All posts in l-z

Osteoperosis may be a paediatric disease

Print pagePDF pageEmail page

The researchers fed 12 piglets a calcium-rich diet and another 12 piglets a calcium-deficient diet during the first 18 days of their lives. When the researchers examined samples of bone marrow, organs, and hind leg bone at the end of the study, they found that the piglets fed a calcium-deficient diet had compromised bone density and strength. The bone marrow tissue of these same piglets also seemed to be predisposed to become fat cells rather than osteoblasts (bone-forming cells). The presence of fewer osteoblasts during infancy may result in a reduced ability of bones to grow and repair themselves during later years.

Osteoporosis affects an estimated 10 million men and women in the United States, with about 80 percent of cases diagnosed in women. According to the National Osteoporosis Foundation, approximately 34 million additional people are believed to have low bone mass, which places them at increased risk for osteoporosis. Most people who have osteoporosis or low bone mass do not even know they have it, and the first clue is often a fracture associated with a fall or, in severe cases, simply bending over or turning around.

The lead researcher, Dr. Chad Stahl, an associate professor in the Department of Animal Science at North Carolina State University, noted that maintaining good calcium nutrition for children and adolescents is known to be important, but that this recent study “suggests that calcium nutrition of the neonate may be of greater importance to life-long bone health due to its programming effects on mesenchymal stem cells” (bone marrow tissue from which osteoblasts are formed). This idea might cause healthcare professionals “to begin thinking about osteoporosis not so much as a disease of the elderly, but instead as a pediatric disease with later onset.”

More

Cigarette Smoking and Fructose Exacerbate Liver Disease

Print pagePDF pageEmail page

NAFLD is the most common cause of liver disease worldwide and research suggests the number of cases will climb given an increasing trend toward higher fat diets, obesity, decreased physical activity, and a rise in diabetes. Past studies indicate that more than 30 million Americans have NAFLD and approximately 8 million may have nonalcoholic steatohepatitis (NASH).

In the first study, Ramón Bataller, M.D., and colleagues from the Hospital Clínic in Barcelona, Spain investigated the effects of cigarette smoking (CS) in obese rats. Rats were divided into 4 groups (n=12 per group): obese smokers, obese non-smokers, control smokers and control non-smokers. Smoker rats were exposed to 2 cigarettes/day, 5 days/week for 4 weeks. Researchers found that obese rats exposed to CS showed a significant increase in ALT serum levels (indicating liver disease), while this effect was not observed in control rats.

“Our results show that CS causes oxidative stress and worsens the severity of NAFLD in obese rats,” said Dr. Bataller. “Further studies should investigate longer exposures to CS, and assess whether this finding also occurs in patients with obesity and NAFLD.”

In her editorial, also published in Hepatology this month, Claudia Zein, M.D., from the Cleveland Clinic, noted that “the importance of these results is that taken together with other experimental and clinical data, they support that cigarette smoking appears to aggravate liver injury in patients with liver disease.” Dr. Zein added, “Studies characterizing the effects of cigarette smoking in human NAFLD will be crucial because of the vast number of patients that may benefit from modification of this risk factor.”

Additionally, prior studies suggest an over consumption of high fructose corn syrup (HFCS), primarily in the form of soft-drinks, have contributed to weight gain and the rise in obesity, particularly in children and adolescents. Table sugar (sucrose) and HFCS are the two major dietary sources of fructose. Over the past 40 years, consumption of dietary fructose has increased 1,000% according to Bray et al, and doctors believe it to be a major cause of NAFLD.

Researchers from Duke University studied 341 adults enrolled in the NASH Clinical Research Network who responded to a Block food questionnaire within 3 months of a liver biopsy. Fructose consumption was estimated conservatively by including that found in beverages, which accounts for 50% of dietary fructose intake. Results showed that 27.9% of participants consumed at least 1 fructose-containing beverage per day, 52.5% had 1 to 6 beverages with fructose per week, and 19.7% drank no beverages with fructose.

“In patients with NAFLD, daily fructose ingestion was associated with reduced fatty liver (steatosis), but we found increased fibrosis,” noted Manal Abdelmalek, M.D., M.P.H, and lead author of the study. “Further dietary intervention studies are needed to evaluate whether a low-fructose diet improves metabolic disturbances associated with NAFLD and improves patient outcomes for those at risk of disease progression,” concluded Dr. Abdelmalek.

