Enzymatic Synthesis Research Articles

An overlooked nanofluids effect from Fe3O4 nanoparticles enhances mass transfer in anammox granular sludge

Magnetite (Fe3O4) particles have been widely reported to enhance the anammox's activity in anammox granular sludge (AnGS), yet the underlying mechanisms remain unclear. This study demonstrates that both Fe3O4 microparticles (MPs) and nanoparticles (NPs) at a dosage of 200 mg Fe3O4/L significantly increased the specific anammox activity (SAA) of AnGS. Additionally, the transcriptional activities of the hzs and hdh genes involved in the anammox process, as well as the heme c content in AnGS, were also notably enhanced. Notably, Fe3O4 NPs were more effective than MPs in boosting anammox activity within AnGS. Mechanistically, Fe3O4 MPs released free iron, which anammox bacteria utilized to promote the synthesis of key enzymes, thereby enhancing their activity. Compared to MPs, Fe3O4 NPs not only elevated the synthesis of these key enzymes to a higher level but also induced a nanofluids effect on the surface of AnGS, improving substrate permeability and accessibility to intragranular anammox bacteria. Moreover, the nanofluids effect was identified as the primary mechanism through which Fe3O4 NPs enhanced anammox activity within AnGS. These findings provide new insights into the effects of nanoparticles on granular sludge systems, extending beyond AnGS.

Copper@MXene quantum dots-aerogel: High-performance peroxidase mimic for direct pirimiphos-methyl pesticide detection

Due to their cost-efficiency and heightened sensitivity, the rational design of artificial nanozymes has become a paramount research direction. In this investigation, we elaborate on a simplified freeze-drying methodology for fabricating Cu@MXene quantum dots-aerogel (Cu@MQDs-aerogel), which possesses augmented peroxidase-mimicking activity. Through steady-state fluorometric analysis, we delve into the catalytic mechanism of Cu@MQDs-aerogel, uncovering its proficiency in decomposing H2O2 into reactive hydroxyl radicals (OH). Density functional theory (DFT) calculations further validate that the outstanding catalytic prowess of Cu@MQDs-aerogel stems from the interfacial Cu-Ti dimer active sites, significantly activating adsorbed H2O2 and facilitating its decomposition into OH. As a result, we introduce a sensitive colorimetric sensor for pirimiphos-methyl detection, achieving a low detection limit of 0.65 nM. Additionally, it exhibits a narrow relative standard deviation (RSD) interval spanning from 1.03 % to 2.66 %. This study introduces a novel strategy for the design and synthesis of MQDs-based peroxidase-like enzymes, highlighting their significant potential in environmental pollutant detection.

GhLCYε-3 characterized as a lycopene cyclase gene responding to drought stress in cotton

Drought stress significantly affects crop productivity. Carotenoids are essential photosynthetic pigment for plants, bacteria, and algae, with signaling and antioxidant functions. Lutein is a crucial branch product in the carotenoid synthesis pathway, which effectively improves the stress tolerance of higher plants. lycopene cyclase, a central enzyme for lutein synthesis, holds great significance in regulating lutein production. This research establishes a correlation between lutein content and stress resistance by measuring the drought resistance and lutein content of various cotton materials. To identify which crucial genes are associated with lutein, the lycopene cyclase family (LCYs) was analyzed. The research found that LCYs form a highly conserved family divided into two subfamilies, LCY-ε (lycopene ε-cyclase) and LCY-β (lycopene β-cyclase). Most members of the LCY family contain photoresponsive elements and abscisic acid elements. qRT-PCR demonstrates showed that most genes responded positively to drought stress, and GhLCYε-3 was expressed significantly differently under drought stress. Virus-induced gene silencing (VIGS) assay showed that the content of GhLCYε-3 was significantly increased with MDA and PRO, and the contents of chlorophyll and lutein were significantly decreased in pYL156 plants. The decrease in GhLCYε-3 expression is speculated to lead to reduced lutein content in vivo, resulting in the accumulation of reactive oxygen species (ROS) and decreased drought tolerance. This research enriched the understanding of LCY gene family and lutein function, and provided a new reference for cotton planting in arid areas. SynopsisLycopene cyclase plays an important role in enhancing the ability of scavenging ROS and drought resistance of plants.

