Six new studies on raspberry’s health benefits
Six new studies on raspberry's health benefits were presented at the Experimental Biology conference in San Diego in April 2016. The target berry species was American raspberry (Rubus strigosus), a close relative of European raspberry (Rubus idaeus). Results were published as conference abstracts in "Federation of American Societies for Experimental Biology".
1. Raspberry and cardiovascular disease
For 8 weeks, rats were fed a high-fat diet containing either freeze-dried whole raspberry powder or added sugars. According to results, raspberry powder diet reduced fasting triglycerides and fasting glucose but did not appear to affect fasting insulin, fasting low-density lipoprotein, or body weight gain. Hearth rate, left ventricular enlargement and wall thickening were reduced. Left ventricular enlargement is a significant risk factor to hearth failure. Red raspberries could play an important part for dietary management of cardiometabolic risk.
Source: Kirakosyan, A., Seymour, E.M., Kondoleon, N., Wolforth, J. & Bolling, S. (2016): Cardioprotective effects of red raspberries in obesity-prone rats. Federation of American Societies for Experimental Biology, vol. 30 (1).
2. Raspberry and hepatic gene expression
Eight groups of mice were provided either low-fat diet or high-fat diet combined with different raspberry products (raspberry juice concentrate, raspberry puree concentrate, raspberry freeze-dried powder, ellagic acid, raspberry ketone) for 10 weeks. Intake of raspberry products significantly reduced weight gain during the study. Furthermore, glucose tolerance was improved with raspberry supplement. Intake of raspberry foods exerted positive effects on gene expression in the liver. E.g. raspberry ketone diet regulated 30 genes even so that the pattern of expression more closely resembled that of the mice fed on low-fat diet rather than the high-fat fed mice. Surely many biological mechanisms are responsible, but clearly hepatic gene expression is being altered in a favourable manner with the consumption of raspberries.
Source: Shay, N.F., Luo, T., Miranda, O. & Adamson, A. (2016): Intake of whole raspberries and the raspberry phytochemicals, ellagic acid and raspberry ketone reduces adiposity, improves glucose control and changes hepatic gene expression profiles in high-fat fed mice. Federation of American Societies for Experimental Biology, vol. 30 (1).
3. Raspberry and weight maintenance
Mice were randomized into 4 groups receiving either control or high-fat diet supplemented with or without freeze dried raspberry for 12 weeks. High-fat diet increased significantly body weight, which can be alleviated by raspberry supplementation. In addition, blood glucose was elevated in high-fat diet group, which was reduced by raspberry supplementation. In addition, raspberry improved glucose tolerance and insulin sensitivity, reduced abundance of lipid droplets in the liver and decreased serum triglyceride level. As conclusion, raspberry supplementation reduced adiposity and improved glucose and lipid homeostasis.
Source: Zhu, M., Kang, Y., García, M.P.G., Liang, X., Xue, Y., Pan, H. & Du, M. (2016): Dietary raspberries ameliorate metabolic syndromes in diet-induced obese mice. Federation of American Societies for Experimental Biology, vol. 30 (1).
4. Raspberry and diabetes-related complications
Obese diabetic mice were divided into two groups for eight weeks. Control group was fed with basic food, but other group received also supplemented freeze-dried raspberries. According to results, plasminogen activator inhibitor-1 (PAI-1) was lower in the raspberry compared to the control group. High PAI-1 has been linked to higher risk for thrombosis and arteriosclerosis. Results demonstrate that raspberry consumption helps to decrease diabetes-related complications and hearth disease.
Source: Noratto, G., Chew, B. & Mencia, A. (2016): Effects of raspberry dietary supplementation on risk biomarkers of diabetes related complications and hearth disease in diabetic mice. Federation of American Societies for Experimental Biology, vol. 30 (1).
5. Raspberry and fatty liver disease
In addition to anthocyanins, ellagic acid is another polyphenolic constituent naturally occurring in many fruits and berries. The highest ellagic acid content is found in berries of Rubus and Fragaria species (raspberry, cloudberry, arctic raspberry, and strawberry). The aim of this study was to investigate the binding ability of ellagic acid to the human PPARa-receptor, which regulates the lipid metabolism of liver. The results demonstrated direct ligand binding of ellagic acids to the PPARa-receptor and suggest that ellagic acids may have the potential to enhance fatty acid oxidation by transactivation of the PPARa pathway. The future studies will show whether this finding can be utilized in prevention of non-alcoholic fatty liver disease (NAFLD).
Source: Sasaki, G., Luo, T. & Shay, N.F. (2016): Ellagic acid and quercetin are high-affinity ligands of human peroxisome proliferator-activated receptor alpha in an in-vitro competitive bidding assay. Federation of American Societies for Experimental Biology, vol. 30 (1).
6. Raspberries and bone health
An osteoclast is a type of bone cell that breaks down bone tissue. Osteoblasts are cells that synthesize bone.Osteoclasts are stimulated by a cytokine known as RANKL. According to earlier studies, polyphenols have demonstrated anti-inflammatory effects in various tissues. The aim of this study was to examine whether raspberry polyphenols could inhibit the proliferation and activity of RANKL-induced osteoclasts by using mouse macrophage cells. Results suggested that the polyphenols associated with red raspberry would inhibit the negative effects of osteoclasts on bone health.
Source: Thomas, A., South, S., Imrhan, V., Prasad, C., Vijayagopal, P. & Juma, S. (2016): Inhibitory effects of red raspberry polyphenols on osteoclastogenesis in RANKL-stimulated RAW264.7 murine macrophages. Federation of American Societies for Experimental Biology, vol. 30 (1).
Anni Koskela, Arctic Flavours Association
+358 40 164 6177
ylipaino maksa kolesteroli sydän- ja verisuonitaudit diabetes polyfenolit vadelma cardiovascular disease cholesterol diabetes polyphenols Keywords: raspberry luusto liver obesity bone health