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1.
Artículo en Inglés | MEDLINE | ID: mdl-38748238

RESUMEN

OBJECTIVE: To investigate the mediating role of depressive symptoms in the relationship between negative life events (NLEs) and suicidality, as well as to test the moderating effect of self-esteem in the mediation model. METHODS: A total of 3,003 adolescents from Han, Tibetan, and Yi ethnic groups living in Western China were included in this study. Utilizing the structural equation model, a mediation model and a moderated mediation model were constructed. RESULTS: The presence of NLEs was positively associated with suicidality (ß = 0.17, p < 0.001). Depressive symptoms partially mediated the relationship between NLEs and suicidality (indirect effect ß = 0.19, p < 0.001). Self-esteem moderated both the antecedent and subsequent segments of the mediating paths of "NLEs → depressive symptoms → suicidality" and the direct relationship between NLEs and suicidality. Among adolescents with a low level of self-esteem, the mediating effect coefficient of depressive symptoms was higher at 0.18 (95% confidence interval (CI): 0.14-0.23), in contrast to adolescents with a high level of self-esteem, where the mediating effect coefficient of depressive symptoms was 0.04 (95% CI: 0.02-0.07). CONCLUSION: NLEs are directly associated with an increased risk of suicidality and indirectly related to suicidality by increasing the risk of depressive symptoms among adolescents. Self-esteem can moderate the mediating effect of depressive symptoms and the relationship between NLEs and suicidality. The intervention strategy for preventing suicidality among adolescents who have experienced NLEs should focus on reducing depressive symptoms and improving self-esteem.

2.
Synth Syst Biotechnol ; 9(3): 594-599, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38711551

RESUMEN

Neuromorphic computing has the potential to achieve the requirements of the next-generation artificial intelligence (AI) systems, due to its advantages of adaptive learning and parallel computing. Meanwhile, biocomputing has seen ongoing development with the rise of synthetic biology, becoming the driving force for new generation semiconductor synthetic biology (SemiSynBio) technologies. DNA-based biomolecules could potentially perform the functions of Boolean operators as logic gates and be used to construct artificial neural networks (ANNs), providing the possibility of executing neuromorphic computing at the molecular level. Herein, we briefly outline the principles of neuromorphic computing, describe the advances in DNA computing with a focus on synthetic neuromorphic computing, and summarize the major challenges and prospects for synthetic neuromorphic computing. We believe that constructing such synthetic neuromorphic circuits will be an important step toward realizing neuromorphic computing, which would be of widespread use in biocomputing, DNA storage, information security, and national defense.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38718304

RESUMEN

In order to realize the prevailing artificial intelligence technology, memristor-implemented in-memory or neuromorphic computing is highly expected to break the bottleneck of von Neumann computers. Although high-performance memristors have been vigorously developed in labs or in industry, systematic computational investigations on memristors are seldom. Hence, it is urgent to provide theoretical or computational support for the exploration of memristor operating mechanisms or the screening of memristor materials. Here, a computational method based on the main input parameters learned from the first-principles calculations was developed to measure resistance switching of two-terminal memristors with sandwiched metal/ferroelectric semiconductor/metal architectures, which strikingly agrees with the experimental measurements. Based on our developed method, the diverse multiterminal memristors were designed to fully exploit the application of interlocked ferroelectricity of a ferroelectric semiconductor and realize their heterosynaptic plasticity, and their heterosynaptic behaviors can still be well described. Our developed method can provide a paradigm for the emulation of ferroelectric memristors and inspire subsequent computational exploration. Furthermore, our study also supplies a device optimization strategy based on the interlocked ferroelectricity and easy processing of two-dimensional van der Waals ferroelectric semiconductors, and our proposed heterosynaptic memristors still await further experimental exploration.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38712546

RESUMEN

We report on the latest advancements in Microcrystal Electron Diffraction (3D ED/MicroED), as discussed during a symposium at the National Center for CryoEM Access and Training housed at the New York Structural Biology Center. This snapshot describes cutting-edge developments in various facets of the field and identifies potential avenues for continued progress. Key sections discuss instrumentation access, research applications for small molecules and biomacromolecules, data collection hardware and software, data reduction software, and finally reporting and validation. 3D ED/MicroED is still early in its wide adoption by the structural science community with ample opportunities for expansion, growth, and innovation.

