Association of serum calprotectin (S100A8/A9) concentrations and idiopathic hyperlipidemia in Miniature Schnauzers

Serum α1-Proteinase Inhibitor, Calprotectin, and S100A12 Concentrations in the Characterization of Pancreatitis in Dogs

Miniature Schnauzers are predisposed to develop pancreatitis, with familial hypertriglyceridemia (HTG) described as a potential risk factor. Diagnosing pancreatitis in dogs is based on the integration of serum canine-specific pancreatic lipase (cPLI) concentration, clinical presentation, and diagnostic imaging findings. However, markers of systemic inflammation and antiprotease activity have not been extensively investigated in the characterization and prognostication of pancreatitis in dogs. Serum concentrations of alpha₁-proteinase inhibitor (α₁PI; as a marker of systemic antiprotease response) and calprotectin and S100A12 (as markers of systemic inflammation) were measured in serum samples from 35 Miniature Schnauzers diagnosed with pancreatitis (serum cPLI concentration >400 μg/L, clinical signs, abdominal imaging findings). These markers were evaluated for possible associations with patient characteristics, clinical presentation, risk factors for pancreatitis, and outcome. The study showed that biomarkers of systemic inflammation and antiprotease activity are commonly increased in Miniature Schnauzers with pancreatitis. Whereas serum calprotectin and S100A12 concentrations were found to have limited utility in differentiating pancreatitis presentations, serum α₁PI concentrations and potentially also the serum calprotectin-to-S100A12 ratio might be non-invasive surrogate markers of disease severity in dogs with pancreatitis.

S-100 Proteins: Basics and Applications as Biomarkers in Animals with Special Focus on Calgranulins (S100A8, A9, and A12)

S100 proteins are a group of calcium-binding proteins which received this name because of their solubility in a 100% saturated solution of ammonium sulphate. They have a similar molecular mass of 10-12 KDa and share 25-65% similarity in their amino acid sequence. They are expressed in many tissues, and to date 25 different types of S100 proteins have been identified. This review aims to provide updated information about S100 proteins and their use as biomarkers in veterinary science, with special emphasis on the family of calgranulins that includes S100A8 (calgranulin A; myeloid-related protein 8, MRP8), S100A9 (calgranulin B; MRP14), and S100A12 (calgranulin C). The proteins SA100A8 and S100A9 can be linked, forming a heterodimer which is known as calprotectin. Calgranulins are related to the activation of inflammation and the immune system and increase in gastrointestinal diseases, inflammation and sepsis, immunomediated diseases, and obesity and endocrine disorders in different animal species. This review reflects the current knowledge about calgranulins in veterinary science, which should increase in the future to clarify their role in different diseases and potential as biomarkers and therapeutic targets, as well as the practical use of their measurement in non-invasive samples such as saliva or feces.

Is canine calprotectin in serum stabile after storage at low temperature?

BACKGROUND

In human and veterinary medicine calprotectin is most widely used in diagnosing different gastro-intestinal diseases. The aim of this study was to assess the stability of canine calprotectin (cCP) in serum after storage at low temperatures and imprecision of the method.

METHODS

Blood samples were collected from dogs with different clinical diagnoses. Twenty-two dogs were included in this study. Calprotectin concentration was measured 4 hours after serum separation (T0), and after being frozen at - 80 °C for 8 (T1) and 16 weeks (T2). The maximum permissible difference (MPD) was derived from the equation for calculating total error (TE) TE = %Bias + (1.96 x %CV), where bias and coefficient of variation (CV) were defined by the manufacturer. The dogs enrolled in this study were patients admitted during the morning (9-12 a.m.), on the day the first measurement was performed. All sample analysis for determination of stability were done in duplicates. For determination of within-run precision, the two patients' serum samples were analyzed in 20 replicates. Imprecision was assessed by analyzing 20 replicates on one plate on two samples where high and low concentrations were anticipated.

