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1.
Mol Nutr Food Res ; 68(9): e2300382, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38659179

RESUMO

Gut fungi are important parts of intestinal microbes. Dietary ingredients have the potential to regulate the structure of gut fungi in different directions and modulate mycobiome composition by changing dietary patterns, which have been applied to neurological disorders. Emerging pieces of evidence have revealed the regulatory functions of gut mycobiome in gastrointestinal diseases, but the relationships between gut fungi and functional gastrointestinal disorders (FGIDs) are ignored in the past. This review discusses the impact of dietary nutrients and patterns on mycobiome, and the possible ways in which gut fungi are involved in the pathogenesis of FGIDs. Besides affecting host immunity, intestinal fungi can be involved in the pathogenesis of FGIDs by endosymbiosis or bidirectional regulation with gut bacteria as well. In addition, the Mediterranean diet may be the most appropriate dietary pattern for subjects with FGIDs. A full understanding of these associations may have important implications for the pathogenesis and treatment of FGIDs.


Assuntos
Dieta , Gastroenteropatias , Microbioma Gastrointestinal , Micobioma , Humanos , Gastroenteropatias/microbiologia , Microbioma Gastrointestinal/fisiologia , Fungos , Dieta Mediterrânea , Animais
2.
Gastroenterology ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38582270

RESUMO

BACKGROUND AND AIMS: Hepatitis E virus (HEV), primarily genotype 1 (HEV-1), causes approximately 20.1 million infections, 44,000 deaths, and 3000 stillbirths annually. Current evidence indicates that HEV-1 is only transmitted in humans. Here, we evaluated whether Mongolian gerbils can serve as animal models for HEV-1 infection. METHODS: Mongolian gerbils were used for HEV-1 and hepatitis E virus genotype 3 infection experiments. HEV infection parameters, including detection of HEV RNA and HEV antigen, liver function assessment, and histopathology, were evaluated. RESULTS: We adapted a clinical isolate of HEV-1 for Mongolian gerbils by serial passaging in feces of aged male gerbils. The gerbil-adapted strain obtained at passage 3 induced a robust, acute HEV infection, characterized by stable fecal virus shedding, elevated liver enzymes, histopathologic changes in the liver, and seroconversion to anti-HEV. An infectious complementary DNA clone of the adapted virus was generated. HEV-1-infected pregnant gerbils showed a high rate of maternal mortality and vertical transmission. HEV RNA or antigens were detected in the liver, kidney, intestine, placenta, testis, and fetus liver. Liver and placental transcriptomic analyses indicated activation of host immunity. Tacrolimus prolonged HEV-1 infection, whereas ribavirin cleared infection. The protective efficacy of a licensed HEV vaccine was validated using this model. CONCLUSIONS: HEV-1 efficiently infected Mongolian gerbils. This HEV-1 infection model will be valuable for investigating hepatitis E immunopathogenesis and evaluating vaccines and antivirals against HEV.

3.
Int J Biol Macromol ; 268(Pt 1): 131640, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38636750

RESUMO

Visceral and somatic hypersensitivity is a common cause of functional dyspepsia. Marine bioactive components have been revealed to possess numerous valuable abilities. However, as a kind of polysaccharide extracted from brown algae, the study focused on the biological properties of laminarin is still limited, especially in gastrointestinal disorders. In our study, indicators associated with visceral sensational function and gastrointestinal microecology were determined to investigate the modulatory effects of laminarin on functional dyspepsia induced by iodoacetamide. Mice with visceral hypersensitivity were orally administrated with laminarin (50 and 100 mg per kg bw) for fourteen days. The results indicated that laminarin partly alleviated the dysfunction by regulating corticosterone secretion, the expression of 5HT3 receptors at both protein and mRNA levels, and mechanical transduction through the PIEZO2-EPAC1 axis. Furthermore, laminarin administration moderated the imbalanced gut microbial profile, including modulating the abundance of Bacteroidetes and Firmicutes. Our findings revealed that laminarin may restore the overexpression of 5HT3 receptors, the abnormal mechanical transduction, and impaired gut microecology. In conclusion, we provide evidence to support the utilization of laminarin as the ingredient of complementary and alternative medicine of regulating visceral and somatic hypersensitivity.

