RESUMEN
The aim of this study was to evaluate the effect of lipid digestion on the permeability and absorption of orally administered saquinavir (SQV), a biopharmaceutics classification system (BCS) class IV drug, in different lipid-based formulations. Three LBFs were prepared: a mixed short- and medium-chain lipid-based formulation (SMCF), a medium-chain lipid-based formulation (MCF), and a long-chain lipid-based formulation (LCF). SQV was loaded into these LBFs at 26.7 mg/g. To evaluate the pharmacokinetics of SQV in vivo, drug-loaded formulations were predispersed in purified water at 3% w/w and orally administered to rats. A low dose (0.8 mg/rat) was employed to limit confounding effects on drug solubilization, and consistent with this design, presolubilization of SQV in the LBFs did not increase in vivo exposure compared to a control suspension formulation. The areas under the plasma concentration-time curve were, however, significantly lower after administration of SQV as MCF and LCF compared to SMCF. To evaluate the key mechanisms underpinning absorption, each LBF containing SQV was digested, and the flux of SQV from the digests across a dialysis membrane was evaluated in in vitro permeation experiments. This study revealed that the absorption profiles were driven by the free concentration of SQV and that this varied due to differences in SQV solubilization in the digestion products generated by LBF digestion. The apparent first-order permeation rate constants of SQV (kapp,total) were estimated by dividing the flux of SQV in the dialysis membrane experiments by the concentration of total SQV on the donor side. kapp,total values strongly correlated with in vivo AUC. The data provide one of the first studies of the effect of digestion products on the free concentration of a drug in the GI fluid and oral absorption. This simple permeation model may be a useful tool for the evaluation of the impact of lipid digestion on apparent drug permeability from lipid-based formulations. These effects should be assessed alongside, and in addition to, the more well-known effects of lipids on enhancing intestinal solubilization of poorly water-soluble drugs.
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Excipientes/química , Lípidos/química , Saquinavir/farmacocinética , Administración Oral , Animales , Área Bajo la Curva , Líquidos Corporales/química , Química Farmacéutica , Absorción Gastrointestinal , Absorción Intestinal , Masculino , Modelos Animales , Permeabilidad , Ratas , Saquinavir/administración & dosificación , Saquinavir/química , SolubilidadRESUMEN
This study investigated the dissolution behavior of BCS class II ionizable weak base Saquinavir and its mesylate salt in the multi-compartment transfer setup employing different composition of dissolution media. The dissolution behavior of Saquinavir was studied by using a two-compartment transfer model representing the transfer of drug from the stomach (donor compartment) to the upper intestine (acceptor compartment). Various buffers like phosphate, bicarbonate, FaSSIF, and FeSSIF were employed. The dissolution was also studied in the concomitant presence of the additional solute, i.e., Quercetin. Further, the dissolution profiles of Saquinavir and its mesylate salt were simulated by GastroPlusTM, and the simulated dissolution profiles were compared against the experimental ones. The formation of in situ HCl salt and water-soluble amorphous phosphate aggregates was confirmed in the donor and acceptor compartments of the transfer setup, respectively. As the consequence of the lower solubility product of HCl salt of Saquinavir, the solubility advantage of mesylate salt was vanished leading to the lower than the predicted dissolution in the acceptor compartment. However, the formation of water-soluble aggregates in the presence of the phosphate salts was observed leading to the higher than the predicted dissolution of the free base in the transfer setup. Interestingly, the formation of such water-soluble aggregates was found to be hindered in the concomitant presence of an ionic solute resulting in the lower dissolution rates. The in situ generation of salts and aggregates in the transfer model lead to the inconsistent prediction of dissolution profiles by GastroPlusTM.
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Inhibidores del Citocromo P-450 CYP3A/química , Saquinavir/química , Administración Oral , Tampones (Química) , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Solubilidad , EstómagoRESUMEN
Garlic has been used as a traditional medicine to treat various diseases. Garlic reduces the risk of some diseases. This protective effect is due to the organosulfur compounds of garlic. The aim of this study was to investigate the inhibition effects of garlic-derived compounds on human immunodeficiency virus type 1 (HIV-1) and as the most important anti-HIV-1 medicine. The activation of saquinavir is believed to be the principal mechanism behind the protective effects of HIV-1. Our theoretical calculations are performed for blood phase by using the density functional theory for the main compounds of garlic. The chemical activity and solubility of ajoene and the mainly derived compounds of garlic as theoretical calculations are important for the medical research comparing with the other compounds of the garlic. The theoretical calculations have helped us to determine which active ingredient of the garlic having inhibition effects on HIV-1 and saquinavir.
