Regulation Of Cell Metabolism Research Articles

Berberine: Potential preventive and therapeutic strategies for human colorectal cancer.

Colorectal cancer (CRC) is a common digestive tract tumor, with incidences continuing to rise. Although modern medicine has extended the survival time of CRC patients, its adverse effects and the financial burden cannot be ignored. CRC is a multi-step process and can be caused by the disturbance of gut microbiome and chronic inflammation's stimulation. Additionally, the presence of precancerous lesions is also a risk factor for CRC. Consequently, scientists are increasingly interested in identifying multi-target, safe, and economical herbal medicine and natural products. This paper summarizes berberine's (BBR) regulatory mechanisms in the occurrence and development of CRC. The findings indicate that BBR regulates gut microbiome homeostasis and controls mucosal inflammation to prevent CRC. In the CRC stage, BBR inhibits cell proliferation, invasion, and metastasis, blocks the cell cycle, induces cell apoptosis, regulates cell metabolism, inhibits angiogenesis, and enhances chemosensitivity. BBR plays a role in the overall management of CRC. Therefore, using BBR as an adjunct to CRC prevention and treatment could become a future trend in oncology.

Citric Acid: A Nexus Between Cellular Mechanisms and Biomaterial Innovations.

Citrate-based biodegradable polymers have emerged as a distinctive biomaterial platform with tremendous potential for diverse medical applications. By harnessing their versatile chemistry, these polymers exhibit a wide range of material and bioactive properties, enabling them to regulate cell metabolism and stem cell differentiation through energy metabolism, metabonegenesis, angiogenesis and immunomodulation. Moreover, the recent U.S. Food and Drug Administration (FDA) clearance of the biodegradable poly(octamethylene citrate) (POC)/hydroxyapatite-based orthopedic fixation devices represent a translational research milestone for biomaterial science. POC joins a short list of biodegradable synthetic polymers that have ever been authorized by the FDA for use in humans. The clinical success of POC has sparked enthusiasm and accelerated the development of next-generation citrate-based biomaterials. This review presents a comprehensive, forward-thinking discussion on the pivotal role of citrate chemistry and metabolism in various tissue regeneration and on the development of functional citrate-based metabotissugenic biomaterials for regenerative engineering applications. This article is protected by copyright. All rights reserved.

Antiviral Shrimp lncRNA06 Possesses Anti-Tumor Activity by Inducing Apoptosis of Human Gastric Cancer Stem Cells in a Cross-Species Manner

Virus infection causes the metabolic disorder of host cells, whereas the metabolic disorder of cells is one of the major causes of tumorigenesis, suggesting that antiviral molecules might possess anti-tumor activities by regulating cell metabolism. As the key regulators of gene expression, long non-coding RNAs (lncRNAs) play vital roles in the regulation of cell metabolism. However, the influence of antiviral lncRNAs on tumorigenesis has not been explored. To address this issue, the antiviral and anti-tumor capacities of shrimp lncRNAs were characterized in this study. The results revealed that shrimp lncRNA06, having antiviral activity in shrimp, could suppress the tumorigenesis of human gastric cancer stem cells (GCSCs) via triggering apoptosis of GCSCs in a cross-species manner. Shrimp lncRNA06 could sponge human miR-17-5p to suppress the stemness of GCSCs via the miR-17-5p-p21 axis. At the same time, shrimp lncRNA06 could bind to ATP synthase subunit beta (ATP5F1B) to enhance the stability of the ATP5F1B protein in GCSCs, thus suppressing the tumorigenesis of GCSCs. The in vivo data demonstrated that shrimp lncRNA06 promoted apoptosis and inhibited the stemness of GCSCs through interactions with ATP5F1B and miR-17-5p, leading to the suppression of the tumorigenesis of GCSCs. Therefore, our findings highlighted that antiviral lncRNAs possessed anti-tumor capacities and that antiviral lncRNAs could be the anti-tumor reservoir for the treatment of human cancers.

RPGRIP1L as a new biomarker for prognosis and tumor immune of breast cancer.

