RESUMO
Doxepin, a Class-I Biopharmaceutics Drug Disposition Classification System (BDDCS) drug, exhibits poor bioavailability due to extensive first-pass metabolism. This research focuses on enhancing the delivery of doxepin by formulating nanostructured lipid carriers (NLCs) through the utilization of the Box-Behnken Design methodology. These optimized NLCs are intended for intranasal administration, with the ultimate goal of improving nose-to-brain drug delivery. NLCs were formulated using a high-speed homogenization technique. The optimized batch had a small particle size (75.80 ± 5.48 nm, PDI = 0.286), high entrapment efficiency (94.10 ± 0.16%), and sustained ex vivo release (82.25 ± 4.61% at 24 h). Characterization studies confirmed the conversion of doxepin from a crystalline to an amorphous state with uniform distribution in the lipid matrix. In vivo pharmacokinetic studies in rats showed significantly higher doxepin concentration in the brain tissue (Cmax = 16.77 µg/g, tmax = 30 min) after intranasal administration compared to intravenous administration (Cmax = 2.53 µg/g, tmax = 6 h). High-drug targeting efficiency (DTE = 284.3%) and direct transport percentage (DTP = 64.8%) suggested direct penetration of NLCs in the brain via olfactory and trigeminal pathways. In conclusion, the study highlights the potential of NLCs to improve the bioavailability of doxepin through nose-to-brain delivery and thereby potentially enable the treatment of neurological disorders.
Assuntos
Administração Intranasal , Disponibilidade Biológica , Encéfalo , Doxepina , Portadores de Fármacos , Lipídeos , Nanoestruturas , Animais , Doxepina/farmacocinética , Doxepina/administração & dosagem , Encéfalo/metabolismo , Lipídeos/química , Portadores de Fármacos/química , Ratos , Masculino , Nanoestruturas/química , Tamanho da Partícula , Sistemas de Liberação de Medicamentos/métodos , Ratos Sprague-Dawley , Liberação Controlada de Fármacos , Biofarmácia/métodos , Mucosa Nasal/metabolismoRESUMO
The anti-diabetic glipizide (GLN) drug has notable pharmaceutical advantages, but poor aqueous solubility restricts its wide applications. The present work was to develop a mixed polymeric micelle system composed of SA-F127 and TPGS to improve the water solubility and effective delivery of the GLN. First, we synthesized SA-F127 and confirmed it through FTIR, NMR, and GPC techniques. The GLN-PMM were fabricated with the thin-film technique and optimized with CCD design. The developed GLN-PMM was characterized using DLS, Zeta, TEM, Rheology, FTIR, DSC, and XRD measurements. The GLN-PMM manifested a spherical morphology with 67.86 nm particle size, a -3.85 mV zeta potential, and a 0.582±0.06 PDI value. The polymeric mixed micelles showed excellent compatibility with GLN and were amorphous in nature. NMR studies confirmed the encapsulation of GLN in the core of the mixed micelle. In addition, the GLN-PMM micelles were tested in vitro for cumulative drug release, ex vivo for permeation, and in vivo for anti-diabetic investigations. The GLN-PMM release profile in the various pH environments showed over 90% after 24 h, clearly indicating sustained release. The GLN-PMM micelles gave higher 88.86±3.39% GLN permeation from the goat intestine compared with free GLN. In-vivo anti-diabetic investigation proves the powerful anti-diabetic properties of GLN-PMM in comparison to the marketed formulation. These findings demonstrated that the polymeric mixed micelles of SA-F127 and TPGS could be a promising, effective, and environment-friendly approach for oral delivery of the GLN.
Assuntos
Sistemas de Liberação de Medicamentos , Micelas , Sistemas de Liberação de Medicamentos/métodos , Glipizida , Polímeros/química , Portadores de Fármacos/química , Tamanho da Partícula , Poloxâmero/químicaRESUMO
BACKGROUND: Long-term use of proton pump inhibitors (PPIs) has been linked to an increased risk of osteoporosis, with various indirect mechanisms so far identified. Although no direct underlying mechanism for effect on bone cells have been investigated with the use of PPIs. Melastatin-like transient receptor potential 7 (TRPM7)channel has been engaged in the proliferation of bone cells. TRPM7 channel is regulated by extracellular Mg2+ and Ca2+ level, that further encourages to analyse if any imbalance with pantoprazole usage could alter bone remodelling process mediated by TRPM7. OBJECTIVES: The present study was conducted to investigate the effect of pantoprazole on the calcium and magnesium level, the cations involved in the bone remodelling process, as well as role of the TRPM7 channel in the proliferation of bone cells. METHODS: A cytotoxicity study was carried out to study the effect of pantoprazole on the bone cell using MC3T3-E1 cell line, together with the expression of TRPM7 was determined post-pantoprazole treatment. An in vivo study in rats was carried out for estimation of Ca2+, Mg2+ and Ca2+/Mg2+ ratio as well as bone strength was measured over a duration of 4 weeks and 8 weeks with the treatment of pantoprazole. A pilot-scale clinical study was carried out in patients with a fracture to support the evidence of preliminary findings from in-vitro and in vivo studies. RESULTS: MC3T3-E1 cell line treated with pantoprazole showed decreased cell viability in a dose-dependent manner and reduced expression of TRPM7 channel, evidencing interaction of TRPM7 and pantoprazole in the bone remodelling process. A pilot study conducted on 12 patients having major fractures showed changes in serum Mg2+ and Ca2+ levels over a period of 1 month as well as the animal study also showed ionic imbalance over 8-week treatment with pantoprazole. Bone density measured for the patient at the end of the 1-month treatment was found to be in the osteopenic category, together with the animal study which showed a decrease in femur bone strength for the animal treated with pantoprazole over a period of 8 weeks. CONCLUSION: The study findings proved a negative impact of pantoprazole use on Ca2+ and Mg2+ levels, which can impact TRPM7-mediated bone remodelling which serves to be a possible mechanism for osteoporosis upon pantoprazole use.
