Meta-Analyses Link Rosiglitazone to Increased Cardiovascular Risk

In continuation of my update on Rosiglitazone

Rosiglitazone seems to be associated with an increased cardiovascular risk, particularly heart failure, according to data from a systematic review and meta-analyses published online Feb. 5 in The BMJ.

Joshua D. Wallach, Ph.D., from the Yale School of Public Health in New Haven, Connecticut, and colleagues conducted a systematic review and individual patient-level data (IPD) and summary-level meta-analyses of randomized, controlled, phase II to IV clinical trials that compared rosiglitazone to any control in adults. Data were included from 33 eligible trials for which IPD were available (21,156 patients). Data from 103 trials for which IPD were not available were included in the meta-analyses for myocardial infarction and cardiovascular-related death (23,683 and 22,772 patients, respectively).

The researchers found that when analyses were limited to trials with IPD and trials with zero events in only one arm were accounted for, the risk for the composite outcome (acute myocardial infarction, heart failure, cardiovascular-related death, and non-cardiovascular-related death) was increased for rosiglitazone-treated patients versus controls (odds ratio, 1.33; 95 percent confidence interval, 1.09 to 1.61). The odds ratios were 1.17 (0.92 to 1.51) for myocardial infarction, 1.54 (1.14 to 2.09) for heart failure, 1.15 (0.55 to 2.41) for cardiovascular-related death, and 1.18 (0.60 to 2.30) for non-cardiovascular-related death. The odds ratios for myocardial infarction and cardiovascular-related death were attenuated for analyses including trials for which IPD were not available.

"This finding suggests that IPD might be necessary to accurately classify all adverse events when performing meta-analyses focused on safety," the authors write.

Several authors disclosed financial ties to the pharmaceutical, medical device, legal, and medical technology industries.

https://www.bmj.com/content/368/bmj.l7078

https://en.wikipedia.org/wiki/Rosiglitazone

Diabetes drug rosiglitazone can reduce development of neuropathic pain..

In continuation of my update on Rosiglitazone,

The diabetes drug rosiglitazone (Avandia) can control inflammation leading to nerve damage and abnormal pain responses,  claims the researchers of  Juntendo University School of Medicine, Tokyo.

As per the claim by the researchers, Rosiglitazone works by blocking a specific pathway—called PPAR-gamma—which appears to play a critical role in the development of disabling neuropathic pain. Researchers  therefore propose PPAR-gamma regulation of the macrophage-mediated inflammatory response as a novel therapeutic target for treating neuropathic pain development.

More...

Diabetes drug rosiglitazone, improves memory, study suggests

In continuation of my update on rosiglitazone 

Working with genetically engineered mice designed to serve as models for Alzheimer's, University of Texas Medical Branch at Galveston researchers found that treatment with the anti-insulin-resistance drug rosiglitazone enhanced learning and memory as well as normalized insulin resistance. The scientists believe that the drug produced the response by reducing the negative influence of Alzheimer's on the behavior of a key brain-signaling molecule.

"Using this drug appears to restore the neuronal signaling required for proper cognitive function," said UTMB professor Larry Denner, the lead author of a paper describing this work now online in the Journal of Neuroscience. "It gives us an opportunity to test several FDA-approved drugs to normalize insulin resistance in Alzheimer's patients and possibly also enhance memory, and it also gives us a remarkable tool to use in animal models to understand the molecular mechanisms that underlie cognitive issues in Alzheimer's."

Ref : http://www.utmb.edu/newsroom/article8071.aspx

Diabetes drug improves memory, study suggests

Pungent Ingredient, piperine, in Black Pepper Targets Fat Cells

A preliminary new study suggests that the pungent component in black pepper known as piperine fights fat by blocking the formation of new fat cells.

If further studies confirm these effects, researchers say black pepper may offer a natural alternative for the treatment of fat-related disorders like obesity.

"Our findings suggest that piperine (see above structure), a major component of black pepper, inhibits fat cell differentiation ... thus leading to its potential use in the treatment of obesity-related diseases," writes researcher Ui-Hyun Park of Sejong University in Seoul, Korea 

Black Pepper the Fat Fighter....

Researchers say the benefits of black pepper and the black pepper plant have been known for centuries in traditional Eastern medicine, in which it is used to treat cholera, diarrhea, and other gastrointestinal issues.

In their study, researchers looked at the effects of piperine on gene expression in fat tissue in the lab and in computer models.

