Effects of osthol on blood pressure and lipid metabolism in stroke-prone spontaneously hypertensive rats

6-methylcoumarin/miR-122 suppresses hepatic Sortilin-mediated ApoB-100 secretion to attenuate aortic atherosclerosis

This study aimed to investigate the effects of hepatic microRNA-122 (miR-122) on Sortilin-mediated apolipoprotein B100 (apoB-100) secretion, and on aortic lipid deposition and atherosclerosis (AS) lesions and to clarify the antiatherosclerotic mechanism of 6-methylcoumarin (6-MC) via the modulation of miR-122. Bioinformatics analysis revealed that miR-122 was putatively overexpressed in a liver-specific manner and was downregulated in steatotic livers. miR-122 was shown to suppress the expression of Sortilin by complementarily pairing to the 3'-untranslated region (3'-UTR) of Sortilin mRNA via bioinformatics and dual-luciferase reporter assays, impeding Sortilin-mediated apoB-100 secretion from HepG2 cells. Administration of 6-MC significantly upregulated hepatocellular miR-122 levels, reducing Sortilin expression and apoB-100 secretion in HepG2 cells. The miR-122 mimic vigorously enhanced 6-MC-depressed Sortilin expression, while miR-122 inhibitor repealed the inhibitory effect of 6-MC on Sortilin expression to some extent in HepG2 cells. After internal intervention with the miR-122 precursor, and 6-MC supplementation alone or in combination with the miR-122 sponge led to the reduction in blood triglyceride (TG) levels, low-density lipoprotein-cholesterol (LDL-C) and apoB-100 and a reduction in aortic lipid deposition and AS lesions in apolipoprotein E-deficient (ApoE-/-) mice fed a high fat diet (HFD). The hepatic levels of Sortilin and apoB-100 expression were also decreased in these treated mice. In conclusion, miR-122 suppresses Sortilin expression and Sortilin-mediated apoB-100 secretion to resist circulating LDL production and aortic AS development, which is enhanced by 6-MC-upregulated miR-122 in the liver.

New coumarin from the roots of Prangos pabularia growing wild in Tajikistan

Dichloromethane and butanol extracts of the roots of Prangos pabularia were analyzed to determine chemical constituents and biological activity. The new coumarin 1, yuganin B ((5-(((2S,3R,4S,5S,6R)-4,5-dihydroxy-6-(hydroxymethyl)-2-((2-oxo-2H-chromen-7-yl)oxy)tetrahydro-2H-pyran-3-yl)oxy)-3,4-dihydroxytetrahydrofuran-3-yl)methyl 4-hydroxy-3-methoxybenzoate) along with three phenolic and twenty-four known coumarins were isolated from the roots of Prangos pabularia, and the structures of these isolated compounds were elucidated by UV, HR-ESIMS, and 1 D and 2 D NMR spectroscopy. In addition, the anti-melanogenic effect of several of the isolated individual compounds and their inhibitory effect on B16 cells were evaluated. Isolating and testing compounds may proof to be useful in the treatment of hyperpigmentation and as a skin-whitening agent in the cosmetics industry.

Inhibition of Glycogen Synthase Kinase and the Neuroprotective Function of Conjugated ZnO-Osthol Nanoparticles in Alzheimer’s Disease

A critical factor in the cause and progression of Alzheimer’s disease (AD) is the growth of β-amyloid peptide (Aβ) in the brain. The mechanism of this effect is still unknown, although the effect of osthol on Aβ-induced inflammation is neuroprotective in AD and supplementation with zinc might prevent or delay the onset of dementia. In the current study, by inducing APP vector in human BE (2)-M17 cells, we established a cellular model of AD and investigated the protective effect of osthol (7-methoxy-8-3-methyl-2-butenyl-2H-1-benzopyran-2-one)-zinc oxide nanoparticles. The osthol-conjugated zinc oxide nanoparticles could significantly increase cell viability by inhibiting cell apoptosis. Osthol treatment has also prevented synaptic proteins such as postsynaptic density-95 (PSD-95), synaptophysin (SYP), and synapsin-1 from decreasing in APP-induced BE (2)-M17 cells. In addition, the expression of miR-132 was significantly upregulated by osthol by triggering the Wnt/β-catenin signaling pathway. We conclude from our observations that osthol is a potential drug for the treatment of a neurodegenerative disease, Alzheimer’s. The key reason was that by upregulating miR-132, osthol could inhibit APP expression to prevent AD from occurring.

