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1.
bioRxiv ; 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38712161

RESUMEN

N,N-dimethyltryptamine (DMT) is a serotonergic psychedelic that is being investigated clinically for the treatment of psychiatric disorders. Although the neurophysiological effects of DMT in humans are well-characterized, similar studies in animal models as well as data on the neurochemical effects of DMT are generally lacking, which are critical for mechanistic understanding. In the current study, we combined behavioral analysis, high-density (32-channel) electroencephalography, and ultra-high-performance liquid chromatography-tandem mass spectrometry to simultaneously quantify changes in behavior, cortical neural dynamics, and levels of 17 neurochemicals in medial prefrontal and somatosensory cortices before, during, and after intravenous administration of three different doses of DMT (0.75 mg/kg, 3.75 mg/kg, 7.5 mg/kg) in male and female adult rats. All three doses of DMT produced head twitch response with most twitches observed after the low dose. DMT caused dose-dependent increases in serotonin and dopamine levels in both cortical sites along with a reduction in EEG spectral power in theta (4-10 Hz) and low gamma (25-55 Hz), and increase in power in delta (1-4 Hz), medium gamma (65-115), and high gamma (125-155 Hz) bands. Functional connectivity decreased in the delta band and increased across the gamma bands. In addition, we provide the first measurements of endogenous DMT in these cortical sites at levels comparable to serotonin and dopamine, which together with a previous study in occipital cortex, suggests a physiological role for endogenous DMT. This study represents one of the most comprehensive characterizations of psychedelic drug action in rats and the first to be conducted with DMT.

2.
Org Lett ; 26(17): 3646-3651, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38656111

RESUMEN

A new approach for the preparation of amides was developed using C-C bond cleavage that initiates C- to N-acyl transfer, employing activated ketones as acylation reagents and amine nucleophiles. The reaction was operational under the coupling reagent system that is commonly utilized for peptide bond formations. The method enables practical preparation of amides using linear and cyclic ketone substrates under mild conditions.

3.
Biochim Biophys Acta Gene Regul Mech ; 1867(2): 195030, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38670485

RESUMEN

Antiretroviral therapy-naive people living with HIV possess less fat than people without HIV. Previously, we found that HIV-1 transactivator of transcription (TAT) decreases fat in ob/ob mice. The TAT38 (a.a. 20-57) is important in the inhibition of adipogenesis and contains three functional domains: Cys-ZF domain (a.a. 20-35 TACTNCYCAKCCFQVC), core-domain (a.a. 36-46, FITKALGISYG), and protein transduction domain (PTD)(a.a. 47-57, RAKRRQRRR). Interestingly, the TAT38 region interacts with the Cyclin T1 of the P-TEFb complex, of which expression increases during adipogenesis. The X-ray crystallographic structure of the complex showed that the Cys-ZF and the core domain bind to the Cyclin T1 via hydrophobic interactions. To prepare TAT38 mimics with structural and functional similarities to TAT38, we replaced the core domain with a hydrophobic aliphatic amino acid (from carbon numbers 5 to 8). The TAT38 mimics with 6-hexanoic amino acid (TAT38 Ahx (C6)) and 7-heptanoic amino acid (TAT38 Ahp (C7)) inhibited adipogenesis of 3T3-L1 potently, reduced cellular triglyceride content, and decreased body weight of diet-induced obese (DIO) mice by 10.4-11 % in two weeks. The TAT38 and the TAT38 mimics potently repressed the adipogenic transcription factors genes, C/EBPα, PPARγ, and SREBP1. Also, they inhibit the phosphorylation of PPARγ. The TAT peptides may be promising candidates for development into a drug against obesity or diabetes.


