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BACKGROUND: Diabetes mellitus (DM) is a chronic metabolic disease characterized by hyperglycemia, and its increasing prevalence is a global concern. Early diagnostic markers and therapeutic targets are essential for DM prevention and treatment. Pueraria, derived from kudzu root, is used clinically for various symptoms, and its active compound, Puerarin, shows promise in improving insulin resistance and reducing inflammation. PURPOSE: This study aims to evaluate the protective effects of metformin and Puerarin at different doses in an STZ-induced DM mouse model. The intricate metabolites within the serum of STZ-induced diabetic mice were subjected to thorough investigation, thus elucidating the intricate mechanism through which Puerarin demonstrates notable efficacy in the treatment of diabetes. METHODS: An STZ-induced DM mouse model is established. Mice are treated with metformin and puerarin at varying doses. Physiological, biochemical, and histomorphological assessments are performed. Metabolomics analysis is carried out on serum samples from control, DM, metformin, and medium-dose Puerarin groups. Western blot and qRT-PCR technologies are used to validate the mechanisms. RESULTS: The DM mouse model replicates abnormal blood glucose, insulin levels, physiological, biochemical irregularities, as well as liver and pancreas damage. Treatment with metformin and Puerarin restores these abnormalities, reduces organ injury, and modulates AMPK, PPARγ, mTOR, and NF-κB protein and mRNA expression. Puerarin activates the AMPK-mTOR and PPARγ-NF-κB signaling pathways, regulating insulin signaling, glucolipid metabolism, and mitigating inflammatory damage. CONCLUSION: This study demonstrates that Puerarin has the potential to treat diabetes by modulating key signaling pathways. The focus was on the finding that Puerarin has been shown to improve insulin signaling, glucolipid metabolism and attenuate inflammatory damage through the modulation of the AMPK-mTOR and PPARγ-NF-κB pathways. The discovery of Puerarin's favorable protective effect and extremely complex mechanism highlights its prospect in the treatment of diabetes and provides theoretical support for its comprehensive development and utilization.
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Proteínas Quinases Ativadas por AMP , Glicemia , Diabetes Mellitus Experimental , Hipoglicemiantes , Isoflavonas , Metformina , NF-kappa B , PPAR gama , Pueraria , Transdução de Sinais , Serina-Treonina Quinases TOR , Animais , Isoflavonas/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , NF-kappa B/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Transdução de Sinais/efeitos dos fármacos , Masculino , Metformina/farmacologia , PPAR gama/metabolismo , Pueraria/química , Camundongos , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Metabolômica , Insulina/sangue , Insulina/metabolismoRESUMO
Siraitia grosvenorii (SG), also known as Luo Han Guo or Monk fruit, boasts a significant history in food and medicine. This review delves into SG's historical role and varied applications in traditional Chinese culture, examining its phytochemical composition and the health benefits of its bioactive compounds. It further explores SG's biological activities, including antioxidant, anti-inflammatory, and antidiabetic properties and elucidates the mechanisms behind these effects. The review also highlights recent synthetic biology advances in enhancing the production of SG's bioactive compounds, presenting new opportunities for broadening their availability. Ultimately, this review emphasizes SG's value in food and medicine, showcasing its historical and cultural importance, phytochemistry, biological functions, action mechanisms, and the role of synthetic biology in its sustainable use.
