Thursday, April 4, 2013

New class of anti-malarial compounds discovered


A group of researchers from 16 institutions around the world has identified a new class of anti-malarial compounds that target multiple stages of the malaria parasite's life cycle  These compounds could potentially be developed into drugs that treat and prevent malaria infection. Known as 4-(1H)-quinolone-3-diarylethers, the candidate anti-malarials are derived from a compound called endochin that effectively treats malaria in birds. When tested in the laboratory and in mice, the compounds demonstrated strong activity againstPlasmodium falciparum and Plasmodium vivax, the two parasites that cause most human cases of malaria. Transmitted via a mosquito bite, malaria causes cycles of chills, fever and fatigue, and is responsible for roughly 660,000 deaths per year, according to the World Health Organization. New drugs are needed because of the emergence of malaria-inducing parasites that are resistant to existing medications.

Of the 4-(1H)-quinolones, the researchers focused their efforts on the compound ELQ-300, which inhibited malaria parasites during the erythrocytic stage, when they cause symptoms in humans; as well as during the gametocyte and developmental stages in the mosquito, when the parasites are transmitted. In addition, when ELQ-300 was administered to mice infected with the Plasmodium species that cause malaria in mice, the infection was cured. The study results also suggested that the compound could be adapted into a once-daily dose in humans and would be slow to engender resistance. The researchers are currently proceeding with preclinical development of ELQ-300 (see the structure below).

Ref :1.  http://www.niaid.nih.gov/news/newsreleases/2013/Pages/ELQ300.aspx
2. http://stm.sciencemag.org/content/5/177/177ra37.short?rss=1




New class of anti-malarial compounds discovered

Tuesday, April 2, 2013

Drug treatment corrects autism symptoms in mouse model

The researchers tested suramin,  a well-known inhibitor of purinergic signaling used medically for the treatment of African sleeping sickness since shortly after it was synthesized in 1916 -- in mice. They found that this APT mediator corrected autism-like symptoms in the animal model, even if the treatment was started well after the onset of symptoms. The drug restored 17 types of multi-symptom abnormalities including normalizing brain synapse structure, cell-to-cell signaling, social behavior, motor coordination and normalizing mitochondrial metabolism.



"The striking effectiveness shown in this study using APT to 'reprogram' the cell danger response and reduce inflammation showcases an opportunity to develop a completely new class of anti-inflammatory drugs to treat autism and several other disorders," Naviaux said.

Ref : http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0057380


 Drug treatment corrects autism symptoms in mouse model

Monday, April 1, 2013

Disinfectant mouthwashes may be effective against cancers of the mouth and throat

Patients who suffer from gingivitis are often advised to use disinfectant mouthwashes. In the future, the active ingredients in these products could be used in a completely different area. Chlorhexidin and Alexidin increase programmed cell death and may be effective against cancers of the mouth and throat.

Berg and his co-workers were successful: Chlorhexidin (below left structure), the active component in commercial oral disinfectants such as Chlorhexamed, Chlorhexal, Periogard, Corsodyl, and Chlorohex; as well as Alexidin (below right structure), the active component in Esemdent, both inhibit the binding of the apoptosis inhibitor to the apoptosis trigger. Chlorhexidin's effect is specific, while Alexidin has additional very weak effects on other proteins.

Why are apoptosis proteins interesting? Apoptosis is decreased in tumor cells, so the cells do not die off and continue to divide. One reason for this is that they produce too much of the apoptosis-inhibiting protein. In experiments with cultures of cells from various tongue and throat carcinomas, both compounds caused increased apoptosis. This effect is much stronger in the cancer cells than in healthy cells. It may be possible to use these drugs in therapeutic applications.

The researchers hope to find other protein-protein interactions that could be targeted with approved small-molecule drugs....


http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1521-3773/homepage/press/201311press.html


Disinfectant mouthwashes may be effective against cancers of the mouth and throat

Saturday, March 30, 2013

Japanese P2 study shows potential of combined vaccine and steroid drug in castration resistant PCa

 In continuation of my update on dexamethasone

Multi-peptide vaccination therapy combined with the low-dose steroid drug dexamethasone shows promise in treating chemotherapy-naive castration resistant prostate cancer (CRPC) patients.