Asunto(s)
Adipogénesis , PPAR gamma , Proteína 1 de Unión a los Elementos Reguladores de Esteroles , Productos del Gen tat del Virus de la Inmunodeficiencia Humana , Animales , PPAR gamma/metabolismo , Adipogénesis/efectos de los fármacos , Ratones , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/metabolismo , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/genética , Proteína alfa Potenciadora de Unión a CCAAT/metabolismo , Proteína alfa Potenciadora de Unión a CCAAT/genética , Células 3T3-L1 , Humanos , Regulación de la Expresión Génica , Ratones Obesos , Masculino , Ciclina T/metabolismo , Obesidad/metabolismo , Adipocitos/metabolismo , Ratones Endogámicos C57BL , Proteínas Potenciadoras de Unión a CCAAT
4.
Int J Biol Sci ; 20(5): 1688-1704, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38481807

RESUMEN

Background: Melanocortin 1 receptor (MC1R), a receptor of α-melanocyte-stimulating hormone (α-MSH), is exclusively present in melanocytes where α-MSH/MC1R stimulate melanin pigmentation through microphthalmia-associated transcription factor M (MITF-M). Toll-like receptor 4 (TLR4), a receptor of endotoxin lipopolysaccharide (LPS), is distributed in immune and other cell types including melanocytes where LPS/TLR4 activate transcriptional activity of nuclear factor (NF)-κB to express cytokines in innate immunity. LPS/TLR4 also up-regulate MITF-M-target melanogenic genes in melanocytes. Here, we propose a molecular target of antimelanogenic activity through elucidating inhibitory mechanism on α-MSH-induced melanogenic programs by benzimidazole-2-butanol (BI2B), an inhibitor of LPS/TLR4-activated transcriptional activity of NF-κB. Methods: Ultraviolet B (UV-B)-irradiated skins of HRM-2 hairless mice and α-MSH-activated melanocyte cultures were employed to examine melanogenic programs. Results: Topical treatment with BI2B ameliorated UV-B-irradiated skin hyperpigmentation in mice. BI2B suppressed the protein or mRNA levels of melanogenic markers, such as tyrosinase (TYR), MITF-M and proopiomelanocortin (POMC), in UV-B-exposed and pigmented skin tissues. Moreover, BI2B inhibited melanin pigmentation in UV-B-irradiated co-cultures of keratinocyte and melanocyte cells and that in α-MSH-activated melanocyte cultures. Mechanistically, BI2B inhibited the activation of cAMP response element-binding protein (CREB) in α-MSH-induced melanogenic programs and suppressed the expression of MITF-M at the promoter level. As a molecular target, BI2B primarily inhibited mitogen-activated protein kinase (MAPK) kinase 3 (MKK3)-catalyzed kinase activity on p38MAPK. Subsequently, BI2B interrupted downstream pathway of p38MAPK-mitogen and stress-activated protein kinase-1 (MSK1)-CREB-MITF-M, and suppressed MITF-M-target melanogenic genes, encoding enzymes TYR, TYR-related protein-1 (TRP-1) and dopachrome tautomerase (DCT) in melanin biosynthesis, and encoding proteins PMEL17 and Rab27A in the transfer of pigmented melanosomes to the overlaying keratinocytes in the skin. Conclusion: Targeting the MKK3-p38MAPK-MSK1-CREB-MITF-M pathway was suggested as a rationale to inhibit UV-B- or α-MSH-induced facultative melanogenesis and as a strategy to prevent acquired pigmentary disorders in the skin.


Asunto(s)
Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Hiperpigmentación , Animales , Ratones , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Melaninas/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , alfa-MSH/farmacología , alfa-MSH/metabolismo , Factor de Transcripción Asociado a Microftalmía/genética , Factor de Transcripción Asociado a Microftalmía/metabolismo , Lipopolisacáridos/toxicidad , Melanocitos/metabolismo , Hiperpigmentación/tratamiento farmacológico , Hiperpigmentación/metabolismo , Monofenol Monooxigenasa/metabolismo , Línea Celular Tumoral
5.
Phytomedicine ; 128: 155449, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38518644

