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1.
Angew Chem Int Ed Engl ; : e202416154, 2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39400436

RESUMEN

Multi-resonance thermally activated delayed fluorescence (MR-TADF) molecules have experienced great success in organic light-emitting diodes (OLEDs) owing to their outstanding quantum efficiencies and narrow full width at half-maximums (FWHMs). However, the reverse intersystem crossing (RISC) rates of MR-TADF emitters are usually small, which will lead to relatively long triplet exciton lifetime and severe efficiency roll-off. Here, we report an effective molecular design strategy to introduce multichannel RISC pathways and thus increase RISC rates without compromising the color fidelity and emission efficiency by the "hybridized long-short axis (HLSA)" strategy. The TPA-CN-BN shows a near-unity photoluminescence quantum yield, rapid RISC rate of 1.4 × 105 s-1, narrow FWHM of 23 nm, and small singlet-triplet energy gap (ΔEST) of 0.06 eV in solution. The non-sensitized OLED based on TPA-CN-BN exhibits a narrowband emission with the FWHM of 31 nm, in company with external quantum efficiency (EQE) of 37.9%. Notably, the device exhibits the low efficiency roll-off as the EQEs maintain 34.8% and 21.8% at 100 and 1000 cd m-2, respectively, representing the best performance for single-host OLEDs based on the BCzBN skeleton. This study provides a fresh and promising approach to realize high-performance OLEDs with high color purity and remarkable device efficiency.

2.
Cell Death Dis ; 15(9): 654, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39231945

RESUMEN

Transforming growth factor (TGF)-ß signaling is critical for epithelial-mesenchymal transition (EMT) and colorectal cancer (CRC) metastasis. Disruption of Smad-depednent TGF-ß signaling has been shown in CRC cells. However, TGF-ß receptor remains expressed on CRC cells. Here, we investigated whether the cooperation between tumor-associated N-glycosylation and a glycan-binding protein modulated the TGF-ß-driven signaling and metastasis of CRC. We showed that galectin-8, a galactose-binding lectin, hampered TGF-ß-induced EMT by interacting with the type II TGF-ß receptor and competing with TGF-ß binding. Depletion of galectin-8 promoted the migration of CRC cells by increasing TGF-ß-receptor-mediated RAS and Src signaling, which was attenuated after recombinant galectin-8 treatment. Treatment with recombinant galectin-8 also induces JNK-dependent apoptosis in CRC cells. The anti-migratory effect of galectin-8 depended on ß4-galactosyltransferase-I (B4GALT1), an enzyme involved in N-glycan synthesis. Increased B4GALT1 expression was observed in clinical CRC samples. Depletion of B4GALT1 reduced the metastatic potential of CRC cells. Furthermore, inducible expression of galectin-8 attenuated tumor development and metastasis of CRC cells in an intra-splenic injection model. Our results thus demonstrate that galectin-8 alters non-canonical TGF-ß response in CRC cells and suppresses CRC progression.


Asunto(s)
Movimiento Celular , Neoplasias Colorrectales , Transición Epitelial-Mesenquimal , Galactosiltransferasas , Galectinas , Metástasis de la Neoplasia , Humanos , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/genética , Galectinas/metabolismo , Galectinas/genética , Galactosiltransferasas/metabolismo , Galactosiltransferasas/genética , Transición Epitelial-Mesenquimal/efectos de los fármacos , Animales , Movimiento Celular/efectos de los fármacos , Progresión de la Enfermedad , Línea Celular Tumoral , Transducción de Señal , Ratones , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Ratones Desnudos , Unión Proteica , Apoptosis/efectos de los fármacos , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Ratones Endogámicos BALB C
3.
Semin Immunopathol ; 46(3-4): 6, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39042263

RESUMEN

Galectins, a family of glycan-binding proteins have been shown to bind a wide range of glycans. In the cytoplasm, these glycans can be endogenous (or "self"), originating from damaged endocytic vesicles, or exogenous (or "non-self"), found on the surface of invading microbial pathogens. Galectins can detect these unusual cytosolic exposures to glycans and serve as critical regulators in orchestrating immune responses in innate and adaptive immunity. This review provides an overview of how galectins modulate host cellular responses, such as autophagy, xenophagy, and inflammasome-dependent cell death program, to infection.


