Roles of Pyruvate, NADH, and Mitochondrial Complex I in Redox Balance and Imbalance in β

Pancreatic β cells not only use glucose as an energy source, but also sense blood glucose levels for insulin secretion. While pyruvate and NADH metabolic pathways are known to be involved in regulating insulin secretion in response to glucose stimulation, the roles of many other components along the metabolic pathways remain poorly understood. Such is the case for mitochondrial complex I (NADH/ubiquinone oxidoreductase). It is known that normal complex I function is absolutely required for episodic insulin secretion after a meal, but the role of complex I in β cells in the diabetic pancreas remains to be investigated. In this paper, we review the roles of pyruvate, NADH, and complex I in insulin secretion and hypothesize that complex I plays a crucial role in the pathogenesis of β cell dysfunction in the diabetic pancreas. This hypothesis is based on the establishment that chronic hyperglycemia overloads complex I with NADH leading to enhanced complex I production of reactive oxygen species. As nearly all metabolic pathways are impaired in diabetes, understanding how complex I in the β cells copes with elevated levels of NADH in the diabetic pancreas may provide potential therapeutic strategies for diabetes

Epitaxial Single-Domain Cu-BTC Metal-Organic Framework Thin Films and Foils by Electrochemical Conversion of Cuprous Oxide

Metal-Organic Frameworks (MOFs) Are an Important Class of Crystalline Porous Materials with Extensive Chemical and Structural Merits. However, the Fabrication of MOF Thin Films Oriented Along All Crystallographic Axes to Achieve Well-Aligned Nanopores and Nanochannels with Uniform Apertures Remains a Challenge. Here, We Achieved Highly Crystalline Single-Domain MOF Thin Films with the [111] Out-Of-Plane Orientation by Electrochemical Conversion of Cuprous Oxide. Copper(II)-Benzene-1,3,5-Tricarboxylate, Cu3(BTC)2 (Referred to as Cu-BTC), is a Well-Known Metal-Organic Open Framework Material with a Cubic Crystal System. Epitaxial Cu-BTC(111) Thin Films Were Manufactured by Electrochemical Oxidation of Cu2O(111) Films Electrodeposited on Single-Crystal Au(111). the Cu-BTC(111) Shows an In-Plane Antiparallel Relationship with the Precursor Cu2O(111) with a −0.91% Coincidence Site Lattice Mismatch. a Plausible Mechanism Was Proposed for the Electrochemical Conversion of Cu2O into Cu-BTC, Indicating Formation of Intermediate CuO, Growth of Cu-BTC Islands, and Termination with Coalesce into a Dense Film with a Limiting Thickness of About 740 Nm. the Faradaic Efficiency for the Electrochemical Conversion Was 63%. in Addition, Epitaxial Cu-BTC(111) Foils Were Fabricated by Epitaxial Lift-Off Following the Electrochemical Etching of Residual Cu2O Underneath the Cu-BTC. It Was Also Demonstrated that Cu-BTC(111) Films with Two In-Plane Domains and Textured Cu-BTC(111) Films Can Be Achieved on a Large Scale using Electrodeposited Au/Si and Au-Coated Glass as Low-Cost Substrates

Capn2 Correlates With insulin Resistance States in Pcos as Evidenced By Multi-Dataset analysis

