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1.
Aging Dis ; 2024 May 21.
Article in English | MEDLINE | ID: mdl-38916731

ABSTRACT

Reduced adipogenesis is a prominent characteristic of aging adipose tissue and is closely tied to the development of metabolic disorders associated with aging. Epigenetic modification plays a crucial role in the aging process, yet the role of N6-methyladenosine (m6A), the most prevalent RNA modification, in regulating adipose tissue aging remains uncertain. Our study found that levels of m6A and its recognition protein, heterogeneous nuclear ribonucleoprotein C (HNRNPC), decrease in adipose tissue as individuals age. Lower levels of HNRNPC were also linked to reduced adipogenesis during aging. Through loss and gain of function experiments with HNRNPC, we established a positive correlation between HNRNPC and adipogenesis in vitro. Hnrnpc-APKO mice displayed decreased adipogenesis, increased insulin resistance, elevated expression of aging-related and inflammation-related genes, decreased lipogenesis-related genes, and other metabolic disorders compared to their littermates. Additionally, we discovered that HNRNPC facilitated the stability of lymphocyte cytosolic protein 1 (Lcp1) mRNA by binding to the m6A motif of LCP1. Overexpression of LCP1 mitigated the inhibition of adipogenesis caused by decreased HNRNPC through modulation of cytoskeletal remodeling. Finally, our findings demonstrate that anti-aging treatments could enhance HNRNPC levels. In conclusion, HNRNPC is positively associated with reduced adipogenesis during aging, and increacing HNRNPC levels through anti-aging treatments highlights its potential as a therapeutic target for addressing metabolic imbalances in adipose tissue related to aging.

2.
Nat Immunol ; 25(6): 1020-1032, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38831106

ABSTRACT

The efficacy of T cell-based immunotherapies is limited by immunosuppressive pressures in the tumor microenvironment. Here we show a predominant role for the interaction between BTLA on effector T cells and HVEM (TNFRSF14) on immunosuppressive tumor microenvironment cells, namely regulatory T cells. High BTLA expression in chimeric antigen receptor (CAR) T cells correlated with poor clinical response to treatment. Therefore, we deleted BTLA in CAR T cells and show improved tumor control and persistence in models of lymphoma and solid malignancies. Mechanistically, BTLA inhibits CAR T cells via recruitment of tyrosine phosphatases SHP-1 and SHP-2, upon trans engagement with HVEM. BTLA knockout thus promotes CAR signaling and subsequently enhances effector function. Overall, these data indicate that the BTLA-HVEM axis is a crucial immune checkpoint in CAR T cell immunotherapy and warrants the use of strategies to overcome this barrier.


Subject(s)
Immunotherapy, Adoptive , Receptors, Chimeric Antigen , Receptors, Immunologic , Receptors, Tumor Necrosis Factor, Member 14 , Tumor Microenvironment , Animals , Humans , Immunotherapy, Adoptive/methods , Receptors, Tumor Necrosis Factor, Member 14/metabolism , Receptors, Tumor Necrosis Factor, Member 14/immunology , Receptors, Tumor Necrosis Factor, Member 14/genetics , Mice , Tumor Microenvironment/immunology , Receptors, Chimeric Antigen/immunology , Receptors, Chimeric Antigen/metabolism , Receptors, Chimeric Antigen/genetics , Receptors, Immunologic/metabolism , Receptors, Immunologic/genetics , T-Lymphocytes, Regulatory/immunology , Signal Transduction , Cell Line, Tumor , Neoplasms/immunology , Neoplasms/therapy , Mice, Knockout
3.
Geroscience ; 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38922380

