High Levels Of Non-esterified Fatty Acids Research Articles

The Influence of Energy Balance, Lipolysis and Ketogenesis on Metabolic Adaptation in Cows Milked Twice and Three Times Daily

Increasing milk production requires increasing milking frequency (MF) from two times daily (2X) to three (3X) or more. High milk production leads to negative energy balance (NEB) and homeorhesis, characterized by lipolysis, ketogenesis, and endocrinological changes. The relationship among energy balance (EB), lipolysis, and ketogenesis with endocrine and metabolic parameters in blood of cows milked 2X and 3X daily was studied. Holstein Friesian cows milked 2X (n = 45) and 3X (n = 45) were analyzed, with approximately 50% of cows in each group in positive EB (PEB) and 50% in NEB. After determining EB, blood samples were collected from all cows and blood serum was analyzed for non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHB), glucose (GLU), cholesterol (CHOL), triglycerides (TGC), total bilirubin (TBIL), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), calcium (Ca), inorganic phosphate (P), total protein (TPROT), albumin (ALB), urea, insulin (INS), T3, T4, and cortisol (CORT), and the RQUICKIBHB index of insulin resistance was calculated. Cows milked 3X in NEB represent a special cluster that partially overlaps with cows milked 2X in NEB and has no contact points with cows in PEB. Cows milked 3X had higher levels of NEFA, BHB, AST, GGT, TBIL, and CORT and lower levels of GLU, Ca, INS, and T4. Cows milked 3X in NEB had higher levels of NEFA, BHB, AST, GGT, TBIL, and CORT and lower levels of GLU, CHOL, TGC, TPROT, P, INS, RQUICKIBHB, and T3 compared with cows milked 2X in NEB and cows in PEB. In cows milked 3X, lipolysis and ketogenesis were much more prominent, and EB levels were lower, implying a pronounced shift in homeorhesis. Metabolic and endocrinology parameters were determined mainly by the values of EB, NEFA, and BHB in cows milked 3X in NEB compared with other categories of cows. The results confirm the peculiarity of metabolic adaptation in cows with increased MF, characterized not only by differences in the concentration of metabolites but also in their interactions.

Influence of weaning management at 30, 75 and 180 days of age on non-esterified fatty acids and reproductive performance in beef cows.

This study aimed to investigate the effect of age at weaning of calves on non-esterified fatty acids (NEFA) and reproductive parameters of beef cows. Animals (n = 65) were randomly assigned to three treatments after calving: hyper-early weaning (W30) at 32 ± 0.89 days, early weaning (W75) at 77 ± 0.95 days, and conventional weaning (W180) at 183 ± 0.82 days. Body weight (BW) and body condition score (BCS) were evaluated at parturition (AP) and at 30, 45, 64, 81, 100 and 115 days postpartum (dPP). Blood samples were collected to analyze NEFAlevels and progesterone (P4) at 30, 45, 64 and 81 dPP. Higher BW and BCS were observed from 64 to 115 dPP in W30 cows than W180 ones (p < 0.05). Cows subjected to W30 condition had higher levels of NEFA at 30 dPP compared to 64 and 81 dPP (p < 0.05). We also observed that cows from W180 group showed decreased levels of NEFA at 30 dPP compared to 45 (p < 0.01) and 64 dPP (p < 0.05). The highest P4 level was observed at 64 dPP in W30 cows compared to W75 and W180 (p < 0.05). We also observed higher CR of W30 (86%) compared to W180 (47%) at 45 dPP (p < 0.05). The overall pregnancy rate (PR) was higher for W30 (95.5%) than W180 (73.9%). In addition, higher BW at calving and P4 levels at 30 dPP were positively correlated with the possibility of pregnancy (p < 0.05). Improvement in BW and BCS were observed in cows subjected to hyper-early weaning management. However, levels of NEFA decreased as the postpartum period progressed. We concluded that cows who weaned calves hyper-early have greater chances of increasing cyclicity and PRs.

Metabolism of fatty acids in follicular cells, oocytes, and blastocysts.