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Cucurbitaceae , Biologia Sintética , Frutas/química , Cucurbitaceae/químicaRESUMO
The meat derived from mammals such as cows, sheep, and pigs is commonly referred to as red meat. Recent studies have shown that consuming red meat can activate the immune system, produce antibodies, and subsequently develop into tumors and cancer. This is due to the presence of a potential carcinogenic compound in red meat called N-ethanol neuraminic acid (Neu5Gc). Neu5Gc is a common sialic monosaccharide in mammals, synthesized from N-acetylneuraminic acid (Neu5Ac) in the body and typically present in most mammals. However, due to the lack of the CMAH gene encoding the cytidine 5'-monophosphate Neu5Ac hydroxylase, humans are unable to synthesize Neu5Gc. Compared to primates such as mice or chimpanzees, the specific loss of Neu5Gc expression in humans is attributed to fixed genome mutations in CMAH. Although Neu5Gc cannot be produced, it can be introduced from specific dietary sources such as red meat and milk, so it is necessary to use mice or chimpanzees that knock out the CMAH gene instead of humans as experimental models. Further research has shown that early pregnancy factor (EPF) has the ability to regulate CD4+T cell-dependent immune responses. In this study, we established a simulated human animal model using C57/BL6 mice with CMAH gene knockout and analyzed the inhibitory effect of EPF on red meat Neu5Gc-induced CMAH-/- C57/BL6 mouse antibody production and chronic inflammation development. The results showed that the intervention of EPF reduced slow weight gain and shortened colon length in mice. In addition, EPF treatment significantly reduced the levels of anti Neu5Gc antibodies in the body, as well as the inflammatory factors IL-6 and IL-1ß, TNF-α and the activity of MPO. In addition, it also alleviated damage to liver and intestinal tissues and reduced the content of CD4 cells and the expression of B cell activation molecules CD80 and CD86 in mice. In summary, EPF effectively inhibited Neu5Gc-induced antibody production, reduced inflammation levels in mice, and alleviated Neu5Gc-induced inflammation. This will provide a new re-search concept and potential approach for developing immunosuppressants to address safety issues related to long-term consumption of red meat.
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Chaperonina 10 , Neoplasias , Proteínas da Gravidez , Carne Vermelha , Fatores Supressores Imunológicos , Feminino , Animais , Humanos , Camundongos , Bovinos , Suínos , Ovinos , Pan troglodytes , Formação de Anticorpos , Primatas , Inflamação , MamíferosRESUMO
N-glycolylneuraminic acid (Neu5Gc), a sialic acid predominantly found in the non-neurohumoral fluids of hind-mouthed animals, is incapable of synthesizing Neu5Gc due to a deletion in the CMAH exon of the gene encoding human CMP-Neu5Gc hydroxylase. But consumption of animal-derived foods that contain Neu5Gc, such as red meat, can instigate an immune response in humans, as Neu5Gc is recognized as a foreign substance by the human immune system. This recognition leads to the production of anti-Neu5Gc antibodies, subsequently resulting in chronic inflammation. When Neu5Gc is consumed excessively or frequently, it may contribute to the development of heart disease and cancer. This makes Neu5Gc, an endogenous pathogenic factor derived from red meat, a new hot topic in red meat safety research. In this study, aptamers obtained by the magnetic bead SELEX technique were subjected to homology and secondary structure prediction analysis as well as affinity determination. The result indicated that the aptamer 2B.N2A9 exhibited a robust binding affinity, with an affinity constant (Ka) of 1.87 × 108 L/mol. This aptamer demonstrated optimal binding specificity within a pH range of 5.4 to 7.4. Molecular docking analysis further revealed that aptamer 2B.N2A9 formed stable binding interactions with the target Neu5Gc at specific sites, namely G-14, C-15, G-13, G-58, G-60, and C-59. An Enzyme-Linked Oligonucleotide Sorbent Assay (ELOSA) methodology was established to detect the endogenous pathogenic factor Neu5Gc present in red meat. This method demonstrated a limit of detection (LOD) of 0.71 ng/mL, along with an average recovery rate of 92.23%. The aptamer obtained in this study exhibited favorable binding properties to Neu5Gc. The assay was relatively convenient and demonstrated good sensitivity. Further investigation into the distribution of Neu5Gc in various red meats is of public health significance and scientific potential. A practical detection method should be provided to guide red meat diets and ensure the nutrition and safety of meat products.
