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Friedreich’s ataxia is an autosomal recessive disorder characterized by impaired mitochondrial function, resulting in oxidative stress. In this study, we aimed at evaluating whether tocotrienol, a phytonutrient that diffuses easily in tissues with saturated fatty layers, could complement the current treatment with idebenone, a quinone analogue with antioxidant properties. Five young Friedreich’s ataxia patients received a low-dose tocotrienol supplementation (5 mg/kg/day), while not discontinuing idebenone treatment. Several oxidative stress markers and biological parameters related to oxidative stress were evaluated at the time of initiation of treatment and 2 and 12 months post-treatment. Some oxidative stress-related parameters and some inflammation indices were altered in Friedreich’s ataxia patients taking idebenone alone and tended to be normal values following tocotrienol supplementation; likewise, a cardiac magnetic resonance study showed some improvement following one-year tocotrienol treatment. The pathway by which tocotrienol affects the Nrf2 modulation of hepcidin gene expression, a peptide involved in iron handling and in inflammatory responses, is viewed in the light of the disruption of the iron intracellular distribution and of the Nrf2 anergy characterizing Friedreich’s ataxia. This research provides a suitable model to analyze the efficacy of therapeutic strategies able to counteract the excess free radicals in Friedreich’s ataxia, and paves the way to long-term clinical studies. Impact statement Oxidative stress is involved in the pathogenesis of Friedreich's ataxia (FRDA), a genetic disorder causing neurodegeneration due to the dramatic reduction in the expression of frataxin. To date, no cure is available for FRDA patients. In some countries, FRDA patients assume idebenone in order to counteract the effects of frataxin deficiency. We demonstrate that idebenone treatment alone is not able to abrogate oxidative stress in FRDA patients, whereas the combined treatment with tocotrienols might be more efficient and perhaps produce clinical improvement. In fact, a decrease in oxidative stress and inflammation markers can be seen after two months and is more pronounced after one year of treatment. This is, in our opinion, valuable information for clinicians, since idebenone is the treatment of choice for FRDA patients in some countries.

In the search for scaffolds for multifunctional compounds we investigated the structure activity relationship of a class of benzimidazole derivatives bearing 5-membered ring. The newly synthesized and the already known compounds were divided into three classes that present different substituent at 5 position of the benzimidazole ring (-H, -COOH or &ndash, SO3H) and different heterocycle at position 2 (thiophene, furan or pyrrole). All the derivatives were synthesized and tested to determine their photoprotective profile against UV rays, in vitro antioxidant capacity against different radicals (DPPH and FRAP test), antifungal inhibitory activity (dermatophytes and Candida albicans), antiviral and antiproliferative activity. A Structure-Activity Relationship study indicated compound 10, bearing a pyrrole heterocycle on the benzimidazole ring, as the best multifunctional derivative of the series and as potential candidate for the development of drugs especially in case of melanoma.

Three series of arylbenzimidazole derivatives 3–40, 45 have been simply synthesized and tested for their antioxidant capacity. The 2-arylbenzimidazoles were tested against various radicals by the DPPH, FRAP and ORAC tests and showed different activity profiles. It has been observed that the number and position of the hydroxy groups on the 2-aryl portion and the presence of a diethylamino group or a 2-styryl group are related to a good antioxidant capacity. Furthermore, benzimidazoles showed satisfactory SPF values ​​in vitro compared to the commercial PBSA filter, proving to have a good photoprotective profile. In particular, 2-arylbenzimidazole-5-sulphonic acids 15 and 38, the 2-styryl-benzimidazole 45 showed broad spectrum solar protection against UVA and UVB rays. The antiproliferative effect of the benzimidazoles was tested on human skin melanoma Colo-38 cells. The styrylbenzimidazole 45 exhibited antiproliferative effect at low micromolar concentration against Colo-38 cells and very low antiproliferative activity on normal HaCat keratinocyte cells.

Aim: We compared the performances of two different commercial products both based on betamethasone and an antibiotic but using different pharmaceutical vehicles: a polymer and lipid-enriched cream and a conventional oil-in-water emulsion. Methodology: Evaluation was conducted on a reconstructed human epidermis model. Moreover, skin barrier properties and cutaneous hydration of the two vehicles were evaluated on 20 human healthy volunteers. Results: Overall, the polymer and lipid-enriched formulation works as a film-forming product that retains the therapeutic agent for a long time, ensuring its penetration and absorption through the skin, and promoting skin hydration. Conclusion: The above characteristics are useful in the clinical setting, especially in the context of eczematous diseases with a strong xerotic component.

