Boby Mathew1, Krishnamachari Srinivasan2, Johnson Pradeep2, Tinku Thomas3, Amit Kumar Mandal4. 1. Clinical Proteomics Unit, Division of Molecular Medicine, St. John's Research Institute, St. John's National Academy of Health Sciences, Bangalore, India. 2. Department of Psychiatry, St. John's Medical College and Hospital, St. John's National Academy of Health Sciences, Bangalore, India. 3. Division of Epidemiology and Biostatistics, St. John's Research Institute, St. John's National Academy of Health Sciences, Bangalore, India. 4. Clinical Proteomics Unit, Division of Molecular Medicine, St. John's Research Institute, St. John's National Academy of Health Sciences, Bangalore, India. Electronic address: amit@sjri.res.in.
Abstract
BACKGROUND: Altered cholesterol levels in body fluids and brain tissues have been shown to be associated with suicidal behaviour, violence and aggression. But the biological underpinnings of this association in the pathophysiology of suicide are not clear. Cholesterol plays a crucial role in maintaining the cellular membrane fluidity and alterations in cellular membrane fluidity may impair serotonergic neurotransmission in the central nervous system. METHODS: We measured plasma esterified cholesterol and platelet membrane fluidity using fluorescence anisotropy and estimated flow activation energy which is a measure of order of membrane lipid bilayer in patients with recent suicidal attempt and compared with age and gender matched controls. RESULTS: The plasma esterified cholesterol, platelet membrane fluidity and flow activation energy was found to be significantly lower in patients with recent suicidal attempts compared to controls. CONCLUSION: Altered levels of plasma esterified cholesterol which is in equilibrium with membrane cholesterol might have resulted in decreased membrane fluidity and an increase in the order of membrane lipid bilayer. This might impair the serotonergic neurotransmission, which has been implicated in the pathophysiology of suicide.
BACKGROUND: Altered cholesterol levels in body fluids and brain tissues have been shown to be associated with suicidal behaviour, violence and aggression. But the biological underpinnings of this association in the pathophysiology of suicide are not clear. Cholesterol plays a crucial role in maintaining the cellular membrane fluidity and alterations in cellular membrane fluidity may impair serotonergic neurotransmission in the central nervous system. METHODS: We measured plasma esterified cholesterol and platelet membrane fluidity using fluorescence anisotropy and estimated flow activation energy which is a measure of order of membrane lipid bilayer in patients with recent suicidal attempt and compared with age and gender matched controls. RESULTS: The plasma esterified cholesterol, platelet membrane fluidity and flow activation energy was found to be significantly lower in patients with recent suicidal attempts compared to controls. CONCLUSION: Altered levels of plasma esterified cholesterol which is in equilibrium with membrane cholesterol might have resulted in decreased membrane fluidity and an increase in the order of membrane lipid bilayer. This might impair the serotonergic neurotransmission, which has been implicated in the pathophysiology of suicide.