Vasorelaxant and Blood Pressure-Lowering Effects of Cnidium monnieri Fruit Ethanol Extract in Sprague Dawley and Spontaneously Hypertensive Rats.

Cnidium monnieri (L.) Cusson, a member of the Apiaceae family, is rich in coumarins, such as imperatorin and osthole. Cnidium monnieri fruit (CM) has a broad range of therapeutic potential that can be used in anti-bacterial, anti-cancer, and sexual dysfunction treatments. However, its efficacy in lowering blood pressure through vasodilation remains unknown. This study aimed to assess the potential therapeutic effect of CM 50% ethanol extract (CME) on hypertension and the mechanism of its vasorelaxant effect. CME (1-30 µg/mL) showed a concentration-dependent vasorelaxation on constricted aortic rings in Sprague Dawley rats induced by phenylephrine via an endothelium-independent mechanism. The vasorelaxant effect of CME was inhibited by blockers of voltage-dependent and Ca2+-activated K+ channels. Additionally, CME inhibited the vascular contraction induced by angiotensin II and CaCl2. The main active compounds of CM, i.e., imperatorin (3-300 µM) and osthole (1-100 µM), showed a concentration-dependent vasorelaxation effect, with half-maximal effective concentration values of 9.14 ± 0.06 and 5.98 ± 0.06 µM, respectively. Orally administered CME significantly reduced the blood pressure of spontaneously hypertensive rats. Our research shows that CME is a promising treatment option for hypertension. However, further studies are required to fully elucidate its therapeutic potential.

International policies and challenges on the legalization of traditional medicine/herbal medicines in the fight against COVID-19.

The coronavirus disease 2019 (COVID-19) has now rapidly spread around the world, causing an outbreak of acute infectious pneumonia. To develop effective and safe therapies for the prevention and treatment of COVID-19 has become the major global public health concern. Traditional medicine (TM)/herbal medicines (HMs) have been used to treat multiple epidemics in human history, which brings hope for the fight against COVID-19 in some areas. For example, in China, India, and South Korea with traditional medication history and theory, the governments issued a series of guidelines to support TM/HMs in the medication of COVID-19. In contrast, other countries e.g. North American and European governments are typically silent on these practices, unless to warn of possible harm and overselling. Such difference is due to the discrepancy in culture, history and philosophical views of health care and medication, as well as unharmonized policies and standards in the regulation and legalization of TM/HMs among different areas. Herein, we reviewed the responses and scientific researches from seven selected countries on the policies and legalization of TM/HMs to treat COVID-19, and also analyzed the major challenges and concerns to utilize the traditional knowledge and resource.

New flavonoids from the roots of Sophora davidii (Franch.) Skeels and their glucose transporter 4 translocation activities.

Five new flavanones, davidones A-E (1-5), one new isoflavonoid, cyclolicoisoflavones A3 (8), together with seven known compounds were isolated from the petroleum ether and the ethyl acetate fractions of the roots of Sophora davidii (Franch.) Skeels. The structures of new compounds were established by 1D and 2D NMR and MS data. The absolute configuration of 1-5 was assigned by NMR calculations and comparing its experimental and calculated ECD spectra. Flavanones were the main active principles responsible for the glucose transporter 4 (GLUT-4) translocation activities of SD-PE and SD-EtOAc. Compounds 1-7 and acacetin (12) promoted GLUT-4 translocation by the range of 1.35-3.00 folds, respectively.

Chemical Constituents from Roots of Sophora davidii (Franch.) Skeels and Their Glucose Transporter 4 Translocation Activities.

Sophora davidii (Franch.) Skeels is a multi-purpose traditional medicine that has long been used for the treatment of various diseases. To discover the potential bioactive composition of S. davidii, a chemical investigation was thus performed. In this research, two new stilbene oligomers, Davidiol E-F (1-2), one new 4-aryl-substituted isoflavan Davidinin A (3), and one new 2-arylbenzofuran dimer, Shandougenine C (4), as well as six known compounds (5-10) were obtained from the ethyl acetate fraction of Sophora davidii (Franch.) Skeels. The structures of new compounds were established by extensive 1D and 2D nuclear magnetic resonance (NMR) spectra with mass spectroscopy data. The absolute configuration of 1-3 was assigned by comparing its experimental and calculated electronic circular dichroism (ECD) spectra. Compounds 1-10 promoted glucose transporter 4 (GLUT-4) translocations by the range of 1.28-2.60 folds, respectively. Compound 9 showed the most potent glucose transporter 4 translocations with 1.60 fold enhancement. The result attained in this study indicated that the separation and characterization of these compounds plays an important role in the research and development of new anti-diabetic drugs and pharmaceutical industry.