Asunto(s)
Autofagia , Galectinas , Inflamasomas , Humanos , Autofagia/inmunología , Galectinas/metabolismo , Galectinas/inmunología , Inflamasomas/metabolismo , Animales , Inmunidad Innata , Interacciones Huésped-Patógeno/inmunología , Transducción de Señal , Inmunidad Adaptativa
4.
Kidney Int ; 106(4): 658-670, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39084257

RESUMEN

IgA nephropathy (IgAN) is the most common type of glomerulonephritis that frequently progresses to kidney failure. However, the molecular pathogenesis underlying IgAN remains largely unknown. Here, we investigated the role of galectin-3 (Gal-3), a galactoside-binding protein in IgAN pathogenesis, and showed that Gal-3 expression by the kidney was significantly enhanced in patients with IgAN. In both TEPC-15 hybridoma-derived IgA-induced, passive, and spontaneous "grouped" ddY IgAN models, Gal-3 expression was clearly increased with disease severity in the glomeruli, peri-glomerular regions, and some kidney tubules. Gal-3 knockout (KO) in the passive IgAN model had significantly improved proteinuria, kidney function and reduced severity of kidney pathology, including neutrophil infiltration and decreased differentiation of Th17 cells from kidney-draining lymph nodes, despite increased percentages of regulatory T cells. Gal-3 KO also inhibited the NLRP3 inflammasome, yet it enhanced autophagy and improved kidney inflammation and fibrosis. Moreover, administration of 6-de-O-sulfated, N-acetylated low-molecular-weight heparin, a competitive Gal-3 binding inhibitor, restored kidney function and improved kidney lesions in passive IgAN mice. Thus, our results suggest that Gal-3 is critically involved in IgAN pathogenesis by activating the NLRP3 inflammasome and promoting Th17 cell differentiation. Hence, targeting Gal-3 action may represent a new therapeutic strategy for treatment of this kidney disease.


Asunto(s)
Modelos Animales de Enfermedad , Galectina 3 , Glomerulonefritis por IGA , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR , Células Th17 , Glomerulonefritis por IGA/patología , Glomerulonefritis por IGA/inmunología , Glomerulonefritis por IGA/metabolismo , Glomerulonefritis por IGA/genética , Animales , Galectina 3/metabolismo , Galectina 3/genética , Galectina 3/antagonistas & inhibidores , Humanos , Células Th17/inmunología , Células Th17/metabolismo , Ratones , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Masculino , Femenino , Inflamasomas/metabolismo , Inflamasomas/inmunología , Autofagia/efectos de los fármacos , Fibrosis , Linfocitos T Reguladores/inmunología , Diferenciación Celular , Galectinas/genética , Galectinas/metabolismo , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Ratones Endogámicos C57BL , Glomérulos Renales/patología , Glomérulos Renales/inmunología , Inmunoglobulina A/metabolismo , Inmunoglobulina A/inmunología
5.
J Clin Invest ; 134(2)2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-37988169

RESUMEN

Alzheimer's disease is characterized by the accumulation of amyloid-ß plaques, aggregation of hyperphosphorylated tau (pTau), and microglia activation. Galectin-3 (Gal3) is a ß-galactoside-binding protein that has been implicated in amyloid pathology. Its role in tauopathy remains enigmatic. Here, we showed that Gal3 was upregulated in the microglia of humans and mice with tauopathy. pTau triggered the release of Gal3 from human induced pluripotent stem cell-derived microglia in both its free and extracellular vesicular-associated (EV-associated) forms. Both forms of Gal3 increased the accumulation of pathogenic tau in recipient cells. Binding of Gal3 to pTau greatly enhanced tau fibrillation. Besides Gal3, pTau was sorted into EVs for transmission. Moreover, pTau markedly enhanced the number of EVs released by iMGL in a Gal3-dependent manner, suggesting a role of Gal3 in biogenesis of EVs. Single-cell RNA-Seq analysis of the hippocampus of a mouse model of tauopathy (THY-Tau22) revealed a group of pathogenic tau-evoked, Gal3-associated microglia with altered cellular machineries implicated in neurodegeneration, including enhanced immune and inflammatory responses. Genetic removal of Gal3 in THY-Tau22 mice suppressed microglia activation, reduced the level of pTau and synaptic loss in neurons, and rescued memory impairment. Collectively, Gal3 is a potential therapeutic target for tauopathy.


