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Regenerated cellulose (RC) films are considered a sustainable packaging material that can replace non-degradable petroleum-based plastics. However, their susceptibility to water vapor and oxygen can limit their effectiveness in protecting products. This study introduces a novel approach for enhancing RC films to create durable, flexible, hydrophobic, high-barrier, and biodegradable packaging materials. By exploring the impact of ascorbic acid coagulation bath treatment and plasma-enhanced chemical vapor deposition (PECVD) on the properties of RC films, we found that the coagulation bath treatment facilitated the organized reconfiguration of cellulose chains, while PECVD applied a dense SiOx coating on the film surface. The results demonstrated a significant enhancement in water vapor and oxygen barrier properties of the composite film, almost reaching the level of commercial barrier films. Moreover, the composite film displayed exceptional biodegradability, fully degrading in soil within 35 days. Additionally, it showcased impressive mechanical strength, hydrophobic characteristics, and freshness preservation, positioning it as a valuable option for bio-based high-barrier packaging applications.
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Methamphetamine (Meth) is a potent psychostimulant with well-established hepatotoxicity. Gut microbiota-derived short-chain fatty acids (SCFAs) have been reported to yield beneficial effects on the liver. In this study, we aim to further reveal the mechanisms of Meth-induced hepatic injuries and investigate the potential protective effects of SCFAs. Herein, mice were intraperitoneally injected with 15â¯mg/kg Meth to induce hepatic injuries. The composition of fecal microbiota and SCFAs was profiled using 16â¯S rRNA sequencing and Gas Chromatography/Mass Spectrometry (GC/MS) analysis, respectively. Subsequently, SCFAs supplementation was performed to evaluate the protective effects against hepatic injuries. Additionally, Sigma-1 receptor knockout (S1R-/-) mice and fluvoxamine (Flu), an agonist of S1R, were introduced to investigate the mechanisms underlying the protective effects of SCFAs. Our results showed that Meth activated S1R and induced hepatic autophagy, inflammation, and oxidative stress by stimulating the MAPK/ERK pathway. Meanwhile, Meth disrupted SCFAs product-related microbiota, leading to a reduction in fecal SCFAs (especially Acetic acid and Propanoic acid). Accompanied by the optimization of gut microbiota, SCFAs supplementation normalized S1R expression and ameliorated Meth-induced hepatic injuries by repressing the MAPK/ERK pathway. Effectively, S1R knockout repressed Meth-induced activation of the MAPK/ERK pathway and further ameliorated hepatic injuries. Finally, the overexpression of S1R stimulated the MAPK/ERK pathway and yielded comparable adverse phenotypes to Meth administration. These findings suggest that Meth-induced hepatic injuries relied on the activation of S1R, which could be alleviated by SCFAs supplementation. Our study confirms the crucial role of S1R in Meth-induced hepatic injuries for the first time and provides a potential preemptive therapy.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Ácidos Grasos Volátiles , Microbioma Gastrointestinal , Metanfetamina , Ratones Noqueados , Receptores sigma , Receptor Sigma-1 , Metanfetamina/toxicidad , Animales , Receptores sigma/metabolismo , Ácidos Grasos Volátiles/metabolismo , Ratones , Microbioma Gastrointestinal/efectos de los fármacos , Masculino , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Hígado/efectos de los fármacos , Hígado/metabolismo , Ratones Endogámicos C57BL , Estrés Oxidativo/efectos de los fármacos , Heces/química , Heces/microbiologíaRESUMEN
Nanoplastics (NPs) pollution has become a global environmental problem, raising numerous health concerns. However, the cardiotoxicity of NPs exposure and the underlying mechanisms have been understudied to date. To address this issue, we comprehensively evaluated the cardiotoxicity of polystyrene nanoplastics (PS-NPs) in both healthy and pathological states. Briefly, mice were orally exposed to four different concentrations (0 mg/day, 0.1 mg/day, 0.5 mg/day, and 2.5 mg/day) of 100-nm PS-NPs for 6 weeks to assess their cardiotoxicity in a healthy state. Considering that individuals with underlying health conditions are more vulnerable to the adverse effects of pollution, we further investigated the cardiotoxic effects of PS-NPs on pathological states induced by isoprenaline. Results showed that PS-NPs induced cardiomyocyte apoptosis, cardiac fibrosis, and myocardial dysfunction in healthy mice and exacerbated cardiac remodeling in pathological states. RNA sequencing revealed that PS-NPs significantly upregulated homeodomain interacting protein kinase 2 (HIPK2) in the heart and activated the P53 and TGF-beta signaling pathways. Pharmacological inhibition of HIPK2 reduced P53 phosphorylation and inhibited the activation of the TGF-ß1/Smad3 pathway, which in turn decreased PS-NPs-induced cardiotoxicity. This study elucidated the potential mechanisms underlying PS-NPs-induced cardiotoxicity and underscored the importance of evaluating nanoplastics safety, particularly for individuals with pre-existing heart conditions.
