Hexokinase II integrates energy metabolism and cellular protection: Akting on mitochondria and TORCing to autophagy

Daurisoline inhibits glycolysis of lung cancer by targeting the AKT-HK2 axis

Lung cancer, one of the most prevalent tumors, remains a clinical challenge with a poor five-year survival rate. Daurisoline, a bis-benzylisoquinoline alkaloid derived from the traditional Chinese herb Menispermum dauricum, is known to suppress tumor growth effectively. However, its precise mechanism of action remains unclear. In this study, we demonstrate that Daurisoline targets glycolysis and reduces the protein level of HK2, thereby inhibiting lung cancer progression. Mechanistic investigations reveal that Daurisoline directly binds to AKT and antagonizes the AKT-GSK3β-c-Myc-HK2 signaling axis. Furthermore, in an animal model, we validate the in vivo anti-tumor effect of Daurisoline without any observable side effects. Overall, our findings suggest that Daurisoline holds potential as an anti-tumor agent through its targeting of glycolysis.

Therapeutic management of PI3Kα inhibitor-induced hyperglycemia with a novel glucokinase activator: Advancing the Frontier of PI3Kα inhibitor therapy

OBJECTIVES

The phosphatidylinositol 3-kinase (PI3K) signaling pathway is a pivotal target in cancer treatment, driving substantial investigation into PI3K inhibitors (PI3Ki). However, the common on-target adverse effect of hyperglycemia presents a substantial challenge to their clinical application. There is an urgent need to discover an anti-hyperglycemic agent that maintains the efficacy of PI3Ki.

METHODS

We conducted a comprehensive study to explore the interaction between exogenous hyperinsulinemia and PI3Ki in SKOV3 and OVCAR3 ovarian cancer cell lines. We used Western blotting, CCK-8, and EdU assays to determine the effect of this interaction on cell proliferation. In addition, we evaluated the anti-hyperglycemic effects of dorzagliatin in a PI3Ki-induced hyperglycemic mice model. Cell line-derived xenograft (CDX) models were employed to evaluate the in vivo tumor growth inhibitory effects of combining dorzagliatin with PI3Ki.

RESULTS

Western blot analysis demonstrated that insulin activated the AKT/INSR/mTOR pathway, reversing PI3Ki-induced p-AKT inhibition. Insulin also attenuated the anti-proliferative effects of PI3Ki. In the hyperglycemic mouse model, dorzagliatin significantly reduced blood glucose levels compared to controls. The combination therapy group (Dorzagliatin + PI3Ki) in CDX models showed a marked reduction in tumor volume. Dorzagliatin not only mitigated hyperglycemia but also enhanced the anti-tumor effects of PI3Ki. A clinical trial (NCT06117566) in cervical cancer patients supported these findings, showing that dorzagliatin stabilized blood glucose levels, facilitated body weight recovery, and achieved a confirmed partial response (PR).

CONCLUSIONS

Dorzagliatin shows promise for managing PI3Ki-associated hyperglycemia, thereby enhancing its therapeutic efficacy. The activation of liver glycogen kinase and insulin regulation may be key mechanisms underlying its therapeutic benefits.

miR-181a-5p mediates the effects of BMP4 on intestinal cell proliferation and differentiation

The intestinal mucosa undergoes a dynamic process of continual proliferation, differentiation, and apoptosis. Delineating the mechanisms involved in intestinal epithelial cell (IEC) differentiation is crucial to our understanding of not only normal gut adaptation but also aberrant intestinal growth. Bone morphogenetic protein (BMP) signaling is a pivotal regulator of intestinal proliferation and differentiation. However, the molecular underpinnings of the BMP pathway in this context are not entirely known. Here, we show a key role for the BMP4/microRNA (miR)-181/glycolysis signaling pathway in the maintenance of intestinal epithelial cell proliferation and differentiation. Treatment with BMP4 increased the expression of enterocyte markers and decreased proliferation of IECs, and importantly, decreased the expression of miR-181a-5p in mouse and human intestinal organoids. miR-181a-5p is a member of the miR-181 family with the highest expression in IECs. Treatment with locked nucleic acid (LNA) miR-181a-5p inhibitor significantly increased enterocyte differentiation as noted by increased expression of enterocyte markers in human and mouse intestinal organoids. In addition, LNA miR-181a-5p inhibitor repressed intestinal stem cell self-renewal as noted by the decreased organoid forming efficiency and expression of Ki67, cyclin D1, OLFM4 in human and mouse intestinal organoids. Moreover, in vivo administration of LNA miR-181a-5p inhibitor enhanced increased intestinal enterocyte differentiation and repressed intestinal cell proliferation. In contrast, overexpression of miR-181a-5p mimic decreased basal and BMP4-induced expression of enterocyte markers. Moreover, BMP4 treatment or inhibition of miR-181a-5p repressed hexokinase (HK) 1 expression and inhibited glycolysis. Consistently, knockdown of HK1 or inhibition of glycolysis using 2-deoxyglucose (2-DG) promoted enterocyte maturation and inhibited proliferation of IECs. Together, we provide evidence showing that miR-181a-5p inhibits intestinal enterocyte differentiation and promotes IEC proliferation through HK1-dependent glycolysis. Importantly, our findings identify miR-181a-5p as downstream in mediating BMP4 induction of enterocyte differentiation and inhibition of proliferation in IECs.

Targeting ncRNAs to overcome metabolic reprogramming‑mediated drug resistance in cancer (Review)

The emergence of resistance to antitumor drugs in cancer cells presents a notable obstacle in cancer therapy. Metabolic reprogramming is characterized by enhanced glycolysis, disrupted lipid metabolism, glutamine dependence and mitochondrial dysfunction. In addition to promoting tumor growth and metastasis, metabolic reprogramming mediates drug resistance through diverse molecular mechanisms, offering novel opportunities for therapeutic intervention. Non‑coding RNAs (ncRNAs), a diverse class of RNA molecules that lack protein‑coding function, represent a notable fraction of the human genome. Due to their distinct expression profiles and multifaceted roles in various cancers, ncRNAs have relevance in cancer pathophysiology. ncRNAs orchestrate metabolic abnormalities associated with drug resistance in cancer cells. The present review provides a comprehensive analysis of the mechanisms by which metabolic reprogramming drives drug resistance, with an emphasis on the regulatory roles of ncRNAs in glycolysis, lipid metabolism, mitochondrial dysfunction and glutamine metabolism. Furthermore, the present review aimed to discuss the potential of ncRNAs as biomarkers for predicting chemotherapy responses, as well as emerging strategies to target ncRNAs that modulate metabolism, particularly in the context of combination therapy with anti‑cancer drugs.

Inhibiting Glycolysis and Disrupting the Mitochondrial HK2-VDAC1 Protein-Protein Interaction Using a Bifunctional Lonidamine-Conjugated Metal Probe for Combating Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) relies primarily on aerobic glycolysis for energy and rapid cancer cell proliferation. Hexokinase 2 (HK2), a key enzyme regulating glycolysis, is overexpressed in TNBC, promoting tumor cell proliferation and apoptosis resistance by interacting with the mitochondrial membrane's voltage-dependent anion channel 1 (VDAC1). However, the development of bioactive molecules for effectively disrupting the HK2-VDAC1 interaction remains challenging. Herein, we have modified londamine (LND) with an iridium(III) complex to create bifunctional far-red probe 1. This complex not only has the ability to distinguish TNBC cells from normal cells by probing HK2 in mitochondria, but also significantly enhances antitumor activity by inhibiting mitochondrial glycolysis and effectively disrupting the HK2-VDAC1 interaction. This led to increased Bax-VDAC1 interaction, opening of the mitochondrial permeability transition pores (MPTPs), and generation of ROS, ultimately leading to mitochondrial dysfunction and enhanced cancer cell apoptosis. Probe 1 also demonstrated stronger antiproliferative activity than LND alone in a TNBC mouse model by targeting the HK2-VDAC1 interaction without causing overt toxicity. This work showcases the potential of probe 1 as an effective therapeutic agent for TNBC by inhibiting the mitochondrial HK2-VDAC1 interaction.

Flavonoids serve as a promising therapeutic agent for ischemic stroke

Ischemic stroke (IS) continues to be a major public health concern and is characterized by significantly high mortality and disabling rates. Inhibiting nerve cells death and enhancing the repair of ischemic tissue are important treatment concepts for IS. Currently, the mainstream treatment strategies mainly focus on short-term care, which underscores the urgent need for novel therapeutic strategies for long-term care. Emerging data reveal that flavonoids have surfaced as promising candidates for IS patients' long-term care. Flavonoids can alleviate neuroinflammation and anti-apoptosis due to their characteristic pharmacological mechanisms. Clinical evidence suggests that long-term flavonoids intake improves IS patients' long-term outcomes. Though the effect of flavonoids in IS treatment has been explored for decades, the neuroprotective pharmacodynamics have not been well established. Thereby, the aim of current review is to summarize the pathways involved in neuroprotective effect of flavonoids. This review will also advance the potential of flavonoids as a viable clinical candidate for the treatment of IS.

