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The pharmacology of amino acid transporters in the SLC6 family is poorly developed compared to that of the neurotransmitter transporters. To identify new inhibitors of the proline transporter SIT1 (SLC6A20), its expression in Xenopus laevis oocytes was optimized. Trafficking of SIT1 was augmented by co-expression of angiotensin-converting enzyme 2 (ACE2) in oocytes but there was no strict requirement for co-expression of ACE2. A pharmacophore-guided screen identified tiagabine as a potent non-competitive inhibitor of SIT1. To understand its binding mode, we determined the cryo-electron microscopy (cryo-EM) structure of ACE2-SIT1 bound with tiagabine. The inhibitor binds close to the orthosteric proline binding site, but due to its size extends into the cytosolic vestibule. This causes the transporter to adopt an inward-open conformation, in which the intracellular gate is blocked. This study provides the first structural insight into inhibition of SIT1 and generates tools for a better understanding of the ACE2-SIT1 complex. These findings may have significance for SARS-CoV-2 binding to its receptor ACE2 in human lung alveolar cells where SIT1 and ACE2 are functionally expressed.
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Pharmacological research has expanded to the nanoscale level with advanced imaging technologies, enabling the analysis of drug distribution at the cellular organelle level. These advances in research techniques have contributed to the targeting of cellular organelles to address the fundamental causes of diseases. Beyond navigating the hurdles of reaching lesion tissues upon administration and identifying target cells within these tissues, controlling drug accumulation at the organelle level is the most refined method of disease management. This approach opens new avenues for the development of more potent therapeutic strategies by delving into the intricate roles and interplay of cellular organelles. Thus, organelle-targeted approaches help overcome the limitations of conventional therapies by precisely regulating functionally compartmentalized spaces based on their environment. This review discusses the basic concepts of organelle targeting research and proposes strategies to target diseases arising from organelle dysfunction. We also address the current challenges faced by organelle targeting and explore future research directions.
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Antibiotic-resistant Enterobacterales pose a major threat to healthcare systems worldwide, necessitating the development of novel strategies to fight such hard-to-kill bacteria. One potential approach is to develop molecules that force bacteria to hyper-activate prodrug antibiotics, thus rendering them more effective. In the present work, we aimed to obtain proof-of-concept data to support that small molecules targeting transcriptional regulators can potentiate the antibiotic activity of the prodrug metronidazole (MTZ) against Escherichia coli under aerobic conditions. By screening a chemical library of small molecules, a series of structurally related molecules were identified that had little inherent antibiotic activity but showed substantial activity in combination with ineffective concentrations of MTZ. Transcriptome analyses, functional genetics, thermal shift assays, and electrophoretic mobility shift assays were then used to demonstrate that these MTZ boosters target the transcriptional repressor MarR, resulting in the upregulation of the marRAB operon and its downstream MarA regulon. The associated upregulation of the flavin-containing nitroreductase, NfsA, was then shown to be critical for the booster-mediated potentiation of MTZ antibiotic activity. Transcriptomic studies, biochemical assays, and electron paramagnetic resonance measurements were then used to show that under aerobic conditions, NfsA catalyzed 1-electron reduction of MTZ to the MTZ radical anion which in turn induced lethal DNA damage in E. coli. This work reports the first example of prodrug boosting in Enterobacterales by transcriptional modulators and highlights that MTZ antibiotic activity can be chemically induced under anaerobic growth conditions.
