The Venom of Philippine Tarantula (Theraphosidae) Contains Peptides with Pro-Oxidative and Nitrosative-Dependent Cytotoxic Activities against Breast Cancer Cells (MCF-7) In Vitro

Background: Breast cancer is a multifactorial disease that affects women worldwide. Its progression is likely to be executed by oxidative stress wherein elevated levels of reactive oxygen and nitrogen species drive several breast cancer pathologies. Spider venom contains various pharmacological peptides which exhibit selective activity to abnormal expression of ion channels on cancer cell surface which can confer potent anti-cancer activities against this disease. Methods: Venom was extracted from a Philippine tarantula by electrostimulation and fractionated by reverse phase-high performance liquid chromatography (RP-HPLC). Venom fractions were collected and used for in vitro analyses such as cellular toxicity, morphological assessment, and oxidative stress levels. Results: The fractionation of crude spider venom generated several peaks which were predominantly detected spectrophotometrically and colorimetrically as peptides. Treatment of MCF-7 cell line of selected spider venom peptides induced production of several endogenous radicals such as hydroxyl radicals (•OH), nitric oxide radicals (•NO), superoxide anion radicals (•O2−) and lipid peroxides via malondialdehyde (MDA) reaction, which is comparable with the scavenging effects afforded by 400 µg/mL vitamin E and L-cysteine (p<0.05). Concomitantly, the free radicals produced decrease the mitochondrial membrane potential and metabolic activity as detected by rhodamine 123 and tetrazolium dye respectively (p>0.05). This is manifested by cytotoxicity in MCF-7 cells as seen by increase in membrane blebbing, cellular detachment, caspase activity and nuclear fragmentation. Conclusion: These data suggest that the Philippine tarantula venom contains peptide constituents exhibiting pro-oxidative and nitrosative-dependent cytotoxic activities against MCF-7 cells and can indicate mechanistic insights to further explore its potential application as prooxidants in cancer therapy.     

Pädiatrie aktuell – Forschung kurz notiert

Monatsschrift Kinderheilkunde -     

School readiness among low-income black children: family characteristics,parenting, and social support

This study focuses on the associations between family variables and academic and social school readiness in low-income Black children. Analyses drew from the National Institute for Child Development (NICHD) Study of Early Child Care and Youth Development dataset. The participants included 122 children and their mothers. Data collection occurred when the children were 1, 6, 15, 24, 36, and 54 months old. Findings indicated that maternal sensitivity and the quality of the home environment predicted cognitive and language outcomes, whereas maternal depression and social support predicted social–behavioural outcomes. In addition, the impact of family resources on cognitive and language outcomes was fully mediated by parenting behaviours and the impact of social support on behaviour problems was fully mediated through maternal depression. Implications for family intervention are discussed.