Protein Synthesis Research Articles

Genetics of conditional extended mycelial cell viability of Streptomyces minutiscleroticus in deep starvation phase implicates the involvement of (p)ppGpp, clpX, and a histidine kinase sasA

Bacterial lifespan ranges from a few hours to geological timescales. The prolonged survival trait under extreme energy starvation is essential for the perpetuation of their existence. The theme for long-term survival [long-term stationary phase (LTSP)] in the non-growing state may be dependent on the diversity in the environmental niche and the lifestyle of the bacteria, exemplified by longevity studies, albeit few, with model organisms. In the present study, we characterized the LTSP of mycelial cells of Streptomyces Minutiscleroticus, which remain metabolically active, demonstrate ongoing protein synthesis—killed by protein synthesis inhibitors—and remarkably by the cell-wall synthesis inhibitors, vancomycin, and ampicillin, suggesting “growth.” Their rapid turnover is also evident in ~10-fold loss of colony-forming unit (CFU) over a year, suggesting that for the death of one “old” cell, slightly less than one “new” cell is born. This longevity is consequent to (i) induction of the gene expression program effected by non-metabolizable, non-ionic osmolyte, sucrose, thus conditional, and (ii) possibly rendering this carbon utilizable by the production of a slow hydrolytic activity generating glucose, reinforcing the relevance of low-level energy resource for long term survival in the starvation phase. The viability parameters of LTSP cells measured through up to 90 days suggest that the stationary phase transitioning into LTSP following nutrient exhaustion is nearly quantitative. Expectedly, the viability in LTSP is (p)ppGpp/RelA dependent. Whereas mutation in chaperone clpX, negatively affects survival in stationary phase, overexpression of signal sensor-transducer histidine kinase, SasA8, enhances cell survivability. The relevance of longevity functions identified here requires further deduction of the genetic program.

RiboSeq.Org: an integrated suite of resources for ribosome profiling data analysis and visualization

Abstract Ribosome profiling (Ribo-Seq) has revolutionised our understanding of translation, but the increasing complexity and volume of Ribo-Seq data present challenges for its reuse. Here, we formally introduce RiboSeq.Org, an integrated suite of resources designed to facilitate Ribo-Seq data analysis and visualisation within a web browser. RiboSeq.Org comprises several interconnected tools: GWIPS-viz for genome-wide visualisation, Trips-Viz for transcriptome-centric analysis, RiboGalaxy for data processing and the newly developed RiboSeq data portal (RDP) for centralised dataset identification and access. The RDP currently hosts preprocessed datasets corresponding to 14840 sequence libraries (samples) from 969 studies across 96 species, in various file formats along with standardised metadata. RiboSeq.Org addresses key challenges in Ribo-Seq data reuse through standardised sample preprocessing, semi-automated metadata curation and programmatic information access via a REST API and command-line utilities. RiboSeq.Org enhances the accessibility and utility of public Ribo-Seq data, enabling researchers to gain new insights into translational regulation and protein synthesis across diverse organisms and conditions. By providing these integrated, user-friendly resources, RiboSeq.Org aims to lower the barrier to reproducible research in the field of translatomics and promote more efficient utilisation of the wealth of available Ribo-Seq data.

Spatial and Single‐Cell Transcriptomics Unraveled Spatial Evolution of Papillary Thyroid Cancer

AbstractRecurrence and metastasis are the major issues for papillary thyroid cancer (PTC). Current morphological and molecular classification systems are not satisfied for PTC diagnosis due to lacking variant‐specific morphological criteria and high signal‐to‐noise in mutation‐based diagnosis, respectively. Importantly, intratumor heterogeneity is largely lost in current molecular classification system, which can be resolved by single cell RNA sequencing (scRNA‐seq). However, scRNA‐seq loses spatial information and morphological features. Herein, scRNA‐seq is integrated and spatially‐resolved transcriptomics (SRT) to elaborate the mechanisms underlying the spatial heterogeneity, malignancy and metastasis of PTCs by associating transcriptome and local morphology. This results demonstrated that PTC cells evolved with multiple routes, driven by the enhanced aerobic metabolism and the suppressed mRNA translation and protein synthesis and the involvement of cell–cell interaction. Two curated malignant and metastatic footprints can discriminate PTC cells from normal thyrocytes. Ferroptosis resistance contributed to PTC evolution. This results will advance the knowledge of intratumor spatial heterogeneity and evolution of PTCs at spatial and single‐cell levels, and propose better diagnostic strategy.