Ultraviolet (UV) light is the most abundant and significant modifiable risk factor for skin cancer and many other skin diseases such as early photo-aging. Across the solar radiation spectrum, UV light is the main cause behind skin problems. In the search for novel photoprotective compounds, a new series of 8-substituted purines were synthesized from commercially available 6-hydroxy-4,5-diaminopyrimidine hemisulfate or 4,5-diaminopyrimidine. All title compounds were investigated for their UV filtering, antioxidant, antifungal, and antiproliferative activities. For the photoprotection assays we used a diffuse transmittance technique to determine the sun protection factor (SPF) in vitro, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric ion reducing antioxidant power (FRAP) tests for evaluating the antioxidant activity of the more potent compounds. Among them, 8-(2,5-dihydroxyphenyl)-7H-purin-6-ol (compound 26) proved to be a good radical scavenger and is also endowed with broad-spectrum UVA filtering capabilities, suitable for further development as a protective molecule.

Over the last years, hyaluronic acid (HA) injectable dermal fillers (DFs) have become the most popular agents for soft tissue contouring and volumizing. HA fillers are characterized by most of the properties that an ideal DF should have, due to HA unique chemical-physical properties, biocompatibility, biodegradability, and versatility. Therefore, HA DFs have revolutionized the filler market with a high number of products, which differ in terms of HA source, cross-linkage (agent and degree), HA concentration, hardness, cohesivity, consistency, inclusion or lack of anesthetic, indication, and longevity of correction. The article first provides a general introduction to DF world, and an overview of the different materials is available for fillers. Second, it describes the characteristics and the peculiarities of HA fillers, their differences from the other available materials, and therefore the reasons at the base of their success. Moreover, an update regarding the main Food and Drug Administration (FDA) approved fillers is presented.

An ever-increasing incidence of skin neoplastic diseases is registered. Therefore, it is important to protect the skin from the UV radiation that reaches the epidermis and dermis but also to block ROS generated by them. Our attention was attracted in developing new compounds provided with both UV filtering and antioxidant capacities. To this end, 2-phenyl-1H-benzimidazole-5-sulfonic acid (PBSA), a known UV filter, was selected as lead compound for its lack of antioxidant activity, high water solubility and good safety profile. PBSA was sequentially modified introducing hydroxyls on the phenyl ring and also substituting the functional group in position 5 of the benzimidazole ring. At the end of the synthetic study, a new, very potent class of antioxidants has been obtained. Surprisingly some of the developed molecules, while devoid of significant UV-filtering activity was endowed with potent UV-filtering booster capability if associated with known commercial UVB and UVA filters.

Two series of indole derivatives 4-17, 20-22 were easily prepared and assayed for their radical-scavenging ability. Arylidene-1H-indole-2-carbohydrazones showed different extent antioxidant activity in DPPH, FRAP and ORAC assays. Good antioxidant activity is related to the number and position of hydroxyl groups on the arylidene moiety as well as to the presence of methoxy or 4-(diethylamino) group. On the contrary low antioxidant activity is showed by the isomeric 1H-indol-2-yl(methylene)-benzohydrazides. Furthermore, hydrazones 4-17 showed photoprotective capacities with satisfactory in vitro SPF as compared to the commercial PBSA sunscreen filter. The indole 16 and 17, showing the best antioxidant and photoprotective profile, were included in different formulation and their topical release was evaluated. Varying the formulation composition, it was possible to optimize skin adsorption and solubility of the active indole in the formulation. The antiproliferative effect of the hydrazones 4-17 was tested on human erythroleukemia K562 and melanoma Colo-38 cells. Hydrazones 11, 16 and 17 showed growth inhibition at sub micromolar concentrations on both cell lines. These results indicate indole hydrazones as potential multifunctional molecules especially in the treatment of neoplastic diseases being the good antioxidant properties of 16 and 17 correlated to their high antiproliferative activity.

The incidence of skin cancer is increasing both because of climate change and the increase in pollution than people&rsquo, s incorrect habits of sun exposure. In these regards, sunscreen and photoprotection are essential tools in consenting the benefits induced by safe solar light exposition and skin cancer prevention. In this work, a new class of sunscreen filter was synthesized by chemical combination of a physical filter (ZnO) and Oxisol (dihydroxyphenyl benzimidazole carboxylic acid), an antioxidant molecule with booster effect. In this work, a new class of filters with new properties was achieved by direct functionalization of particles surface. A full characterization of this multifunctional ingredient (ZnO&ndash, Ox) was conducted: Compared with the simple mixture, the new filter acts as a multifunctional molecule showing a higher Sun Protection Factor (SPF), a better cytotoxic profile (MTT and NRU assay), and anti-acne activity. A strong reduction of photocatalytic activity of ZnO was observed, also improving the safety profile.

