Bioinformatics approach for prediction and analysis of the Non-Structural Protein 4B (NSP4B) of the Zika virus.

BACKGROUND: The Nonstructural Protein (NSP) 4B of Zika virus of 251 amino acids from (ZIKV/Human/POLG_ZIKVF) with accession number (A0A024B7W1), Induces the production of Endoplasmic Reticulum ER-derived membrane vesicles, which are the sites of viral replication. To understand the physical basis of how proteins fold in nature and to solve the challenge of protein structure prediction, Ab-initio and comparative modeling are crucial tools. RESULTS: The systematic in silico technique, ThreaDom, had only predicted one domain (4 - 190) of NSP4B. I-TASSER, and Alphafold were ranked as the best servers for full-length 3-D protein structure predictions of NSP4B, where the predicted models were evaluated quantitatively using benchmarked metrics including C-score (-3.43), TM-score (0.77949), RMSD (2.73), and Z-score (1.561). The functional and protein binding motifs were realized using motif databases, secondary and surface accessibility predictions combined with Post-Translational Modification Sites (PTMs) prediction. Two highly conserved protein-binding motifs (Flavi NS4B and Bacillus papRprotein), together with three (PTMs) (Casein Kinase II, Myristyl site, and ASN-Glycosylation site) were predicted utilizing the Motif scan and Scanprosite servers. These patterns and PTMs were associated with NSP4B's role in triggering the development of the viral replication complex and its participation in the localization of NS3 and NS5 on the membrane. Only one hit from Structural Classification of Protein (SCOP) matched the protein sequence at positions 10 to 397 and was categorized six-hairpin glycosidases superfamily according to CATH (Class, Architecture, Topology, and Homology). Integrating this NSP4B information with the templates' SCOP and CATH annotations achieves it easier to attribute structure-function/evolution links to both previously known and recently discovered protein structures.

Assessment of the therapeutic potential of lutein and beta-carotene nanodispersions in a rat model of fibromyalgia.

Fibromyalgia (FM) is a chronic disorder characterized by widespread musculoskeletal pain, fatigue, and cognitive impairment. Despite the availability of various treatment options, FM remains a challenging condition to manage. In the present study, we investigated the efficacy of formulated nanodispersions of lutein and beta-carotene in treating FM-related symptoms induced by reserpine in female Wistar rats. Several techniques have been implemented to assess this efficacy at various levels, including biochemical, bioelectrical, and behavioral. Namely, oxidative stress markers, monoamine levels, electrocorticography, pain threshold test, and open field test were conducted on control, FM-induced, and FM-treated groups of animals. Our results provided compelling evidence for the efficacy of carotenoid nanodispersions in treating FM-related symptoms. Specifically, we found that the dual action of the nanodispersion, as both antioxidant and antidepressant, accounted for their beneficial effects in treating FM. With further investigation, nano-carotenoids and particularly nano-lutein could potentially become an effective alternative treatment for patients with FM who do not respond to current treatment options.

Liposomal IL-22 ameliorates liver fibrosis through miR-let7a/STAT3 signaling in mice.

The therapeutic effect of liposomal IL-22 versus non-liposomal IL-22 on liver fibrosis was investigated. IL-22 (5 µg/ml) was incorporated into negative charged liposomes. Schistosoma mansoni infected mice were treated with liposomal IL-22 for either 7 or 14 days before decapitation. Liver and spleen were removed and splenocytes were isolated for in vitro investigations. TNF-α, IL-17, IL-22 and IgE levels were assessed. Hepatic granulomas were counted, granuloma index and its developmental stages were calculated. Hepatic expressions of STAT3, ß-catenin and let-7a miRNA were evaluated. Liposomal IL-22 size was clustered around 425.9 ± 58.0 nm with negative zeta potential (-18.8 ± 1.3 mV). After 14 days, 65.5% of IL-22 was released from liposomal IL-22 as was gradually observed in vitro. Liposomal IL-22 significantly (p < 0.05) decreased IL-17 level (-33.1%) of healthy splenocytes compared to non-liposomal IL-22. In vivo therapeutic effect of liposomal IL-22 revealed a significant (p < 0.05) decrease in hepatic granuloma index (-22.1%) and levels of TNF-α (-49.2%) and IL-17 (-57.3%), but a marked increase in IL-22 (64.2%) and IgE (196.1%) levels comparing to non-liposomal IL-22. Three developmental stages of hepatic granuloma (NE, EP, and P) were observed in liposomal and non-liposomal IL-22 groups (79.6 ± 1.7 and 81.8 ± 8.7, respectively, P < 0.05), with higher relative frequency of EP stage. Additionally, liposomal IL-22 treatment increased hepatic expression of STAT3 (21.7 fold change) and let-7a (3.6 fold change) and reduced ß-catenin expression (0.6 fold change) compared to healthy mice. Conclusively, liposomal IL-22 seems more effective in the treatment of liver fibrosis resulting from S. mansoni infection than non-liposomal IL-22.

