VANCOUVER - A Vancouver police officer has been charged with assault for pushing a disabled woman to the ground in an incident caught on video.
Const. Taylor Robinson was charged after a three-month investigation of the incident by the New Westminster police department.
Robinson was among three officers on foot patrol in the city's Downtown Eastside last June.
The video shows the woman walking by the officers when one of them pushes her from the back.
The officer didn't help the woman, who was assisted by other people on the street as the three officers walked away.
Robinson, who's been with the Vancouver Police Department since March 2009, has been placed on administrative duty pending the outcome of his court case.
Wednesday, December 8, 2010
Monday, December 6, 2010
Sunday, November 28, 2010
Police who brutalize should be locked up
Lac La Biche RCMP officer pleads guilty to 'appalling' assault
EDMONTON — An RCMP officer who beat a man in custody at the Lac La Biche RCMP detachment last year has pleaded guilty to assault in provincial court where a video of the incident was shown.
The video shows Const. Desmond Sandboe lunging across a hallway toward Andrew Clyburn after the man appears to say something to the officer. Clyburn is smashed against a wall, taken to the ground and punched repeatedly in an assault that lasts approximately 40 seconds and leaves the floor smeared with fluid.
“The RCMP finds this incident appalling. The public trusts the RCMP to care for them in our custody, and we take that responsibility very seriously,” said Supt. Joe Loran, acting commanding officer for the RCMP’s K-Division, in a statement.
Court on Friday heard RCMP officers were called to the Almac bar in Lac La Biche around 3 a.m. on Sept. 13, 2009, to deal with Clyburn, who had been in a fight and was causing problems for staff.
When RCMP arrived, they found Clyburn intoxicated and bleeding from injuries. He was arrested for public intoxication.
Court heard officers took Clyburn to a local hospital. Nurses met the group at the RCMP cruiser but said they would not treat Clyburn because he was belligerent and was smashing his head inside the car. Nurses noted a cut to the back of his head, along with other injuries.
Clyburn was taken to the local RCMP detachment around 3:15 a.m. and put into a cell. Around 7:15 a.m. Clyburn was taken out of his cell and escorted into a hallway area. Sandboe had just started his shift.
The video shows Clyburn, who is not wearing shoes, getting ready to put on a sweatshirt when the assault occurs. Clyburn appears to say something to the officer, although there is no audio in the recording. That’s when the officer lunges at Clyburn from across the hallway, smashing him twice against the wall and punching him repeatedly as he takes Clyburn to the ground.
The officer continues to punch Clyburn, while the man raises his hands to protect his face. He punches Clyburn at least 10 times, while the pair struggle and move along the ground of the hallway.
The assault lasts approximately 40 seconds and two other officers can be seen watching the incident. The video then shows Clyburn being hauled to his feet and taken back down the hallway. The video shows the previously clean floor smeared with fluid.
The case is scheduled to be back in court Jan. 27, 2011, when the defence is expected to present more facts related to the case. A pre-sentence report has been ordered.
Sandboe, a nine-year veteran of the RCMP, has been suspended without pay, a disciplinary action reserved for the most serious of conduct matters.
“Const. Sandboe’s conduct has violated the public’s trust. He has also done a great disservice to the men and women of the RCMP who daily meet and exceed the public’s expectations and who uphold our values,” said Loran, the acting commanding officer.
Sandboe was initially charged with assault causing bodily harm when the charges were announced in 2009 by the Alberta Serious Incident Response Team, which investigates actions of police in cases that result in death or injury. The charge resulted from the ASIRT investigation.
The RCMP is also conducting a code of conduct investigation, which will be completed after the case goes through the court system and could result in Sandboe’s dismissal.
Lac La Biche is about 200 kilometres northeast of Edmonton.
EDMONTON — An RCMP officer who beat a man in custody at the Lac La Biche RCMP detachment last year has pleaded guilty to assault in provincial court where a video of the incident was shown.
The video shows Const. Desmond Sandboe lunging across a hallway toward Andrew Clyburn after the man appears to say something to the officer. Clyburn is smashed against a wall, taken to the ground and punched repeatedly in an assault that lasts approximately 40 seconds and leaves the floor smeared with fluid.
“The RCMP finds this incident appalling. The public trusts the RCMP to care for them in our custody, and we take that responsibility very seriously,” said Supt. Joe Loran, acting commanding officer for the RCMP’s K-Division, in a statement.