Davidones F and G, Two Novel Flavonoids from Sophora davidii (Franch.) Skeels.

An unprecedented novel flavanone davidone F (1) with a seven-membered ring side chain, and a novel flavanonol davidone G (2), along with 11 known flavonoids, were isolated from the ethyl acetate fraction of Sophora davidii (Franch.) Skeels. Their planar structures were established by UV, IR, HRESIMS, 1D and 2D NMR data. The relative configurations of 1 and 2 were determined by calculation of NMR chemical shift values, the absolute configuration of 1 and 2 were assigned by comparing their experimental and calculated electronic circular dichroism (ECD) spectra. Moreover, compounds 1-13 were screened for the translocation activity of glucose transporter 4 (GLUT-4), and the fluorescence intensity was increased to the range of 1.56 and 2.79 folds. Compounds 1 and 2 showed moderate GLUT-4 translocation activity with 1.64 and 1.79 folds enhancement, respectively, at a concentration of 20 µg/mL.

Davidone C Induces the Death of Hepatocellular Carcinoma Cells by Promoting Apoptosis and Autophagy.

Davidone C is a newly discovered flavonoid compound purified from the ethyl acetate-soluble fraction of Sophora davidii (Franch.) Skeels. This study explored the anti-tumor activity of davidone C on hepatocellular carcinoma HepG2 and Bel-7402 cells and its mechanism through MTT method, morphological observation, flow cytometry and Western blotting. The results showed that davidone C significantly inhibited the proliferation of HepG2 and Bel-7402 cells in a time- and dose-dependent manner. The morphological changes of apoptotic cells can be observed under an inverted microscope, such as cell floating, chromosome condensation, apoptotic bodies, and other phenomena. The expressions of Bax, cleaved caspase-9, cleaved caspase-3 and cleaved PARP increased with the increase of dosage while Bcl-2 decreased, suggesting that the apoptotic mechanism might be related to the mitochondrial apoptotic pathway. Moreover, davidone C administration can down-regulate the expression of Grp78, and simultaneously up-regulate the expression of caspase-7 and caspase-12, indicating that the apoptotic mechanism might be related to the ERS pathway. In addition, davidone C can down-regulate the expression of p62, and simultaneously up-regulate the expression of LC3-I and LC3-II with a quantitative dependence, suggesting that the mechanism of apoptosis may be related to the autophagy signal pathway. All these results showed davidone C has potential effects on hepatocellular carcinoma.

Vasorelaxant Effect of Prunus mume (Siebold) Siebold & Zucc. Branch through the Endothelium-Dependent Pathway.

Korean plum (Prunus mume (Siebold) Siebold & Zucc.) has long been used as a health food or herbal medicine in Asia. Previous studies have shown that several plants of the genus Prunus have vasodilatory and antihypertensive effects; we hypothesized that P. mume branches may have a vasorelaxant effect. In this study, we evaluated the effects and action mechanism of 70% ethanol extract of P. mume branch (PMB) on isolated rat aortic rings. Inhibitors such as NG-nitro-l-arginine methyl ester, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, methylene blue, indomethacin, atropine, tetraethylammonium chloride, glibenclamide, 4-aminopyridine and BaCl2 were used to investigate the mechanism of vasodilation responsible for the vascular relaxation. PMB (2-30 µg/mL) induced vasorelaxation in the presence of vascular endothelium, and all inhibitors used in this study affected the degree of relaxation. These results suggest that the vasorelaxant effect of PMB is endothelium-dependent and affects the nitric oxide-cyclic guanosine monophosphate pathway, prostacyclin pathway, muscarinic receptor pathway, and potassium channels. Our study explains that PMB may be another approach to hypertension treatment to reduce the burden of cardiovascular disease.

Prunetin Relaxed Isolated Rat Aortic Rings by Blocking Calcium Channels.

