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1.
Environ Sci Technol ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39140966

RESUMO

Diisobutyl phthalate (DiBP) is commonly used in the plastics industry, and recent studies have shown that environmental exposure and accumulation in the food chain caused inflammation in some organs. However, the underlying mechanisms by which DiBP affects oocyte quality have not yet been fully defined. We used immunostaining and fluorescence to evaluate the effects of DiBP exposure and demonstrated that it impaired the morphology of matured porcine oocytes through generation of cytoplasmic fragmentation, accompanied by the perturbed dynamics of the spindle and actin cytoskeleton, misdistributed endoplasmic reticulum, as well as partial exocytosis of cortical granules and ovastacin. Moreover, analysis of Smart RNA-seq found that DiBP-induced aberrant oocyte maturation could be induced by abnormal mitochondrial function and apoptosis. Importantly, we discovered that supplementation with pyrroloquinoline quinone (PQQ) significantly attenuated the meiotic abnormalities induced by DiBP exposure through the modulation of reactive oxygen species levels. Our findings demonstrated that DiBP exposure adversely affects oocyte meiotic maturation and that PQQ supplementation was an effective strategy to protect oocyte quality against DiBP exposure.

2.
Insect Sci ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39126186

RESUMO

Circadian rhythms are self-sustained endogenous oscillations that are found in all living organisms. In insects, circadian rhythms control a wide variety of behavioral and physiological processes, including feeding, locomotion, mating, and metabolism. While the role of circadian rhythms in adult insects is well-understood, it is largely unexplored in larvae. This study investigates the potential for larval synchronized activity in the red flour beetle (Tribolium castaneum), a species exhibiting solitary and aggregation phases. We hypothesized that, similar to adults, larvae would exhibit a daily activity pattern governed by an endogenous circadian clock. We further predicted that the transition between the solitary and gregarious phases extends to unique temporal activity patterns. Our results revealed unique timekeeper gene expression in larvae, leading to a distinct daily rhythm characterized by nocturnal activity. Cues indicating on potential cannibalism did not change daily activity peak. However, the absence of these cues significantly reduced the proportion of rhythmic larvae and led to higher variation in peak activity, highlighting the crucial role of social interactions in shaping their rhythmicity. This study sheds light on the evolution and function of larval synchronization in group-living insects, offering novel insights into this complex behavior.

3.
In Silico Pharmacol ; 12(2): 73, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39144917

RESUMO

Bisphenol A (BPA), an endocrine-disrupting chemical, poses significant health problems due to its induction of oxidative stress, inflammation, etc. Whereas Ficus exasperata Vahl leaf (FEVL) was reported for its ethnopharmacological properties against several ailments owing to its antioxidant, anti-inflammatory properties, etc. Here, we aim to elucidate and identify the bioactive compounds of aqueous extract of FEVL (AEFEVL) against BPA-induced toxicity using in vivo and in silico assessments. To determine the BPA toxicity mechanism and safe doses of AEFEVL, graded doses of BPA (0-400 µM) and AEFEVL (0-2.0 mg/10 g diets) were separately fed to flies to evaluate survival rates and specific biochemical markers. The mitigating effect of AEFEVL (0.5 and 1.0 mg/10 g diet) against BPA (100 and 200 µM)-induced toxicity in the flies after 7-day exposure was also carried out. Additionally, molecular docking analysis of BPA and BPA-o-quinone (BPAQ) against selected antioxidant targets, and HPLC-MS-revealed AEFEVL compounds against Keap-1 and IKKß targets, followed by ADMET analysis, was conducted. Emergence rate, climbing ability, acetylcholinesterase, monoamine oxidase-B, and glutathione-S-transferase activities, and levels of total thiols, non-protein thiols, nitric oxide, protein carbonyl, malondialdehyde, and cell viability were evaluated. BPA-induced altered biochemical and behavioral parameters were significantly mitigated by AEFEVL in the flies (p < 0.05). BPAQ followed by BPA exhibited higher inhibitory activity, and epigallocatechin (EGC) showed the highest inhibitory activity among the AEFEVL compounds with desirable ADMET properties. Conclusively, our findings revealed that EGC might be responsible for the mitigative effect displayed by AEFEVL in BPA-induced toxicity in D. melanogaster.

