Sarsasapogenin, a principal active component absorbed into blood of total saponins of Anemarrhena, attenuates proliferation and invasion in rheumatoid arthritis fibroblast-like synoviocytes through downregulating PKM2 inhibited pathological glycolysis

Global Profiling of Lactylation Proteomics and Specific Lactylated Site Validation in Rheumatoid Arthritis Patients

Protein lactylation is a novel post-translational modification that has rarely been investigated in rheumatoid arthritis (RA). This study aimed to explore lactylation proteomics in RA patients and validate sorted candidate lactylation sites. Synovial tissues from ten RA and six osteoarthritis (OA) patients were subjected to lactylation proteomics via affinity enrichment and LC-MS/MS. Four candidate lactylated modification sites were validated by immunoprecipitation. Totally, 566 sites and 250 proteins with lactylated modifications in RA patients and 548 sites and 220 proteins with lactylated modifications in OA patients were identified. By comparison, 24 upregulated but 2 downregulated lactylated modification sites and 18 upregulated but 1 downregulated lactylated modification protein were discovered in RA patients versus OA patients. The dysregulated lactylated proteins were mainly enriched in biological processes such as positive regulation of plasma membrane repair by GO analysis; pathways such as neutrophil extracellular trap formation by KEGG analysis; and two metabolism-related items by COG/KOG analysis. Immunoprecipitation confirmed that FTH1-K69la (P = 0007) and PKM2-K166la (P = 0.003), but not ANXA2-K115la (P = 0.127) or ANXA5-K76la (P = 0.361), were more abundant in RA patients versus OA patients. Moreover, FTH1-K69la was positively correlated with erythrocyte sedimentation rate (ESR) in RA patients (P = 0.037). Conclusively, this study describes a general landscape of lactylation proteomics in the RA.

Allium Macrostemon Bge. Attenuates the Cognitive Decline of Aging Mice by Enhancing BDNF/TrkB Pathway

Allium macrostemon Bge. (AM) is a widely utilized culinary spice recognized for its numerous health-promoting properties. Aging-related cognitive impairment (ARCI) represents a significant global health concern during the aging process. However, the potential of AM to attenuate ARCI has not been investigated. This work aims to reveal the effects and potential mechanisms of the water extraction of AM (WEAM) in alleviating ARCI, with a particular emphasis on the BDNF/TrkB signaling pathway. The findings showed a significant enhancement in memory function and a reduction in hippocampal neuronal damage in aging mice following treatment with WEAM, manifested by an increased spontaneous alternation rate in the Y-maze, prolonged step-through latency, and decreased number of errors in the PAT test, a shortened escape latency and increased platform swimming time and platform crossing times in the MWM test. Additionally, WEAM reduced oxidative stress, elevated the expression of proteins related to synaptic plasticity (SYN and PSD95), and activated the BDNF/TrkB signaling pathway in D-galactose-induced aging mice. To elucidate the mechanism by which WEAM alleviates ARCI, both a TrkB activator (7,8-DHF) and an inhibitor (ANA-12) were employed. The results demonstrated that the effects of WEAM on synaptic plasticity were potentiated by 7,8-DHF and diminished by ANA-12. Finally, 11 chemical compositions of WEAM were analyzed and quantified using HPLC-MS/MS, including macrostemonoside, sarsasapogenin, diosgenin, timosaponin AIII, N-p-trans-coumaroyltyramine, guanosine, adenosine, phenylalanine, adenine, arginine, and valine. These results suggest that AM may serve as a promising culinary spice for mitigating ARCI by promoting the BDNF/TrkB signaling pathway, thereby enhancing synaptic plasticity.

Exploring the benefits and prescribing informations of combining East Asian herbal medicine with conventional medicine in the treatment of rheumatoid arthritis: A systematic review and multifaceted analysis of 415 randomized controlled trials

BACKGROUND

Notwithstanding progress in conventional medicine (CM), the management of rheumatoid arthritis (RA) continues to be problematic due to factors such as limited patient response to treatment and restricted medication access. This study aimed to evaluate the extent to which East Asian herbal medicine with CM combination therapy (EACM) provides additional benefits in effectiveness and safety.

