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1.
Org Lett ; 26(20): 4200-4204, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38739265

ABSTRACT

Solvent-switchable and site-selective phosphorylation of imidazoles at the C2 or C5 position of the imidazole ring was achieved via 1,4-palladium migration. P-Chiral tert-butyl(aryl)phosphine oxides were cross-coupled to 1-(2-bromophenyl)-1H-imidazoles with high enantiospecificity, thereby leading to a novel class of chiral imidazole-based phosphine oxides. As proof of concept, reduction of an analogue yielded the corresponding P-chiral 2-phosphinyl imidazole ligand, which was shown to induce high enantioselectivity in the formation of axially chiral molecules synthesized via Pd-catalyzed Suzuki-Miyaura cross-coupling.

2.
Discov Oncol ; 15(1): 32, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38329652

ABSTRACT

BACKGROUND: Solitary fibrous tumors (SFT) and meningiomas (MA) have similar clinical and radiographic presentations but require different treatment approaches and have different prognoses. This emphasizes the importance of a correct preoperative diagnosis of SFT versus MA. OBJECTIVE: In this study, investigated the differences in imaging characteristics between SFT and MA to improve the accuracy of preoperative imaging diagnosis of SFT. METHODS: The clinical and imaging data of 26 patients with SFT and 104 patients with MA who were pathologically diagnosed between August 2017 and December 2022, were retrospectively analyzed. The clinical and imaging differences between SFT and MA, as well as between the various pathological grades of SFT, were analyzed. RESULTS: Age, gender, cystic change, flow void phenomenon, yin-yang sign, lobulation, narrow base, tumor/cortex signal ratio (TCSR) > 1.0 in T1-weighted imaging (T1WI), TCSR ≥ 1.1 in T2-weighted imaging (T2WI), peritumoral edema, and absence of dural tail sign varied between SFT and MA. As per the receiver operating characteristic (ROC) curve analysis, TCSR > 1 in T1WI has the maximum diagnostic accuracy for SFT. Cranial or venous sinus invasion had a positive effect on SFT (Grade III, World Health Organization (WHO) grading). CONCLUSION: Among the many radiological and clinical distinctions between SFT and MA, TCSR ≥ 1 exhibits the highest predictive efficacy for SFT; while cranial or venous sinus invasion may be a predictor of WHO grade III SFT.

3.
Pest Manag Sci ; 80(3): 1107-1117, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37862262

ABSTRACT

BACKGROUND: Chlorantraniliprole (CAP) is a diamide insecticide with high efficacy against many pest insects, including the black cutworm, Agrotis ipsilon. Agrotis ipsilon is a serious pest causing significant yield losses in crops. Glutathione-S-transferases (GSTs) belong to a family of metabolic enzymes that can detoxify a wide range of pesticides. However, little is known about the functions of GSTs in CAP tolerance in A. ipsilon. RESULTS: A cDNA sequence (designated AiGSTu1) encoding an unclassified GST was identified from A. ipsilon. AiGSTu1 is highly expressed during the 3rd -instar larval and the pupal stages. Most of the mRNA transcripts were found in larval Malpighian tubules. Exposure to CAP strongly enhanced AiGSTu1 expression, GST activity, hydrogen peroxide (H2 O2 ) and malondialdehyde levels in larvae. H2 O2 treatment upregulated the transcription level of AiGSTu1, suggesting that CAP-induced oxidative stress may activate AiGSTu1 expression. The activity of recombinant AiGSTu1 was inhibited by CAP in a dose-dependent manner. Metabolism assay results demonstrated that AiGSTu1 is capable of depleting CAP. Overexpression of AiGSTu1 enhanced the tolerance of Escherichia coli cells to H2 O2 and the oxidative stress inducer, cumene hydroperoxide. Silencing of AiGSTu1 by RNA interference increased the susceptibility of A. ipsilon larvae to CAP. CONCLUSION: The findings of this study provide valuable insights into the potential role of AiGSTu1 in CAP detoxification and will improve our understanding of CAP tolerance in A. ipsilon. © 2023 Society of Chemical Industry.


