Total iridoid glycoside extract of Lamiophlomis rotata (Benth) Kudo accelerates diabetic wound healing by the NRF2/COX2 axis.

BACKGROUND: Lamiophlomis rotata (Benth.) Kudo (L. rotata), the oral Traditional Tibetan herbal medicine, is adopted for treating knife and gun wounds for a long time. As previously demonstrated, total iridoid glycoside extract of L. rotata (IGLR) induced polarization of M2 macrophage to speed up wound healing. In diabetic wounds, high levels inflammatory and chemotactic factors are usually related to high reactive oxygen species (ROS) levels. As a ROS target gene, nuclear factor erythroid 2-related factor 2 (NRF2), influences the differentiation of monocytes to M1/M2 macrophages. Fortunately, iridoid glycosides are naturally occurring active compounds that can be used as the oxygen radical scavenger. Nevertheless, the influence of IGLR in diabetic wound healing and its associated mechanism is largely unclear. MATERIALS AND METHODS: With macrophages and dermal fibroblasts in vitro, as well as a thickness excision model of db/db mouse in vivo, the role of IGLR in diabetic wound healing and the probable mechanism of the action were investigated. RESULTS: Our results showed that IGLR suppressed oxidative distress and inflammation partly through the NRF2/cyclooxygenase2 (COX2) signaling pathway in vitro. The intercellular communication between macrophages and dermal fibroblasts was investigated by the conditioned medium (CM) of IGLR treatment cells. The CM increased the transcription and translation of collagen I (COL1A1) and alpha smooth muscle actin (α-SMA) within fibroblasts. With diabetic wound mice, the data demonstrated IGLR activated the NRF2/KEAP1 signaling and the downstream targets of the pathway, inhibited COX2/PEG2 signaling and decreased the interaction inflammatory targets of the axis, like interleukin-1beta (IL-1ß), interleukin 6 (IL-6), apoptosis-associated speck-like protein (ASC), cysteinyl aspartate specific proteinase1 (caspase1) and NOD-like receptor-containing protein 3 (NLRP3).In addition, the deposition of COL1A1, and the level of α-SMA, and Transforming growth factor-ß1 (TGF-ß1) obviously elevated, whereas that of pro-inflammatory factors reduced in the diabetic wound tissue with IGLR treatment. CONCLUSION: IGLR suppressed oxidative distress and inflammation mainly through NRF2/COX2 axis, thus promoting paracrine and accelerating wound healing in diabetes mice.

Transcriptomic and proteomic investigation of the ameliorative effect of total polyphenolic glycoside extract on hepatic fibrosis in Lamiophlomis rotata Kudo via the AGE/RAGE pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: During the regression of liver fibrosis, a decrease in hepatic stellate cells (HSCs) can occur through apoptosis or inactivation of activated HSCs (aHSCs). A new approach for antifibrotic therapy involves transforming hepatic myofibroblasts into a quiescent-like state. Lamiophlomis rotata (Benth.) Kudo (L. rotata), an orally available Tibetan herb, has traditionally been used to treat skin disease, jaundice, and rheumatism. In our previous study, we found that the total polyphenolic glycoside extract of L. rotata (TPLR) promotes apoptosis in aHSCs for the treatment of hepatic fibrosis. However, whether TPLR induces aHSCs to become inactivated HSCs (iHSCs) is unclear, and the underlying mechanism remains largely unknown. PURPOSE: This study aimed to examine the impact of TPLR on the phenotypes of hepatic stellate cells (HSCs) during the regression of liver fibrosis and explore the potential mechanism of action. METHODS: The effect of TPLR on the phenotypes of hepatic stellate cells (HSCs) was assessed using immunofluorescence (IF) staining, reverse transcription-polymerase chain reaction (RT-PCR), and Western blotting. Transcriptomic and proteomic methods were employed to identify the main signaling pathways involved. Based on the omics results, the likely mechanism of TPLR on the phenotypes of aHSCs was confirmed through overexpression and knockdown experiments in TGF-ß1-activated LX-2 cells. Using a CCl4-induced liver fibrosis mouse model, we evaluated the anti-hepatic fibrosis effect of TPLR and explored its potential mechanism based on omics findings. RESULTS: TPLR was found to induce the differentiation of aHSCs into iHSCs by significantly decreasing the protein expression of α-SMA and Desmin. Transcriptomic and proteomic analyses revealed that the AGE/RAGE signaling pathway plays a crucial role in the morphological transformation of HSCs following TPLR treatment. In vitro experiments using RAGE overexpression and knockdown demonstrated that the mechanism by which TPLR affects the phenotype of HSCs is closely associated with the RAGE/RAS/MAPK/NF-κB axis. In a model of liver fibrosis, TPLR obviously inhibited the generation of AGEs and alleviated liver tissue damage and fibrosis by downregulating RAGE and its downstream targets. CONCLUSION: The AGE/RAGE axis plays a pivotal role in the transformation of activated hepatic stellate cells (aHSCs) into inactivated hepatic stellate cells (iHSCs) following TPLR treatment, indicating the potential of TPLR as a therapeutic agent for the management of liver fibrosis.

