Earticle

Recent developments of effective skin-whitening agents have focused on melnogenesis inhibition followed by decreasing total melanin contents. Keratinocyte secretes stimulator of melanogenesis to neighboring melanocytes, providing protection against UV radiation. Keratinocytes also produce other cytokines, such as IL-1α, IL-6, TNF-α and TGF-β, which inhibits melanogenesis.1) In this study, inhibitory melanogenesis was investigated in melanoma cells treated with keratinocytes-cultured medium contains Angelica gigas extract. To decide the proper treatment concentration of extract, MTT assay was performed with Keratinocytes. Keratinocytes-cultured medium was collected 24h later, and immediately used to culture melanoma cells. 2D PAGE analysis was done for investigation of melanogenesis related proteins. Acknowledgements This research work was supported by a grant from the Engineering Research Center for Advanced Bioseparation Technology, KOSEF.

Propolis has well-known antimicrobial activity as well as antioxidant, antitumoral, antiinflammatory and regenerative properties, and it has characterized water-soluble. In this study, chitosan / cellulose acetate butylate microspheres with propolis were prepared by the method of water / oil / water (W/O/W) emulsion and had the size interval of 200–2809m. W/O/W emulsion has been prepared by stirring for 30min at room temperature. W/O/W emulsion was evaluated by SEM. The chitosan /cellulose acetate butylate microshperes with propolis was measured of loading efficiency by ultraviolet spectroscopy at 290nm and release of propolis in vitro and the release rate. The antioxidation activity assessed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The infrared spectrums of microspheres were recorded on an FT-IR. Furthermore, the propolis loaded microspheres were observed in vitro against bacteria such as Staphylococcus aureus, Staphylococcus epidermis. The results suggest that the microspheres can have important applications in the cosmetic and food industry.

Increased levels of reactive oxygen species (ROS) can damage various cellular processes. We examine the overall and nanoscale morphologies and mechanics of cytostructural elements of human skin cells during oxidative stress-induced skin damage. Human skin fibroblasts exposed to oxidizing agents were imaged with atomic force microscopy (AFM), and proteomic tools were used to clarify ROS signaling-responsive proteins. The cytoskeletal organization, morphology, oxidative stress, and viability were also marked at the following time points. Oxidative agents induced time- and concentration- dependent disruption of native organization of cytoskeleton with a decrease in cell integrity. These dynamic changes in cell mechanical elements were accompanied by roughness increase, morphological changes, increased oxidative stress, and loss of cell viability. A water-soluble derivative of vitamin E, Trolox, showed a preventive effect on the ROS-induced cellular damage. The results indicate that alterations of cellular constituents seem to activate the cell death cascade/apoptosis-related proteins. Furthermore, the oxidative damage to cytoskeleton might occur at relatively early stages of exposure.

Not only have mesenchymal stem cells (MSCs) multilineage potency, but also provide a supportive cellular microenvironment. The cellular capabilities of expansion and differentiation are known to be strongly affected by environment and media. For the serum-free cultivation of MSCs, the effect of serum-free conditioned media (CM) from mixed cells on the expansion of bone marrow (BM)-MSCs was investigated. We substituted fetal bovine serum (FBS) by serum-free media (SFM) for the elimination of possible contaminations and provided CM for their microenvironments. The mixed cells were composed of umbilical cord blood-MSCs, BM-MSCs, periosteum-derived progenitor cells and fibroblasts. Cell viability, growth kinetics and MSCs specific surface makers were compared between serum-free CM and culture media containing 10% FBS . Although the growth of MSCs in serum-free CM was not higher than those in culture media containing 10% FBS, surface makers and differentiation capability of MSC were not significantly different. Based on these results, serum-free CM from mixed cells could be used for cultivation of MSCs and their differentiation capacity was maintained.

