Biology subjects

Taghipourbibalan, H.

Publications and source records attributed to Taghipourbibalan, H..

4 recordsLinked to original sources

bioRxiv2025

RTFED, an open-source versatile tool for home-cage monitoring of behaviour and fibre photometry recording in mice

BackgroundConventional approaches for studying feeding and reward-driven behaviours require frequent animal handling or relocation of animals to specialized chambers, inducing stress, confounding behavioural outcomes, and limiting continuous (24/7) data collection. In recent years, the Feeding Experimentation Device (FED3) has emerged as a major advance, offering programmable modes of operation, affordable costs, and flexibility for investigating a range of feeding and operant behaviours. However, certain limitations prevent researchers from fully harnessing the FED3s capabilities in a user-friendly manner. New methodHere, we present the Realtime and Remote FED3 (RTFED) developed for continuous and online home-cage monitoring of mice, video recording behaviours and fibre photometry recording. ResultsValidation experiments confirm RTFED integrates well with FED3 to log and transmit behavioural events in real-time. It also incorporates event-triggered video capture through USB cameras, providing additional observational depth. Moreover, RTFED handles TTL signals to the fibre photometry system allowing precise behaviour-neural synchronization. Comparison with existing methodsA key strength of RTFED is its easily customizable architecture, enabling researchers to tailor both software and hardware configurations to meet specific experimental objectives. This flexibility, together with features such as remote data logging and email notifications that allow timely adjustments and animal welfare monitoring based on behavioural observations, substantially reduces animal disturbance and researcher intervention and labour. ConclusionsBy offering a cost-effective and modifiable alternative to proprietary commercial solutions, RTFED broadens accessibility, heightens reproducibility, and deepens investigations into feeding and reward-driven behaviours in home-cage settings, ultimately improving the quality and translational relevance of behavioural research. HighlightsO_LIWe enhanced the utility of FED3 with a graphical user interface called RTFED C_LIO_LIRTFED allows real-time and remote monitoring of mouse feeding and operant behaviour C_LIO_LIIt sends notifications in case of device failures or when flagged behaviours happen C_LIO_LIIt records event-triggered videos of defined behaviour C_LIO_LIRTFED relays sub-millisecond TTL outputs for fiber photometry recording C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=108 SRC="FIGDIR/small/666497v2_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@49674eorg.highwire.dtl.DTLVardef@11d4585org.highwire.dtl.DTLVardef@bf2db1org.highwire.dtl.DTLVardef@150f73d_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

bioRxiv2024

Rapid fluctuations in histamine associated with intake of nutritive and non-nutritive solutions

The neurotransmitter histamine is involved in control of food intake, yet its dynamics during individual feeding episodes remain unexplored. Therefore, we used the novel genetically-encoded histamine sensor, HisLightG, combined with fiber photometry to measure histamine release in two hypothalamic regions critical for the food-suppressive effects of histamine, the paraventricular nucleus of the hypothalamus (PVH), and the ventromedial hypothalamus (VMH). Male mice were tested under different conditions to assess whether hunger, time of day, or the caloric content of the solution they were given affected histamine fluctuations. We found that histamine levels changed rapidly in response to eating. These histamine fluctuations were influenced by experimental conditions, with slightly smaller responses when the test solution was sucralose (both regions) or during the light cycle (PVH only). Notable regional differences were identified, such that in the PVH histamine rebounded to baseline levels, whereas in the VMH histamine remained lower than baseline for at least 10 seconds after licking ceased. In a separate cohort of male and female mice, enhancing histamine tone via administration of a histamine precursor (L-histidine) reduced the number of licks across multiple sucrose concentrations. Together, these findings indicate that histaminergic activity is modulated rapidly during ingestive episodes, and that understanding these release patterns will give insight into histamines role in appetite suppression.

neuroscience↗

bioRxiv2024

A simple action reduces food intake and obesity in mice

Diets that are high in fat cause over-eating and weight gain in multiple species of animals, suggesting that high dietary fat is sufficient to cause obesity. However, high-fat diets are typically provided freely to animals in obesity experiments, so it remains unclear if high-fat diets would still cause obesity if they required more effort to obtain. We hypothesized that unrestricted and easy access is necessary for high-fat diet induced over-eating, and the corollary that requiring mice to perform small amounts of work to obtain high-fat diet would reduce high-fat diet intake and associated weight gain. To test this hypothesis, we developed a novel home-cage based feeding device that either provided high-fat diet freely, or after mice poked their noses into a port one time - a simple action that is easy for them to do. We tested the effect of this intervention for six weeks, with mice receiving all daily calories from high-fat diet, modifying only how they accessed it. Requiring mice to nose-poke to access high-fat diet reduced intake and nearly completely prevented the development of obesity. In follow up experiments, we observed a similar phenomenon in mice responding for low-fat grain-based pellets that do not induce obesity, suggesting a general mechanism whereby animals engage with and consume more food when it is freely available vs. when it requires a simple action to obtain. We conclude that unrestricted access to food promotes overeating, and that a simple action such as a nose-poke can reduce over-eating and weight gain in mice. This may have implications for why over-eating and obesity are common in modern food environments, which are often characterized by easy access to low-cost unhealthy foods.

animal behavior and cognition↗

bioRxiv2024

Intermittent protein restriction elevates food intake and plasma ghrelin in male mice

Low-protein diets affect body weight, body composition, food intake, and food preferences in mice. Furthermore, single periods of protein restriction can have lasting effects on these parameters. We sought to examine the effect of multiple, short, bouts of protein restriction, relative to long-term maintenance on either a control (NR) or protein-restricted (PR) diet. We found that male mice experiencing intermittent protein restriction (IPR) were indistinguishable from NR mice in terms of body weight and composition, but had food intake and plasma ghrelin as high as mice on PR diet, even when they were returned to control diet. This was not found in female mice. The results of this experiment highlight the importance of diet history on food intake and ghrelin levels in male mice, and the difference in how PR diet might affect male and female mice.

physiology↗