激活Toll样受体2可以促进胃癌细胞中的OXPHOS和糖酵解

目的:调查TLR家族中哪种TLR受体的配体依赖性激活可引起胃癌细胞的代谢重编程。方法:通过实时荧光定量PCR(RT-qPCR)和蛋白质印迹(WB)在一组人GC细胞中测量TLR家族成员的表达。通过进行Seahorse生物能测定以及测量L-乳酸和活性氧(ROS)的产生,确定激动剂对不同TLR(TLR2、4、9)诱导的人GC细胞的代谢变化;通过RT-qPCR在被刺激的GC细胞中分析了涉及氧化磷酸化和糖酵解的基因的表达;通过Western印迹表征SOD2的表达。结果:由合成分子或全病原体抗原激活的TLR2信号传导增强了胃癌细胞中高表达TLR2的细胞株的糖酵解活性和线粒体呼吸,而配体诱导的TLR4和TLR9活化抑制了线粒体呼吸或细胞外酸化率。同时,涉及葡萄糖代谢和氧化还原系统调节的基因,例如HIF1A,PFKFB3和SOD2,在TLRs下游被上调。结论:由配体诱导的特定TLRs的激活介导了人类GC细胞中不同的代谢表型。TLR2是唯一同时促进OXPHOS和糖酵解的家族成员,这可能导致肿瘤进展。

Exposure to Electromagnetic Fields from Mobile Phones and Fructose consumption Coalesce to Perturb Metabolic Regulators AMPK/SIRT1-UCP2/FOXO1 in Growing Rats

Objective In this study,the combined effect of two stressors,namely,electromagnetic fields(EMFs)from mobile phones and fructose consumption,on hypothalamic and hepatic master metabolic regulators of the AMPK/SIRT1-UCP2/FOXO1 pathway were elucidated to delineate the underlying molecular mechanisms of insulin resistance.Methods Weaned Wistar rats(28 days old)were divided into 4 groups:Normal,Exposure Only(ExpO),Fructose Only(FruO),and Exposure and Fructose(EF).Each group was provided standard laboratory chow ad libitum for 8 weeks.Additionally,the control groups,namely,the Normal and FruO groups,had unrestricted access to drinking water and fructose solution(15%),respectively.Furthermore,the respective treatment groups,namely,the ExpO and EF groups,received EMF exposure(1,760 MHz,2 h/day x 8 weeks).In early adulthood,mitochondrial function,insulin receptor signaling,and oxidative stress signals in hypothalamic and hepatic tissues were assessed using western blotting and biochemical analysis.Result In the hypothalamic tissue of EF,SIRT1,FOXO 1,p-PI3K,p-AKT,ComplexⅢ,UCP2,MnSOD,and catalase expressions and OXPHOS and GSH activities were significantly decreased(P<0.05)compared to the Normal,ExpO,and FruO groups.In hepatic tissue of EF,the p-AMPKα,SIRT1,FOXO1,IRS1,p-PI3K,ComplexⅠ,Ⅱ,Ⅲ,Ⅳ,Ⅴ,UCP2,and MnSOD expressions and the activity of OXPHOS,SOD,catalase,and GSH were significantly reduced compared to the Normal group(P<0.05).Conclusion The findings suggest that the combination of EMF exposure and fructose consumption during childhood and adolescence in Wistar rats disrupts the closely interlinked and multi-regulated crosstalk of insulin receptor signals,mitochondrial OXPHOS,and the antioxidant defense system in the hypothalamus and liver.

