Chlorophyll derivatives as visual pigments for super vision in the red

Abstract

The primary event in vision is light-initiated activation of visual pigments. All visual pigments consist of the protein opsin bound to 11-cis-retinal and are responsible for initiating the transformation of light into an electrical signal. In a mouse model, we show that derivatives of chlorophyll can act as visual pigments initiating the transformation of light into an electrical signal and thus change the primary event in vision to initial activation of a chlorophyll derivative. Electroretinographic b-wave amplitudes recorded in response to red and blue light were two-fold greater in mice administered chlorin e(6), which accumulated in photoreceptor outer segments.

Light-harvesting chlorophyll pigments enable mammalian mitochondria to capture photonic energy and produce ATP

“…We previously observed that chlorophyll metabolites enabled photonic energy capture to enhance vision using a mouse model (Isayama et al, 2006;Washington et al, 2004;Washington et al, 2007). Because ATP can regulate a broad range of biological processes, we suspect that ATP modulation also played a role in vision enhancement.…”

Chlorophyll derivatives enhance invertebrate red-light and ultraviolet phototaxis

“…In fact, the UV and red-specific visual enhancement we detected in planarians firmly recapitulates the observations in mice from Washington et al . 11 ; as they noticed, wavelengths causing visual gain of function correspond to peaks in the absorption spectrum of Ce 6 . Furthermore, we showed that soaking animals in a Ce 6 -containing solution for a few minutes (see section “Photophobicity assay” in “Methods”) was sufficient to elicit drastic changes in visual perception.…”

“…Furthermore, we showed that soaking animals in a Ce 6 -containing solution for a few minutes (see section “Photophobicity assay” in “Methods”) was sufficient to elicit drastic changes in visual perception. Similarly, several groups found that in vertebrate models Ce 6 promptly reaches (within minutes) the ROS, even if the substance is administered systemically 11–14 . All in all, Ce 6 seems to have rapid uptake and to cause opsin spectral shift at specific wavelengths in invertebrates as much as in vertebrates.…”

“…Another study showed that living rod cells, extracted from the salamander Ambystoma tigrinum , respond better to red light if exposed to Ce 6 10 . When injected intravenously in a mouse model Ce 6 could rapidly accumulate in the ROS, and caused improved electroretinogram responses to red (>640 nm) and blue (456 ± 30 nm) wavelengths 11 . Intravenous administration of Ce 6 (or related compounds) in macaque and rabbit also led to bioaccumulation in the retina 12–14 .…”

Localisation and origin of the bacteriochlorophyll-derived photosensitizer in the retina of the deep-sea dragon fish Malacosteus niger

“…Perhaps more surprisingly, various chlorophyll-related compounds, such as chlorine e6, will interact with bovine rhodopsin to act as a photosensitizer for long wavelength illumination27, as well as enhancing thermal stability of the visual pigment28. Furthermore, they are also accumulated by isolated salamander rods29 and in the mammalian retina following intravenous injection3031, where they increase sensitivity to longwave illumination. These observations suggest that chlorophyll derivatives become easily incorporated into the retina of many vertebrates and interact with their visual pigments, even those species that do not usually contain such substances.…”