Antiplatelet Aggregation Activity Research Articles

Platelet Aggregation Activities of Vietnamese Medicinal Plants: Anti-Thrombolytic Potentials?

Blood coagulant, an important physiological process, underlines pathology of various diseases. Thrombosis caused by activated platelets in blood stream can lead to narrowing or blocking the blood flow, which results in stroke or ischemic conditions. The number of human deaths caused by coronary disease or stroke has been increasing rapidly over the last few years in Vietnam. Many anti-thrombosis and anti-platelet aggregation drugs have been discovered and applied in treatment. However, these drugs have many side effects such as bleeding, stomach lesion, etc. Vietnam is a tropical country with plenty of medicinal plants, from which a potential drug for anti-thrombolytic activities can be prepared. Therefore, an overview of Vietnamese medicinal plants with anti-platelet aggregation activities, such as Panax L., Canna, is highly needed for improving the quality of exploiting Vietnamese medicinal resources.
 Keywords
 Anti-thrombosis, Canna, Panax L., platelet aggregation, Vietnamese medicinal plants.
 References
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Antiplatelet Aggregation, Cardiotonic, Anti-Inflammatory, Antioxidant, and Calcium Channel Antagonistic Potentials of Nepeta ruderalis Buch.

The objective of this study was to authenticate the ethnobotanical claims of the Nepeta ruderalis Buch.-Ham. (N. ruderalis) extract in the traditional system of medicine. Crude extract was prepared via a simple maceration process. DPPH free radical scavenging and carrageenan-induced rat paw edema models were used to monitor antioxidant and anti-inflammatory responses of the N. ruderalis extract. Furthermore, it was tested for antiplatelet aggregation, cardioprotective, and calcium channel antagonistic activities via standard documented protocols. The N. ruderalis extract exhibited 80.82% antioxidant activity (IC50 = 207.51 ± 4.36 μg) while the anti-inflammatory response was significant (p < 0.05 to p < 0.01) at 50 mg/kg (45.58%) and 100 mg/kg (60.90%) doses. Moreover, it was found to inhibit platelet aggregation (IC50 = 1.06 and 0.91 mg/mL) and, in addition, to increase the force of contraction at the concentration of 3.0-10 mg/mL with a decrease in the heart rate on isolated paired atria (EC50 = 11.78 mg/mL). Relaxant activity was observed on the isolated rabbit jejunum (EC50 = 0.96 mg/mL) and trachea (EC50 = 0.89 mg/mL). However, in a cumulative way, an 80-millimolar potassium-induced contraction was evaluated (EC50 = 1.31 mg/mL). The N. ruderalis extract exhibited antioxidant, anti-inflammatory, platelet aggregating, cardiotonic, and calcium channel antagonistic activities, therefore proving scientifically its effectiveness in the traditional system of medicine.

Anti-inflammatory, Antiplatelet Aggregation, and Antiangiogenesis Polyketides from Epicoccum sorghinum: Toward an Understating of Its Biological Activities and Potential Applications.

The ethyl acetate extract of an endophyte Epicoccum sorghinum exhibited anti-inflammatory activity at a concentration of <10 μg/mL. By bioassay-guided fractionation, one new compound, named epicorepoxydon A (1), and one unusual bioactive compound, 6-(hydroxymethyl)benzene-1,2,4-triol (6), together with six known compounds, were isolated from E. sorghinum. The structures of all isolates were established by spectroscopic analyses. The relative configuration of 1 was deduced by the NOESY spectrum and its absolute configuration was determined by X-ray single-crystal analysis. The biological activities of all isolates were evaluated using four types of bioassays including cytotoxicity, anti-inflammatory, antiplatelet aggregation, and antiangiogenesis activities. Compounds 4 and 6 showed potent anti-inflammatory activity, compound 2 possessed potent antiplatelet aggregation and antiangiogenesis activities, and compound 6 demonstrated antiangiogenesis activity. This fungal species can cause a human hemorrhagic disorder known as onyalai. In this study, we identified the active components with antiplatelet aggregation and antiangiogenesis activities, which may be related to the hemorrhagic disorder caused by this fungus. Moreover, we proposed a biosynthetic pathway of the isolated polyketide secondary metabolites and investigated their structure–activity relationship (SAR). Our results suggested that E. sorghinum is a potent source of biologically active compounds that can be developed as antiplatelet aggregation and anti-inflammatory agents.

