Molecular hydrogen suppresses Porphyromonas gingivalis lipopolysaccharide-induced increases in interleukin-1 alpha and interleukin-6 secretion in human gingival cells.

Periodontitis is defined as a multifactorial polymicrobial infection accompanied by inflammatory reactions. Porphyromonas gingivalis (Pg) is known as a major pathogen in the initiation and progression of periodontitis, and a major virulence factor is Pg lipopolysaccharide (LPS). Molecular hydrogen (H2) has been reported to act as a gaseous antioxidant, which suppresses periodontitis progression by decreasing gingival oxidative stress. However, no human periodontitis model has examined the anti-inflammatory effects of H2. In this study, we examined the effects of H2 on Pg LPS-induced secretion of 8 types of inflammation markers in a human periodontitis model using human gingival cells with enzyme-linked immunosorbent assays. Our results demonstrated that Pg LPS increased interleukin (IL) 1 alpha (IL-1α) and IL-6 secretion, but H2 significantly suppressed the secretion of both cytokines without cytotoxicity. H2 can suppress the production of IL-1α and IL-6, which are identified as cytokines involved in inflammatory reactions in periodontal disease. Thus, H2 may provide therapeutic applications for periodontitis.

Protective effects of dissolved molecular hydrogen against hydrogen peroxide-, hydroperoxide-, and glyoxal-induced injuries to human skin keratinocytes.

Molecular hydrogen (H2) is recognized as a gaseous antioxidant, and it is expected to ameliorate various disorders related to oxidative stress and inflammation. However, there are still many unclear points regarding its effectiveness in the skin. Therefore, the purpose of this study was to examine the protective effect of H2 against ultraviolet (UV) irradiation-related stress injury in human epidermal HaCaT cells. We investigated the effects of H2 against three types of UV-derived oxidative stress using human skin keratinocytes: hydrogen peroxide (H2O2)-induced oxidative stress, tert-butyl hydroperoxide (t-BuOOH)-induced lipid peroxidation stress, and glyoxal-induced carbonyl stress. Our results showed that H2 exerted cytoprotective effects against stress induced by H2O2, t-BuOOH, and glyoxal. Furthermore, our results also revealed that H2 suppressed H2O2-induced increases in intracellular peroxide and H2O2 levels, and suppressed the progression of lipid peroxidation. Taken together, our results demonstrate that H2 can exert protective effects against oxidative stress-, lipid peroxidation-, and carbonyl stress-induced cellular injuries in human keratinocytes, partly mediated via suppression of intracellular oxidative stress and peroxide generation. Therefore, H2 is expected to be utilized as an effective and attractive component in cosmetic formulations in the future.

Resveratrol potentiates intracellular ascorbic acid enrichment through dehydroascorbic acid transport and/or its intracellular reduction in HaCaT cells.

L-Ascorbic acid (AsA), a reduced vitamin C (VC), is an important antioxidant, and the internal accumulation and maintenance of AsA are thought to play a significant role in various physiological activities in humans. We focused on resveratrol (RSV), a natural polyphenolic compound, as a candidate for an AsA transport modulator and investigated whether RSV can affect the intracellular VC accumulation after either AsA or dehydroascorbic acid (DHA) addition in HaCaT keratinocytes. Our results demonstrate that RSV treatment could significantly enhance intracellular VC levels after either AsA or DHA supplementation, and intracellular VC accumulated mainly as AsA. Our results also indicate that most of the intracellular transported DHA was reduced to AsA and accumulated after uptake into cells. In addition, RSV could induce several AsA or DHA transport-related and intracellular DHA reduction-related genes including SVCT2, GLUT3, TXNRD2, and TXNRD3, necessary for AsA transport, DHA transport, and DHA reduction/regeneration, respectively. On the other hand, the both protein expression levels and the localizations of sodium-dependent vitamin C transporters 2 (SVCT2) and glucose transporter 3(GLUT3) were scarcely affected by RSV treatment. Furthermore, RSV-induced enrichment of intracellular AsA levels was completely suppressed by a GLUT inhibitor cytochalasin B. These results suggest that RSV can potentiate intracellular AsA accumulation via activation of the DHA transport and subsequent intracellular reduction from DHA to AsA. Thus, RSV might be useful for maintaining substantial AsA accumulation in the skin keratinocytes.

The influence of cellular senescence on intracellular vitamin C transport, accumulation, and function.

