In-situ forming biodegradable implants for sustained Fluocinolone acetonide release to the posterior eye: In-vitro and in-vivo investigations in rabbits.

Delivering medication to the posterior segment of the eye presents a significant challenge. Intravitreal injection has emerged as the preferred method for drug delivery to this area. However, current injectable non-biodegradable implants for fluocinolone acetonide (FA) require surgical removal after prolonged drug release, potentially affecting patient compliance. This study aimed to develop an in-situ forming biodegradable implant (ISFBI) optimal formulation containing PLGA504H and PLGA756S (50:50 w/w%) with the additive NMP solvent. The goal was to achieve slow and controlled release of FA over a two-month period with lower burst release, following a single intravitreal injection. Through morphology, rheology, stability and in-vitro release evaluations, the optimal formulation demonstrated low viscosity (0.12-1.25 Pa. s) and sustained release of FA at a rate of 0.36 µg/day from the third day up to two months. Furthermore, histopathology and in-vivo studies were conducted after intravitreal injection of the optimal formulation in rabbits' eye. Pharmacokinetic analysis demonstrated mean residence time (MRT) of 20.02 ± 0.6 days, half-life (t1/2) of 18.80 ± 0.4 days, and clearance (Cl) of 0.29 ± 0.03 ml/h for FA in the vitreous humor, indicating sustained and slow absorption of FA by the targeted retinal tissue from vitrea over the two-month period and eliminating through the anterior section of the eye, as revealed by its presence in the aqueous humor. Additionally, FA exhibited no detection in the blood and no evidence of systemic side effects or damage on the retinal layer and other organs. Based on these findings, it can be concluded that in-situ forming injectable biodegradable PLGA implants can show promise as a long-acting and controlled-release system for intraocular drug delivery.

Prolonged local delivery of doxorubicin to cancer cells using lipid liquid crystalline system.

Exploring efficient strategies to eradicate the tumor tissue and enhance patient outcomes still remained a serious challenge. Systemic toxicity of the current chemotherapeutics and their low concentration in the tumor site limited reaching a practical approach in their administration and combinational therapy. Besides, complicated delivery platforms could not receive the marketing approval due to difficulties in scale up procedures. To this aim, we developed a simple injectable local delivery platform which provided a sufficient dose of the chemotherapeutic in the cancerous tissue with sustained release properties. Herein, various injectable in situ forming LLC formulations loaded with doxorubicin (DOX) were developed. Although there were many previous studies on lipid liquid crystal (LLC) based formulations, their performance as an injectable intratumoral depot system for local chemotherapy has not been extensively investigated yet. In the current study we developed 18 formulations of DOX loaded LLCs using Box-Behnken method via different ratios of phosphatidyl choline: sorbitan monooleate (PC: SMO), N-Methyl-2-pyrrolidone (NMP), and tween 80. The physicochemical properties of the formulations were investigated and their in vivo tumor inhibition efficiencies in C26 tumor bearing mouse model was further studied. The results indicated that DOX loaded PC: SMO/NMP/Tween 80 (50:50/50/2 w/w%) and DOX loaded PC: SMO/NMP (50:50/50 w/w%) formulations were syringeable with pseudoplastic behavior. Also, they could release the cargo in a sustained manner for 60 days. Compared to intravascular administration of DOX, intratumoral injection of the developed formulations led to a significant decrease in tumor volume and enhancement of the survival rate in murine tumor model. Additionally, animal imaging studies proved their prolonged accumulation in the tumor site. Histopathological studies showed that treatment with the DOX-loaded LLC formulations did not cause any systemic toxicity to vital organs. Taken together, we believe that the developed simple and efficient local delivery platform can be further used in combinational therapies and treatment of various solid tumors.

Enhanced wound-healing efficacy of electrospun mesoporous hydroxyapatite nanoparticle-loaded chitosan nanofiber developed using pluronic F127.