Asunto(s)
Galectina 3 , Tauopatías , Proteínas tau , Animales , Humanos , Ratones , Enfermedad de Alzheimer/patología , Modelos Animales de Enfermedad , Galectina 3/genética , Galectina 3/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Ratones Transgénicos , Microglía/patología , Proteínas tau/genética , Proteínas tau/metabolismo , Tauopatías/genética , Tauopatías/metabolismo
6.
ACS Appl Mater Interfaces ; 15(40): 47307-47316, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37750758

RESUMEN

Developing high-efficiency nondoped blue organic light-emitting diodes (OLEDs) with high color purity and low-efficiency roll-off is vital for display and lighting applications. Herein, we developed two asymmetric D-π-A blue emitters, PIAnTP and PyIAnTP, in which triphenylene is first utilized as a functional acceptor. The relatively weak charge transfer (CT) properties, rigid molecular structures, and multiple supramolecular interactions in PIAnTP and PyIAnTP can significantly enhance the fluorescence efficiency and suppress the structural relaxations to obtain a narrowband blue emission. The photophysical experiments and theoretical simulations reveal that they both exhibit a typical hybridized local and charge-transfer (HLCT) excited state and achieve high external quantum efficiency (EQE) via a "hot exciton" channel. As a result, PIAnTP- and PyIAnTP-based nondoped devices realize blue emission at 456 and 464 nm, corresponding to CIE coordinates of (0.16, 0.14) and (0.16, 0.19), narrow full width at half-maximums of 52 and 60 nm, and the high EQEs of 8.36 and 8.69%, respectively. More importantly, the PIAnTP- and PyIAnTP-based nondoped devices show small EQE roll-offs of only 5.9 and 2.4% at 1000 cd m-2, respectively. These results signify an advance in designing a highly efficient blue emitter for nondoped OLEDs.

7.
J Invest Dermatol ; 143(11): 2120-2131.e7, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37207806

RESUMEN

Sebaceous glands (SGs) are holocrine glands that produce sebum, which primarily contains lipids that help to maintain the barrier function of the skin. Dysregulated lipid production contributes to the progression of some diseases characterized by dry skin, including atopic dermatitis. Although the lipid production of SGs has been well-studied, few studies have assessed their role in skin immune responses. We found that SGs and sebocytes expressed IL-4 receptor and produced high levels of T helper 2-associated inflammatory mediators after IL-4 treatment, suggesting immunomodulatory effects. Galectin-12 is a lipogenic factor expressed in sebocytes that affects their differentiation and proliferation. Using galectin-12-knockdown sebocytes, we showed that galectin-12 regulated the immune response in cells exposed to IL-4 and promoted CCL26 expression by upregulating peroxisome proliferator-activated receptor-γ. Moreover, galectin-12 suppressed the expression of endoplasmic reticulum stress-response molecules, and CCL26 upregulation by IL-4 was reversed after sebocyte treatment with inducers of endoplasmic reticulum stress, suggesting that galectin-12 controls IL-4 signaling by suppressing endoplasmic reticulum stress. Using galectin-12-knockout mice, we showed that galectin-12 positively regulated the IL-4-induced enlargement of SGs and the development of an atopic dermatitis-like phenotype. Thus, galectin-12 regulates the skin immune response by promoting peroxisome proliferator-activated receptor-γ expression and suppressing endoplasmic reticulum stress in SGs.