线粒体DNA和疾病

人线粒体ＤＮＡ是含有１６５６９ｂｐ的闭环双链分子。它为１３种氧化磷酸作用酶的亚单位、结构ｒＲＮＡｓ和ｔＲＮＡｓ编码。近年来很多引起人类疾病的线粒体ＤＮＡ突变已被确定，如眼盲、耳聋、心力衰竭和人类退行性疾病等。线粒体ＤＮＡ疾病可能比先前想象的多。

ILF2 cooperates with E2F1 to maintain mitochondrial homeostasis and promote small cell lung cancer progression

Objective:Mitochondria play multifunctional roles in carcinogenesis.Deciphering uncertainties of molecular interactions within mitochondria will promote further understanding of cancer.Interleukin enhancer binding factor 2(ILF2)is upregulated in several malignancies,however,much remains unknown regarding ILF2 in small cell lung cancer(SCLC).In the current study,we explored ILF2's role in SCLC and demonstrated its importance in mitochondria quality control.Methods:Colony formation,cell proliferation,cell viability and xenograft studies were performed to examine ILF2's role on SCLC progression.Glucose uptake,lactate production,cellular oxygen consumption rate and extracellular acidification rate were measured to examine the effect of ILF2 on glucose metabolism.RNA-sequencing was utilized to explore genes regulated by ILF2.E2 F1 transcriptional activity was determined by dual luciferase reporter assay.Mitochondria quantification and mitochondrial membrane potential assays were performed to examine mitochondrial quality.Gene expression was determined by RT-qPCR,Western blot and IHC assay.Results:ILF2 promotes SCLC tumor growth in vitro and in vivo.ILF2 elevates oxidative phosphorylation expression and declines glucose intake and lactate production.Genome-wide analysis of ILF2 targets identified a cohort of genes regulated by E2 F1.In consistent with this,we found ILF2 interacts with E2 F1 in SCLC cells.Further studies demonstrated that suppression of E2 F1 expression could reverse ILF2-induced tumor growth and enhanced mitochondria function.Significantly,expression of ILF2 is progressively increased during SCLC progression and high ILF2 expression is correlated with higher histologic grades,which indicates ILF2's oncogenic role in SCLC.Conclusions:Our results demonstrate that ILF2 interacts with E2 F1 to maintain mitochondria quality and confers SCLC cells growth advantage in tumorigenesis.

The LncRNA FEZF1-AS1 promotes tumor proliferation in colon cancer by regulating the mitochondrial protein PCK2

LncRNAs and metabolism represents two factors involved in cancer initiation and progression.However,the interaction between lncRNAs and metabolism remains to be fully explored.In this study,lncRNA FEZF1-AS1(FEZF1-AS1)was found upregulated in colon cancer after screening all the lncRNAs of colon cancer tissues deposited in TCGA,the result of which was further confirmed by RNAscope staining on a colon tissue chip.The results obtained using FEZF1-AS1 knockout colon cancer cells(SW480 KO and HCT-116 KO)constructed using CRISPR/Cas9 system confirmed the proliferation,invasion,and migration-promoting function of FEZF1-AS1 in vitro.Mechanistically,FEZF1-AS1 associated with the mitochondrial protein phosphoenolpyruvate carboxykinase(PCK2),which plays an essential role in regulating energy metabolism in the mitochondria.Knockdown of FEZF1-AS1 greatly decreased PCK2 protein levels,broke the homeostasis of energy metabolism in the mitochondria,and inhibited proliferation,invasion,and migration of SW480 and HCT-116 cells.PCK2 overexpression in FEZF1-AS1 knockout cells partially rescued the tumor inhibitory effect on colon cancer cells both in vitro and in vivo.Moreover,PCK2 overexpression specifically rescued the abnormal accumulation of Flavin mononucleotide(FMN)and succinate,both of which play an important role in oxidative phosphorylation(OXPHOS).Overall,these results indicate that FEZF1-AS1 is an oncogene through regulating energy metabolism of the cell.This research reveals a new mechanism for lncRNAs to regulate colon cancer and provides a potential target for colon cancer diagnosis and treatment.