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Ácido N-Acetilneuramínico , Carne Vermelha , Animais , Humanos , Simulação de Acoplamento Molecular , Inflamação , OligonucleotídeosRESUMO
Human milk oligosaccharides (HMOs) are intricate glycans that promote healthy growth of infants and have been incorporated into infant formula as food additives. Despite their importance, the limited availability of asymmetrically branched HMOs hinders the exploration of their structure and function relationships. Herein, we report an enzymatic modular strategy for the efficient synthesis of these HMOs. The key branching enzyme for the assembly of branched HMOs, human ß1,6-N-acetylglucosaminyltransferase 2 (GCNT2), was successfully expressed in Pichia pastoris for the first time. Then, it was integrated with six other bacterial glycosyltransferases to establish seven glycosylation modules. Each module comprises a one-pot multi-enzyme (OPME) system for in-situ generation of costly sugar nucleotide donors, combined with a glycosyltransferase for specific glycosylation. This approach enabled the synthesis of 31 branched HMOs and 13 linear HMOs in a stepwise manner with well-programmed synthetic routes. The binding details of these HMOs with related glycan-binding proteins were subsequently elucidated using glycan microarray assays to provide insights into their biological functions. This comprehensive collection of synthetic HMOs not only serves as standards for HMOs structure identification in complex biological samples but also significantly enhances the fields of HMOs glycomics, opening new avenues for biomedical applications.
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Leite Humano , Oligossacarídeos , Humanos , Leite Humano/química , Oligossacarídeos/química , Glicosiltransferases/química , Glicosilação , Polissacarídeos/metabolismoRESUMO
In this study, a novel polysaccharide, AAP-2S, was extracted from Auricularia auricula, and the anti-glycosylation effect of AAP-2S and its underlying mechanisms were investigated using an in vitro BSA-fructose model and a cellular model. The results demonstrated the inhibiting formation of advanced glycation end products (AGEs) in vitro by AAP-2S. Concurrently, it attenuated oxidative damage to proteins in the model, preserved protein sulfhydryl groups from oxidation, reduced protein carbonylation, prevented structural alterations in proteins, and decreased the formation of ß-crosslinked structures. Furthermore, AAP-2S demonstrated metal-chelating capabilities. GC-MS/MS-based metabolomics were employed to analyze changes in metabolic profiles induced by AAP-2S in a CML-induced HK-2 cell model. Mechanistic investigations revealed that AAP-2S could mitigate glycosylation and ameliorate cell fibrosis by modulating the RAGE/TGF-ß/NOX4 pathway. This study provides a foundational framework for further exploration of Auricularia auricular polysaccharide as a natural anti-AGEs agent, paving the way for its potential development and application as a food additive.
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Auricularia , Reação de Maillard , Auricularia/metabolismo , Espectrometria de Massas em Tandem , Polissacarídeos/farmacologia , Proteínas , Produtos Finais de Glicação Avançada/metabolismoRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Xianglianhuazhuo formula (XLHZ) has a potential therapeutic effect on chronic atrophic gastritis (CAG). However, the specific molecular mechanism remains unclear. AIM OF THE STUDY: To evaluate the effect of XLHZ on CAG in vitro and in vivo and its potential mechanisms. METHODS: A rat model of CAG was established using a composite modeling method, and the pathological changes and ultrastructure of gastric mucosa were observed. YY1/miR-320a/TFRC and ferroptosis-related molecules were detected. An MNNG-induced gastric epithelial cell model was established in vitro to evaluate the inhibitory effect of XLHZ on cell ferroptosis by observing cell proliferation, migration, invasion, apoptosis, and molecules related to ferroptosis. The specific mechanism of action of XLHZ in treating CAG was elucidated by silencing or overexpression of targets. RESULTS: In vivo experiments showed that XLHZ could improve the pathological status and ultrastructure of gastric mucosa and inhibit ferroptosis by regulating the YY1/miR-320a/TFRC signaling pathway. The results in vitro demonstrated that transfection of miR-320a mimics inhibited cell proliferation, migration, and invasion while promoting cell apoptosis. MiR-320a targeted TFRC and inhibited ferroptosis. Overexpression of TFRC reversed the inhibitory effect of miR-320a overexpression on cell proliferation. The effect of XLHZ was consistent with that of miR-320a. YY1 targeted miR-320a, and its overexpression promoted ferroptosis. CONCLUSION: XLHZ inhibited ferroptosis by regulating the YY1/miR-320a/TFRC signaling pathway, ultimately impeding the progression of CAG.