8.
Glycoconj J ; 40(3): 295-303, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37052731

RESUMEN

Sialylation is an important terminal modification of glycoconjugates that mediate diverse functions in physiology and disease. In this review we focus on how altered cell surface sialylation status is sensed by cytosolic galectins when the integrity of intracellular vesicles or organelles is compromised to expose luminal glycans to the cytosolic milieu, and how this impacts galectin-mediated cellular responses. In addition, we discuss the roles of mammalian sialidases on the cell surface, in the organelle lumen and cytosol, and raise the possibility that intracellular glycan processing may be critical in controlling various galectin-mediated responses when cells encounter stress.


Asunto(s)
Galectinas , Polisacáridos , Animales , Galectinas/metabolismo , Citosol/metabolismo , Polisacáridos/metabolismo , Glicoconjugados/metabolismo , Orgánulos , Mamíferos/metabolismo
9.
J Invest Dermatol ; 143(8): 1449-1460, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36868499

RESUMEN

Psoriasis is an IL-23/IL-17-mediated inflammatory autoimmune dermatosis, and UVB may contribute to immunosuppression and ameliorate associated symptoms. One of the pathophysiology underlying UVB therapy is the production of cis-urocanic acid (cis-UCA) by keratinocytes. However, the detailed mechanism is yet to be fully understood. In this study, we found FLG expression and serum cis-UCA levels were significantly lower in patients with psoriasis than in healthy controls. We also noted that cis-UCA application inhibited psoriasiform inflammation through the reduction of Vγ4+ γδT17 cells in murine skin and draining lymph nodes. Meanwhile, CCR6 was downregulated on γδT17 cells, which would suppress the inflammatory reaction at a distal skin site. We revealed that the 5-hydroxytryptamine receptor 2A, the known cis-UCA receptor, was highly expressed on Langerhans cells in the skin. cis-UCA also inhibited IL-23 expression and induced PD-L1 on Langerhans cells, leading to the attenuated proliferation and migration of γδT-cells. Compared to the isotype control, α-PD-L1 treatment in vivo could reverse the antipsoriatic effects of cis-UCA. PD-L1 expression on Langerhans cells was sustained through the cis-UCA-induced mitogen-activated protein kinase/extracellular signal-regulated kinase pathway. These findings uncover the cis-UCA-induced PD-L1-mediated immunosuppression on Langerhans cells, which facilitates the resolution of inflammatory dermatoses.


Asunto(s)
Dermatitis , Psoriasis , Ácido Urocánico , Humanos , Ratones , Animales , Células de Langerhans , Imiquimod/farmacología , Antígeno B7-H1 , Inflamación , Psoriasis/inducido químicamente , Psoriasis/tratamiento farmacológico , Interleucina-23/farmacología , Rayos Ultravioleta
10.
J Biomed Sci ; 30(1): 14, 2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36823664

RESUMEN

BACKGROUND: Influenza is one of the most important viral infections globally. Viral RNA-dependent RNA polymerase (RdRp) consists of the PA, PB1, and PB2 subunits, and the amino acid residues of each subunit are highly conserved among influenza A virus (IAV) strains. Due to the high mutation rate and emergence of drug resistance, new antiviral strategies are needed. Host cell factors are involved in the transcription and replication of influenza virus. Here, we investigated the role of galectin-3, a member of the ß-galactoside-binding animal lectin family, in the life cycle of IAV infection in vitro and in mice. METHODS: We used galectin-3 knockout and wild-type mice and cells to study the intracellular role of galectin-3 in influenza pathogenesis. Body weight and survival time of IAV-infected mice were analyzed, and viral production in mouse macrophages and lung fibroblasts was examined. Overexpression and knockdown of galectin-3 in A549 human lung epithelial cells were exploited to assess viral entry, viral ribonucleoprotein (vRNP) import/export, transcription, replication, virion production, as well as interactions between galectin-3 and viral proteins by immunoblotting, immunofluorescence, co-immunoprecipitation, RT-qPCR, minireplicon, and plaque assays. We also employed recombinant galectin-3 proteins to identify specific step(s) of the viral life cycle that was affected by exogenously added galectin-3 in A549 cells. RESULTS: Galectin-3 levels were increased in the bronchoalveolar lavage fluid and lungs of IAV-infected mice. There was a positive correlation between galectin-3 levels and viral loads. Notably, galectin-3 knockout mice were resistant to IAV infection. Knockdown of galectin-3 significantly reduced the production of viral proteins and virions in A549 cells. While intracellular galectin-3 did not affect viral entry, it increased vRNP nuclear import, RdRp activity, and viral transcription and replication, which were associated with the interaction of galectin-3 with viral PA subunit. Galectin-3 enhanced the interaction between viral PA and PB1 proteins. Moreover, exogenously added recombinant galectin-3 proteins also enhanced viral adsorption and promoted IAV infection in A549 cells. CONCLUSION: We demonstrate that galectin-3 enhances viral infection through increases in vRNP nuclear import and RdRp activity, thereby facilitating viral transcription and replication. Our findings also identify galectin-3 as a potential therapeutic target for influenza.


