Synergistic effects of superfine grinding and high hydrostatic pressure on the contents, distribution, digestive behaviors and antioxidant activities of polyphenols in barley leaves.

Barley leaves (BLs) naturally contained abundant phenolics, most of which are hardly completely released from food matrix during gastrointestinal digestion. Superfine grinding (SFG) and high hydrostatic pressure (HHP) are generally used to treat the functional plants due to their effectiveness to cell wall-breaking and improvement of nutraceutical bioavailability. Thus, this study investigated the synergistic effects of SFG and HHP (100, 300, 500 MPa/20 min) on the bioaccessbility of typical phenolics in BLs during the simulated in-vitro digestion. The results demonstrated that the highest bioaccessbility (40.98%) was found in the ultrafine sample with HHP at 500 MPa. CLSM and SEM confirmed SFG led to microstructurally rapture of BLs. Moreover, the recovery index of ABTS radical scavenging activity and FRAP of HHP-treated ultrafine and fine BLs samples maximumly increased by 53.62% and 9.61%, respectively. This study is expecting to provide the theoretical basis to improve the consumer acceptance of BLs.

Bioactive Components of Areca Nut: An Overview of Their Positive Impacts Targeting Different Organs.

Areca catechu L. is a widely cultivated tropical crop in Southeast Asia, and its fruit, areca nut, has been consumed as a traditional Chinese medicinal material for more than 10,000 years, although it has recently attracted widespread attention due to potential hazards. Areca nut holds a significant position in traditional medicine in many areas and ranks first among the four southern medicines in China. Numerous bioactive compounds have been identified in areca nuts, including alkaloids, polyphenols, polysaccharides, and fatty acids, which exhibit diverse bioactive functions, such as anti-bacterial, deworming, anti-viral, anti-oxidant, anti-inflammatory, and anti-tumor effects. Furthermore, they also display beneficial impacts targeting the nervous, digestive, and endocrine systems. This review summarizes the pharmacological functions and underlying mechanisms of the bioactive ingredients in areca nut. This helps to ascertain the beneficial components of areca nut, discover its medicinal potential, and guide the utilization of the areca nut.

OTUD4 promotes the progression of glioblastoma by deubiquitinating CDK1 and activating MAPK signaling pathway.

Glioblastoma, IDH-Wild type (GBM, CNS WHO Grade 4) is a highly heterogeneous and aggressive primary malignant brain tumor with high morbidity, high mortality, and poor patient prognosis. The global burden of GBM is increasing notably due to limited treatment options, drug delivery problems, and the lack of characteristic molecular targets. OTU deubiquitinase 4 (OTUD4) is a potential predictive factor for several cancers such as breast cancer, liver cancer, and lung cancer. However, its function in GBM remains unknown. In this study, we found that high expression of OTUD4 is positively associated with poor prognosis in GBM patients. Moreover, we provided in vitro and in vivo evidence that OTUD4 promotes the proliferation and invasion of GBM cells. Mechanism studies showed that, on the one hand, OTUD4 directly interacts with cyclin-dependent kinase 1 (CDK1) and stabilizes CDK1 by removing its K11, K29, and K33-linked polyubiquitination. On the other hand, OTUD4 binds to fibroblast growth factor receptor 1 (FGFR1) and reduces FGFR1's K6 and K27-linked polyubiquitination, thereby indirectly stabilizing CDK1, ultimately influencing the activation of the downstream MAPK signaling pathway. Collectively, our results revealed that OTUD4 promotes GBM progression via OTUD4-CDK1-MAPK axis, and may be a prospective therapeutic target for GBM treatment.

Identification of peptides from honeybee gut symbionts as potential antimicrobial agents against Melissococcus plutonius.

Eusocial pollinators are crucial elements in global agriculture. The honeybees and bumblebees are associated with a simple yet host-restricted gut community, which protect the hosts against pathogen infections. Recent genome mining has led to the discovery of biosynthesis pathways of bioactive natural products mediating microbe-microbe interactions from the gut microbiota. Here, we investigate the diversity of biosynthetic gene clusters in the bee gut microbiota by analyzing 477 genomes from cultivated bacteria and metagenome-assembled genomes. We identify 744 biosynthetic gene clusters (BGCs) covering multiple chemical classes. While gene clusters for the post-translationally modified peptides are widely distributed in the bee guts, the distribution of the BGC classes varies significantly in different bee species among geographic locations, which is attributed to the strain-level variation of bee gut members in the chemical repertoire. Interestingly, we find that Gilliamella strains possessing a thiopeptide-like BGC show potent activity against the pathogenic Melissococcus plutonius. The spectrometry-guided genome mining reveals a RiPP-encoding BGC from Gilliamella with a 10 amino acid-long core peptide exhibiting antibacterial potentials. This study illustrates the widespread small-molecule-encoding BGCs in the bee gut symbionts and provides insights into the bacteria-derived natural products as potential antimicrobial agents against pathogenic infections.

