Lipases are water-soluble enzymes that catalyze the hydrolysis of ester chemical bonds in water-insoluble lipid substrates. Lipases are widely distributed in animals, plants and prokaryotes. The lipase family consists of triglyceride lipases, phospholipases and sphingomyelinases. By the place of action lipases can be divided on 3 sub-classes: extracellular, membrane and intracellular lipases.

Extracellular lipases are represented by Lipase, family member M (LIPM), Lipase, family member K (LIPK) and Lipase, family member N (Lipn). These lipases convert Triacylglycerols extracellular region into Carboxylic acids extracellular region and 1,2-Diacyglycerol extracellular region. Furthermore, the function of these lipases is necessary for keratinocyte differentiation [1].

Membrane lipases are represented by phospholipases: Lipase, member I (LIPI) and Lipase, member H (LIPH). They catalyze conversion of Phosphatidic acid into Free fatty acid and 2-Acyl lysophosphatidic acid, which further participates in phospholipid metabolism [2], [3].

The most abundant intracellular lipases include: Lipoprotein lipase (LPL), Lipase, hepatic (LIPC (HL)), Lipase, endothelial (LIPG) and Lipase, hormone-sensitive (LIPE). All of them catalyze the hydrolysis of triacylglycerol resulting in the formation of 1,2-diacylglycerol. LIPC (HL), LIPG and LIPE also convert 1,2-diacylglycerol into 2-monoacyl glycerol and the latter into glycerol, which participates in triacylglycerol metabolism [4], [5], [6], [7], [8].

In addition, LPL catalyses the conversion of 1,2-diacylglycerol into 1-acyl-glycerol and Free fatty acid and subsequent formation of Free fatty acid and glycerol form 1-acyl-glycerol [4], [9].

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