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1.
Nat Commun ; 15(1): 5940, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009563

RESUMO

Eunicellane diterpenoids, containing a typical 6,10-bicycle, are bioactive compounds widely present in marine corals, but rarely found in bacteria and plants. The intrinsic macrocycle exhibits innate structural flexibility resulting in dynamic conformational changes. However, the mechanisms controlling flexibility remain unknown. The discovery of a terpene synthase, MicA, that is responsible for the biosynthesis of a nearly non-flexible eunicellane skeleton, enable us to propose a feasible theory about the flexibility in eunicellane structures. Parallel studies of all eunicellane synthases in nature discovered to date, including 2Z-geranylgeranyl diphosphate incubations and density functional theory-based Boltzmann population computations, reveale that a trans-fused bicycle with a 2Z-configuration alkene restricts conformational flexibility resulting in a nearly non-flexible eunicellane skeleton. The catalytic route and the enzymatic mechanism of MicA are also elucidated by labeling experiments, density functional theory calculations, structural analysis of the artificial intelligence-based MicA model, and mutational studies.


Assuntos
Alquil e Aril Transferases , Diterpenos , Alquil e Aril Transferases/metabolismo , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/química , Diterpenos/metabolismo , Diterpenos/química , Fosfatos de Poli-Isoprenil/metabolismo , Fosfatos de Poli-Isoprenil/química , Modelos Moleculares
2.
Curr Eye Res ; : 1-9, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38979820

RESUMO

PURPOSE: To investigate the effect of reducing Lysyl oxidase (LOX) overexpression on retinal ganglion cells (RGCs) apoptosis in an acute ocular hypertension (AOH) rat model. METHODS: AOH rat model was performed by anterior chamber perfusion and either received an intravitreal injection with ß-aminopropionitrile (BAPN) or normal saline. After 2wk, Quantification of survival RGCs in the retina was performed using Retrograde FluoroGold labeling. The mRNA expression levels of LOX, LOXL1-4, collagen 1a1 (Col1a1), collagen 3a1 (Col3a1), collagen4a1 (Col4a1), elastin (Eln), fibronectin1 (Fbn1), fibronectin4 (Fbn4) were determined by RT-qPCR. LOX expression was determined by Western blot (WB) analysis and immunohistochemistry. The RNA expression of LOX, Eln and Col1a1 in RGCs retrograde-labeled with 1,1'-dioctadecyl-3,3,3',3' tetra-methylindocarbocyanine perchlorate(DiI)that selected through FACS sorting were determined by RT-qPCR analysis. Changes of the retinal function were detected by Electroretinogram (ERG) analysis. RESULTS: Results showed that significant LOX overexpression and loss of RGCs related to IOP exposure in AOH retinas. PCR analysis indicated significant increased mRNA level of Col1a1, Col3al and Eln in AOH retinas. Significant increase mRNA expression of LOX, Col1a1 and Eln in the RGCs were observed in AOH group compared with CON group. AOH rats injected with BAPN showed a significant decrease in LOX expression, reduced the loss of RGCs and retinal function damage. CONCLUSIONS: The results demonstrated that changes of LOX and specific ECM components in retina were correlated with AOH. Findings from this study indicated that preventing LOX over-expression may be protective against RGCs loss and retinal function damage in AOH animal model.

3.
Psychol Res Behav Manag ; 17: 2545-2555, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38973973

RESUMO

Introduction: The surge in mobile gaming, fueled by smartphone and internet accessibility, lacks a comprehensive understanding of physiological changes during gameplay. Methods: This study, involving 93 participants (average age 21.75 years), categorized them into Problematic Mobile Gaming (PMG) and non-problematic Mobile Gaming (nPMG) groups based on Problematic Mobile Gaming Questionnaire (PMGQ) scores. The PMGQ is a 12-item scale developed in Taiwan to assess symptoms of problematic mobile gaming. The research delved into heart rate variability (HRV) alterations during real-time mobile gaming and self-gaming video viewing. Results: Results showed that the PMG group significantly presents a lower root mean square of successive differences (RMSSD), and High Frequency (lnHF) than does the nPMG group (F=4.73, p=0.03; F=10.65, p=0.002, respectively) at the baseline. In addition, the PMG group significantly displayed elevated HF and low-frequency to high-frequency (LF/HF) in the mobile-gaming (F=7.59, p=0.007; F=9.31, p=0.003) condition as well as in the watching self-gaming videos (F=9.75, p=0.002; F=9.02, p=0.003) than did the nPMG. Conclusion: The study suggests targeted interventions to mitigate autonomic arousal, offering a potential avenue to address adverse effects associated with problematic mobile gaming behavior. The PMG group displayed increased craving scores after real-time mobile gaming and watching self-gaming video excerpts, unlike the nPMG group. Elevated LF/HF ratios in frequent gaming cases heightened autonomic arousal, presenting challenges in relaxation after mobile gaming. These findings contribute to a nuanced understanding of the complex interplay between mobile gaming activities, physiological responses, and potential intervention strategies.

