Regulation Of Cellular Metabolism Research Articles

Lipid Droplet Accumulation in Cancer: Targeting Lipophagy as a Therapeutic Strategy

Lipid droplets (LDs) are dynamic organelles involved in cellular lipid storage, trafficking, and metabolic regulation. Recent studies highlight their altered accumulation in various cancer types, correlating with tumorigenesis, progression, and metastasis. The accumulation of LDs in cancer cells contributes to oncogenic lipid metabolism, which promotes cell proliferation, resistance to apoptosis, and adaptation to tumor microenvironment stresses, including hypoxia and nutrient deprivation. Lipophagy, a specialized form of autophagy responsible for the selective degradation of LDs, has emerged as a potential target for cancer therapy due to its role in modulating cellular lipid reserves and maintaining energy balance. This review explores the molecular mechanisms underlying LD accumulation in cancer and the regulation of lipophagy, examining the implications of lipid storage modulation on cancer cell survival and metabolic adaptation. We also discuss therapeutic strategies aimed at targeting lipophagy pathways, such as inhibition of key lipophagic regulators and combination approaches with established chemotherapies, to improve cancer treatment efficacy. Understanding the intersection of lipid metabolism, LD biogenesis, and lipophagy may offer novel therapeutic avenues, providing more personalized and effective interventions for lipid-metabolism-driven cancers. Keywords: Lipid droplets; Lipophagy; Cancer metabolism; Autophagy; Lipid metabolism; Therapeutic targets in cancer; Lipid accumulation in tumors

Caseinolytic protease P (ClpP) is a c-di-GMP effector protein modulating motility, biofilm and virulence in Stenotrophomonas maltophilia

Cyclic di-GMP (c-di-GMP) is a crucial secondary messenger in bacterial cells, profoundly impacting various physiological and biochemical processes. Numerous studies showed that c-di-GMP regulates specific bacterial pathways by interacting with related effectors, and modulating their functions at the transcriptional or post-transcriptional levels. How c-di-GMP regulates bacterial global metabolism remains to be explored. In this study, we employed c-di-GMP pull-down assays in Stenotrophomonas maltophilia. We identified one target protein as caseinolytic protease P (ClpP), a highly conserved protease in both eukaryotic and prokaryotic cells, playing an essential role in global cellular metabolism regulation. We examined the binding site of c-di-GMP with ClpP and demonstrated that c-di-GMP enhances the peptidase activity of ClpP. Furthermore, ClpP is shown to play a vital regulatory role in bacterial motility and can activate bacterial motility in the presence of high c-di-GMP level. This research demonstrates that c-di-GMP mediates global regulation at the metabolic level via protein homeostasis. Additionally, it offers critical insights into the functional role of ClpP, which may inform the development of novel antimicrobial strategies.

Structure of Full-Length Src Kinase and Its Key Phosphorylated States: Molecular Dynamics Study.

Src kinase is one of the key regulators of cellular metabolism and is dysregulated in numerous diseases, including cancer, neurodegenerative diseases, and particularly Alzheimer's disease. Despite its therapeutic importance, its full-length structure has never been obtained before, as it contains an intrinsically disordered regulatory region, SH4UD. The SH4UD region is crucial for Src activation, functional dimerization, and regulation by other kinases. In this study, we used the replica exchange molecular dynamics approach with a hybrid temperature and Hamiltonian tempering to obtain the conformational ensemble of full-length Src kinase in its non-phosphorylated state and in the presence of its two key regulatory phosphorylations: pY419 and pY530. The representative structures and simulation trajectories of non-phosphorylated pY419 and pY530 Src are available in open access. We demonstrate that pY419 phosphorylation, which is associated with Src activation, enhances its motility, whereas inhibited pY530 Src preserves relatively compact conformation. This study also provides insights into how SH4UD contributes to Src substrate binding, dimerization, and autophosphorylation, highlighting the putative role of 14-RRR-16 in this process.

Mitochondrial Dysfunction: Effects and Therapeutic Implications in Cerebral Gliomas.