In humans, vitamin C (VC) accumulates at higher concentrations in cells than in plasma, and this intracellular accumulation appears critical to several important physiological functions. However, although VC accumulation decreases in the elderly, the influence of cellular senescence on the transport, accumulation, and function of VC is poorly understood. In this study, we investigated the effects of supplementation with both ascorbic acid (AsA) and dehydroascorbic acid (DehAsA) on the uptake and accumulation of VC, AsA, and DehAsA into cells and the effect of AsA on the levels of intracellular reactive oxygen species (ROS) in human fibroblast TIG-1 cells. We also assessed how that supplementation affected senescence-associated changes in intracellular VC transport and accumulation. AsA supplementation significantly increased intracellular levels of AsA, DehAsA, and total VC (i.e., reduced AsA plus oxidized DehAsA) in senescent cells compared with young cells. DehAsA supplementation also significantly increased intracellular AsA and total VC levels in senescent cells, but not DehAsA, and the increases were less than after adding AsA. Among the molecules related to VC accumulation, the mRNA and protein expressions of sodium-dependent VC transporter 2 (SLC23A2) were increased in senescent cells. Furthermore, intracellular peroxide and superoxide anion levels were higher in senescent cells, with AsA supplementation markedly attenuating spontaneous intracellular peroxide accumulation. Overall, our results therefore suggest that VC transport and accumulation improved in senescent human fibroblast TIG-1 cells due to the adaptive upregulation of sodium-dependent VC transporter 2 in response to increased ROS levels. We conclude that adequate supplementation with AsA can effectively mitigate senescence-associated intracellular ROS.

Effects of Platinum Nanocolloid in Combination with Gamma Irradiation on Normal Human Esophageal Epithelial Cells.

Our previous study demonstrated that platinum nanocolloid (Pt-nc), combined with lower-dose gamma irradiation at 3, 5, and 7 Gy significantly decreased proliferation and accelerated apoptosis of the human esophageal squamous cell carcinoma-derived cell line KYSE-70. The aim of the present study was to determine, under the same conditions as our previous study where gamma rays combined with Pt-nc were carcinostatic to KYSE-70 cells, if we could induce a radioprotective or the radiation-sensitizing effect on the human normal esophageal epithelial cells (HEEpiC). HEEpiC were treated with various Pt-nc concentrations and then irradiated with various gamma-ray doses. The proliferative status of HEEpiC was evaluated using trypan blue dye-exclusion and WST-8 assays. The cellular and nucleic morphological features were determined using crystal violet and Hoechst 33342 stainings, respectively. The intracellular level of reactive oxygen species (ROS) in HEEpiC was evaluated with a nitro blue tetrazolium (NBT) assay. The apoptotic status was detected with caspase-3, Bax, and Bcl-2 by Western blotting. Either Pt-nc or gamma irradiation could inhibit the growth of HEEpiC; however, their combined use exerted a significant proliferation-inhibitory effect in a Pt-nc dose-dependent manner than gamma irradiation alone. Pt-nc resulted in radiation sensitization rather than radiation protection on HEEpiC in vitro similar to KYSE-70 cells, when Pt-nc was administrated alone or combined with gamma irradiation. Thus, Pt-nc has an inhibitory effect on cell proliferation, a facilitative effect on apoptosis, and a certain degree of toxicity against HEEpiC.

Oleic acid promotes adaptability against oxidative stress in 3T3-L1 cells through lipohormesis.

Although fatty acids are important components of biological membranes, energy sources, and signal transducers or precursors of lipid mediators, excess intake of fatty acids and their accumulation cause obesity and metabolic syndrome. Thus, fatty acid quantity is known to be an important factor for obesity-related diseases, but the effects of different types of fatty acids (i.e., fatty acid quality) on human health are not completely understood. We here focused on the relationship between fatty acid quality and oxidative stress by investigating whether resistibility to tert-butyl hydrperoxide (t-BuOOH)-induced oxidative stress in 3T3-L1 cells varied according to the fatty acid type. Among eight fatty acids (both saturated and unsaturated) tested, oleic acid (OA) exerted the most pronounced cytoprotective effects, with efficacy over a wide range of concentrations. OA treatment markedly enhanced the intracellular levels of lipid peroxidation markers, including N(ε)-(hexanoyl)lysine, 4-hydroxy-2-nonenal, and acrolein. The levels of these markers in OA-treated cells were decreased after t-BuOOH exposure, whereas the levels in untreated control cells were notably increased after t-BuOOH exposure. Our results suggested that unsaturated fatty acids, particularly OA, could promote an adaptive response and enhance cell tolerance through increased cellular antioxidative capacity via OA-induced mild lipid peroxidation (lipohormesis), and thus protect cells against subsequent oxidative stress-related injury.