5.
Front Pharmacol ; 15: 1296075, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38708084

RESUMEN

The metabolic disease hyperuricemia (HUA) is caused by presence of excessive serum uric acid (UA), which leads to an increased risk of chronic kidney disease and gout. As a widely used traditional Chinese medicine, Euodiae fructus (ER) has strong anti-inflammatory and analgesic effects, however, its therapeutic effects on HUA and gout have not been investigated. To investigate the potential effects and underlying mechanisms, the effect of ER on proinflammatory cytokines and NLRP3 inflammasome activation was studied in mouse bone marrow macrophages. Moreover, a mouse model of HUA and gouty arthritis was established by coadministration of potassium oxonate (PO) and monosodium urate crystals to mice fed a high-fat diet (HFD) for 37 consecutive days. Oral administration of ER aqueous extract was given 1 hour later after the injection of PO for 10 days. Our study showed that ER is a powerful NLRP3 inhibitor in mouse macrophages. Most importantly, ER (0.75 g/kg) treatment substantially decreased the ankle joint thickness ratio, serum UA, creatinine and blood urea nitrogen levels (p < 0.05). Additionally, ER (0.75 g/kg) dramatically reversed the increases in renal urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) as well as the decreases in organic anion transporter 1 (OAT1) and ATP binding cassette subfamily G member 2 (ABCG2) levels (p < 0.05). Moreover, ER (0.75 g/kg) markedly ameliorated the production of the serum inflammatory cytokines IL-1ß and TNF-α (p < 0.01), and improved the activation of NLRP3 inflammasome signaling in the kidneys. Taken together, these data indicate that ER, a powerful and specific NLRP3 inhibitor, has multiple anti-HUA, anti-gout and anti-inflammatory effects. Our investigation is designed to experimentally support the conventional use of ER-containing classical herbal formulas in the treatment of HUA-related disorders and may add a new dimension to the clinical application of ER.

7.
Clin Rheumatol ; 43(5): 1551-1558, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38578510

RESUMEN

OBJECTIVE: To identify risk factors for the development of non-thyroidal illness syndrome (NTIS) in patients with systemic lupus erythematosus (SLE). METHODS: A retrospective analysis of 517 SLE patients and 1034 age-and sex-matched healthy population was conducted to compare the prevalence of NTIS in these two groups, and to analyze the laboratory and clinical characteristics of SLE patients with NTIS. Finally Logistic regression analysis was used to determine the risk factors for NTIS in SLE patients. RESULTS: The prevalence of NTIS in the SLE patients was significantly higher than that in controls (39.7% vs. 1.0%, P < 0.001). In SLE patients, compared with euthyroidism patients, NTIS patients exhibited higher levels of neutrophils, hepatic enzymes, kidney damage markers, inflammatory markers and SLE disease activity index (SLEDAI). They also had a higher incidence of organ insufficiency and positive antibodies such as anti-ds-DNA antibodies and anti-SSA antibodies. However, NTIS patients had lower levels of hemoglobin, lymphocytes, platelets, serum albumin, and complement. Additionally, NTIS patients had a shorter duration of lupus and lower utilization of disease-modifying antirheumatic drugs (DMARDs) (P < 0.05). Logistic regression analysis showed that elevated SLEDAI (OR = 1.060, 95%CI 1.022-1.099, P = 0.002), elevated systemic immune-inflammation index (SII) (OR = 1.003, 95%CI 1.001-1.007, P = 0.026), elevated erythrocyte sedimentation rate (ESR) (OR = 1.019, 95%CI 1.010-1.028, P < 0.001), and hepatic insufficiency (OR = 1.916, 95% CI 1.173-3.131, P = 0.009) were independent risk factors for the development of NTIS in SLE. DMARDs treatment (OR = 0.495, 95% CI 0.306-0.799, P < 0.001) was an independent protective factor for NTIS. CONCLUSIONS: Inflammatory activity in SLE patients is associated with the development of NTIS. Key Points • Inflammatory activity indexes such as SLEDAI, SII, and ESR are independent risk factors for NTIS in SLE patients.


