9 Benefits of Coenzyme Q10 (CoQ10)

Coenzyme Q10, also known as CoQ10, is a compound that helps generate energy in your cells.

Your body produces CoQ10 naturally, but its production tends to decrease with age. Fortunately, you can also get CoQ10 through supplements or foods.

Health conditions like heart disease, brain disorders, diabetes, and cancer have been linked to low levels of CoQ10

It is not clear whether low levels of CoQ10 cause these diseases or are a result of them.

One thing is for certain: plenty of research has revealed CoQ10’s wide range of health benefits.

Here is all you need to know about CoQ10.

What Is CoQ10?

CoQ10 is a compound made by your body and stored in the mitochondria of your cells

The mitochondria are in charge of producing energy. They also protect cells from oxidative damage and disease-causing bacteria or viruses

CoQ10 production decreases as you age. Thus, older people seem to be deficient in this compound.

Some other causes of CoQ10 deficiency include

• Nutritional deficiencies, such as vitamin B6 deficiency
• Genetic defects in CoQ10 synthesis or utilization
• Increased demands by tissues as a consequence of disease
• Mitochondrial diseases
• Oxidative stress due to aging
• Side effects of statin treatments

Research has shown that CoQ10 plays several key roles in your body.

One of its primary functions is to help generate energy in your cells. It’s involved in making adenosine triphosphate (ATP), which is involved in energy transfer within cells

Its other crucial role is to serve as an antioxidant and protect cells from oxidative damage

Excessive amounts of free radicals lead to oxidative damage, which can interfere with regular cell functioning. This is known to cause many health conditions

Given that ATP is used to carry out all the body’s functions and oxidative damage is destructive to cells, it is not surprising that some chronic diseases have been linked to low levels of CoQ10

CoQ10 is present in every cell of your body. However, the highest concentrations are found in organs with the greatest energy demands, such as the heart, kidneys, lungs and liver

The following is a list of the 9 main benefits of CoQ10.

1. It May Help Treat Heart Failure

Heart failure is often a consequence of other heart conditions, such as coronary artery disease or high blood pressure

These conditions can lead to increased oxidative damage and inflammation of the veins and arteries

Heart failure occurs when these problems affect the heart to the point that it is unable to regularly contract, relax or pump blood through the body

To make matters worse, some treatments for heart failure have undesirable side effects, such as low blood pressure, while others could even further reduce CoQ10 levels

In a study of 420 people with heart failure, treatment with CoQ10 for two years improved their symptoms and reduced their risk of dying from heart problems

Also, another study treated 641 people with CoQ10 or a placebo for a year. At the end of the study, those in the CoQ10 group had been hospitalized less frequently for worsening heart failure and had fewer serious complications

It seems that treatment with CoQ10 could assist with restoring optimal levels of energy production, reduce oxidative damage and improve heart function, all of which can aid the treatment of heart failure

SUMMARY:CoQ10 seems to help treat heart failure by improving heart function, increasing ATP production and limiting oxidative damage.

2. It Could Help With Fertility

Female fertility decreases with age due to a decline in the number and quality of available eggs.

CoQ10 is directly involved in this process. As you age, CoQ10 production slows, making the body less effective at protecting the eggs from oxidative damage

Supplementing with CoQ10 seems to help and may even reverse this age-related decline in egg quality and quantity.

Similarly, male sperm is susceptible to the effects of oxidative damage, which may result in reduced sperm count, poor sperm quality and infertility

Several studies have concluded that supplementing with CoQ10 may improve sperm quality, activity and concentration by increasing antioxidant protection

SUMMARY:The antioxidant properties of CoQ10 could help improve sperm quality and reduce the decline in the number and quality of eggs in women.

3. It Might Help Keep Your Skin Young

Your skin is the largest organ in your body, and it’s widely exposed to damaging agents that contribute to aging.