The Genus Deverra DC. (Syn. Pituranthos Viv.): A natural valuable source of bioactive phytochemicals: A review of traditional uses, phytochemistry and pharmacological properties

The genus Deverra DC. (Apiaceae) comprising only 13 taxa (9 species and 4 subspecies level) with disjunctive distribution in South Africa, in North Africa to Arabian Ecoregion. Thesis, books, Scientific journals, and reports were referred to collect information on the Deverra species. This present work reviewed the literature from 1900 to the end of January 2021. The aim of the review is to highlight traditional uses, phytochemistry and pharmacological properties of the species of the genus. The ethnopharmacologial uses of plant taxa belonging to this genus indicated that plant extracts, Essentail Oils (EOs) and infusion of aerial parts (APs) have been used in traditional popular medicine. The plants are used as a treatment of various purposes, such as asthma, rheumatism, fevers, hepatitis, diabetes and digestive difficulties. This present work focuses on ethnopharmacology of the Deverra species, the phytochemistry, pharmacology, toxicology among other studies on the genus. The present article summarizes on known and potential effects of the Deverra species as well as traditional medicine uses corroborated with pharmacological evidences. By the end of the review, Deverra species have a large application of bioactivities and the most described activities of Deverra plants are attributed to the presence of essential oils, coumarins, furocoumarins, flavonoids and phenolics. CONCLUSIONS: The review confirms that some Deverra taxa have been reported as a valuable source for flavoring and as a condiment as well as in the traditional medicine for the treatment of hypertension, to relief stomach pain and against intestinal parasites against spasms, pains, diabetes, hepatitis, digestive difficulties, urinary infections … etc. Nonetheless, for the valorisation of Deverra species in order to prevent and treat various diseases, further pharmacological investigations are strongly required to determine the mechanism of action, test the safety and the efficacity before starting clinical trials at big scale.

The Protective Effect of Natural Compounds on Doxorubicin-Induced Cardiotoxicity via Nicotinamide Adenine Dinucleotide Phosphate Oxidase Inhibition

OBJECTIVES

Doxorubicin (DOX) is widely prescribed for the treatment of several human cancers. Unfortunately, cumulative doses of DOX are the main cause of myocardial dysfunction. Although preclinical and pharmaceutical studies were performed to investigate the potential of natural compounds in minimizing DOX toxicity, a comprehensive review of them is not available. This review can help the researchers for an effective search strategy.

KEY FINDINGS

Oxidative stress and p53 play an important role in DOX-associated cardiotoxicity. DOX activates nicotinamide adenine dinucleotide phosphate NADPH oxidase (NOX) in the heart, resulting in excessive reactive oxygen species that can induce cardiomyocyte apoptosis through phosphorylation of p53, DNA damage and/or mitogen-activated protein kinases-mediated cardiomyocyte apoptosis. Although a few chemical drugs with high efficacy are administered along with DOX to prevent or more likely to reduce cardiovascular toxicity, their use is often limited by additional side effects. Recently, attention has been drawn to natural compounds that prevent DOX cardiotoxicity. This review focuses on some of the natural bioactive compounds with potential therapeutic efficacy against DOX-induced cardiotoxicity (DIC).

SUMMARY

Some natural compounds, especially flavonols, flavonoids and proanthocyanidins, have the most protective effects against DIC by forming stable radicals and preventing the assembly of the NOX subunits.

Construction of oxime ester derivatives of osthole from Cnidium monnieri, and evaluation of their agricultural activities and control efficiency

BACKGROUND

In order to discover natural-product-based pesticidal candidates, a series of coumarin-like derivatives containing oxime ester fragments at the C-8 position were prepared by structural modification of osthole, a natural plant product isolated from Cnidium monnieri. Their pesticidal activities were evaluated against two typically fruit trees/crop-threatening agricultural pests, Mythimna separata Walker and Tetranychus cinnabarinus Boisduval.

RESULTS

Osthole was regioselectively oxidized by selenium dioxide to give the E-isomer, (2'E)-3'-formaldehydylosthole (2). Four key steric structures of 2, (2'E, 4'E)-(o-chloropyrid-3-ylcarbonyl)oximinylosthole (4o), (2'E, 4'E)-(styrylcarbonyl)oximinylosthole (4t), and (2'E, 4'E)-(acetyl)oximinylosthole (4w) were undoubtedly confirmed by X-ray crystallography. Against T. cinnabarinus, it is noteworthy that (2'E, 4'E)-(p-chlorophenylcarbonyl)oximinylosthole (4c) exhibited over three-fold more potent acaricidal activity of the precursor osthole, with especially good control efficiency observed in the glasshouse. Against M. separata, compounds 4c and (2'E, 4'E)-(p-nitrophenylcarbonyl)oximinylosthole (4f) showed the most pronounced growth inhibitory activity. The relationships between their structures and agricultural activities also were studied.

CONCLUSION

These results demonstrate that compound 4c could be further structurally modified as pesticidal agents. It will lay the foundation for future application of osthole derivatives as pesticides. © 2020 Society of Chemical Industry.

Phytochemistry, Ethnopharmacology, Pharmacokinetics and Toxicology of Cnidium monnieri (L.) Cusson

Cnidium monnieri (L.) Cusson (CMC) is a traditional Chinese herbal medicine that has been widely grown and used in Asia. It is also known as "She chuang zi" in China (Chinese: ), "Jashoshi" in Japan, "Sasangia" in Korea, and "Xa sang tu" in Vietnam. This study aimed to provide an up-to-date review of its phytochemistry, ethnopharmacology, pharmacokinetics, and toxicology. All available information on CMC was collected from the Encyclopedia of Traditional Chinese Medicines, PubMed, EMBASE, ScienceDirect, Scopus, Web of Science, and China Network Knowledge Infrastructure. The updated chemical structures of the compounds are those ones without chemical ID numbers or references from the previous review. A total of 429 chemical constituents have been elucidated and 56 chemical structures have been firstly identified in CMC with traceable evidence. They can be categorized as coumarins, volatile constituents, liposoluble compounds, chromones, monoterpenoid glucosides, terpenoids, glycosides, glucides, and other compounds. CMC has demonstrated impressive potential for the management of various diseases in extensive preclinical research. Since most of the studies are overly concentrated on osthole, more research is needed to investigate other chemical constituents.