The Retinitis pigmentosa GTPase regulator interacting protein 1-like (RPGRIP1L) gene encodes an important protein that performs various physiological functions. Variants of RPGRIP1L are related to a number of diseases. However, it is currently unknown whether RPGRIP1L is correlated with breast invasive carcinoma (BRCA). In BRCA tissue specimens, the expression of RPGRIP1L was found to be elevated in comparison to its levels in normal breast tissue. A notable decline in survival rates was associated with patients exhibiting heightened RPGRIP1L gene expression. Consistent with these findings, our data also show the above results. Furthermore, elevated expression of RPGRIP1L corresponded with a spectrum of unfavorable clinicopathological features, including the presence of human epidermal growth factor receptor 2 (HER2) positive, estrogen receptor (ER) positive, over 60 years old, T2, N0, and N3. At the same time, our research indicated that 50 genes and 15 proteins were positively related to RPGRIP1L, and that these proteins and genes were mostly involved in T cell proliferation, immune response, cytokine activity, and metabolic regulation. In addition, in the present study, there was a significant correlation between RPGRIP1L expression and immune cell infiltration. Finally, we found that four Chemicals could downregulate the expression of RPGRIP1L. Altogether, our results strongly indicated that RPGRIP1L might serve as a new prognostic biomarker for BRCA.

Prevalence of Liver Steatosis in Tuberous Sclerosis Complex Patients: A Retrospective Cross-Sectional Study.

Introduction: Tuberous sclerosis complex (TSC) is a genetic disease caused by pathogenetic variants in either the TSC1 or TSC2 genes. Consequently, the mechanistic target of the rapamycin complex 1 (mTORC1) pathway, a regulator of cell growth, metabolism, and survival, becomes inappropriately activated, leading to the development of benign tumors in multiple organs. The role of mTORC1 in lipid metabolism and liver steatosis in TSC patients has not been well-studied, and clinical data on liver involvement in this population are scarce. Methods: We conducted a retrospective, cross-sectional study to compare liver steatosis in TSC patients with age-, sex-, BMI-, and diabetes status-matched controls. Participants with a definite diagnosis of TSC were recruited from the TSC clinic at UZ Brussel. Liver steatosis was quantified using the fat signal fraction from in-phase and out-of-phase MRI, with a threshold of ≥5% defining the presence of steatosis. We also evaluated the prevalence of liver angiomyolipomata in the TSC group and analyzed risk factors for both liver steatosis and angiomyolipomata. Results: The study included 59 TSC patients and 59 matched controls. The mean fat signal fraction was 4.0% in the TSC group and 3.9% in the controls, showing no significant difference (two-tailed Wilcoxon signed ranks test, p = 0.950). Liver steatosis was observed in 15.3% of TSC patients compared to 23.7% of the controls, which was not statistically significant (two-tailed McNemar test, p = 0.267). Liver angiomyolipomata were identified in 13.6% of the TSC cohort. Conclusions: Our study, describing in detail the liver phenotype of TSC patients, did not reveal a significant difference in the prevalence of MRI-assessed liver steatosis in a large cohort of TSC patients compared to a closely matched control group.

The ion channel TRPM8 is a direct target of the immunosuppressant rapamycin in primary sensory neurons.

The mechanistic target of rapamycin (mTOR) signalling pathway is a key regulator of cell growth and metabolism. Its deregulation is implicated in several diseases. The macrolide rapamycin, a specific inhibitor of mTOR, has immunosuppressive, anti-inflammatory and antiproliferative properties. Recently, we identified tacrolimus, another macrolide immunosuppressant, as a novel activator of TRPM8 ion channels, involved in cold temperature sensing, thermoregulation, tearing and cold pain. We hypothesized that rapamycin may also have agonist activity on TRPM8 channels. Using calcium imaging and electrophysiology in transfected HEK293 cells and wildtype or Trpm8 KO mouse DRG neurons, we characterized rapamycin's effects on TRPM8 channels. We also examined the effects of rapamycin on tearing in mice. Micromolar concentrations of rapamycin activated rat and mouse TRPM8 channels directly and potentiated cold-evoked responses, effects also observed in human TRPM8 channels. In cultured mouse DRG neurons, rapamycin increased intracellular calcium levels almost exclusively in cold-sensitive neurons. Responses were markedly decreased in Trpm8 KO mice or by TRPM8 channel antagonists. Cutaneous cold thermoreceptor endings were also activated by rapamycin. Topical application of rapamycin to the eye surface evokes tearing in mice by a TRPM8-dependent mechanism. These results identify TRPM8 cationic channels in sensory neurons as novel molecular targets of the immunosuppressant rapamycin. These findings may help explain some of its therapeutic effects after topical application to the skin and the eye surface. Moreover, rapamycin could be used as an experimental tool in the clinic to explore cold thermoreceptors.