Subject(s)
Glutathione Transferase , Moths , ortho-Aminobenzoates , Animals , Moths/genetics , Larva , Glutathione
4.
J Agric Food Chem ; 71(51): 20680-20689, 2023 Dec 27.
Article in English | MEDLINE | ID: mdl-38088263

ABSTRACT

The black cutworm Agrotis ipsilon is a serious crop pest. Phoxim, an organophosphorus insecticide, has been widely used to control A. ipsilon. When phoxim is extensively applied, the susceptibility of A. ipsilon to insecticide is reduced. However, the mechanisms of tolerance of A. ipsilon to phoxim remain unclear. Herein, we report that an epsilon class glutathione S-transferase, AiGSTE1, confers phoxim tolerance in A. ipsilon. Exposure to a sublethal concentration (LC50) of phoxim caused oxidative stress and activated the transcription of AiGSTe1 genes in A. ipsilon larvae. Recombinant AiGSTE1 expressed in Escherichia coli could metabolize phoxim. Furthermore, E. coli cells overexpressing AiGSTE1 displayed significant tolerance to oxidative stress. Knockdown of AiGSTe1 by RNA interference significantly increased the mortality of A. ipsilon larvae to phoxim. These results demonstrate that AiGSTE1 confers phoxim tolerance in A. ipsilon by metabolizing the insecticide and preventing phoxim-induced oxidative stress.


Subject(s)
Insecticides , Lepidoptera , Moths , Animals , Insecticides/pharmacology , Escherichia coli/genetics , Organophosphorus Compounds , Moths/genetics , Larva/genetics
5.
Chin J Integr Med ; 2023 Aug 24.
Article in English | MEDLINE | ID: mdl-37612478

ABSTRACT

OBJECTIVE: To provide comprehensive evidence for the anti-cancer cachexia effect of Jianpi Decoction (JP) and to explore its mechanism of anti-cancer cachexia. METHODS: A mouse model of colon cancer (CT26)-induced cancer cachexia (CC) was used to investigate the anti-CC effect of JP combined with medroxyprogesterone acetate (MPA). Thirty-six mice were equally divided into 6 groups: normal control, CC, MPA (100 mg•kg-1•d-1), MPA + low-dose (20 mg•kg-1•d-1) JP (L-JP), MPA + medium-dose (30 mg•kg-1•d-1) JP (M-JP), and MPA + high-dose (40 mg•kg-1•d-1) JP (H-JP) groups. After successful modeling, the mice were administered by gavage for 11 d. The body weight and tumor volume were measured and recorded every 2 d starting on the 8th day after implantation. The liver, heart, spleen, lung, kidney, tumor and gastrocnemius muscle of mice were collected and weighed. The pathological changes of the tumor was observed, and the cross-sectional area of the gastrocnemius muscle was calculated. The protein expressions of STAT3 and E3 ubiquitinase in the gastrocnemius muscle were measured by Western blot. In addition, an in vitro C2C12 myotube formation model was established to investigate the role of JP in hindering dexamethasone-induced muscle atrophy. In vitro experiments were divided into control, model, and JP serum groups. After 2-d administration, microscopic photographs were taken and myotube diameters were calculated. Western blot was performed to measure the protein expressions of STAT3 and E3 ubiquitinase. RESULTS: JP combined with MPA restored tumor-induced weight loss (P<0.05, vs. CC) and muscle fiber size (P<0.01, vs. CC). Mechanistically, JP reduced the expression of atrophy-related proteins MuRF1 and MAFbx in tumor-induced muscle atrophy in vivo (P<0.05, vs. CC). In addition, JP reduced the expression of atrophy-related proteins MuRF1 and MAFbx and p-STAT3 phosphorylation (P<0.05 or P<0.01 vs. model group) in C2C12 myotubes treated with dexamethasone in vitro. CONCLUSIONS: Administration of JP combined with MPA restores tumor-induced cachexia conditions. In addition, the profound effect of JP combined with MPA on tumor-induced cachexia may be due to its inhibition of muscle proteolysis (E3 ubiquitinase system).