Mesenchymal stem cells (MSCs) are defined as multipotent progenitor cells with the ability to generate cartilage, bone, muscle, connective tissues and fat. MSCs have been typically obtained from the bone marrow (BM), adipose tissues, and umbilical cord blood. The development of in vitro systems of chondrogenesis such as the identification of protein factors that can promote chondrocyte differentiation of adult MSCs and improve cartilage repair in vivo is needed. Therefore we analyzed cartilage differentiation by human adult stem cells from BM stroma. In this study, to understand the mechanism of initial chondrogenesis, differentiated BM-MSCs were leaded to chondrocytes by treating BMP-6, TGF-β, Dexamethasone and ITX-Premix, and making pellets by centrifugation. The changes in protein profiles were monitored by 2-DE. And then the protein expression during the chondrogenesis were identified by MALDI-TOF, and were confirmed by RT-PCR. These protein profiles could be used for finding key proteins which promote the chondrogenesis and futher used for the quality control of chondrocytes for applications in cell therapy.

To support and enhance the in vitro growth and activity, the effects of various chemical factors, such as growth factors, cytokines, and hormones on cellular metabolic responses were investigated. It was recently reported that mechanical tension also play a central role in the physiology of a wide variety of tissues. In this study, we evaluate the effects of mechanical tension on the proliferation and ECM production of human dental pulp stem cells (DPSCs) using a flexwell system that imposed cyclic mechanical tension. This result that DPSC proliferation under tension varied with culture time. Mechanical tension increase the of lactate dehydrogenase during culture. RT-PCR mechanical tension increased collagen and osteopontin expression and decreased α -SMA expression. FACS analysis showed that CD105 expression did not change in all groups but CD 90 expression decreased at 8 % strain. In conclusion, that appropriate level of mechanical tension serve as a potent positive modulator of proliferation, differentiation and ECM production DPSCs.

Because isolated primary adult stem cells are low in numbers, in vitro expansion is necessary. However, the expansion potential is limited and in vitro aging leads to the loss of multipotency. Therefore, fast cultivation in short time is one of interests in cell therapy. In this study, we found that human periosteum-derived progenitor cells (PDPCs) are more proliferous and glycolytic than primary human mesenchymal stem cells (MSCs). Bone marrow-derived MSCs and umbilical cord blood-derived MSCs were used to compare with PDPCs in terms of growth rate. These cells were counted every 3 days. In addition, we investigated the effects of glucose consumption on the proliferation potential of PDPCs. Glucose consumption and glycogen synthesis were measured by glucose analyser and glucose assay kit. These results show that PDPCs can be used as an alternative source of cell therapy.

Cyclosporin A in preventing organ rejection was shown in liver transplants performed by Dr. Thomas Starzl at the University of Pittsburgh hospital. Possibilities for the development of cyclosporin A (CsA) as a new hair growth stimulator using excessive hair growth side effects have been reviewed in a variety of studies. For treatment of alopecia, some researchers transformed CsA structure into having low immunosuppression activity. The objectives of this study were (a) to evaluate the effect of a CsA derivative which has much low degree of immunosuppression and maintains a good hair growth on the number of organ cultured hair follicles and to assess proliferation of hair follicle keratinocytes, and (b) to study its effect on the extent of proliferation in hair follicle outer root sheath cells and on keratinocyte cell cultures in vitro.

Recent reports have suggested that tumors are organized in heterogeneous cell populations and that the capability to initiate malignancies including leukemia and solid tumors resides in only a small subset of cancer cells called cancer stem cells. In the case of human hepatocellular carcinoma (HCC), there are earlier studies showing HCC is originated and propagated from a small number of undifferentiated tumorigenic cells, which express CD133 as a tumorigenic marker in brain and prostate cancer. In this study, CD133+ cells were purified from a HCC cell line, Huh-7 via MACS, whose purity was confirmed using FACS and RT-PCR. The ability for self-renewal of the CD133+ cells was examined by colony-forming assay, and proliferative potential was evaluated by clonogenic assay. The differences between CD133+ cells and CD133- cells purified from Huh-7 were also analyzed via 2-DE. The differentially expressed proteins were analyzed with ImageMaster 2D Platinum 6.0 software and then identified by ESI-Q-TOF MS/MS. Among the identified proteins, certain proteins related to carcinogenesis and metastasis need be confirmed with Western blotting in a further study.

