From Transcriptional Reprogramming to Fat Quality Improvement: Dietary Artemisia ordosica Krasch. Optimizes Fatty...

This experiment investigated the effects of dietary Artemisia ordosica Krasch. (AOK) supplementation on the n3-polyunsaturated fatty acid (n3-PUFA) profile of subcutaneous adipose tissue (SADT) in Arbas cashmere goats and explored the underlying transcriptional mechanisms. Forty healthy, weaned kids (120 ± 10 days of age; similar body weight) were randomly allocated to two groups (n = 20): a control group (CON, basal diet) and an AOK group (AOK, basal diet with 3% of the roughage replaced by AOK). The feeding trial spanned 104 days, consisting of a 14-day adaptation period and 90 days of data acquisition. Compared with the CON group, AOK significantly reduced the content of saturated fatty acids (SFAs) and n6-polyunsaturated fatty acids (n6-PUFAs)/n3-PUFAs (n6/n3). In contrast, the levels of n3-PUFAs in the SADT of cashmere goats increased markedly (p < 0.05). Compared with the CON group, AOK exhibited significantly higher activities of hormone-sensitive lipase (HSL) (p = 0.027), adenylyl cyclase 2 (ADCY2) (p = 0.010), adenylyl cyclase 5 (ADCY5) (p = 0.046), cluster of differentiation 36 (CD36) (p = 0.013), solute carrier family 27 member 4 (SLC27A4) (p = 0.021), and fatty acid binding protein 4 (FABP4) (p = 0.040), along with significantly lower activities of fatty acid synthase (FAS) (p = 0.002), lipoprotein lipase (LPL) (p = 0.048), and stearoyl-coa desaturase (SCD) (p = 0.026) in SADT. Compared with the CON group, the activities of superoxide dismutase (SOD) (p = 0.032), catalase (CAT) (p = 0.010), glutathione peroxidase (GSH-PX) (p = 0.029), and total antioxidant capacity (T-AOC) (p = 0.002) were significantly increased in the AOK group. Transcriptomic profiling revealed that AOK supplementation downregulated mRNA levels of ADCY2, ADCY5, LPL, FAS, SCD, stearoyl-CoA desaturase 1 (SCD1), stearoyl-CoA desaturase 2 (SCD2), glycogen synthase 1 (GYS1), acyl-CoA oxidase 1 (ACOX1), acetyl-CoA carboxylase (ACC), diacylglycerol acyltransferase 1 (DGAT1), fatty acid desaturase 1 (FADS1), solute carrier family 27 member 2 (SLC27A2), erythroblastic leukemia viral oncogene homolog 4 (ERBB4), and carnitine palmitoyltransferase 1B (CPT1B) (p < 0.05). It also markedly induced acyl-CoA synthetase long-chain family member 4 (ACSL4) (p < 0.01) in SADT. Genes significantly enriched in the adenosine-monophosphate-activated protein kinase (AMPK) signaling pathway included LPL, SCD1, CPT1B, and GYS1 (p = 0.010). Genes significantly enriched in the phosphatidylinositol 3-kinase-akt (PI3K-Akt) signaling pathway included GYS1 and ERBB4 (p = 0.015). CPT1B, ADCY2, and GYS1 were identified as the genes significantly enriched in the insulin resistance signaling pathway (p = 0.048). LPL was the only gene significantly enriched in the cholesterol metabolism pathway (p = 0.049). Genes showing a tendency toward significant enrichment in the peroxisome-proliferator-activated receptor (PPAR) signaling pathway included ACSL4, CPT1B, SCD1, and LPL (p = 0.051). These interconnected cascades improve insulin sensitivity, stimulate triglyceride (TG) hydrolysis, and modulate n3-PUFA levels. Supplementation with AOK enhances n3-PUFA content by accelerating TG breakdown while simultaneously restraining FA oxidation in SADT. Consequently, AOK supplementation can be effectively used to enhance the nutritional value of cashmere goat meat through improved n3-PUFA deposition in SADT.