ABSTRACT

Empagliflozin is currently known to decrease blood glucose levels, delay renal failure, and reduce the risk of cardiovascular death and all-cause mortality in patients with type 2 diabetes with cardiovascular disease. However, the effects of empagliflozin on the lifespan and health of naturally aged organisms are unclear. This study was designed to investigate the impacts and potential mechanisms of empagliflozin on lifespan and liver senescence in naturally aged mice. Our study revealed that empagliflozin improved survival and health in naturally aged mice. Empagliflozin extended the median survival of male mice by 5.9%. Meanwhile, empagliflozin improved learning memory and motor balance, decreased body weight, and downregulated the hepatic protein expression of P21, P16, α-SMA, and COL1A1. Empagliflozin modulates the structure of the intestinal flora, increasing the relative abundance of Lachnospiraceae, Ruminococcaceae, Lactobacillus, Blautia, and Muribaculaceae and decreasing the relative abundance of Erysipelotrichaceae, Turicibacter, and Dubosiella in naturally aged mice. Further exploration discovered that empagliflozin increased the concentration of SCFAs, decreased the levels of the inflammatory factors TNF-α, IL-6, and CXCL9, and regulated the PI3K/AKT/P21 and AMPK/SIRT1/NF-κB pathways, which may represent the underlying mechanisms involved in these beneficial hepatic effects. Taken together, the above results indicated that empagliflozin intervention could be considered a potential strategy for extending lifespan and slowing liver senescence in naturally aged mice.

4.
Article in English | MEDLINE | ID: mdl-38885107

ABSTRACT

Monocular Depth Estimation (MDE) plays a vital role in applications such as autonomous driving. However, various attacks target MDE models, with physical attacks posing significant threats to system security. Traditional adversarial training methods, which require ground-truth labels, are not directly applicable to MDE models that lack ground-truth depth. Some self-supervised model hardening techniques (e.g., contrastive learning) overlook the domain knowledge of MDE, resulting in suboptimal performance. In this work, we introduce a novel self-supervised adversarial training approach for MDE models, leveraging view synthesis without the need for ground-truth depth. We enhance adversarial robustness against real-world attacks by incorporating L0-norm-bounded perturbation during training. We evaluate our method against supervised learning-based and contrastive learning-based approaches specifically designed for MDE. Our experiments with two representative MDE networks demonstrate improved robustness against various adversarial attacks, with minimal impact on benign performance. Our code: https://github.com/Bob-cheng/DepthModelHardening.

5.
J Virol ; 98(6): e0003824, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38767356

ABSTRACT

Recent progress on chimeric antigen receptor (CAR)-NK cells has shown promising results in treating CD19-positive lymphoid tumors with minimal toxicities [including graft versus host disease (GvHD) and cytokine release syndrome (CRS) in clinical trials. Nevertheless, the use of CAR-NK cells in combating viral infections has not yet been fully explored. Previous studies have shown that CAR-NK cells expressing S309 single-chain fragment variable (scFv), hereinafter S309-CAR-NK cells, can bind to SARS-CoV-2 wildtype pseudotyped virus (PV) and effectively kill cells expressing wild-type spike protein in vitro. In this study, we further demonstrate that the S309-CAR-NK cells can bind to different SARS-CoV-2 variants, including the B.1.617.2 (Delta), B.1.621 (Mu), and B.1.1.529 (Omicron) variants in vitro. We also show that S309-CAR-NK cells reduce virus loads in the NOD/SCID gamma (NSG) mice expressing the human angiotensin-converting enzyme 2 (hACE2) receptor challenged with SARS-CoV-2 wild-type (strain USA/WA1/2020). Our study demonstrates the potential use of S309-CAR-NK cells for inhibiting infection by SARS-CoV-2 and for the potential treatment of COVID-19 patients unresponsive to otherwise currently available therapeutics. IMPORTANCE: Chimeric antigen receptor (CAR)-NK cells can be "off-the-shelf" products that treat various diseases, including cancer, infections, and autoimmune diseases. In this study, we engineered natural killer (NK) cells to express S309 single-chain fragment variable (scFv), to target the Spike protein of SARS-CoV-2, hereinafter S309-CAR-NK cells. Our study shows that S309-CAR-NK cells are effective against different SARS-CoV-2 variants, including the B.1.617.2 (Delta), B.1.621 (Mu), and B.1.1.529 (Omicron) variants. The S309-CAR-NK cells can (i) directly bind to SARS-CoV-2 pseudotyped virus (PV), (ii) competitively bind to SARS-CoV-2 PV with 293T cells expressing the human angiotensin-converting enzyme 2 (hACE2) receptor (293T-hACE2 cells), (iii) specifically target and lyse A549 cells expressing the spike protein, and (iv) significantly reduce the viral loads of SARS-CoV-2 wild-type (strain USA/WA1/2020) in the lungs of NOD/SCID gamma (NSG) mice expressing hACE2 (hACE2-NSG mice). Altogether, the current study demonstrates the potential use of S309-CAR-NK immunotherapy as an alternative treatment for COVID-19 patients.


