Development of polyurethane foam dressing containing silver and asiaticoside for healing of dermal wound

 Polyurethane foam dressings for dermal wounds were formulated with natural polyols in order to improve the foam characteristics and the release of 2 active agents, silver and asiaticoside (AS) as an antimicrobial agent and an herbal wound healing agent, respectively. The foam was instantly formed by interaction of polyols and diisocyanate. Hydroxypropyl methylcellulose, chitosan and sodium alginate were individually mixed with the main polyols, polypropylene glycol, in the formulation while the active components were impregnated into the obtained foam dressing sheets. Although the type and amount of the natural polyols slightly affected the pore size, water sorption-desorption profile and compression strength of the obtained foam sheets, a prominent effect was found in the release of both active components. Among natural polyols formulations, foam sheets with alginate showed the highest silver and AS release. Non-cytotoxicity of these foam sheets to human fibroblast cells was confirmed. Antimicrobial testing on four bacteria strains showed that 1 mg/cm2 silver in formulations with 6% of natural polyols and without natural polyols had sufficient content of the silver release with comparable inhibition zone and significantly larger zone than other formulations. In pig study, the foam dressing with 6% alginate, 1 mg/cm2 silver and 5% AS could improve wound healing in both the percentage of the wound closure and histological parameters of the dermal wound without any dermatologic reactions. In conclusion, this innovative foam dressing had potential to be a good candidate for wound treatment.     

积雪苷在妇科腹腔镜术后患者促进伤口愈合应用中的效果观察

目的观察积雪苷霜软膏促进妇科腹腔镜手术后患者伤口愈合,减少瘢痕形成,提高患者形象自我满意度的效果。方法随机选取妇科腹腔镜手术后100例患者分成两组,实验组患者给予指导应用积雪苷霜软膏,对照组患者未予应用积雪苷软膏,伤口自然愈合。观察患者术后4周伤口愈合时间,创面色素沉着及患者对创面外观自身感受主观评价的差别。结果应用积雪苷霜软膏患者伤口愈合时间短,色素沉着发生率小,患者对创面外观自我满意度高。结论积雪苷霜软膏可以有效促进伤口愈合,减少瘢痕形成及色素沉着,能够满足女性患者对腹部创面外观的要求,有效减轻对术后自我形象的心理顾虑。     

正交试验优化积雪草总苷提取工艺

目的:优化积雪草中积雪草总苷的提取工艺。方法:以积雪草总苷提取率为评价指标,采用单因素试验与正交试验优选积雪草中积雪草总苷的提取条件。结果:积雪草总苷的最优提取工艺为乙醇浓度60%,料液比1:12,超声提取1h。结论:该提取方法简单可行,可使积雪草总苷提取率较高。     

羟基积雪草苷与积雪草苷对LPS诱导大鼠发热模型的影响

目的观察积雪草苷和羟基积雪草苷的解热作用,并比较两者在解热作用上的差异。方法将80只SD大鼠随机分为空白组、模型组(LPS 100μg/kg)、溶酶对照组(羧甲基纤维素钠)、积雪草苷5,15,45 mg/kg、羟基积雪草苷10,20,40mg/kg、对乙酰氨基酚50 mg/kg组。腹腔注射LPS(100μg/kg)建立SD大鼠发热模型,绘制各组平均体温变化曲线,比较测量体温与基础体温差值ΔT。结果羟基积雪草苷(10,20,40 mg/kg)与积雪草苷(5,15,45 mg/kg)对LPS诱导的SD大鼠发热模型体温有显著的降温作用(P<0.05)。结论羟基积雪草苷和积雪草苷对LPS诱导的SD大鼠发热模型的体温均有降温作用,积雪草苷在某些时间点(如LPS注射5 h后)降温效应优于羟基积雪草苷。     

