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1.
Chemistry ; 30(31): e202400398, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38549365

RESUMO

Molecules with curved architecture can exhibit unique optoelectronic properties due to the concave-convex π-surface. However, synthesizing negatively curved saddle-shaped aromatic systems has been challenging due to the internal structural strain. Herein, we report the facile synthesis of two polyhexagonal molecular systems, 1 and 2, with saddle shape geometry by judiciously varying the aromatic moiety, avoiding the harsh synthetic methods as that of heptagonal aromatic saddle systems. The unique geometry preferences of B, N, and S furnish suitable curvature to the molecules, featuring saddle shape. The saddle geometry also enables them to interact with fullerene C60 , and the supramolecular interactions of fullerene C60 with 1 and 2 modify their optoelectronic properties. Crystal structure analysis reveals that 1, with a small π-surface, forms a double columnar array of fullerenes in the solid state. In contrast, 2 with a large π-surface produces a supramolecular capsule entrapping two discrete fullerenes. The intermolecular interactions between B, N, S, and the aryl-π surface of the host and C60 guest are the stabilizing factors for creating these supramolecular structures. Comprehensive computational, optical, and Raman spectroscopic studies establish the charge transfer interactions between B-N doped heterocycle host and fullerene C60 guest.

2.
Chemistry ; 30(17): e202304219, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38155424

RESUMO

Herein, we report the design, synthesis, structure, and electrochemical study of doubly ßC-B-N fused Ni(II) porphyrins (1-trans, 1-cis, 2-trans, and 2-cis). These compounds have been synthesized from A2B2 type dipyridyl Ni(II) porphyrins (Ar=Ph for 1 a; Ar=C6F5 for 2 a) via Lewis base-directed electrophilic aromatic borylation reactions. The solution state structures of these compounds have been established using 1H NMR, 11B NMR, 1H-1H COSY, 1H-13C HSQC, and 19F-13C HSQC NMR techniques. Single crystal X-ray analysis have revealed that 1-trans, 1-cis, and 2-trans adopt ruffled conformations, with alternate meso-carbons on the opposite sides of the mean porphyrin plane. The Soret bands in the absorption spectra of the B-N fused molecules are ~40 nm redshifted compared to unfused Ni(II) porphyrin precursors. The B-N fusion have diminished the redox potential of fused porphyrins. Although 1-trans and 1-cis, show four oxidation processes, 2-trans and 2-cis show only three oxidation processes. DFT studies have revealed that the tetrahedral geometry of the boron has induced a twist in the π-conjugation, which destabilizes the HOMO and stabilizes the LUMO in 1-trans, 1-cis, 2-trans, and 2-cis.

3.
Cell Mol Life Sci ; 79(2): 93, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35075545

RESUMO

Arterial hypertension causes left ventricular hypertrophy leading to dilated cardiomyopathy. Following compensatory cardiomyocyte hypertrophy, cardiac dysfunction develops due to loss of cardiomyocytes preceded or paralleled by cardiac fibrosis. Zyxin acts as a mechanotransducer in vascular cells that may promote cardiomyocyte survival. Here, we analyzed cardiac function during experimental hypertension in zyxin knockout (KO) mice. In zyxin KO mice, made hypertensive by way of deoxycorticosterone acetate (DOCA)-salt treatment telemetry recording showed an attenuated rise in systolic blood pressure. Echocardiography indicated a systolic dysfunction, and isolated working heart measurements showed a decrease in systolic elastance. Hearts from hypertensive zyxin KO mice revealed increased apoptosis, fibrosis and an upregulation of active focal adhesion kinase as well as of integrins α5 and ß1. Both interstitial and perivascular fibrosis were even more pronounced in zyxin KO mice exposed to angiotensin II instead of DOCA-salt. Stretched microvascular endothelial cells may release collagen 1α2 and TGF-ß, which is characteristic for the transition to an intermediate mesenchymal phenotype, and thus spur the transformation of cardiac fibroblasts to myofibroblasts resulting in excessive scar tissue formation in the heart of hypertensive zyxin KO mice. While zyxin KO mice per se do not reveal a cardiac phenotype, this is unmasked upon induction of hypertension and owing to enhanced cardiomyocyte apoptosis and excessive fibrosis causes cardiac dysfunction. Zyxin may thus be important for the maintenance of cardiac function in spite of hypertension.


