Identification of Glutathione Peroxidase (GPX) Gene Family in Rhodiola crenulata and Gene Expression Analysis under Stress Conditions.

Glutathione peroxidases (GPXs) are important enzymes in the glutathione-ascorbate cycle for catalyzing the reduction of H2O2 or organic hydroperoxides to water. GPXs play an essential role in plant growth and development by participating in photosynthesis, respiration, and stress tolerance. Rhodiola crenulata is a popular traditional Chinese medicinal plant which displays an extreme energy of tolerance to harsh alpine climate. The GPXs gene family might provide R. crenulata for extensively tolerance to environment stimulus. In this study, five GPX genes were isolated from R. crenulata. The protein amino acid sequences were analyzed by bioinformation softwares with the results that RcGPXs gene sequences contained three conserve cysteine residues, and the subcellular location predication were in the chloroplast, endoplasmic reticulum, or cytoplasm. Five RcGPXs members presented spatial and temporal specific expression with higher levels in young and green organs. And the expression patterns of RcGPXs in response to stresses or plant hormones were investigated by quantitative real-time PCR. In addition, the putative interaction proteins of RcGPXs were obtained by yeast two-hybrid with the results that RcGPXs could physically interact with specific proteins of multiple pathways like transcription factor, calmodulin, thioredoxin, and abscisic acid signal pathway. These results showed the regulation mechanism of RcGPXs were complicated and they were necessary for R. crenulata to adapt to the treacherous weather in highland.

BREAKING NEW GROUND: STANDARDIZING RAT MODELS FOR CRUSH SYNDROME INVESTIGATIONS.

ABSTRACT: Crush syndrome (CS), alternatively termed traumatic rhabdomyolysis, is a paramount posttraumatic complication. Given the infeasibility of conducting direct simulation research in humans, the role of animal models is pivotal. Regrettably, the dearth of standardized animal models persists. The objective of this study was to construct a repeatable standardized rat CS models and, based on this, simulate specific clinical scenarios. Methods: Using a self-developed multichannel intelligent small-animal crush injury platform, we applied a force of 5 kg to the hind limbs of 8-week-old rats (280-300 g), subjecting them to a continuous 12 h compression to establish the CS model. Continuous monitoring was conducted for both the lower limbs and the overall body status. After decompression, biochemical samples were collected at 3, 6, 12, and 24 h. In addition, we created a CS model after resection of the left kidney (UNx-CS), which was conceptualized to simulate a more challenging clinical scenario to investigate the physiological and pathological responses rats with renal insufficiency combined with crush injury. The results were compared with those of the normal CS model group. Results : Our experiments confirm the stability of the crush injury platform. We defined the standardized conditions for modeling and successfully established rats CS model in bulk. After 12 h of compression, only 40% of the rats in the CS group survived for 24 h. Systemically, there was clear evidence of insufficient perfusion, reflecting the progression of CS from localized to generalized. The injured limbs displayed swelling, localized perfusion deficits, and severe pathological alterations. Significant changes were observed in blood biochemical markers: aspartate transaminase, lactate dehydrogenase, K+, creatine kinase, creatinine, and blood urea nitrogen levels rose rapidly after decompression and were significantly higher than the sham group. The kidney demonstrated characteristic pathological changes consistent with established CS diagnostic criteria. Although the UNx-CS rat model did not exhibit significant biochemical differences and pathological scores when compared with the standard CS model, it did yield intriguing results with regard to kidney morphology. The UNx-CS group manifested a higher incidence of cortical and medullary protein casts compared with the NC-CS group. Conclusion: We developed and iteratively refined a novel digital platform, addressing the multiple uncontrollable variables that plagued prior models. This study validated the stability of the platform, defined the standardized conditions for modeling and successfully established the CS model with good repeatability in bulk. In addition, our innovative approach to model a clinically challenging scenario, the UNx-CS rat model. This offers an opportunity to delve deeper into understanding the combined effects of preexisting renal compromise and traumatic injury. In summary, the development of a standardized, reproducible CS model in rats represents a significant milestone in the study of Crush syndrome. This study is of paramount significance as it advances the standardization of the CS model, laying a solid foundation for subsequent studies in related domains, especially in CS-AKI.

Progress in injectable hydrogels for the treatment of incompressible bleeding: an update.

Uncontrollable haemorrhage from deep, noncompressible wounds remains a persistent and intractable challenge, accounting for a very high proportion of deaths in both war and disaster situations. Recently, injectable hydrogels have been increasingly studied as potential haemostatic materials, highlighting their enormous potential for the management of noncompressible haemorrhages. In this review, we summarize haemostatic mechanisms, commonly used clinical haemostatic methods, and the research progress on injectable haemostatic hydrogels. We emphasize the current status of injectable hydrogels as haemostatic materials, including their physical and chemical properties, design strategy, haemostatic mechanisms, and application in various types of wounds. We discuss the advantages and disadvantages of injectable hydrogels as haemostatic materials, as well as the opportunities and challenges involved. Finally, we propose cutting-edge research avenues to address these challenges and opportunities, including the combination of injectable hydrogels with advanced materials and innovative strategies to increase their biocompatibility and tune their degradation profile. Surface modifications for promoting cell adhesion and proliferation, as well as the delivery of growth factors or other biologics for optimal wound healing, are also suggested. We believe that this paper will inform researchers about the current status of the use of injectable haemostatic hydrogels for noncompressible haemorrhage and spark new ideas for those striving to propel this field forward.

