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2.
Nat Prod Res ; : 1-14, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38198584

RESUMEN

The phytochemical investigation of Psidium guajava leaves led to the isolation of total nineteen compounds which belongs to meroterpenoids, flavonoid, phenolics, and triterpenoids. The compounds were isolated using extensive chromatography techniques and identified as psiguanol (4), as new compound along with guajadial (1), psidial A (2), ß-caryophyllene (3), quercetin (5), avicularin (6), guaijaverin (7), hyperin (8), rutin (9), ursolic acid (10), corosolic acid (11), asiatic acid (12), ß-sitosterol (13), ß-sitosterol-D-glucoside (14), ellagic acid (15), 3,3',4'-trimethylellagic acid 4-O-glucoside (16), protocatechuic acid (17), gallic acid (18), and tricosanoic acid (19) as known molecules. The compound 16 was isolated for the first time from this plant. The isolated compounds were evaluated for vasorelaxation activity in rat aorta cells and it was observed that compound 4 exhibited the most potent vasorelaxation response in the ex-vivo model in isolated rat aorta cells. Mechanistically, the vasorelaxation activity of 4 was mediated through cGMP-dependent BKCa channel opening.

3.
Altern Lab Anim ; 51(4): 263-288, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37282515

RESUMEN

Animal experimentation has been integral to drug discovery and development and safety assessment for many years, since it provides insights into the mechanisms of drug efficacy and toxicity (e.g. pharmacology, pharmacokinetics and pharmacodynamics). However, due to species differences in physiology, metabolism and sensitivity to drugs, the animal models can often fail to replicate the effects of drugs and chemicals in human patients, workers and consumers. Researchers across the globe are increasingly applying the Three Rs principles by employing innovative methods in research and testing. The Three Rs concept focuses on: the replacement of animal models (e.g. with in vitro and in silico models or human studies), on the reduction of the number of animals required to achieve research objectives, and on the refinement of existing experimental practices (e.g. eliminating distress and enhancing animal wellbeing). For the last two years, Oncoseek Bio-Acasta Health, a 3-D cell culture-based cutting-edge translational biotechnology company, has organised an annual International Conference on 3Rs Research and Progress. This series of global conferences aims to bring together researchers with diverse expertise and interests, and provides a platform where they can share and discuss their research to promote practices according to the Three Rs principles. In November 2022, the 3rd international conference, Advances in Animal Models and Cutting-Edge Research in Alternatives, took place at the GITAM University in Vishakhapatnam (AP, India) in a hybrid format (i.e. online and in-person). These conference proceedings provide details of the presentations, which were categorised under five different topic sessions. It also describes a special interactive session on in silico strategies for preclinical research in oncology, which was held at the end of the first day.


Asunto(s)
Experimentación Animal , Animales , Humanos , Modelos Animales , Descubrimiento de Drogas , India , Alternativas a las Pruebas en Animales
4.
Infect Disord Drug Targets ; 23(3): e041022209552, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36200205

RESUMEN

BACKGROUND: Tuberculosis (TB) is one of the fatal infectious diseases, making it one of the causes of death in the infectious mortality strata, and it is of prime concern globally. It is spread by a causative agent called Mycobacterium tuberculosis (Mtb) which gets ingressed within the host cells. The current clinical interventions have been associated with various limitations, such as a long treatment regimen (6 months), low lipophilicity of drugs to penetrate the bacterial cell, associated side effects and emerging incidence of multiple drug-resistant strains. Despite these limitations, Isoniazid (INH), a first-line agent, remains a drug of choice to date due to its effectiveness. However, INH is associated with poor penetration into the bacteria cell wall and ultimately leads to the low therapeutic distribution of drugs into the lungs. METHODS: Studies have shown that the structural modifications of INH by introducing more lipophilic moiety could lead to its better penetration into the bacterial cell wall resulting in better anti-TB activities. RESULTS: This review updates various studies conducted on INH derivatives as anti-tubercular (Anti-TB) agents, including in silico and preclinical investigations. In addition, updates on clinical investigations of novel anti-TB molecules have also been highlighted. CONCLUSION: The article focuses on the structural modification of various INH derivatives reported, including the in vitro studies and molecular modelling preclinical and clinical investigations of various INH derivatives.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , Isoniazida/farmacología , Antituberculosos/uso terapéutico , Tuberculosis/tratamiento farmacológico , Tuberculosis/microbiología , Modelos Moleculares
5.
J Drug Target ; 29(1): 46-59, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32729731