Gliomas are the most common primary brain tumors, representing approximately 28% of all central nervous system tumors. These tumors are characterized by rapid progression and show a median survival of approximately 18 months. The therapeutic options consist of surgical resection followed by radiotherapy and chemotherapy. Despite the multidisciplinary approach and the biomolecular role of targeted therapies, the median progression-free survival is approximately 6-8 months. The incomplete tumor compliance with treatment is due to several factors such as the presence of the blood-brain barrier, the numerous pathways involved in tumor transformation, and the presence of intra-tumoral mutations. Among these, the interaction between the mutations of genes involved in tumor bio-energetic metabolism and the functional response of the tumor has become the protagonist of numerous studies. In this scenario, the main role is played by mitochondria, cellular organelles delimited by a double membrane and containing their own DNA (mtDNA), which participates in numerous cellular processes such as the regulation of cellular metabolism, cellular proliferation, and apoptosis and is also the main source of cellular energy production. Therefore, it is understood that the mitochondrion, specifically its functional alteration, is a leading figure in tumor transformation, including brain tumors. The acquisition of mutations in the mitochondrial DNA of tumor cells and the subsequent identification of the so-called mitochondria-related genes (MRGs), both functional (mutation of Complex I) and structural (mutations of Complex III/IV), have been seen to play an important role in metabolic reprogramming with increased proliferation, resistance to apoptosis, and the progression of tumorigenesis. This demonstrates that these mitochondrial alterations could have a role not only in the intrinsic tumor biology but also in the extrinsic one associated with the therapeutic response. We aim to summarize the main mitochondrial dysfunction interactions present in gliomas and how they might impact prognosis.

Lactylation of Hdac1 regulated by Ldh prevents the pluripotent-to-2C state conversion

BackgroundCellular metabolism regulates the pluripotency of embryonic stem cells (ESCs). Yet, how metabolism regulates the transition among different pluripotent states remains elusive. It has been shown that protein lactylation, which uses lactate, a metabolic product of glycolysis, as a substrate, plays a critical role in various biological events. Here we focused on that glycolysis regulates the conversion between ESCs and 2-cell-like cells (2CLCs) through protein lactylation.MethodsRNA-seq revealed the activation of 2-cell (2C) genes by suppression of Ldh. Stable isotope labeling by amino acids in cell culture (SILAC) coupled with lactylated peptide enrichment and quantitative mass spectrometric analysis was carried out to investigate the mechanism how protein lactylation regulates the pluripotent-to-2C transition. And we focused on Hdac1. Lactylation of Hdac1 required for silencing 2C genes was proved by quantitative reverse-transcription PCR (qRT-PCR), immunofluorescence (IF), Western blot and chimeric embryos. Chromatin immunoprecipitation coupled with sequencing (ChIP-seq) and in vitro deacetylation assay confirmed lactylation of Hdac1 promoting its binding at 2C genes and enhancing its deacetylase activity, thereby facilitating the removal of H3K27ac and the silencing of 2C genes.ResultsWe found that inhibition or depletion of Ldha, the enzyme converting pyruvate to lactate, leads to the activation of 2C genes, as well as reduced global lactylation in ESCs. To investigate the mechanism how protein lactylation regulates the pluripotent-to-2C transition, quantitative lactylome analysis was performed, and 1716 lactylated proteins were identified. We then focused on Hdac1, a histone deacetylase involved in the silencing of 2C genes. Lactylation of Hdac1 promotes its binding at 2C genes and enhances its deacetylase activity, thus facilitating the removal of H3K27ac and the silencing of 2C genes.ConclusionsIn summary, our study reveals a mechanistic link between cellular metabolism and pluripotency regulation through protein lactylation. Our research is the first time to reveal that quantitative lactylome analysis in mouse ESCs. We found that lactylated Hdac1 promotes its binding at 2C genes and enhances its deacetylase activity, thus facilitating the removal of H3K27ac and the silencing of 2C genes.

Mitochondrial Mutations in Cardiovascular Diseases: Preliminary Findings.

