Pub Date : 2024-10-28DOI: 10.1016/j.cmet.2024.10.014
Joyce Y. Liu, Ramya S. Kuna, Laura V. Pinheiro, Phuong T.T. Nguyen, Jaclyn E. Welles, Jack M. Drummond, Nivitha Murali, Prateek Sharma, Julianna G. Supplee, Mia Shiue, Steven Zhao, Aimee T. Farria, Avi Kumar, Mauren L. Ruchhoeft, Christina Demetriadou, Daniel S. Kantner, Adam Chatoff, Emily Megill, Paul M. Titchenell, Nathaniel W. Snyder, Kathryn E. Wellen
ATP citrate lyase (ACLY) synthesizes acetyl-CoA for de novo lipogenesis (DNL), which is elevated in metabolic dysfunction-associated steatotic liver disease. Hepatic ACLY is inhibited by the LDL-cholesterol-lowering drug bempedoic acid (BPA), which also improves steatosis in mice. While BPA potently suppresses hepatic DNL and increases fat catabolism, it is unclear if ACLY is its primary molecular target in reducing liver triglyceride. We show that on a Western diet, loss of hepatic ACLY alone or together with the acetyl-CoA synthetase ACSS2 unexpectedly exacerbates steatosis, linked to reduced PPARα target gene expression and fatty acid oxidation. Importantly, BPA treatment ameliorates Western diet-mediated triacylglyceride accumulation in both WT and liver ACLY knockout mice, indicating that its primary effects on hepatic steatosis are ACLY independent. Together, these data indicate that hepatic ACLY plays an unexpected role in restraining diet-dependent lipid accumulation and that BPA exerts substantial effects on hepatic lipid metabolism independently of ACLY.
ATP 柠檬酸裂解酶(ACLY)合成乙酰-CoA,用于新生脂肪生成(DNL),在代谢功能障碍相关性脂肪肝中,DNL 会升高。降低低密度脂蛋白胆固醇的药物贝门冬氨酸(BPA)可抑制肝脏乙酰胆碱转化酶(ACLY),这也会改善小鼠的脂肪变性。虽然 BPA 能有效抑制肝脏 DNL 并增加脂肪分解,但尚不清楚 ACLY 是否是其降低肝脏甘油三酯的主要分子靶点。我们的研究表明,在西式饮食中,肝脏 ACLY 单独或与乙酰-CoA 合成酶 ACSS2 一起缺失会意外加剧脂肪变性,这与 PPARα 靶基因表达和脂肪酸氧化减少有关。重要的是,在 WT 小鼠和肝脏 ACLY 基因敲除小鼠中,双酚 A 处理可改善西方饮食介导的三酰甘油积累,这表明双酚 A 对肝脏脂肪变性的主要影响与 ACLY 无关。这些数据共同表明,肝脏 ACLY 在抑制饮食依赖性脂质积累方面发挥了意想不到的作用,而且双酚 A 对肝脏脂质代谢产生的实质性影响与 ACLY 无关。
{"title":"Bempedoic acid suppresses diet-induced hepatic steatosis independently of ATP-citrate lyase","authors":"Joyce Y. Liu, Ramya S. Kuna, Laura V. Pinheiro, Phuong T.T. Nguyen, Jaclyn E. Welles, Jack M. Drummond, Nivitha Murali, Prateek Sharma, Julianna G. Supplee, Mia Shiue, Steven Zhao, Aimee T. Farria, Avi Kumar, Mauren L. Ruchhoeft, Christina Demetriadou, Daniel S. Kantner, Adam Chatoff, Emily Megill, Paul M. Titchenell, Nathaniel W. Snyder, Kathryn E. Wellen","doi":"10.1016/j.cmet.2024.10.014","DOIUrl":"https://doi.org/10.1016/j.cmet.2024.10.014","url":null,"abstract":"ATP citrate lyase (ACLY) synthesizes acetyl-CoA for <em>de novo</em> lipogenesis (DNL), which is elevated in metabolic dysfunction-associated steatotic liver disease. Hepatic ACLY is inhibited by the LDL-cholesterol-lowering drug bempedoic acid (BPA), which also improves steatosis in mice. While BPA potently suppresses hepatic DNL and increases fat catabolism, it is unclear if ACLY is its primary molecular target in reducing liver triglyceride. We show that on a Western diet, loss of hepatic ACLY alone or together with the acetyl-CoA synthetase ACSS2 unexpectedly exacerbates steatosis, linked to reduced PPARα target gene expression and fatty acid oxidation. Importantly, BPA treatment ameliorates Western diet-mediated triacylglyceride accumulation in both WT and liver ACLY knockout mice, indicating that its primary effects on hepatic steatosis are ACLY independent. Together, these data indicate that hepatic ACLY plays an unexpected role in restraining diet-dependent lipid accumulation and that BPA exerts substantial effects on hepatic lipid metabolism independently of ACLY.","PeriodicalId":9840,"journal":{"name":"Cell metabolism","volume":null,"pages":null},"PeriodicalIF":29.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-28DOI: 10.1016/j.cmet.2024.10.013
