Severe bone damage from diseases, including extensive trauma, fractures, and bone tumors, cannot self-heal, while traditional surgical treatment may bring side effects such as infection, inflammation, and pain. As a new biomaterial with controllable mechanical properties and biocompatibility, hydrogel is widely used in bone tissue engineering (BTE) as a scaffold for growth factor transport and cell adhesion. In order to make hydrogel more suitable for the local treatment of bone diseases, hydrogel preparation methods should be combined with synthetic materials with excellent properties and advanced technologies in different fields to better control drug release in time and orientation. It is necessary to establish a complete method to evaluate the hydrogel’s properties and biocompatibility with the human body. Moreover, establishment of standard animal models of bone defects helps in studying the therapeutic effect of hydrogels on bone repair, as well as to evaluate the safety and suitability of hydrogels. Thus, this review aims to systematically summarize current studies of hydrogels in BTE, including the mechanisms for promoting bone synthesis, design, and preparation; characterization and evaluation methods; as well as to explore future applications of hydrogels in BTE.

The aim of this study was to investigate the potential capability of an alcalase-hydrolyzed corn protein and fractions with different molecular mass (Mm) to facilitate alcohol metabolism by activating hepatic alcohol dehydrogenase (ADH). Results showed that corn peptide (CP) fraction with Mm fewer than 1,000 Da (CP < 1,000) exhibited the highest activity to activate ADH in vitro. The fraction administration (200 mg/kg body weight) with Mm fewer than 5,000 Da (CP < 5,000) demonstrated maximum ability to decrease blood alcohol concentration (BAC) in mice. There was a 45.1% reduction in BAC compared with that of the control group. Moreover, there was a strong linear relationship between BAC elimination rate and hepatic ADH activation rate (r = 0.9961). CP's potent capability to facilitate alcohol metabolism could be mainly correlated with the activation of hepatic ADH by hydrophobic CP with low Mm. CP's ·OH scavenging activity may also have synergistic contribution to the oxidative stress release. PRACTICAL APPLICATIONS There is an ever increasing need of an agent that could protect liver from alcoholic liver disease (ALD). Corn peptide (CP) is a potential candidate, which can facilitate alcohol metabolism and prevent ALD. CP was obtained from corn gluten meal (CGM), which was a by-product of corn industry. It will broaden the application and increase the value of CGM. CP, especially those with low molecular mass, has been reported with many bioactive functions, which was isolated with potent hepatic alcohol dehydrogenase (ADH) activating abilities and free radical-scavenging capacities. In general, CP could become a safe and potent alcohol metabolism stimulator and hepatoprotective agent. It could be manufactured in various forms, such as powder, tinctures, tablet, capsule and syrup. The future applications of CP would be mostly as a medicine, supplement or functional foods.