Helen Drakou

Abstract

A high percentage of fat in the diet has been implicated through epidemiological studies in several human cancers. Studies in experimental animals have produced evidence that increasing the fat in the diet decreases the animal’s ability to restrict tumor development and growth. In previous work done in this laboratory with BALB/c mice injected with herpes simplex Type 2-transformed mouse cells (H238), the effects of a diet which greatly enhanced tumor growth was compared with one which restricted tumor growth. The latter, a low (5%) fat, low protein diet, in which the protein was casein, was also found to produce a higher cell mediated immunity than the former, a high (30%) fat, low protein diet in which the protein was wheat gluten. The present research was designed to determine to what extent the level of fat and to what extent the source of protein were factors in tumor development and to determine relationships of these with cell-mediated immunity. Secondly, the four diets used were all designed to be equal with respect to nutrient (protein, fiber, each individual vitamin, each individual mineral) to calorie ratios.

Four diets were used in the study: the two diets mentioned previously (Diet 1 and Diet 4 respectively), and two control diets. One of the latter was a high (30%) fat, low (11%) protein diet in which the protein was casein (Diet 3); the other was a low (5%) fat, low (11%) protein diet in which the protein was wheat gluten (Diet 2). The mice were fed for 10 weeks (Diets 1 and 3) or for 20 weeks (Diets 2 and 4) before injection of the tumor cells. Non-injected mice served as the controls.

Tumor volume measurements were made once or twice a week. At euthanization each mouse and its spleen were weighed and relative spleen weights were calculated. The spleen cells were used in a microculture lymphocyte transformation test (LTT) using phytohemagglutinin (PHA), concanavalin A (ConA) or lipopolysaccharide (LPS) as mitogens.

The type of protein present in the diets of the mice (casein or wheat gluten) appeared to be the most important factor influencing tumor development. Mice fed the 11% casein had the lowest tumor volumes and higher mean counts per minute values (when treated with PHA, ConA or LPS) as long as the level of fat was also low (5% corn oil). In contrast, mice fed the 11% protein-wheat gluten, 30% fat developed significantly greater tumor volumes throughout the study (compared to mice fed the 11% wheat gluten, 5% fat diet) and depressed lymphoproliferative responses to mitogenic stimulation.

LLU Discipline

Microbiology

Department

Microbiology

School

Graduate School

First Advisor

Robert L. Nutter

Second Advisor

William C. Eby

Third Advisor

Robert W. Teel

Degree Name

Master of Science (MS)

Degree Level

M.S.

Year Degree Awarded

1986

Date (Title Page)

9-1986

Language

English

Library of Congress/MESH Subject Headings

Neoplasms -- etiology; Dietary Fats -- adverse effects

Type

Thesis

Page Count

x; 140

Digital Format

PDF

Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Collection

Loma Linda University Electronic Theses and Dissertations

Collection Website

http://scholarsrepository.llu.edu/etd/

Repository

Loma Linda University. Del E. Webb Memorial Library. University Archives

Download

Share

COinS