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Fármacos Anti-VIH/farmacología , Ajo/química , Inhibidores de la Proteasa del VIH/farmacología , Proteasa del VIH/metabolismo , VIH-1/efectos de los fármacos , Fitoquímicos/farmacología , Saquinavir/antagonistas & inhibidores , Fármacos Anti-VIH/química , Antioxidantes/química , Antioxidantes/farmacología , Dominio Catalítico , Biología Computacional , Teoría Funcional de la Densidad , Disulfuros/química , Disulfuros/farmacología , Interacciones Farmacológicas , Sinergismo Farmacológico , Proteasa del VIH/química , Inhibidores de la Proteasa del VIH/química , VIH-1/enzimología , Simulación del Acoplamiento Molecular , Fitoquímicos/química , Saquinavir/agonistas , Saquinavir/química , Saquinavir/farmacología , Solubilidad , SulfóxidosRESUMEN
FISLE-412 is the first reported small molecule peptidomimetic that neutralizes anti-dsDNA autoantibodies associated with systemic lupus erythematosus (SLE) pathogenesis. FISLE-412 is a complex small molecule that involves a challenging synthesis scheme, but has attractive pharmacological activities as a potential small molecule therapeutic in lupus. Therefore, we initiated a Structure-Activity Relationship study to simplify the complexity of FISLE-412. We synthesized a small library of mimetopes around the FISLE-412 structure and identified several analogues which could neutralize anti-DNA lupus antibodies in vitro and ex vivo. Our strategies reduced the structural complexity of FISLE-412 and provide important information that may guide development of potential autoantibody-targeted lupus therapeutics.
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Anticuerpos Antinucleares/metabolismo , Quinolinas/química , Saquinavir/química , Anticuerpos Antinucleares/química , Diseño de Fármacos , Humanos , Concentración 50 Inhibidora , Riñón/metabolismo , Lupus Eritematoso Sistémico/metabolismo , Lupus Eritematoso Sistémico/patología , Peptidomiméticos , Poliaminas/química , Poliaminas/metabolismo , Quinolinas/metabolismo , Relación Estructura-ActividadRESUMEN
A useful method was developed for the synthesis of active esters by palladium-catalyzed alkoxycarbonylation of (hetero)aromatic bromides. The protocol was general for a range of oxygen nucleophiles including N-hydroxysuccinimide (NHS), pentafluorophenol (PFP), hexafluoroisopropyl alcohol (HFP), 4-nitrophenol, and N-hydroxyphthalimide. A high functional group tolerance was displayed, and several active esters were prepared with good to excellent isolated yields. The protocol was extended to access an important synthetic precursor to the HIV-protease inhibitor, saquinavir, by formation of an NHS ester followed by acyl substitution.
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Bromuros/química , Inhibidores de la Proteasa del VIH/química , Inhibidores de la Proteasa del VIH/síntesis química , Hidrocarburos Halogenados/química , Paladio/química , Ftalimidas/química , Saquinavir/química , Saquinavir/síntesis química , Succinimidas/química , Catálisis , Ésteres , Estructura MolecularRESUMEN
PURPOSE: Intestinal lymphatic transport of specific lipophilic drugs offers therapeutic advantages and maximises oral bioavailability. The aims of this study were; to compare intestinal lymphatic transport of a range of drugs and to investigate the influence of cyclosporine A on the mechanism/extent of lymphatic transport. METHODS: Caco2 cells and an anaesthetised mesenteric lymphatic cannulated rat model were used for in vitro and in vivo studies. Lymphatic transport of three lipophilic drugs was directly compared in a long chain fatty acid formulation. In addition, the impact of cyclosporine A on triglyceride turnover was evaluated in vivo and in vitro. RESULTS: The extent of intestinal lymphatic transport in rats was positively correlated with drug solubility in triglyceride and negatively correlated with drug aqueous solubility. Cyclosporine A displayed non-linear lymphatic transport kinetics and reduced intestinal lymph triglyceride. In vitro experiments indicated that the cellular processes affected were intracellular lipid processing and/or lipid secretion. CONCLUSIONS: The linear correlations obtained using a range of lipophilic drugs confirm that the simplified approach of determining aqueous or triglyceride drug solubility is useful in predicting the extent of lymphatic transport. In vitro experiments correlated with in vivo observations, demonstrating the usefulness of the Caco-2 model for mechanistic investigations.