These agents can be internal or external. Some internal damaging factors include cellular damage and hormonal imbalances. External factors include environmental agents, such as UV rays

Harmful elements can lead to reduced skin moisture and protection from environmental aggressors, as well as the thinning of the layers of the skin

Applying CoQ10 directly to the skin can reduce the damage from internal and external agents by increasing energy production in skin cells and promoting antioxidant protection

In fact, CoQ10 applied directly to the skin has been shown to reduce oxidative damage caused by UV rays and even decrease the depth of wrinkles

Lastly, people with low levels of CoQ10 seems to be more likely to develop skin cancer

SUMMARY:When applied directly to the skin, CoQ10 can reduce sun damage and increase antioxidant protection. Supplementing with CoQ10 may also help decrease the risk of skin cancer.

4. It Could Reduce Headaches

Abnormal mitochondrial function can lead to an increased calcium uptake by the cells, the excessive production of free radicals and decreased antioxidant protection. This can result in low energy in the brain cells and even migraines

Since CoQ10 lives mainly in the mitochondria of the cells, it has been shown to improve mitochondrial function and help decrease the inflammation that may occur during migraines

In fact, a study showed that supplementing with CoQ10 was three times more likely than a placebo to reduce the number of migraines in 42 people

Additionally, CoQ10 deficiency has beeobserved in people suffering from migraines.

One larger study showed that 1,550 people with low CoQ10 levels experienced fewer and less severe headaches after treatment with CoQ10

What’s more, it seems that CoQ10 not only helps treat migraines but may also prevent them

SUMMARY:Supplementing with CoQ10 seems to help prevent and treat migraines, as it increases mitochondrial function and reduces inflammation.

5. It Could Help With Exercise Performance

Oxidative stress can affect muscle function, and thus, exercise performance

Similarly, abnormal mitochondrial function can reduce muscle energy, making it hard for muscles to contract efficiently and sustain exercise

CoQ10 can help exercise performance by decreasing oxidative stress in the cells and improving mitochondrial functions

In fact, one study investigated the effects of CoQ10 on physical activity. Those supplementing with 1,200 mg of CoQ10 per day for 60 days showed decreased oxidative stress

Moreover, supplementing with CoQ10 can help increase power during exercise and reduce fatigue, both of which can improve exercise performance

SUMMARY:Exercise performance can be affected by oxidative stress and mitochondrial dysfunction. CoQ10 can help lower oxidative damage, promote exercise capacity and decrease fatigue.

6. It Could Help With Diabetes

Oxidative stress can induce cell damage. This can result in metabolic diseases like diabetes

Abnormal mitochondrial function has also been linked to insulin resistance

CoQ10 has been shown to improve insulin sensitivity and regulate blood sugar levels

Supplementing with CoQ10 might also help increase CoQ10 concentrations in the blood by up to three times in people with diabetes who typically show low levels of this compound

Also, one study had people with type 2 diabetes supplement with CoQ10 for 12 weeks. Doing so significantly reduced fasting blood sugar levels and hemoglobin A1C, which is the average of blood sugar levels over the past two to three months

Lastly, CoQ10 might help prevent diabetes by stimulating the breakdown of fats and reducing the accumulation of fat cells that could lead to obesity or type 2 diabetes

SUMMARY:Supplementing with CoQ10 can help increase insulin sensitivity and improve blood sugar levels.

7. It Might Play a Role in Cancer Prevention

Oxidative stress is known to cause cell damage and affect their function

If your body is unable to effectively fight oxidative damage, the structure of your cells can become damaged, possibly increasing the risk of cancer

CoQ10 may protect cells from oxidative stress and promote cellular energy production, promoting their health and survival

Interestingly, cancer patients have been shown to have lower levels of CoQ10.

Low levels of CoQ10 have been associated with up to a 53.3% higher risk of cancer and indicate a poor prognosis for various types of cancer

What’s more, one study also suggested that supplementing with CoQ10 may help reduce the chance of cancer recurrence

SUMMARY:CoQ10 plays a critical role in the protection of cell DNA and cell survival, both of which are strongly linked to cancer prevention and recurrence.

