A single-cell landscape of the regenerating spinal cord of zebrafish

JOURNAL/nrgr/04.03/01300535-202602000-00046/figure1/v/2025-05-05T160104Z/r/image-tiff Unlike mammals, zebrafish possess a remarkable ability to regenerate their spinal cord after injury, making them an ideal vertebrate model for studying regeneration. While previous research has identified key cell types involved in this process, the underlying molecular and cellular mechanisms remain largely unexplored. In this study, we used single-cell RNA sequencing to profile distinct cell populations at different stages of spinal cord injury in zebrafish. Our analysis revealed that multiple subpopulations of neurons showed persistent activation of genes associated with axonal regeneration post injury, while molecular signals promoting growth cone collapse were inhibited. Radial glial cells exhibited significant proliferation and differentiation potential post injury, indicating their intrinsic roles in promoting neurogenesis and axonal regeneration, respectively. Additionally, we found that inflammatory factors rapidly decreased in the early stages following spinal cord injury, creating a microenvironment permissive for tissue repair and regeneration. Furthermore, oligodendrocytes lost maturity markers while exhibiting increased proliferation following injury. These findings demonstrated that the rapid and orderly regulation of inflammation, as well as the efficient proliferation and redifferentiation of new neurons and glial cells, enabled zebrafish to reconstruct the spinal cord. This research provides new insights into the cellular transitions and molecular programs that drive spinal cord regeneration, offering promising avenues for future research and therapeutic strategies.

Artificial intelligence predicts pregnancy complications based on cytokine profiles

BACKGROUND

Early prediction of pregnancy complications is important for adequate and timely prevention, management, and reducing maternal/fetal pathogenesis.

OBJECTIVE

To study the prognostic value of cytokines as predictors of pregnancy complications using unbiased artificial intelligence/machine learning (AI/ML) methods.

METHODS

For this study, we used our previously published data on 127 women with pregnancy complications and 97 women with a history of normal delivery and undergoing a normal delivery. A panel of seven cytokines were analyzed from activated peripheral blood mononuclear cells (PBMC). AI/ML methods such as kNN, SVM, decision tree, and ensemble classification were applied to explore the possible use of AI/ML to compare and predict normal gestation and normal delivery as opposed to different pregnancy complications such as recurrent spontaneous miscarriage (RSM), preterm delivery (PTD), pregnancy-induced hypertension (PIH), and premature rupture of fetal membranes (PROM).

RESULTS

The study examined cytokine levels in various pregnancy conditions, revealing significant differences, particularly in the levels of IL-2 and IFN-γ, across age-matched comparisons. Additionally, binary classification tasks demonstrated notable accuracies and f-measures for methodologies such as Ensemble (Bagged), QDA, and SVM (Cubic), showcasing their effectiveness in distinguishing between normal delivery and different pregnancy complications.

CONCLUSION

The study provides a machine learning-based methodology for the prediction of pregnancy complications based on levels of cytokines produced by peripheral blood cells.

Cadmium treatment induces oxidative damage and apoptosis in vitro skeletal muscle cells

Cadmium is a prevalent environmental contaminant, and current research indicates that exposure to cadmium is a significant risk factor contributing to the increased incidence of sarcopenia. However, the precise mechanisms by which cadmium exposure leads to skeletal muscle damage remain to be fully elucidated. Utilizing an in vitro culture model of mouse C2C12 myoblasts, this study exposed cells to 0, 2, 4, and 8 μmol/L cadmium chloride for 24 hours to evaluate the cellular damage and explore the potential mechanisms. Our present data of this study demonstrate that cadmium treatment results in a reduction of C2C12 cell viability, an increased release of lactate dehydrogenase, and an imbalance in the oxidative-antioxidant system characterized by an excessive accumulation of reactive oxygen species, elevated malondialdehyde production, and decreased superoxide dismutase activity. Additionally, there is an upregulation of nuclear factor-erythroid 2-related factor 2, heme oxygenase-1, NAD(P)H quinone oxidoreductase 1, and glutamate-cysteine ligase catalytic subunit protein expression, along with a downregulation of superoxide dismutase 1 protein expression. Furthermore, cadmium exposure mediates an increase in cysteinyl aspartate specific proteinase-dependent apoptosis via the mitochondrial pathway, as indicated by an increased apoptosis rate, elevated Bcl-2 associated X protein and cysteinyl aspartate specific proteinase 3 protein expression, and a decreased expression of B-cell lymphoma-2 protein. Our findings elucidate the mechanisms of cadmium-induced cytotoxic damage in skeletal muscle cells from the perspectives of oxidative injury and apoptosis, thereby providing a theoretical basis for the prevention and treatment of cadmium toxicity.

Serendipitous discovery of intrathecal catheterization via the lumbosacral plexus in rats: A preliminary study

BACKGROUND

Intrathecal catheterization is essential for experimental studies, including drug delivery, stem cell therapy, and gene therapy, but it can sometimes be quite costly. Since traditional techniques, such as acute needle puncture and catheterization with or without laminectomy have shown varying success rates and procedural challenges, there is room for improvement.

NEW METHOD

This study presents an alternative approach to intrathecal catheterization via the lumbosacral plexus, which was serendipitously discovered during an attempt to cannulate the lymphatic system in male Lewis rats using a 0.010-inch microguidewire and a 1.3-F microcatheter with an over-the-wire technique under fluoroscopic guidance.

RESULTS

Intrathecal catheterization via the left L3 spinal nerve was achieved in 14 out of 17 rats (82 %). In one case, only the microguidewire was inserted, and in two cases, spinal nerve cannulation was unsuccessful. The median catheterization duration was 20 minutes. Accidental intrathecal placement was confirmed by postmortem micro-CT with iodinated contrast and dissection following isosulfan blue staining. No cerebrospinal fluid leakage was observed fluoroscopically during the procedure.

COMPARISON WITH EXISTING METHODS

This method demonstrated a higher cannulation rate and a procedural time comparable to traditional techniques such as non-laminectomized catheterization. Additionally, it eliminates the risk of cerebrospinal fluid leakage, a common complication in conventional catheterization approaches. However, motor function impairment due to nerve injury and the need for specialized fluoroscopy settings remain limitations.

CONCLUSIONS

This serendipitous discovery suggests that intrathecal catheterization via the lumbosacral plexus may be a feasible alternative approach in select cases.

Identification of VDAC1 as a mitochondria-related target of Duchenne muscular dystrophy based on bioinformatics analysis and in vitro experiments

BACKGROUND

Mitochondrial dysfunction is a well-recognized pathological feature of Duchenne Muscular Dystrophy (DMD). The potential regulatory role of mitochondria-related genes (MRGs) in DMD remains to be further explored.

METHODS

GEO datasets and MRGs were used to analysis mitochondrial scores and evaluate patients' immunological characteristics. Weighted gene co-expression network analysis, differentially expressed genes (DEGs) and MRGs were used to identify hub genes. A specific hub gene was selected, and the effects of this gene overexpression on a horse serum (HS) treated C2C12 cell in vitro model were investigated.

RESULTS

Mitochondrial score was decreased in DMD group. Significant differences were observed in 12 immune cell types in normal/DMD and high/low mitochondrial score groups. 9 hub genes were identified, with 7 validated. Among them, VDAC1 was selected for further study. Overexpression of VDAC1 in HS C2C12 myoblasts promoted cell proliferation, reduced apoptosis rate and the Bax expression (with concurrent Bcl2 upregulation), diminished LDH release to reduce cytotoxicity, decreased intracellular ROS levels to alleviate oxidative stress, inhibited the expression of autophagy (LC3) and atrophy (Atrogin-1 and MuRF-1) markers, and promoted differentiation.

CONCLUSION

In conclusion, VDAC1 may participate in the myoblast proliferation and myotube atrophy by influencing mitochondrial function, which may serve as a new target for DMD treatment.

Whole-transcriptome sequencing in neural and non-neural tissues of a mouse model identifies miR-34a as a key regulator in SMA pathogenesis

Spinal muscular atrophy (SMA) is a severe neurodegenerative disorder caused by deficiency of survival of motor neuron (SMN). While significant progress has been made in SMA therapy by rescuing SMN expression, limited knowledge about SMN downstream genes has hindered the development of alternative therapies. Here, we conducted whole-transcriptome sequencing of spinal cord, heart, and liver tissues of a severe SMA mouse model at early postnatal ages to explore critical coding and non-coding RNAs (ncRNAs). A large number of differentially expressed RNAs (DE-RNAs) were obtained, including 2,771 mRNAs, 382 microRNAs (miRNAs), 1,633 long ncRNAs, and 1,519 circular RNAs. Through in-depth data mining, we unveiled deregulation of miR-34a in all tissues. Analysis of competitive endogenous RNA networks of DE-RNAs identified multiple novel targets of miR-34a including Spag5 mRNA, lncRNA00138536, and circRNA007386. Further in vitro studies using mouse myoblast and human cardiomyocyte cell lines showed that knockdown of SMN upregulated miR-34a-5p and overexpression of miR-34a-5p alone disrupted cell-cycle progression through regulating its targets, recapitulating gene expression patterns observed in cardiac tissue of SMA mice. Our results identified a critical miRNA involved in SMA pathology, which sheds insights into the molecular basis of widespread tissue abnormalities observed in severe forms of SMA.

Induction of haemodynamic travelling waves by glial-related vasomotion in a rat model of neuroinflammation: implications for functional neuroimaging

BACKGROUND

Cerebral haemodynamics are crucial for brain homoeostasis and serve as a key proxy for brain activity. Although this process involves coordinated interaction between vessels, neurons, and glial cells, its dysregulation in neuroinflammation is not well understood.

