Efficient lung-targeted delivery of risedronate sodium/vitamin D3 conjugated PAMAM-G5 dendrimers for managing osteoporosis: Pharmacodynamics, molecular pathways and metabolomics considerations.

AIMS: This study aims at formulating combined delivery of Risedronate sodium (RIS) and Vitamin D3 (VITD3) for augmented therapeutic outcome against osteoporosis (OP) using deep lung targeted PAMAM-G5-NH2 dendrimers to minimize RIS gastrointestinal side effects and enhance both drugs bioavailability through absorption from the alveoli directly to the blood. METHODS: RIS-PAMAM-G5-NH2, VITD3-PAMAM-G5-NH2, and RIS/VITD3-PAMAM-G5-NH2 were prepared and evaluated in vitro for particle size (PS), zeta potential (ZP), %loading efficiency (%LE), morphology and FTIR. The efficacy of the RIS/VITD3-PAMAM-G5-NH2 compared to oral RIS was evaluated in OP-induced rats by comparing serum calcium, phosphorus, and computed bone mineral density (BMD) pre- and post-treatment. Additionally, a comprehensive metabolomics and molecular pathways approach was applied to find serum potential biomarkers for diagnosis and to evaluate the efficacy of inhaled RIS/VITD3-PAMAM-G5-NH2. KEY FINDINGS: RIS/VITD3-PAMAM-G5-NH2 was successfully prepared with a %LE of 92.4 ± 6.7 % (RIS) and 83.2 ± 4.4 % (VIT-D3) and a PS of 252.8 ± 34.1 adequate deep lung delivery. RIS/VITD3-PAMAM-G5-NH2 inhalation therapy was able to restore serum calcium, phosphorus, and BMD close to normal levels after 21 days of treatment in OP-induced rats. The WNT-signalling pathway and changes in the metabolite levels recovered to approximately normal levels upon treatment. Moreover, histone acetylation of the WNT-1 gene and miR-148a-3p interference proved to play a role in the regulation of the WNT-signalling pathway during OP progression and treatment. SIGNIFICANCE: Pulmonary delivery of RIS/VITD3-PAMAM-G5-NH2 offers superior treatment for OP treatment compared to the oral route. Molecular and Metabolic pathways represents key indicators for OP diagnosis and progression.

Distinct Proteins in Protein Corona of Nanoparticles Represent a Promising Venue for Endogenous Targeting - Part I: In vitro Release and Intracellular Uptake Perspective.

INTRODUCTION: Protein corona (PC) deposition on nanoparticles (NPs) in biological systems contributes to a great extent to NPs' fates; their targeting potential, the interaction with different biological systems and the subsequent functions. PC - when properly tuned - can serve as a potential avenue for optimization of NPs' use in cancer therapy. METHODS: Poly-lactic co-glycolic acid (PLGA)-based NPs exhibiting different physicochemical properties were fabricated and characterized. The PC makeup of these NPs were qualitatively and quantitatively analyzed by Western blot and Bradford assay, respectively. The effect of PC on the release of NPs' cargos and the intracellular uptake into B16F10 melanoma cells has been studied. RESULTS: The composition of NPs (polymeric PLGA NPs vs lipid-polymer hybrid NPs) and the conjugation of an active targeting ligand (cRGDyk peptide) represented the major determinants of the PC makeup of NPs. The in vitro release of the loaded cargos from the NPs depended on the PC and the presence of serum proteins in the release medium. Higher cumulative release has been recorded in the presence of proteins in the case of peptide conjugated NPs, cNPs, while the unconjugated formulations, uNPs, showed an opposite pattern. NPs intracellular uptake studies revealed important roles of distinct serum and cellular proteins on the extent of NPs' accumulation in melanoma cells. For example, the abundance of vitronectin (VN) protein from serum has been positively related to the intracellular accumulation of the NPs. CONCLUSION: Careful engineering of nanocarriers can modulate the recruitment of some proteins suggesting a potential use for achieving endogenous targeting to overcome the current limitations of targeted delivery of chemotherapeutic agents.

Distinct Proteins in Protein Corona of Nanoparticles Represent a Promising Venue for Endogenous Targeting - Part II: In vitro and in vivo Kinetics Study.