4.
Biomed Environ Sci ; 37(6): 647-660, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38988115

RESUMO

Toxoplasma gondii( T. gondii or Tg), is an obligatory intracellular parasite with humans as its intermediate hosts. In recent years, significant correlations between T. gondii infection and schizophrenia have been reported, including the possible mediating mechanisms. Currently, mechanisms and hypotheses focus on central neurotransmitters, immunity, neuroinflammation, and epigenetics; however, the exact underlying mechanisms remain unclear. In this article, we review the studies related to T. gondii infection and schizophrenia, particularly the latest research progress. Research on dopamine (DA) and other neurotransmitters, the blood-brain barrier, inflammatory factors, disease heterogeneity, and other confounders is also discussed. In addition, we also summarized the results of some new epidemiological investigations.


Assuntos
Esquizofrenia , Toxoplasma , Toxoplasmose , Esquizofrenia/parasitologia , Esquizofrenia/etiologia , Humanos , Toxoplasmose/complicações , Toxoplasmose/epidemiologia , Toxoplasmose/parasitologia , Animais
5.
Sci Rep ; 14(1): 16835, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039134

RESUMO

This study investigated the predictive factors for perinatal bacterial transmission in very-low-birth-weight infants (VLBWIs) born to mothers with a history of intrapartum colonization. We retrospectively reviewed the medical records of 173 VLBWIs, wherein pathogens were confirmed in maternal cultures obtained from the blood, urine, and vagina during the intrapartum period from 2013 to 2020. Newborns were categorized based on microbiological tests, including gastric aspirates, endotracheal aspirates, blood, and skin/nasal swab cultures collected immediately after birth. Infants whose cultures matched their maternal pathogens were categorized into the "transmission group" (n = 45), while those who tested negative were assigned to the "control group" (n = 128). The predominant maternal-colonizing pathogen observed was Escherichia coli (30.6%), which also emerged as the primary colonizing pathogen in neonates (35.6%). Transmission group had higher incidences of maternal leukocytosis, chorioamnionitis, and cervical cerclage. Regarding neonatal characteristics, the transmission group demonstrated lower initial base excesses (- 6.3 ± 3.9 vs. - 9.2 ± 4.9, P < 0.05) and higher C-reactive protein levels (0.1 ± 0.3 vs. 0.4 ± 0.8, P < 0.05). Notably, regarding major neonatal outcomes, transmission group had higher mortality rates and incidences of severe intraventricular hemorrhage. These findings may be useful for making decisions when considering antibiotic treatment for infants with a history of maternal colonization.


Assuntos
Recém-Nascido de muito Baixo Peso , Transmissão Vertical de Doenças Infecciosas , Humanos , Feminino , Recém-Nascido , Estudos Retrospectivos , Gravidez , Masculino , Adulto , Complicações Infecciosas na Gravidez/microbiologia , Mães , Fatores de Risco , Escherichia coli/isolamento & purificação
6.
Radiology ; 312(1): e240273, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38980179

