Dilution of seawater affects the Ca2 + transport in the outer mantle epithelium of crassostrea gigas

Varying salinities of coastal waters are likely to affect the physiology and ion transport capabilities of calcifying marine organisms such as bivalves. To investigate the physiological effect of decreased environmental salinity in bivalves, adult oysters (Crassostrea gigas) were exposed for 14 days to 50% seawater (14) and the effects on mantle ion transport, electrophysiology and the expression of Ca2+ transporters and channels relative to animals maintained in full strength sea water (28) was evaluated. Exposure of oysters to a salinity of 14 decreased the active mantle transepithelial ion transport and specifically affected Ca2+ transfer. Gene expression of the Na+/K+-ATPase and the sarco(endo)plasmic reticulum Ca2+-ATPase was decreased whereas the expression of the T-type voltage-gated Ca channel and the Na+/Ca2+-exchanger increased compared to animals maintained in full SW. The results indicate that decreased environmental salinities will most likely affect not only osmoregulation but also bivalve biomineralization and shell formation.Funding Agency European Union (EU) 605051 Swedish Mariculture Research Center, SWEMARC, University of Gothenburg Herbert & Karin Jacobssons Stiftelse 15/h17 Helge Ax:son Johnsons Stiftelse F18-0128 Portuguese Foundation for Science and Technology UID/Multi/04326/2019 Portuguese Foundation for Science and Technology UID/Multi/04326/2019 FCT, under the "Norma Transitoria" DL57/2016/CP1361/CT0020 DL57/2016/CP1361/CT0011info:eu-repo/semantics/publishedVersio

Serum-Free Xenogen-Free Culture Conditions Support Human Explant-Derived Cardiac Stem Cell Growth

Autologous explant-derived cardiac stem cell (EDC) therapies are a promising therapy for ischemic cardiomyopathy, but straightforward clinical translation is limited by traditional culture conditions which are often supplemented with ill-defined and xenobiotic components such as fetal bovine serum. Therefore, we investigated the influence of a commercially sourced serum-free (SF) xenogen-free medium on human EDC yield, phenotype, in vitro measures of EDC performance, and post-infarct cardiac repair using an immunodeficient mouse model of acute myocardial infarction. Despite reduced production of several pro-cardiogenic cytokines, SF EDCs promoted similar vessel formation, circulating stem cell recruitment and cardiogenic differentiation as compared to standard cultures. Transplant of SF EDCs into immunodeficient mice 1 week after myocardial infarction boosted post-ischemic repair beyond that of standard EDCs by enhancing viable myocardium within the infarct. These findings demonstrate that serum-free culture methods provide a superior cardiac-derived cell product with ready clinical translatability

Cell-type Specific Distribution of Chloride Transporters in the Rat Suprachiasmatic Nucleus

The suprachiasmatic nucleus (SCN) is a circadian oscillator and biological clock. Cell-to-cell communication is important for synchronization among SCN neuronal oscillators and the great majority of SCN neurons use γ-aminobutyric acid (GABA) as a neurotransmitter, the principal inhibitory neurotransmitter in the adult central nervous system. Acting via the ionotropic GABAA receptor, a chloride ion channel, GABA typically evokes inhibitory responses in neurons via Cl− influx. Within the SCN GABA evokes both inhibitory and excitatory responses although the mechanism underlying GABA-evoked excitation in the SCN is unknown. GABA-evoked depolarization in immature neurons in several regions of the brain is a function of intracellular chloride concentration, regulated largely by the cation-chloride cotransporters NKCC1 (for chloride entry) and KCC1-4 (for chloride egress). It is well established that changes in the expression of the cation-chloride cotransporters through development determines the polarity of the response to GABA. To understand the mechanisms underlying GABA-evoked excitation in the SCN, we examined the SCN expression of cationchloride cotransporters. Previously we reported that the K+/ Cl− cotransporter KCC2, a neuron-specific chloride extruder conferring GABA\u27s more typical inhibitory effects, is expressed exclusively in vasoactive intestinal peptide (VIP) and gastrinreleasing peptide (GRP) neurons in the SCN. Here we report that the K+/Cl− cotransporter isoforms KCC4 and KCC3 are expressed solely in vasopressin (VP) neurons in the SCN whereas KCC1 is expressed in VIP neurons, similar to KCC2. NKCC1 is expressed in VIP, GRP and VP neurons in the SCN as is WNK3, a chloride-sensitive neuron-specific serine-threonine kinase which modulates intracellular chloride concentration via opposing actions on NKCC and KCC cotransporters. The heterogeneous distribution of cation-chloride cotransporters in the SCN suggests that Cl− levels are differentially regulated within VIP/GRP and VP neurons. We suggest that GABA\u27s excitatory action is more likely to be evoked in VP neurons that express KCC4

Isolation of human explant derived cardiac stem cells from cryopreserved heart tissue.

The value of preserving high quality bio specimens for fundamental research is significant as linking cellular and molecular changes to clinical and epidemiological data has fueled many recent advances in medicine. Unfortunately, storage of traditional biospecimens is limited to fixed samples or isolated genetic material. Here, we report the effect of cryopreservation of routine myocardial biopsies on explant derived cardiac stem cell (EDC) culture outcomes. We demonstrate that immediate cryopreservation or delayed cryopreservation after suspension within cardioplegia for 12 hours did not alter EDC yields, proliferative capacity, antigenic phenotype or paracrine signature. Cryopreservation had negligible effects on the ability of EDCs to adopt a cardiac lineage, stimulate new vessel growth, attract circulating angiogenic cells and repair injured myocardium. Finally, cryopreservation did not influence the ability of EDCs to undergo genetic reprogramming into inducible pluripotent stem cells. This study establishes a means of storing cardiac samples as a retrievable live cell source for cardiac repair or disease modeling

The impact of patient co-morbidities on the regenerative capacity of cardiac explant-derived stem cells

Abstract Background Although patient-sourced cardiac stem cells repair damaged myocardium, the extent to which medical co-morbidities influence cardiac-derived cell products is uncertain. Therefore, we investigated the influence of atherosclerotic risk factors on the regenerative performance of human cardiac explant-derived cells (EDCs). Methods In this study, the Long Term Stratification for survivors of acute coronary syndromes model was used to quantify the burden of cardiovascular risk factors within a group of patients with established atherosclerosis. EDCs were cultured from human atrial appendages and injected into immunodeficient mice 7 days post-left coronary ligation. Cytokine arrays and enzyme linked immunoassays were used to determine the release of cytokines by EDCs in vitro, and echocardiography was used to determine regenerative capabilities in vivo. Results EDCs sourced from patients with more cardiovascular risk factors demonstrated a negative correlation with production of pro-healing cytokines (such as stromal cell derived factor 1α) and exosomes which had negative effects on the promotion of angiogenesis and chemotaxis. Reductions in exosomes and pro-healing cytokines with accumulating medical co-morbidities were associated with increases in production of the pro-inflammatory cytokine interleukin-6 (IL-6) by EDCs. Increased patient co-morbidities were also correlated with significant attenuation in improvements of left ventricular ejection fraction. Conclusions The regenerative performance of the earliest precursor cell population cultured from human explant tissue declines with accumulating medical co-morbidities. This effect is associated with diminished production of pro-cardiogenic cytokines and exosomes while IL-6 is markedly increased. Predictors of cardiac events demonstrated a lower capacity to support angiogenesis and repair injured myocardium in a mouse model of myocardial infarction