SARS-CoV-2 and mitochondrial health: implications of lifestyle and ageing

Infection with SARs-COV-2 displays increasing fatality with age and underlying co-morbidity, in particular, with markers of the metabolic syndrome and diabetes, which seems to be associated with a “cytokine storm” and an altered immune response. This suggests that a key contributory factor could be immunosenescence that is both age-related and lifestyle-induced. As the immune system itself is heavily reliant on mitochondrial function, then maintaining a healthy mitochondrial system may play a key role in resisting the virus, both directly, and indirectly by ensuring a good vaccine response. Furthermore, as viruses in general, and quite possibly this new virus, have also evolved to modulate immunometabolism and thus mitochondrial function to ensure their replication, this could further stress cellular bioenergetics. Unlike most sedentary modern humans, one of the natural hosts for the virus, the bat, has to “exercise” regularly to find food, which continually provides a powerful adaptive stimulus to maintain functional muscle and mitochondria. In effect, the bat is exposed to regular hormetic stimuli, which could provide clues on how to resist this virus. In this paper, we review the data that might support the idea that mitochondrial health, induced by a healthy lifestyle, could be a key factor in resisting the virus, and for those people who are perhaps not in optimal health, treatments that could support mitochondrial function might be pivotal to their long-term recovery

Cloning of a gene encoding an antigen associated with the centrosome in Drosophila

The monoclonal antibody Bx63 recognizes a centrosomal antigen of Drosophila melanogaster by indirect immunofluorescence and identifies two proteins, with apparent molecular weights of 185 x 10³ and 66 x 10³, on Western blots. We have used this antibody to isolate five clones (λcs1, -2, -3, -4 and λj63) from λgt11 expression libraries of Drosophila DNA. Using polyclonal anti-centrosomal sera raised against both immunoaffinity-purified Bx63 antigen and electrophoretically purified fusion protein from clone λcs3, we have demonstrated that the fusion proteins encoded by four of these clones (λcs1-4) share at least two epitopes with the 185 x 10³ M_r centrosomal antigen. This indicates that clones λcs1-4 contain DNA from the gene coding for this protein. The four clones are independent isolates from a single chromosomal site, which we show by in situ hybridization to correspond with salivary gland chromosome region 88E 4-8. A low-abundance transcript of approximately 4.0 x 10³ bases corresponding to the cloned gene is detected in all stages of the Drosophila life-cycle

Cloning of a gene encoding an antigen associated with the centrosome in Drosophila

The monoclonal antibody Bx63 recognizes a centrosomal antigen of Drosophila melanogaster by indirect immunofluorescence and identifies two proteins, with apparent molecular weights of 185 x 10³ and 66 x 10³, on Western blots. We have used this antibody to isolate five clones (λcs1, -2, -3, -4 and λj63) from λgt11 expression libraries of Drosophila DNA. Using polyclonal anti-centrosomal sera raised against both immunoaffinity-purified Bx63 antigen and electrophoretically purified fusion protein from clone λcs3, we have demonstrated that the fusion proteins encoded by four of these clones (λcs1-4) share at least two epitopes with the 185 x 10³ M_r centrosomal antigen. This indicates that clones λcs1-4 contain DNA from the gene coding for this protein. The four clones are independent isolates from a single chromosomal site, which we show by in situ hybridization to correspond with salivary gland chromosome region 88E 4-8. A low-abundance transcript of approximately 4.0 x 10³ bases corresponding to the cloned gene is detected in all stages of the Drosophila life-cycle

A technique for the determination of protein concentration by neutron activation analysis of silver binding

A method for the quantitative determination of small amounts of protein samples was developed employing neutron activation analysis. Current methods of protein concentration determination are severely limited as a result of differences in the specific characteristics of each protein. Silver binding has been used as a sensitive colorimetric method to indicate the presence of protein. However, silver-protein complexes can have a variety of absorbance spectra unique to each protein, which complicate the analysis. Various amounts of specific proteins were equilibrated in an excess of silver nitrate prior to the reduction of the silver by the addition of NaBH 4 , HCHO, and NaOH. The protein-silver complex was rapidly separated from the unbound silver by centrifugation chromatography and the amount of bound silver was determined by INAA. The amount of silver was proportional to the amount of protein present in each sample. When the silver was not reduced prior to removal of the unbound silver by chromatography, only negligible amounts of silver remained bound to the protein. The stoichiometry of bound silver to protein on a molar basis showed relatively small differences for the proteins that were examined. This ratio was found to depend on the conditions of the binding and reduction of the silver. The results suggest that the binding of silver is not specific to any charged or polar groups on these proteins and may, therefore, provide a means of determination of the concentration of protein that has general application for all proteins.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43109/1/10967_2005_Article_BF02037279.pd

