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1.
Mol Cell ; 82(15): 2885-2899.e8, 2022 08 04.
Article in English | MEDLINE | ID: mdl-35841888

ABSTRACT

Translated small open reading frames (smORFs) can have important regulatory roles and encode microproteins, yet their genome-wide identification has been challenging. We determined the ribosome locations across six primary human cell types and five tissues and detected 7,767 smORFs with translational profiles matching those of known proteins. The human genome was found to contain highly cell-type- and tissue-specific smORFs and a subset that encodes highly conserved amino acid sequences. Changes in the translational efficiency of upstream-encoded smORFs (uORFs) and the corresponding main ORFs predominantly occur in the same direction. Integration with 456 mass-spectrometry datasets confirms the presence of 603 small peptides at the protein level in humans and provides insights into the subcellular localization of these small proteins. This study provides a comprehensive atlas of high-confidence translated smORFs derived from primary human cells and tissues in order to provide a more complete understanding of the translated human genome.


Subject(s)
Gene Expression Regulation , Ribosomes , Genome, Human/genetics , Humans , Open Reading Frames/genetics , Protein Biosynthesis , Proteins/metabolism , RNA/metabolism , Ribosomes/genetics , Ribosomes/metabolism
2.
Proc Natl Acad Sci U S A ; 121(28): e2307107121, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38959040

ABSTRACT

Despite evolutionary biology's obsession with natural selection, few studies have evaluated multigenerational series of patterns of selection on a genome-wide scale in natural populations. Here, we report on a 10-y population-genomic survey of the microcrustacean Daphnia pulex. The genome sequences of [Formula: see text]800 isolates provide insights into patterns of selection that cannot be obtained from long-term molecular-evolution studies, including the following: the pervasiveness of near quasi-neutrality across the genome (mean net selection coefficients near zero, but with significant temporal variance about the mean, and little evidence of positive covariance of selection across time intervals); the preponderance of weak positive selection operating on minor alleles; and a genome-wide distribution of numerous small linkage islands of observable selection influencing levels of nucleotide diversity. These results suggest that interannual fluctuating selection is a major determinant of standing levels of variation in natural populations, challenge the conventional paradigm for interpreting patterns of nucleotide diversity and divergence, and motivate the need for the further development of theoretical expressions for the interpretation of population-genomic data.


Subject(s)
Daphnia , Genome , Selection, Genetic , Animals , Daphnia/genetics , Genome/genetics , Evolution, Molecular , Genetic Variation , Genetics, Population/methods
3.
Genome Res ; 33(10): 1690-1707, 2023 10.
Article in English | MEDLINE | ID: mdl-37884341

ABSTRACT

The rumen undergoes developmental changes during maturation. To characterize this understudied dynamic process, we profiled single-cell transcriptomes of about 308,000 cells from the rumen tissues of sheep and goats at 17 time points. We built comprehensive transcriptome and metagenome atlases from early embryonic to rumination stages, and recapitulated histomorphometric and transcriptional features of the rumen, revealing key transitional signatures associated with the development of ruminal cells, microbiota, and core transcriptional regulatory networks. In addition, we identified and validated potential cross-talk between host cells and microbiomes and revealed their roles in modulating the spatiotemporal expression of key genes in ruminal cells. Cross-species analyses revealed convergent developmental patterns of cellular heterogeneity, gene expression, and cell-cell and microbiome-cell interactions. Finally, we uncovered how the interactions can act upon the symbiotic rumen system to modify the processes of fermentation, fiber digestion, and immune defense. These results significantly enhance understanding of the genetic basis of the unique roles of rumen.


Subject(s)
Metagenome , Microbiota , Sheep/genetics , Animals , Transcriptome , Rumen , Ruminants/genetics
4.
Circ Res ; 134(8): e72-e91, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38456298