Abstract PR002: Hypoxia-induced epigenetic changes coordinate transcription start site selection and translational control through remodeling of 5’UTRs

Abstract Adaptation to hypoxia enhances cancer cell malignancy and negatively impacts patient outcomes. Reprogramming of mRNA translation is an essential component of the hypoxia-adaptive response. During hypoxia, cells undergo a global decrease in protein synthesis. However, translation of subsets of transcripts encoding stress-response, survival and stemness factors is increased. This selective regulation is thought to be governed largely via the interactions between specific mRNA features and remodeling of the translational apparatus. However, our understanding of the mechanisms that govern translational perturbations under hypoxia remains incomplete. Here, we interrogated the effects of hypoxia on global changes in histone methylation and transcription start site (TSS) selection, coupled with monitoring corresponding alterations in total mRNA levels and translation efficiencies on a genome-wide scale in T47D breast cancer cells and H9 human embryonic stem cells. This revealed widespread epigenetic alterations leading to TSS switching and extensive remodeling of 5’UTRs, and allowed us to map the impact of specific 5’UTR features on translation efficiency under hypoxia. Pyruvate Dehydrogenase Kinase 1 (PDK1), a key enzyme in orchestrating metabolic adaption to hypoxia, undergoes TSS switching leading to increased availability of efficiently translated 5’UTR isoforms, and we show that this effect is coordinated at an epigenetic level. Therefore, our findings uncover a mechanism driving translational reprogramming under hypoxia, whereby alterations in translational apparatus are orchestrated with epigenetic perturbations that result in 5’UTR remodeling of the transcriptome. Citation Format: Kathleen Watt, Bianca Dauber, Krzysztof J Szkop, Laura Lee, Predrag Jovanovic, Shan Chen, Laia Masvidal, Kristofersson Tandoc, Ranveer Palia, Ivan Topisirovic, Ola Larsson, Lynne-Marie Postovit. Hypoxia-induced epigenetic changes coordinate transcription start site selection and translational control through remodeling of 5’UTRs [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: RNAs as Drivers, Targets, and Therapeutics in Cancer; 2024 Nov 14-17; Bellevue, Washington. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(11_Suppl):Abstract nr PR002.

Abstract B001: CircRNA-derived neoantigen identification in cancer vaccine development

Abstract Immunotherapy has been a popular topic in combating cancer for its great performance in specificity, versatility and durability recently. Cancer vaccines targeting neoantigens have shown clinical efficacy against cancer, eliciting long-lasting immune response and offering a more selective therapeutic approach with less side effects. However, rare mutation rates and low expression levels of neoantigen make it challenging to identify suitable neoantigens. Traditionally, researchers focus on the canonical mRNA transcriptome and proteome to find potential targets. Recent studies suggest that exploring the non-canonical transcriptome and proteome, particularly circular RNAs (circRNAs), can expand the search. CircRNAs, endogenously formed by the unique back-splicing events during pre-RNA processing, can serve as templates for protein synthesis. Some of these non-canonical peptides are specifically expressed in cancer cells, making circRNAs a valid source for neoantigen discovery. We have developed high-throughput circRNA reporter screening methods and mass spectrometry-based peptidomic workflow to pinpoint translating circRNAs and their derived peptides. Using these techniques, we have identified circRNA-derived neoantigens in breast cancer (BC) cell lines that can be used as possible targets for cancer vaccines. These circRNA-derived neoantigens are immunogenic and can trigger dendritic cell (DC) maturation and T cell activation in vitro. Next, we will test these findings by transferring to in vivo mouse system. We will assess cancer vaccine efficacy by targeting the neoantigens using syngeneic mouse tumor models. Our long- term goal is to apply the circRNA neoantigen identification technology to BC patient samples to facilitate cancer vaccine development and improve cancer immunotherapy. Our work will demonstrate the potential of circRNA-derived non canonical neoantigens in cancer vaccines, serving as a crucial first step to prove their effectiveness in therapy. By expanding our search beyond the traditional transcriptome and proteome, we will explore new targets and transform the neoantigen-based treatment. This innovative effort shifts the current understanding of neoantigen sources and opens up new possibilities for targeted cancer therapy strategies. Citation Format: Yi-Cian Zheng, Chun-Kan Chen. CircRNA-derived neoantigen identification in cancer vaccine development [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: RNAs as Drivers, Targets, and Therapeutics in Cancer; 2024 Nov 14-17; Bellevue, Washington. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(11_Suppl):Abstract nr B001.

