The skin is the largest organ in the human body and is highly susceptible to physical injury such as surgeries, traumas, and burns (Coentro et al., 2019). To maintain life, the skin must heal quickly, involving a complex physiologic process where the body attempts to replace injured skin with newly generated tissue and restore its barrier functions (Mony et al., 2023). This process involves four stages: hemostasis, inflammation, proliferation, and remodeling, as well as communication between many different types of cells (Gurtner et al., 2008). Under normal conditions, these stages occur in a highly sequential and finite manner, and the myofibroblasts undergo apoptosis during the remodeling stage, leaving a relatively acellular scar at the healed sites (Bharadia et al., 2023). However, this process sometimes does not occur sequentially and finitely, resulting in aberrant wound-healing processes and subsequent fibroproliferative disorders and hypertrophic scars (HSs) (Gurtner et al., 2008; Limandjaja et al., 2021). HSs are characterized by excessive extracellular matrix (ECM), especially collagen, deposition during the wound healing process, leading to raised, often red, thickened scars that remain within the boundaries of the original wound (Diegelmann and Evans, 2004; Lingzh et al., 2020). These scars can be painful and itchy, symptoms that may worsen with elevated ambient temperature, emotional arousal, or consumption of spicy foods (Bharadia et al., 2023; Jeschke et al., 2023), affecting 30%–90% of patients with wounds (Bharadia et al., 2023; Limandjaja et al., 2021) and posing serious social, functional, and economic burdens due to their appearance, contractures, and the costs associated with scar treatment (Thombs et al., 2008; Leblebici et al., 2006; Mcphail et al., 2022). Considering the significant portion of the population suffering from HSs, effectively preventing the formation of HSs during wound healing or removing already formed HSs is of great importance.

Currently, there are two mature clinical measures for preventing and treating the formation of HSs. The first is known as first-line therapy, represented by silicone gel sheeting (Bharadia et al., 2023). For example, silicone gel has been reported to reduce the expression of transforming growth factor (TGF)-β1, platelet-derived growth factor, and basic fibroblast growth factor (b-FGF) 4 months after surgery for surgical scars (Choi et al., 2015). However, other studies have reported that silicone gel can also upregulate the expression of b-FGF in the dermis of silicone gel sheet-treated scars (O’brien and Jones, 2013). The second measure is known as second-line therapy, which includes laser therapy as well as surgical excision in combination with intralesional corticosteroid injections postoperatively (Bharadia et al., 2023; Atiyeh, 2020). For instance, it has been reported that long-pulsed Nd:YAG laser and pulsed dye can lighten the color, reduce the thickness and tension of HSs, and relieve symptoms such as pain and pruritus (Amini-Nik et al., 2018).

In recent years, traditional Chinese medicine (TCM), including various extracts, has been proven effective as a potential therapy for treating HSs due to its roles in promoting skin regeneration and resisting skin aging. For example, many traditional plant-based products, such as quercetin, onion extract, resveratrol, epigallocatechin gallate, oleanolic acid, and curcumin, have been used clinically, providing relief to patients to varying extents (Bharadia et al., 2023). Scar healing ointment (SHO) is a TCM prescription for the external treatment of scarring. It includes ingredients like Wubeizi (Galla Chinensis), Wumei (Mume Fructus), Baizhi (Angelicae Dahuricae), Shechuangzi (Fructus Cnidii), Qianliguang (Senecio Scandens), and Digupi (Cortex Lycii), and has been clinically effective in preventing the formation of HSs and removing already formed HSs. However, the underlying mechanisms of its effects on HS prevention and treatment remain unclear.

Network pharmacology is a promising approach to reveal the pharmacological mechanisms of Chinese medicine formulas (Zhao et al., 2023) and predict their potential targets for specific diseases (Zhang et al., 2017; Kou and Ma, 2024). Molecular docking is a significant method in structural molecular biology and computer-aided drug design (Saikia and Bordoloi, 2019). Therefore, in the present study, we aim to analyze the active ingredients and molecular targets of SHO using network pharmacology and molecular docking methods to explore its potential underlying mechanisms for the prevention and treatment of HSs. Our study will provide new drug and target options for the prevention and treatment of HSs, and offer theoretical support for further research and promotion of SHO.

HSs are a condition with complex mechanisms that impose significant economic and psychological burdens on patients with wounds (Mony et al., 2023; Bharadia et al., 2023; Mcphail et al., 2022). Recently, various extracts from multiple TCM have been reported to show effects in preventing and treating HSs (Ning et al., 2021; Chen et al., 2022). SHO is a TCM prescription used for the external treatment of scarring, showing potential effects in treating HSs. However, the underlying mechanisms of SHO’s effects on HSs remain unexplored. In this study, using bioinformatic methods, we systematically explored the potential mechanisms of SHO in the treatment of HSs.