Adam J. Rauckhorst, Ryan D. Sheldon, Daniel J. Pape, Adnan Ahmed, Kelly C. Falls-Hubert, Ronald A. Merrill, Reid F. Brown, Kshitij Deshmukh, Thomas A. Vallim, Stanislaw Deja, Shawn C. Burgess, Eric B. Taylor
Hepatic de novo lipogenesis (DNL) is a fundamental physiologic process that is often pathogenically elevated in metabolic disease. Treatment is limited by incomplete understanding of the metabolic pathways supplying cytosolic acetyl-CoA, the obligate precursor to DNL, including their interactions and proportional contributions. Here, we combined extensive 13C tracing with liver-specific knockout of key mitochondrial and cytosolic proteins mediating cytosolic acetyl-CoA production. We show that the mitochondrial pyruvate carrier (MPC) and ATP-citrate lyase (ACLY) gate the major hepatic lipogenic acetyl-CoA production pathway, operating in parallel with acetyl-CoA synthetase 2 (ACSS2). Given persistent DNL after mitochondrial citrate carrier (CiC) and ACSS2 double knockout, we tested the contribution of exogenous and leucine-derived acetoacetate to acetoacetyl-CoA synthetase (AACS)-dependent DNL. CiC knockout increased acetoacetate-supplied hepatic acetyl-CoA production and DNL, indicating that ketones function as mitochondrial-citrate reciprocal DNL precursors. By delineating a mitochondrial-cytosolic DNL substrate supply network, these findings may inform strategies to therapeutically modulate DNL.
{"title":"A hierarchical hepatic de novo lipogenesis substrate supply network utilizing pyruvate, acetate, and ketones","authors":"Adam J. Rauckhorst, Ryan D. Sheldon, Daniel J. Pape, Adnan Ahmed, Kelly C. Falls-Hubert, Ronald A. Merrill, Reid F. Brown, Kshitij Deshmukh, Thomas A. Vallim, Stanislaw Deja, Shawn C. Burgess, Eric B. Taylor","doi":"10.1016/j.cmet.2024.10.013","DOIUrl":"https://doi.org/10.1016/j.cmet.2024.10.013","url":null,"abstract":"Hepatic <em>de novo</em> lipogenesis (DNL) is a fundamental physiologic process that is often pathogenically elevated in metabolic disease. Treatment is limited by incomplete understanding of the metabolic pathways supplying cytosolic acetyl-CoA, the obligate precursor to DNL, including their interactions and proportional contributions. Here, we combined extensive <sup>13</sup>C tracing with liver-specific knockout of key mitochondrial and cytosolic proteins mediating cytosolic acetyl-CoA production. We show that the mitochondrial pyruvate carrier (MPC) and ATP-citrate lyase (ACLY) gate the major hepatic lipogenic acetyl-CoA production pathway, operating in parallel with acetyl-CoA synthetase 2 (ACSS2). Given persistent DNL after mitochondrial citrate carrier (CiC) and ACSS2 double knockout, we tested the contribution of exogenous and leucine-derived acetoacetate to acetoacetyl-CoA synthetase (AACS)-dependent DNL. CiC knockout increased acetoacetate-supplied hepatic acetyl-CoA production and DNL, indicating that ketones function as mitochondrial-citrate reciprocal DNL precursors. By delineating a mitochondrial-cytosolic DNL substrate supply network, these findings may inform strategies to therapeutically modulate DNL.","PeriodicalId":9840,"journal":{"name":"Cell metabolism","volume":null,"pages":null},"PeriodicalIF":29.