One-third of osteoporotic women taking oral bisphosphonates have elevated risk for bone fracture

Chemical structure of pyrophosphate (A, above) and bisphosphonates (B, below). P = phosphorus, O = oxygen, H = hydrogen, C = carbon, R = side chain. In bisphosphonates, the central oxygen atom is replaced with a carbon atom. All bisphosphonates share a common phosphorus-carbon-phosphorus motif with two side chains (R1 and R2 in the figure). The R2 side chain determines the chemical properties of the drug, and distinguishes individual types of bisphosphonates. This chemical structure affords a high affinity for calcium hydroxyapatite, allowing for rapid and specific skeletal targeting.

More than 53 million Americans age 50 and older, primarily women, have osteoporosis or are at high risk for the condition due to low bone density. A recent study of oral bisphosphonates, the most commonly prescribed osteoporosis treatment, found that approximately a third of women prescribed these drugs continue to be at elevated risk for bone fracture, an outcome that may have several origins.

Oral bisphosphonates are a pillar of preventive treatment for patients with osteoporosis and have been shown to be effective in reducing the risk of disabling bone fractures. It is known from clinical trials that no medication completely eliminates the risk of fracture. Additionally, medication effectiveness may be different in clinical practice compared to well-controlled research trials.

Research from the Regenstrief Institute-Merck (Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc.) collaboration suggests that many women still have indicators consistent with higher risk of fracture while taking these medications. The cross-sectional population health study was based on a retrospective database analysis of 7,435 women age 50 and older taking bisphosphonates for at least two years during the 2000-2012 time period. The analysis was published in the peer-reviewed journal Bone.

"While we found that a substantial proportion of patients who took oral bisphosphonates remain at risk for hip, spine, and other major fractures, this class of drug does improve bone density in the majority of patients and should remain a mainstay of osteoporosis management," said Erik Imel, M.D., the Indiana University School of Medicine endocrinologist and Regenstrief Institute-affiliated scientist who led the study.

"We limited our study to patients who were considered to be compliant with taking their medication, based on drug dispensing days covered, with the presumption being that those who filled prescriptions took the medication properly. We would expect even less benefit if patients fail to take their medication properly. To increase treatment effectiveness, patients and their doctors should be vigilant that the drug is taken reliably and properly. However, osteoporosis drugs are not enough. Physicians and their patients are well advised to discuss additional important modifications to decrease fall risk and fracture risk. These include exercise, smoking cessation, use of assistive devices such as canes or walkers, modifying the home to avoid obstacles that might lead to falls, and taking appropriate amounts of vitamin D and calcium."

Conducted under the auspices of a Regenstrief Institute-Merck collaboration, the retrospective cohort study utilized anonymized data from the Indiana Network for Patient Care, a health information exchange founded by the Regenstrief Institute. The study authors note that the data they used reflects real-life medical practice and patient behavior from a wide range of physicians and patient backgrounds. Adherence to bisphosphonate therapy was determined by prescription fulfillment records. Clinical data included information on bone density and fractures.

"We know that taking bisphosphonates decrease fracture risk compared to those not taking these drugs," Dr. Imel said. "But what about those women who weren't getting the anticipated benefit and are not improving bone density or even are losing bone density? What predicted that? The purpose of this study was to focus attention on those not doing well, in order to begin to decrease the odds of future fractures in this large group of vulnerable patients.

"Not everyone responds the same way to oral bisphosphonates or any drug. Various factors could convey continued risk of fracture in spite of bisphosphonate therapy, including other medical problems and risk factors for falling. Since we know that such a high percentage of women continue to have elevated fracture risk we -- doctors and patients -- need to focus on these factors," Dr. Imel said. "For example, we found that women who had other medical conditions in addition to low bone density--a frequent occurrence in this older population--had higher fracture risk. Taking some medications in combination with bisphosphonates seemed to increase fracture risk. However, having more medical conditions and taking more drugs are most likely markers of heightened risk rather than causative factors."

Neurologic problems, often linked to heightened risk of falls, as well as inflammatory and other chronic joint conditions including arthritis were found to be associated with higher odds of having a fracture among those taking bisphosphonates.

"I always tell my osteoporosis patients, 'Don't fall,'" said Dr. Imel. "They usually chuckle, and then we talk about things they can do to decrease the risk of falling, including proper footwear and assistive devices. Many patients are reluctant to use a cane or a walker. I try to get them to understand the importance of using any tool that decreases the chance of falling."

S-methylmethionine (Vitamin U) as antiulcer agent .......

