Integrated design and application of stimuli-responsive metal-organic frameworks in biomedicine: current status and future perspectives.

In recent years, metal-organic frameworks (MOFs) have garnered widespread attention due to their distinctive attributes, such as high surface area, tunable properties, biodegradability, extremely low density, high loading capacity, diverse chemical functionalities, thermal stability, well-defined pore sizes, and molecular dimensions. Increasingly, biomedical researchers have turned their focus towards their multifaceted development. Among these, stimuli-responsive MOFs, with their unique advantages, have captured greater interest from researchers. This review will delve into the merits and drawbacks of both endogenous and exogenous stimuli-responsive MOFs, along with their application directions. Furthermore, it will outline the characteristics of different synthesis routes of MOFs, exploring various design schemes and modification strategies and their impacts on the properties of MOF products, as well as how to control them. Additionally, we will survey different types of stimuli-responsive MOFs, discussing the significance of various MOF products reported in biomedical applications. We will categorically summarize different strategies such as anticancer therapy, antibacterial treatment, tissue repair, and biomedical imaging, as well as insights into the development of novel MOFs nanomaterials in the future. Finally, this review will conclude by summarizing the challenges in the development of stimuli-responsive MOFs in the field of biomedicine and providing prospects for future research endeavors.

Integrated osteoimmunomodulatory strategies based on designing scaffold surface properties in bone regeneration.

Those who have used traditional biomaterials as bone substitutes have always regarded the immune response as an obstacle leading to implant failure. However, cumulative evidence revealed that blindly minimizing host immune reactions cannot induce successful bone regeneration. With the emergence of the new concept of osteoimmunology, the intimate mutual effects between the skeletal system and the immune system have been gradually recognized, promoting the innovation of biomaterials with osteoimmunomodulatory properties. By tuning the surface properties, biomaterials can precisely manipulate the osteoimmune environment favoring bone regeneration. In this review, we first reviewed the mutual effects between the skeletal system and the immune system to show the importance of immunomodulation on bone regeneration. Subsequently, we summarize the recent developments in surface modification strategies in terms of the surface physicochemical properties and surface coatings and explain how these modification strategies work.

Hyperforin improves post-stroke social isolation­induced exaggeration of PSD and PSA via TGF-ß.

Stroke survivors often experience social isolation, which can lead to post­stroke depression (PSD) and post­stroke anxiety (PSA) that can compromise neurogenesis and impede functional recovery following the stroke. The present study aimed to investigate the effects and mechanisms of post­stroke social isolation­mediated PSD and PSA on hippocampal neurogenesis and cognitive function. The effects of the natural antidepressant hyperforin on post­stroke social isolation­mediated PSD and PSA were also investigated. In the present study, a model of PSD and PSA using C57BL/6J male mice was successfully established using middle cerebral artery occlusion combined with post­stroke isolated housing conditions. It was observed that PSD and PSA were more prominent in the isolated mice compared with the pair­housed mice at 14 days post­ischemia (dpi). Mice isolated 3 dpi exhibited decreased transforming growth factor­ß (TGF­ß) levels and impairment of hippocampal neurogenesis and memory function at 14 dpi. Intracerebroventricular administration of recombinant TGF­ß for 7 consecutive days, starting at 7 dpi, restored the reduced hippocampal neurogenesis and memory function induced by social isolation. Furthermore, intranasal administration of hyperforin for 7 consecutive days starting at 7 dpi improved PSD and PSA and promoted hippocampal neurogenesis and memory function in the isolated mice at 14 dpi. The inhibition of TGF­ß with a neutralizing antibody prevented the effects of hyperforin. In conclusion, the results revealed a previously uncharacterized role of hyperforin in improving post­stroke social isolation­induced exaggeration of PSD and PSA and, in turn, promoting hippocampal neurogenesis and cognitive function via TGF­ß.