Bisacurone gel ameliorated burn wounds in experimental rats via its anti-inflammatory, antioxidant, and angiogenic properties

Purpose: To investigate putative mechanism of wound healing for chitosan-based bisacurone gel against secondary burn wounds in rats. Methods: A second-degree burn wound with an open flame using mixed fuel (2 mL, 20 seconds) was induced in Sprague Dawley rats (male, 180-220 g, n = 15, each) followed by topical treatments with either vehicle control (white petroleum gel, 1%), silver sulfadiazine (1%) or bisacurone gel (2.5, 5, or 10%) for 20 days. Wound contraction rate and paw withdrawal threshold were monitored on various days. Oxidative stress (superoxide dismutase, glutathione, malondialdehyde, and nitric oxide), pro-inflammatory cytokines (tumour necrosis factor-alpha, interleukins by enzyme-linked immunosorbent assay), growth factors (transforming growth factor-ß, vascular endothelial growth factor C using real time polymerase chain reaction and Western blot assay) levels, and histology of wound skin were assessed at the end. Results: Bisacurone gel showed 98.72% drug release with a 420.90­442.70 cps viscosity. Bisacurone gel (5 and 10%) significantly (p < 0.05) improved wound contraction rate and paw withdrawal threshold. Bisacurone gel attenuated oxidative stress, pro-inflammatory cytokines, and water content. It also enhanced angiogenesis (hydroxyproline and growth factor) and granulation in wound tissue than vehicle control. Conclusions: These findings suggested that bisacurone gel can be a potential candidate to treat burn wounds via its anti-inflammatory, antioxidant, and angiogenic properties.

Vascular endothelial growth factor C treatment for mouse hind limb lymphatic revascularization.

Spontaneous lymphatic revascularization is a challenge and the establishment of new therapeutic strategies may improve life quality for patients suffering from lymphatic disorders. This study was designed to verify if VEGFC treatment improves lymphatic vascularization in a time-dependent manner in mouse hindlimb (HL) after resection of the inguinal lymph node. Lymphatic vascular density (Vv) and length (Lv) were evaluated by stereology after immunohistochemistry. The control Group (CG) was not manipulated but received saline instead of VEGFC treatment. The surgery Group (SG) had the left inguinal lymph node resected but did not received VEGFC treatment. VEGFC Treated Group (TG) had the node resected and received VEGFC treatment. VEGFC and VEGFR3 local expression were assessed by qPCR. There was an effect of time over Vv and Lv in the SG and significant difference between CG and SG in the regions studied (proximal, medium and distal regions) of the left HL (LHL). The Lv showed significant difference between CG and SG only in the medium region. The Vv and the Lv for TG were higher than the other groups. VEGFC and VEGFR3 gene expression presented time effect in all regions of the LHL for SG and TG. Both VEGFC and VEGFR3 gene expression presented significant difference between CG and SG, between SG and TG and between CG and TG. This study showed significant decrease in lymphatic vascularization in the left hindlimb of mice after surgical removal of the inguinal lymph node and adjacent lymphatic vessels. Exogenous VEGFC could recover lymphatic vascularization through stimulating neolymphangiogenesis.

Tratamento com VEGFC para revascularização linfática em membros pélvicos de camundongos / VEGFC treatment for lymphatic revascularization of mice hindlimb

A revascularização linfática é um desafio e o estabelecimento de novas estratégias terapêuticas podem melhorar a qualidade de vida de pessoas que sofrem de distúrbios linfáticos. O objetivo deste estudo foi verificar a capacidade de tratamento com VEGFC exógeno na melhoria da vascularização linfática de uma maneira dependente do tempo em membros pélvicos (MP) de camundongos após a remoção do linfonodo inguinal. O linfonodo inguinal esquerdo foi removido cirurgicamente para mimetizar patologias com diminuição da vascularização linfática. Densidade vascular linfática (Vv) e de comprimento (Lv) foram avaliadas por imunohistoquímica, seguidas de estereologia, após a cirurgia com ou sem o tratamento com VEGFC exógeno. O grupo controle não foi manipulado, mas recebeu soro fisiológico em vez de tratamento com VEGFC exógeno. As expressões do VEGFC e FLT4 local foram avaliadas por qPCR. Houve efeito do tempo sobre Vv e Lv no Grupo Cirurgia e diferença significativa entre os grupos Controle e Cirurgia nas três regiões estudadas (região proximal, média e distal) do MP esquerdo (MPE). A Lv mostrou diferença significativa entre os grupos Controle e Cirurgia somente na região média do MPE. A Vv e a Lv para o Grupo Tratamento foram maiores do que os outros grupos em todas as regiões do MPE. A expressão gênica do VEGFC e do FLT4 apresentou efeito do tempo em todas as regiões do MPE para os grupos Cirurgia e Tratamento. Ambas as expressões gênicas do VEGFC e do FLT4 apresentaram diferença significativa entre os grupos Controle e Cirurgia, entre os grupos Cirurgia e Tratamento e entre os grupos Controle e Tratamento. Os resultados mostraram que os camundongos são bons modelos experimentais para o uso de VEGFC exógeno como terapia de revascularização linfática, e o tratamento com VEGFC exógeno aumenta vascularização linfática já após 3 dias de dano linfático.

Lymphatic revascularization is a challenge and the establishment of new therapeutic strategies may improve quality of life from those suffering from lymphatic disorders. The objective of this study was to verify the VEGFC treatment capacity in improving lymphatic vascularization in a time-dependent manner in mouse hind limb (HL) after removal of inguinal lymphnode. The left inguinal lymphnode was surgically removed to mimetize pathologies with decreased lymphatic vascularization. Lymphatic vascular density (Vv) and length (Lv) were evaluated by immunohistochemistry followed by stereology after surgery and/or VEGFC treatment. Control group was not manipulated but received saline instead of VEGFC treatment. VEGFC and FLT4 local expression were assessed by qPCR. There was effect of time over Vv and Lv in the SG and significant difference between CG and SG in the three studied regions (proximal, medium and distal region) of the left HL (LHL). The Lv showed significant difference between CG and SG only in the medium region. The Vv and the Lv for TG were higher than the other groups in all regions of LHL. VEGFC and FLT4 gene expression presented time effect in all regions of the LHL for SG and TG. Both VEGFC and FLT4 gene expression presented significant difference between CG and SG, between SG and TG, and between CG and TG. The results show that mice are good experimental models for VEGFC use as therapy for lymphatic revascularization, and VEGFC treatment increased the lymphatic vasculature already after 3 days of lymphatic damage.