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Absorción Intestinal , Mucosa Intestinal/metabolismo , Linfa/metabolismo , Animales , Células CACO-2 , Ciclosporina/química , Ciclosporina/farmacocinética , Ciclosporina/farmacología , Inhibidores del Citocromo P-450 CYP3A/química , Inhibidores del Citocromo P-450 CYP3A/farmacocinética , DDT/química , DDT/farmacocinética , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/farmacología , Humanos , Intestinos/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Linfa/efectos de los fármacos , Ratas , Saquinavir/química , Saquinavir/farmacocinética , Solubilidad , Triglicéridos/metabolismoRESUMEN
AIM: Saquinavir (SQV) is the first protease inhibitor for the treatment of HIV infection, but with poor solubility. The aim of this study was to prepare a colloidal nanocrystal suspension for improving the oral absorption of SQV. METHODS: SQV nanocrystals were prepared using anti-solvent precipitation-high pressure homogenization method. The nanocrystals were characterized by a Zetasizer and transmission electron microscopy (TEM). Their dissolution, cellular uptake and transport across the human colorectal adenocarcinoma cell line (Caco-2) monolayer were investigated. Bioimaging of ex vivo intestinal sections of rats was conducted with confocal laser scanning microscopy. Pharmacokinetic analysis was performed in rats administered nanocrystal SQV suspension (50 mg/kg, ig), and the plasma SQV concentrations were measured with HPLC. RESULTS: The SQV nanocrystals were approximately 200 nm in diameter, with a uniform size distribution. The nanocrystals had a rod-like shape under TEM. The dissolution, cellular uptake, and transport across a Caco-2 monolayer of the nanocrystal formulation were significantly improved compared to those of the coarse crystals. The ex vivo intestinal section study revealed that the fluorescently labeled nanocrystals were located in the lamina propria and the epithelium of the duodenum and jejunum. Pharmacokinetic study showed that the maximal plasma concentration (Cmax) was 2.16-fold of that for coarse crystalline SQV suspension, whereas the area under the curve (AUC) of nanocrystal SQV suspension was 1.95-fold of that for coarse crystalline SQV suspension. CONCLUSION: The nanocrystal drug delivery system significantly improves the oral absorption of saquinavir.
Asunto(s)
Inhibidores de la Proteasa del VIH/farmacocinética , Saquinavir/farmacocinética , Administración Oral , Animales , Células CACO-2 , Cristalización/métodos , Inhibidores de la Proteasa del VIH/administración & dosificación , Inhibidores de la Proteasa del VIH/sangre , Inhibidores de la Proteasa del VIH/química , Humanos , Absorción Intestinal , Mucosa Intestinal/metabolismo , Masculino , Nanopartículas/administración & dosificación , Nanopartículas/química , Ratas , Ratas Sprague-Dawley , Saquinavir/administración & dosificación , Saquinavir/sangre , Saquinavir/química , SolubilidadRESUMEN
OBJECTIVE: Saquinavir (SQV) is a US-FDA approved HIV protease inhibitor (HPI) for HIV cure. The purpose of the present investigation was to develop and characterize the anticancer potential of the SQV-loaded folic acid (FA) conjugated PEGylated and non-PEGylated poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles (NPs) (SQV-Fol-PEG-PLGA and SQV-Fol-PLGA) employing PC-3 (human prostate) and MCF-7 (human breast) cancer cell lines. MATERIALS AND METHODS: Developed NPs were characterized by IR, NMR, DSC, XRD, size, charge and further tested for drug loading and cellular uptake properties. RESULT: The entrapment efficiency was found to be 56 ± 0.60 and 58 ± 0.80 w/v for SQV-Fol-PEG-PLGA and SQV-PLGA NPs, respectively. The obtained results of SQV-Fol-PEG-PLGA showed enhanced cytotoxicity and cellular uptake and were most preferentially taken up by the cancerous cells via folate receptor-mediated endocytosis (RME) mechanism. At 260 µM concentration, SQV-PLGA NPs and SQV-Fol-PEG-PLGA NPs showed 20%, 20% and 23% cell growth inhibition in PC-3 cells, respectively whereas in MCF-7 cells it was 12%, 15% and 14% cell growth inhibition, respectively. CONCLUSIONS: Developed targeted SQV-Fol-PEG-PLGA NPs were superior anticancer potential as compared to non-targeted SQV-PLGA NPs. Thus, these targeted NPs provide another option for anticancer drug delivery scientists.
