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1.
Food Chem Toxicol ; 188: 114652, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38583502

RESUMEN

The estrogen-like effect of bisphenol A (BPA) disrupting the maintenance of functional male germ cells is associated with male sub-fertility. This study investigated toxicity of male germ cells induced by four bisphenol analogs: BPA, BPAF, BPF, and BPS. The investigation of bisphenol analogs' impact on male germ cells included assessing proliferation, apoptosis induction, and the capacity to generate reactive oxygen species (ROS) in GC-1 spermatogonia (spg) cells, specifically type B spermatogonia. Additionally, the therapeutic potential and protective effects of N-Acetyl Cysteine (NAC) and NF-κB inhibitor parthenolide was evaluated. In comparison to BPA, BPF and BPS, BPAF exhibited the most pronounced adverse effect in GC-1 spg cell proliferation. This effect was characterized by pronounced inhibition of phosphorylation of PI3K, AKT, and mTOR, along with increased release of cytochrome c and subsequent cleavages of caspase 3, caspase 7, and poly (ADP-ribose) polymerase. Both NAC and parthenolide were effective reducing cellular ROS induced by BPAF. However, only NAC demonstrated a substantial recovery in proliferation, accompanied by a significant reduction in cytochrome c release and cleaved PARP. These results suggest that NAC supplementation may play an effective therapeutic role in countering germ cell toxicity induced by environmental pollutants with robust oxidative stress-generating capacity.


Asunto(s)
Acetilcisteína , Apoptosis , Compuestos de Bencidrilo , Proliferación Celular , Fenoles , Especies Reactivas de Oxígeno , Especies Reactivas de Oxígeno/metabolismo , Masculino , Fenoles/toxicidad , Animales , Compuestos de Bencidrilo/toxicidad , Acetilcisteína/farmacología , Ratones , Proliferación Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Sesquiterpenos/farmacología , Línea Celular , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Espermatogonias/efectos de los fármacos , Espermatogonias/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , FN-kappa B/metabolismo
2.
J Nanosci Nanotechnol ; 21(8): 4303-4309, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-33714318

RESUMEN

Synaptic devices, which are considered as one of the most important components of neuromorphic system, require a memory effect to store weight values, a high integrity for compact system, and a wide window to guarantee an accurate programming between each weight level. In this regard, memristive devices such as resistive random access memory (RRAM) and phase change memory (PCM) have been intensely studied; however, these devices have quite high current-level despite their state, which would be an issue if a deep and massive neural network is implemented with these devices since a large amount of current-sum needs to flow through a single electrode line. Organic transistor is one of the potential candidates as synaptic device owing to flexibility and a low current drivability for low power consumption during inference. In this paper, we investigate the performance and power consumption of neuromorphic system composed of organic synaptic transistors conducting a pattern recognition simulation with MNIST handwritten digit data set. It is analyzed according to threshold voltage (VT) window, device variation, and the number of available states. The classification accuracy is not affected by VT window if the device variation is not considered, but the current sum ratio between answer node and the rest 9 nodes varies. In contrast, the accuracy is significantly degraded as increasing the device variation; however, the classification rate is less affected when the number of device states is fewer.


Asunto(s)
Redes Neurales de la Computación , Simulación por Computador
3.
BMC Complement Med Ther ; 20(1): 144, 2020 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-32398000

RESUMEN

BACKGROUND: Dermal papilla cells (DPCs) play a key role in hair growth among the various cell types in hair follicles. Especially, DPCs determine the fate of hair follicle such as anagen to telogen transition and play a pivotal role in androgenic alopecia (AGA). This study was performed to elucidate the hair growth promoting effects of Polygonum multiflorum extract (PM extract) in cultured human DPCs and its underlying mechanisms. METHODS: The effects of PM extract on cultured DPCs were investigated. Cell viability and mitochondrial activity were measured by CCK-8 and JC-1 analysis, respectively. Western blotting, dot blotting, ELISA analysis, immunocytochemistry and real-time PCR analysis were also performed to elucidate the changes in protein and mRNA levels induced by PM extract. 3D cultured DPC spheroids were constructed for mimicking the in vivo DPs. The hair growth stimulatory effect of PM extract was evaluated using human hair follicle organ culture model. RESULTS: PM extract increased the viability and mitochondrial activity in cultured human DPCs in a dose dependent manner. The expression of Bcl2, an anti-apoptotic protein expressed dominantly in anagen was significantly increased and that of BAD, a pro-apoptotic protein expressed in early catagen was decreased by PM extract in cultured DPCs and/or 3D DPC spheroid culture. PM extract also decreased the expression of catagen inducing protein, Dkk-1. Growth factors including IGFBP2, PDGF and VEGF were increased by PM extract, revealed by dot blot protein analysis. We also have found that PM extract could reverse the androgenic effects of dihydrotestosterone (DHT), the most potent androgen. Finally, PM extract prolonged the anagen of human hair follicles by inhibiting catagen entry in human hair follicle organ culture model. CONCLUSION: Our data strongly suggest that PM extract could promote hair growth by elongating the anagen and/or delaying the catagen induction of hair follicles through activation of DPCs.


Asunto(s)
Andrógenos/metabolismo , Fallopia multiflora , Folículo Piloso/efectos de los fármacos , Extractos Vegetales/farmacología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Cabello/crecimiento & desarrollo , Humanos , Técnicas de Cultivo de Órganos , República de Corea
4.
Sci Rep ; 9(1): 13507, 2019 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-31534155

RESUMEN

Carnitine (CAR), an amino acid derivative, has great potential as a facial exfoliating agent owing to its calcium chelating property under weakly acidic or neutral conditions. However, its application is limited by its poor transdermal penetration. To optimise its exfoliation efficacy with minimal concentration, we propose the ion-pair method. The ionic interaction between CAR and a zwitterionic substance was successfully monitored by measuring conductivity. The alterations of penetration and exfoliation efficacy for CAR addition to different types of counter ions were investigated in vitro and in vivo. We found that hydrogenated soya phosphatidylcholine (HSC), an amphiphilic counter ion, significantly increases the stratum corneum penetration and exfoliation efficacy of CAR. The changes of the CAR-HSC ionic interaction in the presence of calcium ions were also investigated by 1H nuclear magnetic resonance (NMR) spectroscopy. The NMR spectra for amino groups of CAR first decreased with HSC and then gradually recovered and shifted as calcium ions were added. From the results, a noble exfoliating complex of CAR with high exfoliation efficacy could be proposed. Moreover, the results demonstrate that NMR spectroscopy is useful to obtain direct experimental evidence of the molecular dynamics simulations of the alteration of an exfoliating complex as it penetrates.


Asunto(s)
Administración Cutánea , Carnitina/farmacología , Sistemas de Liberación de Medicamentos/métodos , Sistemas de Transporte de Aminoácidos Neutros/química , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Aminoácidos , Antiinflamatorios no Esteroideos/química , Carnitina/metabolismo , Iones , Espectroscopía de Resonancia Magnética , Piel/metabolismo , Absorción Cutánea/fisiología
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