Focus on Notoginsenoside R1 in Metabolism and Prevention Against Human Diseases

Characterization of a Xylosyltransferase from Panax notoginseng Catalyzing Ginsenoside 2'-O Glycosylation in the Biosynthesis of Notoginsenosides

Notoginsenosides are important bioactive compounds from Panax notoginseng (Burk.) F. H. Chen, most of which have xylose in their sugar chains. However, the xylosyltransferases involved in the generation of notoginsenosides remain poorly understood, posing a bottleneck for further study of the biosynthesis of notoginsenosides. In this work, a new xylosyltransferase gene, PnUGT57 (named UGT94BW1), was identified from P. notoginseng, which has a distinct sequence and could catalyze the 2'-O glycosylation of ginsenosides Rh1 and Rg1 to produce notoginsenosides R2 and R1, respectively. We first characterized the optimal conditions for the PnUGT57 activity and its enzymatic kinetic parameters, and then, molecular docking and site-directed mutagenesis were performed to elucidate the catalytic mechanism of PnUGT57. Combined with the results of site-directed mutagenesis, Glu26, Ser266, Glu267, Trp347, Ser348, and Glu352 in PnUGT57 were identified as the key residues involved in 2'-O glycosylation of C-6 O-Glc, and PnUGT57R175A and PnUGT57G237A could significantly improve the catalytic activity of PnUGT57. These findings not only provide a new xylosyltransferase gene for augmenting the plant xylosyltransferase database but also identify the pivotal sites and catalytic mechanism of the enzyme, which would provide reference for the modification and application of xylosyltransferases in the future.

The signaling pathways of selected traditional Chinese medicine prescriptions and their metabolites in the treatment of diabetic cardiomyopathy: a review

Diabetic cardiomyopathy (DCM) is a myocardial-specific microvascular disease caused by diabetes that affects the structure and function of the heart and is considered to be the leading cause of morbidity and death in patients with diabetes. Currently, there is no specific treatment or preventive drug for DCM, and there is an urgent need to develop new drugs to treat DCM. Traditional Chinese medicine (TCM) has rich experience in the treatment of DCM, and its characteristics of multi-target, multi-pathway, multi-component, and few side effects can effectively deal with the complexity and long-term nature of DCM. Growing evidence suggests that myocardial fibrosis, inflammation, oxidative stress, apoptosis, cardiac hypertrophy, and advanced glycation end product deposition were the main pathologic mechanisms of DCM. According to the pathological mechanism of DCM, this study revealed the potential of metabolites and prescriptions in TCM against DCM from the perspective of signaling pathways. The results showed that TGF-β/Smad, NF-κB, PI3K/AKT, Nrf2, AMPK, NLRP3, and Wnt/β-catenin signaling pathways were the key signaling pathways for TCM treatment of DCM. The aim of this study was to summarize and update the signaling pathways for TCM treatment of DCM, to screen potential targets for drug candidates against DCM, and to provide new ideas and more experimental evidence for the clinical use of TCM treatment of DCM.

Conversion of notoginsenoside R1 to 3β,12β-dihydroxydammar-(E)-20(22),24-diene-6-O-β-D-xylopyranosyl-(1→2)-β-D-glucopyranoside by Lactiplantibacillus plantarum S165 enhanced protective effects of LPS-induced intestinal epithelial barrier injury in Caco-2 cells

AIMS

Microbial transformation to modify saponins and enhance their biological activities has received increasing attention in recent years. This study aimed to screen the strain that can biotransform notoginsenoside R1, identify the product and study its biological activity.

METHODS AND RESULTS

A lactic acid bacteria strain S165 with glycosidase-producing activity was isolated from traditional Chinese fermented foods, which was identified and grouped according to API 50 CHL kit and 16S rDNA sequence analysis. Subsequently, notoginsenoside R1 underwent a 30-day fermentation period by the strain S165, and the resulting products were analyzed using High-performance liquid chromatography (HPLC), Ultra-performance liquid chromatography (UPLC)-mass spectrometry (MS)/MS, and 13C-Nuclear magnetic resonance (NMR) techniques. Employing a model of Lipopolysaccharide (LPS)-induced damage to Caco-2 cells, the damage of Caco-2 cells was detected by Hoechst 33 258 staining, and the activity of notoginsenoside R1 biotransformation product was investigated by CCK-8 and western blotting assay. The strain S165 was identified as Lactiplantibacillus plantarum and was used to biotransform notoginsenoside R1. Through a 30-day biotransformation, L. plantarum S165 predominantly converts notoginsenoside R1 into 3β,12β-dihydroxydammar-(E)-20(22),24-diene-6-O-β-D-xylopyranosyl-(1→2)-β-D-glucopyranoside, temporarily named notoginsenoside T6 (NGT6) according to HPLC, UPLC-MS/MS, and 13C-NMR analysis. Results from CCK-8 and Hoechst 33258 staining indicated that the ability notoginsenoside T6 to alleviate the intestinal injury induced by LPS in the Caco-2 cell was stronger than that of notoginsenoside R1. In addition, Western blotting result showed that notoginsenoside T6 could prevent intestinal injury by protecting tight junction proteins (Claudin-1, Occludin, and ZO-1).

CONCLUSION

Notoginsenoside R1 was biotransformed into the notoginsenoside T6 by L. plantarum S165, and the biotransformed product showed an enhanced intestinal protective effect in vitro.

Notoginsenoside R1 promotes Lgr5+ stem cell and epithelium renovation in colitis mice via activating Wnt/β-Catenin signaling

Inflammatory bowel disease (IBD) is characterized by persistent damage to the intestinal barrier and excessive inflammation, leading to increased intestinal permeability. Current treatments of IBD primarily address inflammation, neglecting epithelial repair. Our previous study has reported the therapeutic potential of notoginsenoside R1 (NGR1), a characteristic saponin from the root of Panax notoginseng, in alleviating acute colitis by reducing mucosal inflammation. In this study we investigated the reparative effects of NGR1 on mucosal barrier damage after the acute injury stage of DSS exposure. DSS-induced colitis mice were orally treated with NGR1 (25, 50, 125 mg·kg-1·d-1) for 10 days. Body weight and rectal bleeding were daily monitored throughout the experiment, then mice were euthanized, and the colon was collected for analysis. We showed that NGR1 administration dose-dependently ameliorated mucosal inflammation and enhanced epithelial repair evidenced by increased tight junction proteins, mucus production and reduced permeability in colitis mice. We then performed transcriptomic analysis on rectal tissue using RNA-sequencing, and found NGR1 administration stimulated the proliferation of intestinal crypt cells and facilitated the repair of epithelial injury; NGR1 upregulated ISC marker Lgr5, the genes for differentiation of intestinal stem cells (ISCs), as well as BrdU incorporation in crypts of colitis mice. In NCM460 human intestinal epithelial cells in vitro, treatment with NGR1 (100 μM) promoted wound healing and reduced cell apoptosis. NGR1 (100 μM) also increased Lgr5+ cells and budding rates in a 3D intestinal organoid model. We demonstrated that NGR1 promoted ISC proliferation and differentiation through activation of the Wnt signaling pathway. Co-treatment with Wnt inhibitor ICG-001 partially counteracted the effects of NGR1 on crypt Lgr5+ ISCs, organoid budding rates, and overall mice colitis improvement. These results suggest that NGR1 alleviates DSS-induced colitis in mice by promoting the regeneration of Lgr5+ stem cells and intestinal reconstruction, at least partially via activation of the Wnt/β-Catenin signaling pathway. Schematic diagram of the mechanism of NGR1 in alleviating colitis. DSS caused widespread mucosal inflammation epithelial injury. This was manifested by the decreased expression of tight junction proteins, reduced mucus production in goblet cells, and increased intestinal permeability in colitis mice. Additionally, Lgr5+ ISCs were in obviously deficiency in colitis mice, with aberrant down-regulation of the Wnt/β-Catenin signaling. However, NGR1 amplified the expression of the ISC marker Lgr5, elevated the expression of genes associated with ISC differentiation, enhanced the incorporation of BrdU in the crypt and promoted epithelial restoration to alleviate DSS-induced colitis in mice, at least partially, by activating the Wnt/β-Catenin signaling pathway.