Court on Friday heard RCMP officers were called to the Almac bar in Lac La Biche around 3 a.m. on Sept. 13, 2009, to deal with Clyburn, who had been in a fight and was causing problems for staff.
When RCMP arrived, they found Clyburn intoxicated and bleeding from injuries. He was arrested for public intoxication.
Court heard officers took Clyburn to a local hospital. Nurses met the group at the RCMP cruiser but said they would not treat Clyburn because he was belligerent and was smashing his head inside the car. Nurses noted a cut to the back of his head, along with other injuries.
Clyburn was taken to the local RCMP detachment around 3:15 a.m. and put into a cell. Around 7:15 a.m. Clyburn was taken out of his cell and escorted into a hallway area. Sandboe had just started his shift.
The video shows Clyburn, who is not wearing shoes, getting ready to put on a sweatshirt when the assault occurs. Clyburn appears to say something to the officer, although there is no audio in the recording. That’s when the officer lunges at Clyburn from across the hallway, smashing him twice against the wall and punching him repeatedly as he takes Clyburn to the ground.
The officer continues to punch Clyburn, while the man raises his hands to protect his face. He punches Clyburn at least 10 times, while the pair struggle and move along the ground of the hallway.
The assault lasts approximately 40 seconds and two other officers can be seen watching the incident. The video then shows Clyburn being hauled to his feet and taken back down the hallway. The video shows the previously clean floor smeared with fluid.
The case is scheduled to be back in court Jan. 27, 2011, when the defence is expected to present more facts related to the case. A pre-sentence report has been ordered.
Sandboe, a nine-year veteran of the RCMP, has been suspended without pay, a disciplinary action reserved for the most serious of conduct matters.
“Const. Sandboe’s conduct has violated the public’s trust. He has also done a great disservice to the men and women of the RCMP who daily meet and exceed the public’s expectations and who uphold our values,” said Loran, the acting commanding officer.
Sandboe was initially charged with assault causing bodily harm when the charges were announced in 2009 by the Alberta Serious Incident Response Team, which investigates actions of police in cases that result in death or injury. The charge resulted from the ASIRT investigation.
The RCMP is also conducting a code of conduct investigation, which will be completed after the case goes through the court system and could result in Sandboe’s dismissal.
Lac La Biche is about 200 kilometres northeast of Edmonton.
Thursday, November 25, 2010
Sometimes cops are criminals.
Not wearing badges, not having to be interviewed, and the fact that victims have the burden of proof is enraging.
No police charged for civilian G20 injuries: SIU
6 men lodged complaints
Last Updated: Thursday, November 25, 2010 | 6:01 PM ET
CBC News
The SIU says it has been unable to identify police officers it says used excessive force when arresting two men at a G20 protest on June 26 at Queen's Park in Toronto. (Canadian Press)
An Ontario police watchdog is not holding any officers accountable for separate incidents in which it says excessive force was likely used against two civilians at a G20 protest in Toronto.
The province's Special Investigations Unit, which probes police operations where civilians are hurt or killed, on Thursday released the results of its investigation into six complaints of police brutality during last June's G20 summit.
The six men in question all complained that they were injured when law enforcement officers used excessive force against them at various locations across Toronto's downtown on June 26. One man had his arm broken in an interaction with an officer, while another two suffered facial fractures.
The SIU concluded that officers were not at fault for four of the incidents, citing either a lack of evidence to support the theory that excessive force was used, or an inability to determine how exactly the complainants sustained their injuries.
"It's been my experience here … that the SIU does a thorough, complete and impartial investigation," Frank Phillips, a spokesman for the SIU, told CBC News.
"If the evidence isn't there, the charge is not going to be laid."
But the agency concluded that it is probable excessive force was used in the case of two men who suffered facial fractures at a protest at Queen's Park.
Subject officers decline interview
Adam Nobody, 27, was running from officers in riot gear who were advancing upon him at the Queen's Park protest, the SIU said.
He was tackled by the officers and arrested in an incident that demonstrates "probable excessive use of force by an unidentified police officer," Ian Scott, the director of the agency, said in a statement.
"The arm of one of the officers can be seen moving very quickly two or three times in a striking motion toward the complainant with a closed fist in the upper area of either his body or head. If one or more of those blows landed in the complainant's facial area, it would be consistent with the injury he received," he said.
