Monika Röntgen

Monika Röntgen
Leibniz Institute for Farm Animal Biology | FBN · Institute of Muscle Biology

PD Dr. med. vet. habil.

About

88
Publications
11,747
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1,907
Citations
Additional affiliations
July 2013 - present
Leibniz Institute for Farm Animal Biology
Position
  • Head od Growth & Development Unit
April 2004 - June 2013
Leibniz Institute for Farm Animal Biology
Position
  • Group Leader

Publications

Publications (88)
Article
Full-text available
Three-dimensional cell culture techniques mimic the in vivo cell environment more adequately than flat surfaces. Spheroids are multicellular aggregates and we aimed to produce scaffold-free spheroids of myogenic origin, called myospheres, using a mid-scale incubator and bioreactor hybrid. For the first time, we obtained spheroids from primary porci...
Article
Full-text available
Satellite cells (SATC), the most abundant skeletal muscle stem cells, play a main role in muscle plasticity, including the adaptive response following physical activity. Thus, we investigated how long-term phenotype selection of male mice for high running performance (Dummerstorf high Treadmill Performance; DUhTP) affects abundance, creatine kinase...
Article
Full-text available
The porcine congenital splay leg syndrome (PCS), even though being of transient nature, is still one of the most important causes for piglet losses due to its high incidence and mortality. Although, described decades ago, the pathogenetic mechanism is still elusive. Numerous, mostly descriptive studies characterized the syndrome at clinical, histol...
Article
Full-text available
Cardiomyocytes are among the most energy-intensive cell types. Interplay between the components of cellular magnesium (Mg) homeostasis and energy metabolism in cardiomyocytes is poorly understood. We have investigated the effects of dietary Mg content and presence/functionality of the Na⁺/Mg²⁺ exchanger SLC41A1 on enzymatic functions of selected co...
Article
Full-text available
The isolation and cultivation of intact, single myofibers presents a superior approach for studying myogenic cells in their native position. The cells' characteristics remain more similar to muscle tissue than in cell culture. Nevertheless, no routinely used method in higher vertebrates exists. Therefore, we aimed at establishing the isolation and...
Article
Full-text available
Low birth weight (LBW) can cause lifelong impairments in muscle development and growth. Satellite cells (SC) and their progeny are crucial contributors to myogenic processes. This study provides new data on LBW in piglets combining insights on energy metabolism, muscle capillarization and differences in SC presence and function. To this aim, muscle...
Article
This study aimed to identify interactions between state of lactation (dry or early lactating) and immune responder group (low, medium, or high) for energy metabolism traits as well as metabolic and immunological traits in dairy cows. In early lactation, when the energy priority of cows shifts toward the mammary gland, the energy available to be par...
Article
Our aim was to compare the energy balance estimated (EBest) according to equations published by various energy feeding systems (German Society for Nutrition Physiology, French National Institute for Agricultural Research, and National Research Council) and the EB calculated by use of calorimetrically measured heat production (EBhp) of 20 high-yield...
Article
Full-text available
The present study was conducted to assess the effects of the probiotic Enterococcus faecium AL41 (EF) and of the enteric pathogen Salmonella Enteritidis PT4 (SE) on the development of posthatch pectoralis major muscle (PM) of broiler chicks. The four experimental groups were control (CON), EF, SE, and EF+SE (EFSE). EF and SE were given per os from...
Article
This in vitro study examined the ability of important immune modulators [β-hydroxybutyrate (BHB), cortisol, prolactin, isoproterenol and insulin] to influence the responsiveness of peripheral blood mononuclear cells (PBMC) from multiparous dairy cows 29 ± 2 days before and 14 ± 3 days after calving. The activation and proliferation of PBMC in respo...
Article
Full-text available
Muscle stem cells, termed satellite cells (SC), and SC-derived myogenic progenitor cells (MPC) are involved in postnatal muscle growth, regeneration, and muscle adaptability. They can be released from their natural environment by mechanical disruption and tissue digestion. The literature contains several isolation protocols for porcine SC/MPC inclu...