ABSTRACT

BACKGROUND: CNP (C-type natriuretic peptide), an endogenous short peptide in the natriuretic peptide family, has emerged as an important regulator to govern vascular homeostasis. However, its role in the development of atherosclerosis remains unclear. This study aimed to investigate the impact of CNP on the progression of atherosclerotic plaques and elucidate its underlying mechanisms. METHODS: Plasma CNP levels were measured in patients with acute coronary syndrome. The potential atheroprotective role of CNP was evaluated in apolipoprotein E-deficient (ApoE-/-) mice through CNP supplementation via osmotic pumps, genetic overexpression, or LCZ696 administration. Various functional experiments involving CNP treatment were performed on primary macrophages derived from wild-type and CD36 (cluster of differentiation 36) knockout mice. Proteomics and multiple biochemical analyses were conducted to unravel the underlying mechanism. RESULTS: We observed a negative correlation between plasma CNP concentration and the burden of coronary atherosclerosis in patients. In early atherosclerotic plaques, CNP predominantly accumulated in macrophages but significantly decreased in advanced plaques. Supplementing CNP via osmotic pumps or genetic overexpression ameliorated atherosclerotic plaque formation and enhanced plaque stability in ApoE-/- mice. CNP promoted an anti-inflammatory macrophage phenotype and efferocytosis and reduced foam cell formation and necroptosis. Mechanistically, we found that CNP could accelerate HIF-1α (hypoxia-inducible factor 1-alpha) degradation in macrophages by enhancing the interaction between PHD (prolyl hydroxylase domain-containing protein) 2 and HIF-1α. Furthermore, we observed that CD36 bound to CNP and mediated its endocytosis in macrophages. Moreover, we demonstrated that the administration of LCZ696, an orally bioavailable drug recently approved for treating chronic heart failure with reduced ejection fraction, could amplify the bioactivity of CNP and ameliorate atherosclerotic plaque formation. CONCLUSIONS: Our study reveals that CNP enhanced plaque stability and alleviated macrophage inflammatory responses by promoting HIF-1α degradation, suggesting a novel atheroprotective role of CNP. Enhancing CNP bioactivity may offer a novel pharmacological strategy for treating related diseases.


Subject(s)
Atherosclerosis , Plaque, Atherosclerotic , Humans , Mice , Animals , Plaque, Atherosclerotic/metabolism , Atherosclerosis/drug therapy , Atherosclerosis/genetics , Atherosclerosis/prevention & control , Macrophages/metabolism , Foam Cells/metabolism , Mice, Knockout , Apolipoproteins E , Mice, Inbred C57BL
5.
J Biol Chem ; : 107486, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38897570

ABSTRACT

Aberrant regulation of signal transduction pathways can adversely derail biological processes for tissue development. One such process is the embryonic eyelid closure that is dependent on the Mitogen-Activated Protein Kinase Kinase Kinase 1 (MAP3K1). Map3k1 knockout in mice results in defective eyelid closure and an autosomal recessive eye-open at birth phenotype. We have shown that in utero exposure to dioxin, a persistent environmental toxicant, induces the same eye defect in Map3k1+/- heterozygous but not wild type pups. Here we explore the mechanisms of the Map3k1 (gene) and dioxin (environment) interactions (GxE) underlying defective eyelid closure. We show that, acting through the Aryl Hydrocarbon Receptor (AHR), dioxin activates Epidermal Growth Factor Receptor (EGFR) signaling, which in turn depresses MAP3K1-dependent Jun N-terminal Kinase (JNK) activity. The dioxin mediated JNK repression is moderate but is exacerbated by Map3k1 heterozygosity. Therefore, dioxin exposed Map3k1+/- embryonic eyelids have a marked reduction of JNK activity, accelerated differentiation and impeded polarization in the epithelial cells. Knocking out Ahr or Egfr in eyelid epithelium attenuates the open-eye defects in dioxin-treated Map3k1+/- pups, whereas knockout of Jnk1 and S1pr that encodes the Sphigosin-1-phosphate (S1P) receptors upstream of the MAP3K1-JNK pathway potentiates the dioxin toxicity. Our novel findings show that the crosstalk of AHR, EGFR and S1P-MAP3K1-JNK pathways determines the outcome of dioxin exposure. Thus, gene mutations targeting these pathways are potential risk factors for the toxicity of environmental chemicals.

