Diabetic nephropathy is linked to metabolic disorders such as insulin resistance, oxidative stress, and increased biomarkers of inflammation.
Based on this, researchers from the Kashan University of Medical Sciences and the Barij Medicinal Plants Research Center in Iran sought to assess the impact of mulberry extract intake on markers of insulin metabolism, lipid concentrations, and biomarkers of inflammation and oxidative stress in diabetic nephropathy patients.
They randomly assigned 60 patients to two groups, one given 300mg of placebo twice daily and the other given 300mg of mulberry extract twice daily, for 12 weeks.
The patients' fasting blood samples were taken at the start of the study, and then 12 weeks after it had ended, in order to examine their insulin metabolism markers, lipid concentrations, and inflammation and oxidative stress biomarkers.
The researchers then observed that the patients who had been supplemented with mulberry extract exhibited significant decreases in serum triglycerides, and VLDL (very low-density lipoprotein) cholesterol concentration.
Compared to the control group, they also experienced a significant increase in HDL cholesterol concentration, and beneficial changes in serum high-sensitivity C-reactive protein, plasma glutathione, and malondialdehyde.
The researchers wrote that increased C-reactive protein levels in the blood can "reflect the process involved with inflammation", and make for a "strong independent predictor of cardiovascular (disease), myocardial infarction, and stroke among healthy individuals".
In addition, oxidative damage brought about by hydroxyl and superoxide radicals to lipids, nucleic acids and proteins may induce several diseases, including heart disease.
No effect on certain factors
The researchers wrote that the findings showed favourable effects of mulberry extract administration on high-sensitivity C-reactive protein, glutathione, serum lipid and triglyceride levels, VLDL and cholesterol concentration and malondialdehyde in diabetic nephropathy patients
However, they also noted that mulberry extract supplementation "did not affect markers of insulin metabolism, other lipid concentrations, biomarkers of inflammation, or oxidative stress".
They added that the findings of previous studies and the current one regarding the effects of mulberry extract on the aforementioned factors had been inconsistent, and thus concluded that this "might be mediated by different study designs, the differences in the population(s) studied, dosage of used mulberry, as well as the period of study".
Source: Iranian Journal of Kidney Diseases
Vol. 11, No. 6
"Metabolic Response to Mulberry Extract Supplementation in Patients With Diabetic Nephropathy"
Authors: Mohsen Taghizadeh, et al.