Innovative strategy of ZIF-90 for co-immobilization of whole cells and enzymes in biocatalytic D-phenyllactic acid synthesis.

In this study, we endeavored to catalyze the biosynthesis of D-phenyllactic (D-PLA) from L-Phenylalanine (L-Phe) through a one-pot method. However, the crucial enzymes for the biosynthesis of phenylpyruvate (PPA), amino acid oxidase (L-AAD), is a membrane-bound protein. Herein, we proposed a novel co-immobilization strategy of whole cells and enzymes, integrating them into ZIF-90 to achieve efficient biosynthesis of D-PLA. Consequently, we embarked on integrating both enzyme and E. coli into ZIF-90, ultimately obtaining the novel biocatalyst E. coli/LDH@ZIF-90. This achievement facilitated the cascade reaction between LDH and E. coli, enabling a streamlined one-pot bioconversion process. The morphology and structure of E. coli/LDH@ZIF-90 were thoroughly characterized using a range of methods, including XRD, SEM, FT-IR, CLSM, and XPS, which confirmed that the material had been successfully synthesized. Further activity experiments revealed that E. coli/LDH@ZIF-90 exhibited good stability even under harsh conditions. Additionally, the biocatalyst retained 76% of its initial catalytic activity after completing six cycles. Moreover, when utilized for the biosynthesis of D-PLA, this system demonstrated an impressive conversion rate of 85.2% after 12h. The successful cascade catalysis from L-Phe to D-PLA underscored the potential of the enzyme-cell cascade catalytic system, offering valuable insights for its potential industrial applications.

Clerodendranthus spicatus [Orthosiphon aristatus (Blume) Miq.] maintains uric acid homeostasis via regulating gut microbiota and restrains renal inflammation in hyperuricemic nephropathy

IntroductionThe kidney damage caused by the deposition of uric acid in the kidneys is of urgent need for new treatment drugs due to its complex pathogenesis. Orthosiphon aristatus (Blume) Miq. Also known as C. spicatus, which has a significant therapeutic effect on hyperuricemia nephropathy (HN), however, the specific mechanism of its action is still unknown.MethodsThe HN mice model was constructed using adenine (AD) and potassium oxonate (PO), and serum biochemical indexes, kidney pathological changes, xanthine oxidase (XOD) activity in the liver, and renal protein expressions of phosphoribose pyrophosphate synthetase (PRPS) and uric acid transporter were detected. The effects of C. spicatus on uric acid lowering, anti-inflammation, and renal protection of HN mice were verified. The effect of C. spicatus on gut microbiota was assessed by 16 S rRNA sequencing. Establish pseudo-sterile mice through the combined treatment of ampicillin, neomycin, and vancomycin to verify the role of gut microbiota in improving HN in C. spicatus.ResultsIn HN mice, C. spicatus could significantly reduce serum uric acid levels and improve renal function. In addition, C. spicatus modulated gut microbiota and decreased the relative abundance of Bacteroides, Prevotellaceae_UCG-001 and Alistipes, and increased the abundance of Alloprevotella and Lachnospiraceae_NK4A136_group.C.spicatus altered the expression of the renal urate transporter and key enzymes in hepatic urate synthesis, leading to a decrease in serum uric acid levels. C. spicatus alleviated kidney inflammation by inhibiting the activation of the NLRP3 and TLR4/MYD88 inflammatory pathways, and reduced the level of kidney inflammatory factors. It also improved kidney damage by inhibiting the process of renal epithelial-mesenchymal transition, and improved kidney fibrosis. In pseudo-sterile HN mice, without the effect of gut microbiota, the uric acid lowering, anti-inflammatory, and renal fibrosis improving effects of C. spicatus were significantly reduced.ConclusionOur results demonstrated that C. spicatus could reduce uric acid levels, anti-inflammatory effects, and improve HN by regulating the gut microbiota. This provides a novel scientific basis for the clinical application of C. spicatus.

An Yb(OTf)₃-Mediated Indirect Activation Strategy for the Stereoselective Synthesis of α-Sialosides from 2-Fluorosialyl Donors.

