RESUMO
OBJECTIVE: To describe the development of an innovative pre-pharmacy underrepresented mentorship program (PUMP) to provide guidance and support to pre-pharmacy students who are committed to serving underrepresented communities with health disparities. METHODS: Three virtual PUMP workshops were designed and delivered per admissions cycle for pre-pharmacy students who were applying to any school of pharmacy and self-identified as interested in serving underrepresented communities. Faculty, current pharmacy students, staff, and school leadership provided guidance and support on the application and interview process and how to select a program once offered admission. Data collection included the number of students who attended each workshop, were accepted to, and matriculated to the school of pharmacy. Pre- and post-workshop surveys provided insight into communities that attendees were committed to serving, perceptions of the workshops, and intent to matriculate, if accepted. RESULTS: During the first three admissions cycles, 189 pre-pharmacy students participated in eight PUMP workshops. A favorable trend was observed with an increased number of participants annually and an increased number of attendees who matriculated (an average of 34% over three cycles). Attendees were committed to addressing health disparities in various communities including, but not limited to, Southeast Asian, Latinx, Native American, LGBTQIA, Black/African American, Refugee, and Pacific Islanders. Most attendees (96%) reported that attending PUMP workshop(s) positively changed their impression of the school. CONCLUSION: A pilot pre-pharmacy mentorship program was developed and implemented. A growth in program participation and matriculation of students over three cycles who self-identified as committed to serving underrepresented communities was observed.
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Dietary lipids play an essential role in regulating the function of the gut microbiota and gastrointestinal tract, and these luminal interactions contribute to mediating host metabolism. Palmitic Acid Hydroxy Stearic Acids (PAHSAs) are a family of lipids with antidiabetic and anti-inflammatory properties, but whether the gut microbiota contributes to their beneficial effects on host metabolism is unknown. Here, we report that treating chow-fed female and male germ-free (GF) mice with PAHSAs improves glucose tolerance, but these effects are lost upon high fat diet (HFD) feeding. However, transfer of feces from PAHSA-treated, but not vehicle-treated, chow-fed conventional mice increases insulin sensitivity in HFD-fed GF mice. Thus, the gut microbiota is necessary for, and can transmit, the insulin-sensitizing effects of PAHSAs in HFD-fed GF male mice. Analyses of the cecal metagenome and lipidome of PAHSA-treated mice identified multiple lipid species that associate with the gut commensal Bacteroides thetaiotaomicron (Bt) and with insulin sensitivity resulting from PAHSA treatment. Supplementing live, and to some degree, heat-killed Bt to HFD-fed female mice prevented weight gain, reduced adiposity, improved glucose tolerance, fortified the colonic mucus barrier and reduced systemic inflammation compared to HFD-fed controls. These effects were not observed in HFD-fed male mice. Furthermore, ovariectomy partially reversed the beneficial Bt effects on host metabolism, indicating a role for sex hormones in mediating the Bt probiotic effects. Altogether, these studies highlight the fact that PAHSAs can modulate the gut microbiota and that the microbiota is necessary for the beneficial metabolic effects of PAHSAs in HFD-fed mice.
Assuntos
Dieta Hiperlipídica , Microbioma Gastrointestinal , Resistência à Insulina , Obesidade , Animais , Masculino , Feminino , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Obesidade/metabolismo , Obesidade/microbiologia , Obesidade/etiologia , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL , Ácidos Esteáricos/metabolismo , Ácido Palmítico/metabolismo , Fezes/microbiologia , Camundongos ObesosRESUMO
Working in tandem with kinases via a dynamic interplay of phosphorylation and dephosphorylation of proteins, phosphatases regulate many cellular processes and thus represent compelling therapeutic targets. Here we leverage ultraviolet photodissociation to shed light on the binding characteristics of two covalent phosphatase inhibitors, T65 and rabeprazole, and their respective interactions with the human small C-terminal domain phosphatase 1 (SCP1) and its single-point mutant C181A, in which a nonreactive alanine replaces one key reactive cysteine. Top-down MS/MS analysis is used to localize the binding of T65 and rabeprazole on the two proteins and estimate the relative reactivities of each cysteine residue.
