Title: Identification of the Flavone-Inducible Counter-Defense Genes and Their cis-Elements in Helicoverpa armigera Deng Z, Zhang Y, Fang L, Zhang M, Wang L, Ni X, Li X Ref: Toxins (Basel), 15:, 2023 : PubMed
Flavone is widely found in plants and plays an important role in plant defense against pests. Many pests, such as Helicoverpa armigera, use flavone as a cue to upregulate counter-defense genes for detoxification of flavone. Yet the spectrum of the flavone-inducible genes and their linked cis-regulatory elements remains unclear. In this study, 48 differentially expressed genes (DEGs) were found by RNA-seq. These DEGs were mainly concentrated in the retinol metabolism and drug metabolism-cytochrome P450 pathways. Further in silico analysis of the promoter regions of 24 upregulated genes predicted two motifs through MEME and five previously characterized cis-elements including CRE, TRE, EcRE, XRE-AhR and ARE. Functional analysis of the two predicted motifs and two different versions of ARE (named ARE1 and ARE2) in the promoter region of the flavone-inducible carboxylesterase gene CCE001j verified that the two motifs and ARE2 are not responsible for flavone induction of H. armigera counter-defense genes, whereas ARE1 is a new xenobiotic response element to flavone (XRE-Fla) and plays a decisive role in flavone induction of CCE001j. This study is of great significance for further understanding the antagonistic interaction between plants and herbivorous insects.
The metabolic syndrome (MetS) is a constellation of cardiovascular and metabolic symptoms involving insulin resistance, steatohepatitis, obesity, hypertension, and heart disease, and patients suffering from MetS often require polypharmaceutical treatment. PPARgamma agonists are highly effective oral antidiabetics with great potential in MetS, which promote adipocyte browning and insulin sensitization. However, the application of PPARgamma agonists in clinics is restricted by potential cardiovascular adverse events. We have previously demonstrated that the racemic dual sEH/PPARgamma modulator RB394 (3) simultaneously improves all risk factors of MetS in vivo. In this study, we identify and characterize the eutomer of 3. We provide structural rationale for molecular recognition of the eutomer. Furthermore, we could show that the dual sEH/PPARgamma modulator is able to promote adipocyte browning and simultaneously exhibits cardioprotective activity which underlines its exciting potential in treatment of MetS.
Title: Degradation of epigallocatechin and epicatechin gallates by a novel tannase Tan(Hcw) from Herbaspirillum camelliae Lei J, Zhang Y, Ni X, Yu X, Wang X Ref: Microb Cell Fact, 20:197, 2021 : PubMed
BACKGROUND: Herbaspirillum camelliae is a gram-negative endophyte isolated from the tea plant. Both strains WT00C and WT00F were found to hydrolyze epigallocatechin-3-gallate (EGCG) and epicatechin-3-gallate (ECG) to release gallic acid (GA) and display tannase activity. However, no tannase gene was annotated in the genome of H. camelliae WT00C. RESULTS: The 39 kDa protein, annotated as the prolyl oligopeptidase in the NCBI database, was finally identified as a novel tannase. Its gene was cloned, and the enzyme was expressed in E. coli and purified to homogeneity. Moreover, enzymatic characterizations of this novel tannase named Tan(Hcw) were studied. Tan(Hcw) was a secretary enzyme with a Sec/SPI signal peptide of 48 amino acids at the N-terminus, and it catalyzed the degradation of tannin, methyl gallate (MG), epigallocatechin-3-gallate (EGCG) and epicatechin-3-gallate (ECG). The optimal temperature and pH of Tan(Hcw) activities were 30 degreesC, pH 6.0 for MG and 40 degreesC, pH 7.0 for both EGCG and ECG. Na(+), K(+) Mn(2+) and Triton-X100, Tween80 increased the enzyme activity of Tan(Hcw), whereas Zn(2+), Mg(2+), Hg(2+), EMSO, EDTA and beta-mercaptoethanol inhibited enzyme activity. K(m), k(cat) and k(cat) /K(m) of Tan(Hcw) were 0.30 mM, 37.84 s(-1), 130.67 mM(-1) s(-1) for EGCG, 0.33 mM, 34.59 s(-1), 105.01 mM(-1) s(-1) for ECG and 0.82 mM, 14.64 s(-1), 18.17 mM(-1) s(-1) for MG, respectively. CONCLUSION: A novel tannase Tan(Hcw) from H. camelliae has been identified and characterized. The biological properties of Tan(Hcw) suggest that it plays a crucial role in the specific colonization of H. camelliae in tea plants. Discovery of the tannase Tan(Hcw) in this study gives us a reasonable explanation for the host specificity of H. camelliae. In addition, studying the characteristics of this enzyme offers the possibility of further defining its potential in industrial application.