α7 Nicotinic Acetylcholine Receptor Signaling Modulates Ovine Fetal Brain Astrocytes Transcriptome in Response to Endotoxin

Neuroinflammation in utero may result in lifelong neurological disabilities. Astrocytes play a pivotal role in this process, but the mechanisms are poorly understood. No early postnatal treatment strategies exist to enhance neuroprotective potential of astrocytes. We hypothesized that agonism on α7 nicotinic acetylcholine receptor (α7nAChR) in fetal astrocytes will augment their neuroprotective transcriptome profile, while the inhibition of α7nAChR will achieve the opposite. Using an in vivo–in vitro model of developmental programming of neuroinflammation induced by lipopolysaccharide (LPS), we validated this hypothesis in primary fetal sheep astrocytes cultures re-exposed to LPS in the presence of a selective α7nAChR agonist or antagonist. Our RNAseq findings show that a pro-inflammatory astrocyte transcriptome phenotype acquired in vitro by LPS stimulation is reversed with α7nAChR agonistic stimulation. Conversely, α7nAChR inhibition potentiates the pro-inflammatory astrocytic transcriptome phenotype. Furthermore, we conducted a secondary transcriptome analysis against the identical α7nAChR experiments in fetal sheep primary microglia cultures. Similar to findings in fetal microglia, in fetal astrocytes we observed a memory effect of in vivo exposure to inflammation, expressed in a perturbation of the iron homeostasis signaling pathway (hemoxygenase 1, HMOX1), which persisted under pre-treatment with α7nAChR antagonist but was reversed with α7nAChR agonist. For both glia cell types, common pathways activated due to LPS included neuroinflammation signaling and NF-κB signaling in some, but not all comparisons. However, overall, the overlap on the level of signaling pathways was rather minimal. Astrocytes, not microglia—the primary immune cells of the brain, were characterized by unique inhibition patterns of STAT3 pathway due to agonistic stimulation of α7nAChR prior to LPS exposure. Lastly, we discuss the implications of our findings for fetal and postnatal brain development

Maternal–fetal stress and DNA methylation signatures in neonatal saliva: an epigenome-wide association study

Background: Maternal stress before, during and after pregnancy has profound effects on the development and lifelong function of the infant’s neurocognitive development. We hypothesized that the programming of the central nervous system (CNS), hypothalamic–pituitary–adrenal (HPA) axis and autonomic nervous system (ANS) induced by prenatal stress (PS) is reflected in electrophysiological and epigenetic biomarkers. In this study, we aimed to find noninvasive epigenetic biomarkers of PS in the newborn salivary DNA. Results: A total of 728 pregnant women were screened for stress exposure using Cohen Perceived Stress Scale (PSS), 164 women were enrolled, and 114 dyads were analyzed. Prenatal Distress Questionnaire (PDQ) was also administered to assess specific pregnancy worries. Transabdominal fetal electrocardiograms (taECG) were recorded to derive coupling between maternal and fetal heart rates resulting in a ‘Fetal Stress Index’ (FSI). Upon delivery, we collected maternal hair strands for cortisol measurements and newborn’s saliva for epigenetic analyses. DNA was extracted from saliva samples, and DNA methylation was measured using EPIC BeadChip array (850 k CpG sites). Linear regression was used to identify associations between PSS/PDQ/FSI/Cortisol and DNA methylation. We found epigenome-wide significant associations for 5 CpG with PDQ and cortisol at FDR < 5%. Three CpGs were annotated to genes (Illumina Gene annotation file): YAP1, TOMM20 and CSMD1, and two CpGs were located approximately lay at 50 kb from SSBP4 and SCAMP1. In addition, two differentiated methylation regions (DMR) related to maternal stress measures PDQ and cortisol were found: DAXX and ARL4D. Conclusions: Genes annotated to these CpGs were found to be involved in secretion and transportation, nuclear signaling, Hippo signaling pathways, apoptosis, intracellular trafficking and neuronal signaling. Moreover, some CpGs are annotated to genes related to autism, post-traumatic stress disorder (PTSD) and schizophrenia. However, our results should be viewed as hypothesis generating until replicated in a larger sample. Early assessment of such noninvasive PS biomarkers will allow timelier detection of babies at risk and a more effective allocation of resources for early intervention programs to improve child development. A biomarker-guided early intervention strategy is the first step in the prevention of future health problems, reducing their personal and societal impact.Fil: Sharma, Ritika. Technische Universitat München; AlemaniaFil: Frasch, Martin Gerbert. University of Washington; Estados UnidosFil: Zelgert, Camila. Technische Universitat München; AlemaniaFil: Zimmermann, Peter. Technische Universitat München; AlemaniaFil: Fabre, Bibiana. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Fisiopatología y Bioquímica Clínica; ArgentinaFil: Wilson, Rory. Helmholtz Zentrum Munich; AlemaniaFil: Waldenberger, Melanie. Helmholtz Zentrum Munich; AlemaniaFil: MacDonald, James W.. University of Washington; Estados UnidosFil: Bammler, Theo K.. University of Washington; Estados UnidosFil: Lobmaier, Silvia M.. Technische Universitat München; AlemaniaFil: Antonelli, Marta Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; Argentin

