Tocotrienol-rich vitamin E from palm oil (Tocovid) and its effects in diabetes and diabetic retinopathy: a pilot phase II clinical trial

  • Yilynn Chiew School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia; Tropical Medicine and Biology Platform, School of Science, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor, Malaysia
  • Suzanne May Quinn Tan School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia; Tropical Medicine and Biology Platform, School of Science, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor, Malaysia
  • Badariah Ahmad School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia; Tropical Medicine and Biology Platform, School of Science, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor, Malaysia
  • Sim Ee Khor Thomson Hospital Kota Damansara, Petaling Jaya, Selangor; Malaysia
  • Khalid Abdul Kadir School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia; Tropical Medicine and Biology Platform, School of Science, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor, Malaysia
Keywords: advanced glycation end products, carboxymethyl-lysine, diabetic retinopathy, palm oil, tocotrienol, vitamin E

Abstract

Aim: To identify the effects of tocotrienol-rich vitamin E from palm oil (Tocovid) on diabetic retinopathy (DR) in patients with type 2 diabetes.

Materials and methods: The intervention group (n = 21) received 200 mg Tocovid twice daily while the control group (n = 22) received placebo twice daily for 8 weeks. Changes in retinal photography by conventional grading and novel quantification of retinal hemorrhage were assessed. Changes in serum biomarkers advanced glycation end products (AGE) general, sRAGE (soluble receptor of AGE), Nε-CML (specific type of AGE), and cystatin C were evaluated.

Results: A novel technique to quantify retinal hemorrhage had a strong positive correlation with conventional grading of DR in both eyes at baseline and at the end of the study. Eight-week supplementation of Tocovid resulted in significant reduction in retinal hemorrhage in the right eye. Liver enzymes and ALT significantly reduced. No significant changes in grade of DR, serum biomarkers, HbA1c, blood pressure, renal profile, and lipid profile were observed.

Conclusions: Tocovid is a potential adjunct to current treatment of DR and fatty liver disease. A novel method of quantifying retinal hemorrhage is a potential technique for assessing disease severity of DR, particularly the early changes.

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Published
2021-04-16
How to Cite
Chiew, Y., Tan, S., Ahmad, B., Khor, S. E., & Abdul Kadir, K. (2021). Tocotrienol-rich vitamin E from palm oil (Tocovid) and its effects in diabetes and diabetic retinopathy: a pilot phase II clinical trial. Asian Journal of Ophthalmology, 17(4), 375-399. https://doi.org/10.35119/asjoo.v17i4.698