Assuntos
Angiotensina II/toxicidade , Cardiomegalia/prevenção & controle , Fibrose/prevenção & controle , Hipertensão/complicações , Miócitos Cardíacos/citologia , Zixina/fisiologia , Animais , Apoptose , Pressão Sanguínea , Cardiomegalia/etiologia , Cardiomegalia/patologia , Fibrose/etiologia , Fibrose/patologia , Hipertensão/induzido quimicamente , Hipertensão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/metabolismo
4.
Biochem J ; 479(9): 1007-1030, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35470373

RESUMO

Human Complement Receptor 1 (HuCR1) is a potent membrane-bound regulator of complement both in vitro and in vivo, acting via interaction with its ligands C3b and C4b. Soluble versions of HuCR1 have been described such as TP10, the recombinant full-length extracellular domain, and more recently CSL040, a truncated version lacking the C-terminal long homologous repeat domain D (LHR-D). However, the role of N-linked glycosylation in determining its pharmacokinetic (PK) and pharmacodynamic (PD) properties is only partly understood. We demonstrated a relationship between the asialo-N-glycan levels of CSL040 and its PK/PD properties in rats and non-human primates (NHPs), using recombinant CSL040 preparations with varying asialo-N-glycan levels. The clearance mechanism likely involves the asialoglycoprotein receptor (ASGR), as clearance of CSL040 with a high proportion of asialo-N-glycans was attenuated in vivo by co-administration of rats with asialofetuin, which saturates the ASGR. Biodistribution studies also showed CSL040 localization to the liver following systemic administration. Our studies uncovered differential PD effects by CSL040 on complement pathways, with extended inhibition in both rats and NHPs of the alternative pathway compared with the classical and lectin pathways that were not correlated with its PK profile. Further studies showed that this effect was dose dependent and observed with both CSL040 and the full-length extracellular domain of HuCR1. Taken together, our data suggests that sialylation optimization is an important consideration for developing HuCR1-based therapeutic candidates such as CSL040 with improved PK properties and shows that CSL040 has superior PK/PD responses compared with full-length soluble HuCR1.


Assuntos
Lectinas , Polissacarídeos , Animais , Complemento C3b/metabolismo , Complemento C4b/metabolismo , Glicosilação , Lectinas/metabolismo , Ratos , Receptores de Complemento/metabolismo , Receptores de Complemento 3b/metabolismo , Distribuição Tecidual
5.
Am J Physiol Lung Cell Mol Physiol ; 322(2): L273-L282, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34936510

RESUMO

Mouse models of acute lung injury (ALI) have been instrumental for studies of the biological underpinnings of lung inflammation and permeability, but murine models of sepsis generate minimal lung injury. Our goal was to create a murine sepsis model of ALI that reflects the inflammation, lung edema, histological abnormalities, and physiological dysfunction that characterize ALI. Using a cecal slurry (CS) model of polymicrobial abdominal sepsis and exposure to hyperoxia (95%), we systematically varied the timing and dose of the CS injection, fluids and antibiotics, and dose of hyperoxia. We found that CS alone had a high mortality rate that was improved with the addition of antibiotics and fluids. Despite this, we did not see evidence of ALI as measured by bronchoalveolar lavage (BAL) cell count, total protein, C-X-C motif chemokine ligand 1 (CXCL-1) or by lung wet:dry weight ratio. Addition of hyperoxia [95% fraction of inspired oxygen ([Formula: see text])] to CS immediately after CS injection increased BAL cell counts, CXCL-1, and lung wet:dry weight ratio but was associated with 40% mortality. Splitting the hyperoxia treatment into two 12-h exposures (0-12 h and 24-36 h) after CS injection increased survival to 75% and caused significant lung injury compared with CS alone as measured by increased BAL total cell count (92,500 vs. 240,000, P = 0.0004), BAL protein (71 vs. 103 µg/mL, P = 0.0030), and lung wet:dry weight ratio (4.5 vs. 5.5, P = 0.0005), and compared with sham as measured by increased BAL CXCL-1 (20 vs. 2,372 pg/mL, P < 0.0001) and histological lung injury score (1.9 vs. 4.2, P = 0.0077). In addition, our final model showed evidence of lung epithelial [increased BAL and plasma receptor for advanced glycation end products (RAGE)] and endothelial (increased Syndecan-1 and sulfated glycosaminoglycans) injury. In conclusion, we have developed a clinically relevant mouse model of sepsis-induced ALI using intraperitoneal injection of CS, antibiotics and fluids, and hyperoxia. This clinically relevant model can be used for future studies of sepsis-induced ALI.