INTRODUCTION: Nanoparticles (NPs), upon introduction to the biological systems, become wrapped by serum and cellular proteins constituting the protein corona (PC). This PC contributes largely to the NPs' interaction with the biological systems and their subsequent functions. On the one hand, PC can decrease the efficiency of targeting by directing the NPs to the reticuloendothelial system (RES) or by masking the active targeting moieties and decreasing their ability to bind to their target receptors. On the other hand, some components of PC have offered hopes for achieving endogenous targeting. METHODS: In this study, we aimed at the investigation of the role of the PC in determining the behavior of cRGDyk peptide-unconjugated and -conjugated NPs (uNPs and cNPs) exhibiting different physicochemical properties and their interaction with melanoma on in vitro and in vivo levels. Mathematical modeling has been utilized to understand the kinetics of the interaction of NPs with the tumor cells and different organs, respectively. RESULTS: Endocytosis and exocytosis were reported to occur simultaneously for the utilized NPs. The balance was largely dependent on the NPs' physicochemical properties and the role of the PC. In addition, distinct proteins present in the PC (illustrated in the results of the PC analysis in part I) have also determined the patterns of the NPs' distribution in different organs and tissues of the vascular system, the RES system and the target tumot tissue. Vitronectin (VN) was found to mediate higher accumulation in integrin receptor-expressing melanoma cells, while complement 3 protein (C3) and clusterin (CLU), as an opsonin and dysopsonin, respectively, regulated the balance between the RES uptake and blood circulation. DISCUSSION: PC, if properly modulated by tuning NPs' physicochemical properties, can serve as a potential venue for optimum utilization of NPs in cancer therapy.

A Naturally Derived Carrier for Photodynamic Treatment of Squamous Cell Carcinoma: In Vitro and In Vivo Models.

Photodynamic therapy (PDT) is a non-invasive treatment strategy that includes the combination of three components-a photosensitizer, a light source, and tissue oxygen. PDT can be used for the treatment of skin diseases such as squamous cell carcinoma. The photosensitizer used in this study is the naturally derived chlorophyll derivative chlorin e6 (Ce6), which was encapsulated in ultradeformable ethosomes. Singlet oxygen production by Ce6 upon laser light irradiation was not significantly affected by encapsulation into ethosomes. PDT of squamous cell carcinoma cells treated with Ce6 ethosomes triggered increased mitochondrial superoxide levels and increased caspase 3/7 activity, resulting in concentration- and light-dose-dependent cytotoxicity. Ce6 ethosomes showed good penetration into 3D squamous cell carcinoma spheroids, which upon laser light irradiation exhibited reduced size, proliferation, and viability. The PDT effect of Ce6 ethosomes was specific and showed higher cytotoxicity against squamous cell carcinoma spheroids compared to normal skin fibroblast spheroids. In addition, PDT treatment of squamous cell carcinoma xenografts grown on chorioallantoic membranes of chick eggs (CAM) exhibited reduced expression of Ki-67 proliferation marker and increased terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) staining, indicating reduced proliferation and activation of apoptosis, respectively. The results demonstrate that Ce6-loaded ethosomes represent a convenient formulation for photodynamic treatment of squamous cell carcinoma.

Ethosomes and lipid-coated chitosan nanocarriers for skin delivery of a chlorophyll derivative: A potential treatment of squamous cell carcinoma by photodynamic therapy.

Photodynamic therapy (PDT) is a localized treatment strategy used for skin cancers such as squamous cell carcinoma (SCC), the second most common form of skin cancer. PDT combines a photosensitizer, laser source and tissue oxygen. In this study, the selected photosensitizer, ferrous chlorophyllin (Fe-CHL) was loaded in ethosomes and lipid coated chitosan (PC/CHI) nanocarriers to enhance skin delivery of Fe-CHL for potential PDT of squamous carcinoma. The nanocarrier formulations were characterized and studied for their skin retention and penetration depth of Fe-CHL across mouse skin ex vivo using high performance liquid chromatography and confocal microscopy. Confocal microscope images of mouse skin showed deeper penetration of ethosomes down to the dermis when compared to PC/CHI that was confined to the epidermis, although they showed no significant difference in skin retention. Immunohistochemistry (IHC) staining with ki67 and TUNEL show maintained skin structure and no cytotoxic effects of the nanocarrier gel formulations before laser exposure to mouse skin. The nanocarriers were also studied for their PDT effect against human SCC monolayer and three-dimensional (3-D) spheroids. When compared to ethosomes, PC/CHI showed higher cytotoxicity in MTT assay and live confocal microscopy showed cell disintegration after laser exposure. For 3-D spheroids, PC/CHI also showed higher cytotoxicity using acid phosphatase assay and a decrease in spheroid size was observed using light microscopy. In conclusion, both types of nanocarriers can be used for their potential treatment of SCC using PDT depending on the tumour localization in the skin.

