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Photodynamic therapy (PDT) is a well-established treatment modality, typically conducted with single-wavelength irradiation, which may not always be optimal for varying tumor locations and sizes. To address this, photosensitizers with absorption wavelengths ranging from 550 to 760 nm are being explored. Herein, a series of 5,15-diaryltetrabenzoporphyrins (Ar2TBPs) were synthesized. All compounds displayed obvious absorption at 550-700 nm (especially at â¼668 nm), intense fluorescence, efficient generation of singlet oxygen and good photodynamic antitumor effects. Notably, compound I3 (5,15-bis[(4-carboxymethoxy)phenyl]tetrabenzoporphyrin) showed excellent cytotoxicity against Eca-109 cell line upon red light irradiation, with an IC50 value of 0.45 µM, and phototherapeutic index of 25.8. Flow cytometry revealed that I3 could induce distinct cell apoptosis. In vivo studies revealed that compound I3 selectively accumulated at tumor site and exhibited outstanding PDT effect with antitumor activity under single-time administration and light irradiation, and revealed more efficiency than the clinical photosensitizer Verteporfin. These findings underscore the considerable promise of I3 as a robust theranostic agent, offering capabilities in real-time fluorescence imaging and serving as a potent photosensitizer for personalized and precise photodynamic therapy of tumors.
Assuntos
Antineoplásicos , Apoptose , Ensaios de Seleção de Medicamentos Antitumorais , Fotoquimioterapia , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Animais , Estrutura Molecular , Camundongos , Relação Estrutura-Atividade , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Verteporfina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Porfirinas/química , Porfirinas/farmacologia , Porfirinas/síntese químicaRESUMO
Aim: A study of the enhancement of photodynamic activities of pyropheophorbide-a using PG-Ag-PPa nanoconjugates. Materials & methods: The nanoconjugates were formulated from silver nanoparticles and PPa via amide linkage, then characterized, and their photodynamic activities were examined. Results: The nanoconjugates displayed a higher rate of reactive oxygen species generation, commendable cellular uptake by Eca-109 cancer cells, higher photocytotoxicity toward the cancer cells and better bio-safety. They revealed strong antibacterial activity against Escherichia coli following internal reactive oxygen species generation and membrane disintegration. The in vivo anticancer studies confirmed higher cytotoxicity of the nanoconjugates toward cancer cells and better safety than PPa. Conclusion: Therefore, PG-Ag-PPa nanoconjugates could be considered potential nano photosensitizers for photodynamic therapy of tumors and bacterial infection with good bio-safety.
[Box: see text].
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To discover effective photosensitizers for photodynamic therapy (PDT), a series of new meso-tetraphenyltetrabenzoporphyrin (m-Ph4TBP) derivatives were designed, prepared, and characterized. All m-Ph4TBPs own two characteristic absorption bands in the range of 450-500 and 600-700 nm and have the ability to generate singlet oxygen upon photoexcitation. Most of the m-Ph4TBPs demonstrated high photoactivity, among which compounds I4, I6, I12, and I13 induced apoptosis and also exhibited excellent photodynamic activities in vivo. Nonetheless, the liver organs of the I4 and I6-PDT groups showed clear calcifications, whereas the liver tissues of the other PDT groups showed no calcification. It was indicated that compared to phenolic m-Ph4TBPs, glycol m-Ph4TBPs exhibited superior biological safety in mice. According to comprehensive evaluations, m-Ph4TBP I12 displayed excellent photodynamic antitumor efficacy and biological safety and can be regarded as a promising antitumor drug candidate.