Prunetin, a component of herbal medicines and various foods, such as pea, peach, cherry, and Prunus yedoensis, is a useful pharmacological compound. We previously reported the potent vasorelaxant effect of the bark of P. yedoensis. Therefore, we investigated the vasorelaxant activities of prunetin on isolated rat aortic rings and hypotensive activity on spontaneously hypertensive rats (SHR) in this study. In the present study, prunetin (1⁻30 µg/mL) relaxed isolated rat aortic rings pre-contracted by phenylephrine (PE) in a concentration-dependent manner. Pre-incubation with prunetin (3 and 10 µg/mL) inhibited vasoconstriction induced by the supply of Ca2+ in rat aortic rings pre-contracted with PE or KCl in a Ca2+-free Krebs⁻Henseleit (KH) buffer. Prunetin (10 µg/mL) pre-treatment also inhibited caffeine-induced contraction of aortic rings in a Ca2+-free KH buffer. To investigate the hypotensive effect of prunetin, the systolic blood pressure (SBP) of the SHR was measured by using a tail cuff assay. The SBP of SHR was significantly lower in the prunetin (25 mg/kg)-treated group. These results suggested that prunetin decreased blood pressure and relaxed blood vessels by blocking receptor-operated calcium channels, voltage-dependent calcium channels, and ryanodine receptor channels.

Vasorelaxant effects of Angelica decursiva root on isolated rat aortic rings.

BACKGROUND: Hypertension is one of the most important risk factors for cardiovascular disease (CVD) and a worldwide problem. Despite increases in the development of synthetic drugs for hypertension treatment, the rate of untreated and uncontrolled hypertension remains high. These drugs are effective, but can also cause side effects. Approximately 80% of the world population uses herbal medicines because of their low toxicity and better acceptability by the human body. Therefore, we attempted to identify natural medications for treating hypertension. The 70% ethanol extract of Angelica decursiva root (ADE) shows strong vasorelaxant potential, but no studies have investigated the mechanisms underlying the vasorelaxation effect of A. decursiva. METHODS: Dried root of A. decursiva was identified by DNA sequencing and was extracted once with 1 L 70% ethanol (EtOH) for 3 h in a reflux apparatus at 70 °C. ADE was evaluated for its vasorelaxant effects in rat thoracic aortas. Various inhibitors of ADE-induced vasorelaxation were used. RESULTS: ADE showed vasorelaxant effects on the intact and denuded endothelium of aortic rings pre-contracted with phenylephrine and KCl in Krebs-Henseleit solution. Tetraethylammonium and 4-aminopyridine did not alter ADE-induced vasorelaxation. However, the vasorelaxant effect of ADE was partially inhibited by pre-treatment with glibenclamide an ATP-sensitive K+ channel blocker. Furthermore, ADE concentration-dependently inhibited Ca2+ supplementation-induced vasoconstriction of aortic rings that had been pretreated with phenylephrine or KCl in Ca2+-free Krebs-Henseleit solution. CONCLUSIONS: These results suggest that ADE-induced vasorelaxation occurred in an endothelium-independent manner. The vasorelaxant effects of ADE were correlated with blockade of the KATP channel and inhibition of Ca2+ influx via receptor-operative Ca2+ channels or voltage-dependent Ca2+ channels.

HVC1 ameliorates hyperlipidemia and inflammation in LDLR-/- mice.

BACKGROUND: HVC1 consists of Coptidis Rhizoma (dried rhizome of Coptischinensis), Scutellariae Radix (root of Scutellariabaicalensis), Rhei Rhizoma (rhizome of Rheum officinale), and Pruni Cortex (cortex of Prunusyedoensis Matsum). Although the components are known to be effective in various conditions such as inflammation, hypertension, and hypercholesterolemia, there are no reports of the molecular mechanism of its hypolipidemic effects. METHODS: We investigated the hypolipidemic effect of HVC1 in low-density lipoprotein receptor-deficient (LDLR-/-) mice fed a high-cholesterol diet for 13 weeks. Mice were randomized in to 6 groups: ND (normal diet) group, HCD (high-cholesterol diet) group, and treatment groups fed HCD and treated with simvastatin (10 mg/kg, p.o.) or HVC1 (10, 50, or 250 mg/kg, p.o.). RESULTS: HVC1 regulated the levels of total cholesterol, triglyceride (TG), low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol in mouse serum. In addition, it regulated the transcription level of the peroxisome proliferator-activated receptors (PPARs), sterol regulatory element-binding proteins (SREBP)-2, 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase, lipoprotein lipase (LPL), apolipoprotein B (apo B), liver X receptor (LXR), and inflammatory cytokines (IL-1ß, IL-6, and TNF-α). Furthermore, HVC1 activated 5' adenosine monophosphate-activated protein kinase (AMPK). CONCLUSION: Our results suggest that HVC1 might be effective in preventing high-cholesterol diet-induced hyperlipidemia by regulating the genes involved in cholesterol and lipid metabolism, and inflammatory responses.