Assuntos
Lesão Pulmonar Aguda , Hiperóxia , Sepse , Lesão Pulmonar Aguda/patologia , Animais , Antibacterianos/efeitos adversos , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Hiperóxia/complicações , Hiperóxia/patologia , Inflamação/patologia , Pulmão/metabolismo , Camundongos , Permeabilidade , Sepse/patologia
6.
Nano Lett ; 20(1): 553-558, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31771332

RESUMO

The magnetic properties in two-dimensional van der Waals materials depend sensitively on structure. CrI3, as an example, has been recently demonstrated to exhibit distinct magnetic properties depending on the layer thickness and stacking order. Bulk CrI3 is ferromagnetic (FM) with a Curie temperature of 61 K and a rhombohedral layer stacking, whereas few-layer CrI3 has a layered antiferromagnetic (AFM) phase with a lower ordering temperature of 45 K and a monoclinic stacking. In this work, we use cryogenic magnetic force microscopy to investigate CrI3 flakes in the intermediate thickness range (25-200 nm) and find that the two types of magnetic orders, hence the stacking orders, can coexist in the same flake with a layer of ∼13 nm at each surface being in the layered AFM phase similar to few-layer CrI3 and the rest in the bulk FM phase. The switching of the bulk moment proceeds through a remnant state with nearly compensated magnetic moment along the c-axis, indicating formation of c-axis domains allowed by a weak interlayer coupling strength in the rhombohedral phase. Our results provide a comprehensive picture on the magnetism in CrI3 and point to the possibility of engineering magnetic heterostructures within the same material.

7.
Biomacromolecules ; 20(5): 1889-1898, 2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-30978285

RESUMO

A biocompatible hydrogel containing a hexapeptide as a key unit has been designed and fabricated. Our design construct comprises a ß-sheet-rich short hexapeptide in the center with a hydrophobic long chain and hydrophilic triple lysine unit attached at the N- and C-terminals, respectively. Thus, it is this amphiphilic nature of the molecule that facilitates gelation. It can capture solvent molecules in the three-dimensional cross-linked fibrillar networks. The amphiphilic character of the construct has been modulated to produce an excellent biocompatible soft material for the inhibition of bacterial growth by rupturing the bacterial cell membrane. This hydrogel is also stable against enzymatic degradation (proteinase K) and, most importantly, offers a biocompatible environment for the growth of normal mammalian cells due to its noncytotoxic nature as observed through the cell viability assay. From the hemolytic assay, the morphology of the human red blood cells is found to be almost intact, which suggests that the hydrogel can be used in biomedical applications. Thus, this newly designed antibacterial hydrogel can be used as both an antibacterial biomaterial and a biocompatible scaffold for mammalian cell culture.


Assuntos
Antibacterianos/química , Hidrogéis/química , Lipoproteínas/química , Oligopeptídeos/química , Antibacterianos/efeitos adversos , Antibacterianos/farmacologia , Linhagem Celular , Células Cultivadas , Eritrócitos/efeitos dos fármacos , Hemólise , Humanos , Hidrogéis/efeitos adversos , Hidrogéis/farmacologia , Interações Hidrofóbicas e Hidrofílicas , Lisina/análogos & derivados , Conformação Proteica em Folha beta , Staphylococcus aureus/efeitos dos fármacos
8.
Chin J Traumatol ; 22(3): 138-141, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31056468