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In quest for new photosensitizers (PSs) with remarkable antitumor photodynamic efficacy, a series of fifteen quaternary ammonium (QA) cations conjugated 5,15-diaryltetranaphtho[2,3]porphyrins (Ar2TNPs) was synthesized and evaluated in vitro and in vivo to understand how variations in the length of the alkoxy group and the kind of QA cations on meso-phenyl influence the photodynamic antitumor activity. All final compounds (I1-5, II1-5, and III1-5) exhibited robust absorption at 729 nm with significant bathochromic shift and high molar extinction coefficients (1.16 × 105-1.41 × 105 M-1 cm-1), as well as other absorptions at 445, 475, 651, and 714 nm for tumors and other diseases of diverse sizes and depths. Upon exposure to 474 nm light, they displayed intense fluorescence emission with fluorescence quantum yields ranging from 0.32 to 0.43. The ability to generate reactive oxygen species (ROS) was also quantified, attaining a maximum rate of up to 0.0961 s-1. The IC50 values of all the compounds regarding phototoxicity and dark toxicity were determined using KYSE-150 cells, and the phototoxicity indices were calculated. Among these compounds, III1 demonstrated the highest phototoxic index with minimal dark toxicity, and suppressed successfully the growth of esophageal carcinoma xenograft with favorable tolerance in vivo. Furthermore, the histological results showed III1-mediated PDT had a significant cytotoxic effect on the tumor. These outcomes underscore the potential of III1 as a highly effective antitumor photosensitizer drug in photodynamic therapy (PDT).
Assuntos
Compostos de Amônio , Fotoquimioterapia , Porfirinas , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fotoquimioterapia/métodos , Porfirinas/farmacologia , CátionsRESUMO
To discover new photosensitizers with long wavelength UV-visible absorption, high efficiency, and low side effects for photodynamic therapy, here, a series of novel thieno[3,2-b]thiophene-fused BODIPY derivatives were designed, synthesized and characterized. These compounds had a distinct absorption band at 640-680 nm, fluorescence emission at 650-760 nm, and good solubility with anti-aggregation effects. These new compounds possessed obvious singlet oxygen generation ability and photodynamic anti-Eca-109 cancer cells activities in vitro. Among them, compound II4 could be well uptaked by Eca-109 cells, and result in the apoptosis after laser irradiation, and have outstanding photodynamic efficiency both in vitro and in vivo. Therefore, II4 could be considered as a potential photosensitizer drug candidate for PDT and photo-imaging.
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Compostos de Boro , Fotoquimioterapia , Fotoquimioterapia/métodos , Solubilidade , Tiofenos/farmacologia , Fármacos Fotossensibilizantes/farmacologiaRESUMO
The discovery of new photosensitizer drugs with long wavelength Uv-vis absorption, high efficiency and low side-effects is still a challenge in photodynamic therapy. Here a series of novel meso-substitutedphenyl thieno[3,2-b]thiophene-fused BODIPY derivatives were designed, synthesized and characterized. All these compounds have strong absorption at 640-680 nm and obvious fluorescence emission at 650-760 nm. They exhibited high singlet oxygen generation ability and significant photodynamic efficiency against Eca-109 cancer cells. Compounds II4, II6, II9, II10 and II13 could generate intracellular ROS and induce cell apoptosis after laser irradiation, which displayed superior photodynamic efficiency against Eca-109 cells than Temoporfin in vitro and in vivo. Among them, compound II4 specifically exhibited excellent anti-tumor efficacy, and could be selected as a new drug candidate for PDT.
Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/farmacologia , Tiofenos/farmacologia , Compostos de Boro/farmacologia , Oxigênio SingleteRESUMO
In the pursuit of new potent photosensitizers (PSs) for photodynamic therapy (PDT) with better efficacy, a series of 5,15-diaryltetranaphtho [2,3]porphyrins (Ar2TNPs) with two or four carboxyalkoxy groups were designed, synthesized, and evaluated. These new compounds exhibited strong, broad and red-shifted UV-vis absorptions at 729 nm and other strong absorptions at 446, 475, 650, 659, 714 nm for tumors and other diseases of varying sizes and depths. They possess high molar extinction coefficients (0.95 × 105-1.48 × 105 M-1 cm-1), good singlet oxygen quantum yields and photodynamic antitumor effects towards Eca-109 cells in vitro. It is suggested that the extension of porphyrin with naphthalene into Ar2TNP results into remarkable improvement of photophysical characteristics, while the introduction of carboxyalkoxy groups on meso-phenyl can significantly improve the solubility and photodynamic effects in vitro and in vivo. Notably, compound II3 can localize primarily in lysosomes of Eca-109 cells and induce substantial cell apoptosis after PDT. It can also selectively accumulate in tumor tissues and be traced real-timely through in vivo fluorescence imaging with distinctive inhibition of tumor growth. Therefore, compound II3 deserves to be considered as a promising PDT drug candidate for individualized tumor real-time tracing and treatment.
