There is a nice video listed below with a pilot of this plane (in russian but with decent english subtitles), he answers to this question. Wheels indeed deflate

There is a nice video listed below with a pilot of this plane (in russian but with decent english subtitles), he answers to this question. Wheels indeed deflate (not blow) occasionally, this happens when breaks overheat and special thermal plate (at 200C) melts and deflates the wheel gradually, which works as an indicator of overheated break/tyre. Since it happens gradually, there is no danger for the plane itself. The parts for this plane are not that common (they may be shared with An-124 though), so apparently it is easier to carry few wheels than wait for their delivery. The plane caries 10 m.tons of equipment anyway just to load/unload the cargo, so few wheels probably are not that much of a deal.