The role of anti-aging approaches in managing hypogonadism in sedentary older males

IntroductionWith thirty percent of the world’s population not getting enough exercise, Worldwide, physical inactivity ranks as one of the most common causes of premature mortality. Rapid drops in physical activity, decreased mobility, and early morbidity are aging characteristics. As the population over 80 continues to rise, aging raises the danger of age-related illnesses and changes in hormone release.AimUnderstanding the aging process is useful in developing pharmacological therapies and identifying therapeutic targets for age-related testosterone deficiency. Therefore, this study’s purpose is to present a thorough evaluation of the effects of anti-aging strategies on testosterone levels in older, inactive men.MethodsA literature search was completed for clinical and preclinical studies published in English between 2014 and 2024 related to age, sedentary life, testosterone, and anti-aging strategies.ResultsA sedentary lifestyle and low testosterone are linked to a vicious cycle. A sedentary lifestyle lowers testosterone levels, which leads to depression, exhaustion, low energy, and weakened bone and muscle strength. These effects exacerbate the detrimental consequences of aging and physical inactivity. Anti-aging techniques can prevent and treat age-related diseases, including calorie restriction, a balanced diet, regular exercise, weight control, diabetes management, and quitting smoking. Regular exercise raises total testosterone, free testosterone, and muscle steroidogenesis. In older men, testosterone replacement treatment increases bone density, cholesterol, protein synthesis, strength, erectile function, sexual desire, and general cognitive performance. However, some studies suggest dehydroepiandrosterone supplementation may provide health improvements without negative effects, potentially reversing arterial aging and reducing cardiovascular disease risk.ConclusionThis article evaluates the prospects for anti-aging procedures to assist in reducing the adverse effects of aging and physical inactivity in men.

Extending the G1 phase improves the production of lipophilic compounds in yeast by boosting enzyme expression and increasing cell size

Cell phase engineering can significantly impact protein synthesis and cell size, potentially enhancing the production of lipophilic products. This study investigated the impact of G1 phase extension on resource allocation, metabolic functions, and the unfolded protein response (UPR) in yeast, along with the potential for enhancing the production of lipophilic compounds. In brief, the regulation of the G1 phase was achieved by deleting CLN3 (G1 cyclin) in various yeast strains. This modification resulted in a 83% increase in cell volume, a 76.9% increase in dry cell weight, a 82% increase in total protein content, a 41% increase in carotenoid production, and a 159% increase in fatty alcohol production. Transcriptomic analysis revealed significant upregulation of multiple metabolic pathways involved in acetyl-CoA (acetyl coenzyme A) synthesis, ensuring an ample supply of precursors for the synthesis of lipophilic products. Furthermore, we observed improved protein synthesis, attributed to UPR activation during the prolonged G1 phase. These findings not only enhanced our understanding and application of yeast’s capacity to synthesize lipophilic compounds in applied biotechnology but also offered unique insights into cellular behavior during the modified G1 phase, particularly regarding the UPR response, for basic research. This study demonstrates the potential of G1 phase intervention to increase the yield of hydrophobic compounds in yeast, providing a promising direction for further research.

Mimicking Osteoid 3D Porous Dense Microfiber Silk Fibroin Embedded Poly(vinyl alcohol) Scaffold for Alveolar Ridge Preservation