Photodynamic anti-cancer effects of fullerene [C60]-PEG complex on fibrosarcomas preferentially over normal fibroblasts in terms of fullerene uptake and cytotoxicity.

A water-soluble complex of fullerene [C60]:polyethylene glycol (PEG) (1:350 wt/wt) (C60-PEG), but not PEG alone, was found in the present study by ESR/DMPO spin-trap method to generate hydroxyl radicals 6.5-fold as abundant as the non-irradiation level, when irradiated with visible light (400-600 nm, 140 J/cm(2): 450-fold as intense as in average outdoor), but not to generate without irradiation. At 3 h after irradiation with C60-PEG, human fibrosarcoma cells HT1080 were obviously degenerated together with diminished microvilli, cell shrinkage and cell fragmentation as observed by SEM and were shown either for increased cytotoxicity by dual stains with calcein-AM and propidium iodide or for nuclear condensation and fragmentation by Hoechst 33342 stain, any of which were, in contrast, scarcely changed in normal human fibroblastic cells DUMS16 derived from the same connective tissue type as HT1080 cells. Under the conditions, the maximum intracellular uptake amount was more abundant for HT1080 cells than for DUMS16 cells, either by immunostain/fluorography using polyclonal antibody against fullerene [C60], or by HPLC method indicating the 2.4-fold preferential uptake of C60-PEG into HT1080 cells, suggested to greater phagocytotic ability characteristic of cancer cells, over DUMS16 cells being non-macrophage-like normal cells. Thus, C60-PEG is expected as a photosensitizer for photodynamic therapy with scarce side effects to normal cells and preferential reactive oxygen species generation in cancer cells.

Fullerene-C60 derivatives prevent UV-irradiation/ TiO2-induced cytotoxicity on keratinocytes and 3D-skin tissues through antioxidant actions.

Microcorpuscular titanium dioxide (TiO2), a useful sunscreen agent, photocatalyzes generation of reactive oxygen species (ROS). We assessed protective effects of fullerene-C60 derivatives or microcolloidal platinum (Pt) against ultraviolet ray (UV)-irradiation in the presence of TiO2 in vitro. UV-irradiation (8 J/cm2, mixed UVA and UVB) in the presence of 15 ppm TiO2 on HaCaT keratinocytes decreased cell viability as quantified by WST-1 assay, and increased both intracellular ROS and cell-membrane-lipid peroxidation, as quantified by nitroblue-tetrazolium (NBT) assay and diphenyl-1-pyrenylphosphine (DPPP) assay, respectively, whereas all of three phototoxicity-related symptoms were appreciably repressed almost to UV-unirradiational levels by pretreatment with polyvinylpyrrolidone-entrapped fullerene-C60 (C60/PVP) or fullerene-C60 dissolved in squalane (C60/Sqn) in a dose-dependent manner of C60, but scarcely by PVP alone or Sqn alone. In contrast, Pt repressed intracellular ROS generation, but did not prevent either peroxidation of cell-membrane-lipid or cell mortality. Then in the epidermis of 3-dimensional human skin tissue model, UV-irradiation in the presence of TiO2 extensively induced two symptoms such as ROS-generation around perinuclear regions and membrane-lipid peroxidation, both of which were repressed by C60/PVP or C60/Sqn, whereas Pt did not prevent membrane-lipid peroxidation adequately. Thus the advantageous application of the lipophilic antioxidant fullerene-C60 which effectively protects cell membrane against peroxidation. In conclusion, fullerene-C60 can be expected to serve as an antioxidant for scavenging of TiO2-photocatalyzed ROS in the skin surface, and therefore provide a functional improvement of TiO2-containing sunscreens.

Senescence-induced increases in intracellular oxidative stress and enhancement of the need for ascorbic acid in human fibroblasts.