4.
Emerg Microbes Infect ; 13(1): 2332657, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38517709

RESUMO

Globally, hepatitis E virus (HEV) infections are prevalent. The finding of high viral loads and persistent viral shedding in ejaculate suggests that HEV replicates within the human male genital tract, but its target organ is unknown and appropriate models are lacking. We aimed to determine the HEV tropism in the human testis and its potential influence on male reproductive health. We conducted an ex vivo culture of human testis explants and in vitro culture of primary human Sertoli cells. Clinically derived HEV genotype 1 (HEV1) and HEV3 virions, as well as rat-derived HEV-C1, were used for inoculation. Transcriptomic analysis was performed on testis tissues collected from tacrolimus-treated rabbits with chronic HEV3 infection. Our findings reveal that HEV3, but not HEV1 or HEV-C1, can replicate in human testis explants and primary human Sertoli cells. Tacrolimus treatment significantly enhanced the replication efficiency of HEV3 in testis explants and enabled successful HEV1 infection in Sertoli cells. HEV3 infection disrupted the secretion of several soluble factors and altered the cytokine microenvironment within primary human Sertoli cells. Finally, intratesticular transcriptomic analysis of immunocompromised rabbits with chronic HEV infection indicated downregulation of genes associated with spermatogenesis. HEV can infect the human testicular tissues and Sertoli cells, with increased replication efficiency when exposed to tacrolimus treatment. These findings shed light on how HEV may persist in the ejaculate of patients with chronic hepatitis E and provide valuable ex vivo tools for studying countermeasures.


Assuntos
Vírus da Hepatite E , Hepatite E , Células de Sertoli , Testículo , Masculino , Humanos , Células de Sertoli/virologia , Vírus da Hepatite E/genética , Vírus da Hepatite E/fisiologia , Coelhos , Testículo/virologia , Testículo/citologia , Animais , Hepatite E/virologia , Replicação Viral , Ratos , Células Cultivadas , Tacrolimo/farmacologia , Genótipo , Tropismo Viral
5.
Cell Death Discov ; 10(1): 131, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472205

RESUMO

Gefitinib is one of the most extensively utilized epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) for treating advanced lung adenocarcinoma (LUAD) patients harboring EGFR mutation. However, the emergence of drug resistance significantly compromised the clinical efficacy of EGFR-TKIs. Gaining further insights into the molecular mechanisms underlying gefitinib resistance holds promise for developing novel strategies to overcome the resistance and improve the prognosis in LUAD patients. Here, we identified that the inhibitory efficacy of gefitinib on EGFR-mutated LUAD cells was partially dependent on the induction of ferroptosis, and ferroptosis protection resulted in gefitinib resistance. Among the ferroptosis suppressors, aldo-keto reductase family 1 member C1 (AKR1C1) exhibited significant upregulation in gefitinib-resistant strains of LUAD cells and predicted poor progression-free survival (PFS) and overall survival (OS) of LUAD patients who received first-generation EGFR-TKI treatment. Knockdown of AKR1C1 partially reversed drug resistance by re-sensitizing the LUAD cells to gefitinib-mediated ferroptosis. The decreased expression of miR-338-3p contributed to the aberrant upregulation of AKR1C1 in gefitinib-resistant LUAD cells. Furthermore, upregulated long non-coding RNA (lncRNA) nuclear paraspeckle assembly transcript 1_1 (NEAT1_1) sponged miR-338-3p to neutralize its suppression on AKR1C1. Dual-luciferase reporter assay and miRNA rescue experiment confirmed the NEAT1_1/miR-338-3p/AKR1C1 axis in EGFR-mutated LUAD cells. Gain- and loss-of-function assays demonstrated that the NEAT1_1/miR-338-3p/AKR1C1 axis promoted gefitinib resistance, proliferation, migration, and invasion in LUAD cells. This study reveals the effects of NEAT1_1/miR-338-3p/AKR1C1 axis-mediated ferroptosis defence in gefitinib resistance in LUAD. Thus, targeting NEAT1_1/miR-338-3p/AKR1C1 axis might be a novel strategy for overcoming gefitinib resistance in LUAD harboring EGFR mutation.

