Botulinum Toxin Type A for the Treatment of Post-traumatic Headache: A Randomized, Placebo-Controlled, Cross-over Study.

INTRODUCTION: Botulinum toxin type A (BoNT/A) is an approved treatment for chronic migraine and has been shown to be effective in reducing number, days, and severity of headache in other headache disorders. Whether botulinum toxin is a safe and effective treatment specifically for post-traumatic headache (PTH), however, is unknown. This study sought to determine whether treatment with BoNT/A improved symptoms of PTH in military veterans. MATERIALS AND METHODS: Forty subjects with PTH were randomized to receive treatment of either BoNT/A or a saline placebo. Sixteen weeks post-treatment or at return to baseline headache severity, subjects were crossed over to receive treatment with the other medication than previously treated with in the first session. Subjects recorded number of headaches, number of headache days, and headache pain severity in daily diaries. Outcome measures included change in the weekly number of headaches, number of headache days per week, and headache pain severity compared to baseline, and the change in number of headaches and number of headaches days at baseline compared to the rating scores averaged across weeks 6-11. RESULTS: The number of headaches per week significantly decreased by 2.24 (43.3%) with BoNT/A treatment (P < .001) and significantly increased by 1.28 (35.1%) with placebo (P = .02) at the end of the 16 weeks and the difference between groups was also significant (P < .001). The number of headache days per week also significantly decreased by 2.24 (44.4%) at the end of 16 weeks with BoNT/A treatment (P < .001), was not significantly changed with placebo, and the difference between the two groups was significant (P < .001). Both the change in number of headaches and number of headache days averaged across weeks 6-11 compared to baseline were significantly decreased in the BoNT/A group (1.6 and 1.4, respectively) compared to a significant increase of 0.3 in number of weekly headaches and a nonsignificant decrease of 0.1 in number of headache days for the placebo group (P = .048 and P = .005, respectively). Headache pain severity was significantly reduced by 0.06 with botulinum toxin treatment (P = .02) and was not significantly increased by 0.04 in the placebo group with a significant difference between groups (P = .006). CONCLUSIONS: Treatment with BoNT/A clinically and significantly improved the frequency and pain severity of PTH compared to placebo in military veterans. Limitations of the study include subject dropout, adherence to documenting variables daily in the dairy, and only one treatment of BoNT/A. Strengths include the cross-over study design, which demonstrated that BoNT/A was effective regardless of treatment order. This dataset is the first prospective study to evaluate BoNT/A as an intervention for symptoms of PTH and provides evidence that larger-scale and multiple treatment studies evaluating BoNT/A for this headache type are warranted.

Antiapoptotic properties of α-crystallin-derived peptide chaperones and characterization of their uptake transporters in human RPE cells.

PURPOSE: The chaperone proteins, α-crystallins, also possess antiapoptotic properties. The purpose of the present study was to investigate whether 19 to 20-mer α-crystallin-derived mini-chaperone peptides (α-crystallin mini-chaperone) are antiapoptotic, and to identify their putative transporters in human fetal RPE (hfRPE) cells. METHODS: Cell death and caspase-3 activation induced by oxidative stress were quantified in early passage hfRPE cells in the presence of 19 to 20-mer αA- or αB-crystallin-derived or scrambled peptides. Cellular uptake of fluorescein-labeled, α-crystallin-derived mini-peptides and recombinant full-length αB-crystallin was determined in confluent hfRPE. The entry mechanism in hfRPE cells for α-crystallin mini-peptides was investigated. The protective role of polycaprolactone (PCL) nanoparticle encapsulated αB-crystallin mini-chaperone peptides from H2O2-induced cell death was studied. RESULTS: Primary hfRPE cells exposed to oxidative stress and either αA- or αB-crystallin mini-chaperones remained viable and showed marked inhibition of both cell death and activation of caspase-3. Uptake of full-length αB-crystallin was minimal while a time-dependent uptake of αB-crystallin-derived peptide was observed. The mini-peptides entered the hfRPE cells via the sodium-coupled oligopeptide transporters 1 and 2 (SOPT1, SOPT2). PCL nanoparticles containing αB-crystallin mini-chaperone were also taken up and protected hfRPE from H2O2-induced cell death at significantly lower concentrations than free αB-crystallin mini-chaperone peptide. CONCLUSIONS: αA- and αB-crystallin mini-chaperones offer protection to hfRPE cells and inhibit caspase-3 activation. The oligopeptide transporters SOPT1 and SOPT2 mediate the uptake of these peptides in RPE cells. Nanodelivery of αB-crystallin-derived mini-chaperone peptide offers an alternative approach for protection of hfRPE cells from oxidant injury.