A second fructose study led by Ling-Dong Kong, M.D., from Nanjing University in China investigated the effects of curcumin on fructose-induced hypertriglyceridemia and fatty liver in rats. Curcumin, a compound derived from turmeric (curcuma root), is sold as an herbal supplement and is believed to have anti-inflammatory, anti-tumor, and anti-viral properties. Researchers observed a hyperactivity of hepatic protein tyrosine phosphatase 1B (PTP1B), which is associated with defective insulin and leptin signaling, in fructose-fed rats.

For the first time this study demonstrated that curcumin inhibited hepatic PTP1B expression and activity in fructose-fed rats. “Our results provide novel insights into the potential therapeutic mechanisms of curcumin on fructose-induced hepatic steatosis associated with insulin and leptin resistance,” said Dr. Kong.

These studies indicate modifying risks such as smoking and fructose consumption offer potential benefits for those with liver diseases. Further studies are needed to explore these benefits in preventing the progression of liver disease.

More

Say No to Diet Soft Drinks

Print pagePDF pageEmail page

In previous research, scientists using information collected from the National Health and Nutrition Examination Survey (NHANES), a long-term collection of studies designed to assess the health and nutritional status of adults and children in the US, had found a link between sugar containing sodas and urinary protein. However, they did not collect data on any kidney function changes related to drinking sweetened sodas. So, in their second study, Dr. Lin and Dr. Curhan, decided to specifically check for any kidney function decline in women who drink sodas regularly. Once again, they used data from the Nurses' Health Study.

In a statement for the media, Dr. Lin reported they found “a significant two-fold increased odds, between two or more servings per day of artificially sweetened soda and faster kidney function decline; no relation between sugar-sweetened beverages and kidney function decline was noted.” Moreover, this association persisted even when the researchers accounted for age, obesity, high blood pressure, cardiovascular disease, physical activity, calorie intake, diabetes and cigarette smoking. Clearly, artificially sweetened sodas are detrimental to kidney health.

“There are currently limited data on the role of diet in kidney disease,” said Dr. Lin in a statement to the press. “While more study is needed, our research suggests that higher sodium and artificially sweetened soda intake are associated with greater rate of decline in kidney function.”

More

Lancet Series Examines TB Worldwide

Print pagePDF pageEmail page

One article warns that the absence of major investments in new technology and prevention and treatment tools could make drug-resistant strains of TB the “dominant” form of TB over the coming decades, according to the news service (5/18). The article notes “that India and China had around 50 percent of the global MDR-TB burden, followed by Russia with 9 percent,” Reuters writes. The authors write, “The future possibility of strains that are totally resistant to all anti-tuberculosis drugs is not inconceivable.”

“In other studies in the series … scientists said the combined impact of new drugs, vaccines, and diagnostic tests could cut worldwide incidence of TB by 94 percent by 2050,” the news service reports. According to experts, only about a quarter of the funding needed for drug research and development is available.

“Development of new drugs for TB is lengthy, expensive, and risky, and the expected revenues are too small to justify commercial investment,” Zhenkun Ma of the Global Alliance for TB Drug Development and co-authors write in a paper. “New financing and market incentive mechanisms are needed.”

The journal also notes that “there are 11 potential TB vaccines being tested in human trials and up to 10 experimental medicines in the TB drug 'pipeline.' Since many drugs fail in late-stage trials, this handful of possibilities is unlikely to be enough,” Reuters reports (Kelland, 5/18).

The series also focused on the broader issues that contribute to the spread of TB, the Associated Press reports. “Experts said TB isn't only a medical problem, but is intertwined with poverty, as it spreads widely among people living in overcrowded, dirty places. They said TB programs need to go beyond health and include other sectors like housing, education and transportation,” the news service writes. Philip Stevens, a health policy expert at the International Policy Network, said the disease “cannot be tackled in isolation,” noting that the focus of control efforts should be on “economic growth, which is outside the control of the U.N.” (Cheng, 5/18).