Kuwanon H Inhibits Melanoma Growth through Cytotoxic Endoplasmic Reticulum Stress and Impaired Autophagy Flux.

Although great progress has been made recently in targeted and immune-based therapies, additional treatments are needed for most melanoma patients due to acquired chemoresistance, recurrence, or metastasis. Elevated autophagy is required for the pathogenesis of melanoma to attenuate metabolic stress, protecting cancer cells from chemotherapeutics or radiation. Thus, intervention with autophagy is a promising strategy for melanoma treatment. Here, we examined a novel antimelanoma natural compound named kuwanon H (KuH), which significantly inhibited melanoma cell growth in vitro/vivo. Mechanistically, KuH induced cytotoxic endoplasmic reticulum (ER) stress, which inhibited cell viability and induced apoptosis. Meanwhile, KuH-induced ER stress mediated autophagysome formation through the ATF4-DDIT3-TRIB3-AKT-MTOR axis. Importantly, KuH impaired autophagy flux, which contributed to the anticancer effects of KuH. Finally, our results showed that KuH enhanced the sensitivity of melanoma cells to cisplatin, both in vitro and in vivo, by impairing autophagy degradation of reactive oxygen species and damaged mitochondria. Our findings indicate that KuH is a promising candidate anticancer natural product for melanoma therapy.

Toward the bioactive potential of myricitrin in food production: state-of-the-art green extraction and trends in biosynthesis.

Myricitrin is a member of flavonols, natural phenolic compounds extracted from plant resources. It has gained great attention for various biological activities, such as anti-inflammatory, anti-cancer, anti-diabetic, as well as cardio-/neuro-/hepatoprotective activities. These effects have been demonstrated in both in vitro and in vivo models, making myricitrin a favorable candidate for the exploitation of novel functional foods with potential protective or preventive effects against diseases. This review summarized the health benefits of myricitrin and attempted to uncover its action mechanism, expecting to provide a theoretical basis for their application. Despite enormous bioactive potential of myricitrin, low production, high cost, and environmental damage caused by extracting it from plant resources greatly constrain its practical application. Fortunately, innovative, green, and sustainable extraction techniques are emerging to extract myricitrin, which function as alternatives to conventional techniques. Additionally, biosynthesis based on synthetic biology plays an essential role in industrial-scale manufacturing, which has not been reported for myricitrin exclusively. The construction of microbial cell factories is absolutely an appealing and competitive option to produce myricitrin in large-scale manufacturing. Consequently, state-of-the-art green extraction techniques and trends in biosynthesis were reviewed and discussed to endow an innovative perspective for the large-scale production of myricitrin.

From polyphenol to o-quinone: Occurrence, significance, and intervention strategies in foods and health implications.

Polyphenol oxidation is a chemical process impairing food freshness and other desirable qualities, which has become a serious problem in fruit and vegetable processing industry. It is crucial to understand the mechanisms involved in these detrimental alterations. o-Quinones are primarily generated by polyphenols with di/tri-phenolic groups through enzymatic oxidation and/or auto-oxidation. They are highly reactive species, which not only readily suffer the attack by nucleophiles but also powerfully oxidize other molecules presenting lower redox potentials via electron transfer reactions. These reactions and subsequent complicated reactions are capable of initiating quality losses in foods, such as browning, aroma loss, and nutritional decline. To attenuate these adverse influences, a variety of technologies have emerged to restrain polyphenol oxidation via governing different factors, especially polyphenol oxidases and oxygen. Despite tremendous efforts devoted, to date, the loss of food quality caused by quinones has remained a great challenge in the food processing industry. Furthermore, o-quinones are responsible for the chemopreventive effects and/or toxicity of the parent catechols on human health, the mechanisms by which are quite complex. Herein, this review focuses on the generation and reactivity of o-quinones, attempting to clarify mechanisms involved in the quality deterioration of foods and health implications for humans. Potential innovative inhibitors and technologies are also presented to intervene in o-quinone formation and subsequent reactions. In future, the feasibility of these inhibitory strategies should be evaluated, and further exploration on biological targets of o-quinones is of great necessity.

Short-term arecoline exposure affected the systemic health state of mice, in which gut microbes played an important role.