Dermal delivery of Fe-chlorophyllin via ultradeformable nanovesicles for photodynamic therapy in melanoma animal model.

Melanoma is resistant to chemotherapeutics with poor prognosis and high potential of metastasis. Photodynamic therapy (PDT) represents a localized therapeutic modality, as cytotoxicity occurs when light activates photosensitizer (PS) at the tumour site. The aim of this study is dermal delivery of a high molecular weight hydrophilic photosensitizer (PS), ferrous chlorophyllin (Fe-CHL) via transethosomes for treatment of melanoma by PDT. Transethosomes were made of phosphatidyl choline, edge activator and 20% w/v Ethanol. They were evaluated for mean size, zeta potential, entrapment efficiency, ex-vivo permeation, localization in skin layers by transmission electron microscope (TEM), and finally, evaluated in melanoma animal model. Transethosomes of different mean vesicle size were evaluated for their skin retention and permeation through mice skin. TE of ∼500 nm (E3) being ultradeformable showed deep localization in skin confirmed by ex-vivo and TEM micrographs without permeation of PS to recipient compartment due to its size. The proposed study offers successful treatment of resistant melanoma by PDT, where complete tumour regression of small tumours occurred after single PDT, while large tumours after double PDT without recurrence for 8 months. This indicates the efficiency of nanovesicles in PS delivery and the efficiency of Fe-CHL in production of reactive oxygen species.

Targeted photodynamic-induced singlet oxygen production by peptide-conjugated biodegradable nanoparticles for treatment of skin melanoma.

BACKGROUND: Photodynamic therapy (PDT) has been determined to be a promising treatment modality in the most resistant tumors such as malignant melanoma. However, the key cytotoxic agent of PDT, -singlet oxygen (1O2) - represents a high risk of photodynamic-associated side effects e.g. skin photosensitization. Recently, controllable photosensitization, where 1O2 is produced on demand, has received increasing attention. In our study, this could be achieved via loading the photosensitizer (PS) in nanoparticles (NPs) decorated with target-specific moieties characterized by 1O2 quenching abilities to specifically locate the PS in the targeted cells and assure that 1O2 is only produced where desired after cellular processing. METHODS: Polymeric and hybrid lipid-polymer NPs were formulated and assayed for their physicochemical properties. This was followed by conjugation with an active targeting ligand, cRGDyk, cyclic (Arginine-Glycine-Aspartic acid-D-Tyrosine-Lysine) peptide. Finally, photodynamic potential of the selected formulations was assayed by quantification of 1O2 production and in vitro cytotoxicity. RESULTS: Three formulations were selected and nominated to be formulations of choice (FOCs); FOC-1 (200 nm, polymeric), FOC-2 (130 nm, polymeric) and FOC-3 (200 nm, hybrid). Physicochemical properties, most importantly particle size and NPs' composition have shown to be the major determinants in targeted NPs' 1O2 production and PDT-mediated cytotoxicity of melanoma. CONCLUSION: Proper selection of formulations intended for PDT application and target-specific ligands could achieve dual targeting; enhanced accumulation of NPs and protection of 1O2 production elsewhere other than target cells.

Role of 3-Acetyl-11-Keto-Beta-Boswellic Acid in Counteracting LPS-Induced Neuroinflammation via Modulation of miRNA-155.