Investigation of the mechanisms of Angelica dahurica root extract-induced vasorelaxation in isolated rat aortic rings.

BACKGROUND: The root of Angelica dahurica Bentham et Hooker (Umbelliferae) has been used as a traditional medicine for colds, headache, dizziness, toothache, supraorbital pain, nasal congestion, acne, ulcer, carbuncle, and rheumatism in China, Japan, and Korea. Interestingly, it has been used in the treatment of vascular diseases including hypertension. The aim of this study was to provide pharmacological evidence for the anti-hypertensive effect of A. dahurica by investigating the mechanism underlying its vasorelaxant effect. METHODS: The vasorelaxant effects of a 70% methanol extract of the A. dahurica root (ADE) on rat thoracic aorta and its underlying mechanisms were assessed. Isolated rat aortic rings were suspended in organ chambers containing 10 ml Krebs-Henseleit (K-H) solution and placed between 2 tungsten stirrups and connected to an isometric force transducer. Changes in tension were recorded via isometric transducers connected to a data acquisition system. RESULTS: ADE causes concentration-dependent relaxation in both endothelium-intact and endothelium-denuded aortic rings precontracted with phenylephrine (PE; 1 µM) or potassium (KCl; 60 mM) in K-H solution. And pre-treatment with ADE (1 mg/ml) inhibited calcium-induced vasocontraction of aortic rings induced by PE or KCl. However, ADE pre-treatment did not affect the contraction induced by PE or caffeine in Ca(2+)-free K-H solution. CONCLUSIONS: These results suggested that the ADE has vasorelaxant effect and the vasorelaxant activity is mediated by endothelium-independent pathway that includes the blockade of extracellular calcium influx through the receptor-operated Ca(2+) channel and voltage-dependent calcium channel pathways.

Effect of Ampelopsis Radix on wound healing in scalded rats.

BACKGROUND: Ampelopsis Radix has been used as a traditional Korean medicine for the treatment of burns and scalds. However, there has been no scientific research to date on the wound healing properties of Ampelopsis Radix for scald burns. This study aimed to evaluate the healing effect of Ampelopsis japonica root tuber ethanol extract (AJE) on induced cutaneous scald injury in Sprague Dawley (SD) rats. METHODS: Hot water scalds were induced in SD rats, who were then divided into the following 5 groups; 1) control group without treatment, 2) positive control group with 1% Silver sulfadiazine (SSD), 3) Vaseline group, and groups 4) and 5) that used Vaseline containing 5% and 20% AJE, respectively. The ointment was applied topically to the experimental rats, once daily for 21 days, starting at 24 h post induction of the scald injury. Gross examination, measurement of wound size, and histopathological examination were performed. And quantitative measurement of cytokine levels of tumor necrosis factor alpha (TNF-α), interleukin-10 (IL-10), transforming growth factor beta 1 (TGF-ß1), and vascular endothelial growth factor (VEGF) were performed by enzyme-linked immunosorbent assay. RESULTS: Clinical evaluation showed that the AJE and Vaseline groups, rapidly desquamated scab on day 12 post-scalding; in particular, the 20% AJE group achieved the greatest extent of skin recovery. Sizes of scald wound were significantly lower on days 12, 15, 18, and 21 in the AJE treated groups compared to the control groups. Histopathological evaluation showed a well-organized epithelial layer, angiogenesis, tissue granulation and collagen formation with the exception of inflammatory cells in the AJE-treated groups compared to the control groups on day 14, indicating that tissue regeneration had occurred. AJE treatment decreased TNF-α and increased IL-10 levels on days 2 and 14, indicating the anti-inflammatory action of AJE. The AJE groups also showed a decrease in TGF-ß1 levels on day 7 and VEGF on day 14 in the serum of scald inflicted SD rat model. CONCLUSIONS: These results suggest that AJE possesses scald wound healing activity via accelerating the scald wound repair during the inflammation and proliferative phases of the healing process.