Asunto(s)
Virus de la Influenza A , Gripe Humana , Animales , Humanos , Ratones , Proteínas Virales/genética , Galectina 3/genética , Galectina 3/metabolismo , Regulación hacia Arriba , Gripe Humana/genética , ARN Viral/metabolismo , Virus de la Influenza A/genética , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo , Replicación Viral/genética
11.
Nat Rev Immunol ; 23(8): 479-494, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36646848

RESUMEN

The galectin family consists of carbohydrate (glycan) binding proteins that are expressed by a wide variety of cells and bind to galactose-containing glycans. Galectins can be located in the nucleus or the cytoplasm, or can be secreted into the extracellular space. They can modulate innate and adaptive immune cells by binding to glycans on the surface of immune cells or intracellularly via carbohydrate-dependent or carbohydrate-independent interactions. Galectins expressed by immune cells can also participate in host responses to infection by directly binding to microorganisms or by modulating antimicrobial functions such as autophagy. Here we explore the diverse ways in which galectins have been shown to impact immunity and discuss the opportunities and challenges in the field.


Asunto(s)
Galectinas , Polisacáridos , Humanos , Galectinas/química , Galectinas/metabolismo , Carbohidratos
12.
PLoS Negl Trop Dis ; 17(1): e0011016, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36595499

RESUMEN

Cytoadherence of Trichomonas vaginalis to human vaginal epithelial cells (hVECs) was previously shown to involve surface lipoglycans and several reputed adhesins on the parasite. Herein, we report some new observations on the host-parasite interactions of adherent versus nonadherent T. vaginalis isolates to hVECs. The binding of the TH17 adherent isolate to hVECs exhibited an initial discrete phase followed by an aggregation phase inhibited by lactose. T. vaginalis infection immediately induced surface expression of galectin-1 and -3, with extracellular amounts in the spent medium initially decreasing and then increasing thereafter over the next 60 min. Extracellular galectin-1 and -3 were detected on the parasite surface but only the TH17 adherent isolate could uptake galectin-3 via the lysosomes. Only the adherent isolate could morphologically transform from the round-up flagellate with numerous transient protrusions into a flat amoeboid form on contact with the solid surface. Cytochalasin D challenge revealed that actin organization was essential to parasite morphogenesis and cytoadherence. Real-time microscopy showed that parasite exploring and anchoring on hVECs via the axostyle may be required for initial cytoadherence. Together, the parasite cytoskeleton behaviors may collaborate with cell surface adhesion molecules for cytoadherence. The nonadherent isolate migrated faster than the adherent isolate, with motility transiently increasing in the presence of hVECs. Meanwhile, differential histone acetylation was detected between the two isolates. Also, TH17 without Mycoplasma symbiosis suggests that symbiont might not determine TH17 innate cytoadherence. Our findings regarding distinctive host-parasite interactions of the isolates may provide novel insights into T. vaginalis infection.