Abstract Alveolar ridge loss presents difficulties for implant placement and stability. To address this, alveolar ridge preservation (ARP) is required to maintain bone and avoid the need for ridge augmentation using socket grafting. In this study, a scaffold for ARP was created by fabricating a 3D porous dense microfiber silk fibroin (mSF) embedded in poly(vinyl alcohol) (PVA), which mimics the osteoid template. The research utilized a freeze-thawing technique to create a mimicked osteoid 3D porous scaffold by incorporating different amounts of mSF into the PVA, namely, 1%, 3%, 5%, and 7%. Subsequently, a 3D profilometer machine and a scanning electron microscope (SEM) were employed to examine the morphology and size of the mSF and the mimicked osteoid 3D porous scaffold in all groups. Thermal characteristics and crystalline structure were analyzed before assessing the water contact angle, swelling behavior, degradation, and mechanical properties. The experiment evaluated the biological performance of the mimicked osteoid 3D porous scaffold by examining the efficacy of osteoblast cell adhesion, proliferation, viability, protein synthesis, alkaline phosphatase (ALP) activity, and calcium synthesis. Finally, the ability of osteoblast cells to regulate the osteoid matrix deposition on the osteoid 3D porous scaffold was assessed by mimicking the dynamic bone environment using rat mesenchymal stem cells (RMSC). The findings suggest that incorporating mSF into PVA enhances the interconnective pore size, crystalline structure, and thermal behavior of the mimicked osteoid 3D porous scaffold. The hydrophilicity of PVA decreased with an increase in the proportion of mSF, while a higher proportion of mSF resulted in increased swelling and mechanical characteristics. Incorporating a greater proportion of mSF, specifically 5% and 7%, led to a reduced rate of degradation. The addition of 5% mSF to the PVA 3D porous scaffold resulted in remarkable biological properties and excellent osteoconductive activity.

Consideration of the role of protein quality in determining dietary protein recommendations

The quality of a dietary protein refers to its ability to provide the EAAs necessary to meet dietary requirements. There are 9 dietary amino acids that cannot be metabolically produced in the body and therefore must be consumed as part of the diet to avoid adverse metabolic consequences. These essential amino acids (EAAs) serve a variety of roles in the body. The amount and profile of the dietary EAAs relative to the individual EAA requirements and the digestibility of the dietary protein are the key factors that determine its quality. Currently the Digestible Indispensable Amino Acid Score (DIAAS) is the best available approach to quantifying protein quality. The most prominent metabolic role of dietary EAAs is to stimulate protein synthesis by serving as signals to activate molecular mechanisms responsible for the initiation of protein synthesis and, most importantly, to provide the necessary precursors for the synthesis of complete proteins. Current dietary recommendations generally do not consider protein quality. Accounting for protein quality in dietary patterns can be accomplished while staying within established ranges for dietary protein consumption. Poor protein quality can be compensated for to some extent by eating more low-quality protein, but to be effective (“complementary”) the limiting EAA must differ between the low-quality protein and the base diet to which it is being supplemented. Adding a high-quality protein to a dietary pattern based on low-quality protein is more effective in meeting EAA goals than increasing the amount of low-quality protein, even if the low-quality proteins are complementary. Further, reliance entirely on low-quality protein food sources, particularly in circumstances that may benefit from a level of dietary EAAs greater than minimal requirements, is likely to include excessive caloric consumption. While protein consumption in high-income nations is generally perceived to be adequate or even excessive, assessment of dietary patterns indicates that a significant percentage of individuals may fall short of meeting optimal levels of EAA consumption, especially in circumstances such as aging in which the optimal EAA consumption is greater than basal values for healthy young individuals. The case is made that protein quality is an important consideration in meeting EAA requirements.

New insights into the mechanisms of red blood cell enucleation: From basics to clinical applications

AbstractBackgroundRed blood cell (RBC) enucleation is a crucial step in the process of erythropoiesis. By removing the nucleus, RBCs gain greater flexibility, enabling them to traverse narrow capillaries with ease, thereby enhancing the efficiency of oxygen and carbon dioxide transport. This transformation underscores the intricate balance between cellular structure and function essential for maintaining homeostasis.TopicThis review delves into the multifaceted enucleation process, outlining its complex steps that encompass protein sorting, vesicle trafficking, cytoskeletal remodeling, and apoptosis regulation, while also exploring the potential of enhancing the enucleation rate of RBCs in vitro. We emphasize the intricate regulation of this process, which is orchestrated by multiple factors. This includes transcription factors that meticulously guide protein synthesis and sorting through the modulation of gene expression, as well as non‐coding RNAs that play a pivotal role in post‐transcriptional regulation during various stages of RBC enucleation. Additionally, macrophages participate in the enucleation process by engulfing and clearing the extruded nuclei, further ensuring the proper development of RBCs. Although many studies have deeply explored the molecular mechanisms of enucleation, the roles of apoptosis and anti‐apoptotic processes in RBC enucleation remain incompletely understood.ImplicationIn this review, we aim to comprehensively summarize the RBC enucleation process and explore the progress made in ex vivo RBC generation. In the future, a deeper understanding of the enucleation process could provide significant benefits to patients suffering from anemia and other related conditions.

