It's a time-honored bedtime ritual: a warm glass of milk to ease into sleep. While tryptophan often takes credit, scientists have identified casein-tryptic hydrolyzate (CTH)—a blend of milk peptides that reduces stress and enhances sleep. Now, researchers have pinpointed specific peptides in CTH with potential for natural sleep remedies.
Not all adults sleep enough. Prescription sedatives like benzodiazepines and zolpidem treat insomnia but risk side effects and addiction. They often target the brain's GABA receptor to dampen nerve signals. Natural alternatives exist, including peptides from cow's milk casein processed by trypsin into CTH. One standout, α-casozepine (α-CZP), shows promise. Lin Zheng, Mouming Zhao, and colleagues sought even more effective peptides within CTH.
In mouse sleep tests, CTH outperformed α-CZP alone, indicating other active components. Using mass spectrometry on simulated gastric digestion products, the team screened for GABA binding and blood-brain barrier crossing. Top candidate YPVEPF excelled: it boosted mice falling asleep quickly by 25% and extended sleep duration over 400% versus controls. Further CTH peptides and pathways warrant exploration, the researchers note.
