Wound Healing
Category
Skin
REVIEWED BY
Our Biomedical Scientist
Reviewed based on
Literature Review
Last update
December 2020
What is Wound Healing
Wound healing is a complex process that involves the repair of the skin or other body tissues after injury.1
Causes of Wounds
Wounds can have an internal or external origin.2
Internal origin wounds can occur due to disturbance of the different regulating systems of the human body and this may include:2
- Ischemia or stasis can lead to impaired circulation. Ischemia occurs when blood flow to the brain or heart is disrupted, brought on by the narrowing or blockage of blood vessels, which hinders blood circulation. Difficulties moving, immobilization for a long time, or failing in the valves located in the veins can cause statis. This results in blood pooling and failing to flow normally to the heart.
- Neuropathy: This is mostly found in people who have prolonged uncontrolled diabetes mellitus. In this case, accumulation of metabolites, derivative proteins, and high blood sugar occur which can lead to damage to the nervous system. Patients suffering from neuropathy can lose the sensation in the affected area, meaning that they can be unaware of wounds or trauma.
- Medical illnesses such as diabetes, AIDS, etc. can result in weakened immune system functions.
People can suffer from external wounds which can be either open or closed.
A closed wound indicates that an underlying tissue is affected but that a barrier (e.g., unbroken skin) exists between the wounded tissue and the outside environment. The most common types of closed wounds are:2
- Contusions are a common type of injury, often referred to as bruises. Commonly seen for people in sports and other activities which may lead to bruising. Trauma can lead to damage of small blood vessels and capillaries, muscles, and underlying tissue, as well as the internal organs or bone.
- Hematomas can be caused by any injury that can affect small blood vessels and capillaries leading to blood collecting and pooling in a limited space.
- Crush injuries occur when there is an external force that squeezes body part(s) between two objects causing damage ranging from a minor bruise to severe damage to that part of the body.
An open wound indicates damage to the skin, which leaves an underlying tissue exposed to the outside environment. Common types of open wounds include:2
- Abrasion is a type of wound that can occur due to rubbing against a rough surface or a smooth surface at high speed.
- Laceration is a type of wound, often referred to as a cut. Lacerations are usually deeper than abrasions and people can experience more pain and bleeding. Trauma or contact with an object can cause lacerations.
- Incision is a type of wound that can occur due to skin cut with a sharp object or surgical procedure. This type of wound can lead to serious impairments and can even endanger a person´s life.
- Puncture is a small, rounded wound that can occur due to objects with thin pointed tips like needles, nails, or teeth.
- Penetrating is a type of wound that can occur from an object that penetrates through the skin and reaches underlying organs or tissue. Penetrating wounds can lead to serious injury, especially if vital organs, major blood vessels or nerves are affected. This can also be life-threatening.
- Gunshot wounds are a type of wounds, referred to as penetrating wounds, brought on by bullets.
Wound healing process
Wound healing process consists of four phases: hemostasis, inflammation, proliferation, and remodeling (also known as maturation).
- Hemostasis, the first phase of wound healing, is initiated immediately after an injury. The aim of hemostasis is to stop bleeding in the wounded area. Platelets (thrombocytes) migrate to the wounded area and are involved in a clot-formation to reduce or stop the bleeding. The formation of the clot allows for recruiting other cells which play an important role in the process of wound healing.
- Inflammation, the second phase of wound healing, occurs one day after the injury. During inflammation, neutrophils migrate towards the injured area where they carry out phagocytosis, a process to eliminate foreign intruders. In the inflammatory phase, approximately 2-3 days after injury, the phagocytic activity is continued by tissue macrophages. Macrophages are also responsible for the activation and attraction of keratinocytes, fibroblasts, and endothelial cells.3
- Proliferation, the third phase of wound healing, consists of repairing wound damage and starting tissue remodeling. The central actions of the proliferative phase include: Fibroplasia (a process that involves fibrous tissue formation), reepithelization (a process that involves epithelium restoration), angiogenesis (development of new blood vessels), and peripheral nerve repair (a process that focuses on repairing damaged nerves).
- Remodeling, the fourth phase of wound healing, consists of completing tissue remodeling and restoring skin integrity.4
The connection between Cannabinoids & Wound Healing
Studies find that CBD may have great therapeutic potential and may be used to help treat Wound Healing. CBD and THC are well-known cannabinoids, however, they do not have the same psychoactive effects. THC is psychoactive while CBD does not possess psychoactive effects. According to WHO guidelines, the cannabidiol CBD is generally well tolerated with a good safety profile.
Preclinical research has suggested that cannabinoids can enhance wound closure and analgesia. In a prospective open-label cohort study, topical cannabis-based medicines were shown to promote wound closure and that the treatments were well tolerated with no adverse reactions.5
Try CANNASEN CBD Wound Healing Gel.
The literature discussion is an overview of the published results from scientific studies investigating if and how cannabinoids can be beneficial in the treatment of Insomnia. The overview will be updated regularly to ensure the newest and most accurate information.
