Eupatilin Impacts on the Progression of Colon Cancer by Mitochondria Dysfunction and Oxidative Stress

Small molecule treatment alleviates photoreceptor cilia defects in LCA5-deficient human retinal organoids

Bialleleic pathogenic variants in LCA5 cause one of the most severe forms of Leber congenital amaurosis, an early-onset retinal disease that results in severe visual impairment. Here, we report the use of gene editing to generate isogenic LCA5 knock-out (LCA5 KO) induced pluripotent stem cells (iPSC) and their differentiation to retinal organoids. The molecular and cellular phenotype of the LCA5 KO retinal organoids was studied in detail and compared to isogenic controls as well as patient-derived retinal organoids. The absence of LCA5 was confirmed in retinal organoids by immunohistochemistry and western blotting. There were no major changes in retinal organoid differentiation or ciliation, however, the localisation of CEP290 and IFT88 was significantly altered in LCA5 KO and patient photoreceptor cilia with extension along the axoneme. The LCA5-deficient organoids also had shorter outer segments and rhodopsin was mislocalised to the outer nuclear layer. We also identified transcriptomic and proteomic changes associated with the loss of LCA5. Importantly, treatment with the small molecules eupatilin, fasudil or a combination of both drugs reduced CEP290 and IFT88 accumulation along the cilia. The treatments also improved rhodopsin traffic to the outer segment and reduced mislocalisation of rhodopsin in the outer nuclear layer (ONL). The improvements in cilia-associated protein localisation and traffic were accompanied by significant changes in the transcriptome towards control gene expression levels in many of the differentially expressed genes. In summary, iPSC-derived retinal organoids are a powerful model for investigating the molecular and cellular changes associated with loss of LCA5 function and highlight the therapeutic potential of small molecules to treat retinal ciliopathies.

Eupatilin suppresses osteoclastogenesis and periodontal bone loss by inhibiting the MAPKs/Siglec-15 pathway

Periodontitis is a widely prevalent oral disease around the world characterized by the disruption of the periodontal ligament and the subsequent development of periodontal pockets, as well as the loss of alveolar bone, and may eventually lead to tooth loss. This research aims to assess the suppressive impact of Eupatilin, a flavone obtained from Artemisia argyi, on osteoclastogenesis in vitro and periodontitis in vivo. We found that Eupatilin can efficiently obstruct the differentiation of Raw264.7 and bone marrow-derived macrophages (BMDMs) induced by RANKL, leading to the formation of mature osteoclasts. Consistently, bone slice resorption assay showed that Eupatilin significantly inhibited osteoclast-mediated bone resorption in a dose-dependent manner. Eupatilin also downregulated the expression of osteoclast-specific genes and proteins in Raw264.7 and BMDMs. RNA sequencing showed that Eupatilin notably downregulated the expression of Siglec-15. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses identified significantly enriched pathways in DEGs, including MAPK signaling pathway. And further mechanistic investigations confirmed that Eupatilin repressed MAPKs/NF-κBsignaling pathways. It was found that Siglec-15 overexpression reversed the inhibitory impact of Eupatilin on the differentiation of osteoclasts. Furthermore, activating MAPK signaling pathway reversed the downregulation of Siglec-15 and the inhibition of osteoclastogenesis by Eupatilin. To sum up, Eupatilin reduced the expression of Siglec-15 by suppressing MAPK signaling pathway, ultimately leading to the inhibition of osteoclastogenesis. Meanwhile, Eupatilin suppressed the alveolar bone resorption caused by experimentalperiodontitis in vivo. Eupatilin exhibits potential therapeutic effects in the treatment of periodontitis, rendering it a promising pharmaceutical agent.