Identification controversy
SIU spokesman Frank Phillips said he couldn't say whether any of the officers involved in any of the six complaints were wearing identification.
About 90 Toronto police officers face disciplinary action for not wearing ID badges during the G20 summit.
"It is unknown whether any of the involved officers in these cases were wearing their name tags, nor is it clear on the evidence whether if they were wearing their name tags, it would have made any difference on the question of investigation given the volatility and the dynamics of the situation," Phillips said.
The SIU said it designated two officers as the subject of its investigation. Both declined to be interviewed in the investigation, as they are legally entitled to do. In total, the SIU interviewed eight officers and one civilian witness in its investigation.
The arrest is also captured in a YouTube video. But Scott said "it is impossible from the video to identify the officer who delivered these blows. They are all wearing largely identical clothing with helmets, and the video is taken from too great a distance to be of any assistance."
As the SIU was unable to determine exactly which officer used excessive force, it is not proceeding with a criminal investigation.
Arrested while helping fallen woman
Brendan Latimer, 19, was also at the Queen's Park protest and, like Nobody, suffered a facial fracture in the melee.
Latimer was knocked to the ground while helping a young woman who had fallen, according to the SIU. Demonstrators were fleeing the area after police started advancing on them, the SIU said.
Latimer was trampled by some of the protesters, and was on the ground for 25 to 30 seconds before officers moved in to arrest him. He alleges one officer struck him in the face, causing a fracture.
After interviewing nine witness officers and one civilian witness, the SIU concluded "there are reasonable grounds to believe an officer used excessive force leading to injuries to the complainant," Scott said.
"However, given the fact that no subject officer can be named after a thorough investigation, I cannot form reasonable grounds that any identified officer committed a criminal offence in the circumstances of this case."
The SIU said it is not looking into any other cases of alleged assault by law enforcement officers. It is unclear whether the officers involved in any of the six incidents were members of the Toronto Police Service, or whether they were from one of the myriad other forces responsible for policing the summit.
Around 1,100 people were arrested over the course of the G20 weekend on June 26 and 27, but most of those detained were not charged. Around 140 people are still facing charges and six people have been convicted.
Another provincial body, the Office of the Independent Police Review Director, is investigating around 275 complaints about police conduct during the G20. That watchdog has not said when they expect their review to be completed.
No police charged for civilian G20 injuries: SIU
6 men lodged complaints
Last Updated: Thursday, November 25, 2010 | 6:01 PM ET
CBC News
The SIU says it has been unable to identify police officers it says used excessive force when arresting two men at a G20 protest on June 26 at Queen's Park in Toronto. (Canadian Press)
An Ontario police watchdog is not holding any officers accountable for separate incidents in which it says excessive force was likely used against two civilians at a G20 protest in Toronto.
The province's Special Investigations Unit, which probes police operations where civilians are hurt or killed, on Thursday released the results of its investigation into six complaints of police brutality during last June's G20 summit.
The six men in question all complained that they were injured when law enforcement officers used excessive force against them at various locations across Toronto's downtown on June 26. One man had his arm broken in an interaction with an officer, while another two suffered facial fractures.
The SIU concluded that officers were not at fault for four of the incidents, citing either a lack of evidence to support the theory that excessive force was used, or an inability to determine how exactly the complainants sustained their injuries.
"It's been my experience here … that the SIU does a thorough, complete and impartial investigation," Frank Phillips, a spokesman for the SIU, told CBC News.
"If the evidence isn't there, the charge is not going to be laid."
But the agency concluded that it is probable excessive force was used in the case of two men who suffered facial fractures at a protest at Queen's Park.
Subject officers decline interview
Adam Nobody, 27, was running from officers in riot gear who were advancing upon him at the Queen's Park protest, the SIU said.
He was tackled by the officers and arrested in an incident that demonstrates "probable excessive use of force by an unidentified police officer," Ian Scott, the director of the agency, said in a statement.
"The arm of one of the officers can be seen moving very quickly two or three times in a striking motion toward the complainant with a closed fist in the upper area of either his body or head. If one or more of those blows landed in the complainant's facial area, it would be consistent with the injury he received," he said.
Identification controversy
SIU spokesman Frank Phillips said he couldn't say whether any of the officers involved in any of the six complaints were wearing identification.
About 90 Toronto police officers face disciplinary action for not wearing ID badges during the G20 summit.