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Cardiotoxicidad , Poliestirenos , Proteínas Serina-Treonina Quinasas , Proteína smad3 , Factor de Crecimiento Transformador beta1 , Proteína p53 Supresora de Tumor , Regulación hacia Arriba , Animales , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Crecimiento Transformador beta1/genética , Proteína smad3/metabolismo , Proteína smad3/genética , Cardiotoxicidad/etiología , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Poliestirenos/toxicidad , Regulación hacia Arriba/efectos de los fármacos , Masculino , Transducción de Señal/efectos de los fármacos , Ratones , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Apoptosis/efectos de los fármacos , Ratones Endogámicos C57BL , Nanopartículas/toxicidad , Miocardio/metabolismo , Miocardio/patologíaRESUMEN
Methamphetamine (METH) is a psychostimulant drug belonging to the amphetamine-type stimulant class, known to exert male reproductive toxicity. Recent studies suggest that METH can disrupt the gut microbiota. Furthermore, the gut-testis axis concept has gained attention due to the potential link between gut microbiome dysfunction and reproductive health. Nonetheless, the role of the gut microbiota in mediating the impact of METH on male reproductive toxicity remains unclear. In this study, we employed a mouse model exposed to escalating doses of METH to assess sperm quality, testicular pathology, and reproductive hormone levels. The fecal microbiota transplantation method was employed to investigate the effect of gut microbiota on male reproductive toxicity. Transcriptomic, metabolomic, and microbiological analyses were conducted to explore the damage mechanism to the male reproductive system caused by METH. We found that METH exposure led to hormonal disorders, decreased sperm quality, and changes in the gut microbiota and testicular metabolome in mice. Testicular RNA sequencing revealed enrichment of several Gene Ontology terms associated with reproductive processes, as well as PI3K-Akt signaling pathways. FMT conveyed similar reproductive damage from METH-treated mice to healthy recipient mice. The aforementioned findings suggest that the gut microbiota plays a substantial role in facilitating the reproductive toxicity caused by METH, thereby highlighting a prospective avenue for therapeutic intervention in the context of METH-induced infertility.
