Jeffrey Mogil | |
---|---|
Born | Jeffrey Steven Mogil August 24, 1966 Toronto, Ontario, Canada |
Alma mater | University of Toronto, UCLA |
Known for | Pain research, transdisciplinary research, sex differences |
Awards | Fellow of the Canadian Academy of Health Sciences, Fellow of the Royal Society of Canada, Distinguished Career Award of the Canadian Pain Society, Bennet Cohen Award from the International Council for Laboratory Animal Science, SGV Award, Frederick W.L. Kerr Basic Science Research Award and Elizabeth Narcessian Award for Outstanding Educational Achievement from the American Pain Society |
Scientific career | |
Fields | Neuroscience, neurogenetics |
Institutions | University of Illinois at Urbana–Champaign, McGill University |
Doctoral advisor | John Liebeskind |
Website | MOGILab.ca |
Jeffrey S. Mogil, FCAHS, FRSC (born August 24, 1966) is a Canadian neuroscientist and the E.P. Taylor Professor of Pain Studies and Distinguished James McGill Professor at McGill University. [1] He is known for his work in the genetics of pain, [2] for being among the first scientists to demonstrate sex differences in pain perception, [3] and for identifying previously unknown factors and confounds that affect the integrity of contemporary pain research. [4] He has an h-index of 100. [5]
Jeffrey Mogil was born in Toronto, Ontario, Canada. He obtained his B.Sc. (Hons.) from the University of Toronto, and his Ph.D. from the University of California, Los Angeles in 1993. Following a postdoctoral fellowship at Oregon Health Sciences University, he obtained a faculty position at the University of Illinois at Urbana-Champaign from 1996 to 2001 before moving to McGill University in 2001 as full professor.
Mogil and colleagues have published many papers detailing how the physiological mechanisms underlying pain perception differ by sex in laboratory rodents and humans, [6] and he was among the first to call for the inclusion of female rodents in biomedical research. [7] [8] He was the founding Co-Chair of the Special Interest Group in Sex, Gender and Pain at the International Association for the Study of Pain. His team showed in 2015 [9] that male and female mice were employing wholly different immune cells—microglia and T cells, respectively—in the spinal cord to process chronic pain. This finding was immediately influential within the scientific community [10] and widely covered in the media. [11] [12] [13] It was voted the #1 discovery of 2015 by Quebec Science magazine, [14] inspired an editorial in the New York Times, [15] was chosen as one of 10 milestones in pain research from 2000 BC to the present by Nature , [16] and was cited by funding agencies in Canada [17] and the United States [18] in support of new Sex as a Biological Variable policies.
Other notable sex difference findings from his group include a meta-analysis showing that women are more sensitive to pain than men; [19] morphine analgesia, stress-induced analgesia, and opioid-induced hyperalgesia are mediated by different neurochemical receptors in the two sexes (NMDA receptors and V1AR receptors in males, and MC1Rs in females) in male and female mice and humans; [20] [21] [22] [23] [24] male and female mice have equivalent variability in pain sensitivity; [8] pain variability is due to different genes in both sexes; [25] [26] [23] female mice are more sensitive to itch than male mice; [27] pain reduces sexual desire in male but not female mice; [28] sex differences in morphine analgesia may be mediated by T cells; [29] pain affects dominance hierarchy in male but not female mice; [30] and, male but not female mice and humans display classically conditioned pain hypersensitivity. [31]
For the past century, the measurement of pain in rodent biomedical research was considered complicated and imprecise, and many researchers suggested there is a mismatch between human clinical pain symptoms and established procedures in rodents. [32] [33] Based on the human Neonatal Facial Coding Scale, [34] which is itself based on the Facial Action Coding System, Mogil and colleagues developed the Mouse Grimace Scale [35] and the Rat Grimace Scale. The original findings were highly cited, [36] widely covered in the scientific press, [37] and Mogil was awarded the Bennet Cohen Award from the International Council for Laboratory Animal Science [38] and the SGV Award from the Swiss Laboratory Animal Science Association [39] for the finding. Grimace scales are now routinely used in institutional veterinary settings for the determination of post-operative pain in animals, and have been developed for 10 species: mice, rats, rabbits, cats, horses, cows, pigs, sheep, ferret, and seal. [40]
Mogil's laboratory has made a number of other advances in algesiometry or dolorimetry (i.e., pain testing in animals) including the development of an animal model of vulvodynia. [41] [42] [43]
Although a handful of controversial papers from the 1950s and 1960s had suggested that non-primate mammals might be capable of altruism, [44] [45] Mogil's group was the first to provide modern evidence that mice were capable of emotional contagion of pain, a form of empathy. [46] [47] They showed that mice display more pain behavior if they are tested in close proximity to other mice also in pain, but only if the two mice are familiar with each other. This finding, which was also widely covered in the press, [48] launched a renaissance of new research into the topic of rodent social abilities. [49]