6.
J Int Med Res ; 51(1): 3000605221149879, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36694984

ABSTRACT

We herein report two cases involving children who died of influenza A (H3N2) virus infection-associated encephalopathy/encephalitis (IAE). Both children developed convulsions and impaired consciousness within a relatively short period and eventually died of brainstem failure. Patient 1 presented with high fever, vomiting, and diarrhea. Laboratory tests indicated persistently high lactate, alanine aminotransferase, and urea nitrogen concentrations in the blood as well as a high protein concentration in the cerebrospinal fluid. Patient 2 presented with persistent hyperthermia and progressive disturbance of consciousness, but the cerebrospinal fluid remained normal during the disease course. Both patients were actively given oseltamivir antiviral treatment after diagnosis of influenza virus infection. However, the disease progressed and invasive mechanical ventilation was performed. Both children's condition quickly progressed to IAE, and they eventually died. IAE is a rare complication of influenza virus infection with high mortality, and its pathogenesis remains unclear. The purpose of this report is to draw attention to the serious central nervous system complications of influenza infection and raise awareness of the fatal consequences of this disease among pediatricians.


Subject(s)
Brain Diseases , Encephalitis , Influenza, Human , Orthomyxoviridae Infections , Humans , Child , Influenza, Human/diagnosis , Influenza A Virus, H3N2 Subtype , Brain Diseases/complications , Brain Diseases/diagnosis , Oseltamivir/therapeutic use
7.
Arch Insect Biochem Physiol ; 111(4): e21964, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36050844

ABSTRACT

Chlorantraniliprole (CAP) is an insecticide widely used to control the small white butterfly (SWB), Pieris rapae. Exposure to CAP can cause oxidative injury in SWB; however, it is unclear if antioxidant enzymes are involved in the defense process. In this study, a thioredoxin peroxidase (PrTPX1) gene was identified from SWB by using a homology search method. The gene encoded a 195 amino-acid PrTPX1 protein. Sequence characteristics and phylogenetic analysis indicated that PrTPX1 was a typical "2-Cys" TPX, and the PrTPX1 gene consisted of four exons and three introns. Reverse transcription-quantitative polymerase chain reaction analysis indicated that the messenger RNA levels of PrTPX1 were highest in third-, fourth- and fifth-instar larval stages and in the larval midgut. Treatment with sublethal doses (LD20 and LD50 ) of CAP for 6, 12, 18, and 24 h resulted in increased H2 O2 concentration in SWB larvae, indicating insecticide-induced oxidative stress. The transcriptional levels of PrTPX1 were significantly enhanced in larvae exposed to CAP. Recombinant PrTPX1 protein was expressed in Escherichia coli. Enzymatic assay revealed that the protein displayed antioxidant activity and was able to protect against oxidative challenge. These results indicated that PrTPX1 plays an important role in oxidative stress responses and may contribute to the CAP tolerance in SWB.


Subject(s)
Butterflies , Insecticides , Animals , Butterflies/genetics , Insecticides/toxicity , Insecticides/metabolism , Peroxiredoxins/genetics , Insect Proteins/genetics , Insect Proteins/metabolism , Phylogeny , Larva/genetics , Oxidative Stress
8.
Pestic Biochem Physiol ; 181: 104995, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35082025

ABSTRACT

Lambda-cyhalothrin (LCT) is a pyrethroid insecticide widely used to control insect pests. Insect exposure to LCT may cause abnormal accumulation of reactive oxygen species (ROS) and result in oxidative damage. Heat shock proteins (HSPs) may help protect against oxidative stress. However, little is known about the role of HSPs in response to LCT in the green peach aphid, Myzus persicae. This insect is an important agricultural pest causing severe yield losses in crops. In this study, we characterized a cDNA sequence (MpHsp70) encoding a member of the HSP70 family in M. persicae. MpHsp70 encoded a 623 amino acid protein putatively localized in the cytosol. The highest expression level of MpHsp70 occurred in fourth-instar nymphs. Treatment of M. persicae with LCT resulted in oxidative stress and significantly increased H2O2 and malondialdehyde levels. This led to an elevated transcription level of MpHsp70. Injection of H2O2 into M. persicae also upregulated the MpHsp70 expression level, suggesting that MpHsp70 is responsive to ROS, particularly H2O2, induced by LCT. Recombinant MpHSP70 protein was expressed in Escherichia coli. E. coli cells overexpressing MpHSP70 exhibited significant tolerance to H2O2 and the ROS generators, cumene hydroperoxide and paraquat. This indicated that MpHSP70 protects against oxidative stress. Furthermore, knockdown of MpHsp70 by RNA interference resulted in increased susceptibility in apterous adults of M. persicae to LCT. These findings indicate that MpHsp70 plays an important role in defense against LCT-induced oxidative stress and insecticide susceptibility in M. persicae.


