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Brisnovali, N. F.

Publications and source records attributed to Brisnovali, N. F..

3 recordsLinked to original sources

Regulatory T cells establish an IL-10-IL10R immunometabolic checkpoint that limits HSL activation and lipolysis

Adipose tissue harbors a significant population of regulatory T (Treg) cells that enforce immune homeostasis, yet whether Tregs function as an immunometabolic checkpoint to directly regulate core adipocyte signaling programs remains incompletely defined. Here we show that adipose Tregs function as a dominant, time-dependent checkpoint on {beta}-adrenergic signal-driven lipolytic program and signal transduction in adipocytes. Our integrated scRNA-seq, flow cytometry, and phosphoproteomics data show that prolonged adrenergic stimulation induces a progressive attenuation of activation of key lipase hormone-sensitive lipase (HSL) that coincides with Treg depletion in circulation and accumulation within white adipose tissue. Genetic perturbations establish Treg-derived interleukin-10 (IL-10) as the key mediator of this brake. IL-10 signaling through adipocyte IL-10R suppresses adrenergic HSL activation and rewires downstream signaling nodes that govern catecholamine responsiveness, lipolysis, and systemic energy homeostasis. Mechanistically, IL-10R engages a STAT3-dependent transcriptional program that induces the G-protein regulators RGS2 and RGS3, diminished PKA flux to HSL that reinforces suppression of the HSL activation state and lipolysis. Together, these findings define an adrenergic-immune feedback circuit in which Tregs fine tune the amplitude and duration of catecholamine responsiveness in adipocytes, establishing immune control of a core lipolytic pathway with implications for obesity-associated adipose dysfunction.

cell biology↗

Tetherin enforces an immunometabolic checkpoint that coordinates glycolytic and interferon signaling in adipocytes

Coordination between innate immune signaling and glucose metabolism is fundamental to organismal homeostasis, yet despite decades of study linking immunity and metabolism, the mechanisms by which metabolic cells restrain antiviral innate signaling while preserving glycolytic competence during overnutrition remain poorly defined. Here we identify Tetherin (BST2) as a unique cell-intrinsic immunometabolic checkpoint that couples restraint of type I interferon (IFN-I) signaling to preservation of glycolytic capacity in adipocytes. Tetherin localizes to endoplasmic reticulum and organizes an interactome enriched for antiviral sensing regulators and glycolytic control nodes in adipocytes. Mechanistically, Tetherin directly engages the ubiquitin-dependent degradation machinery NDFIP1 and RNF128 to terminate IRF3 activation, thereby limiting pro-inflammatory, anti-glycolytic signaling and protecting adipocytes from metabolic dysfunction. In parallel, multiomics integration reveals that Tetherin also acts as a scaffold that binds and spatially organizes and activates PFKFB3 to increase glycolytic capacity and restrain MAVS-IRF3 innate immune signalling. In vivo, adipocyte-specific loss of Tetherin amplifies high sucrose diet and high-fat-diet-induced glucose intolerance and liver steatosis, whereas overexpression of human Tetherin in adipocyte suppresses obesity-driven interferon signaling, restores glycolytic pathway, and improves metabolic homeostasis. Orthogonal perturbations in cancer and insulinoma cells further confirm an immunometabolic role for Tetherin. Together, these findings define Tetherin as a dual node immunometabolic checkpoint that couples restraint of antiviral innate inflammatory signaling to maintenance of glycolytic competence, thereby safeguarding adipocyte metabolic homeostasis.

cell biology↗

Effects of SGLT2 Ablation or Inhibition on Corticosterone Secretion in High-Fat-Fed Mice: Exploring a Nexus with Cytokine Levels

Despite recent therapeutic advances, achieving optimal glycaemic control remains a challenge in managing Type 2 Diabetes (T2D). Sodium-glucose co-transporter type 2 (SGLT2) inhibitors have emerged as effective treatments by promoting urinary glucose excretion. However, the full scope of their mechanisms extends beyond glycaemic control. At present, their immunometabolic effects remain elusive. To investigate the effects of SGLT2 inhibition or deletion, we compared the metabolic and immune phenotype between high fat diet-fed control, chronically dapagliflozin-treated mice and total-body SGLT2/Slc5a2 knockout mice. SGLT2 null mice exhibited superior glucose tolerance and insulin sensitivity compared to control or dapagliflozin-treated mice, independent of glycosuria and body weight. Moreover, SGLT2 null mice demonstrated physiological regulation of corticosterone secretion, with lowered morning levels compared to control mice. Systemic cytokine profiling also unveiled significant alterations in inflammatory mediators, particularly interleukin 6 (IL-6). Furthermore, unbiased proteomic analysis demonstrated downregulation of acute-phase proteins and upregulation of glutathione-related proteins, suggesting a role in the modulation of antioxidant responses. Conversely, IL-6 increased SGLT2 expression in kidney HK2 cells suggesting a role for cytokines in the effects of hyperglycemia. Collectively, our study elucidates a potential interplay between SGLT2 activity, immune modulation, and metabolic homeostasis. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=193 HEIGHT=200 SRC="FIGDIR/small/590099v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@140041forg.highwire.dtl.DTLVardef@1ceb1b7org.highwire.dtl.DTLVardef@f575b1org.highwire.dtl.DTLVardef@101d5b4_HPS_FORMAT_FIGEXP M_FIG C_FIG Article HighlightsO_LIThe role of Sodium-glucose co-transporter type 2 (SGLT2) in immunity regulation remains elusive, despite extensive research in SGLT2 inhibitors. C_LIO_LIWe sought to discern the effects of SGLT2 inhibition or deletion on metabolic and immune profiles in high-fat-fed mice, focussing on corticosterone regulation and cytokine alterations. C_LIO_LISGLT2 null mice exhibit enhanced insulin sensitivity, alongside physiologically regulated corticosterone levels and significant alterations in inflammatory cytokines, and we identified changes in protein expression suggestive of antioxidant modulation. C_LIO_LIOur findings emphasize the interplay between immune responses and metabolic regulation mediated by SGLT2 activity. C_LI

cell biology↗