RESUMO

Background The diagnostic abilities of multimodal large language models (LLMs) using direct image inputs and the impact of the temperature parameter of LLMs remain unexplored. Purpose To investigate the ability of GPT-4V and Gemini Pro Vision in generating differential diagnoses at different temperatures compared with radiologists using Radiology Diagnosis Please cases. Materials and Methods This retrospective study included Diagnosis Please cases published from January 2008 to October 2023. Input images included original images and captures of the textual patient history and figure legends (without imaging findings) from PDF files of each case. The LLMs were tasked with providing three differential diagnoses, repeated five times at temperatures 0, 0.5, and 1. Eight subspecialty-trained radiologists solved cases. An experienced radiologist compared generated and final diagnoses, considering the result correct if the generated diagnoses included the final diagnosis after five repetitions. Accuracy was assessed across models, temperatures, and radiology subspecialties, with statistical significance set at P < .007 after Bonferroni correction for multiple comparisons across the LLMs at the three temperatures and with radiologists. Results A total of 190 cases were included in neuroradiology (n = 53), multisystem (n = 27), gastrointestinal (n = 25), genitourinary (n = 23), musculoskeletal (n = 17), chest (n = 16), cardiovascular (n = 12), pediatric (n = 12), and breast (n = 5) subspecialties. Overall accuracy improved with increasing temperature settings (0, 0.5, 1) for both GPT-4V (41% [78 of 190 cases], 45% [86 of 190 cases], 49% [93 of 190 cases], respectively) and Gemini Pro Vision (29% [55 of 190 cases], 36% [69 of 190 cases], 39% [74 of 190 cases], respectively), although there was no evidence of a statistically significant difference after Bonferroni adjustment (GPT-4V, P = .12; Gemini Pro Vision, P = .04). The overall accuracy of radiologists (61% [115 of 190 cases]) was higher than that of Gemini Pro Vision at temperature 1 (T1) (P < .001), while no statistically significant difference was observed between radiologists and GPT-4V at T1 after Bonferroni adjustment (P = .02). Radiologists (range, 45%-88%) outperformed the LLMs at T1 (range, 24%-75%) in most subspecialties. Conclusion Using direct radiologic image inputs, GPT-4V and Gemini Pro Vision showed improved diagnostic accuracy with increasing temperature settings. Although GPT-4V slightly underperformed compared with radiologists, it nonetheless demonstrated promising potential as a supportive tool in diagnostic decision-making. © RSNA, 2024 See also the editorial by Nishino and Ballard in this issue.


Assuntos
Radiologistas , Humanos , Estudos Retrospectivos , Diagnóstico Diferencial , Interpretação de Imagem Assistida por Computador/métodos , Feminino
7.
J Sex Res ; : 1-16, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38905162

RESUMO

Motivations for pornography use may vary across gender identities, sexual orientations, and geographical regions, warranting examination to promote individual and public health. The aims of this study were to validate the Pornography Use Motivations Scale (PUMS) in a diverse, multicultural sample, and develop a short form (PUMS-8) that can assess a wide range of pornography use motivations. Using data from 42 countries (N = 75,117; Mage = 32.07; SDage = 12.37), enabled us to thoroughly evaluate the dimensionality, validity, and reliability of the Pornography Use Motivations Scale (PUMS), leading to the development of the more concise PUMS-8 short scale. Additionally, language-, nationality-, gender-, and sexual-orientation-based measurement invariance tests were conducted to test the comparability across groups. Both the PUMS and the PUMS-8 assess eight pornography use motivations, and both demonstrated excellent psychometric properties. Sexual Pleasure emerged as the most frequent motivation for pornography use across countries, genders, and sexual orientations, while differences were observed concerning other motivations (e.g. self-exploration was more prevalent among gender-diverse individuals than men or women). The motivational background of pornography use showed high similarity in the examined countries. Both the PUMS and the PUMS-8 are reliable and valid measurement tools to assess different types of motivations for pornography use across countries, genders, and sexual orientations. Both scales are recommended for use in research and clinical settings.