Assuntos
Osso e Ossos/efeitos dos fármacos , Pantoprazol/farmacologia , Inibidores da Bomba de Prótons/farmacologia , Canais de Cátion TRPM/efeitos dos fármacos , Animais , Densidade Óssea , Cálcio/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Magnésio/metabolismo , Masculino , Pantoprazol/administração & dosagem , Projetos Piloto , Estudos Prospectivos , Inibidores da Bomba de Prótons/administração & dosagem , Ratos , Ratos WistarRESUMO
Clozapine, which is widely used to treat schizophrenia, shows low bioavailability due to poor solubility and high first-pass metabolism. The study aimed to design clozapine-loaded carbon dots (CDs) to enhance availability of the clozapine to the brain via intranasal pathway. The CDs were synthesized by pyrolysis of citric acid and urea at 200⯰C by hydrothermal technique and characterized by photoluminescence, transmission electron microscopy (TEM), X-ray Photoelectron Spectrometer (XPS), and Fourier transform infrared spectrum (FTIR). The optimized clozapine-loaded CDs (CLZ-CDs-1:3-200) showed a quasi-spherical shape (9-12â¯nm) with stable blue fluorescence. The CDs showed high drug solubilization capacity (1.5â¯mg drug in 1â¯mg/ml CDs) with strong electrostatic interaction with clozapine (drug loading efficiency = 94.74%). The ex vivo release study performed using nasal goat mucosa showed sustained release of clozapine (43.89%) from CLZ-CDs-1:3-200 for 30â¯h. The ciliotoxicity study (histopathology) confirmed no toxicity to the nasal mucosal tissues using CDs. In the rat model (in vivo pharmacokinetic study), when CDs were administrated by the intranasal route, a significantly higher concentration of clozapine in the brain tissue (Cmax = 58.07 ± 5.36⯵g/g and AUCt (µg/h*g) = 105.76 ± 12.31) was noted within a short time (tmax = 1â¯h) compared to clozapine suspension administered by intravenous route (Cmax = 20.99 ± 3.91⯵g/g, AUC t (µg/h*g) = 56.89 ± 12.31, and tmax = 4â¯h). The high value of drug targeting efficiency (DTE, 486%) index and direct transport percentage (DTP, 58%) indicates the direct entry of clozapine-CDs in the brain via the olfactory route. In conclusion, designed CDs demonstrated a promising dosage form for targeted nose-to-brain delivery of clozapine for the effective treatment of schizophrenia.
Assuntos
Clozapina , Pontos Quânticos , Ratos , Animais , Carbono/farmacologia , Administração Intranasal , Encéfalo/metabolismo , Mucosa Nasal/metabolismoRESUMO
BACKGROUND: Poor dissolution of Etodolac is one of the major challenges in achieving the desired therapeutic effect in oral therapy. OBJECTIVE: This study aimed to assess the potential of the liquisolid compact technique in increasing the rate of dissolution of Etodolac and thus its bioavailability. METHODS: Liquisolid compacts were prepared using PEG 400, Avicel PH-200 and Aerosil 200 as non-volatile liquid, carrier and coating material, respectively. The optimisation was carried out by applying a 32 full factorial design using Design expert software 11.0.3.0 to examine the effects of independent variables (load factor and carrier: coating ratio) on dependent variables (angle of repose and % cumulative drug release at 30 min [Q 30 min]). Assessment of bioavailability was based on a pharmacokinetic study on rabbits and pharmacodynamics evaluation on rats, respectively. RESULTS: The formulation M3 was identified as the optimised formulation based on the better flow (lower angle of repose) and a higher rate of dissolution (Q 30 min >95%). The higher dissolution rate could be due to conversion of Etodolac into an amorphous molecularly dispersed state, availability of larger surface area, enhancement of aqueous solubility and enhanced wetting of drug particles. Studies with DSC, XRD, and SEM verified the transformation of Etodolac from crystalline to amorphous state, a key factor responsible for improving the dissolution rate. The pharmacokinetic profile of M3 was prominent, demonstrating higher absorption of Etodolac in comparison to oral suspension and immediate-release conventional tablets in rabbits. Liquisolid formulation exhibited a 27% increment in paw thickness as compared to 57% and 46% increments for oral suspension and immediate-release conventional tablets, respectively, after 7 hrs in the carrageenan-induced paw model in rats. CONCLUSION: The results indicated the liquisolid compact technique to be a promising strategy to enhance the bioavailability of Etodolac.
