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1.
Subcell Biochem ; 104: 383-408, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38963493

RESUMO

Oxidoreductases facilitating electron transfer between molecules are pivotal in metabolic pathways. Flavin-based electron bifurcation (FBEB), a recently discovered energy coupling mechanism in oxidoreductases, enables the reversible division of electron pairs into two acceptors, bridging exergonic and otherwise unfeasible endergonic reactions. This chapter explores the four distinct FBEB complex families and highlights a decade of structural insights into FBEB complexes. In this chapter, we discuss the architecture, electron transfer routes, and conformational changes across all FBEB families, revealing the structural foundation that facilitate these remarkable functions.


Assuntos
Flavinas , Transporte de Elétrons , Flavinas/metabolismo , Flavinas/química , Oxirredutases/metabolismo , Oxirredutases/química , Conformação Proteica , Modelos Moleculares , Oxirredução
2.
Nanomaterials (Basel) ; 14(13)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38998680

RESUMO

With the rapid growth of the economy, people are increasingly reliant on energy sources. However, in recent years, the energy crisis has gradually intensified. As a clean energy source, methane has garnered widespread attention for its development and utilization. This study employed both large-scale computational screening and machine learning to investigate the adsorption and diffusion properties of thousands of metal-organic frameworks (MOFs) in six gas binary mixtures of CH4 (H2/CH4, N2/CH4, O2/CH4, CO2/CH4, H2S/CH4, He/CH4) for methane purification. Firstly, a univariate analysis was conducted to discuss the relationships between the performance indicators of adsorbents and their characteristic descriptors. Subsequently, four machine learning methods were utilized to predict the diffusivity/selectivity of gas, with the light gradient boosting machine (LGBM) algorithm emerging as the optimal one, yielding R2 values of 0.954 for the diffusivity and 0.931 for the selectivity. Furthermore, the LGBM algorithm was combined with the SHapley Additive exPlanation (SHAP) technique to quantitatively analyze the relative importance of each MOF descriptor, revealing that the pore limiting diameter (PLD) was the most critical structural descriptor affecting molecular diffusivity. Finally, for each system of CH4 mixture, three high-performance MOFs were identified, and the commonalities among high-performance MOFs were analyzed, leading to the proposals of three design principles involving changes only to the metal centers, organic linkers, or topological structures. Thus, this work reveals microscopic insights into the separation mechanisms of CH4 from different binary mixtures in MOFs.

3.
Res Sq ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38978573

RESUMO

Background: The Diabetes Telemedicine Mediterranean Diet (DiaTeleMed) Study is a fully remote randomized clinical trial evaluating personalized dietary management in individuals with type 2 diabetes (T2D). The study aims to test the efficacy of a personalized behavioral approach for dietary management of moderately-controlled T2D, versus a standardized behavioral intervention that uses one-size-fits-all dietary recommendations, versus a usual care control (UCC). The primary outcome will compare the impact of each intervention on the mean amplitude of glycemic excursions (MAGE). Methods: Eligible participants are between 21 to 80 years of age diagnosed with moderately-controlled T2D (HbA1c: 6.0-8.0%), and managed on lifestyle alone or lifestyle plus metformin. Participants must be willing and able to attend virtual counseling sessions and log meals into a dietary tracking smartphone application (DayTwo), and wear a continuous glucose monitor (CGM) for up to 12 days. Participants are randomized with equal allocation (n = 255, n = 85 per arm) to one of three arms: 1) Personalized, 2) Standardized, or 3) UCC. Measurements occur at 0 (baseline), 3, and 6 months. All participants receive isocaloric energy and macronutrients targets to meet Mediterranean diet guidelines plus 14 intervention contacts over 6 months (4 weekly then 10 biweekly) to cover diabetes self-management education. The first 4 UCC intervention contacts are delivered via synchronous videoconferences followed by educational video links. Participants in Standardized receive the same education content as UCC on the same schedule. However, all intervention contacts are conducted via synchronous videoconferences, paired with Social Cognitive Theory (SCT)-based behavioral counseling, plus dietary self-monitoring of planned meals using a mobile app that provides real-time feedback on calories and macronutrients. Participants in the Personalized arm receive all elements of the Standardized intervention, plus real-time feedback on predicted post-prandial glycemic response (PPGR) to meals and snacks logged into the mobile app. Discussion: The DiaTeleMed study will address an important gap in the current landscape of precision nutrition by determining the contributions of behavioral counseling and personalized nutrition recommendations on glycemic control in individuals with T2D. The fully remote methodology of the study allows for scalability and innovative delivery of personalized dietary recommendations at a population level. Trial registration: The DiaTeleMed Study is registered with ClinicalTrials.gov (Identifier: NCT05046886).