8.
Microorganisms ; 12(6)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38930536

RESUMO

Licorice (Glycyrrhiza glabra) is a plant of the genus Glycyrrhiza in the family Fabaceae/Leguminosae and is a renowned natural herb with a long history of medicinal use dating back to ancient times. Glycyrrhizin (GLY), the main active component of licorice, serves as a widely utilized therapeutic agent in clinical practice. GLY exhibits diverse medicinal properties, including anti-inflammatory, antibacterial, antiviral, antitumor, immunomodulatory, intestinal environment maintenance, and liver protection effects. However, current research primarily emphasizes GLY's antiviral activity, while providing limited insight into its antibacterial properties. GLY demonstrates a broad spectrum of antibacterial activity via inhibiting the growth of bacteria by targeting bacterial enzymes, impacting cell membrane formation, and altering membrane permeability. Moreover, GLY can also bolster host immunity by activating pertinent immune pathways, thereby enhancing pathogen clearance. This paper reviews GLY's inhibitory mechanisms against various pathogenic bacteria-induced pathological changes, its role as a high-mobility group box 1 inhibitor in immune regulation, and its efficacy in combating diseases caused by pathogenic bacteria. Furthermore, combining GLY with other antibiotics reduces the minimum inhibitory concentration, potentially aiding in the clinical development of combination therapies against drug-resistant bacteria. Sources of information were searched using PubMed, Web of Science, Science Direct, and GreenMedical for the keywords "licorice", "Glycyrrhizin", "antibacterial", "anti-inflammatory", "HMGB1", and combinations thereof, mainly from articles published from 1979 to 2024, with no language restrictions. Screening was carried out by one author and supplemented by others. Papers with experimental flaws in their experimental design and papers that did not meet expectations (antifungal papers, etc.) were excluded.

9.
J Med Chem ; 67(13): 10783-10794, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38888591

RESUMO

Marine natural product (MNP) pretrichodermamide B (Pre B, 9) was identified as a novel STAT3 inhibitor in our previous work, while its metabolic instability hindered its further development. To address this drawback, ligand structure-based drug design was adopted leading to a series of Pre B derivatives. Among them, MNP trichodermamide B (tri B, 24) obtained by skeletal rearrangement exhibited more potent antiproliferative activity with an IC50 value of 0.12 µM against HCT116. Notably, 24 stood out with improved metabolic stability (T1/2 = 31 min) and more favorable oral bioavailability (F = 37.5%). Further studies indicated that 24 blocked JAK/STAT3 signaling in dose- and time-dependent manner. In vivo, 24 suppressed tumor growth (TGI = 65%) at a dose of 20 mg/kg in a HCT116-derived xenograft mouse model. Overall, 24 might be a promising lead compound for colon cancer and is worthy of further investigation.


Assuntos
Antineoplásicos , Produtos Biológicos , Neoplasias do Colo , Janus Quinases , Fator de Transcrição STAT3 , Transdução de Sinais , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Antineoplásicos/uso terapêutico , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Produtos Biológicos/síntese química , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Janus Quinases/antagonistas & inibidores , Janus Quinases/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
10.
J Korean Soc Radiol ; 85(3): 654-660, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38873381

RESUMO

Primary malignant fibrous histiocytoma (MFH) is a malignant tumor of mesenchymal origin that rarely occurs in the urinary tract, particularly in the urinary bladder. Unlike urothelial carcinoma, which accounts for most bladder cancers, it occurs in the submucosal portion of the bladder wall and consists of the lamina propria, muscularis propria, and adventitia. It is presumed to originate from poorly differentiated pluripotent mesenchymal cells in which fibroblasts and histiocytes are partially differentiated. Radiologically, it is known as the "non-papillary tumor" and is commonly diagnosed as a large mass without necrosis, which shows invasion beyond the muscularis propia. Although the prognosis of this rare malignancy depends on pathological parameters, it generally has a poor prognosis with high local tumor recurrence. Here, we present a case of primary MFH in the urinary bladder with clinical symptoms of lower abdominal pain without gross hematuria that recurred rapidly and showed an aggressive disease course.