"It is unknown whether any of the involved officers in these cases were wearing their name tags, nor is it clear on the evidence whether if they were wearing their name tags, it would have made any difference on the question of investigation given the volatility and the dynamics of the situation," Phillips said.
The SIU said it designated two officers as the subject of its investigation. Both declined to be interviewed in the investigation, as they are legally entitled to do. In total, the SIU interviewed eight officers and one civilian witness in its investigation.
The arrest is also captured in a YouTube video. But Scott said "it is impossible from the video to identify the officer who delivered these blows. They are all wearing largely identical clothing with helmets, and the video is taken from too great a distance to be of any assistance."
As the SIU was unable to determine exactly which officer used excessive force, it is not proceeding with a criminal investigation.
Arrested while helping fallen woman
Brendan Latimer, 19, was also at the Queen's Park protest and, like Nobody, suffered a facial fracture in the melee.
Latimer was knocked to the ground while helping a young woman who had fallen, according to the SIU. Demonstrators were fleeing the area after police started advancing on them, the SIU said.
Latimer was trampled by some of the protesters, and was on the ground for 25 to 30 seconds before officers moved in to arrest him. He alleges one officer struck him in the face, causing a fracture.
After interviewing nine witness officers and one civilian witness, the SIU concluded "there are reasonable grounds to believe an officer used excessive force leading to injuries to the complainant," Scott said.
"However, given the fact that no subject officer can be named after a thorough investigation, I cannot form reasonable grounds that any identified officer committed a criminal offence in the circumstances of this case."
The SIU said it is not looking into any other cases of alleged assault by law enforcement officers. It is unclear whether the officers involved in any of the six incidents were members of the Toronto Police Service, or whether they were from one of the myriad other forces responsible for policing the summit.
Around 1,100 people were arrested over the course of the G20 weekend on June 26 and 27, but most of those detained were not charged. Around 140 people are still facing charges and six people have been convicted.
Another provincial body, the Office of the Independent Police Review Director, is investigating around 275 complaints about police conduct during the G20. That watchdog has not said when they expect their review to be completed.
Tuesday, November 23, 2010
MINDFULNESS
Breathe Away Pain
While resisting pain only makes suffering worse, mindfulness meditation can help chronic pain sufferers.
By Ferris Jabr
Pain is necessary. It alerts us to threats, teaches us to avoid future risks, and makes sure we don't forget to help ourselves heal. Our bodies have evolved instinctive reactions to pain and injury—accidentally brush your hand against a boiling kettle and your arm will retract reflexively before you even realize why. Our minds, too, respond to pain in a characteristic manner: ever notice how even a minor wound can dominate your thoughts?
But what if you could manipulate your natural response to pain in order to control and alleviate suffering? That approach—aided by a technique known as mindfulness meditation—holds great promise for those experiencing chronic pain.
Though pain usually serves a beneficial purpose, chronic pain—which persists far longer than the usual period for an injury or illness—is pathological. Close to 1 in 3 Americans suffers from chronic pain to varying degrees, according to Penny Cowan, founder and executive director of the American Chronic Pain Association. Headaches and pain from the lower back, cancer, and arthritis are among the more common afflictions.
In a June 2008 study published in The Journal of Pain, researchers at the University of Pittsburgh found that elderly individuals who suffer from chronic low back pain benefited from mindfulness meditation, experiencing less pain, better sleep, enhanced well-being, and improved quality of life. And a 2003 review in Clinical Psychology: Science and Practice found significant improvements in pain ratings and other medical and psychological symptoms across a decade of studies.
The basics of mindfulness meditation aren't as complicated as you may think. First, you should simply relax, while maintaining good posture. Then close your eyes and accept all sensations as they filter through you. Don't judge them, but rather focus on your breathing. If you get distracted, gently guide yourself back to the sound and rhythm of your own breathing. The aim is to achieve active and focused moment-by-moment awareness of your present experience.
If you are in chronic pain, you may worry that increasing your awareness could only amp up your suffering. But mindfulness meditation can actually help by redirecting your attention, Cowan says. Our instinct is to resist pain, but resistance only increases suffering. Mindfulness can relinquish your resistance, thereby lessening the experience of your pain.
