Genetic diversity and phylogenetic relationship of Angus herds in Hungary and analyses of their production traits.

OBJECTIVE: This study aims to investigate the genetic structure and characteristics of the Angus cattle population in Hungary. The survey was performed with the assistance of the Hungarian Hereford, Angus, Galloway Association (HHAGA). METHODS: Genetic parameters of 1,369 animals from 16 Angus herds were analyzed using the genotyping results of 12 microsatellite markers with the aid of PowerMarker, Genalex, GDA-NT2021, and STRUCTURE software. Genotyping of DNA was performed using an automated genetic analyzer. Based on pairwise identity by state values of animals, the Python networkx 2.3 library was used for network analysis of the breed and to identify the central animals. RESULTS: The observed numbers of alleles on the 12 loci under investigation ranged from 11 to 18. The average effective number of alleles was 3.201. The overall expected heterozygosity was 0.659 and the observed heterozygosity was 0.710. Four groups were detected among the 16 Angus herds. The breeders' information validated the grouping results and facilitated the comparison of birth weight, age at first calving, number of calves born and productive lifespan data between the four groups, revealing significant differences. We identified the central animals/herd of the Angus population in Hungary. The match of our group descriptions with the phenotypic data provided by the breeders further underscores the value of cooperation between breeders and researchers. CONCLUSION: The observation that significant differences in the measured traits occurred among the identified groups paves the way to further enhancement of breeding efficiency. Our findings have the potential to aid the development of new breeding strategies and help breeders keep the Angus populations in Hungary under genetic supervision. Based on our results the efficient use of an upcoming genomic selection can, in some cases, significantly improve birth weight, age at first calving, number of calves born and the productive lifespan of animals.

Population genetic features of calving interval of the Limousin beef cattle breed in Hungary.

Variance, covariance components, heritability, breeding values (BV) and genetic trends in calving interval (CI) of the Limousin population in Hungary were evaluated. A total of 3,008 CI data of 779 cows from three herds in 1996-2016 were processed. For influencing effects GLM method, for population genetic parameters and BV estimation BLUP animal model, for trend analyses linear regression was applied. The average CI obtained was 378.8 ± 3.1 days. The variance distribution components of the phenotype were as follow: age of cow at calving 34.30%, season of calving 26.09%, year of calving 23.00%, sire 7.45%, herd 3.23%, sex of calf 0.33% and type of calving 0.30%. The heritability of CI proved to be low (h2 d = 0.04 ± 0.02 and 0.03 ± 0.02; h2 m = 0.01 ± 0.02). The repeatability was low (R = 0.03 ± 0.02). Based on the phenotypic trend calculation, the CI of cows decreased by an average of 0.60 days per year (R 2 = 0.19; P < 0.05). In case of genetic trend calculation, the average BV of sires in CI increased 0.07 and 0.17 days per year (R 2 = 0.23 and 0.27; P < 0.05).

Poly(ADP-ribose) polymerase-1 depletion enhances the severity of inflammation in an imiquimod-induced model of psoriasis.

Poly(ADP-ribose) polymerase-1 (PARP1) is a pro-inflammatory protein, whose pro-inflammatory properties were demonstrated in human. The pro-inflammatory properties of PARP1 were shown in Th1- and Th2-mediated inflammatory pathologies, but not Th17-mediated inflammation. Thus, we studied the role of PARP1 in the imiquimod-induced model of psoriasis. To our surprise, in imiquimod-induced psoriasis, PARP1 acted as an anti-inflammatory factor and its genetic deletion exacerbated symptoms. We showed that in the absence of PARP1, the epidermis thickened and the number of TUNEL-positive cells decreased in the epidermis. These data indicate programmed cell death is decreased in keratinocytes. Changes in involucrin expression suggest that keratinocyte differentiation is hampered. Furthermore, epidermal expression of IL6 increased in the psoriasiform lesions of PARP1 knockout mice, suggesting that the inflammatory response is also derailed in the absence of PARP1. Finally, we showed that PARP1 expression is reduced in human psoriatic lesions compared with control skin samples. In imiquimod-treated HPV-KER keratinocytes, PARP inhibition recapitulated the in vivo findings, namely keratinocyte hyperproliferation; furthermore, the mRNA expression of psoriasis-associated cytokines (IL6, IL1ß, IL8, IL17 and IL23A) was also induced. The inhibition of TRPV1 abrogated the effects of the combined imiquimod + PARP inhibitor treatment.

Poly(ADP-ribose) polymerase-2 is a lipid-modulated modulator of muscular lipid homeostasis.