Friday, March 29, 2013

New drugs may improve quality of life for people with Parkinson's disease


In the study, 225 people were randomized to receive either eight weeks of stable dose treatment with a placebo or the drug droxidopa, (see structure)  

 
which converts to norepinephrine. After one week of stable treatment, those who received the drug had a clinically meaningful, two-fold decrease in the symptoms of dizziness and lightheadedness, when compared to placebo. They also had fewer falls, or 0.38 falls per patient per week, compared to 1.73 for those receiving a placebo on average over the entire 10-week study duration.

The second study looked at treatment with a new drug for "wearing-off" that occurs with people who have been taking levodopa for several years. As each dose wears off, people experience longer periods of time where the motor symptoms do not respond to levodopa. For the study, 420 people who were experiencing an average of six hours of "off" time per day received a placebo or one of four dosages of the drug tozadenant in addition to their levodopa for 12 weeks. People receiving two of the dosages of the drug had slightly more than an hour less off time per day at the end of 12 weeks than they had at the start of the study. They also did not have more troublesome involuntary movements during their "on" time, called dyskinesia, that can occur. 
 
The third study looked at 321 people with early Parkinson's disease whose symptoms were not well-controlled by a dopamine agonist drug. For the 18-week study, the participants took either the drug rasagiline or a placebo in addition to their dopamine agonist. At the end of the study, those taking rasagiline had improved by 2.4 points on a Parkinson's disease rating scale. In addition, rasagiline was well tolerated with adverse events similar to placebo.

Wednesday, March 27, 2013

Breakthrough in battle against leukemia


The research team has demonstrated that leukaemic cells can be eradicated by removing a carbohydrate modification displayed on the cell's surface.


Director of Griffith University's Institute for Glycomics, Professor Mark von Itzstein is the Australian team leader. He said the discovery is an important advance against leukemia, a cancer of malignant white blood cells that multiply uncontrollably. Acute lymphoblastic leukemia (ALL) is the most common childhood cancer.


"We have found that the leukaemic cell has an altered cell surface carbohydrate decoration compared to normal cells and this also conveys resistance to drug treatment," Professor von Itzstein said.


"We have now shown that with the removal of this carbohydrate alteration the cells die."

Professors Nora Heisterkamp and John Groffen, leaders of the US-based team, Professor von Itzstein and their colleagues have published their research findings in the latest edition of the Journal of Experimental Medicine.


Professor von Itzstein said the research could lead to new ways to fight the disease, particularly where it has become treatment resistant.


"Up until 40 years ago, only one child in five survived ALL," but advances in chemotherapy have changed that outcome and now nearly 80 percent of children with ALL will be cured," Professor von Itzstein said.


"For the remaining 20 percent, however, the disease returns necessitating additional rounds of intensive chemotherapy. Unfortunately, most relapsed patients die within one year because their cancer cells are resistant to chemotherapy.

Monday, March 25, 2013

Drug may improve outcomes after heart attack


 We know that, Eplerenone (INN)  is an aldosterone antagonist used as an adjunct in the management of chronic heart failure. It is similar to the diuretic spironolactone, though it is much more selective for the mineralocorticoid receptor in comparison (i.e., does not possess any antiandrogen, progestogen, or estrogenic effects), and is specifically marketed for reducing cardiovascular risk in patients following myocardial infarction. It is marketed by Pfizer under the trade name Inspra. Eplerenone is a potassium-sparing diuretic, meaning that it helps the body get rid of water but still keep potassium....

Now,

The REMINDER (Reduction of heart failure morbidity in patients with acute ST-elevation myocardial infarction) trial was a randomized, double-blind trial of 1,012 patients who had a heart attack caused by a complete blockage of one of the heart's arteries. Patients had no signs or history of heart failure. They were given either eplerenone or placebo in addition to standard therapy. Overall, patients taking eplerenone were 38 percent less likely to have poor outcomes than those given a placebo.


Eplerenone counteracts a hormone called aldosterone, which can increase blood pressure. The drug is currently approved to treat hypertension and as a treatment for patients who have heart failure several days after a heart attack.


"This is the first randomized trial to test a mineralocorticoid receptor agonist during the acute phase of heart attack, and the results suggest a clinical benefit," said Gilles Montalescot, MD, PhD, lead investigator of the study and professor of cardiology and head of the Cardiac Care Unit at Pitié-Salpétrière Hospital, Paris.