Synthesis of 3,15-Disuccinate-12-Coumarin Substituted Andrographolide Derivatives and Their Antiplatelet Aggregation Activities In Vitro

In order to develop a series of novel compounds with antiplatelet aggregation activities, 3,15-disuccinate-12-coumarin substituted derivatives were designed and synthesized based on the natural product andrographolide. In vitro antiplatelet aggregation activities were evaluated by the turbidimetric method with thrombin, adenosine diphosphate (ADP), arachidonic acid (AA), and collagen as inducers. The biological evaluation revealed that compound 11k showed significant inhibition activity for thrombin, AA, and collagen-induced platelet aggregation at the same time and exhibited a dose-dependent behavior. Compound 11c showed the highest antiplatelet aggregation activity induced by ADP. Most of the derivatives had no significant cytotoxicity. Therefore, our work proved that 3,15-disuccinate-12-coumarin substituted andrographolide derivatives had the potential to become a novel candidate structure for antiplatelet aggregation and deserved further study.

Novel factor Xa inhibitor, maslinic acid, with antiplatelet aggregation activity.

As antithrombotic effects of maslinic acid (MA) have not yet been studied, MA-mediated downregulation of coagulation factor Xa (FXa) and platelet aggregation was studied. We show that MA inhibited the enzymatic activity of FXa and platelet aggregation, induced by adenosine diphosphate (ADP) and a thromboxane A2 (TXA2 ) analog, U46619 with a similar antithrombotic efficacy to rivaroxaban, a direct FXa inhibitor used as a positive control. Mechanistically, MA suppressed U46619- or ADP-induced phosphorylation of myristoylated alanine-rich C kinase substrate, and the expression of P-selectin, and activated PAC-1 in platelets. MA increased generation of nitric oxide, but downregulated excessive secretion of endothelin-1 in ADP- or U46619-treated human umbilical vein endothelial cells. In arterial and pulmonary thrombosis mouse model, MA showed prominent anticoagulant and antithrombotic effects. Our data suggest MA as a candidate molecule for a new class of drugs targeting anti-FXa and antiplatelet.

Analysis of quinary therapy targeting multiple cardiovascular diseases using UV spectrophotometry and chemometric tools.

Herein, UV spectrophotometry assisted by multivariate chemometric analysis have been presented for quantitative determination of complex quinary therapy containing atenolol, ramipril, hydrochlorothiazide, simvastatin and aspirin without any prior separation. Such combination is very useful for treating various cardiovascular diseases (CVD) including high blood pressure, hypercholesterolemia in addition to its antiplatelet aggregating activity. Calibration (15 samples) and validation (10 samples) sets were prepared of different concentrations for these drugs via implementing partial factorial experimental design. The zero order UV spectra of these sets were recorded and then subjected for further chemometric analysis. Partial least square (PLS) with/without variable selection procedure i.e. genetic algorithm (GA) were employed to untangle the UV spectral overlapping of these mixtures. The performance of these chemometric techniques were compared in terms of accuracy and predictive abilities using cross-validation and external validation methods. It was found that PLS provides good recoveries with prompt predictive ability albeit GA-PLS exhibited better analytical performance owing to its capability to remove redundant variables i.e. the number of absorbance variables had been reduced to about 19-28%. The developed methods allowed reliable determination of such complex therapy in its laboratory prepared mixtures and pharmaceutical preparation within comparable results to those reported by HPLC method, posing these chemometric methods as valuable and indispensable analytical tools in in-process testing and quality control analysis of many pharmaceutical compounds targeting CVD.

The in vitro bioavailability of anti-platelet peptides in collagen hydrolysate from silver carp (Hypophthalmichthys molitrix) skin.