Many studies have suggested that there is a close correlation among declines in internal ascorbic acid (AsA) levels, various disorders, and senescence. To clarify the relationships between age-associated changes in intracellular AsA levels and the effects of AsA administration on intracellular reactive oxygen species (ROS) levels, we investigated aging-related changes in AsA uptake, ROS levels, and the effects of AsA administration on intracellular ROS levels in young and old (senescent) human fibroblasts. Our results demonstrated that AsA uptake was increased in old cells compared with young cells, although mRNA and protein expression of sodium-dependent vitamin C transporter 2 was barely altered between the young and old cells. We also demonstrated that the intracellular superoxide anion level was higher in young cells, whereas the level of intracellular peroxides was significantly increased in old cells under both normal and oxidative stress conditions. Moreover, AsA administration markedly decreased the augmentation of intracellular peroxides in old cells, whereas there was no effect of AsA treatment in young cells under both normal and oxidative stress conditions. Therefore, our results also indicate that AsA could play an important role in regulating the intracellular ROS levels in senescent cells and that the need for AsA is enhanced by cellular senescence.

Repressive effects of a capacitive-resistive electric transfer (CRet) hyperthermic apparatus combined with provitamin C on intracellular lipid-droplets formation in adipocytes.

PURPOSE: The aim of this study was to evaluate inhibitory effects of L-ascorbic acid-2-O-phosphate-Na(2) (APS), a pro-vitamin C, combined with hyperthermia on adipogenic differentiation of mouse stromal cells, OP9. MATERIALS AND METHODS: OP9 preadipocytes were differentiated with serum replacement, administered with APS, and simultaneously treated with hyperthermia using a capacitive-resistive electric transfer (CRet) apparatus, which was conducted repeatedly twice a day. After 2 days, intracellular lipid droplets were stained with Oil Red O, then observed by microscopy and assessed spectrophotometrically. RESULTS: After stimulation by serum replacement for 2 days, lipid droplets were accumulated surrounding nucleus of OP9 cells. When APS of 0.15-0.6 mM was administered without hyperthermia, the amount of lipid droplets was markedly suppressed to 50.5%∼-11.3% versus the undifferentiated control, and diminished huge aggregates of lipid droplets. In OP9 cells treated by hyperthermia at 42°C for 0.5 min, 1 min or 3 min in the absence of APS, adipogenesis was suppressed abruptly in a time-dependent manner to 95.4%, 18.7% or -5.5%, respectively. Whereas, the percentage of adipogenesis was 96.8% in OP9 cells treated by mild hyperthermia alone at 41°C for 1 min. The simultaneous application of APS and hyperthermia at 41°C for 1 min markedly suppressed the accumulation of lipid droplets to 25.7%∼-66.2%. By scanning electron microscopy (SEM) observation, the surface of OP9 cells treated with APS and hyperthermia appeared to have the morphological property of undifferentiated OP9 cells. CONCLUSION: Combined treatment of APS and mild hyperthermia suppresses adipogenesis in OP9 cells, particularly in lipid droplets accumulation during spontaneous differentiation of OP9 preadipocytes.

Inhibitions by hydrogen-occluding silica microcluster to melanogenesis in human pigment cells and tyrosinase reaction.

We investigated the anti-melanogenetic efficacy of hydrogen-occluding silica microcluster (H2-Silica), which is a silsesquioxane-based compound with hydrogen interstitially embedded in a matrix of caged silica, against melanogenesis in HMV-II human melanoma cells and L-DOPA-tyrosinase reaction [EC1.14.18.1]. HMV-II cells were subjected to oxidative stress by ultraviolet ray-A (UVA) exposure of 3-times of 0.65 J/cm2 summed up to 1.95 J/cm2. After UVA irradiation, HMV-II cells were stimulated to produce melanin by 2.72-fold more abundantly than unirradiated control. When HMV-II cells were treated with H2-Silica of 20 ppm or kojic acid of 28.4 ppm before and after UVA-irradiation, the amount of melanin was repressed to 12.2% or 14.5% as compared to that of UVA-irradiated control, respectively. That is, H2-Silica exhibited a comparable efficacy to the whitening agent kojic acid. The H2-Silica could prevent melanogenesis in HMV-II cells by low-level doses at 1-10 ppm, and cell viability and apoptosis event did not change even by high-level doses at 100-1000 ppm. On the contrary, kojic acid was cytotoxic at the concentration of 14-28 ppm or more. By microscopic observation, H2-Silica suppressed such properties indicative of melanin-rich cells as cellular hypertrophy, cell process formation, and melanogenesis around the outside of nuclei. The enzymatic assay using L-DOPA and mushroom tyrosinase demonstrated that H2-Silica restrained UVA-mediated melanin formation owing to down-regulation of tyrosinase activity, which could be attributed to scavenging of free radicals and inhibition of L-DOPA-to-dopachrome oxidation by hydrogen released from H2-Silica. Thus H2-Silica has a potential to prevent melanin production against UVA and serves as a skin-lightening ingredient for supplements or cosmetics.