An Antibacterial and Antiadhesion In Situ Forming Hydrogel with Sol-Spray System for Noncompressible Hemostasis.

Noncompressible hemorrhage is a major cause of posttrauma death and occupies the leading position among potentially preventable trauma-associated deaths. Recently, multiple studies have shown that strongly adhesive materials can serve as hemostatic materials for noncompressible hemorrhage. However, the risk of severe tissue adhesion limits the use of adhesive hydrogels as hemostatic materials. Here, we report a promising material system comprising an injectable sol and liquid spray as a potential solution. Injectable sol is mainly composed of gelatin (GEL) and sodium alginate (SA), which possess hemostasis and adhesive properties. The liquid spray component, a mixture of tannic acid (TA) and calcium chloride (CaCl2), rapidly forms an antibacterial, antiadhesive and smooth film structure upon contact with the sol. In vitro and in vivo experiments demonstrated the bioabsorbable, biocompatible, antibacterial, and antiadhesion properties of the in situ forming hydrogel with a sol-spray system. Importantly, the addition of tranexamic acid (TXA) enhanced hemostatic performance in noncompressible areas and in deep wound hemorrhage. Our study offers a new multifunctional hydrogel system to achieve noncompressible hemostasis.

3D bioprinting: opportunities for wound dressing development.

The skin is the body's first line of defence, and its physiology is complex. When injury occurs, the skin goes through a complex recovery process, and there is the risk of developing a chronic wound. Therefore, proper wound care is critical during the healing process. In response to clinical needs, wound dressings have been developed. There are several types of wound dressings available for wound healing, but there are still many issues to overcome. With its high controllability and resolution, three-dimensional (3D) printing technology is widely regarded as the technology of the next global industrial and manufacturing revolution, and it is a key driving force in the development of wound dressings. Here, we briefly introduce the wound healing mechanism, organize the history and the main technologies of 3D bioprinting, and discuss the application as well as the future direction of development of 3D bioprinting technology in the field of wound dressings.

Biomimetic tri-layered small-diameter vascular grafts with decellularized extracellular matrix promoting vascular regeneration and inhibiting thrombosis with the salidroside.

Small-diameter vascular grafts (SDVGs) are urgently required for clinical applications. Constructing vascular grafts mimicking the defining features of native arteries is a promising strategy. Here, we constructed a tri-layered vascular graft with a native artery decellularized extracellular matrix (dECM) mimicking the component of arteries. The porcine thoracic aorta was decellularized and milled into dECM powders from the differential layers. The intima and media dECM powders were blended with poly (L-lactide-co-caprolactone) (PLCL) as the inner and middle layers of electrospun vascular grafts, respectively. Pure PLCL was electrospun as a strengthening sheath for the outer layer. Salidroside was loaded into the inner layer of vascular grafts to inhibit thrombus formation. In vitro studies demonstrated that dECM provided a bioactive milieu for human umbilical vein endothelial cell (HUVEC) extension adhesion, proliferation, migration, and tube-forming. The in vivo studies showed that the addition of dECM could promote endothelialization, smooth muscle regeneration, and extracellular matrix deposition. The salidroside could inhibit thrombosis. Our study mimicked the component of the native artery and combined it with the advantages of synthetic polymer and dECM which provided a promising strategy for the design and construction of SDVGs.

Overexpression of the Glutathione Peroxidase 5 (RcGPX5) Gene From Rhodiola crenulata Increases Drought Tolerance in Salvia miltiorrhiza.

Excessive cellular accumulation of reactive oxygen species (ROS) due to environmental stresses can critically disrupt plant development and negatively affect productivity. Plant glutathione peroxidases (GPXs) play an important role in ROS scavenging by catalyzing the reduction of H2O2 and other organic hydroperoxides to protect plant cells from oxidative stress damage. RcGPX5, a member of the GPX gene family, was isolated from a traditional medicinal plant Rhodiola crenulata and constitutively expressed in Salvia miltiorrhiza under control of the CaMV 35S promoter. Transgenic plants showed increased tolerance to oxidative stress caused by application of H2O2 and drought, and had reduced production of malondialdehyde (MDA) compared with the wild type. Under drought stress, seedlings of the transgenic lines wilted later than the wild type and recovered growth 1 day after re-watering. In addition, the reduced glutathione (GSH) and total glutathione (T-GSH) contents were higher in the transgenic lines, with increased enzyme activities including glutathione reductase (GR), ascorbate peroxidase (APX), and GPX. These changes prevent H2O2 and O2 - accumulation in cells of the transgenic lines compared with wild type. Overexpression of RcGPX5 alters the relative expression levels of multiple endogenous genes in S. miltiorrhiza, including transcription factor genes and genes in the ROS and ABA pathways. In particular, RcGPX5 expression increases the mass of S. miltiorrhiza roots while reducing the concentration of the active ingredients. These results show that heterologous expression of RcGPX5 in S. miltiorrhiza can affect the regulation of multiple biochemical pathways to confer tolerance to drought stress, and RcGPX5 might act as a competitor with secondary metabolites in the S. miltiorrhiza response to environmental stimuli.