Previous animal experiments indicated collagen hydrolysates (CHs) intake decreased platelet release indicators in plasma and highlight potential applications as healthcare supplements to combat cardiovascular disease. The oligopeptides (GPR, GPRG, and GPRGP) have anti-platelet activities. However, it is still unclear whether they are bioactive compounds in CHs from silver carp skin. We investigated the bioavailability of oligopeptides using simulated gastrointestinal digestion and Caco-2 model. Anti-thrombotic activities, in vitro platelet aggregation and formation of platelet thrombus, were evaluated. They resisted gastrointestinal digestion and could be absorbed by Caco-2. Oligopeptides inhibited platelet aggregation induced by adenosine diphosphate and thrombin with IC50 of 0.160, 0.283, 0.251mg/ml and 0.714, 1.008, 0.917mg/ml for GPR, GPRG, and GPRGP, respectively. Oligopeptides prolonged the time of platelet thrombus and inhibited coagulation cascades, but CHs performed no bleeding side effect. These results confirmed that oligopeptides could be used as bioactive compounds of dietary supplements for pre-thrombotic to prevent thrombosis. PRACTICAL APPLICATIONS: Oligopeptides, GPR, GPRG, and GPRGP, derived from silver carp (Hypophthalmichthys molitrix) skin collagen, performed anti-thrombotic activities from their anti-platelet aggregation and anticoagulation activities. But the collagen hydrolysates containing these peptides had no side effect of bleeding in the mice model. Furthermore, this study investigated the bioavailability of these three bioactive peptides by the Caco-2 cells model. Thus, oligopeptides GPR, GPRG, and GPRGP are a potential index of bioactive compounds in the preparation of anti-thrombotic functional foods or healthcare supplements for people at the pre-thrombotic state.

Synthesis and antithrombotic activity of 1-benzyl-N'-benzylidenepiperidine-3-carbohydrazide derivatives.

: Platelet aggregation inhibition and interfering with clot formation are essential tools for antithrombotic therapy and there is a need for discovering new antithrombotic agents. In this study, we synthesized a series of benzylidenepiperidine-3-carbohydrazide derivatives (1f-11f), bearing various selected substituents on both the piperidine ring nitrogen and the hydrazide nitrogen. The synthesized compounds were characterized by FTIR, HNMR spectroscopic techniques, CHN/O elemental analysis and electrospray ionization mass spectra. All new 1-benzyl-N'-benzylidenepiperidine-3-carbohydrazides were evaluated for their antiplatelet aggregation activities (against platelet aggregation induced by AA, ADP and collagen separately) and anticoagulant activities [protrombin time (PT) and partial thromboplastin time (PTT)]. Antiplatelet aggregation activity of the new derivatives was measured using human plasma on an APACT 4004 aggregometer. All the compounds were mainly effective on ADP pathway of platelet aggregation compared with collagen and AA pathways. The most potent compound on platelet aggregation induced by ADP is compound 2f with 87% aggregation inhibition activity at 0.5 mmol/l concentration. The synthesized compounds were further investigated for their anticoagulant action via the two PT and PTT models. They all showed higher PT and PTT values compared with the blank control sample. The most potent compounds are 5f, 6f, 7f and 1f. All compounds were obtained in good yield and further evaluated for their antiplatelet and anticoagulant activity.

Pharmacological activities of Oyster mushroom (Pleurotus ostreatus)

In this review paper, different characteristics especially medicinal values of Oyster mushroom were described. As a mycological expression, mushrooms are a fruiting body of macro fungi i.e. Basidiomycota that represents only a short reproductive stage in their life cycle. They have a long association with humankind, and provide profound biological and economic impacts. Starting from ancient times, mushrooms are consumed by man with delicacy, due to their good taste and pleasing flavor. Pleurotus ostreatus is an edible mushroom with high nutritional values and biomedical importance's, since it contains a large number of bioactive components that cause development of its therapeutic functions. The bioactive components that are present in Pleurotus ostreatus mushroom comprise: polysaccharides, lipopolysaccharides, proteins, peptides, glycoproteins, nucleosides, tri-terpenoids, lectins, lipids and their derivatives, in addition of its vital medicinal components beneficial for the human health. Moreover, Pleurotus ostreatus possess several medicinal properties including; anti-arthritic, antitumor, immune-modulatory, antioxidant, anticancer, anti-inflammatory, antigenotoxic, hypo cholesterolaemic, anti-hyperglycaemic, anti-hypertensive, antiplatelet aggregating, antiviral and antimicrobial activities.