Evaluation of the antineoplastic property of prodigiosins and 5-fluorouracil in restraining the growth of Ehrlich solid tumors in mice.

Prodigiosins have been shown to have anticancer activities. 5-Fluorouracil (5-FU) is broadly used chemotherapeutic drug that treats different solid tumors including breast cancer but has low response rates and a variety of side effects. In this study, we evaluated the anticancer properties of prodigiosins in a murine model "Ehrlich tumor" and tested whether it can be added to 5-FU to potentiate its effects. Markers of oxidative stress; MDA, NO, and GSH levels were evaluated as well as antioxidant enzyme activities of CAT SOD, GR, and GPx. The levels of Bax, Bcl-2, PCNA, and NF-κB proteins were measured using ELISA kits. The mRNAs of p53 and Cdc2 and Casp3 were quantitatively measured by real-time PCR and ELISA respectively. Cell cycle analysis was performed using flow cytometery. Prodigiosins did not influence tumor volume. Prodigiosins have not induced oxidative stress while 5-FU did increase MDA, NO but decreased GSH levels. The combination prodigiosins and 5-FU did reduce oxidative stress markers; MDA, NO and increased GSH levels. Prodigiosins significantly increased CAT only while 5-FU did decreased SOD, CAT, GPx, and GR. The combination prodigiosins and 5-FU increased the levels of these enzymes again. Prodigiosins increased the Bax/Bcl-2 ratio while the combination deceased it. In conclusion, prodigiosins have pronounced anticancer properties but their combination with 5-FU decreased oxidative stress exerted by 5-FU but weakened the apoptotic effects of 5-FU. Prodigiosins could affect a key mechanism through which 5-FU exerts its tumor inhibitory effects.

Radiation and chemotherapy variable response induced by tumor cell hypoxia: impact of radiation dose, anticancer drug, and type of cancer.

Hypoxia is a condition in which proliferating tumor cells are deprived of oxygen due to limited blood supply from abnormal tumor microvasculature. This study aimed to investigate the molecular changes that occur in tumor cell hypoxia with special emphasis placed on the efficacy of chemotherapeutic and radiation-related effects. Four commercially available chemotherapeutic agents: cisplatin, cyclophosphamide, doxorubicin, and 5-fluorouracil, were tested for their cytotoxic activity on the cancer cell lines PC3 (prostate), HepG2 (liver), and MCF-7 (breast). Tumor cell lines under hypoxia were treated with both IC50 concentrations of the different chemotherapeutic agents and irradiated with 5 and 10 Gy using a 137Cs gamma source. Hypoxia-inducible factor-1α (HIF-1α) protein levels were examined using an ELISA assay. Hypoxic cells showed a significant change in cell viability to all chemotherapeutic agents in comparison to normoxic controls. HepG2 cells were more resistant to the cytotoxic drug doxorubicin compared to other cancer cell lines. The flow cytometric analysis showed that hypoxic cells have lower levels of total apoptotic cell populations (early and late apoptosis) compared to normoxic cells suggesting decreased hypoxia-induced apoptosis in cancer cells. The highest reduction in HIF-1α level was observed in the MCF-7 cell line (95.5%) in response to the doxorubicin treatment combined with 10 Gy irradiation of cells. Chemoradiotherapy could result in minimal as well as a high reduction of HIF-1α based on cell type, type of chemotherapy, and amount of ionizing radiation. This study highlights future research work to optimize a combined chemoradiotherapeutic regime in individual cancer cell hypoxia.

Computational Approach for Probing Redox Potential for Iron-Sulfur Clusters in Photosystem I.