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Microbioma Gastrointestinal , Metanfetamina , Reproducción , Testículo , Animales , Metanfetamina/toxicidad , Masculino , Microbioma Gastrointestinal/efectos de los fármacos , Ratones , Testículo/efectos de los fármacos , Testículo/patología , Reproducción/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Ratones Endogámicos C57BL , Estimulantes del Sistema Nervioso Central/toxicidad , Trasplante de Microbiota FecalRESUMEN
Dietary pollution of Aflatoxin B1 (AFB1) poses a great threat to global food safety, which can result in serious hepatic injuries. Following the widespread use of plastic tableware, co-exposure to microplastics and AFB1 has dramatically increased. However, whether microplastics could exert synergistic effects with AFB1 and amplify its hepatotoxicity, and the underlying mechanisms are still unelucidated. Here, mice were orally exposed to 100 nm polystyrene nanoplastics (NPs) and AFB1 to investigate the influences of NPs on AFB1-induced hepatic injuries. We found that exposure to only NPs or AFB1 resulted in colonic inflammation and the impairment of the intestinal barrier, which was exacerbated by combined exposure to NPs and AFB1. Meanwhile, co-exposure to NPs exacerbated AFB1-induced dysbiosis of gut microbiota and remodeling of the fecal metabolome. Moreover, NPs and AFB1 co-exposure exhibited higher levels of systemic inflammatory factors compared to AFB1 exposure. Additionally, NPs co-exposure further exacerbated AFB1-induced hepatic fibrosis and inflammation, which could be associated with the overactivation of the TLR4/MyD88/NF-κB pathway. Notably, Spearman's correlation analysis revealed that the exacerbation of NPs co-exposure was closely associated with microbial dysbiosis. Furthermore, microbiota from NPs-exposed mice (NPsFMT) partly reproduced the exacerbation of NPs on AFB1-induced systemic and hepatic inflammation, but not fibrosis. In summary, our findings indicate that gut microbiota could be involved in the exacerbation of NPs on AFB1-induced hepatic injuries, highlighting the health risks of NPs.
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Aflatoxina B1 , Microbioma Gastrointestinal , Hígado , Microplásticos , Poliestirenos , Aflatoxina B1/toxicidad , Animales , Ratones , Microbioma Gastrointestinal/efectos de los fármacos , Poliestirenos/toxicidad , Microplásticos/toxicidad , Hígado/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas , Disbiosis/inducido químicamente , Nanopartículas/toxicidadRESUMEN
Euglena gracilis is a unicellular eukaryote between animal and plant cells, which is widely distributed in nature. E. gracilis has both plant and animal characteristics, and can grow photoautotrophically, heterotrophically and mixotrophically. E. gracilis also features on abundant and various cellular composition. Recently, extensive researches on unique cellular components of E. gracilis have revealed its application in the field of medicine, food, and feedstuff, in terms of improving immunity, fighting inflammation, and lowering uric acid levels. The application prospects of paramylon in biomedical area were also discovered. As food ingredients, food additives, feedstuffs and cosmetic ingredients, E. gracilis has been certified domestically and overseas. A series of products have been developed overseas, especially in Japan. However, the research and development of E. gracilis are still in its infancy in China, and there is huge space for development. At present, the research and potential application of cultivation and product functions of E. gracilis have been rarely reviewed. This review systematically examines both the domestic and abroad research of cultivation and production of E. gracilis, as well as the biological activity of E. gracilis powder and paramylon. The existing problems in the application, exploitation, and possible development direction of E. gracilis in the future are prospected. This review might be useful for establishing and optimizing large-scale and efficient heterotrophic technology, as well as developing related products of E. gracilis with specific functions.
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Euglena gracilis , China , Procesos HeterotróficosRESUMEN
Larch is widely distributed throughout the world and is an important species for timber supply and the extraction of industrial raw materials. In recent years, the hybrid breeding of Larix kaempferi and Larix olgensis has shown obvious heterosis in quick-growth, stress resistance and wood properties. However, its growth and development cycle is too long to meet general production needs. In order to shorten the breeding cycle, we have for the first time successfully established and optimized a somatic embryogenesis system for Larix kaempferi × Larix olgensis. We found that the highest rate of embryonal-suspensor mass (ESM) induction was observed when late cotyledonary embryos were used as explants. The induced ESMs were subjected to stable proliferation, after which abscisic acid (ABA) and polyethylene glycol (PEG) were added to successfully induce somatic embryos. Treatment with PEG and ABA was of great importance to somatic embryo formation and complemented each other's effect. ABA assisted embryo growth, whereas PEG facilitated the formation of proembryo-like structures. On top of this, we studied in more detail the relationship between redox homeostasis and the efficiency of somatic embryogenesis (frequency of ESM induction). During subculture, we observed the gradual formation of three distinct types of ESM. The Type I ESM is readily able to form somatic embryos. In contrast to type I, the type III ESM suffers from severe browning, contains a higher level of hydrogen peroxide (H2O2) and demonstrates a decreased ability to form somatic embryos. External treatment with H2O2 decreased the somatic embryogenesis efficiency of Type I and type III ESMs, or the higher the exogenous H2O2 content, the lower the resulting somatic embryogenesis efficiency. We found that treatment with the H2O2 scavenger DMTU (dimethylthiourea) could significantly increase the somatic embryogenesis efficiency of the type III ESM, as a result of a decline in endogenous H2O2 content. Overall, these findings have contributed to setting up a successful somatic embryogenesis system for larch production.