RESUMEN

BACKGROUND: Peucedanum japonicum Thunb. (PJ) is a vegetable widely consumed in East Asia and is known to have anticancer and anti-inflammatory effects. However, the effect of PJ on muscle atrophy remains elusive. PURPOSE: This study aimed to investigate the effect of PJ and its active compound on dexamethasone (DEX)-induced muscle atrophy. METHODS: We performed qualitative and quantitative analysis of PJ using ultra-performance liquid chromatography-mass spectrometry tandem mass spectrometry (UPLC-MS/MS) and high-performance liquid chromatography (HPLC), respectively. The efficacy of PJ and its main compound 4-caffeoylquinic acid (CQA) on muscle atrophy was evaluated in DEX-induced myotube atrophy and DEX-induced muscle atrophy in mouse myoblasts (C2C12) and C57BL/6 mice, in vitro and in vivo, respectively. RESULTS: The UPLC-MS/MS and HPLC data showed that the concentration of 4-CQA in PJ was 18.845 mg/g. PJ and 4-CQA treatments significantly inhibited DEX-induced myotube atrophy by decreasing protein synthesis and glucocorticoid translocation to the nucleus in C2C12 myotubes. In addition, PJ enhanced myogenesis by upregulating myogenin and myogenic differentiation 1 in C2C12 cells. PJ supplementation effectively increased muscle function and mass, downregulated atrogenes, and decreased proteasome activity in C57BL/6 mice. Additionally, PJ effectively decreased the nuclear translocation of forkhead transcription factor 3 alpha by inhibiting glucocorticoid receptor. CONCLUSION: Overall, PJ and its active compound 4-CQA alleviated skeletal muscle atrophy by inhibiting protein degradation. Hence, our findings present PJ as a potential novel pharmaceutical candidate for the treatment of muscle atrophy.


Asunto(s)
Apiaceae , Dexametasona , Ratones Endogámicos C57BL , Atrofia Muscular , Extractos Vegetales , Ácido Quínico/análogos & derivados , Animales , Atrofia Muscular/inducido químicamente , Atrofia Muscular/tratamiento farmacológico , Dexametasona/farmacología , Ratones , Extractos Vegetales/farmacología , Extractos Vegetales/química , Apiaceae/química , Masculino , Línea Celular , Espectrometría de Masas en Tándem , Fibras Musculares Esqueléticas/efectos de los fármacos , Ácido Quínico/farmacología , Cromatografía Líquida de Alta Presión , Miogenina/metabolismo
6.
Nat Commun ; 15(1): 1004, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38307843

RESUMEN

Amyloid-ß (Aß) oligomers are implicated in the onset of Alzheimer's disease (AD). Herein, quinoline-derived half-curcumin-dioxaborine (Q-OB) fluorescent probe was designed for detecting Aß oligomers by finely tailoring the hydrophobicity of the biannulate donor motifs in donor-π-acceptor structure. Q-OB shows a great sensing potency in dynamically monitoring oligomerization of Aß during amyloid fibrillogenesis in vitro. In addition, we applied this strategy to fluorometrically analyze Aß self-assembly kinetics in the cerebrospinal fluids (CSF) of AD patients. The fluorescence intensity of Q-OB in AD patients' CSF revealed a marked change of log (I/I0) value of 0.34 ± 0.13 (cognitive normal), 0.15 ± 0.12 (mild cognitive impairment), and 0.14 ± 0.10 (AD dementia), guiding to distinguish a state of AD continuum for early diagnosis of AD. These studies demonstrate the potential of our approach can expand the currently available preclinical diagnostic platform for the early stages of AD, aiding in the disruption of pathological progression and the development of appropriate treatment strategies.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/líquido cefalorraquídeo , Péptidos beta-Amiloides/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Proteínas Amiloidogénicas , Proteínas tau/líquido cefalorraquídeo , Fragmentos de Péptidos/líquido cefalorraquídeo
7.
J Microbiol Biotechnol ; 34(4): 747-756, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38321650