Multi-layered effects of Panax notoginseng on immune system

Recent research has demonstrated the immunomodulatory potential of Panax notoginseng in the treatment of chronic inflammatory diseases and cerebral hemorrhage, suggesting its significance in clinical practice. Nevertheless, the complex immune activity of various components has hindered a comprehensive understanding of the immune-regulating properties of Panax notoginseng, impeding its broader utilization. This review evaluates the effect of Panax notoginseng to various types of white blood cells, elucidates the underlying mechanisms, and compares the immunomodulatory effects of different Panax notoginseng active fractions, aiming to provide the theory basis for future immunomodulatory investigation.

Notoginsenoside R1 attenuates bupivacaine induced neurotoxicity by activating Jak1/Stat3/Mcl1 pathway

Bupivacaine, a common amide local anesthetic, can provide effective analgesia or pain relief but can also cause neurotoxicity, which remains a mounting concern in clinic and animal care. However, the precise underlying mechanisms have not been fully elucidated. A natural compound, notoginsenoside R1 (NG-R1) has been reported to exhibit a neuroprotective role in stress conditions. In this study, we explored the function and mechanism of NG-R1 in alleviating bupivacaine-induced neurotoxicity in mouse hippocampal neuronal (HT-22) and mouse neuroblastoma (Neuro-2a) cell lines. Our results exhibited that NG-R1 treatment can significantly rescue the decline of cell survival induced by bupivacaine. Tunel staining and western blotting showed that NG-R1 could attenuate BPV‑induced cell apoptosis. Besides, we focused on Mcl1 as a potential target as it showed opposite expression tendency in response to NG-R1 and bupivacaine exposure. Mcl1 knockdown blocked the inhibitory effect of NG-R1 on cell apoptosis against bupivacaine treatment. Intriguingly, we found that NG-R1 can upregulate Mcl1 transcription by activating Stat3 and promote its nuclear translocation. In addition, NG-R1 can also promote Jak1 phosphorylation and docking analysis provide a predicted model for interaction between NG-R1 and phosphorylated Jak1. Taken together, our results demonstrated that NG-R1 can attenuate bupivacaine induced neurotoxicity by activating Jak1/Stat3/Mcl1 pathway.

The characteristics and molecular targets of antiarrhythmic natural products

Arrhythmia is one of the most common cardiovascular diseases. The search for new drugs to suppress various types of cardiac arrhythmias has always been the focus of attention. In the past decade, the screening of antiarrhythmic active substances from plants has received extensive attention. These natural compounds have obvious antiarrhythmic effects, and chemical modifications based on natural compounds have greatly increased their pharmacological properties. The chemical modification of botanical antiarrhythmic drugs is closely related to the development of new and promising drugs. Therefore, the structural characteristics and action targets of natural compounds with antiarrhythmic effects are reviewed in this paper, so that pharmacologists can select antiarrhythmic lead compounds from natural compounds based on the disease target - chemical structural characteristics.

Notoginsenoside-R1 ameliorates palmitic acid-induced insulin resistance and oxidative stress in HUVEC via Nrf2/ARE pathway

Panax notoginseng, a Chinese traditional food and herb medicine, possesses notable cardiovascular health-promoting properties, with notoginsenoside (NG)-R1 being a key active compound. Insulin resistance represents a global health concern associated with various metabolic disorders. This study investigated the effects of NG-R1 on palmitic acid (PA)-induced insulin resistance and oxidative stress in human umbilical vein endothelial cells (HUVECs). Our findings demonstrate that NG-R1 significantly alleviated impaired glucose uptake, enhanced the phosphorylation of protein kinase B (PKB/Akt) at Ser473, and reduced the phosphorylation of insulin receptor substrate 1 (IRS-1) at Ser307 in PA-treated HUVECs. Furthermore, NG-R1 treatment significantly lowered the levels of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), while increasing the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG). Additionally, NG-R1 activated the Nrf2/ARE signaling pathway, leading to a substantial increase in the expression of antioxidant enzymes. Notably, knockdown of Nrf2 attenuated the beneficial effects of NG-R1 on PA-induced insulin resistance and oxidative stress in HUVECs, suggesting that NG-R1 exerts its effects through the Nrf2/ARE pathway. In summary, our study reveals that NG-R1 ameliorated PA-induced insulin resistance in HUVECs via Nrf2/ARE pathway, providing novel insights into its potential for alleviating metabolic disorders and cardiovascular disease.

Notoginsenoside R1 protects against hypobaric hypoxia-induced high-altitude pulmonary edema by inhibiting apoptosis via ERK1/2-P90rsk-BAD ignaling pathway

High-altitude pulmonary edema (HAPE) is a potentially fatal disease. Notoginsenoside R1 is a novel phytoestrogen with anti-inflammatory, antioxidant and anti-apoptosis properties. However, its effects and underlying mechanisms in the protection of hypobaric hypoxia-induced HAPE rats remains unclear. This study aimed to explore the protective effects and underlying mechanisms of Notoginsenoside R1 in hypobaric hypoxia-induced HAPE. We found that Notoginsenoside R1 alleviated the lung tissue injury, decreased lung wet/dry ratio, and reduced inflammation and oxidative stress. Additionally, Notoginsenoside R1 ameliorated the changes in arterial blood gas, decreased the total protein concentration in bronchoalveolar lavage fluid, and inhibited the occurrence of apoptosis caused by HAPE. In the process of further exploration of the mechanism, it was found that Notoginsenoside R1 could promote the activation of ERK1/2-P90rsk-BAD signaling pathway, and the effect of Notoginsenoside R1 was attenuated after the use of ERK1/2 inhibitor U0126. Our study indicated that the protective effects of Notoginsenoside R1 against HAPE were mainly related to the inhibition of inflammation, oxidative stress, and apoptosis. Notoginsenoside R1 may be a potential candidate for preventing HAPE.

Pretreatment with Notoginsenoside R1 attenuates high-altitude hypoxia-induced cardiac injury via activation of the ERK1/2-P90RSK-Bad signaling pathway in rats

High-altitude cardiac injury (HACI) is one of the common tissue injuries caused by high-altitude hypoxia that may be life threatening. Notoginsenoside R1 (NG-R1), a major saponin of Panax notoginseng, exerts anti-oxidative, anti-inflammatory, and anti-apoptosis effects, protecting the myocardium from hypoxic injury. This study aimed to investigate the protective effect and molecular mechanism of NG-R1 against HACI. We simulated a 6000 m environment for 48 h in a hypobaric chamber to create a HACI rat model. Rats were pretreated with NG-R1 (50, 100 mg/kg) or dexamethasone (4 mg/kg) for 3 days and then placed in the chamber for 48 h. The effect of NG-R1 was evaluated by changes in Electrocardiogram parameters, histopathology, cardiac biomarkers, oxidative stress and inflammatory indicators, key protein expression, and immunofluorescence. U0126 was used to verify whether the anti-apoptotic effect of NG-R1 was related to the activation of ERK pathway. Pretreatment with NG-R1 can improve abnormal cardiac electrical conduction and alleviate high-altitude-induced tachycardia. Similar to dexamethasone, NG-R1 can improve pathological damage, reduce the levels of cardiac injury biomarkers, oxidative stress, and inflammatory indicators, and down-regulate the expression of hypoxia-related proteins HIF-1α and VEGF. In addition, NG-R1 reduced cardiomyocyte apoptosis by down-regulating the expression of apoptotic proteins Bax, cleaved caspase 3, cleaved caspase 9, and cleaved PARP1 and up-regulating the expression of anti-apoptotic protein Bcl-2 through activating the ERK1/2-P90RSK-Bad pathway. In conclusion, NG-R1 prevented HACI and suppressed apoptosis via activation of the ERK1/2-P90RSK-Bad pathway, indicating that NG-R1 has therapeutic potential to treat HACI.