Assuntos
Neoplasias , Fotoquimioterapia , Porfirinas , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fotoquimioterapia/métodos , Porfirinas/farmacologia , ApoptoseRESUMO
Background: Photodynamic therapy (PDT) of cancer has been limited by the poor solubility of most photosensitizers, use of high drug dosages, and the pH difference between the tumor tissue microenvironment (slightly acidic) and the bloodstream. These affect cellular uptake, selectivity and singlet oxygen generation. Materials & methods: We formulated Photinia glabra-green synthesized zinc oxide-protoporphyrin IX (PG-ZnO-PP) nanoconjugates by conjugating the ZnO nanoparticles enriched with amino groups and PP. Results: PG-ZnO-PP nanoconjugates showed higher rate of reactive oxygen species generation, improved cellular uptake in the acidic pH and lower IC50 toward Eca-109 cells for PDT. Conclusion: PG-ZnO-PP nanoconjugates are a potential solution to reducing drug dosage of PP through improved drug uptake, for enhanced targetability and reduced skin photosensitivity with improved PDT efficacy.
The progress of treating cancer using light-sensitive drugs and laser light of known wavelength has been limited by the poor solubility of most light-sensitive drugs, the use of high drug dosages and the slightly acidic environment within the cancerous tissues compared with normal blood in the body. These affect the ability of drugs to accumulate in cancerous cells, and not the normal cells, and the ability to produce the oxygen species that are toxic to the cancerous cells. In this paper, we prepared nanoparticles from zinc acetate using Photinia glabra (PG) fruit extract which were then used to chemically react with a light-sensitive drug called protoporphyrin IX (PP) to formulate small particles known as PGzinc oxide (ZnO)PP nanoconjugates. Our results showed that PGZnOPP nanoconjugates had the ability to produce the toxic oxygen particles at a high rate and in good quantity. They also had a higher capability to accumulate in the cancerous cells at a pH below 7 with lower values of the drug needed to cause 50% of cell death toward the cancerous cells which affect the tube that connects from the throat to the stomach when projected with laser light. We could consider PGZnOPP nanoconjugates to serve as a potential solution for reducing the dosage of PP needed to treat cancer in the presence of laser light, and at the same time they can help to reduce the skin-related side effects for patients after treatment when exposed to light.
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Neoplasias , Photinia , Fotoquimioterapia , Protoporfirinas , Óxido de Zinco , Nanoconjugados , Óxidos , Fármacos Fotossensibilizantes/farmacologia , Linhagem Celular Tumoral , Concentração de Íons de Hidrogênio , Neoplasias/tratamento farmacológicoRESUMO
Pattern-recognition receptor (PRR)-triggered immunity (PTI) wards off a wide range of pathogenic microbes, playing a pivotal role in angiosperms. The model liverwort Marchantia polymorpha triggers defense-related gene expression upon sensing components of bacterial and fungal extracts, suggesting the existence of PTI in this plant model. However, the molecular components of the putative PTI in M. polymorpha and the significance of PTI in bryophytes have not yet been described. We here show that M. polymorpha has four lysin motif (LysM)-domain-containing receptor homologs, two of which, LysM-receptor-like kinase (LYK) MpLYK1 and LYK-related (LYR) MpLYR, are responsible for sensing chitin and peptidoglycan fragments, triggering a series of characteristic immune responses. Comprehensive phosphoproteomic analysis of M. polymorpha in response to chitin treatment identified regulatory proteins that potentially shape LysM-mediated PTI. The identified proteins included homologs of well-described PTI components in angiosperms as well as proteins whose roles in PTI are not yet determined, including the blue-light receptor phototropin MpPHOT. We revealed that MpPHOT is required for negative feedback of defense-related gene expression during PTI. Taken together, this study outlines the basic framework of LysM-mediated PTI in M. polymorpha and highlights conserved elements and new aspects of pattern-triggered immunity in land plants.
