Metabolic profiling of serum from dogs with pituitary-dependent hyperadrenocorticism

Effect of leukoreduction on the omics phenotypes of canine packed red blood cells during refrigerated storage

BACKGROUND

Red blood cell (RBC) storage promotes biochemical and morphological alterations, collectively referred to as storage lesions (SLs). Studies in humans have identified leukoreduction (LR) as a critical processing step that mitigates SLs. To date no study has evaluated the impact of LR on metabolic SLs in canine blood units using omics technologies.

OBJECTIVE

Compare the lipid and metabolic profiles of canine packed RBC (pRBC) units as a function of LR in fresh and stored refrigerated (up to 42 days) units.

ANIMALS

Packed RBC units were obtained from 8 donor dogs enrolled at 2 different Italian veterinary blood banks.

STUDY DESIGN AND METHODS

Observational study. A volume of 450 mL of whole blood was collected using Citrate-Phosphate-Dextrose-Saline-Adenine-Glucose-Mannitol (CPD-SAGM) transfusion bags with a LR filter to produce 2 pRBC units for each donor, without (nLR-pRBC) and with (LR-pRBC) LR. Units were stored in the blood bank at 4 ± 2°C. Sterile weekly samples were obtained from each unit for omics analyses.

RESULTS

A significant effect of LR on fresh and stored RBC metabolic phenotypes was observed. The nLR-pRBC were characterized by higher concentrations of free short and medium-chain fatty acids, carboxylic acids (pyruvate, lactate), and amino acids (arginine, cystine). The LR-pRBC had higher concentrations of glycolytic metabolites, high energy phosphate compounds (adenosine triphosphate [ATP]), and antioxidant metabolites (pentose phosphate, total glutathione).

CONCLUSION AND CLINICAL IMPORTANCE

Leukoreduction decreases the metabolic SLs of canine pRBC by preserving energy metabolism and preventing oxidative lesions.

Metabolomic Abnormalities in Serum from Untreated and Treated Dogs with Hyper- and Hypoadrenocorticism

The adrenal glands play a major role in metabolic processes, and both excess and insufficient serum cortisol concentrations can lead to serious metabolic consequences. Hyper- and hypoadrenocorticism represent a diagnostic and therapeutic challenge. Serum samples from dogs with untreated hyperadrenocorticism (n = 27), hyperadrenocorticism undergoing treatment (n = 28), as well as with untreated (n = 35) and treated hypoadrenocorticism (n = 23) were analyzed and compared to apparently healthy dogs (n = 40). A validated targeted proton nuclear magnetic resonance (¹H NMR) platform was used to quantify 123 parameters. Principal component analysis separated the untreated endocrinopathies. The serum samples of dogs with untreated endocrinopathies showed various metabolic abnormalities with often contrasting results particularly in serum concentrations of fatty acids, and high- and low-density lipoproteins and their constituents, which were predominantly increased in hyperadrenocorticism and decreased in hypoadrenocorticism, while amino acid concentrations changed in various directions. Many observed serum metabolic abnormalities tended to normalize with medical treatment, but normalization was incomplete when compared to levels in apparently healthy dogs. Application of machine learning models based on the metabolomics data showed good classification, with misclassifications primarily observed in treated groups. Characterization of metabolic changes enhances our understanding of these endocrinopathies. Further assessment of the recognized incomplete reversal of metabolic alterations during medical treatment may improve disease management.