Polypharmaceutical regimens often impair treatment of patients with metabolic syndrome (MetS), a complex disease cluster, including obesity, hypertension, heart disease, and type II diabetes. Simultaneous targeting of soluble epoxide hydrolase (sEH) and peroxisome proliferator-activated receptor gamma (PPARgamma) synergistically counteracted MetS in various in vivo models, and dual sEH inhibitors/PPARgamma agonists hold great potential to reduce the problems associated with polypharmacy in the context of MetS. However, full activation of PPARgamma leads to fluid retention associated with edema and weight gain, while partial PPARgamma agonists do not have these drawbacks. In this study, we designed a dual partial PPARgamma agonist/sEH inhibitor using a structure-guided approach. Exhaustive structure-activity relationship studies lead to the successful optimization of the designed lead. Crystal structures of one representative compound with both targets revealed potential points for optimization. The optimized compounds exhibited favorable metabolic stability, toxicity, selectivity, and desirable activity in adipocytes and macrophages.
INTRODUCTION: A significant number of mania patients fail to respond to current pharmacotherapy, thereby there is need for novel augmentation strategies. The results of some early studies showed the effectiveness of cholinomimetics in the treatment of mania. One open case series suggested the efficacy of donepezil in the treatment of bipolar disorder. Our aim was to explore whether an oral cholinesterase inhibitor, donepezil, administered during a 4-week treatment period, would benefit patients with acute mania. METHODS: We conducted a 4-week double-blind, placebo-controlled trial of donepezil as an adjunctive treatment to lithium in patients with acute mania. Eligible subjects were randomly assigned to receive donepezil or placebo in addition to lithium. Donepezil was started at 5 mg/day, and increased to 10 mg/day in the first week. Patients were rated with the Young Mania Rating Scale (YMRS) and Brief Psychiatric Rating Scale (BPRS) at baseline, day 1, week 1, week 2, and week 4. RESULTS: Out of the 30 patients who were enrolled, 15 were on donepezil and 15 were on placebo. All patients completed the 4-week trial. On the first day, there was a difference of 1.97 units on the psychomotor symptoms scale of the YMRS in the donepezil group as compared to the placebo group (t = 2.39, P = 0.02). There was a difference of 0.57 units (t = 2.09, P = 0.04) in the speech item and a difference of 0.29 units in the sexual interest item (t = 2.11, P = 0.04) in the donepezil group as compared to the placebo group. The total YMRS difference on the first day approached the conventional significance level (1.97 units, t = 1.84, P = 0.07). Over the course of 4 weeks, we failed to find that donepezil produced any significant difference in the YMRS (6.71 units difference, t = -1.44, P = 0.16) or the BPRS scale (1.29 units difference, t = -0.33, P = 0.75) as compared to placebo. Ten subjects (66.67%) in both groups met the criteria for clinical response (Fisher's exact P = 1.00). Five subjects (33.33%) in the donepezil group met the criteria for clinical remission while nine subjects (60.00%) in the placebo group met the remission criteria (Fisher's exact P = 0.27). CONCLUSION: Use of the oral anticholinergic donepezil had some benefit in the augmentation of lithium treatment on the first day, but did not provide any significant benefits in the long-term.
Title: Enzymatic chlorophyll degradation in wheat near-isogenic lines elicited by cereal aphid (Homoptera: Aphididae) feeding Wang T, Quisenberry SS, Ni X, Tolmay V Ref: J Econ Entomol, 97:661, 2004 : PubMed
Chlorophyll degradation enzyme (i.e., chlorophyllase, Mg-dechelatase, and chlorophyll oxidase) activities of aphid-infested and uninfested 'Tugela' and Tugela near-isogenic wheat lines (i.e., Tugela-Dn1, Tugela-Dn2, and Tugela-Dn5) were assayed. Chlorophyllase activity was higher in bird cherry-oat aphid, Rhopalosiphum padi (L.) (Homoptera: Aphididae),-infested wheat lines compared with Russian wheat aphid, Diuraphis noxia (Mordvilko) (Homoptera: Aphididae)]-infested and uninfested plants. Mg-dechelatase activity was higher in D. noxia-infested wheat lines than in R. padi-infested and uninfested plants. Also, Mg-dechelatase activity was lower in Tugela wheat infested with D. noxia than in Tugela near-isogenic lines with Dn genes. Based on the in vitro assays of chlorophyll degradation enzyme (i.e., chlorophyllase and Mg-dechelatase) activities, we proposed that the chlorotic symptoms observed on D. noxia-infested Tugela wheat were most likely to be elicited by unbalanced chlorophyll biosynthesis and degradation.