Photosystem I is a light-driven electron transfer device. Available X-ray crystal structure from Thermosynechococcus elongatus showed that electron transfer pathways consist of two nearly symmetric branches of cofactors converging at the first iron-sulfur cluster FX, which is followed by two terminal iron-sulfur clusters FA and FB. Experiments have shown that FX has lower oxidation potential than FA and FB, which facilitates the electron transfer reaction. Here, we use density functional theory and Multi-Conformer Continuum Electrostatics to explain the differences in the midpoint Em potentials of the FX, FA and FB clusters. Our calculations show that FX has the lowest oxidation potential compared to FA and FB due to strong pairwise electrostatic interactions with surrounding residues. These interactions are shown to be dominated by the bridging sulfurs and cysteine ligands, which may be attributed to the shorter average bond distances between the oxidized Fe ion and ligating sulfurs for FX compared to FA and FB. Moreover, the electrostatic repulsion between the 4Fe-4S clusters and the positive potential of the backbone atoms is lowest for FX compared to both FA and FB. These results agree with the experimental measurements from the redox titrations of low-temperature EPR signals and of room temperature recombination kinetics.

The anti-HCV, Sofosbuvir, versus the anti-EBOV Remdesivir against SARS-CoV-2 RNA dependent RNA polymerase in silico.

Coronavirus diseases 2019 (COVID-19) are seriously affecting human health all over the world. Nucleotide inhibitors have promising results in terms of its efficacy against different viral polymerases. In this study, detailed molecular docking and dynamics simulations are used to evaluate the binding affinity of a clinically approved drug, sofosbuvir, with the solved structure of the viral protein RNA-dependent RNA polymerase (RdRp) and compare it to the clinically approved drug, Remdesivir. These drugs are docked onto the three-dimensional structure of the nsp12 protein of SARS-CoV-2, which controls the polymerization process. Hence, it is considered one of the primary therapeutic targets for coronaviruses. Sofosbuvir is a drug that is currently used for HCV treatment; therefore, HCV RdRp is used as a positive control protein target. The protein dynamics are simulated for 100 ns, while the binding is tested during different dynamics states of the SARS-CoV-2 RdRp. Additionally, the drug-protein complexes are further simulated for 20 ns to explore the binding mechanism. The interaction of SARS-CoV-2 RdRp as a target with the active form of sofosbuvir as a ligand demonstrates binding effectiveness. One of the FDA-approved antiviral drugs, such as sofosbuvir, can help us in this mission, aiming to limit the danger of COVID-19. Sofosbuvir was found to bind nsp12 with comparable binding energies to that of Remdesivir, which has been reported for its potential against COVID-19 RdRp and is currently approved by the FDA.

Stress impact of liposomes loaded with ciprofloxacin on the expression level of MepA and NorB efflux pumps of methicillin-resistant Staphylococcus aureus.

One mechanism of ciprofloxacin resistance is attributed to chromosomal DNA-encoded efflux pumps such as the MepA and NorB proteins. The goal of this research is to find a way to bypass Staphylococcus aureus' efflux pumps. Because of its high membrane permeability and low association with NorB and MepA efflux proteins, a liposome-encapsulating antibiotic is one of the promising, cost-effective drug carriers and coating mechanisms for overcoming active transport of methicillin-resistant S. aureus (MRSA) multidrug-resistant efflux protein . The calculated "Log Perm RRCK" membrane permeability values of 1,2-distearoyl-sn-glycerol-3-phosphocholine (DSPC) ciprofloxacin liposome-encapsulated (CFL) showed a lower negative value of - 4,652 cm/s and greater membrane permeability than ciprofloxacin free (CPF). The results of RT-qPCR showed that cationic liposomes containing ciprofloxacin in liposome-encapsulated form (CFL) improved CPF antibacterial activity and affinity for negatively charged bacterial cell surface membrane in comparison to free drug and liposome, as it overcame several resistance mechanisms and reduced the expression of efflux pumps. Ciprofloxacin liposome-encapsulated (CFL) is therefore more effective than ciprofloxacin alone. Liposomes can be combined with a variety of drugs that interact with bacterial cell efflux pumps to maintain high sustained levels of antibiotics in bacterial cells.

Enhanced cytotoxic activity of beta carotene conjugated liposomes towards breast cancer cell line: comparative studies with cyclophosphamide.

