Because the soluble fraction of the particles may better penetrate the alveolar-capillary membrane and be in contact with the pulmonary vessels than the whole particles when inhaled, we determined whether the soluble fraction of UPs could activate
ERK1/2 and p38 MAPK.
Moreover, when the researchers exposed fat cells to lipopolysaccharide (LPS), one of the bacterial components that activates
TLR4, the cells began to make a related receptor, TLR2, and to synthesize secreted immune molecules such as interleukin-6.
Maloney and Waxman (1999) showed that MEHP activates
mouse and human PPAR[alpha] and [gamma] in a COS-1 cell-based transient trans-activation assay.
An agent that does not activate
AP-1 or ND[kappa]B is unlikely to act as a tumor promoter.
Several environmental agents activate
MAP kinases to cause cellular stress and cytotoxic responses, including bacterial products (such as lipopolysaccharide; LPS), pesticides, certain transition metals, and UV radiation (11-13).
The demonstration of a functional PPAR in human breast cancer cell lines that can bind specifically to a PPRE indicates that peroxisome proliferators may transcriptionally activate
peroxisome proliferator-regulated genes in human breast epithelial cells (53).
The more specific you can make the chemical you're going to activate
,' he says, "the more specific you can make the treatment.