One of the goals of wound repairing is to mimic the function and architecture of the native extracellular matrix (ECM). To this end, for the first time, we used pluronic F127 and mesoporous rod-like hydroxyapatite nanoparticles (mr-HAP NPs) simultaneously to prepare a novel low-diameter electrospun ECM-mimicking wound dressing based on a mixture of chitosan and polyethylene oxide. F127 is used as a surface tension regulator of the polymer solution. In addition, F127 has the special ability to reduce the size of nanofibers. mr-HAP NPs are used as cell proliferation accelerators which also improve the mechanical properties and water uptake capacity of the as-prepared dressing. The average size of nanofibers in the presence of F127 was about 110 nm which was more than 2.5 times lower than nanofibers prepared without F127. The water uptake capacity was evaluated to investigate the wound exudate absorption capacity of the wound dressing. It was observed that the incorporation of mr-HAP NPs into wound dressing structure increases the water uptake capacity by more than 2.5 times. Alongside the evaluation of cytocompatibility through in vitro cell viability assay, the wound healing efficacy was also determined in full-thickness skin wounds in a rat model for 15 days. The cytocompatible wound dressing showed significantly higher wound closure efficacy than the control group so the wounds healed entirely on the last day of the treatment period. As well, the pathology analysis proved better granulation tissue development and greater re-epithelialization. These findings are by virtue of the improved mechanical properties, accelerated cell migration and proliferation, proper environment for oxygen exchange, and enhanced exudate uptake of the wound dressing. These all are due to the presence of F127 and mr-HAP.

Selective Cellular Uptake and Cytotoxicity of Curcumin-encapsulated SPC and HSPC Liposome Nanoparticles on Human Bladder Cancer Cells.

BACKGROUND: Curcumin is a main bioactive constituent of turmeric (Curcuma longa L.) with pleiotropic health beneficial effects. However, poor bioavailability is the major barrier to the efficient pharmacological effects of curcumin in humans. AIMS: The present study aimed to develop liposome formulations based on soybean phosphatidylcholine (SPC) and hydrogenated SPC (HSPC) to enhance the bioavailability of curcumin in bladder cancer cells. METHODS: Curcumin was encapsulated in HSPC and SPC liposome nanoparticles using the solvent evaporation method. Physical properties, encapsulation efficiency (%), stability, and in vitro drug release of the prepared liposome formulations have been evaluated. The cellular uptake and cytotoxicity of curcumin-encapsulated nanoliposomes on bladder carcinoma HTB9 cell line and normal fibroblast L929 cell line were studied. DNA fragmentation, apoptosis, and genotoxicity assessments have been carried out to determine the molecular mechanisms underlying the cytotoxic effects of liposomal curcumin formulations on bladder cancer cells. RESULTS: The results indicated that curcumin could be efficiently encapsulated in the HSPC and SPC liposome formulations. The liposomal curcumin formulations have shown shelf-life stability for 14 weeks at 4°C. The accelerated stability testing showed that curcumin encapsulated in nanoliposomes was significantly (p < 0.001) more stable than free curcumin at various pH degrees ranging from alkaline to acidic pH. The in vitro drug release study showed curcumin to be sustainably released from the liposome nanoparticles. Of note, SPC and HSPC nanoliposome formulations significantly increased the cellular uptake and cytotoxicity of curcumin on bladder cancer HTB9 cells. Mechanistically, liposomal curcumin was found to exert a selective inhibitory effect on the viability of cancer cells by inducing apoptosis and DNA damage. CONCLUSION: In conclusion, SPC and HSPC liposome nanoparticles can significantly increase the stability and bioavailability of curcumin, which are important for improving its pharmacological effect.

High-efficient synthesis of carbon quantum dots from orange pericarp as fluorescence turn-on probes for Ca2+ and Zn2+ ion detection and their application in trypsin activity characterization.