Osthole relieves diabetics cardiac autonomic neuropathy associated with P2X3 receptor in ratstellate ganglia

Diabetic cardiac autonomic neuropathy (DCAN) is a serious complication of diabetes mellitus, which often leads to cardiac dysfunction and even threatens patients' life. Osthole, a natural coumarin derivative, has anti-inflammatory, anti-oxidant and antihypertensive effects. The P2X3 receptor is related to DCAN. The objective of this study will investigate whether osthole relieves DCAN associated with the P2X3 receptor in the stellate ganglia of diabetic rats. A type 2 diabetes mellitus rat model was induced by a combination of diet and streptozotocin. Our results showed that osthole improved the abnormal changes of blood pressure, heart rate, and heart rate variability in diabetic rats and significantly reduced the up-regulated expression levels of the P2X3 receptor, tumor necrosis factor-α and interleukin-1β in stellate ganglia of diabetic rats. Meanwhile, osthole significantly decreased the elevated serum adrenaline concentration and phosphorylation level of extracellular regulated protein kinase 1/2. In addition, the molecular docking result indicated that osthole was a perfect fit for interacting with the P2X3 receptor. Overall, osthole alleviates the sympathetic relative excitation via inhibiting the expression of P2X3 receptors in the stellate ganglia, to achieve a balance between sympathetic and parasympathetic nerves, relieves the DCAN.

Metabolic map of osthole and its effect on lipids

1. Osthole, a coumarin compound from plants, is a promising agent for the treatment of metabolic diseases, including hyperglycemia, fatty liver, and cancers. Studies indicate that the peroxisome proliferator-activated receptors (PPAR) α and γ are involved in the pharmacological effects of osthole. The in vitro and in vivo metabolism of osthole and its biological activity are not completely understood. 2. In this study, ultra-performance chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI-QTOFMS)-based metabolomics was used to determine the metabolic pathway of osthole and its influence on the levels of endogenous metabolites. Forty-one osthole metabolites, including 23 novel metabolites, were identified and structurally elucidated from its metabolism in vitro and in vivo. Recombinant cytochrome P450s (CYPs) screening showed that CYP3A4 and CYP3A5 were the primary enzymes contributing to osthole metabolism. 3. More importantly, osthole was able to decrease the levels of lysophosphatidylethanolamine (LPE) and lysophosphatidylcholine (LPC) in the plasma, which explains in part its modulatory effects on metabolic diseases. 4. This study gives the insights about the metabolic pathways of osthole in vivo, including hydroxylation, glucuronidation, and sulfation. Furthermore, the levels of the lipids regulated by osthole indicated its potential effects on adipogenesis. These data contribute to the understanding of the disposition and pharmacological activity of osthole in vivo.

Osthole attenuates lipid accumulation, regulates the expression of inflammatory mediators, and increases antioxidants in FL83B cells

Osthole is found in Cnidium monnieri (L.) and has anti-inflammatory and anti-oxidative properties. It also inhibits the proliferation of hepatocellular carcinoma cells. This study aimed to evaluate the osthole suppressive nonalcoholic fatty liver disease effects in oleic acid (OA)-induced hepatic steatosis and if it can modulate inflammatory responses and oxidative stress. FL83B cells were pretreated with OA (250μΜ) for 24h, and then added different concentrations of osthole (3-100μM) for 24h. Subsequently, lipolysis and transcription factors of adipogenesis and phosphorylation of AMP-activated protein kinase proteins were measured. In addition, cells with OA-induced steatosis were H₂O₂-stimulated, and then incubated with osthole to evaluated if it could suppress its progression to steatohepatitis. Osthole significantly enhanced glycerol release and lipolysis protein expression. Osthole also promoted phosphorylation of AMP-activated protein kinases and increased the activity of triglyceride lipase and hormone- sensitive lipase. Osthole suppressed the nuclear transcription factor kappa-B and the p38 mitogen-activated protein kinase pathway, and decreased the malondialdehyde concentration in FL83B cells with OA-induced steatosis that were treated with H₂O₂. These results suggest that osthole might suppress nonalcoholic fatty liver disease by decreasing lipid accumulation, and through its anti-oxidative and anti-inflammatory effects via blocked NF-κB and MAPK signaling pathways.