Subject(s)
Angiotensin-Converting Enzyme 2 , COVID-19 , Killer Cells, Natural , Receptors, Chimeric Antigen , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Viral Load , Animals , SARS-CoV-2/immunology , Killer Cells, Natural/immunology , Angiotensin-Converting Enzyme 2/metabolism , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/immunology , Mice , Humans , Receptors, Chimeric Antigen/immunology , Receptors, Chimeric Antigen/genetics , Receptors, Chimeric Antigen/metabolism , COVID-19/immunology , COVID-19/virology , COVID-19/therapy , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Single-Chain Antibodies/immunology , Single-Chain Antibodies/genetics , Mice, SCID , Mice, Inbred NOD
6.
Nat Biomed Eng ; 8(5): 499-512, 2024 May.
Article in English | MEDLINE | ID: mdl-38693431

ABSTRACT

Bispecific T-cell engagers (BiTEs) bring together tumour cells and cytotoxic T cells by binding to specific cell-surface tumour antigens and T-cell receptors, and have been clinically successful for the treatment of B-cell malignancies. Here we show that a BiTE-sialidase fusion protein enhances the susceptibility of solid tumours to BiTE-mediated cytolysis of tumour cells via targeted desialylation-that is, the removal of terminal sialic acid residues on glycans-at the BiTE-induced T-cell-tumour-cell interface. In xenograft and syngeneic mouse models of leukaemia and of melanoma and breast cancer, and compared with the parental BiTE molecules, targeted desialylation via the BiTE-sialidase fusion proteins enhanced the formation of immunological synapses, T-cell activation and T-cell-mediated tumour-cell cytolysis in the presence of the target antigen. The targeted desialylation of tumour cells may enhance the potency of therapies relying on T-cell engagers.


Subject(s)
Neuraminidase , Animals , Neuraminidase/metabolism , Humans , Mice , Cell Line, Tumor , Recombinant Fusion Proteins/metabolism , Recombinant Fusion Proteins/genetics , T-Lymphocytes/immunology , Female , Antibodies, Bispecific/immunology , Antibodies, Bispecific/pharmacology , Lymphocyte Activation , N-Acetylneuraminic Acid/metabolism , N-Acetylneuraminic Acid/chemistry , Xenograft Model Antitumor Assays , T-Lymphocytes, Cytotoxic/immunology , Receptors, Antigen, T-Cell/metabolism , Receptors, Antigen, T-Cell/immunology
7.
Biomaterials ; 309: 122610, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38749307

ABSTRACT

Precise image-guided cancer immunotherapy holds immense potential in revolutionizing cancer treatment. The strategies facilitating activatable imaging and controlled therapeutics are highly desired yet to be developed. Herein, we report a new pyroptosis nanoinducer that integrates aggregation-induced emission luminogen (AIEgen) and DNA methyltransferase inhibitor with hypoxia-responsive covalent organic frameworks (COFs) for advanced image-guided cancer immunotherapy. We first synthesize and compare three donor-acceptor type AIEgens featuring varying numbers of electron-withdrawing units, and find that the incorporation of two acceptors yields the longest response wavelength and most effective photodynamic therapy (PDT) property, surpassing the performance of analogs with one or three acceptor groups. A COF-based nanoplatform containing AIEgen and pyroptosis drug is successfully constructed via the one-pot method. The intra-COF energy transfer significantly quenches AIEgen, in which both fluorescence and PDT properties greatly enhance upon hypoxia-triggered COF degradation. Moreover, the photodynamic process exacerbates hypoxia, accelerating pyroptosis drug release. The nanoagent enables sensitive delineation of tumor site through in situ activatable fluorescence signature. Thanks to the exceptional ROS production capabilities and hypoxia-accelerating drug release, the nanoagent not only inhibits primary tumor growth but also impedes the progression of distant tumors in 4T1 tumor-bearing mice through potent pyroptosis-mediated immune response. This research introduces a novel strategy for achieving activatable phototheranostics and self-accelerating drug release for synergetic cancer immunotherapy.


