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A simultaneous application of CO 2 reduction and biomass selective oxidation within a shared photocatalytic redox system by an MoS 2 @GCN S-scheme heterojunction with rich sulfur vacancies. [Display omitted] • An Sv-rich MoS 2 @GCN S-scheme heterojunction was successfully fabricated. • CO 2 reduction and biomass refining were applied in a shared photocatalytic system. • The synergism of the Sv and S-scheme heterojunction accelerated charge transfer. • Xylonic acid and CO can be produced from liquid and gas simultaneously. Photocatalytic CO 2 reduction and biomass selective oxidation have considerable practical implications in addressing environmental challenges. However, developing efficient photocatalyst is the key to realize the mass-market applications. Herein, an MoS 2 @GCN S-scheme heterojunction, rich in sulfur vacancies (Sv), was fabricated by a dicyandiamide-blowing and calcination strategy using NH 4 Cl as the gas template. With the synergistic effects of Sv and the S-scheme charge migration mechanism, the 30%-Sv-MoS 2 @GCN demonstrated exceptional performance, showcasing a CO evolution rate of 68.3 μmol g−1 h−1 and a xylonic acid yield of 64.2%, without using any sacrificial agents. The formation of Sv was confirmed through electron paramagnetic resonance (EPR) analysis. The S-scheme charge transfer mechanism of the Sv-MoS 2 @GCN heterojunction was verified by in-situ X-ray photoelectron spectroscopy (XPS) spectra, EPR analysis, and density functional theory (DFT) calculations. This study establishes a framework for enhancing photocatalytic CO 2 reduction and biomass selective oxidation by regulating charge transfer through sensible structural design. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon nitride nanosheets ring inserted on the surface of PY53 was designed. • Lactic acid and CO can be produced from liquid and gas simultaneously. • CNs@PY53-x has good applicability for different biomass-derived feedstocks. • Lactic acid yield and CO evolution achieved 86.7% and 371.56 μmol g−1h−1. Synchronously producing gas–liquid products from biomass conversion is an effective solution for addressing global energy depletion and environmental pollution. Here, we designed an efficient photocatalyst (CNs@PY53-x) to co-produce CO and lactic acid from biomass-derived sugars. Carbon nitride nanosheets were incorporated onto the surface of PY53 using an ultrasonic-assisted self-assembly coupled with evaporation-drying strategy. The CNs@PY53-x exhibited broader visible light absorption, stronger photocurrent density, and faster separation rate of photogenerated carriers as compared with CNs or PY53. The photocatalytic performance of CNs@PY53-x correlated well with its photoelectric characterization, achieving an CO evolution rate of 371.56 μmol g−1h−1 and a lactic acid yield of 86.9% in the xylose-alkaline system. Furthermore, CNs@PY53-2 demonstrated favorable applicability with various biomass-based sugars. Poisoning experiments, coupled with electron spin resonance (ESR) characterization, revealed that the superoxide radical (O 2 −) was the primary oxidation active species during this process. This work presents a new strategy for synchronously producing gas–liquid products during biomass conversion. [ABSTRACT FROM AUTHOR]

Azobenzene (Azo) units were successfully introduced into perylene bisimide (PBI) structures in order to realize the photocontrolling of the morphology of the supramolecular assembly of PBI by a photoisomerization process. A total of three Azo-functionalized perylene bisimide derivatives (PBI1, PBI2, and PBI3) with different alkyl chain lengths were designed and synthesized by imidization of 3,4,9,10-perylene tetracarboxylic dianhydride with the corresponding amines. The structures of these compounds were characterized by proton nuclear magnetic resonance (1H NMR) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The photoisomerization behaviors of Azo units in PBIs were investigated using ultraviolet-visible (UV-VIS) absorption spectroscopy, which were obviously effected by solvents and the alkyl chain length. Furthermore, the photoisomerization of Azo units has the obviously regulatory effect on the morphology of supramolecular assembly of PBIs, especially for the medium-length alkyl chain-linked Azo-functionalized PBI derivative (PBI2). This research realized the photocontrolling of the morphology of the supramolecular assembly of PBI derivatives by photoisomerization of Azo units. [ABSTRACT FROM AUTHOR]

Ovarian aging and disease-related decline in fertility are challenging medical and economic issues with an increasing prevalence. Polyamines are a class of polycationic alkylamines widely distributed in mammals. They are small molecules essential for cell growth and development. Polyamines alleviate ovarian aging through various biological processes, including reproductive hormone synthesis, cell metabolism, programmed cell death, etc. However, an abnormal increase in polyamine levels can lead to ovarian damage and promote the development of ovarian disease. Therefore, polyamines have long been considered potential therapeutic targets for aging and disease, but their regulatory roles in the ovary deserve further investigation. This review discusses the mechanisms by which polyamines ameliorate human ovarian aging and disease through different biological processes, such as autophagy and oxidative stress, to develop safe and effective polyamine targeted therapy strategies for ovarian aging and the diseases. [ABSTRACT FROM AUTHOR]

