Scientists uncover immune system’s role in bone loss
LOS ANGELES A new UCLA study sheds light on the link between high cholesterol and osteoporosis and identifies a new way that the body’s immune cells play a role in bone loss, the University announced Monday.
Published Aug. 20 in the journal Clinical Immunology, the research could lead to new immune-based approaches for treating osteoporosis, authors of the study noted. Affecting 10 million Americans, the disease causes fragile bones and increases the risk of fractures, resulting in lost independence and mobility.
Scientists have long recognized the relationship between high cholesterol and osteoporosis, but pinpointing the exact mechanism connecting the two has proved elusive.
“We’ve known that osteoporosis patients have higher cholesterol levels, more severe clogging of the heart arteries and increased risk of stroke. We also knew that drugs that lower cholesterol reduce bone fractures, too,” explained Rita Effros, professor of pathology at the David Geffen School of Medicine at UCLA. “What we didn’t understand was why.”
In the study, UCLA researchers focused on low-density lipoprotein (LDL) and examined how high levels of oxidized LDL affect bone and whether a type of immune cell called a T cell plays a role in the process.
Using blood samples from healthy human volunteers, the team isolated the participants’ T cells and cultured them in a dish. Half of the T cells were combined with normal LDL – the rest was combined with oxidized LDL. The scientists stimulated half of the T cells to mimic an immune response and left the other half alone.
“Both the resting and the activated T cells started churning out a chemical that stimulates cells whose sole purpose is to destroy bone,” Effros said. Called RANKL, the chemical is involved in immune response and bone physiology.
When Effros and her colleagues tested the T cells of the mice on the high-fat diet, they discovered that the cells acted differently than those of the mice on a normal diet.
The T cells switched on the gene that produces RANKL. The chemical also appeared in the animals’ bloodstream, suggesting that the cellular activity contributed to their bone loss.
“It’s normal for our T cells to produce small amounts of RANKL during an immune response,” explained Effros. “But when RANKL is manufactured for long periods or at the wrong time, it results in excessive bone damage.”
CDC, Reckitt Benckiser develop site to promote good health, hygiene
NEW YORK On the surface, this news highlights how serious the Centers for Disease Control and Prevention take that “prevention” piece of their title. The fact of the matter is the novel H1N1 influenza pandemic, the virus that ran rampant in the spring, giving the United States a little taste of what could come, will be the top billing this coming cough-cold-flu season. To date, the virus has not mutated in the past few months as it ran its course through the influenza season of the southern hemisphere, which means that Americans can expect more of the same here — an influenza strain that produces illness severity comparable to the seasonal flu but that favors younger people because they have no antibodies in reserve against this novel H1N1 virus.
Younger people not only means the twenty- and thirtysomethings in the workforce, it also means their school-age children. And given that children are oftentimes blamed for spreading colds and flu in a typical year, it only goes to reason that children may be a good spreader of the H1N1 pandemic virus, too. With this partnership, the CDC is making a robust effort in educating both children and their parents in proper cold/flu etiquette, because the cheapest way to nip this bug from the get-go is to inhibit its spread.
Going one level deeper, it also shows how quickly today’s administration will turn to private business in an attempt “to get things done.” The assumption here is that it’s not the CDC putting up the funds to launch this Web site, but Reckitt Benckiser. And in turn, Reckitt Benckiser gets a very credible driver around its Lysol disinfectant brand.
That bodes well for retail pharmacy and the healthcare companies that supply them. Because it bears a recognition what the private sector brings to the table — ready access to consumers who may be more apt to pay attention when the credibility of government agencies like CDC is married to the credibility associated with a venerable brand. Today it’s Reckitt Benckiser’s Lysol. Tomorrow it could very well be CVS or Walgreens.
FDA investigates liver injury claims from weight-loss medication users
NEW YORK This agency pulls no punches. The merest blip of a post-marketing serious adverse event report, and the agency is acting sooner than later. Because when you get right down to it, out of all the prescriptions for Xenical (approved for sale April 1999), out of all the people who have tried Alli when the ingredient orlistat was switched over the counter (in February 2007), there have been as many adverse events reported in the United States around orlistat and liver injury as there have been Boston Red Sox championships in the past 70 years: two.
That may be cause for concern. Because it taints the use of a product already approved for sale over-the-counter (and prescription-only in the case of Xenical) with a broad brush labeled “safety concern.” And with so few serious adverse event reports, that may be an unfair label causing some consumers who could benefit from the use of a product like alli not to try the product at all. And if these types of announcements become common, with so few serious adverse events to justify them, it could have the effect of making a public numb to any announced safety concerns.
Taking the other side, why might this be a good thing?
First, there is no actual recall here. Rather it’s a frank communication that a possible danger flag around the use of a product regulated by the FDA may be raised. And while this may certainly place the respective healthcare manufacturers on the defensive, it’s an indicator that the agency will aggressively live up to its mission statement — the protection of the American public.
There have been a host of criticisms around the agency’s ability to deliver on that promise leading up to this year. Contaminated prescription blood thinners and contaminated peanut butter are only the most recent examples of an agency with a somewhat tarnished safety reputation.
It’s good because actions such as these restore faith in the reputation of what is still considered the premier healthcare regulator in the world. And that’s important for all of the healthcare and food products around which there is no (or at least practically nonexistent) safety concern.
The challenge for those companies being called to the mat by FDA is educating the public around what the real issues are. In this case, it’s communicating to consumers that there has been no recall, and that the FDA is still recommending people use the products as directed. It’s communicating to consumers that safety concerns rank pretty high, with both the agency and the healthcare manufacturer. It’s communicating to consumers that those medicines available for sale over-the-counter are still real medicines, and that consumers need to follow usage directions.
Finally, it’s communicating to consumers that this is what they’ve asked for — the ability to make a healthcare decision with all the facts laid bare so that they and the healthcare professionals they look to for guidance can truly make a discerning decision about what’s right for them.