6.
Antioxidants (Basel) ; 12(12)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38136147

RESUMO

Aflatoxin B1 (AFB1), a kind of mycotoxin, imposes acute or chronic toxicity on humans and causes great public health concerns. Chlorogenic acid (CGA), a natural phenolic substance, shows a powerful antioxidant and anti-inflammatory effect. This study was conducted to investigate the effect and mechanism of CGA on alleviating cytotoxicity induced by AFB1 in L-02 cells. The results showed that CGA (160 µM) significantly recovered cell viability and cell membrane integrity in AFB1-treated (8 µM) cells. Furthermore, it was found that CGA reduced AFB1-induced oxidative injury by neutralizing reactive oxygen species (ROS) and activating the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway. In addition, CGA showed anti-inflammatory effects as it suppressed the expression of inflammation-related genes (IL-6, IL-8, and TNF-α) and AFB1-induced noncanonical nuclear factor kappa-B (NF-κB) activation. Moreover, CGA mitigated AFB1-induced apoptosis by maintaining the mitochondrial membrane potential (MMP) and inhibiting mRNA expressions of Caspase-3, Caspase-8, Bax, and Bax/Bcl-2. These findings revealed a possible mechanism: CGA prevents AFB1-induced cytotoxicity by maintaining mitochondrial membrane potential, activating Nrf2/HO-1, and inhibiting the noncanonical NF-κB signaling pathway, which may provide a new direction for the application of CGA.

7.
Animals (Basel) ; 13(18)2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37760368

RESUMO

The objectives of the study were to screen one or several Chinese herbal extracts with good ammonia emission reduction effects using an in vitro gas production study. The study consisted of a control (without Chinese herbal extract), and 11 experimental groups with added cinnamon extract (CE), Osmanthus extract (OE), tangerine peel extract (TPE), dandelion extract (DE), Coptis chinensis extract (CCE), honeysuckle extract (HE), Pulsatilla root extract (PRE), yucca extract (YE), licorice extract (LE), Ginkgo biloba extract (GBE), or astragalus extract (AE). The results showed that HE, PRE, YE, LE, GBE, and AE significantly reduced ammonia production (p ≤ 0.05). The most significant ammonia inhibition was achieved via AE, resulting in a 26.76% reduction. In all treatments, Chinese herbal extracts had no significant effect on pH, conductivity, or uric acid, urea, and nitrate-nitrogen concentrations (p > 0.05). However, AE significantly reduced urease activity and the relative activity of uricase (p ≤ 0.05). AE significantly increased the relative abundance of Bacteroides and decreased the relative abundance of Clostridium, Desulfovibrio, and Prevotell (p ≤ 0.05). Astragalus extract inhibited ammonia emission from laying hens by changing the gut microbial community structure, reducing the relative abundance of ammonia-producing bacteria, and reducing microorganisms' uricase and urease activities.

8.
Microorganisms ; 11(8)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37630652

RESUMO

Yaks live in the harsh environment of the Qinghai-Tibet Plateau, and the cold climate causes lower growth efficiency. The aim of this experiment was to explore the effects of drinking warm water on the growth performance in yak calves and investigate the underlying physiological mechanisms. A total of 24 Datong yak calves were selected and randomly assigned into the cold water group (group C, water temperature around 0-10 °C without any heating; 58.03 ± 3.111 kg) and the warm water group (group W, water constantly heated at 2 °C; 59.62 ± 2.771 kg). After the 60-day experiment, body weight was measured, and rumen fluid and blood serum samples were collected for analysis. The results show that the body weight and average daily gain of yaks that drank warm water were higher compared to those that drank cold water (p < 0.05). The acetic, propionic, isobutyric, valeric, and isovaleric acid concentrations were higher in group W than in group C (p < 0.05). Additionally, warm water changed the ruminal microbes at different levels. At the phylum level, the relative abundance of Tenericutes, Kiritimatiellaeota, and Elusimicrobiota was higher in group C (p < 0.05). At the genus level, three genera were increased by warm water, including Ruminococcoides and Eubacteriales Family XIII. Incertae Sedis, and 12 genera were decreased, including Ruminococcus (p < 0.05). At the species level, unclassified Prevotellaceae and Ruminococcoides bili were increased by warm water compared to cold water (p < 0.05). According to the metabolomics results, metabolites, including valine, isoleucine, PC (15:0/22:2(13Z,16Z)), and LysoPC (18:0/0:0), were increased in the warm water group compared to the cold water group (p < 0.05), and were enriched in glycerophospholipid and amino acid metabolism pathways. This study analyzed the differences in ruminal microbes and metabolomes of yak calves provided with water at different temperatures and revealed the potential mechanism for better performance promoted by warm drinking water.