Subject(s)
Aphids , Pyrethrins , Animals , Aphids/genetics , Escherichia coli , Heat-Shock Proteins/genetics , Hydrogen Peroxide/toxicity , Nitriles , Oxidative Stress , Pyrethrins/toxicity
9.
J Insect Sci ; 22(1)2022 Jan 01.
Article in English | MEDLINE | ID: mdl-34958664

ABSTRACT

Plant essential oils, with high bioactivity and biodegradability, provide promising alternatives to synthetic pesticides for pest control. Trans-anethole is the major component of essential oil from star anise, Illicium verum Hook. The compound has a strong contact toxicity against the green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), which is a major insect pest of many vegetables and crops. However, little information is known about how M. persicae responds to trans-anethole at the molecular level. We conducted a comparative transcriptome analysis of M. persicae in response to a LD50 dose of trans-anethole. A total of 559 differentially expressed genes were detected in the treated individuals, with 318 genes up-regulated, and 241 genes down-regulated. Gene ontology (GO) analysis revealed that these genes were classified into different biological processes and pathways. We also found that genes encoding ATP-binding cassette (ABC) transporters, DnaJ, and cuticle proteins were dramatically up-regulated in response to trans-anethole. To study the function of these genes, we performed RNA interference (RNAi) analysis. Knockdown of an ABC transporter gene (ABCG4) and a DnaJ gene (DnaJC1) resulted in a significantly increased mortality rate in M. persicae following trans-anethole exposure, indicating the involvement of these two genes in the toxicity response to trans-anethole. The findings provide new insights into the mechanisms of M. persicae in coping with plant essential oils.


Subject(s)
Allylbenzene Derivatives , Anisoles , Aphids , Insect Proteins/genetics , Oils, Volatile , Allylbenzene Derivatives/pharmacology , Animals , Anisoles/pharmacology , Aphids/drug effects , Aphids/genetics , Gene Expression , Oils, Volatile/pharmacology
10.
Arch Insect Biochem Physiol ; 108(2): e21835, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34309077

ABSTRACT

The green peach aphid, Myzus persicae (Sulzer), is a serious agricultural pest with a worldwide distribution. Catalase (CAT), which is encoded by the catalase (Cat) gene, is an extremely important antioxidant enzyme that plays a pivotal role in protecting cells against the toxic effects of hydrogen peroxide. The Cat gene has not been characterized in M. persicae; therefore, this study describes the identification of the Cat (MpCat) gene from M. persicae. MpCat contains an open reading frame of 1515 bp and encodes a MpCAT protein consisting of 504 amino-acid residues. MpCAT possesses features typical of other insect catalases, including 7 conserved amino acids involved in binding heme and 15 involved in binding nicotinamide adenine dinucleotide phosphate. Phylogenetic analysis showed that MpCAT was closely related to orthologs from other aphid species. MpCat consisted of nine exons and eight introns, and the number and insertion sites of introns are consistent with those of Cat genes from Acyrthosiphon pisum (Harris) and Aphis gossypii Glover. The mRNA transcripts of MpCat were detected at all tested developmental stages, with the highest mRNA level in alate adults. The expression of MpCat was significantly upregulated when M. persicae was exposed to low and high temperatures, ultraviolet radiation, Beauveria bassiana, and permethrin. The transcription of MpCat and the activity of catalase were suppressed by RNA interference, and knockdown of MpCat significantly reduced the survival rate in M. persicae under heat stress. The results provide valuable information for further study on the physiological functions of MpCat.


Subject(s)
Aphids , Catalase , Animals , Antioxidants/metabolism , Aphids/genetics , Aphids/metabolism , Catalase/genetics , Catalase/metabolism , Gene Expression Profiling , Genes, Insect , Insect Proteins/genetics , Insect Proteins/metabolism , Phylogeny , RNA Interference
11.
Integr Cancer Ther ; 20: 15347354211012749, 2021.
Article in English | MEDLINE | ID: mdl-33957783

