Identification of a novel series of N-phenyl-5-[(2-phenylbenzimidazol-1-yl)methyl]-1,3,4-oxadiazol-2-amines as potent antioxidants and radical scavengers.

In this study, some novel 5-[[2-(phenyl/p-chlorophenyl)-benzimidazol-1-yl]-methyl]-N-substituted phenyl-1,3,4-oxadiazol-2-amine derivatives (28-45) with an oxadiazole ring were synthesized. The antioxidant properties and radical scavenging activities of the compounds were investigated employing various in vitro systems: hepatic microsomal NADPH-dependent inhibition of lipid peroxidation levels, scavenging of DPPH free radicals, and inhibition of microsomal ethoxyresorufin O-deethylase activity (EROD). Compounds 34 and 41 were found to be good scavengers of DPPH radicals (76% and 84%) when compared to BHT (90%). Almost all of the compounds examined were found to possess a good inhibitor effect on the microsomal EROD activity. Moreover, 32 and 41 were more active analogs (97% and 98%) on the microsomal EROD activity than caffeine (85%).

Synthesis and antioxidant properties of substituted 2-phenyl-1H-indoles.

In this study, we report the design, synthesis and antioxidant activity of a series of substituted 2-(4-aminophenyl)-1H-indoles and 2-(methoxyphenyl)-1H-indoles. The new compounds are structurally related to the known indole-based antioxidant lead compound melatonin (MLT), and the antitumour 2-(4-aminophenyl)benzothiazole and 2-(3,4-dimethoxyphenyl)benzothiazole series. Efficient access to the target 2-phenylindoles was achieved via Fischer indole synthesis between substituted phenylhydrazines and acetophenones. 2-(4-Aminophenyl)indoles (such as the 6-fluoro analogue 3b) in particular showed potent antioxidant activity in the DPPH and superoxide radical scavenging assays (80% and 81% inhibition at 1mM concentration of 3b, respectively), at a level comparable with the reference standard MLT (98% and 75% at 1 mM).

Neurological Complications and Potential Effects of Covid-19: Symptoms and Conceivable Mechanisms.

A novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in December 2019 in Wuhan, China. The new coronavirus disease (COVID-19) was declared a global pandemic by the World Health Organization (WHO) in March 2020. SARS-CoV-2 can invade the nervous system aside from infecting the respiratory system as its primary target. The most common nervous system symptoms of COVID-19 are stated as headache, myalgia, fatigue, nausea, vomiting, sudden and unexplained anosmia, and ageusia. More severe conditions such as encephalomyelitis, acute myelitis, thromboembolic events, ischemic stroke, intracerebral hemorrhage, Guillain-Barré-syndrome, Bell's palsy, rhabdomyolysis, and even coma have also been reported. Cohort studies revealed that neurological findings are associated with higher morbidity and mortality. The neurological symptoms and manifestations caused by SARS-CoV-2 and COVID-19 are examined and summarized in this article.

Trachystemon orientalis (L.) G. Don as a Valuable Source of Rosmarinic Acid: Biological Activities and HPLC Profiles.

Objectives: Trachystemon orientalis (L.) G. Don, colloquially known in Türkiye as "kaldirik", is an edible plant belonging to the Boraginaceae. This plant has been practiced in traditional medicine for many years for its various therapeutic benefits. The effectiveness and chemical composition of plants can vary depending on their parts, age, and extraction solvent. Therefore, the current study aimed to define the biological activities of various parts and extracts of T. orientalis, which were collected in distinct seasons as young and mature, and investigate the main component responsible for these biological effects. Material and Methods: Plant material was collected in different seasons from the northwest of Türkiye. 2,2'-Azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activities were investigated to assess antiradical and antioxidant potential of the extracts. Anti-inflammatory activity of the extracts was also tested using human red blood cell membrane stabilizing method. Folin-Ciocalteu test was conducted to determine the total phenolic content. Reverse phase-high performance liquid chromatography-photodiode array detector (RP-HPLC-PDA) analysis was performed. Results: Both methanol and aqueous extracts exhibited significant radical scavenging and anti-inflammatory activities compared with control (p<0.05). The highest percentage of inhibition on ABTS and DPPH free radicals was obtained in aqueous extracts of the mature herbs and roots, respectively. Methanol extracts of the mature roots and herbs exhibited the strongest anti-inflammatory capacity. Rosmarinic acid possessed a much higher antioxidant and anti-inflammatory effect than the reference compounds used in each assay in our study. High rosmarinic acid content of the extracts suggests that the compound responsible for the great biological activity potential is rosmarinic acid. Conclusion: To the best of our knowledge, the presence of rosmarinic acid in herbs and roots of T. orientalis was shown for the first time in our present study. Phytochemical composition and effective biological activities of T. orientalis explain its traditional use and indicate its significant potential in pharmaceutical industry applications.

