Corynoline Exhibits Anti-inflammatory Effects in Lipopolysaccharide (LPS)-Stimulated Human Umbilical Vein Endothelial Cells through Activating Nrf2

Corynoline inhibits esophageal squamous cell carcinoma growth via targeting Pim-3

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is an aggressive and deadly malignancy characterized by late-stage diagnosis, therapy resistance, and a poor 5-year survival rate. Finding novel therapeutic targets and their inhibitors for ESCC prevention and therapy is urgently needed.

METHODS

We investigated the proviral integration site for maloney murine leukemia virus 3 (Pim-3) protein levels using immunohistochemistry. Using Methyl Thiazolyl Tetrazolium and clone formation assay, we verified the function of Pim-3 in cell proliferation. The binding and inhibition of Pim-3 by corynoline were verified by computer docking, pull-down assay, cellular thermal shift assay, and kinase assay. Cell proliferation, Western blot, and a patient-derived xenograft tumor model were performed to elucidate the mechanism of corynoline inhibiting ESCC growth.

RESULTS

Pim-3 was highly expressed in ESCC and played an oncogenic role. The augmentation of Pim-3 enhanced cell proliferation and tumor development by phosphorylating mitogen-activated protein kinase 1 (MAPK1) at T185 and Y187. The deletion of Pim-3 induced apoptosis with upregulated cleaved caspase-9 and lower Bcl2 associated agonist of cell death (BAD) phosphorylation at S112. Additionally, binding assays demonstrated corynoline directly bound with Pim-3, inhibiting its activity, and suppressing ESCC growth.

CONCLUSIONS

Our findings suggest that Pim-3 promotes ESCC progression. Corynoline inhibits ESCC progression through targeting Pim-3.

Q-switched Nd:YAG laser protects human keratinocytes from oxidative stress and inflammation via AhR-Nrf2 pathway

In recent years, some treatments for esthetic and pathologic skin conditions have increasingly been based on the use of non-ablative neodymium-doped yttrium aluminum garnet (Nd:YAG) laser due to its greater penetration ability than other types of lasers, few contraindications, minimal side effects, no damage for epidermidis and the rapid recovery of the treated patients. The skin is frequently exposed to many stressors such as radiation, toxic substances, metabolites, foods, mechanical insults, and allergen exposition that cause oxidative damage and have a decisive influence on the aging process. The imbalance between reactive oxygen species, reactive nitrogen species, and the malfunctioning of the antioxidant defense system promotes the establishment of an excessive inflammatory process, which can induce various diseases including cancer and neurodegenerative disorders. The present study investigated the cytoprotective function of Q-switched Nd:YAG laser against stress aging and cell injury in HaCaT cells. We evaluated the effect of the laser on antioxidant defenses, inflammation, metalloproteinases' expression, and the AhR-Nrf2 pathway. Q-switched Nd:YAG is able to upregulate the AhR pathway and the expression of IL-6 and TGF-β, which are involved in wound repair process, and to downregulate the expression of MMP-2 and 9, so preventing the collagen degradation. Q-switched Nd:YAG can stimulate the cellular antioxidant defenses by activating the AhR-Nrf2 system.

Brevilin A attenuates cartilage destruction in osteoarthritis mouse model by inhibiting inflammation and ferroptosis via SIRT1/Nrf2/GPX4 signaling pathway

Osteoarthritis (OA) is a serious orthopedic disease that affects people's quality of life. Although there are many treatment methods, the treatment effect is still not good. Brevilin A is a bioactive compound isolated from the medicinal herbCentipeda minima. The potential efficacy of brevilin A on OA was explored in this study. Mouse chondrocytes were isolated and stimulated by IL-1β and mouse OA model was induced by destabilization of the medial meniscus (DMM). The results demonstrated that brevilin A markedly inhibited IL-1β-induced MMP1 and MMP3 production. IL-1β-induced PGE2, NO, MDA, and iron production were alleviated by brevilin A. The production of GSH and the expression of SIRT1, Nrf2, HO-1, GPX4, and Ferritin were increased by brevilin A. Furthermore, the inhibition of brevilin A on IL-1β-induced inflammation and ferroptosis were prevented by SIRT1 inhibitor. In vivo, the results showed brevilin A markedly attenuated OA progression in DMM-induced mouse OA model. Also, brevilin A could alleviate MMP1, MMP3, iNOS, and COX2 expression in OA mice. In conclusion, brevilin A protected mice against OA via suppressing inflammatory response and ferroptosis by regulating SIRT1/Nrf2/GPX4 signaling.