Streptomyces albidoflavus Q antifungal metabolites inhibit the ergosterol biosynthesis pathway and yeast growth in fluconazole-resistant Candida glabrata: phylogenomic and metabolomic analyses

There is an urgent need to develop new antifungals due to the increasing prevalence of multidrug-resistant fungal infections and the recent emergence of COVID-19-associated candidiasis. A good study model for evaluating new antifungal compounds is Candida glabrata, an opportunistic fungal pathogen with intrinsic resistance to azoles (the most common clinical drugs for treating fungal infections). The aim of the current contribution was to conduct in vitro tests of antifungal metabolites produced by the bacteria Streptomyces albidoflavus Q, identify their molecular structures, and utilize several techniques to provide evidence of their therapeutic target. S. albidoflavus was isolated from maize rhizospheric soil in Mexico and identified by phylogenomic analysis using a 92-gene core. Of the 66 metabolites identified in S. albidoflavus Q by a liquid chromatography-high resolution mass spectrometry (LC-HRMS) metabolomic analysis of the lyophilized supernatant, six were selected by the Way2drug server based on their in silico binding to the likely target, 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR, the key enzyme in the ergosterol biosynthesis pathway). Molecular modeling studies show a relatively high binding affinity for the CgHMGR enzyme by two secondary metabolites: isogingerenone B (diaryl heptanoid) and notoginsenoside J (polycyclic triterpene). These secondary metabolites were able to inhibit ergosterol synthesis and affect yeast viability in vitro. They also caused alterations in the ultrastructure of the yeast cytoplasmic membrane, as evidenced by transmission electron microscopy. The putative target of isogingerenone B and notoginsenoside J is distinct from that of azole drugs (the most common clinical antifungals). The target for the latter is the lanosterol 14 alpha-demethylase enzyme (Erg11). IMPORTANCE Multidrug resistance has emerged among yeasts of the genus Candida, posing a severe threat to global health. The problem has been exacerbated by the pandemic associated with COVID-19, during which resistant strains of Candida auris and Candida glabrata have been isolated from patients infected with the SARS-CoV-2 virus. To confront this challenge, the World Health Organization has invoked scientists to search for new antifungals with alternative molecular targets. This study identified 66 metabolites produced by the bacteria Streptomyces albidoflavus Q, 6 of which had promising properties for potential antifungal activity. The metabolites were tested in vitro as inhibitors of ergosterol synthesis and C. glabrata growth, with positive results. They were also found to damage the cytoplasmic membrane of the fungus. The corresponding molecular structures and their probable therapeutic target were established. The target is apparently distinct from that of azole drugs.

Molecular Mechanism Pathways of Natural Compounds for the Treatment of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world, and its incidence continues to increase each year. Yet, there is still no definitive drug that can stop its development. This review focuses mainly on lipotoxicity, oxidative stress, inflammation, and intestinal flora dysbiosis to understand NAFLD's pathogenesis. In this review, we used NCBI's PubMed database for retrieval, integrating in vivo and in vitro experiments to reveal the therapeutic effects of natural compounds on NAFLD. We also reviewed the mechanisms by which the results of these experiments suggest that these compounds can protect the liver from damage by modulating inflammation, reducing oxidative stress, decreasing insulin resistance and lipid accumulation in the liver, and interacting with the intestinal microflora. The natural compounds discussed in these papers target a variety of pathways, such as the AMPK pathway and the TGF-β pathway, and have significant therapeutic effects. This review aims to provide new possible therapeutic lead compounds and references for the development of novel medications and the clinical treatment of NAFLD. It offers fresh perspectives on the development of natural compounds in preventing and treating NAFLD.

Therapeutic targeting of Ras/Raf/MAPK pathway by natural products: A systematic and mechanistic approach for neurodegeneration

BACKGROUND

Multiple dysregulated pathways are behind the pathogenesis of neurodegenerative diseases (NDDs); however, the crucial targets are still unknown. Oxidative stress, apoptosis, autophagy, and inflammation are the most dominant pathways that strongly influence neurodegeneration. In this way, targeting the Ras/Raf/mitogen-activated protein kinases (MAPKs) pathway appears to be a developing strategy for combating NDDs like Parkinson's disease, Alzheimer's disease, stroke, aging, and other NDDs. Accordingly, plant secondary metabolites have shown promising potentials for the simultaneous modulation of the Ras/Raf/MAPKs pathway and play an essential role in NDDs. MAPKs include p38 MAPK, extracellular signal-regulated kinase 1/2 (ERK 1/2), and c-Jun N-terminal kinase (JNK), which are important molecular players in neurodegeneration. Ras/Raf, which is located the upstream of MAPK pathway influences the initiation and progression of neurodegeneration and is regulated by natural products.

PURPOSE

Thus, the present study aimed to investigate the neuroprotective roles of plant- and marine-derived secondary metabolites against several NDDs through the modulation of the Ras/Raf/MAPK signaling pathway.

STUDY DESIGN AND METHODS

A systematic and comprehensive review was performed to highlight the modulatory roles of natural products on the Ras/Raf/MAPK signaling pathway in NDDs, according to the PRISMA guideline, using scholarly electronic databases, including PubMed, Scopus, and Web of Sciences. Associated reference lists were also searched for the literature review.

RESULTS

From a total of 1495 results, finally 107 articles were included in the present study. The results show that several natural compounds such as alkaloid, phenolic, terpenoids, and nanoformulation were shown to have modulatory effects on the Ras/Raf/MAPKs pathway.

CONCLUSION

Natural products are promising multi-targeted agents with on NDDs through Ras/Raf/MAPKs pathway. Nevertheless, additional and complementary studies are necessary to check its efficacy and potential side effects.

Notoginsenoside R1 protects against myocardial ischemia/reperfusion injury in mice via suppressing TAK1-JNK/p38 signaling

Previous studies show that notoginsenoside R1 (NG-R1), a novel saponin isolated from Panax notoginseng, protects kidney, intestine, lung, brain and heart from ischemia-reperfusion injury. In this study we investigated the cardioprotective mechanisms of NG-R1 in myocardial ischemia/reperfusion (MI/R) injury in vivo and in vitro. MI/R injury was induced in mice by occluding the left anterior descending coronary artery for 30 min followed by 4 h reperfusion. The mice were treated with NG-R1 (25 mg/kg, i.p.) every 2 h for 3 times starting 30 min prior to ischemic surgery. We showed that NG-R1 administration significantly decreased the myocardial infarction area, alleviated myocardial cell damage and improved cardiac function in MI/R mice. In murine neonatal cardiomyocytes (CMs) subjected to hypoxia/reoxygenation (H/R) in vitro, pretreatment with NG-R1 (25 μM) significantly inhibited apoptosis. We revealed that NG-R1 suppressed the phosphorylation of transforming growth factor β-activated protein kinase 1 (TAK1), JNK and p38 in vivo and in vitro. Pretreatment with JNK agonist anisomycin or p38 agonist P79350 partially abolished the protective effects of NG-R1 in vivo and in vitro. Knockdown of TAK1 greatly ameliorated H/R-induced apoptosis of CMs, and NG-R1 pretreatment did not provide further protection in TAK1-silenced CMs under H/R injury. Overexpression of TAK1 abolished the anti-apoptotic effect of NG-R1 and diminished the inhibition of NG-R1 on JNK/p38 signaling in MI/R mice as well as in H/R-treated CMs. Collectively, NG-R1 alleviates MI/R injury by suppressing the activity of TAK1, subsequently inhibiting JNK/p38 signaling and attenuating cardiomyocyte apoptosis.

[Methylselenocysteine Promotes Etoposide Cytotoxicity by Enhancing Homotypic Gap Junctions Composed of Connexin 26]

Objective

To investigate the effect of methylselenocysteine (MSC) on the function of homotypic gap junction (GJ) composed of connexin (Cx) 26 and its regulation of chemotherapeutic drug cytotoxicity.

Methods

The Tet-on HeLa cells transfected with and stably expressing Cx26 were used as the tool cells. Effects of MSC on cell growth, GJ function, and Cx26 protein expression were examined by MTT method, parachute assay, and Western blot analysis, respectively. The cytotoxicity of chemotherapeutic drugs was determined by standard colony-forming assay, and the relationship between MSC's effect on cytotoxicity of these chemotherapeutic drugs and its regulation of GJ was further analyzed.