Subject(s)
Immunotherapy , Photochemotherapy , Pyroptosis , Pyroptosis/drug effects , Animals , Immunotherapy/methods , Mice , Photochemotherapy/methods , Humans , Cell Line, Tumor , Mice, Inbred BALB C , Female , Neoplasms/therapy , Neoplasms/drug therapy , Nanoparticles/chemistry , Metal-Organic Frameworks/chemistry
8.
Biochem Biophys Res Commun ; 716: 150002, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38697011

ABSTRACT

Type 2 diabetes mellitus (T2DM) significantly impairs the functionality and number of endothelial progenitor cells (EPCs) and resident endothelial cells, critical for vascular repair and regeneration, exacerbating the risk of vascular complications. GLP-1 receptor agonists, like dulaglutide, have emerged as promising therapeutic agents due to their multifaceted effects, including the enhancement of EPC activity and protection of endothelial cells. This study investigates dulaglutide's effects on peripheral blood levels of CD34+ and CD133+ cells in a mouse model of lower limb ischemia and its protective mechanisms against high-glucose-induced damage in endothelial cells. Results demonstrated that dulaglutide significantly improves blood flow, reduces tissue damage and inflammation in ischemic limbs, and enhances glycemic control. Furthermore, dulaglutide alleviated high-glucose-induced endothelial cell damage, evident from improved tube formation, reduced reactive oxygen species accumulation, and restored endothelial junction integrity. Mechanistically, dulaglutide mitigated mitochondrial fission in endothelial cells under high-glucose conditions, partly through maintaining SIRT1 expression, which is crucial for mitochondrial dynamics. This study reveals the potential of dulaglutide as a therapeutic option for vascular complications in T2DM patients, highlighting its role in improving endothelial function and mitochondrial integrity.


Subject(s)
Diabetes Mellitus, Experimental , Endothelial Progenitor Cells , Glucagon-Like Peptides , Glucose , Immunoglobulin Fc Fragments , Mitochondrial Dynamics , Recombinant Fusion Proteins , Sirtuin 1 , Animals , Immunoglobulin Fc Fragments/pharmacology , Glucagon-Like Peptides/analogs & derivatives , Glucagon-Like Peptides/pharmacology , Glucagon-Like Peptides/therapeutic use , Sirtuin 1/metabolism , Mitochondrial Dynamics/drug effects , Endothelial Progenitor Cells/drug effects , Endothelial Progenitor Cells/metabolism , Recombinant Fusion Proteins/pharmacology , Male , Mice , Glucose/metabolism , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/pathology , Mice, Inbred C57BL , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/pathology , Hypoglycemic Agents/pharmacology , Humans , Ischemia/metabolism , Ischemia/drug therapy , Ischemia/pathology
9.
Anal Methods ; 16(19): 3118-3124, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38699853

ABSTRACT

Small extracellular vesicles (sEVs) are a type of extracellular vesicle that carries many types of molecular information. The identification of sEVs is essential for the non-invasive detection and treatment of illnesses. Hence, there is a significant need for the development of simple, sensitive, and precise methods for sEV detection. Herein, a DNA tweezers-based assay utilizing a "turn-on" mechanism and proximity ligation was suggested for the efficient and rapid detection of sEVs through amplified fluorescence. The target facilitates the proximity combination of the C1 probe and C2 probe, resulting in the formation of a complete extended sequence. The elongated sequence can cyclically initiate the hairpin probe (HP), leading to the activation of DNA tweezers. An excellent linear correlation was achieved, with a limit of detection of 57 particles per µL. Furthermore, it has been effectively employed to analyze sEVs under intricate experimental conditions, demonstrating a promising and pragmatic prospect for future applications. Given that the identification of sEVs was successfully accomplished using a single-step method that exhibited exceptional sensitivity and strong resistance to interference, the proposed technique has the potential to provide a beneficial platform for accurate recognition of sEVs and early detection of diseases.


