Determination of sun protection factor and antioxidant properties of six Chilean Altiplano plants

In the present study, we investigated sun protection factor and antioxidant properties of Parastrephia lepidophyla Cabr., Fabiana squamata Phil., Ephedra chilensis K.Presl., Lampaya medicinalis Phil., Baccharis tola Phil., and Azorella compacta Phil. The ethanol extracts were tested regarding their in vitro free radical scavenger ability and sun protection factor (SPF). Due to its antioxidant and photoprotective properties, B. tola is a promising candidate for use in cosmetic formulations. To evaluate the regenerative capacity of the B. tola extract, the planarian regeneration assay (Dugesia tigrina) was performed. Identification of phenolic compounds in B. tola, was performed by HPLC-ESI-MS/MS. Based on freeze-dried extracts of B. tola, a facial cream and a biphasic lotion with repairing tip action were formulated. These two formulations were evaluated by additional assays including organoleptic tests, measurement of pH, centrifugation and patch test to check a potential hypersensitivity (skin irritation) which can be induced by the products as well as a sensory survey. Stability studies, carried out over 12 months, prove that formulations were stable over time. It can be concluded that both products are innovative and shown solar protection, antioxidant and regenerative properties

Precision-Cut Liver Slices of Salmo salar as a tool to investigate the oxidative impact of CYP1A-mediated PCB 126 and 3-methylcholanthrene metabolism

a b s t r a c t Fish isolated cell systems have long been used to predict in vivo toxicity of man-made chemicals. In present study, we tested the suitability of Precision-Cut Liver Slices (PCLS) as an alternative to these models that allows the evaluation of a global tissue response to toxicants, to investigate oxidative stress response to cytochrome P450 1A (CYP1A) induction in fish liver. PCLS of Salmo salar were exposed for 21 h to increasing doses of 3-methylcholanthrene (3-MC) and Polychlorobiphenyl 126 (PCB 126). 3-MC (25 lM) strongly induced CYP1A transcription. In dose-response analysis (25-100 lM), EROD activity was strongly increased at intermediate 3-MC concentrations. We found the counter-intuitive decline of EROD at the highest 3-MC doses to result from reversible competition with ethoxyresorufin. No increases of H 2 O 2 production, antioxidant enzymes activities or oxidative damage to lipids were found with 3-MC treatments. PCLS subjected to PCB 126 (2-200 nM) showed increased contamination levels and a parallel increased CYP1A mRNA synthesis and EROD activity. H 2 O 2 production tended to increase but no oxidative damage to lipids was found. As antioxidant enzymes activities declined at the highest PCB 126 dose, it is suggested that longer incubation periods could be required to generate oxidative stress in PCLS

Chemical composition and antimicrobial activity of essential oil of peruvian Dalea strobilacea Barneby

Dedicado en homenaje al Dr. Isidoro Manuel Sánchez Vega (Moche 1938 – Lima 2015).The composition of the essential oil obtained by hydrodistillation from Dalea strobilacea Barneby (Fabaceae) aerial parts was examined by GC and GC/MS. β-Phellandrene (44%) together with α-pinene (18%) were the main essential oil components. Antimicrobial activity of the essential oil was evaluated against eight bacterial strains. A moderate growth inhibition of Klebsiella pneumoniae, Staphylococcus aureus and Enterococcus faecalis was shown by the essential oil.  

Restoring Specific Lactobacilli Levels Decreases Inflammation and Muscle Atrophy Markers in an Acute Leukemia Mouse Model

The gut microbiota has recently been proposed as a novel component in the regulation of host homeostasis and immunity. We have assessed for the first time the role of the gut microbiota in a mouse model of leukemia (transplantation of BaF3 cells containing ectopic expression of Bcr-Abl), characterized at the final stage by a loss of fat mass, muscle atrophy, anorexia and inflammation. The gut microbial 16S rDNA analysis, using PCR-Denaturating Gradient Gel Electrophoresis and quantitative PCR, reveals a dysbiosis and a selective modulation of Lactobacillus spp. (decrease of L. reuteri and L. johnsonii/gasseri in favor of L. murinus/animalis) in the BaF3 mice compared to the controls. The restoration of Lactobacillus species by oral supplementation with L. reuteri 100-23 and L. gasseri 311476 reduced the expression of atrophy markers (Atrogin-1, MuRF1, LC3, Cathepsin L) in the gastrocnemius and in the tibialis, a phenomenon correlated with a decrease of inflammatory cytokines (interleukin-6, monocyte chemoattractant protein-1, interleukin-4, granulocyte colony-stimulating factor, quantified by multiplex immuno-assay). These positive effects are strain- and/or species-specific since L. acidophilus NCFM supplementation does not impact on muscle atrophy markers and systemic inflammation. Altogether, these results suggest that the gut microbiota could constitute a novel therapeutic target in the management of leukemia-associated inflammation and related disorders in the muscle

AD 5, a dehydroalanine derivative, decreases the amount of reactive oxygen species formed during nitrofurantion microsomal metabolism.