This work aims to evaluate cyclophosphamide (Cyclo) cytotoxic efficacy combined with liposomes in the presence or absence of beta carotene (beta) by detecting the effects of these compounds on the breast cancer cell line (MCF-7) DNA damage. The IC50 value for beta in cytotoxic assay with MCF-7 treated cells was 21.15 µg/ml, while with liposomal beta (LipoBeta) being 121 µg/ml. The free Cyclo IC50 value was 719.86 µg/ml, its liposomal form (LipoCyclo) was 172 µg/ml. The results indicated that in contrast with Cyclo and control values, all comet assay parameters for the LipoBeta were significantly increased (P < 0.05). In MCF-7 cells treated with beta, the findings show a higher intensity of comet tail than those treated with LipoBeta. The presence of several double-strand breaks suggests this high intensity relative to the head. The molecular combination between Cyclo and liposomes in the presence or absence of beta was characterized. Dynamic light scattering measurements confirmed the mono-dispersity of all samples. The incorporation of Cyclo or beta into liposomes exhibited a slight shift to higher temperature compared to the main peak of empty liposomes that exists at 101.5°C which creates a conformational disorder within the phospholipids. The FTIR study showed structural alterations in vesicles after liposome encapsulation.

Cationic liposome-encapsulated carotenoids as a potential treatment for fibromyalgia in an animal model.

The present study investigated the efficacy of cationic liposome-encapsulated carotenoids (lutein or beta-carotene) as a treatment in an animal model of fibromyalgia (FM). Preparation and characterization of the nano-sized cationic liposomal carotenoids have been carried out. FM has been induced in the experimental animals via successive subcutaneous reserpine injection (1 mg/kg). Animals were divided into four groups; control, reserpinized (Res), reserpinized and cationic liposomal lutein-treated (Res + CL-Lut), and reserpinized and liposomal beta-carotene-treated (Res + CL-Bc). Levels of norepinephrine (NE), dopamine (DA), and serotonin (5-HT), and oxidative stress markers (MDA, H2O2, NO, and GSH) were determined in the brain's cortical tissue of the different groups of animals. Furthermore, the spectral analysis of the electrocorticogram (ECoG) was carried out. Animal behavior was tested for different animal groups. Results showed a significant reduction in monoamines, an elevation of oxidative stress markers, a shift in the ECoG frequency band power, and a change in pain threshold of the reserpinized animals. A return to a non-significant difference from the control values of all the measured parameters has been obtained after two weeks of cationic liposomal carotenoid preparations treatment. The present findings shed more light on the validity of the reserpine model of FM and provide evidence for the antidepressant, antioxidant, and anti-nociceptive potential of the cationic liposomal carotenoids. The present results proofed that the natural product preparations on a nano-sized scale could be a good alternative to the pharmacological interventions for FM treatment.

A multicompartment vascular implant of electrospun wintergreen oil/ polycaprolactone fibers coated with poly(ethylene oxide).

BACKGROUND: The aim of the present study was to fabricate double layered scaffolds of electrospun polycaprolactone (PCL) and poly(ethylene oxide) (PEO). The electrospun PCL fibers were functionalized with wintergreen oil (WO) as a novel approach to prevent vascular grafts failure due to thrombosis by adjusting biomaterial-blood interactions. METHODS: PCL tubular scaffolds were prepared by electrospinning approach and coated with PEO as a hydrophilic polymer. The single and double layered scaffolds were characterized in terms of their morphological, chemical properties -as well as-hemocompatibility assays (i.e. prothrombin time, hemolysis percentage and platelets adhesion). Moreover, the antioxidant potential of WO-PCL samples were measured by 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) free radical assay. RESULTS: The results demonstrated that incorporation of WO during the electrospinning process decreased the PCL fiber diameter. In addition, the prothrombine time assay shows that WO could be used to lower the electrospun PCL fiber tendency to induce blood clotting. Moreover, SEM observations of platelets adhesion of both single and double layered PCL/PEO scaffolds fiber shows an increase of platelets number, compared with the scaffolds containing WO. CONCLUSIONS: The antioxidant potential and blood compatibility measurements of WO-PCL/PEO samples highlight the approach made so far as an ideal synthetic small size vascular grafts to overcome autogenous grafts shortages and drawbacks.

Preclinical Assessment of 99mTc-Labeled Liposome Agents as an Effective Tracer in Nuclear Medicine.