9.
Animals (Basel) ; 13(13)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37443871

RESUMO

This study was conducted to investigate the effects of heated water intake on the growth performance, serum biochemical indexes, apparent total tract digestibility (ATTD) of nutrients and ruminal fermentation function of yak calves in winter. A total of 24 yaks (59.09 ± 3.181 kg) were randomly selected and divided into a cold water (fluctuated with the temperature of test sites at 0-10 °C) group (CW) (58.58 ± 3.592 kg) and a heated water (20 °C) group (HW) (59.61 ± 2.772 kg). After 2 months of the experiment, body weight, serum biochemical indexes, ruminal fermentation characteristics and ATTD were measured. The results showed that drinking heated water increased (p < 0.05) the total weight gain and average daily gain of yaks compared with those drinking cold water. Heated water increased (p < 0.05) the levels of immune globulin M, interleukin-6, triiodothyronine, tetraiodothyronine and growth hormone compared with cold water. In addition, yaks drinking heated water showed higher (p < 0.05) ATTD of crude protein and ether extract, as well as increased (p < 0.05) content of total protein, albumin and urea nitrogen in serum than those drinking cold water. Compared with cold water, heated water showed increased (p < 0.05) total volatile fatty acids, acetic acid and propionic acid, and a reduced (p < 0.05) acetic acid to propionic acid ratio (p < 0.05). In conclusion, drinking heated water at 20 °C could improve performance via increasing nutrient digestibility and ruminal fermentation function in yak calves.

10.
J Gastrointest Oncol ; 14(3): 1259-1278, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37435216

RESUMO

Background: Mounting evidences indicate that circular RNAs (circRNAs) are a novel class of non-coding RNAs and play vital roles in the tumorigenesis and aggressiveness including gastric cancer (GC). Nevertheless, the precise functions and underlying mechanisms of circRNAs in GC remain largely unknown. Methods: The Gene Expression Omnibus (GEO) data set GSE163416 was analyzed to screen the key circRNAs in GC. hsa_circ_0006646 was chosen for further study. GC tissues and matched adjacent normal gastric mucosal epithelial tissues were obtained from the Fourth Hospital of Hebei Medical University. The expressions of hsa_circ_0006646 was detected using quantitative real-time polymerase chain reaction (qRT-PCR). hsa_circ_0006646 was knocked down to identify its effects on GC cells. Bioinformatics algorithms were analyzed to predict the microRNA (miRNAs) potentially sponged by hsa_circ_0006646 and its target genes. Fluorescence in situ hybridization (FISH) was conducted to determine the subcellular location of hsa_circ_0006646 and the predicted miRNA. Then, qRT-PCR, luciferase reporter assay, radioimmunoprecipitation assay, Western blotting, and miRNA rescue experiments were used to confirm the hsa_circ_0006646-related regulatory axis in GC. Cell Counting Kit-8 (CCK-8), colony formation, wound healing, and Transwell experiments were performed to determine the effect of the hsa_circ_0006646-related regulatory axis on GC cells' malignant behaviors in vitro. The xenograft tumor mouse model was established to evaluate the effect of hsa_circ_0006646 in vivo. Results: hsa_circ_0006646 exhibited a high expression in GC tissues as compared to corresponding adjacent normal gastric mucosal epithelial tissues and its high expression was positively correlated with TNM stage, lymph node invasion and poor prognosis (P<0.05). Knockdown of hsa_circ_0006646 suppressed the proliferation, colony formation, migration, and invasion in GC cells (all P<0.05). hsa_circ_0006646 upregulated high mobility group box 1 (HMGB1) by sponging miR-665 in GC cells (P<0.05). The hsa_circ_0006646-miR-665-HMGB1 axis promoted malignant behaviors and epithelial-mesenchymal transition (EMT) in GC cells by activating the Wnt/ß-catenin pathway (P<0.05). The existence of hsa_circ_0006646-miR-665-HMGB1 axis was confirmed in GC specimens (P<0.05). Consequently, down-regulated hsa_circ_0006646 inhibited the progression and EMT of GC cells in vivo (P<0.05). Conclusions: For the first time, we demonstrated that hsa_circ_0006646-miR-665-HMGB1 axis exerted its tumor-promoting effects in GC, which suggested that hsa_circ_0006646 could be potentially targeted for GC treatment.