OBJECTIVE: IR emerges as a feature in the pathophysiology of PCOS, precipitating ovulatory anomalies and endometrial dysfunctions that contribute to the infertility challenges characteristic of this condition. Despite its clinical significance, a consensus on the precise mechanisms by which IR exacerbates PCOS is still lacking. This study aims to harness bioinformatics tools to unearth key IR-associated genes in PCOS patients, providing a platform for future therapeutic research and potential intervention strategies. METHODS: We retrieved 4 datasets detailing PCOS from the GEO, and sourced IRGs from the MSigDB. We applied WGCNA to identify gene modules linked to insulin resistance, utilizing IR scores as a phenotypic marker. Gene refinement was executed through the LASSO, SVM, and Boruta feature selection algorithms. qPCR was carried out on selected samples to confirm findings. We predicted both miRNA and lncRNA targets using the ENCORI database, which facilitated the construction of a ceRNA network. Lastly, a drug-target network was derived from the CTD. RESULTS: Thirteen genes related to insulin resistance in PCOS were identified via WGCNA analysis. LASSO, SVM, and Boruta algorithms further isolated CAPN2 as a notably upregulated gene, corroborated by biological verification. The ceRNA network involving lncRNA XIST and hsa-miR-433-3p indicated a possible regulatory link with CAPN2, supported by ENCORI database. Drug prediction analysis uncovered seven pharmacological agents, most being significant regulators of the endocrine system, as potential candidates for addressing insulin resistance in PCOS. CONCLUSIONS: This study highlights the pivotal role of CAPN2 in insulin resistance within the context of PCOS, emphasizing its importance as both a critical biomarker and a potential therapeutic target. By identifying CAPN2, our research contributes to the expanding evidence surrounding the CAPN family, particularly CAPN10, in insulin resistance studies beyond PCOS. This work enriches our understanding of the mechanisms underlying insulin resistance, offering insights that bridge gaps in the current scientific landscape

Compositionally tuned NixSn alloys as anode materials for lithium-ion and sodium-ion batteries with a high pseudocapacitive contribution

Nickel tin alloy nanoparticles (NPs) with tuned composition NixSn (0.6 ≤ x ≤ 1.9) were synthesized by a solution-based procedure and used as anode materials for Li-ion batteries (LIBs) and Na-ion batteries (SIBs). Among the compositions tested, Ni₀₉Sn-based electrodes exhibited the best performance in both LIBs and SIBs. As LIB anodes, Ni₀₉Sn-based electrodes delivered charge-discharge capacities of 980 mAh g⁻¹ after 340 cycles at 0.2 A g⁻¹ rate, which surpassed their maximum theoretical capacity considering that only Sn is lithiated. A kinetic characterization of the charge-discharge process demonstrated the electrode performance to be aided by a significant pseudocapacitive contribution that compensated for the loss of energy storage capacity associated to the solid-electrolyte interphase formation. This significant pseudocapacitive contribution, which not only translated into higher capacities but also longer durability, was associated to the small size of the crystal domains and the proper electrode composition. The performance of NixSn-based electrodes toward Na-ion storage was also characterized, reaching significant capacities above 200 mAh g⁻¹ at 0.1 A g⁻¹ but with a relatively fast fade over 120 continuous cycles. A relatively larger pseudocapacitive contribution was obtained in Ni Sn-based electrodes for SIBs when compared with LIBs, consistently with the lower contribution of the Na ion diffusion associated to its larger size

Growth of Au-Pd2Sn Nanorods via Galvanic Replacement and Their Catalytic Performance on Hydrogenation and Sonogashira Coupling Reactions

Altres ajuts: Beatriu de Pinós postdoctoral grant (2013 BP-A00344)Colloidal PdSn and Au-PdSn nanorods (NRs) with tuned size were produced by the reduction of Pd and Sn salts in the presence of size- and shape-controlling agents and the posterior growth of Au tips through a galvanic replacement reaction. PdSn and Au-PdSn NRs exhibited high catalytic activity toward quasi-homogeneous hydrogenation of alkenes (styrene and 1-octene) and alkynes (phenylacetylene and 1-octyne) in dichloromethane. Au-PdSn NRs showed higher activity than PdSn for 1-octene, 1-octyne, and phenylacetylene. In Au-PdSn heterostructures, X-ray photoelectron spectroscopy evidenced an electron donation from the PdSn NR to the Au tips. Such heterostructures showed distinct catalytic behavior in the hydrogenation of compounds containing a triple bond such as tolan. This can be explained by the aurophilicity of triple bonds. To further study this effect, PdSn and Au-PdSn NRs were also tested in the Sonogashira coupling reaction between iodobenzene and phenylacetylene in N,N-dimethylformamide. At low concentration, this reaction provided the expected product, tolan. However, at high concentration, more reduced products such as stilbene and 1,2-diphenylethane were also obtained, even without the addition of H. A mechanism for this unexpected reduction is proposed