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Antibacterianos , Proteínas de Escherichia coli , Escherichia coli , Metronidazol , Nitrorredutases , Proteínas Repressoras , Nitrorredutases/metabolismo , Nitrorredutases/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Escherichia coli/genética , Metronidazol/farmacologia , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Antibacterianos/farmacologia , Antibacterianos/química , Aerobiose , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/químicaRESUMO
Revealing the potential of candidate drugs against different cancer types without disrupting normal cells depends on the drug mode of action. In the current study, the drug response of prostate cancer stem cells (PCSCs) to zoledronic acid (ZOL) grown in two-dimensional (2D) and three-dimensional (3D) culture systems was compared using Fourier transform-infrared (FT-IR) spectroscopy which is a vibrational spectroscopic technique, supporting by biochemical assays and imaging techniques. Based on our data, in 2D cell culture conditions, the ZOL treatment of PCSCs isolated according to both C133 and CD44 cell surface properties induced early/late apoptosis and suppressed migration ability. The CD133 gene expression and protein levels were altered, depending on culture systems. CD133 expression was significantly reduced in 2D cells upon ZOL treatment. FT-IR data revealed that the integrity, fluidity, and ordering/disordering states of the cell membrane and nucleic acid content were altered in both 2D and 3D cells after ZOL treatment. Regular protein structures decrease in 2D cells while glycogen and protein contents increase in 3D cells, indicating a more pronounced cytotoxic effect of ZOL for 2D cells. Untreated 3D PCSCs exhibited an even different spectral profile associated with IR signals of lipids, proteins, nucleic acids, and glycogen in comparison to untreated 2D cells. Our study revealed significant differences in the drug response and cellular constituents between 2D and 3D cells. Exploring molecular targets and/or drug-action mechanisms is significant in cancer treatment approaches; thus, FT-IR spectroscopy can be successfully applied as a novel drug-screening method in clinical research.
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Neoplasias , Próstata , Masculino , Humanos , Ácido Zoledrônico/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Técnicas de Cultura de Células em Três Dimensões , Glicogênio , Células-Tronco Neoplásicas , Linhagem Celular TumoralRESUMO
We recently reported a computational method (IDACombo) designed to predict the efficacy of cancer drug combinations using monotherapy response data and the assumptions of independent drug action. Given the strong agreement between IDACombo predictions and measured drug combination efficacy in vitro and in clinical trials, we believe IDACombo can be of immediate use to researchers who are working to develop novel drug combinations. While we previously released our method as an R package, we have now created an R Shiny application to allow researchers without programming experience to easily utilize this method. The app provides a graphical interface which enables users to easily generate efficacy predictions with IDACombo using provided data from several high-throughput cell line screens or using custom, user-provided data.
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This tutorial defines the concepts of disease progression in the context of clinical pharmacology. Disease progression describes the natural history of disease, such as pain, or biomarker of drug response, such as blood pressure. The action of a drug, such as inhibiting an enzyme or activating a receptor, leads to a change in disease status over time. Two main types of drug response can be defined based on the pattern of the time course of disease status. The most common is a symptomatic effect equivalent to a shift up or down of the natural history curve. Less common but quite clinically important is a disease-modifying effect equivalent to a change in the rate of disease progression.
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Pressão Sanguínea , Progressão da Doença , História Natural , Farmacologia ClínicaRESUMO
This tutorial defines the principles of the concentration - effect relationship which are the basis of pharmacodynamics. The two key parameters of pharmacodynamics are the maximum response (Emax) and the concentration producing 50% of Emax (C₅₀). The time course of effect is illustrated under the assumption that drug effects are immediately related to concentration in the central compartment e.g. plasma. The related idea of duration of drug action and its relationship to dose is shown to have a simple relationship with drug half-life.
