High-fat western diet-consumption alters crystalline silica-induced serum adipokines, inflammatory cytokines and arterial blood flow in the F344 rat

Abstract

Highlights Silica reduced serum leptin and adiponectin, no effects on body or fat pad weight. HFWD-consumption altered pro-inflammatory cytokines in silica-exposed animals. Silica altered pulse frequency; HFWD increased mean blood flow; effects additive. HFWD affected silica-induced metabolic effects.

High-fat Western diet consumption exacerbates silica-induced pulmonary inflammation and fibrosis

“…HFWD-consumption also increased BAL total cells, lymphocytes, neutrophils, and macrophages at 4 wk compared to the STD+AIR control cohort. These results indicate that consumption of a HFWD not only induced systemic inflammation, as shown earlier [25] , but that it also induced an inflammatory environment in the lung. We postulate that this HFWD-induced low-grade, systemic inflammation “primed” the lung and contributed to the exacerbated inflammatory response to silica dust inhalation.…”

“…Adiponectin has a protective role against lung injury [30] , [31] through its role of maintaining lung immune homeostasis [32] , [33] . Previously [25] , we found that, regardless of the diet consumed, silica-inhalation reduced both serum adiponectin and leptin at 8 wk in our animal model. Surprisingly, HFWD-consumption alone had lesser effects on adipokines in our animal model, which we attributed to the obesity-resistance of the F344 strain [34] .…”

“…Previously, we described the effects of HFWD consumption on systemic inflammation [25] . In that study, HFWD-consumption increased serum pro-inflammatory cytokines (IFN-γ, KC/GRO, TNF-α, IL-1β, IL-4, IL-5, IL-6, IL-10, IL-13) compared to STD+AIR-fed controls; however, there was no effect of the HFWD on blood cell count.…”

“…In Thompson et al [25] , silica inhalation’s profound effects on serum leptin and adiponectin levels were described: a significant reduction in both adipokines at 8 wk followed silica inhalation, regardless of whether animals were fed a HFWD or STD diet [25] . In the present study we found that HFWD-consumption significantly increased silica-induced lung inflammation and fibrosis at 8 wk.…”

“…This cycle of release and reuptake of silica particles, AM apoptosis, pulmonary inflammation, and fibrosis, all contribute to the progression of silicosis [21] , [22] , [23] , [24] . Previously, our laboratory demonstrated in a rat model that inhalation of crystalline silica markedly altered the profile of many metabolic and inflammatory changes caused by a HFWD [25] , i.e., silica-inhalation altered adipose function in animals with pre-existing HFWD-induced MetDys. Surprisingly, serum adipokines, leptin and adiponectin, as well as serum proinflammatory cytokines levels, were reduced at 8 wk after exposure to crystalline silica inhalation in animals that consumed a HFWD when compared to STD fed controls.…”