4.
Eur J Med Chem ; 277: 116763, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39146834

RESUMO

5-Methoxy-3-(5-methoxyindolin-2-yl)-1H-indole (3), whose structure was unambiguously elucidated by X-ray analysis, was identified as a multi-target compound with potential application in neurodegenerative diseases. It is a low nanomolar inhibitor of QR2 (IC50 = 7.7 nM), with greater potency than melatonin and comparable efficacy to the most potent QR2 inhibitors described to date. Molecular docking studies revealed the potential binding mode of 3 to QR2, which explains its superior potency compared to melatonin. Furthermore, compound 3 inhibits hMAO-A, hMAO-B and hLOX-5 in the low micromolar range and is an excellent ROS scavenger. In phenotypic assays, compound 3 showed neuroprotective activity in a cellular model of oxidative stress damage, it was non-toxic, and was able to activate neurogenesis from neural stem-cell niches of adult mice. These excellent biological properties, together with its both good in silico and in vitro drug-like profile, highlight compound 3 as a promising drug candidate for neurodegenerative diseases.

5.
Proc Natl Acad Sci U S A ; 121(33): e2405836121, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39116128

RESUMO

The 2011 discovery of the first rare earth-dependent enzyme in methylotrophic Methylobacterium extorquens AM1 prompted intensive research toward understanding the unique chemistry at play in these systems. This enzyme, an alcohol dehydrogenase (ADH), features a La3+ ion closely associated with redox-active coenzyme pyrroloquinoline quinone (PQQ) and is structurally homologous to the Ca2+-dependent ADH from the same organism. AM1 also produces a periplasmic PQQ-binding protein, PqqT, which we have now structurally characterized to 1.46-Å resolution by X-ray diffraction. This crystal structure reveals a Lys residue hydrogen-bonded to PQQ at the site analogously occupied by a Lewis acidic cation in ADH. Accordingly, we prepared K142A- and K142D-PqqT variants to assess the relevance of this site toward metal binding. Isothermal titration calorimetry experiments and titrations monitored by UV-Vis absorption and emission spectroscopies support that K142D-PqqT binds tightly (Kd = 0.6 ± 0.2 µM) to La3+ in the presence of bound PQQ and produces spectral signatures consistent with those of ADH enzymes. These spectral signatures are not observed for WT- or K142A-variants or upon addition of Ca2+ to PQQ ⸦ K142D-PqqT. Addition of benzyl alcohol to La3+-bound PQQ ⸦ K142D-PqqT (but not Ca2+-bound PQQ ⸦ K142D-PqqT, or La3+-bound PQQ ⸦ WT-PqqT) produces spectroscopic changes associated with PQQ reduction, and chemical trapping experiments reveal the production of benzaldehyde, supporting ADH activity. By creating a metal binding site that mimics native ADH enzymes, we present a rare earth-dependent artificial metalloenzyme primed for future mechanistic, biocatalytic, and biosensing applications.


Assuntos
Methylobacterium extorquens , Methylobacterium extorquens/enzimologia , Methylobacterium extorquens/metabolismo , Metaloproteínas/química , Metaloproteínas/metabolismo , Álcool Desidrogenase/metabolismo , Álcool Desidrogenase/química , Cristalografia por Raios X , Cofator PQQ/metabolismo , Cofator PQQ/química , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Metais Terras Raras/química , Metais Terras Raras/metabolismo , Modelos Moleculares , Lantânio/química , Lantânio/metabolismo
6.
Molecules ; 29(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38999117

RESUMO

Oleum cinnamomi (OCM) is a volatile component of the Cinnamomum cassia Presl in the Lauraceae family, which displays broad-spectrum antibacterial properties. It has been found that OCM has a significant inhibitory effect against Cutibacterium acnes (C. acnes), but the precise target and molecular mechanism are still not fully understood. In this study, the antibacterial activity of OCM against C. acnes and its potential effect on cell membranes were elucidated. Metabolomics methods were used to reveal metabolic pathways, and proteomics was used to explore the targets of OCM inhibiting C. acnes. The yield of the OCM was 3.3% (w/w). A total of 19 compounds were identified, representing 96.213% of the total OCM composition, with the major constituents being phenylpropanoids (36.84%), sesquiterpenoids (26.32%), and monoterpenoids (15.79%). The main component identified was trans-cinnamaldehyde (85.308%). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of OCM on C. acnes were 60 µg/mL and 180 µg/mL, respectively. The modified proteomics results indicate that cinnamaldehyde was the main bioactive ingredient within OCM, which covalently modifies the ABC transporter adenosine triphosphate (ATP)-binding protein and nicotinamide adenine dinucleotide (NADH)-quinone oxidoreductase, hindering the amino acid transport process, and disrupting the balance between NADH and nicotinamide adenine dinucleoside phosphorus (NAD+), thereby hindering energy metabolism. We have reported for the first time that OCM exerts an antibacterial effect by covalent binding of cinnamaldehyde to target proteins, providing potential and interesting targets to explore new control strategies for gram-positive anaerobic bacteria.


