Breast cancer is the most prevalent cancer and one of the leading causes of death among women in the world. Plants and herbs may play an important role in complementary or alternative treatment. The aim of this study was to evaluate the antioxidant and anti-proliferative potential of Urtica dioica. The anti oxidant activity of an aqueous extract of Urtica dioica leaf was measured by MTT assay and the FRAP method while its anti-proliferative activity on the human breast cancer cell line (MCF-7) and fibroblasts isolated from foreskin tissue was evaluated using MTT assay. Mechanisms leading to apoptosis were also investigated at the molecular level by measuring the amount of anti and pro-apoptotic proteins and at the cellular level by studying DNA fragmentation and annexin V staining by flow cytometry. The aqueous extract of Urtica dioica showed antioxidant effects with a correlation coefficient of r 2 =0.997. Dose-dependent and anti-proliferative effects of the extract were observed only on MCF-7 cells after 72 hrs with an IC 50 value of 2 mg/ml. This anti proliferative activity was associated with an increase of apoptosis as demonstrated by DNA fragmentation, the appearance of apoptotic cells in flow cytometry analysis and an increase of the amount of calpain 1, calpastatin, caspase 3, caspase 9, Bax and Bcl-2, all proteins involved in the apoptotic pathway. This is the first time such in vitro antiproliferative effect of aqueous extract of Urtica dioica leaf has been described for a breast cancer cell line. Our findings warrant further research on Urtica dioica as a potential chemotherapeutic agent for breast cancer.

Seaweeds contains different types of polysaccharides with high abilities. The aim of this study was to determine the potential of fucoidan polysaccharides for wound-healing properties. Fucoidans of two species of Padina (P. tetrastromatica and P. boergesenii), collected from the Persian Gulf northern coastal area, were extracted and analyzed using high-performance anion-exchange chromatography. Purified fucoidans were used to prepare a 2% topical ointment. Under aseptic conditions, two identical paravertebral full-thickness skin wounds (either by burn or excision) were made in 40 anesthetized male rats allocated into 4 groups. Either fucoidan ointments or the vehicle (ointment base) were applied to rats' wounds twice daily for 14 days. In addition to the examination of wound area reduction (days 3, 7, 10, and 14) and histopathological assays (days 7 and 10), tissue specimens were taken to the laboratory. Fucoidans obtained from both seaweeds induced significant wound area reduction compared to the vehicle at some time points after treatment. Histopathological examinations showed improvement in some healing signs including angiogenesis, collagen fiber formation, and epidermis formation. In conclusion, both species of Padina have significant wound-healing effects and fucoidan polysaccharides are the active constituents for this healing property. However, fucoidan obtained from P. boergesenii showed superior effects in this regard.

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It has been well known that oxidative stress and increased intracellular reactive oxygen species (ROS) have a pivotal role in disrupting the insulin signaling pathways leading to cellular insulin resistance. In this study, we evaluated arbutin's effects on glucose uptake by GLUT4 and cytoprotective properties in the L6 skeletal muscle cell line. The effect of arbutin and tertiary butyl hydrogen peroxide (t-BHP) on glucose uptake in cultured L6 cells was investigated by flow cytometry. We also evaluated gene expression levels of GLUT1 and GLUT4 in the L6 cells by quantitative real-time polymerase chain reaction analysis. The results from the study demonstrated that the optimum ROS generation occurred 3 h after 100 µM t-BHP treatment and pretreatment with arbutin (500 and 1000 µM) significantly inhibited the t-BHP induced ROS generation (p < .05). Our result indicated that 3 h pretreatment of L6 cells with 1000 μM of arbutin before 50 μM t-BHP significantly increased glucose uptake than the 50 μM t-BHP alone group (p < .05). Our findings may suggest that an increase in the uptake of 2-NBDG by L6 cells with arbutin pretreatment can be associated with increased expression of GLUT4 and GLUT1 under oxidative stress.