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1.
Biochem Biophys Res Commun ; 723: 150220, 2024 Jun 03.
Article En | MEDLINE | ID: mdl-38850811

Aging is characterized as the process of functional decline in an organism from adulthood, often marked by a progressive loss of cellular function and systemic deterioration of multiple tissues. Among the numerous molecular, cellular, and systemic hallmarks associated with aging, mitochondrial dysfunction is considered one of the pivotal factors that initiates the aging process. During aging, mitochondria undergo varying degrees of damage, resulting in impaired energy production and disruption of the homeostatic regulation of mitochondrial quality control systems, which in turn affects cellular energy metabolism and results in cellular dysfunction, accelerating the aging process. AMP-activated protein kinase (AMPK) and the mechanistic target of rapamycin complex 1 (mTORC1) are two central kinase complexes responsible for sensing intracellular nutrient levels, regulating metabolic homeostasis, modulating aging and play a crucial role in maintaining the homeostatic balance of mitochondria. Our previous studies found that the novel compound tetramethylpyrazine nitrone (TBN) can protect mitochondria via the AMPK/mTOR pathway in many animal models, extending healthy lifespan through the Nrf2 signaling pathway in nematodes. Building upon this foundation, we have posited a reasonable hypothesis, TBN can improve mitochondrial function to delay aging by regulating the AMPK/mTORC1 signaling pathway. This study focuses on the C. elegans, exploring the impact and underlying mechanisms of TBN on aging and mitochondrial function (especially the mitochondrial quality control system) during the aging process. The present studies demonstrated that TBN extends lifespan of wild-type nematodes and is associated with the AMPK/mTORC1 signaling pathway. TBN elevated ATP and NAD+ levels in aging nematodes while orchestrating mitochondrial biogenesis and mitophagy. Moreover, TBN was observed to significantly enhance normal activities during aging in C. elegans, such as mobility and pharyngeal pumping, concurrently impeding lipofuscin accumulation that were closely associated with AMPK and mTORC1. This study not only highlights the delayed effects of TBN on aging but also underscores its potential application in strategies aimed at improving mitochondrial function via the AMPK/mTOR pathway in C. elegans.

2.
Heliyon ; 10(9): e30169, 2024 May 15.
Article En | MEDLINE | ID: mdl-38699022

Nauclea officinalis, as a Chinese medicine in Hainan province, had the effect of treating lower limb ulcers, burn infections. In this paper, we studied the effect of Strictosamide (STR), the main bioactive compound in Nauclea officinals, on wound healing and explored its internal mechanism. Firstly, the wound healing potential of STR was evaluated in a rat model, demonstrating its ability to expedite wound healing, mitigate inflammatory infiltration, and enhance collagen deposition. Additionally, immunofluorescence analysis revealed that STR up-regulated the expression of CD31 and PCNA. Subsequently, target prediction, protein-protein interaction (PPI), gene ontology (GO), and pathway enrichment analyses were used to obtain potential targets, specific biological processes, and molecular mechanisms of STR for the potential treatment of wound healing. Furthermore, molecular docking was conducted to predict the binding affinity between STR and its associated targets. Additionally, in vivo and in vitro experiments confirmed that STR could increase the expression of P-PI3K, P-AKT and P-mTOR by activating the PI3K/AKT signaling pathway. In summary, this study provided a new explanation for the mechanism by which STR promotes wound healing through network pharmacology, suggesting that STR may be a new candidate for treating wound.

