Fourier Transform Infrared Imaging Supported by Raman Spectroscopy Reveals Biochemical Changes in Adult Rat Brains...

This study employed Fourier Transform Infrared (FTIR) and Raman microspectroscopy to investigate the long-term biochemical effects of prenatal exposure to a ketogenic diet (KD) on the developing rat brain. KD, high in fat and low in carbohydrates, shifts metabolism from glucose to ketone utilization and is widely used to treat drug-resistant epilepsy. Given its potential use in pregnant women, understanding KD impact on offspring neurodevelopment is critically important. By combining the complementary strengths of FTIR and Raman microspectroscopy, this study enabled the detection of subtle biochemical changes within brain tissue of animals fed prenatally with KD. Spectroscopic analyses revealed region- and sex-dependent alterations, primarily involving metabolism of lipids and phosphate-containing compounds─key components of myelin and cellular membranes. Most changes were observed in 60-day-old males prenatally exposed to KD. Creatine- and cholesterol-rich inclusions were detected in hippocampal and cortical regions, possibly reflecting maladaptive outcomes of altered energy metabolism and/or neuroadaptive mechanisms related to metabolic preconditioning. Furthermore, these males exhibited reductions in multiple lipid-associated FTIR parameters, which potentially reflecting disruptions in oligodendrocyte function or myelination dynamics. While 30-day-old females from experimental group showed region-specific lipid decreases and elevated phosphate-related ratios, these changes largely normalized by 60 days, indicating developmental stabilization of metabolic effects after prenatal KD exposure. In contrast to males, females showed no creatine or cholesterol inclusions, likely reflecting sex-specific modulation. Estrogens regulate creatine metabolism, support mitochondrial and antioxidant function, and modulate lipid homeostasis, providing neuroprotection and mitigating metabolic disturbances.