Beneficial Effects of Glycine (Bioglycin) on Memory and Attention in Young and Middle-Aged Adults

Abstract

The N-methyl D-aspartate receptor complex is involved in the mechanism of long-term potentiation, which is thought to be the biological basis of learning and memory. This complex can be manipulated in a number of ways, one of which is through the strychnine-insensitive glycine receptor coagonist site. The effects of Bioglycin(Konapharma, Pratteln, Switzerland), a biologically active form of the amino acid glycine, were therefore studied in healthy students (mean age, 20.7 years) and middle-aged men (mean age, 58.9 years) with tests that measured attention, memory and mood, using a double-blind, randomized, crossover design. Compared with the young group, the middle-aged group had significantly poorer verbal episodic memory, focused, divided, and sustained attention; they also differed in their subjective responses at the end of testing. Bioglycin significantly improved retrieval from episodic memory in both the young and the middle-aged groups, but it did not affect focused or divided attention. However, the middle-aged men significantly benefited from Bioglycin in the sustained-attention task. The effects of Bioglycin differed from those of other cognitive enhancers in that it was without stimulant properties or significant effects on mood, and it primarily improved memory rather than attention. It is likely to be of benefit in young or older people in situations where high retrieval of information is needed or when performance is impaired by jet lag, shift work, or disrupted sleep. It may also benefit the impaired retrieval shown in patients with schizophrenia, Parkinson's disease, and Huntington's disease.

Presynaptic Glycine Receptors Influence Plasma Membrane Potential and Glutamate Release

“…Previous work has demonstrated that the consumption of high doses of glycine can improve memory in volunteers [40] and decrease mortality in stroke [41]. The neurochemical basis for this phenomenon is still unclear, but presynaptic effects of glycine which we described can contribute to its pharmacological action.…”

Behavioral and cognitive effects of the N-methyl-d-aspartate receptor co-agonist d-serine in healthy humans: Initial findings

“…Significant cognitive effects were neither observed following acute oral administration of 0.8 g/kg GLY (Palmer et al, 2008) or 50 mg D-cycloserine DCS (D'Souza et al, 2000) which acts as a partial NMDAR agonist. In contrast, 100 mg GLY sublingually (File et al, 1999) and oral administration of 1.2 g of the GLY precursor milacemide (Schwartz et al, 1991) were reported to improve performance of memory tasks in healthy subjects. Moreover, Onur et al (2010) and Kuriyama et al (2011) have recently shown that DCS (250 mg and 100 mg single doses) improve declarative and procedural learning, respectively.…”

Acute high-dose glycine attenuates mismatch negativity (MMN) in healthy human controls

“…However, to reduce the complexity of the current study, one single dose was utilised. The time of electrophysiological recording was chosen to coincide with the maximum glycine plasma concentration, which has been reported to peak at approximately 30-45 min (Truong and Fahn 1988;Gannon et al 2002) and cognitive and electrophysiological effects reported within this time window (File et al 1999). …”

“…One study has investigated the effects of intravenous glycine (0.1 or 0.2 g/kg) on healthy controls and failed to find an effect on behavioral measures, cognitive functioning, or acoustic startle response (D'Souza et al 2000). Several studies using drugs that stimulate glycine neurotransmission, for instance 0.1 g of Bioglycin (a biologically active form of glycine; File et al 1999) and 0.4 and 1.2 g of milacemide (a glycine precursor; Saletu and Grunberger 1984;Schwartz et al 1991), have demonstrated improvements in memory and vigilance tasks, while a subsequent study found no effects with 0.4 g of milacemide (Camp-Bruno and Herting 1994). Thus, we are not in a position to comment on the cognitive effects of high doses, as previously employed for AGT in patients with schizophrenia.…”