RESUMEN

In current clinical settings, frequent intravitreal (IVT) injections of anti-vascular endothelial growth factors are used due to their short in-vivo half-life and rapid clearance from the back of the eye. The IVT injections are associated with pain, risk of infection, retinal detachment, and financial burden. Biologics molecules can undergo physical, chemical, and enzymatic degradation during formulation development and in the biological environment. Moreover, the complex ocular structures also act as a rate-limiting barrier for these biologics. Thus, delivering stable and clinically relevant biologics concentration to the back of the eye is still a challenge. Compare to other drug delivery platforms, injectable in-situ gelling depot systems (IISGDs) have emerged as an effective system for biologics delivery. In this review, we have discussed various biologics used in ocular therapeutics and their associated challenges. Different routes of delivery and associated tissue barriers are also discussed. Different types of IISGDs developed to date for biologics delivery to the back of the eye were also covered. To conclude, various critical parameters related to the formulation development process and injectable depot systems that need careful consideration and further investigations were highlighted.


Asunto(s)
Productos Biológicos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Inyecciones Intravítreas/métodos , Retina/efectos de los fármacos , Animales , Productos Biológicos/metabolismo , Ensayos Clínicos como Asunto/métodos , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/metabolismo , Geles , Humanos , Retina/metabolismo
6.
Artículo en Inglés | MEDLINE | ID: mdl-28425224

RESUMEN

Effective drug delivery to the retina still remains a challenge due to ocular elimination mechanisms and complex barriers that selectively limit the entry of drugs into the eye. To overcome these barriers, frequent intravitreal injections are currently used to achieve high drug concentrations in vitreous and retina. However, these repetitive injections may result in several side effects. Recent advancements in the field of nanoparticle-based drug delivery could overcome some of these unmet needs and various preclinical studies conducted to date have demonstrated promising results of nanotherapies in the treatment of retinal diseases. Compared to the majority of commercially available ocular implants, the biodegradable nature of most nanoparticles (NPs) avoids the need for surgical implantation and removal after the release of the payload. In addition, the sustained drug release from NPs over an extended period of time reduces the need for frequent intravitreal injections and the risk of associated side effects. The nanometer size and highly modifiable surface properties make NPs excellent candidates for targeted ocular drug delivery. Studies have shown that nanocarriers enhance the intravitreal half-life and thus bioavailability of a number of drugs including proteins and peptides. In addition, they have shown promising results in delivering genetic material to the retinal tissues by protecting it from possible intravitreal degradation. This review covers the various challenges associated with drug delivery to the posterior segment of the eye, particularly the retina, and highlights the application of nanocarriers to overcome these challenges in context with recent advances in preclinical studies. WIREs Nanomed Nanobiotechnol 2018, 10:e1473. doi: 10.1002/wnan.1473 This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Implantable Materials and Surgical Technologies > Nanomaterials and Implants.


Asunto(s)
Portadores de Fármacos , Nanomedicina , Nanopartículas , Enfermedades de la Retina/tratamiento farmacológico , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/uso terapéutico , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/uso terapéutico , Humanos , Inyecciones Intravítreas , Nanopartículas/administración & dosificación , Nanopartículas/uso terapéutico
7.
Pharm Dev Technol ; 23(4): 324-333, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27670289