Assuntos
Química Farmacêutica , Etodolac , Administração Oral , Animais , Disponibilidade Biológica , Etodolac/farmacocinética , Coelhos , Ratos , Solubilidade , ComprimidosRESUMO
Clozapine is widely used to treat schizophrenia as an atypical antipsychotic. Low solubility, poor dissolution rate, degradation in the gastrointestinal tract, high hepatic first-pass metabolism, and eventually less drug transfer in the brain are all issues with oral clozapine administration. On account of this poor pharmacokinetic parameters, the authors aimed to develop clozapine nanosuspension using (+)-alpha-tocopherol polyethylene glycol 1000 succinate (TPGS) and polyvinylpyrrolidone K-30 (PVP K-30) and deliver it through the intranasal route. The nanosuspension was prepared by the high-speed homogenization method with 32 full factorial design for optimization of the product. Quality Target Product Profile (QTPP) was enlisted before the product development. The amount of TPGS and speed of homogenizer were selected as independent variables whereas, particle size and drug permeation profile after 24 h (Y2, %) were selected as dependent variables. As per the results of optimization, amount of TPGS and speed of homogenizer were chosen as 0.1% and 7000 rpm, respectively. The particle size of the optimized nanosuspension of clozapine was found to be 281 nm. The conversion of clozapine crystals to an amorphous form was verified by characterization studies (XRD and DSC). The drug permeability study showed 96.15% and 41.12% clozapine release after 24 h from nanosuspension and conventional suspension, respectively. The study of nasal cilio-toxicity (histopathological studies) demonstrated the appropriateness of nanosuspension for intranasal purposes. The single-dose in vivo pharmacokinetic analysis in the rat model showed a substantial increase in the therapeutic concentration of clozapine in the brain tissue in the case of intranasal nanosuspension (dose = 0.05 mg drug/0.1 mL, Cmax = 8.62 ± 0.45 µg/g, tmax = 1 h) compared to conventional oral clozapine suspension (dose = 26.43 mg drug/0.158 mL, Cmax = 1.14 ± 0.12 µg/g, tmax = 1 h).Ultimately, in the case of an intranasal route, a 3.56-fold increase in brain drug concentration was observed with a 528-fold lower drug dose compared with oral administration. The results suggest that clozapine nanosuspension may be used for successful nose-to-brain delivery.
Assuntos
Clozapina , Nanopartículas , Animais , Disponibilidade Biológica , Encéfalo , Tamanho da Partícula , Polietilenoglicóis , Ratos , Solubilidade , Succinatos , Suspensões , alfa-TocoferolRESUMO
PURPOSE: Iloperidone, second generation antipsychotic drug, reported in clinical trial to produce orthostatic hypotension as side effect. It was claimed to be antagonistic at alpha adrenergic receptor in central nervous system. We evaluated effect of Iloperidone on peripheral alpha 1 adrenoreceptor by in silico and in vitro methods while in vivo hypotensive, antihypertensive and ocular hypotensive activity was evaluated in animals. METHODS: Pharmacological activity prediction of Iloperidone was done using PASSOnline and SwissTargetPrediction softwares and molecular docking with Alpha 1A adrenoreceptor using AutoDock Vina. Hypotensive activity in normotensive and antihypertensive activity against DOCA-salt induced hypertension in rats were evaluated at doses 0.03 mg/Kg and 0.1 mg/Kg, i.p of Iloperidone. Blood pressure was measured by invasive blood pressure measurement technique using PowerLab 4/30 and intraocular pressure was measured using digital tonometer. RESULTS: Iloperidone (0.1 mg/Kg) showed significant decrease in blood pressure (38.96 ± 1.1%) in normotensive rats, while in DOCA salt induced hypertensive rats, systolic blood pressure was found to be decreased by 29.04 ± 1.45% and 31.43 ± 1.21% in 0.03 mg/Kg and 0.1 mg/Kg treated rats respectively. Iloperidone prevented rise in systolic BP with adrenaline. Intraocular pressure was found to be decreased by 36.66 ± 3.15% in rabbits after 1 h of instillation of 0.1% Iloperidone. CONCLUSION: Iloperidone exerted hypotensive and/or anti-hypertensive activity in rats and ocular hypotensive activity in rabbits.
