Obesity and type 2 diabetes are associated with disturbances in insulin-regulated glucose and lipid fluxes and severe comorbidities including cardiovascular disease and steatohepatitis. Whole body metabolism is regulated by lipid-storing white adipocytes as well as "brown" and "brite/beige" adipocytes that express thermogenic uncoupling protein 1 (UCP1) and secrete factors favorable to metabolic health. Implantation of brown fat into obese mice improves glucose tolerance, but translation to humans has been stymied by low abundance of primary human beige adipocytes. Here we apply methods to greatly expand human adipocyte progenitors from small samples of human subcutaneous adipose tissue and then disrupt the thermogenic suppressor gene NRIP1 by CRISPR. Ribonucleoprotein consisting of Cas9 and sgRNA delivered ex vivo are fully degraded by the human cells following high efficiency NRIP1 depletion without detectable off-target editing. Implantation of such CRISPR-enhanced human or mouse brown-like adipocytes into high fat diet fed mice decreases adiposity and liver triglycerides while enhancing glucose tolerance compared to implantation with unmodified adipocytes. These findings advance a therapeutic strategy to improve metabolic homeostasis through CRISPR-based genetic enhancement of human adipocytes without exposing the recipient to immunogenic Cas9 or delivery vectors.
- MeSH
- bílé tukové buňky metabolismus MeSH
- buněčná diferenciace MeSH
- buněčné kultury metody MeSH
- CRISPR-Cas systémy genetika MeSH
- dieta s vysokým obsahem tuků škodlivé účinky MeSH
- dospělé kmenové buňky fyziologie MeSH
- editace genu metody MeSH
- guide RNA, Kinetoplastida genetika MeSH
- hnědé tukové buňky metabolismus transplantace MeSH
- lidé MeSH
- metabolismus lipidů genetika MeSH
- modely nemocí na zvířatech MeSH
- myši MeSH
- nuclear receptor interacting protein 1 genetika metabolismus MeSH
- obezita komplikace metabolismus terapie MeSH
- podkožní tuk cytologie MeSH
- porucha glukózové tolerance etiologie metabolismus terapie MeSH
- termogeneze genetika MeSH
- ztučnělá játra etiologie metabolismus prevence a kontrola MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
Here, we show that β adrenergic signaling coordinately upregulates de novo lipogenesis (DNL) and thermogenesis in subcutaneous white adipose tissue (sWAT), and both effects are blocked in mice lacking the cAMP-generating G protein-coupled receptor Gs (Adipo-GsαKO) in adipocytes. However, UCP1 expression but not DNL activation requires rapamycin-sensitive mTORC1. Furthermore, β3-adrenergic agonist CL316243 readily upregulates thermogenic but not lipogenic genes in cultured adipocytes, indicating that additional regulators must operate on DNL in sWAT in vivo. We identify one such factor as thyroid hormone T3, which is elevated locally by adrenergic signaling. T3 administration to wild-type mice enhances both thermogenesis and DNL in sWAT. Mechanistically, T3 action on UCP1 expression in sWAT depends upon cAMP and is blocked in Adipo-GsαKO mice even as elevated DNL persists. Thus, T3 enhances sWAT thermogenesis by amplifying cAMP signaling, while its control of adipocyte DNL can be mediated independently of both cAMP and rapamycin-sensitive mTORC1.
- MeSH
- adrenergní látky metabolismus MeSH
- bílá tuková tkáň metabolismus MeSH
- hnědá tuková tkáň metabolismus MeSH
- hormony štítné žlázy metabolismus MeSH
- lipogeneze fyziologie MeSH
- myši transgenní MeSH
- signální transdukce fyziologie MeSH
- termogeneze genetika MeSH
- tukové buňky metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
OBJECTIVE: Crosstalk between adipocytes and local neurons may be an important regulatory mechanism to control energy homeostasis. We previously reported that perturbation of adipocyte de novo lipogenesis (DNL) by deletion of fatty acid synthase (FASN) expands sympathetic neurons within white adipose tissue (WAT) and stimulates the appearance of "beige" adipocytes. Here we tested whether WAT DNL activity can also influence neuronal regulation and thermogenesis in brown adipose tissue (BAT). METHODS AND RESULTS: Induced deletion of FASN in all adipocytes in mature mice (iAdFASNKO) enhanced sympathetic innervation and neuronal activity as well as UCP1 expression in both WAT and BAT. This increased sympathetic innervation could be observed at both 22 °C and 30 °C, indicating it is not a response to heat loss but rather adipocyte signaling. In contrast, selective ablation of FASN in brown adipocytes of mice (iUCP1FASNKO) failed to modulate sympathetic innervation and the thermogenic program in BAT. Surprisingly, DNL in brown adipocytes was also dispensable in maintaining euthermia when UCP1FASNKO mice were cold-exposed. CONCLUSION: These results indicate that DNL in white adipocytes influences long distance signaling to BAT, which can modify BAT sympathetic innervation and expression of genes involved in thermogenesis.