Arecoline is a critical bioactive component in areca nuts with toxicity and pharmacological activities. However, its effects on body health remain unclear. Here, we investigated the effects of arecoline on physiologic and biochemical parameters in mouse serum, liver, brain, and intestine. The effect of arecoline on gut microbiota was investigated based on shotgun metagenomic sequencing. The results showed that arecoline promoted lipid metabolism in mice, manifested as significantly reduced serum TC and TG and liver TC levels and a reduction in abdominal fat accumulation. Arecoline intake significantly modulated the neurotransmitters 5-HT and NE levels in the brain. Notably, arecoline intervention significantly increased serum IL-6 and LPS levels, leading to inflammation in the body. High-dose arecoline significantly reduced liver GSH levels and increased MDA levels, which led to oxidative stress in the liver. Arecoline intake promoted the release of intestinal IL-6 and IL-1ß, causing intestinal injury. In addition, we observed a significant response of gut microbiota to arecoline intake, reflecting significant changes in diversity and function of the gut microbes. Further mechanistic exploration suggested that arecoline intake can regulate gut microbes and ultimately affect the host's health. This study provided technical help for the pharmacochemical application and toxicity control of arecoline.

Engineered symbiotic bacteria interfering Nosema redox system inhibit microsporidia parasitism in honeybees.

Nosema ceranae is an intracellular parasite invading the midgut of honeybees, which causes serious nosemosis implicated in honeybee colony losses worldwide. The core gut microbiota is involved in protecting against parasitism, and the genetically engineering of the native gut symbionts provides a novel and efficient way to fight pathogens. Here, using laboratory-generated bees mono-associated with gut members, we find that Snodgrassella alvi inhibit microsporidia proliferation, potentially via the stimulation of host oxidant-mediated immune response. Accordingly, N. ceranae employs the thioredoxin and glutathione systems to defend against oxidative stress and maintain a balanced redox equilibrium, which is essential for the infection process. We knock down the gene expression using nanoparticle-mediated RNA interference, which targets the γ-glutamyl-cysteine synthetase and thioredoxin reductase genes of microsporidia. It significantly reduces the spore load, confirming the importance of the antioxidant mechanism for the intracellular invasion of the N. ceranae parasite. Finally, we genetically modify the symbiotic S. alvi to deliver dsRNA corresponding to the genes involved in the redox system of the microsporidia. The engineered S. alvi induces RNA interference and represses parasite gene expression, thereby inhibits the parasitism significantly. Specifically, N. ceranae is most suppressed by the recombinant strain corresponding to the glutathione synthetase or by a mixture of bacteria expressing variable dsRNA. Our findings extend our previous understanding of the protection of gut symbionts against N. ceranae and provide a symbiont-mediated RNAi system for inhibiting microsporidia infection in honeybees.

Morusinol extracted from Morus alba induces cell cycle arrest and apoptosis via inhibition of DNA damage response in melanoma by CHK1 degradation through the ubiquitin-proteasome pathway.

BACKGROUD: Flavonoids have a variety of biological activities, such as anti-inflammation, anti-tumor, anti-thrombosis and so on. Morusinol, as a novel isoprene flavonoid extracted from Morus alba root barks, has the effects of anti-arterial thrombosis and anti-inflammatory in previous studies. However, the anti-cancer mechanism of morusinol remains unclear. PURPOSE: In present study, we mainly studied the anti-tumor effect of morusinol and its mode of action in melanoma. METHODS: The anti-cancer effect of morusinol on melanoma were evaluated by using the MTT, EdU, plate clone formation and soft agar assay. Flow cytometry was used for detecting cell cycle and apoptosis. The É£-H2AX immunofluorescence and the alkaline comet assay were used to detect DNA damage and the Western blotting analysis was used to investigate the expressions of DNA-damage related proteins. Ubiquitination and turnover of CHK1 were also detected by using the immunoprecipitation assay. The cell line-derived xenograft (CDX) mouse models were used in vivo to evaluate the effect of morusinol on tumorigenicity. RESULTS: We demonstrated that morusinol not only had the ability to inhibit cell proliferation, but also induced cell cycle arrest at G0/G1 phase, caspase-dependent apoptosis and DNA damage in human melanoma cells. In addition, morusinol effectively inhibited the growth of melanoma xenografts in vivo. More strikingly, CHK1, which played an important role in maintaining the integrity of cell cycle, genomic stability and cell viability, was down-regulated in a dose- and time-dependent manner after morusinol treatment. Further research showed that CHK1 was degraded by the ubiquitin-proteasome pathway. Whereafter, morusinol-induced cell cycle arrest, apoptosis and DNA damage were partially salvaged by overexpressing CHK1 in melanoma cell lines. Herein, further experiments demonstrated that morusinol increased the sensitivity of dacarbazine (DTIC) to chemotherapy for melanoma in vitro and in vivo. CONCLUSION: Morusinol induces CHK1 degradation through the ubiquitin-proteasome pathway, thereby inducing cell cycle arrest, apoptosis and DNA damage response in melanoma. Our study firstly provided a theoretical basis for morusinol to be a candidate drug for clinical treatment of cancer, such as melanoma, alone or combinated with dacarbazine.