Asunto(s)
Antirreumáticos , Lupus Eritematoso Sistémico , Humanos , Estudios Retrospectivos , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/epidemiología , Inflamación/complicaciones , Linfocitos , Antirreumáticos/uso terapéutico , Índice de Severidad de la Enfermedad
8.
BMJ Open ; 14(4): e080734, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38643015

RESUMEN

OBJECTIVE: To explore the knowledge, attitudes and practice (KAP) towards the postoperative nursing of patients with digit replantation and skin flap transplantation among new nurses. DESIGN: Cross-sectional survey. SETTING: Two tertiary medical centres in Beijing, China. PARTICIPANTS: New nurses with working experience within 2 years. PRIMARY AND SECONDARY OUTCOME MEASURES: The demographic characteristics of the nurses and their KAP towards the postoperative nursing of patients with digit replantation and skin flap transplantation were collected using a self-administered questionnaire. The primary outcome was the KAP scores towards the postoperative nursing of patients with digit replantation and skin flap transplantation. The secondary outcomes were the factors associated with the KAP scores and how the KAP dimensions interacted among them. RESULTS: A total of 206 valid questionnaires were collected. The mean KAP scores were 7.72±3.28 (total score 13; 59.3%), 37.95±6.05 (total score 50; 75.9%) and 38.23±6.12 (total score 45; 84.9%), indicating poor knowledge, moderately favourable attitudes and active practice. The structural equation model analysis showed that knowledge directly influences attitudes (ß=0.82, 95%CI 0.60 to 1.05, p<0.001) and that attitudes directly influence practices (ß=0.72, 95%CI 0.62 to 0.83, p<0.001). Knowledge had no direct influence on practices (ß=0.10, 95%CI -0.09 to 0.29, p=0.313), but the indirect influence was significant (ß=0.60, 95%CI 0.41 to 0.78, p<0.001). CONCLUSION: The lack of sufficient knowledge towards the postoperative nursing of patients with digit replantation and skin flap transplantation among nurses with <2 years of experience and the correlation among the KAP dimensions suggested the importance of proper training.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Reimplantación , Humanos , Estudios Transversales , Beijing , Encuestas y Cuestionarios
10.
Plant J ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38662911

RESUMEN

Carotenoids are photosynthetic pigments and antioxidants that contribute to different plant colors. However, the involvement of TOPLESS (TPL/TPR)-mediated histone deacetylation in the modulation of carotenoid biosynthesis through ethylene-responsive element-binding factor-associated amphiphilic repression (EAR)-containing transcription factors (TFs) in apple (Malus domestica Borkh.) is poorly understood. MdMYB44 is a transcriptional repressor that contains an EAR repression motif. In the present study, we used functional analyses and molecular assays to elucidate the molecular mechanisms through which MdMYB44-MdTPR1-mediated histone deacetylation influences carotenoid biosynthesis in apples. We identified two carotenoid biosynthetic genes, MdCCD4 and MdCYP97A3, that were confirmed to be involved in MdMYB44-mediated carotenoid biosynthesis. MdMYB44 enhanced ß-branch carotenoid biosynthesis by repressing MdCCD4 expression, whereas MdMYB44 suppressed lutein level by repressing MdCYP97A3 expression. Moreover, MdMYB44 partially influences carotenoid biosynthesis by interacting with the co-repressor TPR1 through the EAR motif to inhibit MdCCD4 and MdCYP97A3 expression via histone deacetylation. Our findings indicate that the MdTPR1-MdMYB44 repressive cascade regulates carotenoid biosynthesis, providing profound insights into the molecular basis of histone deacetylation-mediated carotenoid biosynthesis in plants. These results also provide evidence that the EAR-harboring TF/TPL repressive complex plays a universal role in histone deacetylation-mediated inhibition of gene expression in various plants.

11.
China CDC Wkly ; 6(14): 300-304, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38634101
12.
Genome Med ; 16(1): 47, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566132

RESUMEN

BACKGROUND: Aberrant DNA methylation is a major characteristic of cancer genomes. It remains unclear which biological processes determine epigenetic reprogramming and how these processes influence the variants in the cancer methylome, which can further impact cancer phenotypes. METHODS: We performed pairwise permutations of 381,900 loci in 569 paired DNA methylation profiles of cancer tissue and matched normal tissue from The Cancer Genome Atlas (TCGA) and defined conserved differentially methylated positions (DMPs) based on the resulting null distribution. Then, we derived independent methylation signatures from 2,465 cancer-only methylation profiles from the TCGA and 241 cell line-based methylation profiles from the Genomics of Drug Sensitivity in Cancer (GDSC) cohort using nonnegative matrix factorization (NMF). We correlated DNA methylation signatures with various clinical and biological features, including age, survival, cancer stage, tumor immune microenvironment factors, and immunotherapy response. We inferred the determinant genes of these methylation signatures by integrating genomic and transcriptomic data and evaluated the impact of these signatures on cancer phenotypes in independent bulk and single-cell RNA/methylome cohorts. RESULTS: We identified 7,364 differentially methylated positions (2,969 Hyper-DMPs and 4,395 Hypo-DMPs) in nine cancer types from the TCGA. We subsequently retrieved three highly conserved, independent methylation signatures (Hyper-MS1, Hypo-MS1, and Hypo-MS4) from cancer tissues and cell lines based on these Hyper and Hypo-DMPs. Our data suggested that Hypo-MS4 activity predicts poor survival and is associated with immunotherapy response and distant tumor metastasis, and Hypo-MS4 activity is related to TP53 mutation and FOXA1 binding specificity. In addition, we demonstrated a correlation between the activities of Hypo-MS4 in cancer cells and the fractions of regulatory CD4 + T cells with the expression levels of immunological genes in the tumor immune microenvironment. CONCLUSIONS: Our findings demonstrated that the methylation signatures of distinct biological processes are associated with immune activity in the cancer microenvironment and predict immunotherapy response.