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Larix , Peróxido de Hidrógeno , Fitomejoramiento , Ácido Abscísico/farmacología , Desarrollo EmbrionarioRESUMEN
Polyethylene terephthalate (PET), primarily utilized for food and beverage packaging, consistently finds its way into the human gut, thereby exerting adverse effects on human health. PET hydrolases, critical for the degradation of PET, have been predominantly sourced from environmental microbial communities. Given the fact that the human gut harbors a vast and intricate consortium of microorganisms, inquiry into the presence of potential PET hydrolases within the human gut microbiota becomes imperative. In this investigation, we meticulously screened 22,156 homologous sequences that could potentially encode PET hydrolases using the hidden Markov model (HMM) paradigm, drawing from 4984 cultivated genomes of healthy human gut bacteria. Subsequently, we methodically validated the hydrolytic efficacy of five selected candidate PET hydrolases on both PET films and powders composed of micro-plastics (MPs). Notably, our study also unveiled the influence of both diverse PET MP powders and their resultant hydrolysates on the modulation of cytokine expression in macrophages. In summary, our research underscores the ubiquitous prevalence and considerable potential of the human gut microbiota in PET hydrolysis. Furthermore, our study significantly contributes to the holistic evaluation of the potential health hazards posed by PET MPs to human well-being.
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Prenatal exposure to methamphetamine (METH) is an issue of global concern due to its adverse effects on offspring, particularly its impact on liver health, an area still not fully understood. Inulin, a recognized prebiotic, is thought to potentially ameliorate these developmental disorders and toxic injuries in progeny. To investigate the effects of prenatal METH exposure on the liver and the role of gut microbiota, we established a murine model, the subjects of which were exposed to METH prenatally and subsequently treated with inulin. Our findings indicate that prenatal METH exposure causes liver damage in offspring, as evidenced by a decreased liver index, histopathological changes, diminished glycogen synthesis, hepatic dysfunction, and alterations in mRNA profiles. Furthermore, it impairs the antioxidant system and induces oxidative stress, possibly due to changes in cecal microbiota and dysregulation of bile acid homeostasis. However, maternal inulin supplementation appears to restore the gut microbiota in offspring and mitigate the hepatotoxic effects induced by prenatal METH exposure. Our study provides definitive evidence of METH's transgenerational hepatotoxicity and suggests that maternal inulin supplementation could be an effective preventive strategy.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Microbioma Gastrointestinal , Metanfetamina , Efectos Tardíos de la Exposición Prenatal , Embarazo , Femenino , Ratones , Animales , Humanos , Metanfetamina/toxicidad , Inulina/farmacología , Suplementos Dietéticos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & controlRESUMEN
Methamphetamine (Meth) abuse can cause serious mental disorders, including anxiety and depression. The gut microbiota is a crucial contributor to maintaining host mental health. Here, we aim to investigate if microbiota participate in Meth-induced mental disorders, and the potential mechanisms involved. Here, 15 mg/kg Meth resulted in anxiety- and depression-like behaviors of mice successfully and suppressed the Sigma-1 receptor (SIGMAR1)/BDNF/TRKB pathway in the hippocampus. Meanwhile, Meth impaired gut homeostasis by arousing the Toll-like receptor 4 (TLR4)-related colonic inflammation, disturbing the gut microbiome and reducing the microbiota-derived short-chain fatty acids (SCFAs). Moreover, fecal microbiota from Meth-administrated mice mediated the colonic inflammation and reproduced anxiety- and depression-like behaviors in recipients. Further, SCFAs supplementation optimized Meth-induced microbial dysbiosis, ameliorated colonic inflammation, and repressed anxiety- and depression-like behaviors. Finally, Sigmar1 knockout (Sigmar1-/-) repressed the BDNF/TRKB pathway and produced similar behavioral phenotypes with Meth exposure, and eliminated the anti-anxiety and -depression effects of SCFAs. The activation of SIGMAR1 with fluvoxamine attenuated Meth-induced anxiety- and depression-like behaviors. Our findings indicated that gut microbiota-derived SCFAs could optimize gut homeostasis, and ameliorate Meth-induced mental disorders in a SIGMAR1-dependent manner. This study confirms the crucial role of microbiota in Meth-related mental disorders and provides a potential preemptive therapy.
