Chitosan-microencapsulated rhEGF in promoting wound healing

2021 ◽  
Vol 30 (Sup9a) ◽  
pp. IXi-IXxi
Author(s):  
Hsin-Chung Tsai ◽  
Christine Sheng ◽  
Le-Shin Chang ◽  
Zhi-Hong Wen ◽  
Ching-Yin Ho ◽  
...  
Keyword(s):  
Wound Healing ◽  
Type I Collagen ◽  
Normal Skin ◽  
Hair Follicles ◽  
Type Iii Collagen ◽  
Type I ◽  
Treatment Groups ◽  
Spray Solution ◽  
Significant Difference ◽  
Spray Treatment

Aims: Chitosan and epidermal growth factor (EGF) have been shown to improve wound healing. This study investigates the healing effects of a spray solution (NewEpi, JoyCom Bio-Chem Co. Ltd., Taiwan) containing recombinant human EGF (rhEGF) delivered via a newly patented technology—chitosan microencapsulated nanoparticles. Methods: On Wistar rats, two full-thickness wounds on the dorsum bilateral of the spine were created. The rats were randomised to the following treatment groups: hydrogel, wet dressing, foam, rhEGF spray and rhEGF spray+foam. Sterile dressings were applied and changed daily. A total of 2μg of rhEGF was administered in two sprays during each dressing change. All animals were euthanised on day 14. Tissue samples were taken from the wound bed, including an area of 2cm surrounding the wound margin for histological evaluations. Results: Wounds treated with the rhEGF spray achieved the greatest size reduction by day 14 compared with other types of conventional dressings. An overall significant difference in levels of collagen synthesis existed between groups (p<0.01). Pair-wise comparisons showed that the rhEGF spray treatment significantly promoted higher levels of mature Type I collagen than any other conventional dressings (p<0.01), whereas non-rhEGF treatments resulted in higher levels of Type III collagen. The regenerated tissue in rhEGF spray treatment groups was also in alignment with that of normal skin. Epidermis, dermis and hair follicles were easily observed in wounds treated with the rhEGF spray. Conclusion: The major challenge of topical application of rhEGF was overcome by using a new drug delivery technology: chitosan–rhEGF nanoparticles. The positive healing effects observed in this study suggest the therapeutic potentials of this novel rhEGF topical spray solution.

scholarly journals The effects of posterior cruciate ligament rupture on the biomechanical and histological characteristics of the medial collateral ligament: an animal study

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Wen-qing Xie ◽  
Miao He ◽  
Yu-qiong He ◽  
Deng-jie Yu ◽  
Hong-fu Jin ◽  
...  
Keyword(s):  
Posterior Cruciate Ligament ◽  
Medial Collateral Ligament ◽  
Type I Collagen ◽  
Cruciate Ligament ◽  
Collagen Fibers ◽  
Type Iii Collagen ◽  
Type I ◽  
Collateral Ligament ◽  
Intact Group ◽  
Significant Difference

Abstract Background To investigate the effect of complete rupture of the posterior cruciate ligament (PCL) on the biomechanics and histology of the medial collateral ligament (MCL). Materials and methods Seventy-two male rabbits were randomly divided into two groups: the ruptured group was treated with complete PCL amputation, while the intact group was only subjected to PCL exposure without amputation. Eighteen rabbits were randomly sacrificed at 8, 16, 24, and 40 weeks after the operation, and their specimens were processed for mechanical tensile testing, nano-indentation experiments, hematoxylin-eosin (HE) staining, and picrosirius-polarization staining. Results There was no significant difference in the length and maximum displacement of the MCL between the ruptured group and the intact group at each time point. The maximum load of the ruptured group was significantly smaller than that of the intact group at 40 W. The elastic modulus and micro-hardness of the ruptured group increased significantly at 24 W and decreased significantly at 40 W. At 16 W and 24 W after PCL rupture, the number of type I collagen fibers and type III collagen fibers in the MCL of the ruptured group was significantly increased compared with that of the intact group. While the type I collagen fibers of the ruptured group were significantly decreased compared with the intact group at 40 W, there was no significant difference in type III collagen fibers between the ruptured group and the intact group. Conclusion PCL rupture has no significant effect on the mechanical and histological properties of MCL in a short period of time under physiological loading, but the histological and mechanical properties of MCL decrease with time.