IRE1α pathway: A potential bone metabolism mediator.

Osteoblasts and osteoclasts collaborate in bone metabolism, facilitating bone development, maintaining normal bone density and strength, and aiding in the repair of pathological damage. Endoplasmic reticulum stress (ERS) can disrupt the intracellular equilibrium between osteoclast and osteoblast, resulting in dysfunctional bone metabolism. The inositol-requiring enzyme-1α (IRE1α) pathway-the most conservative unfolded protein response pathway activated by ERS-is crucial in regulating cell metabolism. This involvement encompasses functions such as inflammation, autophagy, and apoptosis. Many studies have highlighted the potential roles of the IRE1α pathway in osteoblasts, chondrocytes, and osteoclasts and its implication in certain bone-related diseases. These findings suggest that it may serve as a mediator for bone metabolism. However, relevant reviews on the role of the IRE1α pathway in bone metabolism remain unavailable. Therefore, this review aims to explore recent research that elucidated the intricate roles of the IRE1α pathway in bone metabolism, specifically in osteogenesis, chondrogenesis, osteoclastogenesis, and osteo-immunology. The findings may provide novel insights into regulating bone metabolism and treating bone-related diseases.

Nuclear mTOR Signaling Orchestrates Transcriptional Programs Underlying Cellular Growth and Metabolism.

mTOR is a central regulator of cell growth and metabolism in response to mitogenic and nutrient signals. Notably, mTOR is not only found in the cytoplasm but also in the nucleus. This review highlights direct involvement of nuclear mTOR in regulating transcription factors, orchestrating epigenetic modifications, and facilitating chromatin remodeling. These effects intricately modulate gene expression programs associated with growth and metabolic processes. Furthermore, the review underscores the importance of nuclear mTOR in mediating the interplay between metabolism and epigenetic modifications. By integrating its functions in nutrient signaling and gene expression related to growth and metabolism, nuclear mTOR emerges as a central hub governing cellular homeostasis, malignant transformation, and cancer progression. Better understanding of nuclear mTOR signaling has the potential to lead to novel therapies against cancer and other growth-related diseases.

Abstract PO3-05-09: The impact of body mass index on CDK4/6 inhibitor treatment survival outcomes in metastatic breast cancer

