The effect of sea buckthorn supplement on oral health, inflammation, and DNA damage in hemodialysis patients: a double-blinded, randomized crossover study.

OBJECTIVE

Chronic kidney disease is associated with inflammation, oxidative stress, malnutrition, poor oral health, and mouth dryness. The objective of this study was to evaluate effects of sea buckthorn oil (SBO) extract, which is rich in vitamins, phytochemicals, and polyunsaturated fatty acids, on oxidative stress, saliva production, and inflammation in hemodialysis patients.

METHODS

This was a randomized, double-blinded, and placebo-controlled crossover study (2 × 8 weeks, 4-week washout). The study subjects were hemodialysis patients (n = 45) recruited from the Department of Renal Medicine at Karolinska University Hospital in Stockholm.

METHODS

The patients received 4 capsules per day, each containing 500 mg of SBO or placebo, for 8 weeks. They were then crossed over to the other treatment after a 4-week washout period. Salivary gland biopsies, saliva, and blood samples were collected before and after each treatment period. Main outcomes were DNA breaks and oxidative DNA lesions in minor accessory salivary glands, salivary flow rates, and inflammation markers in blood (high-sensitivity C-reactive protein, antitrypsin, orosomucoid in plasma, leukocytes in blood). Blood markers including creatinine, urea in plasma, and hemoglobin in blood were investigated.

RESULTS

The results showed no significant changes in DNA breaks, oxidative DNA lesions, salivary flow rates, or inflammation after SBO supplementation. However, plasma levels of phosphate and sodium increased and plasma levels of iron decreased.

CONCLUSIONS

In conclusion, SBO supplementation as performed in this study did not protect against oxidative stress, nor improve oral health or inflammation status in hemodialysis patients.