Synthesis and antioxidant activity evaluations of melatonin-based analogue indole-hydrazide/hydrazone derivatives.

Melatonin (MLT) is a hormone synthesized from the pineal gland. It is a direct scavenger of free radicals, which is related to its capability to defend cells from oxidative stress. Recently MLT-related compounds are under investigation to establish which exhibit the maximum activity with the lowest side effects. In this study 5-chloroindole hydrazide/hydrazone derivatives were synthesized from 5-chloroindole-3-carboxaldehyde and phenyl hydrazine derivatives. All the compounds characterized and in vitro antioxidant activity was investigated against MLT and BHT. Most of the compounds showed strong inhibitory effect on the superoxide radical scavenging assay at 1 mM concentration (79 to 95%). Almost all the tested compounds possessed strong scavenging activity against the DPPH radical scavenging activity with IC(50) values (2 to 60 µM). Lastly, compound 1j revealed stronger inhibitory activity against MLT in the LP inhibitory assay at 0.1mM concentration (51%) while the rest of the compounds showed moderate inhibition.

Design and one-pot and microwave-assisted synthesis of 2-amino/5-aryl-1,3,4-oxadiazoles bearing a benzimidazole moiety as antioxidants.

In this study, two new series of 2-amino-1,3,4-oxadiazoles and 5-aryl-1,3,4-oxadiazoles carrying a benzimidazole moiety were synthesized. The antioxidant properties of these compounds were investigated in vitro by the determination of the microsomal NADPH-dependent inhibition of lipid peroxidation levels (LP), the microsomal ethoxyresorufin O-deethylase activity (EROD), and DPPH radical scavenger effects. Among the tested compounds, 2-[(2-(4-chlorophenyl)-1H-benzo[d]imidazole-1-yl)methyl]-5-(4-fluorophenyl)-1,3,4-oxadiazole (9) was found to be the most active compound in all three in vitro systems.

Evaluation of novel aminomethyl indole derivatives as Src kinase inhibitors and antioxidant agents.

BACKGROUND: Oxidative stress has been implicated in aging and in a variety of diseases affecting the nervous, respiratory, cardiovascular and gastrointestinal system in humans. Reactive oxygen species (ROS) have been associated with mechanisms to activate kinases, such as protein tyrosine kinases, which may initiate malignant transformation. Significant evidences of the activation of protein kinases by oxidative stress brought increased attention to the role of antioxidants in these mechanisms. Therefore, recent efforts have focused on revealing the relationship between protein kinase inhibition and the levels of ROS production. METHODS: Antioxidant properties of aminomethyl indole derivatives were investigated by employing various in vitro systems, microsomal NADPH-dependent inhibition of lipid peroxidation (LP), interaction of 2,2-diphenyl-1-picrylhydrazyl and scavenging of superoxide anion radical by virtue of superoxide dismutase inhibitory activity. In vitro tyrosine kinase assays of the aminomethyl indole derivatives were evaluated by changes in the enzymatic activity of pp60(c-Src) tyrosine kinase through alterations in the phosphorylation level of immobilized kinase substrate. RESULTS: Analysis of the antioxidant effects of indole 1a-c, bromo indole 2a-c and phenyl indole 3a-c derivatives revealed almost equal inhibition against LP for 5-bromo indole 2a-c and phenyl indole 3a-c derivatives and slight inhibition against superoxide dismutase only for 1a and 1c. Nonsubstituted compounds at position 5 showed half-inhibition of LP. Compound 1a has tyrosine kinase inhibition with an IC(50) of 102.6 ± 1.16 µM. CONCLUSION: The substitution feature at position 5 of the indole ring certainly plays an important role in both tyrosine kinase inhibition and antioxidant capacity. While certain lipophilicity of this substitution is important for antioxidant activity, it may, on the other hand, have a negative impact on the inhibition of Src kinase.

