# Silkworm Enzyme Hydrolysates Improve Memory in MCI Models via CREB-BDNF Signaling and Enhanced Brain Mitochondrial Function

## TL;DR

Enzyme-treated silkworm hydrolysates improve memory in mice by boosting brain cell energy and reducing stress, with a key compound identified for quality control.

## Contribution

Enzymatic hydrolysis of HongJam enhances cognitive benefits through CREB-BDNF signaling and mitochondrial function, with a novel dipeptide marker identified.

## Key findings

- GS-EHS improved memory at lower doses compared to non-hydrolyzed HongJam.
- GS-EHS activated CREB-BDNF signaling and enhanced mitochondrial activity in the brain.
- GS-EHS reduced oxidative stress and regulated cell death pathways in MCI models.

## Abstract

Background/Objectives: This study investigated whether enzymatic hydrolysis enhances the cognitive benefits of HongJam (steamed mature silkworms) and explored the underlying mechanisms. A marker compound of enzyme-treated HongJam was also identified to support quality control. Methods and Results: Mice were supplemented with Golden Silk HongJam (GS) or its enzyme hydrolysates (GS-EHS). Behavioral tests showed both improved fear-aggravated memory, with GS-EHS producing similar or greater effects at lower doses. GS-EHS activated the cyclic AMP response element binding protein/brain-derived neurotrophic factor signaling pathway and mitigated scopolamine-induced mitochondrial dysfunction by enhancing mitochondrial complex activity and ATP production. It also increased esterase activity, reduced reactive oxygen species, and modulated programmed cell death by suppressing apoptosis while promoting autophagy and unfolded protein response pathways. These changes led to reduced endoplasmic reticulum stress and neuroinflammation. Mass spectrometry identified glycine-tyrosine dipeptide as a potential bioactive marker. Conclusions: GS-EHS enhances cognitive function by improving mitochondrial activity, reducing oxidative stress, and regulating programmed cell death. Enzymatic hydrolysis appears to increase the bioavailability of active compounds, making GS-EHS effective at lower doses. The glycine–tyrosine dipeptide may serve as a marker compound for standardizing GS-EHS based on its cognitive-enhancing properties.