Most of chemical sialylation reactions are conducted at extremely low temperatures to achieve the formation of challenging sialic acid linkages with high stereoselectivities. Performing chemical sialylation at room temperature independent of enzymatic methods represents an effective approach, particularly significant in biological and biochemical research. Our study aims to develop a convenient method of providing α-sialyl glycosides. Herein, we carry out sialyation using Yb(OTf)3 as an activating promoter at room temperature in tetrahydrofurane and obtain excellent stereoselectivities when reacting the N-acetyl-5-N,4-O-carbonyl-2-fluorosialyl donor with galacto- or glucopyranosides. The advantages of this method include an over eight-month shelf life of the sialyl donors and minimal formation of the hydrolyzed or eliminated side-products. Sialylation of the C3 hydroxyl group in galactosides affords exclusive α-selectivities, and a one-pot synthesis of trisaccharide is accomplished by application of this method. Finally, we anticipate that this sialylation strategy can compensate for the limitations of the current enzymatic synthesis of complex glycans.

Dimethyl Fumarate Reduces Methylglyoxal-derived Carbonyl Stress Through Nrf2/GSH Activation in SH-SY5Y Cells.

Carbonyl stress refers to the excessive accumulation of advanced glycation end products (AGEs) in mammalian tissues. This phenomenon plays a significant role in the pathogenesis of various diseases, including diabetes, chronic renal failure, arteriosclerosis, and central nervous system (CNS) disorders. We have previously demonstrated that an increase in glutathione concentration, dependent on the nuclear factor erythroid 2-related factor 2 (Nrf2) system, provides a potent cytoprotective effect against Methylglyoxal (MGO)-induced carbonyl stress. Meanwhile, dimethyl fumarate (DMF), known for its Nrf2-activating effects, was recently approved as a treatment for multiple sclerosis (MS), a neurodegenerative disease. DMF is a first line therapy for relapsing-remitting MS and may also be effective for other neurodegenerative conditions. However, the detailed mechanisms by which DMF mitigates neurodegenerative pathologies remain unclear. This study investigates the impact of DMF on anticarbonyl activity and its underlying mechanism focusing on the accumulation of carbonyl protein in the cell. MGO, a glucose metabolite, was used to induce carbonylation in the neuronal cell line. MGO is a typical carbonyl compound that readily reacts with arginine and lysine residues to form AGE-modified proteins. Methylglyoxal-derived hydroimidazolone 1 (MG-H1) often forms uncharged, hydrophobic residues on the protein surface, which can affect protein distribution and lead to misfolding. Our findings indicate that DMF increases levels of glutathione (GSH), glutamate cysteine ligase modifier subunit (GCLM), and nuclear Nrf2 in SH-SY5Y cells. Importantly, DMF pretreatment significantly reduced the accumulation of MG-H1-modified proteins. Furthermore, this effect of DMF was diminished when Nrf2 expression was suppressed and when GCL, a rate-limiting enzyme in GSH synthesis, was inhibited. Thus, the increase in GSH levels, leading to the activation of the Nrf2 pathway, a key factor in DMF's ability to suppress the accumulation of MG-H1-modified proteins. This study is the first to demonstrate that DMF possesses strong anticarbonyl stress activity in neuronal cells. Therefore, future research may extend the application of DMF to other CNS diseases associated with carbonyl stress, such as Alzheimer's and Parkinson's disease.

Branched-chain amino acids promote hepatic Cyp7a1 expression and bile acid synthesis via suppressing FGF21-ERK pathway.