Assuntos
Espectrometria de Massas em Tandem , Raios Ultravioleta , Humanos , Espectrometria de Massas em Tandem/métodos , Cisteína/química , Cisteína/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Ligação Proteica , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosfoproteínas Fosfatases/química , Fosfoproteínas Fosfatases/metabolismo , Modelos MolecularesRESUMO
BACKGROUND: Glioblastoma (GBM) is an aggressive brain cancer associated with poor prognosis, intrinsic heterogeneity, plasticity, and therapy resistance. In some GBMs, cell proliferation is fueled by a transcriptional regulator, repressor element-1 silencing transcription factor (REST). RESULTS: Using CRISPR/Cas9, we identified GBM cell lines dependent on REST activity. We developed new small molecule inhibitory compounds targeting small C-terminal domain phosphatase 1 (SCP1) to reduce REST protein level and transcriptional activity in glioblastoma cells. Top leads of the series like GR-28 exhibit potent cytotoxicity, reduce REST protein level, and suppress its transcriptional activity. Upon the loss of REST protein, GBM cells can potentially compensate by rewiring fatty acid metabolism, enabling continued proliferation. Combining REST inhibition with the blockade of this compensatory adaptation using long-chain acyl-CoA synthetase inhibitor Triacsin C demonstrated substantial synergetic potential without inducing hepatotoxicity. CONCLUSIONS: Our results highlight the efficacy and selectivity of targeting REST alone or in combination as a therapeutic strategy to combat high-REST GBM.
Assuntos
Glioblastoma , Fatores de Transcrição , Humanos , Glioblastoma/tratamento farmacológico , Regulação da Expressão Gênica , Encéfalo , AgressãoRESUMO
The repertoire of modifications to bile acids and related steroidal lipids by host and microbial metabolism remains incompletely characterized. To address this knowledge gap, we created a reusable resource of tandem mass spectrometry (MS/MS) spectra by filtering 1.2 billion publicly available MS/MS spectra for bile-acid-selective ion patterns. Thousands of modifications are distributed throughout animal and human bodies as well as microbial cultures. We employed this MS/MS library to identify polyamine bile amidates, prevalent in carnivores. They are present in humans, and their levels alter with a diet change from a Mediterranean to a typical American diet. This work highlights the existence of many more bile acid modifications than previously recognized and the value of leveraging public large-scale untargeted metabolomics data to discover metabolites. The availability of a modification-centric bile acid MS/MS library will inform future studies investigating bile acid roles in health and disease.
Assuntos
Ácidos e Sais Biliares , Microbioma Gastrointestinal , Metabolômica , Espectrometria de Massas em Tandem , Animais , Humanos , Ácidos e Sais Biliares/química , Metabolômica/métodos , Poliaminas , Espectrometria de Massas em Tandem/métodos , Bases de Dados de Compostos QuímicosRESUMO
Determining the structure and phenotypic context of molecules detected in untargeted metabolomics experiments remains challenging. Here we present reverse metabolomics as a discovery strategy, whereby tandem mass spectrometry spectra acquired from newly synthesized compounds are searched for in public metabolomics datasets to uncover phenotypic associations. To demonstrate the concept, we broadly synthesized and explored multiple classes of metabolites in humans, including N-acyl amides, fatty acid esters of hydroxy fatty acids, bile acid esters and conjugated bile acids. Using repository-scale analysis1,2, we discovered that some conjugated bile acids are associated with inflammatory bowel disease (IBD). Validation using four distinct human IBD cohorts showed that cholic acids conjugated to Glu, Ile/Leu, Phe, Thr, Trp or Tyr are increased in Crohn's disease. Several of these compounds and related structures affected pathways associated with IBD, such as interferon-γ production in CD4+ T cells3 and agonism of the pregnane X receptor4. Culture of bacteria belonging to the Bifidobacterium, Clostridium and Enterococcus genera produced these bile amidates. Because searching repositories with tandem mass spectrometry spectra has only recently become possible, this reverse metabolomics approach can now be used as a general strategy to discover other molecules from human and animal ecosystems.