11.
Environ Pollut ; 356: 124253, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851378

RESUMO

Bioaugmentation techniques still show drawbacks in the cleanup of total petroleum hydrocarbons (TPHs) from petroleum-contaminated site soil. Herein, this study explored high-performance immobilized bacterial pellets (IBPs) embed Microbacterium oxydans with a high degrading capacity, and developed a controlled-release oxygen composite (CROC) that allows the efficient, long-term release of oxygen. Tests with four different microcosm incubations were performed to assess the effects of IBPs and CROC on the removal of TPHs from petroleum-contaminated site soil. The results showed that the addition of IBPs and/or CROC could significantly promote the remediation of TPHs in soil. A CROC only played a significant role in the degradation of TPHs in deep soil. The combined application of IBPs and CROC had the best effect on the remediation of deep soil, and the removal rate of TPHs reached 70%, which was much higher than that of nature attenuation (13.2%) and IBPs (43.0%) or CROC (31.9%) alone. In particular, the CROC could better promote the degradation of heavy distillate hydrocarbons (HFAs) in deep soil, and the degradation rates of HFAs increased from 6.6% to 33.2%-21.0% and 67.9%, respectively. In addition, the IBPs and CROC significantly enhanced the activity of dehydrogenase, catalase, and lipase in soil. Results of the enzyme activity were the same as that of TPH degradation. The combined application of IBPs and CROC not only increased the microbial abundance and diversity of soil, but also significantly enhanced the enrichment of potential TPH-biodegrading bacteria. M. oxydans was dominant in AP (bioaugmentation with addition of IBPs) and APO (bioaugmentation with the addition of IBPs and CROC) microcosms that added IBPs. Overall, the IBPs and CROC developed in this study provide a novel option for the combination of bioaugmentation and biostimulation for remediating organic pollutants in soil.

12.
Cancers (Basel) ; 16(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38893089

RESUMO

(1) Background: Evidence suggested inconsistent results in anxiety and depression scores among female and male cancer patients. The present systematic review and meta-analysis aimed to assess how anxiety and depression conditions among cancer patients vary according to sex. (2) Methods: This systematic review and meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). The protocol was registered in PROSPERO with id no. CRD42024512553. The search strategy involved combining keywords using Boolean operators, including "Anxiety", "Cancer", and "Depression", across several databases: Embase, PubMed, Scopus, and Web of Science. The outcomes were evaluated using the Hospital Anxiety and Depression Scale (HADS). (3) Results: Data were collected from five studies, enrolling a total of 6317 cancer patients, of whom 2961 were females and 3356 males. For each study, HADS-A and HADS-D scores were considered, also differentiating HADS scores according to cancer typology, and then three different meta-analyses were performed. Generally, females reported significantly higher levels of depression scores than males and, conversely, males reported significantly greater levels of anxiety than females. (4) Conclusions: Previous studies suggested higher rates of depression and anxiety conditions in females than in males, but the present data highlighted controversial findings, since males reported significantly higher levels of anxiety than females. In this scenario, the theoretical approach justified females being more open than males to expressing anxiety or depression conditions. It would be necessary for healthcare professionals to improve effective measures purposed at assessing and mitigating depressive symptoms in cases of advanced cancer, thereby improving their mental health, given the high rates of depression in advanced cancer patients, due to the difficulty level of performing their daily living activities, which deteriorate further over time.

13.
Front Public Health ; 12: 1406524, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38894993

RESUMO

Backgrounds: Habitual substance use, i. e., alcohol, tobacco and betel nut, has been found with an increased risk of metabolic syndrome (MetS) in the general population, whereas the association remains unclear in physically fit military personnel. This study aimed to investigate the combination of these substances use and their associations with new-onset MetS in the military. Methods: A total of 2,890 military men and women, aged 18-39 years, without MetS were obtained from the cardiorespiratory fitness and health in eastern armed forces study (CHIEF) in Taiwan and followed for incident MetS from baseline (2014) through the end of 2020. Incident MetS event was defined by the International Diabetes Federation guideline and confirmed in the annual health examinations. A self-report was used to assess the alcohol, tobacco and betel nut use status (active vs. former/never). Multivariable Cox regression model was performed to determine the association with adjustments for sex, age, body mass index and physical activity at baseline. Results: At baseline, there were 279 active betel nut chewers (9.7%), 991 active smokers (34.3%) and 1,159 active alcohol consumers (40.1%). During a mean follow-up of 6.0 years, 673 incident MetS (23.3%) were observed. As compared to no substance users, only one substance, and two and three substances users had a greater risk of incident MetS [hazard ratios (HRs) and 95% confidence intervals: 1.27 (1.06-1.54), 1.38 (1.12-1.69) and 1.78 (1.37-2.32), respectively]. In subgroup analyses, the risk of incident MetS in two and three substances users was significantly greater in those free of baseline low high-density lipoprotein [HRs: 1.54 (1.21-1.95) and 2.57 (1.92-3.46), respectively], as compared to their counterparts (both p for interactions <0.05). Conclusion: A dose-response association of more substances use for new-onset MetS was noted in military personnel. This finding suggests that the combined alcohol, tobacco and betel nut use may play a role in the development of MetS. Further study is required to establish causation and to investigate the potential benefits of substance use cessation in reducing the risk of MetS.


