Traditional Chinese medicine for hypertrophic scars—A review of the therapeutic methods and potential effects

A strategy for selective screening of dual-target bioactive compounds against hypertrophic scar through inhibiting angiotensin II type 1 receptor while stimulating type 2 receptor from Chinese herbs

BACKGROUND

Cutaneous hypertrophic scar is a fibro-proliferative hard-curing disease. Recent studies have proved that antagonists of angiotensin II type 1 receptor (AT1R) and agonists of type 2 receptor (AT2R) were able to relieve hypertrophic scar. Therefore, establishing new methods to pursue dual-target lead compounds from Chinese herbs is in much demand for treating scar.

METHODS

To this end, we immobilized AT1R or AT2R onto the surface of silica gel from cell lysates through a specific covalent bond by bioorthogonal chemistry. The columns containing immobilized AT1R or AT2R were jointly utilized to pursue potential bioactive compounds simultaneously binding to AT1R and AT2R from the extract of Rhei Radix et Rhizoma. Their functions on AT1R and AT2R expressions were investigated by in vitro and in vivo experiments.

RESULTS

Aloe-emodin and emodin were identified as the potential bioactive compounds binding to both of the two receptors, thereby improving the appearance and pathomorphology of hypertrophic scar. They blocked the AT1R pathway to down-regulate the expression of transforming growth factor-β1 (TGF-β1) and stimulate matrix metalloproteinase-1 (MMP-1) expression. As such, the expression of collagen I/III reduced. Conversely, the bindings of the two compounds to AT2R reduced the production of nuclear factor-кB1 (NF-кB1), whereby the generation of interleukin-6 (IL-6) was blocked.

CONCLUSION

We reasoned that aloe-emodin and emodin had the potential to become dual-target candidates against hypertrophic scar through the regulation of AT1R and AT2R signaling pathways. It showed considerable potential to become a universal strategy for pursuing multi-target bioactive compounds from Chinese herbs by the utilization of diverse immobilized receptors in a desired order.

Leveraging Microneedles for Raised Scar Management

Disruption of the molecular pathways during physiological wound healing can lead to raised scar formation, characterized by rigid, thick scar tissue with associated symptoms of pain and pruritus. A key mechanical factor in raised scar development is excessive tension at the wound site. Recently, microneedles (MNs) have emerged as promising tools for scar management as they engage with scar tissue and provide them with mechanical off-loading from both internal and external sources. This review explores the mechanisms by which physical intervention of drug-free MNs alleviates mechanical tension on fibroblasts within scar tissue, thereby promoting tissue remodeling and reducing scar severity. Additionally, the role of MNs as an efficient cargo delivery system for the controlled and sustained release of a wide range of therapeutic agents into scar tissue is highlighted. By penetrating scar tissue, MNs facilitate controlled and sustained localized drug administration to modulate inflammation and fibroblastic cell growth. Finally, the remaining challenges and the future perspective of the field have been highlighted.

Preparation of Compound Salvia miltiorrhiza-Blumea balsamifera Nanoemulsion Gel and Its Effect on Hypertrophic Scars in the Rabbit Ear Model

Hypertrophic scars (HS) still remain an urgent challenge in the medical community. Traditional Chinese medicine (TCM) has unique advantages in the treatment of HS. However, due to the natural barrier of the skin, it is difficult for the natural active components of TCM to more effectively penetrate the skin and exert therapeutic effects. Therefore, the development of an efficient drug delivery system to facilitate enhanced transdermal absorption of TCM becomes imperative for its clinical application. In this study, we designed a compound Salvia miltiorrhiza-Blumea balsamifera nanoemulsion gel (CSB-NEG) and investigated its therapeutic effects on rabbit HS models. The prescription of CSB-NEG was optimized by single-factor, pseudoternary phase diagram, and central composite design experiments. The results showed that the average particle size and PDI of the optimized CSB-NE were 46.0 ± 0.2 nm and 0.222 ± 0.004, respectively, and the encapsulation efficiency of total phenolic acid was 93.37 ± 2.56%. CSB-NEG demonstrated excellent stability and skin permeation in vitro and displayed a significantly enhanced ability to inhibit scar formation compared to the CSB physical mixture in vivo. After 3 weeks of CSB-NEG treatment, the scar appeared to be flat, pink, and flexible. Furthermore, this treatment also resulted in a decrease in the levels of the collagen I/III ratio and TGF-β1 and Smad2 proteins while simultaneously promoting the growth and remodeling of microvessels. These findings suggest that CSB-NEG has the potential to effectively address the barrier properties of the skin and provide therapeutic benefits for HS, offering a new perspective for the prevention and treatment of HS.

