Integrative bioinformatics analysis to screen key genes and signalling pathways related to ferroptosis in obesity.

Ferroptosis is closely associated with the development of disease in the body. However, there are few studies on ferroptosis-related genes (FRGs) in obesity. Therefore, key genes and signalling pathways related to ferroptosis in obesity were screened. Briefly, the RNA sequencing data of obesity and the non-obesity human samples and 259 FRGs were downloaded from GEO database and FerrDb database, respectively. The obesity-related module genes were firstly screened by weighted gene co-expression network analysis (WGCNA) and crossed with differentially expressed genes (DEGs) of obesity/normal samples and FRGs to obtain obesity-ferroptosis related (OFR) DEGs. Then, key genes were screened by PPI network. Next, the correlation of key genes and differential immune cells between obesity and normal samples were further explored by immune infiltration analysis. Finally, microRNA (miRNA)-messenger RNA (mRNA), transcription factor (TF)-mRNA networks and drug-gene interaction networks were constructed. As a result, 17 OFR DEGs were obtained, which mainly participated in processes such as lipid metabolism or adipocyte differentiation. The 4 key genes, STAT3, IL-6, PTGS2, and VEGFA, constituted the network. M2 macrophages, T cells CD8, mast cells activated, and T cells CD4 memory resting had significant differences between obesity and normal samples. Moreover, 51 miRNAs and 164 drugs were predicted for 4 key genes. All in all, this study has screened 4 FRGs, including IL-6, VEGFA, STAT3, and PTGS2, in obesity patients.

Promoter hypermethylation and comprehensive regulation of ncRNA lead to the down-regulation of ZNF880, providing a new insight for the therapeutics and research of colorectal cancer.

The human genome encodes more than 350 kinds of Krüppel-associated box (KRAB) domain-containing zinc-finger proteins (KZFPs), KRAB-type ZNF transcription factor family (KZNF) plays a vital role in gene regulatory networks. The KZNF family members include a large number of highly homologous genes, gene subtypes and pseudogenes, and their expression has a high degree of tissue specificity and precision. Due to the high complexity of its regulatory network, the KZNF gene family has not been researched in sufficient, and the role of its members in the occurrence of cancer is mostly unexplored. In this study, ZNF880 was significantly associated with overall survival (OS) and disease-free survival (DFS) in colorectal carcinoma (CRC) patients. Low ZNF880 expression resulted in shorter OS and DFS. Combined with Colon adenocarcinoma (COAD) and Rectum adenocarcinoma (READ) data collection in the TCGA database, we found that ZNF880 was significantly down-regulated in CRC. Further analysis of the sequence variation of ZNF880 in CRC showed that ZNF880 accumulated a large number of SNV in the C2H2 domain and KRAB domain, while promoter region of ZNF880 also showed high methylation in COAD and READ. Combined with the Cbioportal and TIMER databases, the expression of mutant ZNF880 was significantly lower in COAD compared to the wild type. Simultaneously, the lncRNA-miRNA-ZNF880 ceRNA regulatory network was constructed through co-expression and miRNAs target gene prediction, demonstrating the precision of the ZNF880 regulatory network. In addition, the decreased expression of ZNF880 caused the significant immune infiltration decreases of CD8 + cells in COAD. In contrast, the immune infiltration of CD4 + cells and macrophages in COAD is positively correlated with ZNF880. Finally, through protein-protein interaction (PPI) network analysis and transcription factor target gene prediction, we screened out the genes most likely to be related to the function of ZNF880. CENPK, IFNGR2, REC8 and ZBTB17 were identified as the most closely functioning genes with ZNF880, which may indicate that ZNF880 has important links with the formation of cell centromere, tumor immunity, cell cycle and other pathways closely related to the occurrence of CRC. These studies show that the down-regulation of ZNF880 gene is closely related to CRC, and the targeted change of the expression of its regulatory molecules (miRNA and lncRNA) may be a new perspective for CRC treatment.

Physical exercise attenuates age-related muscle atrophy and exhibits anti-ageing effects via the adiponectin receptor 1 signalling.

