In vitro and in vivo activities of guajiru fruit (Chrysobalanus icaco L.) in oxidative stress, DNA damage, and inflammation biomarkers

Author(s)

Vinicius de Paula Venancio

• Document type: Doctoral Thesis
• Press: Ribeirão Preto.
• Institution: Universidade de São Paulo (USP). Faculdade de Ciências Farmacêuticas de Ribeirão Preto (PCARP/BC)
• Defense date: 2016-09-13

Examining board members

Lusania Maria Greggi Antunes; Luciana Azevedo; Elza Tiemi Sakamoto Hojo; Susanne Ursula Talcott

• Advisor: Lusania Maria Greggi Antunes

Abstract

Guajiru (Chrysobalanus icaco L.) is a fruit rich in anthocyanins, which exert several beneficial effects on health. Although guajiru leaves are used in folk medicine as hypoglycemic and antioxidant, the fruit effects on health remain unknown. The aim of this study was to evaluate the effects of guajiru fruit against in vivo DNA damage and oxidative stress and in vivo/in vitro inflammation. Male Wistar rats (4-5 weeks old, 110 g) were divided into eight groups and treated for 14 days with water or lyophilized guajiru fruit (100, 200 or 400 mg/kg b.w.) by gavage. On the 14th day, animals received physiologic solution or DXR (15 mg/kg b.w. i.p.) and were euthanized after 24 hours. Genotoxicity and antigenotoxicity were evaluated by comet assay in peripheral blood, liver, kidney, and heart. Mutagenicity and antimutagenicity of guajiru fruit were investigated by micronucleus test in peripheral blood and bone marrow. The oxidative burst was measured in peripheral blood neutrophils. Oxidative stress parameters involved the concentration of thiobarbituric acid reactive substances, reduced/oxidized glutathione ratio, and catalase activity in liver, kidney and heart. The expressions of DNA damage/repair genes Gadd45a (growth arrest and DNA damage-inducible alpha), Parp1 (Poly(ADP-ribose) polymerase 1), and Xrcc2 (X-Ray Repair complementing defective repair in Chinese hamster cells 2) and pro-inflammatory markers Il-1 ? (interleukin 1 beta), Il-6 (interleukin 6), Nf-kb (nuclear factor kappa B), and Tnf-? (tumor necrosis factor alpha) were evaluated by real-time quantitative PCR. Human colon cell lines CCD- 18Co (fibroblasts), and HT-29 (adenocarcinoma) were treated with guajiru anthocyanins (1.0 - 20.0 mg/L gallic acid equivalents - GAE) and the expressions of IL-1 ?, IL-6, NF-kB and TNF-? were analyzed at mRNA and protein levels. TNF-? was used to induce inflammation in CCD-18Co cells. Guajiru fruit phytochemicals were quantified and characterized by chromatographic and spectrometric methods. The concentrations of 19 chemical elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). Delphinidin, cyanidin, petunidin and peonidin were the major anthocyanins in this fruit. Significant amounts of phytochemicals, magnesium, and selenium were found in this fruit. Guajiru fruit displayed in vivo antioxidant activity in neutrophils, antigenotoxicity in peripheral blood and antimutagenicity in bone marrow and peripheral blood. Guajiru fruit decreased DNA damage in liver, kidney, and heart. This fruit decreased the expression of Gadd45a, Il-1 ?, and Tnf-?, in tissues. Cell proliferation was suppressed in HT-29 cells, and this was accompanied by increased intracellular ROS production as well as decreased TNF-?, IL-1 ?, IL-6, and NF-kB expressions. There was no cytotoxic effect of guajiru fruit anthocyanins in CCD-18Co cells. IL-1 ?, IL-6, and TNF-? protein expressions were reduced in TNF-?-treated CCD-18Co cells by guajiru fruit anthocyanins. The findings from this investigation demonstrated that phytochemicals and chemical elements in guajiru fruit possess antigenotoxic, antimutagenic, antioxidant and antiinflammatory effects and encourage other in vivo and clinical studies with this underutilized fruit. (AU)

• FAPESP's process: 11/21471-6 - In vitro and in vivo activities of guajiru fruit (Chrysobalanus icaco L.) in oxidative stress, DNA damage and inflammation biomarkers
• Grantee: Vinicius de Paula Venancio
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)