Chemoresistance in Malignant Intracranial Tumors: Longer Survival with Negative MDR1 Expression.

AIM: To analyze the Glutathione S-transferase (GST)-P, GST-M, cytochrome p450 (CYP)1-A1, CYP1-B1, and multidrug resistance (MDR)-1 expressions in malignant intracranial tumor (ICT)s, and to elicit their role on patient survival. MATERIAL AND METHODS: GST-P, GST-M, CYP1-A1, CYP1-B1, and MDR-1 expressions were analyzed using immunostaining in 149 samples from 141 patients with preoperative ICT diagnosis. The case characteristics were reviewed, and the enzyme expressions were equated based on the age, gender, and tumor type. Then, 77 of 141 patients with malignant ICT and complete medical records postoperative were also investigated in detail for the relationship between the diagnosis, enzyme expression, and overall survival. RESULTS: The average age was 49.44 years, with 83 (58.45%) male patients. Among the 77 malignant ICTs, 38 (49.3%) and 29 were glial tumors and metastases, respectively, with a 13.35-month overall survival. Patients with metastatic tumor have approximately threefold higher GSTP level than those with glial tumors. MDR-1 expression was approximately twofold higher in > 60-year-old patients. No statistically significant association was found between patients? smoking behaviors, alcohol consumption, and overall survival. Only MDR-1 expression was correlated with overall survival. Better overall survival was observed in patients with a negative MDR-1 expression than those with a positive one. CONCLUSION: MDR-1 is an important indicator of survival in malignant intracranial tumor patients. Longer survival is associated with negative MDR-1 expression.

Antioxidant and antifungal properties of benzimidazole derivatives.

Antioxidant and radical scavenging properties of a series of 2-[4-(substituted piperazin-/piperidin-1-ylcarbonyl)phenyl]-1H-benzimidazole derivatives were examined. Free radical scavenging properties of compounds 11-30 and 33 were evaluated for the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide anion radical. In addition the inhibitory effects on the NADPH-dependent lipid peroxidation levels were determined by measuring the formation of 2-thiobarbituric acid reactive substances (TBARS) using rat liver microsomes. Compound 33 which has a p-fluorobenzyl substitutent at position 1 exhibited the strongest inhibition (83%) of lipid peroxidation at a concentration of 10(-3) M, while the nonsubstituted analogue 13 caused 57% inhibition. This result is fairly consistent with the antimicrobial activity results against both Staphylococcus aureus and Candida albicans.

N-substituted indole-3-imine derivatives and their amine congeners: antioxidant and Src kinase inhibitory effects.

Current evidences demonstrated that the activity of protein kinases can be controlled through oxidative stress induced by reactive oxygen species (ROS) and normalized by antioxidants. Recent studies with ROS, generated by mitochondria, suggested the potential signalling role of these species, where ROS, especially hydrogen peroxide, were proposed as membrane-related signalling components. The protein regulation by cellular redox states has shown that protein tyrosine kinase members, such as Src kinase and some of the members of the Src family kinases (SFKs), are proteins regulated by the cellular oxidation and reduction status. In this context, the oxidant or antioxidant potential of the synthetic Src kinase inhibitors previously synthesized and studied by our research group, such as N-substituted indole-3-imine and -amine derivatives, were investigated employing various acellular in vitro methods including microsomal NADPH-dependent inhibition of lipid peroxidation (LP), interaction of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and scavenging of superoxide anion radicals. Here, we report that some of the synthetic inhibitors designed for Src kinase target have both antioxidant and kinase inhibition properties.

