Biology subjects

Yang Loureiro, Z.

Publications and source records attributed to Yang Loureiro, Z..

6 recordsLinked to original sources

bioRxiv2026

Single-Nuclear RNA Sequencing Reveals Regional Specialization and Cellular Interactions in Epicardial and Perivascular Adipose Tissue

Background: Adipose tissue surrounding the heart and vasculature plays critical roles in cardiovascular homeostasis and disease, yet the cellular and molecular milieu of these depots at single-cell resolution remains incompletely characterized. Understanding how regional adipocytes differ transcriptionally and communicate with neighboring cardiovascular cells is essential for developing targeted therapeutic strategies. Methods: We performed single-nucleus RNA sequencing (snRNA-seq) on human adipose tissue from four anatomically distinct depots: ascending aorta, left atrium, right coronary artery, and subcutaneous fat. We characterized cellular composition, adipocyte and progenitor heterogeneity, depot-specific transcriptional programs, and intercellular communication networks. We further examined signaling remodeling in disease contexts, including atrial fibrillation and aortic aneurysm. Results: We identified six transcriptionally distinct adipocyte subpopulations and six adipocyte stromal and progenitor cell (ASPC) subpopulations were shared across depots but showed marked differences in abundance and gene expression reflecting developmental imprinting, including HOX family genes and anterior-posterior patterning programs. Intercellular communication analysis revealed depot-specific ligand-receptor interactions, with EPHA signaling identified as selectively enriched in the left atrial adipose depot. Disease-state analyses demonstrated extensive change in cell-cell communication in atrial fibrillation and aortic aneurysm, with differential regulation of FN1, EGF, SLIT, NOTCH, and CD46 signaling pathways. Conclusions: Our study reveals that cardiac and vascular adipose depots harbor transcriptionally specialized adipocytes and progenitors with distinct intercellular communication programs that are remodeled in atrial fibrillation and aortic aneurysm.

physiology↗

bioRxiv2026

Rapid Remodeling of Human White Adipose Tissue Following Bariatric Surgery

Bariatric surgery induces profound weight loss and improvement of obesity-associated metabolic dysfunction. Recent studies have shown that adipose tissue undergoes remodeling after weight loss, characterized by a reduction in proinflammatory immune cells, increased vascularization, and a shift in the adipocyte transcriptome, but these studies focused on time points long after surgery. We performed single nucleus RNA-seq (snRNA-seq) in subcutaneous white adipose tissue (SAT) samples from subjects with obesity undergoing bariatric surgery, collected at baseline and at one, six, and twelve months after surgery. We identify profound remodeling of SAT within the first month after surgery, characterized by a surge in lipid-associated macrophages and sharp reductions in specific populations of adipocytes, adipose stromal and progenitor cells (ASPCs), and endothelial cells. Transcriptional profiles strongly suggest that some adipocytes undergo apoptosis soon after surgery, while new adipocytes are generated by de novo differentiation. Mechanistically, the data are consistent with a model whereby coordinated early loss of a hedgehog signaling axis between endothelial cells and an anti-adipogenic population of ASPCs known as adipose regulatory cells (Aregs; ASPCPTCH2) enables a transient burst of adipogenesis to occur. Interestingly, very few of these early features seen in human subjects are represented in a mouse model of surgical weight loss.

physiology↗

bioRxiv2025

Single-nuclear transcriptomics of lymphedema-associated adipose reveals a pro-lymphangiogenic stromal cell population

Chronic lymphedema is a progressive, disfiguring disease that results from dysfunction of the lymphatic vasculature, causing distal accumulation of interstitial fluid, localized development of tissue edema, and expansion of subcutaneous adipose tissue (SAT). As the molecular mechanisms governing SAT remodeling in this disease are unclear, we performed single-nucleus RNA sequencing on paired control and affected SAT biopsies from patients with unilateral lymphedema. Lymphedema samples were characterized by expansion of SAA+ adipocytes, pro-adipogenic stem cells, and proliferation of lymphatic capillaries. A GRIA1+ lymphedema-enriched stromal cell population expressing VEGFC, ADAMTS3, and CCBE1 was identified, suggesting an enhanced axis of communication between adipose stem and progenitor cells (ASPCs) and lymphatic endothelial cells. Furthermore, lymphedema ASPC-conditioned media promoted lymphatic endothelial tube elongation and proliferation in vitro. These findings indicate a critical role for ASPCs in regulating adipocyte differentiation and lymphatic vascular remodeling in lymphedema, and provide a valuable resource for better understanding this disease.

cell biology↗

bioRxiv2024

PPARγ activation by lipolysis-generated ligands is required for cAMP dependent UCP1 induction in human thermogenic adipocytes