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Meia-Vida , PlasmaRESUMO
O Jatobá (Hymenaea courbaril L.) possui um amplo histórico de utilização, seus frutos são compostos por óleos essenciais, taninos, substâncias amargas, matérias resinosas e pécticas, amido e açúcares, O objetivo deste estudo foi avaliar a atividade antimicrobiana e moduladora do óleo essencial extraído da casca de frutos da Hymenaea courbaril L, (OEHc) sobre cepas de S, aureus oxacilina sensíveis (OSSA) de referência, Para a avaliação da atividade antimicrobiana foram determinadas as Concentrações Inibitória (CIM) e Letal Mínimas (CLM) do OEHc e o efeito do tempo de exposição a concentrações do OEHc, o efeito modulador do OEHc sobre antibióticos de uso clínico foi avaliado pelo teste de difusão em ágar modificado, OEHc inibiu o crescimento das cepas de S, aureus ATCC 6538P (CIM = CLM = 0,28% v/v) e S, aureus ATCC 14458 (CIM = 0,28% v/v, CLM = 0,56% v/v), A CLM do OEHc foi capaz de inviabilizar as cepas OSSA testadas em 8 horas (S, aureus ATCC 6538P) e 24 horas (S, aureus ATCC 14458) e a CIM inibiu o crescimento de S, aureus ATCC 14458 até 48h de exposição, A ação moduladora do OEHc na atividade de antibióticos de uso clínico variou com o ATM e com a cepa testada, Os resultados encontrados mostram que o OEHc possui uma boa atividade antimicrobiana sobre a espécie Gram-positivo S, aureus, revelando seu efeito modulador sinérgico quando associado a antibióticos de uso clínico, demonstrando ser o OEHc um forte candidato para o desenvolvimento de fármacos com atividade antimicrobiana...
Jatobá (Hymenaea courbaril L.) has an extensive history of use, its fruits are composed of essential oils, tannins, bitter substances, resinous and pectic materials, starch and sugars. The objective of this study was to evaluate antimicrobial activity and effect of essential oil extracted from the rind of fruits of Hymenaea courbaril l. (OEHc) about reference strains of S. aureus oxacillin susceptible (OSSA). For the evaluation of antimicrobial activity were determined Inhibitory (MIC) and Lethal (CLM) Minimum Concentrations from OEHc and the effect of time of exposure to concentrations of OEHc, OEHc modulator effect on antibiotics of clinical use was assessed by modified agar diffusion test. OEHc inhibited the growth of S. aureus strains ATCC 6538P (CIM = CLM = 0,28% v/v) and S. aureus ATCC 14458 (CIM = 0,28% v/v; CLM = 0,56% v/v). The CLM from OEHc was able to derail the OSSA strains tested in 8 hours (S. aureus ATCC 6538P) and 24 hours (S. aureus ATCC 14458) and the CIM inhibited the growth of S. aureus ATCC 14458 until 48 hours of exposure. The modulatory action of the antibiotic activity of OEHc clinical use ranged with the ATM and with the strain tested. The results show that the OEHc has a good antimicrobial activity on the species Gram-positive S. aureus, revealing its synergistic modulator effect when associated with antibiotics of clinical use, demonstrating the OEHc a strong candidate for the development of drugs with antimicrobial activity...
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Humanos , Sinergismo Farmacológico , Hymenaea/microbiologia , Óleos Voláteis , Testes de Sensibilidade Microbiana , Plantas MedicinaisRESUMO
Objective: To observe effects of Yuzhang Decoction on in vitro proliferation of bone marrow CD_(34) cells in the patient of aplastic anemia (CAA) and its mechanism. Methods: To adopt monoclone antibody-immune magnetic beads separation system (MACS) to separate and purify CD_(34) cells in bone marrow of the patient of CAA, and make cell culture, applying ~3H-TdR incorporation to detect effect of Yuzhang Decoction on proliferation of CD_(34) cells of bone marrow. Results: CD_(34) cells of bone marrow showed concentration-dependent proliferation in the Yuzhang Decoction group with significantly differences (P
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By applying advanced technique such as cytological CT the action of 926, a Chinese drug, on ascitis cervical cancer cells was observed. Results revealed that it destroys the DNA and RNA of cancer cell, prevent it from synthesis of nucleic acid and cellular proliferation. These has upgraded the experimental research to a new level.
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By counting the amount of microbes inoculation of superficial fungus and MIC determination, 10 kinds of herbs distributed in China were observed for their bacteriostatic actions on 8 kinds of common superficial fungal infections. Among them, 5% water extracts from Cortex Moutan Radicis, Herba Artemisia, Cortex Dictamni Radicis, Cortex Fraxini Rhizoma Belamcandae and Radix Notopterigii, their average MIC were 11. 88%, indicating that they can be applied as wide - spectrum antifungal herbs for superficial mycotic infection.
