Shipping stress is an economic problem because of its effect on meat quality. Because shipping increases plasma cortisol and pyridoxal 5'-phosphate interacts with steroid hormones, we examined the interaction between adrenocorticotropic hormone (ACTH) and vitamin B-6 metabolism in pigs. Six crossbred pigs with ear vein catheters received 50 IU of porcine ACTH intravenously at 3-h intervals from 0800 to 2100 h on d 1-3 and 100 IU intramuscularly at 0800, 1400 and 2000 h on d 6 and 7. Controls received saline. ACTH had no effect on pyridoxal 5'-phosphate in adrenal tissue but decreased pyridoxamine 5'-phosphate from 6.1 +/- 0.7 to 4.7 +/- 1.0 nmol/g (P < 0.05). Adrenal pyridoxal and pyridoxamine concentrations were 0.4 +/- 0.1 nmol/g in controls and 1.1 +/- 0.3 and 1.3 +/- 0.5 nmol/g, respectively, in ACTH-treated pigs (P < 0.01). Pyridoxal 5'-phosphate phosphatase activity [median (25-75 percentile value)] at pH 7.4 in adrenal tissue was 66.6 (47.8-75.5) nmol/(g. min) in the controls and 764 (626-771) in the ACTH-treated pigs (P < 0.01). There was no significant difference in pyridoxal kinase activity. However, kinase activity in the adrenals was about twice as high as in other tissues. These data suggest an active turnover of vitamin B-6 in adrenal tissue.

Download full-text PDF

Source
http://dx.doi.org/10.1093/jn/129.10.1905DOI Listing

Publication Analysis

Top Keywords

pyridoxal 5'-phosphate
12
adrenal tissue
12
+/- nmol/g
12
adrenocorticotropic hormone
8
vitamin b-6
8
+/- +/-
8
acth-treated pigs
8
pigs 001
8
kinase activity
8
adrenal
5

Similar Publications

Pyridoxal 5'-phosphate (PLP)-dependent enzymes are involved in many cellular processes and possess unequalled catalytic versatility. Rational design through site-directed mutagenesis is a powerful strategy for creating tailor-made enzymes for a wide range of biocatalytic applications. PLP-dependent methionine γ-lyase (MGL), which degrades sulfur-containing amino acids, is an encouraging enzyme for many therapeutic purposes - from combating bacterial resistant strains and fungi to antitumor activity.

View Article and Find Full Text PDF

Background: Dietary supplementation for beef cattle, using natural plant extracts, such as oregano essential oil (OEO), has proven effective in enhancing growth performance, beef production quantity and quality, and ensuring food safety. However, the precise mechanisms underlying these effects remain unclear. This study investigated the impact of OEO on carcass traits, muscle fiber structure, meat quality, oxidative status, flavor compounds, and gene regulatory mechanisms in the longissimus thoracis (LT) muscles of beef cattle.

View Article and Find Full Text PDF

This work presents the development of an amperometric biosensor for detecting aspartate aminotransferase (AST) activity in biological fluids using a platinum disk electrode as the working transducer. Optimal concentrations of substrates (aspartate, α-ketoglutarate) and the coenzyme (pyridoxal phosphate) were determined to ensure efficient biosensor operation. A semi-permeable poly-m-phenylenediamine membrane was applied to enhance selectivity against electroactive interferents.

View Article and Find Full Text PDF

Mutations in the SLC25A38 gene are responsible for the second most common form of congenital sideroblastic anemia (CSA), a severe condition for which no effective treatment exists. We developed and characterized a K562 erythroleukemia cell line with markedly reduced expression of the SLC25A38 protein (A38-low cells). This model successfully recapitulated the main features of CSA, including reduced heme content and mitochondrial respiration, increase in mitochondrial iron, ROS levels and sensitivity to oxidative stress.

View Article and Find Full Text PDF

The first monomeric pyridoxal-5'-phosphate (PLP)-dependent transaminase from a marine, aromatic-compound-degrading, sulfate-reducing bacterium Tol2, has been studied using structural, kinetic, and spectral methods. The monomeric organization of the transaminase was confirmed by both gel filtration and crystallography. The PLP-dependent transaminase is of the fold type IV and deaminates D-alanine and ()-phenylethylamine in half-reactions.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!