Antileishmanial activity of prenylated coumarins isolated from Ferulago angulata and Prangos asperula

Leishmaniasis has a wide spectrum of signs and symptoms due to infection to numbers of Leishmania species and makes enormous mortality and morbidity. There are clues of antileishmanial effects of prenylated coumarins. Apiaceae family is one of the most important sources of coumarins. Air-dried aerial parts of Ferulago angulata and fruits of Prangos asperula were extracted with n-hexane, using a soxhlet apparatus. The solvents were evaporated under reduced pressure. Column chromatography and crystallization process resulted to isolation of three prenylated coumarins. ¹H-nuclear magnetic resonance, electron ionization Mass and Infrared spectra were used for elucidation of isolated compounds. Leishmanicidal activity of isolated coumarins was assessed on Leishmania major strain (MRHO/IR/75/ER) for the first time. Suberosin epoxide and suberosin were isolated from aerial parts of F. angulata and osthol was extracted from grounded fruits of P. asperula. Osthol showed a significant antileishmanial effect on promastigotes in early hours of exposure with IC₅₀ of 14.40 µg/mL but suberosin epoxide showed only a weak antileishmanial activity. IC₅₀ of osthol and suberosin epoxide after 48 h were 10.79 and 54.0 µg/mL, respectively. Suberosin showed no remarkable effect in these concentrations. This is the first report on the pharmacological activity of suberosin epoxide. Substantial difference between efficacies of two isomers, osthol and suberosin remarks the importance of prenyl substituent location on C-8.

Anti-Hypertensive Herbs and Their Mechanisms of Action: Part II

Traditional medicine has a history extending back to thousands of years, and during the intervening time, man has identified the healing properties of a very broad range of plants. Globally, the use of herbal therapies to treat and manage cardiovascular disease (CVD) is on the rise. This is the second part of our comprehensive review where we discuss the mechanisms of plants and herbs used for the treatment and management of high blood pressure. Similar to the first part, PubMed and ScienceDirect databases were utilized, and the following keywords and phrases were used as inclusion criteria: hypertension, high blood pressure, herbal medicine, complementary and alternative medicine, endothelial cells, nitric oxide (NO), vascular smooth muscle cell (VSMC) proliferation, hydrogen sulfide, nuclear factor kappa-B (NF-κB), oxidative stress, and epigenetics/epigenomics. Each of the aforementioned keywords was co-joined with plant or herb in question, and where possible with its constituent molecule(s). This part deals in particular with plants that are used, albeit less frequently, for the treatment and management of hypertension. We then discuss the interplay between herbs/prescription drugs and herbs/epigenetics in the context of this disease. The review then concludes with a recommendation for more rigorous, well-developed clinical trials to concretely determine the beneficial impact of herbs and plants on hypertension and a disease-free living.

Cnidium monnieri: A Review of Traditional Uses, Phytochemical and Ethnopharmacological Properties

Cnidium monnieri (L.) Cuss., an annual plant of the Umbelliferae species is one of the most widely used traditional herbal medicines and its fruits have been used to treat a variety of diseases in China, Vietnam, and Japan. The aim of this review is to provide an up-to-date and comprehensive analysis of the botany, traditional uses, phytochemistry, pharmacology, toxicity and contraindication of Cnidium monnieri (L.) Cuss. and to provide future directions of research on this plant. To date, 350 compounds have been isolated and identified from Cnidium monnieri (L.) Cuss., including the main active constituent, coumarins. In vitro and in vivo studies suggest that osthole and other coumarin compounds possess wide range of pharmacological properties for the treatment of female genitals, male impotence, frigidity, skin-related diseases, and exhibit strong antipruritic, anti-allergic, antidermatophytic, antibacterial, antifungal, anti-osteoporotic effects. Although coumarins have been identified as the main active constituents responsible for the observed pharmacological effects, the molecular mechanisms of their actions are still unknown. Therefore, further studies are still required to reveal the structure-activity relationship of these active constituents. In addition, toxicological and clinical studies are also required to provide further data for pharmaceutical use.

Osthole: A Review on Its Bioactivities, Pharmacological Properties, and Potential as Alternative Medicine

This paper reviews the latest understanding of biological and pharmacological properties of osthole (7-methoxy-8-(3-methyl-2-butenyl)-2H-1-benzopyran-2-one), a natural product found in several medicinal plants such as Cnidium monnieri and Angelica pubescens. In vitro and in vivo experimental results have revealed that osthole demonstrates multiple pharmacological actions including neuroprotective, osteogenic, immunomodulatory, anticancer, hepatoprotective, cardiovascular protective, and antimicrobial activities. In addition, pharmacokinetic studies showed osthole uptake and utilization are fast and efficient in body. Moreover, the mechanisms of multiple pharmacological activities of osthole are very likely related to the modulatory effect on cyclic adenosine monophosphate (cAMP) and cyclic adenosine monophosphate (cGMP) level, though some mechanisms remain unclear. This review aims to summarize the pharmacological properties of osthole and give an overview of the underlying mechanisms, which showcase its potential as a multitarget alternative medicine.

General Practitioners' vitamin K antagonist monitoring is associated with better blood pressure control in patients with hypertension--a cross-sectional database study

Background

Patients requiring anticoagulation suffer from comorbidities such as hypertension. On the occasion of INR monitoring, general practitioners (GPs) have the opportunity to control for blood pressure (BP). We aimed to evaluate the impact of Vitamin-K Antagonist (VKA) monitoring by GPs on BP control in patients with hypertension.

Methods

We cross-sectionally analyzed the database of the Swiss Family Medicine ICPC Research using Electronic Medical Records (FIRE) of 60 general practices in a primary care setting in Switzerland. This database includes 113,335 patients who visited their GP between 2009 and 2013. We identified patients with hypertension based on antihypertensive medication prescribed for ≥6 months. We compared patients with VKA for ≥3 months and patients without such treatment regarding BP control. We adjusted for age, sex, observation period, number of consultations and comorbidity.