Background/Objectives: Mitochondria are the main organelles for ATP synthesis able to produce energy for several different cellular activities. Cardiac cells require high amounts of energy and, thus, they contain a high number of mitochondria. Consequently, mitochondrial dysfunction in these cells is a crucial factor for the development of cardiovascular diseases. Mitochondria constitute central regulators of cellular metabolism and energy production, producing approximately 90% of the cells' energy needs in the form of ATP via oxidative phosphorylation. The mitochondria have their own circular, double-stranded DNA encoding 37 genes. Any mitochondrial DNA sequence anomaly may result in defective oxidative phosphorylation and lead to cardiac dysfunction. Methods: In this study, we investigated the potential association between mitochondrial DNA mutation and cardiovascular disease. Cardiac tissue and serum samples were collected from seven patients undergoing coronary artery bypass grafting. Total DNA was extracted from cardiac muscle tissue specimens and serum and each sample was subjected to polymerase chain reaction (PCR) to amplify the NADH dehydrogenase 1 (ND1) gene, which is part of the mitochondrial complex I enzyme complex and was screened for mutations. Results: We identified one patient with a homoplasmic A to G substitution mutation in cardiac tissue DNA and two patients with heteroplasmic A3397G mutation in serum DNA. Specifically, amplicon sequence analysis revealed a homoplasmic A3397G substitution in the ND1 gene in a tissue sample of the patient with ID number 1 and a heteroplasmic mutation in A3397G in serum samples of patients with ID numbers 3 and 6, respectively. The A to G substitution changes the amino acid from methionine (ATA) to valine (GTA) at position 31 of the ND1 gene. Conclusions: The detection of this novel mutation in patients with coronary artery disease may contribute to our understanding of the association between mitochondrial dysfunction and the disease, implying that mitochondria may be key players in the pathogenesis of cardiovascular diseases.

Overexpressed nicotinamide N‑methyltransferase in endometrial stromal cells induced by macrophages and estradiol contributes to cell proliferation in endometriosis

Endometriosis, an estrogen-dependent chronic inflammatory condition, afflicts reproductive-aged women. However, the underlying pathological mechanisms remain to be elucidated. Nicotinamide N-methyltransferase (NNMT) is a critical enzyme involved in cellular metabolism and methylation regulation. This study investigated the role of NNMT in endometriosis. By analyzing datasets GSE5108, GSE7305, GSE141549, GSE23339, and GSE25628, we identified a significant overexpression of NNMT in the eutopic endometrium and ectopic lesions of endometriosis patients compared to normal endometrium. Furthermore, NNMT was upregulated in collected endometrioma specimens and isolated primary endometrial stromal cells (ESCs) compared to their respective controls. Inhibition of NNMT using JBSNF-000088 attenuated the proliferation, migration, and invasion of ESCs. In vivo, treatment of mouse models of endometriosis with JBSNF-000088 resulted in a marked reduction in lesion weight and quantity. NNMT expression in ESCs was dose-dependently upregulated by 17β-estradiol at concentrations of 1 nM, 10 nM, and 100 nM, an effect that was attenuated by 10 nM progesterone. Additionally, treating HESCs with macrophage-conditioned medium elevated NNMT expression at both mRNA and protein levels. Knockdown of NNMT impeded the proliferation, migration, and invasion of ESCs, which was paralleled by decreased phosphorylation levels of Erb-b2 receptor tyrosine kinase 4 (ERBB4), PI3K, and AKT. Conversely, overexpressing ERBB4 mitigated the NNMT knockdown-induced decline in phosphorylated PI3K and AKT and rescued the proliferation of ESCs. Altogether, these results indicate that the overexpression of NNMT induced by estrogen and macrophage interaction modulates ESC proliferation via the NNMT-ERBB4-PI3K/AKT signaling pathway, as well as promotes cellular migration and invasion, contributing to the development of endometriosis.