4.
Food Chem X ; 23: 101548, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38974200

RESUMO

Granaticins are natural pigments derived from microorganisms with promising bioactivity. However, their practical applications have been restricted due to inherent instability. To improve the stability of granaticins from the novel strain Streptomyces vilmorinianum YP1, microcapsules were prepared using gum Arabic (GA) by a freeze-drying method. The optimal parameters for microencapsulation were determined using response surface methodology. Under the optimal conditions (GA 9.2% (v/v), a wall/-core ratio 4.8 (w/w), encapsulating temperature 29 °C), the maximum encapsulation efficiency achieved was 93.64%. The microcapsules were irregular single crystals with an average particle size of 206.37 ± 2.51 nm. Stability testing indicated improved stability of the microencapsulated granaticins. Notably, granaticnic B retention increased by 17.0% and 6.6% after exposure to sunlight and storage at 4 °C, respectively. These finding suggest that GA as a well material significantly enhances the stability of granaticins from S. vilmorinianum YP1, facilitating their potential applications.

5.
Org Lett ; 26(24): 5146-5150, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38857062

RESUMO

We report herein the total syntheses of three marsupellin-family sesquiterpenoids, (±)-acetoxymarsupellone and (±)-marsupellins B and D, in 14-19 steps from our known precursor, making marsupellin A also accessible from marsupellin B through a known procedure. The critical tricyclic framework bearing the challenging C7 bridgehead all-carbon quaternary center is strategically constructed through a Ti-mediated reductive cyclization and semipinacol rearrangement sequence. This study provides a general approach to the syntheses of (ent-)longipinane-type molecules.

6.
Kidney Int Rep ; 9(6): 1836-1848, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38899198

RESUMO

Introduction: Hyperoxaluria is a risk factor for kidney stone formation and chronic kidney disease progression. The microbiome is an important protective factor against oxalate accumulation through the activity of its oxalate-degrading enzymes (ODEs). In this cross-sectional study, we leverage multiomics to characterize the microbial community of participants with primary and enteric hyperoxaluria, as well as idiopathic calcium oxalate kidney stone (CKS) formers, focusing on the relationship between oxalate degrading functions of the microbiome. Methods: Patients diagnosed with type 1 primary hyperoxaluria (PH), enteric hyperoxaluria (EH), and CKS were screened for inclusion in the study. Participants completed a food frequency questionnaire recording their dietary oxalate content while fecal oxalate levels were ascertained. DNA and RNA were extracted from stool samples and sequenced. Metagenomic (MTG) and metatranscriptomic (MTT) data were processed through our bioinformatics pipelines, and microbiome diversity, differential abundance, and networks were subject to statistical analysis in relationship with oxalate levels. Results: A total of 38 subjects were recruited, including 13 healthy participants, 12 patients with recurrent CKS, 8 with PH, and 5 with EH. Urinary and fecal oxalate were significantly higher in the PH and the EH population compared to healthy controls. At the community level, alpha-diversity and beta-diversity indices were similar across all populations. The respective contributions of single bacterial species to the total oxalate degradative potential were similar in healthy and PH subjects. MTT-based network analysis identified the most interactive bacterial network in patients with PH. Patients with EH had a decreased abundance of multiple major oxalate degraders. Conclusion: The composition and inferred activity of oxalate-degrading microbiota were differentially associated with host clinical conditions. Identifying these changes improves our understanding of the relationships between dietary constituents, microbiota, and oxalate homeostasis, and suggests new therapeutic approaches protecting against hyperoxaluria.