The anterior cruciate ligament (ACL), an intra-articular ligament of the knee, has important role for knee stabilization. However injured human ACL dose not have a functional healing response. Recently, many studies have reported that vibration exercise has positive effects such as increasing bone density, muscular strength regulating the endocrine system. Currently there is no scientific evidence to clarify the biomechanism involved in vibration stimulation. To determine the useful effect of vibration in vitro, we have applied 10% intensity and 20 Hz vibration to the primary cultured human ACL cells. Then, we have used two-dimensional electrophoresis (2-DE) in order to identify differently expressed proteins compared with control ACL cells: ACL cells without vibration treatment. Differently expressed proteins between control group and vibration treated group were found with ImageMaster 2D Platinum 6.0 software and identified by ESI-Q-TOF MS/MS. Among the identified proteins, some proteins which have a possibility to be involved in biomechanism of vibration stimulation should be confirmed with Western blotting in a further study.

Mesenchymal stem cells (MSC) exhibit finite proliferative potential in vitro, the so-called Hayflick limit. According to the free-radical theory, reactive oxygen species (ROS) may be potential candidates responsible for senescence and age-related diseases, and on production of high levels of ROS, the redox balance is disturbed and cells shift into a state of oxidative stress, which subsequently leads to premature senescence with shortening telomeres. H2O2 has been the most commonly used inducer of stress-induced premature senescence (SIPS), which shares features of replicative senescence (RS): similar morphology, senescence-associated β-galactosidase activity, cell cycle regulation, etc. Therefore, we confirmed the senescence of hMSC during SIPS by various analysis. And we performed proteome profiling to find regulators associated with senescence. Then we confirmed that the proteins we found are equally regulated in RS.

Mesenchymal stem cells (MSCs) hold great promise in cell-based therapies because of their multipotency and simple methods for in vitro expansion. However, during in vitro expansion, MSCs undergo aging and loss their multipotency and proliferation capability. Previous studies have reported that calorie restriction (CR) increases proliferation of MSCs and decreases apoptosis(1). Therefore, we examined the effect of low glucose in MSC in vitro. Proliferation in the low glucose (LG, 1.375 mM) condition was compared with that in the normal glucose (NG, 5.5 mM) condition. In addition, comparative studies of population doubling, β-galactosidase activity, ROS generation and differentiation capacity (osteocyte, adipocyte) in NG and LG conditions were performed. We compared protein expressions between NG and LG conditions, several proteins were up-regulated or down-regulated in glucose restriction condition, LG condition. Although a large-scale study is necessary to confirm the clinical function of the proteins elucidated in this study, these results imply that differentially-expressed proteins in LG condition may provide further information on the aging and differentiation of stem cells.

Microglia activation and release of nitric oxide (NO) have recently emerged as a key event mediating pathological cell damage in many neurodegenerative diseases. In this study, we examined possible anti-inflammatory effects of rosmarinic acid (RA), a naturally occurring hydroxylated polyphenolic compound in various herbs, on lipopolysaccharide (LPS)-induced NO production in BV-2 mouse microglial cells. Pretreatment of microglial cells with RA (50 uM) for 1 h resulted in a significant decrease in LPS-induced NO production. In addition, LPS-induced upregulation of iNOS and interferon-β (IFN-β) expression was significantly attenuated by RA. These results suggest that RA may provide therapeutic benefits for suppression of inflammatory-related injury in neurodegenerative diseases.