About S-methylthionine :

S-Methylmethionine, or S-methyl-L-methionine, is a derivative of methionine In plants, it is produced from methionine by the enzyme methionine S-methyltransferase. S-Methyl- methionine is sometimes called vitamin U in naturopathic medicine, but it is not recognized as a vitamin by mainstream nutrition science. Methionine in itself has not been demonstrated as effective for treating peptic and duodenal ulcers. Its proponents claim that sources of methionine are limited, or claim it can be found only in raw cabbage; however, these claims are incorrect. Methionine is a common amino acid found in a wide variety of fruits, vegetables, and legumes.

More interesting results by the researchers from the Stanford University, have further substantiated the claim that it can be used to treat peptic and duodenal ulcers.

Acetaminophen is a pain reliever present in many over-the-counter cold and flu medicines. It is broken down, or metabolized, in the body into byproducts , one of which can be very toxic to the liver. At normal, therapeutic levels, this byproduct is easily deactivated when it binds to a naturally occurring, protective molecule called glutathione. But the body's glutathione stores are finite, and are quickly depleted when the recommended doses of acetaminophen are exceeded. Acetaminophen overdose is the most common cause of liver transplantation and the only effective antidote is an unpalatable compound called NAC that can induce nausea and vomiting, and must be administered as soon as possible after the overdose.

As per the claim by the authors, an enzyme called Bhmt2 helped to generate more glutathione. Bhmt2 works by converting the diet-derived molecule S-methylmethionine, or SMM, into methionine, which is subsequently converted in a series of steps into glutathione. The researchers confirmed the importance of the pathway by showing that SMM conferred protection against acetaminophen-induced liver toxicity only in strains of mice in which the Bhmt2 pathway was functional.

By administering SMM, which is found in every flowering plant and vegetable, we were able to prevent a lot of the drug’s toxic effect,” said Peltz. He and his colleagues are now working to set up clinical trials at Stanford to see whether it will have a similar effect in humans. In the meantime, though, he cautions against assuming that dosing oneself with SMM will protect against acetaminophen overdose....

Source : http://med.stanford.edu/ism/2009/november/peltz.html

Vitamin A Compound Might Aid in Colon Cancer Fight

In continuation of my update on Retinoic acid

Retinoic acid, a compound derived in the body from vitamin A, might have a role in suppressing colon cancer, new animal research suggests.

"Retinoic acid has been known for years to be involved in suppressing inflammation in the intestine," said study senior author Dr. Edgar Engleman, professor of pathology and medicine at Stanford University School of Medicine in Palo Alto, Calif.

Meanwhile, the development of colon cancer has been linked to inflammation. For example, inflammatory bowel disease, such as ulcerative colitis, has been associated with colon cancer, he said in a university news release.

"We wanted to connect the dots and learn whether and how retinoic acid levels directly affect cancer development," Engleman added.

When the researchers looked at mice with colon cancer, they saw lower levels of retinoic acid in the intestines of the mice.

The researchers also found that boosting levels of retinoic acid in the intestines of mice with colon cancer slowed progression of the disease.

In humans, colon cancer patients who had high levels of a protein that degrades retinoic acid in their intestinal tissue tended to have worse outcomes than other patients, the study authors noted.

The findings suggest new ways to prevent or treat colon cancer. However, it's important to note that animal research doesn't always produce the same results in humans.

"The intestine is constantly bombarded by foreign organisms. As a result, its immune system is very complex," Engleman said.

"We found that bacteria, or molecules produced by bacteria, can cause a massive inflammatory reaction in the gut that directly affects retinoic acid metabolism," he said.

He said that retinoic acid levels are normally regulated very tightly.

"Now that we've shown a role for retinoic acid deficiency in colorectal cancer, we'd like to identify the specific microorganisms that initiate these changes in humans. Ultimately we hope to determine whether our findings could be useful for the prevention or treatment of colorectal cancer," he concluded.

The study was published online Aug. 30 in the journal Immunity.

Daily Multivitamin May Protect Against Cognitive Decline in Older Adults

In continuation of my update on Vitamin and their importance 

A daily multivitamin may provide cognitive benefits for older adults, according to a study published online Sept. 14 in Alzheimer’s & Dementia.

Laura D. Baker, Ph.D., from the Wake Forest University School of Medicine in Winston-Salem, North Carolina, and colleagues assessed whether daily use of cocoa extract (containing 500 mg/day flavanols) versus placebo and a commercial multivitamin-mineral (MVM) versus placebo improved cognition in 2,262 older women and men (mean age, 73 years).