Assuntos
Amidas , Ácidos e Sais Biliares , Ésteres , Ácidos Graxos , Metabolômica , Animais , Humanos , Bifidobacterium/metabolismo , Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Clostridium/metabolismo , Estudos de Coortes , Doença de Crohn/metabolismo , Enterococcus/metabolismo , Ésteres/química , Ésteres/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Metabolômica/métodos , Fenótipo , Receptor de Pregnano X/metabolismo , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Amidas/química , Amidas/metabolismoRESUMO
Dietary lipids play an essential role in regulating the function of the gut microbiota and gastrointestinal tract, and these luminal interactions contribute to mediating host metabolism. PAHSAs are a class of lipids with anti-diabetic and anti-inflammatory properties, but whether the gut microbiota contributes to their beneficial effects on host metabolism is unknown. Here, we report that treating high fat diet (HFD)-fed germ-free mice with PAHSAs does not improve insulin sensitivity. However, transfer of feces from PAHSA-treated, but not Vehicle-treated, chow-fed mice increases insulin-sensitivity in HFD-fed germ free mice. Thus, the gut microbiota is necessary for and can transmit the insulin-sensitizing effects of PAHSAs in HFD-fed germ-free mice. Functional analyses of the cecal metagenome and lipidome of PAHSA-treated mice identified multiple lipid species that associate with the gut commensal Bacteroides thetaiotaomicron ( Bt ) and with insulin sensitivity resulting from PAHSA treatment. Bt supplementation in HFD-fed female mice prevented weight gain, reduced adiposity, improved glucose tolerance, fortified the colonic mucus barrier and reduced systemic inflammation versus chow-fed controls, effects that were not observed in HFD-fed male mice. Furthermore, ovariectomy partially reversed the beneficial Bt effects on host metabolism, indicating a role for sex hormones in mediating probiotic effects. Altogether, these studies highlight the fact that lipids can modulate the gut microbiota resulting in improvement in host metabolism and that PAHSA-induced changes in the microbiota result in at least some of their insulin-sensitizing effects in female mice.
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An abbreviated synthesis of the cell permeable fluorophosphonate-alkyne probe (FP-alkyne) for the broad assessment of serine hydrolase activity has been developed. While FP-alkyne has proven pivotal in numerous chemical biology studies access has relied on a lengthy preparation over nine steps. We have developed a four-step synthesis, starting from commercially available compounds, with three purification steps to provide a new expedited route allowing easy access to a useful tool compound for exploring serine hydrolases chemistry and biology. This route was used in our own studies to generate FP-alkyne which in turn was used to identify the enzyme responsible for Fatty Acid Esters of Hydroxy Fatty Acids (FAHFA) biosynthesis. The use of this route can enable the syntheses of new tool compounds in addition to improving accessibility to FP-alkyne.
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Lipids contribute to the structure, development, and function of healthy brains. Dysregulated lipid metabolism is linked to aging and diseased brains. However, our understanding of lipid metabolism in aging brains remains limited. Here we examined the brain lipidome of mice across their lifespan using untargeted lipidomics. Co-expression network analysis highlighted a progressive decrease in 3-sulfogalactosyl diacylglycerols (SGDGs) and SGDG pathway members, including the potential degradation products lyso-SGDGs. SGDGs show an age-related decline specifically in the central nervous system and are associated with myelination. We also found that an SGDG dramatically suppresses LPS-induced gene expression and release of pro-inflammatory cytokines from macrophages and microglia by acting on the NF-κB pathway. The detection of SGDGs in human and macaque brains establishes their evolutionary conservation. This work enhances interest in SGDGs regarding their roles in aging and inflammatory diseases and highlights the complexity of the brain lipidome and potential biological functions in aging.