Asunto(s)
Metilación de ADN , Neoplasias , Humanos , Epigénesis Genética , Microambiente Tumoral/genética , Neoplasias/genética , Neoplasias/terapia , Perfilación de la Expresión Génica/métodos , Pronóstico , Inmunoterapia
13.
Am J Chin Med ; 52(2): 315-354, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38553799

RESUMEN

Liver diseases and their related complications endanger the health of millions of people worldwide. The prevention and treatment of liver diseases are still serious challenges both in China and globally. With the improvement of living standards, the prevalence of metabolic liver diseases, including non-alcoholic fatty liver disease and alcoholic liver disease, has increased at an alarming rate, resulting in more cases of end-stage liver disease. Therefore, the discovery of novel therapeutic drugs for the treatment of liver diseases is urgently needed. Glycyrrhizin (GL), a triterpene glycoside from the roots of licorice plants, possesses a wide range of pharmacological and biological activities. Currently, GL preparations (GLPs) have certain advantages in the treatment of liver diseases, with good clinical effects and fewer adverse reactions, and have shown broad application prospects through multitargeting therapeutic mechanisms, including antisteatotic, anti-oxidative stress, anti-inflammatory, immunoregulatory, antifibrotic, anticancer, and drug interaction activities. This review summarizes the currently known biological activities of GLPs and their medical applications in the treatment of liver diseases, and highlights the potential of these preparations as promising therapeutic options and their alluring prospects for the treatment of liver diseases.


Asunto(s)
Ácido Glicirrínico , Hepatopatías , Humanos , Ácido Glicirrínico/farmacología , Ácido Glicirrínico/uso terapéutico , Hepatopatías/tratamiento farmacológico , Antiinflamatorios/uso terapéutico , Antiinflamatorios/farmacología , Estrés Oxidativo
14.
Food Funct ; 15(8): 4170-4179, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38482855

RESUMEN

Premenstrual disorders (PMDs) are common among young women and have been linked to metabolic dysfunction. Limited evidence exists regarding the associations between dietary patterns and PMDs. This cross-sectional study involved young female adults recruited from the Care of Premenstrual Emotion (COPE) cohort study in China to examine the relationship between dietary patterns and PMDs in young adulthood. PMDs were assessed using the Calendar of Premenstrual Experiences, and the consumption frequency of 12 common food groups was evaluated using a Food Frequency Questionnaire. We used principal component analysis to identify the dietary patterns and employed logistic regression to investigate the association between dietary pattern adherence and PMDs. The study included 1382 participants, of whom 337 (24.4%) reported having PMDs. Three dietary patterns were identified and named based on regional food preferences: the Traditional North China Diet (TNCD), the Traditional South China Diet (TSCD), and the Lacto-ovo Vegetarian Diet (LVD). The TSCD, characterized by high consumption of rice, red meat, and poultry, showed a significant inverse association with PMDs. This pattern held good for both premenstrual syndrome and premenstrual dysphoric disorder. These findings suggest that targeted dietary modifications could serve as a localized strategy for PMDs prevention.