Assuntos
Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Isoxazóis/uso terapêutico , Piperidinas/uso terapêutico , Animais , Anti-Hipertensivos/farmacologia , Antipsicóticos/farmacologia , Antipsicóticos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Acetato de Desoxicorticosterona , Reposicionamento de Medicamentos , Feminino , Hipertensão/induzido quimicamente , Hipertensão/fisiopatologia , Pressão Intraocular/efeitos dos fármacos , Isoxazóis/farmacologia , Masculino , Simulação de Acoplamento Molecular , Piperidinas/farmacologia , Ratos Wistar , Receptores Adrenérgicos alfa 1/metabolismo , Teste de Desempenho do Rota-RodRESUMO
A fixed combination of bimatoprost/timolol eye drop solution is used to manage the elevated intra-ocular pressure in glaucoma patients, including individuals whose condition is poorly controlled by monotherapy. Eye drop solutions are generally given in high dose, due to poor ocular bioavailability. The high ocular dose of bimatoprost and timolol lead to hyperaemia and systemic cardiac side effects respectively. Here, we introduce multiple implant-laden contact lenses (IM) to passively deliver timolol, bimatoprost and hyaluronic acid at therapeutically relevant doses without high burst release. The drug-loaded implants were individually implanted in the outer periphery of the silicone contact lenses. Atomic force microscopy showed the smooth surface of the implant contact lens, as the implants were inside the contact lens matrix. The implant lens (IM) showed major loss of drugs [timolol = 60.60%, bimatoprost = 61.75% and HA = 46.03%] during the monomer extraction and wet sterilization, while the option of dry radiation sterilization (IM-R lens) and hydration for 24 h prior to use showed relatively lower loss of drugs [timolol = 16.87%, bimatoprost = 47.95% and HA = 24.41%]. The in-vitro drugs release data of IM-R lens, showed sustained release for 72 h, with low burst release in comparison to the soaked (SM) and direct drug-laden contact lenses (DL). The in vivo drug release data in the rabbit tear fluid showed sustained release using IM-R lens in comparison to the SM lens and eye drop therapy. The burst release with the IM-R lens was many folds reduced, which could bypass the side effects associated with multiple eye drop therapy. The in vivo pharmacodynamic study in the rabbit model showed peak and valley profile with multiple eye drop therapy, while IM-R lens showed prolong reduction in intra ocular pressure (IOP) for 120 h. The study demonstrates the application of implantation technology to deliver multiple drug through contact lenses to treat glaucoma.
Assuntos
Bimatoprost/metabolismo , Lentes de Contato , Portadores de Fármacos/química , Silicones/química , Timolol/metabolismo , Animais , Bimatoprost/administração & dosagem , Bimatoprost/química , Implantes de Medicamento/química , Liberação Controlada de Fármacos , Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/química , Ácido Hialurônico/metabolismo , Pressão Intraocular , Coelhos , Propriedades de Superfície , Timolol/administração & dosagem , Timolol/químicaRESUMO
Contact lenses are ideally suited for extended drug delivery to the ocular tissues, but incorporation of any particulate system affects the critical properties of the contact lens. Timolol loading by the conventional soaking method does not significantly alter the critical properties of the contact lens. However, there are challenges of low drug loading and high burst release. This research work aimed to investigate the effect of gold nanoparticles (GNPs) on loading and its release kinetics from the contact lens using the soaking method. In one approach, GNPs were loaded into the timolol soaking solution (GNPs-SS), and in another approach, GNPs were incorporated into the contact lenses (GNPs-CL) during fabrication. The contact lenses were soaked at two different concentrations of timolol (i.e., 2â¯mg/ml and 4â¯mg/ml). Swelling and optical transmittance were not significantly affected by the presence of GNPs in the contact lenses. A significant uptake/loading of timolol using the GNPs in both the approaches was observed. The in vitro flux data showed no significant improvement in the release rate profiles of timolol when using both approaches. However, the in vivo study in the rabbit tear fluid showed high timolol concentration with the GNPs-laden contact lens at all timepoints in comparison to the soaked contact lenses without GNPs. The in vivo pharmacodynamic study in rabbits showed a 2â¯mmHg average fall in intraocular pressure (72â¯h) using the GNPs-laden contact lenses, while the soaked contact lenses without GNPs and eye drops solution (0.5 %w/v) showed 2â¯mmHg. The drug distribution study in the ocular tissue showed a significant improvement in the drug deposition with the GNPs-laden contact lenses in the ciliary muscle and conjunctiva. This study successfully demonstrated the potential of GNPs to enhance the uptake of drug from the drug soaking solution to treat glaucoma without compromising the critical properties of contact lens. STATEMENT OF SIGNIFICANCE: In this study, we have overcome the limitation of the conventional soaking method of low drug loading and high burst release from the contact lenses. We have investigated the effect of gold nanoparticles (GNPs) on the timolol loading and its release kinetics from the contact lenses. The study revealed the potential of GNPs to enhance the uptake of timolol from the timolol soaking solution to treat glaucoma without compromising the critical lens properties.