Results

We identified 4,412 patients with hypertension and blood pressure recordings in the FIRE database. Among these, 569 (12.9 %) were on Phenprocoumon (VKA) and 3,843 (87.1 %) had no anticoagulation. Mean systolic and diastolic BP was significantly lower in the VKA group (130.6 ± 14.9 vs 139.8 ± 15.8 and 76.6 ± 7.9 vs 81.3 ± 9.3 mm Hg) (p < 0.001 for both). The difference remained after adjusting for possible confounders. Systolic and diastolic BP were significantly lower in the VKA group, reaching a mean difference of −8.4 mm Hg (95 % CI −9.8 to −7.0 mm Hg) and −1.5 mm Hg (95 % CI −2.3 to −0.7 mm Hg), respectively (p < 0.001 for both).

Conclusions

In a large sample of hypertensive patients in Switzerland, VKA treatment was independently associated with better systolic and diastolic BP control. The observed effect could be due to better compliance with antihypertensive medication in patients treated with VKA. Therefore, we conclude to be aware of this possible benefit especially in patients with lower expected compliance and with multimorbidity.

Inhibitory effects of Cnidium monnieri fruit extract on pulmonary inflammation in mice induced by cigarette smoke condensate and lipopolysaccharide

The aim of this study was to investigate the inhibitory effect of Cnidium monnieri fruit (CM) extracts on pulmonary inflammation induced in mice by cigarette smoke condensate (CSC) and lipopolysaccharide (LPS). Pulmonary inflammation was induced by intratracheal instillation of LPS and CSC five times within 12 days. CM extract was administered orally at a dose of 50 or 200 mg·kg(-1). The number of inflammatory cells in the bronchoalveolar lavage fluid was counted using a fluorescence activated cell sorter. Inflammatory mediator levels were determined by enzyme-linked immunosorbent assay. The administration of LPS and CSC exacerbated airway hyper-responsiveness (AHR) and induced an accumulation of inflammatory cells and mediators, and led to histological changes. However, these responses are modulated by treatment with CM, and the treatment with CM extract produces similar or more extensive results than the treatment with cyclosporin A (CSA). CM extract may have an inhibitory effect on pulmonary inflammation related with chronic obstructive pulmonary disease.

Antiviral and cytotoxic evaluation of coumarins from Prangos ferulacea

CONTEXT

Prangos ferulacea (L.) Lindl. (Apiaceae) is a perennial plant found in the Middle-East, where it is commonly used as an antispasmodic and anti-inflammatory agent. It is a rich source of coumarins.

OBJECTIVE

To purify several coumarins from P. ferulacea and to screen their cytotoxicity and anti-herpes activity.

MATERIALS AND METHODS

Acetone extract of roots of P. ferulacea was subjected to several chromatographic separations to render pure coumarins (1-8). Anti-herpes virus effects of 1-7 were evaluated at concentration 2.5, 5, and 10 µgmL(-1), on a confluent monolayer of Vero cells infected with 25 PFU of HSV1. Cytotoxic effects of 1 and 2 were evaluated on an A2780S cell line using the MTT assay. The cells were exposed to a series of concentrations of coumarins (0.01-2.5 mM, 37°C, 72 h).

RESULTS

Compounds 1-8 were identified as osthole, isoimperatorin, oxypeucedanin, psoralen, oxypeucedanin hydrate, gosferol, oxypeucedanin methnolate, and pranferol. This is the first report of occurrence of 4 and 7 in this plant. Compound 1 showed a viability of 9.41% ± 2.4 at 2.5 mM on A2780S cells (IC50 = 0.38 mM). The cell survival of 2 at 2.5 mM was 46.86% ± 5.5 with IC50 equal to 1.1 mM.

DISCUSSION AND CONCLUSION

Compound 1 shows cytotoxic effects on the A2780S cell line. Compound 2 is a cyclooxygenase-2 inhibitor and the A2780S cell line does not express COX-2 which may interpret the non-toxic effect of the compound on this cell line. None of the tested compounds showed an anti-HSV effect at non-toxic concentrations.

Osthole attenuates doxorubicin-induced apoptosis in PC12 cells through inhibition of mitochondrial dysfunction and ROS production

Doxorubicin (DOX) is a potent, broad-spectrum chemotherapeutic drug used for treatment of several types of cancers. Despite its effectiveness, it has a wide range of toxic side effects, many of which most likely result from its inherent prooxidant activity. It has been reported that DOX has toxic effects on normal tissues, including brain tissue. In the current study, we investigated the protective effect of osthole isolated from Prangos ferulacea (L.) Lindl. on oxidative stress and apoptosis induced by DOX in PC12 as a neuronal model cell line. PC12 cells were pretreated with osthole 2 h after treatment with different concentrations of DOX. 24 h later, the cell viability, mitochondrial membrane potential (MMP), the activity of caspase-3, the expression ratio of Bax/Bcl-2, and the generation of intracellular ROS were detected. We found that pretreatment with osthole on PC12 cells significantly reduced the loss of cell viability, the activity of caspase-3, the increase in Bax/Bcl-2 ratio, and the generation of intracellular ROS induced by DOX. Moreover, pretreatment with osthole led to an increase in MMP in PC12 cells. In conclusion, our results indicated that pretreatment with nontoxic concentrations of osthole protected PC12 cells from DOX-mediated apoptosis by inhibition of ROS production.