Assuntos
Síndrome Metabólica , Militares , Humanos , Masculino , Feminino , Adulto , Militares/estatística & dados numéricos , Síndrome Metabólica/epidemiologia , Taiwan/epidemiologia , Incidência , Adulto Jovem , Adolescente , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Fatores de Risco , Areca/efeitos adversos , Estudos de Coortes
14.
Kidney Res Clin Pract ; 43(3): 263-273, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38863384

RESUMO

With an increasing aging population, the mean age of patients with end-stage kidney disease (ESKD) is globally increasing. However, the current clinical status of elderly patients undergoing hemodialysis (HD) is rarely reported in Korea. The current study analyzed the clinical features and trends of older patients undergoing HD from the Korean Renal Data System (KORDS) database. The patients were divided into three groups according to age: <65 years (the young group), n = 50,591 (35.9%); 65-74 years (the younger-old group), n = 37,525 (26.6%); and ≥75 years (the older-old group), n = 52,856 (37.5%). The proportion of older-old group undergoing HD significantly increased in incidence and decreased in prevalence from 2013 to 2022. The median levels of hemoglobin, serum creatinine, albumin, calcium, phosphorus, and intact parathyroid hormone significantly decreased in the older-old group. The proportions of arteriovenous fistula creation and left forearm placement showed decreased trends with age. Although the utilization of low surface area dialyzers increased with age, the dialysis adequacy, including urea reduction ratio and Kt/V was within acceptable range in the older-old group on HD. Over the past 20 years, the mortality rate in the older-old group has increased, with cardiovascular diseases decreasing and infectious diseases increasing. The incidence of elderly patients undergoing HD has increased over time, but the high mortality of the older-old group needs to be solved. Therefore, it is imperative to develop holistic strategies based on age and individual needs for patients with ESKD.

15.
Diabetologia ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879617

RESUMO

AIMS/HYPOTHESIS: Glomerular lipid accumulation is a defining feature of diabetic kidney disease (DKD); however, the precise underlying mechanism requires further elucidation. Recent evidence suggests a role for proprotein convertase subtilisin/kexin type 9 (PCSK9) in intracellular lipid homeostasis. Although PCSK9 is present in kidneys, its role within kidney cells and relevance to renal diseases remain largely unexplored. Therefore, we investigated the role of intracellular PCSK9 in regulating lipid accumulation and homeostasis in the glomeruli and podocytes under diabetic conditions. Furthermore, we aimed to identify the pathophysiological mechanisms responsible for the podocyte injury that is associated with intracellular PCSK9-induced lipid accumulation in DKD. METHODS: In this study, glomeruli were isolated from human kidney biopsy tissues, and glomerular gene-expression analysis was performed. Also, db/db and db/m mice were used to perform glomerular gene-expression profiling. We generated DKD models using a high-fat diet and low-dose intraperitoneal streptozocin injection in C57BL/6 and Pcsk9 knockout (KO) mice. We analysed cholesterol and triacylglycerol levels within the kidney cortex. Lipid droplets were evaluated using BODIPY staining. We induced upregulation and downregulation of PCSK9 expression in conditionally immortalised mouse podocytes using lentivirus and siRNA transfection techniques, respectively, under diabetic conditions. RESULTS: A significant reduction in transcription level of PCSK9 was observed in glomeruli of individuals with DKD. PCSK9 expression was also reduced in podocytes of animals under diabetic conditions. We observed significantly higher lipid accumulation in kidney tissues of Pcsk9 KO DKD mice compared with wild-type (WT) DKD mice. Additionally, Pcsk9 KO mouse models of DKD exhibited a significant reduction in mitochondria number vs WT models, coupled with a significant increase in mitochondrial size. Moreover, albuminuria and podocyte foot process effacement were observed in WT and Pcsk9 KO DKD mice, with KO DKD mice displaying more pronounced manifestations. Immortalised mouse podocytes exposed to diabetic stimuli exhibited heightened intracellular lipid accumulation, mitochondrial injury and apoptosis, which were ameliorated by Pcsk9 overexpression and aggravated by Pcsk9 knockdown in mouse podocytes. CONCLUSIONS/INTERPRETATION: The downregulation of PCSK9 in podocytes is associated with lipid accumulation, which leads to mitochondrial dysfunction, cell apoptosis and renal injury. This study sheds new light on the potential involvement of PCSK9 in the pathophysiology of glomerular lipid accumulation and podocyte injury in DKD.