Distinct effects of CDK8 module subunits on cellular growth and proliferation in Drosophila

The Mediator complex plays a pivotal role in facilitating RNA polymerase II-dependent transcription in eukaryotes. Within this complex, the CDK8 kinase module (CKM), comprising CDK8, Cyclin C (CycC), Med12, and Med13, serves as a dissociable subcomplex that modulates the activity of the small Mediator complex. Genetic studies in Drosophila have revealed distinct phenotypes associated with mutations in CKM subunits, but the underlying mechanisms have remained unclear. Using Drosophila as a model, we generated transgenic strains to individually or simultaneously deplete the four CKM subunits in all possible combinations, uncovering unique phenotypes in the eyes and wings. Depletion of CDK8-CycC enhanced E2F1 target gene expression and promoted cell-cycle progression, whereas Med12-Med13 depletion had no significant impact on these processes. Instead, depleting Med12-Med13 altered the expression of ribosomal protein genes and fibrillarin, reduced nascent protein synthesis, indicating a severe reduction in ribosome biogenesis and cellular growth compared to the loss of CDK8-CycC. These findings reveal distinct in vivo roles for CKM subunits, with Med12-Med13 disruption having a more pronounced effect on ribosome biogenesis and protein synthesis than CDK8-CycC loss.

Systematic genetic characterization of the human PKR kinase domain highlights its functional malleability to escape a poxvirus substrate mimic

Evolutionary arms races can arise at the contact surfaces between host and viral proteins, producing dynamic spaces in which genetic variants are continually pursued. However, the sampling of genetic variation must be balanced with the need to maintain protein function. A striking case is given by protein kinase R (PKR), a member of the mammalian innate immune system. PKR detects viral replication within the host cell and halts protein synthesis to prevent viral replication by phosphorylating eIF2α, a component of the translation initiation machinery. PKR is targeted by many viral antagonists, including poxvirus pseudosubstrate antagonists that mimic the natural substrate, eIF2α, and inhibit PKR activity. Remarkably, PKR has several rapidly evolving residues at this interface, suggesting it is engaging in an evolutionary arms race, despite the surface’s critical role in phosphorylating eIF2α. To systematically explore the evolutionary opportunities available at this dynamic interface, we generated and characterized a library of 426 SNP-accessible nonsynonymous variants of human PKR for their ability to escape inhibition by the model pseudosubstrate inhibitor K3, encoded by the vaccinia virus gene K3L. We identified key sites in the PKR kinase domain that harbor K3-resistant variants, as well as critical sites where variation leads to loss of function. We find K3-resistant variants are readily available throughout the interface and are enriched at sites under positive selection. Moreover, variants beneficial against K3 were also beneficial against an enhanced variant of K3, indicating resilience to viral adaptation. Overall, we find that the eIF2α-binding surface of PKR is highly malleable, potentiating its evolutionary ability to combat viral inhibition.

Systematic genetic characterization of the human PKR kinase domain highlights its functional malleability to escape a poxvirus substrate mimic

Evolutionary arms races can arise at the contact surfaces between host and viral proteins, producing dynamic spaces in which genetic variants are continually pursued. However, the sampling of genetic variation must be balanced with the need to maintain protein function. A striking case is given by protein kinase R (PKR), a member of the mammalian innate immune system. PKR detects viral replication within the host cell and halts protein synthesis to prevent viral replication by phosphorylating eIF2α, a component of the translation initiation machinery. PKR is targeted by many viral antagonists, including poxvirus pseudosubstrate antagonists that mimic the natural substrate, eIF2α, and inhibit PKR activity. Remarkably, PKR has several rapidly evolving residues at this interface, suggesting it is engaging in an evolutionary arms race, despite the surface’s critical role in phosphorylating eIF2α. To systematically explore the evolutionary opportunities available at this dynamic interface, we generated and characterized a library of 426 SNP-accessible nonsynonymous variants of human PKR for their ability to escape inhibition by the model pseudosubstrate inhibitor K3, encoded by the vaccinia virus gene K3L. We identified key sites in the PKR kinase domain that harbor K3-resistant variants, as well as critical sites where variation leads to loss of function. We find K3-resistant variants are readily available throughout the interface and are enriched at sites under positive selection. Moreover, variants beneficial against K3 were also beneficial against an enhanced variant of K3, indicating resilience to viral adaptation. Overall, we find that the eIF2α-binding surface of PKR is highly malleable, potentiating its evolutionary ability to combat viral inhibition.