Abstract Introduction: Cyclin-dependent kinase 4/6 inhibitors (CDK4/6is) are important in the treatment of hormone receptor-positive (HR+)/HER2-negative metastatic breast cancer (MBC). Previous studies have shown that CDK4/6is affect metabolic processes and cell metabolism, including adipogenesis, lipid synthesis, and glucose regulation. Obesity has been associated with worse survival in breast cancer. We aimed to assess the effect of body mass index (BMI) on survival outcomes in patients treated with CDK4/6is for MBC. Methods: Patients diagnosed with metastatic HR+/HER2-negative BC and who were treated with palbociclib, ribociclib, or abemaciclib from 6/10/2015 to 12/28/2022 were selected from the Montefiore Health system database and followed until 3/24/2023. The patients were divided into three groups according to BMI level as follows; normal: 18.5-24.9 kg/m2, overweight: 25-29.9 kg/m2 and obese: ≥ 30 kg/m2. Patients were also stratified by BMI measured after 3 months of therapy. Characteristics of the patients and tumors in the subgroups were compared using chi-squared/Fisher’s exact test for categorical data and Kruskal-Wallis/Wilcox signed rank tests for continuous data. Kaplan-Meier and Cox proportional hazards analysis were used to compare overall survival (OS) and progression free survival (PFS). Results: Among 221 patients, 66 were normal weight, 78 were overweight, and 77 were obese. There was no statistically significant difference in clinicopathological characteristics among the cohorts. Neither BMI measured at baseline nor after 3 months of therapy had any association with OS (P = 0.8 at baseline and P = 0.1 after 3 months) or PFS (P = 0.4 at baseline and P = 0.6 after 3 months). Multivariable analysis showed no statistically significant association between BMI and worse OS (HR: 1.1 for overweight, P = 0.7; and 0.96 for obese, P = 0.9) or worse PFS (HR: 0.9 for overweight, P = 0.8; and 0.76 for obese, P = 0.5). Multivariate analysis revealed a significant effect of obese BMI after 3 months of treatment on OS (HR: 0.48, P = 0.035) but not on PFS (HR: 0.88, P = 0.8). Overweight BMI after 3 months of treatment was not found to have a significant effect on OS (HR: 0.49, P = 0.063) or PFS (HR: 0.89, P = 0.9). Conclusion: The clinical effectiveness of CDK4/6is was not found to be influenced by BMI measured prior to therapy; however, there may be an association between improved OS and obese BMI after 3 months of treatment. Median OS and PFS in patients with MBC comparing different BMI groups (normal, overweight, and obese) at baseline prior to therapy and after 3 months of therapy. Table 1 Baseline characteristics of patients with MBC comparing different BMI groups (normal, overweight, and obese) at baseline prior to therapy and after 3 months of therapy. Table 2 Table 3 Multivariable analysis of OS and PFS for patients with MBC comparing different BMI groups (normal, overweight, and obese) at baseline prior to therapy and after 3 months of therapy. Citation Format: Frank Zhang, Jesus Anampa Mesias. The impact of body mass index on CDK4/6 inhibitor treatment survival outcomes in metastatic breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-05-09.

Acyl-CoA synthetase 4 modulates mitochondrial function in breast cancer cells

Mitochondria are dynamic organelles that respond to cellular stress through changes in global mass, interconnection, and subcellular location. As mitochondria play an important role in tumor development and progression, alterations in energy metabolism allow tumor cells to survive and spread even in challenging conditions. Alterations in mitochondrial bioenergetics have been recently proposed as a hallmark of cancer, and positive regulation of lipid metabolism constitutes one of the most common metabolic changes observed in tumor cells. Acyl-CoA synthetase 4 (ACSL4) is an enzyme catalyzing the activation of long chain polyunsaturated fatty acids with a strong substrate preference for arachidonic acid (AA). High ACSL4 expression has been related to aggressive cancer phenotypes, including breast cancer, and its overexpression has been shown to positively regulate the mammalian Target of Rapamycin (mTOR) pathway, involved in the regulation of mitochondrial metabolism genes. However, little is known about the role of ACSL4 in the regulation of mitochondrial function and metabolism in cancer cells. In this context, our objective was to study whether mitochondrial function and metabolism, processes usually altered in tumors, are modulated by ACSL4 in breast cancer cells. Using ACSL4 overexpression in MCF-7 cells, we demonstrate that this enzyme can increase the mRNA and protein levels of essential mitochondrial regulatory proteins such as nuclear respiratory factor 1 (NRF-1), voltage-dependent anion channel 1 (VDAC1) and respiratory chain Complex III. Furthermore, respiratory parameters analysis revealed an increase in oxygen consumption rate (OCR) and in spare respiratory capacity (SRC), among others. ACSL4 knockdown in MDA-MB-231 cells led to the decrease in OCR and in SCR, supporting the role of ACSL4 in the regulation of mitochondrial bioenergetics. Moreover, ACSL4 overexpression induced an increase in glycolytic function, in keeping with an increase in mitochondrial respiratory activity. Finally, there was a decrease in mitochondrial mass detected in cells that overexpressed ACSL4, while the knockdown of ACSL4 expression in MDA-MB-231 cells showed the opposite effect. Altogether, these results unveil the role of ACSL4 in mitochondrial function and metabolism and expand the knowledge of ACSL4 participation in pathological processes such as breast cancer.

