Increased severity of closed head injury or repetitive subconcussive head impacts enhances post-traumatic headache-like behaviors in a rat model

Introduction Posttraumatic headache is one of the most common, debilitating, and difficult symptoms to manage after a traumatic head injury. The development of novel therapeutic approaches is nevertheless hampered by the paucity of preclinical models and poor understanding of the mechanisms underlying posttraumatic headache. To address these shortcomings, we previously characterized the development of posttraumatic headache-like pain behaviors in rats subjected to a single mild closed head injury using a 250 g weight drop. Here, we conducted a follow-up study to further extend the preclinical research toolbox for studying posttraumatic headache by exploring the development of headache-like pain behaviors in male rats subjected to a single, but more severe head trauma (450 g) as well as following repetitive, subconcussive head impacts (150 g). In addition, we tested whether these behaviors involve peripheral calcitonin gene-related peptide signaling by testing the effect of systemic treatment with an anti-calcitonin gene-related peptide monoclonal antibody (anti-calcitonin gene-related peptide mAb). Methods Adult male Sprague Dawley rats (total n = 138) were subjected to diffuse closed head injury using a weight-drop device, or a sham procedure. Three injury paradigms were employed: A single hit, using 450 g or 150 g weight drop, and three successive 150 g weight drop events conducted 72 hours apart. Changes in open field activity and development of cephalic and extracephalic tactile pain hypersensitivity were assessed up to 42 days post head trauma. Systemic administration of the anti-calcitonin gene-related peptide mAb or its control IgG (30 mg/kg) began immediately after the 450 g injury or the third 150 g weight drop with additional doses given every 6 days subsequently. Results Rats subjected to 450 g closed head injury displayed an acute decrease in rearing and increased thigmotaxis, together with cephalic tactile pain hypersensitivity that resolved by 6 weeks post-injury. Injured animals also displayed delayed and prolonged extracephalic tactile pain hypersensitivity that remained present at 6 weeks post-injury. Repetitive subconcussive head impacts using the 150 g weight drop, but not a single event, led to decreased vertical rearing as well as cephalic and extracephalic tactile pain hypersensitivity that resolved by 6 weeks post-injury. Early and prolonged anti-calcitonin gene-related peptide mAb treatment inhibited the development of the cephalic tactile pain hypersensitivity in both the severe and repetitive subconcussive head impact models. Conclusions Severe head injury gives rise to a prolonged state of cephalic and extracephalic tactile pain hypersensitivity. These pain behaviors also develop following repetitive, subconcussive head impacts. Extended cephalic tactile pain hypersensitivity following severe and repetitive mild closed head injury are ameliorated by early and prolonged anti-calcitonin gene-related peptide mAb treatment, suggesting a mechanism linked to calcitonin gene-related peptide signaling, potentially of trigeminal origin.

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Enhanced post-traumatic headache-like behaviors and diminished contribution of peripheral CGRP in female rats following a mild closed head injury

Cephalalgia ◽

10.1177/0333102420907597 ◽

2020 ◽

Vol 40 (7) ◽

pp. 748-760 ◽

Cited By ~ 5

Author(s):

Dara Bree ◽

Kimberly Mackenzie ◽

Jennifer Stratton ◽

Dan Levy

Keyword(s):

Monoclonal Antibody ◽

Head Injury ◽

Closed Head Injury ◽

Calcitonin Gene Related Peptide ◽

Female Rats ◽

Related Peptide ◽

Increased Risk ◽

Calcitonin Gene ◽

Closed Head ◽

Post Traumatic

Introduction Females are thought to have increased risk of developing post-traumatic headache following a traumatic head injury or concussion. However, the processes underlying this susceptibility remain unclear. We previously demonstrated the development of post-traumatic headache-like pain behaviors in a male rat model of mild closed head injury, along with the ability of sumatriptan and an anti-calcitonin-gene-related peptide monoclonal antibody to ameliorate these behaviors. Here, we conducted a follow-up study to explore the development of post-traumatic headache-like behaviors and the effectiveness of these headache therapies in females subjected to the same head trauma protocol. Methods Adult female Sprague Dawley rats were subjected to a mild closed head injury using a weight-drop device (n = 126), or to a sham procedure (n = 28). Characterization of headache and pain related behaviors included assessment of changes in cutaneous cephalic and extracephalic tactile pain sensitivity, using von Frey monofilaments. Sensitivity to headache/migraine triggers was tested by examining the effect of intraperitoneal administration of a low dose of glyceryl trinitrate (100 µg/kg). Treatments included acute systemic administration of sumatriptan (1 mg/kg) and repeated systemic administration of a mouse anti-calcitonin gene-related peptide monoclonal antibody (30 mg/kg). Serum levels of calcitonin gene-related peptide were measured at baseline and at various time points post head injury in new cohorts of females (n = 38) and males (n = 36). Results Female rats subjected to a mild closed head injury developed cutaneous mechanical hyperalgesia, which was limited to the cephalic region and was resolved 4 weeks later. Cephalic pain hypersensitivity was ameliorated by treatment with sumatriptan but was resistant to an early and prolonged treatment with the anti-calcitonin gene-related peptide monoclonal antibody. Following the resolution of the head injury-evoked cephalic hypersensitivity, administration of glyceryl trinitrate produced a renewed and pronounced cephalic and extracephalic pain hypersensitivity that was inhibited by sumatriptan, but only partially by the anti-calcitonin gene-related peptide treatment. Calcitonin gene-related peptide serum levels were elevated in females but not in males at 7 days post head injury. Conclusions Development of post-traumatic headache-like pain behaviors following a mild closed head injury, and responsiveness to treatment in rats is sexually dimorphic. When compared to the data obtained from male rats in the previous study, female rats display a prolonged state of cephalic hyperalgesia, increased responsiveness to a headache trigger, and a poorer effectiveness of an early and prolonged anti-calcitonin gene-related peptide treatment. The increased risk of females to develop post-traumatic headache may be linked to enhanced responsiveness of peripheral and/or central pain pathways and a mechanism independent of peripheral calcitonin gene-related peptide signaling.