Assuntos
Envelhecimento , Lipídeos , Animais , Humanos , Camundongos , Envelhecimento/genética , Anti-Inflamatórios , Encéfalo/metabolismo , Microglia/metabolismo , NF-kappa B/metabolismoRESUMO
Branched fatty acid (FA) esters of hydroxy FAs (HFAs; FAHFAs) are recently discovered lipids that are conserved from yeast to mammals1,2. A subfamily, palmitic acid esters of hydroxy stearic acids (PAHSAs), are anti-inflammatory and anti-diabetic1,3. Humans and mice with insulin resistance have lower PAHSA levels in subcutaneous adipose tissue and serum1. PAHSA administration improves glucose tolerance and insulin sensitivity and reduces inflammation in obesity, diabetes and immune-mediated diseases1,4-7. The enzyme(s) responsible for FAHFA biosynthesis in vivo remains unknown. Here we identified adipose triglyceride lipase (ATGL, also known as patatin-like phospholipase domain containing 2 (PNPLA2)) as a candidate biosynthetic enzyme for FAHFAs using chemical biology and proteomics. We discovered that recombinant ATGL uses a transacylation reaction that esterifies an HFA with a FA from triglyceride (TG) or diglyceride to produce FAHFAs. Overexpression of wild-type, but not catalytically dead, ATGL increases FAHFA biosynthesis. Chemical inhibition of ATGL or genetic deletion of Atgl inhibits FAHFA biosynthesis and reduces the levels of FAHFA and FAHFA-TG. Levels of endogenous and nascent FAHFAs and FAHFA-TGs are 80-90 per cent lower in adipose tissue of mice in which Atgl is knocked out specifically in the adipose tissue. Increasing TG levels by upregulating diacylglycerol acyltransferase (DGAT) activity promotes FAHFA biosynthesis, and decreasing DGAT activity inhibits it, reinforcing TGs as FAHFA precursors. ATGL biosynthetic transacylase activity is present in human adipose tissue underscoring its potential clinical relevance. In summary, we discovered the first, to our knowledge, biosynthetic enzyme that catalyses the formation of the FAHFA ester bond in mammals. Whereas ATGL lipase activity is well known, our data establish a paradigm shift demonstrating that ATGL transacylase activity is biologically important.
Assuntos
Aciltransferases , Ésteres , Ácidos Graxos , Hidroxiácidos , Aciltransferases/genética , Aciltransferases/metabolismo , Tecido Adiposo/química , Tecido Adiposo/metabolismo , Animais , Diglicerídeos , Esterificação , Ésteres/química , Ésteres/metabolismo , Ácidos Graxos/biossíntese , Ácidos Graxos/química , Humanos , Hidroxiácidos/química , Hidroxiácidos/metabolismo , Resistência à Insulina , Camundongos , TriglicerídeosRESUMO
Evaluating novel compounds for neuroprotective effects in animal models of traumatic brain injury (TBI) is a protracted, labor-intensive and costly effort. However, the present lack of effective treatment options for TBI, despite decades of research, shows the critical need for alternative methods for screening new drug candidates with neuroprotective properties. Because natural products have been a leading source of new therapeutic agents for human diseases, we used an in vitro model of stretch injury to rapidly assess pro-survival effects of three bioactive compounds, two isolated from natural products (clovanemagnolol [CM], vinaxanthone [VX]) and the third, a dietary compound (pterostilbene [PT]) found in blueberries. The stretch injury experiments were not used to validate drug efficacy in a comprehensive manner but used primarily, as proof-of-principle, to demonstrate that the neuroprotective potential of each bioactive agent can be quickly assessed in an immortalized hippocampal cell line in lieu of comprehensive testing in animal models of TBI. To gain mechanistic insights into potential molecular mechanisms of neuroprotective effects, we performed a pathway-specific PCR array analysis of the effects of CM on the rat hippocampus and microRNA sequencing analysis of the effects of VX and PT on cultured hippocampal progenitor neurons. We show that the neuroprotective properties of these natural compounds are associated with altered expression of several genes or microRNAs that have functional roles in neurodegeneration or cell survival. Our approach could help in quickly assessing multiple natural products for neuroprotective properties and expedite the process of new drug discovery for TBI therapeutics.
