The whole idea of the pentatonic scales is to sound bluesy :D . You can still incorporate bluesy ideas into shred (it won't be blues anymore, but anyway...). You could mix up your blues-based and modal improvisational ideas, like Satch; play on the compound minor/blues scale, following modes and throwing in the odd bluesy lick to mix things up, like Hammett; or just play the pentatonic scales with lots of hammer-ons, pull-offs, and fingertapping, like Zakk Wylde (I advise against the latter approach, though!). Probably the best way is to think about it yourself, and come up with your own approach.