DEC1 Regulates Human β Cell Functional Maturation and Circadian Rhythm

Stem cell-derived islet (SC-islet) organoids offer hope for cell replacement therapy in diabetes, but their immature function remains a challenge. Mature islet function requires the β-cell circadian clock, yet how the clock regulates maturation is unclear. Here, we show that a circadian transcription factor specific to maturing SC-β cells, DEC1, regulates insulin responsiveness to glucose. SC-islet organoids form normally from DEC1 -ablated human pluripotent stem cells, but their insulin release capacity and glucose threshold fail to increase during in vitro culture and upon transplant. This deficit reflects downregulation of maturity-linked effectors of glucose utilization and insulin exocytosis, blunting glycolytic and oxidative metabolism, and is rescued by increasing metabolic flux. Moreover, DEC1 is needed to boost SC-islet maturity by synchronizing circadian glucose-responsive insulin secretion rhythms and clock machinery. Thus, DEC1 links circadian control to human β-cell maturation, highlighting its vitality to foster fully functional SC-islets.

Metabolic Adaptations and Therapies in Cardiac Hypoxia: Mechanisms and Clinical Implications/ Potential Strategies

Cardiac hypoxia triggers a cascade of responses and functional changes in myocardial and non-myocardial cells, profoundly affecting cellular metabolism, oxygen-sensing mechanisms, and immune responses. Myocardial cells, being the primary cell type in cardiac tissue, undergo significant alterations in energy metabolism, including glycolysis, fatty acid metabolism, ketone body utilization, and branched-chain amino acid metabolism, to maintain cardiac function under hypoxic conditions. Non-myocardial cells, such as fibroblasts, endothelial cells, and immune cells, although fewer in number, play crucial roles in regulating cardiac homeostasis, maintaining structural integrity, and responding to injury. This review discusses the metabolic reprogramming of immune cells, particularly macrophages, during ischemia-reperfusion injury and explores various therapeutic strategies that modulate these metabolic pathways to protect the heart during hypoxia. Understanding these interactions provides valuable insights and potential therapeutic targets for heart disease treatment.

Dynamin-Related Protein 1 Orchestrates Inflammatory Responses in Periodontal Macrophages via Interaction With Hexokinase 1

AIM

To explore the potential roles of mitochondrial dysfunction in the initiation of inflammation in periodontal macrophages and to determine the mechanism underlying the involvement of dynamin-related protein 1 (Drp1) in macrophage inflammatory responses through its interaction with hexokinase 1 (HK1).

MATERIALS AND METHODS

Gingival tissues were collected from patients diagnosed with periodontitis or from healthy volunteers. Drp1 tetramer formation and phosphorylation were analysed using western blot. THP-1 macrophages and RAW264.7 cells were stimulated with Porphyromonas gingivalis (Pg) or Pg lipopolysaccharide (Pg LPS), respectively. Alterations in proteins associated with mitochondrial dynamics were scrutinized via western blot. Immunofluorescence was used to evaluate mitochondrial damage and mitochondrial permeability transition pore (mPTP) opening. Western blot was used to examine the inflammatory markers NLRP3, caspase-1, IL-1β and GSDMD. Protein interactions involving Drp1 were verified through immunoprecipitation.

RESULTS

In periodontitis patient samples, Pg LPS-treated RAW264.7 cells, and Pg-stimulated THP-1 macrophages, over-activated Drp1 was able to drive NLRP3 inflammasome activation and the subsequent release of inflammatory factors. A direct interaction between Drp1 and HK1 was observed, facilitating excessive mPTP opening and subsequent mitochondrial dysfunction.

CONCLUSION

In the inflammatory milieu of periodontal tissues, Drp1 hyperactivation in the macrophages is implicated in inflammation induction. Modulation of the inflammatory response in periodontal macrophages by Drp1 appears to facilitate mPTP opening.

Antibiotic-derived approaches in cancer therapy: effectiveness of ikarugamycin in hexokinase-2 inhibition, tissue factor modulation, and metabolic regulation in breast cancer

We aimed to explore the role of ikarugamycin (IKA) in breast cancer, its connection with hexokinase-2 (HK-2) repression, and tissue factor (TF). This study sought to extend the role of HK-2 as a TF activator in a comprehensive analysis of these interactions from the enzyme, gene, and protein levels. The investigation was performed with MDA-MB-231 and MCF-7 breast cancer lines. The oxidative stress index (OSI), lactate production, and HK activity were assessed using colorimetric assays. Western blot and quantitative PCR analyses were performed to determine HK-2 and TF expressions. Prothrombin time Tests additionally assessed the effect of IKA therapy on TF activation. Three over four significantly downregulated genes were identified after a specific analysis of the IKA's effect on HK-2 and TF in breast cancer cell lines. In the IKA treatment group, lactate production was markedly reduced ( P  < 0.05) and hexokinase activity was found to be reduced in all groups ( P  < 0.05, <0.01). Paclitaxel cytotoxicity independently causes lower OSI in all IKA-treated groups as compared to controls even though OSI is elevated in IKA groups compared to control. Molecular analysis results demonstrated significantly downregulated HK-2 and TF expressions at the protein level ( P  < 0.05, P  < 0.01). Partial thromboplastin time results also showed that IKA-treated cells had longer TF activation duration. A potential indirect association of HK-2 inhibition and TF regulation in breast cancer cells is put forward in this study by presenting IKA's bioactivation of breast cancer in all gene, protein, and enzyme levels.

Oxidative stress regulates the catalytic activity and mitochondrial localization of HK2 in trophoblast by regulating K346 lactylation

Preeclampsia (PE) is one of the most dangerous complications of pregnancy. The pathogenic mechanisms of this condition are not yet clear. Lysine lactylation (Kla) is a novel post-translational modification (PTM) reported recently. It remains to be determined whether Kla plays a role in the development of PE. Here, western blotting revealed that the placental Kla profile of PE was different from that of normal pregnancies, and hydrogen peroxide (H2O2) weakened the Kla level of trophoblast cells. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) indicated that 333 Kla sites of 232 proteins were changed by Kla in BeWo cells (a trophoblast cell line) treated with H2O2, among which only HK2 showed a unique Kla site (K346) with down-regulated lactylation. Additionally, the inactive mutant HK2-K346 was associated with decreased hexokinase activity, lower affinity to voltage-dependent anion channel 1 (VDAC1), and impaired cell proliferation. These findings demonstrate that lactylation is involved in the pathogenesis of PE and that lactylation of HK2-K346 could serve as a new connection between oxidative stress, energy metabolism, and the development of PE.

Aldose reductase, fructose and fat production in the liver

There is an increasing interest in the role of fructose as a major driver of non-alcoholic fatty liver disease (NAFLD), and it is linked closely with the intake of sugar. However, there has also been the recognition that fructose can be produced directly from intracellular glucose via the evolutionarily conserved polyol pathway whose access is governed by aldose reductase (AR). The purpose of this article is to review the biochemistry of AR and the role of the polyol pathway in opening fructose metabolism. This article provides a new perspective about AR and the other key enzymes surrounding the decision to divert glucose into the polyol pathway which suggests that the production of endogenous fructose may be of much greater significance than historically viewed. There are important aspects of the regulation of the polyol pathway and its committal step catalyzed by AR, which supports the notion that fructose-uric acid pathway is activated by elevated glucose with the downstream consequence of NAFLD and perhaps other chronic metabolic diseases.

Study on the mechanism of 17-Hydroxy-jolkinolide B on anaplastic thyroid cancer cell

BACKGROUND

Anaplastic thyroid cancer (ATC) has a dismal prognosis, and the optimal treatment has not yet been confirmed. Euphorbia fischeriana Steud has been proven to exhibit pharmacological properties, including various antitumor effects, that can be used to treat numerous diseases and has been used to treat cancer. 17-Hydroxy-jolkinolide B (17-HJB) is one of the major diterpenoids produced from plants, but little research has investigated how it affects cancer.

METHODS

MTT assays, glucose and lactate concentration detection, Annexin V-FITC detection via cytometry, and Western blotting were performed to research the mechanism of 17-HJB.

RESULTS

Cell viability was inhibited in a concentration-dependent manner after 17-HJB treatment. 17-HJB inhibited glucose consumption and lactate production, and the expression of the glucose transporter GLUT1 and proteins associated with glycolysis, HK2, PFK1, and PKM2, was significantly downregulated. 17-HJB induced apoptosis, and the expression of signaling proteins related to apoptosis, such as Caspase-3 and cleaved Caspase-3, was upregulated. In vivo, 17-HJB effectively inhibited the growth of ATC tumors. The results of the expression of glycolysis-related enzyme proteins and apoptosis signaling proteins were consistent with those in vitro.