6.
PLoS Pathog ; 19(6): e1011011, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37276223

ABSTRACT

Isoprothiolane (IPT) resistance has emerged in Magnaporthe oryzae, due to the long-term usage of IPT to control rice blast in China, yet the mechanisms of the resistance remain largely unknown. Through IPT adaptation on PDA medium, we obtained a variety of IPT-resistant mutants. Based on their EC50 values to IPT, the resistant mutants were mainly divided into three distinct categories, i.e., low resistance (LR, 6.5 ≤ EC50 < 13.0 µg/mL), moderate resistance 1 (MR-1, 13.0 ≤ EC50 < 25.0 µg/mL), and moderate resistance 2 (MR-2, 25.0 ≤ EC50 < 35.0 µg/mL). Molecular analysis of MoIRR (Magnaporthe oryzae isoprothiolane resistance related) gene demonstrated that it was associated only with the moderate resistance in MR-2 mutants, indicating that other mechanisms were associated with resistance in LR and MR-1 mutants. In this study, we mainly focused on the characterization of low resistance to IPT in M. oryzae. Mycelial growth and conidial germination were significantly reduced, indicating fitness penalties in LR mutants. Based on the differences of whole genome sequences between parental isolate and LR mutants, we identified a conserved MoVelB gene, encoding the velvet family transcription factor, and genetic transformation of wild type isolate verified that MoVelB gene was associated with the low resistance. Based on molecular analysis, we further demonstrated that the velvet family proteins VelB and VeA were indispensable for IPT toxicity and the deformation of the VelB-VeA-LaeA complex played a vital role for the low IPT-resistance in M. oryzae, most likely through the down-regulation of the secondary metabolism-related genes or CYP450 genes to reduce the toxicity of IPT.


Subject(s)
Ascomycota , Magnaporthe , Oryza , Magnaporthe/genetics , Thiophenes , Oryza/genetics , Plant Diseases
7.
Exp Cell Res ; 435(1): 113910, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38185251

ABSTRACT

Esophageal squamous cell carcinoma (ESCC) is an aggressive malignant disease with a poor prognosis. We previously found that p62 presented a marked nuclear-cytoplasmic translocation in ESCC cells as compared that in normal esophageal epithelial cells, but its effects on ESCC cells remain unclear. This study aims to clarify the impacts of different cellular localization of p62 on the function of ESCC cells and the underlying molecular mechanisms. We here demonstrated that cytoplasmic p62 enhances the migration and invasion abilities of esophageal cancer cells, whereas nuclear p62 has no effect. We further explored the interaction protein of p62 by using GST pull-down experiment and identified EPLIN as a potential protein interacting with p62. In addition, reducing EPLIN expression significantly inhibited the migration and invasion of ESCC cells, which were rescued when EPLIN expression was restored after the p62 knockdown. At a molecular level, p62 in cytoplasm positively regulated the expression of EPLIN via enhancing its protein stability. Data from the TCGA and GEO database displayed a significant up-regulation of EPLIN mRNA expression in ESCC tissues compared with corresponding paired esophageal epithelial samples. Our findings present evidence that the nuclear-cytoplasmic translocation of p62 protein contributes to an aggressive malignancy phenotype, providing candidate molecular biomarkers and potential molecular targets for the diagnosis and treatment of ESCC.


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Humans , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation , Cytoplasm/metabolism , Esophageal Neoplasms/pathology , Esophageal Squamous Cell Carcinoma/pathology , Gene Expression Regulation, Neoplastic/genetics , Neoplasm Invasiveness/genetics , Sequestosome-1 Protein/genetics , Sequestosome-1 Protein/metabolism
8.
Nature ; 565(7737): 82-85, 2019 01.
Article in English | MEDLINE | ID: mdl-30455423

ABSTRACT

Levallois approaches are one of the best known variants of prepared-core technologies, and are an important hallmark of stone technologies developed around 300,000 years ago in Africa and west Eurasia1,2. Existing archaeological evidence suggests that the stone technology of east Asian hominins lacked a Levallois component during the late Middle Pleistocene epoch and it is not until the Late Pleistocene (around 40,000-30,000 years ago) that this technology spread into east Asia in association with a dispersal of modern humans. Here we present evidence of Levallois technology from the lithic assemblage of the Guanyindong Cave site in southwest China, dated to approximately 170,000-80,000 years ago. To our knowledge, this is the earliest evidence of Levallois technology in east Asia. Our findings thus challenge the existing model of the origin and spread of Levallois technologies in east Asia and its links to a Late Pleistocene dispersal of modern humans.