IN VITRO ANTI-PLATELET AGGREGATION ACTIVITY OF HYDROXYPROPYL CELLULOSE–CYSTEAMINE BASED NANOPARTICLES CONTAINING CRUDE BROMELAIN

Objective: The aim of the present study was to formulate bromelain into nanoparticles in order to improve its stability and activity.&#x0D; Methods: Crude bromelain was prepared by protein precipitation from the pineapple stem juice using ammonium sulphate at the concentration of 60% (w/v). Nanoparticles containing crude bromelain were generated using the ionic gelation method with hydroxypropyl cellulose–cysteamine (HPC-cysteamine) conjugate as a matrix. Crude bromelain was then added to the HPC-cysteamine solution for ionic interaction to construct the nanoparticles, which were then analyzed for their particle size and zeta potential. The resulting nanoparticles were mixed with adenosine diphosphate (ADP) to perform anti-platelet aggregation.&#x0D; Results: The nanoparticle had 928.3 nm in particle size and-7.25 mV in zeta potential. Anti-platelet activity of crude bromelain and the nanoparticles were determined with modification of light transmission aggregometry (LTA), in which ADP was used to induce an aggregation while a spectrophotometer UV-Vis was used to measure the absorbance at the wavelength of 600 nm. The result showed that crude bromelain and the nanoparticles rendered percentage inhibition of 8.00±1.17% and 48.56±11.19%, respectively.&#x0D; Conclusion: Based on the result of a one-way analysis of variance (ANOVA), it was concluded that there was a significant difference in percentage inhibition between the two samples. The nanoparticles demonstrated a better anti-platelet aggregation activity compared to crude bromelain.

Determination of protein binding for novel 2-(2-hydroxypropanamido)-5-trifluoromethyl benzoic acid enantiomers to rats, dogs, and humans plasma by UPLC-MS/MS.

R-/S-2-(2-hydroxypropanamido)-5-trifluoromethyl benzoic acid (R-/S-HFBA) is a novel COX inhibitor with remarkable anti-inflammatory and antiplatelet aggregation activities, but no gastrointestinal toxicity. In our previous study, the different pharmacokinetic profiles of the two enantiomers in rats were observed after administration of R-HFBA and S-HFBA. Stereoselective protein binding of the two enantiomers may be a reason for the different pharmacokinetic behaviors. In this study, we developed and validated an UPLC-MS/MS method for determining stereoselective binding of HFBA enantiomers to rat, dog, and human plasma in vitro. Chromatographic separation was achieved by gradient elution with a flow rate of 0.4 mL/min. MS/MS detection was operated in positive electrospray using multiple reaction monitoring (MRM) mode. The method was proved to be linear over the concentration range of 0.005 to 10 μg/mL with a lower limit of quantification of 0.005 μg/mL. The developed method was successfully employed to the plasma protein binding study of HFBA enantiomers. Equilibrium dialysis method was applied to assess drug-plasma protein interactions. The results showed that the enantiomers were both extensively bound to three species plasma and protein binding of R-/S-HFBA was concentration dependent. R-HFBA and S-HFBA showed significant species difference among rat, dog, and human plasma and stereoselective plasma protein binding.

A new bilobalide isomer and two cis-coumaroylated flavonol glycosides from Ginkgo biloba leaves

A new bilobalide isomer (1), together with two flavonol glycosides (2, 3), have been isolated and elucidated from the extract of Ginkgo biloba leaves. Significantly, 1 was a new sesquiterpene lactone with two lactone ring groups, both 2 and 3 were two flavonol glycosides with a same cis-coumaroylated fragment. Their chemical structures were elucidated by NMR and MS spectroscopic date and the absolute configuration of 1 was specific established by Cu-Kα X-ray crystallographic analyses. However, 1–3 showed no obvious anti-platelet aggregation activity.

VITPOR AI, A Coagulation Factor XIIa Inhibitor from Porphyra yezoensis: In Vivo Mode of Action and Assessment of Platelet Function Analysis