CONCLUSIONS

17-HJB inhibited the growth of ATCs both in vivo and in vitro. The mechanism may be related to the effects on glucose metabolism and the inhibition of aerobic glycolysis. 17-HJB also induced ATC apoptosis.

Regulation of anaplerotic enzymes by melatonin enhances resilience to cadmium toxicity in Vigna radiata (L.) R. Wilczek

Melatonin (Mel) is a tryptophan-derived (N-acetyl-5-methoxytryptamine) molecule. In the present study, role of Mel in the regulation of various anaplerotic enzymes is discussed in relation to N metabolism and H+-ATPase activity in mung bean under Cd stress. The application of Mel to the Cd-stressed mung bean seedlings was remarkable in improving the activity of hexokinase (35.7%), pyruvate kinase (79.2%), phosphoenolpyruvate carboxylase (38.9%) pyruvate dehydrogenase (41.5%), malate dehydrogenase (49.2%), citrate synthase (37.7%), isocitrate dehydrogenase (33.1%), ATP synthase (63.6%), and ATPase (38.6%). Incubation of Cd-stressed seedlings with Mel also improved the activity of nitrate reductase by 89.4%, nitrite reductase by 78.2%, and glutamine synthetase by 35.3% that resulted in higher level of ammonium and their subsequent assimilation to amino acids and proteins. Activation of these enzymes was strongly associated with Mel-induced regulation of H+-ATPase activity that improved K+ retention and N assimilation capacity of the Cd-stressed seedlings of mung bean. The coordinated mechanism of action of tricarboxylic acid (TCA) cycle, N metabolism, and higher K+ levels were helpful in providing protection against detrimental effects of Cd toxicity through improving the defense system and energy level of the plants. However, inclusion of sodium orthovanadate (PM H+-ATPase inhibitor) to the incubation medium reversed the positive effect of Mel and suppressed the performance of plants under Cd-stress. The findings of the study indicate that under Cd stress, the regulatory mechanisms of anaplerotic enzymes and antioxidant defense are mediated by Mel, and this process is facilitated by the retention of K+ induced by H+-ATPase.

Alpha-ketoglutarate promotes anxiety, activates autophagy, and suppresses antioxidant enzymes in the cerebral cortex of female mice on cafeteria diet

Alpha-ketoglutarate (AKG), an intermediate of the tricarboxylic acid cycle, has been found to mitigate oxidative stress and inflammation. In turn, a cafeteria diet (CD), an obesogenic diet, is often associated with oxidative stress and inflammation. This study aimed to determine whether AKG can level the effects of CD on animal behavior, oxidative stress markers, glycolytic flow, and autophagy in the mouse cerebral cortex. Female C57BL/6 J mice were divided into two groups and fed either a standard diet or a CD for eight weeks. For the next four weeks, each group continued to be fed the previous diet; however, half of the individuals within each group received drinking water with 1 % AKG. Using an open field test, we found that the combination of CD and AKG promoted the development of anxiety signs. Both CD and AKG decreased the exploratory behavior of mice, with a significant additive effect in the combined diet. On diets supplemented with AKG, animals produced fewer fecal boli, a measure of emotionality. On all experimental diets, mice had lower activities of antioxidant and related enzymes, with no significant differences in the activities of glycolytic enzymes. The AKG-supplemented diet induced the transcription of autophagy-related genes and targets of the forkhead box O factor, involved in the regulation of carbohydrate metabolism. Transcriptional changes induced by AKG were partly abrogated by the CD. These findings suggest that AKG, particularly when combined with CD, may modulate behavioral responses and oxidative stress intensity in the brain by altering key metabolic and autophagic pathways.

Exploring glycolytic enzymes in disease: potential biomarkers and therapeutic targets in neurodegeneration, cancer and parasitic infections

Glycolysis, present in most organisms, is evolutionarily one of the oldest metabolic pathways. It has great relevance at a physiological level because it is responsible for generating ATP in the cell through the conversion of glucose into pyruvate and reducing nicotinamide adenine dinucleotide (NADH) (that may be fed into the electron chain in the mitochondria to produce additional ATP by oxidative phosphorylation), as well as for producing intermediates that can serve as substrates for other metabolic processes. Glycolysis takes place through 10 consecutive chemical reactions, each of which is catalysed by a specific enzyme. Although energy transduction by glucose metabolism is the main function of this pathway, involvement in virulence, growth, pathogen-host interactions, immunomodulation and adaptation to environmental conditions are other functions attributed to this metabolic pathway. In humans, where glycolysis occurs mainly in the cytosol, the mislocalization of some glycolytic enzymes in various other subcellular locations, as well as alterations in their expression and regulation, has been associated with the development and progression of various diseases. In this review, we describe the role of glycolytic enzymes in the pathogenesis of diseases of clinical interest. In addition, the potential role of these enzymes as targets for drug development and their potential for use as diagnostic and prognostic markers of some pathologies are also discussed.

The impact of glycolysis on ischemic stroke: from molecular mechanisms to clinical applications

Ischemic stroke (IS), a leading cause of disability and mortality worldwide, remains a significant challenge due to its complex pathogenesis. Glycolysis, a central metabolic pathway, plays a critical role in bridging the gap between metabolic dysfunction and neurological impairment. During ischemic conditions, glycolysis replaces oxidative phosphorylation as the primary energy source for brain tissue. However, in the ischemia-reperfusion state, neuronal cells show a particular reliance on aerobic glycolysis. Immune cells, such as monocytes, also contribute to atheromatous plaque formation and thrombi through increased aerobic glycolysis. Given glycolysis's involvement in various pathological stages of IS, it offers the potential for improved diagnosis, treatment, and prevention. This review comprehensively explores the role of glycolysis in different phases of IS, addresses existing controversies, and discusses its diagnostic and therapeutic applications. By elucidating the intricate relationship between glycolysis and IS, this review aims to provide novel insights for future research and clinical advancements.

The Role of HK2 in Tumorigenesis and Development: Potential for Targeted Therapy with Natural Products

Hexokinase 2 (HK2) is widely distributed in various tissues, particularly showing significantly elevated expression levels in tumor tissues. As the initial rate-limiting enzyme in the glycolysis process, HK2 is believed to directly participate in the metabolic reprogramming of tumor cells. This phenomenon, known as the "Warburg effect," provides the energy and substances necessary for the rapid proliferation, growth, and division of tumor cells. Furthermore, by enhancing glycolysis, HK2 exerts its influence on various metabolic pathways in tumor cells, such as pentose phosphate metabolism, glutamine metabolism, serine metabolism, and glycine metabolism, thereby playing a role in the occurrence and development of cancer. Therefore, HK2 represents a promising target for cancer therapy. Simultaneously, natural products with effects on inhibiting the expression or activity of HK2, have already been discovered to exhibit significant anticancer potential. Flavonoids, pentacyclic triterpenoids, phenolic compounds, and lignans constitute the majority of these natural products, directly inhibiting HK2 or indirectly downregulating it through protein kinase B (AKT), hypoxia-inducible factor 1 alpha (HIF-1α), and c-Myc signaling pathways. However, several challenges remain, such as further screening for natural products that directly target and inhibit HK2, optimizing the selection of natural product inhibitors for HK2, and elucidating the molecular mechanisms by which natural products indirectly inhibit HK2. In conclusion, the potential of targeting HK2 for cancer therapy is promising, and with these challenges addressed, natural products inhibiting HK2 will play an even greater role in the fight against cancer.

Up-regulated ITGB4 promotes hepatocellular carcinoma metastasis by activating hypoxia-mediated glycolysis and cancer-associated fibroblasts

The pre-metastatic niche constructed by cancer-associated fibroblasts (CAFs) plays a key role in the hypoxic tumor microenvironment (TME), promoting hepatocellular carcinoma (HCC) metastasis. Integrin, which is involved in cell-to-cell or cell-to-matrix interactions and TME regulation, affects tumor metastasis. However, the complex interactions between integrin-mediated HCC cells and CAFs remain unclear. Co-culture experiments were used to assess the behaviors of HCC cells and CAFs, demonstrating HCC metastatic traits and CAFs activation in vitro. Transcriptome sequencing analysis and molecular detection identified key genes, with overexpression and knockdown experiments further confirming their roles in HCC progression. Xenograft models validated these findings in vivo. We showed that HCC cells induced the conversion of normal hepatic stellate cells (HSCs) into CAFs and recruit additional CAFs, driven by lactate produced by HCC. Integrin beta 4 (ITGB4) was identified as a key gene in the process. Inhibiting ITGB4 reduced lactate secretion, reversed CAFs activation and recruitment, and decreased HCC metastasis, while overexpressing ITGB4 significantly enhanced these malignant phenotypes. ITGB4 influences glycolysis and HCC metastasis through the AKT/HK2 signaling pathway, and CAFs activation and recruitment through the TGF-β/Smads signaling pathway. Compared to tumors derived from control cells, ITGB4-knockdown tumors showed fewer and smaller intrahepatic metastatic nodules, reduced lactate production and CAFs formation, along with inhibition of AKT/HK2 and TGF-β/Smads signaling pathways. Our findings highlighted the impact of hypoxia on HCC progression, revealing the roles of ITGB4-mediated glycolysis and lactate-induced CAFs in the pre-metastatic niche on HCC metastasis.