METHODS

We used in vivo mesoscopic functional ultrasound imaging to monitor cerebral blood volume changes during neuroinflammation in male rats injected with lipopolysaccharide (LPS) in the visual cortex, under resting-state or visual stimulation, combined to advanced ex vivo techniques for glial cell reactivity analysis.

FINDINGS

Cortical neuroinflammation induced large oscillatory haemodynamic travelling waves in the frequency band of vasomotion (∼0.1 Hz) in both anaesthetized and awake rats. Vasomotor waves travelled through large distances between adjacent penetrating vessels, spanning the entire cortex thickness, and even extending to subcortical areas. Moreover, vasomotion amplitude correlated with microglial morphology changes and was significantly reduced by astrocytic toxins, suggesting that both microglia and astrocytes are involved in the enhancement of vasomotion during neuroinflammation. Notably, functional connectivity was increased under this oscillatory state and functional hyperaemia was exacerbated.

INTERPRETATION

These findings further reveal the spatiotemporal properties of cerebral vasomotion and suggest this is a major component of brain haemodynamics in pathological states. Moreover, reactive microglia and astrocytes are participating to increase vasomotion during neuroinflammation. For the field of functional neuroimaging, our results advocate for considering 0.1 Hz haemodynamic oscillations as an important complement to traditional measurements, particularly in neuroinflammatory conditions. Indeed, brain haemodynamics may provide insights not only into neuronal activity but also glial reactivity.

FUNDING

Supported by ANR ("LabCom-NI2D", "Labex Cortex") and Auvergne-Rhône-Alpes Region ("BI2D").

Astrocyte heterogeneity in ischemic stroke: Molecular mechanisms and therapeutic targets

Ischemic stroke is one of the major causes of death and disability in adults, bringing a significant economic burden to the society and families. Despite significant advancements in stroke treatment, focusing solely on neurons is insufficient for improving disease progression and prognosis. Astrocytes are the most ubiquitous cells in the brain, and they undergo morphological and functional changes after brain insults, which has been known as astrocyte reactivity. Transcriptomics have shown that reactive astrocytes (RA) are heterogeneous, and they can be roughly classified into neurotoxic and neuroprotective types, thereby affecting the development of central nervous system (CNS) diseases. However, the relationship between stroke and reactive astrocyte heterogeneity has not been fully elucidated, and regulating the heterogeneity of astrocytes to play a neuroprotective role may provide a new perspective for the treatment of stroke. Here we systematically review current advancements in astrocyte heterogeneity following ischemic stroke, elucidate the molecular mechanisms underlying their activation, and further summarize promising therapeutic agents and molecular targets capable of modulating astrocyte heterogeneity.

The effect of 50 Hz magnetic fields on cellular sensitivity of mouse spermatogenic cell lines to hydrogen peroxide

With the widespread application of electromagnetic technology, electromagnetic fields (EMFs) emitted from various electric and electronic devices have significantly altered the electromagnetic environment. This has raised concerns about the potential health impacts of EMFs. Previous studies have indicated that EMFs may influence male infertility, with oxidative stress proposed as a key factor; however, the underlying mechanisms remain unclear. In this study, we aimed to determine whether EMFs enhance the impact of oxidative stress on male infertility. We investigated the effects of 50 Hz magnetic fields (MFs) on the sensitivity of mouse spermatogenic cell lines (GC-1 spg and GC-2 spd) to low-dose hydrogen peroxide (H2O2, 5 and 10 μM). Our findings revealed that pre-exposure to 2.0 mT 50 Hz MFs for 24 h increased the sensitivity of GC-2 spd cells to low-dose H2O2 in terms of γH2AX foci formation, a marker for DNA damage repair. However, no significant changes were observed in DNA fragmentation, cell viability, or cell cycle progression in either GC-1 spg or GC-2 spd cells. In conclusion, our results suggest that 50 Hz MFs do not significantly enhance the sensitivity of mouse spermatogenic cell lines to low-dose H2O2.

Exploration of Pathogenesis and Cutting-Edge Treatment Strategies of Sarcopenia: A Narrative Review

Sarcopenia a progressive and multifactorial musculoskeletal syndrome characterized by loss of muscle mass and function, poses a significant global health challenge, particularly in aging populations. Epidemiological studies reveal that sarcopenia affects approximately 5-10% of the general population, with prevalence rates escalating dramatically after age 60 to reach 10-27% in older adults. This age-associated increase contributes significantly to healthcare burdens by elevating risks of disability, frailty, and mortality. Despite its profound impact, current clinical approaches to sarcopenia remain limited. While resistance exercise and protein supplementation form the cornerstone of management, their efficacy is often constrained by poor long-term adherence and variable individual responses, highlighting the urgent need for more comprehensive and personalized treatment strategies. The pathogenesis of sarcopenia is complex and influenced by various factors, including aging, inflammation, nutritional deficits, physical inactivity, and mitochondrial dysfunction. However, the precise molecular mechanisms underlying this condition are still not fully understood. Recent research has made significant strides in elucidating the intricate mechanisms contributing to sarcopenia, revealing novel insights into its molecular and cellular underpinnings. Notably, emerging evidence points to the pivotal role of mitochondrial dysfunction, altered myokine profiles, and neuromuscular junction degeneration in sarcopenia progression. Additionally, breakthroughs in stem cell therapy, exosome-based treatments, and precision nutrition offer promising avenues for clinical intervention. This review aims to synthesize the latest advancements in sarcopenia research, focusing on the novel contributions to its pathogenesis and treatment strategies. We explore emerging trends such as the role of cellular senescence, epigenetic regulation, and targeted therapeutic interventions that could reshape future approaches to managing sarcopenia. By highlighting recent breakthroughs and cutting-edge research, we hope to advance the understanding of sarcopenia and foster the translation of these findings into effective clinical therapies.

Phytochemical analysis and biological effects of Zingiber cassumunar extract and three phenylbutenoids: targeting NF-κB, Akt/MAPK, and caspase-3 pathways

BACKGROUND

Zingiber cassumunar Roxb., belonging to the Zingiberaceae family, is a medicinal herb commonly found in tropical regions, particularly in Southeast Asia. This research aims to investigate the preventive effects and anti-inflammatory properties of a phenylbutenoid extract (PE) obtained from the rhizomes of Z. cassumunar.

METHOD

The PE extract was prepared using green microwave extraction and subsequently analyzed by high-performance liquid chromatography. To evaluate its anti-inflammatory activity, lipopolysaccharide (LPS)-stimulated RAW264.7 cell models were used to measure the release of nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) using the Griess assay and enzyme-linked immunosorbent assay, respectively. Additionally, the inhibitory effects of PE on apoptosis and reactive oxygen species (ROS) production were evaluated in hydrogen peroxide-induced C2C12 myoblast cells. The expression of inflammation- and apoptosis-related proteins was evaluated using western blotting.

RESULTS

The results indicated that the PE was enriched with (E)-(3,4-dimethoxyphenyl)butadiene (DMPBD), (E)-1-(3,4-dimethoxyphenyl)but-3-en-1-ol (compound D), and (E)-1-(3,4-dimethoxyphenyl)but-3-en-1-yl acetate (compound D acetate). The PE contained a total phenylbutenoid content of 1.42% w/w. The PE exhibited potent anti-inflammatory properties, with half maximal inhibitory concentration (IC50) values of 7.2 µg/mL for NO, 23.4 µg/mL for TNF-α, and 19.8 µg/mL for IL-1β. In comparison, DMPBD exhibited lower activity against NO and TNF-α (IC50 values of 16.3 and 37.2 µg/mL, respectively) but similar efficacy against IL-1β (IC50 of 17.7 µg/mL) in LPS-induced RAW264.7 cells. All test compounds significantly decreased the percentage of apoptotic cells and suppressed intracellular ROS production in hydrogen peroxide-induced C2C12 myoblast cells. Notably, PE exhibited the highest potency in reducing apoptotic cells, with the lowest IC50 value of 11.6 µg/mL. PE inhibited the expression of p-p38/p38, pERK/ERK, and pAkt/Akt in the LPS-induced inflammatory response in RAW264.7 cells. Additionally, PE significantly suppressed the cleaved/pro-caspase-3 ratio without affecting Bax and Bcl-2 protein levels.

CONCLUSION

These findings suggest that PE and its phenylbutenoids exhibit anti-inflammatory effects through the inhibition of p38, ERK, and Akt signaling pathways, and anti-apoptotic effects via the inhibition of the caspase-3 pathway, highlighting their therapeutic potential for managing inflammatory and degenerative conditions.

CLINICAL TRIAL NUMBER

Not applicable.

Analysis of the mechanism of skeletal muscle atrophy from the pathway of decreased protein synthesis

Skeletal muscle atrophy is associated with denervation, cancer, diabetes, aging, immobilization, and inflammation, which can significantly impair mobility. It is primarily attributable to increased protein catabolism alongside reduced protein synthesis, although the precise mechanisms underlying this process are not yet fully known. Unlike in the pathway driving increased catabolism, fewer studies have explored the mechanism underpinning muscle atrophy under reduced protein synthesis. Therefore, this study aimed to focus on summarizing relevant studies on the reduction of protein synthesis leading to skeletal muscle atrophy, as driven by alterations in pathways such as the insulin-like growth factor-1-phosphatidylinositol 3-kinase-protein kinase B-rapamycin signaling pathway, glycogen synthase kinase-3, glucocorticoids, 5'-adenosine monophosphate-activated protein kinase, branched-chain amino acid sensors, myostatin, long-term proinflammatory factors, oxidative stress and mitochondrial dysfunction, calciumion concentration, activating transcription factor 4, and glycyl-tRNA synthetase alterations. Consolidating these data will provide a foundation and theoretical basis for further investigation into the mechanisms of muscle atrophy from the perspective of reduced protein synthesis pathways.