Thrombosis represents as the prime contributor to the burden of diseases, worldwide. Conventional anticoagulants for thrombosis therapy have a common bleeding side effect. Bioactive peptides are studied to be an effective alternative for currently available therapeutic drugs. In this study, VITPOR AI peptide, a previously reported coagulation FXIIa inhibitor from Nori (Porphyra yezoensis), was assessed for its inhibitory activity against FXIIa and its in vivo mode of action. In vivo efficacy as well as the antithrombotic property of the peptide was evaluated in mice model by ex vivo activated Partial Thromboplastin Time assay, tail transection model and whole blood clotting time. The enzyme kinetics was studied using chromogenic substrate assay. The kinetic behaviour of VITPOR AI showed that the peptide is a competitive inhibitor of FXIIa. Peptide showed significant inhibition of platelet adhesion and aggregation. VITPOR AI exhibited significant antithrombotic activity. Furthermore, ex vivo activated Partial Thromboplastin Time assay revealed that VITPOR AI exhibited potent anticoagulant activity in vivo. Tail bleeding assay revealed that the peptide did not prolong bleeding time in mice even at a higher dose of 5 mg/kg. Cytotoxicity studies of the peptide against human blood leukocytes indicated the safety of the peptide. VITPOR AI could be prospected as a potent anticoagulant with Factor XIIa inhibition, antiplatelet aggregation and antithrombotic activity. It was also studied to have no bleeding side effect.

Synthesis, oral bioavailability evaluation and antiplatelet aggregation activity of three derivatives of 3,4‑dihydroxyacetophenone

3,4‑Dihydroxyacetophenone (DHAP) exerts therapeutic effects on cardiovascular disease and pulmonary heart disease. However, it is not utilized as a clinical drug due to its rapid metabolism, short‑acting effect and low oral bioavailability. In the present study, three derivatives of DHAP, including 4‑acetyl‑1,2‑phenylene dipropionate (APDP), 1‑(3‑hydroxy‑4‑phenoxy‑phenyl)‑ethanone (HPPE) and a polymer derivative, PEG‑DHAP, were synthesized via the esterification or etherification of hydroxyls at C3 and C4, which are the prime metabolism sites of DHAP. The physicochemical properties, pharmacokinetic and antiplatelet aggregation activities of these derivatives were measured to determine whether they can improve the defects of DHAP. The results revealed that APDP and HPPE exhibited markedly lower water solubility and higher oil‑water partition coefficients compared to DHAP. APDP rapidly transformed into DHAP invivo and invitro, indicating that there were no significant differences in the values of mean residence time invivo [MRT (0‑t)], half‑life [t1/2], oral bioavailability and antiplatelet aggregation activity invivo and invitro between the two agents. HPPE partially released DHAP for a period of time following oral administration. PEG‑DHAP contained 12.47% DHAP dispersed into nanoparticles with a mean particle size of 260.90nm. This was administered in aqueous solution and was demonstrated to release DHAP slowly following oral administration. These two derivatives significantly prolonged the invivo acting time and increased the oral bioavailability of DHAP: Following intragastric administration, their MRT (0‑t) and t1/2 values were 3.55‑11.47‑ and 6.63‑11.25‑fold higher compared with those of DHAP, respectively. Additionally, their relative bioavailability was 394.79 and 331.88%, respectively, and they exhibited longer acting times of significant antiplatelet aggregation activity. The results of the present study may thus provide a reference for the development of DHAP as an oral drug. Furthermore, the results if this study may prove to be useful to researchers addressing the issue of the poor bioavailability of phenolic drugs.

Apyrase with anti-platelet aggregation activity from the nymph of the camel tick Hyalomma dromedarii.

Apyrase is one of the essential platelet aggregation inhibitors in hematophagous arthropods due to its ability to hydrolyze ATP and ADP molecules. Here, an apyrase (TNapyrase) with antiplatelet aggregation activity was purified and characterized from the nymphs of the camel tick Hyalomma dromedarii through anion exchange and gel filtration columns. The homogeneity of TNapyrase was confirmed by native-PAGE, SDS-PAGE as well as with isoelectric focusing. Purified TNapyrase had a molecular mass of 25kDa and a monomer structure. TNapyrase hydrolyzed various nucleotides in the order of ATP > PPi > ADP > UDP > 6GP. The Km value was 1.25mM ATP and its optimum activity reached at pH 8.4. The influence of various ions on TNapyrase activity showed that FeCl2, FeCl3 and ZnCl2 are activators of TNapyrase. EDTA inhibited TNapyrase activity competitively with a single binding site on the molecule and Ki value of 2mM. Finally, TNapyrase caused 70% inhibition of ADP-stimulated platelets aggregation and is a possible target for antibodies in future tick vaccine studies.

PLECTRANTHUS AMBOINICUS: A REVIEW ON ITS PHARMACOLOGICAL AND, PHARMACOGNOSTICAL STUDIES.