The results showed that piperine interfered with the activity of genes responsible for forming new fat cells.

Researchers say this benefit of black pepper sets up a chain reaction that helps keep the formation of fat in check in other ways as well.

"Overall, our results suggest that piperine could be a lead natural compound for the treatment of fat-related disorders," the researchers write.

2 Drugs Better Than 1 to Treat Youth With Type 2 Diabetes

2 Drugs Better Than 1 to Treat Youth With Type 2 Diabetes: A combination of two diabetes drugs, metformin and rosiglitazone, was more effective in treating youth with recent-onset type 2 diabetes than metformin alone, a study funded by the National Institutes of Health (NIH) has found. Adding an intensive lifestyle intervention to metformin provided no more benefit than metformin therapy alone.

The study also found that metformin therapy alone was not an effective treatment for many of these youth. In fact, metformin had a much higher failure rate in study participants than has been reported in studies of adults treated with metformin alone.

The study found that treatment with metformin alone was inadequate for maintaining acceptable, long-term, blood glucose control in 51.7 percent of youth over an average follow-up of 46 months. The failure rate was 38.6 percent in the metformin and rosiglitazone group, a 25.3 percent reduction from metformin alone. In the metformin plus lifestyle group the failure rate was 46.6 percent.

Two drugs better than one to treat youth with type 2 diabetes, study suggests

Two drugs better than one to treat youth with type 2 diabetes, study suggests: A combination of two diabetes drugs, metformin and rosiglitazone, was more effective in treating youth with recent-onset type 2 diabetes than metformin alone, a new study has found. Adding an intensive lifestyle intervention to metformin provided no more benefit than metformin therapy alone.

Metformin more effective than sulfonylurea in controlling type 2 diabetes

In continuation of my update on Metformin

A Vanderbilt study examining the impact of the two most commonly prescribed oraldiabetes medications on the risk for heart attack, stroke and death has found the drug metformin has benefits over sulfonylurea drugs.

It was important to examine the cardiovascular impact of the more commonly used diabetes drugs after recent controversy surrounded another diabetes medication, rosiglitazone, because it was associated with an increased cardiac risk, said lead author, Christianne L. Roumie, M.D., MPH, assistant professor of Internal Medicine and Pediatrics. Smaller studies pointed to a potential advantage of taking the drug metformin but this study confirms this in a large population.

"We demonstrated that for every 1,000 patients who are using metformin for a year there are two fewer heart attacks, strokes or deaths compared with patients who use sulfonylureas. I think this reinforces the recommendation that metformin should be used as the first medication to treat diabetes," Roumie said.

The researchers looked at the charts of more than 250,000 veterans receiving care in Veterans Health Administration hospitals throughout the United States.

More...

Metformin more effective than sulfonylurea in controlling type 2 diabetes

Investigational diabetes drug appears to improve insulin sensitivity without side effects

Drugs for type 2 diabetes can contribute to weight gain, bone fractures and cardiovascular problems, but in mice, an investigational drug appears to improve insulin sensitivity without those troublesome side effects, researchers at Washington University School of Medicine in St. Louis have shown.

"Current diabetes medications activate a receptor that improves insulin sensitivity, but unfortunately also contributes to side effects that make some people discontinue the medication, contributing to other health problems," says principal investigator Brian N. Finck, PhD. "So even though these drugs are effective, we'd really like to find new insulin-sensitizing therapies that would avoid activating the same receptor."

Finck, a research assistant professor of medicine in the Division of Geriatrics and Nutritional Science, worked with colleagues at the University of Michigan and at the drug discovery company Metabolic Solutions Development Co., LLC. The scientists studied one of the company's investigational drugs, MSD-0602, focusing on its effects in obese mice.

The drug improved blood glucose levels and insulin tolerance in the mice, as did the two diabetes drugs that already are on the market: rosiglitazone (Avandia) and pioglitazone (Actos). All three medications appeared to be about equally effective, but MSD-0602 didn't bind to and activate a receptor in cells called PPARγ. Rather, the investigational drug clings to the mitochondria, part of the cell that produces energy.

"The drug altered the cell's ability to generate energy," Finck says. "And it also seems to have an anti-inflammatory role in the cell. We also found that the drug improved insulin sensitivity in many different kinds of cells including muscle, fat and liver cells."

 Next, he and his colleagues will attempt to identify proteins that bind to the mitochondrial membrane. Future therapies then could be developed specifically to bind to those proteins while avoiding activation of the PPARγ pathway.