In Silico Intensive Analysis for the E4 Gene Evolution of Human Adenovirus Species D.

Adenovirus (Ad) is a ubiquitous pathogen capable of infecting a wide range of animals and humans. Human Adenovirus (HAdV) can cause severe infection, particularly in individuals with compromised immune systems. To date, over 110 types of HAdV have been classified into seven species from A to G, with the majority belonging to the human adenovirus species D (HAdV-D). In the HAdV-D, the most significant factor for the creation of new adenovirus types is homologous recombination between viral genes involved in determining the virus tropism or evading immune system of host cells. The E4 gene, consisting of seven Open Reading Frames (ORFs), plays a role in both the regulation of host cell metabolism and the replication of viral genes. Despite long-term studies, the function of each ORF remains unclear. Based on our updated information, ORF2, ORF3, and ORF4 have been identified as regions with relatively high mutations compared to other ORFs in the E4 gene, through the use of in silico comparative analysis. Additionally, we managed to visualize high mutation sections, previously undetectable at the DNA level, through a powerful amino acid sequence analysis tool known as proteotyping. Our research has revealed the involvement of the E4 gene in the evolution of human adenovirus, and has established accurate sequence information of the E4 gene, laying the groundwork for further research.

Mechanisms of vibration-induced structural myocardial remodeling

The review analyzes literature data on structural changes in the heart of patients with vibration disease, as detected by echocardiographic methods. Particularly, it highlights concentric remodeling of the left ventricle chambers and disturbances in diastolic function. The review also discusses a 1.2-fold decrease in heart structure intensity compared to healthy individuals (p 0.05). Furthermore, it examines changes in morphometric and bioenergetic parameters of cardiomyocytes under different experimental vibration modes (7 and 56 sessions at a frequency of 8 Hz), confirming the disruptions in the relationship between the spatial configuration of the heart cavities, contractile ability, and energy supply potential. Loss of cardiac myofibrils represents the transition from myocardial hypertrophy to decompensation, accompanied by an increase in degenerative (dystrophic) signs such as the loss of sarcomeres in cardiomyocytes. Understanding these pathological (morphological) processes requires consideration of various mediators that regulate cell metabolism, proliferation, growth, and survival, including stromal interaction molecule, calcium ATPase of the endo(sarco)plasmic reticulum, inositol-1,4,5-triphosphate receptor, protein that forms CRAC channels, and transient receptor potential canonical. The degradation system of the extracellular matrix, including matrix metalloproteinases and tissue inhibitors, plays a crucial role in structural cardiac remodeling. This system regulates the rate of mRNA synthesis on the DNA matrix by binding to specific DNA regions that control cardiac nutrition and plasticity. The review suggests that these findings can help explain some patterns of cardiac remodeling development in patients with vibration disease and determine the direction of pathogenetically based therapy. This therapy should consider not only the vibration-protective effect of drugs but also their ability to inhibit and regress myocardial remodeling.

Laryngeal Cancer Cells Metabolize 25-Hydroxyvitamin D3 and Respond to 24R,25-dihydroxyvitamin D3 via a Mechanism Dependent on Estrogen Receptor Levels.

Studies have evaluated vitamin D3's therapeutic potential in estrogen-responsive cancers, with conflicting findings. We have shown that the proliferation of breast cancer cells is regulated by 24R,25-dihydroxyvitamin D3 (24R,25(OH)2D3) depending on estrogen receptor alpha 66 (ERα66) expression, suggesting that this could also be the case for estrogen-sensitive laryngeal cancer cells. Accordingly, we examined levels of ERα isoforms in ERα66-positive UM-SCC-12 and ERα66-negative UM-SCC-11A cells and their response to 24R,25(OH)2D3. 24R,25(OH)2D3 stimulated proliferation, increased the expression of metastatic markers, and inhibited apoptosis in UM-SCC-12 cells while having the opposite effect in UM-SCC-11A cells. To evaluate if vitamin metabolites could act via autocrine/paracrine mechanisms, we assessed the expression, protein levels, and activity of vitamin D3 hydroxylases CYP24A1 and CYP27B1. Both cell types expressed both mRNAs; but the levels of the enzymes and their activities were differentially regulated by estrogen. ERα66-negative UM-SCC-11A cells produced more 24,25(OH)2D3 than UM-SCC-12 cells, but comparable levels of 1,25(OH)2D3 when treated with 25(OH)D3 These results suggest that the regulation of vitamin D3 metabolism in laryngeal cancer cells is modulated by ERα66 expression, and support a role for 24R,25(OH)2D3 as an autocrine/paracrine regulator of laryngeal cancer. The local metabolism of 25(OH)D3 should be considered when determining the potential of vitamin D3 in laryngeal cancer.