Coumarin attenuates hepatic steatosis by down-regulating lipogenic gene expression in mice fed a high-fat diet

Coumarin is a natural compound abundant in plant-based foods such as citrus fruits, tomatoes, vegetables and green tea. Although coumarin has been reported to exhibit anti-coagulant, anti-inflammation and cholesterol-lowering properties, the effect of coumarin on hepatic lipid metabolism remains unclear. In the present study, we evaluated the ability of coumarin to protect against hepatic steatosis associated with a high-fat diet (HFD) and investigated potential mechanisms underlying this effect. C57BL/6J mice were fed a normal diet, HFD and HFD containing 0·05 % courmarin for 8 weeks. The present results showed that coumarin reduced weight gain and abdominal fat mass in mice fed the HFD for 8 weeks (P< 0·05). Coumarin also significantly reduced the HFD-induced elevation in total cholesterol, apoB, leptin and insulin (P< 0·05). In the liver of HFD-fed mice, coumarin significantly reduced total lipids, TAG and cholesterol (38, 22 and 9 % reductions, respectively; P< 0·05), as well as lipid droplet number and size. Additionally, thiobarbituric acid-reactive substance levels, as an indicator of hepatic steatosis, were attenuated by coumarin (P< 0·05). Finally, coumarin suppressed the HFD-induced up-regulation in fatty acid synthase (FAS) activity, and the expression of sterol regulatory element-binding protein-1, FAS, acetyl-CoA carboxylase 1, PPARγ and CCAAT/enhancer-binding protein-α in the liver. Taken together, these results demonstrate that coumarin could prevent HFD-induced hepatic steatosis by regulating lipogenic gene expression, suggesting potential targets for preventing hepatic steatosis.

Comparative study of pharmacokinetics and tissue distribution of osthole in rats after oral administration of pure osthole and Libanotis buchtormensis supercritical extract

ETHNOPHARMACOLOGICAL RELEVANCE

Libanotis buchtormensis is the source of an important traditional medicine from Shaanxi province of China used in the treatment of many illnesses. Libanotis buchtormensis supercritical extract (LBSE) has analgesic, sedative and anti-inflammatory qualities. Osthole is one of the major bioactive components of LBSE; it is known for its significant anti-tumor, analgesic, and anti-inflammatory properties, it also alleviates hyperglycemia.

AIM OF THE STUDY

The purpose of the present study was to compare the pharmacokinetics and tissue distribution of osthole in Sprague-Dawley (SD) rats after oral administration of pure osthole and LBSE. The two preparations were administered at the same osthole dose (approximately 130 mg/kg). The results should provide some guidance for the clinical applications of Libanotis buchtormensis.

MATERIALS AND METHODS

Comparative pharmacokinetics and tissue distribution of osthole in SD rats after oral administration of pure osthole and LBSE were analyzed using reversed-phase high-performance liquid chromatography (RP-HPLC). All pharmacokinetic data were analyzed using 3P97 software. Samples of blood and internal organs (heart, liver, spleen, lungs and kidney) were collected and pretreated according to the experimental schedule. After pretreatment, plasma and tissue samples were extracted using ether-ethyl acetate mixture (3:1, v/v). The concentration of osthole in the plasma and tissues were determined using the RP-HPLC method.

RESULTS

The procedure described in this paper shows good precision and stability and is suitable for the osthole assays in biological samples. We found that the average plasma concentration-time profile of osthole after oral administration of osthole and LBSE showed a single peak. There were also clear differences between plasma concentrations of osthole after oral administration of pure osthole and LBSE. Non-osthole ingredients in LBSE showed some pharmacokinetic interactions with osthole and hence decreased its absorption levels (p<0.05). Our results show different tissue distribution of osthole in the single and composite administration regimens.

CONCLUSIONS

This study compares the pharmacokinetic characteristics and tissue distribution of osthole in rats after oral administration of pure osthole and LBSE; the results might be useful in clinical application of this traditional Chinese herbal medicine.

Reduction of rat cardiac hypertrophy by osthol is related to regulation of cardiac oxidative stress and lipid metabolism

The objective of this study was to examine the therapeutic effect of osthol, a coumarin compound isolated from the fruit of Cnidium monnieri (L.) Cusson, on cardiac hypertrophy in rats and investigate its potential mechanisms. The rats with cardiac hypertrophy induced by renovascular hypertension were given osthol orally by gavage for 4 weeks. The results showed that in the osthol 20 mg/kg group, the blood pressure, heart weight index and myocardial malondialdehyde content were lowered (p < 0.001, p = 0.002 and p = 0.025, respectively), the myocardial superoxide dismutase and glutathione peroxidase contents were increased (p < 0.001), and the elevated unesterified fatty acids and triacylglycerols in myocardial tissues were decreased (p = 0.017 and p = 0.004, respectively). At the same time, the myocardial peroxisome proliferator-activated receptor (PPAR)-α and carnitine palmitoyltransferase (CPT)-1a mRNA expressions were increased and the myocardial diacylglycerol acyltransferase (DGAT) mRNA expression was decreased in the osthol 20 mg/kg group (p < 0.001). Osthol treatment was associated with a decreased cross-sectional area of cardiomyocytes (p < 0.001). These findings suggest that osthol may exert a therapeutic effect on cardiac hypertrophy in rats, and its mechanisms may be related to the improvement of myocardial oxidative stress and lipid metabolism via regulation of PPARα-mediated target gene expressions including an increase in CPT-1a mRNA expression and a decrease in DGAT mRNA expression.