Pharmacological Significance of Boraginaceae with Special Insights into Shikonin and Its Potential in the Food Industry

Shikonin is a naphthoquinone pigment present in the hairy roots of the plant species from the Boraginaceae family. The compound has been well investigated for its highly efficient medicinal, antioxidant, and antimicrobial properties. Various extraction methodologies have been employed to maximise yield while minimising waste production of shikonin and its derivatives. Despite substantial research on shikonin and Boraginaceae plants, a research gap persists in the food industry and extraction technologies. This review addresses crucial aspects of shikonin deserving of further exploration. It begins by elucidating the attributes of the Boraginaceae plants and their medicinal traits in folklore. It proceeds to focus on the roots of the plant and its medicinal properties, followed by extraction procedures explored in the last fifteen years, emphasising the novel technologies that have been chosen to improve the yield extract while minimising extraction times. Furthermore, this review briefly outlines studies employing cell culture techniques to enhance in vitro shikonin production. Lastly, attention is directed towards research in the food industry, particularly on shikonin-loaded biodegradable films and the antioxidant activity of shikonin. This review concludes by summarising the future potential in food science and prominent research gaps in this field.

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.

The mechanism of Semen Persicae-Flos Carthami in treating hypertrophic scar: A study based on network pharmacological analysis and in vitro experiments

Traditional medicine believes that hypertrophic scar (HS) falls into the category of "blood stasis". Chinese herbs for promoting blood circulation and removing blood stasis, activating meridians, and relieving pain are usually selected to treat HS by traditional Chinese medicine (TCM). Both Semen Persicae (SP) and Flos Carthami (FC) are confirmed to be effective for HS. Clinically, SP and FC are often used in combination with each other. However, the pharmacodynamic mechanism and molecular target of SP-FC in the treatment of HS are still unclear. Therefore, this study is intended to explore the mechanism and target of SP-FC in the treatment of HS through network pharmacology combined with in vitro cell and molecular biology experiments. Target genes of SP-FC were obtained from the traditional Chinese medicine systems pharmacology database and analysis platform (TCMSP), and targets of HS-related diseases were searched from databases such as Disgenet and GeneCards. Based on the targets searched and obtained, a Venn diagram was plotted to acquire common targets of SP-FC-HS. Next, STRING 11.0 was employed for protein-protein interaction (PPI) network analysis of common targets; and cytoscape 3.9.0 for connection relationship analysis of PPI and plotting of a "drug-component-target" network diagram. Besides, a modified explant culture method was applied to separate primary hypertrophic scar fibroblasts (HSFs); MTT assay to detect cell viability of HSFs after treatment by SP-FC for 24 h; Annexin V-FITC/PI double staining combined with flow cytometry to test apoptosis; western blot to check the protein expression level of p53; and real-time fluorescence quantitative PCR to determine mRNA level of p53. In the analysis of network pharmacology, 269 pharmacological targets of SP, 449 pharmacological targets of FC, and 2569 targets of HS-related diseases were screened from the databases. After plotting the Venn diagram, 116 common targets of SP-FC-HS were acquired. In vitro experiments showed that the expression of p53 in HSFs was decreased. SP-FC significantly reduces the viability of HSFs, increases p53 levels in HSFs, and promotes apoptosis. SP-FC can reduce scar formation by promoting p53 expression.

