Effects of S-adenosyl-L-methionine (SAMe) supplementation on systemic oxidative stress and inflammatory biomarkers of adult dogs undergoing stress challenges

Zilinger, Angela

Permalink

https://hdl.handle.net/2142/122268 Copy

Description

Title

Effects of S-adenosyl-L-methionine (SAMe) supplementation on systemic oxidative stress and inflammatory biomarkers of adult dogs undergoing stress challenges

Author(s)

Zilinger, Angela

Issue Date

2023-12-08

Director of Research (if dissertation) or Advisor (if thesis)

R. C. de Godoy, Maria

Committee Member(s)

• Swanson, Kelly S.
• Fahey, Jr., George C.

Department of Study

Animal Sciences

Discipline

Animal Sciences

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• Antioxidant
• canine
• inflammation
• oxidative stress
• SAMe

Abstract

Supplementation of S-adenosyl-L-methionine (SAMe), a ubiquitous compound present in nearly all cells of the body, is associated with reduced levels of oxidative stress and inflammation in several chronic inflammatory diseases. However, there is limited knowledge of the safety and efficacy of supplementing SAMe as an antioxidant in healthy dogs undergoing oxidative stress-inducing conditions. Thus, the objective of this study was to evaluate the longitudinal effects of SAMe supplementation on serum metabolites and systemic biomarkers of oxidative stress and inflammation in healthy adult dogs undergoing stress challenges. Twenty adult Beagles (mean age = 5.05 ± 2.98 yr; mean BW = 12.23 ± 3.01 kg) and 20 adult Pointers (mean age = 2.80 ± 2.09 yr; mean BW = 21.68 ± 3.14 kg) were evenly stratified by breed (n=10) to 4 treatment groups in a completely randomized design. The treatment groups were a placebo pill without omega-6-PUFA as the control group (CON), a placebo pill with omega-6-PUFA as the dietary PUFA challenge (PUFA), a traditional formulation of SAMe with omega-6-PUFA as the dietary challenge (PATES), and a novel formulation of SAMe, hypothesized to have a higher bioavailability, containing phytic acid with omega-6-PUFA as the dietary challenge (PHY). The total study period consisted of 84 days. After 21 days on the control diet, each group remained on treatment for 63 days. On stress challenge days, the dogs were placed in a vehicle for 1 hour of transportation, followed by 15 min of visibly exhaustive treadmill exercise. Fasted blood samples were collected 14 days (day -14) before stress challenges and treatment, and serial collections were conducted on days 0, 21, 42, and 63. Blood samples were analyzed for serum chemistry, oxidative and inflammatory biomarkers, and plasma adenosyl-derivative concentrations. Treatment did not affect any analyzed serum metabolites besides an overall observed treatment-by-day trend (P = 0.0895) for serum glucose, where dogs receiving PUFA treatment tended to have the lowest serum glucose at day -14 compared with all other days within that treatment. Longitudinal oxidative stress biomarker analysis did not differ among treatments or among sampling days within treatments (P > 0.05). Longitudinal negative area under the curve (NAUC) (from 0 to 180 min) analysis in 4 out of 5 measured oxidative stress biomarkers did not differ among treatments or among sampling days within treatment (P > 0.05). Those with unchanged NAUC were cortisol, catalase, malondialdehyde (MDA), and 8-isoprostane. Longitudinal NAUC (from 0 min to 180 min) analysis for 8-hydroxydeoxyguanosine (8-OHdG), a marker of oxidative DNA damage, revealed significant changes in which CON and PHY treatments had a higher NAUC on day 21 compared with CON on days 0, 42, and 63, as well as PHY on days 42 and 63, and PATES on day 63 (P = 0.0360). Throughout the experimental period, pro-inflammatory cytokines and chemokines did not differ among dogs fed different treatments (P > 0.05). However, a treatment-by-day trend (P = 0.0852) was observed for keratinocyte chemoattractant-like (KC-like), a chemoattractant for neutrophils, as all treatments tended to be the lowest on day 63. These data suggest that these stress challenges did not induce robust oxidative stress and inflammatory responses among this healthy canine population. Moreover, the supplementation of SAMe had no detrimental effects on BW, BCS, or health parameters, and did not have an effect on systemic oxidative stress and inflammatory markers.

Graduation Semester

2023-12

Type of Resource

Thesis

Copyright and License Information

Copyright 2023 Angela Zilinger

Owning Collections