Article
Full-text available
The proliferation of blood lymphocytes from nonpregnant, nonlactating heifers was comparable with that of nonpregnant cows in their first lactation. Both low and high levels of β-hydroxybutyrate and low levels of prolactin, but not isoproterenol, reduced the proliferative response of dairy heifers and cows in their first or second lactation.
Article
Full-text available
Background: Satellite cells (SC) and their descendants, muscle precursor cells (MPC), play a key role in postnatal muscle development, regeneration, and plasticity. Several studies have provided evidence that SC and MPC represent a heterogeneous population differing in their biochemical and functional properties. The identification and characteriz...
Article
Full-text available
Magnesium (Mg ²⁺ ) is an essential mineral without known specific regulatory mechanisms. In ruminants, plasma Mg ²⁺ concentration depends primarily on the balance between Mg ²⁺ absorption and Mg ²⁺ excretion. The primary site of Mg ²⁺ absorption is the rumen, where Mg ²⁺ is apically absorbed by both potential-dependent and potential-independent upt...
Article
Full-text available
The protective effect of polysaccharide glucan in chickens fed low doses of T-2 toxin was assessed. The binder effect of β-D-glucan on jejunal mucosa in relation to the expression of Na ⁺ /K ⁺ -ATPase, proliferative activity of enterocytes and number of goblet cells was investigated. A total of 40 one-day-old chickens were allocated to four groups:...
Article
Full-text available
The Na⁺/Mg²⁺ exchanger SLC41A1 (A1), a key component of intracellular Mg homeostasis (IMH), is the major cellular Mg²⁺ efflux system, and its overexpression decreases [Mg²⁺]intracellular. IMH plays an important role in the regulation of many cellular processes, including cellular signaling. However, whether the overexpression of A1 and the conseque...
Article
Full-text available
High performing dairy cows experience distinct metabolic stress during periods of negative energy balance. Subclinical disorders of the cow’s energy metabolism facilitate failure of adaptational responses resulting in health problems and reduced performance. The autonomic nervous system (ANS) with its sympathetic and parasympathetic branches plays...
Article
Full-text available
During postnatal development, hyperplastic and hypertrophic processes of skeletal muscle growth depend on the activation, proliferation, differentiation, and fusion of satellite cells (SC). Therefore, molecular and functional SC heterogeneity is an important component of muscle plasticity and will greatly affect long-term growth performance and mus...
Article
Free fatty acid receptors (FFAR) play significant roles in various physiological processes, including energy metabolism, through interaction with their ligands, fatty acids. To determine whether the receptors FFAR1 and FFAR2 are involved in the regulation of liver metabolism during the peripartal period, we selected 13 German Holstein multiparous d...
Article
The liver plays a central role in adaptation for energy requirements around calving, and changes in the effects of insulin on hepatic energy metabolism contribute to metabolic adaptation in dairy cows. Hepatic insulin effects may depend on body fat mobilization. The objective of this study was to investigate the effects of insulin on the hepatic ge...
Article
Dairy cows undergo significant metabolic and endocrine changes during the transition from pregnancy to lactation, and impaired insulin action influences nutrient partitioning toward the fetus and the mammary gland. Because impaired insulin action during transition is thought to be related to elevated body condition and body fat mobilization, we hyp...
Article
The aim of the present experiment was to compare silage prepared from maize having a brown midrib (BMR) mutation with control (CTR) maize to identify their effects on enteric methane emission, digesta mean retention time (MRT), ruminal fermentation and digestibility. In addition, the utility of archaeol present in faecal samples was validated as a...
Article
The solute carrier family 41 (SLC41) encompasses three members A1, A2, and A3. Based on their distant homology to the bacterial Mg(2+) channel MgtE, all have been linked to Mg(2+) transport. There is only very limited knowledge on the molecular biology and exact functions of SLC41A2 and SLC41A3. SLC41A1 is ubiquitously expressed and data on its fun...
