Aspirin reverses inflammatory suppression of chondrogenesis by stabilizing YAP

Reconstruction of quality marker system for Ginkgo Folium tablet using UHPLC-Q-Orbitrap MS, quantum chemical calculation, network pharmacology, and molecular simulation

INTRODUCTION

Ginkgo Folium tablet (GFT) is a patented traditional Chinese medicine prepared from Ginkgo biloba leaves extract (GBE). However, the current quality indicators for GFT or GBE as designated by the Chinese Pharmacopoeia are insufficient in preventing counterfeit events.

OBJECTIVE

This study aimed to putatively identify compounds in GFT and to further develop a quality marker (Q-marker) system for GFT.

METHODS

A novel strategy utilizing database-aided ultrahigh-performance liquid chromatography-quadrupole-orbitrap mass spectrometry was employed to analyze the lyophilized aqueous powder of GFT. Subsequently, the identified compounds underwent quantum chemical calculations, network pharmacology, and molecular simulations through in silico approaches to evaluate the Q-marker principles of traceability, specificity, and efficiency-relevance.

RESULTS

The results revealed the putative identification of a total of 66 compounds, including 36 flavonoids, 7 phenolic acids and derivatives, 5 terpene lactones, 4 fatty acids and derivatives, 3 alkaloids, 1 amino acid, and 10 other compounds. Particularly, 16 compounds were unexpectedly observed, and seven compounds met the Q-marker principles.

CONCLUSION

This study recommends the seven compounds, namely, (-)-gallocatechin, matrine, (-)-epicatechin, ginkgolide C, ginkgolide A, ginkgolide B, and curdione, as the anti-counterfeiting pharmacopoeia Q-markers for GFT. The reconstruction of the Q-marker system for GFT not only enhances the understanding of the compounds in GFT and other GBE-based preparations but also provides valuable recommendations for the Pharmacopoeia Commission.

Aspirin attenuates the detrimental effects of TNF-α on BMMSC stemness by modulating the YAP-SMAD7 axis

BACKGROUND

Bone marrow mesenchymal stem cells (BMMSCs) are commonly used for cell transplantation to treat refractory diseases. However, the presence of inflammatory factors, such as tumour necrosis factor-alpha (TNF-α), at the transplantation site severely compromises the stemness of BMMSCs, thereby reducing the therapeutic effect of cell transplantation. Aspirin (AS) is a drug that has been in use for over a century and has a wide range of effects, including the regulation of cell proliferation, multidirectional differentiation, and immunomodulatory properties of stem cells. However, it is still unclear whether AS can delay the damaging effects of TNF-α on BMMSC stemness.

METHODS

This study investigated the effects of AS and TNF-α on BMMSC stemness and the molecular mechanisms using colony formation assay, western blot, qRT-PCR, and overexpression or knockdown of YAP and SMAD7.

RESULTS

The results demonstrated that TNF-α inhibited cell proliferation, the expression of stemness, osteogenic and chondrogenic differentiation markers of BMMSCs. Treatment with AS was shown to mitigate the TNF-α-induced damage to BMMSC stemness. Mechanistic studies revealed that AS may reverse the damage caused by TNF-α on BMMSC stemness by upregulating YAP and inhibiting the expression of SMAD7.

CONCLUSION

AS can attenuate the damaging effects of TNF-α on BMMSC stemness by regulating the YAP-SMAD7 axis. These findings are expected to promote the application of AS to improve the efficacy of stem cell therapy.

The role of YAP/TAZ on joint and arthritis

Osteoarthritis (OA) and rheumatoid arthritis (RA) are two common forms of arthritis with undefined etiology and pathogenesis. Yes-associated protein (YAP) and its homolog transcriptional coactivator with PDZ-binding motif (TAZ), which act as sensors for cellular mechanical and inflammatory cues, have been identified as crucial players in the regulation of joint homeostasis. Current studies also reveal a significant association between YAP/TAZ and the pathogenesis of OA and RA. The objective of this review is to elucidate the impact of YAP/TAZ on different joint tissues and to provide inspiration for further studying the potential therapeutic implications of YAP/TAZ on arthritis. Databases, such as PubMed, Cochran Library, and Embase, were searched for all available studies during the past two decades, with keywords "YAP," "TAZ," "OA," and "RA."

The Hippo-YAP Signaling Pathway in Osteoarthritis and Rheumatoid Arthritis

Arthritis is the most prevalent joint disease and is characterized by articular cartilage degradation, synovial inflammation, and changes in periarticular and subchondral bone. Recent studies have reported that Yes-associated protein (YAP) and the transcriptional coactivator with PDZ-binding motif (TAZ) have significant effects on the proliferation, migration, and survival of chondrocytes and fibroblast-like synovial cells (FLSs). YAP/TAZ signaling pathway, as well as the related Hippo-YAP signaling pathway, are responsible for the condition of cells and articular cartilage in joints. They are tightly regulated to maintain metabolism in chondrocytes and FLSs because abnormal expression may result in cartilage damage. However, the roles and mechanisms of the Hippo-YAP pathway in arthritis remain largely unknown. This review summarizes the roles and key functions of YAP/TAZ and the Hippo-YAP signaling pathway in FLSs and chondrocytes for the induction of proliferation, migration, survival, and differentiation in rheumatoid arthritis (RA) and osteoarthritis (OA) research. We also discuss the therapeutic strategies involving YAP/TAZ and the related Hippo-YAP signaling pathway involved in OA.

Mechanical loading and autophagy: A study on the BoNT-A injection-induced condylar cartilage degeneration

Botulinum toxin A (BoNT-A) has emerged as a treatment option for temporomandibular disorder (TMD). By injecting BoNT-A into the masseter muscle, it is possible to reduce mechanical loading on the temporomandibular joint (TMJ). However, numerous prior studies have indicated excessive reduction in mechanical loading can have detrimental effects on TMJ cartilage. This study proposes that autophagy, a process influenced by mechanical loading, could play a role in BoNT-A-induced mandibular condyle cartilage degeneration. To explore this hypothesis, we employed both BoNT-A injection and an excessive biting model to induce variations in mechanical loading on the condyle cartilage of C57BL/6 mice, thereby simulating an increase and decrease in mechanical loading, respectively. Results showed a significant reduction in cartilage thickness and downregulation of Runt-related transcription factor 2 (Runx2) expression in chondrocytes following BoNT-A injection. In vitro experiments demonstrated that the reduction of Runx2 expression in chondrocytes is associated with autophagy, possibly dependent on decreased YAP expression induced by low mechanical loading. This study reveals the potential involvement of the YAP/LC3/Runx2 signaling pathway in BoNT-A mediated mandibular condylar cartilage degeneration.