ROCK Inhibitor Enhances Resilience Against Metabolic Stress Through Increasing Bioenergetic Capacity in Corneal Endothelial Cells

Purpose

To investigate the effect of Rho-associated protein kinase (ROCK) inhibitor Y27632 on bioenergetic capacity and resilience of corneal endothelial cells (CECs) under metabolic stress.

Methods

Bovine CECs (BCECs) were treated with Y27632 and subjected to bioenergetic profiling using the Seahorse XFp Analyzer. The effects on adenosine triphosphate (ATP) production through oxidative phosphorylation and glycolysis were measured. BCECs were also challenged with monensin to induce metabolic stress. Cell viability, apoptosis, intracellular sodium levels, and hexokinase localization were assessed using calcein AM assay, flow cytometry, fluorescence imaging, and immunostaining, respectively.

Results

Y27632 increased maximal ATP production rates via both oxidative phosphorylation and glycolysis, thereby expanding the overall bioenergetic capacity in BCECs. Under monensin-induced metabolic stress, ROCK inhibitor pretreatment significantly enhanced glycolytic ATP production and reduced apoptosis compared with untreated cells. Y27632 also facilitated sodium export by increasing Na/K-ATPase activity, as evidenced by lower intracellular sodium levels. Additionally, Y27632 promoted the translocation of hexokinase 2 to mitochondria under stress conditions, thereby enhancing glycolytic capacity. The effect of Y27632 on cell viability and sodium export was abrogated when cells were forced to rely on oxidative phosphorylation in galactose media, indicating that the protective effects of Y27632 are dependent on glycolytic ATP production under monensin stress.

Conclusions

ROCK inhibitor Y27632 enhances the bioenergetic capacity of BCECs, allowing the cells to better withstand metabolic stress by rapidly generating ATP to meet increased energy demands, maintaining ion homeostasis and reducing apoptosis.

Distinct dynamic regulation of pectoralis muscle metabolomics by insulin and the promotion of glucose-lipid metabolism with extended duration

Birds' glycolipid metabolism has garnered considerable attention due to their fasting blood glucose levels being nearly twice those of mammals. While skeletal muscle is the primary insulin-sensitive tissue in mammals, the effects of insulin on chicken skeletal muscle remain unclear. In this study, the insulin-responsive metabolites were identified in broiler's pectoralis muscle (after 16 h of fasting) using widely targeted metabolomics. Glycolipid concentrations were measured using kits, and the expression of key genes involved in glucose metabolism was assessed via quantitative real-time PCR (qRT-PCR). The insulin tolerance test, performed by injecting 5 IU/kg body weight of insulin, demonstrated a rapid drop in blood glucose levels from 0 to 15 min, with a consistent reduction observed at 120 min (P < 0.01). Insulin did not alter glucose and glycogen content in chicken pectoralis; however, low-density lipoprotein (LDL, P < 0.05) levels were upregulated in the early phase (15 min). With an extended insulin duration (120 min), pectoralis glucose content increased (P < 0.05), accompanied by a reduction in TG levels (P < 0.05). Metabolomic analysis revealed that insulin promotes the downregulation of 63 out of 71 metabolites at 15 min and the upregulation of 101 out of 134 metabolites at 120 min, mainly associated with lysine degradation and thyroid hormone signaling pathways, respectively. 7 metabolites were dynamically modulated in the same manner over time (2 up-up and 5 down-down). Early insulin inhibited glycolysis, evidenced by the reduction in phosphoenolpyruvate levels and hexokinase 2 (HK2) expression; however, insulin promoted glucose uptake through the activation of glucose transporter 4 (GLUT4) and enhanced glycolysis, accompanied by elevated fatty acid metabolism at the later phase. In conclusion, insulin dynamically regulates the metabolomics of the pectoralis muscle over time. Initially, chicken muscle tissues downregulate metabolic activities to accommodate the new signaling state, followed by significant upregulation to meet heightened metabolic demands. Extended insulin monitoring promotes glucose uptake and glycolysis, alongside enhanced fatty acid metabolism. This research provides insights into the potential mechanisms of insulin action in chicken muscles.

Metabolic Reprogramming in Cancer: Implications for Immunosuppressive Microenvironment

Cancer is a complex and heterogeneous disease characterised by uncontrolled cell growth and proliferation. One hallmark of cancer cells is their ability to undergo metabolic reprogramming, which allows them to sustain their rapid growth and survival. This metabolic reprogramming creates an immunosuppressive microenvironment that facilitates tumour progression and evasion of the immune system. In this article, we review the mechanisms underlying metabolic reprogramming in cancer cells and discuss how these metabolic alterations contribute to the establishment of an immunosuppressive microenvironment. We also explore potential therapeutic strategies targeting metabolic vulnerabilities in cancer cells to enhance immune-mediated anti-tumour responses. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02044861, NCT03163667, NCT04265534, NCT02071927, NCT02903914, NCT03314935, NCT03361228, NCT03048500, NCT03311308, NCT03800602, NCT04414540, NCT02771626, NCT03994744, NCT03229278, NCT04899921.

Sirtuin1 (sirt1) regulates the glycolysis pathway and decreases cisplatin chemotherapeutic sensitivity to esophageal squamous cell carcinoma

We aimed to evaluate the influence of sirtuin1 (sirt1) on the ESCC chemotherapeutic sensitivity to cisplatin. We used ESCC cell ablation sirt1 for establishing a xenograft mouse tumor model. The tumor volume was then detected. sirt1 was over-expressed significantly in ESCC patients and cells. Moreover, sirt1 knockdown raised ESCC sensitivity to cisplatin. Besides, glycolysis was associated with ESCC cell chemotherapy resistance to cisplatin. Furthermore, sirt1 increased ESCC cells' cisplatin chemosensitivity through HK2. Sirt1 enhanced in vivo ESCC chemosensitivity to cisplatin. Overall, these findings suggested that sirt1 knockdown regulated the glycolysis pathway and raised the ESCC chemotherapeutic sensitivity.

Molecular and Clinical Characterization of a Founder Mutation Causing G6PC3 Deficiency

G6PC3 deficiency is a monogenic immunometabolic disorder that causes severe congenital neutropenia type 4. Patients display heterogeneous extra-hematological manifestations, contributing to delayed diagnosis. Here, we investigated the origin and functional consequence of the G6PC3 c.210delC variant found in patients of Mexican descent. Based on the shared haplotypes amongst mutation carriers, we estimated that this variant originated from a founder effect in a common ancestor. Furthermore, by ancestry analysis, we concluded that it appeared in the indigenous Mexican population. At the protein level, we showed that this frameshift mutation leads to an aberrant protein expression in overexpression and patient-derived Epstein-Barr Virus-immortalized B (EBV-B) cells. The neutropenia observed in G6PC3-deficient patients is driven by the intracellular accumulation of the metabolite 1,5-anhydroglucitol-6-phosphate (1,5-AG6P) that inhibits glycolysis. We characterized how the c.210delC variant impacts glycolysis by performing extracellular flux assays on patient-derived EBV-B cells. When treated with 1,5-anhydroglucitol (1,5-AG), the precursor to 1,5-AG6P, patient cells exhibited markedly reduced engagement of glycolysis. Finally, we compared the clinical presentation of patients with the mutation c.210delC and all other G6PC3-deficient patients reported in the literature, and we found that the c.210delC carriers display all prominent clinical features observed in prior patients. In conclusion, G6PC3 c.210delC is a loss-of-function mutation that arose from a founder effect in the indigenous Mexican population. These findings may facilitate the diagnosis of additional patients in this geographical area. Moreover, the in vitro 1,5-AG-dependent functional assay used in our study could be employed to assess the pathogenicity of additional G6PC3 variants.