Objectives: In this work, we propose an efficient preparation process for the synthesis of natural carbon quantum dots (NCQDs) by the usage of orange pericarp as the carbon natural resource, which is performed through hydrothermal treatment and top-down approaches. Materials and Methods: The structural, morphological, average size, and optical properties of synthesized NCQDs were investigated via dynamic light scattering (DLS), transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), atomic force microscopy (AFM), field emission scanning electron microscope (FESEM), energy dispersive x-ray spectroscopy (EDX), ultraviolet-visible spectroscopy (UV-Vis), and fluorescence PL spectra. Results: The shape of obtained NCQDs was observed to be spherical in the results of TEM analysis with an average size of 6-7 nm which confirms NCQDs essence. The signs of a strong peak (absorption) at around 282 nm throughout the UV-vis spectrum have been detected. The provided FTIR spectroscopy confirmed the existence of functional groups above the NCQDs surface. Furthermore, the surface charge of -11 mV through the obtained zeta potential regarding the synthesized NCQDs has been identified. MTT assay on mouse colon carcinoma cells (C26) demonstrated the lack of any signs of toxicity in NCQDs. Conclusion: The obtained NCQDs contain high photo-stability, excellent PL activity, and efficient fluorescent emission based on excitation. The results of kinetic studies revealed the ability of NCQDs to inhibit trypsin activity in a non-competitive model, which qualifies them as potent inhibitors and quenchers of trypsin. It can be suggested that the synthesized NCQDs have the potential of functioning as a sustainable and eco-friendly source for various applications such as sensors for detecting Ca2+ and Zn2+ and trypsin biosensor for determining enzyme activity.

An overview of polyallylamine applications in gene delivery.

A chief objective of gene transportation studies is to manipulate clinically accepted carriers that can be utilized to combat incurable diseases. Despite various strategies, efficiency and application of these vectors have been hindered, owing to different obstacles. Polyallylamine (PAA) is a synthetic water-soluble, weak base cationic polymer with different properties that could be administrated as an ideal candidate for biomedical applications such as gene delivery, drug delivery, or even tissue engineering. However, some intrinsic properties of this polymer limit its application. The two associated problems with the use of PAA in gene delivery are low transfection efficiency (because of low buffering capacity) and cytotoxic effects attributed to intense cationic character. Most of the strategies for structural modification of the PAA structure have focused on introducing hydrophobic groups to the polymeric backbone that target both cytotoxicity and transfection. In this perspective, we concentrate on PAA as a gene delivery vehicle and the existing approaches for modification of this cationic polymer to give insight to researchers for exploitation of PAA as an efficient carrier in biomedical applications.

Iranian Journal of Basic Medical Sciences, comparison of the three recent years.

Objectives: Melatonin, an important hormone secreted by the epiphysis, is a powerful anti-oxidant with a high potential to neutralize medical toxins. The goal of this study was to demonstrate the beneficial effect of melatonin on epididymal sperm and reproductive parameters in mice treated with acetylsalicylic acid (ASA). Materials and Methods: Male adult mice were divided into four treatment groups: control, ASA, melatonin, and ASA+melatonin. Mice were administered ASA (50 mg/kg, orally) and/or melatonin (10 mg/kg, intraperitoneally), or vehicle control, for 14 days. Sperm count, sperm motility, and sperm morphology were evaluated to assess fertility. A colorimetric assay was used to measure serum total antioxidant capacity (TAC). A sperm chromatin dispersion (SCD) test was used to assess sperm chromatin integrity. Sex hormone levels were measured by ELISA. Results: Compared to the control group, ASA treatment resulted in a significant decrease in sperm parameters (P<0.05), as well as a decrease in the integrity of sperm chromatin (P<0.01). ASA treatment also reduced serum testosterone and TAC levels (P<0.05). Co-administration of melatonin with ASA significantly improved epididymal sperm parameters and increased serum testosterone and TAC levels compared to the ASA-treated group. LH level was not different in the combined treatment group compared to control or ASA treatment. Conclusion: Short-term administration of ASA (50 mg/kg) has adverse effects on male reproductive function in mice. Co-administration of melatonin protects against ASA-induced impairment of male reproductive function by preventing the reduction in serum TAC and testosterone levels seen with ASA treatment alone.

Development of targeted gene delivery system based on liposome and PAMAM dendrimer functionalized with hyaluronic acid and TAT peptide: In vitro and in vivo studies.