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Takotsubo syndrome (TTS) is a stress-induced cardiomyopathy that presents with sudden onset of chest pain and dyspneic and cardiac dysfunction as a result of extreme physical or emotional stress. The sigma-1 receptor (Sigmar1) is a ligand-dependent molecular chaperone that is postulated to be involved in various processes related to cardiovascular disease. However, the role of Sigmar1 in TTS remains unresolved. In this study, we established a mouse model of TTS using wild-type and Sigmar1 knockout mice to investigate the involvement of Sigmar1 in TTS development. Our results revealed that Sigmar1 knockout exacerbated cardiac dysfunction, with a noticeable decrease in ejection fraction (EF) and fractional shortening (FS) compared to the wild-type model. In terms of the gut microbiome, we observed regulation of Firmicutes and Bacteroidetes ratios; suppression of probiotic Lactobacillus growth; and a rise in pathogenic bacterial species, such as Colidextribacter. Metabolomic and transcriptomic analyses further suggested that Sigmar1 plays a role in regulating tryptophan metabolism and several signaling pathways, including MAPK, HIF-1, calcium signaling, and apoptosis pathways, which may be crucial in TTS pathogenesis. These findings offer valuable insight into the function of Sigmar1 in TTS, and this receptor may represent a promising therapeutic target for TTS.
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Introduction: Heart failure (HF) is usually the end stage of the continuum of various cardiovascular diseases. However, the mechanism underlying the progression and development of HF remains poorly understood. The sigma-1 receptor (Sigmar1) is a non-opioid transmembrane receptor implicated in many diseases, including HF. However, the role of Sigmar1 in HF has not been fully elucidated. Methods: In this study, we used isoproterenol (ISO) to induce HF in wild-type (WT) and Sigmar1 knockout (Sigmar1-/-) mice. Multi-omic analysis, including microbiomics, metabolomics and transcriptomics, was employed to comprehensively evaluate the role of Sigmar1 in HF. Results: Compared with the WT-ISO group, Sigmar1-/- aggravated ISO-induced HF, including left ventricular systolic dysfunction and ventricular remodeling. Moreover, Sigmar1-/- exacerbated ISO-induced gut microbiota dysbiosis, which was demonstrated by the lower abundance of probiotics g_Akkermansia and g_norank_f_Muribaculaceae, and higher abundance of pathogenic g_norank_f_Oscillospiraceae and Allobaculum. Furthermore, differential metabolites among WT-Control, WT-ISO and Sigmar-/--ISO groups were mainly enriched in bile secretion, tryptophan metabolism and phenylalanine metabolism, which presented a close association with microbial dysbiosis. Corresponding with the exacerbation of the microbiome, the inflammation-related NOD-like receptor signaling pathway, NF-kappa B signaling pathway and TNF signaling pathway were activated in the heart tissues. Conclusion: Taken together, this study provides evidence that a Sigmar1 knockout disturbs the gut microbiota and remodels the serum metabolome, which may exacerbate HF by stimulating heart inflammation.
