N-acetylcysteine Affects Electrical Activity in Brain
At the 65th Annual Scientific Convention of the Society of Biological Psychiatry, researcher Christian Carmeli reported that N-acetylcysteine (NAC, 2 gm/day for six months) increased electroencephalogram (EEG) synchrony over the frontal cortical and left temporal regions in patients with schizophrenia. The EEG measures the frequency and amplitude of electrical activity on both sides of the brain.
-N-Acetylcysteine_Structural_Formulae.png "N-Acetylcysteine")
N-Acetylcysteine
Editor’s note: These data provide a neurophysiological mechanism that could explain the positive effects of NAC previously observed by researcher Mike Berk and associates in both schizophrenia and bipolar disorders and published in Biological Psychiatry in 2008. NAC is both a glutathione precursor providing antioxidant effects and a modulator of hyper-responsive glutamate reactivity in the n. accumbens or ventral striatum, the reward area of the brain. In placebo-controlled studies NAC appears effective in treating cocaine, heroin, and gambling addiction, as well as trichotillomania (compulsive hair-pulling). These effects are thought to be related to NAC’s dampening of glutamate responses in the n. accumbens, which, along with the dorsal striatum, appears to mediate habit memory. Read more
Schizophrenia v. Bipolar Disorder: Different Risk Factors
Robin Murray gave a plenary presentation at the 65th Annual Scientific Convention of the Society of Biological Psychiatry this year, in which he indicated that the genetic risk for schizophrenia and other major mental disorders may be overestimated. He suggested that even in identical twins there are considerable differences in incidence of major psychiatric illnesses, and sharing an environment could further inflate the appearance of genetic risk.
Evidence of some genetic vulnerability factors, such as neuregulin, disbindin, DISC-1, zinc finger transcription factors, and neurexin, has been replicated. However, these genes appear to contribute only about 1% of the vulnerability to schizophrenia or bipolar illness. Copy number variations (CNVs, extra or missing copies of a gene, which may alter its activity) and gene micro-deletions (in which small bits of DNA are missing) have been found in about 5% of patients with schizophrenia, in some patients with autism and mental disabilities, but not in those with bipolar illness.
Murray emphasized the importance of psychosocial and neuromotor markers of neural development in determining risk of subsequent major psychiatric illness, rather than the relatively weak genetic effects. He cited the work of MacCabe (2009), who collected information from 907,000 individuals in Sweden. Their scholastic achievement at age 15?16 was rated, and hospitalizations for psychosis were recorded from age 17?31. Of the 315,000 followed for the long term, 493 developed schizophrenia and 208 developed bipolar disorder.
Predictors of cognitive and motor development in these two major psychiatric illnesses appeared to differ. In those who went on to develop schizophrenia, there was a slower rate of motor development, receptive language, and overall IQ in adolescence, while in those who went on to develop bipolar disorder, there was a faster rate of motor development, more language facility, and higher IQ in adolescence.
Oxytocin, the Social Affiliation Drug, Has Interesting Effects in Autism and Now Schizophrenia
In 2007, investigator E. Hollander from Mt. Sinai published data indicating that intranasal oxytocin was associated with increases in target behaviors in patients with autism.
Now a study by David Feifel of the University of California, San Diego presented at the 65th Annual Scientific Convention of the Society of Biological Psychiatry showed that patients with schizophrenia showed improvement in symptomatology and increases in the recognition of positive facial affect after oxytocin was added to their antipsychotics regimen. Morris Goldman of Northwestern University reported that patients with schizophrenia, who often make mistakes assessing fear on facial emotion recognition tests, described fewer faces as fearful after receiving intranasal oxytocin.
Editors note: These new findings are built on the pioneering preclinical work of Tom Insel. He found marked differences in oxytocin and its receptors in the brains of mountain voles (who are largely asocial) compared to prairie voles (who are highly social and form lifelong bonds with their mates). Although these oxytocin findings have not yet produced a treatment for any psychiatric syndrome, they illustrate the potential of general scientific findings to inform new approaches to human illnesses.
Aripiprazole (Abilify), the Atypical Atypical Antipsychotic
This is an overview of the drug aripiprazole.
Spectrum of Efficacy
Aripiprazole has now been approved for acute and maintenance treatment of pediatric patients with bipolar disorder from ages 10 to 17. It had already been approved for adult bipolar disorder, schizophrenia, and as an adjunctive treatment for acute unipolar depression inadequately responsive to antidepressants of the serotonin-selective class or the serotonin-norepinephrine reuptake inhibitor venlafaxine. Aripiprazole, along with risperidone, is one of only two drugs FDA-approved for the treatment of irritability in autism.
Read more
The N-acetylcysteine Story: A New Potential Therapy for Bipolar Illness and Substance Abuse
N-acetylcysteine (NAC), a readily available substance from health food stores, is able to reestablish glutamate homeostasis (regulation and balance) in the reward area of brain (the nucleus accumbens), reported Peter Kalivas of the University of South Carolina at the “Staging neuropsychiatric disorders: Implications for idiopathogenesis and treatment” meeting in Mojacar, Spain this past November. Kalivas reported that NAC appears to be effective across a spectrum of addictions, including cocaine, heroin, alcohol, cigarette smoking, and gambling.
How NAC works in the brain
Even more remarkably, NAC also appears to have positive effects in placebo-controlled studies in the treatment of patients with bipolar illness, report Mike Berk and colleagues, who are studying the same substance in Australia. Compared with placebo, patients taking adjunctive NAC showed improvement in all outcome measures, especially depression, after 3 and 6 months. In another article, also published in Biological Psychiatry in 2008, Berk’s research group demonstrated that NAC improved some negative symptoms of schizophrenia. NAC has also shown positive effects in trichotillomania and on nail-biting, suggesting that it has a variety of potential clinical uses in conditions associated with pathological compulsive behavioral patterns.