The researchers found that cocoa extract had no effect on global cognition. However, compared with placebo, daily MVM supplementation resulted in a statistically significant benefit on global cognition, with a more pronounced effect seen in participants with a history of cardiovascular disease. Benefits of MVM were also seen for memory and executive function. There were no significant interactions observed between cocoa extract and MVM for any of the cognitive composites.

"Our study showed that although cocoa extract did not affect cognition, daily multivitamin-mineral supplementation resulted in statistically significant cognitive improvement. This is the first evidence of cognitive benefit in a large longer-term study of multivitamin supplementation in older adults," Baker said in a statement. "It's too early to recommend daily multivitamin supplementation to prevent cognitive decline. While these preliminary findings are promising, additional research is needed in a larger and more diverse group of people."

Ref : Daily Multivitamin May Protect Against Cognitive Decline in Older Adults 

Carnitine supplement may improve survival rates of children with heart defects

We know that, Carnitine is a quaternary ammonium compound biosynthesized from the amino acids lysine and methionine. In living cells, it is required for the transport of fatty acids from the cytosol into the mitochondria during the breakdown of lipids (fats) for the generation of metabolic energy. It is widely available as a nutritional supplement. Carnitine was originally found as a growth factor for mealworms and labeled vitamin B_T, although carnitine is not a proper vitamin. Carnitine exists in two stereoisomers: Its biologically active form is L-carnitine, whereas its enantiomer, D-carnitine, is biologically inactive.

New research shows it appears to normalize the blood vessel dysfunction that can accompany congenital heart defects and linger even after corrective surgery, said Dr. Stephen M. Black, cell and molecular physiologist at the Vascular Biology Center at the Medical College of Georgia at Georgia Regents University.

"My hope is this is going to have a major, major impact on survival of babies," Black said. About half the babies born with heart defects have excessive, continuous high pressure on their lungs from misdirected blood flow. Early surgery can prevent full-blown pulmonary vascular disease, but scientists are finding more subtle disruptions in the signaling inside blood vessels walls that can be problematic -- even deadly -- up to 72 hours after surgery.

The good news is the changes are reversible and that carnitine speeds recovery and can even prevent the damage in a lamb model of these human heart defects, according to studies published in the journal Pediatric Research.

Carnitine supplement may improve survival rates of children with heart defects

Is Green Tea a Fad or a Real Health Boost?

In continuation of my updates on Green tea

Green tea is a popular health trend, with many people sipping in hopes of deriving benefits from the brew.

There's nothing wrong with that, dietitians say -- green tea is a healthy drink loaded with antioxidants. But the jury's still out on many of its purported health benefits.

"Clinical trials related to green tea are still in their early stages," said Nancy Farrell Allen, a registered dietitian nutritionist in Fredericksburg, Va. "I say drink it, enjoy it. It's not going to hurt, and it might have worthy benefits to it. But nutrition is a science, and it takes time for our understanding to evolve."

Green tea's potential health benefits derive from catechins, which are powerful antioxidant compounds known as flavonoids, said Chelsey Schneider, clinical nutrition supervisor at Mount Sinai Beth Israel Cancer Center in New York City.

One catechin in particular, known as EGCG, is found at higher levels in green tea than in either white or black tea, she said.

"This compound can be even stronger than vitamin C and E, which are very, very strong antioxidants," Schneider said. Antioxidants help prevent damage to cells.

Green, black and white tea all come from the same plant, said Allen, who is a spokeswoman for the Academy of Dietetics and Nutrition.

Green tea is made from the leaves of the mature plant, while white tea is made of leaves plucked early in development. Black tea is made from green tea leaves that are laid out and covered with a damp cloth, she said.

"They dry and blacken and ferment a little, giving black tea that darker, richer flavor," Allen said. But this process also reduces levels of catechins in black tea.

Weight loss has been associated with green tea, with experts suggesting that its mixture of caffeine and catechins can enhance a person's metabolism and processing of fat, according to the University of California-Davis Department of Nutrition.

But it appears that folks have to drink a lot of green tea to get substantial weight loss benefits and carefully watch the rest of their diet, UC-Davis says.

Green tea also has been tied to heart health.

For example, green tea was shown to reduce "bad" LDL cholesterol in a 2018 study of more than 80,000 Chinese published in the Journal of the American Heart Association.

Evidence suggests catechins in green tea also could lower risk of heart attacks, help blood vessels relax and reduce inflammation, UC-Davis says.

Green tea even has been associated with a lower risk of some cancers.