Objective The in vitro evaluation of SPF is still a problem due to the lack of repeatability and correlation between the in vitro and in vivo data and many authors are currently working to develop an internationally harmonized method.(1) Very recently, the use of several “adjuvant” ingredients such as boosters, antioxidants, immuno-modulators, solvents and film forming ingredients have further complicated the pattern for product developers, that should frequently run in vivo test. The aim of this study is to understand if a simple and cheap in vitro method could be optimized in order to provide both statistically repeatable and predictive SPF measurement. Methods In vitro SPF assessments were carried out on 75 commercial products. The SPF was measured according to two laboratory methods (A and B), using different substrates (PMMA and surgical tape Transpore™), quantity of product, spectrophotometers. In order to evaluate if a standard technique of spreading could lead to a statistically reliable result, we applied different spreading pressure (100 g and 200 g). Furthermore, we investigate if other parameters characterizing the product (SPF Category, Filter and Texture) might represent statically significant variables affecting the measures. We then compared the results obtained from in vitro SPF measure of 11 products to in vivo SPF, in order to assess the predictivity of in vitro methods. Results Several problems were encountered in confirming the weakness of the in vitro procedures. Pressure, SPF Category, Filter and Texture did not affect significantly the results. Overall best results were obtained with the B2 method that in terms of repeatability and predictivity provided statistically better results. Method A with Transpore™ tape showed better in vitro-in vivo correlation than Method B with PMMA plates. Conclusion In our investigation we demonstrated that it is possible for a single laboratory to optimize internal methods and protocols to achieve repeatable and predictive in vitro results, but it is extremely difficult to develop methods reproducible and equally reliable in different laboratories, probably due to “external variables” (eg. environmental, operator), which are difficult to control. This article is protected by copyright. All rights reserved.

Oxidative stress is the product or aetiology of various multifactorial diseases; on the other hand, the development of multifunctional compounds is a recognized strategy for the control of complex diseases. To this end, a series of benzothiazole derivatives was synthesized and evaluated for their multifunctional effectiveness as antioxidant, sunscreen (filter), antifungal and antiproliferative agents. Compounds were easily synthesized via condensation reaction between 2-aminothiophenols and different benzaldehydes. SAR study, particularly in position 2 and 6 of benzothiazoles, led to the identification of 4g and 4k as very interesting potential compounds for the design of multifunctional drugs. In particular, compound 4g is the best blocker of hERG potassium channels expressed in HEK 293 cells exhibiting 60.32% inhibition with IC50 = 4.79 μM.

Iran has a rich and diverse cultural heritage, consisting of a complex traditional medicine deeply rooted in the history of the territory that goes back to the Assyrian and Babylonian civilizations. The ethnomedical practices that can be identifiable nowadays derive from the experience of local people who have developed remedies against a wide range of diseases handing down the knowledge from generation to generation over the millennia. Traditional medicine practices represent an important source of inspiration in the process of the development of new drugs and therapeutic strategies. In this context, it is useful to determine the state of the art of ethnomedical studies, concerning the Iranian territory, and of scientific studies on plants used in traditional Iranian medicine. Data regarding 245 plants used in Iranian ethnomedical practices and scientific studies conducted on 89 plants collected in the Iranian territory have been reported. All of the scientific studies here reported draw inspiration from traditional medicine. The World Health Organization (WHO) has repeatedly called for an intensification of the scientific validation processes of traditional medicines intended as an important contribution to public health in various parts of the world. The process of study and validation of Iranian ethnomedical practices appears to be at an early stage.

Moringa oleifera has gained increasing popularity as a food supplement but not in the pharmaceutical and cosmetic area. The aim of this study was the preparation, characterization, and evaluation of extracts from the leaves of Moringa oleifera as a herbal sun care phytocomplex. Three different extracts of Moringa oleifera leaves, from Senegal, have been prepared and chemically characterized in the phenolic fraction by HPLC-DAD and Folin–Ciocalteu test. To explore photoprotective properties, an extensive evaluation of UV filtering, antioxidant (DPPH, FRAP, ORAC, PCL), and anti-hyperproliferative (human melanoma Colo38 cells) capacities have been conducted. Furthermore, a formulation study regarding cosmetic prototypes has been carried out in order to determine the Sun Protection Factor (SPF), which was assessed in vitro. The extracts were demonstrated to confer significant values of protection, with an SPF 2, that corresponds to a 50% protection against UV-B rays, at concentrations as low as 2% to 4%. Finally, the evaluation on potential irritation of the finished formulations was conducted by Patch Test and no significant irritant potential was observed. These evidence enlarged the already significant number of activities and potential uses of this plant, which is well-known for its importance in the medicinal and nutritional fields.

New benzofuranhydrazones 3–12 were easily prepared and assayed for their radical-scavenging ability. Hydrazones 3–12 showed different extent antioxidant activity in DPPH, FRAP and ORAC assays. Good antioxidant activity is related to the number and position of hydroxyl groups on the arylidene moiety. High antioxidant activity is showed by the 2-hydroxy-4-(diethylamino)benzylidene derivative 11. Furthermore, hydrazones 3–12 showed photoprotective capacities with satisfactory in vitro SPF as compared to the commercial PBSA sunscreen filter. The antiproliferative effects of the hydrazones 3–12 was tested on erythroleukemia K562 and Colo-38 melanoma human cells. All the compounds showed growth inhibition in the micromolar to sub micromolar concentration range. If taken together these results points to benzofuran hydrazones as potential multifunctional molecules especially in the treatment of neoplastic diseases being the good antioxidant properties of 5, 7 and 11 correlated to their high antiproliferative activity.