Alkaloids as Natural NRF2 Inhibitors: Chemoprevention and Cytotoxic Action in Cancer

Being a controller of cytoprotective actions, inflammation, and mitochondrial function through participating in the regulation of multiple genes in response to stress-inducing endogenous or exogenous stressors, the transcription factor Nuclear Factor Erythroid 2-Related Factor 2 (NRF2) is considered the main cellular defense mechanism to maintain redox balance at cellular and tissue level. While a transient activation of NRF2 protects normal cells under oxidative stress, the hyperactivation of NRF2 in cancer cells may help them to survive and to adapt under oxidative stress. This can be detrimental and related to cancer progression and chemotherapy resistance. Therefore, inhibition of NRF2 activity may be an effective approach for sensitizing cancer cells to anticancer therapy. In this review, we examine alkaloids as NRF2 inhibitors from natural origin, their effects on cancer therapy, and/or as sensitizers of cancer cells to anticancer chemotherapeutics, and their potential clinical applications. Alkaloids, as inhibitor of the NRF2/KEAP1 signaling pathway, can have direct (berberine, evodiamine, and diterpenic aconitine types of alkaloids) or indirect (trigonelline) therapeutic/preventive effects. The network linking alkaloid action with oxidative stress and NRF2 modulation may result in an increased NRF2 synthesis, nuclear translocation, as well in a downstream impact on the synthesis of endogenous antioxidants, effects strongly presumed to be the mechanism of action of alkaloids in inducing cancer cell death or promoting sensitivity of cancer cells to chemotherapeutic agents. In this regard, the identification of additional alkaloids targeting the NRF2 pathway is desirable and the information arising from clinical trials will reveal the potential of these compounds as a promising target for anticancer therapy.

Corynoline ameliorates dextran sulfate sodium-induced colitis in mice by modulating Nrf2/NF-κB pathway

OBJECTIVE

Corynoline is an active substance extracted from Corydalis bungeana Turcz and exerts a therapeutic effect in multiple diseases by alleviating inflammatory response. The present study sought to elucidate the role of corynoline in ulcerative colitis (UC).

METHODS

The experimental colitis models were induced in BALB/c mice via receiving a drinking water supplemented with 3.5% (I) dextran sulfate sodium (DSS) ad libitum for 7 days.

RESULTS

Corynoline administration inhibited body weight loss, colon shortening, disease activity index and colonic pathomorphological changes in DSS-treated mice. Besides, corynoline down-regulated the levels of pro-inflammatory interleukin (IL)-1β, IL-6 and tumor necrosis factor Alpha (TNF-α), as well as decreased myeloperoxidase (MPO) activity in the colon of DSS-treated mice. In addition, severe oxidative stress in the colonic tissues of DSS-treated was mitigated by corynoline treatment. However, these beneficial effects were reversed by a specific nuclear factor E2-related factor 2 (Nrf2) inhibitor ML385 intervention. Further evidence confirmed that corynoline promoted Nrf2 nuclear migration and heme oxygenase-1 gene expression in the colonic tissues of UC mice. Besides, corynoline treatment restrained colonic nuclear factor-kappa B (NF-κB) activation as proved by the decrease in phosphorylation and nuclear translocation of NF-κB.

CONCLUSIONS

Corynoline ameliorates DSS-induced mouse colitis, which may provide a promising therapeutic strategy for UC treatment.