Mogil's lab subsequently showed [50] that familiar (but not stranger) humans also demonstrate highly similar emotional contagion of pain, and that reduction of stress via metyrapone treatment or a shared social experience (playing the videogame Rock Band together) can elicit empathy in strangers. This study was covered in the popular press, [51] including an episode of the TED Radio Hour. [52]
Using both quantitative trait locus mapping and genetic association study (including GWAS) techniques, Mogil's laboratory has provided evidence for the involvement of over 25 genes with pain and analgesia. The most notable of these was the demonstration in 2003 [23] that the MC1R gene, most well known for its mutations causing red hair, [53] is associated with Κ-opioid analgesia in women but not men. This finding was featured in the popular press. [54] [55]
Mogil and colleagues revealed a number of previously unidentified factors affecting the conclusions drawn from biomedical experiments. In 1996, they demonstrated that the newly discovered orphan opioid peptide, orphanin FQ/nociception, did not produce hyperalgesia as originally reported, [56] [57] but rather was reversing the stress-induced analgesia resulting from the intracerebroventricular injection through which it was administered. [58] In 1999, they showed that different inbred strains of mice displayed very different pain sensitivity. [59]
Chief among these methodological confounds was the observation that mice display a stress response to the presence of nearby males of a number of mammalian species, including human male experimenters, [4] calling into question the results of thousands of studies in the animal literature when the sex of the experimenter was not controlled, an animal equivalent to the "sweaty t-shirt study" in humans. This finding led to torrent of media activity, with articles on the finding in The New York Times , [60] National Geographic , [61] The Atlantic , [62] The Economist , [63] The New Yorker , [64] Time , [65] and U.S. News & World Report , [66] among others, and radio appearances on NPR’s Science Friday, [67] BBC World Service’s “Newsday” [68] and CBC’s “As It Happens”. [69]
Dynorphins (Dyn) are a class of opioid peptides that arise from the precursor protein prodynorphin. When prodynorphin is cleaved during processing by proprotein convertase 2 (PC2), multiple active peptides are released: dynorphin A, dynorphin B, and α/β-neoendorphin. Depolarization of a neuron containing prodynorphin stimulates PC2 processing, which occurs within synaptic vesicles in the presynaptic terminal. Occasionally, prodynorphin is not fully processed, leading to the release of "big dynorphin". "Big dynorphin" is a 32-amino acid molecule consisting of both dynorphin A and dynorphin B.
5-HT receptors, 5-hydroxytryptamine receptors, or serotonin receptors, are a group of G protein-coupled receptor and ligand-gated ion channels found in the central and peripheral nervous systems. They mediate both excitatory and inhibitory neurotransmission. The serotonin receptors are activated by the neurotransmitter serotonin, which acts as their natural ligand.
Opioid receptors are a group of inhibitory G protein-coupled receptors with opioids as ligands. The endogenous opioids are dynorphins, enkephalins, endorphins, endomorphins and nociceptin. The opioid receptors are ~40% identical to somatostatin receptors (SSTRs). Opioid receptors are distributed widely in the brain, in the spinal cord, on peripheral neurons, and digestive tract.
The κ-opioid receptor or kappa opioid receptor, abbreviated KOR or KOP for its ligand ketazocine, is a G protein-coupled receptor that in humans is encoded by the OPRK1 gene. The KOR is coupled to the G protein Gi/G0 and is one of four related receptors that bind opioid-like compounds in the brain and are responsible for mediating the effects of these compounds. These effects include altering nociception, consciousness, motor control, and mood. Dysregulation of this receptor system has been implicated in alcohol and drug addiction.
The μ-opioid receptors (MOR) are a class of opioid receptors with a high affinity for enkephalins and beta-endorphin, but a low affinity for dynorphins. They are also referred to as μ(mu)-opioid peptide (MOP) receptors. The prototypical μ-opioid receptor agonist is morphine, the primary psychoactive alkaloid in opium and for which the receptor was named, with mu being the first letter of Morpheus, the compound's namesake in the original Greek. It is an inhibitory G-protein coupled receptor that activates the Gi alpha subunit, inhibiting adenylate cyclase activity, lowering cAMP levels.
The nociceptin opioid peptide receptor (NOP), also known as the nociceptin/orphanin FQ (N/OFQ) receptor or kappa-type 3 opioid receptor, is a protein that in humans is encoded by the OPRL1 gene. The nociceptin receptor is a member of the opioid subfamily of G protein-coupled receptors whose natural ligand is the 17 amino acid neuropeptide known as nociceptin (N/OFQ). This receptor is involved in the regulation of numerous brain activities, particularly instinctive and emotional behaviors. Antagonists targeting NOP are under investigation for their role as treatments for depression and Parkinson's disease, whereas NOP agonists have been shown to act as powerful, non-addictive painkillers in non-human primates.