3.
Heart Rhythm ; 2024 May 28.
Article En | MEDLINE | ID: mdl-38815780

BACKGROUND: Atrial fibrillation (AF) is a common arrhythmia with high morbidity and mortality implications. Several studies have described a paradoxical inverse relationship between serum cholesterol and the risk of AF, but it remains unknown whether remnant cholesterol (RC) is associated with AF incidence. OBJECTIVE: This study aims to prospectively investigate the association between RC and AF. METHODS: A total of 392,783 participants free of AF at baseline from the UK Biobank were included for the analysis. Cox proportional hazards model, subgroup analysis, and sensitivity analyses were used to evaluate the independent association between RC levels and the risk of new-onset AF. Furthermore, we performed a discordance analysis by using the median cutoff points of low-density lipoprotein cholesterol (LDL-C) and RC. RESULTS: After a median follow-up of 12.8 years (interquartile range 12.0-13.6 years), a total of 23,558 participants experienced incident AF. Compared with the highest RC level, the lower RC level was associated with an increased risk of AF incidence (quartile 1 vs quartile 4: hazard ratio 1.396; 95% confidence interval [CI] 1.343-1.452). The results remained robust across a series of sensitivity analyses. In the discordance analyses, a significantly higher risk of AF was observed in participants with discordant low RC/high LDL-C levels than in those with concordant high RC/LDL-C levels. In the low LDL-C group, RC reduction even contributed to an additional 15.8% increased rate of incident AF (low RC/low LDL-C: hazard ratio 1.303; 95% CI 1.260-1.348 vs high RC/low LDL-C: hazard ratio 1.125; 95% CI 1.079-1.172). CONCLUSION: Low RC levels were associated with an increased risk of incident AF independent of traditional cardiovascular risk factors.

4.
Front Microbiol ; 15: 1397830, 2024.
Article En | MEDLINE | ID: mdl-38784808

The rise of antimicrobial resistance in ESKAPEE pathogens poses significant clinical challenges, especially in polymicrobial infections. Bacteriophage-derived endolysins offer promise in combating this crisis, but face practical hurdles. Our study focuses on engineering endolysins from a Klebsiella pneumoniae phage, fusing them with ApoE23 and COG133 peptides. We assessed the resulting chimeric proteins' bactericidal activity against ESKAPEE pathogens in vitro. ApoE23-Kp84B (CHU-1) reduced over 3 log units of CFU for A. baumannii, E. faecalis, K. pneumoniae within 1 h, while COG133-Kp84B (CHU-2) showed significant efficacy against S. aureus. COG133-L1-Kp84B, with a GS linker insertion in CHU-2, exhibited outstanding bactericidal activity against E. cloacae and P. aeruginosa. Scanning electron microscopy revealed alterations in bacterial morphology after treatment with engineered endolysins. Notably, CHU-1 demonstrated promising anti-biofilm and anti-persister cell activity against A. baumannii and E. faecalis but had limited efficacy in a bacteremia mouse model of their coinfection. Our findings advance the field of endolysin engineering, facilitating the customization of these proteins to target specific bacterial pathogens. This approach holds promise for the development of personalized therapies tailored to combat ESKAPEE infections effectively.

5.
J Transl Med ; 22(1): 488, 2024 May 21.
Article En | MEDLINE | ID: mdl-38773576

Ulcerative colitis (UC) is an idiopathic, chronic inflammatory condition of the colon, characterized by repeated attacks, a lack of effective treatment options, and significant physical and mental health complications for patients. The endoplasmic reticulum (ER) is a vital intracellular organelle in maintaining cellular homeostasis. Endoplasmic reticulum stress (ERS) is induced when the body is exposed to adverse external stimuli. Numerous studies have shown that ERS-induced apoptosis plays a vital role in the pathogenesis of UC. Mogroside V (MV), an active ingredient of Monk fruit, has demonstrated excellent anti-inflammatory and antioxidant effects. In this study, we investigated the therapeutic effects of MV on dextran sulfate sodium (DSS)-induced UC and its potential mechanisms based on ERS. The results showed that MV exerted a protective effect against DSS-induced UC in mice as reflected by reduced DAI scores, increased colon length, reduced histological scores of the colon, and levels of pro-inflammatory cytokines, as well as decreased intestinal permeability. In addition, the expression of ERS pathway including BIP, PERK, eIF2α, ATF4, CHOP, as well as the apoptosis-related protein including Caspase-12, Bcl-2 and Bax, was found to be elevated in UC. However, MV treatment significantly inhibited the UC and reversed the expression of inflammation signaling pathway including ERS and ERS-induced apoptosis. Additionally, the addition of tunicamycin (Tm), an ERS activator, significantly weakened the therapeutic effect of MV on UC in mice. These findings suggest that MV may be a therapeutic agent for the treatment of DSS-induced UC by inhibiting the activation of the ERS-apoptosis pathway, and may provide a novel avenue for the treatment of UC.


