Hydrolyzed Chicken Extract (ProBeptigen®) on Cognitive Function in Healthy Middle-Aged People: A Randomized Double-Blind Trial

Dean Wu, Cheng-Chang Yang, Kuan-Yu Chen, Ying-Chin Lin, Pei-Jung Wu, Pei-Hsiu Hsieh, Yoshihiro Nakao, Mandy Y L Ow, Yi-Chen Hsieh, Chaur-Jong Hu, Dean Wu, Cheng-Chang Yang, Kuan-Yu Chen, Ying-Chin Lin, Pei-Jung Wu, Pei-Hsiu Hsieh, Yoshihiro Nakao, Mandy Y L Ow, Yi-Chen Hsieh, Chaur-Jong Hu

Abstract

Cognitive decline is an important issue of global public health. Cognitive aging might begin at middle adulthood, the period particularly vulnerable to stress in lifespan. Essence of chicken (EOC) has consistently demonstrated its beneficial effects on various cognitive domains as nutritional supplementation. This study primarily aimed to examine the cognitive enhancement effects of ProBeptigen® (previously named CMI-168), hydrolyzed peptides extracted from EOC, in healthy middle-aged people under mild stress. Ninety healthy subjects were randomly assigned into the ProBeptigen® or placebo group for eight weeks. Neurocognitive assessment, event-related potentials (ERPs), and blood tests were conducted before, during, and after the treatment. The ProBeptigen® group outperformed placebo group on Logical Memory subtests of Wechsler Memory Scale-third edition (WMS-III) and Spatial Working Memory task in the Cambridge Neuropsychological Test Automated Battery (CANTAB). The anti-inflammatory effects of ProBeptigen® in humans were also confirmed, with progressively declining high-sensitivity C-reactive protein (hs-CRP) levels. Regular dietary supplementation of ProBeptigen® is suggested to improve verbal short- and long-term memory as well as spatial working memory, and reduce inflammation in middle-aged healthy individuals with stress. The effects of ProBeptigen® on cognition warrant further investigation. (NCT03612752).

Keywords: cognitive decline; dietary supplements; essence of chicken.

Conflict of interest statement

Y Nakao and M Ow are employees of BRAND’S Suntory Asia. Other authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Figures

Figure 1
Figure 1
The study protocol. CANTAB, Cambridge Neuropsychological Test Automated Battery; The symbol of “+” denotes the examination performed at that visit. NP, neuropsychological; PSS, Perceived Stress Scale; P300, event-related potential.
Figure 2
Figure 2
The flowchart of this clinical trial.
Figure 3
Figure 3
Results from Logical Memory and Family Pictures subtests of the Wechsler Memory Scale-3rd edition. (A) Logical Memory I, (B) Family Pictures I, (C) Logical Memory II, (D) Family Pictures II, (E) Thematic score of Logical Memory I, (F) Thematic score of Logical Memory II. The unit of the Y-axis is scaled score. Error bars represent standard errors. The p-value shown in each diagram denotes the statistics of time × treatment interaction after considering the baseline data as a covariate. Higher scores indicate better performance.
Figure 4
Figure 4
CANTAB including (A) spatial working memory (SWMBE468) and (B) reaction time task median five-choice reaction time (RTIFMDRT) results. Error bars represent standard errors. The p-value shown in each diagram denotes the statistics of time × treatment interaction after considering the baseline data as a covariate. Lower scores indicate better performance.
Figure 5
Figure 5
Results of perceived stress, depression, anxiety and sleep quality measurements. (A) Perceived Stress Score (PSS), (B) Beck Depression Inventory-II (BDI), (C) Pittsburg Sleep Quality Index (PSQI), (D) State-Trait Anxiety Inventory–trait anxiety (STAI-T), (E) STAI-S, State-Trait Anxiety Inventory–state anxiety (STAI-S). Error bars represent standard errors. The p-value shown in each diagram denotes the statistics of time × treatment interaction after considering the baseline data as a covariate. Lower scores indicate fewer symptoms.
Figure 6
Figure 6
Changes of biochemistry profiles. (A) Glucose, (B) Estimated glomerular filtration rate (eGFR), (C) Creatinine, (D) Blood urea nitrogen (BUN), (E) Triiodothyronine (T3), (F) Thyroid-stimulating hormone (TSH), (G) Free thyroxine (Free T4), (H) Cortisol, (I) Alanine transaminase (ALT), (J) Aspartate aminotransferase (AST), (K) High-sensitivity C-reactive protein (hs-CRP). Error bars represent standard errors. The p-value shown in each diagram denotes the statistics of time × treatment interaction after considering the baseline data as a covariate and the asterisk denotes a statistically significant between-group difference at the specific visit time.
Figure 7
Figure 7
Results of event-related potentials. (A) Latency of positive event-related potentials at 300 ms (P300-L), (B) Amplitude of positive event-related potentials at 300 ms (P300-A). Error bars represent standard errors. The p-value shown in each diagram denotes the statistics of time × treatment interaction after considering the baseline data as a covariate.

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