Background: Short-chain fatty acids (SCFAs) are metabolites produced by the gut microbiota after fiber fermentation. Some SCFAs, such as acetate, propionate, and butyrate, have been recognized as essential for human health, especially for the brain; however, the cellular mechanisms activated by these molecules in food-intake-related organs, such as the olfactory bulb, remain unclear. Objective: This study evaluates the effects of acetic acid (AA) and sodium butyrate on the physiology of Ca²⁺ metabolism in olfactory bulb cells (OBCs). Methods: Primary OBC cultures of the postnatal rat (P7-21) were made, and Ca²⁺ imaging experiments were performed to record the intracellular Ca²⁺ responses (iCaR) elicited by the application of AA and sodium butyrate (100 nM–1 mM). Immunocytochemical analyses were performed to identify GFAP⁺ cells and GPR41 and GPR43 receptors in OBCs. Endpoint RT-PCR analyses were made to identify GPR41 and GPR43 transcripts in OBCs. Results: Fewer than 10% of the OBCs tested responded to the application of AA and sodium butyrate with iCaR. Pharmacological studies (20 µM 2-aminoethyl diphenylborinate (2-APB); 10 nM GLPG0974, 120 nM AR420626) showed that iCaR were independent of inositol triphosphate (IP₃)-signaling pathways and that OBCs expressed both GPR41 and GPR43 receptors. Endpoint RT-PCR studies performed in both olfactory bulbs and primary OBC cultures confirmed the expression of the GPR41 receptor. Conclusions: This study shows that AA and butyrate induce intracellular Ca²⁺ responses activated by GPR41 and GPR43 receptors in a discrete cellular population of the rat olfactory bulb.

Two chiral copper(II) Schiff base complexes (L1Cu and L2Cu) derived from the amino acid alanine and two salicylaldehydes (one of them chlorine substituted) were synthesized and characterized by SCXRD, spectroscopic techniques (FTIR, UV-Vis, EPR), and thermal analysis. SCXRD revealed distorted square-pyramidal geometries, with axial elongation and strong equatorial Cu–N/O bonds indicative of Jahn-Teller distortion. Spectroscopic data confirmed covalent metal-ligand interactions and a dx2−ᵧ2 ground state, consistent with their catalytic activity. In styrene cyclopropanation, both complexes achieved 99.9% yield, but L1Cu exhibited superior stereocontrol (100:0 trans:cis, 66:34 RR:SS) compared to L2Cu (98:2, 60:40), highlighting the electronic influence of the Cl substituent. For C–S coupling, L1Cu outperformed L2Cu (93% vs. 87% yield), with both generating minimal disulfide byproduct (~6.4%). These results demonstrate how subtle ligand modifications tune reactivity and selectivity in distinct transformations, offering insights for designing versatile Cu(II) catalysts.