“Bisphosphonates are a safe and effective class of osteoporosis medication that have been the standard-of-care since the 1990s to prevent loss of bone and reduce the risk of fractures,” says senior creator Professor Mike Rogers, who heads the Bone Therapeutics Lab on the Garvan Institute.
“We have found an added potential benefit for this treatment – it can boost the immune function of lung cells, which may protect against respiratory infection and pneumonia. Our evidence warrants further investigation that we hope will lead to improved health outcomes in the older population, who are at higher risk of pneumonia and osteoporosis.”
Boost to immunity
Respiratory infections, similar to acute pneumonia, are a serious reason for loss of life from an infection worldwide. They more and more have an effect on the older inhabitants, as our means to generate protecting immune responses towards infectious illnesses declines with age.
“Previous clinical trials have suggested that bisphosphonate treatment has a beneficial effect in protecting against pneumonia,” says Dr Marcia Munoz, first creator of the paper. “In our research we wanted to understand why that is.”
The researchers administered a bisphosphonate referred to as zoledronic acid to mouse fashions and tracked how the medicine moved into completely different cells.
“It was previously thought that bisphosphonates act only in the bones, but we found that they are taken up by macrophages in the lung, which are ‘first responder’ cells that can recognise, engulf and destroy a pathogen during an immune response,” says Dr Munoz.
The crew then examined their mannequin’s immune response by exposing them to LPS, a molecule discovered on the floor of micro organism, which is often used to evaluate response to an infection. They discovered that even after only one bisphosphonate dose, the exercise of macrophages within the lung had elevated in comparison with mice that had not obtained the therapy.
“In the skeleton, bisphosphonates prevent bone loss by blocking an enzyme needed by the specialised cells that break down bone,” says PhD pupil Emma Fletcher, second creator of the paper. “In immune cells in the lung, we found that the treatment blocked the same enzyme, which in this case enhanced the immune response.”
Potential affect for well being
“Macrophages are one of the first lines of defense against infection,” says Professor Rogers. “If bisphosphonates are ramping up the ability of these cells to respond when they encounter a viral or bacterial infection, a stronger initial immune response may help clear the infection and lead to a better outcome. This is what we will be investigating next.”
“This leaves a large population of individuals who may receive additional benefits,” Professor Rogers provides. “Clinical trials are warranted to determine whether bisphosphonates, aside from preventing bone loss, can provide protection against pneumonia infection in vulnerable individuals, for instance, patients in aged care homes.”