Article
The solute carriers families 30 (SLC30; ZnT), 39 (SLC39; ZIP), and 31 (SLC31; CTR) are involved in the essential maintenance of cellular zinc (Zn(2+)) and copper (Cu(2+)) homeostasis, respectively. ZnTs mediate Zn(2+) extrusion from cells (SLC30A1) or transport Zn(2+) into organelles and secretory vesicles/granules (SLC30A2-SLC30A8). SLC39 family m...
Article
Full-text available
The 41st family of solute carriers (SLC41) comprises three members A1, A2, and A3, which are distantly homologous to bacterial Mg2+ channel MgtE. SLC41A1 was recently characterized as being an Na+/Mg2+ exchanger (NME; a predominant cellular Mg2+-efflux system). Little is known about the exact function of SLC41A2 and SLC41A3, although, these protein...
Article
Full-text available
Parkinson's disease (PD) is a complex multifactorial ailment predetermined by the interplay of various environmental and genetic factors. Systemic and intracellular magnesium (Mg) deficiency has long been suspected to contribute to the development and progress of PD and other neurodegenerative diseases. However, the molecular background is unknown....
Data
Confocal immunolocalization of HA-strep-SLC41A1 (wt) and HA-strep-SLC41A1-p.A350V in -tet (24 h) cells. Strep-tagged wt and p.A350V were immunolabeled with primary mouse anti-strep and secondary GAM Alexa-488 antibodies (green signal). Plasma membranes were fluorescently contrasted with wheat germ agglutinin (WGA) conjugated to Alexa-647 (red signa...
Article
Agouti-related protein (AgRP), produced by neurons located in the arcuate nucleus of the hypothalamus stimulates feed intake. During early lactation dairy cows increase their feed intake and additionally mobilize their fat reserves leading to increased plasma non-esterified fatty acid (NEFA) concentrations. Since cows with a higher extent of fat mo...
Article
The beginning of lactation requires huge metabolic adaptations to meet increased energy demands for milk production of dairy cows. One of the adaptations is the mobilization of body reserves mainly from adipose tissue as reflected by increased plasma nonesterified fatty acid (NEFA) concentrations. The capacity of the liver for complete oxidation of...
Article
Full-text available
The Na(+)/Mg(2+) exchanger SLC41A1 is involved in the pathophysiology of various disease conditions. It forms high-molecular-mass, possibly hetero-oligomeric protein complexes in transgenic HEK293 cells. Therefore, we attempted to identify binding partners of SLC41A1 by utilizing the split-ubiquitin modification of the yeast two-hybrid assay. As th...
Chapter
The peptide hormone ghrelin is produced in the ruminal and proximal duodenal wall with a small portion of ghrelin being post-translationally modified by fatty acids at Ser3. Both forms (desacyl and acyl ghrelin) are released into the blood stream and have been initially assigned a role in the control of feed intake. While acyl ghrelin increases fee...
Chapter
Insulin response in skeletal muscles is thought to be impaired in dairy cows during early lactation to favor nutrient supply, especially glucose, towards the mammary gland. However, the molecular mechanisms of insulin action on glucose metabolism in cows and in other ruminants are still not completely understood, particularly during early lactation...
Chapter
Catecholamines increase around parturition in dairy cows and the hepatic adrenergic system is involved in metabolic adaptation during early lactation, e. g., by stimulation of hepatic glucose production (glycogenolysis and gluconeogenesis) after parturition to cover glucose demands (McDowell, 1983; Nonogaki, 2000; Weber et al., 2013). Effects of ad...
Chapter
The mobilization of adipose tissue of dairy cows during early lactation is reflected by increased fatty acid (FA) plasma concentrations. The capacity of the liver for complete oxidation of non-esterified FA (NEFA) is limited leading to an increased formation of ketone bodies, re-esterification, and accumulation of triacylglycerides in the liver. Th...
Chapter
During the transition from late pregnancy to early lactation, high-yielding dairy cows mobilize large amounts of adipose tissue resulting in increased plasma concentrations of non-esterified fatty acids (NEFA). NEFA are mostly oxidized to CO2 whereas at excessive concentrations, NEFA are re-esterified to form triacylglycerides leading to the develo...