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Owing to the strong C-F bond in nature and the rigidity of the poly-fluoroalkyl chain, perfluorooctanoic acid (PFOA) is difficult to be eliminated by reactive species and microbes in environments, thus posing a serious threat to ecosystems. Vitamin B12 as a cofactor for enzymes, and biochar as the electron providers and conductors, were integrated to enhance PFOA biodegradation. The raw material of biochar was the sludge after dewatering by adding 50 mg/g DS of Fe(III). After pyrolysis under high temperature (800 °C), biochar (SC800) detected high content of Fe(II) (197.64 mg/g) and abundant oxygen-containing functional groups, thus boosting PFOA biodegradation via donating electrons. 99.9% of PFOA could be removed within 60 d as 0.1 g/L SC800 was presented in the microbial systems containing vitamin B12. Moreover, vitamin B12 facilitated the evolution of Sporomusa which behaved the deflorination. Via providing reactive sites and mediating direct inter-species electron transfer (DIET), SC800 boosted PFOA biodegradation. Corresponding novel results in the present study could guide the development of bioremediation technologies for PFOA-polluted sites.
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Hierro , Aguas del Alcantarillado , Biodegradación Ambiental , Electrones , Vitamina B 12 , Ecosistema , Carbón Orgánico/química , VitaminasRESUMEN
Fibrosing interstitial lung disease (ILD) is a pathological condition that is highly heterogeneous and lethal, and has few effective treatment choices. Other than pirfenidone and nintedanib for the therapy of idiopathic pulmonary fibrosis, no medications are currently licensed for the treatment of ILD. Luteolin is a common flavonoid with multiple biological effects such as anti-inflammation but with poor solubility and absorption. In this study, we loaded luteolin into γ-cyclodextrin metal-organic frameworks (CD-MOFs) to deliver the medicine to the lungs using dry powder inhalers; in vitro pulmonary deposition results showed LUT@CDMOF had a high fine particle fraction (FPF) (59.77 ± 3.48%). LUT@CDMOF effectively inhibited ILD progression in the BLM-induced fibrosing ILD model rats. When compared to oral administration, the inhalation of LUT@CDMOF dry powder in rats showed considerable improvements in absorption and bioavailability, with a tmax of 0.08 h and a high absolute bioavailability (82%) of LUT (The AUC(0-t) and Cmax of inhal. LUT@CDMOF respectively increased about 4.03 times and 9.11 times, when compared with the i.g. LUT group). These studies demonstrate the potent anti-inflammatory activities of LUT@CDMOF. The inhaled LUT@CDMOF might be considered as a promising new strategy in the treatment of fibrosing ILD.
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To elucidate the molecular mechanisms underlying the differential metabolism of albino (white), green, and purple pericarp coloration, biochemical profiling and transcriptome sequencing analyses were performed on three different tea pericarps, Zhongbaiyihao (Camellia sinensis L. var. Zhongbai), Jinxuan (Camellia sinensis L. var. Jinxuan), and Baitangziya (Camellia sinensis L. var. Baitang). Results of biochemical analysis revealed that low chlorophyll content and low chlorophyll/carotene ratio may be the biochemical basis for albino characteristics in the 'Zhongbaiyihao' pericarp. The differentially expressed genes (DEGs) involved in anthocyanin biosynthesis, including DFR, F3'5'H, CCoAOMT, and 4-coumaroyl-CoA, were highly expressed in the purple 'Baitangziya' pericarp. In the chlorophyll synthesis of white pericarp, GUN5 (Genome Uncoupled 5) and 8-vinyl-reductase both showed high expression levels compared to the green one, which indicated that albino 'Zhongbaiyihao' pericarp had a higher chlorophyll synthesis capacity than 'Jinxuan'. Meanwhile, chlorophyllase (CLH, CSS0004684) was lower in 'Baitang' than in 'Jinxuan' and 'Zhongbaiyihao' pericarp. Among the differentially expressed transcription factors, MYB59, WRKY41-like2 (CS ng17509), bHLH62 like1 (CS ng6804), and bHLH62-like3 (CSS0039948) were downregulated in Jinxuan pericarp, suggesting that transcription factors played a role in regulating tea pericarp coloration. These findings provide a better understanding of the molecular mechanisms and theoretical basis for utilizing functional components of tea pericarp.