RESUMEN

Chronic gut inflammation promotes the development of metabolic diseases such as obesity. There is growing evidence which suggests that dysbiosis in gut microbiota and metabolites disrupt the integrity of the intestinal barrier and significantly impact the level of inflammation in various tissues, including the liver and adipose tissues. Moreover, dietary sources are connected to the development of leaky gut syndrome through their interaction with the gut microbiota. This review examines the effects of these factors on intestinal microorganisms and the communication pathways between the gut-liver and gut-brain axis. The consumption of diets rich in fats and carbohydrates has been found to weaken the adherence of tight junction proteins in the gastrointestinal tract. Consequently, this allows endotoxins, such as lipopolysaccharides produced by detrimental bacteria, to permeate through portal veins, leading to metabolic endotoxemia and alterations in the gut microbiome composition with reduced production of metabolites, such as short-chain fatty acids. However, the precise correlation between gut microbiota and alternative sweeteners remains uncertain, necessitating further investigation. This study highlights the significance of exploring the impact of diet on gut microbiota and the underlying mechanisms in the gut-liver and gut-brain axis. Nevertheless, limited research on the gut-liver axis poses challenges in comprehending the intricate connections between diet and the gut-brain axis. This underscores the need for comprehensive studies to elucidate the intricate gut-brain mechanisms underlying intestinal health and microbiota.


Asunto(s)
Dieta , Disbiosis , Microbioma Gastrointestinal , Humanos , Bacterias/clasificación , Bacterias/metabolismo , Eje Cerebro-Intestino/fisiología , Dieta/efectos adversos , Disbiosis/microbiología , Microbioma Gastrointestinal/fisiología , Tracto Gastrointestinal/microbiología , Inflamación , Hígado/metabolismo
8.
Metabolites ; 14(1)2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38248865

RESUMEN

Black ginseng (BG) is processed ginseng traditionally made in Korea via the steaming and drying of ginseng root through three or more cycles, leading to changes in its appearance due to the Maillard reaction on its surface, resulting in a dark coloration. In this study, we explored markers for differentiating processed ginseng by analyzing the chemical characteristics of BG. We elucidated a new method for the structural identification of ginsenoside metabolites and described the features of processed ginseng using UPLC-QTOF-MS in the positive ion mode. We confirmed that maltose, glucose, and fructose, along with L-arginine, L-histidine, and L-lysine, were the key compounds responsible for the changes in the external quality of BG. These compounds can serve as important metabolic markers for distinguishing BG from conventionally processed ginseng. The major characteristics of white ginseng, red ginseng, and BG can be distinguished based on their high-polarity and low-polarity ginsenosides, and a precise method for the structural elucidation of ginsenosides in the positive ion mode is presented.

9.
J Proteome Res ; 23(1): 329-343, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38063806

RESUMEN

Psychiatric evaluation relies on subjective symptoms and behavioral observation, which sometimes leads to misdiagnosis. Despite previous efforts to utilize plasma proteins as objective markers, the depletion method is time-consuming. Therefore, this study aimed to enhance previous quantification methods and construct objective discriminative models for major psychiatric disorders using nondepleted plasma. Multiple reaction monitoring-mass spectrometry (MRM-MS) assays for quantifying 453 peptides in nondepleted plasma from 132 individuals [35 major depressive disorder (MDD), 47 bipolar disorder (BD), 23 schizophrenia (SCZ) patients, and 27 healthy controls (HC)] were developed. Pairwise discriminative models for MDD, BD, and SCZ, and a discriminative model between patients and HC were constructed by machine learning approaches. In addition, the proteins from nondepleted plasma-based discriminative models were compared with previously developed depleted plasma-based discriminative models. Discriminative models for MDD versus BD, BD versus SCZ, MDD versus SCZ, and patients versus HC were constructed with 11 to 13 proteins and showed reasonable performances (AUROC = 0.890-0.955). Most of the shared proteins between nondepleted and depleted plasma models had consistent directions of expression levels and were associated with neural signaling, inflammatory, and lipid metabolism pathways. These results suggest that multiprotein markers from nondepleted plasma have a potential role in psychiatric evaluation.


