Hyaluronic acid oligosaccharides having a size selected from sizes of 4 to
60 saccharides, fractions containing the hyaluronic acid oligosaccharides
and having particular physicochemical properties, and drugs containing
the same. The hyaluronic acid oligosaccharides of the present invention
are extremely useful, because they exert superior pharmaceutical effects
as active ingredients of a heat shock protein expression promoter, cell
death inhibitor, cell injury inhibitor and cell and tissue protecting
agent (e.g., organ preservation agent, antiulcer agent, antihepatopathic
agent, IL-10 production promoter or IL-8 production inhibitor) and
exhibit high safety.