Branched-chain amino acids (BCAAs) including leucine, isoleucine and valine have been linked with metabolic and cardiovascular diseases. BCAAs homeostasis is tightly controlled by their catabolic pathway. BCKA dehydrogenase (BCKD) complex is the rate-limiting step for BCAA catabolism. Mitochondrial phosphatase 2C (PP2Cm) dephosphorylates the BCKD E1alpha subunit and activates BCKD complex. Deficiency of PP2Cm impairs BCAA catabolism, leading to higher plasma BCAA concentrations. Emerging evidence shows that bile acids are key regulators of glucose, lipid and energy metabolism. In this study, we investigated whether a direct link existed between BCAAs and bile acids metabolism. Wild-type mice were fed with normal-BCAA or high-BCAA diet, while PP2Cm deficiency mice were fed with normal chow for 14 weeks. The mice were fasted for 6 h before tissue harvest to exclude metabolic changes due to immediate food intake. We showed that the bile acids in tissues and feces were significantly elevated in wild-type mice fed with high-BCAA diet as well as in PP2Cm deficiency mice fed with normal chow. These mice displayed significantly increased expression of cholesterol 7 alpha-hydroxylase (CYP7A1), the rate-limiting enzyme of bile acid synthesis in liver, and 7α-hydroxy-4-cholesten-3-one (C4), a freely diffusible metabolite downstream of CYP7A1 in plasma. BCAAs induced Cyp7a1 expression in cultured hepatocytes. In mouse liver and cultured hepatocytes, we demonstrated that elevated BCAAs inhibited fibroblast growth factor 21 (FGF21) expression and ERK signaling pathway. Direct inhibition of ERK by U0126 (800 nM) markedly induced Cyp7a1 expression in cultured hepatocytes. Moreover, the induced Cyp7a1 expression and inhibitory effects of BCAAs on ERK signaling pathway were abolished by treatment with recombinant FGF21 protein in mouse liver and cultured hepatocytes. Collectively, this study demonstrates a direct link between BCAAs and bile acid synthesis. BCAAs promotes Cyp7a1 expression and bile acid synthesis in liver via inhibiting FGF21-ERK signaling pathway. BCAAs-regulated bile acid synthesis and homeostasis may contribute to developing novel therapeutic strategies for the treatment of metabolic disorders.

Tumor cell-derived spermidine promotes a pro-tumorigenic immune microenvironment in glioblastoma via CD8+ T cell inhibition.

The glioblastoma (GBM) microenvironment is enriched in immunosuppressive factors that potently interfere with the function of cytotoxic T lymphocytes. Cancer cells can directly impact the immune system, but the mechanisms driving these interactions are not completely clear. Here we demonstrate that the polyamine metabolite spermidine (SPD) is elevated in the GBM tumor microenvironment. Exogenous administration of SPD drives tumor aggressiveness in an immune-dependent manner in pre-clinical mouse models via reduction of CD8+ T cell frequency and reduced cytotoxic function. Knockdown of ornithine decarboxylase, the rate-limiting enzyme in spermidine synthesis, did not impact cancer cell growth in vitro but did result in extended survival. Furthermore, glioblastoma patients with a more favorable outcome had a significant reduction in spermidine compared to patients with a poor prognosis. Our results demonstrate that spermidine functions as a cancer cell-derived metabolite that drives tumor progression by reducing CD8+ T cell number and function.

Magnesium and Zinc as Vital Micronutrients Enhancing Athletic Performance and Recovery – a Review

Introduction and Aim of the ReviewMagnesium and zinc are vital for cellular metabolism and maintaining homeostasis, playing a particularly significant role for athletes. Magnesium, which is largely stored in bones and muscles, is essential for protein synthesis. Zinc, a critical trace element found in muscle and bone tissue, participates in over 300 enzymatic reactions, acts as an antioxidant and making both minerals crucial for physical performance. This study aims to explore the physiological role of magnesium (Mg) and zinc (Zn) in the context of athletic performance and to examine their impact on energy metabolism, muscle function, protein synthesis and potential benefits of Mg and Zn supplementation for improving athletic outcomes and post-exercise recovery. MethodsA comprehensive review of scientific literature was conducted through a thorough search of the PubMed database to explore the latest findings on the utility of magnesium and zinc in sports. Only articles in English were considered. Current KnowledgeThe review results indicate that Mg and Zn play critical roles in energy metabolism, muscle and immune system health. Mg deficiency can impair muscle function and reduce endurance, while its supplementation supports muscle relaxation, cardiovascular health, and respiratory efficiency. Although required in small amounts, Zn is indispensable for enzymatic activity, protein synthesis, hormonal balance, and muscle recovery, making it vital for post-exercise recovery and immune response modulation. ConclusionsAvailable data suggest that Mg and Zn supplementation may positively influence athletic performance, energy metabolism, and recovery post-exercise, though further research is needed to establish specific supplementation guidelines. This review provides a foundation for developing supplementation strategies aimed at enhancing athletic performance and supporting healthy recovery.