Assuntos
Embriófitas , Magnoliopsida , Marchantia , Quitina , Reconhecimento da Imunidade Inata , Marchantia/genética , Lisina/química , Lisina/genéticaRESUMO
Aims: We prepared Photinia glabra (PG) aqueous fruit extract, utilized it to synthesize silver nanoparticles (PG-Ag NPs) and evaluated the antibacterial and anticancer activities of the nanoparticles (NPs). Materials & methods: Silver nitrate aqueous solution was reduced to PG-Ag NPs using aqueous PG fruit extract. NP shape, size, composition and functionalization were determined using transmission electron microscopy, x-ray photoelectron spectroscopy, Fourier transform infrared and x-ray diffraction. Results & conclusions: PG-Ag NPs were spherical, approximately 39-77 nm-sized, functionalized surfaces with notable antibacterial activity against both Escherichia coli and Staphylococcus aureus, with an MIC <30 ug/ml and cytotoxicity toward esophageal cancer cells, with IC50 values less than 20 ug/ml. PG-Ag@rt NPs have been shown to be a potent antibacterial and anticancer agent, and their enriched particle surfaces can be conjugated with other compounds for multibiomedical applications.
The present study reports for the first time the preparation of Photinia glabra (PG) aqueous fruit extract and its use for the synthesis of smaller silver particles (PG-Ag NPs) from bulk aqueous silver nitrate solution (AgNO3). The preparation followed the reduction ability of PG fruit extract phytochemical under different preparation conditions: at room temperature (PG-Ag@rt), at 70°C (PG-Ag@70) and in the presence of cerium oxide at 70°C (PG-Ag+CeO2@70). The prepared smaller particles were found using transmission electron microscopy to be spherical in shape with sizes 39, 77 and 44 nm for PG-Ag@rt, PG-Ag@70 and PG-Ag+CeO2@70, respectively. The NPs contained different functional groups on their surfaces due to the capping ability of PG fruit extract components. Among all, PG-Ag@rt NPs showed strongest antibacterial activity against Escherichia coli and Staphylococcus aureus with MIC 7.0 µg/ml and 28.0 µg/ml, respectively, and commendable anticancer activity toward Eca-109 cancer cells with IC50 less than 20 ug/ml.
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Antibacterianos , Antineoplásicos , Nanopartículas Metálicas , Prata , Antibacterianos/farmacologia , Frutas/química , Nanopartículas Metálicas/química , Photinia/química , Extratos Vegetais/química , Prata/farmacologia , Antineoplásicos/farmacologiaRESUMO
The synthesis of ideal photosensitizers (PSs) is considered to be the most significant bottleneck in photodynamic therapy (PDT). To discover novel PSs with excellent photodynamic anti-tumor activities, a series of novel photosensitizers 5,15-diaryl-10,20-dibromoporphyrins (I1-6) were synthesized by a facile method. Compared with hematoporphyrin monomethyl ether (HMME) as the representative porphyrin-based photosensitizers, it is found that not only the longest absorption wavelength of all compounds was red-shifted to therapeutic window (660 nm) of photodynamic therapy, but also the singlet oxygen quantum yields were significantly increased. Furthermore, all compounds exhibited lower dark toxicity (except I2) and stronger phototoxicity (except I4) against Eca-109 tumor cells than HMME. Among them, I3 possessed the highest singlet oxygen quantum yield (ΦΔ = 0.205), the lower dark toxicity and the strongest phototoxicity (IC50 = 3.5 µM) in vitro. The findings indicated the compounds I3 had the potential to become anti-tumor agents for PDT.