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Increased severity of closed head injury or repetitive subconcussive head impacts enhances post-traumatic headache-like behaviors in a rat model

10.1101/2020.03.14.979047 ◽

2020 ◽

Author(s):

Dara Bree ◽

Jennifer Stratton ◽

Dan Levy

Keyword(s):

Monoclonal Antibody ◽

Head Injury ◽

Head Trauma ◽

Closed Head Injury ◽

Male Rats ◽

Pain Hypersensitivity ◽

Head Impacts ◽

Pain Behaviors ◽

Closed Head ◽

Weight Drop

AbstractIntroductionPosttraumatic headache (PTH) is one of the most common, debilitating and difficult symptoms to manage after a traumatic head injury. The development of novel therapeutic approaches is nevertheless hampered by the paucity of preclinical models and poor understanding of the mechanisms underlying PTH. To address these shortcomings, we previously characterized the development of PTH-like pain behaviors in rats subjected to a single mild closed head injury using a 250 g weight drop. Here, we conducted a follow-up study to further develop this preclinical model by exploring the development of headache-like pain behaviors in male rats subjected to a single, but more severe head trauma (450 g) as well as following repetitive, subconcussive head impacts (150 g). In addition, we tested whether these behaviors involve peripheral CGRP signaling by testing the effect of systemic anti-CGRP monoclonal antibody (anti-CGRP mAb).MethodsAdult male Sprague Dawley rats (total n=138) were subjected to diffuse closed head injury using a weight-drop device, or a sham procedure. Three injury paradigms were employed: a single hit, using 450 g or 150 g weight drop, and three successive 150 g weight drop events conducted 72 hours apart. Changes in open field activity and development of headache-related cephalic and extracephalic mechanical pain hypersensitivity were assessed up to 42 days post head trauma. Treatment included systemic administration of a mouse anti-calcitonin-gene-related peptide monoclonal antibody (30 mg/kg.).ResultsRats subjected to 450 g closed head injury displayed an acute decrease in rearing and increased thigmotaxis, together with cephalic and extracephalic mechanical pain hypersensitivity that resolved by 6 weeks post-injury. Repetitive subconcussive head impacts using the 150 g weight drop, but not a single event, led to decreased vertical rearing as well as prolonged cephalic and extracephalic mechanical pain hypersensitivity. Early and prolonged anti-CGRP mAb treatment inhibited the development of the cephalic, but not extracephalic pain hypersensitivities in both the severe and repetitive subconcussive head impact models.ConclusionsWhen compared to the data obtained from male rats in the previous study, a more severe head injury gives rise to a prolonged state of cephalic and extracephalic hyperalgesia. Such enhanced headache-like behaviors also occur following repetitive, subconcussive head impacts. Extended headache-like behaviors following severe and repetitive mild closed head injury are ameliorated by early and prolonged anti-CGRP mAb treatment, suggesting a mechanism linked to peripheral CGRP signaling.

