Fraxin Ameliorates Ulcerative Colitis by Modulating Oxidative Stress, Inflammation and TLR4/NF-κB and MAPK Signaling Pathways.

Objective: UC is a chronic gastrointestinal disorder of uncertain etiology. However, effective therapeutic drug options for UC are relatively limited. Fraxin represents a principal active constituent within the traditional Chinese medicinal herb known as Cortex Fraxini or Qinpi. Nevertheless, the impact of Fraxin on UC remains uncharted. This study aims to explore the potential of Fraxin, a key component of Cortex Fraxini, in inhibiting DSS-induced intestinal inflammation in mice and to unravel the underlying mechanisms. Methods: In vitro experiment,the RAW264. 7 cells were induced by LPS as the model.In vivo experiment,the mice were induced by DSS as the animal model for a ten day experiment.The ELISA, western blots, measurement of oxidative stress markers and other relevant methods were used to discuss the effect of Fraxin on LPS-induced RAW264.7 cells and the inhibitory effect of Fraxin on intestinal inflammation induced by DSS in mice and underlying mechanisms. Results: Our findings indicated that Fraxin significantly reduced symptoms of UC, such as body weight loss, colonic length shortening, and histological damage. At the molecular level, it inhibited ROS generation, reduced pro-inflammatory cytokines, and regulated key pathways including TLR4/NF-κB and MAPK.The findings indicated that Fraxin diminished the expression of p-NF-κB and p-IκB, downregulated iNOS and COX-2 expression, and lessened p38, JNK and ERK phosphorylation. Conclusion: Taken together, Fraxin ameliorates UC by regulating oxidative stress, inflammation, and TLR4/NF-κB and MAPK pathways, and Fraxin may be a new treatment for UC. Our findings suggest that Fraxin could offer a novel therapeutic approach for UC, targeting oxidative stress and key inflammatory pathways.

Haplotype-phased genome unveils the butylphthalide biosynthesis and homoploid hybrid origin of Ligusticum chuanxiong.

Butylphthalide is one of the first-line drugs for ischemic stroke therapy, while no biosynthetic enzyme for butylphthalide has been reported. Here, we present a haplotype-resolved genome of Ligusticum chuanxiong, a long-cultivated and phthalide-rich medicinal plant in Apiaceae. On the basis of comprehensive screening, four Fe(II)- and 2-oxoglutarate-dependent dioxygenases and two CYPs were mined and further biochemically verified as phthalide C-4/C-5 desaturases (P4,5Ds) that effectively promoted the forming of (S)-3-n-butylphthalide and butylidenephthalide. The substrate promiscuity and functional redundancy featured for P4,5Ds may contribute to the high phthalide diversity in L. chuanxiong. Notably, comparative genomic evidence supported L. chuanxiong as a homoploid hybrid with Ligusticum sinense as a potential parent. The two haplotypes demonstrated exceptional structure variance and diverged around 3.42 million years ago. Our study is an icebreaker for the dissection of phthalide biosynthetic pathway and reveals the hybrid origin of L. chuanxiong, which will facilitate the metabolic engineering for (S)-3-n-butylphthalide production and breeding for L. chuanxiong.

LcSAO1, an Unconventional DOXB Clade 2OGD Enzyme from Ligusticum chuanxiong Catalyzes the Biosynthesis of Plant-Derived Natural Medicine Butylphthalide.

Butylphthalide, a prescription medicine recognized for its efficacy in treating ischemic strokes approved by the State Food and Drug Administration of China in 2005, is sourced from the traditional botanical remedy Ligusticum chuanxiong. While chemical synthesis offers a viable route, limitations in the production of isomeric variants with compromised bioactivity necessitate alternative strategies. Addressing this issue, biosynthesis offers a promising solution. However, the intricate in vivo pathway for butylphthalide biosynthesis remains elusive. In this study, we examined the distribution of butylphthalide across various tissues of L. chuanxiong and found a significant accumulation in the rhizome. By searching transcriptome data from different tissues of L. chuanxiong, we identified four rhizome-specific genes annotated as 2-oxoglutarate-dependent dioxygenase (2-OGDs) that emerged as promising candidates involved in butylphthalide biosynthesis. Among them, LcSAO1 demonstrates the ability to catalyze the desaturation of senkyunolide A at the C-4 and C-5 positions, yielding the production of butylphthalide. Experimental validation through transient expression assays in Nicotiana benthamiana corroborates this transformative enzymatic activity. Notably, phylogenetic analysis of LcSAO1 revealed that it belongs to the DOXB clade, which typically encompasses genes with hydroxylation activity, rather than desaturation. Further structure modelling and site-directed mutagenesis highlighted the critical roles of three amino acid residues, T98, S176, and T178, in substrate binding and enzyme activity. By unraveling the intricacies of the senkyunolide A desaturase, the penultimate step in the butylphthalide biosynthesis cascade, our findings illuminate novel avenues for advancing synthetic biology research in the realm of medicinal natural products.

Hypoglycemic effect of triterpenoid-rich extracts from Euryale ferox shell on normal and streptozotocin-diabetic mice.

The antioxidant effects of the triterpenoid-rich extracts from Euryale ferox shell (ES) have been confirmed in vitro. This study examined whether the triterpenoid-rich extract from ES eases human hyperglycemia and diabetes caused by metabolic disorders. Normal and streptozocin (STZ)-induced diabetic mice were used as controls for the four groups that received the triterpenoid-rich extracts of ES suspended in distilled water orally at doses of 200, 300, 400, 500±2 mg/L. Body weight, blood glucose and pancreatic tissue morphology were observed after 4 weeks. The expression of protein tyrosine phosphatase-1B (PTP1B) and insulin receptor substrate (IRS-1) proteins, which are related to the regulation of glucose metabolism in vivo, were also investigated. Compared with the model group (LD50 900±2 mg/L), it was found that the triterpenoid-rich extracts of ES could regulate glucose metabolism (P<0.01) and cause body weight to return to normal levels (P<0.05). Islet morphology recovered well, the expression of the negative regulation protein PTP1B gene was reduced and insulin receptor IRS-1 protein expression was increased. These data prove that the triterpenoid-rich extracts from ES have a therapeutic effect on diabetes by insulin resistance.