RESUMEN

Frequent intravitreal injections are currently used to overcome the ocular barriers and provide sufficient drug to the posterior eye segment. However, intravitreal injections have been associated with a number of complications and high treatment costs. To overcome these limitations, peptide-loaded poly(d,l-lactic-co-glycolic acid) nanoparticles (PLGA NPs) were developed using the nanoprecipitation technique and were optimized via Box-Behnken Design (BBD) and Response Surface Methodology (RSM). Developed NPs were evaluated for potential toxicity and cell apoptosis using the zebrafish embryo toxicity (ZET) model with titanium dioxide NPs and ethanol (1% v/v) serving as positive controls. Developed NPs had a size of 75.6-153.8 nm, a polydispersity index between 0.11 and 0.25 and a zeta potential of -9.4 to -46.0 mV. Loaded peptide was found to be stable under various experimental conditions tested. BBD and RSM were validated through the characterization of optimized formulations. Survival and hatching rates of NP-treated zebrafish 0-144 h post-fertilization were found to be normal with no significant malformations. Cellular apoptosis studies also endorsed the non-cytotoxic nature of the NPs. The overall results indicate that optimized PLGA nanoparticles could be a promising platform for efficient peptide delivery to the posterior segment of the eye.


Asunto(s)
Portadores de Fármacos/toxicidad , Ácido Láctico/toxicidad , Nanopartículas/toxicidad , Péptidos/administración & dosificación , Ácido Poliglicólico/toxicidad , Animales , Apoptosis/efectos de los fármacos , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/efectos adversos , Embrión no Mamífero/citología , Embrión no Mamífero/efectos de los fármacos , Embrión no Mamífero/fisiología , Inyecciones Intravítreas , Ácido Láctico/administración & dosificación , Ácido Láctico/química , Nanopartículas/administración & dosificación , Nanopartículas/química , Péptidos/química , Ácido Poliglicólico/administración & dosificación , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Pruebas de Toxicidad , Pez Cebra/embriología
8.
Med Hypotheses ; 103: 5-9, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28571808

RESUMEN

Diseases affecting the posterior segment the eye, such as age-related macular degeneration (AMD), are the leading cause of blindness worldwide. Conventional dosage forms, such as eye drops, have to surmount several elimination mechanisms and complex barriers to achieve therapeutic concentrations at the target site often resulting in low anterior segment bioavailability (ca. 2-5%) with generally none of the drug reaching posterior segment tissues. Thus, frequent intravitreal injections are currently required to treat retinal conditions which have been associated with poor patient compliance due to pain, risk of infection, hemorrhages, retinal detachment and high treatment related costs. To partially overcome these issues, ocular implants have been developed for some posterior segment indications; however, the majority require surgical implantation and removal at the end of the intended treatment period. The transparent nature of the cornea and lens render light-responsive systems an attractive strategy for the management of diseases affecting the back of the eye. Light-responsive in situ forming injectable implants (ISFIs) offer various benefits such as ease of application in a minimally invasive manner and more site specific control over drug release. Moreover, the biodegradable nature of such implants avoids the need for surgical removal after release of the payload. Incorporating drug-loaded polymeric nanoparticles (NPs) into these implants may reduce the high initial burst release from the polymeric matrix and further sustain drug release thus avoiding the need for frequent injections as well as minimizing associated side effects. However, light-responsive systems for ophthalmic application are still in their early stages of development with limited reports on their safety and effectiveness. We hypothesize that the innovative design and properties of NP-containing light-responsive ISFIs can serve as a platform for effective management of ocular diseases requiring long term treatment.


Asunto(s)
Implantes Absorbibles , Sistemas de Liberación de Medicamentos/métodos , Degeneración Macular/tratamiento farmacológico , Nanopartículas/química , Enfermedades de la Retina/tratamiento farmacológico , Barrera Hematorretinal , Córnea/efectos de los fármacos , Difusión , Epitelio/efectos de los fármacos , Humanos , Luz , Modelos Teóricos , Soluciones Oftálmicas , Péptidos/uso terapéutico , Polímeros/química
9.
Mol Pharm ; 14(6): 2056-2069, 2017 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-28471177

