Induction of Apoptosis and Decrease of Autophagy in Colon Cancer Cells by an Extract of Lyophilized Mango Pulp

Previous studies have indicated that mango fruit has a chemopreventive capacity against colorectal cancer cells. The objective of this research was to evaluate the effect of an aqueous extract of lyophilized mango pulp (LMPE) on colon adenocarcinoma cells (SW480) and their metastatic derivatives (SW620) death and cellular invasion. DNA fragmentation was assessed by TUNEL assay; autophagy and expression of DR4 and Bcl-2 by flow cytometry; the expression of 35 apoptosis-related proteins and of matrix metalloproteinases 7 and 9 by immunodetection; and the invasive capacity of the cells by Boyden chamber. The results showed that LMPE at 30 mg/mL and 48 h of exposure results in DNA fragmentation and apoptosis in SW480 (p < 0.001) and SW620 (p < 0.01) cells. Additionally, LMPE decreased autophagy in the SW480 and SW620 cell lines (p < 0.001), which could sensitize them to the DNA damage generated by LMPE. The LMPE did not modulate the expression of matrix metalloproteinases 7 and 9, nor did it affect cellular invasion processes in the SW480 and SW620 cell lines. In conclusion, LMPE induces apoptosis and decreases autophagy in SW480 and SW620 cells.

Inhibition of Cell Proliferation and Induction of Cell Cycle Arrest in Colon Cancer Cells by Lyophilized Mango (Mangifera indica L.) Pulp Extract

The present study evaluated the antiproliferative capacity and possible cell death mechanisms of lyophilized mango pulp extract (LMPE), applied to human colon cancer cells (SW480) and their metastasis-derived counterparts (SW620). The total phenolic content of LMPE was estimated by the Folin-Ciocalteu method. Three assays were employed to determine its antioxidant capacity: ferric-reducing antioxidant power, oxygen radical absorbance capacity, and 2,2-diphenyl-1-picrylhydrazyl. Furthermore, the antiproliferative activity of LMPE was assessed by sulforhodamine B, clonogenic, and Ki-67 assays. Flow cytometry was employed to examine the cell cycle, production of intracellular reactive oxygen species (ROS), cell-surface phosphatidylserine, and change in mitochondrial membrane potential. LMPE exhibited a high level of total phenolic content and antioxidant activity. The mean maximal inhibitory concentration values of LMPE at 48 h of exposure were 43 and 29 mg/mL for SW480 and SW620, respectively. In the SW480 and SW620 cell lines, LMPE at 50 mg/mL and 48 h of exposure induced an increase in intracellular ROS, cell cycle arrest in the G2/M phase, and probably, apoptotic processes without mitochondrial depolarization. LMPE had an antiproliferative capacity against the human colorectal cancer cell lines SW480 and SW620. These results highlight the chemopreventive potential of LMPE in colorectal cancer treatments.

Impact of in vitro gastrointestinal digestion on the bioaccessibility and antioxidant capacity of bioactive compounds from Passion fruit (Passiflora edulis) leaves and juice extracts

The fruits consumption is highly associated with a lessening in the risk of the chronic noncommunicable diseases. Despite their content of bioactive compounds, physiological conditions might affect their bioaccessibility and biological potential. Hence, the purpose of this research was to evaluate the bioaccessibility and in vitro antioxidant capacity of bioactive compounds (polyphenols, ascorbic acid, and mono/oligosaccharides) from passion fruit (Passiflora edulis) juice and leaves extracts (PJE and PLE, respectively) during an in vitro gastrointestinal digestion. PLE exhibited the highest overall bioaccessibility of phenolics and mono/oligosaccharides. Ascorbic acid and kaempferol were the most bioaccessible (up to 12- and 13-fold, respectively) compounds and showed the highest net permeabilities (0.32-34.65 × 10^-5 ). Chlorogenic acid, quercetin, and xylose showed the highest correlation with the antioxidant capacity (ABTS/DPPH methods). These results indicated the ability of digestion to improve bioaccessibility and antioxidant capacity of bioactives compounds from P. edulis extracts. PRACTICAL APPLICATIONS: Several international organizations, World Health Organization (WHO) among them, are actively encouraging an increase in the fruit and vegetable intake worldwide in response to the global rise in noncommunicable diseases, among other actions. Fruits and processed foods are increasingly used in the European food industry. Additionally, exotic and tropical fruits cannot be produced in the European Union, which opens up a variety of opportunities for our Colombian tropical fruits such as mango or exotic fruits such as passion fruit. Evaluating parameters such as bioaccessibility and intestinal permeability of these bioactives derived from both P. edulis juice and leaves extracts contributes with new evidence regarding their stability along the gastrointestinal tract and their consumption as a source of health-promoting compounds. The results of this research are an important achievement on the way to make the transition from basic to applied research. Informing the health benefits of this tropical fruit can stimulate its demand.

Differential activation of Fas (CD95) mediated apoptosis by apple procyanidins in human colon cancer cells SW480 and their derived metastatic cells SW620

Introduction: We investigated the effects of apple procyanidins (Pcy), oligomers of catechins and epicatechins on Fas receptor expression and function in human colon adenocarcinoma cells (SW480) and in their derived metastatic cells (SW620). Methods: Pcy were characterized by reverse-phase HPLC. Cell death, Fas proteins, DNA fragmentation, and mitochondrial membrane potential were analyzed by flow cytometry. Fas mRNA was analyzed by RT-PCR in real time. Results: Pcy up-regulated the expression of the Fas receptor at the cell surface of both cell lines but activated Fas gene transcription only in SW620 cells. In SW480 cells, Pcy combined with Fas agonist CH-11 enhanced Fas-mediated apoptosis involving the loss of mitochondrial membrane potential and DNA fragmentation, which were abrogated by the antagonist antibody of Fas receptor, the anti-Fas ZB4. On the contrary, in SW620 cells, CH-11 was not able to enhance Pcy-triggered apoptosis indicating that Fas receptor-mediated apoptosis was not activated in these cells despite an up-regulation of Fas receptor gene expression. However, it was observed in SW620 cells that Pcy activated the Fas receptor-mediated apoptotic pathway after a specific blockage of TRAIL-death DR4/DR5 receptors. Conclusions: The present data showed that Pcy were able to activate the Fas receptor apoptotic pathway in SW480 cells and favored a cross-talk between TRAIL and Fas receptors in SW620 cells because specific blocking of TRAIL death receptors favored activation of the Fas receptor-mediated apoptosis. These important data may allow the emergence of new therapeutic protocols targeting death receptors against resistant metastatic cells.