Meditation can help you find "the spaces in between" all of your experiences, where you can be in the moment and not in the pain—or worries about the pain, or feelings of anxiety or sadness, says Lonnie Zeltzer, professor of pediatrics, anesthesiology, and psychiatry at UCLA's David Geffen School of Medicine, and director of the Pediatric Pain Program. "By sitting each day to meditate, your brain actually begins to quiet down; you begin to feel more equanimity, and the pain begins to lessen and move from foreground to background."
A few suggestions for mindfulness meditation:
Find a Good Spot
Location can influence your ability to meditate properly. Above all, choose a place where you feel comfortable. The less distracting and quieter it is, the better.
Sit Right
You may sit in a chair or on the ground, but sitting with your legs crossed and your back straight is best. Comfort is good; slouching isn't. Buddhists believe that erect posture strengthens the connection between mind and body.
Breathe!
Your primary goal is to maintain a focus on—and solely on—your own natural inhalation and exhalation. Not only does such focus anchor you to successful meditation, it helps relax your body and your mind.
Keep Re-Focusing
Inevitably, your thoughts are going to wander. It will be impossible to think only of your breathing. But that's perfectly fine. Simply return your focus each time you realize you've been distracted.
While resisting pain only makes suffering worse, mindfulness meditation can help chronic pain sufferers.
By Ferris Jabr
Pain is necessary. It alerts us to threats, teaches us to avoid future risks, and makes sure we don't forget to help ourselves heal. Our bodies have evolved instinctive reactions to pain and injury—accidentally brush your hand against a boiling kettle and your arm will retract reflexively before you even realize why. Our minds, too, respond to pain in a characteristic manner: ever notice how even a minor wound can dominate your thoughts?
But what if you could manipulate your natural response to pain in order to control and alleviate suffering? That approach—aided by a technique known as mindfulness meditation—holds great promise for those experiencing chronic pain.
Though pain usually serves a beneficial purpose, chronic pain—which persists far longer than the usual period for an injury or illness—is pathological. Close to 1 in 3 Americans suffers from chronic pain to varying degrees, according to Penny Cowan, founder and executive director of the American Chronic Pain Association. Headaches and pain from the lower back, cancer, and arthritis are among the more common afflictions.
In a June 2008 study published in The Journal of Pain, researchers at the University of Pittsburgh found that elderly individuals who suffer from chronic low back pain benefited from mindfulness meditation, experiencing less pain, better sleep, enhanced well-being, and improved quality of life. And a 2003 review in Clinical Psychology: Science and Practice found significant improvements in pain ratings and other medical and psychological symptoms across a decade of studies.
The basics of mindfulness meditation aren't as complicated as you may think. First, you should simply relax, while maintaining good posture. Then close your eyes and accept all sensations as they filter through you. Don't judge them, but rather focus on your breathing. If you get distracted, gently guide yourself back to the sound and rhythm of your own breathing. The aim is to achieve active and focused moment-by-moment awareness of your present experience.
If you are in chronic pain, you may worry that increasing your awareness could only amp up your suffering. But mindfulness meditation can actually help by redirecting your attention, Cowan says. Our instinct is to resist pain, but resistance only increases suffering. Mindfulness can relinquish your resistance, thereby lessening the experience of your pain.
Meditation can help you find "the spaces in between" all of your experiences, where you can be in the moment and not in the pain—or worries about the pain, or feelings of anxiety or sadness, says Lonnie Zeltzer, professor of pediatrics, anesthesiology, and psychiatry at UCLA's David Geffen School of Medicine, and director of the Pediatric Pain Program. "By sitting each day to meditate, your brain actually begins to quiet down; you begin to feel more equanimity, and the pain begins to lessen and move from foreground to background."
A few suggestions for mindfulness meditation:
Find a Good Spot
Location can influence your ability to meditate properly. Above all, choose a place where you feel comfortable. The less distracting and quieter it is, the better.
Sit Right
You may sit in a chair or on the ground, but sitting with your legs crossed and your back straight is best. Comfort is good; slouching isn't. Buddhists believe that erect posture strengthens the connection between mind and body.
Breathe!
Your primary goal is to maintain a focus on—and solely on—your own natural inhalation and exhalation. Not only does such focus anchor you to successful meditation, it helps relax your body and your mind.
Keep Re-Focusing
Inevitably, your thoughts are going to wander. It will be impossible to think only of your breathing. But that's perfectly fine. Simply return your focus each time you realize you've been distracted.
Monday, November 22, 2010
Fish respond to SSRIs??!