XLOC_015548 Mitigates Skeletal Muscle Atrophy via the Gadd45g/MEK/ERK Pathway and Redox Regulation

BACKGROUND

Skeletal muscle atrophy is a common musculoskeletal disorder that significantly reduces patient quality of life. Long non-coding RNA (lncRNA) XLOC_015548 has been identified as a pivotal regulator of C2C12 myoblast proliferation and differentiation. However, its role in mitigating denervation-induced muscle atrophy and the underlying mechanisms remain unclear.

METHODS

We employed lentiviral-mediated stable expression of XLOC_015548 in C2C12 myoblasts and skeletal muscle-specific XLOC_015548-edited mouse models to investigate the function of this lncRNA. Muscle atrophy models were established in vitro by glucocorticoid-induced atrophy with dexamethasone (DEX) and in vivo by sciatic nerve transection-induced denervation. The MEK inhibitor U0126 was used to assess the role of the growth arrest and DNA damage-inducible 45 gamma/mitogen-activated protein kinase kinase/extracellular signal-regulated kinase (Gadd45g/MEK/ERK) signaling pathway.

RESULTS

Overexpression of XLOC_015548 significantly activated the MEK/ERK signaling pathway (p < 0.05) by downregulating Gadd45g expression (p < 0.05) and promoting its cytoplasmic localization, thereby enhancing cell proliferation and myotube formation. Furthermore, XLOC_015548 reduced the level of reactive oxygen species (ROS) (p < 0.01), stabilized the mitochondrial membrane potential, and alleviated DEX-induced oxidative stress. These protective effects were partially reversed by U0126, confirming the involvement of the MEK/ERK pathway. Skeletal muscle-specific overexpression of XLOC_015548 in vivo significantly reduced denervation-induced muscle atrophy (q < 0.05) and increased the muscle fiber cross-sectional area.

CONCLUSION

XLOC_015548 plays a critical role in promoting myogenic differentiation and protecting against muscle atrophy by regulating Gadd45g expression, activating the MEK/ERK signaling pathway, and reducing oxidative stress. These findings underscore the therapeutic potential of XLOC_015548 in skeletal muscle atrophy, and provide a foundation for lncRNA-based treatment strategies.

Progranulin deficiency in the brain: the interplay between neuronal and non-neuronal cells

Heterozygous mutations in GRN gene lead to insufficient levels of the progranulin (PGRN) protein, resulting in frontotemporal dementia (FTD) with TAR DNA-binding protein 43 (TDP-43) inclusions, classified pathologically as frontotemporal lobar degeneration (FTLD-TDP). Homozygous GRN mutations are exceedingly rare and cause neuronal ceroid lipofuscinosis 11, a lysosomal storage disease with onset in young adulthood, or an FTD syndrome with late-onset manifestations. In this review, we highlight the broad spectrum of clinical phenotypes associated with PGRN deficiency, including primary progressive aphasia and behavioral variant of frontotemporal dementia. We explore these phenotypes alongside relevant rodent and in vitro human models, ranging from the induced pluripotent stem cell-derived neural progenitors, neurons, microglia, and astrocytes to genetically engineered heterotypic organoids containing both neurons and astrocytes. We summarize advantages and limitations of these models in recapitulating the main FTLD-GRN hallmarks, highlighting the role of non-cell-autonomous mechanisms in the formation of TDP-43 pathology, neuroinflammation, and neurodegeneration. Data obtained from patients' brain tissues and biofluids, in parallel with single-cell transcriptomics, demonstrate the complexity of interactions among the highly heterogeneous cellular clusters present in the brain, including neurons, astrocytes, microglia, oligodendroglia, endothelial cells, and pericytes. Emerging evidence has revealed that PGRN deficiency is associated with cell cluster-specific, often conserved, genetic and molecular phenotypes in the central nervous system. In this review, we focus on how these distinct cellular populations and their dysfunctional crosstalk contribute to neurodegeneration and neuroinflammation in FTD-GRN. Specifically, we characterize the phenotypes of lipid droplet-accumulating microglia and alterations of myelin lipid content resulting from lysosomal dysfunction caused by PGRN deficiency. Additionally, we consider how the deregulation of glia-neuron communication affects the exchange of organelles such as mitochondria, and the removal of excess toxic products such as protein aggregates, in PGRN-related neurodegeneration.

Current study on Pyrroloquinoline quinone (PQQ) therapeutic role in neurodegenerative diseases

Pyrroloquinoline quinone (PQQ) is a naturally occurring redox-active compound with potent antioxidant, mitochondrial-enhancing, and neuroprotective properties. Originally identified as a cofactor in bacterial enzymes, PQQ has garnered significant interest for its potential therapeutic role in neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD). It has reported that PQQ exerts its effects through several key molecular mechanisms, including the activation of antioxidant pathways via Nrf2/ARE signaling, enhancement of mitochondrial biogenesis and function through AMPK/PGC-1α, and the regulation of inflammatory processes through NF-κB inhibition. By improving cellular energy metabolism, reducing oxidative stress, and promoting neuronal survival, PQQ offers a multifaceted approach to counteracting the pathophysiological factors underlying neurodegeneration. Our review focusing on current study of PQQ on its enhancing neuroplasticity, and protecting neurons from damage induced by oxidative stress, mitochondrial dysfunction, and inflammation. Further we reviewed the significant signaling pathways that involved PQQ neuroprotective mechanisms, positioning it as a novel candidate for future therapeutic strategies targeting these debilitating conditions.

The Functions and Regulatory Mechanisms of Histone Modifications in Skeletal Muscle Development and Disease

Skeletal muscle development is a complex biological process regulated by many factors, such as transcription factors, signaling pathways, and epigenetic modifications. Histone modifications are important epigenetic regulatory factors involved in various biological processes, including skeletal muscle development, and play a crucial role in the pathogenesis of skeletal muscle diseases. Histone modification regulators affect the expression of many genes involved in skeletal muscle development and disease by adding or removing certain chemical modifications. In this review, we comprehensively summarize the functions and regulatory activities of the histone modification regulators involved in skeletal muscle development, regeneration, and disease.

Biomarkers of Skeletal Muscle Atrophy Based on Atrogenes Evaluation: A Systematic Review and Meta-Analysis Study

Muscle atrophy leads to decreased muscle mass, weakness, inactivity, and increased mortality. E3 ubiquitin ligases, key regulators of protein degradation via the ubiquitin-proteasome system, play a critical role in atrophic mechanisms. This meta-analysis followed Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, and its objective was to evaluate the association between E3 ligases Muscle Atrophy F-box (MAFbx)/Atrogin-1 (Fbxo32) and Muscle RING-finger protein 1 (MuRF-1) (TRIM63) E3 ligase mRNA levels, reductions in skeletal muscle CSA measures, and atrophy conditions. We examined papers published on PubMed®, Scopus, and Web of Science that studied E3 ligase gene expression signatures for Fbxo32 (MAFbx/Atrogin-1) and Trim63 (MuRF1) in different types of muscle atrophy and hypertrophy murine models. Twenty-nine studies selected by two independent raters were analyzed. Standardized mean differences (SMDs)/effect sizes (ESs) and 95% confidence intervals (CIs) were calculated for the outcomes using fixed-effects models. We found that 6- and 4.8-fold upregulation, respectively, of Fbxo32 and Trim63 was sufficient to reduce the ES to -3.89 (95% CI: -4.45 to -3.32) for the muscle fiber cross-sectional area and the development of skeletal muscle atrophy. I² and Q test statistics did not indicate heterogeneous data. There was a low probability of bias after both the funnel plot and Egger's test analyses. These results were sustained independently of the atrophic model and muscle type. Therefore, the magnitude of the increase in muscle Fbxo32 and Trim63 mRNA is a feasible, reliable molecular marker for skeletal muscle atrophy in mice. The next step for the Ubiquitin-proteasome system (UPS) field involves elucidating the targets of E3 ligases, paving the way for diagnostic and treatment applications in humans.

Dietary advanced glycation end-products exacerbate sarcopenia onset by activating apoptosis through PRMT1-mediated CRTC3 arginine methylation

BACKGROUND

Sarcopenia, the age-related decline in muscle mass and function, poses a major health risk to the elderly population. Although dietary advanced glycation end-products (AGEs) have been implicated in worsening sarcopenia, the precise molecular mechanisms remain unclear.

METHODS

A sarcopenia animal model was established by feeding a high AGE diet to C57BL/6 mice. Muscle function and mass were assessed using grip strength tests, and rotarod tests. Proteomic analysis was used to identify differentially expressed proteins. Immunoprecipitation, mass spectrometry, and co-immunoprecipitation were employed to investigate protein interactions both in vivo and in vitro. Quantitative reverse transcription PCR and Western blotting were conducted to measure gene and protein expression levels.

RESULTS

Our results revealed that dietary AGEs accelerated the onset of sarcopenia in mice by triggering apoptosis. Proteomic analysis showed a marked upregulation of protein arginine methyltransferase 1 (PRMT1) in the muscle tissues of mice fed a high AGE diet. PRMT1 mediated the arginine methylation of CREB-regulated transcription coactivator 3 (CRTC3) at the R534 site within its transactivation domain, leading to CRTC3 activation. The activated CRTC3, together with Forkhead box O3a (FOXO3a), transactivated the BAX (BCL2 associated X) gene, initiating Bax downstream signaling, promoting apoptosis in muscle cells, and contributing to muscle atrophy. Inhibition of PRMT1 prevented CRTC3 methylation and suppressed Bax-mediated apoptotic signaling in vitro. Moreover, in vivo treatment with PRMT1 and Bax inhibitors significantly attenuated AGE-induced sarcopenia in mice.