RESUMO

PURPOSE: Pelvic fractures are severe injuries and are often associated with multiple system injuries, exacerbating the overall outcome. In India, the incidence of pelvic fractures is on a rise due to suboptimal roads and traffics but related literature regarding the overall epidemiology of these injuries is scarce and scanty. Our aim was to study the epidemiology of patients admitted with pelvic fractures at a level 1 trauma centre in India. METHODS: A 16-month (between September 2015 and December 2016) prospective observational study was carried out on trauma patients with pelvic fractures at a level 1 trauma centre of a tertiary care hospital. Demography of patients, mechanism of injuries and complications were recorded prospectively. RESULTS: We observed 75 patients who presented with pelvic fractures, where 56 were males and 19 were females. Mean age of the study population was 37.57 years. Road traffic accidents were the most common mode of injuries. Lateral compression injuries were the most common pattern. Associated injuries frequently encountered were lower extremities and acetabulum fractures, blunt abdominal trauma, urogenital injuries and head injuries. Out of the 75 patients, 52 were treated surgically and 23 were managed by conservative methods. Associated injuries of the extremities, head, abdomen and urogenital system indicated a longer hospital stay. CONCLUSION: Pelvic fractures, although belong to a relatively rare trauma subset, cause a high morbidity and mortality with considerable burden on the economy. Proper road safety training and driving etiquettes along with its strict implementation in true sense and spirit are the need of the hour.


Assuntos
Fraturas Ósseas/epidemiologia , Ossos Pélvicos/lesões , Acidentes de Trânsito/prevenção & controle , Acidentes de Trânsito/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Efeitos Psicossociais da Doença , Feminino , Fraturas Ósseas/economia , Fraturas Ósseas/mortalidade , Humanos , Incidência , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Centros de Atenção Terciária/estatística & dados numéricos , Fatores de Tempo , Adulto Jovem
9.
Drug Dev Res ; 79(3): 111-118, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29380405

RESUMO

Preclinical Research & Development Gemcitabine, a nucleoside analog, is a well-known chemotherapeutic drug that is used either alone or with other agents to treat a wide variety of cancers. The aim of the present work was to evaluate the potential of 68 Ga-labeled gemcitabine for its application in positron emission tomography (PET) imaging of tumorous lesions. Gemcitabine was coupled with p-NCS-benzyl-DOTA in order to facilitate radiolabeling with 68 Ga. The gemcitabine-p-NCS-benzyl-DOTA was radiolabeled with 68 Ga, obtained from a 68 Ge/68 Ga radionuclide generator. The radiolabeled product was characterized by high performance liquid chromatography (HPLC) and its tumor specificity was evaluated by biodistribution studies in Swiss mice bearing fibrosarcoma tumors. Preliminary bioevaluation study showed good tumor uptake within 1 hr post-administration [2.5% Injected Activity (IA) per g of tumor] with rapid renal clearance (>90% IA) and a high tumor to muscle ratio. 68 Ga-gemcitabine may have potential as a PET agent for tumor imaging.


Assuntos
Antimetabólitos Antineoplásicos , Desoxicitidina/análogos & derivados , Radioisótopos de Gálio , Animais , Antimetabólitos Antineoplásicos/química , Antimetabólitos Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Desoxicitidina/química , Desoxicitidina/farmacocinética , Estabilidade de Medicamentos , Compostos Heterocíclicos/administração & dosagem , Compostos Heterocíclicos/química , Humanos , Masculino , Camundongos , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Tomografia por Emissão de Pósitrons , Soro/química , Distribuição Tecidual , Gencitabina
10.
Proc Natl Acad Sci U S A ; 110(42): 16898-903, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24082093

RESUMO

Despite their abundance and multiple functions in a variety of organ systems, the function and signaling mechanisms of adhesion G protein-coupled receptors (GPCRs) are poorly understood. Adhesion GPCRs possess large N termini containing various functional domains. In addition, many of them are autoproteolytically cleaved at their GPS sites into an N-terminal fragment (NTF) and C-terminal fragment. Here we demonstrate that Gpr126 is expressed in the endocardium during early mouse heart development. Gpr126 knockout in mice and knockdown in zebrafish caused hypotrabeculation and affected mitochondrial function. Ectopic expression of Gpr126-NTF that lacks the GPS motif (NTF(ΔGPS)) in zebrafish rescued the trabeculation but not the previously described myelination phenotype in the peripheral nervous system. These data support a model in which the NTF of Gpr126, in contrast to the C-terminal fragment, plays an important role in heart development. Collectively, our analysis provides a unique example of the versatile function and signaling properties of adhesion GPCRs in vertebrates.