Asunto(s)
Trastorno Bipolar , Trastorno Depresivo Mayor , Esquizofrenia , Humanos , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/metabolismo , Trastorno Bipolar/diagnóstico , Trastorno Bipolar/metabolismo , Esquizofrenia/diagnóstico , Esquizofrenia/metabolismo , Espectrometría de Masas
10.
J Proteome Res ; 23(1): 249-263, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38064581

RESUMEN

In many cases of traumatic brain injury (TBI), conspicuous abnormalities, such as scalp wounds and intracranial hemorrhages, abate over time. However, many unnoticeable symptoms, including cognitive, emotional, and behavioral dysfunction, often last from several weeks to years after trauma, even for mild injuries. Moreover, the cause of such persistence of symptoms has not been examined extensively. Recent studies have implicated the dysregulation of the molecular system in the injured brain, necessitating an in-depth analysis of the proteome and signaling pathways that mediate the consequences of TBI. Thus, in this study, the brain proteomes of two TBI models were examined by quantitative proteomics during the recovery period to determine the molecular mechanisms of TBI. Our results show that the proteomes in both TBI models undergo distinct changes. A bioinformatics analysis demonstrated robust activation and inhibition of signaling pathways and core proteins that mediate biological processes after brain injury. These findings can help determine the molecular mechanisms that underlie the persistent effects of TBI and identify novel targets for drug interventions.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Lesiones Encefálicas , Animales , Roedores/metabolismo , Proteómica/métodos , Proteoma/genética , Proteoma/metabolismo , Lesiones Traumáticas del Encéfalo/metabolismo , Lesiones Encefálicas/metabolismo
11.
Sci Rep ; 13(1): 19786, 2023 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-37957236

RESUMEN

Some individuals with mild traumatic brain injury (mTBI), also known as concussion, have neuropsychiatric and physical problems that last longer than a few months. Symptoms following mTBI are not only impacted by the kind and severity of the injury but also by the post-injury experience and the individual's responses to it, making the persistence of mTBI particularly difficult to predict. We aimed to identify prognostic blood-based protein biomarkers predicting 6-month outcomes, in light of the clinical course after the injury, in a longitudinal mTBI cohort (N = 42). Among 420 target proteins quantified by multiple-reaction monitoring-mass spectrometry assays of blood samples, 31, 43, and 15 proteins were significantly associated with the poor recovery of neuropsychological symptoms at < 72 h, 1 week, and 1 month after the injury, respectively. Sequential associations among clinical assessments (depressive symptoms and cognitive function) affecting the 6-month outcomes were evaluated. Then, candidate biomarker proteins indirectly affecting the outcome via neuropsychological symptoms were identified. Using the identified proteins, prognostic models that can predict the 6-month outcome of mTBI were developed. These protein biomarkers established in the context of the clinical course of mTBI may have potential for clinical application.


Asunto(s)
Conmoción Encefálica , Humanos , Conmoción Encefálica/diagnóstico , Pronóstico , Proteómica , Biomarcadores , Progresión de la Enfermedad
12.
Antioxidants (Basel) ; 12(9)2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37760053