Subject(s)
Extracellular Vesicles , Nucleic Acid Hybridization , Extracellular Vesicles/chemistry , Humans , DNA/chemistry , Limit of Detection , Biosensing Techniques/methods
10.
Natl Sci Rev ; 11(6): nwae100, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38707203

ABSTRACT

Noise-induced hearing loss (NIHL) is a highly prevalent form of sensorineural hearing damage that has significant negative effects on individuals of all ages and there are no effective drugs approved by the US Food and Drug Administration. In this study, we unveil the potential of superparamagnetic iron oxide nanoparticle assembly (SPIOCA) to reshape the dysbiosis of gut microbiota for treating NIHL. This modulation inhibits intestinal inflammation and oxidative stress responses, protecting the integrity of the intestinal barrier. Consequently, it reduces the transportation of pathogens and inflammatory factors from the bloodstream to the cochlea. Additionally, gut microbiota-modulated SPIOCA-induced metabolic reprogramming in the gut-inner ear axis mainly depends on the regulation of the sphingolipid metabolic pathway, which further contributes to the restoration of hearing function. Our study confirms the role of the microbiota-gut-inner ear axis in NIHL and provides a novel alternative for the treatment of NIHL and other microbiota dysbiosis-related diseases.

11.
Heliyon ; 10(9): e30029, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38726186

ABSTRACT

Aims: This study aimed to examine the alterations in the serum CTRP7 and CTRP15 concentrations in patients newly diagnosed with type 2 diabetes mellitus (T2DM) and to assess the diagnostic potential of the log10 (CTRP7+CTRP15) for insulin resistance (IR) and T2DM. Methods: Serum CTRP7, CTRP15, and adiponectin levels were measured using an enzyme-linked immunosorbent assay (ELISA). Bioinformatics analysis was conducted to investigate CTRP7 and CTRP15-related genes and metabolic signaling pathways. Results: Log10 (CTRP7+CTRP15) levels were notably elevated in the impaired glucose tolerance (IGT) and T2DM cohorts compared with those in the normal control (NGT) cohort. Log10(CTRP7+CTRP15) exhibited positive correlations with HOMA-IR, area under the glucose curve (AUCg), HbA1c%, triglyceride (TG), visceral adiposity index (VAI), body mass index (BMI), and free fatty acid (FFA), levels but negative correlations with adiponectin. Multivariate stepwise regression analysis revealed that HOMA-IR, BMI, HbA1c and FFA levels were independent factors affecting the log10 (CTRP7+CTRP15). Logistic regression analysis revealed that log10 (CTRP7+CTRP15) was independently associated with T2DM and significantly associated with increased risk. Receiver operating characteristic (ROC) curve analysis indicated that the predictive value of log10 (CTRP7+CTRP15) for T2DM and IR was superior to that of CTRP7 or CTRP15 alone. Intervention studies demonstrated that insulin, FFAs and acute exercise contribute to the elevation of serum CTRP7 levels, while hyperglycemia inhibited CTRP7 secretion. Short-term changes in blood glucose, insulin, FFA and acute exercise had minimal effects on serum CTRP15 levels. Bioinformatics analysis revealed that CTRP7 and CTRP15 interact with multiple metabolism-related genes and are enriched in glucose and lipid metabolism-related pathways. Conclusion: Log10 (CTRP7+CTRP15) may serve as a valuable diagnostic marker for the management of metabolic-related diseases, particularly T2DM and IR.