Recent interest in flavonoids has increased greatly due to their biological and pharmacological activities. Flavonoids, consist of a large group of low molecular weight polyphenolic substances, naturally occurring in fruits, vegetables, tea, and wine, and are an integral part of the human diet. Rutin is a common dietary flavonoid that is widely consumed worldwide from plant-derived beverages and foods as traditional and folk medicine remedy as well. Rutin exhibit important pharmacological activities, including anti-oxidation, anti-inflammation, anti-diabetic, anti-adipogenic, neuroprotective and hormone therapy. Here, we present the synthesis, antimicrobial, antiproliferative and pro-apoptotic effect on human leukemic K562 cells of compound R2, a new semi-synthetic derivative of Rutin as compared to Rutin itself. The new derivative was also included in finished topical formulations to evaluate a potential application to the dermatology field in view of the antioxidant/antimicrobial/antiinflammatory properties. Stability studies were performed by HPLC; PCL assay and ORAC tests were used to determine the antioxidant activity. R2 presented an antioxidant activity very close to that of the parent Rutin while bearing much better lipophilic character. Regarding antiproliferative effects on the human K562 cell line, R2 was found to be more effective than parent Rutin. Preliminary experiments demonstrated that R2 inhibits NF-kB activity and promotes cellular apoptosis.

Ethnopharmacological relevance The genus Hedyosmum (family: Chloranthaceae) represents an interesting source of natural active compounds, and the 45 species of this genus are widespread in Central and South America and to a lesser extent Southeast Asia (southern China and western Malaysia). Several species are traditionally used in folk medicine. However, the data made available in recent years have not been organized and compared. Aim of this review The present study is a critical assessment of the state-of-the-art concerning the traditional uses, the phytochemistry and the pharmacology of species belonging to the genus Hedyosmum to suggest further research strategies and to facilitate the exploitation of the therapeutic potential of Hedyosmum species for the treatment of human disorders. Materials and methods The present review consists of a systematic overview of scientific literature concerning the genus Hedyosmum published between 1965 and 2018. Moreover, an older text, dated from 1843, concerning the traditional uses of H. bonplandianum Kunth has also been considered. Several databases (Francis & Taylor, Google Scholar, PubMed, SciELO, SciFinder, Springer, Wiley, and The Plant List Database) have been used to perform this work. Results Sixteen species of the genus Hedyosmum have been mentioned as traditional remedies, and a large number of ethnomedicinal uses, including for the treatment of pain, depression, migraine, stomach-ache and ovary diseases, have been reported. Five species have been used as flavouring agents, tea substitutes or foods. Sesterterpenes, sesquiterpene lactones, monoterpenes, hydroxycinnamic acid derivatives, flavonoids, and neolignans have been reported as the most important compounds in these species. Studies concerning their biological activities have shown that members of the Hedyosmum genus possesses promising biological properties, such as analgesic, antinociceptive, antidepressant, anxiolytic, sedative, and hypnotic effects. Preliminary studies concerning the antibacterial, antioxidant, antiplasmodial, and antifungal activities of these plants as well as their cytotoxic activities against different tumour cell lines have been reported. Some active compounds from the Hedyosmum genus have been used as starting points for the innovative and bioinspired development of synthetic molecules. A critical assessment of these papers has been performed, and some conceptual and methodological problems have been identified regarding the materials and methods and the experimental design used in these studies, including a lack of ethnopharmacological research. Conclusions The present review partially confirms the basis for some of the traditional uses of Hedyosmum species (mainly H. brasiliense) through preclinical studies that demonstrated their antinociceptive and neuroprotective effects. Due to promising preliminary results, further studies should be conducted on 13-hydroxy-8,9-dehydroshizukanolide and podoandin. Moreover, several essential oils (EOs) from this genus have been preliminarily investigated, and the cytotoxic and antibacterial activities of H. brasiliense and H. sprucei EOs certainly deserve further investigation. From the promising findings of the present analysis, we can affirm that this genus deserves further research from ethnopharmacological and toxicological perspectives.

Besides the unquestionable positive effects of solar exposure for human health, UV rays have been widely investigated for toxicology aspects related to excessive UVB and UVA doses, which involve sunburns, skin aging, DNA skin damage and tumorigenesis. At present, synthetic and mineral sunscreens are used to protect against these damages but several natural molecules can provide UV protection, including also synergic effect or enhanced photo stability. Although a large number of herbal extracts and plant origin molecules can deserve potential applications, most of the study reported utilizes different method and different strategies of investigation, making thus difficult to understand the real versus claimed potential. This is possibly one of the reasons why, beside the large body of literature there are no officially approved natural commercial sun-filter but a consistent number of commercially available solar products (sunscreen) on the market that contain herbal derivatives. In this review we have evaluated the papers appeared in the last 15years and we have critically collected the most significant data. Several databases, namely Scifinder, Pubmed, Google Scholar, ISI-Web of Science and Scopus, were used as literature sources; excluding patents and symposium or congress papers. Only articles in the English language have been selected. New formulation, new skin delivery systems, skin penetration enhancers and boosters are most likely the next frontier of investigation in order to better understand the role of whole herbal extracts in exerting their photo protective activity.