P63 affects distinct metabolic pathways during keratinocyte senescence, evaluated by metabolomic profile and gene expression analysis

Unraveling the molecular nature of skin aging and keratinocyte senescence represents a challenging research project in epithelial biology. In this regard, depletion of p63, a p53 family transcription factor prominently expressed in human and mouse epidermis, accelerates both aging and the onset of senescence markers in vivo animal models as well as in ex vivo keratinocytes. Nonetheless, the biochemical link between p63 action and senescence phenotype remains largely unexplored. In the present study, through ultrahigh performance liquid chromatography–tandem mass spectroscopy (UPLC–MS/MS) and gas chromatography/mass spectrometry (GC/MS) metabolomic analysis, we uncover interesting pathways linking replicative senescence to metabolic alterations during p63 silencing in human keratinocytes. Integration of our metabolomic profiling data with targeted transcriptomic investigation empowered us to demonstrate that absence of p63 and senescence share similar modulation profiles of oxidative stress markers, pentose phosphate pathway metabolites and lyso-glycerophospholipids, the latter due to enhanced phospholipases gene expression profile often under p63 direct/indirect gene control. Additional biochemical features identified in deranged keratinocytes include a relevant increase in lipids production, glucose and pyruvate levels as confirmed by upregulation of gene expression of key lipid synthesis and glycolytic enzymes, which, together with improved vitamins uptake, characterize senescence phenotype. Silencing of p63 in keratinocytes instead, translates into a blunted flux of metabolites through both glycolysis and the Krebs cycle, likely due to a p63-dependent reduction of hexokinase 2 and citrate synthase gene expression. Our findings highlight the potential role of p63 in counteracting keratinocyte senescence also through fine regulation of metabolite levels and relevant biochemical pathways. We believe that our research might contribute significantly to the discovery of new implications of p63 in keratinocyte senescence and related diseases.

Research on heavy metal enrichment and transportation in tea plant-soil systems of different varieties.

This study aimed to investigate heavy metal enrichment in different tea plant varieties and their distribution within different plant parts and to clarify the behavioral characteristics of heavy metals in the tea tree-soil system and their influencing factors. In this study, soil samples were collected from the root zones of 13 tea tree varieties in Guizhou, which had been planted for 10years. The aim was to compare the physicochemical properties of tea plantation soils under soil-forming matrixes and consistent management. Additionally, the study investigated the enrichment and transportation patterns of Cd, Cr, Cu, Pb, Zn, and Ni in the tea tree-soil systems of different tea tree varieties. The results showed that the planting of tea trees decreased the soil pH by 0.5; soil nutrients decreased; soil Pb, Cr, Ni, Cu, and Zn contents in the root zone increased; and Cd content decreased. Heavy metals were mainly enriched in the roots, and Zn, Cu, Ni, and other elements related to the protein and enzyme synthesis of tea trees could be mostly transported to the stems and leaves. There were significant differences in the enrichment and transportation of heavy metals among the different tea tree varieties. Under consistent soil-forming parent material, soil pH, organic matter, nutrients, and other indices only had a significant effect on heavy metal enrichment in the tea tree roots. Therefore, in areas with high background soil heavy metal contents, the construction of tea plantations should be based on regional soil environmental conditions to choose tea tree varieties with low heavy metal enrichment capacities to avoid the risk of high background soil heavy metals on the safe production of tea for consumers.

PCYT2 inhibits epithelial-to-mesenchymal transition in colorectal cancer by elevating YAP1 phosphorylation.

