Pharmaceutical compositions and methods for protecting against atrophy of pancreatic islets in a mammal with metabolic syndrome, prediabetes or diabetes are disclosed. The method comprises administering to the mammal a pharmaceutical composition comprising a compound having a chemical structure of formula (I) in an effective amount and a pharmaceutically acceptable carrier:whereinR is H or COCH2COOHm=3 or 4n=0 or 1o=2 andp=1 or 2.