8. It Is Good for the Brain

Mitochondria are the main energy generators of brain cells.

Mitochondrial function tends to decrease with age. Total mitochondrial dysfunction can lead to the death of brain cells and diseases like Alzheimer’s and Parkinson’s

Unfortunately, the brain is very susceptible to oxidative damage due to its high fatty acid content and its high demand for oxygen.

This oxidative damage enhances the production of harmful compounds that could affect memory, cognition and physical functions

CoQ10 may reduce these harmful compounds, possibly slowing the progression of Alzheimer’s and Parkinson’s disease

SUMMARY:CoQ10 has been shown to protect brain cells from oxidative damage and reduce the action of harmful compounds that can lead to brain disease.

9. CoQ10 Could Protect the Lungs

Of all your organs, your lungs have the most contact with oxygen. This makes them very susceptible to oxidative damage.

Increased oxidative damage in the lungs and poor antioxidant protection, including low levels of CoQ10, can result in lung diseases like asthma and chronic obstructive pulmonary disease (COPD)

Furthermore, it has been shown that people suffering from these conditions present lower levels of CoQ10

A study demonstrated that supplementing with CoQ10 reduced inflammation in individuals who had asthma, as well as their need for steroid medications to treat it

Another study showed improvements in exercise performance in those suffering from COPD. This was observed through better tissue oxygenation and heart rate after supplementing with CoQ10

SUMMARY:CoQ10 can reduce oxidative damage and inflammation that results in diseases of the lungs.

Dosage and Side Effects

CoQ10 comes in two different forms — ubiquinol and ubiquinone.

Ubiquinol accounts for 90% of the CoQ10 in the blood and is the most absorbable form. Thus, it’s recommended to choose from supplements containing the ubiquinol form

The standard dose of CoQ10 ranges from 90 mg to 200 mg per day. Doses up to 500 mg seem well tolerated, and several studies have used even higher doses without any serious side effects

Because CoQ10 is a fat-soluble compound, its absorption is slow and limited. However, taking CoQ10 supplements with food can help your body absorb it up to three times faster than taking it without food

Additionally, some products offer a solubilized form of CoQ10, or a combination of CoQ10 and oils, to improve its absorption

Your body does not store CoQ10. Therefore, its continued use is recommended to see its benefits

Supplementing with CoQ10 appears to be well tolerated by humans and have low toxicity

In fact, participants in some studies showed no major side effects taking daily doses of 1,200 mg for 16 months

However, if side effects appear, it is recommended to divide the daily dose into two to three smaller doses.

SUMMARY:Since CoQ10 is fat-soluble, it is recommended to take it with food or use products that combine it with oils to improve its absorption. Supplementing with CoQ10 appears to be well tolerated by individuals and has low toxicity.

Food Sources of CoQ10

While you can easily consume CoQ10 as a supplement, it can also be found in some foods.

It appears that CoQ10 is similarly absorbed in capsule form or through foods

The following foods contain CoQ10:

• Organ meats: Heart, liver and kidney
• Some muscle meats: Pork, beef and chicken
• Fatty fish: Trout, herring, mackerel and sardine
• Vegetables: Spinach, cauliflower and broccoli
• Fruit: Oranges and strawberries
• Legumes: Soybeans, lentils and peanuts
• Nuts and seeds: Sesame seeds and pistachios
• Oils: Soybean and canola oil

SUMMARY:CoQ10 is found in some foods, especially organ meats. Also, it seems that it’s as equally well absorbed through foods as it is through supplements.

The Bottom Line

CoQ10 is a fat-soluble, vitamin-like compound that seems to have many health benefits.

It is involved in the production of cellular energy and serves as an antioxidant.

These properties make it helpful in the preservation of cells and the prevention and treatment of some chronic diseases.