Fatty acids (FA) are one of the substrates that can be oxidized for energy production. The blood concentration of all types of FA varies according to different nutrition conditions, and follicular fluid levels are generally in line with serum levels. Elevated levels of FA, especially non-esterified fatty acids (NEFA), are commonly found in females with metabolic issues, which are often related to subfertility in many species including humans, pigs, cattle, and mice. Long-time exposure to an excessive quantity of fatty acids impairs the cell structure and functions causing injuries in tissues and organs, resulting in lipotoxicity and eventually hampering health and fertility. High levels of saturated NEFA can have detrimental effects on granulosa cells, oocyte quality, and embryo development. Although the harmful effects of FA are established in reproductive tissues, how granulosa cells and cumulus cells respond and cooperate with oocytes when exposed to NEFA requires further understanding. This review provides a summary of the adverse impacts of exposure to NEFA during in vitro maturation on oocytes, follicular cells, and embryos. A comprehensive understanding of the effects of NEFA on oocytes in vitro would improve our understanding of the impacts of natural exposure in vivo.Lay summaryExposure to excess FAs affects the health of eggs, early embryos, and children born from these. The way different cell types react to excess FAs has not been studied very extensively, especially in pigs which provide a good model to investigate the impact of nutrition on the ovaries in humans. This review also looks at the way cells surrounding the egg react to FAs to help our understanding of the impact of excess fatty acids on female fertility.

Early Warning for Ovarian Diseases Based on Plasma Non-esterified Fatty Acid and Calcium Concentrations in Dairy Cows.

Inactive ovaries (IO) and ovarian (follicular or luteal) cysts (FC or LC) are two common ovarian diseases leading to infertility in dairy cattle. Both disorders are associated with altered metabolites and hormones. There are currently no known effective biomarkers that can be used for early diagnosis of ovarian diseases. The purpose of this study was to identify the plasma biomarkers of ovarian diseases in Holstein dairy cows that facilitate an early diagnosis of the diseases and control its progression. The experiment was performed from 3 weeks postpartum and last for 7 weeks. Seventy-six multiparous Holstein cows (mean age, 4.36 years; weight, 635.63 kg) were divided into healthy control group (HC, n = 22), FC group (n = 18), LC group (n = 18) and IO group (n = 18) by rectal palpation or ultrasonography during the last 2 weeks before trial end. Blood was collected via tail vein for measurement of plasma energy metabolites, liver function indicators, minerals, and hormones at 3 and 8 weeks postpartum. Data were analyzed by Mann-Whitney U, Kruskal-Wallis, Spearman correlation, binary logistic regression analysis and receiver operating characteristic analysis, where applicable. At 8 weeks postpartum, FC cows had a more severe body condition score loss and these had greater levels of non-esterified fatty acids (NEFA) and estradiol, and lesser levels of alanine aminotransferase (ALT), progesterone and insulin-like growth factor 1 (IGF-1) levels than HC cows (P < 0.05). LC cows had a lower milk yield, higher NEFA and progesterone levels, and lower calcium, phosphorus and magnesium levels than HC cows (P < 0.05). IO cows had a lower body condition score, higher NEFA levels, and lower ALT, calcium, phosphorus, magnesium, estradiol, progesterone and IGF-1 levels than HC cows (P < 0.05). At 3 weeks postpartum, cows with ovarian diseases had greater (P < 0.05) concentrations of NEFA, and lesser concentrations of ALT, calcium, phosphorus and IGF-1 than HC cows. Early warning values for ovarian diseases were plasma NEFA concentrations >0.50 mmol/L, or calcium concentrations <2.02 mmol/L. Therefore, plasma NEFA and calcium could be used as early-warning indicators for ovarian diseases in dairy cows.

Fatty acids may influence insulin dynamics through modulation of albumin‐Zn2+ interactions

AbstractInsulin is stored within the pancreas in an inactive Zn2+‐bound hexameric form prior to release. Similarly, clinical insulins contain Zn2+ and form multimeric complexes. Upon release from the pancreas or upon injection, insulin only becomes active once Zn2+ disengages from the complex. In plasma and other extracellular fluids, the majority of Zn2+ is bound to human serum albumin (HSA), which plays a vital role in controlling insulin pharmacodynamics by enabling removal of Zn2+. The Zn2+‐binding properties of HSA are attenuated by non‐esterified fatty acids (NEFAs) also transported by HSA. Elevated NEFA concentrations are associated with obesity and type 2 diabetes. Here we present the hypothesis that higher NEFA levels in obese and/or diabetic individuals may contribute to insulin resistance and affect therapeutic insulin dose‐response profiles, through modulation of HSA/Zn2+ dynamics. We envisage this novel concept to have important implications for personalized treatments and management of diabetes‐related conditions in the future.