Variable glycosylation of antibodies occurs at Asn297 in the Fc region, specifically terminal galactosylation and sialylation. These variations may affect both pharmacokinetic behavior and effecter function, such as complement-dependant cytotoxicity (CDC). Among the variations in N-glycosylation of the antibodies analyzed, highly galactosylated and sialylated antibodies demonstrated in vivo efficacy. In this study, the degree of glycosylation of antibodies according to passages through the cell culture was compared in an attempt to find the condition showing greater in vivo efficacy of recombinant antibodies and so increasing their potential as therapeutic drugs. Suspension cultures of recombinant CHO cells were grown in protein-free media, and purification and analysis were performed using liquid chromatographic methods. The results demonstrate that glycosylation can be changed by cell growth phase and passages through the cell culture. In early death phase during cell culture, the antibody was highly glycosylated, and as the subculture was repeated and prolonged in the same culture condition, glycosylation of the antibodies was advanced. In summary, the N-glycosylation rate (i.e. the percentage of N-glycan types such as G0, G1, and G2) can be controlled by experimental timing.

Variable glycosylation of antibodies occurs at Asn297 in the Fc region, specifically terminal galactosylation and sialylation. These variations may affect both pharmacokinetic behavior and effecter function, such as complement-dependant cytotoxicity (CDC). In this study, the differential glycosylation of antibodies was compared, and physical parameters such as temperature and pH, were evaluated in an attempt to induce greater in vivo efficacy of recombinant antibodies and increase their potential as therapeutic drugs. Suspension cultures of recombinant CHO cells were grown in protein-free media, and purification and analysis were performed using liquid chromatographic methods. By altering physical parameters such as temperature and pH, the environmental parameters inducing glycosylation of the recombinant antibodies were studied. The results demonstrated that lowering temperature and pH during cultivation had a notion that suppress cell growth, increase batch culture time and enhance glycosylation of the recombinant antibodies. In summary, environmental parameters in cell culture can affect glycosylation of recombinant antibodies. These results provide a reference point not only for understanding the mechanism for glycosylation of glycoproteins, but also for the development of therapeutic proteins, including recombinant antibodies, in the industry.

Erythropoietin (EPO) is a glycoprotein hormone primarily synthesized in kidney and regulates mammalian erythropoiesis1). In this study, N-glycans of recombinant human erythropoietins (rhEPO) expressed in insect cells were analyzed to investigate the heterogeneity according to different cell culture methods. rhEPO was designed to have mouse derived IgM signal sequence for secretion out of the cell and IgG binding domain of protein A at N-terminal for efficient purification. Although insect cells are usually cultured at 27℃, various culture temperatures such as 24℃, 30℃, 33℃, 37℃ were tested. 24℃ showed highest productivity for rhEPO and the productivity was decreased according as the culture temperature increased. Where as the productivity was increased at low temperature, N-glycan profile of rhEPO from 24℃ culture was similar with that of 27℃ culture.

The goal of this study was to investigate the entrapment of three different drugs (Fluconazole, Tizanidine hydrochloride, and Gatifloxacin in gelatin nanoparticles. The particles were prepared by nanoprecipitation method using water or DMSO as solvent and Ethanol as nonsolvent. It led to a homogenous population of nanoparticles except in Tizanidine hydrochloride loaded case, where visible aggregates were found in the system. No loading was achieved in case of Fluconazole, while Tizanidine hydrocholide loaded crosslinked particles showed 16% loading efficiency which was decreased to 1-2% in uncrosslinked case. Contrarily the loading efficiency of Gatifloxacin loaded crosslinked particles was 5-6% and was increased to 15-20% when crosslinking was excluded from the procedure.

In this study novel nanoparticles were prepared by polyelectrolyte complexation between chitosan and Fucoidan at simple and mild conditions. Specifically the effect of pH of chitosan solution and chitosan-Fucoidan mass ratio was studied on the turbidity of the suspension, yield of the dried mass and particle size. The prepared chitosan-Fucoidan complex nanoparticles were observed by field emission sacnning electron microscope and the mean size of prepared nanoparticles located in matrix was measured as less than 100nm. The nanoparticles tended to grow as the pH of chitosan increased and the mass ratio of chitosan and Fucoidan decreased, which led to the formation of the aggregated nanoparticles.