“In the eighth and final paper … a call to action is made to a wide range of sectors to assist scale-up TB service delivery, research and control. The launch of The Lancet TB Observatory, which will monitor progress on key indicators on an ongoing basis, is also announced,” according to a Lancet press release. The Observatory, which is a collaboration between the Lancet, the Stop TB Parternship, the WHO and the Global Fund to Fight AIDS, Tuberculosis, and Malaria, “will assess and monitor” TB research, financing and other information. In a comment discussing the Observatory, Lancet Editor-in-Chief Richard Horton and Executive Editor Pamela Das observe that currently “there is no formal mechanism to assess this information critically and independently. Nor is there any means to hold the various stakeholders in tuberculosis control to account” (5/18).

The series also includes comments about how to scale-up an integrated TB and HIV response, the burden of the disease in women and children and how migration patterns within and between countries contribute to the spread of TB. 

More

Folate Helps Repair Damage Due to Ageing

Print pagePDF pageEmail page

Since the 1960s, researchers have been studying how the water-soluble vitamin supports the healthy functioning of cells. They discovered that it's essential for cell division and replication, making it especially important for expectant mothers.

It's also important to proper replication of DNA and RNA — a lack of folate has been linked to genetic mutations that can lead to cancer.

Folate is commonly found in leafy green vegetables like spinach and turnip greens. Since 1998, the U.S. Food and Drug Administration has mandated that many foods, such as rice, flour and cornmeal, be enriched with a synthetic folate known as folic acid.

While folate deficiency is no longer a problem in the U.S., it remains widespread in developing nations and much of Europe, where enriching grain products is not widely practiced.

This new research, funded by the National Science Foundation and originally sparked by funding from the U.S. Department of Energy, links folate to the production or repair of compounds called iron-sulfur clusters through a recently discovered intermediary protein called COG0354.

These clusters are part of the mechanism cells use to produce energy and carry out other vital reactions. But they are also sensitive to a byproduct of the energy-producing process: highly reactive oxygen-based molecules, some of which are called free radicals.

The oxidative stress caused when these molecules pollute a cell has been linked to cell death and aging, as well as to conditions such as atherosclerosis, Parkinson's disease, heart disease, Alzheimer's, fragile X syndrome and many more.

Examining the folate-iron-sulfur cluster link required the team to pull experience from not only UF's microbiology and cell science and food science and human nutrition departments, but also the McKnight Brain Institute and the National High Magnetic Field Laboratory.

Expertise from the latter two institutions was needed because the researchers used nuclear magnetic resonance analysis to observe folate interacting with COG0354 protein — molecular-scale activity that could otherwise only have been shown indirectly, said Arthur Edison, the NHMFL's director of chemistry and biology and an associate professor with UF's biochemistry and molecular biology department.

The researchers have found that COG0354 is present in creatures from each of the six kingdoms of life, from mice and plants to one-cell organisms that may predate bacteria.

The findings will open new avenues of study into the overall mechanism of oxidative stress repair, and may someday lead to new medicines. For now, the researchers emphasize that this is another example of the vitamin's importance in one's diet.

More

Clearing Up Confusion

Print pagePDF pageEmail page

People with lactose intolerance do not produce enough of the enzyme lactase to break down lactose (the form of sugar naturally found in milk). Instead, when people with lactose intolerance ingest large amounts of dairy products, or foods or medicines containing lactose, lactose stays in the intestinal tract until it reaches the colon where it can cause gas, bloating, stomach cramps or diarrhea.

Last February, the National Institutes of Health (NIH) released a statement on lactose intolerance and health to provide health care providers, patients and the general public with the latest information on the topic.

“What many people fail to understand is that lactose intolerance is not an all-or-nothing situation,” says Susan Nitzke, professor of Nutritional Sciences at the University of Wisconsin-Madison and nutrition specialist with the University of Wisconsin-Extension.

Nitzke points out that many people with lactose intolerance can consume small amounts of lactose–for example, a half cup of milk or yogurt–without experiencing any symptoms. “This is especially true if the milk or other lactose-containing food is consumed with a meal,” she says.

Nitzke urges people to consult their doctor or a dietitian (like Nastaran) before making drastic dietary changes for suspected lactose intolerance. Your doctor may do a blood, breath or stool test to find out if lactose intolerance is the true cause of your digestive problems.