13.
Int J Mol Sci ; 25(8)2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38673989

ABSTRACT

Mertk, a type I receptor tyrosine kinase and member of the TAM family of receptors, has important functions in promoting efferocytosis and resolving inflammation under physiological conditions. In recent years, Mertk has also been linked to pathophysiological roles in cancer, whereby, in several cancer types, including solid cancers and leukemia/lymphomas. Mertk contributes to oncogenic features of proliferation and cell survival as an oncogenic tyrosine kinase. In addition, Mertk expressed on macrophages, including tumor-associated macrophages, promotes immune evasion in cancer and is suggested to act akin to a myeloid checkpoint inhibitor that skews macrophages towards inhibitory phenotypes that suppress host T-cell anti-tumor immunity. In the present study, to better understand the post-translational regulation mechanisms controlling Mertk expression in monocytes/macrophages, we used a PMA-differentiated THP-1 cell model to interrogate the regulation of Mertk expression and developed a novel Mertk reporter cell line to study the intracellular trafficking of Mertk. We show that PMA treatment potently up-regulates Mertk as well as components of the ectodomain proteolytic processing platform ADAM17, whereas PMA differentially regulates the canonical Mertk ligands Gas6 and Pros1 (Gas6 is down-regulated and Pros1 is up-regulated). Under non-stimulated homeostatic conditions, Mertk in PMA-differentiated THP1 cells shows active constitutive proteolytic cleavage by the sequential activities of ADAM17 and the Presenilin/γ-secretase complex, indicating that Mertk is cleaved homeostatically by the combined sequential action of ADAM17 and γ-secretase, after which the cleaved intracellular fragment of Mertk is degraded in a proteasome-dependent mechanism. Using chimeric Flag-Mertk-EGFP-Myc reporter receptors, we confirm that inhibitors of γ-secretase and MG132, which inhibits the 26S proteasome, stabilize the intracellular fragment of Mertk without evidence of nuclear translocation. Finally, the treatment of cells with active γ-carboxylated Gas6, but not inactive Warfarin-treated non-γ-carboxylated Gas6, regulates a distinct proteolytic itinerary-involved receptor clearance and lysosomal proteolysis. Together, these results indicate that pleotropic and complex proteolytic activities regulate Mertk ectodomain cleavage as a homeostatic negative regulatory event to safeguard against the overactivation of Mertk.


Subject(s)
ADAM17 Protein , Amyloid Precursor Protein Secretases , Proteolysis , c-Mer Tyrosine Kinase , Humans , c-Mer Tyrosine Kinase/metabolism , c-Mer Tyrosine Kinase/genetics , ADAM17 Protein/metabolism , ADAM17 Protein/genetics , Amyloid Precursor Protein Secretases/metabolism , Amyloid Precursor Protein Secretases/genetics , Intercellular Signaling Peptides and Proteins/metabolism , THP-1 Cells , Macrophages/metabolism , Protein S/metabolism , Monocytes/metabolism , Tetradecanoylphorbol Acetate/pharmacology
14.
Nat Commun ; 15(1): 3377, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38643150

ABSTRACT

Zinc-alpha2-glycoprotein (AZGP1) has been implicated in peripheral metabolism; however, its role in regulating energy metabolism in the brain, particularly in POMC neurons, remains unknown. Here, we show that AZGP1 in POMC neurons plays a crucial role in controlling whole-body metabolism. POMC neuron-specific overexpression of Azgp1 under high-fat diet conditions reduces energy intake, raises energy expenditure, elevates peripheral tissue leptin and insulin sensitivity, alleviates liver steatosis, and promotes adipose tissue browning. Conversely, mice with inducible deletion of Azgp1 in POMC neurons exhibit the opposite metabolic phenotypes, showing increased susceptibility to diet-induced obesity. Notably, an increase in AZGP1 signaling in the hypothalamus elevates STAT3 phosphorylation and increases POMC neuron excitability. Mechanistically, AZGP1 enhances leptin-JAK2-STAT3 signaling by interacting with acylglycerol kinase (AGK) to block its ubiquitination degradation. Collectively, these results suggest that AZGP1 plays a crucial role in regulating energy homeostasis and glucose/lipid metabolism by acting on hypothalamic POMC neurons.


Subject(s)
Leptin , Pro-Opiomelanocortin , Mice , Animals , Leptin/metabolism , Phosphorylation , Pro-Opiomelanocortin/metabolism , Hypothalamus/metabolism , Homeostasis/physiology , Energy Metabolism/physiology , Neurons/metabolism
15.
Biogerontology ; 25(3): 567-581, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38403802