Effects of Eucommia ulmoides extract on longitudinal bone growth rate in adolescent female rats.

Eucommia ulmoides is one of the popular tonic herbs for the treatment of low back pain and bone fracture and is used in Korean medicine to reinforce muscles and bones. This study was performed to investigate the effects of E. ulmoides extract on longitudinal bone growth rate, growth plate height, and the expressions of bone morphogenetic protein 2 (BMP-2) and insulin-like growth factor 1 (IGF-1) in adolescent female rats. In two groups, we administered a twice-daily dosage of E. ulmoides extract (at 30 and 100 mg/kg, respectively) per os over 4 days, and in a control group, we administered vehicle only under the same conditions. Longitudinal bone growth rate in newly synthesized bone was observed using tetracycline labeling. Chondrocyte proliferation in the growth plate was observed using cresyl violet dye. In addition, we analyzed the expressions of BMP-2 and IGF-1 using immunohistochemistry. Eucommia ulmoides extract significantly increased longitudinal bone growth rate and growth plate height in adolescent female rats. In the immunohistochemical study, E. ulmoides markedly increased BMP-2 and IGF-1 expressions in the proliferative and hypertrophic zones. In conclusion, E. ulmoides increased longitudinal bone growth rate by promoting chondrogenesis in the growth plate and the levels of BMP-2 and IGF-1. Eucommia ulmoides could be helpful for increasing bone growth in children who have growth retardation.

Endothelium-Independent Vasorelaxant Effect of Ligusticum jeholense Root and Rhizoma on Rat Thoracic Aorta.

Ligusticum jeholense has been used as the traditional medicine 'Go-Bon' (Chinese name, Gao-ben) in China and Korea. Considering the increased use of medicinal herbs to treat hypertension, in this study, we aimed to investigate the mechanisms of the vasorelaxation effect caused by L. jeholense. We tested the methanol (MeOH) extract of L. jeholense root and rhizoma for vasorelaxant effects; while using an isolated organ-chamber technique, L. jeholense extract (LJE) induced relaxation in the rat aortic rings by stimulating vascular endothelial and smooth muscle cells. LJE showed concentration-dependent relaxant effects on endothelium-intact and endothelium-denuded aortic rings pre-contracted with both phenylephrine (PE) and potassium chloride (KCl) in Krebs-Henseleit (KH) buffer. The vasorelaxant effect of LJE was partly attenuated by pre-treatment with glibenclamide or 4-aminopyridine (4-AP) as K+ channel blockers. Moreover, LJE showed concentration-dependent inhibition of vasoconstriction by Ca2+ supplementation in the aortic rings that were pre-contracted with PE or KCl in Ca2+-free KH buffer. In addition, a combination of LJE and nifedipine, pre-incubated further, decreased PE-induced contractions. The results suggested that LJE-induced vasorelaxation were related to blocking K+ channels and inhibiting entry of extracellular Ca2+ via receptor-operative Ca2+ channels (ROCCs) or voltage-dependent Ca2+ channels (VDCCs).

Sakuranetin as a Potential Regulator of Blood Pressure in Spontaneously Hypertensive Rats by Promoting Vasorelaxation through Calcium Channel Blockade.

Natural compounds, known for diverse pharmacological properties, have attracted attention as potential sources for hypertension treatment. Previous studies have revealed the hypotensive effect and vascular relaxation of prunetin, a natural compound derived from Prunus yedoensis. However, the potential blood pressure-lowering and vasorelaxant effects of sakuranetin, another representative compound found in plants belonging to the genus Prunus, have remained unexplored. We aimed to fill this gap by investigating the hypotensive and vasorelaxant effects of sakuranetin in rats. Results indicated that sakuranetin, particularly in the sakuranetin 20 mg/kg group, led to significant reductions in systolic blood pressure (SBP) and diastolic blood pressure (DBP) by -14.53 ± 5.64% and -19.83 ± 6.56% at 4 h after administration. In the sakuranetin 50 mg/kg group, the SBP and DBP decreased by -13.27 ± 6.86% and -16.62 ± 10.01% at 2 h and by -21.61 ± 4.49% and -30.45 ± 5.21% at 4 h after administration. In addition, we identified the vasorelaxant effects of sakuranetin, attributing its mechanisms to the inhibition of calcium influx and the modulation of angiotensin II. Considering its hypotensive and vasorelaxant effects, sakuranetin could potentially serve as an antihypertensive agent. However, further research is required to evaluate the safety and long-term efficacy.