Assuntos
Endocárdio/embriologia , Mitocôndrias Cardíacas/metabolismo , Modelos Biológicos , Receptores Acoplados a Proteínas G/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Animais , Endocárdio/citologia , Camundongos , Camundongos Knockout , Mitocôndrias Cardíacas/genética , Especificidade de Órgãos/fisiologia , Estrutura Terciária de Proteína , Receptores Acoplados a Proteínas G/genética , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
11.
Langmuir ; 30(6): 1677-85, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24460010

RESUMO

We report here the gelation behavior of two novel L-cysteine-based amphiphiles bearing a poly(ethylene glycol) tail. The amphiphiles were found to form transparent organogels in both apolar and aprotic polar solvents at reasonably low concentrations. In chloroform, dichloromethane, and benzene solvents, the organogels are formed at room temperature without the requirement of heating-cooling cycle due to strong hydrogen-bonding interaction between gelator molecules. The swelling kinetics, however, becomes faster on heating. Unlike most organogels of low-molecular-mass gelators, these organogels do not exhibit a gel-to-sol transition on heating but instead become rigid when heated. Surprisingly, in polar solvents, the gelation required a heating-cooling cycle, and the sol-to-gel transition was found to be reversible. The gelation abilities of the amphiphiles were correlated with the hydrogen-bonding parameters of the solvents. Intermolecular H-bonding interaction was found to be the major driving force for the organogelation. The morphology of the organogels was investigated by the use of optical as well as electron microscopy and was found to be dependent on the nature of solvent. The mechanical strengths of the organogels were studied by rheological measurements.


Assuntos
Cisteína/química , Polietilenoglicóis/química , Tensoativos/química , Benzeno , Clorofórmio , Géis , Temperatura Alta , Ligação de Hidrogênio , Cloreto de Metileno , Transição de Fase , Reologia , Solventes
12.
Artigo em Inglês | MEDLINE | ID: mdl-38600813

RESUMO

We investigated low-frequency current fluctuations, i.e., electronic noise, in FePS3 van der Waals layered antiferromagnetic semiconductor. The noise measurements have been used as noise spectroscopy for advanced materials characterization of the charge carrier dynamics affected by spin ordering and trapping states. Owing to the high resistivity of the material, we conducted measurements on vertical device configuration. The measured noise spectra reveal pronounced Lorentzian peaks of two different origins. One peak is observed only near the Néel temperature, and it is attributed to the corresponding magnetic phase transition. The second Lorentzian peak, visible in the entire measured temperature range, has characteristics of the trap-assisted generation-recombination processes similar to those in conventional semiconductors but shows a clear effect of the spin order reconfiguration near the Néel temperature. The obtained results contribute to understanding the electron and spin dynamics in this type of antiferromagnetic semiconductors and demonstrate the potential of electronic noise spectroscopy for advanced materials characterization.

13.
J Phys Chem Lett ; 15(11): 3078-3088, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38467015

RESUMO

A biomimetic cell-based carrier system based on monocyte membranes and liposomes has been designed to create a hybrid "Monocyte-LP" which inherits the surface antigens of the monocytes along with the drug encapsulation property of the liposome. Förster resonance energy transfer (FRET) and polarization gated anisotropy measurements show the stiffness of the vesicles obtained from monocyte membranes (Mons), phosphatidylcholine membranes (LP), and Monocyte-LP to follow an increasing order of Mons > Monocyte-LP > LP. The dynamics of interface bound water molecules plays a key role in the elasticity of the vesicles, which in turn imparts higher delivery efficacy to the hybrid Monocyte-LP for a model anticancer drug doxorubicin than the other two vesicles, indicating a critical balance between flexibility and rigidity for an efficient cellular uptake. The present work provides insight on the influence of elasticity of delivery vehicles for enhanced drug delivery.