We here report the results of our investigations carried out on verbascoside, a phenylpropanoid glycoside known for its antioxidant, anti-inflammatory and photoprotective actions. Verbascoside was obtained from Buddleia davidii meristematic cells, obtained in turn using a sustainable biotechnology platform which employs an in vitro plant cell culture technology. Verbascoside was first investigated to assess the behaviour of the active ingredient in solution or in finished preparations, in view of its potential topical use, especially in skin protection. Stability studies were performed by HPLC, and a PCL assay was adopted to determine the radical scavenging activity toward superoxide anion. The high hydrophilic character of verbascoside, suggested in a somewhat limited range of possible applications, leading us to explore its derivatization to obtain the semi-synthetic derivative VPP, an acyl derivative of verbascoside, with an improved range of applications due to its lower hydrophilic profile. Alone, VPP revealed increased antioxidant activity, both as an active ingredient and in dermocosmetic preparations. Stability studies showed a greater stability of VPP in lipophilic vehicles, whereas the parent verbascoside proved more stable in an O/W emulsions. Verbascoside was also stable in suppositories, an interesting pharmaceutical form for possible applications in treatment of inflammation of the intestinal mucosa.

Chemical fingerprinting of commercial Pelargonium capitatum (Geraniaceae) essential oil samples of south African origin was performed by GC, GC/MS, and (13) C- and (1) H-NMR. Thirty-seven compounds were identified, among which citronellol (32.71%) and geraniol (19.58%) were the most abundant. NMR Spectra of characteristic chemicals were provided. Broad-spectrum bioactivity properties of the oil were evaluated and compared with those of commercial Thymus vulgaris essential oil with the aim to obtain a functional profile in terms of efficacy and safety. P. capitatum essential oil provides a good performance as antimicrobial, with particular efficacy against Candida albicans strains. Antifungal activity performed against dermatophyte and phytopathogen strains revealed the latter as more sensitive, while antibacterial activity was not remarkable against both Gram-positive and Gram-negative bacteria. P. capitatum oil provided a lower antioxidant activity (IC(50) ) than that expressed by thyme essential oil, both in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and β-carotene bleaching tests. Results in photochemiluminescence (PCL) assay were negligible. To test the safety aspects of P. capitatum essential oil, mutagenic and toxicity properties were assayed by Ames test, with and without metabolic activation. Possible efficacy of P. capitatum essential oil as mutagenic protective agent against NaN(3) , 2-nitrofluorene, and 2-aminoanthracene was also assayed, providing interesting and significant antigenotoxic properties.

Although the metabolism of vitamin E has been extensively studied in cell culture, animals, and humans, biochemical analyses of intermediate metabolites are scarce. We here describe the synthesis and proapoptotic properties of long-chain metabolites of α- and δ-tocopherol. Several long-chain vitamin E metabolites, namely 13'-hydroxy- and 13'-carboxychromanols, were synthesized from garcinoic acid, a δ-tocotrienol derivative extracted from the African bitter nut Garcinia kola. Both α- and δ-13'-carboxychromanol induced cell death in HepG2 cells at EC(50) of 13.5 and 6.5 μM, respectively. Apoptosis was quantified by annexin V/7-AAD staining and flow cytometry analysis. By immunoblot analyses, we observed activation of both caspase-3 and caspase-9 as well as PARP-1 cleavage. Parameters of mitochondrial dysfunction including reduced mitochondrial membrane potential and increased intracellular and intramitochondrial reactive oxygen species formation were observed after metabolite treatment. Last, long-chain hydroxychromanols were readily metabolized to the corresponding carboxychromanols in HepG2 cells. Taken together, these results indicate that long-chain metabolites may be responsible for antiproliferative properties of vitamin E vitamers.

Both amyloid-β (Aβ) and transition metal ions are shown to be involved in the pathogenesis of Alzheimer’s disease (AD), though the importance of their interactions remains unclear. Multifunctional molecules, which can target metal-free and metal-bound Aβ and modulate their reactivity (e.g., Aβ aggregation), have been developed as chemical tools to investigate their function in AD pathology; however, these compounds generally lack specificity or have undesirable chemical and biological properties, reducing their functionality. We have evaluated whether multiple polyphenolic glycosides and their esterified derivatives can serve as specific, multifunctional probes to better understand AD. The ability of these compounds to interact with metal ions and metal-free/-associated Aβ and further control both metal-free and metal-induced Aβ aggregation was investigated through gel electrophoresis with Western blotting, transmission electron microscopy, UV-Vis spectroscopy, fluorescence spectroscopy and NMR spectroscopy. We also examined the cytotoxicity of the compounds and their ability to mitigate the toxicity induced by both metal-free and metal-bound Aβ. Of the polyphenols investigated, the natural product (Verbascoside) and its esterified derivative (VPP) regulate the aggregation and cytotoxicity of metal-free and/or metal-associated Aβ to different extents. Our studies indicate Verbascoside represents a promising structure for further multifunctional tool development against both metal-free Aβ and metal-Aβ.