Assuntos
Lentes de Contato , Liberação Controlada de Fármacos , Ouro/química , Nanopartículas Metálicas/química , Timolol/farmacologia , Animais , Olho/efeitos dos fármacos , Olho/metabolismo , Pressão Intraocular/efeitos dos fármacos , Cinética , Nanopartículas Metálicas/ultraestrutura , Coelhos , Distribuição Tecidual/efeitos dos fármacosRESUMO
Currently, bacterial conjunctivitis is treated by frequent administration of antibiotic eye drop solutions, which is tedious and patient noncompliant. Contact lenses could be ideal medical devices to sustain the release of ophthalmic drugs, but the incorporation of the latter can alter the optical and physical properties of the lenses. In addition, many contact lens users have reported the pink eye syndrome, making them unsuitable as ocular medical devices. In the present study, we have designed a novel type of lenses containing semi-circular rings loaded with moxifloxacin HCl (a broad spectrum antibiotic) and hyaluronic acid (a comfort agent), respectively, in order to treat bacterial conjunctivitis without altering the critical lens properties. The drug loaded rings were implanted separately within the periphery of the contact lenses using the modified cast moulding technology. The atomic force microscopy report showed an average roughness of 22.27â¯nm for the implant lens, which was significantly lower in comparison to the marketed Freshlook® (116.27â¯nm) contact lens. The major amount of moxifloxacin HCl was leached (68.16-74.55%) during the monomer extraction and wet sterilization (autoclave) steps; hence the lenses were terminally sterilized by radiation and packaged under dry condition (dehydrated). The in vitro release data showed release for moxifloxacin HCl and hyaluronic acid up to 96â¯h. The in vivo drug release studies showed significant improvement [>MIC for Staphylococcus aureus] in the drug residence time in comparison to the eye drop therapy. The in vivo efficacy study in the staphylococcus aureus induced conjunctivitis showed equivalent healing effect with the single implant contact lens in comparison to the frequent high dose eye drop therapy. The study demonstrated the successful application of the implantation technology to co-deliver moxifloxacin HCl and hyaluronic acid from the contact lenses for the extended period of time to treat conjunctivitis.
Assuntos
Antibacterianos/administração & dosagem , Conjuntivite Bacteriana/tratamento farmacológico , Lentes de Contato , Sistemas de Liberação de Medicamentos , Fluoroquinolonas/administração & dosagem , Ácido Hialurônico/administração & dosagem , Animais , Antibacterianos/química , Liberação Controlada de Fármacos , Feminino , Fluoroquinolonas/química , Ácido Hialurônico/química , Masculino , Moxifloxacina , Coelhos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
Glaucoma is a chronic disease, which is currently treated using frequent high dose applications of an eye drop solution; this method is tedious, and most of patients are non-compliant to it. Contact lenses are emerging as a convenient option to sustain the release of ophthalmic drugs. However, the incorporation of a drug/formulation changes the optical and physical properties of contact lenses. Contact lens users have also reported pink eye syndrome; this makes contact lenses unsuitable to be accepted as a medical device. The objective of the present study was to design novel timolol and hyaluronic acid (comfort agent)-loaded semi-circular ring-implanted contact lenses that could uphold the release at therapeutic rates without compromising the critical lens properties. The drug-loaded rings were individually implanted within the periphery of the contact lenses using modified cast-moulding technology. Atomic force microscopy showed an average roughness of 12.38 nm for the implanted lens that was significantly lower as compared to that of the Freshlook contact lenses (116.27 nm). A major amount of timolol was leached (from 46.47 to 58.79%) during the monomer extraction and moist sterilization (autoclave) steps; therefore, the lenses were sterilized by radiation and packaged under dry conditions (dehydrated). The in vitro release data showed sustained release of timolol and hyaluronic acid up to 96 h. The in vivo drug release study on rabbit eyes showed the presence of timolol in tear fluid up to 72 h. The in vivo pharmacodynamics studies showed a reduction in IOP till 144 h with a low drug loading (154 µg) as compared to the case of a single instillation eye drop solution (250 µg). This study has demonstrated the successful application of implantation technology to co-deliver timolol and hyaluronic acid from contact lenses for an extended period of time to treat glaucoma.