Investigational diabetes drug appears to improve insulin sensitivity without side effects: Drugs for type 2 diabetes can contribute to weight gain, bone fractures and cardiovascular problems, but in mice, an investigational drug appears to improve insulin sensitivity without those troublesome side effects, researchers at Washington University School of Medicine in St. Louis have shown.

Ref : http://www.jbc.org/content/early/2012/05/23/jbc.M112.363960.full.pdf

Diabetes drug found no better than placebo at treating nonalcoholic fatty liver disease: But randomized, double-blind clinical trial suggests better way to conduct future trials

A diabetes medication described in some studies as an effective treatment for nonalcoholic fatty liver disease (NAFLD) works no better than a placebo, report researchers at University of California San Diego School of Medicine, after conducting the first randomized, double-blind, controlled clinical trial of sitagliptin, an oral antihyperglycemic marketed by Merck & Co. under the name Januvia.

 

Januvia (sitagliptin)

Writing in the Journal of Hepatology, a multidisciplinary team headed by study senior author Rohit Loomba, MD, professor of medicine in the Division of Gastroenterology and director of the NAFLD Translational Research Unit at UC San Diego School of Medicine, found that sitagliptin was not significantly better than a placebo in reducing liver fat, as measured by magnetic resonance imaging-proton density fat fraction (MRI-PDFF) and other technologies.

The team included Claude Sirlin, MD, professor and vice chair (translational research) of radiology at UC San Diego School of Medicine, and Richard Ehman, MD, professor of radiology at Mayo Clinic. The labs, led by Sirlin and Ehman, invented and validated the advanced noninvasive imaging techniques applied in this study.

NAFLD is the accumulation of fat in the livers of people who drink little or no alcohol. It is the leading cause of chronic liver disease in the United States. Roughly one-quarter of Americans -- an estimated 100 million adults and children -- have NAFLD, which can progress to a more serious form called nonalcoholic steatohepatitis, which in turn can develop into cirrhosis, liver cancer and liver failure.

Currently, there are no approved, specific therapies for NAFLD. However, it is commonly associated with diabetes, which has prompted researchers to test diabetes medications, such as metformin, rosiglitazone and liraglutide, as potential treatments.

Sitagliptin is another possibility. In clinical trials conducted in patients with type 2 diabetes, sitagliptin has been shown to be effective in improving glycemic (blood sugar) control, cholesterol, lipoproteins and other health measures compared to placebo.

"But human trials of sitagliptin have been limited to date because they have lacked important tools like a placebo arm and allocation concealment (in which researchers do not know what the next treatment allocation will be, further preventing selection bias in testing)," said Loomba.

In the new study, 50 NAFLD patients with pre-diabetes or early diabetes were randomized into two groups: one received a 100 milligram oral dose of sitagliptin daily for 24 weeks, the other received a placebo. Primary outcome was assessed by changes to liver fat measured by MRI-PDFF, conducted by the Liver Imaging Group in the Department of Radiology at UC San Diego Health.

At end-of-treatment, Loomba and colleagues found no significant differences between sitagliptin and placebo across a range of measures. Neither study group experienced any adverse effects.

While the study did not support earlier findings that sitagliptin was an effective treatment for NAFLD, Loomba said it provided new evidence that clinical trials with patients at higher risk of diabetes do not necessarily need a liver biopsy to be efficiently screened for potential therapeutic agents.

"Biopsies present their own complications, such as possible pain and infection," said Loomba. "MRI-PDFF, and magnetic resonance elastography (a non-invasive imaging technique that measures the stiffness of soft tissues) proved to be accurate, quantitative, and useful over the study duration in measuring the state and progression of disease. These technologies should be further investigated in clinical trials, especially those of longer duration."

Encouraging results from first phase III clinical trials of Balaglitazone (an anti-diabetic drug)......

Balaglitazone (CAS-199113-98-9),5-[[4-[3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl] methoxy]phenyl-methyl]thiazolidine-2,4-dione, (see structure) is a novel partial agonist of PPAR-gamma, which elicits only 52% of the PPAR-gamma activation observed with both pio- and rosiglitazone.

            

Pre-clinical studies have indicated that besides robust glucose lowering ability, balaglitazone results in lower body fluid accumulation, lower fat accumulation, less heart enlargement and no reduction of bone formation, indicating that Balaglitazone may be able to displace the balance between desired and side effects, and thus show a better safety profile than full agonists of PPAR-gamma.