Sirtuin 3 inhibits nuclear factor-κB signaling activated by a fatty acid challenge in bovine mammary epithelial cells

Susceptibility to mastitis is highest during the peripartal (transition) period and is often concomitant with other comorbidities such as ketosis. Although infection with pathogenic microorganisms and immune-dysfunction around calving clearly play key roles in mastitis development, other metabolic factors also contribute. Sirtuin 3 (SIRT3), a mitochondrial deacetylase regulating energy and redox homeostasis, antagonizes the lipotoxic effects of nonesterified fatty acids (NEFA). Thus, we hypothesized that increases in circulating NEFA concentrations, as observed in the transition period, provokes inflammatory responses that can be reversed via activation of SIRT3. Here we aimed to study (1) proinflammatory NF-κB signaling and SIRT3 abundance in mammary tissue of ketotic cows and healthy controls, and (2) the effect of SIRT3 on NF-κB activation in bovine mammary epithelial cells (BMEC) treated with high levels of NEFA. The mammary gland biopsy samples were from a previous study, which included 15 healthy cows and 15 ketotic cows. Primary BMEC were isolated from 3 healthy Holstein cows with collagenase III digestion. Purified BMEC were incubated with or without SIRT3 overexpression adenovirus for 48 h, then treated with 0, 0.6, 1.2, or 2.4 mM NEFA for 24 h. Mammary tissue of ketotic cows was associated with lower protein abundance of SIRT3 along with greater NF-κB P65 phosphorylation levels (p-NF-κB P65), p-NF-κB P65:NF-κB P65 ratio, and mRNA abundance of IL1B and IL6. In BMEC, exogenous NEFA dose-dependently reduced protein abundance of SIRT3, but increased p-NF-κB P65, p-NF-κB P65:NF-κB P65 ratio, and mRNA abundance of IL1B and IL6. Compared with green fluorescent protein adenovirus vector + NEFA, overexpression of SIRT3 in NEFA-treated BMEC downregulated p-NF-κB P65 and mRNA abundance of IL1B and IL6. Immunofluorescence indicated that overexpression of SIRT3 inhibited nuclear translocation of NF-κB P65. Overall, our data demonstrated that ketosis is associated with a reduction in SIRT3 abundance and activation of NF-κB signaling in the mammary gland. In vitro data provided evidence that high NEFA concentrations inhibit SIRT3, which contributes to enhanced NF-κB signaling including nuclear translocation and a pro-inflammatory response. The data suggest a promising role of SIRT3 as a target for helping alleviate localized inflammation of the mammary gland resulting from exposure to high concentrations of NEFA.

Undernutrition-induced lipid metabolism disorder triggers oxidative stress in maternal and fetal livers using a model of pregnant sheep.

This study aimed to evaluate the oxidative status and antioxidant capacity in maternal and fetal livers upon undernutrition as well as the connection between oxidative stress and lipid metabolism disorder. Ten ewes, who were pregnant for 115days, were restricted to a 30% level of ad libitum feed intake to develop an undernourished model, while another 10 pregnant ewes were fed normally as controls. Undernutrition induced severe lipid metabolism disorder and oxidative stress in blood, maternal liver, and fetal liver. RNA-sequencing data displayed that antioxidant capacity was changed and antioxidant genes were downregulated in maternal and fetal livers of the undernourished model. Non-esterified fatty acids (NEFAs) and beta-hydroxybutyrate (BHBA) levels showed a positive correlation with oxidative indices and negative correlation with the expression of antioxidant genes both in maternal and fetal livers. Primary hepatocytes experiments confirmed that both high levels of NEFAs and BHBA could elicit oxidative stress and decrease antioxidant capacity, and the peroxisome proliferator-activated receptor alpha (PPARA)/retinoid X receptor alpha (RXRA) signaling pathway played a vital role in enhancing antioxidant capacity and relieving oxidative stress. In conclusion, maternal undernutrition induced lipid metabolism disorder, which downregulated antioxidant genes, decreased antioxidant activity, and further triggered oxidative stress both in maternal and fetal livers. Activation of PPARA/RXRA signaling could enhance antioxidant capacity and mitigate oxidative stress. Our findings contribute to protecting the pregnant mother and her fetus from oxidative stress.

The Effect of Feeding Roughages of Varying Digestibility Prepartum on Energy Status and Metabolic Profiles in Beef Cows around Parturition.