Chapter
In mammals, the time of pregnancy and lactation is highly energy demanding and shifts the priority of energy partitioning from the immune system and body reserves towards the conceptus and the mammary gland (Nelson et al., 2002). The resulting peripartal breakdown of (acquired) immunity has been determined most of all by diminished blood leukocyte...
Article
Magnesium is essential for a wide variety of biochemical reactions and physiological functions, but its regulatory mechanisms (both at the cellular and at the systemic level) are still poorly characterized. Not least among the reasons for this gap are the technical difficulties in sensing minor changes occurring over a high background concentration...
Article
In addition to plasma metabolites and hormones participating as humoral signals in the control of feed intake, oxidative metabolic processes in peripheral organs also generate signals to terminate feeding. Although the degree of oxidation over longer periods is relatively constant, recent work suggests that the periprandial pattern of fuel oxidatio...
Article
Full-text available
Ghrelin is a gastrointestinal peptide hormone which is present in blood mostly in a non-posttranslationally-modified form, with a minor proportion acylated at Ser3. Both ghrelin forms were initially assigned a role in the control of food intake but there is accumulating evidence for their involvement in fat allocation and utilization. We investigat...
Article
A general phenomenon in peripartum mammals is the breakdown of (acquired) immunity. The incidence of parasite load, disease and inflammation often rise during the specific energetically demanding time of pregnancy and lactation. In this period, blood leukocytes display decreased DNA synthesis in response to mitogens in vitro. Leukocyte activation,...
Article
The onset of milk production lets mammals experience an enormous energy and nutrient demand. To meet these requirements, high-yielding dairy cows mobilize body fat resulting in an augmented hepatic oxidative metabolism, which has been suggested to signal for depressing hunger after calving. To examine how the extent of fat mobilization influences h...
Article
Ruminal vacuolar H(+)-ATPase (vH(+)-ATPase) activity is regulated by metabolic signals. Thus, we tested if its localization, expression and activity were changed by different feeding. Young male sheep (n = 12) were either fed hay ad libitum (h) or hay ad libitum plus additional concentrate (h/c) for two weeks. The vH(+)-ATPase B subunit signal was...
Article
An energy-rich diet leads to enhanced ruminal Na(+) absorption, which is associated with elevated plasma insulin-like growth factor 1 (IGF-1) levels and an increased number of IGF-1 receptors in rumen papillae. This study examined the in vitro effect of IGF-1 on Na(+) transport across the rumen epithelium of hay-fed sheep, in which the IGF-1 concen...
Article
Full-text available
Magnesium (Mg(2+)), the second most abundant divalent intracellular cation, is involved in the vast majority of intracellular processes, including the synthesis of nucleic acids, proteins, and energy metabolism. The concentration of intracellular free Mg(2+) ([Mg(2+)](i)) in mammalian cells is therefore tightly regulated to its optimum, mainly by a...
Article
Full-text available
In this study the protein and mRNA expression of Monocarboxylate transporter 1 (MCT1) was evaluated in rumen epithelial cells (REC) obtained from sheep fed hay ad libitum (control, h diet, n=4) or a mixed hay/concentrate diet (h/c diet, n=4) for two weeks. REC were isolated via fractionated trypsination and three groups consisting of fractions 3 to...
Article
Full-text available
In this study we investigated rumen papillae morphology and the localization and expression of the Na + /K + -ATPase in eight sheep fed hay ad libitum (h) or hay ad libitum plus additional concentrate (h/c). Four sheep were provided with the ad libitum h-diet for the complete three-week experimental period. The second group of four sheep received t...
Article
Evidence arguing for the existence of genes encoding for proteins directly involved in the transport of Mg2+ through the cytoplasmic membrane have accumulated over the last few years. Gene ACDP2 (ancient conserved domain protein 2; old name CNNM2, cyclin M2) is one such gene. ACDP2 is a distant homologue of the bacterial gene corC, which is known t...
Article
Mammary epithelial cells (HC11) chronically adapted to grow in a low-magnesium (0.05 mM vs. 0.5 mM) or in a high-magnesium (40 mM) medium were used to investigate on the mechanisms of cell magnesium transport under conditions of non-physiological magnesium availability. Magnesium influx was higher in low-magnesium cells compared to control or high-...
