All RNA samples were immediately processed for cDNA preparation using SuperScript IV First\Strand Synthesis System (Invitrogen, 18091200). server https://www.openmicroscopy.org/omero/ and assigned the link: http://homeros.kennedy.ox.ac.uk/pub/chen\et\al\2020\3dEndocrine. Abstract Age\associated alterations of the hormone\secreting endocrine system cause organ dysfunction and disease states. However, the cell biology of endocrine tissue ageing remains poorly understood. Here, we perform comparative 3D imaging to understand age\related perturbations of the endothelial cell (EC) compartment in endocrine glands. Datasets of a wide range of markers highlight a decline in capillary and artery numbers, but not of perivascular cells in pancreas, testis and thyroid gland, with age in mice and humans. Further, angiogenesis and \cell expansion in the pancreas are coupled by a distinct age\dependent subset of ECs. While this EC subpopulation supports pancreatic cells, it declines during ageing concomitant with increased expression of the gap junction protein Gja1. EC\specific ablation of Gja1 restores \cell expansion in the aged pancreas. These results provide a proof of concept for understanding age\related vascular changes and imply that therapeutic targeting of blood vessels may restore aged endocrine tissue function. This comprehensive data atlas offers over >?1,000 multicolour volumes for exploration and research in endocrinology, ageing, Cav 2.2 blocker 1 matrix and vascular biology. and expression (normalized to and expression (normalized to alleles (transgenics. Following tamoxifen administration in the adult 16\week\old mice and analysis of loss of function led to decreases not only in CD31+ Emcnhi vessel density and ESM\1+ cell numbers (Figs?6F and EV2J) but also in \cell numbers and \cell proliferation (Fig?6G and H). Quantification of insulin production and islet mass showed a notable decrease in and expression (normalized to and expression (normalized to expression (normalized to and transcripts were significantly higher expressed in CD31+ Emcnhi ECs relative to CD31+ Emcnlo ECs (Fig?6I). We also analysed transcript levels of these factors in human pancreas samples. Young human pancreatic tissues with high CD31+ Emcnhi islet capillaries showed higher expression of and compared to aged pancreas (Fig?EV2K). Further, multiple of these growth factors are known to promote angiogenesis and are required to maintain blood vessels. The up\regulation of secreted factors by CD31+ Emcnhi ECs and their Cav 2.2 blocker 1 decline in ageing including the loss of islet VEGFA with ageing (Fig?5I) indicate that the observed decline in blood vessels in the surrounding exocrine tissue of pancreas is mediated by islet/endocrine tissue. Further assessment of the relationship between angiogenesis and \cell expansion demonstrated that EC proliferation within islets positively correlated with Cav 2.2 blocker 1 \cell proliferation (Fig?6J). These results showed that active angiogenesis and formation of CD31+ Emcnhi vessels but not the quiescent vessels promoted \cell expansion. Transcript analysis of factors involved in blood vessel growth and proliferation (Lu and transcripts in CD31+ Emcnhi subset (Fig?6K). In addition to growth factor signalling, cellular interactions between ECs drive angiogenic process (Carmeliet, 2003; Melgar\Lesmes & Edelman, 2015). Gene expression analysis showed an abundant increase in transcript levels of junctional proteins in islet ECs (Fig?6K). Notably, a gap junction protein Gja1, commonly known as Connexin 43, the most abundant isoform of gap junction protein on ECs, demonstrated a significant decrease in the CD31+ Emcnhi subset (Fig?6K). Interestingly, showed an age\dependent expression in the CD31+ Emcnhi EC subset with a significant increase from juvenile to adult and a Cav 2.2 blocker 1 further Rabbit Polyclonal to LSHR increase in aged pancreas (Fig?6L). Thus, the islet CD31+ Emcnhi capillary EC subset exhibited specific expression profiles suggesting its specific functional properties. Endothelial Gja1 negatively regulates CD31+ Emcnhi ESM\1+ ECs Gja1 belongs to the family of transmembrane proteins that assemble as hexameric plasma membrane structures connexons (Solan & Cav 2.2 blocker 1 Lampe, 2009). Connexons function either as plasma membrane channel, termed hemichannel, or dock head\to\head with another connexon from an adjacent cell self\assembling into a gap junction intercellular channel (Goodenough & Paul, 2009). To investigate the functional role of Gja1 in blood vessels of the endocrine system, inducible EC\specific loss\of\function mice (alleles and transgenics. Following tamoxifen administration in adult mice and analysis at 19\week\old mice, the knockout mice (alleles transgenic mice (Wang gene loss of function. Cre\negative transgenic mice. Cre\negative dimension was around 22.14C53.3?m at 0.82?m interval size. 20 Plan Apo/0.8 dry lens, 20 Plan Apo 1.0 DIC VIS\IR D0.17 water dipping lens and 10X Plan Apo 0.45 WD?=?2.0 M27 dry lens were used for tiling. Large regions through the sections of endocrine gland sections were imaged using tile scan function with appropriate numbers of tiles according to the specific size of each sample, and images were then stitched with 10% overlap using Zen Black (version 3.1, Zeiss) software. All instrument settings were kept at the same between acquisitions of young and aged samples for each gland or between littermate controls and mutants. Z\stacks of images were processed and.