Simple SummaryGrass silages based on timothy-meadow fescue are commonly fed to pregnant beef cows during winter. As beef cows usually are given free access to roughage for rational reasons, the use of these silages has been questioned due to their relatively high nutritional value, which may result in nutrient intakes above animal requirements and, hence, a waste of resources. Therefore, other roughage alternatives are requested, but their effects on cow intake and energy status before calving must be evaluated before applied in practice. Four diets based on timothy-meadow fescue silage, festulolium silage plus urea, reed canarygrass silage or barley straw supplemented with urea and rapeseed meal were fed in free access to mature pregnant beef cows. Timothy-meadow fescue and festulolium diets resulted in overfeeding of energy and protein and in body weight and body condition gains, whereas the opposite was observed for cows fed the other two diets. Hence, reed canarygrass or barley straw supplemented with urea and rapeseed meal prepartum may be suitable alternatives to the traditional timothy-meadow fescue diet, if cows are able to regain lost BCS during the grazing period, and may reduce winter feed costs of the cow-calf producer due to the low intakes of these diets.Resource efficient winter-feeding of mature pregnant beef cows requires knowledge of how different roughage-based feeding strategies affect cow intake and energy status. Four diets based on traditional timothy-meadow fescue silage (TM), festulolium silage plus urea (FE), reed canarygrass silage (RC) or barley straw supplemented with urea and rapeseed meal (BR), were fed ad libitum for 16 weeks prepartum to 36 Hereford cows. Postpartum, cows were fed the same diet before release on pasture. Individual data on cow intake, changes in body weight (BW), body condition score (BCS) and plasma metabolites, calf birth and weaning weights were recorded. The TM and FE diets resulted in increased BW and BCS prepartum (p < 0.001), while the RC and BR diets resulted in a catabolic state, as indicated by a loss of BCS, lower insulin levels and higher non-esterified fatty acid levels in cows fed BR (p < 0.001). There were no dietary effects on calf parameters (p > 0.29). Feeding RC or BR prepartum might be a possible alternative to traditional timothy-meadow fescue silage if cows are allowed to regain lost BCS during the grazing period. The influence on cow reproductive- and calf performance should be considered before making this management change.

Hot Water Extract of Vaccinium corymbosum Increases Endurance Exercise Capacity by Improving Fatty Acid β-Oxidation and Antioxidant Defense System in Mice

The aim of this study was to evaluate the effects of water extract from Vaccinium corymbosum (VCW) on endurance exercise capacity. Exhaustive swimming time in the exercise and orally administered VCW group (Ex-VCW) was significantly increased compared to that of the exercise only group (Ex-CON). Compared to the Ex-CON group, the Ex-VCW group displayed lower lactate and higher non-esterified fatty acid levels after 10 min post-exercise and exhibited increased muscular glycogen level. VCW enhanced antioxidant activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione (GSH) in the experimental group compared to those of the Ex-CON group. Muscular malondialdehyde (MDA) level in Ex-VCW group appeared to be slightly decreased compared to that of the Ex-CON group; however, this difference was not statistically significant. VCW enhanced mRNA expression levels of mitochondrial biogenesis (PGC-1α, NRF, and Tfam) and fatty acid β-oxidation (CPT-1, β-HAD, and PPAR-δ) related genes. These results suggest that VCW increases endurance exercise capacity via enhanced antioxidant activities, energy metabolism, and mitochondrial biogenesis-related gene expression.

The effects of non-esterified fatty acids and β-hydroxybutyrate on the hepatic CYP2E1 in cows with clinical ketosis.

Dairy cows with ketosis display severe oxidative stress as well as high blood concentrations of non-esterified fatty acids (NEFA) and β-hydroxybutyrate (BHB). Cytochrome P4502E1 (CYP2E1) plays an important role in the induction of oxidative stress. The aim of this study was to investigate CYP2E1 expression and activity in the liver of clinically ketotic cows (in vivo) and the effects of NEFA and BHB on CYP2E1 expression and activity in hepatocytes (in vitro). Dairy cows with clinical ketosis exhibited a low blood concentration of glucose but high concentrations of NEFA and BHB. Hepatic mRNA, protein expression, and activity of CYP2E1 were significantly higher in cows with clinical ketosis than in control cows. In vitro, both NEFA and BHB treatment markedly up-regulated the mRNA and protein expressions as well as activity of CYP2E1 in cow hepatocytes. Taken together, these results indicate that high levels of NEFA and BHB significantly up-regulate the expression and activity of hepatic CYP2E1, and may be influential in the induction of oxidative stress in cows with clinical ketosis.