STING regulates aging-related osteoporosis by mediating the Hk2-Vdac1 mitochondrial axis

Metabolic abnormalities and mild inflammation are hallmarks of aging and major driving factors for aging-related damage and bone metabolic diseases. Mitochondria are crucial links in energy metabolism and immune homeostasis regulation. Mitochondrial dysfunction is considered one of the pathogenic factors of aging-related osteoporosis, but its mechanism of action needs further research. Here, we demonstrated that the interaction between stimulator of interferon genes (STING)-mediated regulation of hexokinase 2 (Hk2)-voltage-dependent anion channel-1 (Vdac1) is a critical factor contributing to mitochondrial dysfunction and osteogenic abnormalities during aging. As the aging process progresses, factors related to aging cause an increase in STING expression, which disrupts the interaction between Hk2 and Vdac1. Dissociation of Hk2 from Vadc1 triggered the opening of the mitochondrial inner mitochondrial permeability transition pore (mPTP), leading to mitochondrial dysfunction and abnormal osteogenic differentiation, thereby disrupting bone homeostasis. In brief, this study demonstrates that STING acts as an intracellular metabolic Checkpoint, influencing mitochondrial function to promote the development of osteoporosis. These findings significantly enhance the development of STING-targeted treatments for aging-related osteoporosis.

African walnut (Plukenetia conophora) oil promotes glucose uptake while improving energy metabolism and steroidogenesis and maintaining surface architecture in rat testes

Background

African walnut (Plukenetia conophora) oil (AWO) has been reported for its nutritional and medicinal properties and has been employed for the management of metabolic diseases including hyperglycemia-mediated ailments.

Objective

In the present study, AWO was investigated for its ability to stimulate glucose uptake and its effect on energy metabolism, steroidogenesis, and tissue morphology in isolated testes of Wistar rats.

Methods

Isolated testes were incubated with AWO (30-240 μg/mL) in the presence of 11.1 mMol glucose at 37°C for 2 h. Control consisted of testes incubated with glucose only, while normal control consisted of testes not incubated with AWO and/or glucose. The standard antidiabetic drug was metformin.

Results and conclusion

Incubation with AWO led to significant increase in glucose uptake, hexokinase, glyoxalase 1, glutathione reductase, glutathione peroxidase, 3β-hydroxysteroid dehydrogenase, 17β-hydroxysteroid dehydrogenase activities, GLUT4, glutathione, and ATP levels while concomitantly suppressing glucose-6-phosphatase, fructose-1,6-biphosphatase, glycogen phosphorylase, aldose reductase, polyol dehydrogenase, E-NTPDase, and ATPase activities. Furthermore, incubation with AWO led to improved testicular morphology while elevating testicular levels of magnesium, sulfur, potassium, calcium, and iron. Fatty acid profiling with GC-MS revealed linoleic acid and linolenic acid as the predominant essential fatty acids in AWO. Molecular docking analysis revealed potent molecular interactions of linoleic acid and linolenic acid with GLUT4. These results suggest the ability of AWO to improve testicular glucose metabolism and steroidogenesis and can be explored in the management of male infertility.

Paclitaxel-resistance facilitates glycolytic metabolism via Hexokinase-2-regulated ABC and SLC transporter genes in ovarian clear cell carcinoma

Ovarian clear cell carcinoma (OCCC) frequently develops resistance to platinum-based therapies, which is regarded as an aggressive subtype. However, metabolic changes in paclitaxel resistance remain unclear. Herein, we present the metabolic alternations of paclitaxel resistance in bioenergetic profiling in OCCC. Paclitaxel-resistant OCCC cells were developed and metabolically active with oxygen consumption rates (OCR) compared to parental cells. Metabolite profiling analysis revealed that paclitaxel-resistant OCCC cells reduced intracellular ATP and GTP influx rates, increasing the NADH/NAD+ ratio. We further demonstrated that paclitaxel-resistant OCCC cells led to characteristic alternations of metabolite levels in energy-requiring and energy-releasing steps of glycolysis and their corresponding glycolytic enzymes. Copy number alterations and RNA sequencing analysis demonstrated that ATP-binding cassette (ABC) transporters and solute carrier (SLC) transporter genes involved in glycolysis metabolism and molecular transport were enriched in paclitaxel-resistant OCCC cells. We first identified that Hexokinase 2 (HK2) expression is upregulated in paclitaxel-resistant OCCC cells to determine the quantity of glucose entering glycolysis. Utilizing proteolysis-targeting chimera (PROTAC) HK2 degraders, we also found that paclitaxel sensitivity, viability, and oxygen consumption rates under paclitaxel treatment were restored by HK2 degraders treatment, and decreased downstream expression of the ABC and SLC transporters was shown in OCCC cells. Taken together, these findings highlight the paclitaxel resistance in OCCC elucidates metabolic alternation, including ABC- and SLC- drug transporters, thereby affecting glycolysis metabolism in response to paclitaxel resistance, and HK2 may become a novel potential therapeutic target for paclitaxel resistance.

Hippocampal warburg effect mediates hydrogen sulfide-ameliorated diabetes-associated cognitive dysfunction: Involving promotion of hippocampal synaptic plasticity

Our previous studies have reported that hydrogen sulfide (H2S) has ability to improve diabetes-associated cognitive dysfunction (DACD), but the exact mechanisms remain unknown. Recent research reveals that Warburg effect is associated with synaptic plasticity which plays a key role in cognition promotion. Herein, the present study was aimed to demonstrate whether hippocampal Warburg effect contributes to H2S-ameliorated DACD and further explore its potential mechanism. We found that H2S promoted the hippocampal Warburg effect and inhibited the OxPhos in the hippocampus of STZ-induced diabetic rats. It also improved the hippocampal synaptic plasticity in STZ-induced diabetic rats, as evidenced by the change of microstructures and the expression of different key-enzymes. Furthermore, inhibited hippocampal Warburg effect induced by DCA markedly abolished the improvement of H2S on synaptic plasticity in the hippocampus of STZ-induced diabetic rats. DCA blocked H2S-attenuated the cognitive dysfunction in STZ-induced diabetic rats, according to the Y-maze, Novel Objective Recognition, and Morris Water Maze tests. Collectively, these findings indicated that the hippocampal Warburg effect mediates H2S-ameliorated DACD by improving hippocampal synaptic plasticity.

PI3K-dependent reprogramming of hexokinase isoforms controls glucose metabolism and functional responses of B lymphocytes

B lymphocyte activation triggers metabolic reprogramming essential for B cell differentiation and mounting a healthy immune response. Here, we investigate the regulation and function of glucose-phosphorylating enzyme hexokinase 2 (HK2) in B cells. We report that both activation-dependent expression and mitochondrial localization of HK2 are regulated by the phosphatidylinositol 3-kinase (PI3K) signaling pathway. B cell-specific deletion of HK2 in mice caused mild perturbations in B cell development. HK2-deficient B cells show impaired functional responses in vitro and adapt to become less dependent on glucose and more dependent on glutamine. HK2 deficiency impairs glycolysis, alters metabolite profiles, and alters flux of labeled glucose carbons into downstream pathways. Upon immunization, HK2-deficient mice exhibit impaired germinal center, plasmablast, and antibody responses. HK2 expression in primary human chronic lymphocytic leukemia (CLL) cells was associated with recent proliferation and could be reduced by PI3K inhibition. Our study implicates PI3K-dependent modulation of HK2 in B cell metabolic reprogramming.

Systems biology approach for enhancing limonene yield by re-engineering Escherichia coli

Engineered microorganisms have emerged as viable alternatives for limonene production. However, issues such as low enzyme abundance or activities, and regulatory feedback/forward inhibition may reduce yields. To understand the underlying metabolism, we adopted a systems biology approach for an engineered limonene-producing Escherichia coli strain K-12 MG1655. Firstly, we generated time-series metabolomics data and, secondly, developed a dynamic model based on enzyme dynamics to track the native metabolic networks and the engineered mevalonate pathway. After several iterations of model fitting with experimental profiles, which also included 13C-tracer studies, we performed in silico knockouts (KOs) of all enzymes to identify bottleneck(s) for optimal limonene yields. The simulations indicated that ALDH/ADH (aldehyde dehydrogenase/alcohol dehydrogenase) and LDH (lactate dehydrogenase) suppression, and HK (hexokinase) enhancement would increase limonene yields. Experimental confirmation was achieved, where ALDH-ADH and LDH KOs, and HK overexpression improved limonene yield by 8- to 11-fold. Our systems biology approach can guide microbial strain re-engineering for optimal target production.