There is a growing body of evidence that poly(ADP-ribose) polymerase-2 (PARP2), although originally described as a DNA repair protein, has a widespread role as a metabolic regulator. We show that the ablation of PARP2 induced characteristic changes in the lipidome. The silencing of PARP2 induced the expression of sterol regulatory element-binding protein-1 and -2 and initiated de novo cholesterol biosynthesis in skeletal muscle. Increased muscular cholesterol was shunted to muscular biosynthesis of dihydrotestosterone, an anabolic steroid. Thus, skeletal muscle fibers in PARP2-/- mice were stronger compared to those of their wild-type littermates. In addition, we detected changes in the dynamics of the cell membrane, suggesting that lipidome changes also affect the biophysical characteristics of the cell membrane. In in silico and wet chemistry studies, we identified lipid species that can decrease the expression of PARP2 and potentially phenocopy the genetic abruption of PARP2, including artificial steroids. In view of these observations, we propose a new role for PARP2 as a lipid-modulated regulator of lipid metabolism.

Lithocholic acid, a bacterial metabolite reduces breast cancer cell proliferation and aggressiveness.

Our study aimed at finding a mechanistic relationship between the gut microbiome and breast cancer. Breast cancer cells are not in direct contact with these microbes, but disease could be influenced by bacterial metabolites including secondary bile acids that are exclusively synthesized by the microbiome and known to enter the human circulation. In murine and bench experiments, a secondary bile acid, lithocholic acid (LCA) in concentrations corresponding to its tissue reference concentrations (< 1 µM), reduced cancer cell proliferation (by 10-20%) and VEGF production (by 37%), aggressiveness and metastatic potential of primary tumors through inducing mesenchymal-to-epithelial transition, increased antitumor immune response, OXPHOS and the TCA cycle. Part of these effects was due to activation of TGR5 by LCA. Early stage breast cancer patients, versus control women, had reduced serum LCA levels, reduced chenodeoxycholic acid to LCA ratio, and reduced abundance of the baiH (7α/ß-hydroxysteroid dehydroxylase, the key enzyme in LCA generation) gene in fecal DNA, all suggesting reduced microbial generation of LCA in early breast cancer.

PARP10 (ARTD10) modulates mitochondrial function.

Poly(ADP-ribose) polymerase (PARP)10 is a PARP family member that performs mono-ADP-ribosylation of target proteins. Recent studies have linked PARP10 to metabolic processes and metabolic regulators that prompted us to assess whether PARP10 influences mitochondrial oxidative metabolism. The depletion of PARP10 by specific shRNAs increased mitochondrial oxidative capacity in cellular models of breast, cervical, colorectal and exocrine pancreas cancer. Upon silencing of PARP10, mitochondrial superoxide production decreased in line with increased expression of antioxidant genes pointing out lower oxidative stress upon PARP10 silencing. Improved mitochondrial oxidative capacity coincided with increased AMPK activation. The silencing of PARP10 in MCF7 and CaCo2 cells decreased the proliferation rate that correlated with increased expression of anti-Warburg enzymes (Foxo1, PGC-1α, IDH2 and fumarase). By analyzing an online database we showed that lower PARP10 expression increases survival in gastric cancer. Furthermore, PARP10 expression decreased upon fasting, a condition that is characterized by increases in mitochondrial biogenesis. Finally, lower PARP10 expression is associated with increased fatty acid oxidation.

Glycogen phosphorylase inhibition improves beta cell function.

BACKGROUND AND PURPOSE: Glycogen phosphorylase (GP) is the key enzyme for glycogen degradation. GP inhibitors (GPi-s) are glucose lowering agents that cause the accumulation of glucose in the liver as glycogen. Glycogen metabolism has implications in beta cell function. Glycogen degradation can maintain cellular glucose levels, which feeds into catabolism to maintain insulin secretion, and elevated glycogen degradation levels contribute to glucotoxicity. The purpose of this study was to assess whether influencing glycogen metabolism in beta cells by GPi-s affects the function of these cells. EXPERIMENTAL APPROACH: The effects of structurally different GPi-s were investigated on MIN6 insulinoma cells and in a mouse model of diabetes. KEY RESULTS: GPi treatment increased glycogen content and, consequently, the surface area of glycogen in MIN6 cells. Furthermore, GPi treatment induced insulin receptor ß (InsRß), Akt and p70S6K phosphorylation, as well as pancreatic and duodenal homeobox 1(PDX1) and insulin expression. In line with these findings, GPi-s enhanced non-stimulated and glucose-stimulated insulin secretion in MIN6 cells. The InsRß was shown to co-localize with glycogen particles as confirmed by in silico screening, where components of InsR signalling were identified as glycogen-bound proteins. GPi-s also activated the pathway of insulin secretion, indicated by enhanced glycolysis, mitochondrial oxidation and calcium signalling. Finally, GPi-s increased the size of islets of Langerhans and improved glucose-induced insulin release in mice. CONCLUSION AND IMPLICATIONS: These data suggest that GPi-s also target beta cells and can be repurposed as agents to preserve beta cell function or even ameliorate beta cell dysfunction in different forms of diabetes. LINKED ARTICLES: This article is part of a themed section on Inventing New Therapies Without Reinventing the Wheel: The Power of Drug Repurposing. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.2/issuetoc.