About 5.8 million Americans have heart failure, a condition in which the heart cannot pump enough blood to meet the body's oxygen and energy needs. Improvements in heart attack treatment have increased chances of survival, but damage after heart attack is one risk factor for heart failure. Clinical trials and registries show that in the 30 days after a first heart attack, between 8.6 percent and 40 percent of patients will be diagnosed with heart failure.


Sunday, March 24, 2013

Clot-busting drug as effective as angioplasty, study suggests

 A clot-busting therapy may benefit some heart attack patients who cannot have immediate angioplasty, according to research presented today at the American College of Cardiology's 62nd Annual Scientific Session.


Saturday, March 23, 2013

Promising new drug treats and protects against radiotherapy-associated oral mucositis

Mouse model studies show that administered genetically or topically, protein Smad7 protects against or heals mouth sores commonly associated with cancer treatment.

Ref : http://www.nature.com/nm/journal/vaop/ncurrent/full/nm.3118.html

Friday, March 22, 2013

Bitter melon juice prevents pancreatic cancer in mouse models

"Three years ago researchers showed the effect of bitter melon extract on breast cancer cells only in a Petri dish. This study goes much, much farther. We used the juice  people especially in Asian countries are already consuming it in quantity. We show that it affects the glucose metabolism pathway to restrict energy and kill pancreatic cancer cells," says Rajesh Agarwal, PhD, co-program leader of Cancer Prevention and Control at the CU Cancer Center and professor at the Skaggs School of Pharmacy and Pharmaceutical Sciences.


Agarwal's interest came from connecting the dots of existing research in a novel way. Diabetes tends to presage pancreatic cancer and bitter melon has been shown to effect type-II diabetes, and has been used for centuries against diabetes in the folk medicines of China and India. Following this line of thinking, Agarwal and colleagues wondered what would happen if they closed out the middle man of diabetes and directly explored the link between bitter melon and pancreatic cancer.


The result, Agarwal says, is, "Alteration in metabolic events in pancreatic cancer cells and an activation of the AMP-activated protein kinase, an enzyme that indicates low energy levels in the cells."


Perhaps not coincidentally, bitter melon also regulates insulin secretion by pancreatic beta cells. After studies in cell cultures, the group showed that mouse models of pancreatic cancer that were fed bitter melon juice were 60 percent less likely to develop the disease than controls.


"It's a very exciting finding," Agarwal says. "Many researchers are engineering new drugs to target cancer cells' ability to supply themselves with energy, and here we have a naturally-occurring compound that may do just that."


The Agarwal Lab is now applying for grants that will allow them to move the study of bitter melon into further chemoprevention trials in mouse models of pancreatic cancer.

Ref : dx.doi.org/10.1093/carcin/bgt081

 

Monday, March 18, 2013

New Drugs May Offer Hope to Parkinson's Patients - Drugs.com MedNews


"Progress is being made to expand our use of medications, develop new medications and to treat symptoms that either we haven't been able to treat effectively or we didn't realize were problems for patients," said Dr. Robert Hauser, professor of neurology and director of the University of South Florida Parkinson's Disease and Movement Disorders Center in Tampa.
Parkinson's disease, a degenerative brain disorder, affects more than 1 million Americans. It destroys nerve cells in the brain that make dopamine, which helps control muscle movement. Patients experience shaking or tremors, slowness of movement, balance problems and a stiffness or rigidity in arms and legs.
In one study, Hauser evaluated the drug droxidopa (see the structure right),  which is not yet approved for use in the United States, to help patients who experience a rapid fall in blood pressure when they stand up, which causes light-headedness and dizziness. About one-fifth of Parkinson's patients have this problem, which is due to a failure of the autonomic nervous system to release enough of the hormone norepinephrine when posture changes.
Hauser studied 225 people with this blood-pressure problem, assigning half to a placebo group and half to take droxidopa for 10 weeks. The drug changes into norepinephrine in the body.
Those on the medicine had a two-fold decline in dizziness and lightheadedness compared to the placebo group. They had fewer falls, too, although it was not a statistically significant decline.
In a second study, Hauser assessed 420 patients who experienced a daily "wearing off" of the Parkinson's medicine levodopa (see structure left), during which their symptoms didn't respond to the drug. He compared those who took different doses of a new drug called tozadenant, which is not yet approved, with those who took a placebo. All still took the levodopa.
At the start of the study, the patients had an average of six hours of "off time" a day when symptoms reappeared. After 12 weeks, those on a 120-milligram or 180-milligram dose of tozadenant (see structure below) had about an hour less of "off time" each day than they had at the start of the study.
Tozadenant, which works on brain receptors thought to regulate motor function, merits further study in future trials, Hauser said.
In another study, Hauser looked at 321 patients with early stage Parkinson's whose symptoms weren't handled well by a medicine called a dopamine agonist, typically the first drug prescribed for Parkinson's patients. During the 18-week study, Hauser assigned them to take either their usual medicine plus an add-on drug called rasagiline (brand name Azilect see below structure) or their usual medicine and a placebo.
Azilect is approved for use in patients with early stage disease as a single therapy or as an add-on to levodopa, Hauser said, but not yet as an add-on to dopamine agonists.
Those taking the Azilect   but not those taking the placebo   improved by 2.4 points on a standard Parkinson's disease rating scale.
Costs of the still unapproved drugs are not known. Azilect costs about $200 monthly at the 1-milligram daily dose used in the study.
Each of the studies was funded by the pharmaceutical company making the particular drug: Chelsea Therapeutics paid for the blood-pressure study; Biotie Therapies Inc., supported the "wearing-off" study; and Teva Pharmaceutical Industries sponsored the Azilect study. Hauser is a consultant for all three companies.