BACKGROUND: Although the adiponectin signalling exerts exercise-mimicking effects, whether this pathway contributes to the anti-ageing benefits of physical exercise has not been established yet. METHODS: Swim exercise training and wheel running were used to measure lifespan in the nematode Caenorhabditis elegans and skeletal muscle quality in mice, respectively. Muscle weight, muscle fibre cross-sectional area (CSA) and myonuclei number were used to evaluate muscle mass. RNA sequencing (RNA-Seq) analysis of skeletal muscle in exercised mice was used to study the underlying mechanisms. Western blot and immunofluorescence were performed to explore autophagy- and senescence-related markers. RESULTS: The C. elegans adiponectin receptor PAQR-1/AdipoR1, but not PAQR-2/AdipoR2, was activated (3.55-fold and 3.48-fold increases in p-AMPK on Days 1 and 6, respectively, P < 0.001), which was involved in lifespan extension in exercised worms. Exercise training increased skeletal muscle mass index (1.29-fold, P < 0.01), muscle weight (1.75-fold, P < 0.001), myonuclei number (1.33-fold, P < 0.05), muscle fibre CSA (1.39-fold, P < 0.05) and capillary abundance (2.19-fold, P < 0.001 for capillary density; 1.58-fold, P < 0.01 for capillary number) in aged mice. Physical exercise reduced protein (2.94-fold, P < 0.001) and mRNA levels (1.70-fold, P < 0.001) of p16INK4a , a marker for cellular senescence, in skeletal muscle of aged mice. These beneficial effects of exercise on skeletal muscle of mice were dependent on AdipoR1. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis for differentially expressed genes in skeletal muscle between exercised mice with and without AdipoR1 knockdown by RNA-Seq analysis revealed that several KEGG pathways, such as 'AMPK signalling pathway' (P < 0.001), 'FOXO signalling pathway' (P < 0.001) and 'autophagy' (P < 0.001) were overrepresented. Knockdown of FoxO3a inhibited exercise-mediated beneficial effects on skeletal muscle quality of mice by inhibiting autophagy/mitophagy (3.81-fold reduction in LC3-II protein, P < 0.001; 1.53-fold reduction in BNIP3 protein, P < 0.05). Knockdown of daf-16, the FoxO homologue in C. elegans, reduced autophagy (2.77-fold and 2.06-fold reduction in GFP::LGG-1 puncta in seam cells and the intestine, respectively, P < 0.05) and blocked lifespan extension by exercise in worms. CONCLUSIONS: Our findings provide insights into how the AdipoR1 pathway has an impact on the anti-ageing benefits of exercise and implicate that activation of the AdipoR1 signalling may represent a potential therapeutic strategy for reducing age-related loss of skeletal muscle.

Protective Effects of Polydatin from Grapes and Reynoutria japonica Houtt. on Damaged Macrophages Treated with Acetaminophen.

The unregulated use of acetaminophen (APAP), an antipyretic and analgesic drug, harms hepatocytes and kidney cells, leading to liver failure and acute kidney injury. Herein, we investigate whether APAP damages macrophages in the immune system by observing its effects on macrophage proliferation and apoptosis. Using proteomics, we analyzed the effects of APAP on macrophage protein expression profiles and evaluated whether polydatin, the active ingredient in grapes and wine, can repair the damaged cells. The results showed that APAP alters the morphology and physiological processes of macrophages, inhibits macrophage proliferation, and promotes apoptosis. We observed 528 differentially expressed proteins when 500 µg/mL APAP was administered to the cells. These proteins are involved in biological processes including cell division, apoptosis, and acute phase response. Overall, our findings demonstrate that APAP harms the immune system by damaging macrophages and that polydatin can repair this damage.

Autophagy induced by H. pylori VacA regulated the survival mechanism of the SGC7901 human gastric cancer cell line.