scholarly journals Heat delays skin wound healing in mice

2016 ◽  
Vol 242 (3) ◽  
pp. 258-266 ◽  
Author(s):  
Marco Aurélio dos Santos-Silva ◽  
Eduardo Tavares Lima Trajano ◽  
Fernanda Seabra Schanuel ◽  
Andréa Monte-Alto-Costa
Keyword(s):  
Wound Healing ◽  
Protein Expression ◽  
Visible Light ◽  
Type I Collagen ◽  
In Vivo Studies ◽  
Type Iii Collagen ◽  
Type I ◽  
Skin Wound Healing ◽  
Thermal Chamber

In vivo studies have shown that the combination of infrared radiation (IR) and visible light (VIS) is responsible for the activation of metaloproteinases, causing matrix degradation and damage to healthy skin. However, the role of heat originating from the VIS spectrum on wound healing remains poorly understood. Our objective was to investigate the macroscopic, microscopic and biochemical effects of heat induced by visible light on cutaneous wound healing in mice. Male mice were anesthetized, subjected to a cutaneous excisional wound and divided into two groups ( n = 10/group) exposed to 23℃ or 43℃ in a thermal chamber for 30 min every other day, for 13 days. On day 14, the animals were sacrificed, and their lesions were processed for histochemistry, immunohistochemistry and protein expression analysis. The wound area was 42% greater 11 days ( p < 0.01) and 29% greater 14 days ( p < 0.001) after wounding in the 43℃ group than in the 23℃ group. The 43℃ group presented a lower (17%) percentage of reepithelialized wounds ( p < 0.001) 14 days after wounding. The length of the epidermal gap was greater in the 43℃ group ( p < 0.01). The volume density of myofibroblasts and the number of F4/80-positive macrophages was greater in the 43℃ group ( p < 0.05). The 43℃ group showed increased protein expression of type III collagen ( p < 0.001), decreased protein expression of type I collagen ( p < 0.05), increased MMP-1 expression ( p < 0.05), and decreased MMP-2 activity ( p < 0.001). The protein expression of fibrillin-1 ( p < 0.001), MMP-12 ( p < 0.05), TGF-β 1/2/3 ( p < 0.01) and ERK activation ( p < 0.05) was increased in the 43℃ group. Our results suggest that heat delays the stages of wound healing in mice.

scholarly journals Effects of Concentrated Growth Factor and Nanofat on Aging Skin of Nude Mice Induced by D-Galactose

2021 ◽  
pp. 425-435
Author(s):  
W SUN ◽  
T LI ◽  
H YAO ◽  
L KANG ◽  
F DONG
Keyword(s):  
Growth Factor ◽  
Nude Mice ◽  
Type I Collagen ◽  
Elastic Fiber ◽  
Control Group ◽  
Type Iii Collagen ◽  
Type I ◽  
Model Group ◽  
Treatment Groups ◽  
Aging Skin

This investigation studied the effect of concentrated growth factor and nanofat on aging skin of nude mice induced by D-galactose. BALB/c mice were randomly divided into five groups: 5 mice in the control group were fed normally without any intervention, 9 mice were treated with concentrated growth factor (CGF), 9 mice were treated with nanofat (NF), 9 mice were treated with CGF+NF, and 9 mice in the model group (no treatment after subcutaneous injection of D-galactose). Relevant indicators are measured and recorded. In skin and serum, SOD and GSH content in the model group were significantly lower than those in other groups (P<0.05), and the MDA of the three treatment groups was significantly lower than that of the model group (P<0.05). Compared with the control group, the contents of total collagen, type I collagen and type III collagen in the NF group and model group were decreased in different degrees (P<0.05); the contents of elastin and elastic fiber in the skin of nude mice in the model group and NF group were significantly decreased. Compared with the model group, he number of CD31 and VEGF in the treatment group was significantly increased (P<0.01); the skin AGE content of three treatment groups was significantly lower (P<0.05). These findings suggest that concentrated growth factor and nanofat may have a significant effect on delaying aging skin induced by D-galactose in nude mice.

