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PubMed2026

Minimal Transport Units Govern Oxygen-Defect Stabilization and Transport for Lightweight Solid Electrolytes.

Solid electrolytes are central to electrochemical energy technologies, including fuel cells, sensors, catalysis, membrane separation, and electrolyser. However, most established oxide-ion solid electrolytes are built around heavy B-site cations embedded in rigid and highly connected coordination frameworks, leading to widespread high-weight and sluggish ionic transport that is strongly coupled to large-amplitude lattice relaxations. This intrinsic challenge hinders further performance optimization and constrains the rational design of lightweight electrolytes. Herein, we propose a minimal transport unit-based design paradigm that combines simplified structural motifs with light-element chemistry, enabled by the exceptional flexibility of B-O polyhedra in coordination, rotation, deformation, and connectivity. As a proof of concept, Sc1- xZnxBO3- x /2, constructed from isolated BO3 units, exhibits high oxide ion conductivity (σ(1000°C) ∼ 1.5 × 10-2 S/cm), alongside excellent thermo-mechanical stability. Oxygen vacancies are stabilized through the formation of B2O5 units rather than isolated BO2 species. Long-range oxide-ion migration is mediated by dynamic oxygen exchange between minimal BO3 and B2O5 units via continuous breaking and reforming of B2O5 units, with transient BO2 configurations as intermediates. This study demonstrates minimal transport units as a governing principle for defect stabilization and ionic conduction in lightweight solid electrolytes, offering a general design framework for portable and scalable high-temperature energy technologies.

NMR spectroscopy and variable‐temperature P↗

PubMed2026

Enhanced Performance in All-Inorganic AgBiS2 Photodetectors via Oxygen-Inhibited Spray Pyrolysis Deposition.

AgBiS2 has emerged as a promising optoelectronic material due to its broad spectral response and strong light absorption. However, the current use of high-boiling solvents and organic buffers restricts fundamental studies and further performance optimization of AgBiS2's intrinsic properties. In this study, we develop an organic buffer-free AgBiS2 photodetector prepared using a low-temperature ultrasonic spray pyrolysis technique. Our theoretical analysis revealed that oxygen doping alters the optoelectronic characteristics by enhancing the density of states near the Fermi level, leading to consequent severe nonradiative charge carrier recombination. By incorporating excess thiourea while maintaining optimal substrate temperature for enhanced crystallinity, we successfully suppress oxygen defects and consequently improve photodetection performance. The optimized device exhibits a high responsivity of 0.046 A W-1 at 1050 nm, a low noise level (<8.5 × 10-19 A2 Hz-1), and a fast response time (0.07 μs rise, 0.60 μs decay). Benefiting from the rapid response, the photodetector delivers high-resolution imaging with sharp edge definition. This work eliminates the interference of organic buffer layers to directly reveal how oxygen defect modulation affects the intrinsic optoelectronic properties of AgBiS2, offering a scalable pathway for high-performance, solution-processed photodetectors.

near-infrared detector↗

PubMed2026

Decoupled Synthesis Pathway via Precursor Functionalization Stabilizes High-Voltage Nickel-Based Cathodes.

Nickel-based layered cathodes are promising candidates for high-performance, high-energy lithium-ion batteries, yet their high-voltage application is jointly limited by synthesis-inherited structural defects and an unstable lattice oxygen framework. Here, we show that both limitations can be overcome by decoupled synthesis pathway (DSP) via La/Nb oxalate functionalization of the Ni0.6Co0.1Mn0.3(OH)2 precursor. Unlike the conventional coupled synthesis pathway (CSP) where precursor dehydration and Li2CO3 decomposition overlap in temperature, the DSP introduces a low‑temperature decomposition of La/Nb oxalates at 200°C, which effectively avoids localized contact between the precursor and Li2CO3 and shifts Li2CO3-related reactions to high temperatures. This allows sequential precursor dehydroxylation, rock‑salt (RS) intermediate formation, and layered‑phase transformation over a broad temperature window. The resulting LiNi0.6Co0.1Mn0.3O2 cathode with La/Nb functionalization (NCM-LN) features a uniform surface LaNiO3 perovskite heterostructure and a Nb‑doped layered bulk with suppressed RS and spinel defects. Consequently, under 4.5 V operation (vs. Li+/Li), NCM-LN exhibits homogeneous Li+ (de)intercalation, and a stabilized oxygen framework. In graphite||NCM-LN full cells, NCM-LN retains 80.1% of its capacity after 2000 cycles at 1C, substantially outperforming the pristine cathode. This decoupling strategy is broadly effective across various Ni‑based systems, providing a generalizable route toward high‑energy, long‑life cathode materials.

decoupled synthesis pathway↗

PubMed2025

Caffeic acid phenethyl ester protects renal tubular epithelial cells against ferroptosis in diabetic kidney disease via restoring PINK1-mediated mitophagy.

