Spatiotemporal and Transcriptional Characterization on Tanshinone Initial Synthesis in Salvia miltiorrhiza Roots

Proteins and DNA Sequences Interacting with Tanshinones and Tanshinone Derivatives

Tanshinones, biologically active diterpene compounds derived from Salvia miltiorrhiza, interact with specific proteins and DNA sequences, influencing signaling pathways in animals and humans. This study highlights tanshinone-protein interactions observed at concentrations achievable in vivo, ensuring greater physiological relevance compared to in vitro studies that often employ supraphysiological ligand levels. Experimental data suggest that while tanshinones interact with multiple proteomic targets, only a few enzymes are significantly affected at biologically relevant concentrations. This apparent paradox may be resolved by tanshinones' ability to bind DNA and influence enzymes involved in gene expression or mRNA stability, such as RNA polymerase II and human antigen R protein. These interactions trigger secondary, widespread changes in gene expression, leading to complex proteomic alterations. Although the current understanding of tanshinone-protein interactions remains incomplete, this study provides a foundation for deciphering the molecular mechanisms underlying the therapeutic effects of S. miltiorrhiza diterpenes. Additionally, numerous tanshinone derivatives have been developed to enhance pharmacokinetic properties and biological activity. However, their safety profiles remain poorly characterized, limiting comprehensive insights into their medicinal potential. Further investigation is essential to fully elucidate the therapeutic and toxicological properties of both native and modified tanshinones.

Metabolic and transcriptional analysis of tuber expansion in Curcuma kwangsiensis

The tubers of Curcuma kwangsiensis are regarded as an important medicinal material in China. In C. kwangsiensis cultivation, tuber expansion is key to yield and quality, but the regulatory mechanisms are not well understood. In this study, metabolomic and transcriptomic analyses were conducted to elucidate the mechanism underlying tuber expansion development. The results showed that auxin (IAA), jasmonic acid (JA), gibberellin (GA3), ethylene (ETH), and brassinolide (BR) levels increased during tuber expansion development. Metabolomic analysis showed that 197 differentially accumulated metabolites (DAMs) accumulated during tuber expansion development and these also play important roles in the accumulation of carbohydrates and secondary metabolites. 6962 differentially expressed genes (DEGs) were enriched in plant hormone signal transduction, starch and sucrose metabolism, linoleic acid metabolism, MAPK signaling pathway as well as sesquiterpenoid and triterpenoid biosynthesis. Comprehensive analysis revealed that DEGs and DAMs of plant hormone signal transduction, ABC transporters and biosynthesis of phenylpropanoids and terpenoids are critical pathways in regulating tuber expansion. In addition, some transcription factors (ARF, C2H2, C3H, NAC, bHLH, GRAS and WRKY) as well as hub genes (HDS, HMGR, ARF7, PP2CA, PAL and CCOMT) are also involved in this process. This study lays a theoretical basis for the molecular mechanism of tuber expansion in C. kwangsiensis.

Metabolomics analysis reveals the effects of Salvia Miltiorrhiza Bunge extract on ameliorating acute myocardial ischemia in rats induced by isoproterenol