RESUMEN

Topical drug administration for back of the eye delivery is extremely challenging due to the presence of protection mechanisms and physiological barriers. Self-assembled polymeric nanomicelles have emerged as promising vehicles for drug delivery. Apart from serving as an inert nanocarrier for therapeutic agents, polymeric nanomicelles are known to bypass mononuclear phagocytic system (MPS) and efflux transporters thereby improving drug bioavailability. In this investigation, a highly efficacious biotinylated lipid prodrug of cyclic cidofovir (B-C12-cCDF) was formulated within polymeric nanomicelles as a carrier for targeted retinal delivery. Polymeric nanomicelles were prepared from polyoxyethylene hydrogenated castor oil 40 (HCO-40) and octoxynol 40 (OC-40). In vitro release studies revealed that B-C12-cCDF-loaded nanomicelles released B-C12-cCDF at a faster rate in stimulated tear fluid (STF) in comparison to PBST. MTT and LDH assays demonstrated negligible cytotoxicity of B-C12-cCDF-loaded nanomicelles relative to CDF and B-C12-cCDF in HRPE (human retinal pigment epithelial, D407), HCE-T (human corneal epithelial), and CCL 20.2 (human conjunctival epithelial) cells. Confocal laser scanning microscopy and flow cytometry analyses indicated that B-C12-cCDF-loaded nanomicelles were efficiently internalized into D407 and HCE-T cells in contrast to CDF and B-C12-cCDF. Moreover, little B-C12-cCDF was also observed in the nuclei after 24 h of incubation. Polymeric nanomicelles carrying the transporter targeted prodrug did not produce any cytotoxic effects and were internalized into the cells effectively. Permeability experiments across HCE-T cells further confirmed significant transport of prodrug loaded nanomicelles and their subsequent uptake into D407 cells. These findings indicate that HCO-40/OC-40 based polymeric nanomicelles could become a promising topical delivery system for ocular administration of antiviral agents.


Asunto(s)
Antivirales/química , Profármacos/química , Retina/metabolismo , Administración Oftálmica , Animales , Antivirales/administración & dosificación , Antivirales/uso terapéutico , Línea Celular , Retinitis por Citomegalovirus/tratamiento farmacológico , Sistemas de Liberación de Medicamentos/métodos , Humanos , Ratones , Micelas , Nanopartículas/química , Profármacos/administración & dosificación , Profármacos/uso terapéutico , Células RAW 264.7 , Retina/efectos de los fármacos
10.
J Control Release ; 248: 96-116, 2017 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-28087407

RESUMEN

Effective intraocular drug delivery poses a major challenge due to the presence of various elimination mechanisms and physiological barriers that result in low ocular bioavailability after topical application. Over the past decades, polymeric micelles have emerged as one of the most promising drug delivery platforms for the management of ocular diseases affecting the anterior (dry eye syndrome) and posterior (age-related macular degeneration, diabetic retinopathy and glaucoma) segments of the eye. Promising preclinical efficacy results from both in-vitro and in-vivo animal studies have led to their steady progression through clinical trials. The mucoadhesive nature of these polymeric micelles results in enhanced contact with the ocular surface while their small size allows better tissue penetration. Most importantly, being highly water soluble, these polymeric micelles generate clear aqueous solutions which allows easy application in the form of eye drops without any vision interference. Enhanced stability, larger cargo capacity, non-toxicity, ease of surface modification and controlled drug release are additional advantages with polymeric micelles. Finally, simple and cost effective fabrication techniques render their industrial acceptance relatively high. This review summarizes structural frameworks, methods of preparation, physicochemical properties, patented inventions and recent advances of these micelles as effective carriers for ocular drug delivery highlighting their performance in preclinical studies.