Targeted activation of Nrf2/ HO ‐1 pathway by Corynoline alleviates osteoporosis development

Oxidative stress is preferentially treated as a risk factor for the development and progression of osteoporosis. Corynoline as a component of Corydalis bungeana Turcz presents antioxidative and anti-inflammatory properties. In the present study, the effects of Corynoline on osteoblasts following hydrogen peroxide (H₂O₂)-induced injury were evaluated accompanied by the investigation of the molecular mechanisms involved. It was found that Corynoline downregulated the intracellular reactive oxygen species (ROS) generation and restored the osteogenic potential of the disrupted osteoblasts by H₂O₂ exposure. Furthermore, Corynoline was revealed to activate the Nrf2/HO-1 signaling pathway, while ML385 (an Nrf2 inhibitor) would prevent the Corynoline-mediated positive effects on the disrupted osteoblasts. In terms of the animal experiments, Corynoline treatment contributed to a significantly alleviated bone loss. These findings indicate that Corynoline may significantly attenuate the H₂O₂-induced oxidative damage of osteoblasts via the Nrf2/HO-1 signaling pathway, providing novel insights to the development of treatments for osteoporosis induced by oxidative injury.

Corynoline protects against zearalenone-induced liver injury by activating the SIRT1/Nrf2 signaling pathway

Corynoline has been reported to have anti-inflammatory and antioxidative effects. In the present study, the potential protective effects of corynoline against zearalenone (ZEA)-induced liver injury were investigated. ZEA was administered daily for 5 days. Then, liver tissues were used for subsequent experiments. Corynoline attenuated liver histopathological changes induced by ZEA. The production of tumor necrosis factor-α and interleukin-1β in liver tissues, as well as aspartate aminotransferase and alanine aminotransferase in serum, was also inhibited by corynoline. Meanwhile, ZEA-induced MPO activity and MDA content were both attenuated by corynoline. ZEA-induced NF-κB p65 and IκBα phosphorylation were inhibited by corynoline. Furthermore, SIRT1, Nrf2, and HO-1 expression were increased by corynoline. In addition, the protective effects of corynoline against liver injury were reversed by the SIRT1 inhibitor EX-527. Taken together, corynoline protected against ZEA-induced liver injury by activating the SIRT1/Nrf2 signaling pathway.

Corynoline Alleviates Osteoarthritis Development via the Nrf2/NF-κB Pathway

Purpose

OA is a multifactorial joint disease in which inflammation plays a substantial role in the destruction of joints. Corynoline (COR), a component of Corydalis bungeana Turcz., has anti-inflammatory effects.

Materials and Methods

We evaluated the significance and potential mechanisms of COR in OA development. The viabilities of chondrocytic cells upon COR exposure were assessed by CCK-8 assays. Western blot, qPCR, and ELISA were used to assess extracellular matrix (ECM) degeneration and inflammation. The NF-κB pathway was evaluated by western blot and immunofluorescence (IF). Prediction of the interacting proteins of COR was done by molecular docking, while Nrf2 knockdown by siRNAs was performed to ascertain its significance. Micro-CT, H&E, Safranin O-Fast Green (S-O), toluidine blue staining, and immunohistochemical examination were conducted to assess the therapeutic effects of COR on OA in destabilization of medial meniscus (DMM) models.

Results

COR inhibited ECM degeneration and proinflammatory factor levels and modulated the NF-κB pathway in IL-1β-treated chondrocytes. Mechanistically, COR bound Nrf2 to downregulate the NF-κB pathway. Moreover, COR ameliorated the OA process in DMM models.

Conclusion

We suggest that COR ameliorates OA progress through the Nrf2/NF-κB axis, indicating COR may have a therapeutic potential for OA.