Apoptosis , Colitis, Ulcerative , Dextran Sulfate , Endoplasmic Reticulum Stress , Animals , Endoplasmic Reticulum Stress/drug effects , Colitis, Ulcerative/drug therapy , Colitis, Ulcerative/pathology , Colitis, Ulcerative/chemically induced , Colitis, Ulcerative/metabolism , Apoptosis/drug effects , Male , Mice, Inbred C57BL , Colon/pathology , Colon/drug effects , Triterpenes/pharmacology , Triterpenes/therapeutic use , Mice , Cytokines/metabolism , Permeability/drug effects , Signal Transduction/drug effects
6.
Environ Pollut ; 355: 124187, 2024 May 20.
Article En | MEDLINE | ID: mdl-38776996

Exploring the impact factors associated with biodiversity and the relationship between them has always been a concerned issue in recent years. However, the previous research mostly focus on theoretical layer. Accordingly, the relationship between landscape pattern and biodiversity is to be analyzed in this research. The landscape pattern determines the function and ecological process of the landscape, and affects the species flow, information flow and energy flow in the landscape. Land use patterns has inevitably left an impact on the landscape pattern. Landscape pattern determines the function and ecological process of landscape and thus plays a significant role in biodiversity. East Dongting Lake National Nature Reserve is taken as the research object of the paper, and the remote sensing image data of three different time periods are collected, including 2000, 2010 and 2020. With an interpretation of the vegetation landscape pattern changes inside the protected area to collect and analyze the vegetation coverage. By comparing landscape patterns and the dynamic changes of land use in different periods of time, the correlation between landscape pattern characteristics and regional biodiversity is to be analyzed. Research shows: (1) From 2000 to 2020, the vegetation coverage of East Dongting Lake increased, but the landscape shape, scale, diversity and uniformity index decreased to varying degrees. (2) At the class level of landscape type, the relationship between landscape index and biodiversity is different. A complex relationship between farmland landscape and biodiversity. There is a significant positive correlation between the index of grassland landscape type and the index of regional biodiversity. (3) The correlation analysis results at the landscape level show that the landscape characteristic index is positively correlated with the regional biodiversity index. The grassland landscape in the area is the main habitat of biological species. At the same time, as the main grain producing area, the impact of farmland landscape cannot be ignored. This study has certain theoretical guiding significance for the protection and management of biodiversity in the region in terms of maintaining landscape pattern in particular the grassland landscape area and increasing vegetation coverage in the process of land use.