CoQ10 has been shown to help improve heart health and blood sugar regulation, assist in the prevention and treatment of cancer and reduce the frequency of migraines.

It could also reduce the oxidative damage that leads to muscle fatigue, skin damage and brain and lung diseases.

CoQ10 can be found as a supplement that seems to be well tolerated. Additionally, it’s found in some foods like animal organs, vegetables and legumes.

Since CoQ10 production decreases with age, adults of every age could benefit from more of it.

Whether you consume more foods with a high CoQ10 content or take supplements, CoQ10 could benefit your health.

Read – How Do You Treat A Snake Bites

Suspected Snake bites?

Injury resulting from snake biting a human.

Physical Finding and Clinical Presentation
In addition to local tissue injury, envenomation may affect the renal, neurologic, gastrointestinal, vascular, and coagulation systems. Symptoms vary widely depending on type of envenomation. Not all snakebites are poisonous, and not all bites lead to envenomation. Species-specific signs and symptoms following envenomation are discussed.
CROTALIDAE (PIT VIPERS)

Local Signs and Symptoms

Pain within 5 min
Edema within 30 min
Erythema of site and adjacent tissues/serous or hemorrhagic bullae, ecchymosis, and/or lymphangitis over the ensuing hours
If no edema or erythema is manifested within 8 hr after a confirmed crotalid snakebite, it is safe to assume envenomation did not occur. (Roughly 25% of cases do not involve envenomation.) In general, rattlesnake bites are more severe than those of the other snakes in the Crotalidae family.

Systemic manifestations may include:

Mild to moderate nausea/vomiting, perioral paresthesias, metallic taste, tingling of fingers or toes (especially with rattlesnake bites), and/or fasciculations (local or generalized)
Severe hypotension (due to increased vascular permeability), mental status change, respiratory distress, tachycardia, acute renal failure, rhabdomyolysis, and coagulopathies including intravascular hemolysis and disseminated intravascular coagulation.
ELAPIDAE (CORAL SNAKES):

Local symptoms are far less pronounced (little or no pain/swelling immediately after the bite).
Neurologic symptoms are more common due to neurotoxins in elapid venom.
Systemic symptoms predominate, but onset may be delayed for up to 12 hr. Examples include:
1. Altered mental status and cranial nerve palsies featuring ptosis, dysphagia, or dysarthria
2. Tremors
3. Intense salivation, nausea, vomiting, or abdominal pain
4. Loss of DTRs and respiratory depression (late manifestations)
Differential Diagnosis
Harmless snakebite
Scorpion bite
“Dry bite”
Insect bite
Cellulitis
Laceration or puncture wound
Necrotizing fasciitis

Workup
An estimated 25% of venomous snakebites do not result in envenomation, but all cases of suspected envenomation should be observed for 8 hr or longer
Check for signs of envenomation.
1. Swelling, tenderness, redness, ecchymosis, or blebs at the bite site
2. Elevated protime, decreased fibrinogen or platelets
3. Systemic signs such as hypotension, bleeding complications, vomiting, diarrhea, angioedema, or neurotoxicity
Determine if patient has indications for antivenom. Continual reassessment is indicated throughout the observation period because severity of symptoms may change.
Laboratory Tests
For all suspected envenomations, obtain CBC (with peripheral smear and platelet count), DIC screen (PT/INR, PTT, fibrinogen, fibrin degradation products, d-dimer), ECG, serum electrolytes, BUN, Cr, and urinalysis. Serial measurements of hemoglobin, platelets, protime, and fibrinogen are needed to monitor for acute and delayed hematologic complications.
For more severe bites, consider LFTs, sedimentation rate, creatine kinase (rule out rhabdomyolysis), ABG, and type and crossmatch.
Other: consider chest radiograph in cases with severe envenomation or in patients over 40 years old with underlying cardiopulmonary disease; radiograph of bite site for retained fangs (poor sensitivity); head CT if concern is raised for intracranial hemorrhage
Treatment
IN THE FIELD: For a suspected snakebite:

Transport immediately to nearest medical facility. No treatments in the field should delay travel to the nearest facility where an antivenom agent can be given if necessary.
Immobilize affected part.
Remove any constricting items. Applying tourniquets, incising, and applying suction to the wound is discouraged. Tourniquets cause more local tissue damage due to tissue necrosing venom seen in crotalid bites and should not delay transport to a medical facility.
Do not apply ice; keep victim warm.
Avoid alcohol, stimulants (caffeine), or agents that can suppress mental status.
IN THE HOSPITAL

Record vital signs: BP, HR, T, RR, and O2 sat.
Establish intravenous access and initiate IV hydration with crystalloid if the patient is hypotensive.
Obtain time of bite and description of snake if possible. Crotalids have a triangle-shaped head, nostril holes (pits), and elliptical pupils. The most dangerous of the crotalids is the rattlesnake, distinguished by its telltale rattle. Elapids, like the western and eastern coral snakes of the U.S., have brightly colored red, black, and yellow stripes.
Obtain and initiate reconstitution of appropriate antivenom. (Antivenoms are typically supplied in powder form and must be reconstituted before administration. If using older antivenoms, this process can take up to 1 hr, so it is recommended that it be initiated as soon as the patient arrives in the ED.)
1. Inspect site of bite for fang marks and local symptoms.
2. Delineate margins of erythema/edema with a marker.
3. Measure circumference of bitten part at two or more proximal sites and compare with unaffected limb; repeat every 15 to 20 min; assess for extension of erythema/edema.
4. Conduct a complete neurologic examination.
5. Obtain past medical history; ask about allergies to horse serum in those previously treated for snakebite.
If no signs of envenomation:
1. Clean and immobilize affected part.
2. Immunize against tetanus.
3. For crotalid bites, observe patient for at least 8 hr. If, at the end of this interval, local and systemic sequelae are absent and lab values remain normal, the likelihood of significant envenomation is low, and the patient can be discharged from the acute setting. Some sources recommend observing patients with crotalid bites to the lower extremities for at least 24 hours because swelling in the larger compartments of the legs could be slower and less easily recognizable. All definitive elapid bites should be treated. If elapid bite is only suspected, the patient must be monitored for up to 18 hr as symptoms can be delayed.
Patients who have progressive local symptoms or any systemic symptoms should be considered for antivenom. Crotalid envenomations without any progressive local or any systemic symptoms can be monitored for 12 to 24 hours, with repeat labs obtained 4 to 6 hours before discharge. If they have no new symptoms during that period of observation, they may be safely discharged. Specifically, copperhead bites often need no further interventions.
TREATMENT OF NONNATIVE (EXOTIC) SNAKEBITES

For bites by exotic or nonnative snakes, contact a Poison Control Center or your local zoo. (Zoos with exotic snakes are required to maintain a supply of snake-specific antivenom on their premises.)
Complications
Allergic reactions were very frequent with horse serum antivenoms. CroFab from sheep serum should be preferentially used over equine serum if available.
Anaphylaxis occurs within 30 min and should be treated by immediately stopping the infusion to managing the symptoms of anaphylaxis, including epinephrine SQ or IM initially and IV if needed, diphenhydramine IV, and hydrocortisone IV. If the anaphylactic symptoms can be managed and the envenomation is severe, the infusion can then be resumed.
Delayed hematologic complications are common and can manifest up to 4 days post treatment. Most bleeding is self-limited but can rarely be severe, necessitating close follow-up.
Serum sickness occurs 7 to 14 days after antivenom administration and is characterized by fever, rash, arthralgias, and lymphadenopathy. It can be treated with prednisone 60 mg/d PO, tapered over 7 to 10 days.
Injuries also result from:
1. Tourniquet placement on the field, which should be avoided
2. Ice application (cryotherapy), which can worsen tissue damage

Dental Implant Surgery

Is It Flu, Or Flu-Like? The Difference Matters

General

We’re in the middle of flu season, so if you get sick and head to the doctor for help, you might assume you have the flu. But what if your doctor instead diagnoses you with “flu-like illness?”