Drug-loaded biodegradable polymeric nano- and microparticles are of great interest in the development of controlled-release devices for therapeutic applications. Recently, some studies on the incorporation of cyclodextrins (CDs) and their derivatives into polymeric drug delivery carriers such as microspheres, nanospheres and polymeric films have been conducted. In the present study, we will propose a novel method for producing poly(D,L-lactic-co-glycolic acid) (D,L-PLGA) nano- and microparticles through inclusion complexation (IC) with CD derivatives using an aerosol solvent extraction system (ASES) process with supercritical carbon dioxide (SCCO2) as an antisolvent. Various D,L-PLGA/CD IC particles of different molar ratios were produced at various temperatures and pressures by the ASES process. Ultrafine IC particles were prepared satisfactorily in molar ratios of D,L-PLGA monomer to CD ranging from 10:1 to 100:1. These results have shown that particle production of polymers with low glass transition temperatures through inclusion complexation with CDs and their derivatives using SCCO2 is a promising method, especially for controlled-release formulations of poorly water-soluble drugs.

Poly(lactic-co-glycolide) (PLGA) microspheres have been investigated for a long time as a protein/peptide delivery depot, and some products were already commercialized. However, recent publications have report about their disadvantages in the long term delivery of protein/peptide drugs such as the denaturation, aggregation, and deamidation of protein/peptide drug. The phenomena are induced by proton generated from the hydrolysis of ester linkages in PLGA. It is well known that an acidic condition facilitates the denaturation, aggregation, and deamidation. Therefore, the development of new protein/peptide delivery depot is necessary. In this study, pullulan acetate microsphere (PAM) was inspected as a depot for long term delivery of exendin-4 which is a drug for type II diabetes. It was prepared by w/o/w double emulsion method. The mean particle size of PAM ranged from 5 to 100 mm, as determined by SEM. Their shapes were regular and spherical, as visualized via SEM photographs. The exendin-4 loading efficiency of the microspheres was up to 90 wt. %. The microspheres may give an idea for development of new protein/peptide depot in long term delivery.

The present investigation was performed to evaluate the effect of hesperidin, a flavanone glycoside, on the antioxidant defense system and a lipid peroxidation against γ-radiation induced damage in rats. Exposure of the rats to γ-radiation (5 Gy) resulted in tissue damage characterized by significantly elevated levels of serum marker enzymes (AST, ALT, ALP, LDH, and CPK) and a decrease in their activities for the heart tissue. A γ-radiation induced oxidative stress was observed by the elevated levels of a lipid peroxidation and a decrease in the activities of the endogenous antioxidants (SOD, CAT, GPx and GSH) in the heart and kidney of the rats. Post-treatment with hesperidin (50 and 100 mg/kg, bw/day, orally) for 7 days following an exposure to γ-radiation significantly attenuated these changes when compared to the radiation exposed groups. Histopathological examination of the heart and kidney tissue of the rats exposed to a γ-radiation and treated with hesperidin also revealled minimal damage when compared to those exposed to γ-radiation alone. These findings indicate the protective effect of hesperidin on a lipid peroxidation and the antioxidant tissue defense system during γ-radiation induced tissue damage in rats.

Hesperidin, a citrus flavanoglycone, was investigated for its protective effect against γ-irradiation induced oxidative stress and DNA damage in the liver of rats. Male Sprague-Dawley rats were exposed to γ-irradiation (1Gy, 3Gy and 5Gy) and were post treated with hesperidin (50 mg/kg and 100 mg/kg, b.w, orally) for 7 days. Exposure to γ-irradiation resulted in hepatocellular damage, featuring higher levels of serum AST and ALT, and a simultaneous decrease in their levels in the liver tissue. Oxidative stress was evidenced by the elevated levels of a lipid peroxidation and a decrease in the levels of the key enzymic and non-enzymic antioxidants in the liver. However, the above γ-irradiation induced toxic effects were dramatically and dose-dependently relieved by hesperidin treatment as observed by the restoration in the altered levels of the marker enzymes, lipid peroxidation, enzymic and non-enzymic antioxidants. The histopathological observation of the liver tissue also supported the biochemical findings. The results show that an oral administration of hesperidin can offer a protection against γ-irradiation induced hepatocellular damage and oxidative stress in rats, probably by exerting a protective effect against a hepatocellular necrosis via its free radical scavenging and membrane stabilizing abilities.

