doi: 10.1080/21641846.2013.862993
Dark circles have two primary causes that are frequently conflated but require different active responses: vascular pooling in the blood vessels around the eye, which produces a bluish-purple discolouration most visible through thin skin in that area, and surface pigmentation from UV exposure, post-inflammatory marks, or accumulated melanin, which produces a brownish discolouration
Crucially, recent biochemical characterization has elucidated that this formation of gallate from 3-dehydroshikimate is catalyzed by two specific NADP+ dependent isoenzymes, EcDQD/SDH2 and EcDQD/SDH3, effectively linking the central shikimate pathway with downstream polyphenol biosynthesis (Tahara et al., 2020)
Cystic fibrosis and pancreatitis can also lead to destruction of the pancreas
Plasma total cysteine and cardiovascular risk burden: Action and interaction
A009984.