Porphyrin Metabolisms in Human Skin Commensal Propionibacterium acnes Bacteria: Potential Application to Monitor Human Radiation Risk

Abstract

Propionibacterium acnes (P. acnes), a Gram-positive anaerobic bacterium, is a commensal organism in human skin. Like human cells, the bacteria produce porphyrins, which exhibit fluorescence properties and make bacteria visible with a Wood’s lamp. In this review, we compare the porphyrin biosynthesis in humans and P. acnes. Also, since P. acnes living on the surface of skin receive the same radiation exposure as humans, we envision that the changes in porphyrin profiles (the absorption spectra and/or metabolism) of P. acnes by radiation may mirror the response of human cells to radiation. The porphyrin profiles of P. acnes may be a more accurate reflection of radiation risk to the patient than other biodosimeters/biomarkers such as gene up-/down-regulation, which may be non-specific due to patient related factors such as autoimmune diseases. Lastly, we discuss the challenges and possible solutions for using the P. acnes response to predict the radiation risk.

Cutibacterium acnes (Propionibacterium acnes) and acne vulgaris: a brief look at the latest updates

“…Indeed, their ability to generate singlet oxygen from oxygen under ultraviolet exposure might enhance the production of cytotoxic substances by oxidation processes, such as squalene peroxide, a proinflammatory lipid . Moreover, they can stimulate the expression of keratinocyte‐derived interleukin (IL)‐8 and prostaglandin E2 that are mediators of inflammatory and immune responses . Interestingly, phylotype IA1 strains isolated from patients with acne were found to produce significantly higher levels of porphyrins than healthy skin‐associated phylotype II strains .…”

Evaluation of anti‐acne properties of phloretin in vitro and in vivo

“…Increased sebum excretion as well as alteration of the lipid composition and oxidant/antioxidant ratio of the skin surface lipids are major concurrent events associated with the development of acne. P. acnes produces porphyrins in large quantity, which exhibit fluorescence properties, making the bacteria visible . Compared to before treatment, the sebum secretion rate and amount of porphyrin significantly decreased at 4 weeks in the phloretin group.…”

“…Porphyrins are a group of organic compounds. Several porphyrins are known to play major roles in diverse processes, including oxygen transportation and photosynthesis [15]. In acne patients, P. acnes, found in the pilosebaceous unit, produces porphyrins which can be observed as a red fluorescence under a Wood's lamp.…”

Malignant melanoma and basal cell carcinoma detection with 457 nm laser-induced fluorescence

“…On the other hand role of flavins for living organisms is in dehydrogenation function in metabolism reactions and in coloring of tissues, as flavins play role in controlling photostimulated generation of melanin within the specialized cells [17]. Porphyrins also plays a significant role in metabolism processes, and not only in human skin, but also in bacteria living on human skin (such as Propionibacterium acnes) [18,19]. This makes possible to assume presence of significant changes in total content of flavins, lipo-pigments and porphyrins in different skin tissues during the nucleation and growth of tumors.…”