Ketotic cows display a different serum nonesterified fatty acid composition.

The experiments reported in this research communication aimed to compare the serum nonesterified fatty acid (NEFA) composition in ketotic cows and healthy cows during the perinatal period. NEFAs play significant roles in etiology and pathology of ketosis. We hypothesized that ketotic cows will display a different serum NEFA composition compared to healthy controls, and fatty acid related indicators for ketosis prediction can be screened. Pre-partum healthy cows were recruited, and blood samples were collected on -7, 3, 7, 14 and 21 d postpartum. Cows were further divided into a healthy control group (C group, n = 6) and a ketosis group (K group, n = 6) if blood ß-hydroxybutyric acid levels exceeded 1.2 mm during the experiment. NEFA composition was then analyzed by means of Gas Chromatography-Mass Spectrometer (GC-MS). Only C12 : 0% was significantly higher in C group than K group on 7 d pre-partum (P < 0.05), when the cows were not diagnosed with ketosis. Five fatty acids displayed statistical differences in composition between C and K group (P < 0.05), namely C12 : 0, C16 : 0, C17 : 0, C18 : 1n9 and C22 : 1n9. Saturates%, unsaturates%, mono-unsaturates% and saturates/unsaturates were also different between C and K group (P < 0.05). Of note, C18 : 1n9/C12 : 0 and C18 : 1n9/C22 : 1n9 in K group were significantly higher than those in controls on 7 d pre-partum (P < 0.05). It is suggested that the ratios show potential as indicators for prediction of ketosis.

Significant changes in ITIH4, AHSG, ORM1, and CD46 content in milk fat globule membrane proteins of ketotic dairy cows.

High concentrations of non-esterified fatty acid (NEFA) and ß-hydroxybutyrate (BHBA) in cows' blood caused by ketosis are associated with inflammatory states. We hypothesised that ketosis in postparturient dairy cows would result in altered levels on inflammation-related proteins not only in plasma but also in the milk fat globule membranes (MFGM). Thirty cows were selected from a dairy farm in Heilongjiang, China. Inflammatory milk fat globule membrane proteins were detected using ELISA kits, and a fully automatic biochemical analyser was used to measure the concentrations of BHBA, NEFA, glucose (GLU) and triglyceride (TG) in plasma. MFGM protein from milk of ketotic cows contained significantly different concentrations of acute-phase response proteins (complement C3 (C3), prothrombin (F2), alpha-1-acid glycoprotein (ORM1), inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4), alpha-2-HS-glycoprotein (AHSG), complement C9 (C9), complement regulatory protein variant 4 (CD46)) in comparison with milk from non-ketotic cows. Blood concentrations of C3, complement C9 (C9), tumour necrosis factor α (TNFα), MFGM C3, monocyte differentiation antigen CD14 (CD14) and ORM1 levels were correlated with energy balance. ITIH4 and CD46 increased, and AHSG and ORM1 decreased before the onset of ketosis. These biomarkers offer potential as predictors and monitors of ketosis in at-risk cows.

Influence of oleic acid in different solvent media on BRL 3A cell growth and viability.

Oleic acid (OA) is widely used in pathology studies of hepatocellular lipid deposition. Identifying the effects of different solvents on OA-induced liver lipid deposition would be beneficial for studies on hepatocytes. We treated BRL 3A cells with OA dissolved in different solvents. After 12 h incubation, cell viability was assessed using MTT assays. Reactive oxygen species (ROS), triglyceride (TG) and total cholesterol (TC) counts, and the expression level of glucose regulated protein (GRP78), sterol regulatory element binding protein (SREBP-1C) and fatty acid synthase (FAS) were analyzed. Water, PBS and DMSO were disadvantageous to the dissolution of OA and did not cause an OA-induced response in hepatocytes. In the alcohol+OA-treated cells, the severe ER stress, oxidative stress and cellular fat deposition were significantly increased. BSA promoted cell growth and the cells treated with 1.2% BSA+OA showed a lower grade TG and endoplasmic reticulum stress compared with KOH+OA and alcohol+OA treatments. KOH had no significant influence on BRL 3A cells viability. When treated with OA dissolved in KOH, BRL 3A cells showed a typical hepatocyte damage. KOH was considered the suitable choice for an OA solvent for BRL 3A cells in hepatic lipidosis research.