This study assessed the use of 99mTc-liposome agents for nuclear medicine purposes. Methods: A variety of 99mTc-liposome formulations were compared with common lymphoscintigraphic agents, including 99mTc-labeled regular sulfur colloid and 99mTc-labeled human serum albumin, besides assisting the use of positively charged liposomes in rabbits. Ten male rabbits (2-2.5 kg) were anesthetized with ketamine and xylazine intramuscularly. Then, they were injected with different 99mTc-liposome agents subcutaneously in the dorsum of each hind foot over the region of the metatarsals at the midline, as well as intravenously. Dynamic (1 min) scintigraphic γ-camera images were acquired in a 256 × 1,024 matrix both early and 60 min after injection. Afterward, the tissue biodistribution was determined by calculating the percentage injected dose per organ for each 99mTc agent and studying the heart-to-liver, heart-to-bone marrow, and heart-to-kidney ratios. Results: All agents demonstrated good migration from the injection site to the blood pool but not to lymphatic drainage. Agents were starting to clear out rapidly after 60 min. Conclusion: 99mTc-liposome imaging can be used to develop novel liposome compositions with improved cardiac diagnostic and drug delivery characteristics.

Biophysical characterization of lutein or beta carotene-loaded cationic liposomes.

The interactions between carotenoids and membrane constituents are vital for understanding the mechanism of their dynamic action. Lutein and beta-carotene were loaded separately into the bilayer of dipalmitoylphosphatidylcholine (DPPC) mixed at a molar ratio with l-α-phosphatidylethanolamine derived from sheep brain (cephalin) and stearylamine (SA) to form cationic liposomes. The molecular interaction between lutein or beta-carotene with cationic liposomes was studied using transmission electron microscopy (TEM), dynamic light scattering (DLS), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) spectroscopy. Encapsulation efficiency (EE %) and in vitro drug release were determined. The DLS measurements confirmed the mono-dispersity of all samples. TEM results revealed that liposomal samples were oval-shaped and there was a change in their morphology and size upon encapsulation of lutein or beta-carotene. Beta-carotene was observed to adhere to the boundary surface within the liposomal assembly with external morphological alterations. EE% of lutein and beta-carotene exceeded 98.8 ± 0.3% and 87 ± 4%, respectively. Lutein doped with cationic liposomes shows better in vitro release stability (about 30%) than beta-carotene (about 45%) between the 3rd and the 6th hour manifested by lower leakage rate percentage of lutein which would lead to higher lutein retention. The incorporated lutein resulted in broadening and shifting of the major endothermic peak of the co-liposomes, while the incorporation of beta-carotene did not induce a noticeable shift. An FTIR study was employed to reveal structure alterations in the vesicles after the encapsulation of lutein or beta-carotene into liposomes. Encapsulation of lutein or beta-carotene into liposomes induced a change in the frequency of the symmetric and asymmetric CH2 stretching bands in the acyl chain that may influence the order of the membrane.

Comparative study between lutein and its liposomal form on cisplatin-induced retinal injury in rabbits.

Aim: Lutein is a potent antioxidant that is found in ocular tissue. It protects retina against oxidative stress. We aimed to increase lutein efficiency by encapsulating it into liposome and testing its neuroprotective effect against cisplatin-induced retinal injury in rabbits. Materials and methods: Twenty-four male, New Zealand, rabbits weighing 1.5-2 kg were divided into four groups, as follows: group I as a control, group II received cisplatin, group III received free lutein + cisplatin and group IV received liposomal lutein + cisplatin. All treatments were administrated twice per week for 14 days. Electroretinogram (ERG) was recorded for all rabbits just before decapitation. Then, the retinae were subjected to histopathological evaluations and comet assay. Results: Results indicated significant decrease (p ˂ 0.01) in ERG waves, significant increase (p ˂ 0.01) in all parameters of comet assay (% tailed cells, tail length, DNA% in tail and tail moment), severe fragmentation in photoreceptors layer and changes in inner retina after the administration of cisplatin. There were some sort of improvement in ERG, comet assay and the histological results after the administration of lutein with cisplatin, whereas these tests yielded values comparable to control in the liposomal lutein group. Conclusions: Liposomal lutein administration could prevent the detrimental effects of cisplatin on the retina, while avoiding the use any artificial chemicals. The latter might be preferable but with possible highly toxic effects. Results were promising and worse further future investigations.