7.
Nat Struct Mol Biol ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871854

RESUMO

Humans have three different proliferating cell nuclear antigen (PCNA) clamp-loading complexes: RFC and CTF18-RFC load PCNA onto DNA, but ATAD5-RFC can only unload PCNA from DNA. The underlying structural basis of ATAD5-RFC unloading is unknown. We show here that ATAD5 has two unique locking loops that appear to tie the complex into a rigid structure, and together with a domain that plugs the DNA-binding chamber, prevent conformation changes required for DNA binding, likely explaining why ATAD5-RFC is exclusively a PCNA unloader. These features are conserved in the yeast PCNA unloader Elg1-RFC. We observe intermediates in which PCNA bound to ATAD5-RFC exists as a closed planar ring, a cracked spiral or a gapped spiral. Surprisingly, ATAD5-RFC can open a PCNA gap between PCNA protomers 2 and 3, different from the PCNA protomers 1 and 3 gap observed in all previously characterized clamp loaders.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38822923

RESUMO

Prostate-specific antigen (PSA)-based prostate cancer screening is a preference-sensitive decision for which experts recommend a shared decision making (SDM) approach. This study aimed to examine PSA screening SDM in primary care. Methods included qualitative analysis of audio-recorded patient-provider interactions supplemented by quantitative description. Participants included 5 clinic providers and 13 patients who were: (1) 40-69 years old, (2) Black, (3) male, and (4) attending clinic for routine primary care. Main measures were SDM element themes and "observing patient involvement in decision making" (OPTION) scoring. Some discussions addressed advantages, disadvantages, and/or scientific uncertainty of screening, however, few patients received all SDM elements. Nearly all providers recommended screening, however, only 3 patients were directly asked about screening preferences. Few patients were asked about prostate cancer knowledge (2), urological symptoms (3), or family history (6). Most providers discussed disadvantages (80%) and advantages (80%) of PSA screening. Average OPTION score was 25/100 (range 0-67) per provider. Our study found limited SDM during PSA screening consultations. The counseling that did take place utilized components of SDM but inconsistently and incompletely. We must improve SDM for PSA screening for diverse patient populations to promote health equity. This study highlights the need to improve SDM for PSA screening.

9.
Int Immunopharmacol ; 137: 112491, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38909499

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common and complex endocrine disease in women, with a prevalence of 5% to 18% worldwide. HeQi San (HQS) is a Chinese medicine compound prescription, which has been applied to treat various endocrine and metabolic diseases. OBJECTIVE: The study was intended to investigate the effect of HQS on PCOS, and clarify the potential mechanism via in vivo and in vitro experiments. METHODS: The PCOS mouse model was established by injecting the dehydroepiandrosterone (DHEA) subcutaneously and fading high-fat diet for 3 weeks. After making model, PCOS mice were treated with HQS (8.75 g/kg and 17.5 g/kg, ig.) for 4 weeks. Firstly, we assessed the histopathological changes in ovary tissues and detected the hormone level. Subsequently, the study evaluated the capability of anti-inflammatory and regulating macrophage polarization of HQS in vivo and in vitro. The secretion of inflammation indicators was measured with Elisa kits, and the expression level of phosphorylated nuclear factor kappa-B (P-NFκB) and B-lymphocyte activation antigen B7 (CD80) was measured by immunofluorescence and Western blot. Meanwhile, the apoptosis of ovarian granulosa cells was detected via tunel staining and Western blot. The co-culture model in vitro was utilized to assess the effect between macrophage polarization and human ovarian granulosa cells (KGN cells) apoptosis. Furthermore, 16S rDNA sequencing was utilized to elevate gut microbiota change in PCOS mice. RESULTS: HQS reversed the abnormal hormone increase, ameliorated insulin resistance, and improved histopathological changes of the ovary tissue to exert the therapeutic effect. HQS inhibited the expression of P-NF-κB and decreased the production of interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) to further prohibit the macrophage M1 polarization in ovary tissues and macrophages. The apoptosis-positive cells, Bcl-2 Assaciated X protein (BAX), and cleaved-caspase 3 expression were also decreased in the treatment group. The B-cell lymphoma-2 (Bcl2) expression was enhanced after HQS treatment in vivo. The co-culture experiments also verified that HQS could prevent the apoptosis of KGN cells. Furthermore, HQS mediated the abundance of gut flora. The abundance of bifldobacterium and parasutterella was increased and the abundance of lachnoclostridium was decreased. CONCLUSION: The study verified that HQS has the effect of anti-inflammation and inhibits macrophage M1 polarization. Besides, HQS could mediate the abundance of gut microbiota in mice with PCOS. Thus, this study would provide more reasonable basis of HQS for clinical use. In conclusion, HQS might be a potential candidate for PCOS treatment.