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The experiment was conducted on the actions of 5 kinds of reagents on HL - 60 cellular wither, viz. Yisuiling chloroform extract, rabbit serum chloroform extract, rabbit liver paste chloroform extract, Etoposide, and normal rabbit serum. Results revealed that after fluid incubation for a short period, the HL-60 cultured cells showed no wither in the former 4 groups under microscope and flowing cytometer. Among them, action was strongest in rabbit liver paste of Yisuiling extract group, similar to the positive control of Etoposide. Followed by rabbit serum, and the action was weak in Yisuiling chloroform extract. There was no obvious action of induced wither by normal rabbit serum. The mechanism of induced wither is still under investigation.
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In order to study on the theory of " phlegm and blood stasis having same source" and effects of drugs for resolving phlegm on blood rheology, effects of Ban Xia, Gua Lou, Zhe Bei Mu and Shi Chang Pu on whole blood viscosity, erythrocyte deformation index and plasma fibrinogen content in normal rats. Results indicated that the drugs.for resolving phlegm had functions of decreasing whole blood viscosity, inhibiting hemoagglutination (except Gua Lou) and increasing capability of erythrocyte deformation; at high shearing rate, Shi Chang Pu and Zhe Bei Mu could slightly increase whole blood viscosity: Shi Chang Pu increased slightly plasma fibrinogen content. It is suggested that resolving phlegm also can removing blood stasis, and the mechanism of the drug for resolving phlegm in decreasing blood viscosity is related with decrease of blood lipids and anti - peroxidation of lipids.
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Objective:To observe effects of Fuzheng Huoxue Recipe on blood growth hormone (GH) and insulin growth factor(IGF-1) in chronic renal failure(CRF) rats.Methods:Platt method was adopted to make 5/6 kidney excision CRF model rat,and the rats were divided into model group,Huangqi group,Enalapril group,Danshen group,Fuzheng Huoxue Recipe group and normal control group according to the blood creatinine level after modeling.Effects of Fuzheng Huoxue Recipe on GH and IGF-1 levels in CRF rats with large quantity of urinal protein were investigated.Results:GH and IGF-1 levels in the model control group were significantly higher than that in normal control group,and after treatment of Fuzheng Huoxue Recipe,blood GH and IGF-1 levels were significantly decreased.Conclusion:Fuzheng Huoxue Recipe can decrease blood GH and IGF-1 levels in CRF rats,and can delay advances of CRF.
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The Decoction showed marked effect on manykinds of Icterus Neonatorum,Estimation on the activi-ty of superoxide dimutase,lipoperoxide,enzymes ofRBC,were made through histochemical staining andresistance of RBC membrane.Results revealed thatthe remedy has distinctive protective action on cellmembrane of RBC.
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Two hundred cases of early pregnant women to receiveartificial abortion were randomly divided into 4groups,viz.analgesic solution,dicaine,normal saline,and blank control groups of which the action on dilata-tion of uterus and of mitigating the comprehensive re-actions to artificval abortion were observed.Resultsrevealed that the analgesic solution and dicaine groupshad better effect on dilatation of uterus and ameliorat-ing the reactions of artificial abortion,analgesic solu-tion was especially good at mitigating the comprehen-sive reactions to artificial abortion than the dicainegroup.
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Objective:To study effects of 5 recipes for tonifing and supplementing on apoptosis and splenocytes in mice treated with cyclophosphamide.Methods:Apoptosis and cellular cycles of splenocytes were detected by flowcytometric analysis.Results:Sijunzi Decoction,Liuwei Dihuang Pill,Shengmai Powder,Jingui Shenqi Pill could antagonize the decline of proliferation induced by cyclophosphamide,and Sijunzi Decoction and Liuwei Dihuang Pill could resist the apoptosis of splenocytes caused by cyclophosphamide;and the recipes all could inhibit atrophy of the spleen induced by cyclophosphamide Conclusion:The 5 recipes for tonifying and supplementing all can improve the injury of the spleen induced by cyclopbosphamide in varying degrees,Sijunzi Decoction and Liuwei Dihuang Pill being the best.