Metabolic reprogramming is a common feature in tumor progression and metastasis. Like proteins, lipids can transduce signals through lipid-protein interactions. During tumor initiation and metastasis, dysregulation of the Hippo pathway plays a critical role. Specifically, the inhibition of YAP1 phosphorylation leads to the relocation of YAP1 to the nucleus to activate transcription of genes involved in metastasis. Although recent studies reveal the involvement of phosphatidylethanolamine (PE) synthesis enzyme phosphoethanolamine cytidylyltransferase 2 (PCYT2) in tumor chemoresistance, the impact of PCYT2 on tumor metastasis remains elusive. Here, we showed that PCYT2 was significantly downregulated in metastatic colorectal cancer (CRC) and acted as a tumor metastasis suppressor. Mechanistically, PCYT2 increased the interaction between PEBP1 and YAP1-phosphatase PPP2R1A, thus disrupting PPP2R1A-YAP1 association. As a result, phosphorylated-YAP1 levels were increased, leading to YAP1 degradation through the ubiquitin protease pathway. YAP1 reduction in the nucleus repressed the transcription of ZEB1 and Snail2, eventually resulting in metastasis suppression. Our work provides insight into the role of PE synthesis in regulating metastasis and presents PCYT2 as a potential therapeutic target for CRC.

Nuclear IMPDH2 controls the DNA damage response by modulating PARP1 activity

Nuclear metabolism and DNA damage response are intertwined processes, but the precise molecular links remain elusive. Here, we explore this crosstalk using triple-negative breast cancer (TNBC) as a model, a subtype often prone to DNA damage accumulation. We show that the de novo purine synthesis enzyme IMPDH2 is enriched on chromatin in TNBC compared to other subtypes. IMPDH2 chromatin localization is DNA damage dependent, and IMPDH2 repression leads to DNA damage accumulation. On chromatin, IMPDH2 interacts with and modulates PARP1 activity by controlling the nuclear availability of NAD+ to fine-tune the DNA damage response. However, when IMPDH2 is restricted to the nucleus, it depletes nuclear NAD+, leading to PARP1 cleavage and cell death. Our study identifies a non-canonical nuclear role for IMPDH2, acting as a convergence point of nuclear metabolism and DNA damage response.

TMIC-49. TUMOR-DERIVED SPERMIDINE DRIVES IMMUNE SUPPRESSION IN THE GLIOBLASTOMA MICROENVIRONMENT VIA CD8 T CELL DEPLETION AND FUNCTIONAL ATTENUATION

Abstract A hallmark of glioblastoma (GBM) is an immunosuppressive microenvironment that is partially driven by tumor cell-derived secreted factors, highlighting the need for a more complete understanding of local immune suppressive mechanism. Altered secreted metabolite levels are observed in the GBM microenvironment; specifically, spermidine (a polyamine), which functions to drive cell proliferation, apoptosis, T cell lineage commitment, and myeloid cell-mediated suppression. However, the direct link between GBM cell-derived spermidine and the tumor microenvironment has yet to be determined. In syngeneic mouse GBM models, spermidine levels were increased in the tumor microenvironment and exogenous administration of spermidine accelerated tumor aggressiveness in an immune dependent-manner. Mechanistically, spermidine administration increased apoptosis of CD8+ T-cells and generated an exhausted phenotype. When ornithine decarboxylase (ODC1, the rate limiting enzyme in spermidine synthesis), was knocked down in tumor cells, no direct effect was observed on tumor cell growth. However, there was an increase in time to tumor succumbence and a concomitant increase in CD8+ T-cells and decrease in CD8+ T cell exhaustion. In GBM patients, there was a negative correlation between ODC1 expression and CD8+ T-cells present near the tumor. Additionally, patients with a favorable prognosis had significantly lower intratumoral levels of spermidine compared to patients with a poor prognosis. Taken together, these results demonstrate that spermidine functions as a tumor cell-derived metabolite that drives tumor progression through reducing CD8+T cell number and altering their phenotype. These findings have clinical implications as clinical trials using a polyamine biosynthesis inhibitor alone have not been very effective in GBM patients, suggesting the need for additional combination immunotherapies. Finally, spermidine is also produced at prominent levels by commensal gut microbes as well as absorbed from consumption of foods such as mushrooms; investigation into how these distal spermidine sources impact GBM growth via the gut-brain axis is actively ongoing.

Human PERIOD3 variants lead to winter depression-like behaviours via glucocorticoid signalling.