BACKGROUND: Vacuolating cytotoxin (VacA) is an important virulence factor of Helicobacter pylori (H. pylori). It was previously believed that VacA can trigger the cascade of apoptosis on mitochondria to lead to cell apoptosis. Recently, it was found that VacA can induce autophagy. However, the molecular mechanism by which VacA induces autophagy is largely unknown. OBJECTIVE: We aimed to explore the molecular mechanism of autophagy induced by H. pylori in gastric cancer cells and the effect of autophagy on the survival of gastric cancer cells. METHODS: The autophagy of human gastric cancer cell line SGC7901 was detected by Western blot and RT-PCR in the treatment of VacA protein of H. pylori. The relationship between autophagy and reactive oxygen species (ROS) in the proliferation of gastric cancer cells were studied by gene expression silences (siRNA) and CM-H2DCFDA (DCF) staining. RESULTS: The results showed that VacA protein secreted by H. pylori in the supernatant stimulated autophagy in SGC7901 cells. After VacA protein treatment, the mRNA expressions of BECN1, ATG7 and PIK3C3, were up-regulated. ATG7 silencing by siRNA inhibited VacA-induced autophagy. Furthermore, our data demonstrated that VacA protein increased ROS levels. Addition of the antioxidant N-acetyl-L-cysteine (NAC) suppressed the levels of ROS, leading to inhibition of autophagy. CONCLUSIONS: H. pylori VacA is a key toxin that induces autophagy by increased ROS levels. And our findings demonstrated that VacA significantly inhibited proliferation in SGC7901 cells.

Association between homocysteine and obesity: A meta-analysis.

According to previous studies of obesity, we found that the association between homocysteine concentrations and obesity was reported controversially. Thus, we carried out this meta-analysis to investigate this association. We searched PubMed, The Cochrane library, and EMBASE database for studies that evaluate the relationship between homocysteine concentrations and obesity from inception to March, 2019. The quality of all included studies was assessed by the Newcastle Ottawa Scale (NOS) and the Agency for Healthcare Research Quality (AHRQ). The RevMan5.3 software and Stata12.0 software were used for conducting all data analyses. Standardized mean differences (SMD) with the corresponding 95% confidence intervals (95% CIs) were used as a measure of effect size to assess the relationship between homocysteine concentrations and obesity through a meta-analysis. The level of significance was set at P < .05. A total of 14 studies were ultimately included in our meta-analysis. Meta-analysis of the 14 studies found remarkable lower homocysteine concentrations in controls than in obese patients (SMD = 0.76, 95% CI = 0.25-1.27, P < .01; I2  = 94% and P < .01 for heterogeneity), regardless of nutritional status, dietary habit, insulin resistance (IR) status, special disease history, history of medicine taken, genetic background, and so on. Homocysteine concentrations in nonobese patients with polycystic ovarian syndrome (PCOS) were lower than obese patients with PCOS (SMD = 0.48, 95% CI = 0.20-0.77, P < .01; I2  = 39% and P = .18 for heterogeneity). The result of our meta-analysis showed that homocysteine concentrations were significantly elevated among obese patients.

YAP in epithelium senses gut barrier loss to deploy defenses against pathogens.

Pathogens commonly disrupt the intestinal epithelial barrier; however, how the epithelial immune system senses the loss of intestinal barrier as a danger signal to activate self-defense is unclear. Through an unbiased approach in the model nematode Caenorhabditis elegans, we found that the EGL-44/TEAD transcription factor and its transcriptional activator YAP-1/YAP (Yes-associated protein) were activated when the intestinal barrier was disrupted by infections with the pathogenic bacterium Pseudomonas aeruginosa PA14. Gene Ontology enrichment analysis of the genes containing the TEAD-binding sites revealed that "innate immune response" and "defense response to Gram-negative bacterium" were two top significantly overrepresented terms. Genetic inactivation of yap-1 and egl-44 significantly reduced the survival rate and promoted bacterial accumulation in worms after bacterial infections. Furthermore, we found that disturbance of the E-cadherin-based adherens junction triggered the nuclear translocation and activation of YAP-1/YAP in the gut of worms. Although YAP is a major downstream effector of the Hippo signaling, our study revealed that the activation of YAP-1/YAP was independent of the Hippo pathway during disruption of intestinal barrier. After screening 10 serine/threonine phosphatases, we identified that PP2A phosphatase was involved in the activation of YAP-1/YAP after intestinal barrier loss induced by bacterial infections. Additionally, our study demonstrated that the function of YAP was evolutionarily conserved in mice. Our study highlights how the intestinal epithelium recognizes the loss of the epithelial barrier as a danger signal to deploy defenses against pathogens, uncovering an immune surveillance program in the intestinal epithelium.