Centella triterpenes cream as a potential drug for the treatment of hypertrophic scar through inhibiting the phosphorylation of STAT3: A network pharmacology analysis and in vitro experiments

BACKGROUND

Hypertrophic scars (HS) often affect the normal function and appearance of the skin and bring adverse effects to the body and mind of patients, being a challenge in the fields of burns and plastic surgery as well as rehabilitation. Despite significant efficacy of centella triterpenes cream for treating HS clinically, its pharmacodynamics and molecular targets are still unclear. Therefore, the network pharmacology analysis combined with in vitro cell molecular biology experiments was used to explore the mechanism and targets of centella triterpenes cream treating HS in this study.

METHODS

First, target genes of asiaticoside (AC) were obtained from the databases including the Comparative Toxicogenomics Database, similarity ensemble approach, SwissTargetPrediction and TargetNet, and HS targets were acquired from the databases like Disgenet, GeneCards, and Online Mendelian Inheritance in Man. The common targets of AC-HS were obtained through plotting a Venn diagram. Subsequently, STRING 11.0 was employed for analyzing the protein-protein interaction (PPI) network of the common targets, and cytoscape 3.9.0 for analyzing the connectivity of PPI and plotting the network diagram of "drug-component-target". Additionally, a modified tissue culture method was applied to separate primary normal fibroblasts (NFs) in human skin and hypertrophic scar fibroblasts (HSFs). HSFs after 24-h AC treatment were subjected to MTT assay to detect cell viability, scratch assay to assess cell migration ability, and western blot to test the protein expression levels of STAT3, p-STAT3, transforming growth factor-β1 (TGF-β1), collagen I (COL 1), fibronectin 1 (FN1), and alpha-smooth muscle actin (α-SMA).

RESULTS

In network pharmacology analysis, 134 pharmacodynamic targets of AC and 2333 HS targets were obtained after retrieving the database, 50 AC-HS common targets were obtained by a Venn diagram, and a total of 178 edges and 13 core genes such as JUN and STAT3 were acquired by PPI analysis. In vitro experiments showed that the phosphorylation level of STAT3 (p-STAT3) was increased in HSFs. In addition to reducing p-STAT3 in HSFs, AC significantly inhibited the cell viability and migration of HSFs and downregulated the protein levels of TGF-β1, COL 1, FN 1, and α-SMA.

CONCLUSION

STAT3 can be activated in HS. AC may exert its pharmacological effects of inhibiting TGF-β1 signal transduction and regulating extracellular matrix remodeling in HS by inhibiting STAT3 phosphorylation. However, the specific molecular mechanism of AC remains to be verified through further experiments.

Gallic Acid Treats Hypertrophic Scar in Rabbit Ears via the TGF-β/Smad and TRPC3 Signaling Pathways

Hypertrophic scars (HSs) develop due to excessive collagen deposition and abnormal fibroblast proliferation during wound healing, significantly impacting patient quality of life. Three dosages of GA ointments were administered to rabbit ear HS models to investigate the potential efficacy and mechanism of gallic acid (GA) on HS. Daily application of ointment was performed on the matrix group, the GA ointment groups, and the silicone gel group for 28 days. (No drug treatment was performed on the skin and model groups as a blank group and vehicle group, and silicone gel ointment was topically administered to the silicone gel group as a positive control group.) Scar specimens were collected for histopathology analysis, RNA sequencing analysis, real-time quantitative polymerase chain reaction, and Western blot analysis at the first, second, and fourth weeks after the treatment. Low-dose and medium-dose GA effectively suppressed HS formation and markedly decreased fibroblast infiltration levels and scar thickness. Moreover, decreased expression of TRPC3 mRNA and TGF-β1, p-Smad2/3, and Smad2/3 protein was observed in the low- and medium-dose GA groups and the silicone gel group. This study provides evidence for the efficacy of GA in treating HS and sheds light on its potential underlying pharmacological mechanisms.