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Neoplasias , Fotoquimioterapia , Porfirinas , Humanos , Fármacos Fotossensibilizantes/química , Oxigênio Singlete/química , Porfirinas/química , Neoplasias/tratamento farmacológicoRESUMO
Photodynamic therapy (PDT) is a promising new treatment for cancer; however, the hydrophobic interactions and poor solubility in water of photosensitizers limit the use in clinic. Nanoparticles especially carbon dots have attracted the attention of the world's scientists because of their unique properties such as good solubility and biocompatibility. In this paper, we integrated carbon dots with different porphyrins to improve the properties of porphyrins and evaluated their efficacy as PDT drugs. The spectroscopic characteristics of porphyrins nano-conjugates were studied. Singlet oxygen generation rate and the light- and dark-induced toxicity of the conjugates were studied. Our results showed that the covalent interaction between CDs and porphyrins has improved the biocompatibility. The synthesized conjugates also inherit the pH sensitivity of the carbon dots, while the conjugation also decreases the hemolysis ratio making them a promising candidate for PDT. The incorporation of carbon dots into porphyrins improved their biocompatibility by reducing toxicity.
Assuntos
Fotoquimioterapia , Porfirinas , Carbono/química , Concentração de Íons de Hidrogênio , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologiaRESUMO
BACKGROUND: A green emission up-conversion carbon-based polymer dots (CPDs) owned excellent photophysical properties and good solubility. Most photosensitizers (PS) are hydrophobic which limits their application in biomedicine. Herein we synthesized and integrated green emitting CPDs into pyropheophorbide-α (PPa) to improve the overall properties of the PS. MATERIAL AND METHODS: The nano-agent was incorporated through amide condensation and electrostatic interaction. The structure, size and morphology of the prepared conjugates were determined by FTIR, TEM, DLS, TGA, 1HNMR, Uv-vis, and fluorescence spectrophotometry. The dark and light toxicity, as well as cellular uptake, was also monitored on the human esophageal cancer cell line (Eca-109). RESULTS: Our results illustrate that the conjugation improved the PDT efficacy by increasing the ROS generation. The nano-hybrids showed pH sensitivity as well as good hemocompatibility as the hemolysis ratio was decreased when treated with nano-conjugates. PPa-CPD1 and PPa-CPD2 had the pH response and stronger ability to absorb light and produce fluorescence in an acidic environment (pH 4.0 and pH 5.0) The synthesized nano-hybrids doesnot affect the clotting time. An increase in the absorbance wavelengths was observed. The results of MTT assay showed that dark toxicity was reduced after conjugation. CONCLUSION: This CPDs-based drug enhanced tumor-inhibition efficiency as well as low dark toxicity in vitro, showing significant application potential for PDT-based treatment.
Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Neoplasias/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , PolímerosRESUMO
BACKGROUND: Photodynamic therapy has been increasingly used to cope with the alarming problem of cancer. Porphyrins and their derivatives are widely used as Potent Photosensitizers (PS) for PDT. However, the hydrophobicity of porphyrins poses a challenge for their use in clinics, while most of the carbon dots (CDs) are known for good biocompatibility, solubility, and pH sensitivity. OBJECTIVE: This study aimed to improve the properties/biocompatibility of the pyropheophorbide-α for PDT. METHODS: The PPa-CD conjugate was synthesized through covalent interaction using amide condensation. The structure of synthesized conjugate was confirmed by TEM, 1HNMR, and FTIR. The absorption and emission spectra were studied. In vitro, cytotoxicity of the conjugate was examined in human esophageal cancer cell line (Eca-109). RESULTS: The results showed that the fluorescence of the drug was increased compared to its precursor. CDbased conjugate could generate ROS as well as enhanced biocompatibility by decreasing cytotoxicity. The conjugated drug also showed pH sensitivity in different solutions. CONCLUSION: The dark toxicity, as well as hemocompatibility, was improved.