中药干预乳腺癌氧化磷酸化的研究进展

氧化磷酸化(OXPHOS)对肿瘤细胞的能量代谢起着重要的调节作用,近年来中药对其干预作用的研究越来越多。为更好地梳理中药对肿瘤细胞氧化磷酸化的影响,本文就近年来中药对乳腺癌氧化磷酸化代谢方式的干预研究进行综述。发现有19个中药成分可影响乳腺癌细胞的OXPHOS,涉及清热解毒、疏肝理气、活血化瘀、清热化湿等中药,其作用机理与调控线粒体复合物Ⅰ、Ⅱ活力,增加细胞内活性氧水平,调节AKT/mTOR、ERK/AKT、SIRT6/NF-κB等信号通路,从而影响线粒体功能有关。这些研究为未来中医药在该领域的研究提供了有益的探索,具有重要的参考价值。

Metabolism along the life journey of T cells

T cells are one of few cell types in adult mammals that can proliferate extensively and differentiate diversely upon stimulation,which serves as an excellent example to dissect the metabolic basis of cell fate decisions.During the last decade,there has been an explosion of research into the metabolic control of T-cell responses.The roles of common metabolic pathways,including glycolysis,lipid metabolism,and mitochondrial oxidative phosphorylation,in T-cell responses have been well characterized,and their mechanisms of action are starting to emerge.In this review,we present several considerations for T-cell metabolism-focused research,while providing an overview of the metabolic control of T-cell fate decisions during their life journey.We try to synthesize principles that explain the causal relationship between cellular metabolism and T-cell fate decision.We also discuss key unresolved questions and challenges in targeting T-cell metabolism to treat disease.

Targeting metabolic vulnerabilities to overcome resistance to therapy in acute myeloid leukemia

Malignant hematopoietic cells gain metabolic plasticity, reorganize anabolic mechanisms to improve anabolic output and prevent oxidative damage, and bypass cell cycle checkpoints, eventually outcompeting normal hematopoietic cells. Current therapeutic strategies of acute myeloid leukemia (AML) are based on prognostic stratification that includes mutation profile as the closest surrogate to disease biology. Clinical efficacy of targeted therapies, e.g., agents targeting mutant FMS-like tyrosine kinase 3 (FLT3) and isocitrate dehydrogenase 1 or 2, are mostly limited to the presence of relevant mutations. Recent studies have not only demonstrated that specific mutations in AML create metabolic vulnerabilities but also highlighted the efficacy of targeting metabolic vulnerabilities in combination with inhibitors of these mutations. Therefore, delineating the functional relationships between genetic stratification, metabolic dependencies, and response to specific inhibitors of these vulnerabilities is crucial for identifying more effective therapeutic regimens, understanding resistance mechanisms, and identifying early response markers, ultimately improving the likelihood of cure. In addition, metabolic changes occurring in the tumor microenvironment have also been reported as therapeutic targets. The metabolic profiles of leukemia stem cells (LSCs) differ, and relapsed/refractory LSCs switch to alternative metabolic pathways, fueling oxidative phosphorylation (OXPHOS), rendering them therapeutically resistant. In this review, we discuss the role of cancer metabolic pathways that contribute to the metabolic plasticity of AML and confer resistance to standard therapy;we also highlight the latest promising developments in the field in translating these important findings to the clinic and discuss the tumor microenvironment that supports metabolic plasticity and interplay with AML cells.

BaTiO_(3)@Au nanoheterostructure suppresses triple-negative breast cancer by persistently disrupting mitochondrial energy metabolism

Abnormal metabolism has become a potential target for highly malignant and invasive triple-negative breast cancer(TNBC)due to its relatively low response to traditional therapeutics.The existing metabolic interventions demonstrated unsatisfactory therapeutic outcomes and potential systemic toxicity,resulting from the metabolic instability and limited targeting ability of inhibitors as well as complex tumor microenvironment.To address these limitations,here we developed a robust pyroelectric BaTiO_(3)@Au core–shell nanostructure(BTO@Au)to selectively and persistently block energy generation of tumor cells.Stimulated by near-infrared(NIR)laser,the Au shell could generate heat to activate the BaTiO_(3)core to produce reactive oxygen species(ROS)regardless of the constrained microenvironment,thus prominently inhibits mitochondrial oxidative phosphorylation(OXPHOS)and reduces ATP production to induce TNBC cell apoptosis.The therapeutic effects have been well demonstrated in vitro and in vivo,paving a new way for the development of metabolic interventions.