The development of gene delivery systems is essential to improve their transfection efficiency and cytotoxicity. Combination of lipid and polymeric nanoparticles with the characteristics of both systems have been considered as a next-generation gene delivery platform. In the current study, we designed a novel and efficient targeted gene delivery system based on liposome and PAMAM dendrimer in cancer cells. Two polymeric formulations containing polyamidoamine-TAT (PAMAM-TAT) and PAMAM-TAT-Hyaluronic acid (HA) and two lipopolymeric carriers including PAMAM-TAT-Liposome and PAMAM-TAT-HA-Liposome were complexed with the enhanced green fluorescent protein (EGFP) plasmid and then evaluated in terms of physicochemical characteristics. The cytotoxicity and transfection efficiency of these synthetized carriers were accomplished against murine colon carcinoma cell line (C26). The biodistribution of polyplexes and lipoployplexes was also evaluated in the C26 tumor bearing mice. The results showed no significant toxicity for all designed nanoparticles (NPs) in C/P4. The highest gene expression was observed using lipopolyplex PAMAM-TAT-HA-Liposome in C/P4 (ratio polymer/DNA; wt/wt). Biodistribution study demonstrated more aggregation of targeted lipopolyplex in tumor cells than other nanoparticles (NPs). It could be concluded that the developed targeted lipopolymeric complex could serve as promising nanotherapeutic system for gene therapy.

PEGylated solid lipid nanoparticles functionalized by aptamer for targeted delivery of docetaxel in mice bearing C26 tumor.

OBJECTIVE: Colorectal cancer is one of the most deadly cancers in the world. Docetaxel (DTX) is a potentially important chemotherapeutic agent for the treatment of cancer. Many studies have attempted to improve its bioavailability and efficiency using different nanoparticulate drug delivery systems. SIGNIFICANCE: In the current study, PEGylated solid lipid nanoparticles (SLNs) containing DTX were prepared and modified with AS1411 anti-nucleolin aptamers to target nucleoin receptors on colorectal cancer cells. METHODS: Nanoparticles were characterized and the morphology was evaluated. In vitro studies were investigated on murine colon carcinoma (C26) and Chinese hamster ovary (CHO) cell lines. Then in vivo antitumor efficacy and survival analysis were evaluated in mice bearing the C26 tumor model. RESULTS: Results showed 135-140 nm particle size and about 78% DTX entrapment efficiency for actively targeted samples. PEGylated and aptamer-targeted SLNs containing DTX had the lowest IC50 (0.28 and 0.11 nM for 3 and 6 h incubation respectively) and higher cellular uptake values in the C26 cell line. Also in vivo results demonstrated that PEGylated and aptamer-targeted SLNs containing Docetaxel (Apt-PEG-SLN-DTX) improved antitumor activity and inhibited tumor growth in C26 tumor-bearing mice. CONCLUSION: These results suggested that PEGylated and aptamer-targeted SLNs containing DTX exhibited efficient characteristics in tumor inhibitory against murine C26 carcinoma model.

Bromelain Loaded Lipid-Polymer Hybrid Nanoparticles for Oral Delivery: Formulation and Characterization.

Bromelain (Br), a mixture of proteolytic enzymes from pineapple (Ananas comosus), has various therapeutic potentials; however, its low bioavailability has limited the clinical applications specifically in oral delivery as the most common convenient used route of administration. In the present study, a lipopolymeric nanoparticle (NP) containing Br was developed to enhance its stability and oral delivery efficiency. Firstly, Br was loaded into poly (D, L-lactide-co-glycolide acid) (PLGA) and PLGA-phosphatidylcholine (PLGA-PC) NPs using double emulsion solvent evaporation technique. Then, Br integrity and activity were investigated using SDS-PAGE and gelatin test. The stability and release profile of Br from synthetized NPs were evaluated at different pH values of the digestive system. Furthermore, cytotoxicity, cellular uptake, and the amount of Br passage from Caco-2 cells were explored. The results showed PLGA-PC-Br NPs had higher encapsulation efficiency (83%) compared to PLGA-Br NPs (50%). In addition, this NP showed more Br released in neutral (20.36%) and acidic (34%) environments compared to PLGA-Br NPs after 5 days. The delay in the release of Br from PLGA-PC-Br NPs versus the faster release of Br from PLGA-Br formulation could assure that an appropriate concentration of Br has reached the intestine. Intestinal absorption study demonstrated that lipid polymer NPs were able to pass through Caco-2 cells about 1.5 times more (98.4%) than polymeric NPs (70%). In conclusion, PLGA-PC NPs would be considered as a promising lipid-polymer nanocarrier for effective intestinal absorption of Br.