11.
Food Funct ; 14(14): 6513-6525, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37377021

RESUMO

Gastrointestinal dysmotility is a common cause of functional dyspepsia. As two kinds of polysaccharides derived from brown algae, fucoidan and laminarin possess many physiological properties; however, their relative abilities in regulating gastrointestinal motility have not been illustrated yet. In this study, we aimed to investigate the regulatory effect of fucoidan and laminarin on functional dyspepsia mice induced by loperamide. Mice with gastrointestinal dysmotility were treated with fucoidan (100 and 200 mg per kg bw) and laminarin (50 and 100 mg per kg bw). As a result, fucoidan and laminarin reversed the dysfunction mainly through regulating gastrointestinal hormones (motilin and ghrelin), the cholinergic pathway, the total bile acid level, c-kit protein expression, and gastric smooth muscle contraction-related gene expression (ANO1 and RYR3). Moreover, fucoidan and laminarin intervention modulated the gut microbiota profile including the altered richness of Muribaculaceae, Lachnospiraceae, and Streptococcus. The results indicated that fucoidan and laminarin may restore the rhythm of the migrating motor complex and regulate gut microecology. In conclusion, we provided evidence to support that fucoidan and laminarin might have potential abilities to regulate gastrointestinal motility.


Assuntos
Dispepsia , Camundongos , Animais , Dispepsia/tratamento farmacológico , Dispepsia/metabolismo , Loperamida , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo
12.
Adv Exp Med Biol ; 1417: 171-184, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37223866

RESUMO

Animal models are one of the most important tools in the study of human hepatitis E virus (HEV) infection. They are particularly important in light of the major limitations of the cell culture system for HEV. Besides nonhuman primates, which are extremely valuable because of their susceptibility to HEV genotypes 1-4, animals like swine, rabbit, and humanized mice are also potential models for studies of pathogenesis, cross-species infection, and the molecular biology of HEV. Identification of a useful animal model for human HEV infection studies is crucial to further investigations into this ubiquitous yet poorly understood virus and facilitate the development of antiviral therapeutics and vaccines.


Assuntos
Infecção Hospitalar , Vírus da Hepatite E , Humanos , Animais , Camundongos , Coelhos , Suínos , Vírus da Hepatite E/genética , Antivirais , Modelos Animais , Biologia Molecular
13.
J Clin Gastroenterol ; 57(5): 451-458, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36867517