Assuntos
Antibacterianos , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Propionibacteriaceae/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Proteômica/métodos , Acroleína/análogos & derivados , Acroleína/farmacologia , Acroleína/química , Metabolômica/métodos
7.
Talanta ; 279: 126611, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39067202

RESUMO

Peptidyl arginine deiminase 4 (PAD4) plays a critical role in many autoimmune diseases including rheumatoid arthritis. Herein, a trypsin assisted highly immunoassay method was established to determine PAD4 activity and screen potent inhibitors from herbal plants extracts and purified natural products. The method was applied to determine endogenous PAD4 activity in both cell and tissue lysates, as well as the inhibitory effects of 20 herbal plants and 50 purified natural products. The Cinnamomi ramulus extract showed strongest inhibitory potency with IC50 value lower than 5 µg/mL. Meanwhile, pyrroloquinoline quinone (PQQ), widely used as a dietary supplement, was discovered as a promising PAD4 inhibitor with an IC50 value lower than 4 µM. The inhibition kinetic analysis, drug affinity response target stability (DARTS) and molecular docking were performed to confirm the interaction between PQQ and PAD4. This method has great potential for researchers to monitor activities and discover potential inhibitors of PAD4.

8.
J Hazard Mater ; 476: 135122, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38986411

RESUMO

The extensive utilization of rubber-related products can lead to a substantial release of p-phenylenediamine (PPD) antioxidants into the environment. In recent years, studies mainly focus on the pollution characteristics and health risks of PM2.5-bound PPDs. This study presents long-time scale data of PPDs and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone (6PPD-Q) in PM2.5 and proposes the innovative use of PPDs as new markers for vehicular emissions in the Positive Matrix Factorization (PMF) source apportionment. The results indicate that PPDs and 6PPD-Q were detectable in 100 % of the winter PM2.5 samples, and the concentration ranges of PPDs and 6PPD-Q are 15.6-2.92 × 103 pg·m-3 and 3.90-27.4 pg·m-3, respectively, in which 6PPD and DNPD are the main compounds. Moreover, a competitive formation mechanism between sulfate, nitrate, ammonium (SNA) and 6PPD-Q was observed. The source apportionment results show that the incorporation of PPDs in PMF reduced the contribution of traffic source to PM2.5 from 13.5 % to 9.5 %. In the traffic source factor profiles, the load of IPPD, CPPD, DPPD, DNPD and 6PPD reaches 91.8 %, 91.6 %, 92.9 %, 80.6 % and 87.2 %, respectively. It`s amazing that traditional markers of traffic source, which often overlap with coal burning and industrial sources, over-estimated the contribution of vehicles by one third or more. The discovery of PPDs as specific markers for vehicular emissions holds significant utility, particularly considering the growing proportion of new energy vehicles in the future. The results may prove more accurate policy implications for pollution control. SYNOPSIS: PPDs are excellent indicators of vehicle emissions, and PMF without PPDs over-estimated the contribution of traffic source to PM2.5.

