Study

Comparative HPLC-MSn analysis of canine and human meibomian lipidomes: many similarities, a few differences

2011 · primary-comparison · peer reviewed: yes · record 22355543 · PubMed

8 findings kept from this study. Each is one sentence comparing an animal with a human, extracted from the full text, checked against the located page, and adjudicated against the review's definition of an animal-versus-human comparison.

The lipidomes of canine meibomian gland secretions and human meibomian gland secretions were found to be qualitatively similar.

Concordant · level C · laboratory dog · ophthalmology

“The lipidomes of cMGS and hMGS were found to be qualitatively similar, which implies similar biosynthetic and biodegradation pathways in canines and humans.”
page 1

The main lipid classes found in canine meibomian gland secretions were very long chain cholesteryl esters, wax esters, (O-acyl)-omega-hydroxy fatty acids (OAHFA), and cholesteryl esters of OAHFA, which are the same types of molecules found in humans.

Concordant · level C · laboratory dog · ophthalmology

“The main lipid classes found in cMGS were very long chain cholesteryl esters, wax esters, (O-acyl)-omega-hydroxy fatty acids (OAHFA), and cholesteryl esters of OAHFA. ... These are the same types of molecules that have previously been found in human and steer samples16, and in a range of other animals, including rodents, bovine, and marsupials (Butovich IA, et al. Invest. Ophth. Vis. Sci, 2009; 50:ARVO E-abstract 2545), gorilla (Wojtowicz JC, et al. Invest. Ophth. Vis. Sci., 2009; 51:ARVO E-abstract 4169), and dogs (Eule JC et al. Invest. Ophth. Vis. Sci., 2010; 51:ARVO E-abstract 4159).”
page 8

The levels of free cholesterol, diacylglycerols, and (O-acyl)-omega-hydroxy fatty acids present in human meibomian gland secretions were apparently lower than those detected in canine meibomian gland secretions.

Discordant · level C · laboratory dog · ophthalmology

“However, the levels of Chl, DAG, and OAHFA present in hMGS were apparently lower than those detected in cMGS, thus resulting in a more noticeable HPLC peak with RT 5–6 min in the latter case.”
page 3

Canine meibum had a higher ratio of oleic-acid based wax esters with odd numbers of carbons in their saturated alcohol moieties (mostly, C23 and C25) compared to human meibum, which showed a higher abundance of even-numbered alcohols (with C24 and C26 being the most prominent).

Discordant · level C · laboratory dog · ophthalmology

“Another apparent difference between the canine and human WE is the relative ratio of odd and even-chained alcohols: canine meibum has a higher ratio of oleic-acid based WE with odd numbers of carbons in their saturated alcohol moieties (mostly, C23 and C25), while human meibum shows a higher abundance of even-numbered alcohols (with C24 and C26 being the most prominent).”
page 6

The relative amount of unknown compounds with m/z 900\u20131100 was larger in canine meibum compared to human meibum.

Discordant · level C · laboratory dog · ophthalmology

“The major difference observed was in the relative amount of unknown compounds m/z 900–1100 (Fig. 1).”
page 9

Canine meibum had a relatively larger proportion of (O-acyl)-omega-hydroxy fatty acids (OAHFA) than human meibum.

Discordant · level C · laboratory dog · ophthalmology

“Canine meibum has a relatively larger proportion of OAHFA (minor HPLC with RT 4–6 min, Fig.1A) than human meibum.”
page 11

A highly reproducible pattern of wax ester signals m/z 605↑, 619↓, 633↑, 647↓, 661↑ was observed for canine meibum, while an inverse pattern 605↓, 619↑, 633↓, 647↑, 661↓ was observed for human meibomian gland secretions.

Discordant · level C · laboratory dog · ophthalmology

“A highly reproducible pattern of WE signals m/z 605↑, 619↓, 633↑, 647↓, 661↑ for canine meibum and an inverse pattern 605↓, 619↑, 633↓, 647↑, 661↓ for human MGS have been observed in each and every tested sample.”
page 11

Canine meibum was found to contain the same cholesteryl esters as human meibum, though the ratios of their individual cholesteryl ester components were not identical.

Mixed · level C · laboratory dog · ophthalmology

“Canine meibum was found to contain the same CE as human meibum, though the ratios of their individual CE components were not identical (Fig. 8).”
page 8