As we know, long-term overnutrition, including consumption of a high-fat, high-fructose diet (HFD), can induce chronic low-grade inflammation in mice. However, we find a signifant low count of leukocytes as compared to the normal level. In detail, both lymphocyte and monocyte are significantly more reduced by HFD out of normal range, but not granulocyte. Generally, inflammation can increase leukocytes, especially neutrophils; however, our experiment showed different results. What are the conceivable reasons and mechanisms?
(I wonder if the best functioning will be with lipids?).
If it is not by ROS/iROS it may be directly by the fructose, either by the cell or by the receptors.
I will like to read the rest of the answers. A very interesting question.
Mª Angeles Zorrilla Lopez-Perea Thank you for your answer. I also found one study which mentioned fructose can induces leukocyte adherence to Veins in the mesenterium. Although we don't known if fructose can induces leukocyte adherence to the systemic veins, it might be one of the possible reasons for leukocyte count reduction.
Mattioli, L.F.; Holloway, N.B.; Thomas, J.H.; Wood, J.G. Fructose, but Not Dextrose, Induces Leukocyte Adherence to the Mesenteric Venule of the Rat by Oxidative Stress. Pediatric Research 2010, 67, 352-356, doi:10.1203/PDR.0b013e3181d00c41.
i think the answer for that observation is pretty simple.
high fat diets increase the mass of adipose tissue. some studies have shown that increasing adipose tissue mass leads to decreased plasma leptin hormone concentrations. also, other studies have shown that leptin stimulates haemopoiesis.
so in summary; high fat diet increase adipose tissue mass, thus decreases leptin, decreases haemopoiesis, and eventually leucokyte and monocyte counts.
you will find many papers relating plasma leptin concentration and haemopoiesis.
also, you will find many papers relating plasma leptin concentration and body mass index.
concerning HFD, since fructose tend to increase lipogenesis, the effect could be similar to what was previously mentioned