Metabolic dysfunctions in type I myotonic dystrophy: A potential therapeutic target

Myotonic dystrophy type I (DM1) is a genetic disease characterized by a multisystemic RNA metabolism dysregulation and splicing toxicity. Numerous signaling pathways are deregulated, and especially AMPK, a key sensor and regulator of cellular metabolism. To restore AMPK signaling activity in DM1 muscle tissue and cells could improve mitochondrial biogenesis and dynamics, mitophagy and oxidative stress, energy production and, in fine, skeletal muscle tissue homeostasis.

Identifying the ceRNA Regulatory Network in Early-Stage Acute Pancreatitis and Investigating the Therapeutic Potential of NEAT1 in Mouse Models.

Acute pancreatitis (AP) is a common digestive disorder characterized by high morbidity and mortality. This study aims to uncover differentially expressed long noncoding RNAs (lncRNAs) and mRNAs, as well as related pathways, in the early stage of acute pancreatitis (AP), with a focus on the role of Neat1 in AP and severe acute pancreatitis (SAP). In this study, we performed high-throughput RNA sequencing on pancreatic tissue samples from three normal mice and three mice with cerulein-induced AP to describe and analyze the expression profiles of long non-coding RNAs (lncRNAs) and mRNAs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were conducted on the differentially expressed mRNAs to identify enriched pathways and biological processes. An lncRNA-miRNA-mRNA interaction network was constructed to elucidate potential regulatory mechanisms. Furthermore, we utilized Neat1 knockout mice to investigate the role of Neat1 in the pathogenesis of cerulein-AP and L-arginine-severe acute pancreatitis (SAP). Our results revealed that 261 lncRNAs and 1522 mRNAs were differentially expressed in the cerulein-AP group compared to the control group. GO and KEGG analyses of the differentially expressed mRNAs indicated that the functions of the corresponding genes are enriched in cellular metabolism, intercellular structure, and positive regulation of inflammation, which are closely related to the central events in the pathogenesis of AP. A ceRNA network involving 5 lncRNAs, 226 mRNAs, and 61 miRNAs were constructed. Neat1 was identified to have the potential therapeutic effects in AP. Neat1 knockout in mice inhibited pyroptosis in both the AP/SAP mouse models. We found that lncRNAs, particularly Neat1, play a significant role in the pathogenesis of AP. This finding may provide new insights into further exploring the pathogenesis of SAP and could lead to the identification of new targets for the treatment of AP and SAP.

Design, synthesis, and evaluation of some benzimidazole analogs as AMPK agonists

AMP-activated protein kinase is a crucial regulator of cellular metabolism with potential therapeutic implications in various diseases. In this study, the benzimidazole scaffold was chosen for investigation with EX-229 as the lead compound. Modifications were made to the terminal carboxyl group, and the methylindole moiety was replaced with phenylpyrrolidinone to synthesize and assess the AMP-activated protein kinase-activating properties of 13 benzimidazole derivatives. In vitro studies have shown that most of the synthesized compounds have significant excitatory effects on AMP-activated protein kinase. Particularly, A11 demonstrated the most potent activity with an EC50 value of 39 nM. Combining activity data and molecular docking analysis revealed the necessity of end-molecule hydrogen bond donors for LYS29, and the importance of an appropriate torsion angle at the pyrrolidinone position to facilitate the formation of a crucial hydrogen bond with LYS31. These discoveries offer preliminary insights into the interaction of small-molecule drugs with the AMP-activated protein kinase protein and establish a foundation for the future development of AMP-activated protein kinase activators guided by structure–activity relationships.

ATR promotes mTORC1 activity via de novo cholesterol synthesis.