9.
Sci Total Environ ; 949: 175065, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39067593

RESUMO

Quinones are organic molecules that facilitate electron-transfer reactions in terrestrial environments. The reduced forms, hydroquinones, are powerful reductants that can trigger non-enzymatic radical-based decomposition of organic matter and contaminants by simultaneous reduction of iron and oxygen. Iron oxides often occur as coatings on other minerals, thus our study investigated the reactions between the ferric oxyhydroxide (FeO(OH)) surface coatings on gibbsite (Al(OH)3) and 2,6-dimethoxy-1,4-hydroquinone (2,6-DMHQ). The main aim was to investigate the oxidation of 2,6-DMHQ and the generation ∙OH in the presence of O2 at low Fe concentrations in a novel setup that allows local structural characterization. The heterogeneous redox reactions between 2,6-DMHQ and the FeO(OH) coatings were studied at pH 5.0 as a function of the amount of Fe present on the gibbsite surfaces, including the effect of aging of the FeO(OH) coatings. The results showed that reactions between 2,6-DMHQ and FeO(OH) coated gibbsite under ambient conditions can generate substantial amounts of ·OH, comparable with amounts generated on pure ferrihydrite surfaces. The ·OH is the product of two sequential reactions: hydroquinone oxidation by O2 and degradation of the formed H2O2. The calculated rate constant of the former reaction is the same regardless of amount of FeO(OH) coating suggesting a surface catalytic process where 2,6-DMHQ is oxidized by O2 resulting in formation of H2O2. Subsequently, the observed induction period, the low Fe2+ (aq) concentrations in solution and the dependency of FeO(OH) coating amount influencing ·OH formation suggest that the pathway for ∙OH is through H2O2 decomposition by the surface sites on the FeO(OH) coating. Overall, this study shows that co-existence of oxygen, FeO(OH) and organic reductants, possibly secreted by soil microorganisms, creates favorable conditions for generation of ·OH contributing to decomposition of organic matter and organic pollutants in soil environments.

10.
Indian J Hematol Blood Transfus ; 40(3): 517-521, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39011266

RESUMO

Increased bleeding tendency is a common and challenging complication of warfarin therapy which results in extensive pharmacogenomic studies in order to develop a personalized dosing approach and minimize the risk of related side effects. Here we aimed to explore the potential role of NQO1 gene expression in warfarin response in a group of Iranian patients. We also evaluated the NQO1 promoter methylation and its association with mRNA expression. A total of 87 patients on warfarin therapy including 34 cases with drug-induced bleeding events and 53 matched controls without bleedings were included in the study. The expression of NQO1 was examined by real-time q-PCR and the methylation status of its promoter region was analyzed using methyQESD technique. There was a significant association between the reduced NQO1 gene expression and susceptibility to bleeding before (OR = 1.92, 95% CI = 1.23-3.00, p = 0.004) and following adjustment for hypertriglyceridemia (OR = 2.22, 95% CI = 1.33-3.69, p = 0.002). Furthermore, a medium negative correlation was observed between NQO1 expression and its promoter methylation (r = - 0.382, p = 0.001). The lower expression of NQO1 which partly arises from increased methylation of promoter region, may predispose warfarin treated patients to bleeding events.

11.
FEBS J ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080980

RESUMO

Pyruvate:quinone oxidoreductase (PQO) is a flavin-containing peripheral membrane enzyme catalyzing the decarboxylation of pyruvate to acetate and CO2 with quinone as an electron acceptor. Here, we investigate PQO activity in Corynebacterium glutamicum, examine purified PQO, and describe the crystal structure of the native enzyme and a truncated version. The specific PQO activity was highest in stationary phase cells grown in complex medium, lower in cells grown in complex medium containing glucose or acetate, and lowest in cells grown in minimal acetate-medium. A similar pattern with about 30-fold higher specific PQO activities was observed in C. glutamicum with plasmid-bound pqo expression under the control of the tac promoter, indicating that the differences in PQO activity are likely due to post-transcriptional control. Continuous cultivation of C. glutamicum at dilution rates between 0.05 and 0.4 h-1 revealed a negative correlation between PQO activity and growth rate. Kinetic analysis of PQO enzymes purified from cells grown in complex or in minimal acetate-medium revealed substantial differences in specific activity (72.3 vs. 11.9 U·mg protein-1) and turnover number (kcat: 440 vs. 78 s-1, respectively), suggesting post-translational modifications affecting PQO activity. Structural analysis of PQO revealed a homotetrameric arrangement very similar to the Escherichia coli pyruvate oxidase PoxB except for the C-terminal membrane binding domain, which exhibited a conformation markedly different from its PoxB counterpart. A truncated PQO variant lacking 17 C-terminal amino acids showed higher affinity to pyruvate and was independent of detergent activation, highlighting the importance of the C-terminus for enzyme activation and lipid binding.