Assuntos
Anti-Inflamatórios , Desidroepiandrosterona , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas , Microbioma Gastrointestinal , Síndrome do Ovário Policístico , Animais , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/imunologia , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Ovário/patologia , Ovário/efeitos dos fármacos , Ovário/imunologia , Ovário/metabolismo , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Células RAW 264.7 , Citocinas/metabolismo , Apoptose/efeitos dos fármacos , NF-kappa B/metabolismo , Dieta Hiperlipídica/efeitos adversos , Inflamação/tratamento farmacológico , Camundongos Endogâmicos C57BL
10.
Artigo em Inglês | MEDLINE | ID: mdl-38877193

RESUMO

Dredging eutrophic lake sediments can improve water quality, but it also requires dewatering and valorizing the dredged material to avoid wasting resources like phosphorus. This study experimentally investigated the basic mechanism and performance of electroosmotic dewatering of 1-L dredged sediments using different electric currents (20 mA, 40 mA, and 60 mA) after gravity filtration. The dewatering performance, moisture content and distribution, effect of electrochemical reaction on dewaterability, energy consumption, and changes in metals and phosphorus (P) distribution and pH values were analyzed. The results indicated that electroosmotic dewatering effectively decreased sediment mass by predominantly eliminating free and a portion of interstitial water, with reductions ranging from 7 to 20%. The optimal duration and current should, however, be considered to balance water removal and energy consumption. Higher moisture removal occurred with 40 mA for 24 h and 60 mA for 6 h, while the energy consumption obtained with 60 mA (0.201 kWh/kg water removed) was significantly lower than that of applying 40 mA for 24 h (0.473 kWh/kg water removed), with the assistance of ohmic heating, resulting in reduced viscosity and water release from capillaries. The tested conditions did not significantly extract heavy metals or P from the sediments, which may facilitate the disposal of the removed water back into the lake and the utilization of the treated sediments for different purposes. This technology is easy to operate and suitable for the treatment of dredged sediments, and the dewatering result is comparable to low pressurized filtration but at low energy consumption.

11.
Nat Methods ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744918

RESUMO

The combination of native electrospray ionization with top-down fragmentation in mass spectrometry (MS) allows simultaneous determination of the stoichiometry of noncovalent complexes and identification of their component proteoforms and cofactors. Although this approach is powerful, both native MS and top-down MS are not yet well standardized, and only a limited number of laboratories regularly carry out this type of research. To address this challenge, the Consortium for Top-Down Proteomics initiated a study to develop and test protocols for native MS combined with top-down fragmentation of proteins and protein complexes across 11 instruments in nine laboratories. Here we report the summary of the outcomes to provide robust benchmarks and a valuable entry point for the scientific community.

12.
Toxicol Lett ; 397: 79-88, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38734220

RESUMO

The activation of pregnane X receptor (PXR) or peroxisome proliferator-activated receptor α (PPARα) can induce liver enlargement. Recently, we reported that PXR or PPARα activation-induced hepatomegaly depends on yes-associated protein (YAP) signaling and is characterized by hepatocyte hypertrophy around the central vein area and hepatocyte proliferation around the portal vein area. However, it remains unclear whether PXR or PPARα activation-induced hepatomegaly can be reversed after the withdrawal of their agonists. In this study, we investigated the regression of enlarged liver to normal size following the withdrawal of PCN or WY-14643 (typical agonists of mouse PXR or PPARα) in C57BL/6 mice. The immunohistochemistry analysis of CTNNB1 and KI67 showed a reversal of hepatocyte size and a decrease in hepatocyte proliferation after the withdrawal of agonists. In details, the expression of PXR or PPARα downstream proteins (CYP3A11, CYP2B10, ACOX1, and CYP4A) and the expression of proliferation-related proteins (CCNA1, CCND1, and PCNA) returned to the normal levels. Furthermore, YAP and its downstream proteins (CTGF, CYR61, and ANKRD1) also restored to the normal states, which was consistent with the change in liver size. These findings demonstrate the reversibility of PXR or PPARα activation-induced hepatomegaly and provide new data for the safety of PXR and PPARα as drug targets.