Asunto(s)
Trichomonas vaginalis , Femenino , Humanos , Galectina 1 , Interacciones Huésped-Parásitos , Adhesión Celular , Células Epiteliales/parasitología , Moléculas de Adhesión Celular
13.
Proc Natl Acad Sci U S A ; 120(5): e2207091120, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36689650

RESUMEN

Galectin-4, a member of the galectin family of animal glycan-binding proteins (GBPs), is specifically expressed in gastrointestinal epithelial cells and is known to be able to bind microbes. However, its function in host-gut microbe interactions remains unknown. Here, we show that intracellular galectin-4 in intestinal epithelial cells (IECs) coats cytosolic Salmonella enterica serovar Worthington and induces the formation of bacterial chains and aggregates. Galectin-4 enchains bacteria during their growth by binding to the O-antigen of lipopolysaccharides. Furthermore, the binding of galectin-4 to bacterial surfaces restricts intracellular bacterial motility. Galectin-4 enhances caspase-1 activation and mature IL-18 production in infected IECs especially when autophagy is inhibited. Finally, orally administered S. enterica serovar Worthington, which is recognized by human galectin-4 but not mouse galectin-4, translocated from the intestines to mesenteric lymph nodes less effectively in human galectin-4-transgenic mice than in littermate controls. Our results suggest that galectin-4 plays an important role in host-gut microbe interactions and prevents the dissemination of pathogens. The results of the study revealed a novel mechanism of host-microbe interactions that involves the direct binding of cytosolic lectins to glycans on intracellular microbes.


Asunto(s)
Galectina 4 , Inflamasomas , Animales , Ratones , Humanos , Inflamasomas/metabolismo , Galectina 4/metabolismo , Células Epiteliales/metabolismo , Bacterias , Antígenos O/metabolismo
14.
J Invest Dermatol ; 143(6): 913-924.e4, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36535362

RESUMEN

Sebaceous glands play an important role in maintaining the skin barrier function by producing lipids. Dysregulated lipid production in these glands may contribute to the pathogenesis of human skin diseases. Galectin-12, a member of the ß-galactoside‒binding lectin family, is preferentially expressed in adipocytes, where it regulates adipogenesis and functions as an intrinsic negative regulator of lipolysis. It is also expressed by sebocytes and contributes to the proliferation of this cell type. In this study, we show the association between galectin-12 expression and sebocyte differentiation. Galectin-12 knockdown in a human sebocyte cell line reduced lipogenesis and decreased the production of cholesteryl esters, triglycerides, free fatty acids, and cholesterol. Metabolomic analysis of skin surface lipids showed that the levels of the lipids mentioned earlier decreased in sebaceous gland‒specific galectin-12‒knockout mice compared with that in wild-type mice. In addition, galectin-12 positively regulated peroxisome proliferator‒activated receptor-γ transcriptional activity in sebocytes stimulated with fatty acids. Downregulating galectin-12 suppressed the expression of peroxisome proliferator‒activated receptor-γ target genes-acetyl-coenzyme A synthetase 2 gene ACS2 and diacylglycerol O-acyltransferase 1 gene DGAT1-that are required for fatty acid activation and cholesterol and triglyceride biosynthesis. In conclusion, galectin-12 is a positive regulator of sebaceous lipid metabolism with a potential role in the maintenance of skin homeostasis.


Asunto(s)
Metabolismo de los Lípidos , Glándulas Sebáceas , Humanos , Animales , Ratones , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Triglicéridos/metabolismo , Galectinas/genética , Galectinas/metabolismo
15.
JCI Insight ; 7(16)2022 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-35900871

RESUMEN

The epidermis is the outermost layer of skin. Here, we used targeted lipid profiling to characterize the biogeographic alterations of human epidermal lipids across 12 anatomically distinct body sites, and we used single-cell RNA-Seq to compare keratinocyte gene expression at acral and nonacral sites. We demonstrate that acral skin has low expression of EOS acyl-ceramides and the genes involved in their synthesis, as well as low expression of genes involved in filaggrin and keratin citrullination (PADI1 and PADI3) and corneodesmosome degradation, changes that are consistent with increased corneocyte retention. Several overarching principles governing epidermal lipid expression were also noted. For example, there was a strong negative correlation between the expression of 18-carbon and 22-carbon sphingoid base ceramides. Disease-specific alterations in epidermal lipid gene expression and their corresponding alterations to the epidermal lipidome were characterized. Lipid biomarkers with diagnostic utility for inflammatory and precancerous conditions were identified, and a 2-analyte diagnostic model of psoriasis was constructed using a step-forward algorithm. Finally, gene coexpression analysis revealed a strong connection between lipid and immune gene expression. This work highlights (a) mechanisms by which the epidermis is uniquely adapted for the specific environmental insults encountered at different body surfaces and (b) how inflammation-associated alterations in gene expression affect the epidermal lipidome.


