Analysis of the improvement effect of Astragalus extract on oxidative stress injury in viral myocarditis through STAT3/IL-6.

The objective of this study was to investigate the improvement effect of Astragalus (AS) extract on oxidative stress (OS) and inflammatory response of myocarditis (MYO) cells through the STAT3/IL-6 axis. For this purpose, The MYO model cells prepared by intervening cardiomyocyte HL-1 with Coxsackievirus B3 (CVB3) were divided into four groups: model group, as well as high- (H-), medium- (M-) and low-dose (L-) AS groups treated by 80, 40, and 20 µg/mL AS, respectively. Conventionally cultured cells were set as the normal group. Cell multiplication and apoptosis, as well as levels of Myocardial injury markers (cTnT, BNP and CK), inflammatory cytokines (ICs; TNF-α, IL-1ß and IL-6) and OS indices (SOD, GSH-Px and MDA), were measured. STAT3/IL-6 pathway expression was also observed. Results showed that the model group presented decreased cell multiplication than the normal group, but with increased myocardial injury, apoptosis rate, Caspase3 protein, ICs and OS reaction (P < 0.05); In the three AS-intervened groups, enhanced cell multiplication, while reduced myocardial injury, apoptosis rate, ICs and OS response were observed, especially in H-AS group (P < 0.05). Besides, STAT3 and IL-6 concentrations, statistically increased in the model group, were reduced by AS intervention (P < 0.05). Colivelin, a specific activator of STAT3, further aggravated the apoptosis, inflammatory reaction and OS response of MYO cells (P < 0.05), but its impacts on MYO cells could be reversed by AS. In conclusion, AS can ameliorate MYO, and its mechanism is related to the inhibition of cellular inflammatory response and OS response through the STAT3/IL-6 axis.

MEDAG expression in vitro and paeoniflorin alleviates bone loss by regulating the MEDAG/AMPK/PPARγ signaling pathway in vivo.

Objectives: Osteoporosis (OP) is characterized by reduced bone mass and impaired bone microstructure. Paeoniflorin (PF) is isolated from peony root with anti-inflammatory, immunomodulatory, and bone-protective effects. Up to now, the mechanism of anti-OP in PF has not been completely clarified. Methods: The expression of MEDAG in osteoclasts, osteoblasts and adipocytes was detected by RT-qPCR. The OVX mouse model was constructed, and oral administration of PF was performed for 15 weeks. Bone microstructure was detected by H&E staining and a micro-CT system, and expression of signaling proteins examined by Western blot and immunohistochemical staining. ELISA and biochemical kits were used to quantify serum metabolite levels. Key findings: MEDAG were upregulated in osteoclasts and adipocytes, and downregulated in osteoblasts. PF administration effectively alleviated OVX-induced bone loss, and histological changes in femur tissues. Moreover, PF significantly reduced serum TRAP, CTX-1, P1NP, BALP, and LDL-C levels and increased HDL-C. In addition, PF inhibited the expression of MEDAG, cathepsin K, NFATc1, PPARγ, and C/EBPα and increased p-AMPKα, OPG and Runx2. Conclusions: MEDAG is a potential target for bone diseases, and PF might attenuate OVX-induced osteoporosis via MEDAG/AMPK/PPARγ signaling pathway.

Constructing multifunctional Cu Single-Atom nanozyme for synergistic nanocatalytic Therapy-Mediated Multidrug-Resistant bacteria infected wound healing.

Developing an effective strategy to combat multi-drug-resistant (MDR) bacteria and promote wound healing without overuse of antibiotics remains an important and challenging goal. Herein, we established a synergistic reactive oxygen species (ROS) and reactive nitrogen species (RNS)-mediated nanocatalytic therapy, which was consisted of a multifunctional Cu single-atom nanozyme loaded with the l-arginine (l-Arg@Cu-SAzymes) and a low level of hydrogen peroxide (H2O2) as a trigger. l-Arg@Cu-SAzymes can possess excellent dual enzyme-like activities: catalase (CAT)-like activity that decompose H2O2 into O2, and subsequent oxidase (OXD)-like activity that convert O2 to cytotoxic superoxide anion radical (•O2-). Meanwhile, l-Arg@Cu-SAzymes can also be triggered by H2O2 to release nitric oxide (NO), which can continue to react with •O2- to generate more lethal peroxynitrite (ONOO-). Collectively, the synergistic ROS and RNS mediated by l-Arg@Cu-SAzymes endow the treatment system with an outstanding antibacterial ability against MDR bacteria and reduce the inflammation at the wound site. Furthermore, l-Arg@Cu-SAzymes-mediated NO and O2 release promote the cell proliferation, collagen synthesis, and the angiogenesis, as well as facilitate macrophage polarization to reparative M2 phenotype, thereby accelerating wound closure and tissue remodeling. Therefore, l-Arg@Cu-SAzymes-based synergistic nanocatalytic therapy can be regarded as a promising strategy for MDR bacterial infected wounds treatment, owing to their potent antibacterial efficacy and enhanced tissue remodeling effects.