RESUMEN
The current study was conducted to examine the effect of l-carnitine (LC) supplementation on telomere length and mitochondrial DNA copy number (mtDNAcn) per cell in mid-lactation cows challenged by lipopolysaccharide (LPS) in blood and liver. The mRNA abundance of 31 genes related to inflammation, oxidative stress, and the corresponding stress response mechanisms, the mitochondrial quality control and the protein import system, as well as the phosphatidylinositol 3-kinase/protein kinase B pathway, were assessed using microfluidics integrated fluidic circuit chips (96.96 dynamic arrays). In addition to comparing the responses in cows with or without LC, our objectives were to characterize the oxidative and inflammatory status by assessing the circulating concentration of lactoferrin (Lf), haptoglobin (Hp), fibrinogen, derivates of reactive oxygen metabolites (dROM), and arylesterase activity (AEA), and to extend the measurement of Lf and Hp to milk. Pluriparous Holstein cows were assigned to either a control group (CON, n = 26) or an LC-supplemented group (CAR; 25 g LC/cow per day; d 42 ante partum to d 126 postpartum (PP), n = 27). On d 111 PP, each cow was injected intravenously with LPS (Escherichia coli O111:B4, 0.5 µg/kg). The mRNA abundance was examined in liver biopsies of d -11 and +1 relative to LPS administration. Plasma and milk samples were frequently collected before and after the challenge. After LPS administration, circulating plasma fibrinogen and serum dROM concentrations increased, whereas AEA decreased. Moreover, serum P4 initially increased by 3 h after LPS administration and declined thereafter irrespective of grouping. The Lf concentrations increased in both groups after LPS administration, with the CAR group showing greater concentrations in serum and milk than the CON group. After LPS administration, telomere length in blood increased, whereas mtDNAcn per cell decreased; however, both remained unaffected in liver. For mitochondrial protein import genes, the hepatic mRNA abundance of the translocase of the mitochondrial inner membrane (TIM)-17B was increased in CAR cows. Moreover, TIM23 increased in both groups after LPS administration. Regarding the mRNA abundance of genes related to stress response mechanisms, 7 out of 14 genes showed group × time interactions, indicating a (local) protective effect due to the dietary LC supplementation against oxidative stress in mid-lactating dairy cows. For mtDNAcn and telomere length, the effects of the LPS-induced inflammation were more pronounced than the dietary supplementation of LC. Dietary LC supplementation affected the response to LPS primarily by altering mitochondrial dynamics. Regarding mRNA abundance of genes related to the mitochondrial protein import system, the inner mitochondrial membrane translocase (TIM complex) seemed to be more sensitive to dietary LC than the outer mitochondrial membrane translocase (TOM complex).
Asunto(s)
Enfermedades de los Bovinos , Lactancia , Femenino , Bovinos , Animales , Lactancia/fisiología , Lipopolisacáridos/efectos adversos , Carnitina/metabolismo , ADN Mitocondrial , Variaciones en el Número de Copia de ADN , Dinámicas Mitocondriales , Inflamación/veterinaria , Suplementos Dietéticos , Hígado/metabolismo , Leche/metabolismo , Dieta/veterinaria , Expresión Génica , Fibrinógeno/efectos adversos , Fibrinógeno/metabolismo , ARN Mensajero/metabolismo , Proteínas Mitocondriales/metabolismo , Telómero , Enfermedades de los Bovinos/metabolismoRESUMEN
Telomeres cap the ends of eukaryotic chromosomes, and the telomere length (TL) is related to cellular age. The mitochondrial DNA copy number (mtDNAcn) reflects the abundance of mitochondria in a cell. In addition to generating energy, mitochondria are also the main producers of reactive oxygen species, which in turn can accelerate TL attrition and impair mitochondrial function. Nutrition in early life could influence mtDNAcn and TL in later life. In the present study, we investigated the effects of feeding different levels of milk replacer (MR) on TL shortening and energetic status by examining mtDNAcn of heifers during their first year of life. In this study, whole blood samples were obtained from German Holstein heifer calves 36 to 48 h after birth (wk 1) and at wk 12 and wk 16 of life (n = 37), as well as from 31 calves when reaching 1 yr of age. Calves were fed either a high level of MR (14% solids) at 10 L/d (1.4 kg of MR/d; n = 18) or a restrictive low level at 5.7 L/d (0.8 kg of MR/d; n = 19) until linear weaning in wk 13 to 14 of life. Additional whole blood samples were taken from their respective dams 36 to 48 h after calving. Relative TL (qT) and mtDNAcn in cells from whole blood were measured by multiplex quantitative PCR. The greatest qT values were observed in neonates (36-48 h after birth), with decreasing qT values thereafter. Delta qT values were calculated as ΔqT = qT (first year of life) - initial qT (36-48 h after birth). We found no effect of the feeding regimen on qT values, but qT decreased with age. The mtDNAcn was lowest in neonates, increased until wk 12 of life, and then remained at a constant level until after weaning (wk 16). After the first year of life, mtDNAcn was decreased and returned to levels comparable to those of the neonatal stage. No differences in mtDNAcn were detectable between feeding groups within each time point. When comparing the values of qT and mtDNAcn between the calves and their dams after calving (36-48 h after birth and after calving), greater values were observed in calves than in dams. Delta qT values were negative in all but 2 calves (on the restricted diet), indicating that the change in TL with age was not uniform among individual animals, whereas no difference in mean ΔqT values occurred between the feeding groups. Additional analyses of the correlation between qT, mtDNAcn, and various indicators of oxidative status from birth until wk 16 of life did not indicate major interactions between oxidative status, qT and mtDNAcn. The results of this study support an age-dependent decrease of TL in calves independent of the MR feeding level and show the dynamic changes of mtDNAcn in early life.