CONCLUSION

PRMT1-mediated CRTC3 arginine methylation plays a critical role in AGE-induced sarcopenia and suggests potential therapeutic targets for preventing sarcopenia progression.

Sex and age differences in glia and myelin in nonhuman primate and human spinal cords: implications for pathology

In a healthy central nervous system, glial cells are influenced by genetic, epigenetic, age, and sex factors. Aging typically causes astrocytes and microglia to undergo changes that reduce their neuroprotective functions and increase harmful activities. Additionally, sex-related differences in glial and myelin functions may impact neurological disorders. Despite this, few studies have investigated glial cells in primates, with most focusing on the brain. This study aims to explore whether glial cells and myelin exhibit age- and sex-related differences in the spinal cord of nonhuman primates and humans. We used immunohistochemistry and myelin staining to analyze healthy spinal cord samples from midlife and aged individuals of both sexes, focusing on Microcebus murinus (a small nonhuman primate) and humans. Primate spinal cords show distinct variations in glial markers and myelin characteristics related to sex and age, with differences varying between species. Notably, GFAP expression is sex-dependent in both primate species. We also observed greater differences in the expression of microglial markers than other glial markers. Overall, we found the opposite pattern for the g-ratio and oligodendrocytic marker between species. These findings suggest that glial cells may play a critical role in age- and sex-related differences in the prevalence and progression of spinal cord diseases.

Astragaloside IV Improves Muscle Atrophy by Modulating the Activity of UPS and ALP via Suppressing Oxidative Stress and Inflammation in Denervated Mice

Peripheral nerve injury is common clinically and can lead to neuronal degeneration and atrophy and fibrosis of the target muscle. The molecular mechanisms of muscle atrophy induced by denervation are complex and not fully understood. Inflammation and oxidative stress play an important triggering role in denervated muscle atrophy. Astragaloside IV (ASIV), a monomeric compound purified from astragalus membranaceus, has antioxidant and anti-inflammatory properties. The aim of this study was to investigate the effect of ASIV on denervated muscle atrophy and its molecular mechanism, so as to provide a new potential therapeutic target for the prevention and treatment of denervated muscle atrophy. In this study, an ICR mouse model of muscle atrophy was generated through sciatic nerve dissection. We found that ASIV significantly inhibited the reduction of tibialis anterior muscle mass and muscle fiber cross-sectional area in denervated mice, reducing ROS and oxidative stress-related protein levels. Furthermore, ASIV inhibits the increase in inflammation-associated proteins and infiltration of inflammatory cells, protecting the denervated microvessels in skeletal muscle. We also found that ASIV reduced the expression levels of MAFbx, MuRF1 and FoxO3a, while decreasing the expression levels of autophagy-related proteins, it inhibited the activation of ubiquitin-proteasome and autophagy-lysosome hydrolysis systems and the slow-to-fast myofiber shift. Our results show that ASIV inhibits oxidative stress and inflammatory responses in skeletal muscle due to denervation, inhibits mitophagy and proteolysis, improves microvascular circulation and reverses the transition of muscle fiber types; Therefore, the process of skeletal muscle atrophy caused by denervation can be effectively delayed.

High-intensity exercise alongside insulin alleviates muscle atrophy in type 1 diabetes mellitus concomitant with modulation of mitophagy-related proteins in skeletal muscle

BACKGROUND

Diabetes patients' quality of life can be severely impacted by diabetic muscle atrophy.

AIM

This study aimed to explore the impact of high-intensity exercise (HIE) alongside insulin treatment on muscle atrophy in a rat model of type 1 diabetes mellitus (T1DM).

METHODOLOGY

Fifty rats were allocated into five groups; Group 1, control sedentary (CS), T1DM was elicited in the rest of the groups by giving them Streptozotocin (STZ) (60 mg/kg), where group 2 (DS) remained sedentary, while groups 3,4,5 were treated with insulin after induction of diabetes. Group 4 (DI+MIE) and 5 (DI+ HIE) underwent moderate and high-intensity exercise, respectively.

RESULTS

HIE for 14 days combined with insulin treatment significantly restored muscle strength and mass with a significant modification in the mitophagy-related proteins and fibroblast growth factor 21 (FGF 21) compared to other treated groups.

CONCLUSION

This study concluded that there is a therapeutic role for HIE with insulin against T1DM-induced muscle atrophy.

Platelet-rich plasma enhances remodeling of combined gastrocnemius muscle and Achilles tendon injuries in rat model: Reducing fibrosis, modulating gene (MMP9, Bax, HMGB1, and IGF) expression, and restoring histopathological and ultrastructural changes

Muscle and tendon injuries are prevalent occurrences during sports activities. Platelet-rich plasma (PRP) is known for its rich content of factors essential for wound healing, inflammation reduction, and tissue repair. Despite its recognized benefits, limited information is available regarding PRP's effectiveness in addressing combined surgical injuries to the gastrocnemius muscle and Achilles tendon. The effects of PRP on muscle and tendon injury in rats were assessed through a set of biochemical markers, histopathological examinations, and immunohistochemistry analyses of muscular myogenin, desmin, and tendinous type I collagen. Additionally, mRNA expression levels of Matrix metalloproteinase-9 (MMP-9), Pro-apoptotic Bcl-2 Associated-X-protein (BAX), Insulin-like growth factor (IGF), and High mobility group box 1 protein (HMGB1) genes were evaluated. Induction of muscle and tendon injuries was associated with elevated levels of serum biomarkers such as C-reactive protein (CRP), Aspartate aminotransferase (AST), Lactate dehydrogenase A (LDH), and Creatine Kinase MB (CK-MB), delayed collagen fiber remodeling, and structural abnormalities in myofibrils. Furthermore, there was overexpression of MMP9, Bax, and HMGB1 genes, along with decreased expression of the IGF gene in this group. Treatment with PRP resulted in significant improvement of these reported findings, including enhanced collagen fiber remodeling, elevated levels of desmin and myogenin in muscle tissues, and increased expression of collagen type I in tendons. Additionally, PRP treatment led to reduced expression levels of MMP9, Bax, and HMGB1 genes, while the expression of the IGF gene increased. Overall, PRP treatment demonstrated substantial enhancement of the healing process in both muscle and tendon tissues in a surgical model of gastrocnemius skeletal muscle and Achilles tendon-induced injury. These findings suggest that PRP therapy may offer advantages in the treatment of physical-related injuries.

Serum/glucose starvation enhances binding of miR-4745-5p and miR-6798-5p to HNRNPA1 mRNA 3'UTR: A novel method to identify miRNAs binding to mRNA 3'UTR using λN peptide-boxB sequence

Serum/glucose starvation causes complete loss of heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) without altering mRNA levels. However, the mechanisms driving hnRNP A1 downregulation during serum/glucose starvation are not yet well understood. Using the novel interaction between the λN peptide and boxB sequence (λN/boxB system) and miRNA microarray analysis, we aimed to identify specific-binding microRNAs (miRs or miRNAs) targeting HNRNPA1 mRNA 3'UTR under serum/glucose-starved conditions. Four miRNAs were identified as serum/glucose starvation-driven miRNAs for HNRNPA1 mRNA 3'UTR. Reporter assays, anti-miRNA and mutated miRNA-based assays, photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation/reverse transcribed-quantitative polymerase chain reaction, and transient overexpression of miRNAs showed that miR-4745-5p and miR-6798-5p suppress hnRNP A1 protein levels via enhancement of binding to HNRNPA1 mRNA 3'UTR under serum/glucose-starved condition. miR-4745-5p and miR-6798-5p overexpression significantly decreased growth rates, which was rescued by co-transfection with anti-miRNA for miR-4745-5p and miR-6798-5p. Anti-miRNA transfection for miR-4745-5p and miR-6798-5p significantly increased growth rates under serum/glucose-starved conditions. Furthermore, hnRNP A1 overexpression recovered miR-4745-5p- and miR-6798-5p-induced growth suppression. These findings indicated that miR-4745-5p and miR-6798-5p are serum/glucose starvation-driven miRNAs for hnRNP A1 and validated the λN/boxB system as a simple and useful method for detecting mRNA 3'UTR-bound miRNA.

Endoplasmic reticulum stress and unfolded protein response: Roles in skeletal muscle atrophy

Skeletal muscle atrophy is commonly present in various pathological states, posing a huge burden on society and patients. Increased protein hydrolysis, decreased protein synthesis, inflammatory response, oxidative stress, mitochondrial dysfunction, endoplasmic reticulum stress (ERS) and unfolded protein response (UPR) are all important molecular mechanisms involved in the occurrence and development of skeletal muscle atrophy. The potential mechanisms of ERS and UPR in skeletal muscle atrophy are extremely complex and have not yet been fully elucidated. This article elucidates the molecular mechanisms of ERS and UPR, and discusses their effects on different types of muscle atrophy (muscle atrophy caused by disuse, cachexia, chronic kidney disease (CKD), diabetes mellitus (DM), amyotrophic lateral sclerosis (ALS), spinal muscular atrophy (SMA), spinal and bulbar muscular atrophy (SBMA), aging, sarcopenia, obesity, and starvation), and explores the preventive and therapeutic strategies targeting ERS and UPR in skeletal muscle atrophy, including inhibitor therapy and drug therapy. This review aims to emphasize the importance of endoplasmic reticulum (ER) in maintaining skeletal muscle homeostasis, which helps us further understand the molecular mechanisms of skeletal muscle atrophy and provides new ideas and insights for the development of effective therapeutic drugs and preventive measures for skeletal muscle atrophy.