Assuntos
Antineoplásicos , Lipossomos , Lipossomos/metabolismo , Monócitos/metabolismo , Doxorrubicina , Sistemas de Liberação de Medicamentos
14.
ACS Chem Neurosci ; 14(4): 773-786, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36728363

RESUMO

The misfolding of amyloid beta (Aß) peptides into Aß fibrillary aggregates is a major hallmark of Alzheimer's disease (AD), which responsible for the excess production of hydrogen peroxide (H2O2), a prominent reactive oxygen species (ROS) from the molecular oxygen (O2) by the reduction of the Aß-Cu(I) complex. The excessive production of H2O2 causes oxidative stress and inflammation in the AD brain. Here, we have designed and developed a dual functionalized molecule VBD by using π-conjugation (C═C) in the backbone structure. In the presence of H2O2, the VBD can turn into fluorescent probe VBD-1 by cleaving of the selective boronate ester group. The fluorescent probe VBD-1 can undergo intramolecular charge transfer transition (ICT) by a π-conjugative system, and as a result, its emission increases from the yellow (532 nm) to red (590 nm) region. The fluorescence intensity of VBD-1 increases by 3.5-fold upon binding with Aß fibrillary aggregates with a high affinity (Kd = 143 ± 12 nM). Finally, the VBD reduces the cellular toxic H2O2 as proven by the CCA assay and DCFDA assay and the binding affinity of VBD-1 was confirmed by using in vitro histological staining in 8- and 18-month-old triple transgenic AD (3xTg-AD) mice brain slices.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peptídeos beta-Amiloides/metabolismo , Corantes Fluorescentes/metabolismo , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/química , Encéfalo/metabolismo , Benzotiazóis/metabolismo , Amiloide/metabolismo , Camundongos Transgênicos
15.
ACS Chem Neurosci ; 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37014355

RESUMO

The overproduction and deposition of the amyloid-ß (Aß) aggregates are accountable for the genesis and development of the neurologic disorder Alzheimer's disease (AD). Effective medications and detection agents for AD are still deficient. General challenges for the diagnosis of Aß aggregates in the AD brain are (i) crossing the blood-brain barrier (BBB) and (ii) selectivity to Aß species with (iii) emission maxima in the 500-750 nm region. Thioflavin-T (ThT) is the most used fluorescent probe for imaging Aß fibril aggregates. However, because of the poor BBB crossing (log P = -0.14) and short emission wavelength (482 nm) after binding with Aß fibrils, ThT can be limited to in vitro use only. Herein, we have developed Aß deposit-recognizing fluorescent probes (ARs) with a D-π-A architecture and a longer emission wavelength after binding with Aß species. Among the newly designed probes, AR-14 showed an admirable fluorescence emission (>600 nm) change after binding with soluble Aß oligomers (2.3-fold) and insoluble Aß fibril aggregates (4.5-fold) with high affinities Kd = 24.25 ± 4.10 nM; Ka = (4.123 ± 0.69) × 107 M-1 for fibrils; Kd = 32.58 ± 4.89 nM; and Ka = (3.069 ± 0.46) × 107 M-1 for oligomers with high quantum yield, molecular weight of <500 Da, reasonable log P = 1.77, stability in serum, and nontoxicity, and it can cross the BBB efficiently. The binding affinity of AR-14 toward Aß species is proved by fluorescence binding studies and fluorescent staining of 18-month-old triple-transgenic (3xTg) mouse brain sections. In summary, the fluorescent probe AR-14 is efficient and has an admirable quality for the detection of soluble and insoluble Aß deposits in vitro and in vivo.

