Effects and Mechanism of Berberine on the Dexamethasone-Induced Injury of Human Tendon Cells

Berberine alleviates tendinopathy by suppressing the cGAS-STING pathway and Relieving ferroptosis

Berberine, a key bioactive component of Coptis rhizome, has been extensively studied for its therapeutic effects on various diseases. This research aimed to investigate the potential benefits of berberine in treating tendinopathy and to elucidate the underlying mechanisms through animal and laboratory studies. Our findings indicated that berberine effectively treated type I collagenase-induced tendinopathy in rats, confirmed by cellular-level validation. At the molecular level, berberine reduced the activation of the cGAS-STING signaling pathway and decreased the accumulation of malondialdehyde (MDA) and reactive oxygen species (ROS) in both animal models and cell cultures. Additionally, berberine upregulated the expression of glutathione (GSH) and glutathione peroxidase 4 (GPX4) in tissues. These results suggested that berberine alleviated ferroptosis via the cGAS-STING pathway, thus exerting therapeutic effects on tendinopathy. To validate these findings further, we administered the ferroptosis inducer Imidazole Ketone Erastin (IKE) to evaluate the effects of berberine. IKE significantly diminished the therapeutic effects of berberine on tendinopathy, as indicated by the previously mentioned markers. Thus, berberine mitigated ferroptosis by inhibiting the cGAS-STING pathway, highlighting its potential in managing tendinopathy.

Development and evaluation of a strontium-doped berberine quantum dot-loaded nanofibrous dressing for accelerated wound healing in animal models

This research focused on fabricating a new type of wound dressing made from nanofibers infused with strontium-doped berberine carbon quantum dots (Str-Ber-CQD) to speed up healing and improve the quality of healed tissue. We applied a hydrothermal method using berberine as the carbon source to synthesize Str-Ber-CQD and then blended it into nanofibers made from scleroglucan/polyvinyl alcohol at different concentrations. The results showed that the CQDs have spherical morphology with a size of 3.6 ± 0.9 nm, an average hydrodynamic diameter of 53.2 ± 2.1 nm, and a PDI of 0.350. The XPS and EDX analysis showed that CQDs were composed of C, O, N, and Sr. The fabricated nanofibers have a uniform morphology with promising mechanical strength, swelling capacity, biodegradation, water vapor transmittance rate, and microbial barrier potential. The in vitro biological evaluations confirmed potent antioxidant and antibacterial activities and excellent hemocompatibility/cytocompatibility. The animal studies showed that the optimum structure (nanofibers/ Str-Ber-CQD 5 %) showed impressive results in animal tests involving full-thickness skin wounds. In summary, this study demonstrates that nanofibers/Str-CQD exhibited promising physical, chemical, and biological properties and can be considered a multifunctional wound dressing.

Roles of Oxidative Stress in Acute Tendon Injury and Degenerative Tendinopathy-A Target for Intervention

Both acute and chronic tendon injuries are disabling sports medicine problems with no effective treatment at present. Sustained oxidative stress has been suggested as the major factor contributing to fibrosis and adhesion after acute tendon injury as well as pathological changes of degenerative tendinopathy. Numerous in vitro and in vivo studies have shown that the inhibition of oxidative stress can promote the tenogenic differentiation of tendon stem/progenitor cells, reduce tissue fibrosis and augment tendon repair. This review aims to systematically review the literature and summarize the clinical and pre-clinical evidence about the potential relationship of oxidative stress and tendon disorders. The literature in PubMed was searched using appropriate keywords. A total of 81 original pre-clinical and clinical articles directly related to the effects of oxidative stress and the activators or inhibitors of oxidative stress on the tendon were reviewed and included in this review article. The potential sources and mechanisms of oxidative stress in these debilitating tendon disorders is summarized. The anti-oxidative therapies that have been examined in the clinical and pre-clinical settings to reduce tendon fibrosis and adhesion or promote healing in tendinopathy are reviewed. The future research direction is also discussed.