RESUMEN

Patulin (PAT) is a natural mycotoxin found in decaying pome fruits. Although some toxicological studies have been conducted on PAT, recent research has highlighted its anticancer and antifungal effects. However, studies have yet to examine the effects and molecular mechanisms of PAT in other metabolic diseases. Obesity is a chronic disease caused by excessive food intake and abnormal lifestyle, leading to low-grade inflammation. Therefore, this study aimed to elucidate the effect of PAT on obesity at the cellular level. PAT treatment reduced lipid accumulation, suppressed glucose and LDL uptake, inhibited lipid deposition and triglyceride synthesis, upregulated fatty acid oxidation-related genes (Pgc1α), and downregulated adipogenic/lipogenic genes (Pparγ and C/ebpα) in hypertrophied 3T3-L1 adipocytes. Additionally, PAT treatment enhanced mitochondrial respiration and mass in differentiated adipocytes and alleviated inflammatory response in activated RAW 264.7 macrophages. Moreover, PAT treatment downregulated pro-inflammatory genes (il-6, Tnf-α, Cox-2, and inos), suppressed lipopolysaccharide (LPS)-induced increase in inflammatory mediators (IL-6, TNF-α, and NO), and restored mitochondrial oxidative function in LPS-stimulated macrophages by improving oxygen consumption and mitochondrial integrity and suppressing ROS generation. Overall, these findings suggest a potential for PAT in the prevention of lipid accumulation and inflammation-related disorders.

13.
Materials (Basel) ; 16(18)2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37763442

RESUMEN

Decreasing hydride-induced embrittlement of zirconium-based cladding is a significant challenge for the successful dry storage of spent nuclear fuel. Herein, to radically minimize hydride-induced embrittlement, we used nanoparticles as sacrificial agents with a greater affinity than zirconium for hydrogen. Corrosion experiments in the presence of gold (Au) and palladium (Pd) nanoparticles under simulated pressurized water reactor (PWR) conditions revealed that the hydrogen content of the zirconium samples was remarkably reduced, with a maximum decrease efficiency of 53.9% using 65 nm Au and 53.8% using 50 nm Pd nanoparticles. This approach provides an effective strategy for preventing hydride-induced embrittlement of zirconium-based cladding.

14.
PLoS One ; 18(9): e0289625, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37733832

RESUMEN

Chloroplast genomes are valuable for inferring evolutionary relationships. We report the complete chloroplast genomes of 36 Corydalis spp. and one Fumaria species. We compared these genomes with 22 other taxa and investigated the genome structure, gene content, and evolutionary dynamics of the chloroplast genomes of 58 species, explored the structure, size, repeat sequences, and divergent hotspots of these genomes, conducted phylogenetic analysis, and identified nine types of chloroplast genome structures among Corydalis spp. The ndh gene family suffered inversion and rearrangement or was lost or pseudogenized throughout the chloroplast genomes of various Corydalis species. Analysis of five protein-coding genes revealed simple sequence repeats and repetitive sequences that can be potential molecular markers for species identification. Phylogenetic analysis revealed three subgenera in Corydalis. Subgenera Cremnocapnos and Sophorocapnos represented the Type 2 and 3 genome structures, respectively. Subgenus Corydalis included all types except type 3, suggesting that chloroplast genome structural diversity increased during its differentiation. Despite the explosive diversification of this subgenus, most endemic species collected from the Korean Peninsula shared only one type of genome structure, suggesting recent divergence. These findings will greatly improve our understanding of the chloroplast genome of Corydalis and may help develop effective molecular markers.


Asunto(s)
Fumaria , Genoma del Cloroplasto , Papaveraceae , Corydalis/genética , Genoma del Cloroplasto/genética , Papaveraceae/genética , Filogenia , Fumaria/genética , Evolución Biológica , Evolución Molecular
15.
Nanoscale ; 15(39): 15950-15955, 2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37698042

RESUMEN

We demonstrate the design strategy of free-standing Au nanocatalysts by correlating their physicochemical characteristics with photocatalytic performance. By tailoring the particle size and surface characteristics, we found that small Au nanocatalysts called Au nanoclusters with discrete energy levels are more effective than large metallic Au nanoparticles, while the microenvironments (e.g., charge status and hydrophilicity/hydrophobicity) around the surface of Au-nanoclusters are crucial in determining the performance. With the optimized Au nanocatalyst, under visible light, decarboxylative radical addition reactions for C-C bond formation (i.e., Giese reaction) were first achieved with high yields and further utilized for the preparation of one of the bioactive γ-aminobutyric acid derivatives, pregabalin (Lyrica®), demonstrating its potential in pharmaceutical applications.