Evaluation of the Antioxidant Potency of Seseli L. Species (Apiaceae).

OBJECTIVES: In the present study, the antioxidant potency of ethyl acetate (AcOEt) and methanol (MeOH) extracts from the aerial parts of Seseli L. species was investigated for the first time. MATERIALS AND METHODS: Seseli species L. such as Seseli andronakii Woronow ex Schischk., S. campestre Besser, S. corymbosum Boiss. & Heldr., S. gummiferum subsp. gummiferum Pall. ex Sm., S. hartvigii Parolly & Nordt, S. libanotis (L.) W.Koch, S. petraeum M.Bieb., S. peucedanoides (M.Bieb.) Koso-Pol., S. resinosum Freyn & Sint., and S. tortuosum L. growing in Turkey were collected and evaluated for their antioxidant capacity by using 1.1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and lipid peroxidation (LPO) inhibition methods. RESULTS: The highest activities as a scavenger of DPPH radicals were found in the AcOEt extracts of S. peucedanoides (M.Bieb.) Koso-Pol (IC50=0.49 mg/mL), and S. libanotis (IC50=0.75 mg/mL); α-tocopherol was used as a positive control. On the other hand, in the LPO assay, the highest activities were determined in AcOEt and MeOH extracts (at 5 mg/mL) of S. tortuosum and S. libanotis (84-94%). CONCLUSION: This report gives important information about the antioxidant capacity of Seseli L. species. This research on antioxidant capacity proves that the use of some species used in Eastern Anatolia (in salads) is correct. With this screening study performed in Seseli L. species growing in Turkey, in the future, it is planned to isolate antioxidant compounds from the most active strains of Seseli L.

Melatonin analogue new indole hydrazide/hydrazone derivatives with antioxidant behavior: synthesis and structure-activity relationships.

Melatonin (MLT) is a hormone produced in the brain by the pineal gland, from the amino acid tryptophan. It is also an antioxidant hormone with a particular role in the protection of nuclear and mitochondrial DNA. In recent years, many physiological properties of MLT have been described resulting in much attention in the development of synthetic compounds possessing the indole ring. Sixteen MLT analogue indole hydrazide/hydrazone derivatives were synthesized and in vitro antioxidant activity was investigated. Most of the compounds showed significantly higher activity than MLT at 10(-3) M and 10(-4) M concentrations.

Antimicrobial and Anti-Inflammatory Activity of Some Lathyrus L. (Fabaceae) Species Growing in Turkey.

OBJECTIVES: The present study aimed to evaluate the antimicrobial and anti-inflammatory activities of methanol extracts and n-hexane, ethyl acetate, chloroform, and water fractions of five Lathyrus species, namely Lathyrus armenus, Lathyrus aureus, Lathyrus cilicicus, Lathyrus laxiflorus subsp. laxiflorus, and Lathyrus pratensis, growing in Turkey. MATERIALS AND METHODS: The antimicrobial activities were screened against Staphylococcus aureus ATCC 29213, Bacillus subtilis ATCC 6633, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, and Candida albicans ATCC 10231. Broth dilution was used to determine the antimicrobial activities of extracts and fractions. In vitro anti-inflammatory activity of these extracts and fractions was determined using human red blood cell membrane stabilization. RESULTS: The results demonstrated that ethyl acetate fractions of the tested species exhibited higher antimicrobial activity than the other extracts. Among all of the tested extracts and fractions, the highest anti-inflammatory activity was detected in water fractions. Furthermore, water fractions of L. pratensis showed better anti-inflammatory activity than acetylsalicylic acid and diclofenac sodium, which were used as standard drugs in this assay. CONCLUSION: The results indicate the membrane stabilizing effect of the various extracts and fractions of the Lathyrus species and could constitute preliminary work for in vivo anti-inflammatory activity experiments.

Synthesis and antioxidant properties of novel N-methyl-1,3,4-thiadiazol-2-amine and 4-methyl-2H-1,2,4-triazole-3(4H)-thione derivatives of benzimidazole class.