Asunto(s)
Antineoplásicos/administración & dosificación , Ácido Fólico/administración & dosificación , Nanopartículas , Saquinavir/administración & dosificación , Antineoplásicos/química , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Portadores de Fármacos/química , Composición de Medicamentos/métodos , Sistemas de Liberación de Medicamentos , Endocitosis/efectos de los fármacos , Femenino , Ácido Fólico/química , Ácido Fólico/farmacología , Humanos , Ácido Láctico/química , Células MCF-7 , Masculino , Tamaño de la Partícula , Poliésteres/química , Polietilenglicoles/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Saquinavir/química , Saquinavir/farmacologíaRESUMEN
An ionic liquid-based dispersive liquid-liquid microextraction followed by RP-HPLC determination of the most commonly prescribed protease inhibitor, saquinavir, in rat plasma was developed and validated. The effects of different ionic liquids, dispersive solvents, extractant/disperser ratio and salt concentration on sample recovery and enrichment were studied. Among the ionic liquids investigated, 1-butyl-3-methylimidazolium hexafluorophosphate was found to be most effective for extraction of saquinavir from rat serum. The recovery was found to be 95% at an extractant/disperser ratio of 0.43 using 1-butyl-3-methylimidazolium hexafluorophosphate and methanol as extraction and dispersive solvents. The recovery was further enhanced to 99.5% by addition of 5.0% NaCl. A threefold enhancement in detection and quantification limits was achieved, at 0.01 and 0.03 µg/mL, compared with the conventional protein precipitation method. A linear relationship was observed in the range of 0.035-10.0 µg/mL with a correlation coefficient (r(2) ) of 0.9996. The method was validated and applied to study pharmacokinetics of saquinavir in rat serum.
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Cromatografía de Fase Inversa/métodos , Microextracción en Fase Líquida/métodos , Saquinavir/sangre , Saquinavir/aislamiento & purificación , Animales , Cromatografía Líquida de Alta Presión/métodos , Imidazoles/química , Líquidos Iónicos/química , Límite de Detección , Modelos Lineales , Masculino , Metanol/química , Ratas , Ratas Wistar , Reproducibilidad de los Resultados , Saquinavir/química , Saquinavir/farmacocinética , Cloruro de SodioRESUMEN
This study was performed to investigate the impact of pharmaceutical excipients commonly used for lymphatic transport on in vitro drug association with chylomicrons (CM). A CM association study was conducted using saquinavir solubilized in four different pharmaceutical excipients. We observed a linear relationship between saquinavir solubility and drug association, suggesting that the solubility of saquinavir in excipients is a key determinant for successful lymphatic delivery. Broadly, these results suggest that excipients with good solubilization properties may be advantageous for enhancing lymphatic drug delivery.
