Sterilization is the process of killing all microorganisms, while disinfection is the process of killing or removing all kinds of pathogenic microorganisms except bacterial spores. Biomaterials involved in cell experiments, animal experiments, and clinical applications need to be in the aseptic state, but their physical and chemical properties as well as biological activities can be affected by sterilization or disinfection. Decellularized matrix (dECM) is the low immunogenicity material obtained by removing cells from tissues, which retains many inherent components in tissues such as proteins and proteoglycans. But there are few studies concerning the effects of sterilization or disinfection on dECM, and the systematic introduction of sterilization or disinfection for dECM is even less. Therefore, this review systematically introduces and analyzes the mechanism, advantages, disadvantages, and applications of various sterilization and disinfection methods, discusses the factors influencing the selection of sterilization and disinfection methods, summarizes the sterilization and disinfection methods for various common dECM, and finally proposes a graphical route for selecting an appropriate sterilization or disinfection method for dECM and a technical route for validating the selected method, so as to provide the reference and basis for choosing more appropriate sterilization or disinfection methods of various dECM.

Peripheral nerve injury has a high incidence and often leads to severe losses of sensory and motor functions in the afflicted limb. Autologous nerve grafts are widely accepted as the gold standard for peripheral nerve repair, but the presence of inherent drawbacks dramatically reduces their usability. Numerous tissue engineering nerve grafts are developed as alternatives of autologous nerve grafts, and a variety of cells and neurotrophic factors were introduced into these grafts for improvement. However, they are still difficult to obtain satisfactory clinical results. Peripheral nerve regeneration following injury remains a significant challenge for researchers and clinicians. Exosomes are extracellular membranous nanovesicles that are secreted by most cells. As the key players of intercellular communication, exosomes play a fundamental role in the physiological and pathological processes of the nervous system. Accumulating evidence has suggested that exosomes can exert neurotherapeutic effects via mediating axonal regrowth, Schwann cell activation, vascular regeneration, and inflammatory regulation. Exosomes are emerging as a promising approach for treating peripheral nerve injury. Furthermore, they also provide possibilities for enhancing the repair capacity of various nerve grafts. This review primarily highlights the regenerative effects of exosomes on peripheral nerve injury. The exosomes from distinct sources reported so far in literature are summarized to understand their roles in the process of nerve repair. Moreover, the challenges that must be addressed in their clinical transformation are outlined as well. This review also provides further insight into the potential application of exosomes for peripheral nerve repair. Keywords: Exosome, nerve regeneration, peripheral nerve injury, Schwann cell, axonal regrowth, inflammation, vascular regeneration.

Pharmacological stimulation of adipose tissue remodeling and thermogenesis to increase energy expenditure is expected to be a viable therapeutic strategy for obesity. Berberine has been reported to have pharmacological activity in adipose tissue to anti-obesity, while the mechanism remains unclear. Here, we observed that berberine significantly reduced the body weight and insulin resistance of high-fat diet mice by promoting the distribution of brown adipose tissue and thermogenesis. We have further demonstrated that berberine activated energy metabolic sensing pathway AMPK/SIRT1 axis to increase the level of PPARγ deacetylation, which leads to promoting adipose tissue remodeling and increasing the expression of the thermogenic protein UCP-1. These findings suggest that berberine that enhances the AMPK/SIRT1 pathway can act as a selective PPARγ activator to promote adipose tissue remodeling and thermogenesis. This study proposes a new mechanism for the regulation of berberine in adipose tissue and offers a great prospect for berberine in obesity treatment

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The objective of this study was to fabricate an acellular sheep periosteum and explore its potential application in guided bone regeneration. Sheep periosteum was collected and decellularized by a modified decellularization protocol. The effectiveness of cell removal was proved by hematoxylin and eosin and 4 0 ,6-diamidino-2-phenylindole staining, DNA quantitative test, and agarose gel electrophoresis. After decellularization, its microstructure was found to become more porous while the integrality of collagen fibers remained undamaged, and the contents of collagen and glycosaminoglycan were not decreased significantly. Biomechanical analysis showed that the elastic modulus was significantly declined, while the yield stress was not affected, probably due to the collagen integrality. In vitro study of CCK-8 assay demonstrated that the acellular periosteum not only had no toxic effect to the MC3T3-E1 cells, but benefited the cell proliferation to some degree. In vivo experiment of guided bone regeneration was performed using a rabbit cranial model.Micro-CT and histological results revealed that the acellular periosteum not only effectively prevented the ingrowth of fibrous connective tissues, but also potentially facilitated bone regeneration. In conclusion, acellular sheep periostea, with wider sources, less costs, and more convenient fabrication process, would have great potential in the employment for guided bone regeneration. K E Y W O R D S acellular periosteum, animal experiment, barrier membrane, extracellular matrix, guided bone regeneration