PhD Scientific Days 2026

Poster Session 3.N - Neurosciences

Coordinated Changes in Behaviour and Gene Expression Following Short-term Social Isolation in the Rat MPOA

Name of the presenter

Hajdu, Tamara

Institute/workplace of the presenter

Semmelweis University Department of Anatomy, Histology and Embryology

Authors

Tamara Hajdu¹, Tamás Láng¹, Fanni Dóra², Botond Drahos¹, Árpád Dobolyi¹
1: Laboratory of Neuromorphology, Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest 1094, Hungary
2: Human Brain Tissue Bank, Semmelweis University, Budapest 1094, Hungary

Text of the abstract

Social isolation affects behaviour and brain function. Short-term isolation may enhance social behaviour as a homeostatic response, whereas prolonged isolation is associated with maladaptive effects. The underlying molecular changes in hypothalamic regions remain poorly understood. The medial preoptic area (MPOA) is a key regulator of social motivation.
We aimed to examine how one week of social isolation influences social behaviour and transcriptomic changes in the MPOA of male rats.
Rats were housed either in groups or in isolation for one week. Social behaviour was assessed using direct interaction, sociability, and social novelty tests, evaluated both manually and with AI-based tracking. Gene expression was analysed by RNA sequencing (n=12 per group), followed by functional enrichment, network analysis, and qRT-PCR validation.
Isolated rats showed increased social investigation and a stronger preference for familiar conspecifics, but reduced interaction with novel animals and a lower social novelty index, indicating impaired social flexibility. AI-based analysis strongly correlated with manual scoring. RNA sequencing revealed widespread transcriptional downregulation (263 downregulated vs. 27 upregulated genes; |log2FC|>0.5, adjusted p<0.05). Network-level analyses indicated that these transcriptional changes form coordinated regulatory patterns. qRT-PCR validation confirmed the RNA-seq findings (r=0.8472, p<0.0001). Downregulated genes were mainly associated with receptor signaling and neuromodulatory processes (Gpr63, Gpr87, Gpr171, Ptger3, Gpha, Cck, Gabrd, F2rl2), as well as synaptic organization (Ntng1, Cpne9) and cholinergic function (Chrna3). In contrast, Pcp4l was upregulated, potentially reflecting altered calcium-dependent excitability.
Short-term social isolation increases social investigation but reduces novelty preference, accompanied by widespread changes in MPOA gene expression affecting neuromodulatory and synaptic pathways.