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Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/química , Quilomicrones/química , Saquinavir/administración & dosificación , Saquinavir/química , Animales , Fármacos Anti-VIH/farmacocinética , Química Farmacéutica , Excipientes , Masculino , Tamaño de la Partícula , Ratas , Ratas Wistar , Saquinavir/farmacocinética , SolubilidadRESUMEN
Acquired immunodeficiency syndrome (AIDS) is one of the most challenging infectious diseases to treat on a global scale. Understanding the mechanisms underlying the development of drug resistance is necessary for novel therapeutics. HIV subtype C is known to harbor mutations at critical positions of HIV aspartic protease compared to HIV subtype B, which affects the binding affinity. Recently, a novel double-insertion mutation at codon 38 (L38HL) was characterized in HIV subtype C protease, whose effects on the interaction with protease inhibitors are hitherto unknown. In this study, the potential of L38HL double-insertion in HIV subtype C protease to induce a drug resistance phenotype towards the protease inhibitor, Saquinavir (SQV), was probed using various computational techniques, such as molecular dynamics simulations, binding free energy calculations, local conformational changes and principal component analysis. The results indicate that the L38HL mutation exhibits an increase in flexibility at the hinge and flap regions with a decrease in the binding affinity of SQV in comparison with wild-type HIV protease C. Further, we observed a wide opening at the binding site in the L38HL variant due to an alteration in flap dynamics, leading to a decrease in interactions with the binding site of the mutant protease. It is supported by an altered direction of motion of flap residues in the L38HL variant compared with the wild-type. These results provide deep insights into understanding the potential drug resistance phenotype in infected individuals.
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Infecciones por VIH , Inhibidores de la Proteasa del VIH , VIH-1 , Humanos , Saquinavir/química , Saquinavir/farmacología , Inhibidores de la Proteasa del VIH/química , Inhibidores de la Proteasa del VIH/farmacología , VIH-1/genética , Proteasa del VIH/genética , Farmacorresistencia Viral/genéticaRESUMEN
Human immunodeficiency virus-1 (HIV-1) protease is one of the important targets in AIDS therapy. The majority of HIV infections are caused due to non-B subtypes in developing countries. The co-occurrence of mutations along with naturally occurring polymorphisms in HIV-1 protease cause resistance to the FDA approved drugs, thereby posing a major challenge in the treatment of antiretroviral therapy. In this work, the resistance mechanism against SQV due to active site mutations G48V and V82F in CRF01_AE (AE) protease was explored. The binding free energy calculations showed that the direct substitution of valine at position 48 introduces a bulkier side chain, directly impairing the interaction with SQV in the binding pocket. Also, the intramolecular hydrogen bonding network of the neighboring residues is altered, indirectly affecting the binding of SQV. Interestingly, the substitution of phenylalanine at position 82 induces conformational changes in the 80's loop and the flap region, thereby favoring the binding of SQV. The V82F mutant structure also maintains similar intramolecular hydrogen bond interactions as observed in AE-WT.Communicated by Ramaswamy H. Sarma.
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Infecciones por VIH , Inhibidores de la Proteasa del VIH , Humanos , Saquinavir/química , Saquinavir/farmacología , Simulación de Dinámica Molecular , Inhibidores de la Proteasa del VIH/química , VIH/metabolismo , Péptido Hidrolasas/metabolismo , Proteasa del VIH/química , Mutación , Resistencia a Medicamentos , Farmacorresistencia Viral/genéticaRESUMEN
We have examined the influence of the nitric oxide (NO)-modified anti-inflammatory drug (S,R)-3-phenyl-4,5-dihydro-5-isoxasole acetic acid (VGX-1027) named GIT-27NO or the NO-modified antiviral drug saquinavir (Saq) named Saq-NO on two colon cancer cell lines, mouse CT26CL25 and human HCT116. The effects of the drugs on cell viability, apoptosis, proliferation, and metastatic potential were analyzed. The release of NO and oxygen and nitrogen species was also determined. The efficacy of the drugs was evaluated in vivo in BALB/c mice injected with CT26CL25 cells. Both agents suppressed the growth of colon cancer cells in vitro and reduced tumor volume in syngeneic BALB/c mice. However, their mechanisms of action were different because GIT-27NO released larger amounts of nitrite than Saq-NO in cell cultures and its antitumor action depended on the intracellular NO release inside the cells. On the contrary, Saq-NO released barely detectable amounts of NO and its antitumor action was NO-independent. In fact, cotreatment with an NO-peroxynitrite scavenger revealed that GIT-27NO but not Saq-NO acts through peroxynitrite-mediated cell destruction. At the cellular level, GIT-27NO prevalently induced proapoptotic signals followed by caspase-dependent apoptosis. In contrast, Saq-NO blocked cell proliferation, changed the adhesive, migratory, and invasive properties of the cells, and decreased metastatic potential in vivo. In conclusion, differences in NO release and oxidative stress generation between GIT-27NO and Saq-NO resulted in different mechanisms that caused cell death.