Our brain adapts to seasonal changes. Mis-adaptations may lead to seasonal patterns in several psychiatric disorders, but we know little regarding the underlying mechanisms. Our previous work identified two variants in the human circadian clock gene PERIOD3 (PER3), that is, P415A and H417R, which are associated with winter depression, but whether and how these variants lead to the disorder remain to be characterized. Here we find that male mice carrying human P415A and H417R display winter depression-like behaviours that are caused by the actions of P415A and H417R in the adrenal gland. Systemic corticosterone level is downregulated in adaptation to shortening of day length, while P415A and H417R eliminate this downregulation by increasing corticosterone synthesis. Enhanced glucocorticoid signalling represses the transcription of Tph2, which encodes the rate-limiting enzyme of serotonin synthesis, leading to increased depression-like behaviours. Taken together, our findings unveil a mechanism according to which human variants contribute to seasonal mood traits.

CTNI-37. INTERIM SAFETY ANALYSIS OF THE PHASE IB/II RANDOMIZED ANTI-GLUTAMATERGIC DRUG REPURPOSING TRIAL GLUGLIO IN PATIENTS WITH NEWLY DIAGNOSED GLIOBLASTOMA (NCT05664464)

Abstract The advent of cancer neuroscience has significantly advanced our understanding of brain tumor biology, yet the clinical implications remain largely unexplored. Glutamate, the most abundant excitatory neurotransmitter, presents a potential therapeutic target in brain tumors. Glioblastoma cells synthesize and secrete large amounts of glutamate, driving epilepsy, neuronal death, tumor growth, and invasion. Several brain-penetrating drugs, approved for other conditions, can inhibit glutamate synthesis, secretion, and signaling. These drugs include: (i) gabapentin, an anti-seizure medication that inhibits the glutamate synthesis enzyme branched-chain amino acid transaminase 1; (ii) sulfasalazine, an anti-inflammatory drug that blocks the cystine-glutamate exchanger system Xc, reducing glutamate secretion; and (iii) memantine, a cognitive enhancer that prevents glutamate-driven, calcium-induced neuronal death and tumor cell invasion by blocking N-methyl-D-aspartate type glutamate receptors. The multi-center, open-label, parallel-group, two-arm, 1:1 randomized phase Ib/II trial GLUGLIO is investigating the efficacy of a daily oral anti-glutamatergic triple combination of gabapentin, sulfasalazine, and memantine until tumor progression, in conjunction with standard chemoradiotherapy, compared to chemoradiotherapy alone. The primary endpoint is progression-free survival at 6 months (PFS-6). A sample size of 120 patients was determined to detect an increase in PFS-6 from 50% to 70%, with 80% power, using exploratory hypothesis testing at a one-sided significance level of 10%. Secondary endpoints include overall survival, seizure-free survival, response rate, quality of life for patients and caregivers, symptom burden, cognitive functioning, tumor glutamate levels (measured by magnetic resonance spectroscopy), and the use of anti-convulsants and steroids. Each drug is dosed up to the maximum approved amount. Results from the phase Ib part of the trial, including an interim safety analysis, will be presented at the conference.

LncRNA NORFA promotes the synthesis of estradiol and inhibits the apoptosis of sow ovarian granulosa cells through SF-1/CYP11A1 axis

BackgroundBiosynthesis of 17β-estradiol (E2) is a crucial ovarian function in mammals, which is essential for follicular development and pregnancy outcome. Exploring the epigenetic regulation of E2 synthesis is beneficial for maintaining ovary health and the optimal reproductive traits. NORFA is the first validated sow fertility-associated long non-coding RNA (lncRNA). However, its role on steroidogenesis is elusive. The aim of this study is to investigate the regulation and underlying mechanism of NORFA to E2 synthesis in sow granulosa cells (GCs).ResultsThrough Pearson correlation analysis and comparative detection, we found that NORFA expression was positively correlated with the levels of pregnenolone (PREG) and E2 in follicles, which also exhibited similar alteration patterns during follicular atresia. ELISA was conducted and indicated for the first time that NORFA induced the synthesis of PREG and E2 in sow GCs in a dose- and time-dependent manner. RNA-seq, GSEA and quantitative analyses results validated that CYP11A1, the coding gene of P450SCC which is the first step rate-limiting enzyme of E2 synthesis, was a positive functional target of NORFA. Mechanistically, NORFA promotes SF-1 expression by stabilizing NR5A1 mRNA through directly interacting with its 3’-UTR, and also tethers SF-1 to shuttle into nucleus. Additionally, SF-1 in the nucleus activates CYP11A1 transcription by directly binding to its promoter, which ultimately induces E2 synthesis and inhibits GC apoptosis.ConclusionOur findings highlight that NORFA, a multifunctional lncRNA, induces E2 synthesis and inhibits GC apoptosis through the SF-1/CYP11A1 axis in a ceRNA-independent manner, which provide valuable clues and potential targets for follicular atresia inhibition and female fertility improvement.