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fructose is associated with colorectal cancer tumorigenesis and metastasis through ketohexokinase-mediated metabolism in the colorectal epithelium, yet its role in the tumor immune microenvironment remains largely unknown. Here, we show that a modest amount of fructose, without affecting obesity and associated complications, promotes colorectal cancer tumorigenesis and growth by suppressing the polarization of M1-like macrophages. Fructose inhibits M1-like macrophage polarization independently of fructose-mediated metabolism. Instead, it serves as a signal molecule to promote the interaction between hexokinase 2 and inositol 1,4,5-trisphophate receptor type 3, the predominant Ca2+ channel on the endoplasmic reticulum. The interaction reduces Ca2+ levels in cytosol and mitochondria, thereby suppressing the activation of mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 1 (STAT1) as well as NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome activation. Consequently, this impedes M1-like macrophage polarization. Our study highlights the critical role of fructose as a signaling molecule that impairs the polarization of M1-like macrophages for tumor growth.
{"title":"Hexokinase 2 senses fructose in tumor-associated macrophages to promote colorectal cancer growth","authors":"Huiwen Yan, Zhi Wang, Da Teng, Xiaodong Chen, Zijing Zhu, Huan Chen, Wen Wang, Ziyuan Wei, Zhenzhen Wu, Qian Chai, Fei Zhang, Youwang Wang, Kaile Shu, Shaotang Li, Guizhi Shi, Mingzhao Zhu, Hai-long Piao, Xian Shen, Pengcheng Bu","doi":"10.1016/j.cmet.2024.10.002","DOIUrl":"https://doi.org/10.1016/j.cmet.2024.10.002","url":null,"abstract":"Fructose is associated with colorectal cancer tumorigenesis and metastasis through ketohexokinase-mediated metabolism in the colorectal epithelium, yet its role in the tumor immune microenvironment remains largely unknown. Here, we show that a modest amount of fructose, without affecting obesity and associated complications, promotes colorectal cancer tumorigenesis and growth by suppressing the polarization of M1-like macrophages. Fructose inhibits M1-like macrophage polarization independently of fructose-mediated metabolism. Instead, it serves as a signal molecule to promote the interaction between hexokinase 2 and inositol 1,4,5-trisphophate receptor type 3, the predominant Ca<sup>2+</sup> channel on the endoplasmic reticulum. The interaction reduces Ca<sup>2+</sup> levels in cytosol and mitochondria, thereby suppressing the activation of mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 1 (STAT1) as well as NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome activation. Consequently, this impedes M1-like macrophage polarization. Our study highlights the critical role of fructose as a signaling molecule that impairs the polarization of M1-like macrophages for tumor growth.","PeriodicalId":9840,"journal":{"name":"Cell metabolism","volume":null,"pages":null},"PeriodicalIF":29.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Increased de novo lipogenesis is a hallmark of metabolic dysfunction-associated steatotic liver disease (MASLD) in obesity, but the macronutrient carbon source for over half of hepatic fatty acid synthesis remains undetermined. Here, we discover that dietary protein, rather than carbohydrates or fat, is the primary nutritional risk factor for MASLD in humans. Consistently, ex vivo tracing studies identify amino acids as a major carbon supplier for the tricarboxylic acid (TCA) cycle and lipogenesis in isolated mouse hepatocytes. In vivo, dietary amino acids are twice as efficient as glucose in fueling hepatic fatty acid synthesis. The onset of obesity further drives amino acids into fatty acid synthesis through reductive carboxylation, while genetic and chemical interventions that divert amino acid carbon away from lipogenesis alleviate hepatic steatosis. Finally, low-protein diets (LPDs) not only prevent body weight gain in obese mice but also reduce hepatic lipid accumulation and liver damage. Together, this study uncovers the significant role of amino acids in hepatic lipogenesis and suggests a previously unappreciated nutritional intervention target for MASLD.