Some novel 1-methyl-4-(2-(2-substitutedphenyl-1H-benzimidazol-1-yl)acetyl)thiosemicarbazides (16a-20a), 5-[(2-(substitutedphenyl)-1H-benzimidazol-1-yl)methyl]-N-methyl-1,3,4-thiadiazol-2-amines (17b-20b), and 5-[(2-(substitutedphenyl)-1H-benzimidazol-1-yl)methyl-4-methyl-2H-1,2,4-triazole-3(4H)-thiones (16c-20c) were synthesized and tested for antioxidant properties by using various in vitro systems. Compounds 16a-20a were found to be a good scavenger of DPPH radical (IC(50), 26 microM; IC(50), 30 microM; IC(50), 43 microM; IC(50), 55 microM; IC(50), 74 microM, respectively) when compared to BHT (IC(50), 54 microM). Noteworthy results could not be found on superoxide radical. Compound 19b, which is the most active derivative inhibited slightly lipid peroxidation (28%) at 10(-3)M concentration. Compound 17c inhibited the microsomal ethoxyresorufin O-deethylase (EROD) activity with an IC(50)=4.5 x 10(-4)M which is similarly better than the specific inhibitor caffeine IC(50)=5.2 x 10(-4)M.

Synthesis and evaluation of N-substituted indole-3-carboxamide derivatives as inhibitors of lipid peroxidation and superoxide anion formation.

The in vitro antioxidant effects of novel N-substituted indole-3-carboxamides (I3CDs) 1-10 on rat liver microsomal NADPH-dependent lipid peroxidation (LP) levels and their free radicals scavenging properties were determined by the inhibition of superoxide anion formation (SOD). Among the synthesized compounds, 4, 5, 8 and 9 significantly inhibited SOD with an inhibition range at 84-100% at 10(-3) M concentration. The presence of halo substituents both ortho- and para- positions of these compounds resulted 100% inhibition of SOD. Comparison the activity results of halogenated and non-halogenated derivatives suggested that the halogenated compounds are more active than the non-halogenated compounds. On the other hand, the introduction of a para fluoro benzyl in the 1-position of indole (compounds 7, 8) has more impact on the SOD inhibition when the benzamide ring was mono halogenated. However, none of other compounds had a significant inhibitory effects on the level of lipid peroxidation.

Bioactivities of Alchemilla mollis, Alchemilla persica and Their Active Constituents

Abstract The aim of this study was to determine antimicrobial activities of Alchemilla mollis, Alchemilla persica as well as ellagic acid and miquelianin against Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans by using microbroth dilution method and anti-inflammatory activity by using human red blood cell (HRBC) membrane stabilization method. Microbroth dilution method was used to determine the antimicrobial activities. Extracts possessed activity having MIC values of 2.5-5-10mg/ mL, compounds possessed activity having MIC values of 1.25-2.5-4-5mg/mL. A.mollis aerial parts displayed the highest anti-inflammatory activity (IC50=1.22±0.07mg/mL). Ellagic acid and miquelianin were also determined as anti-inflammatory agents with 0.57±0.01mg/mL and 1.23±0.02mg/mL IC50 values, respectively. Total phenolic content and tannin content of the A.mollis and A.persica were determined as 357.00±75.80mg, 282.50±28.70mg PGE/g plant material and 18.02%, 18.63% respectively according to the method described by European Pharmacopoeia. Ellagic acid, miquelianin and catechin were analyzed by HPLC. The highest catechin content was detected in A.persica roots (6.69±0.05g/100g plant material). A.mollis aerial parts contain higher miquelianin (0.39±0.02g/plant material) and ellagic acid (1.56±0.01g/ plant material) than A.persica.