The American Cancer Society says studies have linked green tea to a reduction in ovarian cancer risk. And UC-Davis said experimental models have shown that green tea might reduce risk of a variety of other cancers.

But a 2016 evidence review by the Cochrane Library concluded that there is "insufficient and conflicting evidence to give any firm recommendations regarding green tea consumption for cancer prevention."

Schneider said the research is limited. "Some small studies say green tea can maybe be preventative for certain cancers, like breast, ovarian, endometrial, pancreatic and oral cancers, but there aren't so many conclusive human trials that support that," she said.

Green tea also might help keep your brain younger. A 2014 study in the journal PLOS One found that Japanese who drank more green tea had significantly less decline in brain function, although researchers couldn't rule out the possibility that these folks might have other healthy habits that helped keep them mentally sharp.

One caveat with all of this research is that it tends to take place in Asian countries, where people drink much more green tea. There might be significant differences for Americans.

And the way you take your green tea could diminish any potential positive effects, Schneider added.

"A lot of people are adding processed white sugar to their green tea, which really makes something beautiful and healthy into something unhealthy," she said.

Adding milk or cream to your tea also might not be a good idea.

"There are some studies that say having milk in green tea can actually block the effects of you absorbing the antioxidant," Schneider said. "If it was me, I'd drink it straight up."

Compound prevents neurological damage, shows cognitive benefits in mouse model of Alzheimer’s disease

The supplement nicotinamide riboside (NR) – a form of vitamin B3 – prevented neurological damage and improved cognitive and physical function in a new mouse model of Alzheimer’s disease. The results of the study, conducted by researchers at the National Institute on Aging (NIA) part of the National Institutes of Health, suggest a potential new target for treating Alzheimer’s disease. The findings appear in the Feb. 5, 2018, issue of Proceedings of the National Academy of Sciences.

NR acts on the brain by normalizing levels of nicotinamide adenine dinucleotide (NAD+), a metabolite vital to cellular energy, stem cell self-renewal, resistance to neuronal stress and DNA repair. In Alzheimer’s disease, the brain’s usual DNA repair activity is impaired, leading to mitochondrial dysfunction, lower neuron production, and increased neuronal dysfunction and inflammation.

“The pursuit of interventions to prevent or delay Alzheimer’s and related dementias is an important national priority,” said Richard J. Hodes, M.D., director of the NIA. “We are encouraging the testing of a variety of new approaches, and this study’s positive results suggest one avenue to pursue further.”

The international team of scientists was led by Vilhelm A. Bohr, M.D., Ph.D., senior investigator and chief of the Laboratory of Molecular Gerontology of the NIA’s Intramural Research Program, with Dr. Yujun Hou, a postdoctoral investigator in the laboratory.

Based on their studies in human postmortem brain, they developed a new strain of mice mimicking major features of human Alzheimer’s such as tau pathology, failing synapses, neuronal death and cognitive impairment. Using this animal model, the researchers tested the effects of an NR supplement by adding it to the drinking water of the mice. Over a three-month period, researchers found that mice who received NR showed reduced tau in their brains, but no change in amyloid-beta.

The NR-treated mice also had less DNA damage, higher neuroplasticity (activity and reorganization of brain cells associated with learning or memory), increased production of new neurons from neuronal stem cells, and lower levels of neuronal damage and death. In the hippocampus area of the brain – in which damage and loss of volume is found in people with dementia – NR seemed to either clear existing DNA damage or prevent it from spreading further.

The NR-treated mice also performed better than control mice on multiple behavioral and memory tests, such as water mazes and object recognition. NR mice also showed better muscular and grip strength, higher endurance, and improved gait compared to their control counterparts. The research team believes that these physical and cognitive benefits are due to a rejuvenating effect NR had on stem cells in both muscle and brain tissue.

“We are encouraged by these findings that see an effect in this Alzheimer’s disease model,” said Dr. Bohr. “We are looking forward to further testing of how NR or similar compounds might be pursued for their possible therapeutic benefit for people with dementia.”

Next steps for the research team include further studies on the underlying mechanisms and preparations towards intervention in humans.

The team’s work also included contributions from researchers at the Danish Aging Research Center at the University of Aarhus, and the Center for Healthy Aging at the University of Copenhagen. The Bohr lab has a Cooperative Research and Development Agreement -- which allows NIH investigators to join colleagues from industry and academia to pursue common research goals -- with ChromaDex Corp.

Compound prevents neurological damage, shows cognitive benefits in mouse model of Alzheimer’s disease