Subject(s)
Archaeology , Caves , Fossils , Hominidae , Tool Use Behavior , Africa , Animals , China , Europe , Asia, Eastern , History, Ancient , Humans , Time Factors
9.
Cereb Cortex ; 34(3)2024 03 01.
Article in English | MEDLINE | ID: mdl-38517173

ABSTRACT

OBJECTIVES: Observational studies link elevated plasma homocysteine (Hcy) with vascular disease. Our aim was to assess the gender difference in the association between the plasma tHcy level and brain atrophy and identify the possible influencer. We employed Mendelian randomization (MR) to explore the causal relationship between plasma tHcy level, estradiol level, and brain atrophy. METHODS: A total of 687 patients with brain atrophy were included, and gender-specific subgroup analyses in association between tHcy and brain atrophy are conducted. From genome-wide association studies, we selected genetic variants (P < 5 × 10-8) for the plasma tHcy level and estradiol level. We investigated the degree of brain atrophy (including gray matter volume and total brain volume) in the UK biobank (n = 7,916). The inverse variance-weighted and several sensitivity MR regression analyses were carried out. RESULTS: The plasma tHcy level was significantly associated with brain atrophy for females, but not for males. An MR study showed that there was little evidence of the causal link between elevated plasma tHcy and brain atrophy. On the other hand, we found evidence to support causality for genetically decreased estradiol with higher risk of brain atrophy. Furthermore, genetic predisposition to elevated plasma tHcy was associated with a lower estradiol level. CONCLUSIONS: The influence of estradiol on the association between tHcy and brain atrophy deserves further investigation.


Subject(s)
Genome-Wide Association Study , Neurodegenerative Diseases , Male , Female , Humans , Mendelian Randomization Analysis , Brain/diagnostic imaging , Brain/pathology , Neurodegenerative Diseases/pathology , Atrophy/pathology , Estradiol
10.
Chem Soc Rev ; 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38904176

ABSTRACT

Metal-catalyzed highly Markovnikov-type selective hydrofunctionalization of terminal alkynes provides a straightforward and atom-economical route to access 1,1-disubstituted alkenes, which have a wide range of applications in organic synthesis. However, the highly Markovnikov-type selective transformations are challenging due to the electronic and steric effects during the addition process. With the development of metal-catalyzed organic synthesis, different metal catalysts have been developed to solve this challenge, especially for platinum group metal catalysts. In this perspective, we review homogeneous metal-catalyzed Markovnikov-type selective hydrofunctionalization of terminal alkynes according to the classified element types as well as reaction mechanisms. Future avenues for investigation are also presented to help expand this exciting field.

11.
Mol Biol Evol ; 40(11)2023 Nov 03.
Article in English | MEDLINE | ID: mdl-37863047

ABSTRACT

The field of genomics has ushered in new methods for studying molecular-genetic variation in natural populations. However, most population-genomic studies still rely on small sample sizes (typically, <100 individuals) from single time points, leaving considerable uncertainties with respect to the behavior of relatively young (and rare) alleles and, owing to the large sampling variance of measures of variation, to the specific gene targets of unusually strong selection. Genomic sequences of ∼1,700 haplotypes distributed over a 10-year period from a natural population of the microcrustacean Daphnia pulex reveal evolutionary-genomic features at a refined scale, including previously hidden information on the behavior of rare alleles predicted by recent theory. Background selection, resulting from the recurrent introduction of deleterious alleles, appears to strongly influence the dynamics of neutral alleles, inducing indirect negative selection on rare variants and positive selection on common variants. Temporally fluctuating selection increases the persistence of nonsynonymous alleles with intermediate frequencies, while reducing standing levels of variation at linked silent sites. Combined with the results from an equally large metapopulation survey of the study species, classes of genes that are under strong positive selection can now be confidently identified in this key model organism. Most notable among rapidly evolving Daphnia genes are those associated with ribosomes, mitochondrial functions, sensory systems, and lifespan determination.