ABSTRACT

ABSTACT: With advancing age, the incidence of sarcopenia increases, eventually leading to a cascade of adverse events. However, there is currently a lack of effective pharmacological treatment for sarcopenia. Sodium-glucose co-transporter 2 inhibitor (SGLT2i) empagliflozin demonstrates anti-fibrotic capabilities in various organs. This study aims to determine whether empagliflozin can improve skeletal muscle fibrosis induced by sarcopenia in naturally aging mice. A natural aging model was established by feeding male mice from 13 months of age to 19 months of age. A fibrosis model was created by stimulating skeletal muscle fibroblasts with TGF-ß1. The Forelimb grip strength test assessed skeletal muscle function, and expression levels of COL1A1, COL3A1, and α-SMA were analyzed by western blot, qPCR, and immunohistochemistry. Additionally, levels of AMPKα/MMP9/TGFß1/Smad signaling pathways were examined. In naturally aging mice, skeletal muscle function declines, expression of muscle fibrosis markers increases, AMPKα expression is downregulated, and MMP9/TGFß1/Smad signaling pathways are upregulated. However, treatment with empagliflozin reverses this phenomenon. At the cellular level, empagliflozin exhibits similar anti-fibrotic effects, and these effects are attenuated by Compound C and siAMPKα. Empagliflozin exhibits anti-fibrotic effects, possibly associated with the AMPK/MMP9/TGFß1/Smad signaling pathways.


Subject(s)
AMP-Activated Protein Kinases , Aging , Benzhydryl Compounds , Fibrosis , Glucosides , Matrix Metalloproteinase 9 , Muscle, Skeletal , Signal Transduction , Smad Proteins , Sodium-Glucose Transporter 2 Inhibitors , Transforming Growth Factor beta1 , Animals , Male , Glucosides/pharmacology , Benzhydryl Compounds/pharmacology , Mice , Transforming Growth Factor beta1/metabolism , Sodium-Glucose Transporter 2 Inhibitors/pharmacology , Muscle, Skeletal/drug effects , Muscle, Skeletal/pathology , Muscle, Skeletal/metabolism , Aging/drug effects , Aging/metabolism , AMP-Activated Protein Kinases/metabolism , Signal Transduction/drug effects , Smad Proteins/metabolism , Matrix Metalloproteinase 9/metabolism , Sarcopenia/drug therapy , Sarcopenia/metabolism , Sarcopenia/prevention & control , Sarcopenia/pathology , Mice, Inbred C57BL
16.
Nat Sci Sleep ; 16: 155-175, 2024.
Article in English | MEDLINE | ID: mdl-38379755

ABSTRACT

Background: In recent years, multiple observational studies have confirmed the association between sleep traits and various human physiopathological states. However, the causal relationship between sleep traits and hypothalamic-pituitary-target gland axis (HPTGA) function remains unknown. Methods: We obtained summary statistics on sleep traits (insomnia, chronotype, and sleep duration (long and short)) from the UK Biobank database. Data related to the HPTGA functions were obtained from the publicly available database. Subsequently, a two-sample Mendelian randomization (MR) analysis was performed to investigate the causal relationship between different sleep traits and the HPTGA function. Reverse MR analysis was conducted to examine the direction of causality. Results: The MR analysis results suggested that chronotype is associated with decreased levels of six hormones in HPTGA. Sleep duration was causally associated with decreased levels of free thyroxine and progesterone. Both long and short sleep durations are detrimental to the secretion of prolactin-releasing peptide, somatostatin, and plasma cortisol, while short sleep duration can promote progesterone secretion. After gender stratification, we found that female reproductive function is more susceptible to the influence of unfavorable sleep traits. Conclusion: Our MR analysis indicated a significant causal association between chronotype and suppressed gonadal function in healthy adult humans, with no apparent gender-specific effect. Extreme sleep durations were also found to be detrimental to the maintenance of normal HPTGA secretion function. Compared to males, gonadal function in the female cohort is more susceptible to extreme sleep habits. Subsequent observational studies are urgently needed to confirm the underlying mechanisms.

17.
bioRxiv ; 2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38352578

ABSTRACT

Cell segmentation is a fundamental task in analyzing biomedical images. Many computational methods have been developed for cell segmentation, but their performances are not well understood in various scenarios. We systematically evaluated the performance of 18 segmentation methods to perform cell nuclei and whole cell segmentation using light microscopy and fluorescence staining images. We found that general-purpose methods incorporating the attention mechanism exhibit the best overall performance. We identified various factors influencing segmentation performances, including training data and cell morphology, and evaluated the generalizability of methods across image modalities. We also provide guidelines for choosing the optimal segmentation methods in various real application scenarios. We developed Seggal, an online resource for downloading segmentation models already pre-trained with various tissue and cell types, which substantially reduces the time and effort for training cell segmentation models.

