Expression of corticosteroid hormone receptors, prereceptors, and molecular chaperones in hypothalamic-pituitary-adrenal axis and adipose tissue after the administration of growth promoters in veal calves

Plasma Lipolysis and Changes in Plasma and Cerebrospinal Fluid Signaling Lipids Reveal Abnormal Lipid Metabolism in Chronic Migraine

Background

Lipids are a primary storage form of energy and the source of inflammatory and pain signaling molecules, yet knowledge of their importance in chronic migraine (CM) pathology is incomplete. We aim to determine if plasma and cerebrospinal fluid (CSF) lipid metabolism are associated with CM pathology.

Methods

We obtained plasma and CSF from healthy controls (CT, n = 10) or CM subjects (n = 15) diagnosed using the International Headache Society criteria. We measured unesterified fatty acid (UFA) and esterified fatty acids (EFAs) using gas chromatography-mass spectrometry. Glycerophospholipids (GP) and sphingolipid (SP) levels were determined using LC-MS/MS, and phospholipase A₂ (PLA₂) activity was determined using fluorescent substrates.

Results

Unesterified fatty acid levels were significantly higher in CM plasma but not in CSF. Unesterified levels of five saturated fatty acids (SAFAs), eight monounsaturated fatty acids (MUFAs), five ω-3 polyunsaturated fatty acids (PUFAs), and five ω-6 PUFAs are higher in CM plasma. Esterified levels of three SAFAs, eight MUFAs, five ω-3 PUFAs, and three ω-6 PUFAs, are higher in CM plasma. The ratios C20:4n-6/homo-γ-C20:3n-6 representative of delta-5-desaturases (D5D) and the elongase ratio are lower in esterified and unesterified CM plasma, respectively. In the CSF, the esterified D5D index is lower in CM. While PLA₂ activity was similar, the plasma UFA to EFA ratio is higher in CM. Of all plasma GP/SPs detected, only ceramide levels are lower (p = 0.0003) in CM (0.26 ± 0.07%) compared to CT (0.48 ± 0.06%). The GP/SP proportion of platelet-activating factor (PAF) is significantly lower in CM CSF.

Conclusions

Plasma and CSF lipid changes are consistent with abnormal lipid metabolism in CM. Since plasma UFAs correspond to diet or adipose tissue levels, higher plasma fatty acids and UFA/EFA ratios suggest enhanced adipose lipolysis in CM. Differences in plasma and CSF desaturases and elongases suggest altered lipid metabolism in CM. A lower plasma ceramide level suggests reduced de novo synthesis or reduced sphingomyelin hydrolysis. Changes in CSF PAF suggest differences in brain lipid signaling pathways in CM. Together, this pilot study shows lipid metabolic abnormality in CM corresponding to altered energy homeostasis. We propose that controlling plasma lipolysis, desaturases, elongases, and lipid signaling pathways may relieve CM symptoms.

FKBP5 gene expression in skeletal muscle as a potential biomarker for illegal glucocorticoid treatment in veal calves

For the current European legislation, the chemical analysis of drug residues is the exclusive accepted method to identify animals illicitly treated with growth promoters. Glucocorticoids and their metabolites are no detectable by LC/MS-MS methods in biological fluids when the growth promoter administration is discontinued several days prior to the slaughtering. The aim of this study was to elucidate the effect on the expression of genes belonging to the glucocorticoid pathway in three types of skeletal muscle of calves treated with prednisolone or dexamethasone in combination with estradiol. A gene expression change of glucocorticoid receptors (NR3C1 and NR3C2), their chaperones molecules (FKBP prolyl isomerase 4 and 5, FKBP4 and 5) and pre-receptor system (hydroxysteroid 11-beta dehydrogenases 1 and 2, HSD11B1 and 2) may indicate potential biomarkers of glucocorticoid treatment. In the biceps brachii muscle, the administration of dexamethasone with estradiol increased HSD11B2 (P < 0.01) and NR3C2 (P < 0.01) gene expression, whereas prednisolone administration increased HSD11B1 transcript levels (P < 0.05). In the longissimus lumborum muscle, NR3C2 gene expression decreased following prednisolone administration (P < 0.05). FKBP5 gene expression decreased in all considered muscles of calves administered with dexamethasone and estradiol (P < 0.01), whereas increased in the longissimus lumborum (P < 0.01) and vastus lateralis (P < 0.05) muscle of prednisolone-treated group (P < 0.05). The opposite effect of dexamethasone and prednisolone appears very promising to develop a low-cost screening test, because the expression analysis of a unique gene in a given tissue may distinguish the dispensed molecules.