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Biology subjects

Consiglio, A.

Publications and source records attributed to Consiglio, A..

4 recordsLinked to original sources

Lost in HELLS: disentangling the mystery of SALNR existence in senescence cellular models

Long non-coding RNAs (lncRNAs) have emerged as key regulators of cellular senescence by transcriptionally and post-transcriptionally modulating the expression of many important genes involved in senescence-associated pathways and processes. Among the different lncRNAs associated to senescence, Senescence Associated Long Non-coding RNA (SALNR) was found to be down-regulated in different cellular models of senescence. Since its release in 2015, SALNR has not been annotated in any database or public repository, and no other experimental data have been published. The SALNR sequence is located on the long arm of chromosome 10, at band 10q23.33, and it overlaps the 3 end of the HELLS gene. This investigation helped to unravel the mystery of the existence of SALNR by analyzing publicly available short- and long-read RNA sequencing data sets and RT-PCR analysis in human tissues and cell lines. Additionally, the expression of HELLS has been studied in cellular models of replicative senescence, both in silico and in vitro. Our findings, while strongly questioning the actual existence of SALNR as an independent transcript, support the expression of a predicted HELLS isoform entirely covering the SALNR genomic region. Furthermore, we observed a strong down-regulation of HELLS in senescent cells versus proliferating cells, supporting its role in the senescence and aging process. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=106 SRC="FIGDIR/small/526712v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@1178eb8org.highwire.dtl.DTLVardef@19ae822org.highwire.dtl.DTLVardef@fe1c49org.highwire.dtl.DTLVardef@f31ae1_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

Metrics of Coral Microfragment Viability

Coral reefs are being degraded at unprecedented rates and decisive intervention actions are urgently needed to help them. One such intervention in aid of reefs is coral cryopreservation. Although the cryopreservation of coral sperm and larvae has been achieved, preservation of coral fragments including both its tissue and skeleton, has not. The goal of this paper was to understand and assess the physiological stressors that might underlie coral fragment cryopreservation and the long-term consequences of these physiological exposures to continued growth. Therefore, we assessed small fragments ([~]0.5 x0.5 mm2) from the Hawaiian coral, Porites compressa, examining: 1) the sensitivity of the fragments and their algal symbionts to chilling temperatures; 2) the sensitivity of the coral to complex cryoprotectants; 3) methods to safely remove the algal symbionts from the coral fragment for cryopreservation, given the two symbiotic partners may require different cryopreservation protocols; 4) continued growth over time of coral fragments once returned to running seawater after treatment exposures; and, 5) assessment of health and viability of microfragments after treatments examining the distribution of green fluorescent protein and fluorescent symbionts. Technological advances in cryo-technology promise to support successful coral fragment cryopreservation soon, and its success could help secure much of the genetic and biodiversity of reefs in the next decade.

cell biology↗

Immunosuppressive tocilizumab prevents astrocyte induced neurotoxicity in hiPSC-LRRK2 Parkinson's disease by targeting receptor interleukin-6

Parkinsons disease (PD) is associated with premature death of dopamine-producing neurons in the brain. Previous studies have shown that astrocytes of PD patients may contribute to neuronal degeneration by mechanisms involving both direct cell-to-cell contact and transfer of soluble molecules. Since it has been proposed that PD patients exhibit an overall pro-inflammatory state, and since astrocytes are key mediators of the inflammation response in the brain, here we sought to address whether astrocyte-mediated inflammatory signaling could contribute to PD neuropathology. For this purpose, we generated astrocytes from induced pluripotent stem cells (iPSCs) representing PD patients and healthy controls. Transcriptomic analyses identified a unique inflammatory gene expression signature in PD astrocytes compared to controls. In particular, the pro-inflammatory cytokine IL-6 was found to be highly expressed and released by PD astrocytes, and to induce toxicity in dopamine neurons. Mechanistically, neuronal cell death was mediated by IL-6 signaling via IL-6 receptor (IL-6R) expressed in human PD neurons, leading to downstream activation of STAT3. Importantly, astrocyte-induced cell death in PD disease midbrain neurons could be prevented by blocking IL6R-mediated signaling using clinically available antibodies. Moreover, examination of postmortem tissue brain of early-stage PD patients uncovered increased numbers of dopamine neurons overexpressing IL-6R and of reactive astrocytes overexpressing IL-6, compared to healthy brains. Our findings highlight the potential role of astrocyte-mediated inflammatory signaling in neuronal loss in PD, and open the way for new therapies based on IL-6 immunomodulation for preventing PD pathogenesis.

neuroscience↗

iPSC-based modeling of THD recapitulates disease phenotypes and reveals neuronal malformation

Tyrosine hydroxylase deficiency (THD) is a rare genetic disorder leading to dopaminergic depletion and early-onset parkinsonism. Affected children present with either a severe form that does not respond to L-Dopa treatment (THD-B), or a milder L-Dopa responsive form (THD-A). We generated induced pluripotent stem cells (iPSCs) from THD patients that were differentiated into dopaminergic neurons (DAn) and compared with control-DAn from healthy individuals and gene-corrected isogenic controls. Consistent with patients, THD iPSC-DAn displayed lower levels of DA metabolites and reduced TH expression, when compared to controls. Moreover, THD iPSC-DAn showed abnormal morphology, including reduced total neurite length and either an abnormal TH proximodistal gradient (THDA), or neurite arborization defects (THDB). Treatment of THD-iPSC-DAn with L-Dopa rescued the neuronal defects and disease phenotype only in THDA-DAn. Interestingly, L-Dopa treatment at the stage of neuronal precursors could prevent the alterations in THDB-iPSC-DAn, thus suggesting the existence of a critical developmental window in THD. Our iPSC-based model recapitulates THD disease phenotypes and response to treatment, representing a promising tool for investigating pathogenic mechanisms, drug screening, and personalized management.

neuroscience↗