Cardiomyocyte Adaptation to Exercise: K+ Channels, Contractility and Ischemic Injury

Cardiovascular disease is a leading cause of morbidity and mortality, and exercise-training (TRN) is known to reduce risk factors and protect the heart from ischemia and reperfusion injury. Though the cardioprotective effects of exercise are well-documented, underlying mechanisms are not well understood. This review highlights recent findings and focuses on cardiac factors with emphasis on K+ channel control of the action potential duration (APD), β-adrenergic and adenosine regulation of cardiomyocyte function, and mitochondrial Ca2+ regulation. TRN-induced prolongation and shortening of the APD at low and high activation rates, respectively, is discussed in the context of a reduced response of the sarcolemma delayed rectifier potassium channel (IK) and increased content and activation of the sarcolemma KATP channel. A proposed mechanism underlying the latter is presented, including the phosphatidylinositol-3kinase/protein kinase B pathway. TRN induced increases in cardiomyocyte contractility and the response to adrenergic agonists are discussed. The TRN-induced protection from reperfusion injury is highlighted by the increased content and activation of the sarcolemma KATP channel and the increased phosphorylated glycogen synthase kinase-3β, which aid in preventing mitochondrial Ca2+ overload and mitochondria-triggered apoptosis. Finally, a brief section is presented on the increased incidences of atrial fibrillation associated with age and in life-long exercisers.

Endoplasmic reticulum stress is attenuated by glycolysis in lymphatic malformations

BACKGROUND

This study aims to investigate the role of endoplasmic reticulum stress (ER stress) in human dermal lymphatic endothelial cells (HDLECs) and lymphatic malformations (LMs) and its relationship with aerobic glycolysis and inflammation.

METHODS

The proliferation and apoptosis of HDLECs were examined with lipopolysaccharide (LPS) treatment. ER stress-associated proteins and glycolysis-related markers were detected by western blot. Glycolysis indexes were detected by seahorse analysis and lactic acid production assay kits. Immunohistochemistry was used to reveal the ER stress state of lymphatic endothelial cells (LECs) in LMs.

RESULTS

LPS induced ER stress in HDLECs but did not trigger detectable apoptosis. Intriguingly, LPS-treated HDLECs also showed increased glycolysis flux. Knockdown of Hexokinase 2, a key enzyme for aerobic glycolysis, significantly inhibited the ability of HDLECs to resist ER stress-induced apoptosis. Moreover, compared to normal skin, glucose-regulated protein 78 (GRP78/BIP), and phosphorylation protein kinase R-like kinase (p-PERK), two key ER stress-associated markers, were upregulated in LECs of LMs, which was correlated with the inflected state. In addition, excessively activated ER stress inhibited the progression of LMs in rat models.

CONCLUSIONS

These data indicate that glycolysis could rescue activated ER stress in HDLECs, which is required for the accelerated development of LMs.

IMPACT

Inflammation enhances both ER stress and glycolysis in LECs while glycolysis is required to attenuate the pro-apoptotic effect of ER stress. Endoplasmic reticulum (ER) stress is activated in lymphatic endothelial cells (LECs) of LMs, especially in inflammatory condition. The expression of ER stress-related proteins is increased in LMs and correlated with Hexokinase 2 expression. Pharmacological activation of ER stress suppresses the formation of LM lesions in the rat model. ER stress may be a promising and effective therapeutic target for the treatment of LMs.

Hyperglycemia selectively increases cerebral non-oxidative glucose consumption without affecting blood flow

Multiple studies have shown that hyperglycemia increases the cerebral metabolic rate of glucose (CMRglc) in subcortical white matter. This observation remains unexplained. Using positron emission tomography (PET) and euinsulinaemic glucose clamps, we found, for the first time, that acute hyperglycemia increases non-oxidative CMRglc (i.e., aerobic glycolysis (AG)) in subcortical white mater as well as in medial temporal lobe structures, cerebellum and brainstem, all areas with low euglycemic CMRglc. Surprisingly, hyperglycemia did not change regional cerebral blood flow (CBF), the cerebral metabolic rate of oxygen (CMRO2), or the blood-oxygen-level-dependent (BOLD) response. Regional gene expression data reveal that brain regions where CMRglc increased have greater expression of hexokinase 2 (HK2). Simulations of glucose transport revealed that, unlike hexokinase 1, HK2 is not saturated at euglycemia, thus accommodating increased AG during hyperglycemia.

Tethering of hexokinase 2 to mitochondria promotes resistance of liver cancer cells to natural killer cell cytotoxicity

Hexokinases (HKs) control the first step of glucose catabolism. A switch of expression from liver HK (glucokinase, GCK) to the tumor isoenzyme HK2 is observed in hepatocellular carcinoma progression. Our prior work revealed that HK isoenzyme switch in hepatocytes not only regulates hepatic metabolic functions but also modulates innate immunity and sensitivity to Natural Killer (NK) cell cytotoxicity. This study investigates the impact of HK2 expression and its mitochondrial binding on the resistance of human liver cancer cells to NK-cell-induced cytolysis. We have shown that HK2 expression induces resistance to NK cell cytotoxicity in a process requiring mitochondrial binding of HK2. Neither HK2 nor GCK expression affects target cells' ability to activate NK cells. In contrast, mitochondrial binding of HK2 reduces effector caspase 3/7 activity both at baseline and upon NK-cell activation. Furthermore, HK2 tethering to mitochondria enhances their resistance to cytochrome c release triggered by tBID. These findings indicate that HK2 mitochondrial binding in liver cancer cells is an intrinsic resistance factor to cytolysis and an escape mechanism from immune surveillance.

Icariin alleviates oxygen-induced retinopathy by targeting microglia hexokinase 2

Retinopathy of prematurity (ROP) is a retinal disease-causing retinal neovascularization that can lead to blindness. Oxygen-induced retinopathy (OIR) is a widely used ROP animal model. Icariin (ICA) has anti-oxidative and anti-inflammation properties; however, whether ICA has a regulatory effect on OIR remains unclear. In this study, ICA alleviated pathological neovascularization, microglial activation and blood-retina barrier (BRB) damage in vivo. Further results indicated that endothelial cell tube formation, migration and proliferation were restored by ICA treatment in vitro. Proteomic microarrays and molecular mimicry revealed that ICA can directly bind to hexokinase 2 (HK2) and decrease HK2 protein expression in vivo and in vitro. In addition, ICA inhibited the AKT/mTOR/HIF1α pathway activation. The effects of ICA on pathological neovascularization, microglial activation and BRB damage disappeared after HK2 overexpression in vivo. Similarly, the endothelial cell function was revised after HK2 overexpression. HK2 overexpression reversed ICA-induced AKT/mTOR/HIF1α pathway inhibition in vivo and in vitro. Therefore, ICA prevented pathological angiogenesis in OIR in an HK2-dependent manner, implicating ICA as a potential therapeutic agent for ROP.

Brain Glucose Metabolism and COMT Val 158 Met Polymorphism in Female Patients with Work-Related Stress

Stress is a ubiquitous challenge in modern societies. Symptoms range from mood swings and cognitive impairment to autonomic symptoms. This study explores the link between work-related stress and the neurobiological element of brain processing, testing the hypothesis that patients with occupational stress have altered cerebral glucose consumption compared to healthy controls. The participants' present conditions were evaluated using an adapted WHO SCAN interview. Neural activity at rest was assessed by positron emission tomography (PET) with the glucose analogue [18F]fluorodeoxyglucose. Participants were genotyped for the Val158Met polymorphism of the COMT gene, believed to influence stress resilience. This study included 11 women with work-related stress and 11 demographically comparable healthy controls aged 28-62 years, with an average of 46.2 years. The PET scans indicated clusters of decreased glucose consumption primarily located in the white matter of frontal lobe sub-gyral areas in stress patients. COMT Val158Met polymorphism detection indicated no immediate relation of the homozygous alleles and stress resilience; however, healthy controls mainly had the heterozygous allele. In conclusion, the results support that work-related stress does affect the brain in the form of altered glucose metabolism, suggesting neurobiological effects could be related to white matter abnormalities rather than gray matter deterioration. Genotyping indicates a more complex picture than just that of the one type being more resilient to stress. Further studies recruiting a larger number of participants are needed to confirm our preliminary findings.

Two hexokinases of the shrimp Penaeus (Litopenaeus) vannamei are differentially expressed during oxygen limited conditions

The white shrimp Penaeus (Litopenaeus) vannamei is the most cultivated shrimp worldwide. Compared to other shrimp species, it has higher resistance to adverse conditions. During hypoxia, the shrimp reduces oxygen consumption and adjusts energy metabolism via anaerobic glycolysis, among other strategies. Hexokinase (HK) is the first enzyme of glycolysis and a key regulation point. In mammals and other vertebrates, there are several tissue-specific HK isoforms with differences in expression and enzyme activity. In contrast, crustacean HKs have been relatively little studied. We studied the P. vannamei HK isoforms during hypoxia and reoxygenation. We cloned two HK1 sequences named HK1-long (1455 bp) and HK1-short (1302 bp), and one HK2 (1344 bp). In normoxia, total HK1 expression is higher in hepatopancreas, while HK2 is higher in gills. Severe hypoxia (1 mg/L of DO) after 12 h exposure and 1 h of reoxygenation increased HK1 expression in both organs, but HK2 expression changed differentially. In hepatopancreas, HK2 expression increased in 6 and 12 h of hypoxia but diminished to normoxia levels after reoxygenation. In gills, HK2 expression decreased after 12 h of hypoxia. HK activity increased in hepatopancreas after 12 h hypoxia, opposite to gills. These results indicate that shrimp HK isoforms respond to hypoxia and reoxygenation in a tissue-specific manner. Intracellular glucose levels did not change in any case, showing the shrimp ability to maintain glucose homeostasis during hypoxia.