Results

In Tet-on HeLa cells, doxycycline (Dox) can induce the expression of Cx26, which could then form functional GJs. Within a concentration range of 50 μmol/L, MSC had no significant effect on HeLa cell growth. Non-toxic concentrations of MSC can enhance GJs in a concentration-dependent manner and exert its effect at the nanomolar level. This effect was associated with an induction of Cx26 protein expression by MSC. Among the three common chemotherapeutic agents with different mechanisms of action, etoposide (Eto) presented cytotoxicity differences between HeLa cells cultured at low density (nonconfluent, no GJ formed) and high density (confluent, GJ formed). What's more, the inhibitory effect of Eto combined with MSC on HeLa cell colony formation was stronger than that of Eto alone, and this effect occurred only in HeLa cells with GJ formation.

Conclusion

MSC can potentiate the cytotoxicity of Eto by enhancing the GJs composed of Cx26, indicating that combined strategy of selenide and chemotherapy shows potential value in the treatment of malignant tumors.

Shenmai Injection Attenuates Myocardial Ischemia/Reperfusion Injury by Targeting Nrf2/GPX4 Signalling-Mediated Ferroptosis

OBJECTIVE

To examine the effect of Shenmai Injection (SMJ) on ferroptosis during myocardial ischemia reperfusion (I/R) injury in rats and the underlying mechanism.

METHODS

A total of 120 SPF-grade adult male SD rats, weighing 220-250 g were randomly divided into different groups according to a random number table. Myocardial I/R model was established by occluding the left anterior descending artery for 30 min followed by 120 min of reperfusion. SMJ was injected intraperitoneally at the onset of 120 min of reperfusion, and erastin (an agonist of ferroptosis), ferrostatin-1 (Fer-1, an inhibitor of ferroptosis) and ML385 (an inhibitor of nuclear factor erythroid-2 related factor 2 (Nrf2)) were administered intraperitoneally separately 30 min before myocardial ischemia as different pretreatments. Cardiac function before ischemia, after ischemia and after reperfusion was analysed. Pathological changes in the myocardium and the ultrastructure of cardiomyocytes were observed, and the myocardial infarction area was measured. Additionally, the concentration of Fe2+ in heart tissues and the levels of creatine kinase-MB (CK-MB), troponin I (cTnl), malondialdehyde (MDA) and superoxide dismutase (SOD) in serum were measured using assay kits, and the expressions of Nrf2, glutathione peroxidase 4 (GPX4) and acyl-CoA synthetase long-chain family member 4 (ACSL4) were examined by Western blot.

RESULTS

Compared with the sham group, I/R significantly injured heart tissues, as evidenced by the disordered, ruptured and oedematous myocardial fibres; the increases in infarct size, serum CK-MB, cTnI and MDA levels, and myocardial Fe2+ concentrations; and the decreases in SOD activity (P<0.05). These results were accompanied by ultrastructural alterations to the mitochondria, increased expression of ACSL4 and inhibited the activation of Nrf2/GPX4 signalling (P<0.05). Compared with I/R group, pretreatment with 9 mL/kg SMJ and 2 mg/kg Fer-1 significantly reduced myocardial I/R injury, Fe2+ concentrations and ACSL4 expression and attenuated mitochondrial impairment, while 14 mg/kg erastin exacerbated myocardial I/R injury (P<0.05). In addition, cardioprotection provided by 9 mL/kg SMJ was completely reversed by ML385, as evidenced by the increased myocardial infarct size, CK-MB, cTnI, MDA and Fe2+ concentrations, and the decreased SOD activity (P<0.05).

CONCLUSIONS

Ferroptosis is involved in myocardial I/R injury. Pretreatment with SMJ alleviated myocardial I/R injury by activating Nrf2/GPX4 signalling-mediated ferroptosis, thereby providing a strategy for the prevention and treatment of ischemic heart diseases.

Pyroptosis and Intervertebral Disc Degeneration: Mechanistic Insights and Therapeutic Implications

Low back pain (LBP) is a common problem worldwide, resulting in great patient suffering and great challenges for the social health system. Intervertebral disc (IVD) degeneration (IVDD) is widely acknowledged as one of the key causes of LBP. Accumulating evidence suggests that aberrant pyroptosis of IVD cells is involved in the pathogenesis of IVDD progression, however, the comprehensive roles of pyroptosis in IVDD have not been fully established, leaving attempts to treat IVDD with anti-pyroptosis approaches questionable. In this review, we summarize the characteristics of pyroptosis and emphasize the effects of IVD cell pyroptosis on the pathological progression of IVDD, including secretion of cytokines, nucleus pulposus cell apoptosis and autophagy, accelerated extracellular matrix degradation, annulus fibrosus rupture, cartilage endplate calcification, vascularization, sensory and sympathetic fiber neoinnervation, and infiltrating lymphatic vessels. Finally, we discuss several interventions used to treat IVDD by targeting pyroptosis. This review provides novel insights into the crucial role of IVD cell pyroptosis in IVDD pathogenesis, and could be informative for developing novel therapeutic approaches for IVDD and LBP.

Case report: Treatment with Pien-Tze-Huang for prolonged positive SARS-CoV-2 test results in COVID-19 patients: A report of five cases

Coronavirus disease 2019 (COVID-19) has rapidly spread around the world since December 2019, becoming a global pandemic. Atypical cases of COVID-19, manifesting as prolonged positive SARS-CoV-2 test results during the convalescence period, have been encountered. These cases increase the difficulty of COVID-19 prevention and treatment. Here, we report five cases of COVID-19 patients who demonstrated prolonged positive SARS-CoV-2 tests after regular traditional Chinese medicine and western medicine treatments. After administration of Pien-Tze-Huang and cessation of previous treatments, SARS-CoV-2 tests results of the patients turned and remained negative. We believe the finding will contribute to a better understanding of atypical COVID-19 cases and hope to offer a potential therapy. Since this is a preliminary case series, larger-scale clinical trials are warranted.

Notoginsenoside R1-loaded mesoporous silica nanoparticles targeting the site of injury through inflammatory cells improves heart repair after myocardial infarction

Notoginsenoside R1 (NGR1) is the main monomeric component extracted from the dried roots and rhizomes of Panax notoginseng, and exerts pharmacological action against myocardial infarction (MI). Owing to the differences in compound distribution, absorption, and metabolism in vivo, exploring a more effective drug delivery system with a high therapeutic targeting effect is crucial. In the early stages of MI, CD11b-expressing monocytes and neutrophils accumulate at infarct sites. Thus, we designed a mesoporous silica nanoparticle-conjugated CD11b antibody with loaded NGR1 (MSN-NGR1-CD11b antibody), which allowed NGR1 precise targeted delivery to the heart in a noninvasively manner. By increasing targeting to the injured myocardium, intravenous injection of MSN-NGR1-CD11b antibody nanoparticle in MI mice improved cardiac function and angiogenesis, reduced cell apoptosis, and regulate macrophage phenotype and inflammatory factors and chemokines. In order to further explore the mechanism of NGR1 protecting myocardium, cell oxidative stress model and oxygen-glucose deprivation (OGD) model were established. NGR1 protected H9C2 cells and primary cardiomyocytes against oxidative injury induced by H₂O₂ and OGD treatment. Further network pharmacology and molecular docking analyses suggested that the AKT, MAPK and Hippo signaling pathways were involved in the regulation of NGR1 in myocardial protection. Indeed, NGR1 could elevate the levels of p-Akt and p-ERK, and promote the nuclear translocation of YAP. Furthermore, LY294002 (AKT inhibitor), U0126 (ERK1/2 inhibitor) and Verteporfin (YAP inhibitor) administration in H9C2 cells indicated the involvement of AKT, MAPK and Hippo signaling pathways in NGR1 effects. Meanwhile, MSN-NGR1-CD11b antibody nanoparticles enhanced the activation of AKT and MAPK signaling pathways and the nuclear translocation of YAP at the infarcted site. Our research demonstrated that MSN-NGR1-CD11b antibody nanoparticle injection after MI enhanced the targeting of NGR1 to the infarcted myocardium and improved cardiac function. More importantly, our pioneering research provides a new strategy for targeting drug delivery systems to the ischemic niche.

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CD11b antibody modification enhanced the target of Mesoporous silica nanoparticles to injured myocardium.

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NGR1 promoted the survival of H9C2 against oxidative stress injury through PIK3/AKT, MAPK/ERK and YAP signaling pathways.

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NGR1 protected neonatal and adult cardiomyocytes from H₂O₂ and OGD induced oxidative stress damage.