Polyhydroxylated fullerene C60(OH)44 suppresses intracellular lipid accumulation together with repression of intracellular superoxide anion radicals and subsequent PPARγ2 expression during spontaneous differentiation of OP9 preadipocytes into adipocytes.

Reactive oxygen species has been suggested to be one of the key factors associated with the development of obesity. During spontaneous differentiation of mouse stromal preadipocytes OP9 into adipocytes, intracellular superoxide anion radicals (O (2) (-.) ) level markedly increases and is accompanied by a significant elevation of intracellular lipid accumulation. This differentiation-dependent increase in intracellular O (2) (-.) level positively correlated with the intracellular augmentation of the lipid level. Super-highly hydroxylated fullerene (SHH-F; C(60)(OH)(44)), a novel polyhydroxylated fullerene derivative, quenched intracellular O (2) (-.) , and lipid accumulation to 38.7 and 42.7 % of that in the control, respectively. By thin-layer chromatographic analysis of extracted cellular lipid components, SHH-F clearly decreased the triglycerides ratio in the whole lipid droplet fraction, but scarcely influenced other lipids components. PPARγ2 expression, which plays a key role in regulating adipogenic differentiation, was significantly suppressed by SHH-F at the late stage of differentiation, with unaltered PPARγ1 expression. The intracellular superoxide anion radical augmentation preceded expression of PPARγ2, strongly suggesting that the primary O (2) (-.) generation was closely associated with lipid accumulation and subsequent PPARγ2 induction. These results indicate that SHH-F suppresses intracellular lipid accumulation, particularly in lipid droplets, and decreases O (2) (-.) level and subsequent PPARγ2 upregulation during spontaneous differentiation of OP9 preadipocytes into adipocytes.

Colloidal platinum in hydrogen-rich water exhibits radical-scavenging activity and improves blood fluidity.

The 'colloidal platinum' stabilized with polyvinylpyrrolidone (Pt/PVP-colloid) was dispersed in hydrogen-rich water (HW; hydrogen concentration, 0.82 ppm; oxidation-reduction potential, -583 mV) or regular water (RW; <0.01 ppm, +218 mV). And we evaluated the antioxidant activity of Pt/PVP-colloid in HW or RW on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and improvement of blood fluidity under 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH)-induced oxidative stress. When applied with the 0.25-0.5 ppm Pt/PVP-colloid in RW or HW, the level of DPPH radicals decreased to 77.5-59.6% or 16.1-5.6%, in contrast to the level as high as 81.3% for HW alone, respectively, as measured by an electron spin resonance method. The horse blood, which was subjected to AAPH-induced oxidative stress, was incubated for 24 hr with RW or HW, and thereafter required 13.7 sec (100%) or 5.7 sec (42.3%) for passing through the micro-channels in a rheology equipment. When treated with 0.5-1.0 ppm Pt/PVP-colloid in RW or HW, the blood passage time in the micro-channels decreased dose-dependently to 9.7-7.3 sec (71.6-53.8%) or 4.3-1.3 sec (32.8-10.3%), and the rate of micro-channels clogged with erythrocyte aggregates decreased to 23.8-21.0% or 15.8-9.8%, respectively, from 42.8% for no addition of Pt/PVP. By scanning electron microscopy, AAPH-treated erythrocytes lost intact surface morphology on the membrane together with protrusions and without hollows, being indicative of impaired transforming ability, and the rate of erythrocyte agglutination was increased to 46.2%. When treated the horse blood with HW alone significantly decreased the rate of erythrocyte agglutination to 29.6%, whereas 1.0 ppm Pt/PVP-colloid in RW or HW decreased it to 24.1% or 21.1%, respectively. Thus, DPPH-radical-scavenging and erythrocyte-protecting effects of Pt/PVP-colloid in HW were superior to those of Pt/PVP-colloid in RW or Pt/PVP-free HW. The results could be mainly attributed to the enhanced antioxidant activity of Pt/PVP in HW, which may be due to captured-hydrogen on platinum.