DNA damage and cellular metabolism exhibit a complex interplay characterized by bidirectional feedback mechanisms. Key mediators of the DNA damage response and cellular metabolic regulation include Ataxia Telangiectasia and Rad3-related protein (ATR) and the mechanistic Target of Rapamycin Complex 1 (mTORC1), respectively. Previous studies have established ATR as a regulatory upstream factor of mTORC1 during replication stress; however, the precise mechanisms by which mTORC1 is activated in this context remain poorly defined. Additionally, the activity of this signaling axis in unperturbed cells has not been extensively investigated. Here, we demonstrate that ATR promotes mTORC1 activity across various cellular models under basal conditions. This effect is particularly enhanced in cells following the loss of p16, which we have previously associated with hyperactivation of mTORC1 signaling and here found have increased ATR activity. Mechanistically, we found that ATR promotes de novo cholesterol synthesis and mTORC1 activation through the upregulation of lanosterol synthase (LSS), independently of both CHK1 and the TSC complex. Furthermore, the attenuation of mTORC1 activity resulting from ATR inhibition was rescued by supplementation with lanosterol or cholesterol in multiple cellular contexts. This restoration corresponded with enhanced localization of mTOR to the lysosome. Collectively, our findings demonstrate a novel connection linking ATR and mTORC1 signaling through the modulation of cholesterol metabolism.

Mitochondria in tumor immune surveillance and tumor therapies targeting mitochondria.

Mitochondria play a central role in cellular energy production and metabolic regulation, and their function has been identified as a key factor influencing tumor immune responses. This review provides a comprehensive overview of the latest advancements in understanding the role of mitochondria in tumor immune surveillance, covering both innate and adaptive immune responses. Specifically, it outlines how mitochondria influence the function of the tumor immune system, underscoring their crucial role in modulating immune cell behavior to either promote or inhibit tumor development and progression. Additionally, this review highlights emerging drug interventions targeting mitochondria, including novel small molecules with significant potential in cancer therapy. Through an in-depth analysis, it explores how these innovative strategies could improve the efficacy and outlook of tumor treatment.

The effects of sodium-glucose cotransporter 2 inhibitors on the 'forgotten' right ventricle.

With the progress in diagnosis, treatment and imaging techniques, there is a growing recognition that impaired right ventricular (RV) function profoundly affects the prognosis of patients with heart failure (HF), irrespective of their left ventricular ejection fraction (LVEF). In addition, right HF (RHF) is a common complication associated with various diseases, including congenital heart disease, myocardial infarction (MI), pulmonary arterial hypertension (PAH) and dilated cardiomyopathy (DCM), and it can manifest at any time after left ventricular assist devices (LVADs). The sodium-glucose cotransporter 2 (SGLT2) inhibition by gliflozins has emerged as a cornerstone medicine for managing type 2 diabetes mellitus (T2DM) and HF, with an increasing focus on its potential to enhance RV function. In this review, we aim to present an updated perspective on the pleiotropic effects of gliflozins on the right ventricle and offer insights into the underlying mechanisms. We can ascertain their advantageous impact on the right ventricle by discussing the evidence obtained in animal models and monumental clinical trials. In light of the pathophysiological changes in RHF, we attempt to elucidate crucial mechanisms regarding their beneficial effects, including alleviation of RV overload, reduction of hyperinsulinaemia and inflammatory responses, regulation of nutrient signalling pathways and cellular energy metabolism, inhibition of oxidative stress and myocardial fibrosis, and maintenance of ion balance. Finally, this drug class's potential application and benefits in various clinical settings are described, along with a prospective outlook on future clinical practice and research directions.

Leveraging explainable deep learning methodologies to elucidate the biological underpinnings of Huntington’s disease using single-cell RNA sequencing data

BackgroundHuntington’s disease (HD) is a hereditary neurological disorder caused by mutations in HTT, leading to neuronal degeneration. Traditionally, HD is associated with the misfolding and aggregation of mutant huntingtin due to an extended polyglutamine domain encoded by an expanded CAG tract. However, recent research has also highlighted the role of global transcriptional dysregulation in HD pathology. However, understanding the intricate relationship between mRNA expression and HD at the cellular level remains challenging. Our study aimed to elucidate the underlying mechanisms of HD pathology using single-cell sequencing data.ResultsWe used single-cell RNA sequencing analysis to determine differential gene expression patterns between healthy and HD cells. HD cells were effectively modeled using a residual neural network (ResNet), which outperformed traditional and convolutional neural networks. Despite the efficacy of our approach, the F1 score for the test set was 96.53%. Using the SHapley Additive exPlanations (SHAP) algorithm, we identified genes influencing HD prediction and revealed their roles in HD pathobiology, such as in the regulation of cellular iron metabolism and mitochondrial function. SHAP analysis also revealed low-abundance genes that were overlooked by traditional differential expression analysis, emphasizing its effectiveness in identifying biologically relevant genes for distinguishing between healthy and HD cells. Overall, the integration of single-cell RNA sequencing data and deep learning models provides valuable insights into HD pathology.ConclusionWe developed the model capable of analyzing HD at single-cell transcriptomic level.