Milk and dairy foods provide many important nutrients. Milk is a well-known source of calcium and vitamin D. “Dairy products are also excellent sources of protein, potassium and many other vitamins and minerals,” says Mallory Koenings, a graduate student in the Department of Nutritional Sciences at UW-Madison.

Because dairy products contain so many important nutrients, even people who are lactose-intolerant are urged to consider alternatives within the milk food group, such as yogurt or lactose-free milk.

More

Indian Spice May Delay Liver Damage

Print pagePDF pageEmail page

Curcumin, one of the principal components of the Indian spice turmeric, seems to delay the liver damage that eventually causes cirrhosis, suggests preliminary experimental research in the journal Gut. Curcumin, which gives turmeric its bright yellow pigment, has long been used in Indian Ayurvedic medicine to treat a wide range of gastrointestinal disorders.

Previous research has indicated that it has anti-inflammatory and antioxidant properties which may be helpful in combating disease. The research team wanted to find out if curcumin could delay the damage caused by progressive inflammatory conditions of the liver, including primary sclerosing cholangitis and primary biliary cirrhosis.

Both of these conditions, which can be sparked by genetic faults or autoimmune disease, cause the liver's plumbing system of bile ducts to become inflamed, scarred, and blocked. This leads to extensive tissue damage and irreversible and ultimately fatal liver cirrhosis.

The research team analysed tissue and blood samples from mice with chronic liver inflammation before and after adding curcumin to their diet for a period of four and a period of eight weeks.

The results were compared with the equivalent samples from mice with the same condition, but not fed curcumin.

The findings showed that the curcumin diet significantly reduced bile duct blockage and curbed liver cell (hepatocyte) damage and scarring (fibrosis) by interfering with several chemical signalling pathways involved in the inflammatory process.

These effects were clear at both four and eight weeks. No such effects were seen in mice fed a normal diet.

The authors point out that current treatment for inflammatory liver disease involves ursodeoxycholic acid, the long term effects of which remain unclear. The other alternative is a liver transplant.

Curcumin is a natural product, they say, which seems to target several different parts of the inflammatory process, and as such, may therefore offer a very promising treatment in the future.

 

Source: Anna Baghdasaryan, Thierry Claudel, Astrid Kosters, Judith Gumhold, Dagmar Silbert, Andrea Thüringer, Katharina Leski, Peter Fickert, Saul J Karpen, Michael Trauner. Curcumin improves sclerosing cholangitis in Mdr2-/- mice by inhibition of cholangiocyte inflammatory response and portal myofibroblast proliferation. Gut, 2010; 59: 521-530

More

Protect Against Kidney Stones

Print pagePDF pageEmail page

Kidney stones are small, hard deposits of minerals and salts that can form in the kidneys when urine becomes concentrated. Specific treatment beyond increasing water intake is usually not needed, but a kidney stone can be very painful to pass, as anyone who has had one can tell you. While anyone can get kidney stones, there are multiple risk factors that can potentially increase your chances of acquiring them, including:

  • Family history of kidney stones.
  • Being over 40 years old.
  • Being male.
  • Dehydration.
  • High protein, high sodium and high sugar diets.
  • Being obese.
  • Digestive diseases such as inflammatory bowel disease or surgeries such as gastric bypass.

You can reduce your risk of getting kidney stones by:

  • Drinking water throughout the day. For those with a history of kidney stones, doctors usually recommend passing approximately 2.5 litres of urine daily. In summer months you need to consume considerably more fluids to stay well-hydrated.
  • Eating fewer foods containing high amounts of oxalate. Kidney stones can form due to a build up of calcium oxalate. Foods rich in oxalate include spinach, beets, rhubarb, okra, tea, chocolate and soy products.
  • Limiting salt and animal protein in your diet. Reduce the amount of salt in your diet and choose non-animal protein sources such as nuts to reduce your chances of getting kidney stones.
  • Watching out for stealth sources of sodium. Some energy and sports drinks contain high levels of sodium and/or caffeine. While they may quench your thirst, you may also be increasing your risk of stone formation.
  • Re-hydrating often if engaged in strenuous activity if you have long-term exposure to the heat. Painters, roofers, landscapers, marathon runners and people who enjoy outdoor sports activities that last several hours at a time need to pay special attention to their water intake and watch for signs of dehydration. Health experts recommend at least 16 to 32 ounces of water per hour of heat exposure. A lack of sweat or urination, dizziness, weakness, headache, muscle cramps, nausea or vomiting are possible signs of heat-related illness or dehydration.
  • Avoiding calcium supplements, but calcium-rich foods are OK. Calcium in the food you eat does not increase your risk of getting kidney stones. Keep eating calcium-rich foods unless your doctor advises you otherwise. However, calcium supplements have been linked to higher risk of kidney stones. Consult your physician before starting a calcium supplement.

