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Research Compound Comparison Summary

Primary pathway MC4R→cAMP/CREB→BDNF→TrkB-PI3K-Akt Ctr1→Nrf2→ARE→HO-1/NQO1/GCL; Keap1 oxidation Onset of neuroprotection Delayed: 12–24h for full BDNF-TrkB effect Biphasic: immediate chelation (0–30 min) + Nrf2 (4–8h) Primary injury target Trophic deficit; apop

This source-based comparison does not add ratings or recommend a winner.

  • Primary pathway
  • MC4R→cAMP/CREB→BDNF→TrkB-PI3K-Akt
  • Ctr1→Nrf2→ARE→HO-1/NQO1/GCL; Keap1 oxidation
  • Onset of neuroprotection
  • Delayed: 12–24h for full BDNF-TrkB effect
  • Biphasic: immediate chelation (0–30 min) + Nrf2 (4–8h)
  • Primary injury target
  • Trophic deficit; apoptosis; axonal die-back
  • Oxidative stress; lipid peroxidation; Fenton radicals
  • Secondary effects
  • Neuroplasticity; cognition; CREB-driven gene expression
  • Anti-inflammation via NF-κB; ECM remodelling; collagen
  • MCAO/R infarct reduction
  • −38–44%
  • −42–48%
  • Combined MCAO/R infarct reduction
  • −62–68% (additive, independent pathways confirmed)
  • Key blocker
  • K252a (TrkB); SHU9119 (MC4R)
  • ML385 (Nrf2); tetrathiomolybdate (Cu²⁺ chelation)
  • Best acute injury use
  • Post-ischaemic trophic support; TBI secondary neuroprotection
  • Acute oxidative burst suppression; oedema; BBB
  • Best chronic disease use
  • Neurodegeneration (BDNF deficit); cognitive decline; cholinergic loss
  • Oxidative neurodegeneration; α-syn oligomer biology; lipid peroxidation
  • Combination rationale
  • Orthogonal mechanisms → additive protection; sequential timing optimal (GHK-Cu acute, Semax 6–24h onward)
  • 🔗 Related Reading: For Semax’s full BDNF and cognitive biology profile, see our Semax UK Research Guide.