Hybrid in situ- forming injectable hydrogels for local cancer therapy.

Injectable in situ forming hydrogels are amongst the efficient local drug delivery systems for cancer therapy. Providing a 3D hydrogel network within the target tissue capable of sustained release of the chemotherapeutics made them attractive candidates for increasing the therapeutic index. Remarkable swelling properties, mechanical strength, biocompatibility, wide composition variety and tunable polymeric moieties have led to preparation of injectable hydrogels which also could be used as cavity adaptive chemotherapeutic-loaded implants to prevent post -surgical cancer recurrence. Implementation of various polymers, nanoparticles, peptide and proteins and different crosslinking chemistry facilitated the fabrication of hybrid hydrogels with favorable characteristics such as stimuli sensitive platforms or multifunctional systems. In the current review, we focused on design and fabrication strategies of injectable in situ forming hydrogels and summarized recent hybrid hydrogels used for local cancer therapy.

Dual Antibiotic and Diffusible Signal Factor Combination Nanoliposomes for Combating Staphylococcus epidermidis Biofilm.

Purpose: Microbial biofilms are one of the main causes of persistent human infections. Encapsulation of an antibiotic and a biofilm dispersal agent within a nano-carrier has been recognized as a novel approach to combat the problem of biofilm-related infections. Here, we develop the nanoliposomal formulation for delivery of vancomycin in combination with cis-2- decenoic acid (C2DA), to Staphylococcus epidermidis biofilm. The effects of the formulations were studied at two stages: biofilm growth inhabitation and biofilm eradication. Methods: Liposomal formulations were prepared by the solvent evaporation dehydration-rehydration method and were evaluated for size, zeta potential, and encapsulation efficacy. The ability of different agents in free and encapsulated forms were assessed to evaluate the anti-biofilm activities. Results: Vancomycin and C2DA were successfully co-encapsulated in the same nanoliposome (liposomal combination). The zeta potential values of the liposomal formulations of vancomycin, C2DA, and the liposomal combination were 37.2, 40.2, 51.5 mV, and the mean sizes of these liposomal formulations were 167.8±1.5, 215.5±8.8, 235.5±0.01, respectively. Encapsulation efficacy of C2DA was 65% and about 40% for vancomycin. The results indicated that liposomal combination exerted strong anti-biofilm activities, slightly exceeding those observed by the free form of a combination of vancomycin and C2DA, but higher than either agent used alone in their free forms. The anti-biofilm activity of formulations followed concentration and time-dependent manner. Conclusion: The combination of vancomycin and C2DA could inhibit biofilm formation. Employing the liposomal combination is a considerable method to remove bacterial biofilm.

Optimizing the synthesis and purification of MS2 virus like particles.

Introducing bacteriophage MS2 virus-like particles (VLPs) as gene and drug delivery tools increases the demand for optimizing their production and purification procedure. PEG precipitation method is used efficiently to purify VLPs, while the effects of pH and different electrolytes on the stability, size, and homogeneity of purified MS2 VLPs, and the encapsulated RNA sequences remained to be elucidated. In this regard, a vector, capable of producing VLP with an shRNA packed inside was prepared. The resulting VLPs in different buffers/solutions were assessed for their size, polydispersity index, and ability to protect the enclosed shRNA. We report that among Tris, HEPES, and PBS, with or without NaNO3, and also NaNO3 alone in different pH and ionic concentrations, the 100 mM NaNO3-Tris buffer with pH:8 can be used as a new and optimal MS2 VLP production buffer, capable of inhibiting the VLPs aggregation. These VLPs show a size range of 27-30 nm and suitable homogeneity with minimum 12-month stability at 4 °C. Moreover, the resulting MS2 VLPs were highly efficient and stable for at least 48 h in conditions similar to in vivo. These features of MS2 VLPs produced in the newly introduced buffer make them an appropriate candidate for therapeutic agents' delivery.

The effect of RGD-targeted and non-targeted liposomal Galbanic acid on the therapeutic efficacy of pegylated liposomal doxorubicin: From liposomal preparation to in-vivo studies.