Asunto(s)
Portadores de Fármacos/química , Micelas , Preparaciones Farmacéuticas/administración & dosificación , Polímeros/química , Administración Oftálmica , Animales , Disponibilidad Biológica , Portadores de Fármacos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Síndromes de Ojo Seco/tratamiento farmacológico , Ojo/metabolismo , Oftalmopatías/tratamiento farmacológico , Humanos , Soluciones Oftálmicas/administración & dosificación , Soluciones Oftálmicas/química , Preparaciones Farmacéuticas/química , Polímeros/administración & dosificación , Solubilidad
11.
J Pharm Anal ; 7(6): 365-373, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29404061

RESUMEN

Connexin43 mimetic peptide (Cx43MP) has been intensively investigated for its therapeutic effect in the management of inflammatory eye conditions, spinal cord injury, wound healing and ischemia-induced brain damage. Here, we report on a validated stability-indicating reversed-phase high performance liquid chromatography (RP-HPLC) method for the quantification of Cx43MP under stress conditions. These included exposure to acid/base, light, oxidation and high temperature. In addition, the degradation kinetics of the peptide were evaluated in bovine vitreous and drug-free human plasma at 37 °C. Detection of Cx43MP was carried out at 214 nm with a retention time of 7.5 min. The method showed excellent linearity over the concentration range of 0.9-250 µg/mL (R2 ≥ 0.998), and the limits of detection (LOD) and quantification (LOQ) were found to be 0.90 and 2.98 µg/mL, respectively. The accuracy of the method determined by the mean percentage recovery at 7.8, 62.5 and 250 µg/mL was 96.79%, 98.25% and 99.06% with a RSD of < 2.2%. Accelerated stability studies revealed that Cx43MP was more sensitive to basic conditions and completely degraded within 24 h at 37 °C (0% recovery) and within 12 h at 80 °C (0.34% recovery). Cx43MP was found to be more stable in bovine vitreous (t1/2slow= 171.8 min) compared to human plasma (t1/2slow = 39.3 min) at 37 °C according to the two phase degradation kinetic model. These findings are important for further pre-clinical development of Cx43MP.

12.
Mol Neurobiol ; 54(7): 5632-5645, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-27624385

RESUMEN

Parkinson's disease (PD) having a complex and multi-factorial neuropathology includes mainly the degeneration of the dopaminergic nigrostriatal pathway, which is a cumulative effect of depleted endogenous antioxidant enzymes, increased oxidative DNA damage, mitochondrial dysfunction, excitotoxicity, and neuroinflammation. The present study was designed to investigate the neuroprotective effect of a potent antioxidant from Urtica dioica in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of parkinsonism. MPTP was administered intranigrally for the induction of PD in male Wistar rats. Behavioral alterations were assessed in between the study period. Animals were sacrificed immediately after behavioral session, and different biochemical, cellular, and neurochemical parameters were measured. Intranigrally repeated administration of MPTP showed significant impairment of motor co-ordination and marked increase of mito-oxidative damage and neuroinflammation in rats. Intranigral MPTP significantly decreases the dopamine and its metabolites with impairment of dopaminergic cell density in rat brain. However, post-treatment with the potent antioxidant fraction of Urtica dioica Linn. (UD) (20, 40, 80 mg/kg) improved the motor function, mito-oxidative defense alteration significantly and dose dependently in MPTP-treated rats. In addition, the potent antioxidant fraction of UD attenuated the pro-inflammatory cytokines (TNF-α and IL-ß) and restored the level of dopamine and its metabolites in MPTP-induced PD in rats. Moreover, minocycline (30 mg/kg) with lower dose of UD (20 mg/kg) had significantly potentiated the protective effect of minocycline as compared to its effect with other individual drug-treated groups. In conclusion, Urtica dioica protected the dopaminergic neurons probably by reducing mito-oxidative damage, neuroinflammation, and cellular alteration along with enhanced neurotrophic potential. The above results revealed that the antioxidant rich fraction of UD contain flavonoids and phenolic compounds, which have a promising approach in therapeutics of PD.


