Obese rats supplemented with capsaicin had 8 per cent less body weight than control animals, and displayed changes in the levels of 20 proteins associated with obesity, according to findings published in the Journal of Proteome Research.
“These changes provide valuable new molecular insights into the mechanism of the anti-obesity effects of capsaicin,” report researchers from Daegu University in Korea. “Thus, we believe that the findings presented here open new insights into the study and potential treatments for this pathology.”
The research taps into the burgeoning weight loss and management market, estimated to already be worth $7bn (€5.2bn) globally. With 50 per cent of Europeans and 62 per cent of Americans classed as overweight, the food industry is waking up to the potential of products for weight loss and management.
The slimming ingredients market can be divided into five groups based on the mechanisms of action - boosting fat burning/ thermogenesis, inhibiting protein breakdown, suppressing appetite/ boosting satiety (feeling of fullness), blocking fat absorption, and regulating mood (linked to food consumption).
Capsaicin is reported to boost heat generation by the body, which means people burn more energy. A laboratory study from the National Chung Hsing University in Taiwan, found that capsaicin may inhibit the growth of fat cells (Journal of Agricultural and Food Chemistry, 2007, Vol. 55, pp. 1730-1736), while a human study with capsaicin, in combination with green tea extracts, found that (Clinical Nutrition, doi: 10.1016/j.clnu.2009.01.010) an alternative mode of action with promotion of the feeling of fullness and sustained satiety.
The new data suggests that the compound may exert its benefits by triggering certain beneficial protein changes in the body.
Five week old rats were fed a high-fat diet in order to induce obesity and supplemented with capsaicin (10mg per kg of body weight) or saline solution (control) for nine weeks. Results showed an 8 per cent decrease in body weight in capsaicin-fed animals, compared with controls, said the researchers.
Furthermore, protein expression in fat tissue showed the up-regulation of 10 proteins and the down-regulation of another 10 proteins following supplementation with capsaicin.
“Most of the identified proteins are associated with lipid metabolism and redox regulation,” explained the researchers.
“Comparative proteome analysis of a rat model of diet-induced obesity allowed us to outline possible pathways involved in the response to capsaicin,” wrote the researchers. “Proteins identified here are involved in cellular functions that include lipid metabolism, redox processes, and signal and energy transduction.
“Some of these have already been linked to human obesity, suggesting that the newly identified proteins might also have importance in obesity and that they should be further investigated,” they added.
Source: Journal of Proteome Research
2010, Volume 9, Issue 6, Pages 2977-2987
"Proteomic Analysis for Antiobesity Potential of Capsaicin on White Adipose Tissue in Rats Fed with a High Fat Diet"