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MSN-NGR1-CD11b antibody nanoparticles improved heart function by activating PIK3/AKT, MAPK/ERK and YAP signaling pathways.

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MSN-NGR1-CD11b antibody nanoparticles induced M2 polarization of macrophages and regulated the inflammatory factors.

Notoginsenoside R1 Regulates Ischemic Myocardial Lipid Metabolism by Activating the AKT/mTOR Signaling Pathway

Ischemic heart diseases are responsible for more than one-third of all deaths worldwide. Radix notoginseng is widely used to treat ischemic heart disease in China and other Asian countries, and notoginsenoside R1 (NGR1) is its characteristic and large-amount ingredient. However, the potential molecular mechanisms of NGR1 in improving ischemic heart diseases are unclear. In this study, we combined pharmacological evaluation with network pharmacology, myocardial proteomics, and conventional molecular dynamics (MD) simulation to explore the cardio-protection mechanisms of NGR1. Our results revealed that NGR1 improved the echocardiographic, tissue pathological, and serum biochemical perturbations in myocardial ischemic rats. The network pharmacology studies indicated that NGR1 mainly regulated smooth muscle cell proliferation, vasculature development, and lipid metabolism signaling, especially in the PI3K/AKT pathway. Myocardial proteomics revealed that the function of NGR1 was focused on regulating metabolic and energy supply processes. The research combined reverse-docked targets with differential proteins and demonstrated that NGR1 modulated lipid metabolism in ischemic myocardia by interacting with mTOR and AKT. Conventional MD simulation was applied to investigate the influence of NGR1 on the structural stabilization of the mTOR and AKT complex. The results suggested that NGR1 can strengthen the affinity stabilization of mTOR and AKT. Our study first revealed that NGR1 enhanced the affinity stabilization of mTOR and AKT, thus promoting the activation of the AKT/mTOR pathway and improving lipid metabolic abnormity in myocardial ischemic rats.

Antidepressant Active Ingredients From Chinese Traditional Herb Panax Notoginseng: A Pharmacological Mechanism Review

Depression is one of the most common mental illnesses in the world and is highly disabling, lethal, and seriously endangers social stability. The side effects of clinical drugs used to treat depression are obvious, and the onset time is longer. Therefore, there is a great demand for antidepressant drugs with better curative effects, fewer side effects, and shorter onset time. Panax notoginseng, a Chinese herbal medication, has been used to treat depression for thousands of years and shown to have a therapeutic effect on depression. This review surveyed PubMed’s most recent 20 years of research on Panax notoginseng’s use for treating depression. We mainly highlight animal model research and outlined the pathways influenced by medicines. We provide a narrative review of recent empirical evidence of the anti-depressive effects of Panax Notoginseng and novel ideas for developing innovative clinical antidepressants with fewer side effects.

Notoginsenoside R1 Promotes Migration, Adhesin, Spreading, and Osteogenic Differentiation of Human Adipose Tissue-Derived Mesenchymal Stromal Cells

Cellular activities, such as attachment, spreading, proliferation, migration, and differentiation are indispensable for the success of bone tissue engineering. Mesenchymal stromal cells (MSCs) are the key precursor cells to regenerate bone. Bioactive compounds from natural products had shown bone regenerative potential. Notoginsenoside R1 (NGR1) is a primary bioactive natural compound that regulates various biological activities, including cardiovascular protection, neuro-protection, and anti-cancer effects. However, the effect of NGR1 on migration, adhesion, spreading, and osteogenic differentiation of MSCs required for bone tissue engineering application has not been tested properly. In this study, we aimed to analyze the effect of NGR1 on the cellular activities of MSCs. Since human adipose-derived stromal cells (hASCs) are commonly used MSCs for bone tissue engineering, we used hASCs as a model of MSCs. The optimal concentration of 0.05 μg/mL NGR1 was biocompatible and promoted migration and osteogenic differentiation of hASCs. Pro-angiogenic factor VEGF expression was upregulated in NGR1-treated hASCs. NGR1 enhanced the adhesion and spreading of hASCs on the bio-inert glass surface. NGR1 robustly promoted hASCs adhesion and survival in 3D-printed TCP scaffold both in vitro and in vivo. NGR1 mitigated LPS-induced expression of inflammatory markers IL-1β, IL-6, and TNF-α in hASCs as well as inhibited the RANKL/OPG expression ratio. In conclusion, the biocompatible NGR1 promoted the migration, adhesion, spreading, osteogenic differentiation, and anti-inflammatory properties of hASCs.

Notoginsenoside R1, An Active Compound from Panax notoginseng, Inhibits Hepatic Stellate Cell Activation and Liver Fibrosis via MAPK Signaling Pathway

Activation of the hepatic stellate cell is implicated in pathological vascularization during development of liver fibrosis. MAPK signaling is involved in the activation of hepatic stellate cell. Oxidative stress and inflammation are also involved in the pathogenesis of liver fibrosis. Notoginsenoside R1 is an effective saponin isolated from the roots of Panax notoginseng (Burk) F. H. Chen and exerts anti-oxidant, anti-inflammatory and anti-fibrotic roles in various diseases. However, the role of Notoginsenoside R1 in liver fibrosis has not been investigated yet. First, a rat model with liver fibrosis was established through oral gavage administration with carbon tetrachloride. Data from hematoxylin and eosin (H&E) and Masson's trichrome stainings showed that carbon tetrachloride induced severe hepatic damages, including inflammatory cell infiltration, lipid droplets deposition in hepatocytes and liver centrilobular necrosis. Meanwhile, the rats were also intraperitoneal injected with different concentrations of Notoginsenoside R1. Results demonstrated that Notoginsenoside R1 treatment suppressed the pathological changes in the livers with enhanced levels of ALB and TP, and reduced levels of ALP, AST and ALT. Second, Notoginsenoside R1 also significantly attenuated carbon tetrachloride-induced decrease in PPAR-[Formula: see text] and increase in Coll-a1, [Formula: see text]-SMA and TIMP1 in liver tissues ([Formula: see text][Formula: see text] 0.001). Third, the decrease in GSH, SOD and GST and increase in MDA, IL-1[Formula: see text], IL-6 and TNF-[Formula: see text] induced by carbon tetrachloride were markedly restored by Notoginsenoside R1 ([Formula: see text][Formula: see text] 0.001). Lastly, Notoginsenoside R1 counteracted with the promotive effects of carbon tetrachloride on levels of proteins involved in MAPK signaling, including phosphorylated p65 (p-p65), p-ERK, p-JNK and p-p38. In conclusion, Notoginsenoside R1 suppressed the activation of hepatic stellate cells and exerted anti- oxidant and anti-inflammatory to attenuate carbon tetrachloride-induced liver fibrosis through inactivation of NF-[Formula: see text]B and MAPK signaling.

Notoginsenoside R1 (NG-R1) Promoted Lymphatic Drainage Function to Ameliorating Rheumatoid Arthritis in TNF-Tg Mice by Suppressing NF-κB Signaling Pathway

Rheumatoid arthritis (RA) is a chronic autoimmune disease that is primarily characterized by synovial inflammation. Our previous studies demonstrated that the lymphatic system is critical for the development and maintenance of RA disease, and sufficient lymph drainage helps to improve joint inflammation. In this study, we found that NG-R1, the main active component in the traditional Chinese medicinal herb Sanchi, activating lymphatic function can attenuate synovial inflammation. According to histopathological staining of ankle sections, NG-R1 significantly decreased the area of inflammation and reduced bone destruction of ankle joints in TNF-Tg mice. Near infrared-indocyanine green (NIR-ICG) lymphatic imaging system has shown that NG-R1 significantly improved the lymphatic drainage function. However, the molecular mechanism of its activity is not properly understood. Our in-depth study demonstrates that NG-R1 reduced the inflammatory cytokine production of lymphatic endothelial cells (LECs) stimulated by TNF-α, and the mechanism ameliorated the phosphorylation of IKKα/β and p65, and the translocation of p65 into the nucleus. In summary, this study proved that NG-R1 promoted lymphatic drainage function to ameliorating rheumatoid arthritis in TNF-Tg mice by suppressing NF-κB signaling pathway.