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Enhanced post-traumatic headache-like behaviors and diminished contribution of peripheral CGRP in female rats following a mild closed head injury

10.1101/865444 ◽

2019 ◽

Cited By ~ 1

Author(s):

Dara Bree ◽

Kimberly Mackenzie ◽

Jennifer Stratton ◽

Dan Levy

Keyword(s):

Monoclonal Antibody ◽

Head Injury ◽

Closed Head Injury ◽

Calcitonin Gene Related Peptide ◽

Systemic Administration ◽

Female Rats ◽

Related Peptide ◽

Increased Risk ◽

Calcitonin Gene ◽

Closed Head

AbstractIntroductionFemales are thought to have increased risk of developing posttraumatic headache (PTH) following a traumatic head injury, or concussion. However, the processes underlying this susceptibility remain unclear. We previously explored the development of PTH-like pain behaviors in a novel rat model of mild closed head injury, along with the ability of sumatriptan and an anti-calcitonin-gene-related peptide monoclonal antibody to ameliorate these behaviors. Here, we explored the development of PTH-like behaviors and the effectiveness of these headache therapies in females subjected to the same head trauma protocol.MethodsAdult female Sprague Dawley rats were subjected to a mild closed head injury using a weight-drop device. Characterization of headache and pain related behaviors included assessment of changes in cutaneous cephalic and extracephalic tactile pain sensitivity, using von Frey monofilaments. Sensitivity to headache/migraine triggers was tested by examining the effect of systemic administration of a low-dose of glyceryl trinitrate (GTN). Treatments included acute systemic administration of sumatriptan and repeated systemic administration of a mouse anti-calcitonin-gene-related peptide monoclonal antibody. Serum levels of calcitonin-gene-related peptide were measured at various time points in females and males after the head injury.ResultsFemale rats subjected to a mild closed head injury developed cutaneous mechanical hyperalgesia, that was limited to the cephalic region, and was resolved 4 weeks later. Cephalic pain hypersensitivity was ameliorated by treatment with sumatriptan, but was resistant to an early and prolonged treatment with the anti-CGRP monoclonal antibody. Following the resolution of the head injury-evoked cephalic hypersensitivity, administration of GTN produced a renewed and pronounced cephalic and extracephalic pain hypersensitivity that was inhibited by sumatriptan, but only partially by the anti-CGRP treatment. CGRP serum levels were elevated in females but not in males at 7 days post head injury.ConclusionsDevelopment of PTH-like pain behaviors following a mild closed head injury, and responsiveness to treatment in rats is sexually dimorphic. When compared to males, female rats display a prolonged state of cephalic hyperalgesia, increased responsiveness to a headache trigger, and a poorer effectiveness of an early and prolonged anti-CGRP treatment. The increased risk of females to develop PTH may be linked to enhanced responsiveness of peripheral and/or central pain pathways and a mechanism independent of peripheral CGRP signaling.

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Differences between open and closed head injury: evaluation of weight-drop model in experimental traumatic brain injury

Intrinsic Activity ◽

10.25006/ia.5.s2-a2.22 ◽

2017 ◽

Vol 5 (Suppl. 2) ◽

pp. A2.22

Author(s):

Einars Kupats

Keyword(s):

Traumatic Brain Injury ◽

Brain Injury ◽

Head Injury ◽

Closed Head Injury ◽

Closed Head ◽

Weight Drop ◽

Experimental Traumatic Brain Injury

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Closed Head Injury Triggers Early Production of TNFα and IL-6 by Brain Tissue

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1994.76 ◽

1994 ◽

Vol 14 (4) ◽

pp. 615-619 ◽

Cited By ~ 257

Author(s):

E. Shohami ◽

M. Novikov ◽

R. Bass ◽

A. Yamin ◽

R. Gallily

Keyword(s):

Head Injury ◽

Brain Tissue ◽

Closed Head Injury ◽

Prostaglandin E ◽

Normal Brain ◽

Necrosis Factor Alpha ◽

Local Inflammatory Response ◽

Closed Head ◽

Weight Drop ◽

Early Production

In a model of closed head injury (CHI) in the rat we have shown the activation of phospholipase A2 and the production of eicosanoids after injury: at 15 min, mainly 5-hydroxyeicosatetraenoic acid (5-HETE), and at 24 h, mainly prostaglandin E2. The present study was designed to test whether CHI can also trigger the production of cytokines in the brain. CHI was induced in ether-anesthesized rats by a weight-drop device falling over the exposed skull covering the left hemisphere, 1–2 mm lateral to the midline in the midcoronal plane. In the posttraumatic period (1–24 h), the rats were decapitated, cortical tissue from the injured zone of the contused and contralateral hemispheres was removed and sonicated, and cytokine activity was assessed. Whereas no tumor necrosis factor alpha (TNFα) activity was found in normal brain tissue, it was detectable in the contused hemisphere (∼72 ± 50 pg/mg protein) as early as 1 h post-CHI. TNFα levels increased at 2 h, peaked at 4 h, (-609 ± 540 pg/mg protein), and declined thereafter. At parallel intervals, only low levels of TNFα were detected in the contralateral hemisphere. In normal brain, interleukin-6 (IL-6) was nondetectable. Following CHI, high levels of IL-6 were present, although their accumulation lagged behind that of TNFα by 2–4 h, peaking at 8 h (62 ± 31 ng/mg protein). We suggest that the rapid production of TNFα and IL-6 following CHI is a local inflammatory response of brain tissue to primary insult.

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