boosting effects, and Santa herba oxygen radical absorbance capacity (ORAC) values were determined in comparison to antioxidative plants. Clinical data, that is, body weight and appetite-related parameters, were obtained from overweight and obese women receiving either Santa herba or placebo for 12 weeks. Results showed that Santa herba extract binds to ADORA2A, stimulates C. elegans motility (+7.5%) and locomotion, and yields high antioxidative capacities (ORAC: 819 trolox equivalent). Clinical data, obtained from 24 overweight and 25 obese women (mean: 47.5 years), demonstrated a reduced body weight (P = .042) and body fat (P = .044), and by trend reduced leptin levels (P = .065) in women with obesity after Santa herba consumption compared to placebo. In conclusion, Santa herba extract has energizing and antioxidative properties and may aid in weight management of people with obesity. ClinicalTrials.gov Identifier: NCT03853603.

Kahweol Reduces Food Intake of Caenorhabditis elegans

The coffee diterpene kahweol may contribute to the anti-obesity effects of coffee but its physiological effects have yet to be elucidated. Caenorhabditis elegans is used as an animal model in obesity research because its lipid metabolism is conserved in humans. The goal was to investigate kahweol's effects on lipid metabolism in C. elegans. Kahweol at 120 μM reduced fat accumulation by 17% compared to the control, which was associated with a reduced food intake. Kahweol did not reduce fat in eat-2 mutants, which have a disrupted pharynx contraction rate, suggesting that the fat-lowering effects of kahweol were dependent on food intake. Lipid metabolism-related gene homologues of tubby protein (tub-1), enoyl-CoA hydratase (ech-1.1), adipose triglyceride lipase (atgl-1), insulin/insulin-like growth receptor (daf-2), and forkhead box O transcription factor (daf-16) were also associated with changes in food intake by kahweol. Therefore, kahweol's fat-lowering effects are due to a reduction of food intake in C. elegans.