16.
Sci Rep ; 13(1): 13074, 2023 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-37567910

RESUMEN

Nephritis is common in systemic lupus erythematosus patients and is associated with hyper-activation of immune and renal cells. Although mesenchymal stem cells (MSCs) ameliorate nephritis by inhibiting T and B cells, whether MSCs directly affect renal cells is unclear. To address this issue, we examined the direct effect of MSCs on renal cells with a focus on chemokines. We found that expression of CCL2, CCL3, CCL4, CCL5, CCL8, CCL19, and CXCL10 increased 1.6-5.6-fold in the kidney of lupus-prone MRL.Faslpr mice with advancing age from 9 to 16 weeks. Although MSCs inhibited the increase in the expression of most chemokines by 52-95%, they further increased CCL8 expression by 290%. Using renal cells, we next investigated how MSCs enhanced CCL8 expression. CCL8 was expressed by podocytes, but not by tubular cells. MSCs enhanced CCL8 expression by podocytes in a contact-dependent manner, which was proved by transwell assay and blocking with anti-VCAM-1 antibody. Finally, we showed that CCL8 itself activated MSCs to produce more immunosuppressive factors (IL-10, IDO, TGF-ß1, and iNOS) and to inhibit more strongly IFN-γ production by T cells. Taken together, our data demonstrate that MSCs activate podocytes to produce CCL8 in a contact-dependent manner and conversely, podocyte-derived CCL8 might potentiate immunosuppressive activity of MSCs in a paracrine fashion. Our study documents a previously unrecognized therapeutic mechanism of MSCs in nephritis.


Asunto(s)
Lupus Eritematoso Sistémico , Nefritis Lúpica , Células Madre Mesenquimatosas , Podocitos , Animales , Ratones , Quimiocinas/metabolismo , Ratones Endogámicos MRL lpr , Podocitos/metabolismo
17.
ACS Chem Neurosci ; 14(17): 3025-3034, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37552840

RESUMEN

Abnormal assembly of amyloid ß (Aß) in the brain is implicated in Alzheimer's disease (AD) and is associated with cognitive impairments. Since Aß accumulation occurs in advance of the onset of clinical symptoms, identifying preventable drug candidates regulating Aß accumulation is regarded as a promising approach in AD therapeutic. Herein, we synthesized eight Yonsei Institute of pharmaceutical sciences Alzheimer's Drug (YIAD) compounds based on 5-benzyl-6-phenylbenzo[4,5]imidazo[1,2-a]pyrrolo[2,1-c]pyrazine structures. Subsequently, YIAD-0203 and YIAD-0205 were selected as effective candidates via thioflavin T assays and gel electrophoresis. The potential therapeutic effect of YIAD-0203 and YIAD-0205 on Aß aggregates was investigated through an AD transgenic mouse model with five familial AD mutations (5XFAD) by oral gavage. Significant amounts of Aß plaque and oligomer reduction were observed in the hippocampus region of both 4.3-month-old (early stage of AD) and 6.0-month-old (mid stage of AD) YIAD-0205-treated 5XFAD mice brains when compared to the nontreated brains. The ability of YIAD-0205 to ameliorate Aß aggregates in the early and mid stages of AD progression supports the notion that YIAD-0205 could be utilized as a reliable scaffold for the development of preventive AD drug candidates.