High expression of cell death-inducing DFFA-like effector a (CIDEA) promotes milk fat content in dairy cows with clinical ketosis

High blood concentrations of nonesterified fatty acids (NEFA) during ketosis represent a source of fatty acids for milk fat synthesis and explain the increase in milk fat content in ketotic cows. Cell death-inducing DFFA-like effector a (CIDEA) is a lipid droplet coat protein with important roles in the regulation of milk fat synthesis and secretion in mice. Whether ketosis alters the expression of CIDEA in mammary gland tissue and the extent to which it may contribute to regulation of milk fat synthesis and secretion are unknown. Mammary gland tissue and blood samples were collected from healthy (n = 15) and clinically ketotic (n = 15) cows. Mammary epithelial cells isolated from cows were infected with CIDEA overexpression adenovirus for 48 h, treated with 0, 0.3, 0.6, or 1.2 mM NEFA for 24 h, or infected with CIDEA-silencing adenovirus for 48 h and treated with 1.2 mM NEFA for 24 h. Serum concentrations of NEFA and β-hydroxybutyrate were greater in cows with clinical ketosis, and milk production and dry matter intake were lower in cows with clinical ketosis. However, compared with healthy cows, the content of milk fat of cows with clinical ketosis was greater. Compared with healthy cows, abundance of mRNA and protein of CIDEA, fatty acid synthase (FASN), acetyl-coA carboxylase 1 (ACACA), butyrophilin (BTN1A1), and xanthine dehydrogenase (XDH) was greater in mammary tissue of cows with clinical ketosis. Overexpression of CIDEA in cultured mammary epithelial cells increased the abundance of FASN, ACACA, XDH, and BTN1A1, and increased triacylglycerol (TAG) content in mammary epithelial cells. Exogenous NEFA increased the abundance of CIDEA, FASN, ACACA, XDH, and BTN1A1, and increased TAG content in mammary epithelial cells. Importantly, knockdown of CIDEA reversed the upregulation of FASN, ACACA, XDH, and BTN1A1 abundance and TAG content induced by NEFA treatment. Overall, these data suggest that high levels of NEFA stimulate the expression of CIDEA and enhance de novo fatty acid synthesis and milk fat secretion. As such, these mechanisms explain in part the elevation of milk fat content in dairy cows with clinical ketosis.

Modified low-density lipoproteins as biomarkers in diabetes and metabolic syndrome.

Cardiovascular disease of atherosclerotic origin is the main cause of death in diabetes mellitus and metabolic syndrome. One of the mechanisms involved in such increased risk is the high incidence of lipoprotein modification in these pathologies. Increased glycosylation, oxidative stress or high non-esterified fatty acid levels in blood, among other factors, promote the modification and subsequent alteration of the properties of lipoproteins. Since the modification of low-density lipoprotein (LDL) is the triggering factor in the development of atherosclerosis, considerable research has been focused on the quantification of modified LDLs in blood to be used as biomarkers of cardiovascular risk. The present review deals with the main molecular mechanisms involved in the modification of LDL in diabetes and metabolic syndrome and briefly describe the atherogenic effects that these modified LDLs exert on the arterial wall. The possibility of using the high levels of modified LDLs or their immunocomplexes as a predictive tool for cardiovascular risk in diabetes-related pathologies is also discussed.

Non-Esterified Fatty Acids Over-Activate the TLR2/4-NF-Κb Signaling Pathway to Increase Inflammatory Cytokine Synthesis in Neutrophils from Ketotic Cows