Regulation of reactive oxygen species by phytochemicals for the management of cancer and diabetes

Cancer and diabetes mellitus are served as typical life-threatening diseases with common risk factors. Developing therapeutic measures in cancers and diabetes have aroused attention for a long time. However, the problems with conventional treatments are in challenge, including side effects, economic burdens, and patient compliance. It is essential to secure safe and efficient therapeutic methods to overcome these issues. As an alternative method, antioxidant and pro-oxidant properties of phytochemicals from edible plants have come to the fore. Phytochemicals are naturally occurring compounds, considered promising agent applicable in treatment of various diseases with beneficial effects. Either antioxidative or pro-oxidative activity of various phytochemicals were found to contribute to regulation of cell proliferation, differentiation, cell cycle arrest, and apoptosis, which can exert preventive and therapeutic effects against cancer and diabetes. In this article, the antioxidant or pro-oxidant effects and underlying mechanisms of flavonoids, alkaloids, and saponins in cancer or diabetic models demonstrated by the recent studies are summarized.

Natural ingredients from Chinese materia medica for pulmonary hypertension

Pulmonary hypertension (PH) is a severe pathophysiological condition characterized by pulmonary artery remodeling and continuous increases in pulmonary artery pressure, which may eventually develop to right heart failure and death. Although newly discovered and incredible treatment strategies in recent years have improved the prognosis of PH, limited types of effective and economical drugs for PH still makes it as a life-threatening disease. Some drugs from Chinese materia medica (CMM) have been traditionally applied in the treatment of lung diseases. Accumulating evidence suggests active pharmaceutical ingredients (APIs) derived from those medicines brings promising future for the prevention and treatment of PH. In this review, we summarized the pharmacological effects of APIs derived from CMM which are potent in treating PH, so as to provide new thoughts for initial drug discovery and identification of potential therapeutic strategies in alternative medicine for PH.

Notoginsenoside R1 attenuates oxidative stress-induced osteoblast dysfunction through JNK signalling pathway

Oxidative stress (OS)‐induced mitochondrial damage and the subsequent osteoblast dysfunction contributes to the initiation and progression of osteoporosis. Notoginsenoside R1 (NGR1), isolated from Panax notoginseng, has potent antioxidant effects and has been widely used in traditional Chinese medicine. This study aimed to investigate the protective property and mechanism of NGR1 on oxidative‐damaged osteoblast. Osteoblastic MC3T3‐E1 cells were pretreated with NGR1 24 h before hydrogen peroxide administration simulating OS attack. Cell viability, apoptosis rate, osteogenic activity and markers of mitochondrial function were examined. The role of C‐Jun N‐terminal kinase (JNK) signalling pathway on oxidative injured osteoblast and mitochondrial function was also detected. Our data indicate that NGR1 (25 μM) could reduce apoptosis as well as restore osteoblast viability and osteogenic differentiation. NGR1 also reduced OS‐induced mitochondrial ROS and restored mitochondrial membrane potential, adenosine triphosphate production and mitochondrial DNA copy number. NGR1 could block JNK pathway and antagonize the destructive effects of OS. JNK inhibitor (SP600125) mimicked the protective effects of NGR1while JNK agonist (Anisomycin) abolished it. These data indicated that NGR1 could significantly attenuate OS‐induced mitochondrial damage and restore osteogenic differentiation of osteoblast via suppressing JNK signalling pathway activation, thus becoming a promising agent in treating osteoporosis.

Panax notoginseng Saponin Promotes Bone Regeneration in Distraction Osteogenesis via the TGF-β1 Signaling Pathway

Distraction osteogenesis (DO) is an efficient strategy that is employed for the treatment of large bone defects in craniomaxillofacial surgery. Despite its utility, however, DO is associated with a prolonged consolidation phase and a high complication rate that hinder its more widespread utilization. Panax notoginseng saponin (PNS) is a traditional Chinese medicine that is frequently administered for the treatment of a range of conditions. Herein, we explored the ability of PNS treatment to influence osteogenic differentiation using both rabbit bone marrow mesenchymal cells (BMSCs) and a model of mandibular DO. BMSC proliferation was assessed via CCK-8 assay, while osteogenic differentiation was monitored through ALP and alizarin red S staining. A PCR approach was used to evaluate the expression of genes associated with osteogenesis (ALP, Runx2, and OCN) and genes linked to the TGF pathway (TβR-II, SMAD2, SMAD3, and PPM1A). For in vivo experiments, treated BMSCs were locally injected into the DO gap, with PNS being injected into treated rabbits every other day throughout the experimental period. The quality of the regenerative process was assessed via scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray imaging, and hematoxylin and eosin (H&E) staining. These analyses revealed that PNS was able to promote BMSC osteogenesis and mandibular generation, driving the upregulation of osteogenesis-related genes at the mRNA levels through the modulation of the TGF-β1/Smad pathway. Consistently, the overexpression or silencing of TβR-II in PNS-treated BMSCs was sufficient to modulate their osteogenic potential. Analyses of in vivo mandibular DO outcomes revealed significantly augmented new bone growth in the PNS-treated group relative to control animals, with maximal osteogenesis in the group overexpressing rabbit TβR-II. Together, these results highlight the PNS as a promising and cost-effective therapeutic tool with the potential to enhance bone regeneration in clinical contexts through the modulation of the TGF-β1/Smad pathway.

Regulation of the PTEN/PI3K/AKT pathway in RCC using the active compounds of natural products in vitro

Since Professor Tu Youyou won the 2015 Nobel Prize in Physiology and Medicine for the discovery of artemisinin, which is used to treat malaria, increased attention has been paid to the extracts obtained from plants, in order to analyze their biological activities, particularly with regard to their antitumor activity. Therefore, the present study explored the biochemical properties of seven natural plant extracts on renal cell carcinoma (RCC). 786-O and OS-RC-2 cells were cultured and treated with different concentrations of the extracts. Then, cell viability, the IC₅₀ value and proliferation was determined using a Cell Counting Kit-8 assay. Apoptosis and cell cycle distribution were evaluated via flow cytometry. The expression levels of proteins were assessed using western blotting, and cellular morphology was observed using a light microscope. The results showed that sophoricoside, aucubin, notoginsenoside R1 and ginsenoside Rg1 did not exhibit a cytotoxic effect on RCC cells, whereas ginsenoside Re and allicin exhibited a very slight inhibitory effect. Naringenin possessed the highest activity of the analyzed extracts. The IC₅₀ values of naringenin on 786-O and OS-RC-2 cells were 8.91±0.33 and 7.78±2.65 µM, respectively. In addition, naringenin notably inhibited the proliferation of RCC cells by decreasing Ki67 expression, blocked cell cycle progression in the G₂ phase by regulating expression of cell cycle proteins, and increased apoptosis by upregulating caspase-8 expression, downregulating Bcl-2 expression and altering the cellular morphology. Furthermore, naringenin inhibited cell proliferation and promoted apoptosis by upregulating the expression of PTEN at the protein level, downregulated the expression of PI3K and phosphorylated-(p-)AKT, but did not affect the expression of AKT, mTOR or p-mTOR. The seven plant extracts analyzed showed differing degrees of anti-RCC activity. Sophoricoside, aucubin, notoginsenoside R1 and ginsenoside Rg1 did not exhibit notable anti-RCC activity, whereas the effect of ginsenoside Re and allicin on RCC was considerably weak. However, naringenin showed potent anti-proliferative, apoptosis inducing and cell cycle arresting activity on RCC cells via regulation of the PTEN/PI3K/AKT signaling pathway.