The total iridoid glycoside extract of Lamiophlomis rotata Kudo induces M2 macrophage polarization to accelerate wound healing by RAS/ p38 MAPK/NF-κB pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Lamiophlomis rotata (Benth.) Kudo (L. rotata), a Tibetan medicinal plant, is used to treat "yellow-water diseases", such as skin disease, jaundice and rheumatism. Our previous study showed that the iridoid glycoside extract of L. rotata (IGLR) is the major constituent of skin wound healing. However, the role of IGLR in the biological process of trauma repair and the probable mechanism of the action remain largely unknown. AIM OF THE STUDY: To investigate the role of IGLR in the biological process of trauma repair and the probable mechanism of the action. MATERIALS AND METHODS: The role of IGLR in wound healing was investigated by overall skin wound in mice with Hematoxylin and Eosin (H&E) and Masson trichrome staining. The anti-inflammatory, angiogenesis-promoting and fibril formation effects of IGLR were visualized in wound skin tissue by immunofluorescence staining, and the proinflammatory factors and growth factors were assayed by real-time polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Macrophages, dermal fibroblasts, and endothelial cells were cultured to measure the direct/indirect interaction effects of IGLR on the proliferation and migration of cells, and flow cytometry was employed to assess the role of IGLR on macrophage phenotype. Network pharmacology combined with Western blot experiments were conducted to explore possible mechanisms of the actions. RESULTS: IGLR increased the expression of CD206 (M2 markers) through the RAS/p38 MAPK/NF-κB signaling pathway during wound injury in vivo and in vitro. IGLR suppressed the inflammatory cytokines iNOS, IL-1ß and TNF-α in the early stage of wound healing. During the proliferation step of wound repair, IGLR promoted angiogenesis and fibril formation by increasing the expression of VEGF, CD31, TGF-ß and α-SMA in wound tissue, and similar results were verified by RT-PCR and ELISA. In a paracrine mechanism, the extract promoted the proliferation of dermal fibroblasts, and endothelial cells were founded by the conditioned medium (CM). CONCLUSION: IGLR induced M2 macrophage polarization in the early stage of wound healing; in turn, IGLR played a key role in the transition from inflammation to cell proliferation during the biological process of wound healing.

The total polyphenolic glycoside extract of Lamiophlomis rotata ameliorates hepatic fibrosis through apoptosis by TGF-ß/Smad signaling pathway.

BACKGROUND: Hepatic fibrosis is characterized by the excessive deposition of extracellular matrix (ECM) which is mainly secreted by activated hepatic stellate cells (HSCs). Lamiophlomis rotata (L. rotata) was recorded to treat jaundice in the traditional Tibetan medical system with the potential of hepatoprotection. However, the bioactivities and the possible mechanism of L. rotata on hepatic fibrosis is still largely unknown. AIM OF THE STUDY: To investigate the anti-hepatic fibrosis effects of bioactivities in L. rotata and the probable mechanism of action. MATERIALS AND METHODS: Herein, total polyphenolic glycosides of L. rotata (TPLR) was purified with the selectivity adsorption resin and was analyzed by ultrahigh-performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-Q/TOF/MSn). The anti-hepatic fibrosis effect of TPLR was evaluated by carbon tetrachloride (CCl4)-induced liver fibrosis, and was evaluated with the apoptosis of activated HSCs. RESULTS: In total, sixteen compounds, including nine phenylpropanoids and six flavonoids, were identified in the UPLC-TOF-MSn profile of the extracts. TPLR significantly ameliorated hepatic fibrosis in CCl4-induced mice and inhibited HSCs proliferation, Moreover, TPLR notably increased the apoptosis of activated HSCs along with up-regulated caspase-3, -8, -9, and -10. Furthermore, TPLR inhibited TGF-ß/Smad pathway ameliorating hepatic fibrosis though downregulation the expression of Smad2/3, Smad4, and upregulation the expression of Smad7 in vivo and in vitro. Simultaneously, the expression of fibronectin (FN), α-smooth muscle actin (α-SMA), and Collagen I (Col1α1) were decreased in tissues and in cells with TPLR administration. CONCLUSION: These results initially demonstrated that TPLR has the potential to ameliorate hepatic fibrosis through an apoptosis mechanism via TGF-ß/Smad signaling pathway.

TAA1-regulated local auxin biosynthesis in the root-apex transition zone mediates the aluminum-induced inhibition of root growth in Arabidopsis.

The transition zone (TZ) of the root apex is the perception site of Al toxicity. Here, we show that exposure of Arabidopsis thaliana roots to Al induces a localized enhancement of auxin signaling in the root-apex TZ that is dependent on TAA1, which encodes a Trp aminotransferase and regulates auxin biosynthesis. TAA1 is specifically upregulated in the root-apex TZ in response to Al treatment, thus mediating local auxin biosynthesis and inhibition of root growth. The TAA1-regulated local auxin biosynthesis in the root-apex TZ in response to Al stress is dependent on ethylene, as revealed by manipulating ethylene homeostasis via the precursor of ethylene biosynthesis 1-aminocyclopropane-1-carboxylic acid, the inhibitor of ethylene biosynthesis aminoethoxyvinylglycine, or mutant analysis. In response to Al stress, ethylene signaling locally upregulates TAA1 expression and thus auxin responses in the TZ and results in auxin-regulated root growth inhibition through a number of auxin response factors (ARFs). In particular, ARF10 and ARF16 are important in the regulation of cell wall modification-related genes. Our study suggests a mechanism underlying how environmental cues affect root growth plasticity through influencing local auxin biosynthesis and signaling.