Related Experiment Video
Updated: May 28, 2026
A Preclinical Controlled Cortical Impact Model for Traumatic Hemorrhage Contusion and Neuroinflammation
Published on: June 10, 2020
Protective effects of melanocortins on short-term changes in a rat model of traumatic brain injury*
Alessandra Bitto1, Francesca Polito, Natasha Irrera
1Department of Clinical and Experimental Medicine and Pharmacology, University of Messina, Messina, Italy.
Objective:
Treatment for traumatic brain injury remains elusive despite compelling evidence from animal models for a variety of therapeutic targets. Melanocortins have established neuroprotective effects against experimental ischemic stroke. We investigated whether melanocortin treatment of traumatic brain injury induces neuroprotection and promotes functional recovery.
Design:
Randomized experiment.
Setting:
Research laboratory at a university hospital.
Subjects:
Male Sprague-Dawley rats (n = 215).
Interventions:
Experimental rat model of diffuse traumatic brain injury, the impact-acceleration model.
Measurement And Main Results:
Brain tissue nitrites, phosphorylation level of extracellular signal-regulated kinases, and c-jun N-terminal kinases; and expression of active caspase-3, tumor necrosis factor-α, BAX, and Bcl-2 as well as serum levels of interleukin-6, high mobility group box-1, interleukin-10, and brain histologic damage were evaluated 24 or 48 hrs after the insult. Sensorimotor orientation and limb use were evaluated at day 7 and learning and memory at days 23-30 after injury. Posttraumatic treatment every 12 hrs with the melanocortin analog [Nle, D-Phe]-α-melanocyte-stimulating hormone (starting 3 or 6 hrs after injury) inhibited traumatic brain injury-induced upregulation of nitric oxide synthesis, phosphorylation level of extracellular signal-regulated kinases, phosphorylation level of c-jun N-terminal kinases, and active caspase-3; reduced expressions/levels of tumor necrosis factor-α, BAX, interleukin-6, and high mobility group box-1; and increased those of Bcl-2 and interleukin-10. These molecular changes were associated with a reduction in brain tissue damage, as highlighted by histopathological findings and improved functional recovery. Pretreatment with the melanocortin MC4 receptor antagonist HS024 abated the positive effects of [Nle, D-Phe]-α-melanocyte-stimulating hormone.
Conclusions:
Our data indicate that melanocortins protect against traumatic brain injury, in a broad time window and through activation of MC4 receptors, by counteracting the main traumatic brain injury-related mechanisms of damage. These findings could have major clinical implications.
