Therapeutic Effects of Acorus calamus L. Extract on Radiation-induced Skin Injury in a Rat Model

Summary

Radiation-induced skin injury is a common and severe complication of radiotherapy for cancer patients. There is no effective clinical treatment. This protocol evaluates the therapeutic effect of Acorus calamus L. extract on radiation-induced skin injury, aiming to provide new drug candidates and therapeutic strategies for its clinical prevention and treatment.

Abstract

Radiation-induced skin injury is a common and debilitating complication in cancer therapy, often resulting in delayed wound healing and increased patient discomfort. There are a few therapeutic drugs available for prevention or treatment. Traditional Chinese Medicine, specifically Acorus calamus L., has shown potential in treating various skin disorders, but its efficacy in radiation-induced skin injury remains underexplored.

This study used a Sprague-Dawley rat model exposed to 45 Gy radiation to induce skin injury. Rats were treated with 10%, 20%, and 40% Acorus calamus L. extract for 45 days. Wound healing, inflammation, apoptosis, and angiogenesis were assessed using wound healing rates, histopathological analysis, cytokine measurements, TUNEL staining, and immunohistochemistry. Treatment with Acorus calamus L. accelerated wound healing, with the medium-dose group showing the highest healing rate (88.97% at 45 days). Histopathological analysis revealed reduced inflammation, improved collagen organization, and new blood vessel formation. Serum levels of inflammatory cytokines (IL-1β, IL-6, TNF-α) were significantly reduced, and apoptosis was decreased, with modulation of key apoptotic proteins (P53, Bax, Bcl-2). VEGF and bFGF expression were upregulated, promoting angiogenesis and tissue repair. Acorus calamus L. enhances the healing of radiation-induced skin injuries by reducing inflammation, inhibiting apoptosis, and promoting angiogenesis. These findings suggest its potential as a therapeutic agent for managing radiation-induced skin damage, providing a promising alternative for managing radiation-induced skin injuries in clinical oncology. Further studies are needed to clarify its molecular mechanisms.

Introduction

Radiation-induced skin injury is a frequent and difficult complication of both nuclear accidents and tumor radiotherapy¹. In radiotherapy, about 95% of patients develop some degree of skin damage, including erythema, desquamation, recurrent necrotic ulcers, persistent pain, and an elevated risk of malignant progression². These lesions are often refractory to treatment, substantially reducing patients' quality of life and sometimes necessitating interruption of radiotherapy, thus posing a major clinical challenge in radiation oncology³. The underlying mechanisms of radiation-induced skin damage....

Protocol

The animal experiments described in this study were approved by the Animal Medical Research Ethics Committee of the Northern Theater Command General Hospital (Ethics Approval Number: 2018-03). SPF-grade male SD rats（6-8 weeks, weight 190-220 g）were used for the study. The details of the reagents and equipment used are listed in the Table of Materials.

1. Housing the experimental animals

1. Select 108 SPF male SD rats, aged between 6 to 8 weeks and weighing between 190 to 220 g.
2. Maintain the animal room temperature at 22 ± 2 °C, relative humidity at 50 ± 5%, an....

Results

Therapeutic effect of Acorus calamus L. on radiation-induced skin injury
15 days post-irradiation, all groups of rats exhibited dry peeling, localized redness, swelling, ulceration, and scabbing. At 30 days post-irradiation, the model group showed the most severe skin damage, with scabbing and ulceration at the irradiated site reaching their peak. At 45 days, the model group showed minimal scab shedding, and the wound exhibited some contraction. In contrast, the Acorus calamus L. and positive drug-.......

Discussion

Radiation-induced skin injury remains one of the most common and challenging complications in clinical cancer radiotherapy. As the largest organ and the first target of radiation, the skin is susceptible to damage from free radicals and reactive oxygen species produced by radiation, which can impair cellular functions, including cell division, migration, and differentiation, ultimately leading to delayed wound healing and tissue damage^20,21. These injuries often .......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
4% Paraformaldehyde Fix Solution	Beyotime Biotech Inc (Beyotime) , China	P0099
Acorus calamus L. extract	Prepared in-house	N/A	The detailed preparation protocol is described in Section 4 of Protocol.
Anti-Bax Antibody	Wuhan servicebio technology Co., Ltd. (Wuhan, Hubei, China)	GB11690
Anti-Bcl-2 Antibody	Wuhan servicebio technology Co., Ltd. (Wuhan, Hubei, China)	GB113375
Anti-bFGF Antibody	Proteintech Group,Inc.(Wuhan, Hubei, China)	11234-1-AP
Anti-P53 Antibody	Wuhan servicebio technology Co., Ltd. (Wuhan, Hubei, China)	GB111740
Anti-VEGF Antibody	Wuhan servicebio technology Co., Ltd. (Wuhan, Hubei, China)	GB111971
BCA Protein Assay Kit	Wuhan servicebio technology Co., Ltd. (Wuhan, Hubei, China)	G2026-200T
Betamethasone Cream	United Pharmaceutical Co.,Ltd. (China)	N/A	Concentration: 0.1% w/w National Drug Approval No.: H19994057
Ethanol	Shanghai Aladdin Biochemical Technology Co., Ltd.	E111991	Used as the extraction solvent for the Acorus calamus L. extract.
Gel and Blot Imaging System	Bio-Rad Laboratories, Inc. (Hercules, CA, USA)	ChemiDoc MP
Hematoxylin-Eosin Stain Kit	Beijing Solarbio Science & Technology Co., Ltd.,(Beijing, China)	G1120
HRP conjugated Goat Anti-Rabbit IgG (H+L)	Wuhan servicebio technology Co., Ltd. (Wuhan, Hubei, China)	GB23303
Inverted Fluorescence Microscope	Olympus Corporation (Tokyo, Japan)	IX83
Masson’s Trichrome Stain Kit	Beijing Solarbio Science & Technology Co., Ltd.,(Beijing, China)	G1340
Microplate Reader (for absorbance, fluorescence, and luminescence detection)	Molecular Devices (San Jose, CA, USA)	SpectraMax iD3
petrolatum	Sinopharm Chemical Reagent Co., Ltd.(Shanghai, China)	N/A	Pharmaceutical-grade white petrolatum ; melting point: 45-60 °C;  National Drug Approval No.: H31022350
Rat IL-1β ELISA Kit	Beyotime Biotech Inc (Beyotime) , China	PI303
Rat IL-6 ELISA Kit	Beyotime Biotech Inc (Beyotime) , China	PI328
Rat TNF-α ELISA Kit	Beyotime Biotech Inc (Beyotime) , China	PT516
TUNEL Cell Apoptosis Detection Kit (DAB)	Beyotime Biotech Inc (Beyotime) , China	C1091