{"title":"Amino acid is a major carbon source for hepatic lipogenesis","authors":"Yilie Liao, Qishan Chen, Lei Liu, Haipeng Huang, Jingyun Sun, Xiaojie Bai, Chenchen Jin, Honghao Li, Fangfang Sun, Xia Xiao, Yahong Zhang, Jia Li, Weiping Han, Suneng Fu","doi":"10.1016/j.cmet.2024.10.001","DOIUrl":"https://doi.org/10.1016/j.cmet.2024.10.001","url":null,"abstract":"Increased <em>de novo</em> lipogenesis is a hallmark of metabolic dysfunction-associated steatotic liver disease (MASLD) in obesity, but the macronutrient carbon source for over half of hepatic fatty acid synthesis remains undetermined. Here, we discover that dietary protein, rather than carbohydrates or fat, is the primary nutritional risk factor for MASLD in humans. Consistently, <em>ex vivo</em> tracing studies identify amino acids as a major carbon supplier for the tricarboxylic acid (TCA) cycle and lipogenesis in isolated mouse hepatocytes. <em>In vivo</em>, dietary amino acids are twice as efficient as glucose in fueling hepatic fatty acid synthesis. The onset of obesity further drives amino acids into fatty acid synthesis through reductive carboxylation, while genetic and chemical interventions that divert amino acid carbon away from lipogenesis alleviate hepatic steatosis. Finally, low-protein diets (LPDs) not only prevent body weight gain in obese mice but also reduce hepatic lipid accumulation and liver damage. Together, this study uncovers the significant role of amino acids in hepatic lipogenesis and suggests a previously unappreciated nutritional intervention target for MASLD.","PeriodicalId":9840,"journal":{"name":"Cell metabolism","volume":null,"pages":null},"PeriodicalIF":29.0,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142489629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-24DOI: 10.1016/j.cmet.2024.09.014
Deguan Lv, Deobrat Dixit, Andrea F. Cruz, Leo J.Y. Kim, Likun Duan, Xin Xu, Qiulian Wu, Cuiqing Zhong, Chenfei Lu, Zachary C. Gersey, Ryan C. Gimple, Qi Xie, Kailin Yang, Xiaojing Liu, Xiaoguang Fang, Xujia Wu, Reilly L. Kidwell, Xiuxing Wang, Shideng Bao, Housheng H. He, Jeremy N. Rich
Tumors reprogram their metabolism to generate complex neoplastic ecosystems. Here, we demonstrate that glioblastoma (GBM) stem cells (GSCs) display elevated activity of the malate-aspartate shuttle (MAS) and expression of malate dehydrogenase 2 (MDH2). Genetic and pharmacologic targeting of MDH2 attenuated GSC proliferation, self-renewal, and in vivo tumor growth, partially rescued by aspartate. Targeting MDH2 induced accumulation of alpha-ketoglutarate (αKG), a critical co-factor for dioxygenases, including the N6-methyladenosine (m6A) RNA demethylase AlkB homolog 5, RNA demethylase (ALKBH5). Forced expression of MDH2 increased m6A levels and inhibited ALKBH5 activity, both rescued by αKG supplementation. Reciprocally, targeting MDH2 reduced global m6A levels with platelet-derived growth factor receptor-β (PDGFRβ) as a regulated transcript. Pharmacological inhibition of MDH2 in GSCs augmented efficacy of dasatinib, an orally bioavailable multi-kinase inhibitor, including PDGFRβ. Collectively, stem-like tumor cells reprogram their metabolism to induce changes in their epitranscriptomes and reveal possible therapeutic paradigms.