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Produtos Biológicos , Lesões Encefálicas Traumáticas , Fármacos Neuroprotetores , Animais , Produtos Biológicos/uso terapêutico , Linhagem Celular , Modelos Animais de Doenças , Hipocampo/metabolismo , Fármacos Neuroprotetores/uso terapêutico , RatosRESUMO
Branched fatty acid esters of hydroxy fatty acids (FAHFAs) are endogenous lipids with antidiabetic and anti-inflammatory effects. Each FAHFA family consists of esters with different acyl chains and multiple isomers with branch points at different carbons. Some FAHFAs, including palmitic acid hydroxy stearic acids (PAHSAs), improve insulin sensitivity and glucose tolerance in mice by enhancing glucose-stimulated insulin secretion (GSIS), insulin-stimulated glucose transport, and insulin action to suppress hepatic glucose production and reducing adipose tissue inflammation. However, little is known about the biological effects of other FAHFAs. Here, we investigated whether PAHSAs, oleic acid hydroxy stearic acid, palmitoleic acid hydroxy stearic acid, and stearic acid hydroxy stearic acid potentiate GSIS in ß-cells and human islets, insulin-stimulated glucose uptake in adipocytes, and anti-inflammatory effects in immune cells. We also investigated whether they activate G protein-coupled receptor 40, which mediates the effects of PAHSAs on insulin secretion and sensitivity in vivo. We show that many FAHFAs potentiate GSIS, activate G protein-coupled receptor 40, and attenuate LPS-induced chemokine and cytokine expression and secretion and phagocytosis in immune cells. However, fewer FAHFAs augment insulin-stimulated glucose uptake in adipocytes. S-9-PAHSA, but not R-9-PAHSA, potentiated GSIS and glucose uptake, while both stereoisomers had anti-inflammatory effects. FAHFAs containing unsaturated acyl chains with higher branching from the carboxylate head group are more likely to potentiate GSIS, whereas FAHFAs with lower branching are more likely to be anti-inflammatory. This study provides insight into the specificity of the biological actions of different FAHFAs and could lead to the development of FAHFAs to treat metabolic and immune-mediated diseases.
Assuntos
Ésteres/metabolismo , Ácidos Graxos/metabolismo , Adulto , Ésteres/química , Ácidos Graxos/química , Feminino , Glucose/metabolismo , Humanos , Secreção de Insulina , Masculino , Pessoa de Meia-Idade , Estrutura Molecular , EstereoisomerismoRESUMO
Semaphorin3A is considered a classical repellent molecule for developing neurons and a potent inhibitor of regeneration after nervous system trauma. Vinaxanthone and other Sema3A inhibitors are currently being tested as possible therapeutics to promote nervous system regeneration from injury. Our previous study on Sema3A demonstrated a switch in Sema3A's function toward induction of nerve regeneration in adult murine corneas and in culture of adult peripheral neurons. The aim of the current study is to determine the direct effects of Vinaxanthone on the Sema3A induced adult neuronal growth. We first demonstrate that Vinaxanthone maintains its anti-Sema3A activity in embryonic dorsal root ganglia neurons by inhibiting Sema3A-induced growth cone collapse. However, at concentrations approximating its IC50 Vinaxanthone treatment does not significantly inhibit neurite formation of adult peripheral neurons induced by Sema3A treatment. Furthermore, Vinaxanthone has off target effects when used at concentrations above its IC50, and inhibits neurite growth of adult neurons treated with either Sema3A or NGF. Our results suggest that Vinaxanthone's pro-regenerative effects seen in multiple in vivo models of neuronal injury in adult animals need further investigation due to the pleiotropic effect of Sema3A on various non-neuronal cell types and the possible effect of Vinaxanthone on other neuroregenerative signals.
Assuntos
Cones de Crescimento/efeitos dos fármacos , Cones de Crescimento/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Semaforina-3A/metabolismo , Xantonas/farmacologia , Animais , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Camundongos , Neurogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Nervo Trigêmeo/efeitos dos fármacos , Nervo Trigêmeo/metabolismoRESUMO
A series of novel purine linked piperazine derivatives were synthesized to identify new, potent inhibitors of Mycobacterium tuberculosis. The compounds were designed to target MurB disrupting the biosynthesis of the peptidoglycan and exert antiproliferative effects. The first series of purine-2,6-dione linked piperazine derivatives were synthesized using an advanced intermediate 1-(3,4-difluorobenzyl)-7-(but-2-ynyl)-3-methyl-8-(piperazin-1-yl)-1H-purine-2,6(3H,7H)-dione hydrochloride (6) which was coupled with varied carboxylic acid chloride derivatives. Following this piperazine linked derivatives were also synthesized from 6 using diverse isocyanate partners. The anti-mycobacterial activity of the analogues was tested againstMycobacterium tuberculosis H37Rv which revealed a cluster of six analogues (11, 24,27, 32, 33 and34), possessed promising activity. In comparison, a set of these new compounds possessed greater potencies relative to current drugs used in the clinic such as Ethambutol. These results were also correlated with computational molecular docking analysis, providing models for strong interactions of the inhibitors with MurB providing a template for the future development of preclinical agents against Mycobacterium tuberculosis.