Mounting evidence indicates that renal tubular ferroptosis plays a crucial role in the progression of diabetic kidney disease (DKD). Caffeic acid phenethyl ester (CAPE), derived from propolis, a precious resinous substance synthesized by various bee species, has garnered broad attention in biomedical research. This study aims to explore the mechanism by which CAPE protects renal tubular epithelial cells (TECs) against ferroptosis in DKD. DBA/2J mice were administered streptozotocin (STZ) by intraperitoneal injection, fed a high-fat diet (HFD) and treated with CAPE. The findings revealed significant changes in ferroptosis markers. In diabetic mice and TECs under high-glucose (HG) conditions, levels of glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11) decreased, while transferrin receptor 1 (TFR1) increased. These changes were accompanied by a reduction in antioxidant capability and the accumulation of malondialdehyde (MDA). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed that the intersection targets of CAPE and ferroptosis were mainly located in the mitochondria and exhibited high enrichment values in mitophagy. Further investigations revealed that HG induced a depolarization of mitochondrial membrane potential and an excessive level of mitochondrial reactive oxygen species (ROS), accompanied by defective mitophagy. The administration of CAPE inhibited exacerbated ferroptosis and rescued defective mitophagy induced by DKD. In addition, CAPE restored PTEN-induced putative kinase 1 (PINK1) levels, which were markedly diminished in the kidneys of DKD mice and TECs subjected to HG. Molecular docking simulation experiments suggested that CAPE is steadily bound to the PINK1 active pocket. Cellular Thermal Shift Assay (CETSA) and Drug Affinity Responsive Target Stability assay (DARTS) showed that CAPE enhances the thermal stability of the PINK1 protein within a specific temperature range and protects the PINK1 protein from degradation by proteolytic enzymes. These results confirm that CAPE interacts with PINK1 as its specific target. However, the positive outcomes of CAPE treatment on ferroptosis were nullified by the PINK1 siRNA. This research indicates that CAPE has potential therapeutic benefits for DKD by protecting renal TECs against ferroptosis via rescuing PINK1-mediated mitophagy. These findings suggest that CAPE shows potential as a therapeutic agent to prevent tubular injury in DKD.

Animals↗

PubMed2024

Advances in serum thyroid hormone levels and seizures.

Epilepsy, a common neurological disorder, is characterized by paroxysmal, short-term, repetitive, and stereotypical features, significantly impacting patients' quality of life. Currently, the pathogenesis of epilepsy remains incompletely understood. Changes in neuronal excitability, imbalances in glutamate and gamma-aminobutyric acid (GABA) levels, alterations in the activity of GABA receptors, and dysfunction of GABA receptors are considered closely related to its occurrence. Thyroid hormones, vital for human growth and development, also play a crucial role in the nervous system. They mediate oxidative stress, influence reactive oxygen species production, affect mitochondrial function and neuronal excitability, and modulate glutamate and GABA levels. Also, they combine with thyroid hormone receptors and exert genomic effects by regulating the expression of numerous genes. However, once there are defects in thyroid hormone signaling, these defects may lead to severe neurodevelopmental disorders that are associated with an increased frequency of seizures. The impact of antiseizure medications (ASMs) on serum thyroid hormone levels, particularly traditional ASMs, has been extensively studied. It is reported that conventional ASMs such as phenobarbital, phenytoin sodium, carbamazepine, and valproate sodium were more likely to induce subclinical hypothyroidism (elevated TSH with normal FT4) or isolated hypothyroidism (decreased FT4 with normal TSH). However, the new ASMs, such as levetiracetam, have no effect on thyroid hormone levels. Together, seizures not only affect thyroid hormone levels, but abnormal thyroid hormone levels can also influence seizures. However, the precise mechanism underlying the interaction between serum thyroid hormone levels and seizures remains unclear. This review aims to explore the relationship between thyroid hormone levels and seizures, along with the underlying mechanisms.

Humans↗

PubMed2026

Activation of pro-survival autophagy by a small molecule promoting p62 oligomerization.