Asunto(s)
1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Antioxidantes/farmacología , Conducta Animal/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Urtica dioica/efectos de los fármacos , Animales , Cuerpo Estriado/efectos de los fármacos , Modelos Animales de Enfermedad , Masculino , Ratones , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Ratas
13.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-663959

RESUMEN

Connexin43 mimetic peptide (Cx43MP) has been intensively investigated for its therapeutic effect in the management of inflammatory eye conditions, spinal cord injury, wound healing and ischemia-induced brain damage. Here, we report on a validated stability–indicating reversed-phase high performance liquid chromatography(RP-HPLC)method for the quantification of Cx43MP under stress conditions.These included exposure to acid/base, light, oxidation and high temperature. In addition, the degradation kinetics of the peptide were evaluated in bovine vitreous and drug-free human plasma at 37 ℃. Detection of Cx43MP was carried out at 214 nm with a retention time of 7.5 min. The method showed excellent linearity over the concentration range of 0.9–250μg/mL(R2≥0.998),and the limits of detection(LOD)and quantification(LOQ) were found to be 0.90 and 2.98 μg/mL, respectively. The accuracy of the method determined by the mean percentage recovery at 7.8, 62.5 and 250μg/mL was 96.79%, 98.25% and 99.06% with a RSD of<2.2%. Accelerated stability studies revealed that Cx43MP was more sensitive to basic conditions and completely degraded within 24 h at 37 ℃(0% recovery)and within 12 h at 80 ℃(0.34% recovery).Cx43MP was found to be more stable in bovine vitreous(t1/2slow=171.8 min)compared to human plasma(t1/2slow=39.3 min)at 37 ℃ according to the two phase degradation kinetic model. These findings are important for further pre-clinical development of Cx43MP.

14.
Drug Deliv Transl Res ; 6(6): 763-770, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27371395

RESUMEN

This study aimed to develop and evaluate an ex vivo eye model for intravitreal drug sampling and tissue distribution of connexin43 mimetic peptide (Cx43MP) following intravitreal injection using the microdialysis technique and LC-MS/MS. An LC-MS/MS method was developed, validated, and applied for quantification of Cx43MP in ocular tissues. Microdialysis probes were calibrated for in vitro recovery studies. Bovine eyes were fixed in a customized eye holder and after intravitreal injection of Cx43MP, microdialysis probes were implanted in the vitreous body. Vitreous samples were collected at particular time intervals over 24 h. Moreover, 24 and 48 h after intravitreal injection ocular tissues were collected, processed, and analyzed for Cx43MP concentrations using LC-MS/MS. The LC-MS/MS method showed good linearity (r 2 = 0.9991). The mean percent recovery for lower (LQC), medium (MQC), and higher quality control (HQC) (0.244, 3.906, and 125 µg/mL) was found to be 83.83, 84.92, and 94.52, respectively, with accuracy ranges between 96 and 99 % and limits of detection (LOD) and quantification (LOQ) of 0.122 and 0.412 µg/mL. The in vitro recovery of the probes was found to be over 80 %. As per microdialysis sample analysis, the Cx43MP concentration was found to increase slowly in the vitreous body up to 16 h and thereafter declined. After 48 h, the Cx43MP concentration was higher in vitreous, cornea, and retina compared to lens, iris, and aqueous humor. This ex vivo model may therefore be a useful tool to investigate intravitreal kinetics and ocular disposition of therapeutic molecules after intravitreal injection.


Asunto(s)
Conexina 43/farmacocinética , Ojo/metabolismo , Péptidos/farmacocinética , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Conexina 43/administración & dosificación , Técnicas In Vitro , Inyecciones Intravítreas , Microdiálisis , Péptidos/administración & dosificación , Espectrometría de Masas en Tándem , Distribución Tisular
15.
Expert Opin Drug Deliv ; 13(7): 953-62, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26967153