In vitro inhibitory potential of avocado fruits, Persea americana (Lauraceae) against oxidation, inflammation and key enzymes linked to skin diseases / Inhibidor potencial in vitro de frutos de aguacate, Persea americana (Lauraceae) contra la oxidación, inflamación y enzimas clave vinculadas a enfermedades de la piel

Abstract Introduction: Avocado (Persea americana Mill.) is a member of Lauraceae with one-seeded berry fruit and cultivated in all tropical, subtropical regions in the world and in the Southern coast region of Turkey. Oxidative damage caused by UV can trigger inflammation, resulting in serious inflammatory skin diseases including eczema, seborrheic dermatitis, hyperpigmentation and ageing. Enzyme inhibitors involved in melanogenesis, such as tyrosinase, have been used recently for hyperpigmentation and skin diseases in cosmetic products. Objective: This study aimed to evaluate the antioxidant, anti-inflammatory, anti-tyrosinase activities and total polyphenolic contents of the different parts of P. americana fruit. Methods: The fruit was divided into exocarp, mesocarp, seed, and then methanol and n-hexane extracts were prepared. DPPH and ABTS free radical scavenging capacities and inhibitory potentials on lipid peroxidation were determined to investigate the antioxidant potentials of the extracts. Anti-inflammatory activities of the extracts were evaluated by measuring the stabilization level of the human red blood cell membrane. The tyrosinase inhibitory activities of the samples were determined using mushroom tyrosinase. Results: In general methanol extracts possessed remarkable higher DPPH free radical scavenging activities than n-hexane extracts. The highest activity was determined in methanol extracts of seed (4.17 ± 0.04 mg/mL) followed by exocarp (5.25 ± 0.05 mg/mL). Overall methanol extracts possessed higher ABTS free radical scavenging activities than n-hexane extracts. The greatest ABTS free radical scavenging activity was obtained in methanol extracts of seed (0.03 ± 0.01 mg/mL). In the anti-lipid peroxidation assay, the greatest activity was noticed in methanol extracts of seed (7.71 ± 0.36 µg/mL) followed by exocarp (12.12 ± 0.34 µg/mL), while all n-hexane extracts were inactive. Overall methanol extracts exhibited higher anti-inflammatory and antioxidant properties than n-hexane extracts. However, the maximum anti-tyrosinase activity was determined in n-hexane extracts of exocarp (0.40 ± 0.01 mg/mL) followed by seed (0.46 ± 0.01 mg/mL). Conclusions: These extracts are promising candidates for use as natural products-based antioxidant and anti-inflammatory properties in inflammation-related disease, and also anti-tyrosinase properties in dermatological applications.

Resumen Introducción: El aguacate (Persea americana Mill.) es un miembro de Lauraceae, es una baya de una semilla que se cultiva en todas las regiones tropicales y subtropicales del mundo y la región costera sur de Turquía. El daño oxidativo causado por los rayos ultravioleta puede desencadenar inflamación, lo que posteriormente da como resultado enfermedades inflamatorias graves de la piel como eccema, dermatitis seborreica, hiperpigmentación y envejecimiento. Los inhibidores de enzimas implicados en la melanogénesis, como la tirosinasa, se han utilizado recientemente para la hiperpigmentación y enfermedades de la piel en productos cosméticos. Objetivo: Evaluar las actividades antioxidantes, antiinflamatorias, antitirosinasas y los contenidos polifenólicos totales de las partes del fruto de P. americana. Métodos: El fruto se dividió en tres partes: exocarpio, mesocarpio y semilla, y se prepararon extractos de metanol y n-hexano. Se determinaron las capacidades de eliminación de radicales libres de DPPH y ABTS y los potenciales inhibidores sobre la peroxidación de lípidos para investigar los potenciales antioxidantes de los extractos. Las actividades antiinflamatorias de los extractos se evaluaron midiendo el nivel de estabilización de la membrana de los glóbulos rojos humanos. Las actividades inhibidoras de tirosinasa de las muestras se determinaron utilizando tirosinasa de hongos. Resultados: En general, los extractos de metanol poseían actividades de eliminación de radicales libres de DPPH notablemente más altas que los extractos de n-hexano. La actividad más alta se presentó en extractos metanólicos de semilla (4.17±0.04 mg/mL) seguido del exocarpio (5.25±0.05 mg/mL). En general, los extractos de metanol poseían una mayor actividad de eliminación de radicales libres ABTS que los extractos de n-hexano. La mayor actividad captadora de radicales libres de ABTS se obtuvo en extractos metanólicos de semilla (0.03±0.01 mg/mL). En el ensayo de anti-peroxidación lipídica, la mayor actividad se observó en los extractos metanólicos de semillas (7.71±0.36 µg/mL) seguidos del exocarpio (12.12±0.34 µg/mL), mientras que todos los extractos de n-hexano estaban inactivos. En general, los extractos de metanol exhibieron mayores propiedades anti-inflamatorias y antioxidantes que los extractos de n-hexano. Sin embargo, la actividad anti-tirosinasa máxima se determinó en extractos de exocarpio de n-hexano (0.40±0.01 mg/mL) seguido de semillas (0.46±0.01 mg/mL). Conclusiones: Estos extractos son candidatos prometedores como productos naturales debido a sus propiedades antioxidantes y antiinflamatorias para tratar enfermedades relacionadas con la inflamación, y también propiedades antitirosinasas en aplicaciones dermatológicas.

