Acne antibiotic may be treatment for brain fever

Minocycline reduces death in JE-infected mice and could do the same in humans, say researchers.If Indian scientists can transfer their laboratory success to human trials, a common acne-treating antibiotic could well turn out to be a life saver for patients of Japanese encephalitis (JE), commonly known as brain fever.

Researchers at the National Brain Research Centre (NBRC) in Manesar, Haryana, have shown that the common antibiotic minocycline reduces death in JE-infected mice and believe it could do the same in humans.

“Even if we replicate a fraction of the success in animals reported by NBRC team, we can save several lives and prevent many others from being maimed every year,” says N.C. Borah, managing director of the Guwahati Neurological Research Centre (GNRC).

He plans to undertake clinical trials in May at GNRC and two other hospitals in Guwahati and Dibrugarh as each of these centres receive 300-400 seriously ill JE patients every season that typically begins with the monsoon.

A viral disease that causes inflammation of the brain, JE kills about one-third of its patients and half the remaining end up with serious disabilities including cognitive and behavioural impairment. The infection is endemic in India, where 135 districts in 15 states routinely report cases, according to the Union ministry of health and family welfare.

“No effective treatment exists today, what we have is only supportive,” says Anirban Basu, the lead researcher from NBRC, who thinks clinical success could lead to immediate therapy, as minocycline is an inexpensive and freely available drug currently used for treating bacterial infections of the skin, teeth and urinary tract.

Basu’s early work showed that minocycline not only reduced the inflammation in the brain, but also stemmed loss of healthy neuronal cells and decreased the viral load (a measure of the severity of a viral infection). However, questions like how effective the drug will be, if there’s a time lag between the infection and the treatment, or whether it will reduce the disabilities in survivors can be answered only after the human trials, says Basu.

Scientists believe it’s a fairly safe bet, as it’s the efficacy rather than the safety that needs to be ascertained, because the drug is already in use. “It’s a straightforward case, but we are hitting a stone wall,” says NBRC director Vijayalakshmi Ravindranath, since there’s no government agency to do translational research or even coordinate it. Translational research helps convert laboratory findings into therapeutics—or from bench to bedside. “In the absence of intellectual property, there’s no money to be made here or else we could have gone to a commercial agency for trials.”

The cost of the trial is not a trivial issue either. But the department of biotechnology, of which NBRC is an autonomous institute, has promised to extend support. Trials in children are difficult and expensive, as each centre needs to have sufficient number of ventilators, which can cost up to Rs 20,000 per day for every child. “I am pushing it; we hope to get started by this season,” says Ravindranath. NBRC has identified a contract research organization and is chalking out the trial design, things which research institutions in the country typically don’t do.

Borah thinks the sample of 250 patients can be recruited in just one season in the north-east, which has the highest incidence of JE. “We will run the study for four weeks and it can be completed by November,” he adds.

The successful and timely completion of this trial is important for more than one reason. Minocycline has shown promising results in other neurogenerative disorders including Alzheimer’s and Parkinson’s disease and multiple sclerosis, a nervous system disorder. Moreover, its success in JE could be an encouragement for further initiatives in “repurposing” of existing or discarded drugs. “This is a good strategy for developing countries,” says Basu.

Source:TOI

New Antibiotic Found in Fish Cells

Scientists have found that certain cells in a hybrid striped bass commonly available in the United States contain a new family of antibiotics. Edward Noga and Umaporn Silphaduang, both of North Carolina State University in Raleigh, have named the antibiotics "piscidins" for the Latin word for fish, pisces.

The piscidins are actually tiny protein antibiotics produced by mast cells, which are found in the immune systems of all vertebrates.

Many organisms produce their own antibiotics to protect themselves against disease-causing microbes. More than a decade ago, for example, researchers discovered that frogs oozed a new class of natural antibiotics in their skins, which were later named "magainins." Crocodiles produce unique antibiotics that circulate in their blood stream.