Assuntos
Proliferação de Células , Hepatócitos , Hepatomegalia , Fígado , PPAR alfa , Receptor de Pregnano X , Pirimidinas , Proteínas de Sinalização YAP , Animais , Masculino , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Hidrocarboneto de Aril Hidroxilases , beta Catenina/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Proliferação de Células/efeitos dos fármacos , Citocromo P-450 CYP3A , Citocromo P-450 CYP4A/metabolismo , Citocromo P-450 CYP4A/genética , Família 2 do Citocromo P450 , Família 4 do Citocromo P450/genética , Família 4 do Citocromo P450/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Hepatomegalia/induzido quimicamente , Hepatomegalia/metabolismo , Hepatomegalia/patologia , Antígeno Ki-67/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Proteínas de Membrana , Camundongos Endogâmicos C57BL , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , PPAR alfa/agonistas , PPAR alfa/metabolismo , Receptor de Pregnano X/metabolismo , Receptor de Pregnano X/genética , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Esteroide Hidroxilases , Proteínas de Sinalização YAP/metabolismo
13.
J Biol Chem ; 300(6): 107387, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38763336

RESUMO

The cryo-EM resolution revolution has heralded a new era in our understanding of eukaryotic lipid flippases with a rapidly growing number of high-resolution structures. Flippases belong to the P4 family of ATPases (type IV P-type ATPases) that largely follow the reaction cycle proposed for the more extensively studied cation-transporting P-type ATPases. However, unlike the canonical P-type ATPases, no flippase cargos are transported in the phosphorylation half-reaction. Instead of being released into the intracellular or extracellular milieu, lipid cargos are transported to their destination at the inner leaflet of the membrane. Recent flippase structures have revealed multiple conformational states during the lipid transport cycle. Nonetheless, critical conformational states capturing the lipid cargo "in transit" are still missing. In this review, we highlight the amazing structural advances of these lipid transporters, discuss various perspectives on catalytic and regulatory mechanisms in the literature, and shed light on future directions in further deciphering the detailed molecular mechanisms of lipid flipping.


Assuntos
Adenosina Trifosfatases , Humanos , Animais , Adenosina Trifosfatases/metabolismo , Adenosina Trifosfatases/química , Microscopia Crioeletrônica , Transporte Biológico , Proteínas de Transferência de Fosfolipídeos/metabolismo , Proteínas de Transferência de Fosfolipídeos/química , Proteínas de Transferência de Fosfolipídeos/genética , Metabolismo dos Lipídeos , Conformação Proteica
14.
Nefrologia (Engl Ed) ; 44(2): 180-193, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38697696

RESUMO

BACKGROUND: Contrast agents can directly or indirectly induce renal tubular ischemia and hypoxic damage. Given that cobalt chloride (CoCl2) can protect renal tubules, the protective effect and potential mechanism of action of CoCl2 on contrast-induced nephropathy (CIN) warrant investigation. METHODS: A CIN mouse model was established to determine the protective effect of CoCl2 on renal injury in vivo. Then, TMT-based proteomics was performed to determine the differentially expressed proteins (DEPs), following which, enrichment analyses of gene ontology and the KEGG pathway were performed. In vitro, a CIN model was constructed with renal tubular epithelial cells (HK-2) to determine the effect of CoCl2 on potential targets and the role of the key protein identified from the in vivo experiments. RESULTS: CoCl2 treatment decreased the levels of BUN and serum creatinine (sCr), while increasing the levels of urea and creatinine (Cr) in the urine of mice after CIN injury. Damage to the renal tubules in the CoCl2 treatment group was significantly less than in the CIN model group. We identified 79 DEPs after treating the in vivo model with CoCl2, and frequently observed ferroptosis-related GO and KEGG pathway terms. Of these, Hp (haptoglobin) was selected and found to have a strong renoprotective effect, even though its expression level in kidney tissue decreased after CoCl2 treatment. In HK-2 cells, overexpression of Hp reduced the ferroptosis caused by erastin, while knocking down Hp negated the attenuation effect of CoCl2 on HK-2 cell ferroptosis. CONCLUSION: CoCl2 attenuated kidney damage in the CIN model, and this effect was associated with the decrease in ferroptosis mediated by Hp.