Autophagy is a critical mechanism of cellular quality control, orchestrated by selective autophagy receptor (SAR) proteins. Pharmacologically enhancing the cargo-targeting capacity of SARs presents an attractive but underexplored strategy for the precise therapeutic activation of autophagy. Here, we characterize SQ-1, a small-molecule activator of autophagy that engages the prototypical SAR protein p62/sequestosome-1 (SQSTM1). We show that SQ-1 sensitizes p62 to oxidation and promotes its disulfide-mediated oligomerization in response to mitochondrial reactive oxygen species (ROS). This ROS-dependent activation of p62-mediated selective autophagy enhances the clearance of ROS-generating mitochondria and restores cell viability in models of Niemann-Pick type C1 disease, which is marked by impaired autophagic flux. In summary, the unique mode of action of SQ-1 enables self-regulated autophagy activation, offering a potential therapeutic strategy for lysosomal storage disorders and a broader spectrum of age-related diseases characterized by defective autophagy.

Niemann-Pick type C1 disease↗

PubMed2025

Bidirectional shifts in Pm20d1 expression impact thermogenesis and metabolism.

BACKGROUND: Peptidase M20 domain containing 1 (PM20D1) is a secreted N-fatty acyl amino synthase and hydrolase that controls tissue and blood levels of N-fatty acyl amino acids. In brown adipocytes, N-fatty acyl amino acids bind to mitochondria and act as uncouplers of mitochondria, independent of UCP1. Interventions aimed at increasing or inhibiting PM20D1 expression considerably impact energy balance and metabolism; however, little is known about naturally occurring variants of the PM20D1/Pm20d1 gene and their impact on phenotype. METHODS: In vivo, gene expression of Pm20d1 in BALB/c, C57BL/6, and Ucp1 KO in brown adipose tissue and other metabolic tissues was measured. In vitro, transcriptional activity of Pm20d1 and brown adipocytes' oxygen consumption in primary culture were assessed. Human PM20D1 circulating levels were quantified. In silico analysis of the Pm20d1 gene sequencing and human polymorphisms associated with PM20D1 was performed. RESULTS: Here, we identified a gain-of-function variant in the Pm20d1 promoter region present in BALB/c mice and absent in C57BL/6 mice. The presence of this variant is accompanied by increased expression of Pm20d1 in brown and white adipose tissues, muscle, liver, and hypothalamus; moreover, it leads to increased cold tolerance and UCP1-independent brown adipose tissue mitochondrial respiration. Inhibition of Pm20d1 in brown adipose tissue results in defective cold tolerance in BALB/c, whereas the brown adipose tissue overexpression of Pm20d1 results in increased cold tolerance in C57BL/6 mice. In humans, variants of the PM20D1 gene are associated with changes in body mass index, whereas at least one variant in the promoter region is associated with increased body mass index and metabolic syndrome. CONCLUSION: Thus, PM20D1 plays a bidirectional role in regulating thermogenesis and body mass, and, at least in part, variants in the promoter region can partially explain the differences in PM20D1 expression and its impact on the metabolic phenotype.

Thermogenesis↗

PubMed2026

Hypertensive mt. tRNAIle4263A>G mutation orchestrates vascular senescence and apoptosis by activation of mitochondria-ER interplay.

The pathogenic mechanism underlying diseases caused by mitochondrial DNA (mtDNA) mutation, including hypertension, persists as an unresolved global challenge. Although mutation-induced mitochondrial defects have been well characterized, how these mito-perturbations are converted into critical intermediary signaling cascades and contribute to diseases remain unknown. Here, using human induced pluripotent stem cell (hiPSC)-derived vascular organoids (VOs) and vascular cells, the hypertensive mt. tRNAIle4263A > G mutation was identified to induce vascular senescence, apoptosis and vascular-specific dysfunction through mitochondria-endoplasmic reticulum (ER) interaction. For the first time, this study mapped the transcriptional reprogramming landscape of human VOs carrying this mutation. Through systematic screening and functional validation, ER stress was screened out, together with downstream mitochondria-associated ER membranes-mitochondrial Ca2+ overload resulting in vascular abnormality. Pathological reactive oxygen species (ROS) elevation, driven by tRNAIle destabilization and bioenergetic failure, acts as the primary instigator of maladaptive ER stress activation in this cascade. Pharmacological targeting of this axis-using mito-Tempol (a mitochondria-targeted ROS scavenger), Tauro Ursodeoxycholic Acid (an ER stress inhibitor), or RU265 (a highly-selective mitochondrial calcium uniporter inhibitor)-rescues vascular abnormality. This study highlights mt. tRNAIle4263A > G mutation orchestrates vascular pathology through ROS induced activation of inter-organelle communication, resolving a long-standing knowledge gap between mtDNA mutations and diseases and establishing therapeutic nexuses for mtDNA mutation-related cardiovascular diseases.