Friday, March 15, 2013

Can Green Tea, Coffee Reduce Stroke Risk? - Drugs.com MedNews

In continuation of my update on green tea...


This study of about 83,000 people suggests that drinking green tea or coffee daily might lower stroke risk by about 20 percent, with even more protection against a specific type of stroke.
"The regular action of daily drinking [of] green tea and coffee is a benefit in preventing stroke," said lead researcher Dr. Yoshihiro Kokubo, chief doctor in the department of preventive cardiology at the National Cerebral and Cardiovascular Center, in Osaka.
"If you cannot readily improve your lifestyle, try to prevent stroke by drinking green tea every day," he said.
Although it isn't certain why coffee and tea may have this effect, Kokubo thinks it might be due to certain properties in these drinks that keep blood from clotting.
In addition, green tea contains catechins, which have an antioxidant, anti-inflammatory effect. Some chemicals in coffee, such as chlorogenic acid, may cut the risk of stroke by lowering the chances of developing type 2 diabetes, he explained.
Coffee also contains caffeine, which may have an impact on cholesterol levels and blood pressure, and may cause changes in insulin sensitivity, which affects blood sugar, he added.
One expert, Dr. Ralph Sacco, past president of the American Heart Association, cautioned that this type of study cannot say for sure that the lower risk of stroke is really the result of drinking coffee or tea.
"Such association studies are still limited in [the] ability to tell whether it is some ingredients in the coffee or tea or some other behavior common to coffee and tea drinkers that is driving the protective effects," said Sacco, chairman of neurology at the University of Miami Miller School of Medicine.


Wednesday, March 6, 2013

Grape seed and skin extract: A weapon in the fight against kidney disease caused by high-fat diets


Researchers examined the effect of GSSE processed from a grape cultivar ('Carignan') of Vitis vinifera from northern Tunisia on rats. Rats were fed a high-fat diet that induced a low-grade reno-lipotoxicity, that is, kidney damage associated with lipids. This was characterized by elevations in plasma urea and protein in the urine. The researchers found increased deposits of triglycerides (TG) (especially saturated fatty acids), increased signs of oxidative stress and depleted copper levels in the kidneys. There was also histological evidence of disturbance in the kidney structure. When the animals received GSSE at 500 mg/kg bw (which corresponds to 35g/day for a 70 kg human adult) along with the high-fat diet there was a partial reversal of the TG deposition as well as the histological damage. The authors suggest polyphenols including resveratrol are likely the components in GSSE responsible for the positive effects. Furthermore the GSSE prevented the oxidative stress and copper depletion.

"In our research, obesity-induced leaky kidney and proteinuria are shown to be prevented by GSSE, which suggests the use of GSSE as a preventive nutriceutical for high-risk patients," said co-author Kamel Charradi, a researcher with the Laboratory of Bioactive Substance at the Center of Biotechnology of Borj-Cedria (CBBC) in Tunisia. This research group has previously published work showing the benefits of GSSE in combating obesity, heart dysfunction, brain lipotoxicity and kidney cancer.....

Ref : http://www.nrcresearchpress.com/doi/story/10.4141/news.2013.02.27.116#.UTM-5KJTCYk