ObjectiveThe uncoupling protein 1 (UCP1) is induced in brown or "beige" adipocytes through catecholamine-induced cAMP signaling, which activates diverse transcription factors. UCP1 expression can also be enhanced by PPAR{gamma} agonists such as rosiglitazone (Rsg). However, it is unclear whether this upregulation results from de-novo differentiation of beige adipocytes from progenitor cells, or from the induction of UCP1 in pre-existing adipocytes. To explore this, we employed human adipocytes differentiated from progenitor cells and examined their acute response to Rsg, to the adenylate-cyclase activator forskolin (Fsk), or to both simultaneously. MethodsAdipocytes generated from primary human progenitor cells were differentiated without exposure to PPAR{gamma} agonists, and treated for 3, 6 or 78 hours to Fsk, to Rsg, or to both simultaneously. Bulk RNASeq, RNAScope, RT-PCR, CRISPR-Cas9 mediated knockout, oxygen consumption and western blotting were used to assess cellular responses. ResultsUCP1 mRNA expression was induced within 3 hours of exposure to either Rsg or Fsk, indicating that Rsgs effect is independent on additional adipocyte differentiation. Although Rsg and Fsk induced distinct overall transcriptional responses, both induced genes associated with calcium metabolism, lipid droplet assembly, and mitochondrial remodeling, denoting core features of human adipocyte beiging. Unexpectedly, we found that Fsk-induced UCP1 expression was reduced by approximately 80% following CRISPR-Cas9-mediated knockout of PNPLA2, the gene encoding the triglyceride lipase ATGL. As anticipated, ATGL knockout suppressed lipolysis; however, the associated suppression of UCP1 induction indicates that maximal cAMP-mediated UCP1 induction requires products of ATGL-catalyzed lipolysis. Supporting this, we observed that the reduction in Fsk-stimulated UCP1 induction caused by ATGL knockout was reversed by Rsg, implying that the role of lipolysis in this process is to generate natural PPAR{gamma} agonists. ConclusionUCP1 transcription is known to be stimulated by transcription factors activated downstream of cAMP-dependent protein kinases. Here we demonstrate that UCP1 transcription can also be acutely induced through PPAR{gamma}-activation. Moreover, both pathways are activated in human adipocytes in response to cAMP, synergistically inducing UCP1 expression. The stimulation of PPAR{gamma} in response to cAMP occurs as a result of the production of natural PPAR{gamma} activating ligands through ATGL-mediated lipolysis. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=161 SRC="FIGDIR/small/607465v1_ufig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@18675a5org.highwire.dtl.DTLVardef@95cb66org.highwire.dtl.DTLVardef@5cb189org.highwire.dtl.DTLVardef@18bac05_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2023

Regulation of lipolysis by 14-3-3 proteins on human adipocyte lipid droplets.

Adipocyte lipid droplets (LDs) play a crucial role in systemic lipid metabolism by storing and releasing lipids to meet the organisms energy needs. Hormonal signals such as catecholamines and insulin act on adipocyte LDs, and impaired responsiveness to these signals can lead to uncontrolled lipolysis, lipotoxicity, and a higher risk of metabolic diseases. To investigate the mechanisms that control LD function in human adipocytes, we employed techniques to obtain mesenchymal progenitor cells on a large scale and applied proximity labeling mediated by enhanced ascorbate peroxidase (APEX2) to identify the interactome of PLIN1 in differentiated adipocytes. We identified 70 proteins that interact specifically with PLIN1, including PNPLA2 and LIPE, which are the primary effectors of regulated triglyceride hydrolysis, and four members of the 14-3-3 protein family (YWHAB, YWHAE, YWHAZ, and YWHAG), which are known to regulate diverse signaling pathways. Functional studies showed that YWHAB is required for maximum cAMP-stimulated lipolysis and helps to mitigate the anti-lipolytic effects of insulin. These findings reveal new regulatory mechanisms that control lipolysis in human metabolism. SIGNIFICANCE STATEMENTLipid droplets are ubiquitous cytoplasmic organelles that store metabolic energy and play a key role in cellular lipid metabolism (1). Adipocyte LDs play an additional, crucial role, as they supply the energy needs of the whole body through hormonally regulated triglyceride synthesis, storage, and release. The mechanisms by which adipocyte lipid droplets release lipids for systemic use has been mostly studied in mouse models and cell lines. To understand how lipid mobilization is controlled in human adipocytes, we used proximity labeling to identify proteins that interact with PLIN1, a major component of the lipid droplet, in adipocytes generated from primary human progenitor cells. Our study catalogues the interactome of human PLIN1 and identifies previously unrecognized potential mechanism for control of human adipocyte lipolysis through 14-3-3 proteins.

cell biology↗

bioRxiv2021

A NEUROGENIC GENE EXPRESSION SIGNATURE SUPPORTS HUMAN THERMOGENIC ADIPOSE TISSUE DEVELOPMENT IN VIVO.

Mechanisms that control "beige/brite" thermogenic adipose tissue development may be harnessed to improve human metabolic health. To define these mechanisms, we developed a species-hybrid model in which human mesenchymal progenitor cells were used to develop white or thermogenic/beige adipose tissue in mice. The hybrid adipose tissue developed distinctive features of human adipose tissue, such as larger adipocyte size, despite its neurovascular architecture being entirely of murine origin. Thermogenic adipose tissue recruited a denser, qualitatively distinct vascular network, differing in genes mapping to circadian rhythm pathways, and denser sympathetic innervation. The enhanced thermogenic neurovascular network was associated with human adipocyte expression of THBS4, TNC, NTRK3 and SPARCL1, which enhance neurogenesis, and decreased expression of MAOA and ACHE, which control neurotransmitter tone. Systemic inhibition of MAOA, which is present in human but absent in mouse adipocytes, induced browning of human but not mouse adipose tissue, revealing the physiological relevance of this pathway. Our results reveal species-specific cell type dependencies controlling the development of thermogenic adipose tissue and point to human adipocyte MAOA as a potential target for metabolic disease therapy.

developmental biology↗