Eupatilin inhibits xanthine oxidase in vitro and attenuates hyperuricemia and renal injury in vivo

Uric acid (UA) is the final metabolite of purines in the liver that can cause hyperuricemia at high levels. The kidneys are the main excretory organs for UA. The excessive accumulation of UA in the kidneys causes the development of hyperuricemia that often leads to renal injury. Eupatilin (Eup) is a flavonoid natural product that possesses various pharmacological properties such as antioxidant, anti-cancer, and anti-inflammatory. We were interested in exploring the potential role of Eup in lowering UA and nephroprotective. We initially investigated the effects of Eup on xanthin oxidase (XOD) activity in vitro, followed by investigating its ability to lower UA levels, anti-inflammatory effects, nephroprotective effects, and the underlying mechanisms using hyperuricemia rats sustained at high UA level. The results showed that Eup had an inhibitory effect on XOD activity in vitro and significantly reduced serum UA, creatinine, BUN, IL-1β and IL-6 levels in hyperuricemic rats, ameliorating inflammation, renal oxidative stress and pathological injury. Furthermore, Eup inhibited ADA and XOD enzyme activities in the liver and serum and modulated GLUT9, URAT1 and ABCG2 protein expression in the kidneys and ileum. Our findings provide a scientific basis for suggesting Eup as an option for a potential treatment for hyperuricemia.

Eupatilin Improves Cilia Defects in Human CEP290 Ciliopathy Models

The photoreceptor outer segment is a highly specialized primary cilium that is essential for phototransduction and vision. Biallelic pathogenic variants in the cilia-associated gene CEP290 cause non-syndromic Leber congenital amaurosis 10 (LCA10) and syndromic diseases, where the retina is also affected. While RNA antisense oligonucleotides and gene editing are potential treatment options for the common deep intronic variant c.2991+1655A>G in CEP290, there is a need for variant-independent approaches that could be applied to a broader spectrum of ciliopathies. Here, we generated several distinct human models of CEP290-related retinal disease and investigated the effects of the flavonoid eupatilin as a potential treatment. Eupatilin improved cilium formation and length in CEP290 LCA10 patient-derived fibroblasts, in gene-edited CEP290 knockout (CEP290 KO) RPE1 cells, and in both CEP290 LCA10 and CEP290 KO iPSCs-derived retinal organoids. Furthermore, eupatilin reduced rhodopsin retention in the outer nuclear layer of CEP290 LCA10 retinal organoids. Eupatilin altered gene transcription in retinal organoids by modulating the expression of rhodopsin and by targeting cilia and synaptic plasticity pathways. This work sheds light on the mechanism of action of eupatilin and supports its potential as a variant-independent approach for CEP290-associated ciliopathies.

Eupatilin improves cilia defects in human CEP290 ciliopathy models

The photoreceptor outer segment is a highly specialized primary cilium essential for phototransduction and vision. Biallelic pathogenic variants in the cilia-associated gene CEP290 cause non-syndromic Leber congenital amaurosis 10 (LCA10) and syndromic diseases, where the retina is also affected. While RNA antisense oligonucleotides and gene editing are potential treatment options for the common deep intronic variant c.2991+1655A>G in CEP290 , there is a need for variant-independent approaches that could be applied to a broader spectrum of ciliopathies. Here, we generated several distinct human models of CEP290 -related retinal disease and investigated the effects of the flavonoid eupatilin as a potential treatment. Eupatilin improved cilium formation and length in CEP290 LCA10 patient-derived fibroblasts, in gene-edited CEP290 knockout (CEP290 KO) RPE1 cells, and in both CEP290 LCA10 and CEP290 KO iPSCs-derived retinal organoids. Furthermore, eupatilin reduced rhodopsin retention in the outer nuclear layer of CEP290 LCA10 retinal organoids. Eupatilin altered gene transcription in retinal organoids, by modulating the expression of rhodopsin, and by targeting cilia and synaptic plasticity pathways. This work sheds light into the mechanism of action of eupatilin, and supports its potential as a variant-independent approach for CEP290 -associated ciliopathies.

Abstract Figure

Global Trends in Research of Mitochondrial Biogenesis over past 20 Years: A Bibliometric Analysis

Background

Mitochondrial biogenesis-related studies have increased rapidly within the last 20 years, whereas there has been no bibliometric analysis on this topic to reveal relevant progress and development trends.

Objectives

In this study, a bibliometric approach was adopted to summarize and analyze the published literature in this field of mitochondrial biogenesis over the past 20 years to reveal the major countries/regions, institutions and authors, core literature and journal, research hotspots and frontiers in this field.

Methods

The Web of Science Core Collection database was used for literature retrieval and dataset export. The CiteSpace and VOSviewer visual mapping software were used to explore research collaboration between countries/regions, institutions and authors, distribution of subject categories, core journals, research hotspots, and frontiers in this field.