Atopic dermatitis (AD) in humans is a chronic pruritic inflammatory disease that fluctuates with remissions and progressions. It is considered that AD may be due to various genetic and environmental factors, a skin barrier, immune factors and stress (1); however, its exact etiology is unclear. Therefore, it is worthwhile to establish a suitable animal model to elucidate the pathogenesis of AD and to develop new approaches for therapy. Immune response and skin lesions, which are generally observed in patients with AD, have been indicated as major diagnostic criteria (2, 3). Recently, animal models of AD, including NC/Nga mouse and hapten-induced mouse models, have received increasing attention. This study was designed to compare three mouse models for AD: 2,4-dinitrochlorobenzene (DNCB) induced NC/Nga model, DNCB induced Hairless model and DNCB induced BALB/c model. Result, DNCB induced NC/Nga model revealed AD-like severe skin lesions and the Hairless model revealed a Th2-dominated immune response in serum. On the other hand, for the BALB/c model, it did not reveal skin and immune responses. In summary, the NC/Nga and Hairless models are mainly attributable to DNCB, and these models can be used as AD models.

PEI used as an effective non-viral gene delivery vector in vitro and in vivo1). Although it has high transfection efficiency, it makes a damage to normal cell membrane2,3). In order to improve the transfection efficiency of non-viral vector and to reduce the cytotoxicity of polyethylenimine (PEI), the branched PEI (25kDa) and all-trans-retinoic acid (ATRA) conjugates were synthesized by carbodiimido method (PRA). The synthesis was confirmed by NMR, FT-IR and UV-spectrophotometer, There physicochemical properties were characterized by gel electrophoresis, particle size and zeta potential to estimate a possibility as a gene carrier. The transfection efficiency of PRA in NIH3T3 cell was up to 1.5 times higher than that of PEI (N/P 15). The cytotoxicity of PRA was also measured by MTT assay. PRA conjugates showed lower cytotoxicity compared with the PEI. Therefore, the PRA conjugate may be good candidate for non-viral gene carrier.

The purpose of this study was to develop nanoparticle which have a specificity at tumor site and multidrug resistant cancer cells. A cationic polymer/vitamin conjugated for preparation of the nanoparticles. The cationic polymer has cytotoxicity, but the nanoparticle from the conjugate slightly reduced the toxicity. However, there are still remained a toxicity. For this reason, the nanoparticle was covered with biocompatible polysaccharide(BP) which can be easily degraded by an enzyme from tumor site.1) And the vitamin has a hydrophobicity, so the nanoparticle can loaded with hydrophbic anticancer drug. Drug loaded nanoparticle was expected that MDR effect should be reduced, and the the cationic polymer increase a anticancer effect.2) The cytotoxicity of the nanoparticle measured by MTT assay depended on the enzyme concentration. The interaction between the nanoparticle and cancer cells was observed by confocal microscopy as a function of BP concentration. The result indicated that BP can enhance the specificity of tumor site due to inhibit the internalization of the nanoparticle in the normal tissue.

Paclitaxel is a taxane diterpene amide and was first isolated from the stem bark of the Pacific yew tree, Taxus brevifolia. This natural product has proven to be useful in the treatment of a variety of human neoplastic disorders such as platinum-resistant ovarian cancer, breast cancer, and non-small cell lung cancer and leukemia, AIDS-related Kaposi' s sarcoma, and other cancers. In this work, paclitaxel, a poorly water-soluble compound, was formulated with hydroxypropyl-β-cyclodextrin (HP-β-CD) and poly(L-lactic acid) (PLLA) in order to enhance its solubility and achieve controlled release. First, HP-β-CD and PLLA were inclusion complexed using a ultrasound-assisted solution method. Paclitaxel-loaded inclusion complex microparticles were then prepared by a supercritical aerosol solvent extraction system (ASES) process. The effects of pressure, temperature, solution concentration, and CO2 flow rate on the morphology, drug content, encapsulation efficiency, and release characteristics were investigated in detail. The physicochemical properties of ASES processed microparticles were characterized by FE-SEM, HPLC, and DSC.