Acceleration effect of galacturonic acid on acrylamide generation: evidence in model reaction systems.

BACKGROUND: Acrylamide (AA) is a potential carcinogen formed in food rich in carbohydrate during heating. Recently, AA has been found in several fruit products, such as prune juice, sugarcane molasses and canned black olives. This study focused on the role of galacturonic acid (GalA), the main acid hydrolysis product of fruit pectin, in AA formation in three model systems - asparagine (Asn)/glucose (Glc), Asn/GalA, and Asn/Glc/GalA - during heating under different pH values (pH 3.8-7.8), Glc concentration (0-0.1 mol L-1 ), molar ratio of substrates (Asn/Glc = 1:1, 0.025-0.5 mol L-1 ) and temperature (120-180 °C) for 30 min, respectively. RESULTS: The results suggested that the addition of 0.1 mol L-1 GalA strongly accelerated AA formation in a manner dependent on pH value and temperature (P < 0.05). AA concentration under different Glc concentration and molar ratio of substrates suggested that GalA was more reactive than Glc when reacted with Asn. Furthermore, the Amadori rearrangement product/Schiff base/oxazolidine-5-one were identified as the intermediates formed in the Asn/GalA model system using ultra-performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry. CONCLUSION: The results suggested that Maillard reaction between Asn and GalA might contribute to AA formation. This study is significant in elucidating the contribution of interaction between components for AA formation in fruit products. © 2022 Society of Chemical Industry.

Health benefits of proanthocyanidins linking with gastrointestinal modulation: An updated review.

Proanthocyanidins (PACs) are the bioactive components naturally present in daily diet, especially in fruits and vegetables. Multiple pieces of evidence suggested that ingestion of PACs or diets full of PACs might contribute to physiological benefits, such as metabolic syndrome regulation, immune modulation, cancer prevention, and neuroprotection. Many studies stated that dysbiosis is closely linked with the abovementioned health conditions, and the extremely poor bioavailability of PACs, directly associated with the structural diversity, leads to extensively metabolized through gut microbiota (GM). GM transforms PACs into bioactive metabolites. Conversely, PACs also modulate the gut microbiome and the composition of GM. Thus, the complex bidirectional interactions between PACs and gut microbiota might help to understand the ambiguity between bioavailability and pleiotropic bioactivity. In this review, we summarize recent in vivo and in vitro studies from the aspect of intestinal function of PACs and its associated disease, as well as the underlying mechanisms.

Polyphenol mediated non-enzymatic browning and its inhibition in apple juice.

Non-enzymatic browning is a severe problem in juice industry. Here, polyphenol mediated non-enzymatic browning and its inhibition in apple juice were investigated. Epicatechin (R = -0.83), catechin (CAT, R = -0.79), chlorogenic acid (CGA, R = 0.65) and caffeic acid (CAF, R = 0.65) were strongly correlated with browning. CAT and chlorogenic acid quinone (CGAQ) decreased during storage with the fastest CAT degradation rate (kCGA-enriched = 1.97 × 10-3 mg·L-1·h-1 and kCAT-enriched = 2.09 × 10-3 mg·L-1·h-1) at the initial stage, but CGA and catechin quinone (CATQ) hardly changed. It was possible that CGAQ oxidized CAT at initial stage, leading to the generation of CATQ but less browning. Then the formed CATQ reacted with CAT through the complex reactions, leading to the accumulation of yellow polymers, which might explain why browning increased faster during the secondary and tertiary stages. In addition, glutathione could effectively inhibit browning compared to ascorbic acid and oxygen blocking methods.

Quinone-mediated non-enzymatic browning in model systems during long-term storage.