Solitary fish hit rock bottom
'Frozen' zebrafish may be first piscene model for human depression.
November 22, 2010 0
By David Cyranoski
Zebrafish that stop swimming when left without company are showing promise as the first fish model of a human mood disorder.
In 2005, when neurobiologist Herwig Baier of the University of California, San Francisco, was screening thousands of zebrafish for vision problems, he found one that seemed a bit "off." If alone, especially after repeated periods of isolation, the fish would "freeze": just sit at the bottom of the tank (see video). If fish that swum normally were put in the tank, the relatively inactive fish became normal and swam around too.
Baier looked at the genetic mutations in the "frozen" fish and found one in the glucocorticoid receptor, a protein that is found in almost every cell and that senses cortisol--a hormone involved in the stress response. In the normal response to a stressful situation, the hypothalamus in the brain sends corticotropin-releasing hormone (CRH) to the pituitary gland, which releases adrenocorticotropic hormone (ACTH) to the adrenal gland. The adrenal gland in turn produces cortisol. Cortisol then effectively reduces levels of ACTH and CRH, completing the normal response that allows both humans and zebrafish to deal with stress.
In the frozen fish, however, Baier found that levels of all three hormones--CRH, ACTH and cortisol--were higher than normal. He guessed that the animals were unable to respond properly to chronic stress--a problem that is known to trigger anxiety or depression in humans. On the basis of that diagnosis, he started putting the antidepressant fluoxetine (originally marketed as Prozac) in their water. After four days, they started swimming around normally. Other antidepressants and anxiolytics--drugs used to treat anxiety--also worked as a pick-me-up, he says. "There's a long literature on chronic stress being related to depression, but the causal link is unknown," says Baier. "Now we might be able to simulate this in fish and study it."
Mutant marvel
Discussing his results at the Society for Neuroscience meeting in San Diego, Calif., last week, Baier says his mutants could represent the first fish model for a mood disorder and be a useful screening model for drugs.
"The fact that the key elements of stress and stress response are conserved in zebrafish is exciting because of the many experimental advantages of that model organism," says chemical geneticist Randall Peterson of the Massachusetts General Hospital, Harvard Medical School, Charlestown.
Studies this year support the idea that zebrafish can model complex behavior. Earlier this year, Peterson and his collaborator, neuroscientist Alex Schier of Harvard University in Cambridge, Mass., published the first two small-molecule screens based on zebrafish behavior. The studies focused on motor behavior, not mood disorders, but the team found that certain classes of psychotropic drugs, such as the antidepressants known as monoamine oxidase inhibitors, had recognizable, characteristic effects on behavior. "So, the idea of discovering new therapeutic approaches for anxiety or depression may not be so far-fetched," says Peterson.
If that proves true, the finding could accelerate drug-discovery programs. Chemical biology and drug discovery usually depend on screens of cells in lab dishes, for example. "But much of biology can't be easily reduced to an in vitro assay. This is particularly true for nervous-system disorders, where a complex, integrated nervous system is essential for research," says Peterson. Filling thousands of tiny wells on lab plates with zebrafish larvae and dousing them with candidate drug molecules offers the best of both worlds--high-throughput screening in a living system. "When we discover a new small molecule, we have the advantage of knowing that it works in vivo," he says.
Larval question
Baier plans to do the same sort of screening for new antidepressants and anxiolytics using his "frozen" fish. But Peterson does sound a note of caution. Baier's experiments used adult fish, whereas most zebrafish screens use larvae. Using adult for screening would be expensive and laborious. Baier plans to use larval stages but he admits it is not clear yet whether the larval zebrafish will react in the same way as the adult mutants.
The model will also have to convince the pharmaceutical industry that fish depression has significant similarities with the condition in people. This has not always been the case with mice, which as mammals should be a closer match to humans. "Considering the challenges of using rodents, including genetically engineered mice, to validly model human psychiatric diseases, zebrafish probably have some way to go before they are accepted as a translational model," said conference delegate Jeffrey Kogan, a behavioral neuroscientist working within the pharma industry who studies psychiatric disease.
It might, however, just take some time to sink in. In an e-mail to Nature a few days later, Kogan said that zebrafish might be a useful model organism for psychiatric disease after all. The huge numbers of fish that can be used in such studies would, for example, give the zebrafish mutant an advantage over the mouse. "I may have to reconsider my opinion," he says.