RESUMEN

INTRODUCTION: Frequent intravitreal injections are currently the preferred treatment method for diseases affecting the posterior segment of the eye. However, these repeated injections have been associated with pain, risk of infection, hemorrhages, retinal detachment and high treatment costs. To overcome these limitations, light-responsive in situ forming injectable implants (ISFIs) may emerge as novel systems providing site-specific controlled drug delivery to the retinal tissues with great accuracy, safety, minimal invasiveness and high cost efficiency. AREA COVERED: Complex ocular barriers, routes for drug delivery, types of injectable implants, ocular application of light and benefits of light-responsive systems are discussed with regards to challenges and strategies employed for effective drug delivery to the posterior segment of the eye. In particular, we have highlighted photoresponsive moieties, photopolymerization mechanisms and different development strategies with their limitations as well as recent advancements in the field. EXPERT OPINION: Biodegradable light-responsive ISFIs are promising drug delivery systems that have shown a high degree of biocompatibility with sustained drug release in a number of applications. However, their use in intravitreal drug delivery is still in the very early stages. Issues related to the biocompatibility of the photoinitiator and the elimination of photo-degraded by-products from the ocular tissues need careful consideration, not only from a chemistry standpoint, but also from a biological perspective to improve the suitability of these systems for clinical applications.


Asunto(s)
Sistemas de Liberación de Medicamentos , Oftalmopatías/tratamiento farmacológico , Ojo/metabolismo , Preparaciones de Acción Retardada/administración & dosificación , Implantes de Medicamentos , Humanos , Inyecciones Intravítreas
16.
Exp Toxicol Pathol ; 67(2): 211-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25547370

RESUMEN

Accumulating evidence strongly suggests that gamma amino butyric acid (GABA) receptors play a crucial role in the pathogenesis of Parkinson's disease (PD). Therefore, the present study was designed to investigate the role of GABA-B receptor modulation in experimental models of MPTP-induced PD. MPTP was administered repeatedly on 1st, 7th and 14th day intranigrally for the induction of PD in Male Wistar rats. Baclofen (10 and 20mg/kg) and GABA-B antagonist CGP35348 (10mg/kg) were given after induction of PD for 14 days. Different behavioural tasks were performed during 1st, 14th, 21st, 28th days after MPTP injection and biochemical parameters were estimated on day 28th. Central administration of MPTP showed significant impairment of motor behaviour and marked increase of oxidative damage LPO and GSH in striatum and cortex. Pro-inflammatory cytokines like TNF-α and IL-ß were significantly increased in striatum region of MPTP treated rats. However, post treatment with baclofen significantly improved the motor abnormalities and attenuated the oxidative damage and neuro-inflammation in MPTP treated rats. CGP35348, GABA-B receptor antagonist, reversed the protective effect of baclofen GABA-B receptor play role in the neuroprotection. The present study concluded that baclofen produce beneficial effect against MPTP induced PD like symptoms rats through GABAergic mechanism.


Asunto(s)
1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Corteza Cerebral/efectos de los fármacos , Cuerpo Estriado/efectos de los fármacos , Trastornos Parkinsonianos/metabolismo , Receptores de GABA-B/metabolismo , Animales , Baclofeno/farmacología , Corteza Cerebral/inmunología , Corteza Cerebral/metabolismo , Cuerpo Estriado/inmunología , Cuerpo Estriado/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Agonistas de Receptores GABA-B/farmacología , Antagonistas de Receptores de GABA-B/farmacología , Peroxidación de Lípido/efectos de los fármacos , Masculino , Actividad Motora/efectos de los fármacos , Compuestos Organofosforados/farmacología , Estrés Oxidativo/efectos de los fármacos , Trastornos Parkinsonianos/etiología , Trastornos Parkinsonianos/fisiopatología , Ratas Wistar , Prueba de Desempeño de Rotación con Aceleración Constante
17.
J Renin Angiotensin Aldosterone Syst ; 16(4): 917-29, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24464858