Free Radical Scavenging Activity of Linum arboreum.

The methanol and water extracts of Linum arboreum.. aerial parts were screened for free radical scavenging activity. The free radical scavenging activity was determined spectrophotometrically on the basis of inhibition of cytochrome c reduction and the ability to bleach the stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). The methanol extracts of Linum arboreum. were shown to have potent antioxidant activity.

Immunohistochemical demonstration of the expression of CYP2E1 in human breast tumour and non-tumour tissues.

Environmental chemicals are one of the risk factors in breast cancer genesis. Cytochrome P450 2E1 (CYP2E1), a member of multigene superfamily of enzymes, plays a major role in the activation of some of these chemicals such as tobacco-derived N-nitrosamines. Using immunohistochemistry, the cellular distribution and the level of expression of CYP2E1 was assessed in breast tumour and surrounding tumour free (control) breast tissue in 25 pairs of samples obtained from females with infiltrating ductal carcinoma. Cells staining with the CYP2E1 antibody showed only cytoplasmic positivity with varying intensities in 100% (25/25) of tumours and 96% (24/25) of normal breast tissues. Cytoplasmic staining was present in invasive ductal carcinoma cells but not in tumour stroma. CYP2E1 was detected in normal epithelial, myoepithelial and to a lesser degree in some of the non-epithelial cells (e.g. endothelial cells). No positive staining was detected in other non-epithelial cells such as fibroblasts in normal breast tissues. When CYP2E1 staining was assessed semiquantitatively the mean staining score values of CYP2E1 was found to be significantly higher in tumours compared to that of normal breast tissues. These results show that CYP2E1 protein is expressed in both tumour and normal breast tissue with an increased expression in breast tumours.

Expression of CYP3A4 in human breast tumour and non-tumour tissues.

Cytochrome P450 3A4 (CYP3A4), a member of multigene superfamily of enzymes, plays a major role in the activation of procarcinogens such as polycyclic hydrocarbon dihydrodiols, aflatoxins and heterocyclic amines as well as of several drugs including tamoxifen which is used in breast cancer therapy. Using immunohistochemistry, the cellular distribution and the level of expression of CYP3A4 was assessed in breast tumour and surrounding tumour free (control) breast tissue in 25 pairs of samples obtained from females with infiltrating ductal carcinoma. Cells staining with the CYP3A4 antibody showed only cytoplasmic positivity with varying intensities in 100% (25/25) of tumours and 68% (17/25) of normal breast tissues. Cytoplasmic staining was present in invasive ductal carcinoma cells but not in tumour stroma. CYP3A4 was detected in normal epithelium and myoepithelium. Only focal staining was noted in some of the non-epithelial cells (e.g. endothelial cells) in normal breast tissues. When CYP3A4 staining was assessed semiquantitatively the mean staining score values of CYP3A4 were found to be significantly higher in tumours compared to that of normal breast tissues. These results show that CYP3A4 protein is expressed in both tumour and normal breast tissue with an increased expression in tumours.