CBD may exhibit anti-inflammatory activity beneficial in wound healing
In a study by Klein et al., with rats, the effect of CBD on oral wound healing was evaluated. Standardized ulcers were induced in rats and subsequently, they were injected with CBD at doses of 0 (control), 5 and 10 mg/kg daily intraperitoneally. It was concluded that CBD exhibits anti-inflammatory activity in an early phase of the wound healing process. However, there was not enough evidence to conclude that treatment with CBD leads to clinical improvement of oral ulcerative lesions.5
CB2 receptor agonists may serve as potential candidates for skin wound therapy
As discussed by Wang et al., previous studies found that multiple effector cells express CB2 receptors during skin wound healing. To verify whether this receptor may be involved in regulating skin wound healing, excisional wounds were induced in mice, and subsequently, they were treated with the CB2 receptor antagonist GP1a and the antagonist AM630. It has been found that wound healing could be improved by reducing inflammation, accelerating re-epithelialization, and diminishing scar formation through activation of the CB2 receptors. This suggests that CB2 receptor agonists may serve as potential candidates for skin wound therapy.6
In a study by Du et al., the effect of the CB2 agonists (JWH133 or GP1a) and the antagonist (AM630) on wound healing using a mouse model of an incised skin wound was assessed. It has been found that inflammation may be affected by regulating M1 rather than M2 macrophage subtype polarization through elevated levels of CB2 during incised skin wound healing.7
Clinical trials are research studies that examine new treatments and evaluate their effects on human health outcomes.
Study reported a 90% success rate in healing chronic wounds with cannabinoids
Rosner et al., discussed a recent study that reported a 90% success rate for healing chronic wounds when using experimental cannabinoid-based topical medicine. Thirty individuals participated in the open-label study where the recruited patients tested proprietary Topical Cannabis-Based Medicines. Out of the thirty patients, twenty-seven experienced that their wounds were completely healed. In some cases, the wounds had resisted healing for over a decade prior to this study.8
Topical application of cannabinoids reports great potential
In a prospective open-label cohort study by Maida et al., the effect of Topical Cannabis-Based Medicines (TCBM) in two elderly Caucasian women with recalcitrant Non-Uremic Calciphylaxis (NUC; a rare condition characterized by painful and intractable wounds) leg ulcers were evaluated. During the study, complete wound closure was achieved by daily TCBM application and the treatments were well tolerated without adverse reactions. Since TCBM was found to be effective in treating very challenging NUC wounds, this may suggest that TCBM has an even greater role to play for wound healing treatments.9
Chelliah et al., Tóth et al., discussed that topical CBD may improve the quality of life in people suffering from epidermolysis bullosa disease. Quicker wound healing, less blistering, and decreased pain were reported by all three patients, and the authors concluded that CBD may have anti-inflammatory properties.10,11
- Journal of Aesthetic & Reconstructive Surgery. Wound Healing. at <https://www.imedpub.com/scholarly/wound-healing-journals-articles-ppts-list.php>
- Wound Care Centers. Causes of Wounds. at <https://www.woundcarecenters.org/article/wound-basics/causes-of-wounds>
- Aduba, D. C. & Yang, H. Polysaccharide fabrication platforms and biocompatibility assessment as candidate wound dressing materials. Bioengineering 4, (2017). https://pubmed.ncbi.nlm.nih.gov/28952482/
- Cañedo-Dorantes, L. & Cañedo-Ayala, M. Skin acute wound healing: A comprehensive review. J. Inflam. 2019, (2019). https://www.hindawi.com/journals/iji/2019/3706315/
- Klein, Mariana, et al. Effects of cannabidiol, a Cannabis sativa constituent, on oral wound healing process in rats: Clinical and histological evaluation. Phyther. Res. 32, 2275–2281 (2018). https://pubmed.ncbi.nlm.nih.gov/30088305/
- Wang, Lin-Lin, et al. Pharmacological activation of cannabinoid 2 receptor attenuates inflammation, fibrogenesis, and promotes re-epithelialization during skin wound healing. Eur. J. Pharmacol. 786, 128–136 (2016). https://pubmed.ncbi.nlm.nih.gov/27268717/
- Du, Y., et al. Ren, P., Wang, Q., Jiang, S. K., Zhang, M., Li, J. Y., Wang, L. L. & Guan, D. W. Cannabinoid 2 receptor attenuates inflammation during skin wound healing by inhibiting M1 macrophages rather than activating M2 macrophages. J. Inflamm. (United Kingdom) 15, 1–12 (2018). https://pubmed.ncbi.nlm.nih.gov/30534003/
- Rosner, A. Cannabis-Based Medicine : A Breakthrough For Healing Intractable Chronic Wounds. (2019). https://www.forbes.com/sites/abbierosner/2019/07/09/cannabis-based-medicine-a-breakthrough-for-healing-intractable-chronic-wounds/?sh=44283269387b
- Maida, V., et al. Shi, R. B., Fazzari, F. G. T. & Zomparelli, L. Topical cannabis-based medicines – A novel paradigm and treatment for non-uremic calciphylaxis leg ulcers: An open label trial. Int. Wound J. 17, 1508–1516 (2020). https://onlinelibrary.wiley.com/doi/full/10.1111/iwj.13484
- Chelliah, Malcolm P., et al. Self‐initiated use of topical cannabidiol oil for epidermolysis bullosa. Dermatol. 35, e224–e227 (2018). https://pubmed.ncbi.nlm.nih.gov/29786144/
- Tóth, K. F., Ádám, D., Bíró, T. & Oláh, A. Cannabinoid signaling in the skin: Therapeutic potential of the ‘c(ut)annabinoid’ system. Molecules 24, (2019). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6429381/
CANNABINOIDS & RECEPTORS
Below you find the plant cannabinoids, cannabinoid receptors, and endocannabinoids that are associated with the potential therapy.
If you have any further information relevant to the connection between Wound Healing and cannabinoids or find any of the information inaccurate, outdated or incomplete please contact us here.