Evolutionary dynamics and functional characterization of proximal duplicated sorbitol-6-phosphate dehydrogenase genes in Rosaceae.

Sorbitol is a critical photosynthate and storage substance in the Rosaceae family. Sorbitol 6-phosphate dehydrogenase (S6PDH) functions as the pivotal rate-limiting enzyme in sorbitol synthesis. The origin and functional diversification of S6PDH in Rosaceae remain unclear, largely due to the complicated interplay of gene duplications. Here, we investigated the synteny relationships among all identified S6PDH genes in representative genomes within the Rosaceae family. By integrating phylogenetic analyses, we elucidated the lineage-specific expansion and syntenic conservation of S6PDH across diverse Rosaceae plant lineages. We found that S6PDH can be traced back to a pair of proximal duplicated genes of the common ancestor of the Rosaceae, and the further amplification of S6PDH in the Maleae primarily relies on WGD events in their lineages. In Rosaceae species, multiple copies of the S6PDH gene are preliminarily divided into two main clades (Clade 1 and Clade 2) based on sequence similarity. These clades have evolved to acquire different functional directions. In Clade 1, lineage-specific transposition events in the Amygdaloideae have led to changes in gene expression patterns and promoted lineage evolution. This is mainly characterized by a decrease in enzymatic activity and transcriptional expression in the leaves, but also includes specific functional diversification, such as sustained post-harvest fruit expression and enhanced expression under biotic stress in certain tissues. In contrast, S6PDH in the Rosoideae and Dryadoideae has not undergone additional duplications beyond early proximal duplication. The loss of exons and variations in exon length might the key factor leading to reduced enzymatic activity in the Clade 2 proximal gene pairs. Collectively, our findings illuminate the dynamic nature of S6PDH evolution and reveal the intricate interplay between duplication, transposition, and functional diversification. This work not only contributes valuable insights into the genetic mechanisms underlying sorbitol metabolism but also establish a crucial foundation for future investigations aimed at comprehensively characterizing the variations of sorbitol metabolism across different subfamilies within the Rosaceae family.

Pivotal roles for cancer cell-intrinsic mPGES-1 and autocrine EP4 signaling in suppressing antitumor immunity.

Tumor cell-derived prostaglandin E2 (PGE2) is a tumor cell-intrinsic factor that supports immunosuppression in the tumor microenvironment (TME) by acting on the immune cells, but the impact of PGE2 signaling in tumor cells on the immunosuppressive TME is unclear. We demonstrate that deleting the PGE2 synthesis enzyme or disrupting autocrine PGE2 signaling through EP4 receptors on tumor cells reverses the T cell-low, myeloid cell-rich TME, activates T cells, and suppresses tumor growth. Knockout (KO) of Ptges (the gene encoding the PGE2 synthesis enzyme mPGES-1) or the EP4 receptor gene (Ptger4) in KPCY (KrasG12D P53R172H Yfp CrePdx) pancreatic tumor cells abolished growth of implanted tumors in a T cell-dependent manner. Blockade of the EP4 receptor in combination with immunotherapy, but not immunotherapy alone, induced complete tumor regressions and immunological memory. Mechanistically, Ptges- and Ptger4-KO tumor cells exhibited altered T and myeloid cell attractant chemokines, became more susceptible to TNF-α-induced killing, and exhibited reduced adenosine synthesis. In hosts treated with an adenosine deaminase inhibitor, Ptger4-KO tumor cells accumulated adenosine and gave rise to tumors. These studies reveal an unexpected finding - a nonredundant role for the autocrine mPGES-1/PGE2/EP4 signaling axis in pancreatic cancer cells, further nominating mPGES-1 inhibition and EP4 blockade as immune-sensitizing therapy in cancer.