12.
J Colloid Interface Sci ; 676: 715-725, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39059278

RESUMO

Organic molecular electrode materials are promising candidates in batteries. However, direct application of small molecule materials usually suffers from drastic capacity decay and inefficient utilization of active materials because of their high solubility in organic electrolytes and low electrical conductivity. Herein, a simple strategy is found to address the above issues through coating the small-molecule organic materials on a commercialized carbon-coated aluminum foil (CCAF) as the enhanced electrode. Both the experimental and calculation results confirm that the relatively rough carbon coating on the aluminum foil not only exhibits superior adsorption capacity of small-molecule organic electrode materials with a tight contact interface but also provides continuous electronic conduction channels for the facilitated charge transfer and accelerated reaction kinetics. In addition, the carbon coating also inhibits Al corrosion in electrochemical process. As a result, by using the tetrahydroxy quinone-fused aza-phenazine (THQAP) molecule as an example, the THQAP-CCAF electrode exhibits an excellent rate performance with a high capacity of 220 and 180 mAh g-1 at 0.1 and 2 A/g, respectively, and also a remarkable cyclability with a capacity retention of 77.3% even after 1700 cycles in sodium-ion batteries. These performances are much more superior than that of batteries with the THQAP on bare aluminum foil (THQAP-AF). This work provides a substantial step in the practical application of the small-molecule organic electrode materials for future sustainable batteries.

13.
Int J Mol Sci ; 25(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39000077

RESUMO

Alkoxyalkylation and hydroxyalkylation methods utilizing oxo-compound derivatives such as aldehydes, acetals or acetylenes and various alcohols or water are widely used tools in preparative organic chemistry to synthesize bioactive compounds, biosensors, supramolecular compounds and petrochemicals. The syntheses of such molecules of broad relevance are facilitated by acid, base or heterogenous catalysis. However, degradation of the N-analogous Mannich bases are reported to yield alkoxyalkyl derivatives via the retro-Mannich reaction. The mutual derivative of all mentioned species are quinone methides, which are reported to form under both alkoxy- and aminoalkylative conditions and via the degradation of the Mannich-products. The aim of this review is to summarize the alkoxyalkylation (most commonly alkoxymethylation) of electron-rich arenes sorted by the methods of alkoxyalkylation (direct or via retro-Mannich reaction) and the substrate arenes, such as phenolic and derived carbocycles, heterocycles and the widely examined indole derivatives.


Assuntos
Elétrons , Alquilação , Álcoois/química , Catálise , Hidrocarbonetos Aromáticos/química
14.
Sci Total Environ ; 948: 175018, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-39059665

RESUMO

The widespread occurrence and accumulation of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) and its quinone metabolite, 6PPD quinone (6PPD-Q), have been globally recognized as a critical environmental issue. However, knowledge on the adverse effects of 6PPD and 6PPD-Q on freshwater invertebrates is limited. This study investigated the effects of 6PPD and its oxidative byproduct, 6PPD-Q, on the growth and reproduction of Daphnia pulex. Through 21-day exposure experiments, we measured the uptake of 0.1, 1, and 10 µg/L 6PPD and 6PPD-Q by D. pulex and assessed the effects on growth and fecundity of D. pulex. While 6PPD and 6PPD-Q did not affect the mortality rate of D. pulex, 6PPD-Q exposure inhibited the growth of D. pulex, indicating potential ecological risks. In particular, the reproductive capacity of D. pulex remained unaffected across the tested concentrations of 6PPD and 6PPD-Q, suggesting specific toxicological pathways that warrant further investigation. This study underscored the importance of evaluating the sublethal effects of emerging contaminants such as 6PPD and 6PPD-Q on aquatic invertebrates, and highlighted the need for comprehensive risk assessments to better understand their environmental impacts.


