Osteoclasts Pump Iron

Hagfish pump some iron

Along with other nutrients, animals need trace metals to function. Iron, the oxygenbinding component in the blood pigment hemoglobin, is a critical trace metal and is usually absorbed through the gut. Mammals can alter iron metabolism in order to meet oxygen demand during periods of low environmental oxygen – hypoxia. However, it was unknown whether hagfish – a much more primitive group of anim...

Iron-deficiency anemia caused by a proton pump inhibitor.

A 59-year-old man was orally administered rabeprazole, a proton pump inhibitor (PPI), for gastroesophageal reflux disease, after which he gradually developed iron-deficiency anemia. The anemia did not improve following the administration of ferrous fumarate, and endoscopic screening of the entire gastrointestinal tract, including the small intestine, did not reveal any findings indicating the c...

Time to pump iron: iron-deficiency-signaling mechanisms of higher plants.

Iron is an essential nutrient for plants, yet it often limits plant growth. On the contrary, overaccumulation of iron within plant cells leads to oxidative stress. As a consequence, iron-uptake systems are carefully regulated to ensure that iron homeostasis is maintained. In response to iron limitation, plants induce expression of sets of activities that function at the root-soil interface to s...

Evidence for the presence of a proton pump of the vacuolar H(+)-ATPase type in the ruffled borders of osteoclasts

Microsomal membrane vesicles prepared either from chicken medullary bone or isolated osteoclasts were shown to have ATP-dependent H(+)-transport activity. This activity was N-ethylmaleimide-sensitive but resistant to oligomycin and orthovanadate, suggesting a vacuolar-type ATPase. Furthermore, immunological cross-reactivity of 60- and 70-kD osteoclast membrane antigens with Neurospora crassa va...

Cross-Presentation by Osteoclasts Induces