Results

In the last 20 years, the annual number of publications has shown an increasing trend yearly. The USA, China, and South Korea have achieved fruitful research results in this field, among which Duke University and Chinese Academy of Sciences are the main research institutions. Rick G Schnellmann, Claude A Piantadosi, and Hagir B Suliman are the top three authors in terms of number of publications, while RC Scarpulla, ZD Wu, and P Puigserver are the top three authors in terms of cocitation frequency. PLOS One, Biochemical and Biophysical Research Communications, and Journal of Biological Chemistry are the top three journals in terms of number of articles published. Three papers published by Richard C Scarpulla have advanced this field and are important literature for understanding the field. Mechanistic studies on mitochondrial biosynthesis have been a long-standing hot topic; the main keywords include skeletal muscle, oxidative stress, gene expression, activation, and nitric oxide, and autophagy and apoptosis have been important research directions in recent years.

Conclusion

These results summarize the major research findings in the field of mitochondrial biogenesis over the past 20 years in various aspects, highlighting the major research hotspots and possible future research directions and helping researchers to quickly grasp the overview of the developments in this field.

Targeting Thymidylate Synthase and tRNA-Derived Non-Coding RNAs Improves Therapeutic Sensitivity in Colorectal Cancer

Some colorectal cancer (CRC) patients are resistant to 5-fluorouracil (5-FU), and high expression levels of thymidylate synthase (TS) contribute to this resistance. This study investigated whether quercetin, a representative polyphenol compound, could enhance the effect of 5-FU in CRC cells. Quercetin suppressed TS levels that were increased by 5-FU in CRC cells and promoted the expression of p53. Quercetin also induced intracellular and mitochondrial reactive oxygen species (ROS) production and Ca2+ dysregulation in a 5-FU-independent pathway in CRC cells. Furthermore, quercetin decreased mitochondrial membrane potential in CRC cells and inhibited mitochondrial respiration. Moreover, quercetin regulated the expression of specific tiRNAs, including tiRNAHisGTG, and transfection of a tiRNAHisGTG mimic further enhanced the apoptotic effect of quercetin in CRC cells. An enhanced sensitivity to 5-FU was also confirmed in colitis-associated CRC mice treated with quercetin. The treatment of quercetin decreased survival rates of the CRC mouse model, with reductions in the number of tumors and in the disease activity index. Also, quercetin suppressed TS and PCNA protein expression in the distal colon tissue of CRC mice. These results suggest that quercetin has the potential to be used as an adjuvant with 5-FU for the treatment of CRC.

Polydatin Counteracts 5-Fluorouracil Resistance by Enhancing Apoptosis via Calcium Influx in Colon Cancer

Colon cancer is a disease with a high prevalence rate worldwide, and for its treatment, a 5-fluorouracil (5-FU)-based chemotherapeutic strategy is generally used. However, conventional anticancer agents have some limitations, including the development of drug resistance. Therefore, there has recently been a demand for the improvement of antitumor agents using natural products with low side effects and high efficacy. Polydatin is a natural active compound extracted from an annual plant, and widely known for its anticancer effects in diverse types of cancer. However, it is still not clearly understood how polydatin ameliorates several drawbacks of standard anticancer drugs by reinforcing the chemosensitivity against 5-FU, and neither are the intrinsic mechanisms behind this process. In this study, we examined how polydatin produces anticancer effects in two types of colon cancer, called HCT116 and HT-29 cells. Polydatin has the ability to repress the progression of colon cancer, and causes a modification of distribution in the cell cycle by a flow cytometry analysis. It also induces mitochondrial dysfunctions through oxidative stress and the loss of mitochondrial membrane potential. The present study investigated the apoptosis caused by the disturbance of calcium regulation and the expression levels of related proteins through flow cytometry and immunoblotting analysis. It was revealed that polydatin suppresses the signaling pathways of the mitogen-activated protein kinase (MAPK) and PI3K/AKT. In addition, it was shown that polydatin combined with 5-FU counteracts drug resistance in 5-FU-resistant cells. Therefore, this study suggests that polydatin has the potential to be developed as an innovative medicinal drug for the treatment of colon cancer.