Hypertension↗

PubMed2026

Pierson syndrome with numerous dilated tubules masquerading as autosomal recessive polycystic kidney disease: a case report.

Pierson syndrome, characterized by congenital nephrotic syndrome, ocular abnormalities, and neurological defects, is caused by biallelic pathogenic variants in LAMB2. LAMB2 encodes laminin β2, a key component of basement membranes that is predominantly expressed in the glomeruli, eyes, and neuromuscular junctions. The renal histopathology of Pierson syndrome typically shows diffuse mesangial sclerosis (DMS), with occasional tubulointerstitial atrophy and fibrosis. We report a case of Pierson syndrome characterized by DMS and prominent tubular dilatation. A fetal ultrasound at 23 weeks of gestation revealed hyperechoic kidneys, which gradually enlarged, accompanied by the onset of anhydramnios from 31 weeks. The patient was delivered at 39 weeks of gestation, weighing 3,132 g, without placentomegaly. Postnatal respiratory failure due to pulmonary hypoplasia required extracorporeal membrane oxygenation, and hemodialysis was initiated for anuria. Left nephrectomy was performed on day 8 of life, revealing replacement of the renal parenchyma by numerous irregularly dilated tubules with eosinophilic casts. The right kidney reached maximal enlargement by 1 month of age and subsequently began to shrink. Ocular findings included bilateral microcoria and cataracts. Whole-exome sequencing identified compound heterozygous truncating variants in LAMB2 (p.Gln1507Ter and p.Gln1622Ter). This case highlights the need to consider Pierson syndrome in the differential diagnosis of prenatally detected hyperechoic and enlarged kidneys, in addition to polycystic kidney disease.

Female↗

PubMed2026

Recent advances in supramolecular macrocycle-based artificial light-harvesting systems.

Artificial light-harvesting systems (ALHSs) inspired by the antenna function of natural photosynthesis provide molecular platforms for collecting excitation energy and directing it to emissive or reactive acceptors. In many supramolecular ALHSs, however, practical performance is limited by poorly defined donor-acceptor orientation, aggregation-caused quenching (ACQ), interfacial defects, and limited stability in aqueous or complex media. Supramolecular macrocycles-particularly pillar[n]arenes (PAs), cucurbit[n]urils (CBs), calixarenes (CAs), cyclodextrins (CDs), and supramolecular coordination complexes (SCCs)-offer a useful design space because their cavities, pre-organized scaffolds, and reversible non-covalent interactions can confine chromophores, tune local donor/acceptor ratios, and modulate Förster resonance energy transfer (FRET). This Review systematically examines the unique structural advantages and assembly mechanisms of the five macrocyclic families, with an emphasis on their use in constructing ALHSs-from single-step to cascaded FRET-and in advancing aqueous photocatalysis, near-infrared bioimaging, panchromatic fluorescence modulation, and singlet oxygen generation. The resulting structure-property-application framework is intended to guide the rational design of macrocycle-assisted photofunctional materials while avoiding overextension of the photosynthesis analogy.

Journal Article↗

PubMed2025

Identification and Validation of a Previously Missed Mutational Signature in Colorectal Cancer.

Mutational signature analysis has greatly enhanced our understanding of the mutagenic processes found in cancer and normal tissues. As part of a recent study, we analyzed 802 treatment-naïve, microsatellite-stable colorectal cancers (CRC) and identified a de novo signature, SBS_D, which was conservatively decomposed into SBS18, a signature associated with reactive oxygen species. Here, we re-evaluate this decomposition and provide evidence that SBS_D represents a distinct mutational process from that of SBS18. Through an independent analysis of 2,616 whole-genome sequenced microsatellite-stable CRCs across three distinct cohorts, we demonstrate that SBS_D is consistently present at a similar prevalence, suggesting that this signature may have been previously overlooked. Using a naïve decomposition approach, we demonstrate that the pattern of SBS_D better aligns with signatures previously associated with deficiencies in DNA polymerase delta (POLD1) proofreading and mismatch repair. However, multiple lines of evidence, including the absence of pathogenic mutations in the exonuclease domain of POLD1 or in mismatch repair-associated genes, indicate that SBS_D is not driven by canonical defects in these DNA repair pathways. Overall, this study identifies a previously unrecognized mutational signature in microsatellite-stable CRC and proposes that its etiology may be linked to DNA repair infidelity emerging late in tumor development in samples without canonical defects in DNA repair pathways.

