PPAR gamma is expressed in numerous cell types, such as adipose tissues, muscles, brain, and immune cells.
Several groups have utilized different genetic methods to label cells and proteins for imaging of CNS ECs and their interaction with the brain and immune cells.
2-AG acts as full agonist on cannabinoid receptor type 1 (CB1R) and CB2R, which are mainly expressed in brain and immune cells, respectively.
Interestingly, the kynurenine pathway accounts for over 90% of tryptophan degradation in the periphery (63), and enzymes of this pathway are found in many organs/cell types, including liver, kidney, brain and immune cells.
In the acute phase, this catabolic response may be beneficial, providing amino acids for hepatic gluconeogenesis (supplying substrate for vital tissues such as the brain and immune cells) and for synthesis of proteins involved in immune function and in the acute-phase response.
Previous studies have shown that radiolabelled morphine is taken up and secreted by brain slices and immune cells [22], [35], [36], [37].
On the other hand, brain's immune cells, including microglia and/or invaded macrophages, also showed accumulation around tumor cells but did not show stronger correlation between tumor size and immune cell population (data not shown).
It plays important roles in the functions of brain, gastrointestinal tract, cardiovascular system, and immune cells.
Compared with UCP1 and UCP3 that are expressed more in the brown adipose tissue and skeletal muscle [ 1, 4, 5], expression of UCP2 is more ubiquitous and can be detected in liver, brain, pancreas, central nervous system and immune cells [ 4].
