Hydroxycamptothecin liposomes inhibit collagen secretion and induce fibroblast apoptosis in a postlaminectomy rabbit model

Pharmacotherapy for Keloids and Hypertrophic Scars

Keloids (KD) and hypertrophic scars (HTS), which are quite raised and pigmented and have increased vascularization and cellularity, are formed due to the impaired healing process of cutaneous injuries in some individuals having family history and genetic factors. These scars decrease the quality of life (QOL) of patients greatly, due to the pain, itching, contracture, cosmetic problems, and so on, depending on the location of the scars. Treatment/prevention that will satisfy patients' QOL is still under development. In this article, we review pharmacotherapy for treating KD and HTS, including the prevention of postsurgical recurrence (especially KD). Pharmacotherapy involves monotherapy using a single drug and combination pharmacotherapy using multiple drugs, where drugs are administered orally, topically and/or through intralesional injection. In addition, pharmacotherapy for KD/HTS is sometimes combined with surgical excision and/or with physical therapy such as cryotherapy, laser therapy, radiotherapy including brachytherapy, and silicone gel/sheeting. The results regarding the clinical effectiveness of each mono-pharmacotherapy for KD/HTS are not always consistent but rather scattered among researchers. Multimodal combination pharmacotherapy that targets multiple sites simultaneously is more effective than mono-pharmacotherapy. The literature was searched using PubMed, Google Scholar, and Online search engines.

Postoperative Epidural Fibrosis: Challenges and Opportunities - A Review

Postoperative epidural fibrosis (EF) is still a major limitation to the success of spine surgery. Fibrotic adhesions in the epidural space, initiated via local trauma and inflammation, can induce difficult-to-treat pain and constitute the main cause of failed back surgery syndrome, which not uncommonly requires operative revision. Manifold agents and methods have been tested for EF relief in order to mitigate this longstanding health burden and its socioeconomic consequences. Although several promising strategies could be identified, few have thus far overcome the high translational hurdle, and there has been little change in standard clinical practice. Nonetheless, notable research progress in the field has put new exciting avenues on the horizon. In this review, we outline the etiology and pathogenesis of EF, portray its clinical and surgical presentation, and critically appraise current efforts and novel approaches toward enhanced prevention and treatment.

Preparation and in vitro and in vivo evaluations of 10-hydroxycamptothecin liposomes modified with stearyl glycyrrhetinate

10-Hydroxycamptothecin (HCPT) liposomes surface modified with stearyl glycyrrhetinate (SG) were prepared by the film dispersion method. Characterization of the liposomes, including drug release in vitro, pharmacokinetics and tissue distribution, was done. HCPT in plasma and tissues was determined by high-performance liquid chromatography (HPLC). Compared with the conventional HCPT-liposomes and commercially available hydroxycamptothecin injection (HCPT Inject), pharmacokinetic parameters indicated that SG-HCPT-liposomes had better bioavailability. Regarding tissue distribution, the concentration of HCPT loaded by SG modified liposomes in the liver was higher than other tissues and the risk to the kidney was lower than HCPT-liposomes and HCPT Inject. These results support the hypothesis that the HCPT-liposomes modified with SG show enhanced liver-targeting through the glycyrrhetinic acid (GA) receptor to be an efficient drug carrier, which may help to improve therapeutic methods for hepatic diseases in the future.

Dynamic features of liver fibrogenesis and fibrosis resolution in the absence of matrix metalloproteinase‑9

The two‑edged effect of matrix metalloproteinase‑9 (MMP9) makes it difficult to understand its role in liver fibrogenesis and fibrosis resolution. The present study aimed to investigate the dynamic features of liver fibrogenesis and fibrosis resolution in the absence of MMP9. MMP9‑/‑ mice were used to induce liver fibrosis by thioacetamide. The degrees of liver fibrogenesis and fibrosis resolution were designated by the levels of collagen I, III and IV, which were determined via western blotting. Liver injury and the transcriptional levels of MMPs and tissue inhibitor of metalloproteinases (TIMPs) were also determined. It was revealed that, in the absence of MMP9, acute liver injury was attenuated and the expression of collagen was alleviated at the early stage of liver fibrosis, particularly in the first 3 weeks. However, their levels increased to levels as high as those in the control group by week 8. During liver fibrosis resolution, in the absence of MMP9, the ratio of (MMP9 + MMP13)/TIMP1 and the ratio of (MMP2+ MMP14)/TIMP2 were decreased, and the collagen levels were increased. The present study revealed the dynamic features of liver fibrogenesis and fibrosis resolution in the absence of MMP9. The information obtained here will improve current understanding of the effect that MMP9 has in liver fibrogenesis and fibrosis resolution.

