Cognitive decline / neurodegen / TBI

In a randomised, double-blind, placebo-controlled trial in moderate Parkinson's disease, weekly exenatide improved off-medication MDS-UPDRS motor scores versus placebo, an effect sustained after a 12-week washout.

Oral semaglutide is being tested in randomised placebo-controlled trials in preclinical/prodromal Alzheimer's disease to determine whether it reduces cortical tau accumulation and neuroinflammation in amyloid-positive adults.

In a clinical study of 110 ischemic stroke patients, adding Semax raised plasma BDNF, accelerated functional recovery, and improved Barthel index and motor outcomes; preclinical work supports its nootropic/neuroprotective activity.

Dihexa is a small-molecule angiotensin IV analog developed to promote synaptogenesis and augment cognition in Alzheimer's and Parkinson's disease models, addressing the loss of synaptic connections underlying neurodegeneration.

In an aged, hypertensive mouse model, the mitochondria-targeted peptide SS-31 (elamipretide) was evaluated as protection against mitochondrial oxidative stress driving cerebral microhemorrhages linked to vascular cognitive impairment.

Humanin, a mitochondria-derived peptide, protects neurons from amyloid-beta toxicity and oxidative stress in Alzheimer's models; brain expression falls with aging, and it is tracked as a mitochondrial-stress biomarker in human studies.

PACAP is among neuropeptides shown to exert neuroprotective effects in Alzheimer's models, reducing amyloid-beta accumulation and neuronal loss; its levels and receptors are altered in Alzheimer's disease.