[Microbial synthesis of salidroside].

Salidroside, as one of the main active ingredients of Rhodiala plant, has the effects of anti-hypoxia, anti-radiation, anti-fatigue, anti-tumor, hypoglycemia and improving immunity. With the increasing demand for salidroside and the decreasing of plant resources, microbial production of salidroside has attracted much attention due to its advantages of short period and easy controlling. At present, microbial production of salidroside is still at the basic research stage. In order to make it easier for researchers to understand the advances of microbial synthesis of salidroside, the biosynthesis pathways, uridine diphosphate glucosyltransferases, wild strain/natural enzymes and engineered strain/recombinant enzymes were reviewed.

Antiproliferative Activity of Triterpene Glycoside Nutrient from Monk Fruit in Colorectal Cancer and Throat Cancer.

Colorectal cancer and throat cancer are the world's most prevalent neoplastic diseases, and a serious threat to human health. Plant triterpene glycosides have demonstrated antitumor activity. In this study, we investigated potential anticancer effects of mogroside IVe, a triterpenoid glycoside from monk fruit, using in vitro and in vivo models of colorectal and laryngeal cancer. The effects of mogroside IVe on the proliferation of colorectal cancer HT29 cells and throat cancer Hep-2 cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and the expression levels of p53, phosphorylated ERK1/2, and MMP-9 were analyzed by western blotting and immunohistochemistry. The results indicated that mogroside IVe inhibited, in a dose-dependent manner, the proliferation of HT29 and Hep-2 cells in culture and in xenografted mice, which was accompanied by the upregulation of tumor suppressor p53, and downregulation of matrix metallopeptidase 9 (MMP-9) and phosphorylated extracellular signal-regulated kinases (ERK)1/2. This study revealed the suppressive activity of mogroside IVe towards colorectal and throat cancers and identified the underlying mechanisms, suggesting that mogroside IVe may be potentially used as a biologically-active phytochemical supplement for treating colorectal and throat cancers.

Pseudomonas toxin pyocyanin triggers autophagy: Implications for pathoadaptive mutations.

Pseudomonas aeruginosa can establish life-long chronic infection in patients with cystic fibrosis by generating genetic loss-of-function mutations, which enhance fitness of the bacterium in the airways. However, the precise role of the pathoadaptive mutations in persistence in chronic airways infection remains largely unknown. Here we demonstrate that pyocyanin, a well-described P. aeruginosa virulence factor that plays an important role in the initial infection, promotes autophagy in bronchial epithelial cells. Disruption of phzM, which is required for pyocyanin biosynthesis, leads to a significant reduction in autophagy in Beas-2B cells and lung tissues. Pyocyanin-induced autophagy is mediated by the EIF2AK4/GCN2-EIF2S1/eIF2α-ATF4 pathway. Interestingly, rats infected with the phzMΔ mutant strain have high mortality rate and numbers of colony-forming units, compared to those infected with wild-type (WT) P. aeruginosa PA14 strain, during chronic P. aeruginosa infection. In addition, the phzMΔ mutant strain induces more extensive alveolar wall thickening than the WT strain in the pulmonary airways of rats. As autophagy plays an essential role in suppressing bacterial burden, our findings provide a detailed understanding of why reduction of pyocyanin production in P. aeruginosa in chronic airways infections has been associated with better host adaptation and worse outcomes in cystic fibrosis.

Recombinant human lactoferrin enhances the efficacy of triple therapy in mice infected with Helicobacter pylori.