scholarly journals The Effect of Glucagon-Like Peptide-2 Receptor Agonists on Colonic Anastomotic Wound Healing

2010 ◽  
Vol 2010 ◽  
pp. 1-12 ◽  
Author(s):  
Heather A. Redstone ◽  
William D. Buie ◽  
David A. Hart ◽  
Laurie Wallace ◽  
Pamela J. Hornby ◽  
...  
Keyword(s):  
Wound Healing ◽  
Type I Collagen ◽  
Therapeutic Potential ◽  
Bursting Pressure ◽  
Type Iii Collagen ◽  
Type I ◽  
Mrna Levels ◽  
Hypoxic Conditions ◽  
Glucagon Like Peptide ◽  
Anastomotic Strength

Background. Glucagon-like peptide 2 (GLP-2) is an intestinal specific trophic hormone, with therapeutic potential; the effects on intestinal healing are unknown. We used a rat model of colonic healing, under normoxic, and stress (hypoxic) conditions to examine the effect of GLP-2 on intestinal healing.Methods. Following colonic transection and reanastomosis, animals were randomized to one of six groups (n=8/group): controls, native GLP-2, long-acting GLP-2 (GLP-2- MIMETIBODY, GLP-2-MMB), animals were housed under normoxic or hypoxic (11%  O2) conditions. Animals were studied five days post-operation for anastomotic strength and wound characteristics.Results. Anastomotic bursting pressure was unchanged by GLP-2 or GLP-2-MMB in normoxic or hypoxic animals; both treatments increased crypt cell proliferation. Wound IL-1βincreased with GLP-2; IFNγwith GLP-2 and GLP-2-MMB. IL-10 and TGF-βwere decreased; Type I collagen mRNA expression increased in hypoxic animals while Type III collagen was reduced with both GLP-2 agonists. GLP-2 MMB, but not native GLP-2 increased TIMP 1-3 mRNA levels in hypoxia.Conclusions. The effects on CCP, cytokines and wound healing were similar for both GLP-2 agonists under normoxic and hypoxic conditions; anastomotic strength was not affected. This suggests that GLP-2 (or agonists) could be safely used peri-operatively; direct studies will be required.

scholarly journals The influence of nicotine on the population of fibroblasts in cutaneous scars in rats

2009 ◽  
Vol 24 (6) ◽  
pp. 466-470 ◽  
Author(s):  
Maria de Lourdes Pessole Biondo-Simões ◽  
Natali Weniger Spelling ◽  
Sérgio Issamu Ioshii ◽  
Rachel Biondo-Simões ◽  
João Carlos Domingues Repka
Keyword(s):  
Group Treatment ◽  
Type I Collagen ◽  
Control Group ◽  
Histopathological Study ◽  
Type Iii Collagen ◽  
Type I ◽  
Immunohistochemical Technique ◽  
Significant Difference ◽  
Collagen Density ◽  
Collagen Analysis

PURPOSE: To study the collagen density and the population of fibroblasts in cutaneous injuries in rats under the influence of nicotine. METHODS: The scars of abdominal wounds in rats were analyzed. 2 mg/kg/d of nicotine was administered to the animals in the experiment group and the solution used as a vehicle for the animals in the control group. Treatment was begun seven days prior to surgery and maintained for seven or fourteen days following surgery. The removed scars were prepared for histopathological study. Histological cuts were stained by Sirius Supra red F3BA for collagen analysis and submitted to the examination using the immunohistochemical technique, which enabled us to recognize the population of fibroblasts. RESULTS: No significant difference was found in type I collagen density after seven days (p=0.912), nor after fourteen days (p=0.211). The control group had more type III collagen after seven days (p=0.004), but after fourteen days there was no significant difference (p=0,720). The total quantification of collagen, although higher in the control group, was not significantly so at any time during the study (p=0.103 after seven days and p=0.549 after fourteen days). The average of fibroblasts per field was lower after seven days (p=0.0001) and after fourteen days (p=0.0000). CONCLUSION: Under the conditions of this experiment, nicotine reduced the fibroblast population without modifying collagen density significantly.