METHODS

We conducted a comprehensive search across 11 databases in English, Chinese, Korean, and Japanese for randomized controlled trials. The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using the American College of Rheumatology (ACR) 20/50/70 Response Criteria and the incidence of adverse events (AEI) as primary outcomes. This meta-analysis was performed using a random-effects model. The quality of each study was assessed according to the RoB 2. Of the 1036 full-text articles screened, 415 were included in the review.

RESULTS

This review included data from 37,839 participants. EACM was associated with higher ACR responses: ACR 20 (RR: 1.2332; 95 % CI: 1.1852-1.2831, p < 0.0001), ACR 50 (RR: 1.3782; 95 % CI: 1.2936-1.4684, p < 0.0001), and ACR 70 (RR: 1.7084; 95 % CI: 1.5555-1.8762, p < 0.0001), as well as a favorable AEI (OR: 0.3977; 95 % CI: 0.3476-0.4551, p < 0.0001), indicating both better efficacy and safety compared to CM alone. These patterns were consistent across eight secondary outcomes measuring pain, inflammation, and disease activity in RA. Subgroup analyses showed that EACM's effects were independent of the control CM type. Through a comprehensive analysis of a polyherbal prescription dataset, we identified 18 key herbs and 16 significant combination rules, further supported by relevant preclinical evidence. These herbs and synergistic herbal combinations were anticipated to be the most pharmacologically influential in contributing to the meta-analysis outcomes, as substantiated by analytical metrics including network topology and intricate association pattern evaluations.

CONCLUSIONS

The findings suggest that EACM may serve as a valuable complementary strategy for RA patients insufficiently managed by CM alone. In particular, given that the ACR index integrates multiple aspects of RA patients, the results are expected to provide valuable complementary decision support for the management of RA patients who do not respond well to CM therapy, both for medical and economic reasons. Additionally, the key herbs derived through the multifaceted analysis, which actively reflect clinicians' implicit preferences for prescribing EACMs, may serve as important hypotheses for further research and clinical application. However, additional qualitative and quantitative improvements in research are needed for more definitive conclusions. Further analysis of the herbal prescriptions presented in this study will provide valuable direction for future research.

The Role of Pyruvate Kinase M2 Posttranslational Modification in the Occurrence and Development of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the deadly malignant tumors that directly leads to the death of nearly one million people worldwide every year, causing a serious burden on society. In the presence of sufficient oxygen, HCC cells rapidly generate energy through aerobic glycolysis, which promotes tumor cell proliferation, immune evasion, metastasis, angiogenesis, and drug resistance. Pyruvate kinase M2 (PKM2) is a key rate-limiting enzyme in glycolysis. In recent years, studies have found that PKM2 not only exerts pyruvate kinase activity in the process of glucose metabolism, but also exerts protein kinase activity in non-metabolic pathways to affect tumor cell processes, and its activity is flexibly regulated by various posttranslational modifications such as acetylation, phosphorylation, lactylation, ubiquitination, SUMOylation, and so forth. This review summarizes the role of posttranslational modifications of PKM2-related sites in the development of HCC.

Quality Evaluation of Polygonatum cyrtonema Hua Based on UPLC-Q-Exactive Orbitrap MS and Electronic Sensory Techniques with Different Numbers of Steaming Cycles

In this study, electronic sensory techniques were employed to comprehensively evaluate the organoleptic quality, chemical composition and content change rules for Polygonatum cyrtonema Hua (PCH) during the steaming process. The results were subjected to hierarchical cluster analysis (HCA), principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). These analyses revealed, from a sensory product perspective, overall differences in colour, odour and taste among the samples of PCH with different numbers of steaming cycles. Using the UPLC-Q-Exactive Orbitrap MS technique, 64 chemical components, including polysaccharides, organic acids, saponins and amino acids were detected in PCH before and after steaming. The sensory traits were then correlated with the chemical composition. From the perspectives of sensory traits, chemical composition, and multi-component index content, it was preliminarily deduced that carrying out five cycles of steaming and sun-drying was optimal, providing evidence for the quality evaluation of PCH during the steaming process.