Radioprotective efficacy of Ginkgo biloba and Angelica archangelica extract against technetium-99m-sestamibi induced oxidative stress and lens injury in rats.

PURPOSE: Technetium-99m is a radioactive tracer that emits gamma rays. Its half-life time is 6 h. Similar to other ionizing radiations, the main mechanism of radiation-induced effects is initiated through the production of reactive oxygen species (ROS). This study was designed to determine the possible protective effects of Ginkgo biloba and Angelica archangelica against oxidative organ damage that was induced by 99mTc-sestamibi. MATERIALS AND METHODS: The experiments were performed on thirty-six Wistar-rats which were subdivided into control groups and groups exposed to 99mTc-sestamibi. The irradiated groups were either untreated or pre-treated with G. biloba or A. archangelica. For all groups, the levels and/or activities of Catalase (CAT), Glutathione (GSH), Malondialdehyde (MDA) and Superoxide-dismutase (SOD) were measured in blood and lenses. The soluble/insoluble protein ratio was determined and lens-protein profiles were obtained via Sodium-Dodecyl-Sulfate Polyacrylamide Gel-Electrophoresis (SDS-PAGE). RESULTS: There were no significant difference between the pre-treated and irradiated G. biloba group and control group, while both groups were significantly different (p < .05) from the untreated irradiated group. On the other hand, treatment with A. archangelica did not confer any significant protection against 99mTc-sestamibi induced toxicity. CONCLUSIONS: This study demonstrated that G. biloba, through its free radical scavenging and antioxidant properties, successfully attenuated 99mTc-sestamibi radiation-induced oxidative organ injury. The latter is a crucial factor of cataractogenesis in rats, suggesting that G. biloba may have a potential benefit in the protection against radiopharmaceuticals.

Assessment of DNA damage in Ehlrich carcinoma after treatment with doxorubicin encapsulated in nanoscales thermosensitive liposomes in combination with localized hyperthermia.

Nanoscales thermosensitive liposomes (TSL) composed of synthetic lipids (dipalmitoylphosphatidylcholine, and distearoylphosphatidylcholine), were used for doxorubicin encapsulation with 70% encapsulated efficiency. The liposomes were characterized by dynamic light scattering, transmission electron microscopy and turbidity method. Additionally, the liposomes exhibited a significant release of doxorubicin (Dox) by 60% within 5 min at 42°C. To assess the therapeutic efficacy of Dox in combination with hyperthermia, Dox free and encapsulated TSL were administered directly to Ehrlich tumor bearing mice at 1 mg/kg dose. Immediately after the drug administration, hyperthermia was applied to mention the temperature inside the tumor site at 42°C either for 5 min and 30 min. The results indicate a significant increase in the percent of apoptotic and necrotic cells in the treated group. Moreover, disrupts the integrity and the amount of intact DNA in tumor cells. In conclusion, Dox and hyperthermia may serve as a useful targeted drug delivery system for management of Ehrlich carcinoma.

Enhancement of the ocular therapeutic effect of prednisolone acetate by liposomal entrapment.

Eye drops account for 90% of ophthalmic formulations despite of the rapid precorneal drug loss. Our aim is to test the effect of positive charge induction and the subsequent size reduction on the efficiency of liposomes as ocular drug delivery system for the lipophilic drug prednisolone acetate (PSA). Different formulations of PSA-loaded liposomes, positive multilamellar liposomes (pMLV), positive small (nano-sized) unilamellar liposomes (pSUV) and neutral multilamellar liposomes (nMLV), were prepared. These formulations were characterized by measuring surface charge, size distribution, entrapment efficiency, release rate, and ability to deliver PSA across the cornea. In vitro studies showed that positive charge induction reduces the transcorneal flux (about 1.9-fold lower than nMLV), while the subsequent size reduction results in higher flux (about 1.2-fold higher than nMLV). But in vivo results revealed that pSUV produced more concentrations of PSA in aqueous humor than nMLV (P < 0.05) suggesting greater chance for drug penetration, pSUV were more effective than nMLV in this regard (P < 0.05). As revealed by in vivo studies and ophthalmic examinations, positive charge induction and the subsequent size reduction increased the efficiency of liposomes as ocular drug delivery system for PSA.