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Objective:To observe effects of Shenkui Decoction on proliferation of ovarian cancer cell.Methods:The Shenkui Decoction- containing rat serum was prepared by using TCM serum pharmacological method,and effects of the drug containing serum on proliferation of ovarian cancer fresh parenchymatous tumor cells were investigated with 3H incorporation method,and effects of the drug-containing serum on proliferation of ovarian cancer cell line Tyk-nu cells were investigated by flow cytometry,cellular activity assay,cellular growth curve assay and cell colony formation rate assay.Results:The drug containing serum could inhibit proliferation of both fresh parenckymatous tumor cells and ovarian cancer cell line Tyk-nu cells,and the inhibitory rate raised with the increase of drug-containing serum content.Conclusion:The Shenkui Decoction-containing rat serum can inhibit proliferation of ovarian cancer fresh parenchymatous tumor cells and ovarian cancer cell line Tyk-nu cells.
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Objective:To study on effect of Jiantai Liquid on progesterone receptor(PR)in the uterus at the nidation stage in the mouse with disturbance of blastocyst nidation.Methods:The gestational mice were randomly divided into a normal group,a model group and a Chinese drug group.Mifepristone was used for inducing disturbance of blastocyst nidation in the mice,which were interfered with Jiantai Liquid.At the eighth week of pregnancy,the mice were killed and morphological changes of the endometrium were observed,and PR expression in the uterus was detected with immunohistochemical method and PR and PRmRNA expressions were detected with Western blot and PT-PCR methods.Results:The endometrium showed maldevelopment in the model group and normal development in the Chinese drug group,similar to the normal group;the gland,the PR expression range and intensity of PR expression in the interstitial substance in the Chinese drug group increased as compared with the model group(P0.05);expressions of PR protein and gene in the Chinese drug group were significantly higher than those in the model group(P0.05).Conclusion:Jiantai Liquid can promote development of the endometrium and improves blastocyst nidation via regulating expressions of PR and PRmRNA in the uterus in the mice with disturbance of blastocyst nidation.
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Objective:To observe effect of Xiaoyu Zhixue Tablets on expression of platelet membrane glucoprotein in the patient of hemorrhagic thrombopathy and probe into the mechanism of the therapy.Methods:148 cases of hemorrhagic thrombopathy were randomly divided into a Chinese drug group(n=98)treated by Xiaoyu Zhixue Tablets,and a Western medicine group(n=50) treated by adrenosem,vitamine C,K,P.They were treated for 6 months.After treatment the therapeutic effect of hemostasis and the recovery rate of platelet aggregation in the two group were observed and analyzed.Before and after treatment expressions of platelet membrane glucoproteins GP Ⅰ b/Ⅸ,GP Ⅱ b/Ⅲa,GP Ⅰ b,GP Ⅱ b,GP Ⅲ a and p-selectin expression were detected with flow cytometry in the two groups and in 34 healthy persons(normal group).Results:The total effecive rate of hemostasis was 89. 8% in the Chinese drug group and 54.0% in the Western medicine group,and the recovery rate of platelet aggegation was 72.4% in the Chinese drug group and 4.0% in the Western medicine group,with significant differences(both P0.05).Conclusion:Xiaoyu Zhixue Tablets can up-regulate platelet membrane glucoproteins GP Ⅰ b/Ⅸ,GP Ⅱ b/Ⅲ a,GP Ⅰ b,GP Ⅲ a and p-selectin expression,which is possibly one of the mechanisms for treatment of hemorrhagic thrombopathy.