Effects of Saponins on Lipid Metabolism: The Gut-Liver Axis Plays a Key Role

Unhealthy lifestyles (high-fat diet, smoking, alcohol consumption, too little exercise, etc.) in the current society are prone to cause lipid metabolism disorders affecting the health of the organism and inducing the occurrence of diseases. Saponins, as biologically active substances present in plants, have lipid-lowering, inflammation-reducing, and anti-atherosclerotic effects. Saponins are thought to be involved in the regulation of lipid metabolism in the body; it suppresses the appetite and, thus, reduces energy intake by modulating pro-opiomelanocortin/Cocaine amphetamine regulated transcript (POMC/CART) neurons and neuropeptide Y/agouti-related peptide (NPY/AGRP) neurons in the hypothalamus, the appetite control center. Saponins directly activate the AMP-activated protein kinase (AMPK) signaling pathway and related transcriptional regulators such as peroxisome-proliferator-activated-receptors (PPAR), CCAAT/enhancer-binding proteins (C/EBP), and sterol-regulatory element binding proteins (SREBP) increase fatty acid oxidation and inhibit lipid synthesis. It also modulates gut-liver interactions to improve lipid metabolism by regulating gut microbes and their metabolites and derivatives-short-chain fatty acids (SCFAs), bile acids (BAs), trimethylamine (TMA), lipopolysaccharide (LPS), et al. This paper reviews the positive effects of different saponins on lipid metabolism disorders, suggesting that the gut-liver axis plays a crucial role in improving lipid metabolism processes and may be used as a therapeutic target to provide new strategies for treating lipid metabolism disorders.

The role of PKM2 in cancer progression and its structural and biological basis

Pyruvate kinase M2 (PKM2), a subtype of pyruvate kinase (PK), has been shown to play an important role in the development of cancer. It regulates the last step of glycolytic pathway. PKM2 has both pyruvate kinase and protein kinase activity, and the conversion of these two functions of PKM2 depends on the mutual change of dimer and tetramer. The dimerization of PKM2 can promote the proliferation and growth of tumor cells, so inhibiting the dimerization of PKM2 is essential to curing cancer. The aggregation of PKM2 is regulated by both endogenous and exogenous cofactors as well as post-translational modification (PTM). Although there are many studies on the different aggregation of PKM2 in the process of tumor development, there are few summaries in recent years. In this review, we first introduce the role of PKM2 in various biological processes of tumor growth. Then, we summarize the aggregation regulation mechanism of PKM2 by various endogenous cofactors such as Fructose-1, 6-diphosphate (FBP), various amino acids, and post-translational modification (PTMs). Finally, the related inhibitors and agonists of PKM2 are summarized to provide reference for regulating PKM2 aggregation in the treatment of cancer in the future.

Identification of PKM2 as a pyroptosis-related key gene aggravates senile osteoporosis via the NLRP3/Caspase-1/GSDMD signaling pathway

BACKGROUNDS

Senile osteoporosis-alternatively labeled as skeletal aging-encompasses age-induced bone deterioration and loss of bone microarchitecture. Recent studies have indicated a potential association between senile osteoporosis and chronic systemic inflammation, and pyroptosis in bone marrow-derived mesenchymal stem cells is speculated to contribute to bone loss and osteoporosis. Therefore, targeting pyroptosis in stem cells may be a potential therapeutic strategy for treating osteoporosis.