Corybungines A-K: Isoquinoline alkaloids from Corydalis bungeana with dopamine D2 receptor activity

Eleven undescribed isoquinoline alkaloids corybungines A-K including a protoberberine-type alkaloid, an isoquinoline alkaloid with a unique 6-norprotoberberine skeleton, one 13,14-seco-protoberberine-type alkaloid, two 1a,14-seco-protoberberine-type alkaloids with a 4-(hydroxymethyl)phenoxy moiety and six aporphine alkaloids, together with seven known alkaloids, have been isolated from the whole herb extract of Corydalis bungeana Turcz. Their structures and absolute configurations were elucidated based on an analysis of spectroscopic data and electronic circular dichroism (ECD) spectra. (R)-stephanine displayed high antagonistic activity against the dopamine D2 receptor with an IC₅₀ value of 0.85 ± 0.09 μM in CHO-D2 cells. Additionally, corybungines D, F, H, (R)-roemerine, (R)-vireakine and (R)-tuduranine showed moderate D2 antagonism (IC₅₀ 5.20-26.07 μM). The preliminary structure-activity relationships (SARs) of aporphine alkaloids were discussed.

Corynoline protects ang II-induced hypertensive heart failure by increasing PPARα and Inhibiting NF-κB pathway

Heart failure is a fairly common outcome of hypertension. Recent studies have highlighted the key role of the non-hemodynamic activity of angiotensin II (Ang II) in hypertensive heart failure via inducing cardiac inflammation. Drugs that disrupt Ang II-induced cardiac inflammation may have clinical utility in the treatment of hypertensive heart failure. A naturally occurring compound, corynoline, exhibit anti-inflammatory activities in other systems. C57BL/6 mice were injected with Ang II via a micro-osmotic pump for four weeks to develop hypertensive heart failure. The mice were treated with corynoline by gavage for two weeks. RNA-sequencing analysis was performed to explore the potential mechanism of corynoline. We found that corynoline could inhibit inflammation, myocardial fibrosis, and hypertrophy to prevent heart dysfunction, without the alteration of blood pressure. RNA-sequencing analysis indicates that the PPARα pathway is involved Ang II-induced cardiac fibrosis and cardiac remodeling. Corynoline reversed Ang II-induced PPARα inhibition both in vitro and in vivo. We further found that corynoline increases the interaction between PPARα and P65 to inhibit the NF-κB pro-inflammatory pathway in H9c2 cells. Our studies show that corynoline relieves Ang II-induced hypertensive heart failure by increasing the interaction between PPARα and P65 to inhibit the NF-κB pathway.

Preparation of Rosin-Based Composite Membranes and Study of Their Dencichine Adsorption Properties

In this work, rosin-based composite membranes (RCMs) were developed as selective sorbents for the preparation of dencichine for the first time. The rosin-based polymer microspheres (RPMs) were synthesized using 4-ethylpyridine as a functional monomer and ethylene glycol maleic rosinate acrylate as a crosslinking. RCMs were prepared by spinning the RPMs onto the membranes by electrostatic spinning technology. The optimization of various parameters that affect RCMs was carried out, such as the ratio concentration and voltage intensity of electrospinning membrane. The RCMs were characterized by SEM, TGA and FT-IR. The performances of RCMs were assessed, which included adsorption isotherms, selective recognition and adsorption kinetics. The adsorption of dencichine on RCMs followed pseudo-second-order and adapted Langmuir–Freundlich isotherm model. As for the RCMs, the fast adsorption stage appeared within the first 45 min, and the experimental maximum adsorption capacity was 1.056 mg/g, which is much higher than the previous dencichine adsorbents reported in the literature. The initial decomposition temperature of RCMs is 297 °C, the tensile strength is 2.15 MPa and the elongation at break is 215.1%. The RCMs have good thermal stability and mechanical properties. These results indicated that RCMs are a tremendously promising adsorbent for enriching and purifying dencichine from the notoginseng extracts.

