Dose-Related Regulatory Effect of Raspberry Polyphenolic Extract on Cecal Microbiota Activity, Lipid Metabolism and Inflammation in Rats Fed a Diet Rich in Saturated Fats

Abstract

The amount of berry polyphenols required to exert health-promoting effects seems to be difficult to achieve by fresh fruit ingestion, so polyphenol-rich extracts could be considered a dietary alternative. In the present study, laboratory rats were fed high-fat diets supplemented with 0.1 or 0.3% raspberry polyphenols from pomace, with the former dose reflecting the amount of polyphenols consumed with a glass of fresh raspberries. It was hypothesized that beneficial changes in blood and hepatic tissue related to lipid metabolism would accompany both treatments, but the health-promoting effect would be more noticeable with the higher dose of extract. This hypothesis was confirmed, and the high dose of raspberry polyphenols was better than the low dose extract in terms of decreased epididymal white adipose tissue weight, hepatic triglyceride content, PPARγ and SREBP-1c expression in the liver, and plasma IL-6 concentration, as well as increased acetic acid concentration in the cecal digesta. These effects might be partially associated with the enhanced content of ellagitannin and anthocyanin metabolites found in the blood plasma of rats administered the high dose of the extract. The results showed that this extract could be considered a dietary vehicle to provide an amount of raspberry polyphenols that could promote health.

Exploring the potential mechanism of Rubus corchorifolius L. fruit polyphenol-rich extract in mitigating non-alcoholic fatty liver disease by integration of metabolomics and transcriptomics profiling

“…Nowadays, there has been a growing interest in understanding the effect of phenolic compounds, such as cyanidin derived from red-colored berries, in alleviating HFD-induced NAFLD. 19 This research highlights the dual lipid/glucose-reducing capabilities of RCE and its strong protective impact on HFD-induced NAFLD in mice. Surprisingly, the evidence shows that high-dose RCE administration in normal mice fed a normal diet did not cause any bodily harm or have any obvious effect on fasting blood glucose levels.…”

Prebiotics Together with Raspberry Polyphenolic Extract Mitigate the Development of Nonalcoholic Fatty Liver Diseases in Zucker Rats

“…To the experimental diet, 0.3% polyphenols were added. According to the results from previous studies, this amount of raspberry polyphenols and their combination with FOSs showed the most favorable effect against the first stage of NAFL in Wistar rats [ 15 , 19 ]. The diet compositions are shown in Table 1 .…”