Non-enzymatic browning induced by polyphenol oxidation is an essential problem during the processing and storage of fruit and vegetable products. Here, the non-enzymatic browning mechanism between catechin (CAT), chlorogenic acid (CQA) and their corresponding quinones was investigated in model systems during the 32-d long-term storage. The results showed that CAT and catechin quinone (CATQ), which contains both A ring with a resorcinol structure and an o-diphenol B ring, are important precursors for browning, while chlorogenic acid (CQA) has a minor effect on browning. Chlorogenic acid quinone (CQAQ)-mediated CAT oxidation (kCAT-degradation = 0.0458 mol·L-1·d-1) was faster than CAT autoxidation (kCAT-degradation = 0.0006 mol·L-1·d-1), and there was no significant difference between CQAQ-mediated CAT oxidation and CATQ-mediated CQA oxidation. These indicate that CQAQ oxidizes CAT to CATQ quickly, and CATQ reacts with CAT subsequently through complex reactions to produce brown pigments in model systems during long-term storage.

Protective Effect of Rhus chinensis Mill. Fruits on 3,5-Diethoxycarbonyl-1,4-Dihydrocollidine-Induced Cholestasis in Mice via Ameliorating Oxidative Stress and Inflammation.

This study focused on the preventive effects of the extracts of Rhus chinensis Mill. (RCM) fruits on cholestasis induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) in mice. The results showed that RCM extracts could significantly ameliorate DDC-induced cholestasis via multiple mechanisms, including (1) alleviating liver damage via enhancing antioxidant capacity, such as increasing the contents of glutathione, superoxide dismutase, and catalase and inhibiting the levels of malondialdehyde; (2) preventing liver inflammation by suppressing NF-κB pathway and reducing proinflammatory cytokines secretion (e.g., tumor necrosis factor-α, interleukin-1ß, and interleukin-6); (3) inhibiting liver fibrosis and collagen deposition by regulating the expression of transforming growth factor-ß and α-smooth muscle actin; (4) modulating abnormal bile acid metabolism through increasing the expression of bile salt export pump and multidrug resistance-associated protein 2. This study was the first to elucidate the potential preventive effect of RCM extracts on DDC-induced cholestasis in mice from multiple pathways, which suggested that RCM fruits could be considered as a potential dietary supplement to prevent cholestasis.

HECTD3 regulates the tumourigenesis of glioblastoma by polyubiquitinating PARP1 and activating EGFR signalling pathway.

BACKGROUND: The E3 ubiquitin ligase HECTD3 is a homologue of the E6-related protein carboxyl terminus, which plays a crucial role in biological processes and tumourigenesis. However, the functional characterisation of HECTD3 in glioblastoma is still elusive. METHODS: Determination of the functional role of HECTD3 in glioblastoma was made by a combination of HECTD3 molecular pattern analysis from human glioblastoma databases and subcutaneous and in situ injections of tumours in mice models. RESULTS: This study reports that the DOC domain of HECTD3 interacts with the DNA binding domain of PARP1, and HECTD3 mediated the K63-linked polyubiquitination of PARP1 and stabilised the latter expression. Moreover, the Cysteine (Cys) 823 (ubiquitin-binding site) mutation of HECTD3 significantly reduced PARP1 polyubiquitination and HECTD3 was involved in the recruitment of ubiquitin-related molecules to PARP1 ubiquitin-binding sites (Lysines 209 and 221, respectively). Lastly, activation of EGFR-mediated signalling pathways by HECTD3 regulates PARP1 polyubiquitination. CONCLUSION: Our results unveil the potential role of HECTD3 in glioblastoma and strongly preconise further investigation and consider HECTD3 as a promising therapeutic marker for glioblastoma treatment.

Barley Leaf Ameliorates Citrobacter rodentium-Induced Colitis through Preventive Effects.

The incidence and prevalence of inflammatory bowel disease (IBD) have been increasing globally and progressively in recent decades. Barley leaf (BL) is a nutritional supplement that is shown to have health-promoting effects on intestinal homeostasis. Our previous study demonstrated that BL could significantly attenuate Citrobacter rodentium (CR)-induced colitis, but whether it exerts a prophylactic or therapeutic effect remains elusive. In this study, we supplemented BL before or during CR infestation to investigate which way BL acts. The results showed that BL supplementation prior to infection significantly reduced the disease activity index (DAI) score, weight loss, colon shortening, colonic wall swelling, and transmissible murine colonic hyperplasia. It significantly reduced the amount of CR in the feces and also markedly inhibited the extraintestinal transmission of CR. Meanwhile, it significantly reduced the levels and expression of tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFNγ), and interleukin-1ß (IL1ß). In addition, pretreatment with BL improved CR-induced gut microbiota dysbiosis by reducing the content of Proteobacteria, while increasing the content of Lactobacillus. In contrast, the effect of BL supplementation during infestation on the improvement of CR-induced colitis was not as good as that of pretreatment with BL. In conclusion, BL protects against CR-caused colitis in a preventive manner.