 Now Reddy's Lab, has come up with interesting results from its  Phase III clinical trial programme.The study explored the impact of adding placebo, Balaglitazone 10mg, Balaglitazone 20mg or Pioglitazone 45mg to a background treatment regimen of stable insulin therapy for a period of 26 weeks. The primary endpoint was HbA1c reduction, while several secondary endpoints including fasting plasma glucose, oedema, weight gain, and body composition were considered.

In all, 409 patients were randomized in roughly equal proportions across the four arms of the study. All three active arms (Balaglitazone 10mg, 20mg and Pioglitazone 45mg) showed similar levels of efficacy with respect to both HbA1c and fasting plasma glucose.

All three active arms showed good tolerability and adverse event profile, with Balaglitazone 10mg demonstrating less water retention, less fat accumulation, lower weight/BMI gain and less bone loss when compared to the Pioglitazone arm.

Encourged by these results both companies (Dr. Reddy's & Rheoscience) are planning for detailed studies required for registration of  Balaglitazone.

Type 2 diabetes is a major cause of morbidity and mortality in the industrialized world, with cardiovascular disease as the leading cause of death, accounting for almost 50% of all T2D deaths. Furthermore, the number of T2D patients is increasing rapidly, and the number of patients is expected to reach between 300 and 380 million by 2025, thereby placing an enormous economical burden on global healthcare. Hope new drugs will take care of this problem.



Ref : http://www.drreddys.com/media/popups/jan4_2010.html

Naringenin (grape fruits) initiates increased fatty acid oxidation, inhibits vLDL production...

Naringenin is a flavonoid that is considered to have a bioactive effect on human health as antioxidant, free radical scavenger, anti-inflammatory, carbohydrate metabolism promoter, and immune system modulator. It is the predominant flavanone in grapefruit. It  has been shown to have an inhibitory effect on the human cytochrome P450 isoform CYP1A2, which can change pharmacokinetics in a human (or orthologous) host of several popular drugs in an adverse manner, even resulting in carcinogens of otherwise harmless substances. Naringenin has also been shown to reduce hepatitis C virus production by infected hepatocytes (liver cells) in cell culture. This seem to be secondary to Naringenin ability to inhibit the secretion of very-low-density lipoprotein by the cells.It has been reported that Naringenin,  lowers the plasma and hepatic cholesterol concentrations by suppressing HMG-CoA reductase and ACAT in rats fed a high-cholesterol diet. 

Now interestingly, researchers from Hebrew University of Jerusalem and Massachusetts General Hospital (MGH) report that naringenin activates a family of small proteins, called nuclear receptors, causing the liver to break down fatty acids. In fact, the compound seems to mimic the actions of other drugs, such as the lipid-lowering Fenofibrate and the anti-diabetic Rosiglitazone, offering the advantages of both. If the results of this study extend to human patients, this dietary supplement could become a staple in the treatment of hyperlipidemia, type-2 diabetes, and perhaps metabolic syndrome.

The researchers demonstrated that the compound activates PPARα and PPARγ by dramatically increasing the levels of a co-activator peptide of both, called PGC1α. At the same time, naringenin bound directly to LXRα, blocking its activation. These effects culminated with increased fatty acid oxidation and the inhibition of vLDL ('bad cholesterol') production.  

"It is a fascinating find," says Yaakov Nahmias, PhD, of the Hebrew University of Jerusalem the paper's senior author. "We show the mechanism by which naringenin increases two important pharmaceutical targets, PPARα and PPARγ, while blocking a third, LXRα. The results are similar to those induced by long periods of fasting".

Authors claim that, it is a process which is similar to the Atkins diet, without many of the side effects and the liver behaves as if fasting, breaking down fatty acids instead of carbohydrates. 

"Dual PPARα and PPARγ agonists, like naringenin, were long sought after by the pharmaceutical industry," says Nahmias, "but their development was plagued by safety concerns. Remarkably, naringenin is a dietary supplement with a clear safety record. Evidence suggests it might actually protect the liver from damage."....

 Ref : http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0012399

Two-Drug Therapy Helped Kids With Type 2 Diabetes

Two-Drug Therapy Helped Kids With Type 2 Diabetes:  Children with type 2 diabetes may achieve better blood sugar control with a combination of two drugs, metformin and Avandia, than with metformin alone, a new study suggests. However, Avandia (rosiglitazone) was recently linked...