Asunto(s)
Dieta , Síndrome Premenstrual , Estudiantes , Humanos , Femenino , China/epidemiología , Estudios Transversales , Adulto Joven , Síndrome Premenstrual/epidemiología , Estudiantes/psicología , Adulto , Adolescente , Encuestas y Cuestionarios , Universidades , Conducta Alimentaria , Preferencias Alimentarias , Patrones Dietéticos
15.
Mol Nutr Food Res ; 68(8): e2300797, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38549456

RESUMEN

SCOPE: l-Theanine (l-Thea) is an amino acid which is naturally present in tea leaves. It has been associated with possible health advantages, including obesity prevention, but the underlying molecular mechanisms have not been elucidated. METHODS AND RESULTS: A multiomics approach is utilized to examine the mechanism by which l-Thea exerts its antiobesity effects. This study reveals that l-Thea administration significantly ameliorates high-fat diet (HFD)-induced obesity in rats by improving body weight and hyperlipidemia. l-Thea mitigates HFD-induced inflammation and reverses hepatic and colonic damage, and intestinal barrier. This research verifies that the preventive effect of l-Thea on obesity in rats induced by an HFD with colitis is accomplished by suppressing the phosphorylation of important proteins in the NF-κB/mitogen-activated protein kinase (MAPK) pathways. Metabolome analysis reveals that l-Thea regulates HFD-induced metabolic disorders, specifically through modulation of steroid hormone biosynthesis. Microbiome analysis reveals that l-Thea mitigates HFD-induced dysbiosis by increasing the relative abundance of obesity-associated probiotic bacteria, including Blautia coccoides and Lactobacillus murinus, while simultaneously suppressing the abundance of pathogenic bacteria. CONCLUSIONS: l-Thea alleviates colitis generated by an HFD by restoring the integrity of the intestinal barrier, suppressing inflammation through regulation of MAPK/NF-κB signaling pathways, and enhancing microbial metabolism in colon.


Asunto(s)
Colon , Dieta Alta en Grasa , Obesidad , Animales , Masculino , Ratas , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colon/efectos de los fármacos , Colon/metabolismo , Dieta Alta en Grasa/efectos adversos , Disbiosis , Microbioma Gastrointestinal/efectos de los fármacos , Glutamatos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , FN-kappa B/metabolismo , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos
16.
Diabetes Metab Syndr Obes ; 17: 1093-1103, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38450416

RESUMEN

Background: The monocyte-to-high-density lipoprotein cholesterol (MHR) ratio has been linked to metabolic disorders. However, there is limited research on the predisposition to MHR and prediabetes. Hence, we conducted a study to investigate the relationship between MHR and the prevalence of prediabetes. Methods: In total, 85,293 participants were included in our cross-sectional observational study. Multivariable regression analysis, subgroup analyses, and interaction testing were used to determine the relationship between MHR and prediabetes. To explore the non-linear association of MHR with prediabetes risk, generalized additive model (GAM) and smoothing splines were applied. The threshold effect analysis of MHR on the risk of prediabetes was further employed to identify the turning point. Results: After controlling for covariates, the results indicated that a positive correlation persisted between MHR and prediabetes (odds ratio (OR) =1.64, 95% confidence interval (CI), 1.48-1.82), and subgroup analyses found a more robust correlation between MHR and prediabetes in individuals with lower age, SBP, DBP, TG, TC and higher values of BMI and LDL-C than in their counterparts. Additionally, the correlation between MHR and the risk of prediabetes was found to be non-linear, with a turning point of -0.4 (Log-Likelihood Ratio, P< 0.001). The impact of variables on the two sides of the turning point were 1.94 (1.72, 2.19) and 0.88 (0.69, 1.14). Conclusion: The positive correlation between MHR and the risk of prediabetes in Chinese participants was observed to be non-linear, and MHR ≤ -0.4 was strongly positively correlated with prediabetes risk.

17.
Adv Sci (Weinh) ; : e2309557, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38516754

RESUMEN

Digital PCR (dPCR) holds immense potential for precisely detecting nucleic acid markers essential for personalized medicine. However, its broader application is hindered by high consumable costs, complex procedures, and restricted multiplexing capabilities. To address these challenges, an all-in-one dPCR system is introduced that eliminates the need for microfabricated chips, offering fully automated operations and enhanced multiplexing capabilities. Using this innovative oscillation-induced droplet generation technique, OsciDrop, this system supports a comprehensive dPCR workflow, including precise liquid handling, pipette-based droplet printing, in situ thermocycling, multicolor fluorescence imaging, and machine learning-driven analysis. The system's reliability is demonstrated by quantifying reference materials and evaluating HER2 copy number variation in breast cancer. Its multiplexing capability is showcased with a quadruplex dPCR assay that detects key EGFR mutations, including 19Del, L858R, and T790M in lung cancer. Moreover, the digital stepwise melting analysis (dSMA) technique is introduced, enabling high-multiplex profiling of seven major EGFR variants spanning 35 subtypes. This innovative dPCR system presents a cost-effective and versatile alternative, overcoming existing limitations and paving the way for transformative advances in precision diagnostics.