Assuntos
Daphnia , Reprodução , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Reprodução/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Daphnia/fisiologia , Fenilenodiaminas/toxicidade , Quinonas/metabolismo , Quinonas/toxicidade , Água Doce , Cladocera/efeitos dos fármacos , Cladocera/fisiologia
15.
Food Sci Nutr ; 12(6): 4435-4442, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38873477

RESUMO

4-Hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) is a flavor compound widely found in natural products and is used in food as a flavor-enhancing agent. Quinone oxidoreductase (QOR) was verified as a key enzyme to synthesize HDMF in strawberry, while its impact on HDMF production by Zygosaccharomyces rouxii was still unknown. The QOR gene was cloned and overexpressed in Z. rouxii, and its impact on HDMF production by Z. rouxii was then further analyzed. At the same time, it is expected to obtain engineered strains of Z. rouxii with high HDMF production. The results showed that the engineered strains of Z. rouxii exhibit different levels of QOR gene expression and HDMF production; among them, the QOR6 strain exhibiting the highest gene expression level and HDMF production was named as ZrQOR. The HDMF production of the ZrQOR strain was significantly higher than that of wild-type Z. rouxii at 3 and 5 days of culture, with 1.41-fold and 1.08-fold increases, respectively. At 3 days of fermentation, the highest HDMF yield of ZrQOR strain was obtained (2.75 mg/L), 2 days ahead of the reported highest HDMF production by Z. rouxii. At 3, 5, and 7 days, QOR gene expression was 4.8-fold, 3.3-fold, and 5.6-fold higher in the ZrQOR strain than in the wild-type Z. rouxii, respectively. Therefore, overexpression of the QOR gene facilitates HDMF synthesis. The genetic stability of the 0-20 generation ZrQOR strain was stable, and there was no significant difference in colony shape, QOR expression, or HDMF production compared to the wild type. In this study, the genetic engineering Z. rouxii strain was used to improve HDMF production. This research has laid the groundwork for further industrial production of HDMF via microbial synthesis.

16.
Molecules ; 29(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38893357

RESUMO

Quinone imines are important derivatives of quinones with a wide range of applications in organic synthesis and the pharmaceutical industry. The attack of nucleophilic reagents on quinone imines tends to lead to aromatization of the quinone skeleton, resulting in both the high reactivity and the unique reactivity of quinone imines. The extreme value of quinone imines in the construction of nitrogen- or oxygen-containing heterocycles has attracted widespread attention, and remarkable advances have been reported recently. This review provides an overview of the application of quinone imines in the synthesis of cyclic compounds via the domino annulation reaction.

17.
Molecules ; 29(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38893468

RESUMO

In this paper, an interesting γ'-carbon 1,6-conjugate addition for phosphine-catalyzed α-succinimide substituted allenoates has been disclosed. A wide array of substrates was found to participate in the reaction, resulting in the production of diverse 4-diarylmethylated 3,4-disubstituted maleimides with satisfactory to outstanding yields. Furthermore, a plausible mechanism for the reaction was proposed by the investigators.

18.
J Nutr Health Aging ; 28(8): 100287, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38908296

RESUMO

OBJECTIVES: To assess the impact of medium-term supplementation with dihydrogen and pyrroloquinoline quinone (PQQ) on mitochondrial biomarkers, brain metabolism, and cognition in elderly individuals diagnosed with mild cognitive impairment. DESIGN: A parallel-group, randomized, placebo-controlled, double-blind experimental design, maintaining a 1:1 allocation ratio between the experimental group (receiving the dihydrogen-producing minerals and PQQ) and the control group (receiving the placebo) throughout the trial. SETTING AND PARTICIPANTS: Thirty-four elderly individuals with mild cognitive impairment (mean age 71.9 ± 3.8 years; 28 females) voluntarily provided written consent to participate in this trial. Participants were assigned in a double-blind parallel-group design to receive either a dihydrogen-PQQ mixture (Alpha Hope®, CalerieLife, Irvine, CA) or placebo twice daily for a 6-week intervention period. METHODS: The primary endpoint was the change in serum brain-derived neurotrophic factor (BDNF) from baseline to the 6-week follow-up; secondary outcomes included cognitive function indices, specific metabolites in brain tissue, brain oxygenation, and the prevalence and severity of side effects. Interaction effects (time vs. intervention) were evaluated using two-way ANOVA with repeated measures and Friedman's 2-way ANOVA by ranks, for normally distributed data with homogeneous variances and non-homogeneous variances, respectively. RESULTS: Dihydrogen-PQQ resulted in a significant elevation in serum BDNF levels at the six-week follow-up (P = 0.01); conversely, no changes in BDNF levels were observed in the placebo group throughout the study duration (P = 0.27). A non-significant trend in the impact of interventions on BDNF levels was observed (treatment vs. time interaction, P = 0.14), suggesting a tendency for dihydrogen-PQQ to upregulate BDNF levels compared to the placebo. A significant interaction effect was observed for the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) scores in the orientation domain (P = 0.03), indicating the superiority of dihydrogen-PQQ over placebo in enhancing this cognitive aspect. Cerebral oxygenation saturation exhibited a significant increase following the administration of the dihydrogen-PQQ mixture, from 48.4 ± 7.2% at baseline to 52.8 ± 6.6% at 6-week post-administration (P = 0.005). In addition, brain N-acetyl aspartate levels significantly increased at seven out of thirteen locations post-intervention in participants receiving the mixture (P ≤ 0.05). CONCLUSIONS: Despite the limited number of participants included in the study for interpreting clinical parameters, the dihydrogen-PQQ mixture blend shows promise as a potential dietary intervention for enhancing mental orientation and brain metabolism in individuals with age-related mild cognitive decline.