TUDY OF CHRONIC TOXICITY OF AN IMPROVED A-SILICONE IMPRESSION MATERIAL PRODUCED IN UKRAINE

The objective of this study is to evaluate the potential toxic effects of an improved A-silicone impression material with decorative properties on the organs and mucous membranes of laboratory animals. Materials and Methods The experiment was conducted on white laboratory rats aged 9 months and weighing 230–285 g. Findings indicate that prolonged contact (30 days) with the material does not result in significant changes in the function of major organ systems in these laboratory rats. Results. A single exposure of laboratory rats to A-silicone impression material with disinfectant properties did not cause significant changes in the physiological state of the animals. Weights of internal organs, including the liver, spleen, heart, and adrenal glands, remained within normal limits, indicating that the material had no toxic effects. The analysis of the peripheral blood composition did not reveal any abnormalities in the number of red blood cells, leukocytes, hemoglobin and other cellular components. The functional state of the liver and kidneys, including the activity of the enzymes AlаT and AсаT, levels of total protein, albumin, creatinine and urea, remained stable and did not change under the influence of the material. There was also no effect on carbohydrate metabolism. No abnormalities in protein synthesis and nitrogen excretion functions were detected, which confirms the safety of the material during the 30-day observation. Conclusion. It was established that this material in the tested dose does not affect the enzyme-synthetic function of the liver and does not exhibit cytolytic effects. The material was found to have no toxic impact on liver function with prolonged use, nor does it cause statistically significant deviations in the measured indicators between the control and experimental groups. The absence of sugar, ketones, and protein in the urine indicates no adverse effect on the renal nitrogen-excreting and saluretic functions, as well as on the vital organs of the rats.

Nanopore-Based Sequencing of the Full-Length Transcriptome of Male and Female Cleavage-Stage Embryos of the Chinese Mitten Crab (Eriocheir sinensis)

The cleavage stage plays a crucial role in embryo development, characterized by a swift surge in cell proliferation alongside the accurate genetic material transmission to offspring. To delve into the characteristics of sex development during the cleavage stage of embryos, we generated the full-length transcriptome of Eriocheir sinensis male and female cleavage-stage embryos using Oxford Nanopore Technologies (ONT). Notably, this investigation represents the first sequencing effort distinguishing between genders in E. sinensis embryos. In the transcriptome structure analysis, male and female cleavage-stage embryos, while not clustered, exhibited a comparable frequency of alternative splicing (AS) occurrences. We also successfully identified 2875 transcription factors (TFs). The quantitative analysis showed the top 150 genes, in which the highly expressed genes in male embryos predominantly related to protein synthesis and metabolism. Further investigation unveiled 500 differentially expressed genes (DEGs), of which 7 male-biased ribosomal protein genes (RPGs) were particularly noteworthy and further confirmed. These analyses suggest that there may be a more active protein synthesis process in male E. sinensis cleavage-stage embryos. Furthermore, among the 2875 identified TFs, we predicted that 18 TFs could regulate the differentially expressed RPGs, with most TFs belonging to the zf-C2H2 and Homeobox families, which are crucial for embryonic development. During the cleavage stage of E. sinensis, the differential RPGs between genders were intricately linked to energy metabolism. We proposed that these RPGs exert regulatory effects on gene expression in E. sinensis, thereby regulating the difference of development between male and females. Our research sheds light on the developmental mechanisms of E. sinensis during the embryo stage and establishes a groundwork for a deeper understanding of sex development in E. sinensis. The results also provide comprehensive full-length transcriptome data for future gene expression and genetic studies in E. sinensis.

Respiratory Outcomes of Interrupted Modulator Therapies in Children With Cystic Fibrosis