Assuntos
Anti-Hipertensivos/administração & dosagem , Lentes de Contato , Sistemas de Liberação de Medicamentos/instrumentação , Glaucoma/tratamento farmacológico , Ácido Hialurônico/administração & dosagem , Timolol/administração & dosagem , Animais , Anti-Hipertensivos/farmacocinética , Liberação Controlada de Fármacos , Desenho de Equipamento , Ácido Hialurônico/farmacocinética , Ácido Hialurônico/uso terapêutico , Coelhos , Timolol/farmacocinética , Timolol/uso terapêuticoRESUMO
In the present work a novel cyclosporine-loaded Eudragit S100 (pH-sensitive) nanoparticles-laden contact lenses were designed to provide sustained release of cyclosporine at therapeutic rates, without leaching of drug during sterilization and storage period (shelf life). The nanoparticles were prepared by Quasi-emulsion solvent diffusion technique using different weight ratios of cyclosporine to Eudragit S100. The contact lenses with direct drug entrapment were also fabricated (DL-50) for comparison. The percentage swelling and optical transparency of nanoparticles-laden contact lenses were improved in comparison to DL-50 lenses. The nanoparticles-laden contact lenses showed sustained drug release profiles, with inverse relationship to the amount of nanoparticles loaded in the contact lenses. It was interesting to note that nanoparticles form nanochannels/cavities after dissolution of Eudragit S 100 in tear fluid pH=7.4 (in vitro release study). This followed the precipitation of drug in hydrogel matrix of contact lenses. As the amount of nanoparticles loading increased, more number of cavities were formed, which caused the formation of large cavities in contact lens matrix. This in turn precipitated the drug. The nanoparticles-laden contact lenses with 1:1 (drug: Eudragit) weight ratio showed the most promising results of sustaining the drug release up to 156h, without affecting optical and physical properties of contact lenses. Packaging study confirmed that the drug was not leached in packaging solution (buffer, pH=6.5) from nanoparticles-laden lenses during shelf life period. In-vivo study in rabbit tear fluid showed sustained release up to 14days. The study revealed the application of pH-sensitive nanoparticles-laden contact lenses for controlled release of cyclosporine without altering the optical and physical properties of lens material.
Assuntos
Lentes de Contato , Nanopartículas/química , Ácidos Polimetacrílicos/química , Animais , Feminino , Concentração de Íons de Hidrogênio , Cinética , Masculino , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Coelhos , Difração de Raios XRESUMO
The effect of surfactant chain lengths [sodium caprylate (C8), Tween 20 (C12), Tween 80 (C18)] and the molecular weight of block copolymers [Pluronic F68 and Pluronic F 127] were studied to determine the stability of the microemulsion and its effect on release kinetics from cyclosporine-loaded microemulsion-laden hydrogel contact lenses in this work. Globule size and dilution tests (transmittance) suggested that the stability of the microemulsion increases with increase in the carbon chain lengths of surfactants and the molecular weight of pluronics. The optical transmittance of direct drug-laden contact lenses [DL-100] was low due to the precipitation of hydrophobic drugs in the lenses, while in microemulsion-laden lenses, the transmittance was improved when stability of the microemulsion was achieved. The results of in vitro release kinetics revealed that drug release was sustained to a greater extent as the stability of microemulsion was improved as well. This was evident in batch PF127-T80, which showed sustained release for 15days in comparison to batch DL-100, which showed release up to 7days. An in vivo drug release study in rabbit tear fluid showed significant increase in mean residence time (MRT) and area under curve (AUC) with PF-127-T80 lenses (stable microemulsion) in comparison to PF-68-SC lenses (unstable microemulsion) and DL-100 lenses. This study revealed the correlation between the stability of microemulsion and the release kinetics of drugs from contact lenses. Thus, it was inferred that the stable microemulsion batches sustained the release of hydrophobic drugs, such as cyclosporine from contact lenses for an extended period of time without altering critical lens properties.
Assuntos
Lentes de Contato , Liberação Controlada de Fármacos , Tensoativos/química , Animais , Preparações de Ação Retardada , Cinética , Poloxâmero , Polissorbatos , CoelhosRESUMO
Contact lenses are widely used for ophthalmic drug delivery, but incorporation of drug or formulation in the contact lenses affects its optical and physical property. In the present study, we have designed a novel hyaluronic acid (HA)-laden ring implant contact lenses (modified cast moulding method), to circumvent the changes in critical lens property. The objective was to improve the ocular residence time of HA, by providing sustained ocular HA delivery through implant contact lenses for the treatment of dry eye syndrome. Optimization of HA-implant was carried out using 32 factorial design by tailoring the amount of cross linker and thickness of implant, to achieve sustained HA release with constraint on effective ion diffusivity. The in vivo pharmacokinetic study in rabbit tear fluid showed sustained HA release up to 15days, by fabricating implant (80µgHA loading) with 78.4µm thickness (total thickness of lens=100µm) using 0.925% of cross linker, with effective ion diffusivity>1.5×10-6mm2/min. In vivo efficacy study in benzalkonium chloride induced dry eye syndrome rabbits showed faster healing with implant contact lenses in comparison to positive control group. The study demonstrated the promising potential of implantation technology to deliver hyaluronic acid without compromising optical and physical properties of contact lens. STATEMENT OF SIGNIFICANCE: The limitation of contact lenses to be used as therapeutic device for controlled drug delivery is focused in this study. Incorporation of drug or formulation in the biomaterial affects the optical and physical property of contact lenses. The significance of project was to design a novel hyaluronic acid-laden ring implant contact lenses, to by-pass the changes in critical property of biomaterial.