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Ferroptose , Gastrite Atrófica , MicroRNAs , Ratos , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Gastrite Atrófica/tratamento farmacológico , Gastrite Atrófica/genética , Transdução de Sinais , Proliferação de CélulasRESUMO
Sustainable agricultural intensification could improve ecosystem service multifunctionality, yet empirical evidence remains tenuous, especially regarding consequences for spatially coupled ecosystems connected by flows across ecosystem boundaries (i.e., metaecosystems). Here we aim to understand the effects of land-use intensification on multiple ecosystem services of spatially connected grasslands and wetlands, where management practices were applied to grasslands but not directly imposed to wetlands. We synthesize long-term datasets encompassing 53 physical, chemical, and biological indicators, comprising >11,000 field measurements. Our results reveal that intensification promotes high-quality forage and livestock production in both grasslands and wetlands, but at the expense of water quality regulation, methane mitigation, non-native species invasion resistance, and biodiversity. Land-use intensification weakens relationships among ecosystem services. The effects on grasslands cascade to alter multifunctionality of embedded natural wetlands within the metaecosystems to a similar extent. These results highlight the importance of considering spatial flows of resources and organisms when studying land-use intensification effects on metaecosystems as well as when designing grassland and wetland management practices to improve landscape multifunctionality.
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Ecossistema , Pradaria , Áreas Alagadas , Biodiversidade , Agricultura/métodosRESUMO
Mammalian hibernation is composed of multiple episodes of torpor bout, separated by phases of interbout arousal. During torpor, the skeletal muscles of mammals are undoubtedly inactive, but it has been proven to mitigate disuse atrophy. While interbout arousal has been implicated in the prevention of muscle atrophy, the underlying mechanisms sustaining muscle contraction remain to be explored. In the present study, Daurian ground squirrels (Spermophilus dauricus) were divided into four groups: pre-hibernation (PRE), torpor (TOR), interbout arousal (IBA), and post-hibernation (POST). The contractile performance of slow-twitch soleus muscle (SOL) and fast-twitch extensor digitorum longus muscle (EDL) was detected both in situ and in vitro. Concurrently, mitochondrial respiratory chain complex activity in these muscles was quantified. Our findings revealed that in situ contractile properties of both muscles, including force, power output, time duration, and force development/relaxation rates of twitch contraction, and force and power output of tetanic contraction declined in the TOR group compared to the PRE group, but improved in the IBA and POST groups. Fatigue resistance of muscles, determined by the power output of repetitive tetanic contractions in situ, decreased in the TOR group but recovered in the IBA and POST groups. In vitro studies demonstrated that tetanic contraction power output in isolated muscles increased with muscle temperature in both TOR and IBA groups. However, at the same temperature, power output was consistently lower in the TOR group compared to the IBA group. Moreover, the activity of the mitochondrial respiratory chain complex, especially Complexes I and II, decreased in the TOR group but showed recovery in the IBA and POST groups. These findings suggest that both the contractile performance and fatigue resistance of mammalian skeletal muscle are compromised during torpor but can be improved during interbout arousal and post-hibernation. The rebound in body temperature and rise in mitochondrial respiratory chain complex activity in skeletal muscle are involved in enhancing contractile performance and fatigue resistance. This study suggests that interbout arousal functions as a vital temporal interval during which skeletal muscles can transition from the inactivity induced by torpor to a state of restored contractile functionality. Thus, interbout arousal serves as a behavioral safeguard against disuse-induced damage to skeletal muscles during hibernation.