A dietitian like Nastaran can help those at risk to plan meals that will reduce the chance of getting kidney stones.

More

Vitamin E May Decrease Pulmonary Disease

Print pagePDF pageEmail page

Ms. Agler and colleagues reviewed data compiled by the Women's Health Study, a multi-year, long-term effort ending in 2004 that focused on the effects of aspirin and vitamin E in the prevention of cardiovascular disease and cancer in nearly 40,000 women aged 45 years and older. Study participants were randomized to receive either 600 mg of vitamin E or a placebo every other day during the course of the research.

Although fewer women taking vitamin E developed COPD, Ms. Agler noted the supplements appeared to have no effect on asthma, and women taking vitamin E supplements were diagnosed with asthma at about the same rate as women taking placebo pills. Importantly, Ms. Agler noted the decreased risk of COPD in women who were given vitamin E was the same for smokers as for non-smokers.

Ms. Agler said further research will explore the way vitamin E affects the lung tissue and function, and will assess the effects of vitamin E supplements on lung diseases in men. “If results of this study are borne out by further research, clinicians may recommend that women take vitamin E supplements to prevent COPD,” Ms. Agler noted. “Remember that vitamin E supplements are known to have detrimental effects in some people; for example vitamin E supplementation increased risk of congestive heart failure in cardiovascular disease patients. Broader recommendations would need to balance both benefits and risks. “

More

Omega 3s Show Health Benefits for Non-Fish Eaters

Print pagePDF pageEmail page

Increased intakes of omega-3 fatty acids may decrease the risk of heart disease and heart attack in people with low fish intakes, says a new study from The Netherlands. Daily intakes of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) of about 240 milligrams was associated with a 50 per cent reduction in the risk of coronary heart disease (CHD), compared with intakes of about 40 milligrams, according to findings published in the Journal of Nutrition. Furthermore, the highest average intake of DHA and EPA was associated with a 38 per cent reduction in the heart attack, said researchers from Wageningen University following a study with over 21,000 people with low fish intakes.

The heart health benefits of consuming oily fish, and the omega-3 fatty acids they contain, are well-documented, being first reported in the early 1970s by Jorn Dyerberg and his co-workers in The Lancet and The American Journal of Clinical Nutrition. To date, the polyunsaturated fatty acids (PUFAs) have been linked to improvements in blood lipid levels, a reduced tendency of thrombosis, blood pressure and heart rate improvements, and improved vascular function.

Omega-3 fatty acids, most notably DHA and EPA, have been linked to a wide-range of health benefits, including reduced risk of cardiovascular disease (CVD) and certain cancers, good development of a baby during pregnancy, joint health, and improved behaviour and mood.

Study details

Intakes of EPA plus DHA, and fish were assessed in 21,342 people aged between 20 and 65. Fish intakes ranged from 1.1 to 17.3 grams per day. Over the course of an average of 11.3 years, the researchers documented 647 deaths, of which 82 were linked to coronary heart disease, with 64 of these being heart attack.

According to the results, the highest average intake of EPA plus DHA (234 milligrams per day) was associated with a 51 per cent reduction in the risk of fatal CHD, compared to the lowest average intake (40 mg per day).

“In conclusion, in populations with a low fish consumption, EPA+DHA and fish may lower fatal CHD and [heart attack] risk in a dose-responsive manner,” wrote the researchers.

Source: Journal of Nutrition
“Marine (n-3) Fatty Acids, Fish Consumption, and the 10-Year Risk of Fatal and Nonfatal Coronary Heart Disease in a Large Population of Dutch Adults with a Low Fish Intake”
Authors: J. de Goede, J.M. Geleijnse, J.M. A. Boer, D. Kromhout, W. M.M. Verschuren

More