The Effect of Hydroxycamptothecin on Wound Healing Following Reduction of the Knee Intra-Articular Adhesion in Rabbits

Topical application of 10-hydroxycamptothecin (HCPT) can reduce intra-articular scar adhesion after knee surgery, but the effect of HCPT on wound healing has not yet been elucidated. The study investigates the effect of the topical application of HCPT on wound healing after knee surgery in rabbits. Forty New Zealand white rabbits were divided into five groups: 2.0, 1.0, 0.5, and 0.1 mg/ml HCPT groups and control group. Approximately 10 mm × 10 mm of the cortical bone was removed from both sides of the femoral condyle, and the underneath of the cancellous bone was exposed. HCPT in various concentrations or saline was applied to the decorticated sites. Two weeks after surgery, the intra-articular adhesion was evaluated by Masson's trichrome staining. The blood vessel density and the fibroblast counting were evaluated by hematoxylin-eosin staining. The Vascular endothelial growth factor (VEGF) expression was evaluated by immunohistochemical staining and mRNA measurement. The recovery of all rabbits was stable after surgery. Topical application of HCPT could reduce intra-articular adhesion after 2 weeks. The blood vessel density, the number of fibroblast, and the level of VEGF expression in 2.0 and 1.0 mg/ml HCPT groups were lower than those of 0.5 mg/ml HCPT group, 0.1 mg/ml HCPT group, and the control group. However, there was no difference in multiple parameters between 1.0 and 2.0 mg/ml HCPT groups. Topical application of HCPT could reduce intra-articular scar adhesion in rabbits, but HCPT with concentrations above 1.0 mg/ml may affect the wound healing process by inhibiting the angiogenesis and fibroblast proliferation.

Phytantriol based liquid crystal provide sustained release of anticancer drug as a novel embolic agent

Phytantriol has received increasing amount of attention in drug delivery system, however, the ability of the phytantriol based liquid crystal as a novel embolic agent to provide a sustained release delivery system is yet to be comprehensively demonstrated. The purpose of this study was to prepare a phytantriol-based cubic phase precursor solution loaded with anticancer drug hydroxycamptothecine (HCPT) and evaluate its embolization properties, in vitro drug release and cytotoxicity. Phase behavior of the phytantriol-solvent-water system was investigated by visual inspection and polarized light microscopy, and no phase transition was observed in the presence of HCPT within the studied dose range. Water uptake by the phytantriol matrices was determined gravimetrically, suggesting that the swelling complied with the second order kinetics. In vitro evaluation of embolic efficacy indicated that the isotropic solution displayed a satisfactory embolization effect. In vitro drug release results showed a sustained-release up to 30 days and the release behavior was affected by the initial composition and drug loading. Moreover, the in vitro cytotoxicity and anticancer activity were evaluated by MTT assay. No appreciable mortality was observed for NIH 3T3 cells after 48 h exposure to blank formulations, and the anticancer activity of HCPT-loaded formulations to HepG2 and SMMC7721 cells was strongly dependent on the drug loading and treatment time. Taken together, these results indicate that phytantriol-based cubic phase embolic gelling solution is a promising potential carrier for HCPT delivery to achieve a sustained drug release by vascular embolization, and this technology may be potential for clinical applications.

Medicinal plants for the treatment of hypertrophic scars

Hypertrophic scar is a complication of wound healing and has a high recurrence rate which can lead to significant abnormity in aesthetics and functions. To date, no ideal treatment method has been established. Meanwhile, the underlying mechanism of hypertrophic scarring has not been clearly defined. Although a large amount of scientific research has been reported on the use of medicinal plants as a natural source of treatment for hypertrophic scarring, it is currently scattered across a wide range of publications. Therefore, a systematic summary and knowledge for future prospects are necessary to facilitate further medicinal plant research for their potential use as antihypertrophic scar agents. A bibliographic investigation was accomplished by focusing on medicinal plants which have been scientifically tested in vitro and/or in vivo and proved as potential agents for the treatment of hypertrophic scars. Although the chemical components and mechanisms of action of medicinal plants with antihypertrophic scarring potential have been investigated, many others remain unknown. More investigations and clinical trials are necessary to make use of these medical plants reasonably and phytotherapy is a promising therapeutic approach against hypertrophic scars.

The optimal concentration of topical hydroxycamptothecin in preventing intraarticular scar adhesion

10-Hydroxycamptothecin could reduce intraarticular adhesion by inhibiting fibroblasts proliferation after knee surgery. However, the ideal concentration of hydroxycamptothecin have not been defined. This study was tried to verify the optimal concentration of 10-hydroxycamptothecin in preventing knee intraarticular adhesion. Sixty rabbits were randomly divided into five groups. Approximately 10 mm × 10 mm of the cortical bone was removed from both sides of the femoral condyle and the underneath cancellous bone was exposed. Various concentrations of hydroxycamptothecin (0.1 mg/ml, 0.5 mg/ml, 1.0 mg/ml, 2.0 mg/ml) or saline were applied to the decorticated areas for 10 minutes. After four weeks, the degree of inraarticular adhesion was assessed by macroscopic evaluation, biochemical analysis of hydroxyproline content and histological evaluation. The results demonstrated that the extent of knee inraarticular adhesion in 1.0 mg/ml group and 2.0 mg/ml hydroxycamptothecin group were significantly lower than those of 0.5 mg/ml group, 0.1 mg/ml hydroxycamptothecin group and control group. Moreover, there was no significant difference between 1.0 mg/ml group and 2.0 mg/ml hydroxycamptothecin group. In conclusion, topical application of 1.0 mg/ml hydroxycamptothecin may be the optimal concentration in reducing intraarticular adhesion after knee surgery in rabbits.