What is the difference between  the flu and flu-like illness?

The flu is “a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and sometimes the lungs,” the CDC says. It says symptoms include some or all of the following:

• Fever
• Cough and sore throat
• Runny or stuffy nose
• Muscle or body aches and chills
• Headaches
• Fatigue

“Influenza-like illness,” also called “flu-like illness,” is a more wide-ranging category. The CDC says that with flu-like illness, you have a fever of at least 100 F and a cough or sore throat, but the cause of the symptoms isn’t known.

How can doctors tell if you have flu or flu-like illness?

The flu is diagnosed from a swab test of your nose or throat. Flu-like illness is a clinical diagnosis, meaning it doesn’t involve an official test. A doctor simply decides by examining you.

Flu-like illness can be the diagnosis when doctors aren’t sure what virus is at play since signs and symptoms of bad colds and several other respiratory viruses can be difficult to distinguish from the flu.

“Flu-like illness can include other respiratory viruses that could make people feel that way — common cold viruses, RSV, parainfluenza, even rhinovirus — the most common cause of the common cold,” says Angela Campbell, MD, a medical officer in the CDC’s Flu Division in Atlanta. “All can cause symptoms similar to the flu.”

Michael Ison, MD, a professor of infectious diseases and organ transplantation at Northwestern University in Evanston, IL, says regardless of the cause, treatment is similar.

“What influenza-like illness is saying to us is that you have a virus likely affecting your respiratory system that is making you feel crummy and, currently aside from influenza, there aren’t good therapies for these other viruses, so we just treat the symptoms,” he says.

An flu-like illness diagnosis can also mean your doctor thinks you have the flu but doesn’t see the point in doing an official flu test.

“Flu testing may be helpful for some, but for the majority of people, you don’t need to expect to receive a test,” Campbell says. “Most people probably won’t require testing because it won’t change what your doctor recommends in terms of symptomatic care.”

William Schaffner, MD, an infectious disease specialist at Vanderbilt University School of Medicine in Nashville, says tests can also be expensive and unreliable, and many doctors only use them when they aren’t sure of a diagnosis, which is rarely the case during a flu outbreak.

“For the most part, the official flu tests are done if you are hospitalized with an influenza-like illness. Some doctors will have the rapid test available in their offices, but the rapid test can be very inaccurate,” he says. “So a lot of people say if you are in the middle of an influenza outbreak and a patient comes into the office with an illness that looks like influenza, just go ahead and treat them. Don’t bother with the test.”

How do you treat flu vs. flu-like illness?

The CDC says antiviral drugs are a treatment option for the flu. They can lessen symptoms and shorten the time you are sick by a day or two. The agency says they are most effective when taken within 48 hours of the start of symptoms, although they can still help fight severe flu complications when given after that.

Whether you have the flu or flu-like illness, doctors also recommend that you:

• Drink lots of fluids. Fever and viral infections can be dehydrating, particularly for younger and older people. “It not only makes you uncomfortable, it can also predispose you to the development of pneumonia,” Schaffner says.
• Rest and get plenty of sleep. Your body needs downtime to recover.
• Take over-the-counter cold and flu medicines to treat a variety of symptoms, such as congestion and cough. Tylenol, Advil, or Motrin can help control fever, aches, and pains.
• Use steam from a hot shower to moisten mucous membranes, open up your sinuses, and promote drainage if you are congested.

Doctors say it’s important to know that antibiotics won’t help with the flu since they only treat bacterial infections. Antivirals can be an option to treat both flu and flu-like illness, doctors say.