RESUMO

BACKGROUND AND AIM: A clear relationship of biological indexes between bile acid malabsorption (BAM) and diarrhea-predominant irritable bowel syndrome (IBS-D) has not been well analyzed. This meta-analysis aimed to establish a more convenient method to diagnose BAM in IBS-D patients by comparing the differences in biomarkers between IBS-D patients and healthy people. METHODS: Multiple databases were searched for relevant case-control studies. Indicators used to diagnose BAM included 75 Se-homocholic acid taurine (SeHCAT), 7α-hydroxy-4-cholesten-3-one(C4), fibroblast growth factor-19 and 48-hour fecal bile acid (48FBA). The rate of BAM (SeHCAT) was calculated by using a random-effect model. The levels of C4, FGF19, and 48FBA were compared, and the overall effect size was combined by a fixed effect model. RESULTS: The search strategy identified 10 relevant studies comprising 1034 IBS-D patients and 232 healthy volunteers. The pooled rate of BAM in IBS-D patients was 32% (according to SeHCAT; 95% CI: 24%-40%). The level of C4 in IBS-D patients was significantly higher than that in the control group (2.86 ng/mL; 95% CI: 1.09, 4.63); The level of FGF19 was significantly lower than that in the control group (-33.97 pg/mL; 95% CI: -51.13, -16.82); The level of 48FBA was significantly higher than that in the control group (0.059; 95% CI: 0.41, 0.77). CONCLUSIONS: The results mainly concluded serum C4 and FGF19 levels in IBS-D patients. Most of the studies have different normal cutoff points of serum C4 and FGF19 levels; the performance of each test should be further estimated. By comparing the levels of these biomarkers, BAM in patients with IBS-D could be identified more accurately, which would lead to more effective treatment.


Assuntos
Síndrome do Intestino Irritável , Síndromes de Malabsorção , Humanos , Síndrome do Intestino Irritável/diagnóstico , Diarreia/etiologia , Ácidos e Sais Biliares , Síndromes de Malabsorção/diagnóstico , Síndromes de Malabsorção/etiologia , Biomarcadores
14.
Mol Nutr Food Res ; 67(9): e2200793, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36852548

RESUMO

Capsaicin, the principal spicy component of red pepper, shows numerous bioactivities these years. Based on the results of past studies, capsaicin may have potential effects on the treatment of functional dyspepsia (FD). However, most studies mainly investigate functional dyspepsia-treatment effects of capsaicin by discussing the relationship between capsaicin and transient receptor potential vanilloid type 1 (TRPV1). In fact, capsaicin may relieve the symptoms of FD in various ways. These effects involve desensitizing C nociceptive fibers, regulating kinds of neurotransmitters, counteracting viruses and inflammation, balancing the gut microbiota, inhibiting the secretion of gastric acid, and reducing oxidative stress damage. A full understanding of these mechanisms will help further development and utilization of capsaicin in food and medical fields.


Assuntos
Capsicum , Dispepsia , Capsaicina/farmacologia , Capsaicina/uso terapêutico , Dispepsia/tratamento farmacológico , Dispepsia/diagnóstico , Especiarias , Canais de Cátion TRPV
15.
J Med Virol ; 95(1): e28193, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36202778

RESUMO

An important goal of the Hepatitis E virus (HEV) vaccine is to prevent adverse pregnancy outcomes caused by different HEV genotypes during pregnancy, but studies directly evaluating maternal vaccination for HEV are lacking. Here we report maternal vaccination using HEV 239 vaccine in a pregnant rabbit model. Two dose of accelerated vaccination schedule (0, 7 days) induced high titers of anti-HEV protective antibodies in a short period of time in pregnant rabbits, which could protect the pregnant rabbits from HEV infection and adverse pregnancy outcomes. In addition, the immunized rabbits transfer maternal antibodies to pups through the placenta and breast milk, which protect neonates against HEV infection. Our results suggest that, besides vaccinating nonpregnant individuals, HEV 239 vaccine may also be discreetly considered for maternal vaccination.


Assuntos
Vírus da Hepatite E , Hepatite E , Gravidez , Animais , Feminino , Coelhos , Anticorpos Anti-Hepatite , Vacinação/métodos , Resultado da Gravidez
16.
J Integr Plant Biol ; 64(11): 2047-2059, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36165344