Assuntos
Lentes de Contato Hidrofílicas , Sistemas de Liberação de Medicamentos/métodos , Síndromes do Olho Seco/tratamento farmacológico , Ácido Hialurônico/administração & dosagem , Animais , Compostos de Benzalcônio/toxicidade , Materiais Biocompatíveis , Modelos Animais de Doenças , Implantes de Medicamento , Síndromes do Olho Seco/induzido quimicamente , Síndromes do Olho Seco/metabolismo , Feminino , Humanos , Ácido Hialurônico/farmacocinética , Técnicas In Vitro , Masculino , Teste de Materiais , Coelhos , Lágrimas/efeitos dos fármacos , Lágrimas/metabolismoRESUMO
Glaucoma is commonly treated using eye drops, which is highly inefficient due to rapid clearance (low residence time) from ocular surface. Contact lenses are ideally suited for controlled drug delivery to cornea, but incorporation of any drug loaded particulate system (formulation) affect the optical and physical property of contact lenses. The objective of the present work was to implant timolol maleate (TM) loaded ethyl cellulose nanoparticle-laden ring in hydrogel contact lenses that could provide controlled drug delivery at therapeutic rates without compromising critical lens properties. TM-implant lenses were developed, by dispersing TM encapsulated ethyl cellulose nanoparticles in acrylate hydrogel (fabricated as ring implant) and implanted the same in hydrogel contact lenses (sandwich system). The TM-ethyl cellulose nanoparticles were prepared by double emulsion method at different ratios of TM to ethyl cellulose. The X-ray diffraction studies revealed the transformation of TM to amorphous state. In vitro release kinetic data showed sustained drug release within the therapeutic window for 168h (NP 1:3 batch) with 150µg loading. Cytotoxicity and ocular irritation study demonstrated the safety of TM-implant contact lenses. In vivo pharmacokinetic studies in rabbit tear fluid showed significant increase in mean residence time (MRT) and area under curve (AUC), with TM-implant contact lenses in comparison to eye drop therapy. In vivo pharmacodynamic data in rabbit model showed sustained reduction in intra ocular pressure for 192h. The study demonstrated the promising potential of implantation technology to treat glaucoma using contact lenses, and could serve as a platform for other ocular diseases.
Assuntos
Anti-Hipertensivos/administração & dosagem , Lentes de Contato , Preparações de Ação Retardada/química , Glaucoma/tratamento farmacológico , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Soluções Oftálmicas/administração & dosagem , Timolol/administração & dosagem , Animais , Anti-Hipertensivos/uso terapêutico , Sistemas de Liberação de Medicamentos/instrumentação , Desenho de Equipamento , Feminino , Glaucoma/fisiopatologia , Pressão Intraocular/efeitos dos fármacos , Masculino , Soluções Oftálmicas/uso terapêutico , Coelhos , Timolol/uso terapêuticoRESUMO
OBJECTIVE: Present investigation was undertaken to study the effectiveness of hydroalcoholic extract of roots of Boerhaavia diffusa in experimental benign prostatic hyperplasia (BPH) in rats using various animal models. MATERIALS AND METHODS: BPH in rats was induced by subcutaneous injection of testosterone (5 mg/kg) daily for 28 days. Rats were divided in to five groups (six rats each). A negative control group received arachis oil (1 ml/kg s.c.) and four groups were injected testosterone. These four groups were further divided into reference group (finasteride 1 mg/kg), model group (testosterone), study group A (B. diffusa 100 mg/kg), and study group B (B. diffusa 250 mg/kg). On the 29(th) day, rats were sacrificed and body weight, prostate weight, bladder weight, and serum testosterone level were measured and histological studies were carried out. Further in vitro analysis of B. diffusa extract on contractility of isolated rat vas deferens and prostate gland, produced by exogenously administered agonists were carried out. All results were expressed as mean ± SEM. 0 Data were analyzed by one-way analysis of variance followed by Tukey's test. RESULTS: B. diffusa (100 mg/kg) treatment for 28 days resulted in significant inhibition of prostate growth (P < 0.05). Drug extract did not have significant change on serum testosterone level. Histopathological analysis of prostate gland supported above results. Results of in vitro experiment suggest that extracts had attenuated the contractile responses of isolated vas deferens and prostate gland to exogenously applied agonists. CONCLUSION: The results suggested that treatment with B. diffusa may improve symptoms of disease and inhibit the increased prostate size. In vitro study implies that herbal extracts has the machinery to produce beneficial effect on prostatic smooth muscle, which would relieve the urinary symptoms of disease. B. diffusa could be a potential source of new treatment of prostatic hyperplasia.