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Acetatos/farmacología , Antineoplásicos/farmacología , Neoplasias del Colon/tratamiento farmacológico , Óxido Nítrico/química , Oxazoles/farmacología , Saquinavir/farmacología , Acetatos/química , Acetatos/uso terapéutico , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias del Colon/patología , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Metástasis de la Neoplasia , Trasplante de Neoplasias , Óxido Nítrico/fisiología , Oxazoles/química , Oxazoles/uso terapéutico , Saquinavir/química , Saquinavir/uso terapéuticoRESUMEN
PURPOSE: To predict and determine whether the protease inhibitors (PIs) nelfinavir, amprenavir, atazanavir, ritonavir, and saquinavir could serve as metabolic inhibitors of the human CES1 (hCES1) using both molecular modeling techniques and in vitro inhibition assays. METHODS: Initially, a molecular modeling approach was utilized to predict whether the selected PIs could serve as hCES1 inhibitors. The inhibitory effects of these PIs on hCES1 activity were then further evaluated utilizing previously established in vitro assay. RESULTS: Pharmacophore and 2D-QSAR modeling predicted that nelfinavir would serve as a potent hCES1 inhibitor. This hypothesis was validated by in vitro hCES1 inhibition studies. Other PIs (amprenavir, atazanavir, ritonavir, saquinavir) were evaluated and also shown to be hCES1 inhibitors in vitro, although substantially less potent relative to nelfinavir. CONCLUSION: Computational molecular modeling is a valid approach to identify potential hCES1 inhibitors as candidates for further assessment using validated in vitro techniques. DDIs could occur when nelfinavir is co-administered with drugs metabolized by hCES1.
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Antivirales/farmacología , Hidrolasas de Éster Carboxílico/antagonistas & inhibidores , Inhibidores de Proteasas/farmacología , Antivirales/química , Sulfato de Atazanavir , Carbamatos/química , Carbamatos/farmacología , Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/metabolismo , Interacciones Farmacológicas , Furanos , Humanos , Cinética , Modelos Moleculares , Nelfinavir/química , Nelfinavir/farmacología , Oligopéptidos/química , Oligopéptidos/farmacología , Inhibidores de Proteasas/química , Piridinas/química , Piridinas/farmacología , Relación Estructura-Actividad Cuantitativa , Ritonavir/química , Ritonavir/farmacología , Saquinavir/química , Saquinavir/farmacología , Sulfonamidas/química , Sulfonamidas/farmacologíaRESUMEN
HYPOTHESIS: The aim of this study was the development of nanostructured lipid carriers (NLCs) decorated with a polycationic cell-penetrating peptide (CPP). A coating with polyphosphates (PP) enables charge conversion at target cells being triggered by the membrane bound enzyme intestinal alkaline phosphatase (IAP). EXPERIMENTS: The CPP, stearyl-nona-L-arginine (R9SA) was obtained by solid phase synthesis. Formed nanocarriers were characterized regarding size, polydispersity index, zeta potential and charge conversion in the presence of IAP and on Caco-2 cells. The BCS class IV drug saquinavir (SQV) was loaded into NLCs in different concentrations. Mucus diffusion ability of the NLCs was evaluated by the rotating tube method. Furthermore, cellular uptake was evaluated on Caco-2 cells and endosomal escape properties were investigated using erythrocytes. FINDINGS: All NLCs were obtained in a size range between 146 nm and 152 nm and a polydispersity index of 0.2. Incubation of PP coated PP-R9SA-NLCs with IAP led to a charge conversion from -41.8 mV to 6.4 mV (Δ48.2 mV). After four hours of incubation with IAP, phosphate release reached a plateau, indicating a faster polyphosphate cleavage than on Caco-2. Drug load and encapsulation efficiency of SQV was obtained up to 80.6% and 46.5 µg/mg. Mucus diffusion was increasing in the following rank order: R9SA-NLCs < blank NLCs < PP-R9SA-NLCs. R9SA-NLCs and PP-R9SA-NLCs increased the cellular uptake 15.6- and 13.2-fold, respectively, compared to the control NLCs. Erythrocytes interaction study revealed enhanced endosomal escape properties for R9SA-NLCs and PP-R9SA-NLCs when incubated with IAP.