Background/Aims: Dairy cows with clinical ketosis display a negative energy balance and high blood concentrations of non-esterified fatty acids (NEFAs), the latter of which is an important pathological factor of ketosis in cows. The aims of this study were to investigate the inflammatory status of ketotic cows and to determine whether and through what underlying mechanism high levels of NEFAs induce an inflammatory response. Methods: Proinflammatory factors and the nuclear factor kappa B (NF-κB) signaling pathway were evaluated in neutrophils from clinical ketotic and control cows, using methods including western blotting, quantitative real-time polymerase chain reaction, and enzyme-linked immunosorbent assay. In vitro, the effects of NEFAs on the NF-κB signaling pathway in cow neutrophils were also evaluated using the above experimental techniques. Results: Ketotic cows displayed low blood concentrations of glucose and high blood NEFA and β-hydroxybutyrate concentrations. Importantly, Toll-like receptor 2 (TLR2) and TLR4 expression and IκBα and NF-κB p65 phosphorylation levels in neutrophils (PMNs) were significantly higher in ketotic cows than in control cows, indicating over-activation of the TLR2/4-induced NF-κB inflammatory pathway in PMNs in ketotic cows. The blood concentrations of the inflammatory cytokines interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α) were also significantly increased in ketotic cows. Interestingly, we found that NEFAs were positively correlated with proinflammatory cytokines. In vitro, after pharmacological inhibition of TLR2 and TLR4 expression in cow neutrophils, TLR2 and TLR4 expression was significantly decreased, and the phosphorylation level of NF-κB p65 was also reduced. Cow neutrophils were treated with different concentrations of NEFAs and pyrrolidine dithiocarbamate (PDTC; an NF-κB inhibitor). High concentrations of NEFAs (0.5 and 1 mM) significantly increased TLR2 and TLR4 expression, IκBα and NF-κB p65 phosphorylation levels, NF-κB p65 transcriptional activity, and IL-6, IL-1β, and TNF-α synthesis in cow neutrophils. The inhibition of NF-κB by PDTC suppressed the NEFA-induced synthesis of proinflammatory cytokines. Conclusions: High concentrations of NEFAs can over-activate the TLR2/4-mediated NF-κB signaling pathway to induce the over-production of proinflammatory cytokines, thereby increasing inflammation in cows with clinical ketosis.

Relaciones entre calcio, ácidos grasos no esterificados, e insulina sanguínea en preparto y leche bovina perdida en el inicio de la lactancia

Introducción: El objetivo fue determinar la relación entre las concentraciones séricas de calcio (Ca2+), ácidos grasos no esterificados (AGNE) e insulina preparto con pérdidas en la producción de leche (PL) en el inicio de la lactancia.Método: Doscientas cuarenta y tres vacas Holstein-Friesian (780 ± 36 kg PV; con más de dos lactancias) fueron muestreadas por punción coccígea varias veces antes, durante y después del parto. Para cada muestreo y cada metabolito, las concentraciones séricas se estratificaron con umbrales y se relacionaron con la PL.Resultados: Cuando los niveles de Ca2+ fueron bajos 10 días antes del parto y se relacionaron con la PL a los 10 días posparto, se observó que el 77.11% de las vacas perdieron 2.20 kg de leche; mientras en el día 20, el 66.41% de las vacas perdieron 1.40 kg animal-1 día-1. Por el contrario, cuando los AGNE fueron altos 10 días antes de parto y se relacionaron con PL, 67.40% de las vacas mostraron riesgo de perder 0.80 kg, mientras que a los 20 días posparto, el 22.00% de las vacas perdieron aproximadamente 0.90 kg vaca-1 día-1. La determinación de insulina preparto baja y PL en los días 10 y 20 de lactancia indicó que 6.02% de las vacas perdieron 0.80 y 0.70 kg de leche animal-1 día-1 para los días 10 y 20 de lactancia.Conclusión: En conclusión, niveles bajos de calcio, AGNE alto e insulina baja en sangre, obtenidos 10 días antes de parto fueron asociados con pérdidas en producción de leche en los días 10 y 20 después del parto. También se observó que los niveles bajos de calcio podrían causar mayores pérdidas de leche que los niveles altos de ácidos grasos no esterificados y las concentraciones bajas de insulina preparto.

Resveratrol supplement inhibited the NF-κB inflammation pathway through activating AMPKα-SIRT1 pathway in mice with fatty liver.

Nonalcoholic fatty liver disease (NAFLD) is characterized by high levels of nonesterified fatty acids (NEFA), inflammation, and hepatic steatosis. Inflammation plays a crucial role in the development of fatty liver. Resveratrol (RSV) supplement could improve inflammatory response and hepatic steatosis, whereas the underlying mechanism was not well understood. In this study, mice fed with high-fat diet (HFD) exhibited severe hepatic injury and high blood concentrations of the inflammatory cytokines TNF-α, IL-6, and IL-1β. Hepatic NF-κB inflammatory pathway was over-induced in HFD mice. In vitro, NEFA treatment further increased NF-κB pathway activation in mice hepatocytes, which then promoted the synthesis of inflammatory cytokines. Interestingly, RSV treatment significantly inhibited overactivation of NF-κB pathway and improved hepatic steatosis. Furthermore, RSV further increased the AMP-activated protein kinaseα (AMPKα) phosphorylation and sirtuin1 (SIRT1) protein levels to inhibit overactivation of NF-κB pathway induced by HFD or high levels of NEFA. AMPKα or SIRT1 inhibition significantly decreased the improvement effect of RSV on the NF-κB pathway induced by high levels of NEFA. Taken together, these findings indicate that RSV supplement decreases the inflammatory level and improves hepatic steatosis through activating AMPKα-SIRT1 pathway. Therefore, these data suggested an important clinical application of RSV in preventing NAFLD in humans.