A-Syn(ful) MAM: A Fresh Perspective on a Converging Domain in Parkinson's Disease

Parkinson's disease (PD) is a disease of an unknown origin. Despite that, decades of research have provided considerable evidence that alpha-synuclein (αSyn) is central to the pathogenesis of disease. Mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) are functional domains formed at contact sites between the ER and mitochondria, with a well-established function of MAMs being the control of lipid homeostasis within the cell. Additionally, there are numerous proteins localized or enriched at MAMs that have regulatory roles in several different molecular signaling pathways required for cellular homeostasis, such as autophagy and neuroinflammation. Alterations in several of these signaling pathways that are functionally associated with MAMs are found in PD. Taken together with studies that find αSyn localized at MAMs, this has implicated MAM (dys)function as a converging domain relevant to PD. This review will highlight the many functions of MAMs and provide an overview of the literature that finds αSyn, in addition to several other PD-related proteins, localized there. This review will also detail the direct interaction of αSyn and αSyn-interacting partners with specific MAM-resident proteins. In addition, recent studies exploring new methods to investigate MAMs will be discussed, along with some of the controversies regarding αSyn, including its several conformations and subcellular localizations. The goal of this review is to highlight and provide insight on a domain that is incompletely understood and, from a PD perspective, highlight those complex interactions that may hold the key to understanding the pathomechanisms underlying PD, which may lead to the targeted development of new therapeutic strategies.

HK2 promotes migration and invasion of intrahepatic cholangiocarcinoma via enhancing cancer stem-like cells' resistance to anoikis

Cancer stem-like cells (CSLCs) and anoikis resistance play crucial roles in the metastasis of cancers. However, it remains unclear whether CSLCs are related to anoikis resistance in intrahepatic cholangiocarcinoma (ICC). Here we identified a group of stemness-related anoikis genes (SRAGs) via bioinformatic analysis of public data. Accordingly, a novel anoikis-related classification was established and it divided ICC into C1 and C2 type. Different type ICC displayed distinct prognosis, molecular as well immune characteristics. Furthermore, we found one key SRAGs via several machine learning algorithms. HK2 was up-regulated in tumor-repopulating cells (TRCs) of ICC, a kind of CSLCs with a potent resistance to anoikis. Its up-regulation may be caused by the activation of MTORC1 signaling in ICC-TRCs. And inhibition of HK2 significantly increased anoikis and decreased migration as well invasion in ICC-TRCs. Our studies provide an insight into the molecular mechanism underlying the resistance of ICC-TRCs to anoikis and enhance the evidences for targeting HK2 in ICC.

Immunometabolic reprogramming of macrophages with inhalable CRISPR/Cas9 nanotherapeutics for acute lung injury intervention

Acute lung injury (ALI) represents a critical respiratory condition typified by rapid-onset lung inflammation, contributing to elevated morbidity and mortality rates. Central to ALI pathogenesis lies macrophage dysfunction, characterized by an overabundance of pro-inflammatory cytokines and a shift in metabolic activity towards glycolysis. This study emphasizes the crucial function of glucose metabolism in immune cell function under inflammatory conditions and identifies hexokinase 2 (HK2) as a key regulator of macrophage metabolism and inflammation. Given the limitations of HK2 inhibitors, we propose the CRISPR/Cas9 system for precise HK2 downregulation. We developed an aerosolized core-shell liposomal nanoplatform (CSNs) complexed with CaP for efficient drug loading, targeting lung macrophages. Various CSNs were synthesized to encapsulate an mRNA based CRISPR/Cas9 system (mCas9/gHK2), and their gene editing efficiency and HK2 knockout were examined at both gene and protein levels in vitro and in vivo. The CSN-mCas9/gHK2 treatment demonstrated a significant reduction in glycolysis and inflammation in macrophages. In an LPS-induced ALI mouse model, inhaled CSN-mCas9/gHK2 mitigated the proinflammatory tumor microenvironment and reprogrammed glucose metabolism in the lung, suggesting a promising strategy for ALI prevention and treatment. This study highlights the potential of combining CRISPR/Cas9 gene editing with inhalation delivery systems for effective, localized pulmonary disease treatment, underscoring the importance of targeted gene modulation and metabolic reprogramming in managing ALI. STATEMENT OF SIGNIFICANCE: This study investigates an inhalable CRISPR/Cas9 gene editing system targeting pulmonary macrophages, with the aim of modulating glucose metabolism to alleviate Acute Lung Injury (ALI). The research highlights the role of immune cell metabolism in inflammation, as evidenced by changes in macrophage glucose metabolism and a notable reduction in pulmonary edema and inflammation. Additionally, observed alterations in macrophage polarization and cytokine levels in bronchoalveolar lavage fluid suggest potential therapeutic implications. These findings not only offer insights into possible ALI treatments but also contribute to the understanding of immune cell metabolism in inflammatory diseases, which could be relevant for various inflammatory and metabolic disorders.

Glycolysis and tumor progression promoted by the m6A writer VIRMA via m6A-dependent upregulation of STRA6 in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and lethal malignancies, highlighting the urgent need to elucidate the underlying oncogenic mechanisms. VIRMA is a classic isoform of methyltransferases that participates in epigenetic transcriptomic modification in eukaryotic mRNAs. However, the exact roles of VIRMA in PDAC remain unclear. Here, we identified that VIRMA is highly expressed in PDAC, and histone modifications of the promoter may partly account for this dysregulation. Moreover, VIRMA is closely related to glycolysis and poor prognosis in PDAC. We further determined that STRA6 is a direct downstream target of VIRMA in PDAC by RNA sequencing (RNA-seq) and m6A sequencing (m6A-seq). VIRMA is involved in gene expression regulation via 3' UTR targeting of STRA6 mRNA. Furthermore, the m6A reader IGF2BP2 was shown to critically contribute to the stability of STRA6 mRNA. We describe the role of VIRMA in promoting signaling via the STRA6/STAT3 axis, which results in increased levels of HIF-1α, a key activator of glycolysis. In vivo and in vitro experiments reveal that the VIRMA-STRA6-STAT3-HIF-1α axis plays an instrumental role in glycolysis and tumor progression in PDAC. In conclusion, we demonstrate that VIRMA can increase glycolysis in PDAC by upregulating STRA6, a cell surface membrane protein that stimulates the STAT3 pathway, thereby activating HIF-1α and leading to pancreatic cancer malignancy. Overall, our data strongly suggest that the VIRMA-STRA6-STAT3-HIF-1α axis is a viable therapeutic target in PDAC.

Transcription factor Tox2 is required for metabolic adaptation and tissue residency of ILC3 in the gut

Group 3 innate lymphoid cells (ILC3) are the major subset of gut-resident ILC with essential roles in infections and tissue repair, but how they adapt to the gut environment to maintain tissue residency is unclear. We report that Tox2 is critical for gut ILC3 maintenance and function. Gut ILC3 highly expressed Tox2, and depletion of Tox2 markedly decreased ILC3 in gut but not at central sites, resulting in defective control of Citrobacter rodentium infection. Single-cell transcriptional profiling revealed decreased expression of Hexokinase-2 in Tox2-deficient gut ILC3. Consistent with the requirement for hexokinases in glycolysis, Tox2-/- ILC3 displayed decreased ability to utilize glycolysis for protein translation. Ectopic expression of Hexokinase-2 rescued Tox2-/- gut ILC3 defects. Hypoxia and interleukin (IL)-17A each induced Tox2 expression in ILC3, suggesting a mechanism by which ILC3 adjusts to fluctuating environments by programming glycolytic metabolism. Our results reveal the requirement for Tox2 to support the metabolic adaptation of ILC3 within the gastrointestinal tract.

The determinants of metabolic discrepancies in aerobic glycolysis: Providing potential targets for breast cancer treatment

Altered aerobic glycolysis is the robust mechanism to support cancer cell survival and proliferation beyond the maintenance of cellular energy metabolism. Several investigators portrayed the important role of deregulated glycolysis in different cancers, including breast cancer. Breast cancer is the most ubiquitous form of cancer and the primary cause of cancer death in women worldwide. Breast cancer with increased glycolytic flux is hampered to eradicate with current therapies and can result in tumor recurrence. In spite of the low order efficiency of ATP production, cancer cells are highly addicted to glycolysis. The glycolytic dependency of cancer cells provides potential therapeutic strategies to preferentially kill cancer cells by inhibiting glycolysis using antiglycolytic agents. The present review emphasizes the most recent research on the implication of glycolytic enzymes, including glucose transporters (GLUTs), hexokinase (HK), phosphofructokinase (PFK), pyruvate kinase (PK), lactate dehydrogenase-A (LDHA), associated signalling pathways and transcription factors, as well as the antiglycolytic agents that target key glycolytic enzymes in breast cancer. The potential activity of glycolytic inhibitors impinges cancer prevalence and cellular resistance to conventional drugs even under worse physiological conditions such as hypoxia. As a single agent or in combination with other chemotherapeutic drugs, it provides the feasibility of new therapeutic modalities against a wide spectrum of human cancers.