7.
ACS Infect Dis ; 2024 May 09.
Article En | MEDLINE | ID: mdl-38725130

The design of siderophore-antibiotic conjugates is a promising strategy to overcome drug resistance in negative bacteria. However, accumulating studies have shown that only those antibiotics acting on the cell wall or cell membrane multiply their antibacterial effects when coupled with siderophores, while antibiotics acting on targets in the cytoplasm of bacteria do not show an obvious enhancement of their antibacterial effects when coupled with siderophores. To explore the causes of this phenomenon, we synthesized several conjugate probes using 3-hydroxypyridin-4(1H)-ones as siderophores and replacing the antibiotic cargo with 5-carboxyfluorescein (5-FAM) or malachite green (MG) cargo. By monitoring changes in the fluorescence intensity of FAM conjugate 20 in bacteria, the translocation of the conjugate across the outer membranes of Gram-negative pathogens was confirmed. Further, the use of the fluorogen activating protein(FAP)/MG system revealed that 3-hydroxypyridin-4(1H)-one-MG conjugate 26 was ultimately distributed mainly in the periplasm rather than being translocated into the cytosol of Escherichia coli and Pseudomonas aeruginosa PAO1. Additional mechanistic studies suggested that the uptake of the conjugate involved the siderophore-dependent iron transport pathway and the 3-hydroxypyridin-4(1H)-ones siderophore receptor-dependent mechanism. Meanwhile, we demonstrated that the conjugation of 3-hydroxypyridin-4(1H)-ones to the fluorescein 5-FAM can reduce the possibility of the conjugates crossing the membrane layers of mammalian Vero cells by passive diffusion, and the advantages of the mono-3-hydroxypyridin-4(1H)-ones as a delivery vehicle in the design of conjugates compared to the tri-3-hydroxypyridin-4(1H)-ones. Overall, this work reveals the localization rules of 3-hydroxypyridin-4(1H)-ones as siderophores to deliver the cargo into Gram-negative bacteria. It provides a theoretical basis for the subsequent design of siderophore-antibiotic conjugates, especially based on 3-hydroxypyridin-4(1H)-ones as siderophores.

8.
Arch Microbiol ; 206(6): 256, 2024 May 11.
Article En | MEDLINE | ID: mdl-38734826

A novel actinobacterium strain, designated HUAS 2-6 T, was isolated from the rhizosphere soil of Camellia oleifera Abel collected from Taoyuan County, Northwestern Hunan Province, South China. This strain was subjected to a polyphasic taxonomic study. Strain HUAS 2-6 T is characterized by morphology typical of members of the genus Streptomyces, with deep purplish vinaceous aerial mycelia and deep dull lavender substrate mycelia. Strain HUAS 2-6 T, based on the full-length 16S rRNA gene sequence analysis, exhibited the highest similarities to S. puniciscabiei S77T (99.31%), S. filipinensis NBRC 12860 T (99.10%), S. yaanensis CGMCC 4.7035 T (99.09%), S. fodineus TW1S1T (99.08%), S. broussonetiae CICC 24819 T (98.76%), S. achromogenes JCM 4121 T (98.69%), S. barringtoniae JA03T (98.69%), and less than 98.70% with other validly species. In phylogenomic tree, strain HUAS 2-6 T was clustered together with S. broussonetiae CICC 24819 T, suggesting that they were closely related to each other. However, average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH) between them were much less than the species cutoff values (ANI 96.7% and dDDH 70%). Moreover, in phenotypic and chemotaxonomic characteristics, strain HUAS 2-6 T is distinct from S. broussonetiae CICC 24819 T. On the basis of the polyphasic data, strain HUAS 2-6 T is proposed to represent a novel species, Streptomyces camelliae sp. nov. (= MCCC 1K04729T = JCM 35918 T).


Camellia , DNA, Bacterial , Phylogeny , RNA, Ribosomal, 16S , Rhizosphere , Soil Microbiology , Streptomyces , Streptomyces/isolation & purification , Streptomyces/genetics , Streptomyces/classification , Camellia/microbiology , RNA, Ribosomal, 16S/genetics , DNA, Bacterial/genetics , China , Fatty Acids/analysis , Bacterial Typing Techniques , Sequence Analysis, DNA , Base Composition
9.
bioRxiv ; 2024 May 15.
Article En | MEDLINE | ID: mdl-38798376

Replenishment of pancreatic beta cells is a key to the cure for diabetes. Beta cells regeneration is achieved predominantly by self-replication especially in rodents, but it was also shown that pancreatic duct cells can transdifferentiate into beta cells. How pancreatic duct cells undergo transdifferentiated and whether we could manipulate the transdifferentiation to replenish beta cell mass is not well understood. Using a genome-wide CRISPR screen, we discovered that loss-of-function of ALDH3B2 is sufficient to transdifferentiate human pancreatic duct cells into functional beta-like cells. The transdifferentiated cells have significant increase in beta cell marker genes expression, secrete insulin in response to glucose, and reduce blood glucose when transplanted into diabetic mice. Our study identifies a novel gene that could potentially be targeted in human pancreatic duct cells to replenish beta cell mass for diabetes therapy.