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Camellia sinensis , Camellia sinensis/genética , Clorofila , Perfilación de la Expresión Génica , Té/genética , Factores de TranscripciónRESUMEN
An accurate depiction of mercury (Hg) reduction is important to predict Hg biogeochemistry in both aquatic and soil systems. Although the photoreduction of Hg is well documented, reduction in the dark is poorly known and is thus the focus of this work. Black carbon (BC), an important constituent of organic matter in environments, can reduce Hg2+ in dark and oxygen-deficient conditions. Fast removal of Hg2+ in BC/Hg2+ solution was observed, with 4.99-86.88 L mg-1h-1 of the reaction rate constant, which could be ascribed to the combined actions of adsorption and reduction. Meanwhile, slow Hg reduction was obtained, compared to Hg removal, with 0.06-2.16 L mg-1h-1 of the reaction rate constant. Thus, in the initial stage, Hg2+ removal was mainly triggered by adsorption, rather than reduction. Afterward, the adsorbed Hg2+ on black carbon was converted into Hg0. Dissolved black carbon and aromatic CH on particulate black carbon were dominant triggers of Hg reduction for black carbon. During Hg reduction, the intastable intermediate, formed in the complex between aromatic CH and Hg2+, behaved as persistent free radicals, which could be detected by in situ electron paramagnetic resonance. Subsequently, the intastable intermediate was mainly converted into CO on black carbon and Hg0. Corresponding results of the present study highlight the important role of black carbon in the Hg biogeochemical cycle.
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Dietary pollution by polystyrene microplastics (MPs) can cause hepatic injuries and microbial dysbiosis. Epigallocatechin-3-gallate (EGCG), the major polyphenol in green tea, exerts beneficial effects on the liver by modulating the gut microbiota. However, the role of microbiota in MPs-induced hepatic injuries and the protective effect of EGCG have not been clarified. Here, 5 µm MPs were orally administered to mice to induce hepatic injuries. Subsequently, antibiotic cocktail (ABX) and fecal microbial transplant (FMT) experiments were performed to investigate the underlying microbial mechanisms. Additionally, EGCG was orally administered to mice to explore its protection against MPs-induced hepatic injuries. Our results showed that MPs activated systemic and hepatic inflammation, promoted fibrosis, and altered the liver metabolome; meanwhile, MPs damaged the gut homeostasis by disturbing the gut microbiome, promoting colonic inflammation, and impairing the intestinal barrier. Notably, MPs reduced the abundance of the probiotics Akkermansia, Mucispirillum, and Faecalibaculum while increasing the pathogenic Tuzzerella. Interestingly, the elimination of gut microbiota mitigated MPs-induced colonic inflammation and intestinal barrier impairment. Moreover, ABX ameliorated MPs-induced systemic and hepatic inflammation but not fibrosis. Correspondingly, microbiota from MPs-administered mice induced colonic, systemic, and hepatic inflammation, while their profibrosis effect on the liver was not observed. Finally, EGCG elevated the abundance of probiotics and effectively repressed MPs-induced colonic inflammation. MPs-induced systemic and hepatic inflammation, fibrosis, and remodeling of the liver metabolome were also attenuated by EGCG. These findings illustrated that gut microbiota contributed to MPs-induced colonic and hepatic injuries, while EGCG could serve as a potential prevention strategy for these adverse consequences.