ABSTRACT

BACKGROUND: Cancer is the second leading cause of death before the age of 70. Improved cancer survival has put increasing demands on cancer care. Palliative care is the specialized multi-disciplinary care providing relief from the pain, symptoms, and stress of serious illness. The study aims to evaluate the adjunctive effect of acupuncture for advanced cancer patients in a collaborative model of palliative care. METHODS/DESIGN: This is a single-blinded, randomized, sham-controlled trial. One hundred twenty advanced cancer patients undergoing palliative care will be randomized in a ratio of 2:1:1 to manual acupuncture plus standard care group (ASC), sham acupuncture plus standard care group (SSC), and standard care group (SC). Patients in ASC and SSC will receive 9 sessions of acupuncture or sham acupuncture for 3 weeks, and will be followed up for 2 months. The primary measure is the change from baseline score of the Edmonton Symptom Assessment System at 3 weeks. The secondary measures include the Brief Fatigue Inventory, Hospital Anxiety and Depression Scale, Insomnia Severity Index, Numeric Rating Scale, and European Organization for Research and Treatment of Cancer Quality of Life 15 items Questionnaire for Palliative Care. DISCUSSION: The finding of this trial will provide high-quality evidence on the adjunctive effect of acupuncture to standard care on advanced cancer patients undergoing palliative care. TRIAL REGISTRATION: Clinicaltrials.gov, NCT04398875 (https://www.clinicaltrials.gov/ct2/show/NCT04398875), Registered on 21 May 2020.


Subject(s)
Acupuncture Therapy , Neoplasms , Humans , Neoplasms/therapy , Palliative Care , Quality of Life , Randomized Controlled Trials as Topic , Treatment Outcome
12.
Pestic Biochem Physiol ; 174: 104825, 2021 May.
Article in English | MEDLINE | ID: mdl-33838718

ABSTRACT

Insecticide exposure typically leads to abnormally high levels of reactive oxygen species (ROS) and oxidative damage in insects. Superoxide dismutases (SODs) are potent antioxidant enzymes for ROS scavenging that are essential to protect insects against insecticide-induced oxidative injury. The small white butterfly, Pieris rapae, is an economically important lepidopteran pest of cruciferous crops, and the anthranilic diamide insecticide chlorantraniliprole is widely used to control this organism. However, whether chlorantraniliprole causes oxidative stress, and whether SODs are involved in ROS scavenging, remains unclear in P. rapae. In this study, an intracellular copper/zinc SOD (designated PrSOD1) gene was identified and characterised in P. rapae. The gene consists of four exons and three introns, and the PrSOD1 protein encoded by the gene has typical highly conserved features of CuZnSODs, including two signature motifs and seven Cu/Zn-interacting residues. Transcription of PrSOD1 was highest in the larval fat body and at the fifth-instar larval stage. Recombinant PrSOD1 protein expressed in Escherichia coli displayed antioxidant activity and high thermal and pH stability, confirming that PrSOD1 encodes a functional enzyme. Exposure to three sublethal doses of chlorantraniliprole for 6, 12 or 24 h resulted in significantly increased malondialdehyde concentration in P. rapae larvae, indicating insecticide-induced oxidative stress. Furthermore, both PrSOD1 transcription levels and CuZnSOD activity were quickly (6 and 12 h, respectively) upregulated in larvae subjected to chlorantraniliprole, strongly suggesting that PrSOD1 plays an important role in protecting against oxidative damage and possibly chlorantraniliprole tolerance in P. rapae.


Subject(s)
Butterflies , Animals , Copper/toxicity , Oxidative Stress , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism , Zinc , ortho-Aminobenzoates
13.
Chin J Integr Med ; 27(12): 919-926, 2021 Dec.
Article in English | MEDLINE | ID: mdl-32572780

ABSTRACT

OBJECTIVE: To screen the key Chinese Herbal Medicines (KCHMs) against breast cancer by data mining, and analyze the potential mechanism of KCHMs using network pharmacology method. METHODS: Clinical prescriptions consisted of CHMs for treating breast cancer were screened, and then Traditional Chinese Medicine Inheritance Support System (TCMISS) was applied to obtain the KCHMs. Subsequently, active ingredients and corresponding target genes of KCHMs were searched by Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) database, and target genes of breast cancer were collected using OMIM and MalaCards. After that, the overlapping target genes of KCHMs and breast cancer were screened, and the protein-protein interaction (PPI) network was built. In addition, a network of "KCHMs-active ingredients-breast cancer-targets" was constructed by Cytoscape 3.7.1. Finally, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analysis were performed with Database for Annotation, Visualization and Integrated Discovery (DAVID) database to reveal the action mechanism of KCHMs. RESULTS: A total of 7 KCHMs were identified, whose active ingredients include quercetin, luteolin, nobiletin, kaempferol, isorhamnetin, naringenin, and be-ta-sitosterol, etc. Based on protein-protein interaction analysis, core targets were ESR1, MYC, CCND1, EGFR, CASP3, ERBB2, etc. Several KEGG pathways (e.g, PI3K-Akt, p53, ErbB, and HIF-1 signaling pathways) were found. CONCLUSION: Based on the combination of the data mining method and network pharmacology approach, the therapeutic effect of KCHMs on breast cancer may be realized by acting on target genes and signaling pathways related to the formation and progression of breast cancer.