'Frozen' zebrafish may be first piscene model for human depression.
November 22, 2010 0
By David Cyranoski
Zebrafish that stop swimming when left without company are showing promise as the first fish model of a human mood disorder.
In 2005, when neurobiologist Herwig Baier of the University of California, San Francisco, was screening thousands of zebrafish for vision problems, he found one that seemed a bit "off." If alone, especially after repeated periods of isolation, the fish would "freeze": just sit at the bottom of the tank (see video). If fish that swum normally were put in the tank, the relatively inactive fish became normal and swam around too.
Baier looked at the genetic mutations in the "frozen" fish and found one in the glucocorticoid receptor, a protein that is found in almost every cell and that senses cortisol--a hormone involved in the stress response. In the normal response to a stressful situation, the hypothalamus in the brain sends corticotropin-releasing hormone (CRH) to the pituitary gland, which releases adrenocorticotropic hormone (ACTH) to the adrenal gland. The adrenal gland in turn produces cortisol. Cortisol then effectively reduces levels of ACTH and CRH, completing the normal response that allows both humans and zebrafish to deal with stress.
In the frozen fish, however, Baier found that levels of all three hormones--CRH, ACTH and cortisol--were higher than normal. He guessed that the animals were unable to respond properly to chronic stress--a problem that is known to trigger anxiety or depression in humans. On the basis of that diagnosis, he started putting the antidepressant fluoxetine (originally marketed as Prozac) in their water. After four days, they started swimming around normally. Other antidepressants and anxiolytics--drugs used to treat anxiety--also worked as a pick-me-up, he says. "There's a long literature on chronic stress being related to depression, but the causal link is unknown," says Baier. "Now we might be able to simulate this in fish and study it."
Mutant marvel
Discussing his results at the Society for Neuroscience meeting in San Diego, Calif., last week, Baier says his mutants could represent the first fish model for a mood disorder and be a useful screening model for drugs.
"The fact that the key elements of stress and stress response are conserved in zebrafish is exciting because of the many experimental advantages of that model organism," says chemical geneticist Randall Peterson of the Massachusetts General Hospital, Harvard Medical School, Charlestown.
Studies this year support the idea that zebrafish can model complex behavior. Earlier this year, Peterson and his collaborator, neuroscientist Alex Schier of Harvard University in Cambridge, Mass., published the first two small-molecule screens based on zebrafish behavior. The studies focused on motor behavior, not mood disorders, but the team found that certain classes of psychotropic drugs, such as the antidepressants known as monoamine oxidase inhibitors, had recognizable, characteristic effects on behavior. "So, the idea of discovering new therapeutic approaches for anxiety or depression may not be so far-fetched," says Peterson.
If that proves true, the finding could accelerate drug-discovery programs. Chemical biology and drug discovery usually depend on screens of cells in lab dishes, for example. "But much of biology can't be easily reduced to an in vitro assay. This is particularly true for nervous-system disorders, where a complex, integrated nervous system is essential for research," says Peterson. Filling thousands of tiny wells on lab plates with zebrafish larvae and dousing them with candidate drug molecules offers the best of both worlds--high-throughput screening in a living system. "When we discover a new small molecule, we have the advantage of knowing that it works in vivo," he says.
Larval question
Baier plans to do the same sort of screening for new antidepressants and anxiolytics using his "frozen" fish. But Peterson does sound a note of caution. Baier's experiments used adult fish, whereas most zebrafish screens use larvae. Using adult for screening would be expensive and laborious. Baier plans to use larval stages but he admits it is not clear yet whether the larval zebrafish will react in the same way as the adult mutants.
The model will also have to convince the pharmaceutical industry that fish depression has significant similarities with the condition in people. This has not always been the case with mice, which as mammals should be a closer match to humans. "Considering the challenges of using rodents, including genetically engineered mice, to validly model human psychiatric diseases, zebrafish probably have some way to go before they are accepted as a translational model," said conference delegate Jeffrey Kogan, a behavioral neuroscientist working within the pharma industry who studies psychiatric disease.
It might, however, just take some time to sink in. In an e-mail to Nature a few days later, Kogan said that zebrafish might be a useful model organism for psychiatric disease after all. The huge numbers of fish that can be used in such studies would, for example, give the zebrafish mutant an advantage over the mouse. "I may have to reconsider my opinion," he says.
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