N-acyl dehydroalanines have been shown to react with and scavenge oxygen derived free radicals. One of those compounds, the AD-5 (N-(paramethoxyphenylacetyl) dehydroalanine) has been examined for its ability to decrease the amount of reactive oxygen species which appeared when liver microsomes (isolated from rats pretreated with phenobarbital) are incubated in the presence of Nitrofurantoin (NF). This molecule was used as a model compound in order to stimulate the production of superoxide anion and hydrogen peroxide, as well as to enhance the oxidation of NADPH and the oxygen uptake. These two later parameters were not modified when adding AD-5 to microsomes incubated in the presence of NF. However, in such conditions the amount of both and hydrogen peroxide was decreased. These effects were dose-dependent. These data suggest that AD 5 inhibits the building up of superoxide and consequently the production of hydrogen peroxide. We postulate that AD-5 acting as an oxygen derived free radical scavenger, can be used to inhibit the oxidative injury induced by nitrofurantoin and other redox cycling drugs

Increase in the survival time of mice exposed to ionizing radiation by a new class of free radical scavengers.

N-acyl dehydroalanines react with and scavenge mainly superoxide radical (O-2.) and hydroxyl radical (HO.). The ortho-methoxyphenylacetyl dehydroalanine derivative, indexed as AD-20, protects mice against damage resulting from total body X-irradiation, as measured by the increase in their survival time. AD-20 increases the LD50 at 30 days from 6.1 to 7.3 Gy in animals exposed to a wide range of X-rays (6 to 10 Gy). The dose reduction factor (D R F) of AD-20 is 1.20. We postulate that such radioprotective effect may result from its free radical scavenging activity

Inhibition of protein synthesis induced by adenine nucleotides requires their metabolism into adenosine.

Adenine nucleotides and adenosine inhibit the incorporation of radiolabelled leucine into proteins of isolated hepatocytes. Impairment occurred with nucleotides which can be converted into 9-beta-D-ribofuranosyladenine (adenosine) but was not observed after treatment with adenine or AMPCPP (the alpha, beta-methylene analogue of ATP). Metabolism into adenosine was further suggested by the increase in cellular ATP levels following treatment of hepatocytes with ATP, adenosine or AMPPCP (the beta, gamma-methylene ATP analogue) while AMPCPP was without any significant effect. The inhibition of protein synthesis caused by adenosine was not due to a lytic effect nor to a general disturbance in hepatic functions and was reversed when the cells were washed and transferred to a nucleoside-free medium. This impairment, however, was not coupled to the activation of adenylate cyclase, as preincubation of hepatocytes with P1 purinoceptor antagonists failed to prevent protein synthesis inhibition. In contrast, L-homocysteine enhanced the inhibitory effect of adenosine on the incorporation of radiolabelled leucine into proteins. Our results thus suggest that the inhibition of protein synthesis caused by adenine nucleotides requires their conversion into adenosine. They also indicate that the inhibitory effect of adenosine does not involve a receptor-mediated effect but may be related to an increase in S-adenosylhomocysteine content and a subsequent low level of macromolecule methylation

Inhibition of O-2-.-mediated and Ho.-mediated Processes By a New Class of Free-radical Scavengers - the N-acyl Dehydroalanines

N-phenylacetyl dehydroalanines are captodative olefins. They inhibit two processes mediated by superoxide anion (O2-.) in a concentration dependent manner: reduction of NBT to blue formazan and oxidation of epinephrine to adrenochrome. They also inhibit in a dose related way the degradation of deoxyribose produced during either the Fenton reaction or the radiolysis of water, which are the two experimental sources of hydroxyl radical (HO.) production. Based on the results obtained with superoxide dismutase, mannitol, thiourea, and uric acid, we postulate that these competitive inhibitory effects suggest a reaction between the dehydroalanine derivatives and the two oxygen derived radicals. Hydroxyl free radical is scavenged more efficiently than superoxide anion. Substitution of the phenyl ring by methoxy groups does not modify significantly the activity. These molecules possess three target active sites which can react with free radicals