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Laurie A Kellaway

Publications and source records attributed to Laurie A Kellaway.

4 recordsLinked to original sources

Herbal complement inhibitors in the treatment of neuroinflammation: future strategy for neuroprotection.

The upregulated complement system plays a damaging role in disorders of the central nervous system (CNS). The classical and alternate pathways are two major pathways activated in neuroinflammatory disorders such as Alzheimer's disease, multiple sclerosis, traumatic brain injury, spinal cord injury, HIV-associated dementia, Parkinson's disease, and mad cow disease. Failure of currently available anti-inflammatory agents, especially cyclooxygenase inhibitors, in offering significant neuroprotection in large epidemiologic clinical trials of CNS disorders suggests an urgent need for the development of new neuroprotective agents. The positive preclinical outcomes in treating CNS disorders by complement regulatory molecules, such as vaccinia virus complement control protein, suggest the possibility of using complement-inhibitory molecules as neuroprotective agents. Several active ingredients of herbal origin are found to have complement-inhibitory activity. These herbal ingredients along with other anti-inflammatory roles might be useful in treating neuroinflammation associated with CNS disorders. Active ingredients of herbal origin with complement inhibitory ingredients are summarized and classified according to their chemical nature and specificity towards the major pathways activating the complement system. The structure activity relationship of some specific examples is also discussed in this report. This information might be helpful in formulating a natural panacea against complement-mediated neuroinflammation.

Complement Inactivating Agents↗

Administration of vaccinia virus complement control protein shows significant cognitive improvement in a mild injury model.

Previous studies have shown that traumatic mild brain injury in a rat model is accompanied by breakdown of the blood brain barrier and the accumulation of inflammatory cells. A therapeutic agent, vaccinia virus complement control protein (VCP), inhibits both the classic and the alternative pathways of the complement system and, in so doing, prevents cell death and inflammation. With the use of a rat mild injury model, the effects of VCP on spatial learning and memory were tested. Training in a Morris water maze consisted of a total of 16 trials over a 2-day period before rats were anesthetized and subjected to mild (1.0-1.1 atm) lateral fluid percussion injury (FPI) 3.0 mm lateral to the sagittal suture and 4.5 mm posterior to bregma. Ten microl of VCP (1.7 mg/ml) was injected into the injury site immediately after FPI. Two weeks post-FPI the rats were assessed in the Morris water maze for spatial learning and memory. Neurologic motor function tests were carried out after FPI for 14 consecutive days and again after 28 days. The Morris water maze data show that FPI plus saline-injected rats spent a significantly (P <0.05) larger amount of time in one of the incorrect quadrants than did the FPI plus VCP-injected group. Neurologic evaluations 24 hours postinjury revealed differences in sensorimotor function between groups. The results suggest that in a mild injury model, VCP influences neurologic outcome and offers some enhancement in spatial memory and learning.

Animals↗

Neuroprotection from complement-mediated inflammatory damage.

Several neurodegenerative disorders, such as multiple sclerosis, Alzheimer's disease, and Parkinson's disease, are associated with inflammatory damage. The complex process of neuroinflammation involves various components of the immune system and the central nervous system. Particularly, brain astrocytes and microglial cells generate several inflammatory mediators like cytokines, leukotrienes, superoxide radicals, eicasonoids, and the components of the complement cascade. Complement plays an important role in the etiology of most of the neuroinflammatory disorders. To prevent long-term dysfunction inflammation in the central nervous system must be modulated with neuroprotective agents such as nonsteroidal anti-inflammatory drugs, steroids, phenolic thiazoles, nitrones, catechins, nitric oxide synthetase inhibitors, flavonoids, and phosphodiesterase inhibitors. Few drugs are found to be effective and their therapeutic benefit is hampered by side effects. Most of the neuroprotective agents are free radical scavengers and many inhibit only one or two aspects of inflammation. The complement inhibitory activity of most of these agents is either unknown or not established. Thus, there is doubt regarding their therapeutic value in most of the inflammatory disorders in which complement plays a major role. In this context the role of a multifunctional protein, vaccinia virus complement control protein (VCP), is quite significant as it may play a pivotal role in the treatment of several neuroinflammatory disorders. VCP is known to inhibit both complement pathways involved in inflammation. It is also known to inhibit cytokines and chemokines in inflammation. Our recent studies on rats demonstrate that VCP administration inhibits macrophage infiltration, reduces spinal cord destruction, and improves motor skills associated with spinal cord injury, establishing VCP as a strong candidate for neuroprotection. Thus, complement inhibitors such as VCP can serve as neuroprotective agents in inflammation associated with several neurodegenerative disorders.

Animals↗

Molecular mechanisms, emerging etiological insights and models to test potential therapeutic interventions in Alzheimer's disease.

Alzheimer's disease (AD) is a common cause of dementia, resulting from accumulated beta-amyloid protein deposits in the brain. As the population ages the incidence of AD is also on the rise. The incidence is very high in the developed countries where life expectancy is high, but it is also rising rapidly in the developing countries. Caring for patients suffering from AD is a major economic burden. The mechanisms underlying the neuropathology of AD are slowly being unravelled. Here we explore the many models and theories, which have been proposed over the years. We then discuss a potential therapeutic agent, vaccinia virus complement control protein (VCP), involved in modulating the complement system in AD. VCP has been shown in in vitro studies to block the complement activation caused by the beta peptide. Traumatic injuries to the brain are well known risk factors associated with the development of AD. VCP can also enhance functional recovery resulting from traumatic brain injury and may be able to slow the progression of traumatic brain injury to AD. Here we describe strategies for testing this hypothesis and evaluating other agents such as VCP.

Alzheimer Disease↗