P4HA2 activates mTOR via hydroxylation and targeting P4HA2-mTOR inhibits lung adenocarcinoma cell growth.

Mammalian target of rapamycin (mTOR) kinase functions as a central regulator of cell growth and metabolism, and its complexes mTORC1 and mTORC2 phosphorylate distinct substrates. Dysregulation of mTOR signaling is commonly implicated in human diseases, including cancer. Despite three decades of active research in mTOR, much remains to be determined. Here, we demonstrate that prolyl 4-hydroxylase alpha-2 (P4HA2) binds directly to mTOR and hydroxylates one highly conserved proline 2341 (P2341) within a kinase domain of mTOR, thereby activating mTOR kinase and downstream effector proteins (e.g. S6K and AKT). Moreover, the hydroxylation of P2341 strengthens mTOR stability and allows mTOR to accurately recognize its substrates such as S6K and AKT. The growth of lung adenocarcinoma cells overexpressing mTORP2341A is significantly reduced when compared with that of cells overexpressing mTORWT. Interestingly, in vivo cell growth assays show that targeting P4HA2-mTOR significantly suppresses lung adenocarcinoma cell growth. In summary, our study reveals an undiscovered hydroxylation-regulatory mechanism by which P4HA2 directly activates mTOR kinase, providing insights for therapeutically targeting mTOR kinase-driven cancers.

A flexible self-supported electrochemical sensor Co-NC/PS@CC for real-time detection of cell-released H2O2

BackgroundHydrogen peroxide (H2O2) is an important reactive oxygen species (ROS) molecule involved in cell metabolism regulation, transcriptional regulation, and cytoskeleton remodeling. Real-time monitoring of H2O2 levels in live cells is of great significance for disease prevention and diagnosis. ResultsWe utilized carbon cloth (CC) as the substrate material and employed a single-atom catalysis strategy to prepare a flexible self-supported sensing platform for the real-time detection of H2O2 secreted by live cells. By adjusting the coordination structure of single-atom sites through P and S doping, a cobalt single-atom nanoenzyme Co-NC/PS with excellent peroxidase-like activity was obtained. Furthermore, we explored the enzyme kinetics and possible catalytic mechanism of Co-NC/PS. Due to the excellent flexibility, high conductivity, strong adsorption performance of carbon cloth, and the introduction of non-metallic atom-doped active sites, the developed Co-NC/PS@CC exhibited ideal sensing performance. Experimental results showed that the linear response range for H2O2 was 1–17328 μM, with a detection limit (LOD) of 0.1687 μM. Additionally, the sensor demonstrated good reproducibility, repeatability, anti-interference, and stability. SignificanceThe Co-NC/PS@CC prepared in this study has been successfully applied for detecting H2O2 secreted by MCF-7 live cells, expanding the application of single-atom nanoenzymes in live cell biosensing, with significant implications for health monitoring and clinical diagnostics.

Tissue-resident memory T cells: decoding intra-organ diversity with a gut perspective.

