Title:Guavira Fruit Pomace Promotes Immunomodulation and Reduction of
Tumor Growth in Walker 256 Tumor-Bearing Rats
Volume: 20
Issue: 9
Author(s): Natália Eirão Zulin, Carolina Garcia Martins, Márcia Helena Appel, Débora Salles da Silva Coutinho, Amanda Plaça Bialli, Daiana Milena Bronoski, Stephanie Rubianne Silva Carvalhal, Elisvania Freitas dos Santos, Paulo Sérgio Loubet Filho, Sandro José Ribeiro Bonatto, Luiz Cláudio Fernandes, Lucimara Mach Côrtes Cordeiro and Fabíola Iagher*
Affiliation:
- Department of Physiology, Division of Biological Sciences, Federal University of Parana, Curitiba, PR, Brazil
Keywords:
Campomanesia sp., guavira, fruit pulp industry, Walker tumor, immune response, polysaccharides.
Abstract:
Background: Guavira fruit is widely used for juice extraction purposes, and this process
generates large amounts of pomace (waste). Guavira pomace was dried and milled to produce
guavira pomace flour (GPF), which is rich in antioxidants and dietary fibers (polysaccharides). These
compounds are known for their immunomodulatory and antitumor effects.
Objective: To investigate whether GPF intake promotes immunomodulation and reduces Walker
256 tumor growth in rats.
Methods: GPF was provided to Wistar rats in two different models: 1) 15-day Model, according to
which, Walker 256 tumor-bearing rats received GPF (63 mg/200 g b.w./day) simultaneously to tumor
growth for 15 days; 2) 45-day Model, according to which, tumor-bearing rats received GPF
for 30 days before tumor cell implantation, as well as during tumor growth - it totaled 45 days. After
animals were euthanized, tumors were collected and weighed, and tumor cells were isolated for
proliferation capacity determination ex vivo. Enzymatic/colorimetric methods were used to determine
resident peritoneal macrophages’ functionality, whereas blood T and B lymphocytes were assayed
for proliferation capacity, ex vivo, under stimuli.
Results: The 15-day Model did not show tumor mass or cell proliferation reduction in the treated
group. GPF stimulated macrophage response in tumor-bearing and non-tumor-bearing rats. However,
there was a substantial reduction in tumor mass and tumor cell proliferation under the 45-day
Model. Macrophage and lymphocyte response decreased; it suggested that GPF can directly act in
the tumor.
Conclusion: Based on these findings, GPF has immunomodulatory and antitumor actions, and ingestion
time plays a key role in them.