Subject(s)
Genetics, Population , Genomics , Humans , Biological Evolution , Alleles , Haplotypes , Selection, Genetic , Genetic Variation
12.
Am J Gastroenterol ; 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38084857

ABSTRACT

INTRODUCTION: Despite the serious risks of diabetes with hepatitis C virus (HCV) infection, this preventable comorbidity is rarely a priority for HCV elimination. We aim to examine how a shared care model could eliminate HCV in patients with diabetes (PwD) in primary care. METHODS: There were 27 community-based Diabetes Health Promotion Institutes in each township/city of Changhua, Taiwan. PwD from these institutes from January 2018 to December 2020 were enrolled. HCV screening and treatment were integrated into diabetes structured care through collaboration between diabetes care and HCV care teams. Outcome measures included HCV care continuum indicators. Township/city variation in HCV infection prevalence and care cascades were also examined. RESULTS: Of the 10,684 eligible PwD, 9,984 (93.4%) underwent HCV screening, revealing a 6.18% (n = 617) anti-HCV seroprevalence. Among the 597 eligible seropositive individuals, 507 (84.9%) completed the RNA test, obtaining 71.8% positives. Treatment was initiated by 327 (89.8%) of 364 viremic patients, and 315 (86.5%) completed it, resulting in a final cure rate of 79.4% (n = 289). Overall, with the introduction of antivirals in this cohort, the prevalence of viremic HCV infection dropped from 4.44% to 1.34%, yielding a 69.70% (95% credible interval 63.64%-77.03%) absolute reduction. DISCUSSION: Although HCV prevalence varied, the care cascades achieved consistent results across townships/cities. We have further successfully implemented the model in county-wide hospital-based diabetes clinics, eventually treating 89.6% of the total PwD. A collaborative effort between diabetes care and HCV elimination enhanced the testing and treatment in PwD through an innovative shared care model.

13.
Small ; 20(6): e2304563, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37786270

ABSTRACT

It is substantially challenging for non-centrosymmetric (NCS) Hg-based chalcogenides for infrared nonlinear optical (IR-NLO) applications to realize wide band gap (Eg > 3.0 eV) and sufficient phase-matching (PM) second-harmonic-generation intensity (deff > 1.0 × benchmark AgGaS2 ) simultaneously due to the inherent incompatibility. To address this issue, this work presents a diagonal synergetic substitution strategy for creating two new NCS quaternary Hg-based chalcogenides, AEHgGeS4 (AE = Sr and Ba), based on the centrosymmetric (CS) AEIn2 S4 . The derived AEHgGeS4 displays excellent NLO properties such as a wide Eg (≈3.04-3.07 eV), large PM deff (≈2.2-3.0 × AgGaS2 ), ultra-high laser-induced damage threshold (≈14.8-15 × AgGaS2 ), and suitable Δn (≈0.19-0.24@2050 nm), making them highly promising candidates for IR-NLO applications. Importantly, such excellent second-order NLO properties are primarily attributed to the synergistic combination of tetrahedral [HgS4 ] and [GeS4 ] functional primitives, as supported by detailed theoretical calculations. This study reports the first two NCS Hg-based materials with well-balanced comprehensive properties (i.e., Eg > 3.0 eV and deff > 1.0 × benchmark AgGaS2 ) and puts forward a new design avenue for the construction of more efficient IR-NLO candidates.

14.
Metab Eng ; 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38942196

ABSTRACT

Yarrowia lipolytica is an industrial yeast that can convert waste oil to value-added products. However, it is unclear how this yeast metabolizes lipid feedstocks, specifically triacylglycerol (TAG) substrates. This study used 13C-metabolic flux analysis (13C-MFA), genome-scale modeling, and transcriptomics analyses to investigate Y. lipolytica W29 growth with oleic acid, glycerol, and glucose. Transcriptomics data was used to guide 13C-MFA model construction and to validate the 13C-MFA results. The 13C-MFA data was then used to constrain a genome-scale model (GSM), which predicted Y. lipolytica fluxes, cofactor balance, and theoretical yields of terpene products. The three data sources provided new insights into cellular regulation during catabolism of glycerol and fatty acid components of TAG substrates, and how their consumption routes differ from glucose catabolism. We found that (1) over 80% of acetyl-CoA from oleic acid is processed through the glyoxylate shunt, a pathway that generates less CO2 compared to the TCA cycle, (2) the carnitine shuttle is a key regulator of the cytosolic acetyl-CoA pool in oleic acid and glycerol cultures, (3) the oxidative pentose phosphate pathway and mannitol cycle are key routes for NADPH generation, (4) the mannitol cycle and alternative oxidase activity help balance excess NADH generated from ß-oxidation of oleic acid, and (5) asymmetrical gene expressions and GSM simulations of enzyme usage suggest an increased metabolic burden for oleic acid catabolism.

