Naveen Nagarajan
Biography
Dr. Naveen received his PhD in Chemistry with a specialization in Biophysics and Neuroscience from the Department of Membrane Biophysics, Max Planck Institute for Biophysical chemistry, Goettingen, Germany, under the guidance of Dr. Christian Rosenmund and Dr. Erwin Neher (1991 Nobel laureate in Physiology or Medicine). He did a postdoctoral fellowship in cellular neuroscience in Mark Bear’s lab at the Picower Institute for Learning and Memory at MIT and systems neuroscience at the Keck Center for Integrative Neuroscience at the University of California, San Francisco with Dr. Michael Merzenich. He joined Dr. Mario Capecchi’s laboratory (2007 Nobel laureate in Physiology or Medicine) at the University of Utah to investigate the role of Hoxb8 gene function in repetitive, anxiety and social behavioral functions in the Hoxb8 mouse model of repetitive behaviors. Dr. Naveen along with Dr. Capecchi discovered a novel brain mechanism in which specialized immune cells called microglia, rather than just neurons, control anxiety and obsessive-compulsive spectrum disorder (OCSD)-like behaviors in mice. Their research challenges the traditional "dogma" that only neurons generate behavior, suggesting instead that microglia act as "accelerators" and "brakes" for repetitive behaviors and anxiety, offering new potential targets for therapeutic intervention. Dr. Naveen was appointed as an Assistant Professor at the Department of Pediatrics/Child Neurology, Pediatrics Research Institute, University of Louisville in 2024.
Research Interests
Dr. Naveen Nagarajan leads the Neuro-Immune Interaction Laboratory (NIIL) to uncover fundamental mechanisms that drive repetitive behaviors, a core feature of neurodevelopmental disorders such as Autism. Human brain health depends on exquisitely balanced neuron–microglia signaling across development and aging. Subtle disruptions in this dialogue may drive neurodevelopmental or neurodegenerative disease. Dr. Naveen and his team members investigate how microbial ecosystems, environmental exposures, and host metabolic states reprogram microglial function during critical windows of brain development. By uniting high-resolution neural circuit imaging, electrophysiological interrogation, multi-omics integration and computational modeling, the group seeks to reveal foundational principles governing brain-microbiome communication and translate these discoveries into transformative strategies for Autism spectrum disorders.
The laboratory focuses on how neuronal activity, microglial surveillance, and microbially derived metabolites converge to shape the neural circuits that regulate behavioral flexibility and motor patterning. By integrating advanced experimental neuroscience with high-resolution genomics, metagenomics, transcriptomics, and metabolomics, the group decodes the molecular and circuit-level signals through which microglia–neuronal interactions influence synaptic remodeling and drive persistent, repetitive behavioral outputs.
The research program delineates mechanistic pathways by which microbiome-derived metabolites and host metabolic states modulate microglial regulation of synaptic pruning within cortico-striatal and associated neural circuits. The lab applies optogenetic perturbations to manipulate circuit activity, employs two-photon in vivo imaging to visualize and quantify microglia-neuron interaction dynamics at the cellular level, and uses miniscope-based calcium imaging to monitor and quantify coordinated neural and microglial ensemble activity during behavior. The lab leverages the unique capabilities of electrophysiological approaches: in vitro brain slice opto-electrophysiology to quantify microglia-mediated modulation of synaptic transmission and neuronal excitability under tightly controlled conditions, and in vivo recordings to quantify microglia-driven alterations in neuronal firing patterns within intact, behaving circuits.
Degrees and Certifications
University of Goettingen