Prevention of colon carcinogenesis by apple juice in vivo: Impact of juice constituents and obesity

Abstract

It is estimated that 75-85% of all chronic diseases are linked to lifestyle-related and environmental factors. The development of colon cancer is positively associated with obesity and inversely associated with the intake of dietary fibre, fruit and vegetable. Apple juice is the most widely consumed fruit beverage in Germany. It contains a specific spectrum of polyphenols and other components that may reduce the risk of colon cancer. Epidemiologic studies suggest an inverse correlation between apple consumption and colon cancer risk, although the mechanisms for these observations are not clear. The present review summarizes the preventive potential of apple juices and different apple constituents on biomarkers related to colon carcinogenesis with special focus on the in vivo evidence and the cancer promoting condition of obesity. However, under the cancer promoting condition of obesity, apple juice did not show cancer-preventive bioactivity. In our experiments a cancer-preventive bioactivity of apple juice is lacking in rats under the cancer-promoting condition of obesity. To further investigate, whether this lack of efficacy observed in obese rats might be representative for obese individuals human intervention studies on high risk groups such as obese or diabetic individuals are of interest and will be conducted.

Nutritional and health-promoting properties of tropical and subtropical fruits

“…For example, epidemiological studies suggest an inverse correlation between apple consumption and colon cancer risk. However, under the cancer promoting condition of obesity, apple juice did not show cancer-preventive bioactivity (Koch et al , 2009). Some intervention trials with pure carotenoids did not show any effect on cancer risk, and in fact other trials have shown increased risk (Stahl and Sies, 2005).…”

A theoretical study on predicted protein targets of apple polyphenols and possible mechanisms of chemoprevention in colorectal cancer

“…Among food categories rich in antioxidant components, apple fruits seem particularly interesting, both for the number of varieties and their high content of antioxidants456, and for their known chemo-preventive effects against colorectal cancer78910. Recently, the content of phenolic compounds in different apple varieties has been compared11.…”

Apple juices from ancient Italian cultivars: a study on mature endothelial cells model

“…Moreover, apples are rich in phenolic compounds [10], that are widely discussed as promising candidates for prevention of cancer and inflammation [2,11]. Apple and AJ are reported to increase antioxidant levels in humans [12] and have been tested as cancer chemopreventive both in vitro [13] and in humans [14,15]. Beside cancer chemoprevention, apple polyphenols have been reported to have other in vitro and in vivo physiological properties, such as antiallergenic and anti-caries activity, and inhibitory activity against some enzymes and receptors involved in pathological processes [2,16].…”