Cardioprotective Effects of Leucine Supplementation against Doxorubicin-Induced Cardiotoxicit.

Doxorubicin is one of the most important antitumor drugs used in oncology; however, its cardiotoxic effect limits the therapeutic use and raises concerns regarding patient prognosis. Leucine is a branched-chain amino acid used in dietary supplementation and has been studied to attenuate the toxic effects of doxorubicin in animals, which increases oxidative stress. Oxidative stress in different organs can be estimated using several methods, including catalase expression analysis. This study aimed to analyze the effect of leucine on catalase levels in rat hearts after doxorubicin administration. Adult male Wistar rats were separated into two groups: Standard diet (SD) and 5% Leucine-Enriched Diet (LED). The animals had free access to diet from D0 to D28. At D14, the groups were subdivided in animals injected with Doxorubicin and animals injected with vehicle, until D28, and the groups were SD, SD + Dox, LED and LED + Dox. At D28, the animals were submitted do Transthoracic Echocardiography and euthanized. Despite Dox groups had impaired body weight gain, raw heart weight was not different between the groups. No substantial alterations were observed in macroscopic evaluation of the heart. Although, Doxorubicin treatment increased total interstitial collagen in the heart, which in addition to Type I collagen, is lower in LED groups. Western blot analysis showed that catalase expression in the heart of LED groups was lower than that in SD groups. In conclusion, leucine supplementation reduced both the precocious Dox-induced cardiac remodeling and catalase levels in the heart.

Evaluation of 4% stabilized Sodium Hypochlorite activity in the repair of cutaneous excisional wounds in mice.

Wounds are conditions largely present in the clinical routine, and even though frequent, their complete resolution can be challenging. Several solutions can aid or stimulate the healing process, and for this reason, this work used a stabilized solution of 4% sodium hypochlorite for the treatment of excisional wounds in mice. This study was carried out in two distinct stages: in the first stage, the optimal concentration of the chlorinated solution was determined by using the sponge implantation technique in mouse subcutaneous tissue to evaluate the dose-response curve; and in the second phase, this concentration was tested in an experimental model of excisional skin wounds in mice. Soluble collagen, hemoglobin, myeloperoxidase (MPO) and N-acetyl-ß-D-glycosaminidase (NAG) activity were assessed, and total, type I and type III collagen deposition were quantified in both stages. Based on the results presented in the sponge implantation study, the chlorinated solution at 150 ppm (0.015%) was chosen for use in a preclinical trial of skin healing in mice. At 1, 3, 7 and 14 days of treatment, the % wound area repair in the group treated with 150 ppm chlorinated solution was higher when compared to the control group, with statistical differences at all time points (*p≤ 0.05 and **p≤ 0.01). 150 ppm chlorinated solution obtained from a stabilized 4% sodium hypochlorite solution was effective in accelerating cutaneous excision wound repair in mice, showing a positive influence on tissue repair.