{"title":"Metabolic regulation of the glioblastoma stem cell epitranscriptome by malate dehydrogenase 2","authors":"Deguan Lv, Deobrat Dixit, Andrea F. Cruz, Leo J.Y. Kim, Likun Duan, Xin Xu, Qiulian Wu, Cuiqing Zhong, Chenfei Lu, Zachary C. Gersey, Ryan C. Gimple, Qi Xie, Kailin Yang, Xiaojing Liu, Xiaoguang Fang, Xujia Wu, Reilly L. Kidwell, Xiuxing Wang, Shideng Bao, Housheng H. He, Jeremy N. Rich","doi":"10.1016/j.cmet.2024.09.014","DOIUrl":"https://doi.org/10.1016/j.cmet.2024.09.014","url":null,"abstract":"Tumors reprogram their metabolism to generate complex neoplastic ecosystems. Here, we demonstrate that glioblastoma (GBM) stem cells (GSCs) display elevated activity of the malate-aspartate shuttle (MAS) and expression of malate dehydrogenase 2 (MDH2). Genetic and pharmacologic targeting of MDH2 attenuated GSC proliferation, self-renewal, and <em>in vivo</em> tumor growth, partially rescued by aspartate. Targeting MDH2 induced accumulation of alpha-ketoglutarate (αKG), a critical co-factor for dioxygenases, including the N6-methyladenosine (m6A) RNA demethylase AlkB homolog 5, RNA demethylase (ALKBH5). Forced expression of MDH2 increased m6A levels and inhibited ALKBH5 activity, both rescued by αKG supplementation. Reciprocally, targeting MDH2 reduced global m6A levels with platelet-derived growth factor receptor-β (PDGFRβ) as a regulated transcript. Pharmacological inhibition of MDH2 in GSCs augmented efficacy of dasatinib, an orally bioavailable multi-kinase inhibitor, including PDGFRβ. Collectively, stem-like tumor cells reprogram their metabolism to induce changes in their epitranscriptomes and reveal possible therapeutic paradigms.","PeriodicalId":9840,"journal":{"name":"Cell metabolism","volume":null,"pages":null},"PeriodicalIF":29.0,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142489006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-22DOI: 10.1016/j.cmet.2024.09.013
Chenxi Zhao, Tingting Zhang, Si-tu Xue, Peitao Zhang, Feng Wang, Yunxuan Li, Ying Liu, Luyao Zhao, Jie Wu, Yechao Yan, Xiaoyun Mao, Yuping Chen, Jian Yuan, Zhuorong Li, Ke Li
Obesity is a major risk factor for poor breast cancer outcomes, but the impact of obesity-induced tumor microenvironment (TME) metabolites on breast cancer growth and metastasis remains unclear. Here, we performed TME metabolomic analysis in high-fat diet (HFD) mouse models and found that glutathione (GSH) levels were elevated in the TME of obesity-accelerated breast cancer. The deletion of glutamate-cysteine ligase catalytic subunit (GCLC), the rate-limiting enzyme in GSH biosynthesis, in adipocytes but not tumor cells reduced obesity-related tumor progression. Mechanistically, we identified that GSH entered tumor cells and directly bound to lysosomal integral membrane protein-2 (scavenger receptor class B, member 2 [SCARB2]), interfering with the interaction between its N and C termini. This, in turn, recruited mTORC1 to lysosomes through ARF1, leading to the activation of mTOR signaling. Overall, we demonstrated that GSH links obesity and breast cancer progression by acting as an activator of mTOR signaling. Targeting the GSH/SCARB2/mTOR axis could benefit breast cancer patients with obesity.
