Psoriasis
In 2019, Perna et al. conducted a literature review on the effects of bergamot essential oil, extract, juice, and polyphenolic fraction on various health metrics. Thirty-one studies (20 involving humans with 1,709 subjects and 11 in rats and mice) were identified. Animal models indicated that bergamot essential oil (10 mg/kg or 20 mg/kg daily for 20 weeks) reduced psoriatic plaques, increased skin collagen content, and fostered hair growth and that bergamot juice (20 mg/kg) diminished proinflammatory cytokines. Human studies showed that bergamot extract and essential oil may reduce blood pressure and improve mental conditions.9
Vitiligo
In 2019, Shaaban et al. prepared elastic nanocarriers (spanlastics) to deliver psoralen-containing bergamot oil along with PUVB with the intention of harnessing melanogenic activity to treat vitiligo. Histopathologic assessment on rat skin was conducted before clinical treatment in patients with vitiligo. The spanlastics were deemed to be of suitable nanosize and deformable, yielding consistent bergamot oil release. The bergamot oil included in the nanocarrier was found to enhance photostability and photodynamic activity, with the researchers concluding that bergamot oil nanospanlastics with psoralen-UVB therapy shows potential as a vitiligo therapy.10
Two years later, Shaaban evaluated bergamot oil formulated in nanostructured lipid carriers as a photosensitizer for photodynamic treatment of vitiligo. The botanical oil was effectively used in the nanostructured lipid carriers with a gel consistency that delivered sustained release of the oil for 24 hours. Preclinical and clinical results in patients were encouraging for the topical photodynamic treatment of vitiligo, with the nanostructured lipid carriers improving the photostability and photodynamic activity of bergamot oil.6
Photoaging, photoprotection, and safety concerns
Three decades ago, an international cooperative study of the photophysical, photomutagenic, and photocarcinogenic characteristics of bergamot oil and the effect of UVA and UVB sunscreens found that UVB and UVA sunscreens at low concentration (0.5%-1%) in perfumes could not inhibit the phototoxicity of bergamot oil on human skin.11
In a 2015 study assessing the impact of 38% bergamot polyphenolic fraction (a highly concentrated Citrus bergamia fruit extract) on UVB-generated photoaging, Nisticò et al. found that the bergamot compound dose-dependently protected HaCaT cells against UVB-caused oxidative stress and photoaging markers. Suggesting that the high-antioxidant bergamot polyphenolic fraction has potential for use in skin care formulations, the researchers added that the extract seems to induce antiproliferative, immune-modulating, and antiaging activity.12In 2022, Alexa et al. performed in vitro tests and found that natural preparations containing bergamot, orange, and clove essential oils do not significantly alter physiological skin parameters and were deemed safe for topical use. An emulsion with bergamot essential oil was also found to reduce the viability of oral squamous cell carcinoma cells.13
Conclusion
As a photosensitizing agent, bergamot has an established role in skin care. Beyond its niche role in treatments for vitiligo and psoriasis, this botanical product appears to show potential as an anti-inflammatory agent as well as an ingredient to combat photoaging and skin cancer. Much more research is needed to elucidate the possible wider benefits of this Mediterranean staple.
Dr. Baumann is a private practice dermatologist, researcher, author, and entrepreneur in Miami. She founded the division of cosmetic dermatology at the University of Miami in 1997. The third edition of her bestselling textbook, “Cosmetic Dermatology,” was published in 2022. Dr. Baumann has received funding for advisory boards and/or clinical research trials from Allergan, Galderma, Johnson & Johnson, and Burt’s Bees. She is the CEO of Skin Type Solutions Inc., a SaaS company used to generate skin care routines in office and as an ecommerce solution. Write to her at dermnews@mdedge.com.
References
1. Juber M. Health benefits of bergamot. WebMD. November 29, 2022. Accessed March 21, 2023.
2. Sun P et al. Mediators Inflamm. 2020 Oct 6;2020:8868107.
3. Cristiano MC et al. Biomedicines. 2022 Apr 30;10(5):1039.
4. Liang Y et al. Phytother Res. 2021 Nov;35(11):6131-47.
5. Quetglas-Llabrés MM et al. Oxid Med Cell Longev. 2022 Apr 25;2022:8615242.
6. Shaaban M et al. Expert Opin Drug Deliv. 2021 Jan;18(1):139-50.
7. McNeely W, Goa KL. Drugs. 1998 Oct;56(4):667-90.
8. Han X, Beaumont C, Stevens N. Biochim Open. 2017 Apr 26;5:1-7.
9. Perna S et al. Food Sci Nutr. 2019 Jan 25;7(2):369-84.
10. Shaaban M et al. Drug Deliv Transl Res. 2019 Dec;9(6):1106-16.
11. Dubertret L et al. J Photochem Photobiol B. 1990 Nov;7(2-4):251-9.
12. Nisticò S et al. J Biol Regul Homeost Agents. 2015 Jul-Sep;29(3):723-8.
13. Alexa VT et al. Molecules. 2022 Feb 1;27(3):990.