HPDL deficiency causes a neuromuscular disease by impairing the mitochondrial respiration

Mitochondrial diseases are caused by variants in both mitochondrial and nuclear genomes.A nuclear gene HPDL(4-hydroxyphenylpyruvate dioxygenase-like),which encodes an intermembrane mitochondrial protein,has been recently implicated in causing a neurodegenerative disease characterized by pediatric-onset spastic movement phenotypes.Here,we report six Chinese patients with bi-allelic HPDL pathogenic variants from four unrelated families showing neuropathic symptoms of variable severity,including developmental delay/intellectual disability,spasm,and hypertonia.Seven different pathogenic variants are identified,of which five are novel.Both fibroblasts and immortalized lymphocytes derived from patients show impaired mitochondrial respiratory function,which is also observed in HPDL-knockdown(KD)He La cells.In these He La cells,overexpression of a wild-type HPDL gene can rescue the respiratory phenotype of oxygen consumption rate.In addition,a decreased activity of the oxidative phosphorylation(OXPHOS)complex II is observed in patient-derived lymphocytes and HPDL-KD He La cells,further supporting an essential role of HPDL in the mitochondrial respiratory chain.Collectively,our data expand the clinical and mutational spectra of this mitochondrial neuropathy and further delineate the possible disease mechanism involving the impairment of the OXPHOS complex II activity due to the bi-allelic inactivations of HPDL.

PGC-1α regulates the cell cycle through ATP and ROS in CH1 cells

Peroxisome proliferator-activated receptor-γ coactivator 1α（PGC-1α） is a transcriptional co-activator involved in mitochondrial biogenesis, respiratory capacity, and oxidative phosphorylation（OXPHOS）. PGC-1α plays an important role in cellular metabolism and is associated with tumorigenesis, suggesting an involvement in cell cycle progression. However, the underlying mechanisms mediating its involvement in these processes remain unclear. To elucidate the signaling pathways involved in PGC-1α function, we established a cell line, CH1 PGC-1α, which stably overexpresses PGC-1α. Using this cell line, we found that over-expression of PGC-1α stimulated extra adenosine triphosphate（ATP） and reduced reactive oxygen species（ROS） production. These effects were accompanied by up-regulation of the cell cycle checkpoint regulators Cyclin D1 and Cyclin B1. We hypothesized that ATP and ROS function as cellular signals to regulate cyclins and control cell cycle progression. Indeed, we found that reduction of ATP levels down-regulated Cyclin D1 but not Cyclin B1, whereas elevation of ROS levels down-regulated Cyclin B1 but not Cyclin D1. Furthermore, both low ATP levels and elevated ROS levels inhibited cell growth, but PGC-1α was maintained at a constant level. Together, these results demonstrate that PGC-1α regulates cell cycle progression through modulation of Cyclin D1 and Cyclin B1 by ATP and ROS. These findings suggest that PGC-1α potentially coordinates energy metabolism together with the cell cycle.

Zic1 negatively regulates brown adipogenesis in C_3H_(10)T_(1/2) cells

Zinc finger in the cerebellum 1 （Zicl） is known to regulate neurogenesis and myogenesis in the develop- mental stage and widely used as one of the brown adipocyte-specific markers. In this study, we examined the effect of Zicl on brown adipogenesis. Overexpression of Zicl attenuated the lipid accumulation and the expressions of PPAR72 and C/EBPα in C3H10T1/2 mesenchymal stem cells. The mRNA levels of BAT-specific thermogenic genes （PRDM16, PGC-1α and UCP1） and fatty acid oxidation regulatory genes （PPARα, CPT1α, CPT1β and COX7α1） were suppressed in Zicl-overexpressed cells. Moreover, overexpression of Zicl reduced the mitochondrial oxidative phosphorylation （OXPHOS） regulatory proteins including ATP5α, UQCRC2, SDHB and NDUFB5. These results indicate a potential role of Zicl in the regulation of brown adipogenesis via inhibiting adipogenesis, fatty acid oxidation and mitochondrial OXPHOS.