Cell death in the injured brain: roles of metallothioneins.
In traumatic brain injury (TBI), the primary, irreversible damage associated with the moment of impact consists of cells dying from necrosis. This contributes to fuelling a chronic central nervous system (CNS) inflammation with increased formation of proinflammatory cytokines, enzymes and reactive oxygen species (ROS). ROS promote oxidative stress, which leads to neurodegeneration and ultimately results in programmed cell death (secondary injury). Since this delayed, secondary tissue loss occurs days to months following the primary injury it provides a therapeutic window where potential neuroprotective treatment could alleviate ongoing neurodegeneration, cell death and neurological impairment following TBI. Various neuroprotective drug candidates have been described, tested and proven effective in pre-clinical studies, including glutamate receptor antagonists, calcium-channel blockers, and caspase inhibitors. However, most of the scientific efforts have failed in translating the experimental results into clinical trials. Despite intensive research, effective neuroprotective therapies are lacking in the clinic, and TBI continues to be a major cause of morbidity and mortality. This paper provides an overview of the TBI pathophysiology leading to cell death and neurological impairment. We also discuss endogenously expressed neuroprotectants and drug candidates, which at this stage may still hold the potential for treating brain injured patients.
Section of Neuroprotection, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, The Panum Institute, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark. majsan_43@yahoo.se
Mie Ø
MØ
Pedersen
Agnete
A
Larsen
Meredin
M
Stoltenberg
Milena
M
Penkowa
D001930:Brain Injuries / Q000188:drug therapy* / Q000503:physiopathology; D016923:Cell Death; D006801:Humans; D008668:Metallothionein / Q000627:therapeutic use*; D018696:Neuroprotective Agents / Q000627:therapeutic use*
D018696:Neuroprotective Agents; D008668:Metallothionein