Article
Full-text available
In this study, the effect of metabolic inhibition (MI) by glucose substitution with 2-deoxyglucose (2-DOG) and/or application of antimycin A on ovine rumen epithelial cells (REC) vacuolar-type H(+)-ATPase (vH(+)-ATPase) activity was investigated. Using fluorescent spectroscopy, basal pH(i) of REC was measured to be 7.3 +/- 0.1 in HCO(3) (-)-free, g...
Article
Full-text available
An extensive number of investigations on the energetic utilization efficiency of nutrients and feedstuffs by cattle were carried out in the former Oskar-Kellner-Institute (now the »Oskar Kellner« Research Unit of Nutritional Physiology at the Research Institute for the Biology of Farm Animals (FBN), Dummerstorf). The amounts of methane (CH4) that t...
Article
A protein of approximately 70-kDa was identified as a candidate Na+/Mg2+ exchanger in rumen epithelial cells (REC). Melastatin-related Transient Receptor Potential 7 (TRPM7) and Magnesium Transporter 1 (MagT1) transcripts and, from them, encoded proteins were also detected. The regulation of these Mg transport pathways by extracellular [Mg] changes...
Article
An open-circuit indirect calorimetry system consisting of 4 climate-controlled respiration chambers for cattle has been constructed and validated. The system allows for the continuous monitoring of O(2), CO(2), and CH(4) concentrations in chamber air, and the simultaneous determination of feed and water intake, overall physical activity, position c...
Article
Nine non-pregnant, lactating dairy cows were used to study plasma and urinary magnesium concentrations ([Mg]pl; [Mg]u), and the urinary fractional excretion of magnesium (FE(Mg)) before, during and after an 120 min intravenous magnesium (Mg) administration (2.5 mg/kg body weight). Animals received a total mixed ration, and Mg content of the diet wa...
Article
The present study was performed to show the molecular identity of functionally characterized Mg transport pathways in rumen epithelial cells (REC) and to investigate the effects of extracellular [Mg] changes on their expression and activity. By using RT- PCR, Western blot, flow cytometry and immunocytochemistry, TRPM7, MagT1 and a Na+/Mg2+ exchange...
Article
Full-text available
The molecular biology of mammalian magnesium transporters and their interrelations in cellular magnesium homeostasis are largely unknown. Recently, the mouse SLC41A1 protein was suggested to be a candidate magnesium transporter with channel-like properties when overexpressed in Xenopus laevis oocytes. Here, we demonstrate that human SLC41A1 overexp...
Conference Paper
Full-text available
Background: Despite extensive functional evidence for the existence of various regulated Mg2+ transport proteins, only two plasmalemal channels (TRPM6, TRPM7), and mitochondrial channel (Mrs2p) have been molecularly confirmed to be involved in Mg2+ transport in mammalian cells. The recent identification of putative Mg2+ transporter SLC41A1 therefor...
Article
In this study, we have studied the expression, localization, and functionality of vacuolar-type H(+)-ATPase (vH(+)-ATPase) and Na(+)/K(+)-ATPase in the bovine rumen epithelium. Compared with the intracellular pH (pH(i)) of control rumen epithelial cells (REC; 7.06 +/- 0.07), application of inhibitors selective for vH(+)-ATPase (foliomycin) and Na(+...
Article
Full-text available
In this study data originating from complete metabolic trials with cattle of both sexes, fed 337 rations at feed intake levels between one to three times maintenance energy requirement were used to regress the total CH4 emission to the level of DM intake and to the nutrient composition, respectively. A major component of the measured CH4 emission c...
Chapter
Magnesium plays a vital role as a cofactor for many enzymes, as a binding partner of nucleotides, and in stabilizing nucleic acids and membranes. It acts as a modulator of ion channels, and it affects many other cellular processes such as neuromuscular excitability, secretion of hormones, and it antagonizes the actions of Ca2+, to name a few effect...