Association between urinary volatile organic compound metabolites and sarcopenia in the US general population: a cross-sectional NHANES study from 2011 to 2018

Volatile organic compound (VOC) is a prevalent form of pollutant that has been linked to various human ailments, yet their connection to sarcopenia remains uncertain. This study seeks to examine the potential association between exposure to mixtures of metabolites of volatile organic compounds (mVOCs) and sarcopenia, while also investigating the potential mediating effects of oxidative stress and inflammation. Data from the 2011-2018 National Health and Nutrition Examination Survey (NHANES) were utilized for the analysis of the relationship between mVOCs and sarcopenia through logistic regression. The least absolute shrinkage and selection operator (LASSO) regression model was employed to identify key mVOCs, while the quantile-g computation model (qgcomp) and bayesian kernel machine regression (BKMR) models were utilized to examine the association between mVOC mixtures and sarcopenia. Potential mediating factors were explored through mediating analysis. Of the 2908 participants included in the study, 246 individuals (8.5%) were found to have sarcopenia. Logistic regression analysis revealed that five urinary VOC metabolites were positively correlated with an increased risk of sarcopenia. The key mVOCs identified through the LASSO method were further analyzed using qgcomp, which showed a 47% average increase in the risk of sarcopenia when exposed to a mixture of mVOCs (OR = 1.47, 95% CI 1.14-1.91). Four mVOCs components (DHBMA, 3HPMA, ATCA and 3,4MHA) have the largest weight. The BKMR results further confirm this joint association. Furthermore, Mediation analysis revealed that inflammation and oxidative stress mediate the relationship between exposure to mVOCs and sarcopenia. In conclusion, our study provides evidence suggesting that VOC exposure is linked to a heightened risk of sarcopenia, with inflammation and oxidative stress potentially serving as mediators in this relationship. It is recommended that additional cohort studies be conducted to validate these findings.

Mechanotransduction and Skeletal Muscle Atrophy: The Interplay Between Focal Adhesions and Oxidative Stress

Mechanical unloading leads to profound musculoskeletal degeneration, muscle wasting, and weakness. Understanding the specific signaling pathways involved is essential for uncovering effective interventions. This review provides new perspectives on mechanotransduction pathways, focusing on the critical roles of focal adhesions (FAs) and oxidative stress in skeletal muscle atrophy under mechanical unloading. As pivotal mechanosensors, FAs integrate mechanical and biochemical signals to sustain muscle structural integrity. When disrupted, these complexes impair force transmission, activating proteolytic pathways (e.g., ubiquitin-proteasome system) that accelerate atrophy. Oxidative stress, driven by mitochondrial dysfunction and NADPH oxidase-2 (NOX2) hyperactivation, exacerbates muscle degeneration through excessive reactive oxygen species (ROS) production, impaired repair mechanisms, and dysregulated redox signaling. The interplay between FA dysfunction and oxidative stress underscores the complexity of muscle atrophy pathogenesis: FA destabilization heightens oxidative damage, while ROS overproduction further disrupts FA integrity, creating a self-amplifying vicious cycle. Therapeutic strategies, such as NOX2 inhibitors, mitochondrial-targeted antioxidants, and FAK-activating compounds, promise to mitigate muscle atrophy by preserving mechanotransduction signaling and restoring redox balance. By elucidating these pathways, this review advances the understanding of muscle degeneration during unloading and identifies promising synergistic therapeutic targets, emphasizing the need for combinatorial approaches to disrupt the FA-ROS feedback loop.

Predictive model for sarcopenia in chronic kidney disease: a nomogram and machine learning approach using CHARLS data

Background

Sarcopenia frequently occurs as a complication among individuals with chronic kidney disease (CKD), contributing to poorer clinical outcomes. This research aimed to create and assess a predictive model for the risk of sarcopenia in CKD patients, utilizing data obtained from the China Health and Retirement Longitudinal Study (CHARLS).

Methods

Sarcopenia was diagnosed based on the Asian Working Group for Sarcopenia (AWGS 2019) criteria, including low muscle strength, reduced physical performance, and low muscle mass. The 2015 CHARLS data were split randomly into a training set (70%) and a testing set (30%). Forty-nine variables encompassing socio-demographic, behavioral, health status, and biochemical factors were analyzed. LASSO regression identified the most relevant predictors, and a logistic regression model was used to explore factors associated with sarcopenia. A nomogram was developed for risk prediction. Model accuracy was evaluated using calibration curves, while predictive performance was assessed through receiver operating characteristic (ROC) and decision curve analysis (DCA). Four machine learning algorithms were utilized, with the optimal model undergoing hyperparameter optimization to evaluate the significance of predictive factors.

Results

A total of 1,092 CKD patients were included, with 231 (21.2%) diagnosed with sarcopenia. Multivariate logistic regression revealed that age, waist circumference, LDL-C, HDL-C, triglycerides, and diastolic blood pressure are significant predictors. These factors were used to construct the nomogram. The predictive model achieved an AUC of 0.886 (95% CI: 0.858-0.912) in the training set and 0.859 (95% CI: 0.811-0.908) in the validation set. Calibration curves showed good agreement between predicted and actual outcomes. ROC and DCA analyses confirmed the model's strong predictive performance. The Gradient Boosting Machine (GBM) outperformed other machine learning models. Applying Bayesian optimization to the GBM achieved an AUC of 0.933 (95% CI: 0.913-0.953) on the training set and 0.932 (95% CI: 0.905-0.960) on the validation set. SHAP values identified age and waist circumference as the most influential factors.

Conclusion

The nomogram provides a reliable tool for predicting sarcopenia in CKD patients. The GBM model exhibits strong predictive accuracy, positioning it as a valuable tool for clinical risk assessment and management of sarcopenia in this population.

Combating chronic kidney disease-associated cachexia: A literature review of recent therapeutic approaches

In 2008, the Society on Sarcopenia, Cachexia, and Wasting Disorders introduced a generic definition for all types of cachexia: "a complex metabolic syndrome associated with the underlying illness characterized by a loss of muscle, with or without fat loss". It is well-known that the presence of inflammatory burden in end-stage renal disease (ESRD) patients may lead to the evolution of cachexia. Since the etiology of cachexia in chronic kidney disease (CKD) is multifactorial, thus the successful treatment must involve several concomitant measures (nutritional interventions, appetite stimulants, and anti-inflammatory pharmacologic agents) to provide integrated effective therapeutic modalities to combat causative factors and alleviate the outcomes of patients. Given the high mortality rate associated with cachexia, developing new therapeutic modalities are prerequisite for ameliorating patients with CKD worldwide. The present review aims to discuss some therapeutic strategies and provide an update on advances in nutritional approaches to counteract cachexia.

The Regulatory Role of CircAGGF1 in Myogenic Differentiation and Skeletal Muscle Development

Circular RNA (circRNA) has a significant impact on the maturation of skeletal muscle, although their precise functions within this framework remain largely uncharted. This study presents an investigation of the regulatory effect of circAGGF1 on myogenesis in myoblasts, including the potential molecular mechanisms involved. It is revealed that circAGGF1 facilitates the differentiation of myoblasts into other states while simultaneously enhancing the manifestation of type I muscle fibers. In vivo investigations with mice revealed the promotion of skeletal muscle expansion and maturation by circAGGF1, bolstering its regenerative capacity. Mechanistically, circAGGF1 interacts with miR-199a-3p by acting as a sponge, promoting the subsequent expression of Fgf7. Furthermore, rescue experiments indicated a counteraction of the myogenesis induced by circAGGF1 overexpression by miR-199a-3p. To summarize, this research highlights the role played by circAGGF1 in the development of skeletal muscle, providing a valuable resource for enhancing our understanding of skeletal muscle biology.

Stem cell therapy: A promising therapeutic approach for skeletal muscle atrophy

Skeletal muscle atrophy results from disruptions in the growth and metabolism of striated muscle, leading to a reduction or loss of muscle fibers. This condition not only significantly impacts patients’ quality of life but also imposes substantial socioeconomic burdens. The complex molecular mechanisms driving skeletal muscle atrophy contribute to the absence of effective treatment options. Recent advances in stem cell therapy have positioned it as a promising approach for addressing this condition. This article reviews the molecular mechanisms of muscle atrophy and outlines current therapeutic strategies, focusing on mesenchymal stem cells, induced pluripotent stem cells, and their derivatives. Additionally, the challenges these stem cells face in clinical applications are discussed. A deeper understanding of the regenerative potential of various stem cells could pave the way for breakthroughs in the prevention and treatment of muscle atrophy.

Liposome-Enabled Nanomaterials for Muscle Regeneration

Muscle regeneration is a vital biological process that is crucial for maintaining muscle function and integrity, particularly for the treatment of muscle diseases such as sarcopenia and muscular dystrophy. Generally, muscular tissues can self-repair and regenerate under various conditions, including acute or chronic injuries, aging, and genetic mutation. However, regeneration becomes challenging beyond a certain threshold, particularly in severe muscle injuries or progressive diseases. In recent years, liposome-based nanotechnologies have shown potential as promising therapeutic strategies for muscle regeneration. Liposomes offer an adaptable platform for targeted drug delivery due to their cell membrane-like structure and excellent biocompatibility. They can enhance drug solubility, stability, and targeted delivery while minimizing systemic side effects by different mechanisms. This review summarizes recent advancements, discusses current applications and mechanisms, and highlights challenges and future directions for possible clinical translation of liposome-based nanomaterials in the treatment of muscle diseases. It is hoped this review offers new insights into the development of liposome-enabled nanomedicine to address current limitations.

hBMSC-EVs alleviate weightlessness-induced skeletal muscle atrophy by suppressing oxidative stress and inflammation

BACKGROUND

Muscle disuse and offloading in microgravity are likely the primary factors mediating spaceflight-induced muscle atrophy, for which there is currently no effective treatment other than exercise. Extracellular vesicles derived from bone marrow mesenchymal stem cells (BMSC-EVs) possess anti-inflammatory and antioxidant properties, offering a potential strategy for combating weightless muscular atrophy.