Asunto(s)
Epidermis , Análisis de la Célula Individual , Carbono/metabolismo , Ceramidas/metabolismo , Epidermis/metabolismo , Humanos , Queratinocitos/metabolismo
16.
Glycobiology ; 32(9): 760-777, 2022 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-35789267

RESUMEN

Galectin-3 (GAL3) is a ß-galactoside-binding lectin expressed in CD4 T cells infected with human immunodeficiency virus-1 (HIV-1). GAL3 promotes HIV-1 budding by associating with ALIX and Gag p6. GAL3 has been shown to localize in membrane lipid rafts in dendritic cells and positively regulate cell migration. HIV-1 spreads between T cells by forming supramolecular structures (virological synapses [VSs]), whose integrity depends on lipid rafts. Here, we addressed the potential role of GAL3 in cell-to-cell transmission of HIV-1 in CD4 T cells. GAL3 expressed in donor cells was more important for facilitating HIV-1 cell-to-cell transfer than GAL3 expressed in target cells. GAL3 was found to be co-transferred with Gag from HIV-1-positive donor to HIV-1-negative target T cells. HIV-1 infection induced translocation of GAL3 together with Gag to the cell-cell interfaces and colocalize with GM1, where GAL3 facilitated VS formation. GAL3 regulated the coordinated transfer of Gag and flotillin-1 into plasma membrane fractions. Finally, depletion of GAL3 reduced the cholesterol levels in membrane lipid rafts in CD4 T cells. These findings provide evidence that endogenous GAL3 stimulates lipid raft components and facilitates intercellular HIV-1 transfer among CD4 T cells, offering another pathway by which GAL3 regulates HIV-1 infection. These findings may inform the treatment of HIV-1 infection based on targeting GAL3 to modulate lipid rafts.


Asunto(s)
Infecciones por VIH , VIH-1 , Proteínas Sanguíneas , Linfocitos T CD4-Positivos/metabolismo , Galectina 3/genética , Galectina 3/metabolismo , Galectinas , Humanos , Lípidos de la Membrana/análisis , Lípidos de la Membrana/metabolismo , Microdominios de Membrana/química
17.
Methods Mol Biol ; 2442: 353-365, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35320535

RESUMEN

Galectins are animal lectins that recognize ß-galactoside and bind glycans. Recent studies have indicated that cytosolic galectins recognize cytosolically exposed glycans and accumulate around endocytic vesicles or organelles damaged by various disruptive substances. Accumulated galectins engage other cytosolic proteins toward damaged vesicles, leading to cellular responses, such as autophagy. Disruptive substances include bacteria, viruses, particulate matters, and protein aggregates; thus, this process is implicated in the pathogenesis of various diseases. In this chapter, we describe methods for studying three disruptive substances: photosensitizers, Listeria monocytogenes, and Helicobacter pylori. We summarize the tools used for the detection of cytosolic galectin accumulation around damaged vesicles.


Asunto(s)
Autofagia , Citosol , Galectinas , Orgánulos , Vesículas Transportadoras , Animales , Citosol/química , Galectinas/análisis , Helicobacter pylori , Listeria monocytogenes , Lisosomas/química , Orgánulos/química , Fármacos Fotosensibilizantes/farmacología , Polisacáridos/metabolismo , Vesículas Transportadoras/química , Vesículas Transportadoras/efectos de los fármacos
18.
Angew Chem Int Ed Engl ; 61(14): e202116927, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35104385