“A lot of patients want to go home with antibiotics, but a flu-like illness means it is more than likely being caused by a virus, so you don’t need an antibiotic,” says Ison, the Northwestern professor. “Getting an antibiotic you don’t need can cause antibiotic resistance to develop, and then if you get pneumonia, for example, we may not have good drugs or any drugs to treat the infection.”

What should you do if you think you have the flu or a flu-like illness?

For otherwise healthy patients, the CDC says you can expect to be sick with the flu for several days to 2 weeks. flu-like illness is similar.

“If a patient feels having an extra day or two of being back to work is beneficial, then seek the care of a physician and inquire about an antiviral,” Ison says. “If symptoms are mild and you want to tough it out at home, that is reasonable too.”

But if you have underlying medical conditions, are pregnant, or have other high-risk conditions, you may be likely to get more serious infections, hospitalization, or even death from flu complications, so experts say don’t try to manage the illness alone.

“If you are at high risk … go see your doctor early. If you are a person with an underlying medical condition, a child less than 2, or a person over 65, don’t wait. Go see a doctor early and let them decide if you should be treated with antivirals,” says Campbell, the CDC medical officer.

When am I likely to get sick with the flu or flu-like illness?

The CDC tracks levels of both the flu and flu-like illness during flu season, which can begin as early as October or November and continue as late as May, but generally peaks between December and February.

“We track influenza-like illness across the country, and we know when lab-confirmed flu goes up, (flu-like illness increases. They go together,” Campbell explains.

What complications should I look out for?

Your fever will go away first, but don’t worry if your cough sticks around for a while. “The coughing can last longer because these viruses can set up an inflammatory response, and it takes longer for bronchial tubes and sinuses to calm down,” says Schaffner, the Vanderbilt University specialist.

You should notice a general trend of improvement after a few days. If you don’t, and your fever persists for a couple of days or you have a cough that worsens, call your doctor.

Other signs of complications include symptoms that improve and then get worse, more shortness of breath, or a fever that goes away and then comes back. These can be signs of secondary infections, and you should call a doctor right away.

How can I best practice prevention?

Doctors say the best thing you can do to keep from getting sick is get the flu vaccine at the start of flu season. It may protect you from getting the flu, or it can make your symptoms less severe. The CDC says the flu vaccination also reduces deaths, admissions to the intensive care unit (ICU), how long people stay in the ICU, and the amount of time people spend in a hospital from the flu.

If you have a condition like diabetes, lung disease, heart disease, or some other condition that suppresses your immune system, or if you are older, you may also want to avoid crowds if a flu epidemic is sweeping your area.

“If you have an underlying illness and get the flu, you are more likely to get complications of flu, like pneumonia, and have to go to the hospital,” Schaffner says. “So it might be time to be a bit reclusive if there is a flu outbreak where you live.”

If you do get sick, do what you can to keep it from spreading to others. Recommendations include:

• Keep it to yourself. “Respiratory infections are very contagious, starting from a day before you get sick to well into your recovery,” Schaffner says. Avoid close contact with people, stay in bed, or separate yourself from your family, roommates, or loved ones so you don’t give it to everyone else.
• Stay home. Don’t go to work, school, the gym, religious services, or run errands while your symptoms are severe, because you don’t want to spread the germs around.
• Cover your mouth and nose with a tissue when coughing or sneezing to keep from spreading the virus.
• Clean your hands. This helps keep germs from spreading.
• Avoid touching your nose, eyes, and mouth, since germs often spread when you do this after touching something contaminated.
• Clean and disinfect common surfaces at home, work, and school, especially when someone is sick, to keep germs from spreading.

NEW STUDY DESCRIBES HOW ALZHEIMER’S DISEASE SPREADS THROUGHOUT THE BRAIN

General

Alzheimer’s disease is a devastating brain illness that affects an estimated 47m people worldwide. It is the most common cause of dementia in the Western world. Despite this, there are currently no treatments that are effective in curing Alzheimer’s disease or preventing its relentless progression.