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Músculo Esquelético , Sciuridae , Animais , Sciuridae/fisiologia , Músculo Esquelético/patologia , Atrofia Muscular/patologia , Contração Muscular , Nível de Alerta/fisiologiaRESUMO
Ulcerative colitis (UC) is an inflammatory bowel disease and associated with metabolic imbalance. Luteolin (LUT) reportedly exhibits anti-inflammatory activity. However, its regulatory effects on metabolites remain indistinct. Here, the effects of LUT on immune response and oxidative stress in UC were determined. Serum metabolomics profiles of UC rats treated with LUT were obtained utilizing liquid chromatography-mass spectrometry. The results revealed that LUT treatment alleviated colon tissue injury, colon shortening, weight loss, and inflammatory response in UC rats. Additionally, the levels of superoxide dismutase and total antioxidant capacity were elevated, but malondialdehyde content was reduced in serum of UC rats, while these changes were abrogated by LUT. Metabolomics analysis unveiled that l-malic acid, creatinine, l-glutamine, and l-lactic acid levels were remarkably decreased, while dimethyl sulfone, 5-methylcytosine, cysteine-S-sulfate, and jasmonic acid levels were notably increased after LUT treatment. Furthermore, differential metabolites primarily participated in d-glutamine and d-glutamate metabolism, glutathione metabolism, and citrate cycle pathways. In summary, these results demonstrated that LUT improved immune response, alleviated oxidative stress, and altered metabolites in UC rats. This study lays the root for further exploring the mechanism of LUT in the treatment of UC.
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Kiwifruit pomace is abundant in polysaccharides that exhibit diverse biological activities and prebiotic potential. This study delves into the digestive behavior and fermentation characteristics of kiwifruit pomace polysaccharides (KFP) through an in vitro simulated saliva-gastrointestinal digestion and fecal fermentation. The results reveal that following simulated digestion of KFP, its molecular weight reduced by 4.7%, and the reducing sugar (CR) increased by 9.5%. However, the monosaccharide composition and Fourier transform infrared spectroscopy characteristics showed no significant changes, suggesting that KFP remained undigested. Furthermore, even after saliva-gastrointestinal digestion, KFP retained in vitro hypolipidemic and hypoglycemic activities. Subsequently, fecal fermentation significantly altered the physicochemical properties of indigestible KFP (KFPI), particularly leading to an 89.71% reduction in CR. This indicates that gut microbiota could decompose KFPI and metabolize it into SCFAs. Moreover, after 48 h of KFPI fecal fermentation, it was observed that KFPI contributed to maintaining the balance of gut microbiota by promoting the proliferation of beneficial bacteria like Bacteroides, Lactobacillus, and Bifidobacterium, while inhibiting the unfavorable bacteria like Bilophila. In summary, this study offers a comprehensive exploration of in vitro digestion and fecal fermentation characteristics of KFP, providing valuable insights for potential development of KFP as a prebiotic for promoting intestinal health.
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Actinidia , Microbioma Gastrointestinal , Humanos , Fermentação , Digestão , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo , Fezes/microbiologia , Prebióticos , Actinidia/metabolismo , Ácidos Graxos Voláteis/metabolismoRESUMO
The key elements that influence the properties and capabilities of particulate photocatalysts are their crystallinity, size, and surface active sites. However, simultaneously controlling these three variables remains a challenge. In this study, we present the first exploration into the use of a simple ethylenediaminetetraacetate (EDTA) etching technique to decrease the particle size and increase the surface active sites of photocatalysts while preserving their high crystallinity. By employing SrTiO3 as a model photocatalyst, we were able to create an ordered step nanostructure on the surface of sintered SrTiO3. As a result of the EDTA treatment, the particle size was reduced while the crystallinity was maintained. The separation of photogenerated electrons and holes is enhanced by the combination of reduced particle size and high crystallinity. To enhance chemical reaction activities, the organized surface nano-step structures serve as high-activity sites. As a result, when subjected to simulated light irradiation, the EDTA-treated SrTiO3 samples demonstrate improved photocatalytic performance for water splitting into H2 and O2 in a stoichiometric amount that is 3.8 times greater than that of untreated SrTiO3. Since EDTA interacts with most metals, this simple EDTA etching technique has the potential to be further developed to modify additional photocatalysts with exceptional performance for a variety of applications.