Helicobacter pylori (H. pylori) is a life-threatening pathogen which causes chronic gastritis, gastric ulcers and even stomach cancer. Treatment normally involves bacterial eradication; however, this type of treatment only has a rate of effectiveness of <80%. Thus, it is a matter of some urgency to develop new therapeutic strategies. Lactoferrin, a member of the transferrin family of iron-binding proteins, has been proven to be effective in removing a vast range of pathogens, including H. pylori. In the present study, we examined the effectiveness of recombinant human lactoferrin (rhLf) isolated from transgenic goats as a treatment for H. pylori in vitro and in vivo. For the in vivo experiments, BALB/c mice received an intragastric administration of 0.1 ml of a suspension of H. pylori. The mice were then divided into 4 groups: group A, treated with saline; group B, treated with 1.5 g of rhLF; group C, treated with the standard triple therapy regimen; and group D, treated with the standard triple therapy regimen plus.5 g of rhLF. Following sacrifice, the stomach tissues of the mice were histologically examined for the presence of bacteria. For the in vitro experiments, the bacteria were cultured in BHI broth and RT-qPCR and western blot analysis were carried out to determine the mRNA and protein levels of virulence factors (CagA and VacA) in the cultures. Our results revealed that rhLf not only inhibited the growth of H. pylori, but also suppressed the expression of two major virulence factors. Moreover, rhLf markedly increased bacterial eradication and effectively reduced the inflammatory response when combined with the standard triple therapy regimen. These results provide evidence supporting the use of rhLF as an adjuvant to traditional therapeutic strategies in the treatment of H. pylori.

Mogrol represents a novel leukemia therapeutic, via ERK and STAT3 inhibition.

Unlike solid tumors, the primary strategy for leukemia treatment is chemotherapy. However, leukemia chemotherapy is associated with adverse drug effects and drug resistance. Therefore, it is imperative to identify novel agents that effectively treat leukemia while minimizing adverse effects. The Raf/MEK/extracellular regulated kinase (ERK) and signal transducer and activator of transcription 3 (STAT3) pathways have been implicated in leukemia carcinogenesis, and provide novel molecular targets for therapeutic intervention in cancer. Mogrol, a biometabolite of mogrosides found in Siraitia grosvenorii, has exhibited anti-cancer activities; however, the underlying mechanism of this effect remains unclear. To clarify its anti-cancer activity and mechanism of action, we treated K562 leukemia cells with mogrol. Mogrol suppressed leukemia cell growth via inhibition of the ERK1/2 and STAT3 pathways, in particular, through the suppression of p-ERK1/2 and p-STAT3. Inhibition of these pathways suppressed Bcl-2 expression, thereby inducing K562 cell apoptosis. Furthermore, mogrol enhanced p21 expression, resulting in G0/G1 cell cycle arrest. The findings provide new perspectives regarding the role of mogrol in leukemia treatment.

Risk factors for colorectal neoplasms based on colonoscopy and pathological diagnoses of Chinese citizens: a multicenter, case-control study.

PURPOSE: Since observational data in the urban residents are required to better assess the risk factors of colorectal neoplasm occurrence and the effectiveness of colonoscopy screening and surveillance, we conducted a case-control study at multicenters in China to identify patient characteristics and neoplasm features of colorectal adenoma (CRA) and colorectal carcinoma (CRC). METHODS: A total of 4089 patients who had undergone a colonoscopy from 19 hospitals were enrolled, of which 1106 had CRA and 466 had CRC. They were compared with controls. The analysis provides features and risk factors of colorectal neoplasm using multivariate logistic regression. RESULTS: Increasing age, a family history of colorectal cancer or previous cases of colorectal adenoma or hypertension disease, gastrointestinal surgery, regular intake of pickled food (adjusted odds ratio [aOR] 1.42, 95 % confidence interval [CI], 1.048-1.924), consumption of alcohol, and a positive result of fecal occult blood testing (FOBT; aOR 2.509, 95 % CI 1.485-4.237) were associated with an increased risk of CRA. In the CRC group, increasing age, regular intake of pickled foods, and a positive FOBT result were risk factors. In addition, a positive abdominal computed tomography (CT) before a colonoscopy and physical signs of emaciation were also significantly associated with an increasing risk of colorectal carcinoma. Regular intake of vegetables decreased the risk of both CRA and CRC. CONCLUSIONS: Age, pickled foods, and a positive FOBT are risk factors for colorectal neoplasm. Vegetable intake was associated with a decreased risk of CRA and CRC.

Homocysteine inhibits hepatocyte proliferation via endoplasmic reticulum stress.