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Microbioma Gastrointestinal , Animales , Ratones , Microplásticos , Plásticos , Poliestirenos/farmacología , InflamaciónRESUMEN
Polystyrene microplastics (PS-MPs) have emerged as a concerning pollutant in modern society due to their widespread production and usage. Despite ongoing research efforts, the impact of PS-MPs on mammalian behavior and the mechanisms driving these effects remain incompletely elucidated. Consequently, effective strategies for prevention have yet to be developed. To fill these gaps, C57BL/6 mice were orally administered with 5 µm PS-MPs for 28 consecutive days in this study. The open-field test and the elevated plus-maze test were performed to evaluate the anxiety-like behavior, 16S rRNA sequencing and untargeted metabolomics analysis were used to detect the changes of gut microbiota and serum metabolites. Our results indicated that PS-MPs exposure activated hippocampal inflammation and induced anxiety-like behavior in mice. Meanwhile, PS-MPs disturbed the gut microbiota, impaired the intestinal barrier, and aroused peripheral inflammation. Specifically, PS-MPs increased the abundance of pathogenic microbiota Tuzzerella, while lowered the abundance of probiotics Faecalibaculum and Akkermansia. Interestingly, eliminating the gut microbiota protected against the deleterious effects of PS-MPs on intestinal barrier integrity, reduced the levels of peripheral inflammatory cytokines, and ameliorated anxiety-like behavior. Additionally, green tea's primary bioactive constituent, epigallocatechin-3-gallate (EGCG), optimized gut microbial composition, improved intestinal barrier function, reduced peripheral inflammation, and exerted anti-anxiety effects by inhibiting the hippocampal TLR4/MyD88/NF-κB signaling cascade. EGCG also remodeled serum metabolism, especially modulated purine metabolism. These findings suggested that gut microbiota participates in PS-MPs-induced anxiety-like behavior by modulating the gut-brain axis, and that EGCG could serve as a potential preventive strategy.
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Microbioma Gastrointestinal , Animales , Ratones , Ratones Endogámicos C57BL , Microplásticos , Plásticos , Poliestirenos/toxicidad , ARN Ribosómico 16S , Homeostasis , Inflamación/inducido químicamente , MamíferosRESUMEN
Introduction: Burn injury has been shown to lead to changes in the composition of the gut microbiome and cause other damage in patients. However, little is known about how the gut microbial community evolves in individuals who have recovered from burn injury. Methods: In this study, we established a model of deep partial-thickness burn in mice and collected fecal samples at eight time points (pre-burn, 1, 3, 5, 7, 14, 21, and 28 days post-burn) for 16S rRNA amplification and high-throughput sequencing. Results: The results of the sequencing were analyzed using measures of alpha diversity, and beta diversity and taxonomy. We observed that the richness of the gut microbiome declined from day 7 post-burn and that the principal component and microbial community structure varied over time. On day 28 after the burn, the microbiome composition largely returned to the pre-burn level, although day 5 was a turning point for change. Some probiotics, such as the Lachnospiraceae_NK4A136_group, decreased in composition after the burn but were restored in the later recovery period. In contrast, Proteobacteria showed an opposite trend, which is known to include potential pathogenic bacteria. Conclusion: These findings demonstrate gut microbial dysbiosis after burn injury and provide new insights into the burn-related dysbiosis of the gut microbiome and strategies for improving the treatment of burn injury from the perspective of the microbiota.
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Owing to its inertness toward refractory organic pollutants and the release of Mn2+, the use of permanganate was limited in soil and groundwater remediation. The present study proposed an improvement strategy based on glucose-derived carbonaceous materials, which enhanced the potential of permanganate degrading organic pollutants. The glucose-derived carbonaceous material with 1000 °C charring temperature was named C1000, which was exploited in activating KMnO4 for the elimination of refractory organic contaminants. The addition of C1000 in the KMnO4 system triggered the degradation of refractory p-nitrophenol and quicken phenol degradation. Unlike the detection of Mn(III) species in a solo KMnO4 system, the presence of C1000 facilitated the formation of â¢OH in the KMnO4 system, which was confirmed by the use of quenchers such as methanol, benzoic acid, tertiary butanol, and carbonate. Additionally, the glucose-derived carbonaceous material played multiple roles in improving the performance of permanganate, including the enrichment of organic pollutants, donation of electrons to permanganate, and acting as an electron shuttle to facilitate the oxidation of organic pollutants by permanganate. The study's novel findings have the potential to expand the use of permanganate in the remediation of organic pollutants.