Effect of different selenium sources and concentrations on glutathione peroxidase activity and cholesterol metabolism of beef cattle

Exploring precision-cut liver slices for comparative xenobiotic metabolism profiling in swine and cattle

In vitro systems are useful tools for unravelling species differences in xenobiotic metabolism.The current work aimed to validate the technique of precision-cut liver slices (PCLS) for comparative studies on xenobiotic metabolism in swine and cattle.PCLS from swine (n = 3) and cattle (n = 3) were produced using a Brendel-VitronTM Tissue Slicer and cultured for 6 h. Tissue viability was preserved throughout the whole culture period.Metabolic viability was evaluated using the anthelmintics albendazole (ABZ) and fenbendazole (FBZ) as model drugs, as well as other substrates of hepatic monooxygenases: benzydamine (BZ) N-oxygenase (FMO-dependent), and the O-dealkylations of 7-ethoxyresorufin (EROD, CYP1A1-dependent) and 7-methoxyresorufin (MROD, CYP1A2-dependent).ABZ S-oxygenation resulted 6-fold (cattle) and 13.6-fold (swine) higher (p = 0.001) compared to FBZ S-oxygenation.Similar BZ N-oxygenation and EROD activities were observed in PCLS cultures from both species. MROD was 2.5-fold higher (p = 0.033) in swine than in cattle. Similarly, ABZ S-oxygenation was 1.7-fold higher (p = 0.0002) in swine than in cattle. Conversely, a 82% higher (p = 0.0003) rate of FBZ S-oxygenation was evidenced in PCLS cultures from cattle compared to those from swine.Overall, this work shows that PCLS cultures are useful to obtain relevant information on species differences in xenobiotic metabolism.

An Overview of Reactive Oxygen Species Damage Occurring during In Vitro Bovine Oocyte and Embryo Development and the Efficacy of Antioxidant Use to Limit These Adverse Effects

The in vitro production (IVP) of bovine embryos has gained popularity worldwide and in recent years and its use for producing embryos from genetically elite heifers and cows has surpassed the use of conventional superovulation-based embryo production schemes. There are, however, several issues with the IVP of embryos that remain unresolved. One limitation of special concern is the low efficiency of the IVP of embryos. Exposure to reactive oxygen species (ROS) is one reason why the production of embryos with IVP is diminished. These highly reactive molecules are generated in small amounts through normal cellular metabolism, but their abundances increase in embryo culture because of oocyte and embryo exposure to temperature fluctuations, light exposure, pH changes, atmospheric oxygen tension, suboptimal culture media formulations, and cryopreservation. When uncontrolled, ROS produce detrimental effects on the structure and function of genomic and mitochondrial DNA, alter DNA methylation, increase lipid membrane damage, and modify protein activity. Several intrinsic enzymatic pathways control ROS abundance and damage, and antioxidants react with and reduce the reactive potential of ROS. This review will focus on exploring the efficiency of supplementing several of these antioxidant molecules on oocyte maturation, sperm viability, fertilization, and embryo culture.

Trace Minerals Supplementation with Great Impact on Beef Cattle Immunity and Health

Simple Summary

Supplementation with trace minerals (TM) is a husbandry strategy to improve cattle health. There is solid evidence of the beneficial effects of TM supplementation on the immune system. The concentration of TM in the soil is variable across the USA, with several regions having deficient levels in forages. Therefore, TM supplementation is highly recommended especially in areas where forages do not supply the mineral requirements. Before starting TM supplementation, it is important to evaluate the herd’s mineral profile, and the amount of TM the animals are consuming. Oral free-choice TM may not be sufficient to satisfy the requirements in certain situations, and could lead to TM deficiencies. This is due to a high variability in TM composition and intake, binding to undigested feed particles, reduced absorption, and antagonisms. Single, oral pulse-dose supplementation provides a controlled and homogeneous amount of TM intended to remove such a variation. However, this strategy does not efficiently increase circulating and hepatic TM levels. Parenteral TM supplementation has resulted in a more efficient increase in TM concentration. The strategic supplementation combining injectable TM during critical times of cattle management (e.g., vaccination) in conjunction with oral free-choice supplements has shown significant benefits for the immune response and protection against respiratory disease in beef cattle, reducing morbidity and treatment costs.

Abstract

Trace minerals (TM) play an important role in cattle immunity, health and performance. Although TM are needed in small quantities, they are fundamental for enzymes involved in antioxidant protection against cellular damage and several pathways of the immune response. Cattle TM status results from the balance between TM dietary intake and their requirements. Free-choice oral TM supplementation is a common practice in beef cattle production systems. However, there is a high variation in TM intake and thus TM status and bioavailability in animals receiving free-choice oral TM supplements. Strategic pulse-dose supplementation during critical points of beef cattle management provides a controlled amount of TM intended to remove such a variation. Adequate TM supplementation should not only satisfy the basal requirements but also provide a source of TM when there is a higher demand of the antioxidant systems or during the development of the immune response. This paper reviews the research-based evidence of the effects of TM supplementation on immunity and its impact on beef cattle health. This review highlights the benefits of a novel approach of strategic administration of injectable trace minerals (Se, Zn, Cu and Mn) during critical episodes of cattle management (e.g., around weaning or at vaccination) in combination with free-choice oral supplementation to maintain adequate TM and oxidative status, enhanced immunity and overall cattle health. This strategy has proven to decrease morbidity, which would positively impact the productivity of the beef cattle systems.

The Activity of Ten Natural Extracts Combined in a Unique Blend to Maintain Cholesterol Homeostasis-In Vitro Model

BACKGROUND

Hypercholesterolemia is a major cause of cardiovascular disease and statins, the HMGCoA inhibitors, are the most prescribed drugs. Statins reduce the production of hepatic cholesterol, leading to greater expression of the LDL receptor and greater absorption of circulating LDL, reducing peripheral LDL levels. Unfortunately, statins are believed to induce myopathy and other severe diseases. To overcome this problem, safe nutraceuticals with the same activity as statins could hold great promise in the prevention and treatment of hypercholesterolemia. In this study, the anti-cholesterol efficacy of a new nutraceutical, called Esterol10^®, was evaluated.

METHODS

HepG2 cells were used to study the biological mechanisms exerted by Esterol10^® analyzing different processes involved in cholesterol metabolism, also comparing data with Atorvastatin.

RESULTS

Our results indicate that Esterol10^® leads to a reduction in total hepatocyte cholesterol and an improvement in the biosynthesis of free cholesterol and bile acids. Furthermore, the anti-cholesterol activity of Esterol10^® was also confirmed by the modulation of the LDL receptor and by the accumulation of lipids, as well as by the main intracellular pathways involved in the metabolism of cholesterol.

CONCLUSIONS

Esterol10^® is safe and effective with anti-cholesterol activity, potentially providing an alternative therapy to those based on statins for hypercholesterolemia disease.