Exploring the Potential of Hesperidin in Preventing Hypertrophic Scars: Insights from a Rabbit Ear Model

Background

Hypertrophic scars, commonly occurring after trauma or surgery in critical areas like the head and joints, pose significant challenges to both physical and mental health due to their impact on skin function and aesthetics. While the complex pathogenesis involves fibroblast activation and collagen deposition, effective treatments are lacking, underscoring the importance of exploring pathogenesis and targeted therapies. Hesperidin, a bioactive compound in citrus fruits with diverse health benefits, including anti-fibrotic and anti-angiogenic effects, is the focus of this study with the aim of investigating its impact on hypertrophic scar formation, given its potential to promote blood flow and improve skin microcirculation.

Objective

This study aimed to observe the inhibitory effect of topical hesperidin on hypertrophic scars in rabbits.

Methods

A total of 8 healthy adult New Zealand white rabbits were used to establish a rabbit hypertrophic scarring animal model. Five wounds were created on each rabbit's two ears, with three wounds on the left ear (groups A, B, and C) and two wounds on the right ear (groups D and E). After six days of wound drying postoperatively, the wounds were locally treated with medication as followed: group A, 0.1% hesperidin; group B, 1% hesperidin; group C, 1% triamcinolone acetonide; group D, Vaseline; and group E, blank control without any medication. After 28 days, the scar tissue samples were collected for histological examination.

Results

The results showed that the scar texture of groups B and C was softer and lighter in color, and the number of fibroblasts, capillaries, and inflammatory cells in the tissue was significantly less than those in the other three groups. The hypertrophic scar indices of groups B and C were significantly smaller than those of groups A, D, and E, and the difference was statistically significant (P < 0.05). There were no significant difference between groups B and C.

Conclusion

Topical application of hesperidin demonstrated promising potential for reducing hypertrophic scar formation in rabbits.

Dispelling Dampness, Relieving Turbidity and Dredging Collaterals Decoction, Attenuates Potassium Oxonate-Induced Hyperuricemia in Rat Models

Purpose

Dispelling dampness, relieving turbidity and dredging collaterals decoction (DED), is a traditional Chinese medicine used in the treatment of hyperuricemia. We aimed to explore the effect and mechanism of DED in the treatment of hyperuricemia.

Methods

The effects of DED (9.48, 4.74, and 2.37 g/kg/d) on potassium oxonate (750 mg/kg/d)-induced hyperuricemia in rats were evaluated by serum uric acid (UA), creatinine (CRE), blood urea nitrogen (BUN), and renal pathological changes. Network pharmacology was used to identify the effective components and targets of DED, and the key targets and signaling pathways for its effects on hyperuricemia were screened. Molecular docking was used to predict the action of DED. H&E, immunohistochemistry, WB, and PCR were used to validate the network pharmacology results.

Results

DED can effectively alleviate hyperuricemia, inhibit UA, CRE, BUN, and xanthine oxidase (XOD) activity, and reduce renal inflammatory cell infiltration and glomerular atrophy. The experiment identified 27 potential targets of DED for hyperuricemia, involving 9 components: wogonin, stigmasterol 3-O-beta-D-glucopyranoside, 3β-acetoxyatractylone, beta-sitosterol, stigmasterol, diosgenin, naringenin, astilbin, and quercetin. DED can relieve hyperuricemia mainly by inhibiting RAGE, HMGB1, IL17R, and phospho-TAK1, and by regulating the AGE-RAGE and IL-17 signaling pathways.

Conclusion

DED can alleviate hyperuricemia by inhibiting XOD activity and suppressing renal cell apoptosis and inflammation via the AGE-RAGE signaling pathway and IL-17 signaling pathway. This study provides a theoretical basis for the clinical application of DED.