Body condition loss and increased serum levels of nonesterified fatty acids enhance progesterone levels at estrus and reduce estrous activity and insemination rates in postpartum dairy cows

Data from 96 Holstein Friesian cows on a commercial dairy farm were used to investigate whether body condition and serum levels of nonesterified fatty acids (NEFAs) postpartum (pp) affect progesterone (P4) levels, estrous activity, and fertility in dairy cows. The examination period started 14 days before the expected calving date and ended either when a cow was inseminated or at a maximum of 90 days pp. Body condition score (BCS; 1–5 scale) and backfat thickness (BFT) were determined every 2 weeks. Blood for analysis of NEFA and P4 concentrations was sampled weekly during the first 35 days pp and then every 48 hours until an ovulation was observed. Transrectal ultrasonography of the ovaries started at 21 days pp and was performed after blood sampling. If cows were not inseminated because of silent ovulation, sampling and ultrasonography continued on Days 7, 14, and 18 after ovulation and again every 48 hours until the next ovulation. Estrous activity was continuously measured with the Heatime estrus detection system. Pregnancy controls were performed ultrasonographically 28 and 42 days after AI. Cows with increased NEFA levels at 28 days pp had an increased risk of maintaining minimum P4 levels above 0.4 ng/mL at first recognized estrus (P = 0.03). Higher NEFA levels at Day 7 were associated with lower probability for a cow to have elevated P4 levels (≥2 ng/mL) by Day 35 pp, indicating delayed commencement of luteal activity (C-LA). Estrous activity was not influenced (P > 0.10) by minimum P4 concentrations at estrus, but more animals with C-LA until Day 35 pp showed estrous activity compared to cows without C-LA throughout this period (P = 0.006). Estrous activity was lower in cows with a low BCS 14 days pp (P = 0.02) and with a low BFT 42 days pp (P = 0.03). Moreover, the probability to exhibit estrus was reduced with higher NEFA levels at 21 days pp (P = 0.01). Eighty-five cows were inseminated and 37 (44%) got pregnant after insemination. Higher NEFA levels, especially 14, 28, and 42 days pp, were associated with lower probability to inseminate a cow. Regarding the cows that were inseminated, no influence of BCS, BFT, or NEFA levels on pregnancy per artificial insemination was found. In conclusion, cows with higher loss of body condition and elevated NEFA concentrations had higher P4 concentrations during estrus, a reduced estrous activity and insemination rate, but no depression in pregnancy per artificial insemination.

Relationship between moderate-to-vigorous physical activity, abdominal fat and immunometabolic markers in postmenopausal women

ObjectsTo assess the burden of levels of physical activity, non-esterified fatty acids (NEFA), triacylglycerol and abdominal fat on the immunometabolic profile of postmenopausal women. Study designForty-nine postmenopausal women [mean age 59.43 (standard deviation 5.61) years] who did not undertake regular physical exercise participated in this study. Body composition was assessed using dual-energy X-ray absorptiometry, and levels of NEFA, tumour necrosis factor-α, adiponectin, insulin and triacylglycerol were assessed using fasting blood samples. The level of physical activity was assessed using an accelerometer (Actigraph GTX3x), and reported as counts/min, time spent undertaking sedentary activities and time spent undertaking moderate-to-vigorous physical activity (MVPA). The following conditions were considered to be risk factors: (i) sedentary lifestyle (<150min of MVPA per week); (ii) high level (above median) of abdominal fat; and (iii) hypertriacylglycerolaemia (<150mg/dl of triacylglycerol). ResultsIn comparison with active women, sedentary women had higher levels of body fat (%) (p=0.041) and NEFA (p=0.064). Women with higher levels of abdominal fat had impaired insulin resistance (HOMA-IR) (p=0.016) and spent more time undertaking sedentary activities (p=0.043). Moreover, the women with two risk factors or more had high levels of NEFA and HOMA-IR (p<0.05), as well as an eight-fold higher risk of a high level of NEFA, independent of age (p<0.05). No significant relationship was found between levels of physical activity, abdominal fat, tumour necrosis factor-α and adiponectin (p>0.05). ConclusionPostmenopausal women with a combination of hypertriacylglycerolaemia, a high level of abdominal fat and a sedentary lifestyle are more likely to have metabolic disturbances.