RESULTS

The calculated value of MPD was 32.52%. Median calprotectin concentrations were higher at T1 114.08 μg/L (IQR = 55.05-254.56) and T2 133.6 μg/L (IQR = 100.57-332.98) than at T0 83.60 μg/L (IQR = 50.38-176.07). Relative and absolute bias at T1 (49.3%; 45.98 μg/L) and T2 (109.93%; 94.09 μg /L) have shown that calprotectin concentrations increase after long term storage at - 80 °C.

CONCLUSION

The results of the present study indicate that c-CP was not stable for 16 weeks at low storage temperature (- 80 °C). Considering the observed change in the concentration of c-CP at T1, a storage time of 8 weeks should be safely applied. The method imprecision was not satisfactory, especially in the lower concentration range.

Associations among serum insulin, calprotectin, and C-reactive protein concentrations in Miniature Schnauzers with idiopathic hyperlipidemia before and after feeding an ultra-low-fat diet

Background

Miniature Schnauzers (MS) commonly have idiopathic hypertriglyceridemia (HTGL), which is associated with insulin resistance (IR) and a subclinical inflammatory phenotype.

Objectives

Determine the association between indicators of IR and inflammatory biomarkers in MS with and without HTGL and identify how indicators of IR are affected by dietary intervention in MS with HTGL.

Animals

Seventy MS with HTGL and 79 MS without HTGL. In addition, 15 MS with HTGL were placed on a low‐fat diet.

Methods

Serum concentrations of triglycerides, cholesterol, calprotectin, insulin, and glucose were compared between groups.

Results

Serum glucose and calprotectin concentrations (shown to be higher in MS with HTGL than in MS without HTGL) were inversely correlated (ρ = −.28; P < .001). After dietary intervention, median serum insulin concentrations were 8.1 mU/L compared to 20.8 mU/L before dietary intervention (P = .06). Dogs with complete resolution of HTGL after dietary intervention (5 dogs) had significantly lower serum insulin concentrations compared to baseline (P = .03).

Conclusion and Clinical Importance

The subclinical inflammatory phenotype in MS with HTGL appears to be associated with IR. Resolution of HTGL by dietary intervention is associated with a decrease in serum insulin concentrations. The implication of the increase in serum calprotectin concentrations after resolution of HTGL warrants further study.

Association of serum calprotectin (S100A8/A9) concentrations and idiopathic hyperlipidemia in Miniature Schnauzers

BACKGROUND

Idiopathic hyperlipidemia (IH) is a common condition in Miniature Schnauzers (MS). Studies in people have linked IH to low-grade inflammation, which plays an important role in the pathogenesis of IH complications. The role of inflammation in MS with IH is unknown.

OBJECTIVE

Evaluation of the inflammatory markers serum calprotectin and S100A12 in MS with IH and in response to dietary intervention for IH management.

ANIMALS

One-hundred fifty clinically healthy MS.

METHODS

Serum triglyceride, cholesterol, calprotectin, and S100A12 concentrations were measured before and after placing the dogs on an ultra-low fat diet.

RESULTS

Hypertriglyceridemia (HTGL, P < .001) and hypercholesterolemia (HCHOL, P = .01) were independently associated with increased serum calprotectin but not S100A12 concentrations. Compared to normolipidemic MS, serum calprotectin concentrations were significantly higher in MS with HTGL (P < .001) or combined hyperlipidemia (P = .02), but not those with isolated HCHOL (P = 1.0000). Presence (P = .005) and severity (P = .003) of HTGL and serum cholesterol concentrations (P = .04) decreased in MS with IH within 14-26 weeks after being placed on the ultra-low fat diet, but neither serum calprotectin nor S100A12 concentrations changed significantly with this dietary intervention.

CONCLUSIONS AND CLINICAL IMPORTANCE

Subclinical (low-grade) inflammation appears to be present in some MS with IH, and an ultra-low fat diet does not decrease serum concentrations of inflammatory proteins in those dogs. Whether this presumed inflammatory phenotype in MS with IH is associated with the development of IH complications (eg, insulin resistance) requires further research.