RESUMEN

INTRODUCTION: Tardive dyskinesia is a serious motor disorder of the orofacial region, resulting from chronic neuroleptic treatment of schizophrenia. Candesartan (AT1 antagonist) and lisinopril (ACE inhibitor) has been reported to possess antioxidant and neuroprotective effects. The present study is designed to investigate the effect of candesartan and lisinopril on haloperidol-induced orofacial dyskinesia and oxidative damage in rats. MATERIALS AND METHODS: Tardive dyskinesia was induced by administering haloperidol (1 mg/kg i.p.) and concomitantly treated with candesartan (3 and 5 mg/kg p.o.) and lisinopril (10 and 15 mg/kg p.o.) for 3 weeks in male Wistar rats. Various behavioral parameters were assessed on days 0, 7, 14 and 21 and biochemical parameters were estimated at day 22. RESULTS: Chronic administration of haloperidol significantly increased stereotypic behaviors in rats, which were significantly improved by administration of candesartan and lisinopril. Chronic administration of haloperidol significantly increased oxidative stress and neuro-inflammation in the striatum region of the rat's brain. Co-administration of candesartan and lisinopril significantly attenuated the oxidative damage and neuro-inflammation in the haloperidol-treated rat. CONCLUSIONS: The present study supports the therapeutic use of candesartan and lisinopril in the treatment of typical antipsychotic-induced orofacial dyskinesia and possible antioxidant and neuro-inflammatory mechanisms.


Asunto(s)
Bencimidazoles/uso terapéutico , Haloperidol/efectos adversos , Lisinopril/uso terapéutico , Trastornos del Movimiento/tratamiento farmacológico , Tetrazoles/uso terapéutico , Animales , Antioxidantes/metabolismo , Compuestos de Bifenilo , Peso Corporal/efectos de los fármacos , Aseo Animal , Fuerza de la Mano , Interleucina-1beta/metabolismo , Masculino , Malondialdehído/metabolismo , Masticación , Aprendizaje por Laberinto/efectos de los fármacos , Memoria/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Trastornos del Movimiento/fisiopatología , Nitritos/metabolismo , Estrés Oxidativo/efectos de los fármacos , Ratas Wistar , Prueba de Desempeño de Rotación con Aceleración Constante , Conducta Estereotipada , Factor de Necrosis Tumoral alfa/metabolismo
18.
Neurotoxicology ; 44: 71-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25053526

RESUMEN

Parkinson's disease is a neurodegenerative disorder characterized by the loss of dopamine neurons in the substantia nigra pars compacta along with decreased striatal dopamine levels, and consequent extra pyramidal motor dysfunctions occur. It has been reported that Ceftriaxone, a ß-lactam antibiotic recently had shown to have neuroprotective effects in various neurodegenerative disorder. Therefore the present study was designed to investigate the effects of Ceftriaxone (CFX) in a MPTP model of Parkinson in rats. MPTP was administered intranigrally for the induction of PD in Male Wistar rats. Ceftriaxone (100 and 200mg/kg) and Ropinirole (1.5 and 3mg/kg) were given intraperitonially, after induction of Parkinson's disease for 14 days. Different behavioral performance was carried on 1st, 14th, 21st, 28th consecutive days and biochemical parameters were estimated on 28th day. Central administration of MPTP showed significant impairment of motor behavior and marked increase of oxidative damage and neuro-inflammmation in rats. However, post treatment with Ceftriaxone (100 and 200mg/kg) significantly improved the motor deficits and attenuated the oxidative damage indicating decreased rise of LPO and nitrite concentration and restored the decreased activities of endogenous antioxidant enzyme (Glutathione, Catalase, SOD). In addition Ceftriaxone also attenuates the pro-inflammatory cytokines like TNF-α and IL-ß in striatum region of MPTP induced PD in rats. Ropinirole (1.5mg/kg) pretreatment with sub-effective dose of a Ceftriaxone (100mg/kg) had significantly enhanced the protective effect of Ceftriaxone as compare to its effect with per se group. These results suggested that Ceftriaxone exhibit Neuroprotective effect by mediating brain antioxidant defense mechanism and by up regulating of dopaminergic pathway and down regulation of glutamatergic pathway.


Asunto(s)
Ceftriaxona/uso terapéutico , Intoxicación por MPTP/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Sustancia Negra/efectos de los fármacos , Sustancia Negra/metabolismo , Animales , Ceftriaxona/farmacología , Encefalitis/tratamiento farmacológico , Encefalitis/metabolismo , Indoles/farmacología , Indoles/uso terapéutico , Masculino , Actividad Motora/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Prueba de Desempeño de Rotación con Aceleración Constante
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