Blood-Pressure-Lowering and Endothelium-Dependent Vasorelaxant Effects of Nutgall Tree in Rats.

Hypertension is the crucial modifiable risk factor for cardiovascular diseases, and efforts to identify functional foods that are effective for hypertension control are increasing. The nutgall tree (NT, Rhus chinensis Mill.) is used in traditional medicine and food because of its medicinal value. However, the role of NT in hypertension has not been investigated. Therefore, the hypotensive effect of NT leaf ethanol extract (NTE) was investigated in spontaneously hypertensive rats (SHRs). SHRs were allocated to three groups (control, 300, or 1000 mg/kg NTE), and blood pressure was measured before and after oral administration. Systolic and diastolic blood pressure significantly decreased in the NTE 1000 mg/kg group and was the lowest at 2 h after administration (-26.4 ± 10.3, -33.5 ± 9.8%, respectively). Daily NTE administration for five days also resulted in a similar effect. Further, the vasorelaxant effects and related mechanisms were investigated in the aortas of Sprague Dawley rats. NTE showed the dose-dependent blood-vessel-relaxing effect, and its mechanism involves the NO-sGC-cGMP pathway, activation of K+ channels, and reduction in the vasoconstrictive action of angiotensin II. Therefore, our study provides basic data indicating the potential use of NTE as a functional food for high blood pressure.

Vasorelaxant effect of Prunus yedoensis bark.

BACKGROUND: Prunus yedoensis Matsum. is used as traditional medicine-'Yaeng-Pi' or 'Hua-Pi'-in Japan and Korea. However, no studies have examined the pharmacological activities of the P. yedoensis bark. Only the antioxidant and antiviral activities of P. yedoensis fruit and the anti-hyperglycaemic effect of P. yedoensis leaf have been investigated. While studying the antihypertensive effects of several medicinal plants, we found that a methanol extract of P. yedoensis bark (MEPY) had distinct vasorelaxant effects on rat aortic rings. METHODS: The aortic rings were removed from Sprague-Dawley rats and suspended in organ chambers containing 10 ml Krebs-Henseleit solution. The aortic rings were placed between 2 tungsten stirrups and connected to an isometric force transducer. Changes in tension were recorded via isometric transducers connected to a data acquisition system. RESULTS: MEPY relaxed the contraction induced by phenylephrine (PE) both in endothelium-intact and endothelium-denuded aortic rings concentration dependently. However, the vasorelaxant effects of MEPY on endothelium-denuded aortic rings were lower than endothelium-intact aortic rings. The vasorelaxant effects of MEPY on endothelium-intact aortic rings were reduced by pre-treatment with L-NAME, methylene blue, or ODQ. However, pre-treatment with indomethacin, atropine, glibenclamide, tetraethylammonium, or 4-aminopyridine had no affection. In addition, MEPY inhibited the contraction induced by extracellular Ca(2+) in endothelium-denuded rat thoracic aorta rings pre-contracted by PE (1 µM) or KCl (60 mM) in Ca(2+)-free solution. CONCLUSIONS: Our results suggest that MEPY exerts its vasorelaxant effects via the activation of NO formation by means of L-Arg and NO-cGMP pathways and via the blockage of extracellular Ca(2+) channels.

Anti-inflammatory effect of Prunus yedoensis through inhibition of nuclear factor-κB in macrophages.

