ABSTRACT
Neurodegenerative diseases are the main causes of death and morbidity among elderly people worldwide. From the pathological point of view, oxidative stress, neuroinflammation, mitochondrial damage and apoptosis are the causes of neuronal diseases, and play a harmful role in the process of neuronal cell death and neurodegeneration. The most common neurodegenerative diseases are Alzheimer's disease(AD) and Parkinson's disease(PD), and there is no effective treatment. The physiological role of active peptides in the human body is significant. Modern medical research has found that animal and plant peptides, natural peptides in human body, can act on the central nervous system, and their active components can improve learning and memory ability, and play the roles of antioxidation, anti-inflammation, anti-apoptosis and maintaining the structure and function of mitochondria. This review reviews the reports on neurodegenerative diseases such as AD and PD by active peptides from animals and plants and natural peptides from the human body, and summarizes the neuroprotective mechanism of peptides. A theoretical basis for further research and development of active peptides was provided by examining the research and application of peptides, which provided a theoretical basis for further research and development.
ABSTRACT
Oxidative stress is a state of imbalance between oxidant and antioxidant effects in the body, which is closely associated with aging and many diseases. Therefore, the development of antioxidants has become urgent. In this study, we isolated three polypeptides, G-6-Y, P-8-R, and F-10-W, from Eleutherococcus sessiliflorus (Rupr. & Maxim.) S. Y. Hu (E. sessiliflorus), based on the antioxidant and anti-aging properties of Eleutherococcus, and screened the most powerful free radical scavenging peptide P-8-R. Ultraviolet B (UVB)-induced oxidative stress damage in the skin was established to test the efficacy of P-8-R. In cellular experiments, P-8-R not only prevented oxidative stress damage in HaCaT cells, reduced intracellular reactive oxygen species levels, and inhibited the overexpression of matrix metalloproteinases but also inhibited apoptosis via the mitochondria-dependent apoptotic pathway; in animal experiments, P-8-R was able to prevent oxidative stress damage in the skin and reduce skin collagen loss by inhibiting the overexpression of MMPs to prevent mouse skin aging. In conclusion, the present study contributes to an in-depth understanding of the active compounds of Eleutherococcus, which is of great significance for the pharmacodynamic mechanism and industrial development of Eleutherococcus, and P-8-R is likely to become a potential antioxidant and anti-aging drug or skin care cosmetic in the future.
ABSTRACT
Currently, commercialized infliximab (IFX) has rapidly propelled the clinical treatment of IBD, however, its inherent attributes, such as off-target effects and rapid metabolism, severely limit practical applications. Moreover, high doses injection of IFX can result in IBD treatment failure, which may induce other side effects. In this study, an colon microenvironment-responsive hydrogel (AL/HA hydrogel), consisting of acid-resistant sodium alginate and colon-degraded and targeted hyaluronic acid, was constructed by simple Ca2+/Zn2+ cross-linking. The ion-mediated hydrogel exhibited the protective effect of gastrointestinal tract to avoid early drug leakage, while the inflammation environments showed well-controlled drug release and significant biodegradable behaviors. Additionally, oral hydrogel exhibited long-standing enteritis areas compared with normal mice. Therefore, hydrogel-assisted enteritis treatment has great potential in IBD as an oral agent. After that, IFX was packaged in hydrogel to fabricate a facile oral antibody delivery system to treat IBD. IFX-embedded hydrogel showed remarkable therapeutic effect on IBD compared with free IFX. Surprisingly, oral hydrogel below 7 times IFX achieve the same amount of IFX-infused treatment that will further help alleviate the drawbacks of IFX. Our work elaborated on the efficacy of oral AL/HA@IFX in IBD, providing a guarantee for the future of promoted clinical transformation.