scholarly journals Effects of chitosan-collagen dressing on wound healing in vitro and in vivo assays

2021 ◽  
Vol 19 ◽  
pp. 228080002198969
Author(s):  
Min-Xia Zhang ◽  
Wan-Yi Zhao ◽  
Qing-Qing Fang ◽  
Xiao-Feng Wang ◽  
Chun-Ye Chen ◽  
...  
Keyword(s):  
Wound Healing ◽  
Wound Dressing ◽  
Type I Collagen ◽  
Inhibition Zone ◽  
Negative Control ◽  
Type I ◽  
Nih3t3 Cells ◽  
Post Operation

The present study was designed to fabricate a new chitosan-collagen sponge (CCS) for potential wound dressing applications. CCS was fabricated by a 3.0% chitosan mixture with a 1.0% type I collagen (7:3(w/w)) through freeze-drying. Then the dressing was prepared to evaluate its properties through a series of tests. The new-made dressing demonstrated its safety toward NIH3T3 cells. Furthermore, the CCS showed the significant surround inhibition zone than empty controls inoculated by E. coli and S. aureus. Moreover, the moisture rates of CCS were increased more rapidly than the collagen and blank sponge groups. The results revealed that the CCS had the characteristics of nontoxicity, biocompatibility, good antibacterial activity, and water retention. We used a full-thickness excisional wound healing model to evaluate the in vivo efficacy of the new dressing. The results showed remarkable healing at 14th day post-operation compared with injuries treated with collagen only as a negative control in addition to chitosan only. Our results suggest that the chitosan-collagen wound dressing were identified as a new promising candidate for further wound application.

Influence of Cisplatin on Wound Healing—An Experimental Model

1986 ◽  
Vol 95 (2) ◽  
pp. 210-212 ◽  
Author(s):  
Charles M. Stiernberg ◽  
R. Mark Williams ◽  
James A. Hokanson
Keyword(s):  
Wound Healing ◽  
Chemotherapeutic Agents ◽  
Optimal Time ◽  
Subcutaneous Injections ◽  
Treatment Groups ◽  
Cell Counts ◽  
Proliferative Stage ◽  
Significant Difference ◽  
Surgical Staples ◽  
Outbred Mice

Recent clinical studies have shown that adjuvant chemotherapy may improve response rates to treatment for advanced head and neck carcinomas. Given preoperatively, some chemotherapeutic agents adversely affect wound heallng. The specific purpose of this study was to evaluate the Influence of cisplatin on wound healing when it is given preoperatively. Forty-four Swiss outbred mice were divided into control and treatment groups. One week before surgery, the treatment group received cisplatin (2 mg/ kg body weight) by subcutaneous injections on 2 consecutive days. Each control animal was given an equal volume of normal saline. A 1.5 cm transverse incision was made in each animal, and wounds were closed with surgical staples. The mean woundbreaking strength was determined for a minimum of 5 treatment and 5 control mice on postoperative days 6, 10, 13, and 16. Serum creatinine, blood cell counts, and changes in weight were also monitored. Results showed wound strength on postoperative day 10 to be significantly reduced in mice treated with cisplatin (P < 0.05). There was no significant difference for wound strength on any other days and all other variables were simllar between both groups. In conclusion, cisplatin has an adverse effect on wound healing, the peak of which probably occurs during the proliferative stage of wound healing. Further studies are needed to determine the optimal time for surgery after preoperative chemotherapy. All new chemotherapeutic agents, particularly those being considered in a preoperative regimen, should be tested in this manner.

scholarly journals Characterization of porcine osteonectin extracted from foetal calvariae

1988 ◽  
Vol 253 (1) ◽  
pp. 139-151 ◽  
Author(s):  
C Domenicucci ◽  
H A Goldberg ◽  
T Hofmann ◽  
D Isenman ◽  
S Wasi ◽  
...  
Keyword(s):  
Amino Acids ◽  
Secondary Structure ◽  
Type I Collagen ◽  
Culture Shock ◽  
Gel Filtration ◽  
Alpha Helix ◽  
Type I ◽  
Homologous Proteins ◽  
Compact Structure ◽  
Significant Difference