肥胖是导致乳腺癌预后不良的一个主要风险因素,但肥胖引起的肿瘤微环境(TME)代谢物对乳腺癌生长和转移的影响仍不清楚。在这里,我们在高脂饮食(HFD)小鼠模型中进行了TME代谢组学分析,发现在肥胖加速的乳腺癌TME中谷胱甘肽(GSH)水平升高。脂肪细胞中谷胱甘肽-半胱氨酸连接酶催化亚基(GCLC)是谷胱甘肽生物合成的限速酶,而肿瘤细胞中GCLC的缺失可减轻肥胖相关的肿瘤进展。从机理上讲,我们发现 GSH 进入肿瘤细胞后会直接与溶酶体完整膜蛋白-2(清道夫受体 B 类成员 2 [SCARB2])结合,干扰其 N 端和 C 端之间的相互作用。这反过来又通过 ARF1 将 mTORC1 募集到溶酶体,导致 mTOR 信号的激活。总之,我们证明了 GSH 通过作为 mTOR 信号转导的激活剂将肥胖与乳腺癌的进展联系在一起。靶向GSH/SCARB2/mTOR轴可使肥胖症乳腺癌患者获益。
{"title":"Adipocyte-derived glutathione promotes obesity-related breast cancer by regulating the SCARB2-ARF1-mTORC1 complex","authors":"Chenxi Zhao, Tingting Zhang, Si-tu Xue, Peitao Zhang, Feng Wang, Yunxuan Li, Ying Liu, Luyao Zhao, Jie Wu, Yechao Yan, Xiaoyun Mao, Yuping Chen, Jian Yuan, Zhuorong Li, Ke Li","doi":"10.1016/j.cmet.2024.09.013","DOIUrl":"https://doi.org/10.1016/j.cmet.2024.09.013","url":null,"abstract":"Obesity is a major risk factor for poor breast cancer outcomes, but the impact of obesity-induced tumor microenvironment (TME) metabolites on breast cancer growth and metastasis remains unclear. Here, we performed TME metabolomic analysis in high-fat diet (HFD) mouse models and found that glutathione (GSH) levels were elevated in the TME of obesity-accelerated breast cancer. The deletion of glutamate-cysteine ligase catalytic subunit (GCLC), the rate-limiting enzyme in GSH biosynthesis, in adipocytes but not tumor cells reduced obesity-related tumor progression. Mechanistically, we identified that GSH entered tumor cells and directly bound to lysosomal integral membrane protein-2 (scavenger receptor class B, member 2 [SCARB2]), interfering with the interaction between its N and C termini. This, in turn, recruited mTORC1 to lysosomes through ARF1, leading to the activation of mTOR signaling. Overall, we demonstrated that GSH links obesity and breast cancer progression by acting as an activator of mTOR signaling. Targeting the GSH/SCARB2/mTOR axis could benefit breast cancer patients with obesity.","PeriodicalId":9840,"journal":{"name":"Cell metabolism","volume":null,"pages":null},"PeriodicalIF":29.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142486611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-21DOI: 10.1016/j.cmet.2024.09.012
Kenichi Sakamoto, Mary A. Butera, Chunxue Zhou, Giulia Maurizi, Bandy Chen, Li Ling, Adham Shawkat, Likhitha Patlolla, Kavira Thakker, Victor Calle, Donald A. Morgan, Kamal Rahmouni, Gary J. Schwartz, Azeddine Tahiri, Christoph Buettner
The mechanisms underlying obesity-induced insulin resistance remain incompletely understood, as impaired cellular insulin signaling, traditionally considered the primary driver of insulin resistance, does not always accompany impaired insulin action. Overnutrition rapidly increases plasma norepinephrine (NE), suggesting overactivation of the sympathetic nervous system (SNS). However, the role of the SNS in obesity is controversial, as both increased and decreased SNS activity (SNA) have been reported. Here, we show that reducing catecholamine (CA) release from the SNS protects against overnutrition-induced insulin resistance as well as hyperglucagonemia, adipose tissue dysfunction, and fatty liver disease, as we demonstrate utilizing a mouse model of inducible and peripherally restricted deletion of tyrosine hydroxylase (th; THΔper). A key mechanism through which heightened SNA induces insulin resistance is by triggering adipose tissue lipolysis. Increased SNA emerges as a critical driver in the pathogenesis of overnutrition-induced insulin resistance and metabolic disease independent of cellular insulin signaling.