ABSTRACTBackgroundCystic fibrosis (CF) is a multisystemic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, resulting in defective synthesis or function of the CFTR protein. Historically, CF treatment focused on managing symptoms and complications. Fortunately, modulator drugs are now available to directly target the defective CFTR protein. However, in some countries, such as Turkey, these drugs are not covered by social insurance. Consequently, many CF patients face barriers to accessing modulatory therapies or must interrupt their treatment. This study demonstrates the impact of interrupting modulator therapy on pulmonary function, emphasizing the need for uninterrupted continuous treatment.MethodsIn this study, 39 CF patients receiving elexacaftor‐tezacaftor‐ivacaftor (ETI) at our clinic were retrospectively analyzed. Among the patients, 18 experienced one or more interruptions, ranging from 15 to 210 days during ETI treatment. We analyzed pulmonary function test results from 27 interruption periods.ResultsAt the beginning of the interruption, the mean percent predicted FEV1 (ppFEV1) was 69.59% ± 25.87%, which decreased to 64.96% ± 24.52% by the end of the interruption. There was a significant decrease with a mean change of 4.62 ± 8.49 (p = 0.008). However, no significant correlation was found between the interruption duration and FEV1 change.ConclusionOur results demonstrate that pulmonary functions are adversely affected by interruption periods, regardless of their duration. Even short interruptions have a significant impact on pulmonary functions. This underscores the need for uninterrupted continuation of modulatory treatment and for improved policies to ensure equitable access to treatment.

Bone loss with aging is independent of gut microbiome in mice

Emerging evidence suggests a significant role of gut microbiome in bone health. Aging is well recognized as a crucial factor influencing the gut microbiome. In this study, we investigated whether age-dependent microbial change contributes to age-related bone loss in CB6F1 mice. The bone phenotype of 24-month-old germ-free (GF) mice was indistinguishable compared to their littermates colonized by fecal transplant at 1-month-old. Moreover, bone loss from 3 to 24-month-old was comparable between GF and specific pathogen-free (SPF) mice. Thus, GF mice were not protected from age-related bone loss. 16S rRNA gene sequencing of fecal samples from 3-month and 24-month-old SPF males indicated an age-dependent microbial shift with an alteration in energy and nutrient metabolism potential. An integrative analysis of 16S predicted metagenome function and LC-MS fecal metabolome revealed an enrichment of protein and amino acid biosynthesis pathways in aged mice. Microbial S-adenosyl methionine metabolism was increased in the aged mice, which has previously been associated with the host aging process. Collectively, aging caused microbial taxonomic and functional alteration in mice. To demonstrate the functional importance of young and old microbiome to bone, we colonized GF mice with fecal microbiome from 3-month or 24-month-old SPF donor mice for 1 and 8 months. The effect of microbial colonization on bone phenotypes was independent of the microbiome donors’ age. In conclusion, our study indicates age-related bone loss occurs independent of gut microbiome.

Integrated Profiling Identifies Long-Term Molecular Consequences of Prenatal Dexamethasone Treatment in the Rat Brain—Potential Triggers of Depressive Phenotype and Cognitive Impairment

Abstract Prenatal excess of glucocorticoids (GCs) is considered to be one of the highly impacting factors contributing to depression development. Although GCs are crucial for normal fetal development and their administration (mainly dexamethasone, DEX) is a life-saving procedure for those at risk of preterm delivery, exposure to excess levels of GCs during pregnancy can yield detrimental consequences. Therefore, we aimed to systematically investigate the brain molecular alterations triggered by prenatal DEX administration. We used a rat model of depression based on prenatal exposure to DEX and performed integrative multi-level methylomic, transcriptomic, and proteomic analyses of adult rats’ brains (i.e., frontal cortex (FCx) and hippocampus (Hp)) to identify the outcomes of DEX action. Each of the investigated levels was significantly affected by DEX in the long-term manner. Particularly, we found 200 CpG islands to be differentially methylated in the FCx and 200 in the Hp of prenatally DEX-treated rats. Global transcriptomic analysis uncovered differential expression of transcripts mostly in FCx (271) and 1 in Hp, while proteomic study identified 146 differentially expressed proteins in FCx and 123 in Hp. Among the identified enriched molecular networks, we found altered pathways involved in synaptic plasticity (i.e., cAMP, calcium, and Wnt signaling pathways or tight junctions and adhesion molecules), which may contribute to cognitive impairment, observed in DEX-treated animals. Moreover, in the FCx, DEX administration in the prenatal period downregulates the expression of ribosome protein genes associated both with large and small ribosomal subunit assembly which can lead to a global decrease in translation and protein synthesis processes and, indirectly, alterations in the neurotransmission process.