19.
J Inflamm Res ; 17: 3825-3838, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903877

RESUMO

Background: Intervertebral disc degeneration (IDD) underlies the pathogenesis of degenerative diseases of the spine; however, its exact molecular mechanism is unclear. Purpose: To explore the molecular mechanism of mechanical pressure (MP)-induced IDD and to assess the role and mechanism of Rosuvastatin (RSV) inhibits MP-induced IDD. Methods: SD rat nucleus pulposus cells (NPCs) were cultured in vitro and an apoptosis model of NPCs was constructed using MP. Proliferative activity, reactive oxygen species content, apoptosis, and wound healing were detected in each group of NPCs, respectively. The expression of relevant proteins was detected by qPCR and Western Blot techniques. 18 SD rats were randomly divided into control, pressure and RSV groups. Elisa, qPCR, Western Blot and immunohistochemical staining techniques were used to detect changes in the content of related proteins in the intervertebral discs of each group. HE staining and Modified Saffron-O and Fast Green Stain Kit were used to assess IDD in each group. Results: MP treatment at 1.0 MPa could significantly induce apoptosis of NPCs after 24 h. MP could significantly inhibit the proliferative activity and wound healing ability of NPCs, and increase the intracellular reactive oxygen species content and apoptosis rate; pretreatment with RSV could significantly activate the Nrf2/HO-1 signaling pathway and reverse the cellular damage caused by MP; when inhibit the Nrf2/HO-1 signaling pathway activation, the protective effect of RSV was reversed. In vivo MP could significantly increase the content of inflammatory factors within the IVD and promote the degradation of extracellular matrix, leading to IDD. When the intervention of RSV was employed, it could significantly activate the Nrf2/HO-1 signaling pathway and improve the above results. Conclusion: RSV may inhibit MP-induced NPCs damage and IDD by activating the Nrf2/HO-1 signaling pathway.

20.
Environ Sci Technol ; 58(23): 10275-10286, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38825773

RESUMO

The pronounced lethality of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone (6PPD-quinone or 6PPDQ) toward specific salmonids, while sparing other fish species, has received considerable attention. However, the underlying cause of this species-specific toxicity remains unresolved. This study explored 6PPDQ toxicokinetics and intestinal microbiota composition in adult zebrafish during a 14-day exposure to environmentally realistic concentrations, followed by a 7-day recovery phase. Predominant accumulation occurred in the brain, intestine, and eyes, with the lowest levels in the liver. Six metabolites were found to undergo hydroxylation, with two additionally undergoing O-sulfonation. Semiquantitative analyses revealed that the predominant metabolite featured a hydroxy group situated on the phenyl ring adjacent to the quinone. This was further validated by assessing enzyme activity and determining in silico binding interactions. Notably, the binding affinity between 6PPDQ and zebrafish phase I and II enzymes exceeded that with the corresponding coho salmon enzymes by 1.04-1.53 times, suggesting a higher potential for 6PPDQ detoxification in tolerant species. Whole-genome sequencing revealed significant increases in the genera Nocardioides and Rhodococcus after exposure to 6PPDQ. Functional annotation and pathway enrichment analyses predicted that these two genera would be responsible for the biodegradation and metabolism of xenobiotics. These findings offer crucial data for comprehending 6PPDQ-induced species-specific toxicity.


Assuntos
Biotransformação , Microbioma Gastrointestinal , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo
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