Assuntos
Cobalto , Meios de Contraste , Ferroptose , Ferroptose/efeitos dos fármacos , Animais , Camundongos , Meios de Contraste/efeitos adversos , Masculino , Nefropatias/induzido quimicamente , Nefropatias/prevenção & controle , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Humanos , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/patologia
15.
J Colloid Interface Sci ; 669: 117-125, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38705111

RESUMO

Lithium cobalt phosphate (LiCoPO4) has great potential to be developed as a cathode material for lithium-ion batteries (LIBs) due to its structural stability and higher voltage platform with a high theoretical energy density. However, the relatively low diffusion of lithium ions still needs to be improved. In this work, Fe and Zn co-doped LiCoPO4: LiCo0.9-xFe0.1ZnxPO4/C is utilized to enhance the battery performance of LiCoPO4. The electrochemical properties of LiCo0.85Fe0.1Zn0.05PO4/C demonstrated an initial capacity of 118 mAh/g, with 93.4 % capacity retention at 1C after 100 cycles, and a good capacity of 87 mAh/g remained under a high current density of 10C. In addition, the diffusion rate of Li ions was investigated, proving the improvement of the materials with doping. The impedance results also showed a smaller resistance of the doped materials. Furthermore, operando X-ray diffraction displayed a good reversibility of the structural transformation, corresponding to cycling stability. This work provided studies of both the electrochemical properties and structural transformation of Fe and Zn co-doped LiCoPO4, which showed that 10 % Fe and 5 % Zn co-doping enhanced the electrochemical performance of LiCoPO4 as a cathode material in LIBs.

16.
J Investig Med ; : 10815589241257214, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38785311

RESUMO

To explore the causal relationship between obesity and hypothyroidism, and identify risk factors and the predictive value of subclinical hypothyroidism (SCH) in obese patients using Mendelian randomization. This study employed five Mendelian randomization methods (MR Egger, Weighted Median, Inverse Variance Weighted, Simple Mode, and Weighted Mode) to analyze clinical data from 308 obese patients at the People's Hospital of Xinjiang Uygur Autonomous Region, from January 2015 to June 2023. Patients were divided based on thyroid function tests into normal (n=173) and SCH groups (n=56). Comparative analyses, along with univariate and multivariate logistic regression, were conducted to identify risk factors for SCH in obese patients. A significant association between obesity and hypothyroidism was established, especially highlighted by the Inverse Variance Weighted method. SCH patients showed higher ages, TSH levels, and thyroid autoantibody positivity rates, with lower T4 and FT4 levels. Age, FT4, thyroid autoantibodies, TPO-Ab, and Tg-Ab were confirmed as risk factors. The predictive value of FT4 levels for SCH in obesity was significant, with an AUC of 0.632. The study supports a potential causal link between obesity and hypothyroidism, identifying specific risk factors for SCH in obese patients. FT4 level stands out as an independent predictive factor, suggesting its utility in early diagnosis and preventive strategies for SCH.

17.
FEBS J ; 291(9): 1889-1891, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38581152

RESUMO

Several recent cryo-electron microscopy (cryo-EM) studies about the eukaryotic primosome, including the human primosome described by Yin et al. in this issue, have uncovered the structural intricacies between the RNA primase and the DNA polymerase. These studies show that these two partners tango on DNA to synthesize a hybrid primer composed of ~ 10 nucleotide (nt) RNA and ~ 10-nt DNA. They reveal key intermediate steps involved in this process; from the self-inhibited apo state to the initiation of RNA primer synthesis, RNA primer handover to the polymerase, primer elongation by polymerase, and finally, primer termination and release. Remarkably, the polymerase domain orchestrates all major steps during primer synthesis.