Synthesis and anthelmintic activity of osthol analogs against Dactylogyrus intermedius in goldfish

In an attempt to develop novel anthelmintic agents, our previously isolated osthol was used as lead structures for further optimization. In our research, a series of coumarin analogs, prepared from 7-hydroxy coumarin or 7-hydroxy-4-methyl coumarin, have been evaluated for their anthelmintic activities. In all of the compounds, 6 and 7 were first synthesized, and their structures were identified based on NMR and MS values. Among the candidates, 8-allyl-7-allyloxycoumarin showed better anthelmintic activity than other compounds against Dactylogyrus infestation with EC(50) value of 1.81 mg/L. The quantitative structure-activity relationship (QSAR) of 16 osthol analogs with anthelmintic activity expressed as pEC(50) and toxicity to goldfish expressed pLC(50), such results can offer useful theoretical references for future experimental works.

Reduction of isoprenaline-induced myocardial TGF-β1 expression and fibrosis in osthole-treated mice

Peroxisome proliferator-activated receptor (PPAR) α and PPARγ ligands can attenuate myocardial fibrosis. Osthole, an active constituent isolated from the fruit of Cnidium monnieri (L.) Cusson, may be a dual PPARα/γ agonist, but there has been no report on its effect on myocardial fibrosis. In the present study, we investigated the inhibitory effect of osthole on myocardial fibrotic formation in mice and its possible mechanisms. A mouse model with myocardial fibrosis was induced by hypodermic injection of isoprenaline while the mice were simultaneously treated with 40 and 80 mg/kg osthole for 40 days. After the addition of osthole, the cardiac weight index and hydroxyproline content in the myocardial tissues were decreased, the degree of collagen accumulation in the heart was improved, and the downregulation of myocardial PPARα/γ mRNA expression induced by isoprenaline was reversed. Moreover, the mRNA expression of transforming growth factor (TGF)-β1 and the protein levels of nuclear factor (NF)-κB and TGF-β1 in the myocardial tissues were decreased. These findings suggest that osthole can prevent isoprenaline-induced myocardial fibrosis in mice, and its mechanisms may be related to the reduction of TGF-β1 expression via the activation of PPARα/γ and subsequent inhibition of NF-κB in myocardial tissues.

Distinct effects of imperatorin on allergic rhinitis: imperatorin inhibits caspase-1 activity in vivo and in vitro

Because imperatorin (IPT), the furanocoumarins exhibits anti-inflammatory activity, we reasoned that IPT might modulate the allergic rhinitis (AR). The aim of this study was to analyze the regulation of AR by IPT. Here, we show the effect and mechanism of IPT in an ovalbumin (OVA)-induced AR model. The number of rubs after the OVA challenge in the OVA-sensitized mice was significantly higher than that in the OVA-unsensitized mice. The increased number of rubs was inhibited by the oral administration of IPT. The increased levels of IgE and histamine in the OVA-sensitized mice were reduced by IPT administration. The levels of interferon-γ were enhanced, whereas the levels of interleukin (IL)-4 were reduced on the spleen tissue of the IPT-administered AR mice. Protein levels of IL-1β, macrophage inflammatory protein-2, intercellular adhesion molecule-1, and cyclooxygenase-2 were reduced by IPT administration in the nasal mucosa of the OVA-sensitized mice. In the IPT-administered mice, the number of eosinophils and mast cells infiltration increased by OVA-sensitization were also decreased. In addition, IPT inhibited caspase-1 activity in the same nasal mucosa tissue. In activated human mast cells, the receptor-interacting protein 2 (RIP2), IκB kinase (IKK)-β, nuclear factor-κB (NF-κB)/RelA, and caspase-1 activation were increased, but increased RIP2, IKK-β, NF-κB/RelA, and caspase-1 activation were inhibited by the treatment of IPT. In addition, IPT inhibited caspase-1 activity and IL-1β production in IgE-stimulated bone marrow-derived mast cells. We can conclude that IPT exerts significant effects by regulating of caspase-1 activation in AR animal and in vitro models.

