Alzheimer Disease: Kampfl A

Blasko I, Beer R, Bigl M, Apelt J, Franz G, Rudzki D, Ransmayr G, Kampfl A, Schliebs R. · Department of Psychiatry, University Hospital of Innsbruck, Innsbruck, Austria. · J Neural Transm. · Pubmed #15057522 No free full text.

Abstract: Traumatic brain injury (TBI) is a risk factor for the development of Alzheimer's disease (AD). After a traumatic brain injury depositions of amyloid beta (Abeta) in the brain parenchyma were found. In this study we investigated the expression pattern of beta-secretase (BACE-1) in ipsi- or contralateral hippocampus and cortex following controlled cortical TBI in rats. BACE-1 mRNA levels, estimated by real time RT-PCR, were elevated 24 h post injury, and persisting up to 72 h, in the ipsi- and contralateral hippocampus and cerebral cortex as compared to the sham-treated animals (p<0.01). The TBI-induced changes in BACE-1 mRNA are due to enhanced hippocampal and cortical expression of BACE-1 mRNA in neurons and reactive astrocytes as revealed by in situ hybridization. The alterations in hippocampal BACE-1 mRNA levels are accompanied by corresponding increases in BACE-1 protein levels in ipsi- and contralateral hippocampus and ipsilateral cortex as demonstrated by Western blot analysis. In contrast, in the contralateral cortex only a weak increase of traumatically induced BACE-1 protein production was found. The activity of BACE-1 as measured by the formation of the cleavage product of amyloid beta precursor protein, transiently increased up to 48 h after injury, but returned to basal level 7 days post injury. This study demonstrates that the beta-secretase is stimulated following TBI and may suggest a mechanism for the temporal increase of Abeta levels observed in patients with brain trauma.

Franz G, Beer R, Kampfl A, Engelhardt K, Schmutzhard E, Ulmer H, Deisenhammer F. · Department of Neurology, University of Innsbruck, Austria. · Neurology. · Pubmed #12743231 No free full text.

Abstract: OBJECTIVE: To determine whether CSF amyloid beta 1-42 (Abeta-42) and tau have predictive value for prognosis after head injury. METHODS: CSF samples were collected from 29 patients with severe head trauma between 1 and 284 days post-trauma. Abeta-42 and tau levels were measured using sandwich ELISA techniques and compared with CSF levels in patients with cognitive disorders and headache. RESULTS: At all time points, concentrations of Abeta-42 were significantly lower in patients with traumatic brain injury (TBI) than in control groups. A significant correlation existed for Abeta-42 levels and outcome of patients. Below a cutoff of 230 pg/mL, the sensitivity of Abeta-42 to discriminate between good outcome (Glasgow Outcome Score 4 and 5) and poor outcome (Glasgow Outcome Score 1 through 3) was 100% at a specificity of 82%. CSF tau levels were significantly higher in patients with TBI than in any control group. In patients with multiple CSF samples collected at various time points between 1 and 32 days after the trauma, tau levels increased early after TBI, peaked in the second week post-trauma, and slowly decreased thereafter. Independent of outcome, all patients had normal tau levels when CSF was collected more than 43 days post-trauma. CONCLUSIONS: Abeta-42 and tau may play a potential role in the pathophysiology of TBI. Furthermore, the results of this study suggest that Abeta-42 may be a supportive early predictor for recovery after severe head injury.