Assuntos
Antituberculosos/farmacologia , Desenho de Fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Piperazina/farmacologia , Purinas/farmacologia , Antituberculosos/síntese química , Antituberculosos/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piperazina/síntese química , Piperazina/química , Purinas/síntese química , Purinas/química , Relação Estrutura-AtividadeRESUMO
Eupalinilide E was assessed for ex-vivo expansion activity on hematopoietic stem cells (HSCs) from human cord blood (CB) CD34+ cells in serum-free, SCF, TPO and FL stimulated 7 day cultures. Eupalinilide E ex-vivo enhanced phenotyped (p) HSCs and glycolysis of CD34+ cells isolated 7 days after culture as measured by extracellular acidification rate, but did not alone show enhanced NSG engrafting capability of HSCs as determined by chimerism and numbers of SCID Repopulating cells, a quantitative measure of functional human HSCs. This is another example of pHSCs not necessarily recapitulating functional activity of these cells. Lack of effect on engrafting HSCs may be due to a number of possibilities, including down regulation of CXCR4 or of the homing capacity of these treated cells. However, Eupalinilide did act in an additive to synergistic fashion with UM171 to enhance ex vivo expansion of both pHSCs, and functionally engrafting HSCs. While reasons for the disconnect between pHSC and function of HSCs with Eupalinilide E alone cultured CB CD34+ cells is yet to be determined, the data suggest possible future use of Eupalinilide and UM171 together to enhance ex vivo production of CB HSCs for clinical hematopoietic cell transplantation.
Assuntos
Sangue Fetal/citologia , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Indóis/farmacologia , Pirimidinas/farmacologia , Sesquiterpenos/farmacologia , Animais , Antígenos CD34/análise , Técnicas de Cultura de Células , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citocinas/farmacologia , Sangue Fetal/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Humanos , Camundongos , Camundongos SCIDRESUMO
BACKGROUND: Treatment of schistosomiasis, a neglected disease, relies on just one partially effective drug, praziquantel. We revisited the 9-acridanone hydrazone, Ro 15-5458, a largely forgotten antischistosomal lead compound. METHODS: Ro 15-5458 was evaluated in juvenile and adult Schistosoma mansoni-infected mice. We studied dose-response, hepatic shift and stage specificity. The metabolic stability of Ro 15-5458 was measured in the presence of human and mouse liver microsomes, and human hepatocytes; the latter also served to identify metabolites. Pharmacokinetic parameters were measured in naive mice. The efficacy of Ro 15-5458 was also assessed in S. haematobium-infected hamsters and S. japonicum-infected mice. RESULTS: Ro 15-5458 had single-dose ED50 values of 15 and 5.3 mg/kg in mice harbouring juvenile and adult S. mansoni infections, respectively. An ED50 value of 17 mg/kg was measured in S. haematobium-infected hamsters; however, the compound was inactive at up to 100 mg/kg in S. japonicum-infected mice. The drug-induced hepatic shift occurred between 48 and 66 h post treatment. A single oral dose of 50 mg/kg of Ro 15-5458 had high activity against all tested S. mansoni stages (1-, 7-, 14-, 21- and 49-day-old). In vitro, human hepatocytes produced N-desethyl and glucuronide metabolites; otherwise Ro 15-5458 was metabolically stable in the presence of microsomes or whole hepatocytes. The maximum plasma concentration was approximately 8.13 µg/mL 3 h after a 50 mg/kg oral dose and the half-life was approximately 4.9 h. CONCLUSIONS: Ro 15-5458 has high activity against S. mansoni and S. haematobium, yet lacks activity against S. japonicum, which is striking. This will require further investigation, as a broad-spectrum antischistosomal drug is desirable.