11.
World J Psychiatry ; 14(3): 409-420, 2024 Mar 19.
Article En | MEDLINE | ID: mdl-38617988

BACKGROUND: Dysphoria and despondency are prevalent psychological issues in patients undergoing Maintenance Hemodialysis (MHD) that significantly affect their quality of life (QOL). High levels of social support can significantly improve the physical and mental well-being of patients undergoing MHD. Currently, there is limited research on how social support mediates the relationship between dysphoria, despondency, and overall QOL in patients undergoing MHD. It is imperative to investigate this mediating effect to mitigate dysphoria and despondency in patients undergoing MHD, ultimately enhancing their overall QOL. AIM: To investigate the mediating role of social support in relationships between dysphoria, despondency, and QOL among patients undergoing MHD. METHODS: Participants comprised 289 patients undergoing MHD, who were selected using a random sampling approach. The Social Support Rating Scale, Self-Rating Anxiety Scale, Self-Rating Depression Scale, and QOL Scale were administered. Correlation analysis was performed to examine the associations between social support, dysphoria, despondency, and QOL in patients undergoing MHD. To assess the mediating impact of social support on dysphoria, despondency, and QOL in patients undergoing MHD, a bootstrap method was applied. RESULTS: Significant correlations among social support, dysphoria, despondency, and quality in patients undergoing MHD were observed (all P < 0.01). Dysphoria and despondency negatively correlated with social support and QOL (P < 0.01). Dysphoria and despondency had negative predictive impacts on the QOL of patients undergoing MHD (P < 0.05). The direct effect of dysphoria on QOL was statistically significant (P < 0.05). Social support mediated the relationship between dysphoria and QOL, and this mediating effect was significant (P < 0.05). Similarly, the direct effect of despondency on QOL was significant (P < 0.05). Moreover, social support played a mediating role between despondency and QOL, with a significant mediating effect (P < 0.05). CONCLUSION: These findings suggest that social support plays a significant mediating role in the relationship between dysphoria, despondency, and QOL in patients undergoing MHD.

12.
Chemosphere ; 356: 141841, 2024 May.
Article En | MEDLINE | ID: mdl-38582173

The coexistence of metal cations is often accompanied by organic pollution and could affect the environmental fate of organics by mediating the formation of cation bridges. However, the environmental fate and risk of organics in cation co-existing environments are poorly understood due to the lack of accurate identification of cation bridge formation and stability. In this study, the sorption of sulfamethoxazole (SMX) on montmorillonite (MT) with the coexistence of three different valence metal cations (Na+, Ca2+, and Cr3+) was investigated. Ca2+ and Cr3+ can significantly promote the sorption of SMX on MT for about 5∼10 times promotion, respectively, while Na+ bridges displayed little effect on the sorption of SMX. The sorption binding energy of SMX with MT-Ca (-44.01 kcal/mol) and MT-Cr (-64.57 kcal/mol) bridges was significantly lower than that with MT-Na (-38.45 kcal/mol) and MT (-39.39 kcal/mol), indicating that the sorption affinity of SMX on Cr and Ca bridges was much stronger. The higher valence of the cations also resulted in a more stable adsorbed SMX with less desorption fluctuation. In addition, the relatively higher initial concentration of SMX and the valence of cations increased the bonding density of the cation bridges, thus promoting the apparent sorption of SMX on MT to a certain extent. This work reveals the formation and function of cation bridges in the sorption of SMX on MT. It lays a theoretical foundation for further understanding the environmental fate and risk of organics.