Assuntos
DNA Polimerase I , DNA , RNA , Humanos , Microscopia Crioeletrônica , DNA/química , DNA/metabolismo , DNA/genética , DNA Polimerase I/metabolismo , DNA Polimerase I/química , DNA Primase/metabolismo , DNA Primase/química , DNA Primase/genética , Primers do DNA/genética , Replicação do DNA , RNA/química , RNA/metabolismo , RNA/genética
18.
Stem Cells Dev ; 33(11-12): 321-331, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38613816

RESUMO

Human pluripotent stem cell (hPSC)-derived red blood cells (RBCs) possess great potential for compensating shortages in transfusion medicine. For better RBC generation from hPSCs, we compared the cell seeding density in the embryoid body formation-based hPSC induction protocol. In the selection of low- and high-density inoculation conditions, we found that low-density culture performed better in the final RBC product with more cell output and increased average cellular hemoglobin content. An elaborate study using flow cytometry demonstrated that low inoculation density promoted endothelial-to-hematopoietic transition, followed by improved hematopoietic progenitor formation and erythrocyte generation. The improved transformation from glycolysis to mitochondrial oxidation and reduced apoptosis might be responsible for this effect. Hints from RNA sequencing suggested that molecules involved in microenvironment interaction and metabolic regulation might respond for the different developmental potential. The possible mediators between outer message and intracellular response could be the nutrition sensors FOXO, PRKAA1 (AMPK), and MTOR genes. It is possible that low inoculation density triggered metabolic regulation signals, promoted mitochondrial oxidation, and resulted in enhanced cell amplification and hematopoietic differentiation. The low cell culture density will improve RBC generation from hPSCs.


Assuntos
Diferenciação Celular , Eritrócitos , Células-Tronco Pluripotentes , Humanos , Eritrócitos/citologia , Eritrócitos/metabolismo , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Contagem de Células , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Mitocôndrias/metabolismo
19.
Nefrología (Madrid) ; 44(2): 180-193, Mar-Abr. 2024. ilus, graf
Artigo em Inglês | IBECS | ID: ibc-231568

RESUMO

Background: Contrast agents can directly or indirectly induce renal tubular ischemia and hypoxic damage. Given that cobalt chloride (CoCl2) can protect renal tubules, the protective effect and potential mechanism of action of CoCl2 on contrast-induced nephropathy (CIN) warrant investigation. Methods: A CIN mouse model was established to determine the protective effect of CoCl2 on renal injury in vivo. Then, TMT-based proteomics was performed to determine the differentially expressed proteins (DEPs), following which, enrichment analyses of gene ontology and the KEGG pathway were performed. In vitro, a CIN model was constructed with renal tubular epithelial cells (HK-2) to determine the effect of CoCl2 on potential targets and the role of the key protein identified from the in vivo experiments. Results: CoCl2 treatment decreased the levels of BUN and serum creatinine (sCr), while increasing the levels of urea and creatinine (Cr) in the urine of mice after CIN injury. Damage to the renal tubules in the CoCl2 treatment group was significantly less than in the CIN model group. We identified 79 DEPs after treating the in vivo model with CoCl2, and frequently observed ferroptosis-related GO and KEGG pathway terms. Of these, Hp (haptoglobin) was selected and found to have a strong renoprotective effect, even though its expression level in kidney tissue decreased after CoCl2 treatment. In HK-2 cells, overexpression of Hp reduced the ferroptosis caused by erastin, while knocking down Hp negated the attenuation effect of CoCl2 on HK-2 cell ferroptosis. Conclusion: CoCl2 attenuated kidney damage in the CIN model, and this effect was associated with the decrease in ferroptosis mediated by Hp.(AU)