16.
Cells ; 12(18)2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37759537

RESUMO

In arteries and arterioles, a chronic increase in blood pressure raises wall tension. This continuous biomechanical strain causes a change in gene expression in vascular smooth muscle cells (VSMCs) that may lead to pathological changes. Here we have characterised the functional properties of lipoma-preferred partner (LPP), a Lin11-Isl1-Mec3 (LIM)-domain protein, which is most closely related to the mechanotransducer zyxin but selectively expressed by smooth muscle cells, including VSMCs in adult mice. VSMCs isolated from the aorta of LPP knockout (LPP-KO) mice displayed a higher rate of proliferation than their wildtype (WT) counterparts, and when cultured as three-dimensional spheroids, they revealed a higher expression of the proliferation marker Ki 67 and showed greater invasion into a collagen gel. Accordingly, the gelatinase activity was increased in LPP-KO but not WT spheroids. The LPP-KO spheroids adhering to the collagen gel responded with decreased contraction to potassium chloride. The relaxation response to caffeine and norepinephrine was also smaller in the LPP-KO spheroids than in their WT counterparts. The overexpression of zyxin in LPP-KO VSMCs resulted in a reversal to a more quiescent differentiated phenotype. In native VSMCs, i.e., in isolated perfused segments of the mesenteric artery (MA), the contractile responses of LPP-KO segments to potassium chloride, phenylephrine or endothelin-1 did not vary from those in isolated perfused WT segments. In contrast, the myogenic response of LPP-KO MA segments was significantly attenuated while zyxin-deficient MA segments displayed a normal myogenic response. We propose that LPP, which we found to be expressed solely in the medial layer of different arteries from adult mice, may play an important role in controlling the quiescent contractile phenotype of VSMCs.


Assuntos
Lipoma , Músculo Liso Vascular , Camundongos , Animais , Zixina/metabolismo , Músculo Liso Vascular/metabolismo , Cloreto de Potássio/metabolismo , Colágeno/metabolismo , Fatores de Transcrição/metabolismo , Miócitos de Músculo Liso/metabolismo , Lipoma/metabolismo , Lipoma/patologia
17.
Neurooncol Adv ; 5(1): vdad088, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37554225

RESUMO

Background: Myeloid-derived suppressor cells (MDSCs) are critical regulators of immunosuppression and radioresistance in glioblastoma (GBM). The primary objective of this pilot phase Ib study was to validate the on-target effect of tadalafil on inhibiting MDSCs in peripheral blood and its safety when combined with chemoradiotherapy in GBM patients. Methods: Patients with newly diagnosed IDH-wild-type GBM received radiation therapy (RT) and temozolomide (TMZ) combined with oral tadalafil for 2 months. A historical cohort of 12 GBM patients treated with RT and TMZ was used as the comparison group. The ratio of MDSCs, T cells, and cytokines at week 6 of RT compared to baseline were analyzed using flow cytometry. Progression-free survival (PFS) and overall survival (OS) were estimated by the Kaplan-Meier method. Results: Tadalafil was well tolerated with no dose-limiting toxicity among 16 evaluable patients. The tadalafil cohort had a significantly lower ratio of circulating MDSCs than the control: granulocytic-MDSCs (mean 0.78 versus 3.21, respectively, P = 0.01) and monocytic-MDSCs (1.02 versus 1.96, respectively, P = 0.006). Tadalafil increased the CD8 ratio compared to the control (1.99 versus 0.70, respectively, P < 0.001), especially the PD-1-CD8 T cells expressing Ki-67, CD38, HLA-DR, CD28, and granzyme B. Proinflammatory cytokine IL-1ß was also significantly increased after tadalafil compared to the control. The tadalafil cohort did not have significantly different PFS and OS than the historical control. Conclusions: Concurrent tadalafil is well tolerated during chemoradiotherapy for GBM. Tadalafil is associated with a reduction of peripheral MDSCs after chemoradiotherapy and increased CD8 T-cell proliferation and activation.

18.
Sci Transl Med ; 15(680): eabn6758, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36696484

RESUMO

Severe and prolonged lymphopenia frequently occurs in patients with glioblastoma after standard chemoradiotherapy and has been associated with worse survival, but its underlying biological mechanism is not well understood. To address this, we performed a correlative study in which we collected and analyzed peripheral blood of patients with glioblastoma (n = 20) receiving chemoradiotherapy using genomic and immune monitoring technologies. RNA sequencing analysis of the peripheral blood mononuclear cells (PBMC) showed an elevated concentration of myeloid-derived suppressor cell (MDSC) regulatory genes in patients with lymphopenia when compared with patients without lymphopenia after chemoradiotherapy. Additional analysis including flow cytometry and single-cell RNA sequencing further confirmed increased numbers of circulating MDSC in patients with lymphopenia when compared with patients without lymphopenia after chemoradiotherapy. Preclinical murine models were also established and demonstrated a causal relationship between radiation-induced MDSC and systemic lymphopenia using transfusion and depletion experiments. Pharmacological inhibition of MDSC using an arginase-1 inhibitor (CB1158) or phosphodiesterase-5 inhibitor (tadalafil) during radiation therapy (RT) successfully abrogated radiation-induced lymphopenia and improved survival in the preclinical models. CB1158 and tadalafil are promising drugs in reducing radiation-induced lymphopenia in patients with glioblastoma. These results demonstrate the promise of using these classes of drugs to reduce treatment-related lymphopenia and immunosuppression.