The SHO formula, developed from decades of clinical experience, has been used for external treatment of scaring since the 1960s, successfully treating thousands of patients with HSs. The SHO formula includes Galla Chinensis, Fructus Mume, Radix Angelicae Dahuricae, Fructus Cnidii, Herba Senecionis Scandentis, and Cortex Lycii. Based on the TCM theory of “qi and blood stasis, and toxic accumulation”, it follows the principle of “softening hardness, dissipating nodules, and detoxifying”. Galla Chinensis, the principal herb, has astringent, toxic-expelling, and hardness-softening properties, helping to reduce swelling and scar formation. Modern pharmacology shows it has powerful antioxidant properties, protecting biological macromolecules from damage (Ren et al., 2021). Fructus Mume, sour and astringent, complements Galla Chinensis by reducing scars (Zhang et al., 2023). Radix Angelicae Dahuricae promotes blood circulation, dissipates blood stasis, reduces swelling, and generates new tissue. Fructus Cnidii clears heat, dries dampness, dispels wind, and relieves itching. Herba Senecionis Scandentis clears heat, detoxifies, kills parasites, and relieves itching. Together, these herbs have antibacterial and anti-inflammatory effects, theoretically capable of controlling local inflammation, reducing pain and itching, and accelerating wound healing, thereby shortening the treatment duration.

We first retrieved the active ingredients in the SHO formula from the TCMSP database, and HSs-related target genes from five databases. Since there was no information about Senecio Scandens in the TCMSP database, we obtained its active ingredients from the HERB database. To ensure the rigor of our analyses, we cross-validated these active ingredients with the TCMSP database and used only those certified by the TCMSP database in our subsequent analyses. After a series of analyses, we identified 57 active ingredients and predicted 42 potential targets in the six herbs pf SHO (Table 1; Figure 1). Notably, since SHO is an external ointment, dermal permeability parameters should ideally be used as screening criteria. However, due to the limited number of network pharmacology studies focused on external drug applications, most databases do not provide dermal permeability parameters for active ingredients, and such data are generally unavailable. Consequently, this study employed pharmacokinetic parameters commonly used in other network pharmacology studies (Fan et al., 2024; Han et al., 2022) as the screening criteria. This limitation may affect the reliability of our findings and highlights the importance of incorporating dermal permeability parameters in future research. Network analyses indicated that SHO might affect HSs by regulating proteins such as AKT1, MAPK1, CCND1, TP53, GSK3B, BCL2, CDKN1A, ESR1, and MYC (Figure 3). GO and KEFF enrichment analyses showed that these targets are involved in multiple categories and pathways, such as the cytokine activity, regulation of apoptotic signaling pathway, response to oxidative stress, response to a steroid hormone, et al. (Supplementary Table S6; Supplementary Table S7), all of which are considered mechanisms of HSs (Mony et al., 2023; Gurtner et al., 2008; Diegelmann and Evans, 2004). Considering that SHO is used for external treatment, it is likely to act by influencing the response of myofibroblasts to regulatory factors in the microenvironment, such as cytokines and reactive oxygen species.

To further investigate the underlying molecular mechanisms, we performed molecular docking analyses of these hub target proteins and the core active ingredients in the SHO formula (Figure 2; Table 2). Although we identified three complexes with high affinities (Figure 5A), one of them did not form hydrogen bonds (Figure 5B), indicating that this conformation is unstable. The remaining two conformations, the MAPK1-stigmasterol complex, and the ESR1-alloimperatorin complex, showed high affinities and formed hydrogen bonds (Figures 5C,D), suggesting they are the most likely underlying molecular mechanisms of SHO’s effects on HSs. It should be noted that our docking results only offer preliminary indications of potential interactions. To more accurately assess binding stability, further validation through molecular dynamics simulations and binding free energy calculations is required.

Indeed, inhibition of the TGF-β1-ERK/JNK pathway has previously been found to be involved in scar formation. For example, basic fibroblast growth factor stimulates the proliferation of human dermal fibroblasts via the ERK1/2 and JNK pathways (Makino et al., 2010), and loureirin B has been found to inhibit the formation of HSs by inhibiting the TGF-β1-ERK/JNK pathway (He et al., 2015). Additionally, ESR1 is also identified to play important roles in skin aging and wound healing process (Saville and Hardman, 2014; Smith, 2017). These findings suggest that the mechanisms by which SHOW treats HSs may involve the regulation of ERK2 and ESR1 proteins. However, it is important to note that molecular docking results alone do not provide definitive evidence of molecular interactions. To address this limitation, binding assays should be conducted in wet-lab experiments to confirm these interactions, and further validation of the underlying mechanisms is warranted through both in vivo and in vitro studies.

In summary, this study analyzed the effective targets and action pathways of the SHO formula and preliminarily explored its molecular mechanisms in treating HSs using network pharmacology and molecular docking methods. Our findings revealed that the main active ingredients of SHO include quercetin, beta-sitosterol, kaempferol, stigmasterol, luteolin, alloimperatorin, acacetin, and (E)-2,3-bis(7-methoxy-2-oxochromen-8-yl)prop-2-enal. The hub target proteins identified were AKT1, MAPK1, CCND1, TP53, GSK3B, BCL2, CDKN1A, ESR1, and MYC. GO and KEGG enrichment analyses indicated that these hub target genes are involved in processes and pathways related to apoptosis and responses to oxidants. Molecular docking analysis identified the MAPK1-stigmasterol and ESR1-alloimperatorin complexes as having high affinities and forming hydrogen bonds, suggesting that the SHO formula may affect the MAPK1 and ESR1 proteins, thereby preventing and treating HSs. Our study will provide new drug and target options for the prevention and treatment of HSs, and offer theoretical support for further research and promotion of SHO. However, further in vivo and in vitro studies are warranted to validate these mechanisms.