Assuntos
Nyctaginaceae , Extratos Vegetais/uso terapêutico , Hiperplasia Prostática/tratamento farmacológico , Animais , Modelos Animais de Doenças , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Raízes de Plantas , Próstata/efeitos dos fármacos , Próstata/patologia , Próstata/fisiologia , Hiperplasia Prostática/induzido quimicamente , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patologia , Ratos , Ratos Wistar , Testosterona , Bexiga Urinária/anatomia & histologia , Bexiga Urinária/efeitos dos fármacos , Ducto Deferente/efeitos dos fármacos , Ducto Deferente/fisiologiaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: A well-known traditional herb Solanum xanthocarpum is widely used in India for the management of different ailments including urolithiasis. This study was designed to rationalize the use of Solanum xanthocarpum in kidney stone and to investigate its mechanism of action. MATERIALS AND METHODS: The saponin rich fraction prepared from fruits of Solanum xanthocarpum (SXS) was evaluated for antiurolithiatic activity by in vitro and in vivo studies. In ethylene glycol (EG, 0.75% in drinking water for 28 days) induced urolithiasis model, two different experimental doses (20 mg/kg and 40 mg/kg, p.o., for 28 days) of saponin rich fraction were selected by dose fixation study. After 28 days, various biochemical parameters were measured in urine, serum and kidney homogenate. Kidneys were also subjected to histopathological analysis. RESULTS: In vitro calcium oxalate crystal (CaOx) nucleation as well as aggregation was inhibited in artificial urine solution by SXS. The lithogenic treatment caused polyuria, damage renal function and oxidative stress, manifested as increased malondialdehyde, depleted reduced glutathione and decreased antioxidant enzyme catalase activities of the kidneys, which were prevented by simultaneous administration with SXS. Lithogenic treatment also caused crystalluria, hyperoxaluria, hypercalciuria, hypocitrauria, and hypomagnesaemia. Deposition of CaOx in renal tissue and cellular injury were seen in histopathology. Co-administration of SXS had potential to prevent these pathological changes due to lithogenic treatment. Moreover, SXS raised level of glycosaminoglycan, a stone inhibitor macromolecule found in urine which decreased. CONCLUSION: The antiurolithiatic activity in Solanum xanthocarpum is mediated possibly through the inhibition of CaOx crystal formation and its effect on the urinary concentration of stone-forming constituents and nephrolithiasis inducing factors and this study rationalizes its medicinal use in urolithiasis.
Assuntos
Fitoterapia , Extratos Vegetais/uso terapêutico , Saponinas/uso terapêutico , Solanum , Urolitíase/tratamento farmacológico , Animais , Oxalato de Cálcio/química , Oxalato de Cálcio/urina , Cristalização , Modelos Animais de Doenças , Etilenoglicol , Feminino , Frutas , Masculino , Extratos Vegetais/análise , Ratos , Ratos Wistar , Saponinas/análise , Testes de Toxicidade Aguda , Urolitíase/induzido quimicamente , Urolitíase/patologia , Urolitíase/urinaRESUMO
OBJECTIVE: Aqueous root extract of Oroxylum indicum was evaluated in rats against dinitrobenzene sulfonic acid (DNBS) induced colitis. MATERIALS AND METHODS: Rats were pre-treated orally for seven days and continued for four days after the induction of colitis with OI(aq) (100, 200, and 400 mg/kg) or vehicle. Colitis was induced by intracolonic instillation of 25 mg of DNBS per rat dissolved in 50% alcohol and 4 days later, the colonic mucosal damage was analyzed along with food intake, body weight, colon weight, spleen weight, histological damage, myeloperoxidase (MPO) activity, malondialdehyde (MDA) levels, reduced glutathione (GSH), and nitric oxide levels in colonic tissue homogenate. RESULTS: Significant reduction in gross damage area, weight loss and increase in colonic and spleen weight were evident in test substance-pretreated animals' dose dependently as compared to vehicle treated control. These effects were confirmed biochemically by a reduction in colonic myeloperoxidase activity, malondialdehyde levels, nitric oxide levels, and increase in reduced glutathione (GSH) levels. Furthermore, microscopic examination revealed diminution of inflammatory cell infiltration and submucosal edema in colon segments of rats treated with OI(aq). CONCLUSION: The results demonstrate the protective effect of OI(aq) in the animal model of acute colitis possibly through an antioxidant, anti-lipoperoxidative or due to reduction in nitric oxide generation.
RESUMO
The aqueous and ethanolic extracts of C. grandis (Family: Leguminosae) were evaluated for antidiabetic activity by a glucose tolerance test, in normal rats and alloxan-induced diabetic rats. The aqueous and ethanolic extracts showed that they significantly lowered the blood glucose levels to normal in the glucose tolerance test. In alloxan-induced diabetic rats the maximum reduction in blood glucose was observed after three hours, at a dose level of 150 mg/kg of body weight. The percentage of protection given by the aqueous and ethanolic extracts was 32.72 and 46.42%, respectively. In the long-term treatment of alloxan-induced diabetic rats, the degree of protection was determined by measuring the blood glucose, cholesterol, and triglycerides on the tenth day. Both the extracts showed a significant antidiabetic activity comparable to that of glibenclamide. These results showed that the Cassia grandis possessed significant antidiabetic activity.