18.
Stem Cell Res Ther ; 15(1): 38, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38336763

ABSTRACT

BACKGROUND: Nucleotide-binding oligomerization domain-containing protein 1 (NOD1) plays a pivotal role in inducing metabolic inflammation in diabetes. Additionally, the NOD1 ligand disrupts the equilibrium of bone marrow-derived hematopoietic stem/progenitor cells, a process that has immense significance in the development of diabetic retinopathy (DR). We hypothesized that NOD1 depletion impedes the advancement of DR by resolving bone marrow dysfunction. METHODS: We generated NOD1-/--Akita double-mutant mice and chimeric mice with hematopoietic-specific NOD1 depletion to study the role of NOD1 in the bone marrow-retina axis. RESULTS: Elevated circulating NOD1 activators were observed in Akita mice after 6 months of diabetes. NOD1 depletion partially restored diabetes-induced structural changes and retinal electrical responses in NOD1-/--Akita mice. Loss of NOD1 significantly ameliorated the progression of diabetic retinal vascular degeneration, as determined by acellular capillary quantification. The preventive effect of NOD1 depletion on DR is linked to bone marrow phenotype alterations, including a restored HSC pool and a shift in hematopoiesis toward myelopoiesis. We also generated chimeric mice with hematopoietic-specific NOD1 ablation, and the results further indicated that NOD1 had a protective effect against DR. Mechanistically, loss of hematopoietic NOD1 resulted in reduced bone marrow-derived macrophage infiltration and decreased CXCL1 and CXCL2 secretion within the retina, subsequently leading to diminished neutrophil chemoattraction and NETosis. CONCLUSIONS: The results of our study unveil, for the first time, the critical role of NOD1 as a trigger for a hematopoietic imbalance toward myelopoiesis and local retinal inflammation, culminating in DR progression. Targeting NOD1 in bone marrow may be a potential strategy for the prevention and treatment of DR.


Subject(s)
Diabetes Mellitus , Diabetic Retinopathy , Nod1 Signaling Adaptor Protein , Retinal Degeneration , Animals , Mice , Bone Marrow/metabolism , Diabetes Mellitus/metabolism , Diabetic Retinopathy/genetics , Diabetic Retinopathy/therapy , Hematopoietic Stem Cells/metabolism , Inflammation/genetics , Inflammation/metabolism , Mice, Inbred C57BL , Retina/metabolism , Nod1 Signaling Adaptor Protein/genetics , Nod1 Signaling Adaptor Protein/metabolism
19.
Luminescence ; 39(1): e4659, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38286609

ABSTRACT

Specific biomarker-activatable probes have revolutionized theranostics, being beneficial for precision medicine. Hypoxia is a critical pathological characteristic prevalent in numerous major diseases such as cancers, cardiovascular disorders, inflammatory diseases, and acute ischemia. Aggregation-induced emission luminogens (AIEgens) have emerged as a promising tool to tackle the biomedical issues. Of particular significance are the hypoxia-responsive AIEgens, representing a kind of crucial probe capable of delicately sensing and responding to the hypoxic microenvironment, thereby enhancing the precision of disease diagnosis and treatment. In this review, we summarize the recent advances of hypoxia-responsive AIEgens for varied biomedical applications. The hypoxia-responsive structures based on AIEgens, such as azobenzene, nitrobenzene, and N-oxide are presented, which are in response to the reduction property to bring about significant alternations in response spectra and/or fluorescence intensity. The bioapplications including imaging and therapy of tumor and ischemia diseases are discussed. Moreover, the review sheds light on the future challenges and prospects in this field. This review aims to provide comprehensive guidance and understanding into the development of activatable bioprobes, especially the hypoxia-responsive AIEgens for improving the diagnosis and therapy outcome of related diseases.


Subject(s)
Neoplasms , Precision Medicine , Humans , Theranostic Nanomedicine/methods , Optical Imaging/methods , Ischemia , Fluorescent Dyes/chemistry , Tumor Microenvironment
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