Asunto(s)
Alimentación Animal , Dieta , Alimentación Animal/análisis , Animales , Bovinos , Variaciones en el Número de Copia de ADN , ADN Mitocondrial , Dieta/veterinaria , Femenino , Leche/metabolismo , Mitocondrias , Especies Reactivas de Oxígeno/metabolismo , Telómero , DesteteRESUMEN
Recent advances in neurobiology have emphasized the study of brain structure and function and its association with numerous pathological and toxicological events. Neurotransmitters are substances that relay, amplify, and modulate electrical signals between neurons and other cells. Neurotransmitter signaling mediates rapid intercellular communication by interacting with cell surface receptors, activating second messenger systems and regulating the activity of ion channels. Changes in the functional balance of neurotransmitters have been implicated in the failure of central nervous system function. In addition, abnormalities in neurotransmitter production or functioning can be induced by several toxicological compounds, many of which are found in the environment. The zebrafish has been increasingly used as an animal model for biomedical research, primarily due to its genetic tractability and ease of maintenance. These features make this species a versatile tool for pre-clinical drug discovery and toxicological investigations. Here, we present a review regarding the role of different excitatory and inhibitory neurotransmitter systems in zebrafish, such as dopaminergic, serotoninergic, cholinergic, purinergic, histaminergic, nitrergic, glutamatergic, glycinergic, and GABAergic systems, and emphasizing their features as pharmacological and toxicological targets. The increase in the global knowledge of neurotransmitter systems in zebrafish and the elucidation of their pharmacological and toxicological aspects may lead to new strategies and appropriate research priorities to offer insights for biomedical and environmental research.
Asunto(s)
Sistema Nervioso Central/efectos de los fármacos , Modelos Animales , Neurotransmisores/metabolismo , Farmacología/métodos , Toxicología/métodos , Pez Cebra/metabolismo , Animales , Conducta Animal/efectos de los fármacos , Sistema Nervioso Central/metabolismo , Transmisión Sináptica/efectos de los fármacosRESUMEN
Object of this investigation was to evaluate attitudes and opinions of general practitioners, internal specialists and pharmacists with regard to vaccination. At the same time we investigated the actual vaccination state of these groups and of the medical staff and pharmacy staff. Physicians and pharmacists answered by using a four-page written questionnaire. The vaccination state was evaluated by a single-page questionnaire. Analyses were made by using the statistical program SPSS. The 161 physicians and 188 pharmacists participating in this study generally agree that the risk of infection in practice and pharmacy is not significant. The best vaccine protection in these groups was observed for tetanus. An effective inoculation against this pathogen was documented by 79.4% of physicians and 63.3% of pharmacists. 73.4% of physicians had also a protection against hepatitis B. All other vaccinations were documented as actually protective only in 6-55% of the cases. Physicians and pharmacists agree that their staff should have a vaccination against tetanus, diphtheria and poliomyelitis, followed by hepatitis B and influenza. The vaccination state of medical staff and pharmacy-staff does not attain the demanded standard. It shows levels of 3-70%. Further education in vaccination is more often practised by pharmacists and their staff than by physicians and medical staff. Physicians are more active in advising patients about vaccination than pharmacists and patients rather consult their doctor than a pharmacist to give them vaccination advice. There is still a need for motivation of physicians and pharmacists to be an example for their patients and clients respectively. In addition, more of public information could be helpful.