The anti-cancer therapeutic application of Galbanic acid (Gba) as a strong antiangiogenic sesquiterpene coumarin has been limited due to its low water solubility. This issue necessitates developing new liposomal formulations for the efficient delivery of Gba in vivo. In this study, various liposomal formulations were prepared by a thin-film hydration method, and Gba was incorporated into the liposomal bilayers, which consequently increased its release profile compared to formulations in our previous study prepared by remote loading methods. The most stable formulation with desired properties was selected and decorated with RGD peptide (cyclo [Arg-Gly-Asp-D-Tyr-Cys]) to target tumor vasculature actively. The fluorescently-labeled model liposomes showed that the targeting could improve the receptor-mediated endocytosis of the liposomes higher than those prepared in our previous study in vitro in human umbilical vein endothelial cells (HUVECs), which was confirmed by chicken chorioallantoic membrane angiogenesis (CAM) model in vivo. Although not significant, it also could increase the accumulation of liposomes in colon tumors. In BALB/c mice bearing colon cancer, not only non-targeted Gba liposomes but also even RGD-targeted ones combinatorial therapy with pegylated liposomal doxorubicin could improve the anti-tumor efficacy as compared to their monotherapy. These outcomes have strong consequences for cancer therapy.

The Effect of Hydro-alcoholic Extract of Rheum Turkestanicum Roots against Oxidative Stress in Endothelial Cells.

INTRODUCTION: Cardiovascular disorders (CVD) are a common cause of mortality worldwide. Oxidative stress is thought to be a major factor leading to CVD. Anti-oxidants such as medicinal plants may have a role in the mitigation of vascular problems through free radicals scavenging. In this study, we evaluated the protective effects of Rheum turkestanicum against hydrogen peroxide (H2O2)-induced toxicity in endothelial cells (BAE-1). METHODS: To evaluate the protective effect of R. turkestanicum against H2O2 toxicity, four groups comprised of control group (the cells without any treatment), H2O2 group (the cells incubated with H2O2 (200 µM)), and treatment groups (the cells treated with R. turkestanicum (12200 µg/ml) alone or 24h before exposure to H2O2). Quercetin (30.23 µg/ml) was used as a bioactive ingredient of the extract. Then the cell viability, reactive oxygen species, lipid peroxidation, and apoptosis were evaluated. RESULTS: H2O2 exposure reduced cell viability to 13.6 ± 1.6%, enhanced ROS generation to 1445 ± 80.7%, lipid peroxidation (LPO, 290 ± 13% of control), and apoptotic cells (P < 0.001). In contrast, compared with H2O2 group, R. turkestanicum and quercetin significantly restored the cell viability to 80.3 ± 1.6 and 87.2 ± 2.1%, ROS formation to 186 ± 10 and 129 ± 1%, as well as LPO to 130.7 ± 7.7 and 116 ± 2.5 of control, respectively (P < 0.001). Therefore, the extract reduced H2O2-induced toxicity in BAE-1 cells by scavenging of free radicals. CONCLUSION: Our findings demonstrated that the extract might reduce toxicity of endothelial cells by attenuation of oxidative stress, which can be related to the presence of active ingredients including quercetin.

Preparation and in vivo evaluation of nanoliposomes containing vancomycin after intravitreal injection in albino rabbits.

OBJECTIVES: The in vivo efficacy of nanoliposomal formulation of vancomycin against methicillin-resistant Staphylococcus aureus (MRSA) assessed. MATERIALS AND METHODS: Nanoliposomal formulations were prepared and characterized. The in vivo study was carried out on rabbits which received liquid culture medium containing MRSA under anesthesia. After 48 hr, the eyes treated with the liposomal and free form of vancomycin. The rabbits were euthanized at predesignate intervals at 12, 24, 48, 96, 144 hr intervals injection. The antibacterial activity of different vancomycin formulations was assayed by the time killing method. RESULTS: The zeta potential, mean sizes and encapsulation efficacy of liposomal vancomycin were 29.7 mV, 381.93±30.13 nm and 47%, respectively. The results of time-killing studies indicated that the liposomal formula was more effective than the free form of vancomycin. CONCLUSION: The results of this study revealed that liposomal vancomycin formulation is a powerful nano-antibacterial agent to combat infectious endophthalmitis.