Recent Insights into Roles of Hypoxia-Inducible Factors in Retinal Diseases.

Hypoxia-inducible factors (HIFs) are transcriptional factors that function as strong regulators of oxygen homeostasis and cellular metabolisms. The maintenance of cellular oxygen levels is critical as either insufficient or excessive oxygen affects development and physiologic and pathologic conditions. In the eye, retinas have a high metabolic demand for oxygen. Retinal ischemia can cause visual impairment in various sight-threating disorders including age-related macular degeneration, diabetic retinopathy, and some types of glaucoma. Therefore, understanding the potential roles of HIFs in the retina is highly important for managing disease development and progression. This review focuses on the physiologic and pathologic roles of HIFs as regulators of oxygen homeostasis and cellular metabolism in the retina, drawing on recent evidence. Our summary will promote comprehensive approaches to targeting HIFs for therapeutic purposes in retinal diseases.

Aryl hydrocarbon receptor dynamics in esophageal squamous cell carcinoma: From immune modulation to therapeutic opportunities.

Esophageal squamous cell carcinoma (ESCC) is a substantial global health burden. Immune escape mechanisms are important in ESCC progression, enabling cancer cells to escape the surveillance of the host immune system. One key player in this process is the Aryl Hydrocarbon Receptor (AhR), which influences multiple cellular processes, including proliferation, differentiation, metabolism, and immune regulation. Dysregulated AhR signaling participates in ESCC development by stimulating carcinogenesis, epithelial-mesenchymal transition, and immune escape. Targeting AhR signaling is a potential therapeutic approach for ESCC, with AhR ligands showing efficacy in preclinical studies. Additionally, modification of AhR ligands and combination therapies present new opportunities for therapeutic intervention. This review aims to address the knowledge gap related to the role of AhR signaling in ESCC pathogenesis and immune escape.

Melatonin alleviates LPS-induced depression-like behavior in mice by inhibiting ferroptosis by regulating RNA methylation-mediated SIRT6/Nrf2/HO-1 pathway.

The objective of this study is to investigate the impact of ferroptosis on depression and elucidate the molecular mechanism underlying melatonin's inhibitory effect on ferroptosis in the treatment of depression. In this study, a depression-like behavior model was induced in mice using LPS, and the effect of melatonin on depression-like behavior was evaluated through behavioral experiments (such as forced swimming test (FST) and sucrose preference test (SPT)). Additionally, molecular biological techniques (including real-time fluorescence quantitative PCR, Western blotting, immunoprecipitation) were employed to detect the expression levels and interactions of METTL3, SIRT6 and ferroptosis-related genes in mouse brain tissue. Furthermore, both in vitro and in vivo experiments were conducted to verify the regulatory effect of melatonin on Nrf2/HO-1 pathway and explore its potential molecular mechanism for regulating ferroptosis. Melatonin was found to significantly ameliorate depression-like behavior in mice, as evidenced by reduced immobility time in the forced swimming test and increased sucrose intake in the sucrose preference test. Subsequent investigations revealed that melatonin modulated SIRT6 stability through METTL3-mediated ubiquitination of SIRT6, leading to its degradation. As a deacetylase, SIRT6 plays a pivotal role in cellular metabolism regulation and antioxidative stress response. This study elucidated potential signaling pathways involving Nrf2/HO-1 through which SIRT6 may exert its effects. The findings suggest that melatonin can improve depressive behavior by suppressing ferroptosis and protecting neurons through its antioxidant properties. Additionally, targeting the Nrf2/HO-1 pathway via METTL3 and NEDD4 regulation may be a potential therapeutic approach for depression.