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Péptidos de Penetración Celular , Nanoestructuras , Fosfatasa Alcalina , Células CACO-2 , Portadores de Fármacos/química , Humanos , Lípidos/química , Nanoestructuras/química , Tamaño de la Partícula , Polifosfatos , Saquinavir/químicaRESUMEN
There is a need of computational tools to rank bRo5 drug candidates in the very early phases of drug discovery when chemical matter is unavailable. In this study, we selected three compounds: (a) a Ro5 drug (Pomalidomide), (b) a bRo5 orally available drug (Saquinavir), and (c) a polar PROTAC (CMP 98) to focus on computational access to physicochemical properties. To provide a benchmark, the three compounds were first experimentally characterized for their lipophilicity, polarity, IMHBs, and chameleonicity. To reproduce the experimental information content, we generated conformer ensembles with conformational sampling and molecular dynamics in both water and nonpolar solvents. Then we calculated Rgyr, 3D PSA, and IMHB number. An innovative pool of strategies for data analysis was then provided. Overall, we report a contribution to close the gap between experimental and computational methods for characterizing bRo5 physicochemical properties.
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Química Computacional , Descubrimiento de Drogas , Saquinavir , Química Computacional/métodos , Descubrimiento de Drogas/métodos , Simulación de Dinámica Molecular , Saquinavir/química , Solventes , Talidomida/análogos & derivados , Talidomida/química , AguaRESUMEN
Developing novel drug molecules against HIV is a scientific quest necessitated by development of drug resistance against used drugs. We report comparative results of molecular dynamics simulation studies on 11 structural analogues of Saquinavir (SQV) - against HIV-protease that were earlier examined for pharmacodynamic and pharmacokinetic properties. We reported analogues S1, S5 and S8 to qualify the ADMET criterion and may be considered as potential lead molecules. In this study the designed molecules were successively docked with native HIV-protease at AutoDock. Docking scores established relative goodness of the 11 analogues against the benchmark for Saquinavir. The docked complexes were subjected to molecular dynamics simulation studies using GROMACS 4.6.2. Four parameters viz. H-bonding, RMSD, Binding energy and Protein-Ligand Distance were used for comparative analyses of the analogues relative to Saquinavir. The comparison and analysis of the results are indicative that analogues S8, S9 and S1 are promising candidates among all the analogues studied. From our earlier work and present study it is evident that among the three S8 and S1 qualify the ADMET criterion and between S1 and S8, the analogue S8 shows more target efficacy and specificity over S1 and have better molecular dynamics simulation results. Thus, of the 11 de novo Saquinavir analogues, the S8 appears to be the most promising candidate as lead molecule for HIV-protease inhibitor and is best suited for testing under biological system. Further validation of the proposed lead molecules through wet lab studies involving antiviral assays however is required.Communicated by Ramaswamy H. Sarma.
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Infecciones por VIH , Inhibidores de la Proteasa del VIH , Infecciones por VIH/tratamiento farmacológico , Proteasa del VIH/química , Inhibidores de la Proteasa del VIH/química , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Saquinavir/química , Saquinavir/metabolismo , Saquinavir/farmacologíaRESUMEN
Drug-resistance-associated mutation in essential proteins of the viral life cycle is a major concern in anti-retroviral therapy. M46I, a non-active site mutation in HIV-1 protease has been clinically associated with saquinavir resistance in HIV patients. A 100 ns molecular dynamics (MD) simulation and MM-PBSA calculations were performed to study the molecular mechanism of M46I-mutation-based saquinavir resistance. In order to acquire deeper insight into the drug-resistance mechanism, the flap curling, closed/semi-open/open conformations, and active site compactness were studied. The M46I mutation significantly affects the energetics and conformational stability of HIV-1 protease in terms of RMSD, RMSF, Rg, SASA, and hydrogen formation potential. This mutation significantly decreased van der Waals interaction and binding free energy (∆G) in the M46I-saquinavir complex and induced inward flap curling and a wider opening of the flaps for most of the MD simulation period. The predominant open conformation was reduced, but inward flap curling/active site compactness was increased in the presence of saquinavir in M46I HIV-1 protease. In conclusion, the M46I mutation induced structural dynamics changes that weaken the protease grip on saquinavir without distorting the active site of the protein. The produced information may be utilized for the discovery of inhibitor(s) against drug-resistant HIV-1 protease.