The neuropeptide FF receptors are members of the G-protein coupled receptor superfamily of integral membrane proteins which bind the pain modulatory neuropeptides AF and FF. The Neuropeptide FF receptor family is a member of the G protein-coupled receptor superfamily containing two subtypes, NPFF1 and NPFF2, which exhibit a high affinity for Neuropeptide FF (NPFF) peptides. NPFF1 is broadly distributed in the central nervous system with the highest levels found in the limbic system and the hypothalamus. NPFF2 is present in high density, particularly in mammals in the superficial layers of the spinal cord where it is involved in nociception and modulation of opioid functions. These receptors participate to the modulation of opioid receptor function in the brain and spinal cord, and can either reduce or increase opioid receptor function depending which tissue they are released in, reflecting a complex role for neuropeptide FF in pain responses.
AM-1241 (1-(methylpiperidin-2-ylmethyl)-3-(2-iodo-5-nitrobenzoyl)indole) is a chemical from the aminoalkylindole family that acts as a potent and selective agonist for the cannabinoid receptor CB2, with a Ki of 3.4 nM at CB2 and 80 times selectivity over the related CB1 receptor. It has analgesic effects in animal studies, particularly against "atypical" pain such as hyperalgesia and allodynia. This is thought to be mediated through CB2-mediated peripheral release of endogenous opioid peptides, as well as direct activation of the TRPA1 channel. It has also shown efficacy in the treatment of amyotrophic lateral sclerosis in animal models.
Fish fulfill several criteria proposed as indicating that non-human animals experience pain. These fulfilled criteria include a suitable nervous system and sensory receptors, opioid receptors and reduced responses to noxious stimuli when given analgesics and local anaesthetics, physiological changes to noxious stimuli, displaying protective motor reactions, exhibiting avoidance learning and making trade-offs between noxious stimulus avoidance and other motivational requirements.
Pain negatively affects the health and welfare of animals. "Pain" is defined by the International Association for the Study of Pain as "an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage." Only the animal experiencing the pain can know the pain's quality and intensity, and the degree of suffering. It is harder, if even possible, for an observer to know whether an emotional experience has occurred, especially if the sufferer cannot communicate. Therefore, this concept is often excluded in definitions of pain in animals, such as that provided by Zimmerman: "an aversive sensory experience caused by actual or potential injury that elicits protective motor and vegetative reactions, results in learned avoidance and may modify species-specific behaviour, including social behaviour." Nonhuman animals cannot report their feelings to language-using humans in the same manner as human communication, but observation of their behaviour provides a reasonable indication as to the extent of their pain. Just as with doctors and medics who sometimes share no common language with their patients, the indicators of pain can still be understood.
The tail flick test is a test of the pain response in animals, similar to the hot plate test. It is used in basic pain research and to measure the effectiveness of analgesics, by observing the reaction to heat. It was first described by D'Amour and Smith in 1941.
The hot plate test is a test of the pain response in animals, similar to the tail flick test. Both hot plate and tail-flick methods are used generally for centrally acting analgesic, while peripherally acting drugs are ineffective in these tests but sensitive to acetic acid-induced writhing test.
A nociception assay evaluates the ability of an animal, usually a rodent, to detect a noxious stimulus such as the feeling of pain, caused by stimulation of nociceptors. These assays measure the existence of pain through behaviors such as withdrawal, licking, immobility, and vocalization. The sensation of pain is not a unitary concept; therefore, a researcher must be conscious as to which nociception assay to use.
Huda Akil is a Syrian-American neuroscientist whose research has contributed to the understanding of the neurobiology of emotions, including pain, anxiety, depression, and substance abuse. Akil and her colleagues are best known for providing the first physiological evidence for a role of endorphins in the brain and demonstrating that endorphins are activated by stress and can cause pain inhibition.
Buprenorphine/samidorphan is a combination formulation of buprenorphine and samidorphan which is under development as an add on to antidepressants in treatment-resistant depression (TRD).
Pain is an aversive sensation and feeling associated with actual, or potential, tissue damage. It is widely accepted by a broad spectrum of scientists and philosophers that non-human animals can perceive pain, including pain in amphibians.
The grimace scale (GS), sometimes called the grimace score, is a method of assessing the occurrence or severity of pain experienced by non-human animals according to objective and blinded scoring of facial expressions, as is done routinely for the measurement of pain in non-verbal humans. Observers score the presence or prominence of "facial action units" (FAU), e.g. Orbital Tightening, Nose Bulge, Ear Position and Whisker Change. These are scored by observing the animal directly in real-time, or post hoc from photographs or screen-grabs from videos. The facial expression of the animals is sometimes referred to as the pain face.
Anita Holdcroft is an Emeritus Professor of Anaesthetics at Imperial College London and Honorary Consultant at Chelsea and Westminster Hospital. She specialised in acute pain in women and was the first to study the changes that occur in the brain during parturition.
Ream Al-Hasani is a British neuroscientist and pharmacologist as well as an assistant professor of anesthesiology at Washington University in St. Louis. Al-Hasani studies the endogenous opioid system to understand how to target it therapeutically to treat addiction, affective disorders, and chronic pain.
Howard Lincoln Fields is an American neuroscientist and clinical neurologist with expertise in pain and in opioid pharmacology. He is currently professor of neurology and physiology emeritus at the University of California, San Francisco (UCSF).