A Precise Bicoid Gradient Is Nonessential during Cycles 11–13 for Precise Patterning in the Drosophila Blastoderm

Background: During development, embryos decode maternal morphogen inputs into highly precise zygotic gene expression. The discovery of the morphogen Bicoid and its profound effect on developmental programming in the Drosophila embryo has been a cornerstone in understanding the decoding of maternal inputs. Bicoid has been described as a classical morphogen that forms a concentration gradient along the antero-posterior axis of the embryo by diffusion and initiates expression of target genes in a concentration-dependent manner in the syncytial blastoderm. Recent work has emphasized the stability of the Bicoid gradient as a function of egg length and the role of nuclear dynamics in maintaining the Bicoid gradient. Bicoid and nuclear dynamics were observed but not modulated under the ideal conditions used previously. Therefore, it has not been tested explicitly whether a temporally stable Bicoid gradient prior to cellularization is required for precise patterning. Principal Findings: Here, we modulate both nuclear dynamics and the Bicoid gradient using laminar flows of different temperature in a microfluidic device to determine if stability of the Bicoid gradient prior to cellularization is essential for precise patterning. Dramatic motion of both cytoplasm and nuclei was observed prior to cellularization, and the Bicoid gradient was disrupted by nuclear motion and was highly abnormal as a function of egg length. Despite an abnormal Bicoid gradient during cycles 11–13, Even-skipped patterning in these embryos remained precise. Conclusions: These results indicate that the stability of the Bicoid gradient as a function of egg length is nonessential during syncytial blastoderm stages. Further, presumably no gradient formed by simple diffusion on the scale of egg length could be responsible for the robust antero-posterior patterning observed, as severe cytoplasmic and nuclear motion would disrupt such a gradient. Additional mechanisms for how the embryo could sense its dimensions and interpret the Bicoid gradient are discussed

Smooth Muscle Myosin Inhibition: A Novel Therapeutic Approach for Pulmonary Hypertension

Pulmonary hypertension remains a major clinical problem despite current therapies. In this study, we examine for the first time a novel pharmacological target, smooth muscle myosin, and determine if the smooth muscle myosin inhibitor, CK-2019165 (CK-165) ameliorates pulmonary hypertension.Six domestic female pigs were surgically instrumented to measure pulmonary blood flow and systemic and pulmonary vascular dynamics. Pulmonary hypertension was induced by hypoxia, or infusion of the thromboxane analog (U-46619, 0.1 µg/kg/min, i.v.). In rats, chronic pulmonary hypertension was induced by monocrotaline.CK-165 (4 mg/kg, i.v.) reduced pulmonary vascular resistance by 22±3 and 28±6% from baseline in hypoxia and thromboxane pig models, respectively (p<0.01 and 0.01), while mean arterial pressure also fell and heart rate rose slightly. When CK-165 was delivered via inhalation in the hypoxia model, pulmonary vascular resistance fell by 17±6% (p<0.05) while mean arterial pressure and heart rate were unchanged. In the monocrotaline model of chronic pulmonary hypertension, inhaled CK-165 resulted in a similar (18.0±3.8%) reduction in right ventricular systolic pressure as compared with sildenafil (20.3±4.5%).Inhibition of smooth muscle myosin may be a novel therapeutic target for treatment of pulmonary hypertension

Improving pregnancy outcomes in humans through studies in sheep

Experimental studies that are relevant to human pregnancy rely on the selection of appropriate animal models as an important element in experimental design. Consideration of the strengths and weaknesses of any animal model of human disease is fundamental to effective and meaningful translation of preclinical research. Studies in sheep have made significant contributions to our understanding of the normal and abnormal development of the fetus. As a model of human pregnancy, studies in sheep have enabled scientists and clinicians to answer questions about the etiology and treatment of poor maternal, placental, and fetal health and to provide an evidence base for translation of interventions to the clinic. The aim of this review is to highlight the advances in perinatal human medicine that have been achieved following translation of research using the pregnant sheep and fetus

Perspectives on the Trypanosoma cruzi-host cell receptor interaction

Chagas disease is caused by the parasite Trypanosoma cruzi. The critical initial event is the interaction of the trypomastigote form of the parasite with host receptors. This review highlights recent observations concerning these interactions. Some of the key receptors considered are those for thromboxane, bradykinin, and for the nerve growth factor TrKA. Other important receptors such as galectin-3, thrombospondin, and laminin are also discussed. Investigation into the molecular biology and cell biology of host receptors for T. cruzi may provide novel therapeutic targets