METHODS

Initially, we conducted bioinformatics analysis to screen the GEO databases to identify the key gene associated with pyroptosis in senile osteoporosis. Next, we analyzed the relationship between altered proteins and clinical data. In vitro experiments were then performed to explore whether the downregulation of PKM2 expression could inhibit pyroptosis. Additionally, an aging-related mouse model of osteoporosis was established to validate the efficacy of a PKM2 inhibitor in alleviating osteoporosis progression.

RESULTS

We identified PKM2 as a key gene implicated in pyroptosis in senile osteoporosis patients through bioinformatics analysis. Further analyses of bone marrow and stem cells demonstrated significant PKM2 overexpression in senile osteoporosis patients. Silencing PKM2 expression inhibited pyroptosis in senile stem cells, of which the osteogenesis potential and angiogenic function were also primarily promoted. Moreover, the results in vivo demonstrated that administering PKM2 inhibitors suppressed pyroptosis in senile osteoporosis mice and mitigated senile osteoporosis progression.

CONCLUSION

Our study uncovered PKM2, a key pyroptosis marker of bone marrow mesenchymal stem cells in senile osteoporosis. Shikonin, a PKM2 inhibitor, was then identified as a potential drug candidate for the treatment of osteoporosis.

Targeting glycolytic pathway in fibroblast-like synoviocytes for rheumatoid arthritis therapy: challenges and opportunities

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by hyperplastic synovium, pannus formation, immune cell infiltration, and potential articular cartilage damage. Notably, fibroblast-like synoviocytes (FLS), especially rheumatoid arthritis fibroblast-like synoviocytes (RAFLS), exhibit specific overexpression of glycolytic enzymes, resulting in heightened glycolysis. This elevated glycolysis serves to generate ATP and plays a pivotal role in immune regulation, angiogenesis, and adaptation to hypoxia. Key glycolytic enzymes, such as hexokinase 2 (HK2), phosphofructose-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), and pyruvate kinase M2 (PKM2), significantly contribute to the pathogenic behavior of RAFLS. This increased glycolysis activity is regulated by various signaling pathways.

MATERIALS AND METHODS

A comprehensive literature search was conducted to retrieve relevant studies published from January 1, 2010, to the present, focusing on RAFLS glycolysis, RA pathogenesis, glycolytic regulation pathways, and small-molecule drugs targeting glycolysis.

CONCLUSION

This review provides a thorough exploration of the pathological and physiological characteristics of three crucial glycolytic enzymes in RA. It delves into their putative regulatory mechanisms, shedding light on their significance in RAFLS. Furthermore, the review offers an up-to-date overview of emerging small-molecule candidate drugs designed to target these glycolytic enzymes and the upstream signaling pathways that regulate them. By enhancing our understanding of the pathogenic mechanisms of RA and highlighting the pivotal role of glycolytic enzymes, this study contributes to the development of innovative anti-rheumatic therapies.

M6A methylation modification in autoimmune diseases, a promising treatment strategy based on epigenetics

BACKGROUND

N6-methyladenosine (m6A) methylation modification is involved in the regulation of various biological processes, including inflammation, antitumor, and antiviral immunity. However, the role of m6A modification in the pathogenesis of autoimmune diseases has been rarely reported.

METHODS

Based on a description of m6A modification and the corresponding research methods, this review systematically summarizes current insights into the mechanism of m6A methylation modification in autoimmune diseases, especially its contribution to rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).

RESULTS

By regulating different biological processes, m6A methylation is involved in the pathogenesis of autoimmune diseases and provides a promising biomarker for the diagnosis and treatment of such diseases. Notably, m6A methylation modification is involved in regulating a variety of immune cells and mitochondrial energy metabolism. In addition, m6A methylation modification plays a role in the pathological processes of RA, and m6A methylation-related genes can be used as potential targets in RA therapy.

CONCLUSIONS

M6A methylation modification plays an important role in autoimmune pathological processes such as RA and SLE and represents a promising new target for clinical diagnosis and treatment, providing new ideas for the treatment of autoimmune diseases by targeting m6A modification-related pathways.