Cell Death in Crustacean Immune Defense

ABSTRACTCell death mechanisms in crustaceans are a complex interplay of processes essential for maintaining cellular homeostasis and immune defense. Modes of cell death like apoptosis, necroptosis, and necrosis are well‐documented in crustaceans, serving crucial roles in removing damaged or infected cells. Unlike in other organisms, crustaceans likely lack pyroptosis, a type of programmed cell death associated with innate immunity and inflammation, because they do not possess the gasdermin genes essential for this process. Recently, NETosis and ferroptosis have emerged as significant mechanisms in pathogen defense. NETosis, involving the release of DNA fibers and antimicrobial proteins, helps trap and neutralize pathogens, while ferroptosis, an iron‐dependent form of cell death, contributes to lipid peroxidation and immune responses. Cuproptosis, although not yet studied in the context of crustacean immunity, shows potential crosstalk with ferroptosis, particularly in the regulation of metal ion homeostasis, oxidative stress, and cellular metabolism. Understanding these mechanisms offers promising applications in aquaculture, such as developing targeted immune modulators and enhancing disease resistance in economically important crustacean species.

Overview of carboxyl‑terminal modulator protein 1 and its importance in various metabolic regulations (Review).

Acyl‑coenzyme A thioesterases (ACOTs) are crucial in mediating lipid metabolic functions, including energy expenditure, hepatic gluconeogenesis and neuronal function. The two distinct types are type I and II ACOTs, the latter of which are 'hotdog' fold superfamily members. Type II ACOTs include carboxyl‑terminal modulator protein 1 (CTMP1), also termed thioesterase superfamily member 4 (THEM4), and CTMP2, also termed THEM5. Due to their similar structural features and distinct sequence homology, CTMP1 and CTMP2 stand out from other type II ACOTs. CTMP1 was initially known as a protein kinase B (PKB) inhibitor that attenuates PKB phosphorylation. PKB is the central regulator of various cellular functions, including survival, proliferation, growth and metabolism. Therefore, by inhibiting PKB, CTMP1 can affect various cellular processes. Various other functions of CTMP1 have been revealed, including functions in cancer, brain injury, mitochondrial function and lipid metabolism. CTMP2 is a paralog of CTMP1 and was first identified as a cardiolipin remodeling factor involved in the development of fatty liver. As the functions of CTMP1 and CTMP2 were discovered separately, a review to summarize and connect these findings is essential. The current review delineates the intricate complexity of CTMP regulation across different metabolic pathways and encapsulates the principal discoveries concerning CTMP until the present day.

Exosomes and Macrophages: Bidirectional Mutual Regulation in the Treatment of Diabetic Complications.

The bidirectional regulation of macrophages and exosomes provides a meaningful research direction for the treatment of complications arising from both type 1 and type 2 diabetes mellitus. However, there is currently no comprehensive evaluation of the bidirectional regulatory role of macrophages and exosomes in diabetic complications. In this review, we aim to provide the detailed process of the bidirectional regulation mechanism of macrophages and exosomes, and how macrophage-associated exosomes use this mechanism to make it better applied to clinical practice through biotechnology. Therefore, we summarized the bidirectional regulation mechanism of macrophages and exosomes and the application based on the bidirectional regulation mechanism from two aspects of inflammation and insulin resistance. As key regulators of the immune system, macrophages are crucial in the progression of diabetic complications due to their significant impact on the regulation of cellular metabolism, inflammation, and insulin sensitivity. Furthermore, exosomes, as innovative mediators of intercellular communication, transport miRNAs, proteins, and various bioactive molecules, influencing the occurrence and progression of diabetic complications through the regulation of inflammation and insulin resistance. The bidirectional regulation between macrophages and exosomes provides a promising pathway for the treatment of diabetic complications aimed at regulating the immune response and improving insulin sensitivity. Understanding the complexity of the interaction between macrophages and exosomes can advance the treatment of diabetic complications and drug development, and bringing more innovative and effective treatment strategies for diabetic complications.