Osteonectin, extracted from foetal porcine calvariae with 0.5 M-EDTA, was purified to homogeneity by using gel filtration and polyanion anion-exchange fast protein liquid chromatography under dissociative conditions without the need of reducing agents. The purified protein migrated with an Mr of 40,300 on SDS/polyacrylamide gels and was similar to bovine osteonectin in both amino acid composition and in its ability to bind to hydroxyapatite in the presence of 4 M-guanidinium hydrochloride (GdmCl). However, unlike the bovine protein, porcine osteonectin did not bind selectively to hydroxyapatite when EDTA tissue extracts were used. In addition, purified porcine osteonectin did not show any apparent affinity for either native or denatured type I collagen, but did bind to serum albumin. Primary sequence analysis revealed an N-terminal alanine residue, with approximately one-half of the subsequent 35 residues identified as small hydrophobic amino acids and one-quarter as acidic amino acids. The only significant difference between the N-terminal sequences of the bovine and porcine proteins was the deletion of the tripeptide Val-Ala-Glu in porcine osteonectin. In contrast with bovine osteonectin, far-u.v.c.d. of porcine osteonectin revealed considerable secondary structure, of which 27% was alpha-helix and 39% was beta-sheet. Cleavage of the molecule with CNBr under non-reducing conditions generated five fragments, of which two major fragments (Mr 27,900 and 12,400) stained blue with Stains All, a reagent that stains sialic-acid-rich proteins/phosphate-containing proteins and/or Ca2+-binding proteins blue while staining other proteins pink. The 12,400-Mr fragment bound 45Ca2+ selectively, indicating a Ca2+-binding site in this part of the molecule. The 27,900-Mr fragment did not bind Ca2+, and since biosynthetic studies with 32PO4(3-) did not show phosphorylation of porcine osteonectin, this fragment is likely to be highly acidic. The incomplete cleavage of the molecule with CNBr and the ability of the molecule to regain its secondary structure after exposure to 7 M-urea are features consistent with the molecule having a compact structure that is stabilized by numerous disulphide bridges. The chemical and binding properties of porcine osteonectin are closely similar to the recently described ‘culture shock’, SPARC and BM-40 proteins, indicating that these are homologous proteins.

Change in phenotype in long-term cultures of a clonal rat bone cell line: switch to the synthesis of α1 (I)-trimer collagen

1984 ◽  
Vol 62 (6) ◽  
pp. 462-469 ◽  
Author(s):  
Hardy Limeback ◽  
Kichibee Otsuka ◽  
Kam-Ling Yao ◽  
Jane E. Aubin ◽  
Jaro Sodek
Keyword(s):  
Collagen Synthesis ◽  
Type I Collagen ◽  
Bone Cell ◽  
Detectable Effect ◽  
Prostaglandin E ◽  
Intracellular Camp ◽  
Type Iii Collagen ◽  
Type I ◽  
Type Iii ◽  
Type V

A number of bone cell clones isolated from rat calvaria have been maintained in culture for more than 3 years. Several of these clones have undergone dramatic changes in phenotype. One of these clones, RGB 2.2, was observed originally to have a fibroblastic morphology in culture and to respond to parathyroid hormone (PTH), but not prostaglandin E2 (PGE2), with an increase in intracellular cAMP. Throughout several passages in early subcultures, these cells synthesized mostly type I collagen, with small amounts of type III and type V collagens. Whereas PTH had no detectable effect on collagen synthesis, PGE2 decreased the amount of total cell layer collagen, with the greatest effect on type III collagen, while increasing the proportion of type V collagen. Subsequent studies on these cells during 3 years in culture have indicated changes in their phenotype including a progressive change in morphology to a more cuboidal shape and a change in collagen synthesis, the cells producing large amounts of the "embryonic" collagen, α1(I) trimer. The reason(s) for the change in collagen expression is unknown, but may be the result of a change in which gene(s) is being expressed.

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