{"title":"Overnutrition causes insulin resistance and metabolic disorder through increased sympathetic nervous system activity","authors":"Kenichi Sakamoto, Mary A. Butera, Chunxue Zhou, Giulia Maurizi, Bandy Chen, Li Ling, Adham Shawkat, Likhitha Patlolla, Kavira Thakker, Victor Calle, Donald A. Morgan, Kamal Rahmouni, Gary J. Schwartz, Azeddine Tahiri, Christoph Buettner","doi":"10.1016/j.cmet.2024.09.012","DOIUrl":"https://doi.org/10.1016/j.cmet.2024.09.012","url":null,"abstract":"The mechanisms underlying obesity-induced insulin resistance remain incompletely understood, as impaired cellular insulin signaling, traditionally considered the primary driver of insulin resistance, does not always accompany impaired insulin action. Overnutrition rapidly increases plasma norepinephrine (NE), suggesting overactivation of the sympathetic nervous system (SNS). However, the role of the SNS in obesity is controversial, as both increased and decreased SNS activity (SNA) have been reported. Here, we show that reducing catecholamine (CA) release from the SNS protects against overnutrition-induced insulin resistance as well as hyperglucagonemia, adipose tissue dysfunction, and fatty liver disease, as we demonstrate utilizing a mouse model of inducible and peripherally restricted deletion of tyrosine hydroxylase (<em>th</em>; THΔper). A key mechanism through which heightened SNA induces insulin resistance is by triggering adipose tissue lipolysis. Increased SNA emerges as a critical driver in the pathogenesis of overnutrition-induced insulin resistance and metabolic disease independent of cellular insulin signaling.","PeriodicalId":9840,"journal":{"name":"Cell metabolism","volume":null,"pages":null},"PeriodicalIF":29.0,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142452392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-15DOI: 10.1016/j.cmet.2024.09.010
Jessie Axsom, Tara TeSlaa, Won Dong Lee, Qingwei Chu, Alexis Cowan, Marc R. Bornstein, Michael D. Neinast, Caroline R. Bartman, Megan C. Blair, Kristina Li, Chelsea Thorsheim, Joshua D. Rabinowitz, Zoltan Arany
Despite the known metabolic benefits of exercise, an integrated metabolic understanding of exercise is lacking. Here, we use in vivo steady-state isotope-labeled infusions to quantify fuel flux and oxidation during exercise in fasted, fed, and exhausted female mice, revealing several novel findings. Exercise strongly promoted glucose fluxes from liver glycogen, lactate, and glycerol, distinct from humans. Several organs spared glucose, a process that broke down in exhausted mice despite concomitant hypoglycemia. Proteolysis increased markedly, also divergent from humans. Fatty acid oxidation dominated during fasted exercise. Ketone production and oxidation rose rapidly, seemingly driven by a hepatic bottleneck caused by gluconeogenesis-induced cataplerotic stress. Altered fuel consumption was observed in organs not directly involved in muscle contraction, including the pancreas and brown fat. Several futile cycles surprisingly persisted during exercise, despite their energy cost. In sum, we provide a comprehensive, integrated, holistic, and quantitative accounting of metabolism during exercise in an intact organism.
{"title":"Quantification of nutrient fluxes during acute exercise in mice","authors":"Jessie Axsom, Tara TeSlaa, Won Dong Lee, Qingwei Chu, Alexis Cowan, Marc R. Bornstein, Michael D. Neinast, Caroline R. Bartman, Megan C. Blair, Kristina Li, Chelsea Thorsheim, Joshua D. Rabinowitz, Zoltan Arany","doi":"10.1016/j.cmet.2024.09.010","DOIUrl":"https://doi.org/10.1016/j.cmet.2024.09.010","url":null,"abstract":"Despite the known metabolic benefits of exercise, an integrated metabolic understanding of exercise is lacking. Here, we use <em>in vivo</em> steady-state isotope-labeled infusions to quantify fuel flux and oxidation during exercise in fasted, fed, and exhausted female mice, revealing several novel findings. Exercise strongly promoted glucose fluxes from liver glycogen, lactate, and glycerol, distinct from humans. Several organs spared glucose, a process that broke down in exhausted mice despite concomitant hypoglycemia. Proteolysis increased markedly, also divergent from humans. Fatty acid oxidation dominated during fasted exercise. Ketone