15.
Ann Surg Oncol ; 31(7): 4250-4260, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38334847

ABSTRACT

BACKGROUND: The prognosis of limited-stage small cell lung cancer (LS-SCLC) after surgery usually is estimated at diagnosis, but how the prognosis actually evolves over time for patients who survived for a predefined time is unknown. METHODS: Data on patients with a diagnosis of LS-SCLC after surgery between 2004 and 2015 were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. The 5-year conditional cancer-specific survival (CCSS) and conditional overall survival (COS) were calculated. RESULTS: This study analyzed 997 patients (555 women, 55.7%) with a median age, of 67 years (interquartile range [IQR], 60-73 years). The 5-year CCSS and COS increased from 44.7% and 38.3%, respectively, at diagnosis to 83.7% and 67.9% at 5 years after diagnosis. Although there were large differences with different stages (stages I, II, and III) at diagnosis (respectively 59.5%, 28.4%; 28.1% for CCSS and 50.6%, 24.8%, and 23.6% for COS), the gap decreased with time, and the rates were similar after 5 years (respectively 85.0%, 80.3%, and 79.4% for CCSS; 65.6%, 56.9%, and 61.3% for COS). The 5-year conditional survival for the patients who received lobectomy was better than for those who received sublobectomy or pneumonectomy. Multivariable analyses showed that only age and resection type were independent predictors for CCSS and COS, respectively, throughout the period. CONCLUSION: Conditional survival estimates for LS-SCLC generally increased over time, with the most significant improvement in patients with advanced stage of disease. Resection type and old age represented extremely important determinants of prognosis after a lengthy event-free follow-up period.


Subject(s)
Lung Neoplasms , Neoplasm Staging , SEER Program , Small Cell Lung Carcinoma , Humans , Lung Neoplasms/surgery , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Female , Small Cell Lung Carcinoma/surgery , Small Cell Lung Carcinoma/mortality , Small Cell Lung Carcinoma/pathology , Middle Aged , Male , Survival Rate , Aged , Prognosis , Follow-Up Studies , Pneumonectomy/mortality , Cohort Studies
16.
Chemistry ; : e202401386, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38837287

ABSTRACT

Vinyl sulfones are crucial building blocks in synthetic chemistry and core structural units of pharmaceutically active molecules, thus extensive investigations have been conducted on the construction of these skeletons. In contrast to the classical synthetic approaches, the radical sulfonylation of alkynes for producing vinyl sulfones has garnered considerable interest because of its mild conditions and high efficiency. Radical sulfonation of alkynes typically begins with the sulfonyl radical attacking the alkynes, followed by further functionalization. Moreover, the association of metal-catalyst-free systems with multicomponent reactions (MCRs) offers an environmentally friendly pathway for efficiently constructing complex scaffolds from readily available partners. However, there is no comprehensive review summarizing the advancements in metal-catalyst-free multicomponent radical sulfonylation of alkynes. Hence, we provide a categorical overview based on the objects of sulfonylation of alkynes (hydrosulfonylation, carbosulfonylation, aminosulfonylation, oxysulfonylation, sulfosulfonylation, selenosulfonylation, and iodosulfonylation), along with interpretations of the reaction mechanisms.

17.
Chemistry ; : e202402152, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38940291

ABSTRACT

The synthesis of strained carbocyclic building blocks is relevant for Medicinal Chemistry, and methylenecyclobutanes are particularly challenging with current synthetic technology. Careful inspection of the reactivity of [1.1.1]propellane and diboron reagents has revealed that bis(catecholato)diboron (B2cat2) can produce a bis(borylated) methylenecyclobutane in a few minutes at room temperature. This reaction constitutes the first example of B-B bond activation by a special apolar hydrocarbon and also the first time that propellane is electrophilically activated by boron. Mechanistic studies including in situ NMR kinetics and DFT calculations demonstrate that the diboron moiety can be directly activated through coordination with the inverted sigma bond of propellane, and reveal that DMF is involved in the stabilization of diboronate ylide intermediates rather than the activation of the B-B bond. These results enable new possibilities for both diboron and propellane chemistry, and for further developments in the synthesis of methylenecyclobutanes based on propellane strain release.