Subject(s)
Breast Neoplasms , Drugs, Chinese Herbal , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Data Mining , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Female , Humans , Medicine, Chinese Traditional , Network Pharmacology , Phosphatidylinositol 3-Kinases
14.
J Insect Sci ; 20(5)2020 Aug 01.
Article in English | MEDLINE | ID: mdl-32889524

ABSTRACT

The small white butterfly, Pieris rapae (L.), is an important insect pest of Brassica crops. This species utilize olfactory cues to find their hosts and mates. However, the molecular mechanism underlying the olfactory perception in this species remains unclear. Here, we identified 14 odorant-binding proteins (OBP) genes-essential for insect olfaction-in P. rapae by exploring a previously published transcriptome dataset. Proteins encoded by all of these genes contain N-terminal signal peptides and six positionally conserved cysteine residues, which are characteristic of insect OBPs. These OBPs displayed high amino acid identity with their respective orthologs in other lepidopterans, and several conserved motifs were identified within these OBPs. Phylogenetic analysis showed that these OBPs were well segregated from each other and clustered into different branches. PrapOBP1 and PrapOBP2 were clustered into the 'general odorant-binding protein' clade, and PrapOBP3 and PrapOBP4 fall into the 'pheromone-binding protein' clade. The 14 OBP genes were located on seven genomic scaffolds. Of these, PrapOBP1, 2, 3, and 4 were located on scaffold332, whereas PrapOBP5, 6, 7, 8, and 9 were located on scaffold116. Ten of the 14 genes had antenna-biased expression. Of these, PrapOBP1, 2, 4, and 13 were enriched in male antennae, whereas PrapOBP7 and PrapOBP10 were female-biased. Our findings suggest that these OBPs may be involved in olfactory communication. To the best of our knowledge, this is the first report on the identification and characterization of OBPs in P. rapae, and our findings provide a solid foundation for studying the functions of these genes.


Subject(s)
Butterflies/genetics , Insect Proteins/genetics , Receptors, Odorant/genetics , Transcriptome , Amino Acid Sequence , Animals , Butterflies/metabolism , Female , Gene Expression Profiling , Insect Proteins/chemistry , Insect Proteins/metabolism , Male , Phylogeny , Receptors, Odorant/chemistry , Receptors, Odorant/metabolism , Sequence Alignment
15.
J Med Chem ; 62(21): 9691-9702, 2019 11 14.
Article in English | MEDLINE | ID: mdl-31577901

ABSTRACT

Thienopyrimidine-based allosteric inhibitors of the human farnesyl pyrophosphate synthase (hFPPS), characterized by a chiral α-aminophosphonic acid moiety, were synthesized as enantiomerically enriched pairs, and their binding mode was investigated by X-ray crystallography. A general consensus in the binding orientation of all (R)- and (S)-enantiomers was revealed. This finding is a prerequisite for establishing a reliable structure-activity relationship (SAR) model.


Subject(s)
Aminoethylphosphonic Acid/chemistry , Aminoethylphosphonic Acid/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Ligases/antagonists & inhibitors , Ligases/chemistry , Polyisoprenyl Phosphates/metabolism , Sesquiterpenes/metabolism , Allosteric Regulation/drug effects , Humans , Ligases/metabolism , Models, Molecular , Protein Conformation , Stereoisomerism , Structure-Activity Relationship
16.
J Org Chem ; 84(11): 7291-7302, 2019 06 07.
Article in English | MEDLINE | ID: mdl-31099249

ABSTRACT

An asymmetric synthesis, amenable to library preparation of structurally diverse P-chiral t-butyl substituted secondary phosphine oxides (SPOs) and tertiary phosphine oxides (TPOs), was developed. A P-chiral H-phosphinate building block was prepared via a two-step, one-pot condensation of a chiral auxiliary with t-BuPCl2, followed by hydrolysis. Nucleophilic displacement of the chiral auxiliary with Grignard reagents, followed by hydrolysis, provided a library of P-chiral SPOs. In situ treatment of the prehydrolysis intermediate with electrophiles also provided a library of P-chiral TPOs in high enantiomeric purity.