PATHOPHYSIOLOGICAL AND STRUCTURAL PECULIARITIES OF CARDIAC FIBROSIS DEVELOPMENT IN ATRIAL FIBRILLATION

Introduction. In recent years, the study of the pathogenesis of atrial fibrillation (AF) and its complications resulting from this condition has drawn substantial attention from cardiologists. A comprehensive understanding of this issue is essential for investigating the structural and functional disturbances occurring in the heart during AF. These data are also important for developing novel therapies aimed at preventing the onset and progression of cardiac fibrosis. The aim of this study is to identify the primary pathways that activate cardiac connective tissue cells involved in fibrosogenesis, to examine the structural characteristics of this pathological process, and to investigate the role of fibroblasts in initiating and progressing cardiac fibrosis. Materials and Methods. The primary data for this article were collected through an in-depth analysis of recent scientific literature, with a focus on studies published in the last 5–7 years. Results. A detailed review of primary sources reveals that this cardiological issue has only been partially explored. Findings indicate a close link between the pathophysiological and structural mechanisms of AF and numerous resulting complications, with cardiac fibrosis being a primary consequence. Two major forms of fibrous damage to atrial cardiomyocytes play a key role in the development of cardiac fibrosis associated with AF. This includes both reactive and reparative types of cardiac fibrosis, which develop concurrently in atrial fibrillation. These structural changes lead not only to damage and loss of cardiomyocytes but also to pathological remodeling of fibroblasts, the intercellular matrix, and the atria and ventricles. Disruptions in bioelectrical potential conduction are also observed. Activated fibroblasts play a central role in initiating cardiac fibrosis, with key stages of protein synthesis involved in atrial fibrosis now better understood. Specific intracellular signaling pathways, which present potential therapeutic targets for preventing cardiac fibrosis in AF treatment, have been identified. Conclusion. Atrial fibrillation and cardiac fibrosis are interdependent, with each potentially accelerating the progression of the other. These pathological processes are underpinned by significant structural and functional disruptions within cardiac cells and the intercellular matrix. Fibroblasts, myofibroblasts, and intensive fibrous tissue formation within the matrix are pivotal in the development of cardiac fibrosis. A preventive strategy targeting early intervention in cardiac fibrosis shows the greatest therapeutic promise.

MECHANISMS OF ACTION OF PROTEIN SHAKES IN NORMALIZING METABOLIC PROCESSES, THEIR ROLE IN IMPROVING GLYCEMIC CONTROL IN PATIENTS WITH TYPE 2 DIABETES, AND IN PREVENTING CARDIOVASCULAR DISEASES

This review article delves into the significance of protein shakes, particularly whey protein, in various health and fitness contexts. The primary focus is on their biochemical properties, metabolic benefits, and their role in supporting muscle mass, weight loss, and metabolic health. The article synthesizes findings from multiple studies to highlight the potential of protein shakes in improving glycemic control, reducing inflammation, and enhancing overall health, particularly for individuals with type 2 diabetes, obesity, and sarcopenia. The review also explores the effectiveness of protein shakes in athletic performance and recovery, as well as their impact on glucose metabolism and homeostasis. It underscores the necessity for further research to optimize the use and dosage of protein shakes for diverse populations to fully harness their benefits. Whey proteins are rich in essential amino acids, particularly leucine, which stimulates muscle protein synthesis via the mTOR pathway. This makes them highly effective in muscle building and recovery. Whey protein consumption enhances glycemic control by increasing insulin secretion and improving insulin sensitivity. Studies have shown significant reductions in fasting glucose levels and HbA1c in patients with type 2 diabetes. Protein shakes aid in weight loss by promoting satiety and increasing thermogenesis. They help maintain muscle mass during weight loss, which is crucial for sustaining metabolic rate. Clinical trials have demonstrated their efficacy in reducing body fat and improving metabolic markers. Whey protein, combined with resistance training, significantly improves muscle mass and strength in older adults, helping to prevent sarcopenia. This is essential for maintaining physical functionality and reducing the risk of falls and fractures. In the rehabilitation of patients with severe obesity, protein shakes are effective in reducing body weight, improving metabolic health, and maintaining muscle mass. They play a crucial role in comprehensive rehabilitation programs that include diet and physical exercise. Protein shakes support metabolic adaptations by preserving muscle mass and enhancing thermogenesis, which helps maintain a high metabolic rate and prevent weight regain. Whey proteins enhance muscle mass and strength, speed up recovery after training, and boost endurance. They also support the immune system and reduce oxidative stress, contributing to better overall athletic performance . Proteins shakes aid in regulating blood glucose levels and improving insulin sensitivity, which is crucial for preventing and managing diabetes. Their antioxidant and anti-inflammatory properties further enhance metabolic health.