Articles

Activation of brown adipose tissue can ameliorate obesity and diabetes. Here the authors show that chemical inhibition of hyaluronan synthesis by 4‐methylumbelliferone or genetic deletion of hyaluronan synthases 2 and 3 decreases body-weight gain and improves glucose homeostasis by inducing the thermogenic capacity of brown adipose tissue in mice.

Relapsed disease after conventional cancer treatments is an obstacle in epidermal growth factor receptor (EGFR)-based targeted therapy. Here the authors show that tolerance to the EGFR inhibitor osimertinib in non-small-cell lung cancer is mediated by the effects of miR-147b on the tricarboxylic acid cycle and pseudohypoxia pathways, which can be manipulated with a miR-147b inhibitor.

Inoue et al. use genetic and epigenetic tools to map active gene regulatory elements in leptin-responsive neurons in the mouse hypothalamus. These regulatory elements overlap with several obesity-associated GWAS SNPs.

Here the authors identify the long noncoding RNA lnc-ob1 as a regulator of osteoblast activity. Increased lnc-ob1 expression in osteoblasts, owing to either genetic knock-in or pharmacological delivery of a plasmid, increases bone formation and counteracts bone loss in an osteoporosis mouse model, thus suggesting that modulating lnc-ob1 expression may be therapeutically useful.

Proinflammatory activation of liver macrophages and their secretion of proinflammatory cytokines have been linked to obesity. Here Morgantini et al. report a mechanism through which liver macrophages can impair liver metabolism and promote insulin resistance in obesity in the absence of an overt proinflammatory phenotype, through secretion of non-inflammatory factors such as IGFBP7.

The conventional view holds that hypoxia confers drug resistance. In contrast, here the authors use a multilayer ‘omics data approach to characterize the molecular features associated with tumour hypoxia and identify molecular alterations that correlate with both drug-resistant and drug-sensitive responses to approved drugs.

Amino acids are required for cell survival and growth. However, the different requirements of amino acid metabolic pathways in normal haematopoiesis and leukaemogenesis have not been explored. Here the authors focus on the transporter of neutral amino acids and show that malignant blood cells rely more on ASCT2-mediated amino acid metabolism than normal cells.

The oxidative pentose-phosphate pathway (oxPPP) is a major NADPH producer. Here the authors show that malic enzyme or isocitrate dehydrogenase can support the growth of cells lacking the oxPPP, but the oxPPP is necessary to maintain a normal NADPH/NADP ratio, DHFR activity and folate metabolism.

Obesity is associated with an increased risk of colitis-associated cancer (CAC). Here Ostermann et al. show that a high-fat diet induces insulin resistance in intestinal epithelial cells (IECs) and that genetic inactivation of insulin and IGF1 signalling in IECs impairs intestinal regeneration and enhances tumour formation in a CAC mouse model.

Creatine can be used for thermogenesis in adipocytes. Here Kazak et al. show that creatine uptake is required to sustain this thermogenic pathway. Knockdown of the creatine transporter, CrT, in adipocytes decreases thermogenesis and energy expenditure, whereas creatine supplementation increases energy expenditure in mice fed a high-fat diet.

Many beneficial effects of exercise are mediated by factors secreted from the exercising muscle, so-called myokines. Here, the authors identify what might be the first exercised-induced adipokine, TGF-β2, which is secreted from subcutaneous fat in response to exercise-induced increases in serum lactate levels and has beneficial metabolic effects in mice.

Hypothalamic melanocortin neurons control energy homoeostasis by modulating appetite. Here, the authors reveal a role for the transcription factor Tbx3 as a regulator of the peptidergic identity and function of immature and mature mouse melanocortin neurons.

Bone marrow-derived cells can rapidly enter the systemic circulation, but how this is achieved is unclear. Grüneboom et al. identify tiny capillaries, termed trans-cortical vessels (TCVs), that connect the bone marrow cavity to the systemic vasculature, and show that the majority of blood in long bones passes through TCVs.

ACC1 is a rate-limiting enzyme during fatty acid biosynthesis. Here the authors describe how loss of ACC1 enhances CD4⁺ memory T cell formation and improves outcome in a murine model of parasite infection, indicating that lipid biosynthesis directs cell-fate determination during the generation of memory T cells.

As opposed to circulating factors that promote energy expenditure, hormones that suppress energy expenditure have remained largely elusive. Here, Wang et al. show that the hepatokine Tsukushi is upregulated in obesity and inhibits sympathetic activity and thermogenesis in fat by promoting whitening.

Ageing is associated with deteriorating immune function and metabolic diseases. Here, the authors show that plasma levels of the stress-response protein MANF decline with age in various organisms and that MANF has beneficial effects on immune and metabolic function, particularly in the liver, in old mice.

Extracellular matrix (ECM) homeostasis is essential for normal tissue function, and its perturbation by injury, trauma or disease results in fibrosis. Here, the authors show that glycolysis and the fatty acid oxidation pathway regulate fibroblast behaviour and have reciprocal effects in ECM upregulation and downregulation, respectively.

Despite the similarity of metabolic flux patterns in different organisms, the underlying governing principles remain unclear. Using a constraint-based thermodynamic–stoichiometric model as well as quantitative metabolome and physiological data, Niebel et al. identify an upper limit on the cellular Gibbs energy dissipation rate, which could shape metabolism across organisms.

Nicotinamide mononucleotide (NMN) is a biosynthetic precursor of NAD⁺, but how NMN is taken up into cells has not been entirely clear. Here the authors discover a specific NMN transporter, encoded by the Slc12a8 gene, which regulates NMN uptake and cellular NAD⁺ levels in vitro and in the mouse intestine in vivo.

Transferrin receptor 2 (Trf2) is known to regulate iron homeostasis through its action in the liver. Here the authors report a previously unrecognised role of Trf2 in regulating bone homeostasis mediated by modulation of BMP signalling specifically on osteoblasts.