For years there has been considerable interest in discovering new antibiotics that can kill a variety of human pathogens. A growing number of bacteria are becoming resistant to existing antibiotics, and recent events such as the spread of anthrax and huge public demand for Cipro have given the search for new anti-microbial drugs greater urgency.

The mast cells in which the piscidins were found play a key role in allergic reactions. In people, mast cells release histamines and trigger reactions such as asthma and hay fever.

Although it's known that mast cells summon the immune system to respond when the body is threatened by invading bacteria, the discovery of antibiotics inside the fish mast cells is the first evidence that these cells may be able to kill bacteria directly, said Noga.

He is particularly excited about piscidins because he thinks it may be more difficult for bacteria to develop a resistance to this new class of antibiotics.

Many antibiotic drugs are designed to recognize a specific molecule on the outer surface of a bacterium, which then targets the microbe for destruction. But bacteria evolve very rapidly, and a single mutation that alters the look of the target molecule can help the bacterium evade annihilation.

The piscidins, however, mount a more general attack against some very common features of bacteria, says Noga, who is co-author of a report on the findings published in the journal Nature. "Piscidins make a hole in the membrane, which cause the bacteria to pop open and die within minutes," said Noga.

This general form of attack means that single mutations are unlikely to help bacteria evolve resistance. But despite the promising results, Noga remains cautious. "When it comes to nature, never say never," he said.

The finding may have significant implications not only for human medicine but also for veterinary medicine and the U.S. aquaculture industry

Source: Nationalgeographic

Antibiotics won’t cure viral fever

The next time you are down with viral fever, don’t rely on antibiotics to get better. You might have come back with a prescription for antibiotics after the doctor diagnosed you with a viral infection but rest assured they will not cure you.

Antibiotics are made specifically for the treatment of bacterial infections. Not only does taking antibiotics for a viral infection fail to cure it, the drug also ends up killing the harmless and protective bacteria in the body.

Says Dr C M Gulathi, editor, Monthly Index of Medical Specialities: ‘‘Prescribing antibiotics for viral is wrong as it serves no purpose. In fact, it can lead to harmful side effects. Most kinds of fever and throat infections are results of viral infection.’’

Most doctors are under immense pressure from the patient to prescribe drugs as medicines usually give a sense of security to the patient, making them feel better instantly. Explaining why doctors prescribe antibiotics for viral infections, Gulathi adds: ‘‘Doctors know that patients are going to start distrusting them if they don’t prescribe medicines. Secondly, doctors don’t spend too much time making the diagnosis these days. Prescribing antibiotics for viral infection is an outcome of poor diagnosis. Thirdly, doctors are also under pressure from private pharmaceutical companies to boost their business by prescribing their drugs.’’

   A virus is a small infectious agent that attaches itself to a living cell known as the host cell and starts reproducing. This leads to what we know as a viral infection. The virus attaches itself to the host cell and releases its DNA in the cell, forcing it to reproduce. The cell eventually dies as the virus prevents it from performing its normal functions. When it dies the cell releases new viruses that infect other cells. The most common viral infections are those of the nose, throat and the upper airways — in other words, upper respiratory infections. Sore throat, sinusitis, common cold and influenza are all caused by viruses.

   Viral infections are usually diagnosed through the symptoms presented. Accurate diagnosis can become difficult sometimes, in which case blood tests and cultures might be needed. Drugs that combat viral infections are known as antiviral drugs. Most antiviral drugs interfere with replication of the virus. These drugs include interferons, immunoglobulins and vaccines. Interferons stop viral infections. Immunoglobulin have antibodies which fight infection.

   There are ten times as many bacteria as human cells in our body. Most of these bacteria are harmless or protective to the immune system. Along with killing the pathogenic bacteria, which can cause infections, antibiotics can kill the bacteria needed by the body as well. It can also make the harmless bacteria immune to antibiotics.

   Antibiotics are not effective against viral infections but if a person has a bacterial infection in addition to a viral infection, an antibiotic is often necessary.

Source:TOI