Assuntos
Esquistossomose mansoni , Esquistossomicidas , Acridinas , Animais , Cricetinae , Hidrazonas/uso terapêutico , Camundongos , Schistosoma mansoni , Esquistossomose mansoni/tratamento farmacológico , Esquistossomicidas/uso terapêuticoRESUMO
A promising new compound class for treating human malaria is the imidazolopiperazines (IZP) class. IZP compounds KAF156 (Ganaplacide) and GNF179 are effective against Plasmodium symptomatic asexual blood-stage infections, and are able to prevent transmission and block infection in animal models. But despite the identification of resistance mechanisms in P. falciparum, the mode of action of IZPs remains unknown. To investigate, we here combine in vitro evolution and genome analysis in Saccharomyces cerevisiae with molecular, metabolomic, and chemogenomic methods in P. falciparum. Our findings reveal that IZP-resistant S. cerevisiae clones carry mutations in genes involved in Endoplasmic Reticulum (ER)-based lipid homeostasis and autophagy. In Plasmodium, IZPs inhibit protein trafficking, block the establishment of new permeation pathways, and cause ER expansion. Our data highlight a mechanism for blocking parasite development that is distinct from those of standard compounds used to treat malaria, and demonstrate the potential of IZPs for studying ER-dependent protein processing.
Assuntos
Antimaláricos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Concentração Inibidora 50 , Espectrometria de Massas , Proteínas de Protozoários/metabolismo , Pirazóis/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Via Secretória/efeitos dos fármacosRESUMO
Thiopeptides are a class of natural products with untapped therapeutic potential. To expand the methods available for the scaled production of these antibiotics, we report the laboratory synthesis of micrococcin P1 showcasing thiazole forming reactions of cysteine derivatives and nitriles followed by oxidation. In most instances, this thiazole forming sequence does not require chromatography and proved scalable. Using this approach, 199 mg of micrococcin P1 was generated in a single synthetic sequence.
Assuntos
Bacteriocinas/síntese química , Cisteína/análogos & derivados , Nitrilas/química , Tiazóis/síntese química , Cisteína/química , Tiazóis/químicaRESUMO
Dietary habits have been associated with alterations of the human gut resident microorganisms contributing to obesity, diabetes and cancer1. In Western diets, red meat is a frequently eaten food2, but long-term consumption has been associated with increased risk of disease3,4. Red meat is enriched in N-glycolylneuraminic acid (Neu5Gc) that cannot be synthesized by humans5. However, consumption can cause Neu5Gc incorporation into cell surface glycans6, especially in carcinomas4,7. As a consequence, an inflammatory response is triggered when Neu5Gc-containing glycans encounter circulating anti-Neu5Gc antibodies8,9. Although bacteria can use free sialic acids as a nutrient source10-12, it is currently unknown if gut microorganisms contribute to releasing Neu5Gc from food. We found that a Neu5Gc-rich diet induces changes in the gut microbiota, with Bacteroidales and Clostridiales responding the most. Genome assembling of mouse and human shotgun metagenomic sequencing identified bacterial sialidases with previously unobserved substrate preference for Neu5Gc-containing glycans. X-ray crystallography revealed key amino acids potentially contributing to substrate preference. Additionally, we verified that mouse and human sialidases were able to release Neu5Gc from red meat. The release of Neu5Gc from red meat using bacterial sialidases could reduce the risk of inflammatory diseases associated with red meat consumption, including colorectal cancer4 and atherosclerosis13.
Assuntos
Bactérias/enzimologia , Dieta , Microbioma Gastrointestinal , Ácidos Neuramínicos/metabolismo , Neuraminidase/genética , Polissacarídeos/metabolismo , Carne Vermelha/análise , Animais , Bactérias/classificação , Bacteroides/enzimologia , Bacteroides/genética , Clostridiales/enzimologia , Clostridiales/genética , Cristalografia por Raios X , Fezes/química , Fezes/microbiologia , Feminino , Humanos , Masculino , Metagenômica , Camundongos , Camundongos Endogâmicos C57BL , Neuraminidase/metabolismo , Polissacarídeos/químicaRESUMO
The syntheses of linoleic acid esters of hydroxy linoleic acids (LAHLAs) present in oat oil and human serum have been achieved, providing access to material for testing and the determination of the stereochemistry of the natural compounds. While 9- and 13-LAHLAs were found to be a mixture of enantiomers 15-LAHLA is generated in a single optical form in oat oil. The stereochemistry of 15-LAHLA in oat oil was found to be opposite to that reported for digalactosyldiacylglycerol that possesses an embedded 15-LAHLA.