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Neoplasias , Fotoquimioterapia , Porfirinas , Carbono/química , Linhagem Celular Tumoral , Humanos , Concentração de Íons de Hidrogênio , Neoplasias/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/farmacologiaRESUMO
Environmental information is required to stabilize estimates of head direction (HD) based on angular path integration. However, it is unclear how this happens in real-world (visually complex) environments. We present a computational model of how visual feedback can stabilize HD information in environments that contain multiple cues of varying stability and directional specificity. We show how combinations of feature-specific visual inputs can generate a stable unimodal landmark bearing signal, even in the presence of multiple cues and ambiguous directional specificity. This signal is associated with the retrosplenial HD signal (inherited from thalamic HD cells) and conveys feedback to the subcortical HD circuitry. The model predicts neurons with a unimodal encoding of the egocentric orientation of the array of landmarks, rather than any one particular landmark. The relationship between these abstract landmark bearing neurons and head direction cells is reminiscent of the relationship between place cells and grid cells. Their unimodal encoding is formed from visual inputs via a modified version of Oja's Subspace Algorithm. The rule allows the landmark bearing signal to disconnect from directionally unstable or ephemeral cues, incorporate newly added stable cues, support orientation across many different environments (high memory capacity), and is consistent with recent empirical findings on bidirectional HD firing reported in the retrosplenial cortex. Our account of visual feedback for HD stabilization provides a novel perspective on neural mechanisms of spatial navigation within richer sensory environments, and makes experimentally testable predictions.
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Modelos Neurológicos , Orientação/fisiologia , Navegação Espacial/fisiologia , Algoritmos , Animais , Biologia Computacional , Simulação por Computador , Sinais (Psicologia) , Meio Ambiente , Retroalimentação Sensorial/fisiologia , Giro do Cíngulo/fisiologia , Cabeça/fisiologia , Vias Neurais/fisiologia , Tálamo/fisiologiaRESUMO
Carbon based polymer dots have piqued attention of researchers because of excellent biocompatibility, and good solubility. Most of the p-dots are able to generate ROS which is effective for photodynamic therapy for the treatment of cancer while some photosensitizers such as porphyrins possess some drawbacks such as hydrophobicity, and dark toxicity. Therefore in this study we conjugated red emission carbon based polymer with pyropheophorbide-α through amide condensation and π-π stacking. One pot synthesis of the conjugate was successfully achieved. Their photophysiological properties were studied and structures were characterized by FT-IR, TEM and 1HNMR. pH- sensitivity of the conjugates was confirmed using fluorescence and UV-vis spectroscopy. Photo toxicity and dark toxicity of the prepared conjugates were evaluated in human esophageal cancer cell line (Eca-109). Hemocompatibility of the synthesized conjugates was evaluated and proved that the conjugates are safe to use for the treatment of tumor. Our results showed the PS doped p-dots had less dark toxicity and increased light toxicity as well as ROS generation was high as compared to precursor drug. Therefore, incorporation of p-dots to porphyrin improved biocompatibility and enhanced the photodynamic effect.
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BACKGROUND: Antibiotic resistance is increasing day by day, thereby increase the chances of more infections by resistant bacteria. In this situation, antimicrobial photodynamic therapy (aPDT) is gaining more attraction. OBJECTIVE: To evaluate the antimicrobial effect of ALA derivatives using photodynamic therapy. MATERIALS AND METHODS: In this study, we evaluated the aPDT effect of different derivatives of 5-ALA. In vivo and in vitro studies were performed to measure the antimicrobial activity. Different light doses and different concentrations of drugs were used to test anti-bacterial effect of drugs as well as to detect any physiological changes in animal model after the treatment. RESULTS: In vivo studies revealed that ALA-methyl ester, ALA-hexyl ester, and ALA-13A are potent photosensitizers. In vitro studies involved wound healing rate, body weight, and dietary intake were evaluated, and results showed that ALA, ALA-methyl ester, ALA-hexyl ester, and ALA-13A had good anti-bacterial effects, fast healing rate, and no effect on other physical parameters. CONCLUSION: Photodynamic therapy is increasingly used to treat different types of skin infections caused by bacterial strains. Our studies revealed that ALA-methyl ester, ALA-hexyl ester, and ALA-13A are promising photosensitizers for photodynamic therapy to inhibit the growth of resistant bacterial strains.
