Described herein are compositions comprising shortened fibers of poly-N-acetylglucosamine and/or a derivative thereof ("sNAG nanofibers") and the use of such compositions in the treatment of various diseases, in particular, diseases associated with decreased tensile strength of tissue, decreased elasticity of tissue, increased collagen content or abnormal collagen content in tissue, abnormal alignment of collagen in tissue, and/or increased myofibroblast content in tissue.