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In this study, we investigated the protective effect of Astragaloside IV (Ast) on mouse podocytes and its possible mechanism of action by constructing a cadmium-induced mouse renal podocytes model. We investigated the effects of cadmium (Cd) toxicity on cell number, morphology, the mitochondrial status of subcellular organelles, protein and gene levels, and the protective effects of Ast by constructing a model of Cd-induced damage to mouse renal podocytes (MPC5) and giving Ast protection at the same time. The results showed that exposure of MPC5 cells to CdCl2 culture medium containing 6.25 µM concentration acted with low cell mortality, but the mortality of MPC5 cells increased with the prolongation of cadmium exposure time. Given Ast, the death rate in the low dose group (12.5 µM) was significantly reduced, while the death rate in the medium dose group (25 µM) was extremely significantly reduced. In comparison to the control group, the Cd-exposed group exhibited a significant increase of 166.7% in malondialdehyde (MDA) content and a significant decrease of 17.1% in SOD activity. The mitochondrial membrane potential was also reduced to varying degrees. However, in the Ast-protected group compared to the Cd-exposed group, the MDA content significantly decreased by 20.8%, the SOD activity decreased by 7.14%, and the mitochondrial membrane potential showed a significant increase. Fluorescence staining of mitochondrial membrane potential indicated that Cd exposure caused mitochondrial apoptosis. In the 12-h cadmium-exposed group, the protein expression of Nephrin in mice significantly decreased by 33.4%. However, the expression of the Desmin protein significantly increased by 67.8%, and the expression of the autophagy protein LC3-II significantly increased by 55.5%. Meanwhile, the expression of PINK1, a mitochondrial autophagy pathway protein, was significantly increased in the 12 h and 24 h cadmium exposure groups. The mRNA level of PINK1 was significantly increased, and that of Parkin was decreased in the 48 h cadmium exposure group. Compared to the Cd-exposed group, the Ast group showed more significant improvements in the expression of podocyte structure, functional proteins, and mitochondrial autophagy pathway proteins. The immunological assay of mitochondrial autophagic pathway proteins further indicated that Cd-induced damage to MPC5 cells might be associated with the dysregulation of mitochondrial autophagy.
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Cádmio , Podócitos , Camundongos , Animais , Cádmio/metabolismo , Podócitos/metabolismo , Apoptose , Superóxido Dismutase/metabolismo , Proteínas Quinases/metabolismoRESUMO
From Siraitia grosvenorii, a natural polysaccharide named SGP-1 was discovered, and its purity was determined to be 96.83%. Its structure is a glucan with 4-, 6- and 4,6-linked glucose units. In this paper, the sulfated derivative S-SGP of SGP-1 was prepared by the chlorosulfonic acid method. The sulfated derivatives were analyzed by Fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), and scanning electron microscopy (SEM). The degree of substitution (DS) of the polysaccharide is 0.62, and the weight average molecular weight (Mw) is 1.34 × 104 Da. While retaining the morphological characteristics of polysaccharides, S-SGP appeared a large number of spherical structures and strong intermolecular forces. The in vitro activity study of S-SGP showed that the sulfated derivatives had the ability to scavenge DPPH radicals, hydroxyl radicals and superoxide anions, and the scavenging power tended to increase with the increase in polysaccharide concentration. It can inhibit the growth of human hepatoma cells (HepG2), human breast cancer cells (MDA-MB-231) and human non-small cell lung cancer cells (A549) in vitro. In addition, the treatment of A549 cells with sulfuric acid derivatives can decrease the mitochondrial membrane potential, induce apoptosis, and alter the expression of apoptosis-related mRNA and protein.