17.
Arch Insect Biochem Physiol ; 99(1): e21476, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29873106

ABSTRACT

In insects, thioredoxin peroxidase (TPX) plays an important role in protecting against oxidative damage. However, studies on the molecular characteristics of TPXs in the Asiatic rice borer, Chilo suppressalis, are limited. In this work, a cDNA sequence (CsTpx3) encoding a TPX was identified from C. suppressalis. The deduced CsTPX3 protein shares high sequence identity and two positionally conserved cysteines with orthologs from other insect species, and was classified as a typical 2-Cys TPX. CsTpx3 was expressed most highly during the fifth-instar larval stage, and transcripts were most abundant in the midgut. Recombinant CsTPX3 protein expressed in Escherichia coli displayed the expected peroxidase activity by removing H2 O2 . Furthermore, CsTPX3 protected DNA from oxidative damage, and E. coli cells overexpressing CsTPX3 exhibited long-term resistance to oxidative stress. Exposure to various oxidative stressors, such as cold (8°C), heat (35°C), bacteria (E. coli), and two insecticides (chlorpyrifos and lambda-cyhalothrin), significantly upregulated transcription of CsTpx3. However, exposure to abamectin had no such effect. Our results provide valuable information for future studies on the antioxidant mechanism in this insect species.


Subject(s)
Gene Expression Regulation/physiology , Insect Proteins/genetics , Moths/genetics , Oxidative Stress/genetics , Peroxiredoxins/genetics , Amino Acid Sequence , Animals , Base Sequence , Female , Insect Proteins/chemistry , Insect Proteins/metabolism , Larva/enzymology , Larva/genetics , Larva/growth & development , Male , Moths/enzymology , Moths/growth & development , Peroxiredoxins/chemistry , Peroxiredoxins/metabolism , Phylogeny , Pupa/enzymology , Pupa/genetics , Pupa/growth & development , Sequence Alignment
18.
Arch Insect Biochem Physiol ; 98(1): e21455, 2018 May.
Article in English | MEDLINE | ID: mdl-29532954

ABSTRACT

The small white butterfly, Pieris rapae (Lepidoptera: Pieridae), is an important pest on Brassicaceae plants, causing heavy crop loss each year. Cytochrome P450 monooxygenase (CYP) is a superfamily of enzymes involved in the detoxification of various xenobiotic compounds, including insecticides. However, little is known about the role of CYP genes in P. rapae. In this study, we identified 63 CYP genes in P. rapae, and analyzed their phylogenetic relationships, exon-intron structures and genomic locations. Moreover, our insecticide-response transcription profiling showed that LD5 doses of lambda-cyhalothrin, chlorantraniliprole, and abamectin significantly increased expression of five (CYP4M59, CYP6AE119, CYP6AE120, CYP6AE121, and CYP6BD18), three (CYP4AU1, CYP6AE120, and CYP6AW1), and five (CYP4L40, CYP4AU1, CYP6AE119, CYP6AW1, and CYP6BD19) CYP genes, respectively; and LD20 doses of the three pesticides significantly upregulated six (CYP4M59, CYP6AE119, CYP6AE120, CYP6AE121, CYP4AU1, and CYP6BD18), six (CYP4G168, CYP4L40, CYP4AU1, CYP6AE120, CYP6AW1, and CYP6BD19), and five (CYP4L40, CYP4AU1, CYP6AB108, CYP6AE119, and CYP6BD19) genes, respectively. When we used LD50 doses of the three insecticides, we reported significantly elevated expression levels of five (CYP4M59, CYP6AE119, CYP6AE120, CYP6BD17, and CYP6BD18), eight (CYP4G168, CYP4L40, CYP4AU1, CYP6AE120, CYP6AE121, CYP6AW1, CYP6BD18, and CYP6BD19), and six (CYP4L40, CYP4S34, CYP6AB108, CYP6AE119, CYP6AE120, and CYP6BD19) genes, respectively. Our expression analysis also revealed that five (CYP4G168, CYP4G169, CYP4S34, CYP6AW1, and CYP6CT3) and three (CYP4L40, CYP6AN33, and CYP6BD17) CYP genes were mainly expressed in the midgut and fat body, respectively, and one CYP gene (CYP6AE119) in the Malpighian tubules. This is the first large-scale report into the characterization of CYP genes in P. rapae.


