Functional Role of PPARs in Ruminants: Potential Targets for Fine-Tuning Metabolism during Growth and Lactation

Table 1

Activation of PPAR isotypes in ruminants by main long-chain fatty acids or glucose.

LCFA/glucose	Effect on PPAR isotype^@			Method^#	References
	PPAR𝛼	PPAR𝛾	PPAR𝛽/𝛿
16:0	+++	+++	n/a	Indirect	[26, 28, 61]
18:0	+++	+++	n/a	Indirect	[26, 28]
c9-18:1	++	+	n/a	Indirect/Luciferase	[26, 28, 62]
t10-18:1	n/a^&	+	n/a	Indirect	[26]
18:2	+	n/a	n/a	Indirect	[26, 28]
c9,t11-18:2	+	n/a	n/a	Indirect	[26, 28]
t10,c12-18:2	+	±	n/a	Indirect	[26, 28]
CLAmix^$	+	n/a	n/a	Indirect	[36, 77]
20:0	++	n/a	n/a	Indirect	[26, 28]
20:4n-6	++	n/a	++*	Indirect/Luciferase	[68, 77]
20:5n-3	++	++	n/a	Indirect	[26, 28]
22:6n-3	+	n/a	n/a	Indirect	[26, 28]
Glucose	No	n/a	++	Luciferase	[68]

@+++: strong agonist; ++: agonist; +: weak agonist; ±: mixture between agonist and antagonist.
*The 12-HETE, a metabolite of the 20:4n-6 is the actual agonist.
^#Indirect: the effect on PPAR isotype target genes was uncovered by the use of specific PPAR synthetic agonists; luciferase: the use of the PPRE-luciferase construct to test activation of PPAR by agonists.
^$A mixture (ca. 50% each) of the t10,c12- and c9,t11-conjugated 18:2
^&Not available.