18.
Exp Eye Res ; 238: 109715, 2024 01.
Article in English | MEDLINE | ID: mdl-37951338

ABSTRACT

This study aimed to examine the intraocular tolerability of the epidermal growth factor receptor antibody cetuximab, when applied intravitreally, and its effect on axial elongation. Guinea pigs aged 2-3 weeks were subjected to bilateral plano glasses and bilateral lens-induced myopization (LIM) as a single procedure for group I (n = 8) and group II (n = 8), respectively. In the animals of group III (n = 8), group IV (n = 8), and group V (n = 8), the right eyes of the animals, in addition to LIM, received four weekly intravitreal injections of cetuximab (Erbitux®) in doses of 6.25 µg, 12.5 µg, and 25 µg, respectively. As controls, the left eyes, in addition to LIM, received corresponding intraocular injections of phosphate-buffered saline. The animals underwent regular ophthalmoscopic examinations and biometry for axial length measurements. With increasing doses of cetuximab, the inter-eye difference in axial elongation (at study end, left eyes minus right eyes) were significantly the smallest in group I (0.00 ± 0.02 mm) and group II (-0.01 ± 0.02 mm), they were larger in group III (0.04 ± 0.04 mm) and group IV (0.10 ± 0.03 mm), and they were the largest in group V (0.11 ± 0.01 mm). The inter-eye difference in axial elongation enlarged (P < 0.001) with the number of injections applied. Retinal thickness at the posterior pole (right eyes) was significantly thicker in group V than in group II (P < 0.01). The density of apoptotic cells (visualized by TUNEL-staining) did not vary significantly between any of the groups (all P > 0.05). The results suggest that intravitreal injections of cetuximab in young guinea pigs with LIM resulted in a reduction in axial elongation in a dose-dependent and number of treatment-dependent manner. Intraocular toxic effects, such as intraocular inflammation, retinal thinning, or an increased density of apoptotic cells in the retina, were not observed in association with the intravitreally applied cetuximab.


Subject(s)
Lens, Crystalline , Myopia , Guinea Pigs , Animals , Myopia/metabolism , Cetuximab/toxicity , Cetuximab/metabolism , Retina/metabolism , Lens, Crystalline/metabolism , Injections, Intraocular , Disease Models, Animal
19.
Circ Res ; 130(5): 728-740, 2022 03 04.
Article in English | MEDLINE | ID: mdl-35135328

ABSTRACT

BACKGROUND: Marfan syndrome (MFS) is associated with TGF (transforming growth factor) ß-stimulated ERK (extracellular signal-regulated kinase) activity in vascular smooth muscle cells (VSMCs), which adopt a mixed synthetic/contractile phenotype. In VSMCs, TGFß induces IL (interleukin) 11) that stimulates ERK-dependent secretion of collagens and MMPs (matrix metalloproteinases). Here, we examined the role of IL11 in the MFS aorta. METHODS: We used echocardiography, histology, immunostaining, and biochemical methods to study aortic anatomy, physiology, and molecular endophenotypes in Fbn1C1041G/+ mice, an established murine model of MFS (mMFS). mMFS mice were crossed to an IL11-tagged EGFP (enhanced green fluorescent protein; Il11EGFP/+) reporter strain or to a strain deleted for the IL11 receptor (Il11ra1-/-). In therapeutic studies, mMFS were administered an X209 (neutralizing antibody against IL11RA [IL11 receptor subunit alpha]) or IgG for 20 weeks and imaged longitudinally. RESULTS: IL11 mRNA and protein were elevated in the aortas of mMFS mice, as compared to controls. mMFS mice crossed to Il11EGFP/+ mice had increased IL11 expression in VSMCs, notably in the aortic root and ascending aorta. As compared to the mMFS parental strain, double mutant mMFS:Il11ra1-/- mice had reduced aortic dilatation and exhibited lesser fibrosis, inflammation, elastin breaks, and VSMC loss, which was associated with reduced aortic COL1A1 (collagen type I alpha 1 chain), IL11, MMP2/9, and phospho-ERK expression. To explore therapeutic targeting of IL11 signaling in MFS, we administered either a neutralizing antibody against IL11RA (X209) or an IgG control. After 20 weeks of antibody administration, as compared to IgG, mMFS mice receiving X209 had reduced thoracic and abdominal aortic dilation as well as lesser fibrosis, inflammation, elastin breaks, and VSMC loss. By immunoblotting, X209 was shown to reduce aortic COL1A1, IL11, MMP2/9, and phospho-ERK expression. CONCLUSIONS: In MFS, IL11 is upregulated in aortic VSMCs to cause ERK-related thoracic aortic dilatation, inflammation, and fibrosis. Therapeutic inhibition of IL11, imminent in clinical trials, might be considered as a new approach in MFS.