Assuntos
Glioblastoma , Linfopenia , Células Supressoras Mieloides , Humanos , Animais , Camundongos , Glioblastoma/complicações , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Leucócitos Mononucleares , Tadalafila , Linfopenia/etiologia , Quimiorradioterapia/efeitos adversos
19.
J Clin Invest ; 133(15)2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37279067

RESUMO

Patients with cancer who have high serum levels of squamous cell carcinoma antigen 1 (SCCA1, now referred to as SERPINB3) commonly experience treatment resistance and have a poor prognosis. Despite being a clinical biomarker, the modulation of SERPINB3 in tumor immunity is poorly understood. We found positive correlations of SERPINB3 with CXCL1, CXCL8 (CXCL8/9), S100A8, and S100A9 (S100A8/A9) myeloid cell infiltration through RNA-Seq analysis of human primary cervical tumors. Induction of SERPINB3 resulted in increased CXCL1/8 and S100A8/A9 expression, which promoted monocyte and myeloid-derived suppressor cell (MDSC) migration in vitro. In mouse models, Serpinb3a tumors showed increased MDSC and tumor-associated macrophage (TAM) infiltration, contributing to T cell inhibition, and this was further augmented upon radiation. Intratumoral knockdown (KD) of Serpinb3a resulted in tumor growth inhibition and reduced CXCL1 and S100A8/A expression and MDSC and M2 macrophage infiltration. These changes led to enhanced cytotoxic T cell function and sensitized tumors to radiotherapy (RT). We further revealed that SERPINB3 promoted STAT-dependent expression of chemokines, whereby inhibition of STAT activation by ruxolitinib or siRNA abrogated CXCL1/8 and S100A8/ A9 expression in SERPINB3 cells. Patients with elevated pretreatment SCCA levels and high phosphorylated STAT3 (p-STAT3) had increased intratumoral CD11b+ myeloid cells compared with patients with low SCCA levels and p-STAT3, who had improved overall survival after RT. These findings provide a preclinical rationale for targeting SERPINB3 in tumors to counteract immunosuppression and improve the response to RT.


Assuntos
Calgranulina A , Serpinas , Camundongos , Animais , Humanos , Calgranulina A/genética , Calgranulina B/genética , Serpinas/genética , Quimiocinas/metabolismo
20.
Sci Rep ; 12(1): 10772, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35750870

RESUMO

Breast cancer is the most common malignancy in women and is a heterogeneous disease at molecular level. Early detection and specificity are the key prerequisite for the treatment of this deadly cancer. To address these issues attention on the breast cancer specific receptor protein(s) is the most realistic option. Herein estrogen (E) and progesterone (Pg) receptors(R) were considered to design fluorescent molecular probes with possible therapeutic option. We adopted QSAR technique to design a library of benzothiazole-purine hybrid molecules. Molecular docking offers us three screened molecules as most potential. Among these molecules one abbreviated as "CPIB" showed blue fluorescence and detected ER positive cancer cells at 1 nM concentration. At elevated concentration, CPIB induces apoptotic deaths of same cancer cells through targeting intracellular microtubules without affecting normal cells or ER negative cells. CPIB is one of its kind with two-in-one potential of "Detection and Destroy" ability targeting ER positive breast cancer cells.


Assuntos
Neoplasias da Mama , Receptores de Estrogênio , Benzotiazóis/farmacologia , Benzotiazóis/uso terapêutico , Neoplasias da Mama/patologia , Feminino , Corantes Fluorescentes/uso terapêutico , Humanos , Microtúbulos/patologia , Simulação de Acoplamento Molecular , Sondas Moleculares , Purinas/uso terapêutico , Receptores de Estrogênio/genética , Receptores de Progesterona/genética
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