Development of a high throughput screen for allosteric modulators of melanocortin-4 receptor signaling using a real time cAMP assay

The melanocortin MC(4) receptor is a potential target for the development of drugs for both obesity and cachexia. Melanocortin MC(4) receptor ligands known thus far are orthosteric agonists or antagonists, however the agonists, in particular, have generally exhibited unwanted side effects. For some receptors, allosteric modulators are expected to reduce side-effect profiles. To identify allosteric modulators of the melanocortin MC(4) receptor, we created HEK293 cell lines coexpressing the human melanocortin MC(4) receptor and a modified luciferase-based cAMP sensor. Monitoring luminescence as a readout of real-time intracellular cAMP concentration, we demonstrate that this cell line is able to report melanocortin agonist responses, as well as inverse agonist response to the physiological AgRP peptide. Based on the MC4R-GLO cell line, we developed an assay that was shown to meet HTS standards (Z'=0.50). A pilot screen run on the Microsource Spectrum compound library (n=2000) successfully identified 62 positive modulators. This screen identified predicted families of compounds: β(2)AR agonists - the β(2)AR being endogenously expressed in HEK293 cells, an adenylyl cyclase activator and finally a distribution of phosphodiesterase (PDE) inhibitors well characterized or recently identified. In this last category, we identified a structural family of coumarin-derived compounds (imperatorin, osthol and prenyletin), along with deracoxib, a drug in veterinary use for its COX2 inhibitory properties. This latter finding unveiled a new off-target mechanism of action for deracoxib as a PDE inhibitor. Overall, these data are the first report of a HTS for allosteric modulators for a Gs protein coupled receptor.

Fast separation and determination of coumarins in Fructus cnidii extracts by CEC using poly(butyl methacrylate-co-ethylene dimethacrylate-co-[2-(methacryloyloxy)ethyl] trimethylammonium chloride) monolithic columns

A rapid CEC method with poly(butyl methacrylate-co-ethylene dimethacrylate-co-[2-(methacryloyloxy)ethyl] trimethylammonium chloride) monolithic column has been developed for separation and determination of four coumarins (isopimpinelline, bergapten, imperatorin, and osthole) in Fructus cnidii extracts. The effect of polymerization condition including the monomers ratio and the porogens ratio were studied. The mobile-phase composition, such as the composition of organic solvent, the concentration and pH of buffer, was also optimized. Under the same condition (50% ACN and 50% of a 10 mM sodium dihydrogen phosphate electrolyte at pH 4.95), in contrast to 25 min of analysis time in HPLC and 10 min of analysis time in pCEC, a fast separation of these analytes was achieved in less than 5 min in CEC. Method validation was developed in accordance with the analytical procedures. Intra- and interday precisions (RSD) for relative retention time and peak area were less than 1.69 and 4.63%, and LODs were lower than 0.5 microg/mL. Calibration curves of four compounds also showed good linearity (r(2)>0.995). The mean recoveries ranged between 93.91 and 98.65%. With this CEC system, the quality of F. cnidii extracts from various resources was evaluated by determining the contents of the four coumarins.

Efficacy of osthol, a potent coumarin compound, in controlling powdery mildew caused by Sphaerotheca fuliginea

The efficacy of osthol, a natural coumarin compound, in controlling powdery mildew was evaluated in 2004-2005 in Anhui and Hebei Provinces of China. In both years, the treatments (osthol 15.0 and 18.0 g ai ha(- 1)) showed a stable control efficiency of 75.42, 81.24% and 76.36, 84.84%, respectively, at the Institutes of Plant Protection of Hebei Academy of Agricultural Sciences. In field experiments, osthol was as effective as difenoconazole in controlling powdery mildew and was more effective than triadimefon against Sphaerotheca fuliginea. Protection was expressed as a significant reduction (up to 87% compared with the control) in the mildewed leaf area in young pumpkin plants. Osthol strongly inhibited spore germination and mycelial growth of S. fuliginea in vitro, damaged the cell wall and the organelles of the pathogen. At 48 h after incubation, 50 microg ml(- 1) osthol could completely inhibit spore germination. These findings suggested that the effect of osthol on powdery mildew may be associated with the direct fungitoxic property against the pathogen. We conclude that osthol would be an attractive natural compound for practical agronomic use against powdery mildew.

Osthole, a potential antidiabetic agent, alleviates hyperglycemia in db/db mice

Osthole is an agent isolated from Cnidium monnieri (L.) Cusson and Angelica pubescens and has been used to treat several diseases, including metabolic syndromes. To investigate the hypoglycemic effects of osthole in diabetic db/db mice and the underlying mechanisms of these effects by in vitro assay, diabetic db/db mice and cell experiments were utilized to understand its possible effects. Osthole significantly activated both PPARalpha and PPARgamma in a dose-dependent manner based on the results of the transition transfection assay. The activation of PPARalpha and PPARgamma by osthole also resulted in an increase in the expression of PPAR target genes such as PPAR itself, adipose fatty acid-binding protein 2, acyl-CoA synthetases, and carnitine palmitoyltransferase-1A. In vitro results suggested that osthole might be a dual PPARalpha/gamma activator, but its chemical structure differed from that of the thiazolidinedione class of antidiabetic drugs. In addition, osthole markedly activated the AMP-activated protein kinase and its downstream acetyl CoA carboxylase molecules by increasing their phosphorylation levels. Finally, obese diabetic db/db mice were treated with osthole by different administered routes, and osthole was found to markedly reduce blood glucose level. Interestingly, osthole did not reduce the blood insulin or lipid levels, two phenomena that did occur in animals treated with insulin sensitizers like PPAR agonists. These results suggest that osthole can alleviate hyperglycemia and could be potentially developed into a novel drug for treatment of diabetes mellitus.