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Disuse atrophy of skeletal muscle is associated with a severe imbalance in cellular Ca2+ homeostasis and marked increase in nuclear apoptosis. Nuclear Ca2+ is involved in the regulation of cellular Ca2+ homeostasis. However, it remains unclear whether nuclear Ca2+ levels change under skeletal muscle disuse conditions, and whether changes in nuclear Ca2+ levels are associated with nuclear apoptosis. In this study, changes in Ca2+ levels, Ca2+ transporters, and regulatory factors in the nucleus of hindlimb unloaded rat soleus muscle were examined to investigate the effects of disuse on nuclear Ca2+ homeostasis and apoptosis. Results showed that, after hindlimb unloading, the nuclear envelope Ca2+ levels ([Ca2+]NE) and nucleocytoplasmic Ca2+ levels ([Ca2+]NC) increased by 78% (p < 0.01) and 106% (p < 0.01), respectively. The levels of Ca2+-ATPase type 2 (Ca2+-ATPase2), Ryanodine receptor 1 (RyR1), Inositol 1,4,5-tetrakisphosphate receptor 1 (IP3R1), Cyclic ADP ribose hydrolase (CD38) and Inositol 1,4,5-tetrakisphosphate (IP3) increased by 470% (p < 0.001), 94% (p < 0.05), 170% (p < 0.001), 640% (p < 0.001) and 12% (p < 0.05), respectively, and the levels of Na+/Ca2+ exchanger 3 (NCX3), Ca2+/calmodulin dependent protein kinase II (CaMK II) and Protein kinase A (PKA) decreased by 54% (p < 0.001), 33% (p < 0.05) and 5% (p > 0.05), respectively. In addition, DNase X is mainly localized in the myonucleus and its activity is elevated after hindlimb unloading. Overall, our results suggest that enhanced Ca2+ uptake from cytoplasm is involved in the increase in [Ca2+]NE after hindlimb unloading. Moreover, the increase in [Ca2+]NC is attributed to increased Ca2+ release into nucleocytoplasm and weakened Ca2+ uptake from nucleocytoplasm. DNase X is activated due to elevated [Ca2+]NC, leading to DNA fragmentation in myonucleus, ultimately initiating myonuclear apoptosis. Nucleocytoplasmic Ca2+ overload may contribute to the increased incidence of myonuclear apoptosis in disused skeletal muscle.
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Elevação dos Membros Posteriores , Atrofia Muscular , Ratos , Animais , Elevação dos Membros Posteriores/fisiologia , Atrofia Muscular/patologia , Músculo Esquelético/metabolismo , Dano ao DNA , Desoxirribonucleases/metabolismoRESUMO
The golden needle mushroom (Flammulina velutiper) is one of the most productive mushrooms in the world. However, F. velutiper experiences continuous quality degradation in terms of changes in color and textural characteristics, loss of moisture, nutrition and flavor, and increased microbial populations due to its high respiratory activity during the postharvest phase. Postharvest preservation techniques, including physical, chemical and biological methods, play a vital role in maintaining postharvest quality and extending the shelf life of mushrooms. Therefore, in this study, the decay process of F. velutiper and the factors affecting its quality were comprehensively reviewed. Additionally, the preservation methods (e.g., low-temperature storage, packaging, plasma treatment, antimicrobial cleaning and 1-methylcyclopropene treatment) for F. velutiper used for the last 5 years were compared to provide an outlook on future research directions. Overall, this review aims to provide a reference for developing novel, green and safe preservation techniques for F. velutiper. © 2023 Society of Chemical Industry.