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Anti-Infecciosos , Fotoquimioterapia , Ácido Aminolevulínico/farmacologia , Animais , Anti-Infecciosos/farmacologia , Ésteres , Preparações Farmacêuticas , Fármacos Fotossensibilizantes/farmacologiaRESUMO
A photosensitizer with high phototoxicity, suitable amphipathy and low dark toxicity could play a pivotal role in photodynamic therapy (PDT). In this study, a facile and versatile approach was adopted to synthesize a series of novel fluorinated hematoporphyrin ether derivatives (I1-I5 and II1-II4), and the photodynamic activities of these compounds were studied. Compared to hematoporphyrin monomethyl ether (HMME), all PSs showed preferable photodynamic activity against A549 lung tumor cells. The longest visible absorption wavelength of these compounds was approximately 622 nm. Among them, II3 revealed the highest singlet oxygen yield (0.0957 min-1), the strongest phototoxicity (IC50 = 1.24 µM), the lowest dark toxicity in vitro, and exhibited excellent anti-tumor effects in vivo. So compound II3 could act as new drug candidate for photodynamic therapy.
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Antineoplásicos/uso terapêutico , Éteres/uso terapêutico , Hematoporfirinas/uso terapêutico , Hidrocarbonetos Fluorados/uso terapêutico , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Células A549 , Animais , Antineoplásicos/síntese química , Antineoplásicos/efeitos da radiação , Teoria da Densidade Funcional , Éteres/síntese química , Éteres/efeitos da radiação , Feminino , Hematoporfirinas/síntese química , Hematoporfirinas/efeitos da radiação , Humanos , Hidrocarbonetos Fluorados/síntese química , Hidrocarbonetos Fluorados/efeitos da radiação , Luz , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Químicos , Neoplasias/patologia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/efeitos da radiação , Oxigênio Singlete/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
A series of new fluoro-substituted benzimidazole derivatives were designed, synthesized and pharmacologically evaluated. All the target compounds were characterized by 1HNMR, 13CNMR, mass spectra and elemental analysis. The biological evaluation showed that most of the synthesized compounds displayed nanomolar affinity to the angiotensin II type 1 (AT1) receptor and could decrease blood pressure efficiently in spontaneously hypertensive rats. The maximal response of mean blood pressure (MBP) lowered 74.5 ± 3.5 mmHg (1g) and 69.2 ± 0.9 mmHg (2a) at 10 g/kg after oral administration, and the antihypertensive effect lasted beyond 24 h, which performed better than both losartan and telmisartan. So, compounds 1g and 2a may be considered as potential antihypertension drug candidates.
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Anti-Hipertensivos/uso terapêutico , Benzimidazóis/síntese química , Benzimidazóis/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Animais , Anti-Hipertensivos/farmacologia , Desenho de Fármacos , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Chitin, a major component of the fungal cell wall, triggers plant innate immunity in Arabidopsis via a receptor complex including two major lysin motif receptor-like kinases, AtLYK5, and AtCERK1. Although AtLYK5 has been proposed to be a major chitin-binding receptor, the pseudokinase domain of AtLYK5 is required to mediate chitin-triggered immune responses in plants. In this study, 48 AtLYK5-interacting proteins were identified using immunoprecipitation and mass spectrometry assay. Among them, Arabidopsis CALCIUM-DEPENDENT PROTEIN KINASE 5 (AtCPK5) is a protein kinase interacting with both AtLYK5 and AtCERK1. Chitin-induced immune responses are inhibited in both Arabidopsis atcpk5 and atcpk5/6 mutant plants. AtLYK5 and AtLYK4 but not AtCERK1 are phosphorylated by AtCPK5 and AtCPK6 in vitro. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis and in vitro kinase assay identified that Ser-323 and Ser-542 of AtLYK5 are important phosphorylation residues by AtCPK5. Transgenic Arabidopsis expressing either AtLYK5-S323A or AtLYK5-S542A in the atlyk5-2 mutant only partially rescue the defects in chitin-triggered MPK3/MPK6 phosphorylation. Overexpression of AtCPK5 could increase AtCERK1 protein level after chitin treatment. These data proposed a model in which AtCPK5 directly phosphorylates AtLYK5 and regulates chitin-induced defense responses in Arabidopsis.