Antinociceptive and Anti-inflammatory Effect of Corynoline in Different Nociceptive and Inflammatory Experimental Models

Pain is growing to be a massive health issue across the globe. It is reported that one in every five adults tends to suffer from pain worldwide each year, regardless of age and gender. Inflammation caused by tissue damage, chemical stimulus, and foreign substances is commonly associated with pain. Inflammatory pain is mainly caused by the direct effect of inflammatory mediators on particular classes of nociceptive neurons. In the current investigation, the antinociceptive and anti-inflammatory effect of corynoline, a phytochemical compound isolated from Corydalis bungeana Turcz., has been evaluated in experimental mice. The experimental mice were divided into 5 groups of 6 animals each. The first control group was fed with water. The second, third, and fourth groups received different doses of corynoline and the fifth group of mice received positive controls. Nociception was induced with the help of acetic acid, formalin, glutamate, capsaicin, hot plate, and tail immersion in mice whereas carrageenan was used to induce inflammation. The peritoneal cavity leukocyte infiltration and pro-inflammatory mediator generation were also analyzed to confirm the anti-inflammatory effect and the natural locomotor activity was determined using an open field test. Corynoline treatment significantly suppressed the paw licking, writhing in the abdominal region, and displayed high nociceptive inhibitory reaction in a dose-related manner. Additionally, corynoline significantly reduced the carrageenan-triggered paw edema and also reduced the levels of pro-inflammatory cytokines. Thus, the antinociceptive and anti-inflammatory activity of corynoline has been successfully established.

Activation of Nrf2/HO-1 signaling: An important molecular mechanism of herbal medicine in the treatment of atherosclerosis via the protection of vascular endothelial cells from oxidative stress

Introduction

Recently, Nrf2/HO-1 has received extensive attention as the main regulatory pathway of intracellular defense against oxidative stress and is considered an ideal target for alleviating endothelial cell (EC) injury.

Objectives

This paper aimed to summarized the natural monomers/extracts that potentially exert protective effects against oxidative stress in ECs.

Methods

A literature search was carried out regarding our topic with the keywords of “atherosclerosis” or “Nrf2/HO-1” or “vascular endothelial cells” or “oxidative stress” or “Herbal medicine” or “natural products” or “natural extracts” or “natural compounds” or “traditional Chinese medicines” based on classic books of herbal medicine and scientific databases including Pubmed, SciFinder, Scopus, the Web of Science, GoogleScholar, BaiduScholar, and others. Then, we analyzed the possible molecular mechanisms for different types of natural compounds in the treatment of atherosclerosis via the protection of vascular endothelial cells from oxidative stress. In addition, perspectives for possible future studies are discussed.

Results

These agents with protective effects against oxidative stress in ECs mainly include phenylpropanoids, flavonoids, terpenoids, and alkaloids. Most of these agents alleviate cell apoptosis in ECs due to oxidative stress, and the mechanisms are related to Nrf2/HO-1 signaling activation. However, despite continued progress in research on various aspects of natural agents exerting protective effects against EC injury by activating Nrf2/HO-1 signaling, the development of new drugs for the treatment of atherosclerosis (AS) and other CVDs based on these agents will require more detailed preclinical and clinical studies.

Conclusion

Our present paper provides updated information of natural agents with protective activities on ECs against oxidative stress by activating Nrf2/HO-1. We hope this review will provide some directions for the further development of novel candidate drugs from natural agents for the treatment of AS and other CVDs.

Corynoline protects lipopolysaccharide-induced mastitis through regulating AKT/GSK3β/Nrf2 signaling pathway

Inflammation has been known to be involved in the pathogenesis of mastitis. And anti-inflammatory agent is proposed to be a possible efficient therapeutic strategy for mastitis. Corynoline, a bioactive compound extracted from Corydalis bungeana Turcz., has been reported to have anti-inflammatory effect. However, whether corynoline has protective effect against mastitis remains unclear. The aim of this study was to evaluate the protective effect of corynoline on LPS-induced mastitis in mice. Inflammatory cytokine production was measured by ELISA. The proteins of signaling pathways were detected by western blot analysis. The results showed that treatment of corynoline at the doses of 15, 30, and 60 mg/kg significantly attenuated LPS-induced pathological damage of mammary tissues. Corynoline also ameliorated LPS-induced MPO activity, MDA content, and inflammatory cytokine TNF-α and IL-1β production in mammary tissues. LPS-induced NF-κB activation was inhibited by corynoline. Furthermore, our results showed corynoline significantly increased the expression of Nrf2 and the phosphorylation levels of AKT and GSK3β. In conclusion, our results indicated that corynoline protected against LPS-induced mastitis through regulating AKT/GSK3β/Nrf2 signaling pathway, which subsequently led to the inhibition of NF-κB and inflammatory response.