Neuroinflammation is one of the most important mechanisms underlying neurodegeneration. Lipopolysaccharide (LPS) is a potent inflammogen which causes cognitive dysfunction. Boswellia serrata is known since many years as a powerful anti-inflammatory herbal drug. Its beneficial effect mainly arises from inhibition of 5-lipoxygenase (5-LO) enzyme. 3-acetyl-11-keto-ß-boswellic acid (AKBA) is the most potent 5-LO inhibitor extracted from the oleo-gum-resin of Boswellia serrata. The aim of the present work is to study the molecular mechanisms underlying the anti-inflammatory and neuroprotective effects of AKBA and dexamethasone (DEX) in LPS-induced neuroinflammatory model. A single intraperitoneal (i.p.) dose of LPS (0.8 mg/kg) was injected to induce cognitive dysfunction. The LPS-treated mice were administered for 7 days with either AKBA or DEX at intraperitoneal doses of 5 and 1 mg/kg, respectively. Cognitive, locomotor functions, and anxiety level were first examined. The level of the phosphorylated inhibitory protein for NF-κB, IκB-α (P-IκB-α), was measured, and the expression levels of the inflammatory microRNA-155 (miR-155) and its target gene, suppressor of cytokine signaling-1 (SOCS-1), were determined in the brain. Moreover, the level of carbonyl proteins as a measure of oxidative stress and several cytokines as well as markers for apoptosis and amyloidogenesis was detected. Results showed that AKBA and DEX reversed the behavioral dysfunction induced by LPS. AKBA decreased P-IκB-α, miRNA-155 expression level, and carbonyl protein content. It restored normal cytokine level and increased SOCS-1 expression level. It also showed anti-apoptotic and anti-amyloidogenic effects in LPS-injected mice. These findings suggest AKBA as a therapeutic drug for alleviating the symptoms of neuroinflammatory disorders.

An Investigation of the Sensing Capabilities of Magnetotactic Bacteria.

We investigate the sensing capabilities of magnetotactic bacteria (Magnetospirillum gryphiswaldense strain MSR1) to MCF-7 breast cancer cells. Cancer cells are allowed to grow inside a capillary tube with depth of 200 $\mu \mathrm {m}$ and motion of magnetotactic bacteria is investigated under the influence of oxygen gradient and geomagnetic field. The influence of cancer cells is modeled to predict the oxygen gradient within the capillary tube in three-dimensional space. Our experimental motion analysis and count of motile magnetotactic bacteria indicate that they migrate towards less-oxygenated regions within the vicinity of cancer cells. Bands of magnetotactic bacteria with average concentration of 18.8±2.0% are observed in close proximity to MCF-7 cells $(h = 20~ \mu \mathrm {m})$, whereas the concentration at proximity of $190~ \mu \mathrm {m}$ is 5.0 ± 6.8%.

Liposomal delivery of ferrous chlorophyllin: A novel third generation photosensitizer for in vitro PDT of melanoma.

BACKGROUND: Cutaneous melanoma (CM) has substantially increased among Caucasian populations in the past few decades. This increased the number of CM deaths throughout the world. Pigmentation of melanoma reduces the efficacy of photodynamic therapy (PDT). Third generation photosensitizers (PSs) are characterized by improved targeting to the diseased tissue and reduced systemic side effects. This study is directed towards synthesis and characterization of liposomes encapsulating sodium ferrous chlorophyllin (Fe-CHL) and assessing its efficacy as a PS in PDT of melanoma. METHODS: Phenylthiourea (PTU) was used as a melanin synthesis inhibitor. PDT has been applied on de-pigmented melanoma cells using liposomes-encapsulated Fe-CHL. Cell death mechanisms after PDT were evaluated. RESULTS: Treatment of melanoma cells with 200µM of PTU for 48h provided 49.9% melanin inhibition without significant cytotoxicity. Transmission electron microscope (TEM) results proved an increase in the cellular uptake of liposomes by increasing incubation period from 6 to 24h via endocytosis with preferential accumulation in the mitochondria and the nucleus. Following de-pigmentation, PDT was applied resulting in LC50 of 18.20 and 1.77µM after 24 and 48h incubation with liposomes-encapsulated Fe-CHL respectively and exposure to 56.2J/cm2 monochromatic red laser of wavelength of 652nm. Mechanism of cell death of Fe-CHL mediated PDT was found to be a combination of both apoptosis and necrosis. CONCLUSIONS: Liposomes could be efficiently employed as a potential sustained release delivery system in the Fe-CHL-mediated PDT of de-pigmented melanoma.

Synthesis and cytotoxic activities of some pyrazoline derivatives bearing phenyl pyridazine core as new apoptosis inducers.