Antecedentes: Los agentes de contraste pueden inducir isquemia tubular renal y daño hipóxico de manera directa o indirecta. Dado que el cloruro de cobalto (CoCl2) puede proteger los túbulos renales, el efecto protector y el mecanismo de acción potencial de CoCl2 en la nefropatía inducida por contraste (NIC) merecen ser investigados. Métodos: Se estableció un modelo de NIC en ratones para determinar el efecto protector de CoCl2 en la nefropatía in vivo. Seguidamente, se realizó un análisis proteómico por TMT para determinar las proteínas diferencialmente expresadas (DEP) y, a continuación, un análisis de enriquecimiento de ontología genética y vía KEGG. In vitro, se construyó un modelo NIC en células epiteliales de túbulos renales (HK-2) para determinar el efecto de CoCl2 en los objetivos potenciales y el rol de la proteína clave identificada en los experimentos in vivo. Resultados: El tratamiento con CoCl2 redujo los niveles de BUN y de creatinina sérica e incrementó, a la vez, los de urea y creatinina en la orina de los ratones, tras la lesión NIC. El daño a los túbulos renales en el grupo de tratamiento con CoCl2 fue significativamente menor que en el grupo de modelo NIC. Identificamos 79 DEP tras el tratamiento en el modelo in vivo con CoCl2 y observamos con frecuencia ontología genética relacionada con ferroptosis y términos de vías KEGG. De ellos, se seleccionó la haptoglobina (Hp) y se encontró que tenía un fuerte efecto renoprotector, aun cuando su nivel de expresión en el tejido renal se redujo tras el tratamiento con CoCl2. En las células HK-2, la sobreexpresión de Hp redujo la ferroptosis causada por erastina, a pesar de que el descenso de Hp negó el efecto atenuador de CoCl2 en la ferroptosis de las células HK-2. Conclusión: El CoCl2 atenuó el daño renal en el modelo NIC y se asoció este efecto al descenso de ferroptosis mediada por Hp.(AU)


Assuntos
Animais , Ratos , Nefropatias , Nefropatias/induzido quimicamente , Nefrologia
20.
Front Endocrinol (Lausanne) ; 15: 1358311, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606083

RESUMO

Background: Increasing evidence indicates that immune response underlies the pathology of type 2 diabetes (T2D). Nevertheless, the specific inflammatory regulators involved in this pathogenesis remain unclear. Methods: We systematically explored circulating inflammatory proteins that are causally associated with T2D via a bidirectional Mendelian randomization (MR) study and further investigated them in prevalent complications of T2D. Genetic instruments for 91 circulating inflammatory proteins were derived from a genome-wide association study (GWAS) that enrolled 14,824 predominantly European participants. Regarding the summary-level GWASs of type 2 diabetes, we adopted the largest meta-analysis of European population (74,124 cases vs. 824,006 controls) and a prospective nested case-cohort study in Europe (9,978 cases vs. 12,348 controls). Summary statistics for five complications of T2D were acquired from the FinnGen R9 repository. The inverse variance-weighted method was applied as the primary method for causal inference. MR-Egger, weighted median and maximum likelihood methods were employed as supplementary analyses. Results from the two T2D studies were combined in a meta-analysis. Sensitivity analyses and phenotype-wide association studies (PheWAS) were performed to detect heterogeneity and potential horizontal pleiotropy in the study. Results: Genetic evidence indicated that elevated levels of TGF-α (OR = 1.16, 95% CI = 1.15-1.17) and CX3CL1 (OR = 1.30, 95% CI = 1.04-1.63) promoted the occurrence of T2D, and increased concentrations of FGF-21 (OR = 0.87, 95% CI = 0.81-0.93) and hGDNF (OR = 0.96, 95% CI = 0.95-0.98) mitigated the risk of developing T2D, while type 2 diabetes did not exert a significant influence on said proteins. Elevated levels of TGF-α were associated with an increased risk of ketoacidosis, neurological complications, and ocular complications in patients with T2D, and increased concentrations of FGF-21 were potentially correlated with a diminished risk of T2D with neurological complications. Higher levels of hGDNF were associated with an increased risk of T2D with peripheral vascular complications, while CX3CL1 did not demonstrate a significant association with T2D complications. Sensitivity analyses and PheWAS further ensure the robustness of our findings. Conclusion: This study determined four circulating inflammatory proteins that affected the occurrence of T2D, providing opportunities for the early prevention and innovative therapy of type 2 diabetes and its complications.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Estudos de Coortes , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Estudos Prospectivos , Fator de Crescimento Transformador alfa
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