Collagen peptides have more human data on knee osteoarthritis symptoms, but even there, results are mixed and effect sizes are often modest
Locasale JW, Grassian AR, Melman T, Lyssiotis CA, Mattaini KR, Bass AJ, Heffron G, Metallo CM, Muranen T, Sharfi H, Sasaki AT, Anastasiou D, Mullarky E, Vokes NI, Sasaki M, Beroukhim R, Stephanopoulos G, Ligon AH, Meyerson M, Richardson AL, Chin L, Wagner G, Asara JM, Brugge JS, Cantley LC, Vander Heiden MG
This makes it one of the most powerful cognitive enhancement compounds available, though it requires medical supervision due to its potency
Although previous studies have largely assigned depressive symptoms to the three monoamine neurotransmitters (dopamine, norepinephrine, or serotonin), we describe a specific peripheral glutamatergic dysfunction (decreased GDH activity in K2 relatively control) that accompanies distinct clinical DE phenotypes with a predominance of parkinsonian neurological symptoms