Trace element status in canine endocrine diseases.

A balanced trace element status is essential for the optimal functioning of all organisms. However, their concentrations are often altered in diverse medical conditions. This study investigated the trace element profiles in plasma samples of dogs with endocrine diseases and used chemometric techniques to explore their associations with biochemical data. Thirteen elements (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se and Zn) were measured in 40 dogs with hyperadrenocorticism (HAC), 29 dogs with diabetes mellitus (DM), 11 dogs with hypothyroidism (HT) and 30 control dogs using inductively coupled plasma mass spectrometry (ICP-MS). Statistically significant differences were observed for As, Cu, Mo, Se and Zn. In comparison with the control group, the HT patients had higher As and lower Se levels, while the HAC group had higher concentrations of Mo. All three disease groups had higher Cu and Zn concentrations than the control group, with the DM group having higher Cu concentrations and the HAC group higher Zn concentrations than the other endocrinopathy groups. The chemometric analysis revealed distinctive association patterns for discriminating each pathology group and the control group. Moreover, the analysis revealed the following associations: Mo with glucose levels and Cu with fructosamine levels in the DM group, As with cortisol levels in the HAC group, and Se with TT4 levels and As with TSH levels in the HT group. The study findings provide valuable insights into the complex relationships between trace elements and endocrinopathies, elucidating the associations with biochemical markers in these diseases. Larger-scale studies are necessary to fully understand the observed relationships and explore the potential clinical applications.

Changes in plasma hormone levels following lipopolysaccharide injection in rabbits.

Lipopolysaccharide (LPS) is an endotoxin comprising part of the cell wall of Gram-negative bacteria. It is able to induce a septic state and the release of several pro-inflammatory cytokines that are known to be responsible for hormonal changes in humans and animals. The aim of this study was to evaluate changes in plasma adrenocorticotrophic hormone (ACTH), corticosterone and cortisol levels in a rabbit model in which sepsis was induced by the intravenous administration of LPS. The possible involvement of several protein kinases, namely protein kinase A (PKA), C (PKC) and mitogen-activated protein kinases (MAPKs), and proteasome was also assessed. The results indicated that LPS induced significant increases in plasma ACTH, corticosterone and cortisol concentrations in rabbits. Moreover, protein kinases and proteasome seemed to mediate the hormone response to LPS as treatment with specific inhibitors prior to LPS administration was able to reduce, delay, or, in some cases, inhibit the hormone increases. The findings may help to construct strategies to protect and treat animals with endotoxaemia.

Lipopolysaccharide induces inhibition of galactose intestinal transport in rabbits in vitro.

BACKGROUND/AIMS: Previous studies from our laboratory have revealed impaired intestinal absorption of D-galactose in lipopolysaccharide-treated rabbits. The aim of the present work was to examine the effect of LPS on D-galactose intestinal absorption in vitro. METHODS: D-galactose intestinal transport was assessed employing three techniques: sugar uptake in rings of everted jejunum, transepithelial flux in Ussing-type chambers and transport assays in brush border membrane vesicles. The level of expression of the Na(+)/D-galactose cotransporter (SGLT1) was analyzed by Western blot. RESULTS: LPS decreased the mucosal D-galactose transport in rabbit jejunum but a preexposition to the endotoxin was required. LPS affected the Na(+)-dependent transport system by increasing the apparent Km value without affecting the Vmax. It also decreased the Na(+), K(+)-ATPase activity. However, it did not inhibit neither the uptake of D-galactose by brush border membrane vesicles nor modified the SGLT1 protein levels in the brush border, suggesting an indirect endotoxin effect. This inhibitory effect, was reduced by selective inhibitors of Ca(2+)-calmodulin (W13), protein kinase C (GF 109203X), p38 mitogen-activated protein kinase (SB 203580), c-Jun N-terminal kinase (SP 600125) and mitogen extracellular kinase (U 0126). CONCLUSION: LPS inhibits the mucosal Na(+)-dependent D-galactose intestinal absorption and the Na(+), K(+)-ATPase activity when it is added to the tissue. Intracellular processes related to protein kinases seem to be implicated in the endotoxin effect.

Protein kinases, TNF-{alpha}, and proteasome contribute in the inhibition of fructose intestinal transport by sepsis in vivo.

Lipopolysaccharide (LPS) endotoxin is a causative agent of sepsis. The aim of this study was to examine LPS effects on intestinal fructose absorption and to decipher mechanisms. Sepsis was induced by intravenous injection of LPS in rabbits. The ultrastructural study and DNA fragmentation patterns were identical in the intestine of LPS and sham animals. LPS treatment reduced fructose absorption altering both mucosal-to-serosal transepithelial fluxes and uptake into brush border membrane vesicles (BBMVs). Cytochalasin B was ineffective on fructose uptake, indicating that GLUT5, but not GLUT2, transport activity was targeted. GLUT5 protein levels in BBMvs were lower in LPS than in sham-injected rabbits. Thus lower fructose transport resulted from lower levels of GLUT5 protein. LPS treatment decreased GLUT5 levels by proteasome-dependent degradation. Specific inhibitors of PKC, PKA, and MAP kinases (p38MAPK, JNK, MEK1/2) protected fructose uptake from adverse LPS effect. Moreover, a TNF-alpha antagonist blocked LPS action on fructose uptake. We conclude that intestinal fructose transport inhibition by LPS is associated with diminished GLUT5 numbers in the brush border membrane of enterocytes triggered by activation of several interrelated signaling cascades and proteasome degradation.

Hip dysplasia in a 6-year-old Salz ram.

A 6-year old Salz ram was presented with a history of poor body condition, progressive gait abnormalities, pelvic limb lameness, and difficulty with copulation. Based on the history, clinical signs, hip palpation, and radiography, a diagnosis of hip dysplasia, previously unreported in sheep, was made.