Anticancer effects of fullerene [C60] included in polyethylene glycol combined with visible light irradiation through ROS generation and DNA fragmentation on fibrosarcoma cells with scarce cytotoxicity to normal fibroblasts.

Fullerene [C60] included in polyethylene glycol (PEG) at a composing ratio of 1:350 w/w was examined for anticancer effects upon photodynamic therapy (PDT). Human connective tissue-derived fibrosarcoma cells HT1080 were decreased for a viability of 50% or 30%, by 3-h administration with PEG-fullerene [C60] at 50 or 100 ppm fullerene [C60] equivalent, respectively, subsequent rinsing out and irradiation with visible light (400-600 nm, 140 J/cm2: 450-fold as intense as in average outdoor), whereas the same tissue type-derived normal fibroblastic cells DUMS16 retained a viability of 93% or 85% under the same conditions. Anticancer effects were dependent on PEG-fullerene [C60] concentrations and irradiation doses, and scarcely exerted by PEG-fullerene [C60] alone, irradiation alone, or by fullerene [C60]-free PEG combined with irradiation, suggesting that the active principle may be fullerene [C60] as small as 0.0028 wt% versus the whole compound. Irradiation with PEG-fullerene [C60] occurred in intracellular DNA fragmentation according to TUNEL assay, and produced reactive oxygen species (ROS) such as hydroperoxides and peroxyl radicals or superoxide anion radicals in HT1080 cells as demonstrated by CDCFH-DA assay or nitroblue tetrazolium assay, respectively. Thus, PEG-fullerene [C60] is expected to be applied to anticancer PDT with scarce side effects on normal cells.

Fullerene-C60 incorporated in liposome exerts persistent hydroxyl radical-scavenging activity and cytoprotection in UVA/B-irradiated keratinocytes.

The aim of this study is to examine antioxidant activity of fullerene-C60 (C60) incorporated in liposome (LpsmFlln, a diameter of 75.6 nm). LpsmFlln is water-soluble, and composed of hydrogenated lecithin of 89.7%, glycine soja sterol of 10% and C60 of 0.3%. Hydroxyl radicals (*OH), generated from UVA- or UVB-irradiated H2O2, were scavenged by LpsmFlln but not by C60-lacking Lpsm as assessed by ESR, showing that the active principle is C60 as scanty as 1/415 weight versus LpsmFlln; the *OH amount (% of non-additive control) was decreased, LpsmFlln-dose-dependently, and for 0.5% LpsmFlln (C60-eq.:16.7 microM) to 34.1% or 78.3% upon irradiation with UVA (12 J/cm2) or UVB (500 mJ/cm2), respectively, showing the superiority for UVA to UVB in terms of the *OH scavenging of LpsmFlln. Cell viability of human skin keratinocytes HaCaT decreased to 41.1% upon UVA-irradiation at 10 J/cm2, but retained to 60.6% with 0.025% LpsmFlln (C60-eq.: 0.84 microM) together with prevention of cell-morphological degeneration, in contrast to scarce effects of C60-lacking Lpsm. The scavenging activity for Fenton reaction-generated *OH, detected by DMPO/ESR, was 96.2% or 72.2% (% of no-additive control) at 1 min and decreased time-dependently to 24.8% or 28.3% at 12 min with 16.7 microM L-ascorbic acid (Asc) or Trolox, respectively, whereas 0.5% LpsmFlln (C60-eq:16.7 microM, the same concentration as for Asc) diminished *OH by 90.9% at 1 min and 91.5% even at 12 min, demonstrating the superiority of LpsmFlln to Asc or Trolox in terms of persistence of *OH-scavenging ability. Repressive efficacy on beta-carotene discoloration (% of control) for 60 min was in the order, based on the same molar or weight concentration: 1.3%:3.34 microM Asc < 25.0%:0.1% Lpsm < 36.3%:0.1% LpsmFlln (C60-eq.:3.34 microM) < 57.2%:3.34 microM Trolox, indicating the preventive effect of LpsmFlln against beta-carotene oxidation. Thus, LpsmFlln was demonstrated for an antioxidant ability characteristic of long-term persistence, and is attributed to fullerene-C60 but scarcely to Lpsm in all the tests examined, and is expected as the skin-protecting agent against oxidative stress.

Carcinostatic effects of alkanoyl ascorbate plus platinum nano-colloid and stabilization of the esterolytically resultant ascorbate by hydrogen.