Bentonite , Cations , Sulfamethoxazole , Bentonite/chemistry , Sulfamethoxazole/chemistry , Adsorption , Cations/chemistry
13.
Article En | MEDLINE | ID: mdl-38684027

Capillary force driven self-assembly micropillars (CFSA-MP) holds immense promise for the manipulation and capture of cells/tiny objects, which has great demands of wide size range and high robustness. Here, we propose a novel method to fabricate size-adjustable and highly robust CFSA-MP that can achieve wide size range and high stability to capture microspheres. First, we fabricate a microholes template with an adjustable aspect ratio using the spatial-temporal shaping femtosecond laser double-pulse Bessel beam-assisted chemical etching technique, and then the micropillars with adjustable aspect ratio are demolded by polydimethylsiloxane (PDMS). We fully demonstrated the advantages of the Bessel optical field by using the spatial-temporal shaping femtosecond laser double-pulse Bessel beams to broaden the height range of the micropillars, which in turn expands the size range of the captured microspheres, and finally achieving a wide range of capturing microspheres with a diameter of 5-410 µm. Based on the inverted mold technology, the PDMS micropillars have ultrahigh mechanical robustness, which greatly improves the durability. CFSA-MP has the ability to capture tiny objects with wide range and high stability, which indicates great potential applications in the fields of chemistry, biomedicine, and microfluidics.

14.
Eur J Med Chem ; 269: 116339, 2024 Apr 05.
Article En | MEDLINE | ID: mdl-38537513

The low permeability of the outer membrane of Gram-negative bacteria is a serious obstacle to the development of new antibiotics against them. Conjugation of antibiotic with siderophore based on the "Trojan horse strategy" is a promising strategy to overcome the outer membrane obstacle. In this study, series of antibacterial agents were designed and synthesized by conjugating the 3-hydroxypyridin-4(1H)-one based siderophores with cajaninstilbene acid (CSA) derivative 4 which shows good activity against Gram-positive bacteria by targeting their cell membranes but is ineffective against Gram-negative bacteria. Compared to the inactive parent compound 4, the conjugates 45c or 45d exhibits significant improvement in activity against Gram-negative bacteria, including Escherichia coli, Klebsiella pneumoniae and especially P. aeruginosa (minimum inhibitory concentrations, MICs = 7.8-31.25 µM). The antibacterial activity of the conjugates is attributed to the CSA derivative moiety, and the action mechanism is by disruption of bacterial cell membranes. Further studies on the uptake mechanisms showed that the bacterial siderophore-dependent iron transport system was involved in the uptake of the conjugates. In addition, the conjugates 45c and 45d showed a lower cytotoxic effects in vivo and in vitro and a positive therapeutic effect in the treatment of C. elegans infected by P. aeruginosa. Overall, our work describes a new class and a promising 3-hydroxypyridin-4(1H)-one-CSA derivative conjugates for further development as antibacterial agents against Gram-negative bacteria.


Anti-Bacterial Agents , Salicylates , Siderophores , Stilbenes , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Siderophores/pharmacology , Siderophores/metabolism , Caenorhabditis elegans/metabolism , Gram-Negative Bacteria , Bacteria/metabolism , Microbial Sensitivity Tests
15.
Nat Biomed Eng ; 2024 Mar 15.
Article En | MEDLINE | ID: mdl-38491329

Dental calculi can cause gingival bleeding and periodontitis, yet the mechanism underlying the formation of such mineral build-ups, and in particular the role of the local microenvironment, are unclear. Here we show that the formation of dental calculi involves bacteria in local mature biofilms converting the DNA in neutrophil extracellular traps (NETs) from being degradable by the enzyme DNase I to being degradation resistant, promoting the nucleation and growth of apatite. DNase I inhibited NET-induced mineralization in vitro and ex vivo, yet plasma DNases were ineffective at inhibiting ectopic mineralization in the oral cavity in rodents. The topical application of the DNA-intercalating agent chloroquine in rodents fed with a dental calculogenic diet reverted NET DNA to its degradable form, inhibiting the formation of calculi. Our findings may motivate therapeutic strategies for the reduction of the prevalence of the deposition of bacteria-driven calculi in the oral cavity.