Spermidine is a naturally occurring polyamine compound that has many biological functions, such as inducing autophagy and anti-inflammatory and anti-aging effects. Spermidine can affect follicular development and thus protect ovarian function. In this study, ICR mice were fed exogenous spermidine drinking water for three months to explore the regulation of ovarian function by spermidine. The results showed that the number of atretic follicles in the ovaries of spermidine-treated mice was significantly lower than that in the control group. Antioxidant enzyme activities (SOD, CAT, T-AOC) significantly increased, and MDA levels significantly decreased. The expression of autophagy protein (Beclin 1 and microtubule-associated protein 1 light chain 3 LC3 II/I) significantly increased, and the expression of the polyubiquitin-binding protein p62/SQSTM 1 significantly decreased. Moreover, we found 424 differentially expressed proteins (DEPs) were upregulated, and 257 were downregulated using proteomic sequencing. Gene Ontology and KEGG analyses showed that these DEPs were mainly involved in lipid metabolism, oxidative metabolism and hormone production pathways. In conclusion, spermidine protects ovarian function by reducing the number of atresia follicles and regulating the level of autophagy protein, antioxidant enzyme activity, and polyamine metabolism in mice. [ABSTRACT FROM AUTHOR]

Spermidine have been reported a role in antioxidative, antiaging, and antiinflammatory. Oxidative stress causes granulosa cell (GC) apoptosis, follicular atresia, and impairs poultry reproductive functions. Studies have found that autophagy is the protective mechanism against antioxidant stress and apoptosis in cells. However, the relationship between spermidine-induced autophagy, oxidative stress, and apoptosis in goose GCs remains unclear. In this study, we investigated the autophagy mechanism to mediate spermidine effects on the alleviation of oxidative stress and apoptosis in goose GCs. Follicular GCs were treated with spermidine combination with 3-Nitropropanoic acid (3-NPA), rapamycin (RAPA), and chloroquine (CQ) or with hydrogen peroxide, RAPA, and CQ. Spermidine upregulated the ratio of LC3-II/I, inhibited the accumulation of p62 protein, and induced autophagy. 3-NPA treatment significantly increased ROS production, MDA content, SOD activity, cleaved CASPASE-3 protein expression, and decreased BCL-2 protein expression in follicular GCs. Spermidine inhibited oxidative stress and apoptosis induced by 3-NPA. In addition, hydrogen peroxide-induced oxidative stress was inhibited by spermidine. However, the inhibitory effect of spermidine was eliminated under chloroquine. Our results demonstrated that spermidine relieved oxidative stress and apoptosis of GCs by inducing autophagy, indicating that spermidine has a great potential to maintain proteostasis and sustain granulosa cell viability in geese. [ABSTRACT FROM AUTHOR]

Oxidative stress is the major culprits responsible for ovarian dysfunction by damaging granulosa cells (GCs). Ferritin heavy chain (FHC) may participate in the regulation of ovarian function by mediating GCs apoptosis. However, the specific regulatory function of FHC in follicular GCs remains unclear. Here, 3-nitropropionic acid (3-NPA) was utilized to establish an oxidative stress model of follicular GCs of Sichuan white geese. To explore the regulatory effects of FHC on oxidative stress and apoptosis of primary GCs in geese by interfering or overexpressing FHC gene. After transfection of siRNA- FHC to GCs for 60 h, the expressions of FHC gene and protein decreased significantly (P < 0.05). After FHC overexpression for 72 h, the expressions of FHC mRNA and protein upregulated considerably (P < 0.05). The activity of GCs was impaired after interfering with FHC and 3-NPA coincubated (P < 0.05). When overexpression of FHC combined with 3-NPA treatment, the activity of GCs was remarkably enhanced (P < 0.05). After interference FHC and 3-NPA treatment, NF-κB and NRF2 gene expression decreased (P < 0.05), the intracellular reactive oxygen species (ROS) level increased greatly (P < 0.05), BCL-2 expression reduced, BAX/BCL-2 ratio intensified (P < 0.05), the mitochondrial membrane potential decreased notably (P < 0.05), and the apoptosis rate of GCs aggravated (P < 0.05). While overexpression of FHC combined with 3-NPA treatment could promote BCL-2 protein expression and reduce BAX/BCL-2 ratio, indicating that FHC regulated the mitochondrial membrane potential and apoptosis of GCs by mediating the expression of BCL-2. Taken together, our research manifested that FHC alleviated the inhibitory effect of 3-NPA on the activity of GCs. FHC knockdown could suppress the expression of NRF2 and NF-κB genes, reduce BCL-2 expression and augment BAX/BCL-2 ratio, contributing to the accumulation of ROS and jeopardizing mitochondrial membrane potential, as well as exacerbating GCs apoptosis. [ABSTRACT FROM AUTHOR]