Arecoline promotes Akt-c-Myc-driven aerobic glycolysis in esophageal epithelial cells

Aerobic glycolysis is a typical metabolic rearrangement for tumorigenesis. Arecoline is of explicit carcinogenicity, numerous works demonstrate its mutagenicity, genotoxicity, and cytotoxicity. However, the effects of arecoline on aerobic glycolysis of esophageal epithelial cells remain unclear. In the present study, 5 μM arecoline efficiently increased HK2 expression to induce aerobic glycolysis in Het-1A-Are and NE2-Are cells. The mechanistic analysis showed that arecoline activated the Akt-c-Myc signaling pathway and reduced the GSK3β-mediated phosphorylation of c-Myc on Thr58 to prevent its ubiquitination and destruction, subsequently promoting HK2 transcription and expression. Taken together, these results suggest that arecoline can induce aerobic glycolysis of esophageal epithelial cells and further confirm that arecoline is a carcinogen harmful to human health.

Related mechanisms, current treatments, and new perspectives in meningioma

Meningiomas are non-glial tumors that are the most common primary brain tumors in adults. Although meningioma can possibly be cured with surgical excision, variations in atypical/anaplastic meningioma have a high recurrence rate and a poor prognosis. As a result, it is critical to develop novel therapeutic options for high-grade meningiomas. This review highlights the current histology of meningiomas, prevalent genetic and molecular changes, and the most extensively researched signaling pathways and therapies in meningiomas. It also reviews current clinical studies and novel meningioma treatments, including immunotherapy, microRNAs, cancer stem cell methods, and targeted interventions within the glycolysis pathway. Through the examination of the complex landscape of meningioma biology and the highlighting of promising therapeutic pathways, this review opens the way for future research efforts aimed at improving patient outcomes in this prevalent intracranial tumor entity.

Targeted degradation of hexokinase 2 for anti‑inflammatory treatment in acute lung injury

Acute lung injury (ALI) is an acute inflammatory lung disease associated with both innate and adaptive immune responses. Hexokinase 2 (HK2) is specifically highly expressed in numerous types of inflammation‑related diseases and models. In the present study in vitro and in vivo effects of targeted degradation of HK2 on ALI were explored. The degradation of HK2 by the targeting peptide TAT (transactivator of transcription protein of HIV‑1)‑ataxin 1 (ATXN1)‑chaperone‑mediated autophagy‑targeting motif (CTM) was demonstrated by ELISA and western blotting in vitro and in vivo. The inhibitory effects of TAT‑ATXN1‑CTM on lipopolysaccharide (LPS)‑induced inflammatory responses were examined using ELISAs. The therapeutic effects of TAT‑ATXN1‑CTM on LPS‑induced ALI were examined via histological examination and ELISAs in mice. 10 µM TAT‑ATXN1‑CTM administration decreased HK2 protein expression and the secretion of proinflammatory cytokines (TNF‑α and IL‑1β) without altering HK2 mRNA expression in LPS‑treated both in vitro and in vivo, while pathological lung tissue damage and the accumulation of leukocytes, neutrophils, macrophages and lymphocytes in ALI were also significantly suppressed by 10 µM TAT‑ATXN1‑CTM treatment. TAT‑ATXN1‑CTM exhibited anti‑inflammatory activity in vitro and decreased the severity of ALI in vivo. HK2 degradation may represent a novel therapeutic approach for ALI.

Mitochondrial Kinase Signaling for Cardioprotection

Myocardial ischemia/reperfusion injury is reduced by cardioprotective adaptations such as local or remote ischemic conditioning. The cardioprotective stimuli activate signaling cascades, which converge on mitochondria and maintain the function of the organelles, which is critical for cell survival. The signaling cascades include not only extracellular molecules that activate sarcolemmal receptor-dependent or -independent protein kinases that signal at the plasma membrane or in the cytosol, but also involve kinases, which are located to or within mitochondria, phosphorylate mitochondrial target proteins, and thereby modify, e.g., respiration, the generation of reactive oxygen species, calcium handling, mitochondrial dynamics, mitophagy, or apoptosis. In the present review, we give a personal and opinionated overview of selected protein kinases, localized to/within myocardial mitochondria, and summarize the available data on their role in myocardial ischemia/reperfusion injury and protection from it. We highlight the regulation of mitochondrial function by these mitochondrial protein kinases.

AAV-mediated upregulation of VDAC1 rescues the mitochondrial respiration and sirtuins expression in a SOD1 mouse model of inherited ALS

Mitochondrial dysfunction represents one of the most common molecular hallmarks of both sporadic and familial forms of amyotrophic lateral sclerosis (ALS), a neurodegenerative disorder caused by the selective degeneration and death of motor neurons. The accumulation of misfolded proteins on and within mitochondria, as observed for SOD1 G93A mutant, correlates with a drastic reduction of mitochondrial respiration and the inhibition of metabolites exchanges, including ADP/ATP and NAD+/NADH, across the Voltage-Dependent Anion-selective Channel 1 (VDAC1), the most abundant channel protein of the outer mitochondrial membrane. Here, we show that the AAV-mediated upregulation of VDAC1 in the spinal cord of transgenic mice expressing SOD1 G93A completely rescues the mitochondrial respiratory profile. This correlates with the increased activity and levels of key regulators of mitochondrial functions and maintenance, namely the respiratory chain Complex I and the sirtuins (Sirt), especially Sirt3. Furthermore, the selective increase of these mitochondrial proteins is associated with an increase in Tom20 levels, the receptor subunit of the TOM complex. Overall, our results indicate that the overexpression of VDAC1 has beneficial effects on ALS-affected tissue by stabilizing the Complex I-Sirt3 axis.

A gain of function mutation in AKT1 increases hexokinase 2 and diminishes oxidative stress in meningioma

Increasing evidence suggests the oncogenic role of missense mutation (AKT1-E17K) of AKT1 gene in meningiomas. Upon investigating the connection between the pro-tumorigenic role of AKT1-E17K and cellular metabolic adaptations, elevated levels of glycolytic enzyme hexokinase 2 (HK2) was observed in meningioma patients with AKT1-E17K compared to patients harboring wild-type AKT1. In vitro experiments also suggested higher HK2 levels and its activity in AKT1-E17K cells. Treatment with the conventional drug of choice AZD5363 (a pan AKT inhibitor) enhanced cell death and diminished HK2 levels in AKT1 mutants. Given the role of AKT phosphorylation in eliciting inflammatory responses, we observed increased levels of inflammatory mediators (IL-1β, IL6, IL8, and TLR4) in AKT1-E17K cells compared to AKT1-WT cells. Treatment with AKT or HK2 inhibitors dampened the heightened levels of inflammatory markers in AKT1-E17K cells. As AKT and HK2 regulates redox homeostasis, diminished ROS generation concomitant with increased levels of NF-E2- related factor 2 (Nrf2) and superoxide dismutase 1 (SOD1) were observed in AKT1-E17K cells. Increased sensitivity of AKT1-E17K cells to AZD5363 in the presence of HK2 inhibitor Lonidamine was reversed upon treatment with ROS inhibitor NAC. By affecting metabolism, inflammation, and redox homeostasis AKT1-E17K confers a survival advantage in meningioma cells. Our findings suggest that targeting AKT-HK2 cross-talk to induce ROS-dependent cell death could be exploited as novel therapeutic approach in meningiomas.

Immmunometabolism of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a potentially fatal chronic autoimmune disease which is underlain by complex dysfunction of the innate and adaptive immune systems. Although a series of well-defined genetic and environmental factors have been implicated in disease etiology, neither the development nor the persistence of SLE is well understood. Given that several disease susceptibility genes and environmental factors interact and influence inflammatory lineage specification through metabolism, the field of immunometabolism has become a forefront of cutting edge research. Along these lines, metabolic checkpoints of pathogenesis have been identified as targets of effective therapeutic interventions in mouse models and validated in clinical trials. Ongoing studies focus on mitochondrial oxidative stress, activation of the mechanistic target of rapamycin, calcium signaling, glucose utilization, tryptophan degradation, and metabolic cross-talk between gut microbiota and the host immune system.