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1.
Small ; 19(50): e2304610, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37632302

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune disease commonly associated with the accumulation of hyperactive immune cells (HICs), particularly macrophages of pro-inflammatory (M1) phenotype, accompanied by the elevated level of reactive oxygen species (ROS), decreased pH and O2 content in joint synovium. In this work, an immunomodulatory nanosystem (IMN) is developed for RA therapy by modulating and restoring the function of HICs in inflamed tissues. Manganese tetraoxide nanoparticles (Mn3 O4 ) nanoparticles anchored on UiO-66-NH2 are designed, and then the hybrid is coated with Mn-EGCG film, further wrapped with HA to obtain the final nanocomposite of UiO-66-NH2 @Mn3 O4 /Mn-EGCG@HA (termed as UMnEH). When UMnEH diffuses to the inflammatory site of RA synovium, the stimulation of microwave (MW) irradiation and low pH trigger the slow dissociation of Mn-EGCG film. Then the endogenously overexpressed hydrogen peroxide (H2 O2 ) disintegrates the exposed Mn3 O4 NPs to promote ROS scavenging and O2 generation. Assisted by MW irradiation, the elevated O2 content in the RA microenvironment down-regulates the expression of hypoxia-inducible factor-1α (HIF-1α). Coupled with the clearance of ROS, it promotes the re-polarization of M1 phenotype macrophages into anti-inflammatory (M2) phenotype macrophages. Therefore, the multifunctional UMnEH nanoplatform, as the IMN, exhibits a promising potential to modulate and restore the function of HICs and has an exciting prospect in the treatment of RA.


Assuntos
Artrite Reumatoide , Nanocompostos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Manganês , Catalase , Micro-Ondas , Artrite Reumatoide/tratamento farmacológico , Oxigênio/metabolismo
2.
RSC Adv ; 12(37): 24242-24251, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36128527

RESUMO

In order to investigate the solubility behavior of lignin in formic acid (FA) solution Phragmites australis biomass was subjected to a sequential two-step formosolv fractionation using 88% FA followed by 70% FA to obtain four specific lignin fractions, designated as IFL-88%, IFSL-70%, IFIL-70% and IFL-EtAc. The structures of the four isolated lignin fractions were successfully characterized by gel permeation chromatography (GPC), Fourier transform infrared (FTIR) spectroscopy, two-dimensional heteronuclear single quantum coherence nuclear magnetic resonance spectroscopy (2D-HSQC NMR), thermogravimetric analysis (TGA), and gas chromatography-mass spectroscopy (GC/MS). Furthermore, the total phenolic content of the four isolated lignin samples was assessed by Folin-Ciocalteu analysis. The data from structural properties revealed that depolymerization of the isolated lignin fractions occurred via ß-O-4 cleavage, accompanied by competitive condensation reaction. Interestingly, 70% aqueous FA could separate specific lignin fractions with different antioxidant capacities of ABTS˙+ and DPPH radical scavenging activity. Due to the high total phenolic hydroxyl content (25%) and low molecular weight (Mw = 2760 Da) and polydispersity index (PDI = 1.5), IFL-EtAc lignin showed excellent antioxidant activity at the same concentration of 2.0 mg mL-1 in comparison with three other isolated lignin fractions, and it was even equal to that of commercial antioxidant butylated hydroxytoluene (BHT). These findings are helpful to separate specific lignins with higher value as potential antioxidants by sequential two-step formosolv fractionation in lignin chemistry.

3.
Molecules ; 27(9)2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35566256

RESUMO

The formosolv fractionation process has been demonstrated to be an effective approach toward lignin recovery as an antioxidant from lignocellulosic biomass. In this study, four lignin fractions, FL-88%, FSL-70%, FIL-70% and FL-EtAc, were isolated from Phragmites australis biomass through two-step formosolv fractionation (88% formic acid delignification followed by 70% aqueous formic acid fractionation). To better understand the structural properties of the lignin obtained from this fractionation process, four isolated lignins were successfully characterized by gel permeation chromatography (GPC), Fourier transform infrared (FT-IR), two-dimensional heteronuclear single quantum coherence nuclear magnetic resonance (2D-HSQC NMR) spectroscopy, thermogravimetric analysis (TGA) and gas chromatograph-mass spectroscopy (GC/MS). It was found that lignin depolymerization via ß-O-4 cleavage occurred via a formylation, elimination and hydrolysis mechanism, accompanied by a competitive condensation reaction. Noteworthily, two-step formosolv fractionation can produce specific lignin fractions with different ABTS and DPPH radical scavenging activities. The FL-EtAc fraction with low molecular weight (Mw = 2748 Da) and good homogeneity (PDI = 1.5) showed excellent antioxidant activity, compared with the other three isolated lignin fractions, even equal to that of commercial antioxidant BHT at the same concentration of 2.0 mg·mL-1. These findings are of great help for specific lignin from biomass as a natural antioxidant in the future.


Assuntos
Antioxidantes , Lignina , Antioxidantes/química , Fracionamento Químico/métodos , Hidrólise , Lignina/química , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Exp Ther Med ; 14(4): 2943-2946, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29042907

RESUMO

This study evaluated the use of conventional therapy combined with puerarin on ischemic stroke. Eighty patients with ischemic stroke admitted to Tangshan Gongren Hospital from March 2014 to September 2015 were randomly divided into two groups. The control group was treated with conventional therapy. The observation group was treated with an additional puerarin injection of 400 mg/day. The patients in both groups were examined for clinical neurological signs and symptoms. The levels of biochemical markers as well as changes in hemorheology were measured after the intervention and compared among the groups. Our results indicate that the language expression was significantly better in the observation group after the intervention (p<0.05). Additionally, the aphasia quotient was higher (p<0.05), the neurological deficit score was lower (p<0.05), and the functional ability score was higher (p<0.05). The plasma S-100B and NSE levels were lower (p<0.05), the whole blood viscosity and plasma viscosity were lower (p<0.05), and the levels of corticotropin-releasing hormone, corticotropin, cortisol, adrenaline and norepinephrine were lower (p<0.05). Our findings led to the conclusion that the use of puerarin can effectively improve the language function, reduce neurological damage, reduce blood viscosity, reduce stress response and improve quality of life.

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