BACKGROUND/PURPOSES Skin antioxidant network protects cells against oxidative injury and prevents the production of oxidation products. When oxidative stress overwhelms the skin antioxidant capacity, the subsequent modification of the cellular redox apparatus leads to an alteration of cell homeostasis leading to degenerative processes. In the dermocosmetic field, the topical application of antioxidants is often suggested as a possible strategy to prevent and modulate oxidative skin damages. Continuing our studies addressed to set-up new bio-engineering protocols for the claim substantiation of antioxidant cosmetic products, we have developed a new non-invasive methodology for the evaluation of antioxidants cosmetics ingredients and finished products. METHODS The effects of a pre-treatment on forearm skin with an antioxidant ingredient were investigated on 15 volunteers, in a double-blind randomised fashion. A non-invasive method was devised that comprises the collection of forehead SC layers of the pre-treated area and control and the next evaluation of skin antioxidant capacity (IAC-S) by a luminescence-based method. RESULTS The results showed that the antioxidant preparation was able to increase, to a statistically significant extent (P

Living beings have evolved over the past two billon years through adaptation, to an increasing atmospheric oxygen concentration, by both taking advantage of oxygen activating function and developing a complex control network. In these regards, potentially damaging species (reactive oxygen, nitrogen and chlorine species) arise as by-products of metabolism and also work as physiological mediators and signalling molecules. Oxidative stress may be an important factor in numerous pathological conditions, i.e. infection if micronutrient s are deficient. Levels of these species are controlled by the antioxidant defence system, which is composed by antioxidants and pro-antioxidants. Several components of this system are micronutrients (e.g. vitamins C and E), are dependent upon dietary micronutrients (e.g. CuZn and Mn superoxide dismutase) or are produced by specific endogenous pathways. The antioxidant defences act, to control levels of these species, as a coordinated system where deficiencies in one component may affect the efficiency of the others. In this network some of the components act as direct antioxidants whereas others act indirectly (pro- antioxidants) either by modulation of direct agents or by regulation of the biosynthesis of antioxidant proteins. Thus, entities usually not considered as antioxidants, also act efficiently counteracting damaging effects of oxidative species. In this contest, the design of new molecules that take into account synergistic interactions among different antioxidants, could be useful both to address mechanistic studies and to develop possible therapeutic agents. In this review the principal categories of antioxidants and pro-antioxidants that goes from vitamins through phyto-derivatives to minerals, are critically reviewed, with particular emphasis on structure-function considerations, together with the perspective opened, in the design of possible therapeutic agents, by the antioxidants interplay.

Dry eye syndrome is a common disease which can damage the corneal epithelium. It is treated with eye drops to stimulate tear production and hydrate the corneal surface. The most prescribed artificial tear remedies contain hyaluronic acid (HA), which enhances epithelial wound healing, improving tissue health. To the best of our knowledge, only a few recent studies have investigated cross-linked HA (HA-CL) in eye drops for human applications. This work consists in an in vitro evaluation of the re-epithelialization ability of two different preparations containing a recently synthetized HA cross-linked with urea: 0.02% (w/v) HA-CL (solution 1, S1), and 0.4% (w/v) HA-CL (solution 2, S2). The study was conducted on both 2D human corneal cells (HCEpiC) and 3D reconstructed tissues of human corneal epithelium (HCE). Viability by 3(4,5-dimethylthiazol-2)2,5-diphenyltetrazolium bromide (MTT) test, pro-inflammatory cytokine release (interleukin-8, IL-8) by ELISA, and morphology by hematoxylin and eosin (HE) staining were evaluated. In addition, to understand the molecular basis of the re-epithelialization properties, cyclin D1 levels were assessed by western blot. The results showed no cellular toxicity, a slight decrease in IL-8 release, and restoration of epithelium integrity when the wounded 3D model was treated with S1 and S2. In parallel, cyclin D1 levels increased in cells treated with both S1 and S2.

Few muscarinic antagonists differentiate between the M4 and M2 muscarinic receptors. In a structure activity study, aimed at discovering leads for the development of a M4 muscarinic receptor-selective antagonist, we have synthesized and tested at cloned muscarinic receptors the binding of a group of dioxolane- or oxadiazole-dialkyl amines, and compared them to our compound 1, which contains the furan nucleus. Although none of these agents were particularly potent at M4 receptors (Kd values were typically 30-70 nM), furan derivatives (-)1 and (+)1 were significantly more potent at M4 receptors than at M2 receptors (approximately 3- and 4-fold, respectively). The dioxolane derivatives 12b and 12c were more than 10-fold selective for the M4 versus the M2 receptors, while the dioxolane derivative 12e was 15-fold more potent at M4 receptors than for M2 receptors. However, these agents bound to M3 receptors with potencies like that for the M4 receptor, so they are not M4-selective. The M4/M2 relative selectivities of some of our compounds are similar to the better hexahydrosiladifenidol derivatives, and may provide some important structural clues for the development of potent and selective M4 antagonists.