Phytochemicals: Targeting Mitophagy to Treat Metabolic Disorders

Metabolic disorders include metabolic syndrome, obesity, type 2 diabetes mellitus, non-alcoholic fatty liver disease and cardiovascular diseases. Due to unhealthy lifestyles such as high-calorie diet, sedentary and physical inactivity, the prevalence of metabolic disorders poses a huge challenge to global human health, which is the leading cause of global human death. Mitochondrion is the major site of adenosine triphosphate synthesis, fatty acid β-oxidation and ROS production. Accumulating evidence suggests that mitochondrial dysfunction-related oxidative stress and inflammation is involved in the development of metabolic disorders. Mitophagy, a catabolic process, selectively degrades damaged or superfluous mitochondria to reverse mitochondrial dysfunction and preserve mitochondrial function. It is considered to be one of the major mechanisms responsible for mitochondrial quality control. Growing evidence shows that mitophagy can prevent and treat metabolic disorders through suppressing mitochondrial dysfunction-induced oxidative stress and inflammation. In the past decade, in order to expand the range of pharmaceutical options, more and more phytochemicals have been proven to have therapeutic effects on metabolic disorders. Many of these phytochemicals have been proved to activate mitophagy to ameliorate metabolic disorders. Given the ongoing epidemic of metabolic disorders, it is of great significance to explore the contribution and underlying mechanisms of mitophagy in metabolic disorders, and to understand the effects and molecular mechanisms of phytochemicals on the treatment of metabolic disorders. Here, we investigate the mechanism of mitochondrial dysfunction in metabolic disorders and discuss the potential of targeting mitophagy with phytochemicals for the treatment of metabolic disorders, with a view to providing a direction for finding phytochemicals that target mitophagy to prevent or treat metabolic disorders.

Notoginsenoside R1 protects hypoxia-reoxygenation deprivation-induced injury by upregulation of miR-132 in H9c2 cells

BACKGROUND

Myocardial ischemia/reperfusion injury (IRI) is a common perioperative complication of heart and great vessels surgery, aggravating the original myocardial damage and seriously affecting the postoperative recovery of cardiac function. The aim of this study was to reveal the functional effects and potential mechanisms of notoginsenoside R1 (NG-R1) in myocardial cells injured by hypoxia-reoxygenation (H/R).

METHODS

The rat cardiomyocyte line H9c2 was subjected to H/R with or without NG-R1 treatment. The levels of miR-132 and HBEGF in the cell were altered by microRNA or short-hairpin RNA transfection. Cell viability, apoptosis, lactate dehydrogenase (LDH) and malondialdehyde (MDA) were monitored. Dual luciferin was used to detect the relationship between miR-132 and HBEGF.

RESULTS

NG-R1 (20 μM) had no impact on H9c2 cells, but cell viability was significantly reduced at 80 μM. NG-R1 (20 μM) protected H9c2 cells against H/R-induced cell damage, accompanied by increased cell viability, reduced cell apoptosis, and downregulation of LDH and MDA. Furthermore, the level of miR-132 was decreased in response to H/R exposure but then increased after NG-R1 treatment. When miR-132 was overexpressed, H/R-induced cell damage could be recovered. Downregulation of miR-132 limited the protective effect of NG-R1 on H/R damage. We also found that HBEGF was a direct target of miR-132. The expression of HBEGF was increased upon H/R damage, and this increase was reversed after NG-R1 treatment.

CONCLUSIONS

This study demonstrated that NG-R1 markedly protected H9c2 cells against H/R-induced damage via upregulation of miR-132 and downregulation of its target protein HBEGF.

Protective effects of notoginsenoside R1 on acute lung injury in rats with sepsis

Background

To clarify the mechanism of notoginsenoside R1 in the treatment of septic acute lung injury (ALI) based on network pharmacological analysis, and to verify it in the model of septic ALI in rats.

Methods

Based on database searching, the related targets of notoginsenoside R1 and ALI were identified, and the component-disease-target network was constructed. The core targets were screened by protein-protein interaction (PPI), and the functional enrichment of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) was analyzed. The rat model of septic ALI was further established to investigate the pharmacological effects of notoginsenoside R1.

Results

Notoginsenoside R1 possibly affected ALI through 150 targets, of which 36 were core targets. GO semantic similarity analysis showed that notoginsenoside R1 might play a role in regulating interleukin 17 (IL-17) signal pathway, tumor necrosis factor (TNF) signal pathway and other key links by regulating MAPK1, MAPK3, IL-1β and other targets. The results of pharmacological experiments showed that notoginsenoside R1 could significantly reduce the wet:dry ratio of the lung in an animal model of ALI, improve the pathological injury of the lung, and reduce the content of IL-1β in serum and in bronchoalveolar lavage fluid (BALF) of experimental animals.

Conclusions

Notoginsenoside R1 can inhibit pulmonary edema, reduce inflammation, and improve lung lesions through multiple targets and pathways to achieve the pharmacological effects in the treatment of septic ALI.

Notoginsenoside R1 alleviates TEGDMA-induced mitochondrial apoptosis in preodontoblasts through activation of Akt/Nrf2 pathway-dependent mitophagy

Incomplete polymerization or biodegradation of dental resin materials results in the release of resin monomers such as triethylene glycol dimethacrylate (TEGDMA), causing severe injury of dental pulp cells. To date, there has been no efficient treatment option for this complication, in part due to the lack of understanding of the mechanism underlying these phenomena. Here, for the first time, we found that notoginsenoside R1 (NR1), a bioactive ingredient extracted from Panax notoginseng, exerted an obvious protective effect on TEGDMA-induced mitochondrial apoptosis in the preodontoblast mDPC6T cell line. In terms of the mechanism of action, NR1 enhanced the level of phosphorylated Akt (protein kinase B), resulting in the activation of a transcriptional factor, nuclear factor erythroid 2-related factor 2 (Nrf2), and eventually upregulating cellular ability to resist TEGDMA-related toxicity. Inhibiting the Akt/Nrf2 pathway by pharmaceutical inhibitors significantly decreased NR1-mediated cellular antioxidant properties and aggravated mitochondrial oxidative damage in TEGDMA-treated cells. Interestingly, NR1 also promoted mitophagy, which was identified as the potential downstream of the Akt/Nrf2 pathway. Blocking the Akt/Nrf2 pathway inhibited mitophagy and abolished the protection of NR1 on cells exposed to TEGDMA. In conclusion, these findings reveal that the activation of Akt/Nrf2 pathway-mediated mitophagy by NR1 might be a promising approach for preventing resin monomer-induced dental pulp injury.

HAGLR aggravates neuropathic pain and promotes inflammatory response and apoptosis of lipopolysaccharide-treated SH-SY5Y cells by sequestering miR-182-5p from ATAT1 and activating NLRP3 inflammasome

BACKGROUND

Chronic neuropathic pain is characterized by neuroinflammation. Previously, long noncoding RNA (lncRNA) HAGLR was reported to regulate the inflammatory response of SH-SY5Y cells. However, neither the specific function nor the potential mechanism of HAGLR in neuropathic pain has been explored.

AIM OF THE STUDY

Our study is aimed to figure out the role of HAGLR in neuropathic pain.

METHODS

SH-SY5Y cells were treated with lipopolysaccharide (LPS) to mimic neuron injury in vitro. The chronic constriction injury (CCI) rat models were established by ligation of sciatic nerve to mimic neuropathic pain in vivo. Behavioral assessment assays were performed to determine the effects of HAGLR on hypersensitivity in neuropathic pain. Enzyme-linked immunosorbent assay kits were used for detection of inflammatory cytokines. Flow cytometry analysis and Western blot were applied to detect apoptosis.

RESULTS

HAGLR displayed high levels in spinal cords of CCI rats and in LPS treated SH-SY5Y cells. Knockdown of HAGLR inhibited inflammation and neuron apoptosis of LPS treated SH-SY5Y cells. Mechanistically, HAGLR bound with miR-182-5p in SH-SY5Y cells. ATAT1 served as a target of miR-182-5p. HAGLR activated the NLRP3 inflammasome by ATAT1. Rescue assays demonstrated that overexpression of ATAT1 or NLRP3 reversed the suppressive effects of HAGLR silencing on apoptosis and inflammatory response in SH-SY5Y cells and in spinal cords of CCI rats. The inhibitory effects of silenced HAGLR on hypersensitivity in neuropathic pain were also rescued by ATAT1 or NLRP3.

CONCLUSIONS

HAGLR aggravates neuropathic pain by sequestering miR-182-5p from ATAT1 and activating NLRP3 inflammasome, which may provide a potential therapeutic target for neuropathic pain treatment.