Tissue-resident memory T cells (TRM) serve as the frontline of host defense, playing a critical role in protection against invading pathogens. This emphasizes their role in providing rapid on-site immune responses across various organs. The physiological significance of TRM is not just confined to infection control; accumulating evidence has revealed that TRM also determine the pathology of diseases such as autoimmune disorders, inflammatory bowel disease, and cancer. Intensive studies on the origin, mechanisms of formation and maintenance, and physiological significance of TRM have elucidated the transcriptional and functional diversity of these cells, which are often affected by local cues associated with their presence. These were further confirmed by the recent remarkable advancements of next-generation sequencing and single-cell technologies, which allow the transcriptional and phenotypic characterization of each TRM subset induced in different microenvironments. This review first overviews the current knowledge of the cell fate, molecular features, transcriptional and metabolic regulation, and biological importance of TRM in health and disease. Finally, this article presents a variety of recent studies on disease-associated TRM, particularly focusing and elaborating on the TRM in the gut, which constitute the largest and most intricate immune network in the body, and their pathological relevance to gut inflammation in humans.

The role and therapeutic potential of SIRTs in sepsis.

Sepsis is a life-threatening organ dysfunction caused by the host's dysfunctional response to infection. Abnormal activation of the immune system and disturbance of energy metabolism play a key role in the development of sepsis. In recent years, the Sirtuins (SIRTs) family has been found to play an important role in the pathogenesis of sepsis. SIRTs, as a class of histone deacetylases (HDACs), are widely involved in cellular inflammation regulation, energy metabolism and oxidative stress. The effects of SIRTs on immune cells are mainly reflected in the regulation of inflammatory pathways. This regulation helps balance the inflammatory response and may lessen cell damage and organ dysfunction in sepsis. In terms of energy metabolism, SIRTs can play a role in immunophenotypic transformation by regulating cell metabolism, improve mitochondrial function, increase energy production, and maintain cell energy balance. SIRTs also regulate the production of reactive oxygen species (ROS), protecting cells from oxidative stress damage by activating antioxidant defense pathways and maintaining a balance between oxidants and reducing agents. Current studies have shown that several potential drugs, such as Resveratrol and melatonin, can enhance the activity of SIRT. It can help to reduce inflammatory response, improve energy metabolism and reduce oxidative stress, showing potential clinical application prospects for the treatment of sepsis. This review focuses on the regulation of SIRT on inflammatory response, energy metabolism and oxidative stress of immune cells, as well as its important influence on multiple organ dysfunction in sepsis, and discusses and summarizes the effects of related drugs and compounds on reducing multiple organ damage in sepsis through the pathway involving SIRTs. SIRTs may become a new target for the treatment of sepsis and its resulting organ dysfunction, providing new ideas and possibilities for the treatment of this life-threatening disease.

Multiplexed in-situ mutagenesis driven by a dCas12a-based dual-function base editor.

Mutagenesis driving genetic diversity is vital for understanding and engineering biological systems. However, the lack of effective methods to generate in-situ mutagenesis in multiple genomic loci combinatorially limits the study of complex biological functions. Here, we design and construct MultiduBE, a dCas12a-based multiplexed dual-function base editor, in an all-in-one plasmid for performing combinatorial in-situ mutagenesis. Two synthetic effectors, duBE-1a and duBE-2b, are created by amalgamating the functionalities of cytosine deaminase (fromhAPOBEC3A orhAID*Δ ), adenine deaminase (fromTadA9), and crRNA array processing (fromdCas12a). Furthermore, introducing the synthetic separator Sp4 minimizes interference in the crRNA array, thereby facilitating multiplexed in-situ mutagenesis in both Escherichia coli and Bacillus subtilis. Guided by the corresponding crRNA arrays, MultiduBE is successfully employed for cell physiology reprogramming and metabolic regulation. A novel mutation conferring streptomycin resistance has been identified in B. subtilis and incorporated into the mutant strains with multiple antibiotic resistance. Moreover, surfactin and riboflavin titers of the combinatorially mutant strains improved by 42% and 15-fold, respectively, compared with the control strains with single gene mutation. Overall, MultiduBE provides a convenient and efficient way to perform multiplexed in-situ mutagenesis.