16.
Appl Microbiol Biotechnol ; 108(1): 323, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713233

RESUMO

Ergot alkaloids (EAs) are a diverse group of indole alkaloids known for their complex structures, significant pharmacological effects, and toxicity to plants. The biosynthesis of these compounds begins with chanoclavine-I aldehyde (CC aldehyde, 2), an important intermediate produced by the enzyme EasDaf or its counterpart FgaDH from chanoclavine-I (CC, 1). However, how CC aldehyde 2 is converted to chanoclavine-I acid (CC acid, 3), first isolated from Ipomoea violacea several decades ago, is still unclear. In this study, we provide in vitro biochemical evidence showing that EasDaf not only converts CC 1 to CC aldehyde 2 but also directly transforms CC 1 into CC acid 3 through two sequential oxidations. Molecular docking and site-directed mutagenesis experiments confirmed the crucial role of two amino acids, Y166 and S153, within the active site, which suggests that Y166 acts as a general base for hydride transfer, while S153 facilitates proton transfer, thereby increasing the acidity of the reaction. KEY POINTS: • EAs possess complicated skeletons and are widely used in several clinical diseases • EasDaf belongs to the short-chain dehydrogenases/reductases (SDRs) and converted CC or CC aldehyde to CC acid • The catalytic mechanism of EasDaf for dehydrogenation was analyzed by molecular docking and site mutations.


Assuntos
Aldeídos , Alcaloides de Claviceps , Aldeídos/metabolismo , Aldeídos/química , Domínio Catalítico , Alcaloides de Claviceps/biossíntese , Alcaloides de Claviceps/química , Alcaloides de Claviceps/metabolismo , Simulação de Acoplamento Molecular , Mutagênese Sítio-Dirigida , Oxirredução , Oxirredutases/metabolismo , Oxirredutases/genética , Oxirredutases/química
17.
Microb Cell Fact ; 23(1): 134, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724934

RESUMO

BACKGROUND: Lovastatin has widespread applications thanks to its multiple pharmacological effects. Fermentation by filamentous fungi represents the major way of lovastatin production. However, the current lovastatin productivity by fungal fermentation is limited and needs to be improved. RESULTS: In this study, the lovastatin-producing strains of Aspergillus terreus from marine environment were screened, and their lovastatin productions were further improved by genetic engineering. Five strains of A. terreus were isolated from various marine environments. Their secondary metabolites were profiled by metabolomics analysis using Ultra Performance Liquid Chromatography-Mass spectrometry (UPLC-MS) with Global Natural Products Social Molecular Networking (GNPS), revealing that the production of secondary metabolites was variable among different strains. Remarkably, the strain of A. terreus MJ106 could principally biosynthesize the target drug lovastatin, which was confirmed by High Performance Liquid Chromatography (HPLC) and gene expression analysis. By one-factor experiment, lactose was found to be the best carbon source for A. terreus MJ106 to produce lovastatin. To improve the lovastatin titer in A. terreus MJ106, genetic engineering was applied to this strain. Firstly, a series of strong promoters was identified by transcriptomic and green fluorescent protein reporter analysis. Then, three selected strong promoters were used to overexpress the transcription factor gene lovE encoding the major transactivator for lov gene cluster expression. The results revealed that compared to A. terreus MJ106, all lovE over-expression mutants exhibited significantly more production of lovastatin and higher gene expression. One of them, LovE-b19, showed the highest lovastatin productivity at a titer of 1512 mg/L, which represents the highest production level reported in A. terreus. CONCLUSION: Our data suggested that combination of strain screen and genetic engineering represents a powerful tool for improving the productivity of fungal secondary metabolites, which could be adopted for large-scale production of lovastatin in marine-derived A. terreus.


