Oxidative Stress in Caffeine Action on the Proliferation and Death of Human Breast Cancer Cells MCF-7 and MDA-MB-231.

To investigate the effects of caffeine on the proliferation and death of human breast cancer cells MCF-7 and MDA-MB-231. Cells were exposed to 1, 2.5, 5 and 10 mM of caffeine during 24 h, and oxidative stress (OS), cell proliferation and death, metabolic activity and DNA lesions were evaluated in the collected samples.

Pulmonary Emphysema Impairs Male Reproductive Physiology Due To Testosterone and Oxidative Stress Imbalance in Mesocricetus auratus.

This study evaluated whether pulmonary emphysema affects sperm quality, male reproductive organs, and testosterone levels in adult male hamsters. Mesocricetus auratus males (130-150 g) were subdivided into a control group (C group) and an emphysema group (E group). The C group received an intratracheal instillation of saline solution (0.

Metformin prevention of doxorubicin resistance in MCF-7 and MDA-MB-231 involves oxidative stress generation and modulation of cell adaptation genes.

Metformin was shown to sensitize multidrug resistant breast cancer cells; however, the mechanisms involved in this capacity need to be clarified. We investigated oxidative stress and inflammatory-related pathways during the induction of doxorubicin resistance in MCF-7 and MDA-MB-231 human breast cancer cells (DOX-res group), and evaluated metformin-induced cellular responses that resulted in the prevention of doxorubicin resistance (Met-DOX group). Microarray analysis demonstrated that DOX-res changed the expression of genes involved in oxidative stress (OS) and the TGF- β1 pathway.

Does l-glutamine-supplemented diet extenuate NO-mediated damage on myenteric plexus of Walker 256 tumor-bearing rats?

This study was designed to appraise the relationship between enteric neuropathy and oxidative stress in cancer cachexia under l-glutamine-supplemented diet. Total and nitrergic neuronal populations were investigated in jejunum and ileum in four experimental groups: control (C); control l-glutamine-supplemented diet (CG); Walker-256 tumor (TW); and Walker-256 tumor supplemented with l-glutamine (TWG). In addition, local oxidative stress, neuronal nitric oxide synthase (nNOS) enzyme and nitric oxide (NO) levels were evaluated.

Mechanism of metformin action in MCF-7 and MDA-MB-231 human breast cancer cells involves oxidative stress generation, DNA damage, and transforming growth factor β1 induction.

The participation of oxidative stress in the mechanism of metformin action in breast cancer remains unclear. We investigated the effects of clinical (6 and 30 μM) and experimental concentrations of metformin (1000 and 5000 μM) in MCF-7 and in MDA-MB-231 cells, verifying cytotoxicity, oxidative stress, DNA damage, and intracellular pathways related to cell growth and survival after 24 h of drug exposure. Clinical concentrations of metformin decreased metabolic activity of MCF-7 cells in the MTT assay, which showed increased oxidative stress and DNA damage, although cell death and impairment in the proliferative capacity were observed only at higher concentrations.