RESUMO

Double fertilization is an innovative phenomenon in angiosperms, in which one sperm cell first fuses with the egg cell to produce the embryo, and then the other sperm fuses with the central cell to produce the endosperm. However, the molecular mechanism of the preferential fertilization of egg cells is poorly understood. In this study, we report that two egg cell-secreted aspartic proteases, ECS1 and ECS2, play an important role in promoting preferential fertilization of egg cells in Arabidopsis. We show that simultaneous loss of ECS1 and ECS2 function resulted in an approximately 20% reduction in fertility, which can be complemented by the full-length ECS1/2 but not by corresponding active site mutants or by secretion-defective versions of ECS1/2. Detailed phenotypic analysis revealed that the egg cell-sperm cell attachment was compromised in ecs1 ecs2 siliques. Limited pollination assays with cyclin-dependent kinase a1 (cdka;1) pollen showed that preferential egg cell fertilization was impaired in the ecs1 ecs2 mutant. Taken together, these results demonstrate that egg cells secret two aspartic proteases, ECS1 and ECS2, to facilitate the attachment of sperm cells to egg cells so that preferential fertilization of egg cells is achieved. This study reveals the molecular mechanism of preferential fertilization in Arabidopsis thaliana.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Peptídeo Hidrolases , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fertilização/genética , Células Germinativas , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Mutação
17.
Hepatology ; 76(3): 788-802, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35278241

RESUMO

BACKGROUND AND AIMS: HEV infection can lead to chronicity and rapid progression to liver fibrosis and cirrhosis in immunocompromised organ transplant recipients. Robust animal models are urgently needed to study the pathogenesis and test the efficacy of vaccines and antiviral drugs in immunosuppressed settings. APPROACH AND RESULTS: Cyclosporin A was used to induce immunosuppression. Rabbits were challenged with genotype 3 or 4 HEV (i.e., the rabbit-derived HEV3 and human-derived HEV3 or HEV4). We assessed HEV markers within 13 weeks post inoculation (wpi) and pathological changes by hematoxylin and eosin and Masson staining at 4, 8, or 13 wpi. Chronic HEV infection was successfully established in immunocompromised rabbits. HEV RNA and/or antigens were detected in the liver, kidney, intestine, urine, and cerebrospinal fluid samples. Chronically infected animals exhibited typical characteristics of liver fibrosis development. Intrahepatic transcriptomic analysis indicated activation of both innate and adaptive immunity. Establishment of HEV chronicity likely contributed to the inhibited T-cell immune response. Ribavirin is effective in clearing HEV infection in immunocompromised rabbits. Most interestingly, vaccination completed before immunosuppression conferred full protection against both HEV3 and HEV4 infections, but vaccination during immunosuppression was only partially protective, and the efficacy did not improve with increased or additional vaccine doses. CONCLUSIONS: The immunocompromised rabbit model of both chronic HEV3 and HEV4 infection that was established captured the key features of chronic HEV infection in transplant patients, including liver fibrogenesis, and revealed the distinct effectiveness of vaccination administered before or under immunosuppression. This rabbit model is valuable for understanding the pathogenesis of chronic hepatitis E, as well as for evaluating antiviral agents and vaccines.


Assuntos
Vírus da Hepatite E , Hepatite E , Animais , Antivirais/uso terapêutico , Vírus da Hepatite E/genética , Humanos , Hospedeiro Imunocomprometido , Cirrose Hepática/tratamento farmacológico , RNA Viral/genética , Coelhos , Vacinação
18.
Cell Death Discov ; 8(1): 60, 2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35149697

