Effect of Anserine/Carnosine Supplementation on Verbal Episodic Memory in Elderly People

Abstract

Our goal in this study was to determine whether or not anserine/carnosine supplementation (ACS) is capable of preserving cognitive function of elderly people. In a double-blind randomized controlled trial, volunteers were randomly assigned to an ACS or placebo group at a 1:1 ratio. The ACS group took 1.0 g of an anserine/carnosine (3:1) formula daily for 3 months. Participants were evaluated by psychological tests before and after the 3-month supplementation period. Thirty-nine healthy elderly volunteers (60–78 years old) completed the follow-up tests. Among the tests, delayed recall verbal memory assessed by the Wechsler Memory Scale-Logical Memory showed significant preservation in the ACS group, compared to the placebo group (p = 0.0128). Blood analysis revealed a decreased secretion of inflammatory cytokines, including CCL-2 and IL-8, in the ACS group. MRI analysis using arterial spin labeling showed a suppression in the age-related decline in brain blood flow in the posterior cingulate cortex area in the ACS group, compared to the placebo group (p = 0.0248). In another randomized controlled trial, delayed recall verbal memory showed significant preservation in the ACS group, compared to the placebo group (p = 0.0202). These results collectively suggest that ACS may preserve verbal episodic memory and brain perfusion in elderly people, although further study is needed.

Important roles of dietary taurine, creatine, carnosine, anserine and 4-hydroxyproline in human nutrition and health

“…For example, oral administration of anserine (10 or 100 mg/45 kg BW in 20 ml of tap water) reduced blood glucose levels during an oral glucose tolerance test in humans . Similarly, supplementing anserine plus carnosine (1 g/day, 3:1 ratio, 3 months) to healthy elderly subjects has been shown to preserve verbal episodic memory and brain perfusion (including blood flow in the prefrontal brain (Ding et al 2018;Hisatsune et al 2015;Rokicki et al 2015), attenuate cognitive impairment (Hisatsune et al 2016;Masuoka et al 2019), inhibit the production of inflammatory cytokines by peripheral blood mononuclear cells (Katakura et al 2017), and enhance muscular strength and exercise endurance (Hirohiko et al 2006). Because avian muscle contains a large amount of anserine as noted previously, much evidence shows that consumption of a popular Asian food known as chicken essence (chicken meat extract) by humans, particularly elderly subjects, has long been a nutritional means to improve human health and prevent chronic diseases.…”

Carnosine and the processes of ageing

“…insulin resistance (2 g/daily for 12 weeks, humans) [21], diabetic kidney disease (60 mg/kg for 20 weeks, rodents) [22], atherosclerosis (2 g/l drinking water for 20 weeks, rodents) [23], Alzheimer's disease (AD) (10 mM, in vitro) [24], Parkinson's disease (1.5 g for 30 days, humans) (PD) [25], and wound healing (100 mg/kg for 12 days, rodents) [26]. It is also interesting to note that in humans dietary supplementation with carnosine has produced beneficial outcomes in various aspects of behaviour and well-being [27][28][29][30][31][32]. Although such phenomenology does not provide any insight into the actual mechanistic route by which the dipeptide induces these effects, these observations nevertheless indicate that dietary carnosine can influence the brain despite the presence of serum carnosinase.…”

“…Supplementation with carnosine has been shown to have anti-inflammatory, antioxidant, antiglycation and chelating roles, and may act as a buffering agent in skeletal muscle and improve calcium handling [9][10][11][12]. Although circulating carnosine levels are affected by the presence of plasma carnosinase in humans [7], long-term supplementation of carnosine results in improved health and/or behavioural outcomes (27)(28)(29)(30)(31)(32). Therefore, it could be speculated that chronic supplementation maintains a more constant plasma level of carnosine mainly due to saturation of carnosinase.…”

Mechanisms of carnosine-induced activation of neuronal cells

“…We previously demonstrated that carnosine and anserine supplementation is capable of preserving cognitive function in elderly people using a double-blind randomized controlled trial [3]. Therefore, carnosine is expected to be recognized as a useful functional food factor.…”

“…Chicken breast meat contains large amounts of imidazole dipeptide (IDP) (about 1% of chicken breast meat), of which carnosine (β-alanyl-L-histidine) and its derivative anserine (β-alanyl-1-methyl-L-hisitidine) are two types. IDP is known to have an anti-fatigue effect [1], to induce anti-depressant-like activity in rats [2], and to enhance memory function in elderly people [3]. Among IDPs, much research has focused on establishing the many functions of carnosine [4][5][6][7].…”