Assuntos
Aspergillus , Fermentação , Engenharia Genética , Lovastatina , Lovastatina/biossíntese , Lovastatina/metabolismo , Aspergillus/metabolismo , Aspergillus/genética , Organismos Aquáticos/metabolismo , Organismos Aquáticos/genética
18.
Cell Rep ; 43(6): 114272, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795348

RESUMO

Lysine deacetylase inhibitors (KDACis) are approved drugs for cutaneous T cell lymphoma (CTCL), peripheral T cell lymphoma (PTCL), and multiple myeloma, but many aspects of their cellular mechanism of action (MoA) and substantial toxicity are not well understood. To shed more light on how KDACis elicit cellular responses, we systematically measured dose-dependent changes in acetylation, phosphorylation, and protein expression in response to 21 clinical and pre-clinical KDACis. The resulting 862,000 dose-response curves revealed, for instance, limited cellular specificity of histone deacetylase (HDAC) 1, 2, 3, and 6 inhibitors; strong cross-talk between acetylation and phosphorylation pathways; localization of most drug-responsive acetylation sites to intrinsically disordered regions (IDRs); an underappreciated role of acetylation in protein structure; and a shift in EP300 protein abundance between the cytoplasm and the nucleus. This comprehensive dataset serves as a resource for the investigation of the molecular mechanisms underlying KDACi action in cells and can be interactively explored online in ProteomicsDB.


Assuntos
Inibidores de Histona Desacetilases , Proteômica , Humanos , Inibidores de Histona Desacetilases/farmacologia , Proteômica/métodos , Acetilação/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Lisina/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Proteína p300 Associada a E1A/metabolismo , Histona Desacetilases/metabolismo
19.
Biomolecules ; 14(5)2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38785979

RESUMO

The balance between ubiquitination and deubiquitination is instrumental in the regulation of protein stability and maintenance of cellular homeostasis. The deubiquitinating enzyme, ubiquitin-specific protease 36 (USP36), a member of the USP family, plays a crucial role in this dynamic equilibrium by hydrolyzing and removing ubiquitin chains from target proteins and facilitating their proteasome-dependent degradation. The multifaceted functions of USP36 have been implicated in various disease processes, including cancer, infections, and inflammation, via the modulation of numerous cellular events, including gene transcription regulation, cell cycle regulation, immune responses, signal transduction, tumor growth, and inflammatory processes. The objective of this review is to provide a comprehensive summary of the current state of research on the roles of USP36 in different pathological conditions. By synthesizing the findings from previous studies, we have aimed to increase our understanding of the mechanisms underlying these diseases and identify potential therapeutic targets for their treatment.


Assuntos
Neoplasias , Ubiquitina Tiolesterase , Humanos , Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/enzimologia , Neoplasias/patologia , Ubiquitina Tiolesterase/metabolismo , Ubiquitina Tiolesterase/genética , Animais , Ubiquitinação , Inflamação/metabolismo , Transdução de Sinais , Ubiquitina/metabolismo
20.
J Tradit Complement Med ; 14(3): 266-275, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38707917

RESUMO

Mulberry leaf has been recognized as a traditional Chinese medicinal plant, which was distributed throughout the Asia. The aqueous extract of mulberry leaf extract (MLE) has various biologically active components such as polyphenols and flavonoids. However, the inhibitory effect of MLE in hepatocarcinogenesis is poorly understood. In this study, we determined the role of MLE supplementation in preventing hepatocarcinogenesis in a carcinogen-initiated high-fat diet (HFD)-promoted Sprague-Dawley (SD) rat model. The rats were fed an HFD to induce obesity and spontaneous hepatomas by administering 0.01% diethylnitrosamine (DEN) in their drinking water for 12 weeks (HD group), and also to fed MLE through oral ingestion at daily doses of 0.5%, 1%, or 2%. At the end of the 12-week experimental period, the liver tumors were analyzed to identify markers of oxidative stress and antioxidant enzyme activities, and their serum was analyzed to determine their nutritional status and liver function. Histopathological analysis revealed that MLE supplementation significantly suppressed the severity and incidence of hepatic tumors. Furthermore, compared with the HFD + DEN groups, the expression of protein kinase C (PKC)-α and Rac family small GTPase 1 (Rac1) was lower in the MLE groups. These findings suggest that MLE prevents obesity-enhanced, carcinogen-induced hepatocellular carcinoma development, potentially through the protein kinase C (PKC)α/Rac1 signaling pathway. MLE might be an effective chemoprevention modality for nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH)-related hepatocarcinogenesis.

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