16.
Pest Manag Sci ; 2024 Mar 20.
Article En | MEDLINE | ID: mdl-38507262

BACKGROUND: Insects mainly rely on innate immunity against pathogen infection. Plagiodera versicolora (Coleoptera: Chrysomelidae), is a worldwide leaf-eating forest pest in salicaceous trees. However, the mechanisms behind the immunodeficiency pathway (IMD) remain poorly understood. RESULTS: In this study, we obtained a Relish gene from transcriptome analysis. Tissue and instar expression profiles were subsequently obtained using quantitative real-time polymerase chain reaction analysis. The results showed that Relish has high expression levels in eggs, larvae and adults, and especially in fat bodies. Transcripts of the tested antimicrobial peptides (AMPs), defensin1, defensin2 and attacin2 were downregulated by dsRelish. Knockdown of Relish led to greater mortality in larvae after Staphylococcus aureus infection. In addition, we performed bacterial 16S ribosomal RNA-based high-throughput sequencing. The results showed that the relative abundance of some gut bacteria was significantly altered after dsRelish ingestion. CONCLUSION: This study provides a greater understanding of the IMD signaling pathway, facilitating functional studies of Relish in P. versicolora. Moreover, a genetic pest management technique might be developed using Relish as a lethal gene to control the pest P. versicolora. © 2024 Society of Chemical Industry.

17.
iScience ; 27(4): 109358, 2024 Apr 19.
Article En | MEDLINE | ID: mdl-38544565

Mesenchymal stem cell (MSC)-mediated coupling of osteogenesis and angiogenesis is a critical phenomenon in bone formation. Herein, we investigated the role and mechanism of SGMS1 in the osteogenic differentiation of MSCs and, in combination with osteogenesis and angiogenesis, to discover new therapeutic targets for skeletal dysplasia and bone defects. SGMS1 addition accelerated MSC osteogenic differentiation, whereas SGMS1 silencing suppressed this process. Moreover, SGMS1 overexpression inhibited ceramide (Cer) and promoted sphingomyelin (SM) levels. SM treatment neutralized the suppressive effect of shSGMS1 on osteogenesis. SGMS1 restrained PP2A activity by regulating Cer/SM metabolism and thus enhanced the levels of phosphorylated Akt, Runx2, and vascular endothelial growth factor (VEGF). Furthermore, SGMS1 transcription was regulated by Runx2. SGMS1 increased MSC-mediated angiogenesis by promoting VEGF expression. SGMS1 addition promoted rat bone regeneration in vivo. In conclusion, SGMS1 induces osteogenic differentiation of MSCs and osteogenic-angiogenic coupling through the regulation of the Cer/PP2A/Akt signaling pathway.

