Effects of Microencapsulated Propolis and Turmeric in Patients With Chronic Kidney Disease

The so-called Chronic Non-Communicable Diseases (NCDs) have been increasing in incidence. Among these, one can mention Chronic Kidney Disease (CKD). CKD is considered a public health problem and is characterized by an irreversible syndrome resulting from changes in the function or structure of the kidney, which has a progressive evolution.

Oxidative stress is one of the most potent inducers of inflammation, being an imbalance between the production of reactive oxygen species (ROS) and cellular antioxidant capacity, so that such imbalance can influence the activation of the nuclear factor kB (NF-κB), inflammation-associated interleukins, and tumor necrosis factor alpha 4 (TNF-α), which are promoters of cell damage and organic molecules. Patients with CKD on HD showed increased expression of NF-κB and reduced expression of Nrf2, so it is important to perform studies that propose ways to increase the performance of Nrf2, as well as reduce the activation of NF-κB. the performance of propolis and turmeric.

The study aims to evaluate the effects of supplementation of propolis and turmeric microcapsules on inflammatory markers and clinical parameters in patients with chronic kidney disease undergoing hemodialysis.

Sample calculation was performed using the G-Power 3.1 software, with a test power of 80%, considering the expression of NF-κB as the main outcome, significance level of 5% (two-tailed), effect size of 1, 32. The sample obtained consisted of 34 patients (17 in each group).

The proposed clinical study is a longitudinal randomized and double-blind (randomized controlled trial - RCT) where patients will receive capsules containing microencapsulated turmeric and propolis, twice a day, for 12 weeks. The mixture of microcapsules of propolis and turmeric will be distributed to participants in the form of hard gelatine capsules. The placebo group will receive the same amount of capsules, at the same times, containing gum arabic and corn starch. Randomization will be computerized in a 1:1 ratio.

• Anthropometric assessments, food intake, blood collections will be performed at the beginning of the follow-up and in subsequent consultations;
• The analysis of possible adverse effects will be collected through a separate analysis form;
• The assessment of food intake will be performed through the 3-day 24-hour recall;
• The assessment of nutritional status will be performed using anthropometric data;
• Blood samples will be collected in the morning, after fasting for 12 hours, before the dialysis procedure;
• NF-κB expression will be analyzed by means of peripheral blood nuclear cells (PBMCs) using real-time quantitative polymerase chain reaction (qPCR);
• For the measurement of inflammatory cytokines IL-6 and TNF-α, commercial ELISA kits will be used;
• C-reactive protein (CRP) will be determined by chemiluminescence;
• Lipid peroxidation will be estimated by determining thiobarbituric acid reactive substances (TBARS), including MDA, using the modified Ohkawa method;
• The evaluation of the total antioxidant capacity of the plasma will be determined by ELISA;

The effect of supplementation (∆) on each variable will be defined as the subject of the difference between the variable at the end of supplementation with propolis and turmeric and the value of the variable at the end of placebo administration. Statistical analyzes will be performed using SPSS version 22.0.

Inclusion criteria

• Patients with stage 5 CKD (GFR < 15 mL/min);
• On hemodialysis for more than 6 months;
• Who have arteriovenous fistula (AVF) as vascular access

Exclusion criteria

• Pregnant women;
• Smokers;
• Using antibiotics in the last 3 months;
• Using antioxidant supplements;
• Who have habitual intake of propolis, curcumin and turmeric;
• With autoimmune and infectious diseases, cancer, liver and AIDS (Acquired Immunodeficiency Syndrome)