The present invention relates to novel pyridine alkaloid compounds of formula (I): or a pharmaceutically acceptable derivative thereof as described in the specification, the process for the preparation of the same, and the composition comprising the same. The uses of a pyridine compound for increasing the activity of PPARγ, for the prevention and/or treatment of a disease or disorder related to insulin resistance, and for the prevention and/or treatment of metabolic syndrome or its complication are also provided. The invention also provides extracts of red yeast-fermented products and their uses for prevention and/or treatment of a disease or disorder related to insulin resistance, such as metabolic syndrome.