RESUMEN

Multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters show great potentials for high color purity organic light-emitting diodes (OLEDs). However, the simultaneous realization of high photoluminescence quantum yield (PLQY) and high reverse intersystem crossing rate (kRISC ) is still a formidable challenge. Herein, a novel asymmetric MR-TADF emitter (2Cz-PTZ-BN) is designed that fully inherits the high PLQY and large kRISC values of the properly selected parent molecules. The resonating extended π-skeleton with peripheral protection can achieve a high PLQY of 96 % and a fast kRISC of above 1.0×105  s-1 , and boost the performance of corresponding pure green devices with an outstanding external quantum efficiency (EQE) of up to 32.8 % without utilizing any sensitizing hosts. Remarkably, the device sufficiently maintains a high EQE exceeding 23 % at a high luminance of 1000 cd m-2 , representing the highest value for reported green MR-TADF materials at the same luminescence.

19.
Small ; 18(4): e2106462, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34862733

RESUMEN

Multi-resonance thermally activated delayed fluorescence (MR-TADF) material, which possesses the ability to achieve narrowband emission in organic light-emitting diodes (OLEDs), is of significant importance for wide color gamut and high-resolution display applications. To date, MR-TADF material with narrow full width at half-maximum (FWHM) below 0.14 eV still remains a great challenge. Herein, through peripheral protection of MR framework by phenyl derivatives, four efficient narrowband MR-TADF emitters are successfully designed and synthesized. The introduction of peripheral phenyl-based moieties via a single bond significantly suppresses the high-frequency stretching vibrations and reduces the reorganization energies, accordingly deriving the resulting molecules with small FWMH values around 20 nm/0.11 eV and fast radiative decay rates exceeding 108 s-1 . The corresponding green OLED based on TPh-BN realizes excellent performance with the maximum external quantum efficiency (EQE) up to 28.9% without utilizing any sensitizing host and a relatively narrow FWHM of 0.14 eV (28 nm), which is smaller than the reported green MR-TADF molecules in current literatures. Especially, the devices show significantly reduced efficiency roll-off and relatively long operational lifetimes among the sensitizer-free MR-TADF devices. These results clearly indicate the promise of this design strategy for highly efficient OLEDs with ultra-high color purity.

20.
Glycobiology ; 32(1): 73-82, 2022 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-34791227

RESUMEN

Enhanced sebocyte proliferation is associated with the pathogenesis of human skin diseases related to sebaceous gland hyperfunction and androgens, which are known to induce sebocyte proliferation, are key mediators of this process. Galectin-12, a member of the ß-galactoside-binding lectin family that is preferentially expressed by adipocytes and functions as an intrinsic negative regulator of lipolysis, has been shown to be expressed by human sebocytes. In this study, we identified galectin-12 as an important intracellular regulator of sebocyte proliferation. Galectin-12 knockdown in the human SZ95 sebocyte line suppressed cell proliferation, and its overexpression promoted cell cycle progression. Inhibition of galectin-12 expression reduced the androgen-induced SZ95 sebocyte proliferation and growth of sebaceous glands in mice, respectively. The mRNA expression of the key cell cycle regulators cyclin A1 (CCNA1) and cyclin-dependent kinase 2CDK2 was reduced in galectin-12 knockdown SZ95 sebocytes, suggesting a pathway of galectin-12 regulation of sebocyte proliferation. Further, galectin-12 enhanced peroxisome proliferator-activated receptor gamma (PPARγ) expression and transcriptional activity in SZ95 sebocytes, consistent with our previous studies in adipocytes. Rosiglitazone, a PPARγ ligand, induced CCNA1 levels, suggesting that galectin-12 may upregulate CCNA1 expression via PPARγ. Our findings suggest the possibility of targeting galectin-12 to treat human sebaceous gland hyperfunction and androgen-associated skin diseases.


Asunto(s)
Ciclina A1 , Glándulas Sebáceas , Animales , Ciclo Celular/genética , Proliferación Celular , Ciclina A1/metabolismo , Quinasa 2 Dependiente de la Ciclina , Galectinas/genética , Galectinas/metabolismo , Ratones , Glándulas Sebáceas/metabolismo
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