Protective effects of asiaticoside on septic lung injury in mice

Asiaticoside (AS), a major triterpenoid saponin component isolated from Centella asiatica, has been described to exhibit antioxidant and anti-inflammatory activities. The present study aimed to determine the protective effects and the underlying mechanisms of AS on septic lung injury induced by cecal ligation and puncture (CLP). Mice were pretreated with the AS (45 mg/kg) or AS as well as GW9662 at 1 h before CLP, the survival, lung injury, inflammatory mediators and signaling molecules, and Peroxisome proliferator-activated receptor-γ (PPAR-γ) were determined 24 h after CLP. The results showed that AS significantly decreased CLP-induced the mortality, lung pathological damage, the infiltration of mononuclear, polymorphonuclear (PMN) leucocytes and total proteins. Moreover, AS inhibited CLP-induced the activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB), the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) protein in lung tissues, and the production of serum tumor necrosis factor (TNF-α) and interleukin-6 (IL-6). Interestingly, the expression of PPAR-γ protein in lung tissue was up-regulated by AS. Furthermore, GW9662 (the inhibitor of PPAR-γ) significantly reversed these beneficial effects of AS in septic mice. These findings suggest that AS could effectively protect from septic lung injury induced by CLP and the underlying mechanisms might be related to up-regulation of PPAR-γ expression to some extent, which inhibits MAPKs and NF-κB pathway.     

Advanced formulation and pharmacological activity of hydrogel of the titrated extract ofC. asiatics

Titrated extract of Centella asiatica (TECA) contains three principal ingredients, asiaticoside (AS), asiatic acid (AA), and madecassic acid (MA). These components are known to be clinically effective on systemic scleroderma, abnormal scar formation, and keloids. However, one problem associated with administration of TECA is its low solubility in aqueous as well as oil medium. In this study, various nonionic surfactants and bile salts as anionic surfactant were tested and screened for solubilizing TECA with a view to developing topical hydrogel type of ointment which is stable physicochemically, and has better pharmacological effects. When TECA was incorporated into various nonionic surfactant systems, labrasol had the most potent capacity for solubilizing TECA. In cases of bile salt systems, Na-deoxycholate (Na-DOC) had foremost solubilizing capacity, even more than labrasol. In differential scanning calorimetric study, the peaks of AA, MA, AS and Na-DOC disappeared at the coprecipitate of 1% TECA and 1% Na-DOC, suggesting the optimum condition of Na-DOC for solubilizing TECA. When the physicochemical stability of hydrogel containing this mixture was assessed, it was stable at room temperature for at least one month. Pharmacologically it significantly decreased the size of wound area at the 9th day when applied to the wound area of rat dorsal skin. Taken together, solubility of TECA was dramatically improved by using nonionic and anionic surfactant systems, and Na-DOC was found to be the most effective solubilizer of TECA in formulating a TECA-containing hydrogel typed ointment. Moreover this gel was considered to be applicable to clinical use for wound healing effect.     

薄层扫描法测定积雪苷片中积雪草苷的含量

目的：采用薄层扫描法测定积雪苷片中积雪草苷含量。方法：样品经适当提取后点于硅胶G薄层板上，以三氯甲烷-甲醇-水（65：35：10）下层溶液为展开剂，10％硫酸乙醇为显色剂，检测波长为γS=530nm，参比波长为γR=400nm。结果：平均加样回收率为100．7％，RSD=3．2％。结论：此方法简便、灵敏、准确，可用于该制剂的质量控制。     

Anxiolytic effects of standardized extract of Centella asiatica (ECa 233) after chronic immobilization stress in mice

Ethnopharmacological relevance

Centella asiatica has long been used for various neurological disturbances in Southeast Asian countries. The present study aims to demonstrate the anxiolytic effect of ECa 233, a standardized extract of C. asiatica containing triterpenoids not less than 80%, in comparison to diazepam.

Materials and methods

The test compound was given orally to non-stressed mice and mice subjected to chronic immobilization stress. Anxiolytic effect was assessed by an elevated plus maze (EPM), a dark-light box and an open-field tests.

Results

Anxiolytic effect of ECa 233 was clearly demonstrated in non-stressed mice subjected to acute stress in all behavioral tests employed. In the EPM test, chronically stressed mice showed significant decrease in the number of open arm entries, shortening the time spent in open arms and an increase of the latency to leave the central area, suggesting their release from the stress. In addition, ameliorating effect of ECa 233 was observed on the body weight and serum corticosterone which were adversely affected by immobilization stress. Madecassoside and asiaticoside, equal to their respective contents of the effective doses of ECa 233, exclusively presented anxiolytic effects in EPM, while no distinct effect was observed on the body weight and serum corticosterone.

Conclusions

The present study demonstrated anxiolytic effect of ECa 233 in both acutely and chronically stressed animals. These effects could be mainly accounted by madecassoside and asiaticoside, suggesting a possible use of ECa 233 for the treatment of both acute and chronic anxiety in the pathological state.