Subject(s)
Aortic Diseases , Marfan Syndrome , Animals , Antibodies, Neutralizing/metabolism , Antibodies, Neutralizing/pharmacology , Aorta/metabolism , Aortic Diseases/pathology , Disease Models, Animal , Elastin/metabolism , Fibrosis , Immunoglobulin G/metabolism , Inflammation/metabolism , Interleukin-11/metabolism , Interleukin-11 Receptor alpha Subunit , Marfan Syndrome/complications , Marfan Syndrome/genetics , Matrix Metalloproteinase 2/metabolism , Mice , Muscle, Smooth, Vascular/metabolism , Receptors, Interleukin-11/metabolism , Transforming Growth Factor beta/metabolism
20.
Arterioscler Thromb Vasc Biol ; 43(5): 739-754, 2023 05.
Article in English | MEDLINE | ID: mdl-36924234

ABSTRACT

BACKGROUND: Marfan Syndrome (MFS) is an inherited connective tissue disorder caused by mutations in the FBN1 (fibrillin-1) gene. Lung abnormalities are common in MFS, but their pathogenesis is poorly understood. IL11 (interleukin-11) causes aortic disease in a mouse model of MFS and was studied here in the lung. METHODS: We examined histological and molecular phenotypes in the lungs of Fbn1C1041G/+ mice (mouse model of Marfan Syndrome [mMFS]), an established mouse model of MFS. To identify IL11-expressing cells, we used immunohistochemistry on lungs of 4- and 16-week-old Fbn1C1041G/+:Il11EGFP/+ reporter mice. We studied the effects of IL11 inhibition by RT-qPCR, immunoblots and histopathology in lungs from genetic or pharmacologic models: (1) 16-week-old IL11 receptor (IL11RA) knockout mMFS mice (Fbn1C1041G/+:Il11ra1-/- mice) and (2) in mMFS mice administered IgG control or interleukin-11 receptor antibodies twice weekly from 4 to 24 weeks of age. RESULTS: mMFS lungs showed progressive loss and enlargement of distal airspaces associated with increased proinflammatory and profibrotic gene expression as well as matrix metalloproteinases 2, 9, and 12. IL11 was increased in mMFS lungs and localized to smooth muscle and endothelial cells in young mMFS mice in the Fbn1C1041G/+:Il11EGFP/+ reporter strain and in fibroblasts, in older mice. In mMFS mice, genetic (Fbn1C1041G/+:Il11ra1-/-) or pharmacologic (anti-interleukin-11 receptor) inhibition of IL11 signaling reduced lung emphysema, fibrosis, and inflammation. This protective effect was associated with reduced pathogenic ERK1/2 signaling and lower metalloproteinase 2, 9, and 12 expression. CONCLUSIONS: IL11 causes lung disease in mMFS. This reveals a shared IL11-driven disease mechanism in lung and aorta in MFS and suggests inhibition of IL11 signaling as a holistic approach for treating multiorgan morbidity in MFS.


Subject(s)
Interleukin-11 , Marfan Syndrome , Pulmonary Emphysema , Animals , Mice , Disease Models, Animal , Endothelial Cells/metabolism , Fibrillin-1/genetics , Interleukin-11/genetics , Interleukin-11 Receptor alpha Subunit , Marfan Syndrome/complications , Marfan Syndrome/genetics , Marfan Syndrome/pathology , Matrix Metalloproteinase 2/genetics , Mice, Knockout , Pulmonary Emphysema/complications , Pulmonary Emphysema/genetics
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