Berberine attenuates the inflammatory response by activating the Keap1/Nrf2 signaling pathway in bovine endometrial epithelial cells

Endometritis is a common inflammatory disease that disturbs the rapid development of dairy farming. In the present study, we investigated the anti-inflammatory effects of berberine on the LPS-induced inflammatory response in bovine endometrial epithelial cells (bEECs) and the participation of the Keap1/Nrf2 signaling pathway in this process. Berberine treatment significantly reduced the LPS-induced expression levels of CRP, IL-1β, IL-6, and TNF-α in bEECs. The Nrf2 signaling pathway in these cells was also activated by berberine. We further evaluated the effects of Nrf2 activators and inhibitors on the downregulation of proinflammatory cytokines. The activator of Nrf2 significantly inhibited the production of these proinflammatory cytokines that was induced by LPS. However, an inhibitor of Nrf2 only partially inhibited the anti-inflammatory effects of berberine on the LPS-induced inflammatory response in bEECs. In conclusion, our findings suggest that berberine exerts anti-inflammatory effects partially by activating the Keap1/Nrf2 signaling pathway.

Systematic review of the alkaloid constituents in several important medicinal plants of the Genus Corydalis

The genus Corydalis is a botanical source of various pharmaceutically active components. Its member species have been widely used in traditional medicine systems in Southeast Asia, especially in China for thousands of years. They have been administered to treat the common cold, hypertension, hepatitis, hemorrhage, edema, gastritis, cardiovascular and cerebrovascular diseases, and neurological disorders. Analgesia is the most important effect of Corydalis products, which are relatively non-addictive and associated with low tolerance compared with other analgesics. Certain Corydalis species are rich in alkaloids, which have strong biological activity, and also contain coumarins, flavonoids, steroids, organic acids and other chemical components. These constituents have pharmacological efficacy against diseases of the nervous, cardiovascular and digestive systems. Numerous investigations have been performed on these plants and their components. Here, we systemically summarized the chemical constituents of important medicinal member species of Corydalis that have been reported since 1962. A total 381 alkaloids were enumerated, including 117 quaternary isoquinoline type, 60 Benzophenanthridine type, 37 aporphine type, 10 protopine type, 59 phthalide isoquinoline type, 52 simple isoquinoline-type, 25 lignin amides and 21 other alkaloids. Thus, we have provided a basis for further explorations into the pharmacologically active constituents of Corydalissp.(Papaveraceae) to develop medicines that exert strong effects, are relatively non-addictive, and result in few side effects.

Repurposing existing drugs for the treatment of COVID-19/SARS-CoV-2 infection: A review describing drug mechanisms of action

The outbreak of a novel coronavirus (SARS-CoV-2) has caused a major public health concern across the globe. SARS-CoV-2 is the seventh coronavirus that is known to cause human disease. As of September 2020, SARS-CoV-2 has been reported in 213 countries and more than 31 million cases have been confirmed, with an estimated mortality rate of ∼3%. Unfortunately, a drug or vaccine is yet to be discovered to treat COVID-19. Thus, repurposing of existing cancer drugs will be a novel approach in treating COVID-19 patients. These drugs target viral replication cycle, viral entry and translocation to the nucleus. Some can enhance innate antiviral immune response as well. Hence this review focuses on comprehensive list of 22 drugs that work against COVID-19 infection. These drugs include fingolimod, colchicine, N4-hydroxycytidine, remdesivir, methylprednisone, oseltamivir, icatibant, perphanizine, viracept, emetine, homoharringtonine, aloxistatin, ribavirin, valrubicin, famotidine, almitrine, amprenavir, hesperidin, biorobin, cromolyn sodium, and antibodies- tocilzumab and sarilumab. Also, we provide a list of 31 drugs that are predicted to function against SARS-CoV-2 infection. In summary, we provide succinct overview of various therapeutic modalities. Among these 53 drugs, based on various clinical trials and literature, remdesivir, nelfinavir, methylpredinosolone, colchicine, famotidine and emetine may be used for COVID-19. SIGNIFICANCE: It is of utmost important priority to develop novel therapies for COVID-19. Since the effect of SARS-CoV-2 is so severe, slowing the spread of diseases will help the health care system, especially the number of visits to Intensive Care Unit (ICU) of any country. Several clinical trials are in works around the globe. Moreover, NCI developed a recent and robust response to COVID-19 pandemic. One of the NCI's goals is to screen cancer related drugs for identification of new therapies for COVID-19. https://www.cancer.gov/news-events/cancer-currents-blog/2020/covid-19-cancer-nci-response?cid=eb_govdel.

