Table 1.

Altered ceramide ratios in insulin resistance, diabetes, and fatty liver disease.

Altered circulating/tissue long and very long chain ceramide ratios associated with insulin resistance and diabetes
Neeland et al. (20)	Increased C16 and C18 ceramides in serum correlated with insulin resistance, total body fat, and visceral fat tissue
	Elevated levels of C24:2, C30:10, and C32:11 ceramides in serum associated with healthier metabolic profiles
Chew et al. (21)	Increased C16, C18, and C20 ceramides in serum correlated positively with body mass index (BMI) and HOMA-IR
Hilvo et al. (22)	Increased C18 ceramide in serum shows the strongest association with incident diabetes. Study identifies C18/16 ratios as an independent marker for risk of incidence of diabetes
Klein et al. (23)	Very long chain ceramides (C20, C20:1, C22.1, C24, C26, and C26:1) are significantly reduced in serum of type 1 diabetic
Bergman et al. (30)	Higher levels of C18 ceramide in skeletal muscle association with insulin resistance and inflammation
Perreault et al. (31)	C18-ceramide levels increased in the skeletal muscle cells isolated from individuals with type 2 diabetes
Increased dihydroceramides/long chain ceramide with fatty liver diseases
Apostolopoulou et al. (25)	Total serum dihydroceramides and hepatic dihydroceramides (16:0, 22:0, and 24:1) increased in NASH Hepatic dihydroceramides (22:0 and 24:1) increased significantly in NASH and strongly associated with whole body insulin-resistance
Wasilewska et al. (26)	Serum saturated ceramides species such as C14, C16, C16:1, C18, and C18:1 significantly higher in children with NAFLD
Rosqvist et al. (27)	Dietary saturated fat markedly induces the fatty liver development, associated with increase serum total ceramides specifically pronounced effect observed in C16 ceramides Dietary polyunsaturated fat prevents fatty liver development associated with reduced serum total ceramides