METHODS

In this study, human BMSCs-EVs (hBMSC-EVs) were isolated using super-centrifugation and characterized. C2C12 myotube nutrition-deprivation and mice tail suspension models were established. Subsequently, the diameter of C2C12 myotubes, Soleus mass, cross-sectional area (CSA) of muscle fibers, and grip strength in mice were assessed to investigate the impact of hBMSC-EVs on muscle atrophy. Immunostaining, transmission electron microscopy observation, and western blot analysis were employed to assess the impact of hBMSC-EVs on muscle fiber types, ROS levels, inflammation, ubiquitin-proteasome system activity, and autophagy lysosome pathway activation in skeletal muscle atrophy.

RESULTS

The active hBMSC-EVs can be internalized by C2C12 myotubes and skeletal muscle. hBMSC-EVs can effectively reduce C2C12 myotube atrophy caused by nutritional deprivation, with a concentration of 10 × 108 particles/mL showing the best effect (P < 0.001). Additionally, hBMSC-EVs can down-regulate the protein levels associated with UPS and oxidative stress. Moreover, intravenous administration of hBMSC-EVs at a concentration of 1 × 1010 particles/mL can effectively reverse the reduction in soleus mass (P < 0.001), CSA (P < 0.01), and grip strength (P < 0.001) in mice caused by weightlessness. They demonstrate the ability to inhibit protein degradation mediated by UPS and autophagy lysosome pathway, along with the suppression of oxidative stress and inflammatory responses. Furthermore, hBMSC-EVs impede the transition of slow muscle fibers to fast muscle fibers via upregulation of Sirt1 and PGC-1α protein levels.

CONCLUSIONS

Our findings indicate that hBMSC-EVs are capable of inhibiting excessive activation of the UPS and autophagy lysosome pathway, suppressing oxidative stress and inflammatory response, reversing muscle fiber type transformation, effectively delaying hindlimb unloading-induced muscle atrophy and enhancing muscle function. Our study has further advanced the understanding of the molecular mechanism underlying muscle atrophy in weightlessness and has demonstrated the protective effect of hBMSC-EVs on muscle atrophy.

Single-cell RNA sequencing of neonatal cortical astrocytes reveals versatile cell clusters during astrocyte-neuron conversion

BACKGROUND

Astrocytes are extensively utilized as starting cells for neuronal conversion. Our previous study discovered that a portion of primary cultured mouse neonatal cortical astrocytes can be directly converted into neurons after exposure to a neurogenic induction condition. Recent in vivo studies have demonstrated astrocyte heterogeneity in terms of their developmental origin, molecular profile, physiology, and functional outputs. We hypothesized that the heterogeneity of primary astrocytes in our study could influence their conversion potential.

METHODS AND RESULTS

We performed single-cell RNA sequencing on cells harvested at key time points during in vitro astrocyte-to-neuron conversion, specifically on Day 1 and Day 9. Through single-cell RNA sequencing analysis, we identified several subpopulations of astrocytes, labeled as Astrocyte 1 to Astrocyte 3, based on distinct gene expression patterns. Pseudotime trajectory analysis predicted the existence of three distinct cell states throughout the conversion process. Astrocyte 3 exhibited a higher propensity for neuronal conversion, with proliferation genes like Mki67 being highly expressed. Additionally, several candidate genes were identified as potentially crucial in the conversion process. Astrocyte 3 is considered a unique subtype population of astrocytes.

CONCLUSIONS

Our investigation underscores the diversity of primary neonatal cortical astrocytes and provides critical insights into the potential for astrocyte-to-neuron conversion, which may be harnessed to enhance the efficiency of this astrocyte-neuron conversion process.

Single-Cell Landscape of the Cochlea Revealed Cell-Type-Specific Diversification in Hipposideros armiger Based on PacBio Long-Read Sequencing

Echolocation represents one of the most rapid adaptive sensorimotor modulation behaviors observed in mammals, establishing bats as one of the most evolutionarily successful mammals. Bats rely on high-frequency hearing for survival, but our understanding of its cellular molecular basis is scattered and segmented. Herein, we constructed the first single-cell transcriptomic landscape of the cochlea in Hipposideros armiger, a CF-FM bat, using a PacBio-optimized genome and compared it with the results obtained from unoptimized original genomes. Sixteen distinct cell types were distributed across five spatial regions of the cochlea. Notably, through hematoxylin and eosin staining and fluorescence in situ hybridization, we identified new types of spiral ganglion neuron (SGN) cells in the cochlea of H. armiger. These SGN cells are likely critical for auditory perception and may have driven the adaptive evolution of high-frequency hearing in this species. Furthermore, we uncovered the differentiation relationships of among specific cell types, such as the transition from supporting cells to hair cells. Using the cochlear cell atlas as a reference, cell types susceptible to deafness-associated genes (in the human) were also identified. In summary, this study provides novel insights into the cellular and molecular mechanisms underlying the adaptive high-frequency hearing in bats and highlights potential candidate cell types and genes for therapeutic interventions in hearing loss.

Microplastics/nanoplastics and neurological health: An overview of neurological defects and mechanisms

The widespread use of plastic products worldwide has brought about serious environmental issues. In natural environments, it's difficult for plastic products to degrade completely, and so they exist in the form of micro/nanoplastics (M/NPs), which have become a new type of pollutant. Prolonged exposure to M/NPs can lead to a series of health problems in humans, particularly toxicity to the nervous system, with consequences including neurodevelopmental abnormalities, neuronal death, neurological inflammation, and neurodegenerative diseases. Although direct evidence from humans is still limited, model organisms and organoids serve as powerful tools to provide important insights. This article summarizes the effects of M/NPs on the nervous system, focusing on cognitive function, neural development, and neuronal death. Mechanisms such as neurotransmitter synthesis and release, inflammatory responses, oxidative stress, the gut-brain axis, and the liver-brain axis are covered. The neurotoxicity induced by M/NPs may exacerbate or directly trigger neurodegenerative diseases and neurodevelopmental disorders. We particularly emphasize potential therapeutic agents that may counteract the neurotoxic effects induced by M/NPs, highlighting a novel future research direction. In summary, this paper cites evidence and provides mechanistic perspectives on the effects of M/NPs on neurological health, providing clues for eliminating M/NP hazards to human health in the future.

Analysis of Exon Skipping Applicability for Dysferlinopathies

Exon skipping, mediated through antisense oligonucleotides (ASOs), is a promising approach to exclude pathogenic variants from the DYSF gene and treat dysferlinopathies. Understanding the applicability of various exon skipping strategies in the total patient population, an analysis not previously performed, can help guide researchers in prioritizing therapies with the broadest potential impact. Using data from the UMD-DYSF database, we evaluated all reported pathogenic variants in dysferlinopathy patients for the applicability of single- or double-exon skipping approaches to exclude the pathogenic variants while maintaining the open reading frame. A total of 61 theoretically applicable exon skipping strategies were identified, with the potential to address 90.0% of the pathogenic variants reported-44.6% through single-exon skipping and 45.3% through double-exon skipping. The most broadly applicable targets include exons 28 and 29 (9.0%), exons 27 and 28 (6.7%), and exons 50 and 51 (5.4%). While numerous theoretically applicable strategies were identified, it remains unclear if the truncated proteins produced through each exon skipping strategy will have improved functionality to alleviate patient symptoms. Further preclinical studies and clinical trials will be essential to determine the effectiveness of these therapies, potentially expanding access to disease-modifying treatments for dysferlinopathy patients.

Association between the composite dietary antioxidant index and sarcopenia among United States adults: A cross-sectional study

BACKGROUND

Diets high in antioxidants are associated with decreased prevalence of sarcopenia. This study aimed to investigate whether the composite dietary antioxidant index (CDAI) and sarcopenia have an underlying relationship.

METHODS

We used the data from the National Health and Nutrition Examination Survey 2011-2018. According to dietary antioxidant intake, the CDAI was calculated for each individual. Appendicular skeletal muscle mass index was employed to determine sarcopenia. Multivariate weighted logistic models and restricted cubic spline regression analysis was undertaken to determine the association between CDAI and sarcopenia.

RESULTS

A total of 7012 participants were enrolled in this study, including 473 with sarcopenia (weighted percentage, 5.6%). Compared with the lowest tertile, those in the highest tertile of the CDAI exhibited a greater likelihood of being male, with lower body mass index, higher education level and economic standard, and more chance of being single or separated. In multivariate weighted logistic models, model 3 revealed a noteworthy inverse association between the CDAI and sarcopenia (odds ratio = 0.94; 95% CI, 0.91-0.98; P = 0.003). Compared with the lowest tertile, the highest tertile of CDAI was associated with a 0.57-fold risk of sarcopenia (95% CI, 0.42-0.77; P < 0.001). The inverse association between CDAI and sarcopenia strengthened in the participants with elevated education levels (P for interaction = 0.003).

CONCLUSION

The CDAI was inversely correlated with the prevalence of sarcopenia. As a comprehensive measurement representing antioxidant status, the CDAI may help manage and prevent sarcopenia.

