Sleep is often misunderstood as a simple “on/off” switch. In reality, it is a sophisticated biological orchestra that regulates everything from our memory to our metabolism. However, when this orchestra plays out of tune, the consequences are severe: recent studies show that individuals with irregular sleep patterns face a 26% higher risk of major cardiovascular events, such as heart attacks.
Despite the complexity of sleep, our current “repair tools” are remarkably blunt. Traditional sleeping pills act like a master switch for the entire city just to turn on one lamp in your living room. These drugs distribute through the whole body, often leading to “hangover” effects, dependency, or a lack of selectivity between the two primary melatonin receptors, MT1 and MT2 (Hill et al., 2026; Pittman & Rihel, 2026).
To solve this, the Medicinal Chemistry and Synthesis (MCS) group at IQAC-CSIC, in collaboration with the Institut Cochin in Paris, is developing a “biological remote control”. Through the field of photopharmacology, scientists have designed a new family of molecules, which act as melatonin analogs equipped with a light-sensitive “hinge” known as azobenzene (Somalo-Barranco et al., 2022, 2023; Zlotos et al., 2014).
In the dark, these molecules remain folded and inactive, unable to “fit” into the brain’s sleep receptors. But with a precise flash of light, the molecule stretches, fitting perfectly into the receptor—the primary controller of our internal clock—and sending a high-speed command to the brain to adjust its state.
The effectiveness of this technology has been validated in zebrafish larvae. These tiny, transparent organisms have sleep-wake cycles very similar to humans. By applying specific wavelengths (such as 380 nm UV light), researchers have demonstrated the ability to instantly trigger behavioral changes, effectively “hacking” the larvae’s activity levels in real-time.
But how do we “illuminate” a drug inside the human body? The answer lies in engineering. Scientists have designed wireless, battery-free devices the size of a grain of rice. Using NFC technology—the same tech used for contactless mobile payments—these implants receive energy from outside the body to power a micro-LED. This allows for the local activation of the drug only “where and when” it is needed, avoiding systemic toxicity and side effects.
This research is moving us from a medicine of “carpet bombing” to one of “surgical illumination.” By advancing these tools, we are not just treating insomnia; we are ensuring that scientific progress provides safer, more effective, and personalized healthcare for everyone. The day your TV remote (or your smartphone) can help fine-tune your heart health and your sleep is closer than you think.
Hill, A. J., Eliopoulos, O., Emtage, J., Oikonomou, G., & Prober, D. A. (2026). Melatonin promotes sleep by suppressing responses to visual stimuli via MT1 receptors. Current Biology. https://doi.org/10.1016/j.cub.2026.03.059
Pittman, T. K., & Rihel, J. (2026). Sleep: Melatonin dims the lights on wakefulness. In Current Biology (Vol. 36, Number 9, pp. R391–R393). Cell Press. https://doi.org/10.1016/j.cub.2026.03.071
Somalo-Barranco, G., Pagano Zottola, A. C., Abdulrahman, A. O., El Zein, R. M., Cannich, A., Muñoz, L., Serra, C., Oishi, A., Marsicano, G., Masri, B., Bellocchio, L., Llebaria, A., & Jockers, R. (2023). Mitochondria-targeted melatonin photorelease supports the presence of melatonin MT1 receptors in mitochondria inhibiting respiration. Cell Chemical Biology, 30(8), 920-932.e7. https://doi.org/10.1016/J.CHEMBIOL.2023.07.009
Somalo-Barranco, G., Serra, C., Lyons, D., Piggins, H. D., Jockers, R., & Llebaria, A. (2022). Design and Validation of the First Family of Photo-Activatable Ligands for Melatonin Receptors. Journal of Medicinal Chemistry, 65(16), 11229–11240. https://doi.org/10.1021/ACS.JMEDCHEM.2C00717/SUPPL_FILE/JM2C00717_SI_002.CSV
Zlotos, D. P., Jockers, R., Cecon, E., Rivara, S., & Witt-Enderby, P. A. (2014). MT1 and MT2 melatonin receptors: ligands, models, oligomers, and therapeutic potential. Journal of Medicinal Chemistry, 57(8), 3161–3185. https://doi.org/10.1021/JM401343C
I am a neuroscientist and toxicologist. I use video tools to explore the behavioral and physiological effects of neuroactive compounds in aquatic models as D. rerio, D. magna, O. latipes or D. labrax.
Passionate about translational science, I am currently involved in the development and validation of photopharmaceuticals as new therapies. In parallel, I coordinate several educational and science outreach programs, with the firm conviction that science should be accessible and inclusive.