Carcinostatic effects of combined use of ascorbic acid (Asc), 2-O-phospho- or 6-O-palmitoyl ascorbate (Asc2Phos, Asc6Palm) or diverse alkanoyl Asc, and nano-sized platinum-poly(N-vinyl-pyrrolidone) colloid (PVP-Pt; 2-nm diameter) were examined on human esophagus carcinoma-derived cells KYSE70. Cell viability was repressed by 'Asc6Palm + PVP-Pt' mixture more markedly than by Asc6Palm or PVP-Pt alone, together with cell shrinkage and fragmentation, in contrast to no additive carcinostatic effect of 'Asc + PVP-Pt' or 'Asc2Phos + PVP-Pt'. The effects might be partly due to efficiency for intracellular uptake of PVP-Pt, as previously shown by our studies that Pt atoms composed of PVP-Pt were incorporated into human tongue carcinoma cells by 9.6-fold compared to normal human tongue epitheliocytes. Asc6Palm was advantageous for intracellular uptake, in terms of the proper balance for molecular hydrophilicity-lipophilicity (BMHL), whereas 6-O-stearoyl (C18) Asc or 2,6-O-dipalmitoyl (2 × C16) was demonstrated to be less carcinostatic owing to a lower BMHL. Although esterolytically converted from Asc6Palm, Asc was necessitated to be retained for efficient carcinostasis, and demonstrated by HPLC-coulometric ECD analysis to be appreciably stabilized in electrolytically generated hydrogen (dissolved hydrogen: 0.575 mg/L)-water, but scarcely in hydrogen-gas-bubbled water (0.427 mg/L), Mg stick-derived hydrogen (0.044 mg/L) water, or tap water, suggesting that hydrogen-rich water suppresses oxidative decomposition of Asc. Thus, Asc6Palm plus PVP-Pt with hydrogen-rich water supplement might be applicable for carcinostatic therapy.

Combined treatment with dissolved hydrogen molecule and platinum nanocolloid exerts carcinostatic/carcinocidal effects by increasing hydrogen peroxide generation and cell death in the human gastric cancer cell line NUGC-4.

Many studies have shown that redox regulation is an effective therapeutic strategy for different types of cancer. We have previously demonstrated that combined treatment with dissolved hydrogen molecule (H2) and platinum nanocolloid (Pt-nc) has carcinostatic effects and that increased intracellular reactive oxygen species (ROS) levels were closely associated with carcinostatic effects in Ehrlich mouse ascites tumor cells. However, it is unknown whether combined treatment-induced ROS generation can occur in human cancer cells. Therefore, this study aimed to examine the carcinostatic effect of the combined treatment in human cells and investigate the relationship between treatment efficacy and ROS generation. H2 and Pt-nc treatment could exert cytostatic action by inhibiting the growth of human promyelocytic leukemia HL60 and human gastric adenocarcinoma-derived NUGC-4 cells; however, no effect was observed in normal human embryo fibroblast OUMS-36 cells by the temporary exposure. These findings indicate that combined treatment with H2 and Pt-nc may act selectively in tumor cells compared with normal cells. Additionally, combined treatment with H2 and Pt-nc resulted in an approximately 200-fold increase in intracellular ROS levels compared with the control, whereas the suppressive effect of tumor cell growth was abrogated entirely by catalase treatment in NUGC-4 cells. Furthermore, combined treatment with H2 and Pt-nc induced hydrogen peroxide generation, cellular morphological changes, cell death, and a decline in DNA synthesis-positive cells. In conclusion, combined treatment with H2 and Pt-nc can induce carcinostatic/carcinocidal effects through intracellular ROS increase, morphological changes, cell death, and DNA synthesis suppression in the human tumor cell line.

Protective Effects of Polyvinylpyrrolidone-Wrapped Fullerene Against Nitric Oxide/Peroxynitrite-Induced Cellular Injury in Human Skin Keratinocytes.

