Rice protein improves adiposity, body weight and reduces lipids level in rats through modification of triglyceride metabolism

Abstract

BackgroundTo elucidate whether rice protein can possess a vital function in improving lipids level and adiposity, the effects of rice proteins extracted by alkaline (RP-A) and α-amylase (RP-E) on triglyceride metabolism were investigated in 7-week-old male Wistar rats fed cholesterol-enriched diets for 2 weeks, as compared with casein (CAS).ResultsCompared with CAS, plasma concentrations of glucose and lipids were significantly reduced by RP-feeding (P < 0.05), as well as hepatic accumulation of lipids (P < 0.05). RP-A and RP-E significantly depressed the hepatic activities of fatty acid synthase (FAS), glucose 6-phosphate dehydrogenase (G6PD) and malate dehydrogenase (MDH) (P < 0.05), whereas the activities of lipoprotein lipase (PL) and hepatic lipase (HL) were significantly stimulated (P < 0.05), as compared to CAS. Neither lipids level nor activities of enzymes were different between RP-A and RP-E (P > 0.05). There was a significant positive correlation between protein digestibility and deposit fat (r = 0.8567, P < 0.05), as well as the plasma TG concentration (r = 0.8627, P < 0.05).ConclusionsThe present study demonstrates that rice protein can modify triglyceride metabolism, leading to an improvement of body weight and adiposity. Results suggest that the triglyceride-lowering action as well as the potential of anti-adiposity induced by rice protein is attributed to upregulation of lipolysis and downregulation of lipogenesis, and the lower digestibility of rice protein may be the main modulator responsible for the lipid-lowering action.

White Rice Intake Varies in Its Association with Metabolic Markers of Diabetes and Dyslipidemia Across Region among Chinese Adults

“…In our study, high rice consumption was strongly correlated with a healthy low-wheat diet pattern (low wheat, high fish and seafood intake) in the Central region. Another possible reason could be the up-regulation of lipolysis and the down-regulation of lipogenesis by rice protein, which has been reported in a study in rats that showed improved adiposity and body weight after rice protein feeding[36]. In addition, fried rice is commonly consumed in China by cooling steamed rice in the refrigerator overnight and stir-frying it with oil; recent studies have shown that these processes promote rice starch retrogradation, increase the resistant starch concentration of rice and reduce the rice calories[37].…”

Rice protein improves oxidative stress by regulating glutathione metabolism and attenuating oxidative damage to lipids and proteins in rats

“…The present experiment was performed in compliance with the Guidelines of the Committee for Animal Experimentation of Harbin Medical University and followed the same protocol used in previous studies (Yang et al, 2011a(Yang et al, , 2012b. Seven-week-old male Wistar rats were purchased from the Animal Center of Harbin Medical University (Harbin, China) and individually housed in metabolic cages in a room maintained at 22 ± 2°C under a 12 h light-dark cycle (07:00-19:00 light).…”

“…Longjing 26 (Rice Research Institute of Heilongjiang Academy of Agricultural Sciences, Jiamusi, China) and casein (CAS) (Gansu Hualing Industrial Group, Gansu, China) were used as the dietary protein sources in the present study. RP was prepared by the alkaline extraction method (Yang et al, 2011a(Yang et al, , 2012b.…”

“…There has been a growing emphasis on the improvement of the physiological functions of rice (Tran et al, 2004;Yang et al, 2012a), and an association between rice protein consumption and reduced plasma and liver lipid levels has been extensively demonstrated in some studies (Yang et al, 2007(Yang et al, , 2012b; Yang and Kadowaki, 2009). However, the precise mechanism by which rice protein affects lipid metabolism has not been fully established.…”

Cooked Rice Inhibits Hepatic Fat Accumulation by Regulating Lipid Metabolism–Related Gene Expression in Mice Fed a High-Fat Diet

“…[11][12][13][14] Furthermore, the ability of the rice protein to control body weight gain and plasma cholesterol levels is well established, perhaps due to the relatively low digestibility of rice protein. 34,35 For the HF-CR diet, we replaced the corn starch and sucrose present in the HF with cooked rice powder, which had 34 g of rice protein per kg total food weight. This may be helpful for decreasing body weight gain and fat accumulation.…”