Healing Potential of the Marine Polysaccharides Carrageenan and Ulvan on Second-Degree Burns

Abstract

The treatment of second-degree burn wounds presents a significant clinical challenge, often characterized by prolonged healing times and risk of complications. In this study, the wound healing potential of bioactive marine sulfated polysaccharides ulvan and carrageenan formulated in gels at concentrations of 1.5%, 5.0%, and 10% w/w was evaluated. Hairless female SKH-hr2 mice (n = 7 per treatment) with burn-inflamed skin were treated with the polysaccharide-based gels, and the therapeutic efficacy was assessed using a comprehensive array of evaluation methods, including a histopathological analysis, clinical observation, photo-documentation, an image analysis, an evaluation of biophysical skin parameters, and FT-IR spectroscopy. Our findings indicate that the 10% w/w carrageenan gel exhibited significant enhancement in wound healing, particularly in the early stages of the healing process. This was evidenced by the restoration of the α-helix structure of collagen and the configuration of glycosaminoglycans, as demonstrated by FT-IR absorption bands of the skin both in vivo and ex vivo. Furthermore, the 5% w/w ulvan gel also demonstrated notable efficacy in promoting wound healing, particularly in the later stages of the healing process. These results suggest that carrageenan and ulvan gels hold promise for improving the efficiency of wound healing in second-degree burn wounds. Our study contributes to the understanding of the therapeutic potential of marine polysaccharides and provides insights into their mechanism of action in promoting wound healing.

Keywords: carrageenan; in vivo mice model; infrared spectroscopy; partial-thickness burn; ulvan; wound care.

Figure 1

Representative images depicting the wound areas of mice receiving no treatment; vehicle; 1,5%, 5%, and 10% w/w of ulvan gels; and 1,5%; 5%, and 10% w/w of carrageenan gels, captured on days 1, 3, 6, 15, 21, 23, and 26. Among the treatment groups, mice treated with the 10% w/w carrageenan gel exhibited the most favorable clinical outcomes followed by those treated with 5% w/w ulvan gel.

Figure 2

(A) Histogram of wound area reduction in relation to time. (B) Wound healing rate expressed using linear regression analysis for two distinct time periods, i.e., days 1 to 15, and 15 to 26; * p < 0.05, ** p < 0.01, *** p < 0.001.

Figure 3

Hematoxylin and eosin-stained sections of mice skin at the burn wound area for mice receiving different treatments (100×). Blue arrows depict mild inflammation in the 10% w/w carrageenan and 5% w/w ulvan groups; black arrows depict moderate inflammation in the 1.5% and 10% w/w ulvan groups, as well as in the 1.5% and 5% w/w carrageenan groups; red arrows depict severe inflammation in the control and vehicle groups; ellipses depict epidermal hyperplasia in the vehicle and 5% w/w carrageenan group.

Figure 4

Histograms of (A) hemoglobin and (B) skin texture of mice receiving different treatments in relation to time (* p < 0.05, ** p < 0.01).

Figure 5

Histograms of (A) hydration, (B) transepidermal water loss (TEWL), and (C) skin thickness of different treatments at the beginning and the end of the experimental procedure (* p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001).

Figure 6

FT-IR spectra of mice skin treated with carrageenan and ulvan at various concentrations during the final stage of wound healing.

Figure 7

FT-IR spectra of mice skin during wound healing: (1) spectrum of mice skin treated with 5% w/w ulvan gel, (2) spectrum of mice skin treated with 10% w/w carrageenan gel, and (3) spectrum resulting from subtraction of spectrum 1 from spectrum 2.