RESUMO

Epithelial ovarian cancer (EOC) is one of the most frequent and fatal gynecologic malignant tumors resulting in an unsatisfying prognosis. Long non-coding RNAs (lncRNAs) play pivotal roles in the tumorigenesis and progression of EOC. However, the profile of lncRNAs involved in EOC remains to be expanded to further improve clinical treatment strategy. In present study, we identified a novel tumor-suppressive lncRNA small nucleolar RNA host gene 10 (SNHG10) in EOC. Kaplan-Meier analysis and COX proportional hazard progression model showed that low expression of SNHG10 was correlated with a poor prognosis of EOC patients. Overexpressing SNHG10 suppressed the proliferation, colony formation, migration, and invasion of EOC cells. Furthermore, SNHG10 was predicted to sponge miR-200a-3p in EOC cells according to the LncBase v.2 experimental module. Then, the binding of SNHG10 and miR-200a-3p was confirmed by performing quantitative real-time PCR (qRT-PCR) and luciferase reporter assays. RNA immunoprecipitation (RIP) showed that SNHG10 and miR-200a-3p occupied the same Ago2 protein to form an RNA-induced silencing complex (RISC). By overlapping the results from the bioinformatics algorithms, tumor-suppressor bridging integrator-1 (BIN1) was found to be a main downstream target of the SNHG10/miR-200a-3p axis. Low expression of BIN1 in EOC tissues was detected by using immunohistochemistry (IHC). Besides, BIN1 and SNHG10 expression was positively correlated in EOC tissues. By performing miRNA rescue experiments, a SNHG10/miR-200a-3p/BIN1 axis and its promoting effects on malignant behaviors and epithelial-mesenchymal transition (EMT) process were verified in EOC cells. Moreover, SNHG10 overexpression significantly suppressed the tumorigenesis and EMT of EOC cells in vivo. Altogether, SNHG10 sponges miR-200a-3p to upregulate BIN1 and thereby exerting its tumor-suppressive effects in EOC. Therefore, the SNHG10/miR-200a-3p/BIN1 axis may act as a potential predictive biomarker and therapeutic target for treating EOC.

19.
Science ; 375(6578): 290-296, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35050671

RESUMO

Fertilization of an egg by multiple sperm (polyspermy) leads to lethal genome imbalance and chromosome segregation defects. In Arabidopsis thaliana, the block to polyspermy is facilitated by a mechanism that prevents polytubey (the arrival of multiple pollen tubes to one ovule). We show here that FERONIA, ANJEA, and HERCULES RECEPTOR KINASE 1 receptor-like kinases located at the septum interact with pollen tube-specific RALF6, 7, 16, 36, and 37 peptide ligands to establish this polytubey block. The same combination of RALF (rapid alkalinization factor) peptides and receptor complexes controls pollen tube reception and rupture inside the targeted ovule. Pollen tube rupture releases the polytubey block at the septum, which allows the emergence of secondary pollen tubes upon fertilization failure. Thus, orchestrated steps in the fertilization process in Arabidopsis are coordinated by the same signaling components to guarantee and optimize reproductive success.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Peptídeos/metabolismo , Tubo Polínico/fisiologia , Transdução de Sinais , Fertilização , Ligantes , Óvulo Vegetal/fisiologia , Fosfotransferases/metabolismo , Pólen/metabolismo , Tubo Polínico/metabolismo , Polinização , Proteínas Quinases/metabolismo
20.
Front Plant Sci ; 13: 1091620, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36714734

RESUMO

Two-component system (TCS), which comprises histidine kinases (HKs), histidine phosphotransfer proteins (HPs), and response regulators (RRs), plays essential roles in regulating plant growth, development, and response to various environmental stimuli. TCS genes have been comprehensively identified in various plants, while studies on the genome-wide identification and analysis of TCS in sweet potato were still not reported. Therefore, in this study, a total of 90 TCS members consisting of 20 HK(L)s, 11 HPs, and 59 RRs were identified in the genome of Ipomoea batatas. Furthermore, their gene structures, conserved domains, and phylogenetic relationships were analyzed in detail. Additionally, the gene expression profiles in various organs were analyzed, and response patterns to adverse environmental stresses were investigated. The results showed that these 90 TCS genes were mapped on 15 chromosomes with a notably uneven distribution, and the expansion of TCS genes in sweet potato was attributed to both segmental and tandem duplications. The majority of the TCS genes showed distinct organ-specific expression profiles, especially in three types of roots (stem roots, fibrous roots, tuberous roots). Moreover, most of the TCS genes were either induced or suppressed upon treatment with abiotic stresses (drought, salinity, cold, heat) and exogenous phytohormone abscisic acid (ABA). In addition, the yeast-two hybrid system was used to reveal the HK-HP-RR protein-protein interactions. IbHP1, IbHP2, IbHP4, and IbHP5 could interact with three HKs (IbHK1a, IbHK1b, and IbHK5), and also interact with majority of the type-B RRs (IbRR20-IbRR28), while no interaction affinity was detected for IbHP3. Our systematic analyses could provide insights into the characterization of the TCS genes, and further the development of functional studies in sweet potato.

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