The disease of osteoporosis is characterized by impaired bone structure and an increased risk of fractures. There is a significant impact of cytokines and hormones on bone homeostasis and the diagnosis of osteoporosis. As defined by the World Health Organization (WHO), osteoporosis is defined as having a bone mineral density (BMD) that is 2.5 standard deviations (SD) or more below the average for young and healthy women (T score < −2.5 SD). Cytokines and hormones, particularly in the remodeling of bone between osteoclasts and osteoblasts, control the differentiation and activation of bone cells through cytokine networks and signaling pathways like the nuclear factor kappa-B ligand (RANKL)/the receptor of RANKL (RANK)/osteoprotegerin (OPG) axis, while estrogen, parathyroid hormones, testosterone, and calcitonin influence bone density and play significant roles in the treatment of osteoporosis. This review aims to examine the roles of cytokines and hormones in the pathophysiology of osteoporosis, evaluating current diagnostic methods, and highlighting new technologies that could help for early detection and treatment of osteoporosis.

The vulnerability of skin wounds has made efficient wound dressing a challenging issue for decades, seeking to mimic the natural microenvironment of cells to facilitate cell binding, augmentation, and metamorphosis. Many three-dimensional (3D) bioprinted hydrogel-based configurations have been developed using high-tech devices to overcome the limitations of traditional dressing materials. Based on a material perspective, this review examines current state-of-the-art 3D bioprinting for hydrogel-based dressings, including both their advantages and limitations. Accordingly, their potential applications in terms of their performance in vitro and in vivo, as well as their adaptability to clinical settings, were investigated. Moreover, different configurations of 3D bioprinters are discussed. Finally, a roadmap for advancing wound dressings fabricated with 3D bioprinting is presented.

Chronic wounds represent a growing clinical and economic burden, and their impaired healing is closely linked to a disrupted redox environment. Reactive oxygen species (ROS) are essential signaling molecules that regulate each phase of wound healing, from hemostasis and inflammation through proliferation and remodeling. ROS at physiological levels regulate antimicrobial defense, angiogenesis and cellular migration. However, the persistent oxidative overload that characterizes chronic wounds sustains inflammation and delays tissue repair. Therefore, restoring redox balance instead of eliminating ROS has emerged as a rational therapeutic strategy. Microneedle (MN) platforms, particularly hydrogel-forming MNs, offer a uniquedelivery approach for this purpose by combining minimally invasive breach of the wound barrier with tunable swelling, high loading capacity, and controlled, localized release of redox-active agents into the wound bed and interstitial fluid. This review examines redox-active MN platforms for ROS modulation in chronic wound management, surveying ROS biology and wound healing physiology, the principal MN geometries and fabrication routes, and three major therapeutic categories: ROS-scavenging systems, ROS-generating systems and material and mechanistic design strategies beyond functional classification. We further discuss current challenges and future directions for translating these platforms toward clinical application. By integrating redox chemistry with MN engineering, hydrogel MN systems provide a versatile route to reestablish redox homeostasis and accelerate healing in chronic wounds. However, redox-active microneedle systems have not yet undergone clinical evaluation. Most efficacy data are derived from experimental animal wound models that do not accurately replicate the complexity of chronic wounds in humans, indicating that clinical translation remains at an early stage.