- MeSH
- adipozita MeSH
- béžové tukové buňky metabolismus MeSH
- bílá tuková tkáň metabolismus MeSH
- bílé tukové buňky metabolismus MeSH
- hnědá tuková tkáň metabolismus MeSH
- hnědé tukové buňky metabolismus MeSH
- lipogeneze MeSH
- myši MeSH
- neurony metabolismus MeSH
- obezita metabolismus MeSH
- signální transdukce MeSH
- syntázy mastných kyselin MeSH
- synthasa mastných kyselin, typ I genetika metabolismus MeSH
- termogeneze MeSH
- termoregulace MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Research Support, N.I.H., Extramural MeSH
BACKGROUND: The de novo biosynthesis of fatty acids (DNL) through fatty acid synthase (FASN) in adipocytes is exquisitely regulated by nutrients, hormones, fasting, and obesity in mice and humans. However, the functions of DNL in adipocyte biology and in the regulation of systemic glucose homeostasis are not fully understood. METHODS & RESULTS: Here we show adipocyte DNL controls crosstalk to localized sympathetic neurons that mediate expansion of beige/brite adipocytes within inguinal white adipose tissue (iWAT). Induced deletion of FASN in white and brown adipocytes of mature mice (iAdFASNKO mice) enhanced glucose tolerance, UCP1 expression, and cAMP signaling in iWAT. Consistent with induction of adipose sympathetic nerve activity, iAdFASNKO mice displayed markedly increased neuronal tyrosine hydroxylase (TH) and neuropeptide Y (NPY) content in iWAT. In contrast, brown adipose tissue (BAT) of iAdFASNKO mice showed no increase in TH or NPY, nor did FASN deletion selectively in brown adipocytes (UCP1-FASNKO mice) cause these effects in iWAT. CONCLUSIONS: These results demonstrate that downregulation of fatty acid synthesis via FASN depletion in white adipocytes of mature mice can stimulate neuronal signaling to control thermogenic programming in iWAT.
- MeSH
- AMP cyklický metabolismus MeSH
- krevní glukóza metabolismus MeSH
- kultivované buňky MeSH
- lipogeneze * MeSH
- mastné kyseliny biosyntéza MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- neurony metabolismus fyziologie MeSH
- neuropeptid Y metabolismus MeSH
- sympatický nervový systém cytologie fyziologie MeSH
- syntázy mastných kyselin metabolismus MeSH
- termogeneze * MeSH
- tukové buňky metabolismus MeSH
- tyrosin-3-monooxygenasa metabolismus MeSH
- uncoupling protein 1 metabolismus MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Research Support, N.I.H., Extramural MeSH
Mitogen-activated kinase kinase kinase kinase 4 (Map4k4), originally identified in small interfering (si)RNA screens and characterized by tissue-specific gene deletions, is emerging as a regulator of glucose homeostasis and cardiovascular health. Recent studies have shown that Map4k4 gene ablation or inhibition of its kinase activity attenuates hyperglycemia and plaque formation in mouse models of insulin resistance and atherosclerosis, and suggest roles for Map4k4 in multiple signaling systems, including NFκB activation, small GTPase regulation, the Hippo cascade, and regulation of cell dynamics by FERM domain proteins. This new and promising area of inquiry raises key questions that need to be addressed, such as defining which of the above or other effectors mediate Map4k4 control of metabolic and vascular functions, and identifying upstream activators of Map4k4.
- MeSH
- ateroskleróza genetika metabolismus MeSH
- fosforylace genetika fyziologie MeSH
- intracelulární signální peptidy a proteiny genetika metabolismus MeSH
- inzulinová rezistence genetika fyziologie MeSH
- kardiovaskulární nemoci genetika metabolismus MeSH
- lidé MeSH
- protein-serin-threoninkinasy genetika metabolismus MeSH
- signální transdukce genetika fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Research Support, N.I.H., Extramural MeSH
Diabetes is associated with dire peripheral sequelae including foot ulcers and amputations. A recent article by Wong et al. demystifies this connection by demonstrating that the neutrophil defense mechanism of extruding decondensed chromatin, termed NETosis, mediates delayed wound healing in diabetes and provides a therapeutic strategy for this indication.
- MeSH
- citrulin metabolismus MeSH
- extracelulární pasti * účinky léků MeSH
- hojení ran * účinky léků MeSH
- hydrolasy genetika metabolismus MeSH
- komplikace diabetu patologie MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Adipose tissue (AT) of obese mice and humans accumulates immune cells, which secrete cytokines that can promote insulin resistance. AT macrophages (ATMs) are thought to originate from bone-marrow-derived monocytes, which infiltrate the tissue from the circulation. Here, we show that a major fraction of macrophages unexpectedly undergo cell division locally within AT, as detected by Ki67 expression and 5-ethynyl-2'-deoxyuridine incorporation. Macrophages within the visceral AT (VAT), but not those in other tissues (including liver and spleen), displayed increased proliferation in obesity. Importantly, depletion of blood monocytes had no impact on ATM content, whereas their proliferation in situ continued. Treatment with monocyte chemotactic protein 1 (MCP-1) induced macrophage cell division in AT explants, whereas mcp-1 deficiency in vivo decreased ATM proliferation. These results reveal that, in addition to blood monocyte recruitment, in situ proliferation driven by MCP-1 is an important process by which macrophages accumulate in the VAT in obesity.
- MeSH
- antigen Ki-67 metabolismus MeSH
- biologické markery metabolismus MeSH
- buněčné dělení MeSH
- chemokin CCL2 metabolismus MeSH
- lidé MeSH
- makrofágy metabolismus patologie MeSH
- monocyty metabolismus MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- obezita metabolismus patologie MeSH
- proliferace buněk MeSH
- tuková tkáň patologie MeSH
- zánět patologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH