We already know that powerful programming languages can be built with non-ASCII characters in mind -- see APL, for example.
However, we also know that the difficulties of typing these languages without special keyboard support have led to a variety of more English in ASCII language successors such as J/K/L.
The input language has nothing to do with the keyboard. How do you think people type foreign natural languages? This comes up again and again in programming-related online discussions - why is it so hard for people who program software every day to imagine that keyboard input is also mapped by software?
The real reason Iverson used ASCII for J is that in the early 1980s, you had to get an APL character video ROM (code page 907) for your terminal or PC (exactly the same case as for foreign languages). Obviously not a problem at the time for Macs or other computers that use bit-mapped fonts, and has not been a problem for PCs for the past 30 years.
Now, if the natural language has some influence on the semantics of the programming language, it might be useful enough. Doubt it, as most natural languages' grammar is way harder than either English or your average programming language. The only attempt that comes to mind right now would be Lingua::Romana::Perligata[1] and that's just an esolang layer.
Now, for political or philosophical reasons an artificial language might be considered. Like Esperanto or Lojban, but I haven't seen something like this, either (I'm not counting Klingon).
[1]: http://users.monash.edu/~damian/papers/HTML/Perligata.html