In a dual targeting approach, to explore the ability of tretinoin (all-trans-retinoic acid) to behave as a covalent carrier for cytotoxic entities, conjugates of retinoic acid with a few representative molecules, being important examples of antitumor pharmacophores (i.e., nucleoside analogues and alkylating agents), have been synthesized and tested for their cytostatic and differentiating activity. All compounds were stable to in vitro hydrolysis in human plasma and more lipophilic than the parent compounds, thus consenting enhanced uptake into the cells. Among the nucleoside analogues the Ara-C derivatives 3 and 6 and the Ara-A derivative 7 proved the most cytostatic (IC500.32 microgram/mL) resulting from 25- to144-fold more active (Ara-A derivatives) or at least as equally active (Ara-C derivatives) as compared to the parent nucleosides. Compound 3, endowed with a highly lipophilic silyl moiety at the 3' and 5' positions, showed the highest differentiating activity (54% and 44% differentiated HL-60 cells at 0.2 and 0.05 microgram/mL respectively). With regard to the retinoic acid conjugates of alkylating agents, compound 10 was the most cytostatic agent (IC500.32 microgram/mL) and the most potent differentiating agent (33-34% at 0.32 and 0.08 microgram/mL). These structures may also be regarded as analogs of either retinoic acid or the cytotoxic compound.

Nucleoside derivatives are largely synthesized and tested to investigate their influence on platelet aggregation. It's well known that P2Y receptors play an important role in the regulation of platelet function and, as consequence, in controlling atherothrombotic events. The research of compounds that antagonize P2Y 1 and, in particular, P2Y 12 receptors is of great interest in the aim to obtain platelet aggregation inhibitors that are effective in the prevention and treatment of arterial thrombosis. In this study we present the synthesis and in vitro metabolic stability in human blood and rat liver homogenate of a new class of nucleoside derivatives, in particular 5′-phosphonate adenosine, inosine, guanosine and thioadenosine analogues also modified at the ribose moiety. On the basis of the results obtained we can hypothesize compounds 4 and 18 to have in vivo a relatively high stability.

During a random screening of representative libraries of nucleoside analogues we discovered that the adenine derivatives FEVB28 and FEG118 were Flaviviridae inhibitors endowed with potency comparable, if not superior, to that of ribavirin. Those studies prompted us to design a new class of protected nucleoside analogs, reported herein, which displays interesting anti-bovine viral diarrhea virus (BVDV) activity and low cytotoxicity in cell-based assays (4, 23, 29 EC(50): 14, 11, 26 microM respectively, CC(50)100 microM) and appreciable activity in enzyme assays against the RNA dependent RNA polymerase (RdRp) of BVDV (4, 23, 29, RdRp inhibition activity 27, 16, 15 microM respectively). A molecular modeling study was also carried out to highlight the possible interactions between this compounds class and the corresponding hepatitis C virus (HCV) enzyme.

Friedreich Ataxia (FRDA), the most frequent inherited ataxia, is not only characterized by progressive gait and limb ataxia, but in most cases is also accompanied by a severe hypertrophic cardiomyopathy. This life threatening symptom can be ameliorated by the administration of idebenone, a short chain quinone antioxidant, supporting additional evidence that oxidative stress plays a major role in the pathogenesis of this disease. In this study we analyze the combinatorial effect of different antioxidants on cell viability of FRDA fibroblasts and of RAT-1 immortalized fibroblasts exposed to oxidative stress. We find that an equimolar mixture of idebenone and vitamin E is more potent than each of the compound alone. Increased potency was also obtained with a novel synthetic antioxidant (Fe-Aox29) combining the active groups from both idebenone and vitamin E. These results indicate, that idebenone and vitamin E might act synergistically to counteract oxidative stress in fibroblasts from FRDA patients.

Selective and effective TK2 inhibitors can be obtained by introduction of bulky lipophilic chains (acyl or alkyl entities) at the 2' position of araT and BVaraU, nucleoside analogues naturally endowed with a low TK2 affinity. These derivatives showed a competitive inhibitory activity against TK2 in micromolar range. BVaraU nucleoside analogues, modified on the 2'-O-acyl chain with a terminal N-Boc amino-group, conserved or increased the inhibitory activity against TK2 (7l and 7m IC(50): 6.4 and 3.8 microM, respectively). The substitution of an ester for a carboxamide moiety at the 2' position of araT afforded a consistent reduction of the inhibitory activity (25, IC(50): 480 microM). On the contrary, modifications at 2'-OH position of araC and araG, have provided inactive derivatives against TK2 and dGK, respectively. The biological activity of a representative compound, 2'-O-decanoyl-BVaraU, was also investigated in normal human fibroblasts and was found to impair mitochondrial function due to TK2 inhibition.