Female reproductive disease, endometriosis: From inflammation to infertility

Despite the fact that endometriosis is a common gynecological disease that occurs in 10% of women of reproductive age, the pathogenesis and treatment strategy are not clear to date. Endometriosis patients are commonly characterized by adhesions in the pelvis or ovaries, which leads to prolonged inflammation in the abdominal cavity. To handle the chronic inflammation, changes of immune cells, including T cells, NK cells, and macrophage, are accompanied. Therefore, diverse cytokines and adhesions of the abdominal cavity lead to poor quality of ovarian follicles, inappropriate response to the hormone, and infertility. This review will guide researchers to summarize the molecular changes and identify new treatment strategies for endometriosis-mediated inflammation and pregnancy failure.

Association between brominated flame retardants and obesity: a mediation analysis through markers of oxidative stress and inflammation

BACKGROUND

Recent studies have provided compelling evidence that exposure to brominated flame retardants (BFRs) can adversely affect human health. We aim to explore the potential impact of BFRs on adiposity and central obesity.

METHODS

Data from the National Health and Nutrition Examination Surveys (NHANES) cycles conducted between 2009 and 2014 was used to study the connections between variables. After filtering, we analyzed a sample of 4,110 adults aged 20 years and above. Our goal was to examine the potential association between BFRs and consequences and investigate the part played by oxidative stress and inflammatory markers as intermediaries. To achieve this, we used advanced statistical methods such as weighted quantile sum (WQS) regression, quantile-based g-computation (QGC), and the Bayesian kernel machine regression (BKMR).

RESULTS

The findings showed that among the examined chemicals, exposure to PBDE85 (weight: 41%), PBDE100 (24%), and PBB153 (23%) may be the dominant contributors to general obesity risk. Upon controlling for all variables that could impact the results, it was found that the QGC outcomes indicated a positive correlation between exposure to mixtures of brominated flame retardants and the occurrence of abdominal obesity (OR = 1.187, 95% CI: 1.056-1.334, p = 0.004). Significant contributions were made by PBDE85 (52%), PBB153 (27%), and PBDE100 (21%). Mediation analysis shows that lymphatic cells (LC) and albumin (ALB) partially mediate the link between brominated flame retardants and obesity. The results of BKMR are generally consistent with those of WQS and QGC.

CONCLUSION

At a population level, our research has revealed a noteworthy correlation between BFRs and obesity. However, further investigation is required through prospective cohort studies and in-depth mechanistic exploratory studies.

The 'genetic zipper' method offers a cost-effective solution for aphid control

Twenty years ago, it was difficult to imagine the use of nucleic acids in plant protection as insecticides, but today it is a reality. New technologies often work inefficiently and are very expensive; however, qualitative changes occur during their development, making them more accessible and work effectively. Invented in 2008, contact oligonucleotide insecticides (olinscides, or DNA insecticides) based on the CUAD (contact unmodified antisense DNA) platform have been substantially improved and rethought. The main paradigm shift was demonstrating that unmodified antisense DNA can act as a contact insecticide. Key breakthroughs included identifying convenient target genes (rRNA genes), mechanism of action (DNA containment), and discovering insect pests (sternorrhynchans) with high susceptibility to olinscides. Today, the CUAD platform possesses impressive characteristics: low carbon footprint, high safety for non-target organisms, rapid biodegradability, and avoidance of target-site resistance. This next-generation class of insecticides creates opportunities for developing products tailored for specific insect pest populations. The 'genetic zipper' method, based on CUAD biotechnology, integrates molecular genetics, bioinformatics, and in vitro nucleic acid synthesis. It serves as a simple and flexible tool for DNA-programmable plant protection using unmodified antisense oligonucleotides targeting pest rRNAs. Aphids, key pests of important agricultural crops, can be effectively controlled by oligonucleotide insecticides at an affordable price, ensuring efficient control with minimal environmental risks. In this article, a low-dose concentration (0.1 ng/µL; 20 mg per hectare in 200 L of water) of the 11 nt long oligonucleotide insecticide Schip-11 shows effectiveness against the aphid Schizolachnus pineti, causing mortality rate of 76.06 ± 7.68 on the 12th day (p<0.05). At a consumption rate of 200 L per hectare, the cost of the required oligonucleotide insecticide is about 0.5 USD/ha using liquid-phase DNA synthesis making them competitive in the market and very affordable for lab investigations. We also show that non-canonical base pairing Golinscide: UrRNA is well tolerated in aphids. Thus, non-canonical base-pairing should be considered not to harm non-target organisms and can be easily solved during the design of oligonucleotide insecticides. The 'genetic zipper' method, based on CUAD biotechnology, helps quickly create a plethora of efficient oligonucleotide pesticides against aphids and other pests. Already today, according to our estimations, the 'genetic zipper' is potentially capable of effectively controlling 10-15% of all insect pests using a simple and flexible algorithm.

Sinapine suppresses ROS-induced C2C12 myoblast cell death through MAPK and autophagy pathways

Oxidative stress in skeletal muscle can lead to muscle atrophy through reactive oxygen species (ROS)-induced damage and cell death. tert-Butyl hydroperoxide (TBHP), an exogenous ROS generator, induces oxidative stress and cell death in various cells. Sinapine from cruciferous plants possesses beneficial effects, but its role in protecting skeletal muscle cells against ROS-induced cell death remains unclear. This study demonstrates that sinapine pretreatment significantly reduced TBHP-induced cell death and ROS accumulation in a dose-dependent manner. TBHP activated mitogen-activated protein kinase (MAPK) pathways including Akt, p38, and JNK, and triggered autophagy. Sinapine suppressed the phosphorylation of Akt, MEK3/6, p38, MEK4, and JNK, and modulated key autophagy markers. Notably, the co-treatment of MAPK inhibitors attenuated TBHP-induced cell death and LC3B-II accumulation. These findings suggest that sinapine is a promising phytochemical for mitigating oxidative stress-mediated muscle injury, offering potential therapeutic strategies for maintaining skeletal muscle homeostasis and addressing muscle-related pathologies.

Spinal muscular atrophy caused by compound heterozygous SMN1 mutations: two cases and literature review

Spinal muscular atrophy (SMA) is a rare neuromuscular disease, which is characterized by the degeneration of motor neurons, leading to symmetrical muscle weakness and atrophy. Description of two novel SMN1 mutations (patient1: c.683T > A, p.Leu228Ter; patient2: c.347 T > C, p.Ile116 Thr). We reported two patients with SMN1 mutations with the clinical features, and provided a literature review of the previously reported 22 cases. Two SMA patients showed progressive proximal lower limb weakness and milder clinical symptom. In a total of 22 cases, the most commonly observed SMN1 gene alteration was missense mutation (55%), followed by splicing defect (27%), nonsense (9%) and frameshift (9%). We discuss the possible decisive role of these intragenic mutations in the phenotypic results, which enriched the SMN 1 fine mutation database.

Ferroptosis and Its Potential Role in the Physiopathology of Skeletal Muscle Atrophy

Skeletal muscle atrophy is a major health concern, severely affecting the patient's mobility and life quality. In the pathological process of skeletal muscle atrophy, with the progressive decline in muscle quality, strength, and function, the incidence of falling, fracture, and death is greatly increased. Unfortunately, there are no effective treatments for this devastating disease. Thus, it is imperative to investigate the exact pathological molecular mechanisms underlying the development of skeletal muscle atrophy and to identify new therapeutic targets. Decreased muscle mass, strength, and muscle fiber cross-sectional area are typical pathological features and manifestations of skeletal muscle atrophy. Ferroptosis, an emerging type of programmed cell death, is characterized by iron-dependent oxidative damage, lipid peroxidation, and reactive oxygen species accumulation. Notably, the understanding of its role in skeletal muscle atrophy is emerging. Ferroptosis has been found to play an important role in the intricate interplay between the pathological mechanisms of skeletal muscle atrophy and its progression caused by multiple factors. This provides new opportunities and challenges in the treatment of skeletal muscle atrophy. Therefore, we systematically elucidated the ferroptosis mechanism and its progress in skeletal muscle atrophy, aiming to provide a comprehensive insight into the intricate relationship between ferroptosis and skeletal muscle atrophy from the perspectives of iron metabolism and lipid peroxidation and to provide new insights for targeting the pathways related to ferroptosis and the treatment of skeletal muscle atrophy.

Berberine Alleviates Uterine Inflammation in Rats via Modulating the TLR-2/p-PI3K/p-AKT Axis

Uterine inflammation affects 8% of women in the United States and 32% in developing nations, often caused by uncontrolled inflammation and oxidative stress. This condition significantly impacts women's health, productivity, and quality of life, and increases the risk of related morbidities leading to higher healthcare costs. Research now focuses on natural antioxidants and anti-inflammatory, particularly berberine (BBR), an isoquinoline alkaloid known for its antioxidant, anti-inflammatory, and antiapoptotic activities. The present study sought to examine the potential therapeutic efficacy of BBR against uterine inflammation induced by the intrauterine infusion of an iodine (I2) mixture in an experimental setting. Female Sprague Dawley rats (n = 6) were divided into five groups, control, sham, I2, I2 and BBR 10 mg/kg, and I2 and BBR 25 mg/kg-treated groups. Compared to I2 infusion, BBR treatment effectively restored normal uterine histopathology and reduced inflammatory markers such as interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), nuclear factor- kappa B (NF-κB), monocyte chemoattractant protein 1 (MCP1), and myeloperoxidase (MPO). It lowered oxidative markers like malondialdehyde (MDA), and increased antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). It balanced apoptotic genes by upregulating B-cell lymphoma 2 (Bcl-2) and downregulating Bcl-2-associated X protein (Bax). Furthermore, BBR reduced the expression of Toll-like receptor 2 (TLR-2), phosphorylated phosphatidylinositol 3‑kinase (p-PI3K), and phosphorylated protein kinase B (p-AKT) in the rats treated with intrauterine I2. Ultimately, the therapeutic benefits of BBR can be attributed, to some extent, to its antioxidant, anti-inflammatory, and antiapoptotic properties, in addition to its ability to modulate the TLR-2/p-PI3K/p-AKT axis.