The cyclization of chalcones 3a-3u with 3-hydrazinyl-6-phenylpyridazine 7 under basic condition led to the formation of new pyrazoline derivatives 8a-8u. All final compounds were characterized by spectral and elemental analyses. They were screened for their antiproliferative activities against A549 (lung), HepG-2 (liver), CaCo-2 (intestinal) and MCF-7 (breast) cancer cell lines. Some of the synthesized compounds exhibited promising antiproliferative activities especially compound 8k with IC50 values of 8.33, 1.67 and 10 µM against HepG-2, MCF-7 and CaCo-2 cancer cell lines, respectively. Moreover, their antiproliferative activity was due to apoptosis rather than necrosis induction except compound 8h which exhibited equal apoptotic and necrotic properties. Compound 8k showed 5 fold increase in caspase-3 activity indicating that the apoptosis proceeds via caspase-3 activation.

Optimization of radiation controlled gene expression by adenoviral vectors in vitro.

The radiation-inducible EGR-1-promoter has been used in different gene therapy approaches in order to enhance and locally restrict therapeutic efficacy. The aim of this study was to reduce nonspecific gene expression in the absence of irradiation (IR) in an adenoviral vector. Rat rhabdomyosarcoma R1H tumor cells were infected with adenoviral vectors expressing either EGFP or HSV-TK under control of the murine EGR-1 promoter/enhancer. Cells were irradiated at 0-6 Gy. Gene expression was determined by FACS-analysis (EGFP), or crystal violet staining (HSV-TK). The bovine growth hormone polyadenylation signal (BGH pA) was used as insulating sequence and was introduced upstream or upstream and downstream of the expression cassette. Infected R1H cells displayed IR dose-dependent EGFP expression. Cells treated with IR, AdEGR.TK and ganciclovir displayed a survival of 17.3% (6 Gy). However, significant gene expression was observed in the absence of IR with EGR.TK and EGR.EGFP constructs. Introduction of BGHpA upstream or upstream and downstream of expression cassette resulted in decreased nonspecific cytotoxicity by a factor of 1.6-2.3 with minor influence on the induced level of cytotoxicity. Introduction of insulating sequences in adenoviral vectors might allow tighter temporospatial control of gene expression by the radiation-inducible EGR-1 promoter.

Chlorophyll derivative mediated PDT versus methotrexate: an in vitro study using MCF-7 cells.

BACKGROUND: Breast cancer is the most common cause of cancer deaths among women worldwide. Although chemotherapy is a standard method for the treatment of breast cancer, the photodynamic therapy (PDT) is a recent promising modality for cancer diagnosis and treatment. Its major advantages over chemotherapy are better selectivity of tumour tissue destruction and lack of severe local and systemic complications. This work is directed towards evaluation of the efficacy of Photodynamic therapy using chlorophyll derivative (CHL) as a photosensitizer in treatment of breast cancer. It also aims at investigation of the genetic safety of chlorophyll mediated PDT in comparison to the conventional chemotherapy. METHODS: Both methotrexate (MTX) and light activated chlorophyll derivative were used to target MCF-7 breast cancer cell line. Standard karyotyping and alkaline single cell microgel electrophoresis assay (Comet assay) were applied on normal human peripheral blood lymphocytes (HPL) in order to investigate the respective possible mutagenic and genotoxic side effects that might result from application of each therapeutic modality. RESULTS: Results obtained from this study showed that 50% of MCF-7 tumour cell death (LC(50)) was reached by using a concentration of chlorophyll derivative that is 138 times lower than MTX. Moreover, chlorophyll derivative exerted no genetic side effects as compared to MTX that resulted into several types of chromosomal breakages. CONCLUSIONS: Compared to MTX, light activated chlorophyll derivative proved to be a better candidate for breast cancer cell toxicity, referring to its higher efficacy at tumour cells killing, safety to normal cells and simple method of extraction.

Skeletal muscle phenotypically converts and selectively inhibits metastatic cells in mice.

Skeletal muscle is rarely a site of malignant metastasis; the molecular and cellular basis for this rarity is not understood. We report that myogenic cells exert pronounced effects upon co-culture with metastatic melanoma (B16-F10) or carcinoma (LLC1) cells including conversion to the myogenic lineage in vitro and in vivo, as well as inhibition of melanin production in melanoma cells coupled with cytotoxic and cytostatic effects. No effect is seen with non-tumorigenic cells. Tumor suppression assays reveal that the muscle-mediated tumor suppressor effects do not generate resistant clones but function through the down-regulation of the transcription factor MiTF, a master regulator of melanocyte development and a melanoma oncogene. Our findings point to skeletal muscle as a source of therapeutic agents in the treatment of metastatic cancers.