18.
Quant Imaging Med Surg ; 14(3): 2357-2369, 2024 Mar 15.
Article En | MEDLINE | ID: mdl-38545064

Background: Distinguishing light-chain cardiac amyloidosis (AL CA) from left ventricular wall thickening (LVWT) resulted from other etiologies has proven to be challenging. This study aimed to determine the sensitivity and specificity of relative apical sparing in diagnosing AL CA and investigate the differences in clinical and echocardiographic characteristics between AL CA patients with apical sparing and those with non-apical sparing. Methods: A total of 63 consecutive patients with AL CA, 102 consecutive patients with LVWT (including 51 hypertrophic cardiomyopathy (HCM) and 51 hypertension) and 33 healthy individuals were recruited retrospectively at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology. Conventional and speckle tracking echocardiography were performed on all subjects. Results: Although wall thickening was observed in all patients, almost all functional parameters were worse in AL CA, except for relative apical longitudinal strain (LS) (P=0.906). Of 63 patients with AL CA, only 17.5% (n=11) showed an apical sparing pattern. Patients with apical sparing had poorer cardiac performance than those with non-apical sparing. Relative apical sparing showed the lowest diagnostic accuracy with an area under the curve (AUC) of 0.58 [95% confidence interval (CI): 0.49-0.67, sensitivity: 17.5%, specificity: 98.0%, P=0.095] to detect AL CA, but right ventricular strain (RVS) (AUC: 0.86, P<0.001) showed the highest among all echocardiographic parameters. When diagnosing AL CA patients with non-apical sparing, RVS continued to maintain excellent diagnostic accuracy (AUC: 0.84, P<0.001), followed by left atrial reservoir strain (LASr) (AUC: 0.77, P<0.001). Conclusions: The diagnostic value of relative apical sparing for AL CA was limited with low sensitivity. In clinical practice, the diagnosis of early AL CA patients should not solely rely on relative apical sparing.

19.
bioRxiv ; 2024 Mar 04.
Article En | MEDLINE | ID: mdl-38496417

Type 1 diabetes (T1D) arises from autoimmune-mediated destruction of insulin-producing pancreatic beta cells. Recent advancements in the technology of generating pancreatic beta cells from human pluripotent stem cells (SC-beta cells) have facilitated the exploration of cell replacement therapies for treating T1D. However, the persistent threat of autoimmunity poses a significant challenge to the survival of transplanted SC-beta cells. Genetic engineering is a promising approach to enhance immune resistance of beta cells as we previously showed by inactivating of the Renalase (Rnls) gene. Here we demonstrate that Rnls loss-of-function in beta cells shape autoimmunity by mediating a regulatory Natural Killer (NK) cell phenotype important for the induction of tolerogenic antigen presenting cells. Rnls-deficient beta cells mediate cell-cell-contact-independent induction of hallmark anti-inflammatory cytokine Tgfß1 in NK cells. In addition, surface expression of key regulatory NK immune checkpoints CD47 and Ceacam1 are markedly elevated on beta cells deficient for Rnls. Enhanced glucose metabolism in Rnls mutant beta cells is responsible for upregulation of CD47 surface expression. These findings are crucial to a better understand how genetically engineered beta cells shape autoimmunity giving valuable insights for future therapeutic advancements to treat and cure T1D.

20.
Int J Biol Macromol ; 265(Pt 2): 130928, 2024 Apr.
Article En | MEDLINE | ID: mdl-38513901

In this study, black highland barley semi-dried noodles (BHBSNs) were adjusted to acidic pH (5.0, 4.5, 4.0) with an acidity regulator (monosodium fumarate) for obtaining low glycemic index (GI) BHBSNs, and the changes in the in vitro starch digestion, free phenolic content, and α-amylase activity in BHBSNs were investigated. The estimated glycemic index (eGI) of BHBSNs decreased from 59.23 to 52.59, 53.89 and 53.61, respectively, as the pH was adjusted from 6.0 to 5.0, 4.5, 4.0. As the pH of BHBSNs decreased, the equilibrium hydrolysis (C∞) decreased, and kinetic coefficient (k) decreased and then increased. Compared to the control, the pH of the digestive fluid decreased during digestion with decreasing pH, and the α-amylase inhibition of BHBSNs with pH 5.0, 4.5, and 4.0 increased by 56.54 %, 75.18 %, and 107.98 %, respectively. In addition, as the pH of BHBSNs decreased, the free phenolic content and the content of released phenolics during digestion increased. Pearson correlations analysis showed that the increase in α-amylase inhibition and phenolic release during digestion induced by acidic pH was negatively correlated with the eGI and C∞ of BHBSNs. This study indicated that acidic pH condition could modulate starch digestion for preparing low GI BHBSNs.


Hordeum , Starch , Starch/chemistry , alpha-Amylases , Phenols/pharmacology , Digestion , Hydrogen-Ion Concentration
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