Subject(s)
Butterflies/enzymology , Cytochrome P-450 Enzyme System/genetics , Insect Proteins/genetics , Insecticides/pharmacology , Animals , Butterflies/drug effects , Cytochrome P-450 Enzyme System/metabolism , Female , Gene Expression , Insect Proteins/metabolism , Larva/drug effects , Larva/enzymology , Lethal Dose 50 , Male , Phylogeny
19.
Pestic Biochem Physiol ; 143: 102-110, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29183577

ABSTRACT

Insect glutathione S-transferases (GSTs) play essential roles in the detoxification of insecticides and other xenobiotic compounds. The cabbage white butterfly, Pieris rapae, is an economically important agricultural pest. In this study, 17 cDNA sequences encoding putative GSTs were identified in P. rapae. All cDNAs include a complete open reading frame and were designated PrGSTd1-PrGSTz2. Based on phylogenetic analysis, PrGSTs were divided into six classes (delta, epsilon, omega, sigma, theta and zeta). The exon-intron organizations of these PrGSTs were also analysed. Recombinant proteins of eight PrGSTs (PrGSTD1, PrGSTD2, PrGSTE1, PrGSTE2, PrGSTO1, PrGSTS1, PrGSTT1 and PrGSTZ1) were heterologously expressed in Escherichia coli, and all of these proteins displayed glutathione-conjugating activity towards 1-chloro-2,4-dinitrobenzene (CDNB). Expression patterns in various larval tissues, at different life stages, and following exposure to sublethal doses of abamectin, chlorantraniliprole or lambda-cyhalothrin were determined by reverse transcription-quantitative PCR. The results showed that PrGSTe3, PrGSTs1, PrGSTs2, and PrGSTs4 were mainly transcribed in the fat body, while PrGSTe2 was expressed predominantly in the Malpighian tubules. Four genes (PrGSTe2, PrGSTo4, PrGSTs4 and PrGSTt1) were mainly expressed in fourth-instar larvae, while others were ubiquitously expressed in egg, larval, pupa and/or adult stages. Abamectin treatment significantly upregulated ten genes (PrGSTd1, PrGSTd3, PrGSTe1, PrGSTe2, PrGSTo1, PrGSTo3, PrGSTs1, PrGSTs3, PrGSTs4 and PrGSTt1). Chlorantraniliprole and lambda-cyhalothrin treatment significantly upregulated nine genes (PrGSTd1, PrGSTd2, PrGSTe1, PrGSTe2, PrGSTe3, PrGSTs1, PrGSTs3, PrGSTs4 and PrGSTz1) and ten genes (PrGSTd1, PrGSTd3, PrGSTe1, PrGSTe2, PrGSTo1, PrGSTo2, PrGSTs1, PrGSTs2, PrGSTs3 and PrGSTz2), respectively. These GSTs are potentially involved in the detoxification of insecticides.


Subject(s)
Butterflies/genetics , Glutathione Transferase/genetics , Insect Proteins/genetics , Animals , Butterflies/drug effects , Female , Gene Expression Regulation, Developmental/drug effects , Insecticides/toxicity , Ivermectin/analogs & derivatives , Ivermectin/toxicity , Male , Nitriles/toxicity , Phylogeny , Pyrethrins/toxicity , ortho-Aminobenzoates/toxicity
20.
Org Lett ; 19(4): 894-897, 2017 02 17.
Article in English | MEDLINE | ID: mdl-28155279

ABSTRACT

A metal-free tandem reaction, initiated by the generation of a diazonium cation and followed by cycloetherification, was developed. Acid-promoted de-tert-butylation of N-nitroso N-tert-butylamine was used to generate a diazonium cation in situ, demonstrating a new application of nitroso chemistry. This reaction was employed in the synthesis of substituted benzofuran-3(2H)-ones and dihydrobenzo[d][1,3]oxaphosphole 3-oxides.

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