Preliminary investigations allowed us to anticipate that conjugation of nipecotic acid with L-ascorbate (AA) gave a prodrug endowed with anticonvulsant activity in mice. In view of these results, and in order to get deepen insight into the molecular aspects at the base of the transport mechanism, a second generation of compounds, based on 6-bromo-6-deoxy-L-ascorbic acid (BrAA) as the carrier molecule was designed and synthesized. Effects of the chirality of the transported drug was also investigated on R- and S-nipecotic acid. Interaction and uptake modalities were evaluated in our in vitro model based on human retinal pigment epithelium cells (HRPE), which expresses the membrane L-ascorbic acid (AA) SVCT2 transporters. A remarkable increase on SVCT2 affinity was found going from AA to BrAA conjugates, that is, 11 (Ki=1187+/-78 microM) versus 19 (Ki=193+/-14 microM) and 12 (Ki=39.8+/-3.2 microM) versus 20, (Ki=7.4+/-0.8 microM). Taken together, these data are in agreement with our initial hypothesis on the possibility to achieve better affinities by conjugation with AA analogs, and also consent to hypothesize the presence of accessory interactions that may improve transporters recognition.

To improve the entry of certain drugs into brain, ascorbic acid (AA) conjugates of these drugs were synthesized and their capacity to interact with SVCT2 ascorbate transporters was explored. Kinetic studies clearly indicate that all of the conjugates were able to competitively inhibit ascorbate transport in human retinal pigment epithelial cells (HRPE). In vivo studies, in a mouse model system, demonstrate that conjugate 3 is better absorbed compared to the nonconjugated parent drug.

Highly selective arabinofuranosyl nucleosides, which inhibit the mitochondrial thymidine kinase (TK-2) without affecting the closely related herpes simplex virus type 1 thymidine kinase (HSV-1 TK), varicella-zoster virus thymidine kinase (VZV-TK), cytosolic thymidine kinase (TK-1) or the multifunctional Drosophila melanogaster deoxyribonucleoside kinase (Dm-dNK), have been obtained. SAR studies indicate a close relation between the length of the substituent at the 2' position of the arabinofuranosyl moiety and the inhibitory activity.

Continuing our studies on ribonucleotide reductase (RNR) mechanism-based inhibitors, we have now prepared the diphosphates (DP) of 2'-O-allyl-1-beta-D-arabinofuranosyl-uracil and -cytosine and 2'-O-allyl-9-beta-D-arabinofuranosyl-adenine and evaluated their inhibitory activity against recombinant murine RNR. 2'-O-Allyl-araUDP proved to be inhibitory to RNR at an IC(50) of 100 microM, whereas 2'-O-allyl-araCDP was only marginally active (IC(50) 1 mM) and 2'-O-allyl-araADP was completely inactive. The susceptibility of the parent nucleosides to phosphorylation by thymidine kinase and 2'-deoxycytidine kinase was also investigated, and all nucleosides proved to be poor substrates for the above-cited kinases. Moreover, prodrugs of 2'-O-allyl-araU and -araC monophosphates, namely 2'-O-allyl-5'-(phenylethoxy-L-alanyl phosphate)-araU and -araC, were prepared and tested against tumor cell proliferation but proved to be inactive. A molecular modeling study has been conducted in order to explain our results. The data confirm that for both the natural and analogue nucleoside diphosphates, the principal determinant interaction with the active site of RNR is with the diphosphate group, which forms strong hydrogen bonds with Glu623, Thr624, Ser625, and Thr209. Our findings indicate that the poor phosphorylation may represent an explanation for the lack of marked in vitro cytostatic activity of the test compounds.

Pig liver esterase (EC 3.1.1.1) catalysed regioselective hydrolysis of 1-(2,3,5-tri-O-acyl-β-D-arabinofuranosyl)uracil, -cytosine and -adenine to give the corresponding 2′-monoesters effectively and in high yield. This methodology enabled the preparation of 1-(2-O-acyl-β-D-arabinofuranosyl)-5-[( E)-(2-bromovinyl)]uracil prodrugs which, although slightly less active than the parent 1-(β-D-arabinofuranosyl)-5(E)-(2 bromovinyl)uracil (sorivudine; BV-araU), were strongly active in vitro against varicella-zoster virus (ED50 2.4–45 ng/ml). The retarded rates of enzymatic hydrolysis of the 2′-esters imply that they might function as lipophilic prodrugs, leading to increased plasma and cellular concentrations. In view of the marked in vitro activity, they represent an interesting approach to arabinofuranosyl nucleoside prodrugs with improved pharmacokinetics and enzymatic stability.