Metabolic roles of poly(ADP-ribose) polymerases.

Poly(ADP-ribosyl)ation (PARylation) is an evolutionarily conserved reaction that had been associated with numerous cellular processes such as DNA repair, protein turnover, inflammatory regulation, aging or metabolic regulation. The metabolic regulatory tasks of poly(ADP-ribose) polymerases (PARPs) are complex, it is based on the regulation of metabolic transcription factors (e.g. SIRT1, nuclear receptors, SREBPs) and certain cellular energy sensors. PARP over-activation can cause damage to mitochondrial terminal oxidation, while the inhibition of PARP-1 or PARP-2 can induce mitochondrial oxidation by enhancing the mitotropic tone of gene transcription and signal transduction. These PARP-mediated processes impact on higher order metabolic regulation that modulates lipid metabolism, circadian oscillations and insulin secretion and signaling. PARP-1, PARP-2 and PARP-7 are related to metabolic diseases such as diabetes, alcoholic and non-alcoholic fatty liver disease (AFLD, NAFLD), or on a broader perspective to Warburg metabolism in cancer or the metabolic diseases accompanying aging.

Deletion of PARP-2 induces hepatic cholesterol accumulation and decrease in HDL levels.

Poly(ADP-ribose) polymerase-2 (PARP-2) is acknowledged as a DNA repair enzyme. However, recent investigations have attributed unique roles to PARP-2 in metabolic regulation in the liver. We assessed changes in hepatic lipid homeostasis upon the deletion of PARP-2 and found that cholesterol levels were higher in PARP-2(-/-) mice as compared to wild-type littermates. To uncover the molecular background, we analyzed changes in steady-state mRNA levels upon the knockdown of PARP-2 in HepG2 cells and in murine liver that revealed higher expression of sterol-regulatory element binding protein (SREBP)-1 dependent genes. We demonstrated that PARP-2 is a suppressor of the SREBP1 promoter, and the suppression of the SREBP1 gene depends on the enzymatic activation of PARP-2. Consequently, the knockdown of PARP-2 enhances SREBP1 expression that in turn induces the genes driven by SREBP1 culminating in higher hepatic cholesterol content. We did not detect hypercholesterolemia, higher fecal cholesterol content or increase in serum LDL, although serum HDL levels decreased in the PARP-2(-/-) mice. In cells and mice where PARP-2 was deleted we observed decreased ABCA1 mRNA and protein expression that is probably linked to lower HDL levels. In our current study we show that PARP-2 impacts on hepatic and systemic cholesterol homeostasis. Furthermore, the depletion of PARP-2 leads to lower HDL levels which represent a risk factor to cardiovascular diseases.

Glycogen phosphorylase inhibitor N-(3,5-dimethyl-Benzoyl)-N'-(ß-D-glucopyranosyl)urea improves glucose tolerance under normoglycemic and diabetic conditions and rearranges hepatic metabolism.

Glycogen phosphorylase (GP) catalyzes the breakdown of glycogen and largely contributes to hepatic glucose production making GP inhibition an attractive target to modulate glucose levels in diabetes. Hereby we present the metabolic effects of a novel, potent, glucose-based GP inhibitor (KB228) tested in vitro and in vivo under normoglycemic and diabetic conditions. KB228 administration enhanced glucose sensitivity in chow-fed and obese, diabetic mice that was a result of higher hepatic glucose uptake. Besides improved glucose sensitivity, we have observed further unexpected metabolic rearrangements. KB228 administration increased oxygen consumption that was probably due to the overexpression of uncoupling protein-2 (UCP2) that was observed in animal and cellular models. Furthermore, KB228 treatment induced mammalian target of rapamycin complex 2 (mTORC2) in mice. Our data demonstrate that glucose based GP inhibitors are capable of reducing glucose levels in mice under normo and hyperglycemic conditions. Moreover, these GP inhibitors induce accommodation in addition to GP inhibition--such as enhanced mitochondrial oxidation and mTORC2 signaling--to cope with the glucose influx and increased glycogen deposition in the cells, however the molecular mechanism of accommodation is unexplored.