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Agaricales , Flammulina , Gastrópodes , Animais , Flammulina/metabolismo , Temperatura BaixaRESUMO
The king oyster mushroom (Pleurotus eryngii) is a delicious edible mushroom that is highly prized for its unique flavor and excellent medicinal properties. Its enzymes, phenolic compounds and reactive oxygen species are the keys to its browning and aging and result in its loss of nutrition and flavor. However, there is a lack of reviews on the preservation of Pl. eryngii to summarize and compare different storage and preservation methods. This paper reviews postharvest preservation techniques, including physical and chemical methods, to better understand the mechanisms of browning and the storage effects of different preservation methods, extend the storage life of mushrooms and present future perspectives on technical aspects in the storage and preservation of Pl. eryngii. This will provide important research directions for the processing and product development of this mushroom.
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The aim of this study was to prepare a film based on shiitake (Lentinus edodes) stalk polysaccharides (LEP) for mushroom preservation. The effects of different LEP concentrations on physical, mechanical, antioxidant, and antimicrobial properties of the prepared film were evaluated. Using scanning electron microscopy, it was revealed that the addition of 1.5 % LEP resulted in homogeneous distribution in the prepared film, as well as greatly improved its antimicrobial properties. Moreover, LEP film resulted in superior mushroom preservation by regulating enzyme activities related to mushroom browning and softening, thereby decaying these processes. In addition, the prepared film maintained mushroom quality by reducing the accumulation of H2O2 and activating the regulatory system against oxidative stress. Collectively, the findings of the present study highlight the potential benefits of LEP films as a strategy to improve mushroom quality and prevent post-harvest spoilage, hence constituting a novel prospect for the development of shiitake by-products.
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Cogumelos Shiitake , Peróxido de Hidrogênio , Antioxidantes/farmacologia , Polissacarídeos/farmacologiaRESUMO
All O-GalNAc glycans are derived from 8 cores with 2 or 3 monosaccharides linked via α- or ß-glycosidic bonds. While chemical and chemoenzymatic syntheses of ß-linked cores 1-4 and 6 and derived glycans have been well developed, the preparation of α-linked rare cores 5, 7, and 8 is challenging due to the presence of this 1,2-cis linkage. Meanwhile, the biosynthesis and functional roles of these structures are poorly understood. Herein, we synthesize 3 α-linked rare cores with exclusive α-configuration from a versatile precursor through multifaceted chemical modulations. Efficient regioselective α2-6sialylion of the rare cores was then achieved by Photobacterium damselae α2-6sialyltransferase-catalyzed reactions. These structures, together with ß-linked cores 1-4 and 6, and their sialylated forms, were fabricated into a comprehensive O-GalNAc core microarray to profile the binding of clinically important GalNAc-specific lectins. It is found that only Tn, (sialyl-)core 5, and core 7 are the binders of WFL, VVL, and SBA, while DBA only recognized (sialyl-)core 5, and Jacalin is the only lectin that binds core 8. In addition, activity assays of human α-N-acetylgalactosaminide α2-6sialyltransferases (ST6GalNAcTs) towards the cores suggested that ST6GalNAc1 may be involved in the biosynthesis of previously identified sialyl-core 5 and sialyl-core 8 glycans. In conclusion, we provide efficient routes to access α-linked O-GalNAc rare cores and derived structures, which are valuable tools for functional glycomics studies of mucin O-glycans.
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The intestine is considered to be a vital digestive organ to absorb nutrients and is the largest immune organ, while numerous microorganisms coexist with the host. It is well known that the complex interactions between the gut microbiota and the host's immune system inevitably affect the function of other organs, creating an "axis" between them. During the past few years, a new technique based mainly on microfluidics and cell biology has been developed to emulate the structure, function, and microenvironment of the human gut, called the "gut-on-chip". This microfluidic chip provides insight into key aspects of gut function in health and disease, such as the gut-brain axis, gut-liver axis, gut-kidney axis, and gut-lung axis. In this review, we first describe the basic theory of the gut axis and the various composition and parameter monitoring of the gut microarray systems, as well as summarize the development and emerging advances in the gut-organ-on-chip, with a focus on the host-gut flora and nutrient metabolism, and highlight their role in pathophysiological studies. In addition, this paper discusses the challenges and prospects for the current development and further use of the gut-organ-on-chip platform.