Excess ultraviolet (UV) exposure accelerates skin inflammation, melanogenesis, wrinkle formation, photoaging, and carcinogenesis through oxidative stress and deoxyribonucleic acid damage. These deleterious effects to skin are closely associated with UV-induced reactive oxygen species (ROS) and reactive nitrogen species (RNS) produced via nitric oxide (NO·) generation. RNS are known to be responsible for various skin disorders, such as erythema, melanin production, reduced barrier function, and psoriasis. These skin disorders are major cosmetic problems; RNS control, in addition to ROS control, is important for maintaining healthy skin. In the present study, we investigated the cytoprotective effects of polyvinylpyrrolidone-entrapped fullerene (C60/PVP), a water-soluble ROS scavenger, against nitric oxide (NO·) and peroxynitrite (ONOO-)-induced human keratinocyte injuries. Protective effects of C60/PVP on NO·/ONOO--induced cellular damage and intracellular ONOO- generation were evaluated using a NO· donor S-nitroso-N-acetylpenicillamine (SNAP) in human skin epidermal HaCaT keratinocytes. Furthermore, the suppressive effect of C60/PVP on UVB-induced generation of intracellular ONOO- levels was also investigated. C60/PVP exerted suppressive effects on intracellular increases in NO·-induced ONOO- generation and subsequent cellular damage. Additionally, C60/PVP significantly decreased the UVB-induced generation of intracellular ONOO- levels. These findings suggest that C60/PVP could be useful as a cosmetics ingredient for prevention of skin injuries and/or dysfunction from NO·/ONOO--induced effects in human skin keratinocytes.

Fullerene-polyvinylpyrrolidone clathrate localizes in the cytoplasm to prevent Ultraviolet-A ray-induced DNA-fragmentation and activation of the transcriptional factor NF-kappaB.

By Western blot and immunostaining we proved that polyvinylpyrrolidone (PVP)-wrapped fullerene molecules (PVP-fullerene) could combine the 8- and 53-kb proteins which localize in the membrane of human skin keratinocytes HaCaT. Only fullerene molecules are able to cross the lipid membrane and conjugate 53-kb proteins in the cytosol. There are no fullerene molecules detectable in the nucleus or cytoskeleton. Ultraviolet-A (UVA)-irradiation on HaCaT or normal human epidermal melanocytes (NHEM) caused nuclear fragmentations, lowering of intracellular DNA-contents below diploidy, concurrently with the repressed DNA synthesis and the increased DNA-3'OH cleavage terminals, all of which were repressed by PVP-fullerene, as shown by flow cytometry and PI- or TUNEL-stain fluorography. Translocation of the transcriptional factor NF-kappaB in the cytoplasm to the nucleus of the keratinocytes was caused with UVA and repressed by PVP-fullerene with cytoprotective effects. Thus, the PVP-fullerene may be developed as a UV-protective agent with DNA-preservative effects owing to its combinative ability to molecules in the cytoplasm and cytomembrane, and then represses cellular oxidative stress and blocks abnormal signal pathways.

Clinical evaluation of fullerene-C60 dissolved in squalane for anti-wrinkle cosmetics.

Highly purified and organic solvent-free fullerene-C60 was dissolved, at nearly saturated concentration of 278 ppm, in squalane prepared from olive oil, which is designated as LipoFullerene (LF-SQ) and was examined for usage as a cosmetic ingredient with antioxidant ability. The aim of this study was to assess the anti-wrinkle formation efficacy of LF-SQ in subjects. A total of 23 Japanese women (group I: age 38.9 +/- 3.8, n = 11, group II; age 39.4 +/- 4.3, n = 12) were enrolled in an 8-week trial of LF-SQ blended cream in a randomized, matched pair double-blind study. The LF-SQ cream was applied twice daily on the right or left half of the face, and squalane blended cream (without fullerene-C60) was applied as the placebo on another half of the face. As clinical evaluations of wrinkle grades, visual observation and photographs, and silicone replicas of both crow's feet areas were taken at baseline (0 week) and at 4th and 8th weeks. Skin replicas were analyzed using an optical profilometry technique. The wrinkle and skin-surface roughness features were calculated and statistically analyzed. Subsequently, trans-epidermal water loss (TEWL), moisture levels of the stratum corneum, and visco-elasticity (suppleness: RO and elasticity: R7) were measured on cheeks by instrumental analysis. LF-SQ cream enhanced the skin moisture and the anti-wrinkle formation. LF-SQ cream that was applied on a face twice daily was not effective at 4th week, but significantly more effective than the placebo at 8th week (p < 0.05) without severe side effects. The roughness-area ratio showed significant improvement (p < 0.05) at 8th week with LF-SQ cream as compared to 0 week with LF-SQ cream, but no significant difference was detected between LF-SQ cream and the placebo. We suggest that LF-SQ could be used as an active ingredient for wrinkle-care cosmetics.