Natural product corynoline suppresses melanoma cell growth through inducing oxidative stress

Natural product corynoline is a unique isoquinoline alkaloid extracted from traditional Chinese medicine Corydalis bungeana Turcz, whereas its anticancer properties have not been investigated. In this study, we found that corynoline potently impairs the growth of melanoma cells, B16F10, and A375 in a concentration-dependent manner. Treatment of melanoma cells with corynoline results in G2 cell arrest accompanied by reduced cdc2 activation. Furthermore, corynoline triggers apoptosis of melanoma cells, which is associated with increased expression of Bax and cleaved caspase-3. Mechanistic study indicates that corynoline strongly induces reactive oxygen species (ROS) generation and subsequent DNA damage as evidenced by γ-H2AX accumulation. Notably, the effect of corynoline on melanoma cell cycle and apoptosis is abolished by a ROS scavenger N-acetyl cysteine (NAC), indicating a ROS-dependent mechanism. Finally, corynoline significantly inhibits in vivo B16F10 melanoma tumor growth accompanied by reduced expression of Ki-67 in tumor tissue. Taken together, our data suggest that corynoline suppresses melanoma cell growth in vitro and in vivo by inducing oxidative stress and represents a potential therapeutic agent for melanoma patients.

Ultrahigh Performance Liquid Chromatography-Electrospray Ionization Tandem Mass Spectrometry Method for Qualitative and Quantitative Analyses of Constituents of Corydalis bungeana Turcz Extract

In this study, the constituents of a Corydalis bungeana Turcz extract were qualitatively analyzed using gradient elution with a mobile phase of 0.2% acetic acid and acetonitrile. We obtained comprehensive insight into the constituents of C. bungeana Turcz extracts through the quantitative analysis of 14 compounds by comparison with authentic reference standards, and tentatively identified an additional 44 compounds through electrospray ionization mass spectrometry (ESI-MS) and tandem MS detection. The separation was successfully achieved using an Agilent SB-C₁₈ column (1.8 µm, 150 × 2.1 mm; Agilent, Santa, CA, USA). A tandem quadrupole spectrometer was operated in either full-scan mode or multiple reaction monitoring (MRM) for the qualitative and quantitative analyses of the constituents, respectively. Validation data (inter-day and intra-day combined) for accuracy and precision ranged from -4.80% to 4.73%, and 0.30% to 4.97%, respectively. An ultrahigh performance liquid chromatographic-ESI-tandem MS (UHPLC-ESI-MS/MS) method for qualitative of C. bungeana Turcz (C. bungeana) extract and the quantification of 14 alkaloids, namely, A-N, was developed and validated. Quantitative analysis involved gradient elution with a mobile phase of 0.1% acetic acid and methanol for 45 min. The separation was successfully achieved using a Waters SB-C₁₈ column (1.8 µm, 100 mm × 2.1 mm, Waters, Milford, Massachusetts, USA). The repeatability and stability of the method also met USFDA criteria with CV values lower than 5%. The limit of detection of the 14 alkaloids ranged from 9.74 to 13.00 ng/mL, whereas the linearities of the standard curves were between 0.9991 and 0.9995. In total, 15 commercial samples from 11 different sources were analyzed.