Journal Article↗

PubMed2026

IL17 signaling promotes oocyte developmental competence acquisition during maturation.

BACKGROUND: Defects in the acquisition of oocyte developmental competence during the maturation process causes subfertility or infertility in animals and humans. Understanding the regulatory mechanisms of oocyte maturation is essential for reproductive biology and medicine. Follicular fluid (FF) is an important microenvironment governing oocyte maturation. METHODS: A tandem mass tags (TMT)-based comparative FF proteomic analysis was employed to identify FF proteins that are potentially crucial for oocyte maturation. A very large number of pig and mouse oocytes (approximately 20,000) and embryos (over 13,000, including somatic cell nuclear transfer, parthenogenetic activation, and in vitro fertilization embryos) were used to investigate the effects of identified FF proteins on in vitro oocyte maturation and subsequent in vitro and in vivo embryo development. RNA sequencing, quantitative PCR, enzyme-linked immunosorbent assays, and immunofluorescence were used to study the expression patterns and action mechanisms of identified FF proteins in oocytes. In addition, intra-oocyte levels of glutathione and reactive oxygen species were measured to assess redox homeostasis. RESULTS: Interleukin 17D (IL17D) was identified as an important FF protein and it is significantly upregulated in porcine FF during oocyte maturation. IL17D promotes oocyte maturation by enhancing bidirectional communication between oocytes and cumulus cells, via upregulating CX43 expression and transzonal projections, which helps to maintain oocyte redox homeostasis and nuclear-cytoplasmic synchrony. IL17D treatment of oocytes enhances subsequent in vitro and in vivo full-term embryo development by modulating lipid metabolism and histone modification reprogramming. IL17D exerts its function via activating IL17 signaling through binding to CD93. Two other IL17 family members, IL17A and IL17F, also enhance oocyte maturation quality. IL17D displays a conserved expression pattern and function in pig and mouse oocytes. CONCLUSIONS: This study reveals the critical roles of IL17D in regulating oocyte developmental competence acquisition during maturation by activating IL17 signaling. The findings provide valuable insights into the molecular mechanisms underlining oocyte developmental potential acquisition and may help to develop methods for efficient production of oocytes for assisted reproduction.

Animals↗

PubMed2026

Calcium-Sensing Receptor Activation Disrupts Phosphatidylserine Asymmetry and Promotes Calcium Oxalate Crystal-Induced Epithelial Injury in Renal Tubular Epithelial Cells.

BACKGROUND: Calcium oxalate (CaOx) crystal retention on the renal tubular epithelium is a key step in urolithiasis. Phosphatidylserine (PS) exposure may facilitate crystal-cell adhesion, but the upstream signaling mechanisms and the relative contributions of impaired inward PS flipping versus outward PS redistribution remain unclear. MATERIALS AND METHODS: Global proteomic profiling using 2-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry (2-DE/MALDI-TOF/TOF) in an immortalized human proximal tubular epithelial cell line (HK-2) cells exposed to calcium oxalate monohydrate (COM) identified upregulation of the calcium-sensing receptor (CaSR). HK-2 cells were treated with COM with or without the CaSR antagonist NPS2390 or the CaSR agonist gadolinium chloride (GdCl3). Bidirectional PS transport was assessed using an N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) (NBD)-labeled phosphatidylserine (NBD-PS) fluorescence-quenching assay, and surface PS exposure was measured by annexin V binding. Aminophospholipid translocase (APLT) expression, APLT-dependent inward PS transport, crystal adhesion, oxidative stress, and apoptosis-related signaling were evaluated. RESULTS: COM increased CaSR expression, enhanced surface PS exposure, and promoted crystal adhesion with concurrent oxidative stress and apoptosis-related signaling. COM induced a CaSR-sensitive defect in APLT-dependent inward PS flipping: NPS2390 partially restored inward PS transport and APLT expression, whereas GdCl3 exacerbated these changes. In contrast, COM-enhanced outward PS redistribution and externalization was largely unaffected by CaSR modulation, indicating relative CaSR insensitivity of the outward process. Consistently, CaSR activation aggravated, while CaSR inhibition attenuated, crystal adhesion and injury-related readouts. CONCLUSIONS: COM was associated with enhanced crystal-cell adhesion, CaSR activation, and a CaSR-sensitive impairment of APLT-dependent inward PS flipping, whereas enhanced outward PS redistribution appeared largely CaSR-insensitive. Pharmacologic inhibition of CaSR attenuated epithelial injury and crystal retention-related readouts, suggesting that CaSR may represent a potential therapeutic target.

Receptors, Calcium-Sensing↗