18.
Environ Sci Technol ; 58(10): 4606-4616, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38427797

RESUMEN

Transforming hazardous species into active sites by ingenious material design was a promising and positive strategy to improve catalytic reactions in industrial applications. To synergistically address the issue of sluggish CO2 desorption kinetics and SO2-poisoning solvent of amine scrubbing, we propose a novel method for preparing a high-performance core-shell C@Mn3O4 catalyst for heterogeneous sulfur migration and in situ reconstruction to active -SO3H groups, and thus inducing an enhanced proton-coupled electron transfer (PCET) effect for CO2 desorption. As anticipated, the rate of CO2 desorption increases significantly, by 255%, when SO2 is introduced. On a bench scale, dynamic CO2 capture experiments reveal that the catalytic regeneration heat duty of SO2-poisoned solvent experiences a 32% reduction compared to the blank case, while the durability of the catalyst is confirmed. Thus, the enhanced PCET of C@Mn3O4, facilitated by sulfur migration and simultaneous transformation, effectively improves the SO2 resistance and regeneration efficiency of amine solvents, providing a novel route for pursuing cost-effective CO2 capture with an amine solvent.


Asunto(s)
Dióxido de Carbono , Protones , Electrones , Solventes , Aminas , Azufre
19.
Biochem Biophys Res Commun ; 704: 149723, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38430698

RESUMEN

Subclinical hyperthyroidism is defined biochemically as a low or undetectable thyroid-stimulating hormone (TSH) with normal thyroid hormone levels. Low TSHR signaling is considered to associate with cognitive impairment. However, the underlying molecular mechanism by which TSHR signaling modulates memory is poorly understood. In this study, we found that Tshr-deficient in the hippocampal neurons impairs the learning and memory abilities of mice, accompanying by a decline in the number of newborn neurons. Notably, Tshr ablation in the hippocampus decreases the expression of Wnt5a, thereby inactivating the ß-catenin signaling pathway to reduce the neurogenesis. Conversely, activating of the Wnt/ß-catenin pathway by the agonist SKL2001 results in an increase in hippocampal neurogenesis, resulting in the amelioration in the deficits of memory caused by Tshr deletion. Understanding how TSHR signaling in the hippocampus regulates memory provides insights into subclinical hyperthyroidism affecting cognitive function and will suggest ways to rationally design interventions for neurocognitive disorders.


Asunto(s)
Hipertiroidismo , beta Catenina , Ratones , Animales , beta Catenina/metabolismo , Receptores de Tirotropina/genética , Receptores de Tirotropina/metabolismo , Vía de Señalización Wnt/fisiología , Receptores Acoplados a Proteínas G/metabolismo , Hipocampo/metabolismo , Neurogénesis/fisiología , Hipertiroidismo/metabolismo
20.
Plant Physiol ; 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38536032

RESUMEN

Carotenoids are major pigments contributing to fruit coloration. We previously reported that the apple (Malus domestica Borkh.) mutant fruits of 'Beni Shogun' and 'Yanfu 3' show a marked difference in fruit coloration. However, the regulatory mechanism underlying this phenomenon remains unclear. In this study, we determined that carotenoid is the main factor influencing fruit flesh color. We identified an R1-type MYB transcription factor, MdMYBS1, which was found to be highly associated with carotenoids and abscisic acid (ABA) contents of apple fruits. Overexpression of MdMYBS1 promoted, and silencing of MdMYBS1 repressed, ß-branch carotenoids synthesis and ABA accumulation. MdMYBS1 regulates carotenoid biosynthesis by directly activating the major carotenoid biosynthetic genes encoding phytoene synthase (MdPSY2-1) and lycopene ß-cyclase (MdLCYb). 9-cis-epoxycarotenoid dioxygenase 1 (MdNCED1) contributes to ABA biosynthesis, and MdMYBS1 enhances endogenous ABA accumulation by activating the MdNCED1 promoter. In addition, the basic leucine zipper domain transcription factor ABSCISIC ACID-INSENSITIVE5 (MdABI5) was identified as an upstream activator of MdMYBS1, which promotes carotenoid and ABA accumulation. Furthermore, ABA promotes carotenoid biosynthesis and enhances MdMYBS1 and MdABI5 promoter activities. Our findings demonstrate that the MdABI5-MdMYBS1 cascade activated by ABA regulates carotenoid-derived fruit coloration and ABA accumulation in apple, providing avenues in breeding and planting for improvement of fruit coloration and quality.

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