Sodium alginate-polyethylene glycol paste loaded with zinc-doped tricalcium phosphate particles for the treatment of dentin hypersensitivity

β-tricalcium phosphate (β-TCP) has been widely applied in tissue engineering due to its excellent biocompatibility, degradability, and ability to induce mineralization. Zinc ion (Zn2+) displays excellent antibacterial properties and a vital role in regulating cell metabolism. In this context, the incorporation of Zn2+ into β-TCP to prepare Zn-doped β-tricalcium phosphate (Zn-β-TCP), emerges as a promising strategy for treating dentin hypersensitivity. However, delivering Zn-β-TCP effectively to the dentin surface for inducing mineralization of dentinal tubules remains a considerable challenge. In this study, we developed a sodium alginate-polyethylene glycol paste loaded with Zn-β-TCP particles, aiming to deliver Zn-β-TCP to the dentin surface for inducing mineralization. Zn-β-TCP particles were synthesized by the hydrothermal method and were combined with a sodium alginate-polyethylene glycol solution to create the Zn-β-TCP/sodium alginate/polyethylene glycol (Zn-β-TCP/SA/PEG) paste. In vitro experiments demonstrated that Zn-β-TCP could induce mineralization, exert good biocompatibility and antibacterial activity, promote dentin differentiation of dental pulp stem cells. Furthermore, Zn-β-TCP/SA/PEG exhibited excellent viscosity and effectively prompted the formation of a mineralized layer on dentin surfaces, successfully blocking dentinal tubules. Taken together, the present study demonstrated the potential of the Zn-β-TCP/SA/PEG paste as a promising therapeutic material for the treatment of dentin hypersensitivity.

Abstract 1955: Novel long-acting covalent PI3Kα inhibitors boost potential action in cancer

Abstract Phosphoinositide 3-kinase (PI3K) is a key regulator of cell proliferation, survival, and metabolism. Hotspot mutations in the PIK3CA gene constitutively activate the catalytic subunit of the PI3Kα isoform and are found in 10-30% of solid tumors. The development of PI3K pathway inhibitors has been hampered by poor drug tolerance and release of negative feedback loops, leading to rapid reactivation of signaling in response to reversible inhibitors. To remedy these challenges, we developed highly selective covalent PI3Kα inhibitors that irreversibly bind to a non-conserved cysteine (C862) located 11 Å outside the ATP-binding site. Here we present the properties of an optimized drug-like covalent lead, dubbed compound 9, and describe the generation of a biotinylated probe developed to be used in conjunction with compound 9 to monitor PI3Kα target occupancy in relation to downstream PI3K signaling outputs. Biochemical investigations of compound 9 using TR-FRET assays showed high affinity binding (Ki), high reaction rates (kinact) for covalent bond formation with PI3Kα, and negligible off-target reactivity. Cellular NanoBRET assays revealed that compound 9 diffuses three times more rapidly into cells as compared to BYL719 (alpelisib), and leads to rapid and potent on-target engagement. Covalent bond formation to residue C862 of PI3Kα was further confirmed by X-ray crystallography. In PIK3CA mutant cancer cell lines, covalent binding of PI3Kα occurred at low nanomolar concentrations and led to persistent inhibition of Akt/PKB phosphorylation for more than 72 hours after drug removal. Notably, investigation of PI3Kα re-synthesis after labeling with compound 9 showed a negligible reappearance in cancer cell lines, which indicates that persistent suppression of PI3Kα signaling by compound 9 results in a much longer half-life for PI3Kα than previously reported. The irreversible inactivation of PI3Kα by compound 9 provides a marked gain in growth inhibition potency (10-600-fold) in PIK3CA mutant cancer cell lines in comparison to clinical reversible PI3Kα inhibitors and allows for intermittent dosing without compromising efficacy. These data collectively demonstrate that compound 9 enables precise and selective targeting of PI3Kα with high potency and long-lasting efficacy in cancer models. The new class of irreversible PI3Kα inhibitors have a unique pharmacology among PI3K inhibitors characterized by strong decoupling of drug exposure from efficacy which may provide opportunities to lower treatment burden in patients. Citation Format: Theodora A. Constantin, Lukas Bissegger, Erhan Keleş, Luka Raguž, Clara Orbegozo, Thorsten Schaefer, Isobel Barlow-Busch, John E. Burke, Chiara Borsari, Matthias P. Wymann. Novel long-acting covalent PI3Kα inhibitors boost potential action in cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1955.