Asunto(s)
Enfermedad de Alzheimer , Ratones , Animales , Ratones Transgénicos , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Amiloide , Imidazoles , Modelos Animales de Enfermedad , Placa Amiloide , Precursor de Proteína beta-Amiloide/metabolismo
18.
Seizure ; 111: 87-97, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37556985

RESUMEN

PURPOSE: Numerous inventories to identify felt stigma (FS) in people living with epilepsy (PLWE) have been developed. Past studies have mainly focused on the relationship between FS scores and clinical factors, making it challenging to delineate FS proportions and compare FS between groups. We aimed to integrate FS proportions in PLWE and compare them by continent. METHODS: We searched MEDLINE, EMBASE, the Cochrane Library, Web of Science, and Scopus. Among the identified studies, we chose the ones providing an FS proportion measured by Jacoby's Stigma Scale (JSS) and its revised version (JSS-R) in PLWE. We applied the random-effects model. RESULTS: A total of 63 datasets from 47 studies were included. There were 29,924 PLWE, with 14,323 of them experiencing FS. The overall FS proportion was 48.4%. Of these datasets, 51 used JSS, and 12 used JSS-R. The FS proportions were 44.9% for the former and 62.1% for the latter, with significant heterogeneity. In the intercontinental comparison with 51 datasets employing JSS, the difference in FS proportions was insignificant: 51.2% in Africa, 47.2% in Europe, 35.4% in Asia, and 28.8% in the Middle East. Furthermore, the meta-regression revealed that the year of each primary study did not influence the FS proportion. CONCLUSION: Among PLWE, FS proportions depended on the choice of a measurement tool. When measured using JSS, the FS proportion was 44.9%, while it was 62.1% when evaluated with JSS-R. Even though the FS proportions were integrated differently, no substantial differences were observed between continents.

19.
Sci Rep ; 13(1): 10889, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37407605

RESUMEN

Alzheimer's disease (AD) is characterized by misfolding, oligomerization, and accumulation of amyloid-ß (Aß) peptides in the brain. Aß monomers transform into Aß oligomers, which are toxic species, inducing tau hyperphosphorylation and the downstream effects on microglia and astrocytes, triggering synaptic and cognitive dysfunctions. The oligomers then deposit into Aß plaques, primarily composed of ß-stranded fibrils, required for definitive AD diagnosis. As amyloid burden plays the pivotal role in AD pathogenesis, many efforts are devoted in preventing amyloidosis as a therapeutic approach to impede the disease progression. Here, we discovered carprofen, a non-steroidal anti-inflammatory drug, accelerates Aß aggregating into fibrils and increases Aß plaques when intraperitoneally injected to 5XFAD transgenic mouse model. However, the drug seems to alleviate the key Alzheimer-like phenotypes induced by Aß aggregation as we found attenuated neuroinflammation, improved post-synaptic density expression, associated with synaptic plasticity, and decreased phosphorylated tau levels. Carprofen also rescued impaired working memory as we discovered improved spontaneous alternation performance through Y-maze test assessed with Aß(1-42)-infused mouse model. Collectively, while carprofen accelerates the conversion of Aß monomers into fibrils in vitro, the drug ameliorates the major pathological hallmarks of AD in vivo.


Asunto(s)
Enfermedad de Alzheimer , Ratones , Animales , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Ratones Transgénicos , Péptidos beta-Amiloides/metabolismo , Carbazoles/farmacología , Carbazoles/uso terapéutico , Trastornos de la Memoria/patología , Modelos Animales de Enfermedad
20.
Micromachines (Basel) ; 14(4)2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-37420948

RESUMEN

Beam steering technology is crucial for radio frequency and infrared telecommunication signal processing. Microelectromechanical systems (MEMS) are typically used for beam steering in infrared optics-based fields but have slow operational speeds. An alternative solution is to use tunable metasurfaces. Since graphene has gate-tunable optical properties, it is widely used in electrically tunable optical devices due to ultrathin physical thickness. We propose a tunable metasurface structure using graphene in a metal gap structure that can exhibit a fast-operating speed through bias control. The proposed structure can change beam steering and can focus immediately by controlling the Fermi energy distribution on the metasurface, thus overcoming the limitations of MEMS. The operation is numerically demonstrated through finite element method simulations.

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