Diabetic nephropathy (DN) is the most common cause for end stage renal disease (ESRD). Proteomics and metabolomics offer a nonbiased suite of tools to address pathophysiologic mechanisms and discovery of biomarkers associated to disease. In this study, serum protein expressions in diabetic patients without complications and patients who have microalbuminurea were compared using serial cut-off to enrich low-molecular-weight proteome. Three spots were up-regulated about 100-200% in microalbuminuric patients compared to normoalbuminuric patients. Among these differentially expressed spots apolipoprotein A-Ⅳ was identified with ESI-Q-TOF mass spectrometry. Secondly, peptides whose molecular weight less than 10 kD were analysed with reversed-phase high performance liquid chromatography (RP-HPLC). Fractions showing different % peak area were collected and peptides were analyzed by N-terminal sequencing. Eight amino acid residues were detected and the peptide was identified as potassium channel, subfamily K, member 6 variant. Finally, filtrates of 3 kD cut-off membrane were analyzed by nuclear magnetic resonance (NMR) apparatus to search metabolites affected with diabetic nephropathy.

Uncoupling proteins (UCPs) are a family of mitochondrial anion-carrier proteins that are implicated in the regulation of mitochondrial membrane potential and cellular energy metabolism. USP4, a member of uncoupling proteins, is exclusively expressed in the brain, but the function of this mitochondrial protein in the brain is not well known. We explored the effects of increased UCP4 expression on the reactive oxygen species (ROS) and Caspase-3 levels, and cell viability, under normal and MPP+-induced cytotoxic conditions, in murine dopaminergic cells. MPP+ treatment elicited ROS increase and activation of Caspase-3 activity. However, cells overexpressing UCP4 showed significantly attenuated ROS level and Caspase-3 activity. These results suggest that UCP4 overexpression can inhibit apoptosis of dopaminergic neurons.

Thermo-sensitive hydrogels are commonly used in many biomedical and pharmaceutical applications, including tissue engineering and drug delivery systems. Due to their sensitivity to thermal stimulus, they have a great potential in site-specific controlled drug-delivery systems. A new class of injectable and bioabsorbable supramolecular hydrogels, which are formed from poly(ethylene oxide) (PEO) and α-cyclodextrin (α-CD), have been investigated for controlled drug delivery. In this study, we examined the release profiles of several poorly water-soluble drugs from these new biodegradable hydrogels. Physically crosslinked hydrogels were prepared from mixed aqueous solutions of PEO and α-CD using a temperature-controlled gelation technique at various concentrations of both compounds. The drug release profiles of several drugs from hydrogels were determined in vitro via dialysis using high-performance liquid chromatography.

Polymeric nanoparticles are emerging as attractive drug delivery systems. Hydrophobic drugs including photosensitizers for photodynamic therapy can be covalently bound or physically entrapped in the core of the nanoparticles and thus be systemically delivered to tumors or choroidal neovascularization... It can be concluded that both leakage and photothrombic activity of PSs incorporated in the NPs were strongly affected by the hydrophobic/hydrophilic character of these molecules. theoretically speaking, NPs formulated with the more hydrophobic PSs such as mTPP, appear to be promising candidates for encapsulation in biodegradable nanoparticles. Here, mTPP was incorporated into sterile submicronic nanoparticles of poly(D,L -lactide-co-glycolide) (50:50 and 75:25 PLGA) and poly(D,L-lactide) (PLA). sub-300 nm mTPP-loaded nanoparticles with relative high drug loadings and entrapment efficiencies were produced using the emulsification–diffusion technique. All the NP size,DLS plots,drug-loading,entrapment efficiency measurements performed allow us conclude that mTPP loaded 50:50 PLGA nanoparticle is a promising drug delivery system for photodynamic therapy.