The rs340874 PROX1 type 2 diabetes mellitus risk variant is associated with visceral fat accumulation and alterations in postprandial glucose and lipid metabolism.

Large-scale meta-analyses of genome-wide association studies have recently confirmed that the rs340874 single-nucleotide polymorphism in PROX1 gene is associated with fasting glycemia and type 2 diabetes mellitus; however, the mechanism of this link was not well established. The aim of our study was to evaluate the functional/phenotypic differences related to rs340874 PROX1 variants. The study group comprised 945 subjects of Polish origin (including 634 with BMI > 25) without previously known dysglycemia. We analyzed behavioral patterns (diet, physical activity), body fat distribution and glucose/fat metabolism after standardized meals and during the oral glucose tolerance test. We found that the carriers of the rs340874 PROX1 CC genotype had higher nonesterified fatty acids levels after high-fat meal (p = 0.035) and lower glucose oxidation (p = 0.014) after high-carbohydrate meal in comparison with subjects with other PROX1 genotypes. Moreover, in subjects with CC variant, we found higher accumulation of visceral fat (p < 0.02), but surprisingly lower daily food consumption (p < 0.001). We hypothesize that lipid metabolism alterations in subjects with the PROX1 CC genotype may be a primary cause of higher glucose levels after glucose load, since the fatty acids can inhibit insulin-stimulated glucose uptake by decreasing carbohydrate oxidation. Our observations suggest that the PROX1 variants have pleiotropic effect on disease pathways and it seem to be a very interesting goal of research on prevention of obesity and type 2 diabetes mellitus. The study may help to understand the mechanisms of visceral obesity and type 2 diabetes mellitus risk development.

Sasa borealis Extract Efficiently Enhanced Swimming Capacity by Improving Energy Metabolism and the Antioxidant Defense System in Mice.

This study was conducted to determine the effects of 50% ethanolic extract from Sasa borealis leaves (SBE) on swimming capacity and oxidative metabolism in mice. The mice were divided into 2 groups with similar swimming times and body weights; Ex-Control and Ex-SBE were orally administered with distilled water and 250 mg/kg body weight/d of SBE. Exhaustive swimming times were prolonged by 1.5-fold in the Ex-SBE group compared to the Ex-Control. The Ex-SBE group displayed lower lactate and higher non-esterified fatty acid levels 15 min after swimming and the hepatic and muscle glycogen levels were significantly higher than that in the Ex-Control. SBE potentially enhanced mRNA expression of citrate synthase (CS), carnitine palmitoyltransferase (CPT-1), and β-hydroxyacyl coenzyme A dehydrogenase (β-HAD) in skeletal muscle. The activities and mRNA expression of catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) were elevated in the Ex-SBE compared with the Ex-Control after exhaustive swimming. These results suggest that SBE might be used as an effective agent to enhance swimming capacity by utilization of energy substrates and might ameliorate physical exhaustion by facilitating energy-generating metabolic genes and enhancing endogenous antioxidants.

NEFAs activate the oxidative stress-mediated NF-κB signaling pathway to induce inflammatory response in calf hepatocytes

Non-esterified fatty acids (NEFAs) are important induction factors of inflammatory responses in some metabolic diseases. High plasma levels of NEFAs and oxidative stress exist in the dairy cows with ketosis. The aim of this study was to investigate whether high levels of NEFAs can induce inflammatory response and the specific molecular mechanism in the hepatocytes of dairy cow. In vitro, primary cultured bovine hepatocytes were treated with different concentrations of NEFAs, PDTC (an NF-κB inhibitor) and NAC (an antioxidant). NEFAs significantly activated NF-κB pathway. Activated NF-κB upregulated the release of pro-inflammatory cytokines, thereby inducing inflammatory response in bovine hepatocytes. When PDTC was added, activation of NF-κB-mediated inflammatory response induced by NEFAs was inhibited. NEFAs treatment results in the overproduction of the markers of oxidative stress, reactive oxygen species (ROS) and malondialdehyde (MDA), which were ameliorated by NAC treatment. These increased ROS and MDA were caused by decreasing activity of antioxidant system, including glutathione peroxidase, superoxide dismutase and catalase, in bovine hepatocytes treated with NEFAs. NAC also ameliorated NEFAs-mediated NF-κB activation and the release of pro-inflammatory cytokines. These results indicate that high concentrations of NEFAs can induce cattle hepatocytes inflammatory response through activating the oxidative stress-mediated NF-κB signaling pathway.