Homocysteine is an independent risk factor for coronary, cerebral, and peripheral vascular diseases. Recent studies have shown that levels of homocysteine are elevated in patients with impaired hepatic function, but the precise role of homocysteine in the development of hepatic dysfunction is unclear. In this study, we examined the effect of homocysteine on hepatocyte proliferation in vitro. Our results demonstrated that homocysteine inhibited hepatocyte proliferation by up-regulating protein levels of p53 as well as mRNA and protein levels of p21(Cip1) in primary cultured hepatocytes. Homocysteine induced cell growth arrest in p53-positive hepatocarcinoma cell line HepG2, but not in p53-null hepatocarcinoma cell line Hep3B. A p53 inhibitor pifithrin-α inhibited the expression of p21(Cip1) and attenuated homocysteine-induced cell growth arrest. Homocysteine induced TRB3 expression via endoplasmic reticulum stress pathway, resulting in Akt dephosphorylation. Knock-down of endogenous TRB3 significantly suppressed the inhibitory effect of homocysteine on cell proliferation and the phosphorylation of Akt. LiCl reversed homocysteine-mediated cell growth arrest by inhibiting TRB3-mediated Akt dephosphorylation. These results demonstrate that both TRB3 and p21(Cip1) are critical molecules in the homocysteine signaling cascade and provide a mechanistic explanation for impairment of liver regeneration in hyperhomocysteinemia.

Hyperhomocysteinemia stimulates hepatic glucose output and PEPCK expression.

Homocysteine is an intermediate in the sulfur amino acid metabolism. Recent studies suggested that there might be links between hyperhomocysteinemia and insulin resistance. In the present study, we investigated the effect of homocysteine on glucose metabolism. We demonstrated that the levels of insulin were significantly higher in mice with hyperhomocysteinemia than those in the normal mice after administration of glucose. The effect of insulin on glucose output was significantly blocked in the homocysteine-treated hepatocytes. In addition, the expression of phosphoenolpyruvate carboxykinase (PEPCK) gene was elevated in the liver of mice with hyperhomocysteinemia and primary mouse hepatocytes treated with homocysteine. The action of homocysteine was suppressed by H89, a protein kinase A (PKA) inhibitor. Thus, hyperhomocysteinemia may be considered as a risk factor that contributes to the development of insulin resistance with respect to elevated glucose output and upregulation of PEPCK, probably via the PKA pathway. Our study provides a novel mechanistic explanation for the development of insulin resistance in hyperhomocysteinemia.

Isolation and characterization of AaWRKY1, an Artemisia annua transcription factor that regulates the amorpha-4,11-diene synthase gene, a key gene of artemisinin biosynthesis.

Amorpha-4,11-diene synthase (ADS) of Artemisia annua catalyzes the conversion of farnesyl diphosphate into amorpha-4,11-diene, the first committed step in the biosynthesis of the antimalarial drug artemisinin. The promoters of ADS contain two reverse-oriented TTGACC W-box cis-acting elements, which are the proposed binding sites of WRKY transcription factors. A full-length cDNA (AaWRKY1) was isolated from a cDNA library of the glandular secretory trichomes (GSTs) in which artemisinin is synthesized and sequestered. AaWRKY1 encodes a 311 amino acid protein containing a single WRKY domain. AaWRKY1 and ADS genes were highly expressed in GSTs and both were strongly induced by methyl jasmonate and chitosan. Transient expression analysis of the AaWRKY1-GFP (green fluorescent protein) reporter revealed that AaWRKY1 was targeted to nuclei. Biochemical analysis demonstrated that the AaWRKY1 protein was capable of binding to the W-box cis-acting elements of the ADS promoters, and it demonstrated transactivation activity in yeast. Co-expression of the effector construct 35S::AaWRKY1 with a reporter construct ADSpro1::GUS greatly activated expression of the GUS (beta-glucuronidase) gene in stably transformed tobacco. Furthermore, transient expression experiments in agroinfiltrated Nicotiana benthamiana and A. annua leaves showed that AaWRKY1 protein transactivated the ADSpro2 promoter activity by binding to the W-box of the promoter; disruption of the W-box abolished the activation. Transient expression of AaWRKY1 cDNA in A. annua leaves clearly activated the expression of the majority of artemisinin biosynthetic genes. These results strongly suggest the involvement of the AaWRKY1 transcription factor in the regulation of artemisinin biosynthesis, and indicate that ADS is a target gene of AaWRKY1 in A. annua.