production and oxidation rose rapidly, seemingly driven by a hepatic bottleneck caused by gluconeogenesis-induced cataplerotic stress. Altered fuel consumption was observed in organs not directly involved in muscle contraction, including the pancreas and brown fat. Several futile cycles surprisingly persisted during exercise, despite their energy cost. In sum, we provide a comprehensive, integrated, holistic, and quantitative accounting of metabolism during exercise in an intact organism.","PeriodicalId":9840,"journal":{"name":"Cell metabolism","volume":null,"pages":null},"PeriodicalIF":29.0,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142436349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-15DOI: 10.1016/j.cmet.2024.09.011
Rui Li, Yan Li, Kun Jiang, Lijuan Zhang, Ting Li, Aihua Zhao, Zhuo Zhang, Yale Xia, Kun Ge, Yaqiong Chen, Chengnuo Wang, Weitao Tang, Shuning Liu, Xiaoxi Lin, Yuqin Song, Jie Mei, Chun Xiao, Aoxue Wang, Yejun Zou, Xie Li, Yuzheng Zhao
Arginine is one of the most metabolically versatile amino acids and plays pivotal roles in diverse biological and pathological processes; however, sensitive tracking of arginine dynamics in situ remains technically challenging. Here, we engineer high-performance fluorescent biosensors, denoted sensitive to arginine (STAR), to illuminate arginine metabolism in cells, mice, and clinical samples. Utilizing STAR, we demonstrate the effects of different amino acids in regulating intra- and extracellular arginine levels. STAR enabled live-cell monitoring of arginine fluctuations during macrophage activation, phagocytosis, efferocytosis, and senescence and revealed cellular senescence depending on arginine availability. Moreover, a simple and fast assay based on STAR revealed that serum arginine levels tended to increase with age, and the elevated serum arginine level is a potential indicator for discriminating the progression and severity of vitiligo. Collectively, our study provides important insights into the metabolic and functional roles of arginine, as well as its potential in diagnostic and therapeutic applications.
精氨酸是代谢能力最强的氨基酸之一,在多种生物和病理过程中发挥着关键作用;然而,原位灵敏跟踪精氨酸动态在技术上仍具有挑战性。在这里,我们设计了高性能的荧光生物传感器(对精氨酸敏感(STAR))来阐明细胞、小鼠和临床样本中的精氨酸代谢。利用 STAR,我们展示了不同氨基酸在调节细胞内和细胞外精氨酸水平方面的作用。STAR 能够活细胞监测巨噬细胞活化、吞噬、排泄和衰老过程中的精氨酸波动,并揭示了细胞衰老取决于精氨酸的可用性。此外,一种基于 STAR 的简单快速的检测方法显示,血清精氨酸水平随着年龄的增长呈上升趋势,而血清精氨酸水平的升高是判别白癜风进展和严重程度的一个潜在指标。总之,我们的研究为精氨酸的代谢和功能作用及其在诊断和治疗中的应用潜力提供了重要的见解。
{"title":"Lighting up arginine metabolism reveals its functional diversity in physiology and pathology","authors":"Rui Li, Yan Li, Kun Jiang, Lijuan Zhang, Ting Li, Aihua Zhao, Zhuo Zhang, Yale Xia, Kun Ge, Yaqiong Chen, Chengnuo Wang, Weitao Tang, Shuning Liu, Xiaoxi Lin, Yuqin Song, Jie Mei, Chun Xiao, Aoxue Wang, Yejun Zou, Xie Li, Yuzheng Zhao","doi":"10.1016/j.cmet.2024.09.011","DOIUrl":"https://doi.org/10.1016/j.cmet.2024.09.011","url":null,"abstract":"Arginine is one of the most metabolically versatile amino acids and plays pivotal roles in diverse biological and pathological processes; however, sensitive tracking of arginine dynamics <em>in situ</em> remains technically challenging. Here, we engineer high-performance fluorescent biosensors, denoted sensitive to arginine (STAR), to illuminate arginine metabolism in cells, mice, and clinical samples. Utilizing STAR, we demonstrate the effects of different amino acids in regulating intra- and extracellular arginine levels. STAR enabled live-cell monitoring of arginine fluctuations during macrophage activation, phagocytosis, efferocytosis, and senescence and revealed cellular senescence depending on arginine availability. Moreover, a simple and fast assay based on STAR revealed that serum arginine levels tended to increase with age, and the elevated serum arginine level is a potential indicator for discriminating the progression and severity of vitiligo. Collectively, our study provides important insights into the metabolic and functional roles of arginine, as well as its potential in diagnostic and therapeutic applications.","PeriodicalId":9840,"journal":{"name":"Cell metabolism","volume":null,"pages":null},"PeriodicalIF":29.0,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142436319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}