BACKGROUND: Prunus yedoensis (PY) is a traditional anti-allergy and anti-inflammatory herb medicine used in South Korea. However, until date, little is known regarding its mechanism of action. METHODS: In order to elucidate the mechanism of anti-inflammatory effect of PY, the constituents of PY were analysed by high performance liquid chromatography (HPLC), and nitric oxide (NO) and prostaglandin E2 (PGE2) production were measured enzyme-linked immuno sorbent assay (ELISA). The expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor-κB (NF-κB) were also measured by western blotting in lipopolysaccharide (LPS)-induced RAW 264.7 macrophage cells treated with PY. RESULTS: The results indicate that (50, 100 µg/mL) methanol and ethyl acetate fractionation extracts of PY not only inhibited LPS-mediated NO production and iNOS expression, but also decreased LPS-induced PGE2 production and COX-2 expression. The anti-inflammatory effects of PY were also due to the attenuation of nuclear translocation of NF-κB, as evaluated by the use of anti-p50 on nuclear fractions. LPS-induced nuclear translocation of NF-κB decreased significantly by the methanol extract and ethyl acetate fraction of PY. High performance liquid chromatography (HPLC) analyses revealed that methanol extract and ethyl acetate fraction have similar patterns of retention time and peaks. CONCLUSION: Our results demonstrate that methanol extracts and the ethyl acetate fraction of PY have anti-inflammatory properties, thus emphasizing the potential of PY as a natural health product.

Endothelium-independent vasorelaxation effects of Sigesbeckia glabrescens (Makino) Makino on isolated rat thoracic aorta.

The present study aimed to investigate the vasorelaxant effect of the methanol extract of Sigesbeckia glabrescens (Makino) Makino (MESG) on rat aortic rings and mechanism of action. MESG inhibited both noradrenaline bitartrate (NA)- and potassium chloride (KCl)-induced contraction of endothelium-intact aortic rings in a concentration-dependent manner. Removal of the endothelium did not influence the effect of MESG on NA-precontracted aortic rings. Pretreatment with MESG (250 µg/mL) inhibited calcium chloride-induced vasocontraction of NA- or KCl-precontracted endothelium-denuded aortic rings. It also relaxed phorbol-12-myristate-13-acetate-induced contraction of aortic rings in a concentration-dependent manner. In addition, Bay K8644 (an L-type calcium channel opener) vasocontracted in MESG pretreated aortic rings. On the other hand, the inositol 1,4,5-triphosphate receptor, the ryanodine receptor, the Rho-kinase inhibitor (Y-27632), a soluble guanylyl cyclase blocker (1-H-[1,2,4]-oxadiazolo-[4,3a]-quinoxalin-1-one), and K⁺ channel blockers (glybenclamide, tetraethylammonium, and 4-aminopyridine) did not affect the effect of MESG. These results suggested that the mechanism underlying the vasorelaxant effect of MESG is mediated by endothelium-independent pathways. This specifically refers to blockade of the influx of extracellular Ca²âº via receptor-operative Ca²âº channels and voltage-dependent Ca²âº channels and inhibition of a protein kinase C-mediated cellular pathway.

Terminalia chebula extract protects OGD-R induced PC12 cell death and inhibits lps induced microglia activation.

Terminalia chebula, native to Southeast Asia, is a popular medicinal plant in Ayurveda. It has been previously reported to have strong antioxidant and anti-inflammatory efficacy. In this study, we aimed to investigate if fruit extract from T. chebula might protect neuronal cells against ischemia and related diseases by reduction of oxidative damage and inflammation in rat pheochromocytoma cells (PC12) using in vitro oxygen-glucose deprivation followed by reoxygenation (OGD-R) ischemia and hydrogen peroxide (H2O2) induced cell death. Cell survival was evaluated by a 2-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Free radical scavenging, lipid peroxidation and nitric oxide inhibition were measured by diphenyl-1-picrylhydrazyl (DPPH), thiobarbituric acid (TBA) and Griess reagent, respectively. We found that T. chebula extract: (1) increases the survival of cells subjected to OGD-R by 68%, and H2O2 by 91.4%; (2) scavenges the DPPH free radical by 96% and decreases malondialdehyde (MDA) levels from 237.0 ± 15.2% to 93.7 ± 2.2%; (3) reduces NO production and death rate of microglia cells stimulated by lipopolysaccharide (LPS). These results suggest that T. chebula extract has the potential as a natural herbal medicine, to protect the cells from ischemic damage and the possible mechanism might be the inhibition of oxidative and inflammatory processes.