New evidence of vascular defects in neurodegenerative diseases revealed by single cell RNA sequencing

Neurodegenerative diseases (NDs) involve the progressive loss of neuronal structure or function in the brain and spinal cord. Despite their diverse etiologies, NDs manifest similar pathologies. Emerging research identifies vascular defects as a previously neglected hallmark of NDs. The development and popularization of single-cell RNA sequencing (scRNA-seq) technologies have significantly advanced our understanding of brain vascular cell types and their molecular characteristics, including gene expression changes at the single-cell level in NDs. These unprecedented insights deepen our understanding of the pathogenic mechanisms underlying NDs. However, the occurrence and role of vascular defects in disease progression remain largely unexplored. In this paper, we systematically summarize recent advances in the structure and organization of the central nervous system vasculature in mice, healthy individuals, and patients with NDs, focussing primarily on disease-specific alterations in vascular cell types or subtypes. Combining scRNA-seq with pathology evidence, we propose that vascular defects, characterized by disruptions in cell types and structural integrity, may serve as common early features of NDs. Finally, we discuss several pathways through which vascular defects in NDs lead to neuronal degeneration. A deeper understanding of the causes and contributions of vascular defects to NDs aids in elucidating the pathogenic mechanisms and developing meaningful therapeutic interventions.

Bibliometric and visual analysis of single-cell multiomics in neurodegenerative disease arrest studies

Background

Neurodegenerative diseases are progressive disorders that severely diminish the quality of life of patients. However, research on neurodegenerative diseases needs to be refined and deepened. Single-cell polyomics is a technique for obtaining transcriptomic, proteomic, and other information from a single cell. In recent years, the heat of single-cell multiomics as an emerging research tool for brain science has gradually increased. Therefore, the aim of this study was to analyze the current status and trends of studies related to the application of single-cell multiomics in neurodegenerative diseases through bibliometrics.

Result

A total of 596 publications were included in the bibliometric analysis. Between 2015 and 2022, the number of publications increased annually, with the total number of citations increasing significantly, exhibiting the fastest rate of growth between 2019 and 2022. The country/region collaboration map shows that the United States has the most publications and cumulative citations, and that China and the United States have the most collaborations. The institutions that produced the greatest number of articles were Harvard Medical School, Skupin, Alexander, and Wiendl. Among the authors, Heinz had the highest output. Mathys, H accumulated the most citations and was the authoritative author in the field. The journal Nature Communications has published the most literature in this field. A keyword analysis reveals that neurodegenerative diseases and lesions (e.g., Alzheimer's disease, amyloid beta) are the core and foundation of the field. Conversely, single-cell multiomics related research (e.g., single-cell RNA sequencing, bioinformatics) and brain nerve cells (e.g., microglia, astrocytes, neural stem cells) are the hot frontiers of this specialty. Among the references, the article "Single-cell transcriptomic analysis of Alzheimer's disease" is the most frequently cited (1,146 citations), and the article "Cell types in the mouse cortex and hippocampus revealed by single-cell RNA-seq" was the most cited article in the field.

Conclusion

The objective of this study is to employ bibliometric methods to visualize studies related to single-cell multiomics in neurodegenerative diseases. This will enable us to summarize the current state of research and to reveal key trends and emerging hotspots in the field.

Da-yuan-yin decoction alleviates ulcerative colitis by inhibiting complement activation, LPS-TLR4/NF-κB signaling pathway and NET formation

ETHNOPHARMACOLOGICAL RELEVANCE

Da-yuan-yin decoction (DYY) is a classical traditional Chinese medicine prescription for ulcerative colitis (UC).

AIM OF STUDY

This study explored the protective effects and mechanisms of DYY on UC.

MATERIALS AND METHODS

The mice were fed 2.5% dextran sulfate sodium (DSS) for 7 days to establish UC. On the second day, DYY (0.4 g/kg, 0.8 g/kg, 1.6 g/kg) was orally administered daily for 7 consecutive days. The colon tissues and serum were measured by histopathological examination and biochemical analysis.

RESULTS

DYY significantly reduced the disease activity index (DAI) and severity of colon shortening and alleviated pathological changes in the colon tissue. DYY restored the protein expression of intestinal tight junction (TJ) protein (ZO-1, occludin and claudin-3). DYY remarkably decreased the level of lipopolysaccharide (LPS), Lactic acid (LA), circulating free DNA (cfDNA), complement (C3, C3a, C3c, C3aR1, C5a and C5aR1) and regulated the levels of inflammatory cytokines in serum. DYY significantly inhibited the expressions of nuclear factor kappa-B p65 (NF-κB p65) and Toll-like receptor 4 (TLR4), citrullinated histone H3 (CitH3) and myeloperoxidase (MPO), reactive oxygen species (ROS) peptidylarginine deiminase 4 (PAD4) and CD 11b, the mRNA levels of PADI4, MPO and ELANE in colon tissues.

CONCLUSIONS

DYY significantly attenuated DSS-induced UC, which was related with regulating the inflammatory response by the inhibition of complement activation, the LPS-TLR4/NF-κB signaling pathway and neutrophil extracellular traps (NETs) formation. DYY is a potential therapeutic agent for UC.

The role of ZEB1 in mediating the protective effects of metformin on skeletal muscle atrophy

Metformin is an important antidiabetic drug that has the potential to reduce skeletal muscle atrophy and promote the differentiation of muscle cells. However, the exact molecular mechanism underlying these functions remains unclear. Previous studies revealed that the transcription factor zinc finger E-box-binding homeobox 1 (ZEB1), which participates in tumor progression, inhibits muscle atrophy. Therefore, we hypothesized that the protective effect of metformin might be related to ZEB1. We investigated the positive effect of metformin on IL-1β-induced skeletal muscle atrophy by regulating ZEB1 in vitro and in vivo. Compared with the normal cell differentiation group, the metformin-treated group presented increased myotube diameters and reduced expression levels of atrophy-marker proteins. Moreover, muscle cell differentiation was hindered, when we artificially interfered with ZEB1 expression in mouse skeletal myoblast (C2C12) cells via ZEB1-specific small interfering RNA (si-ZEB1). In response to inflammatory stimulation, metformin treatment increased the expression levels of ZEB1 and three differentiation proteins, MHC, MyoD, and myogenin, whereas si-ZEB1 partially counteracted these effects. Moreover, marked atrophy was induced in a mouse model via the administration of lipopolysaccharide (LPS) to the skeletal muscles of the lower limbs. Over a 4-week period of intragastric administration, metformin treatment ameliorated muscle atrophy and increased the expression levels of ZEB1. Metformin treatment partially alleviated muscle atrophy and stimulated differentiation. Overall, our findings may provide a better understanding of the mechanism underlying the effects of metformin treatment on skeletal muscle atrophy and suggest the potential of metformin as a therapeutic drug.

Altered mRNA transport and local translation in iNeurons with RNA binding protein knockdown

Neurons rely on mRNA transport and local translation to facilitate rapid protein synthesis in processes far from the cell body. These processes allow precise spatial and temporal control of translation and are mediated by RNA binding proteins (RBPs), including those known to be associated with neurodegenerative diseases. Here, we use proteomics, transcriptomics, and microscopy to investigate the impact of RBP knockdown on mRNA transport and local translation in iPSC-derived neurons. We find thousands of transcripts enriched in neurites and that many of these transcripts are locally translated, possibly due to the shorter length of transcripts in neurites. Loss of frontotemporal dementia/amyotrophic lateral sclerosis (FTD/ALS)-associated RBPs TDP-43 and hnRNPA1 lead to distinct alterations in the neuritic proteome and transcriptome. TDP-43 knockdown (KD) leads to increased neuritic mRNA and translation. In contrast, hnRNPA1 leads to increased neuritic mRNA, but not translation, and more moderate effects on local mRNA profiles, possibly due to compensation by hnRNPA3. These results highlight the crucial role of FTD/ALS-associated RBPs in mRNA transport and local translation in neurons and the importance of these processes in neuron health and disease.

Inflammation and Fatty Infiltration Correlates with Rotator Cuff Muscle Atrophy in Hypercholesterolemic Yucatan Microswine

Rotator cuff injuries are the most common injuries among active and training astronauts. According to the CDC, 1 in 4 adults in the U.S. experience rotator cuff injuries, particularly affecting the supraspinatus muscle. Hypercholesterolemia, a condition characterized by high levels of LDL cholesterol, is prevalent in approximately 2 in 5 adults in the US and is a risk factor for worsened outcomes in shoulder inflammation and rotator cuff injury repairs. Chronic inflammation, a prolonged low-grade inflammatory state, can arise from conditions like hypercholesterolemia and contribute to muscle atrophy. Skeletal muscle atrophy can be caused by factors such as disuse, aging, malnutrition, and microgravity, and currently lacks approved drug therapies. Thus, gaining a comprehensive understanding of the associations between hypercholesterolemia, chronic inflammation, and skeletal muscle atrophy is imperative for developing effective strategies to manage this condition. We conducted an animal study in Yucatan miniswine to investigate the impact of a high-cholesterol diet on rotator cuff muscle. The results suggested the presence of chronic inflammation in rotator cuff muscle hypercholesterolemic swine, associated with elevated pro-inflammatory cytokines and intramuscular adipocytes, and skeletal muscle atrophy. The results also revealed upregulation of the FOXO3/TRIM63/Titin axis in a hyperlipidemic state. These findings open new perspectives for developing better treatment strategies by targeting the FOXO3/TRIM63/Titin axis to manage rotator cuff muscle atrophy in the context of hypercholesterolemia.