The Sanz Lab is dedicated to understanding how the brain and mitochondria regulate fundamental aspects of reproduction and metabolism. Our central focus is on kisspeptin (Kiss1) neurons and their role in reproductive physiology. Kiss1 neurons are essential regulators of puberty onset and fertility, and specific subpopulations display remarkable sex-specific differences. We aim to determine how these neurons, particularly those located in the rostral periventricular area of the third ventricle (RP3V), contribute to male reproductive health.In parallel, we investigate how maternal nutrition shapes long-term metabolic health by disrupting hypothalamic circuits that control energy balance. We also study how mitochondrial activity regulates cellular energy production, with a focus on the phosphorylation of the Complex I subunit NDUFS4 at serine 173, a modification considered critical for proper protein maturation and optimal respiratory chain activity. By combining mouse genetics, viral circuit manipulation, molecular profiling, and behavioral analysis, we seek to reveal the cellular and molecular mechanisms that underlie reproduction, metabolism, and mitochondrial biology.