Salvia miltiorrhiza Bunge (SM) is a widespread herbal therapy for myocardial ischemia (MI). Nevertheless, the therapeutic signaling networks of SM extract on MI is yet unknown. Emerging evidences suggested that alterations in cardiac metabolite influences host metabolism and accelerates MI progression. Herein, we employed an isoproterenol (ISO)-induced acute myocardial ischemia (AMI) rat model to confirm the pharmacological effects of SM extract (0.8, 0.9, 1.8 g/kg/day) via assessment of the histopathological alterations that occur within the heart tissue and associated cytokines; we also examined the underlying SM extract-mediated signaling networks using untargeted metabolomics. The results indicated that 25 compounds with a relative content higher than 1 % in SM aqueous extract were identified using LC-MS/MS analysis, which included salvianolic acid B, lithospermic acid, salvianolic acid A, and caffeic acid as main components. An in vivo experiment showed that pretreatment with SM extract attenuated ISO-induced myocardial injury, shown as decreased myocardial ischemic size, transformed electrocardiographic, histopathological, and serum biochemical aberrations, reduced levels of proinflammatory cytokines, inhibited oxidative stress (OS), and reversed the trepidations of the cardiac tissue metabolic profiles. Metabolomics analysis shows that the levels of 24 differential metabolites (DMs) approached the same value as controls after SM extract therapy, which were primarily involved in histidine; alanine, aspartate, and glutamate; glycerophospholipid; and glycine, serine, and threonine metabolisms through metabolic pathway analysis. Correlation analysis demonstrated that the levels of modulatory effects of SM extract on the inflammation and OS were related to alterations in endogenous metabolites. Overall, SM extract demonstrated significant cardioprotective effects in an ISO-induced AMI rat model, alleviating myocardial injury, inflammation and oxidative stress, with metabolomics analysis indicating potential therapeutic pathways for myocardial ischemia.

Endophytic fungus Penicillium steckii DF33 promoted tanshinones biosynthesis in Salvia miltiorrhiza by regulating the expression of CYP450 genes

Salvia miltiorrhiza, a prominent traditional Chinese medicinal resource, has been extensively employed in the management of cardiovascular and cerebrovascular ailments. Ensuring the consistency of S. miltiorrhiza raw materials revolves around the imperative task of maintaining stable tanshinones content and composition. An effective approach in this regard involves the utilization of endophytic fungi as inducers. Within this context, our study spotlights an endophytic fungus, Penicillium steckii DF33, isolated from the roots of S. miltiorrhiza. Remarkably, this fungus has demonstrated a significant capacity to boost the biosynthesis and accumulation of tanshinones. The primary objective of this investigation is to elucidate the underlying regulatory mechanism by which DF33 enhances and regulates the biosynthesis and accumulation of tanshinones. This is achieved through its influence on the differential expression of crucial CYP450 genes within the S. miltiorrhiza hairy roots system. The results revealed that the DF33 elicitor not only promotes the growth of hairy roots but also enhances the accumulation of tanshinones. Notably, the content of cryptotanshinone was reached 1.6452 ± 0.0925 mg g-1, a fourfold increase compared to the control group. Our qRT-PCR results further demonstrate that the DF33 elicitor significantly up-regulates the expression of most key enzyme genes (GGPPS, CPS1, KSL1, CYP76AH1, CYP76AH3, CYP76AK1, CYP71D411) involved in the tanshinone biosynthesis pathway. This effect is particularly pronounced in certain critical CYP450 genes and Tanshinone ⅡA synthase (SmTⅡAS), with their expression levels peaking at 7 days or 14 days, respectively. In summary, endophytic P. steckii DF33 primarily enhances tanshinone biosynthesis by elevating the expression levels of pivotal enzyme genes associated with the modification and transformation stages within the tanshinone biosynthesis pathway. These findings underscore the potential of employing plant probiotics, specifically endophytic and root-associated microbes, to facilitate the biosynthesis and transformation of vital constituents in medicinal plants, and this approach holds promise for enhancing the quality of traditional Chinese medicinal materials.

Microbial fortification of pharmacological metabolites in medicinal plants

Medicinal plants are rich in secondary metabolites with beneficial pharmacological effects. The production of plant secondary metabolites is subjected to the influences by environmental factors including the plant-associated microbiome, which is crucial to the host's fitness and survival. As a result, research interests are increasing in exploiting microbial capacities for enhancing plant production of pharmacological metabolites. A growing body of recent research provides accumulating evidence in support of developing microbe-based tools for achieving this objective. This mini review presents brief summaries of recent studies on medicinal plants that demonstrate microbe-augmented production of pharmacological terpenoids, polyphenols, and alkaloids, followed by discussions on some key questions beyond the promising observations. Explicit molecular insights into the underlying mechanisms will enhance microbial applications for metabolic fortification in medicinal plants.