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Infecciones por VIH , Inhibidores de la Proteasa del VIH , VIH-1 , Sitios de Unión , Dominio Catalítico , Farmacorresistencia Viral/genética , Infecciones por VIH/tratamiento farmacológico , Proteasa del VIH/metabolismo , Inhibidores de la Proteasa del VIH/química , Inhibidores de la Proteasa del VIH/farmacología , VIH-1/genética , VIH-1/metabolismo , Humanos , Simulación de Dinámica Molecular , Mutación , Saquinavir/química , Saquinavir/metabolismo , Saquinavir/farmacologíaRESUMEN
AIMS: To predict potential drugs for COVID-19 by using molecular docking for virtual screening of drugs approved for other clinical applications. BACKGROUND: SARS-CoV-2 is the betacoronavirus responsible for the COVID-19 pandemic. It was listed as a potential global health threat by the WHO due to high mortality, high basic reproduction number, and lack of clinically approved drugs and vaccines. The genome of the virus responsible for COVID-19 has been sequenced. In addition, the three-dimensional structure of the main protease has been determined experimentally. OBJECTIVE: To identify potential drugs that can be repurposed for treatment of COVID-19 by using molecular docking based virtual screening of all approved drugs. METHODS: A list of drugs approved for clinical use was obtained from the SuperDRUG2 database. The structure of the target in the apo form, as well as structures of several target-ligand complexes, were obtained from RCSB PDB. The structure of SARS-CoV-2 Mpro determined from X-ray diffraction data was used as the target. Data regarding drugs in clinical trials for COVID-19 was obtained from clinicaltrials.org. Input for molecular docking based virtual screening was prepared by using Obabel and customized python, bash, and awk scripts. Molecular docking calculations were carried out with Vina and SMINA, and the docked conformations were analyzed and visualized with PLIP, Pymol, and Rasmol. RESULTS: Among the drugs that are being tested in clinical trials for COVID-19, Danoprevir and Darunavir were predicted to have the highest binding affinity for the Main protease (Mpro) target of SARS-CoV-2. Saquinavir and Beclabuvir were identified as the best novel candidates for COVID-19 therapy by using Virtual Screening of drugs approved for other clinical indications. CONCLUSION: Protease inhibitors approved for treatment of other viral diseases have the potential to be repurposed for treatment of COVID-19.
Asunto(s)
Antivirales/farmacología , Tratamiento Farmacológico de COVID-19 , COVID-19/virología , Evaluación Preclínica de Medicamentos , Simulación del Acoplamiento Molecular , SARS-CoV-2/efectos de los fármacos , Antivirales/química , Benzazepinas/química , Benzazepinas/farmacología , Ciclopropanos/química , Ciclopropanos/farmacología , Darunavir/química , Darunavir/farmacología , Reposicionamiento de Medicamentos , Ensayos Analíticos de Alto Rendimiento , Humanos , Indoles/química , Indoles/farmacología , Isoindoles/química , Isoindoles/farmacología , Lactamas Macrocíclicas/química , Lactamas Macrocíclicas/farmacología , Prolina/análogos & derivados , Prolina/química , Prolina/farmacología , Saquinavir/química , Saquinavir/farmacología , Sulfonamidas/química , Sulfonamidas/farmacologíaRESUMEN
The mutation G48V in HIV-1 protease is a major resistance mutation against the drug saquinavir. Recently, G48V mutation is found to co-exist with the mutation C95F in AIDS patients treated with saquinavir. We report here the three-dimensional crystal structure of G48V/C95F tethered HIV-1 protease/saquinavir complex. The structure indicates following as the possible causes of drug resistance: (1) loss of direct van der Waals interactions between saquinavir and enzyme residues PHE-53 and PRO-1081, (2) loss of water-mediated hydrogen bonds between the carbonyl oxygen atoms in saquinavir and amide nitrogen atoms of flap residues 50 and 1050, (3) changes in inter-monomer interactions, which could affect the energetics of domain movements associated with inhibitor-binding, and (4) significant reduction in the stability of the mutant dimer. The present structure also provides a rationale for the clinical observation that the resistance mutations C95F/G48V/V82A occur as a cluster in AIDS patients.