Alzheimer’s disease is caused by the build-up of two abnormal proteins, beta-amyloid and tau. Tau is particularly important because it causes neurons and their connections to die, preventing brain regions from communicating with each other normally. In the majority of cases, tau pathology first appears in the memory centres of the brain, known as the entorhinal cortex and hippocampal formation. This has been shown to occur many years before patients have any symptoms of disease.

Over time, tau begins to appear in increasing quantities throughout the brain. This causes the characteristic progression of symptoms in Alzheimer’s diseases, where initial memory loss is followed by more widespread changes in thinking and behaviour that lead to a loss of independence. How this occurs has been controversial.

TRANSNEURONAL SPREAD

In our study, published in the journal Brain, we provide the first evidence from humans that tau spreads between connected neurons. This is an important step, because stopping this spread at an early stage might prevent or freeze the symptoms of Alzheimer’s disease.

This idea, called “transneuronal spread”, has been proposed before and is supported by studies in mice. If abnormal tau is injected into a healthy mouse brain, it quickly spreads and causes the mice to manifest dementia symptoms. However, it had not previously been shown that this same process occurs in humans. The evidence from mouse studies was controversial, as the amount of tau injected was relatively high, and disease progression occurred much more rapidly than it does in humans.

In our study, we combined two advanced brain imaging techniques. The first, positron emission tomography (PET), allows us to scan the brain for the presence of specific molecules. With this, we were able to directly observe the abnormal tau in living patients, to see exactly how much of it was present in each part of the brain.

The second, functional magnetic resonance imaging (fMRI), measures blood flow in the brain in real time. This allowed us to observe the activity produced by brain regions communicating with each other. For the first time, by scanning the same people with both methods, we were able to directly relate the connections of the brain to the distribution of abnormal tau in living humans with Alzheimer’s disease.

We used a mathematical technique called “graph analysis” to analyse brain connectivity. This technique involved splitting the brain up into 598 regions of equal size. We then treated the connectivity between regions like a social network, assessing factors such as the number of contacts a brain region had, how many “friendship” groups it took part in, and how many of a brain region’s contacts were also contacts of each other.

In a flu epidemic, people with a large number of social contacts are most likely to become infected and then to pass the infection on to others. Similarly, the transneuronal spread hypothesis predicts that strongly connected brain regions will accrue most tau. This is what we observed. This relationship was present within each brain network individually, as well as across the whole brain.

We were also able to exclude potential alternative explanations for the appearance of tau throughout the brain. It had previously been suggested that tau might appear at brain regions that were vulnerable because of high metabolic demand or a lack of support from their neighbours. While it is possible that these factors are important in neuronal death, our observations were not consistent with them being the primary drivers of the initial accumulation of abnormal tau.

In addition, by looking at patients with a range of disease severity, from mild cognitive impairment through to established Alzheimer’s disease, we were able to disentangle the causes of tau accumulation from its consequences. We showed that increasing amounts of tau in Alzheimer’s disease caused the brain to become less connected overall, and the connections that remained became increasingly random.

LONG-RANGE CONNECTIONS

Finally, we contrasted the findings in Alzheimer’s disease to a rarer condition called progressive supranuclear palsy (PSP), which affects approximately three in every 100,000 people. This condition is also caused by tau, but it remains confined to the base of the brain. We demonstrated that in PSP the evidence did not support transneuronal spread. This might be because of the different structure of abnormal tau pathology in the two diseases. In Alzheimer’s disease, tau is present in “paired helical filaments”, while in PSP it is in “straight filaments”.

We showed that as PSP progresses, direct long-range connections are preferentially damaged, meaning that information had to take a more indirect route across the brain. This might explain why, when asked a question, patients with PSP usually respond slowly but correctly.

Overall, evidence of transneuronal spread in humans with Alzheimer’s disease provides proof of concept for exciting new treatment strategies to lock up tau pathology before it can cause significant damage.