WITHDRAWN: MiR-216b-5p attenuates chronic constriction injury-induced neuropathic pain in female rats by targeting MAL2 and inactivating Wnt/β-catenin signaling pathway

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Notoginsenoside R1 counteracts mesenchymal stem cell-evoked oncogenesis and doxorubicin resistance in osteosarcoma cells by blocking IL-6 secretion-induced JAK2/STAT3 signaling

Tumor microenvironment is a critical participant in the initiation, progression and drug resistance of carcinomas, including osteosarcoma. Notoginsenoside R1 (NGR1) is a proverbial active ingredient of the traditional Chinese medicine Panax notoginseng (PN) and possess undeniable roles in several cancers. Nevertheless, its function in osteosarcoma and tumor microenvironment remains elusive. In the current study, exposure to NGR1 dose-dependently inhibited osteosarcoma cell viability and migration, and induced apoptosis. Furthermore, osteosarcoma cells that were incubated with conditioned medium (CM) from bone marrow mesenchymal stem cells (BMSCs) exhibited greater proliferation, migration capacity and MMP-2 and MMP-9 expression relative to control cells, which was reversed when BMSCs were treated with NGR1. Notably, administration with NGR1 antagonized CM-evoked doxorubicin resistance in osteosarcoma cells by decreasing cell viability and increasing cell apoptosis and caspase-3/9 activity. Mechanically, NGR1 suppressed IL-6 secretion from BMSCs, as well as the subsequent activation of the JAK2/STAT3 signaling in osteosarcoma cells. In addition, blocking the JAK2 pathway by its antagonist AG490 reversed CM-induced osteosarcoma cell proliferation, migration and doxorubicin resistance. Moreover, exogenous supplementation with IL-6 engendered not only the reactivation of the JAK2/STAT3 signaling but also muted NGR1-mediated efficacy against osteosarcoma cell malignancy and doxorubicin resistance. Collectively, NGR1 may directly restrain osteosarcoma cell growth and migration, or indirectly antagonize MSC-evoked malignancy and drug resistance by interdicting IL-6 secretion-evoked activation of the JAK2/STAT3 pathway. Consequently, the current study may highlight a promising therapeutic strategy against osteosarcoma by regulating tumor cells and the tumor microenvironment.

Long noncoding RNA MEG3 contributes to dysfunction of brain microvascular endothelial cells after intracerebral hemorrhage by regulating the miR-1930-5p/Mllt1 axis

BACKGROUND

Intracerebral hemorrhage (ICH) is a subtype of stroke and causes disability and death worldwide. The roles of long noncoding RNAs (lncRNAs) in brain function and neurological diseases have been revealed. LncRNA maternally expressed gene 3 (MEG3) is involved in neurological impairment, but its role in ICH remains unknown.

AIMS

The aim of this research is to explore the role of MEG3 in ICH.

METHODS AND RESULTS

Here, we established an ICH mouse model via intracerebral injection of autologous blood. Primary brain microvascular endothelial cells (BMECs) were treated with oxygen-and-glucose-deprivation (OGD) plus hemin to establish the model in vitro. We observed that MEG3 expression was significantly upregulated in both ICH mouse model and OGD/hemin (OGD/H) induced BMECs. The downregulation of MEG3 suppressed cell apoptosis and the activation of NOD-like receptor family protein 3 (NLRP3) inflammasome in OGD/H-induced BMECs. In ICH mice, MEG3 downregulation inhibited cell apoptosis and improved brain dysfunction. Mechanistically, MEG3 was confirmed to act as a molecular sponge for microRNA (miR)-1930-5p, and Mllt1 was a downstream target for miR-1930-5p. MEG3 competitively bound with miR-1930-5p to upregulate Mllt1. We further verified that Mllt1 overexpression reversed the inhibitory effect of miR-1930-5p in OGD/H-induced BMECs.

CONCLUSIONS

In conclusion, lncRNA MEG3 promoted the dysfunction of BMECs by modulating the miR-1930-5p/Mllt1 axis, which provides a potential target in gene therapy for brain injury following ICH.

Huoxue Huatan Decoction Ameliorates Myocardial Ischemia/Reperfusion Injury in Hyperlipidemic Rats via PGC-1α-PPARα and PGC-1α-NRF1-mtTFA Pathways

Objective

The aim of this study was to eluc\idate the preventive and therapeutic effects and the underlying mechanisms of Huoxue Huatan Decoction (HXHT) on myocardial ischemia/reperfusion (I/R) injury in hyperlipidemic rats.

Methods

An I/R model was established in hyperlipidemic Wistar rats. After 4–8 weeks of HXHT treatment, the physical signs of rats were observed. Lipid metabolism, myocardial enzyme spectrum, cardiac function, myocardial histomorphology, and mitochondrial biosynthesis were investigated by a biochemical method, ultrasonography, electron microscopy, pathological examination, real-time PCR, and Western blot.

Results

HXHT can affect lipid metabolism at different time points and significantly reduce the levels of cholesterol (CHO), triglyceride (TG), high-density lipid-cholesterol (HDL-C), and low-density lipid-cholesterol (LDL-C) in hyperlipidemic rats (P < 0.05 or P < 0.01); it can significantly reduce the levels of creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH), reduce the myocardial infarct size and myocardial ischemic area, and improve cardiac function. The results of myocardial histomorphology showed that HXHT could protect myocardial cells, relieve swelling, reduce the number of cardiac lipid droplets, and improve myocardial mitochondrial function. HXHT could significantly increase the levels of total superoxide dismutase (T-SOD) and succinate dehydrogenase (SDH) (P < 0.05 or P < 0.01), increase CuZn-superoxide dismutase (CuZn-SOD) and glutathione-peroxidase (GSH-Px) levels, and decrease the levels of malondialdehyde (MDA) (P < 0.05); it could increase the mRNA and protein expression levels of peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC-1α), peroxisome proliferator-activated receptor alpha (PPARα), nuclear respiratory factor 1 (NRF1), and mitochondrial transcription factor A (mtTFA) (P < 0.05 or P < 0.01), and increase the synthesis of mitochondrial DNA (mtDNA) (P < 0.01).

Conclusion

HXHT can reduce myocardial I/R injury in hyperlipidemic rats. The protective mechanisms may involve a reduction in blood lipids, enhancement of PGC-1α–PPARα pathway activity, and, subsequently, an increase in fatty acid β-oxidation, which may provide the required input for mitochondrial energy metabolism. HXHT can additionally enhance PGC-1α–NRF1–mtTFA pathway activity and, subsequently, increase the antioxidant capacity, promote mtDNA synthesis, and reduce mitochondrial damage. The two pathways use PGC-1α as the intersection point to protect mitochondrial structure and function, reduce I/R-induced injury, and improve cardiac function.

Efficacy and safety of high-dose Xueshuantong injection (lyophilised) in reducing the incidence of major adverse cardiovascular events in patients with unstable angina: a protocol of a randomised, parallel-arm, controlled, double-blind and multicentre clinical trial based on dual antiplatelet therapy

INTRODUCTION

Unstable angina (UA), referred to as acute coronary syndrome (ACS), causes unexpected chest pain. Xueshuantong injection (lyophilised) (XST) is a traditional Chinese herbal injection having the potential to treat ACS. However, no clinical trial has been performed in this field. This clinical trial aims to examine the efficacy and safety of XST.

METHODS AND ANALYSIS

This is a randomised, parallel-arm, controlled, double-blind and multicentre clinical trial. A total of 1200 participants with UA will be enrolled in a 1:1 ratio, with 600 patients included in the XST treatment group and 600 with 1/20th dose in the control group. The efficacy assessment and major adverse cardiovascular events will be observed, and the frequency of angina attack, angina pectoris will be examined at the start and end of the run-in period. All adverse events will be recorded, regardless of the severity, to assess the safety of XST. The baseline characteristics of patients will be summarised and compared using the t test or non-parametric statistical test. Qualitative data will be analysed using the χ² or Fisher exact tests, Cochran-Mantel-Hasenszel test and Wilcoxon test.

ETHICS AND DISSEMINATION

This trial has been approved by the Research Ethics Committee of The First Affiliated Hospital of Guangzhou University of Chinese Medicine, China (approval number: ZYYEC [2017] 0021). Written informed consent will be obtained from all participants. The results of this trial will be disseminated to the public through academic conferences and peer-reviewed journals.

TRIAL REGISTRATION

This study was registered on the Chinese Clinical Trial Registry (http://www.chictr.org.cn/) with the ID ChiCTR1800015911.