In this review, information regarding phytochemistry, traditional uses, medicinal uses, side effects and future perspectives of Plectranthus amboinicus are given. Plectranthus amboinicus has been used in herbal medicines for the treatment of various disorders like asthma, flu, eczema and cardiovascular disorders. The plant possesses medicinal properties (such as antimicrobial activity, antifungal activity, anti-inflammatory activity, antidiabetic activity, anxiolytic activity, antineoplastic, analgesic, antimalarial, anti-biofilm efficacy, diuretic, wound healing activity, skincare, respiratory disorders, anti-platelet aggregation activity) due to the presence of various important constituents or secondary metabolites such as flavonoids, glycosides, phenols, tannins, and steroids, which have been identified via various spectroscopic methods. The different parts of the plant have used to prepare medicines. Owing to the presence of various important constituents, this plant can be used for medicines without side effects.

Exploring stereoselective excretion and metabolism studies of novel 2-(2-hydroxypropanamido)-5-trifluoromethyl benzoic acid enantiomers.

R-/S-2-(2-Hydroxypropanamido)-5-trifluoromethyl benzoic acid (R-/S-HFBA), as a novel COX inhibitor, was firstly reported to have remarkable anti-inflammatory and antiplatelet aggregation activities by our group. In our previous study, stereoselective differences in pharmacokinetics were found between HFBA enantiomers after oral and intravenous administration of each enantiomer to rats. The discrepancies might be associated with the excretion and metabolism of the two enantiomers. In this research, an UHPLC-MS/MS method was established and validated for quantification of R-/S-HFBA in rats urine, feces and bile samples in excretion study. Moreover, an ultra high performance liquid chromatography coupled with Fourier transform ion cyclotron resonance mass spectrometry (UHPLC-FT-ICR-MS) method was employed to understand the metabolism of R-/S-HFBA in rats. Results showed that the total cumulative excretion of R-/S-HFBA in three routes were 65.8% and 58.5% of the dose, respectively. The urinary excretion of R-/S-HFBA was the main route, which accounted for 40.2% and 31.7% respectively; the cumulative biliary excretion of R-/S-HFBA were 11.3% and 7.4%; the cumulative amounts of R-/S-HFBA excreted directly via feces without absorption from the gastrointestinal tract were 14.3% and 19.4%, respectively. R-/S-HFBA existed stereoselective discrepancy in excretion. In addition, 8 metabolites of S-HFBA were detected and tentatively identified including glucuronidation, glycine and N-acetyl conjugation while R-HFBA existed 7 metabolites without glycine conjugation. Formation of metabolites of R-/S-HFBA also exhibited stereoselectivity. In summary, these new findings on excretion and metabolism of R-/S-HFBA provided valuable information for stereoselective pharmacokinetics and were greatly helpful for further investigation, such as safety and mechanism of action.

川芎嗪衍生物合成及抗血小板聚集活性研究

川芎嗪衍生物合成及抗血小板聚集活性研究

Design, synthesis, and biological evaluation of 4-methoxy-3-arylamido-N-(substitutedphenyl)benzamide derivatives as potential antiplatelet agents.

A series of 4-methoxy-3-arylamido-N-(substitutedphenyl)benzamides 6a-u were designed according to the splicing principle of structural design in the medicinal chemistry theory and were synthesized in five steps: nitration, acylation, ammoniation, reduction, and secondary ammoniation. The structures of the target compounds were characterized and verified by infrared, 1 H nuclear magnetic resonance (NMR), 13 C NMR, and electron spray ionization spectroscopy. Their in vitro antiplatelet aggregation activities induced by adenosine diphosphate (ADP) or arachidonic acid (AA) were assessed by Born's method. The biological evaluation revealed that all compounds exhibited certain levels of activities in both of the antiplatelet aggregation assays; compounds 6c (IC50 = 3.84 μM) and 6f (IC50 = 3.12 μM) displayed the strongest antiplatelet aggregation activities in the ADP-induced and AA-induced assay, separately. Moreover, compounds that had stronger activities were chosen for cell toxicity testing via the cell counting kit-8 assay. The results indicated that none of the compounds had obvious cell toxicity against L929 cells at the doses of 10 and 20 μM. It is worth pointing out that compound 6c showed the highest antiplatelet activity and the lowest cell toxicity. In general, 4-methoxy-3-arylamido-N-(substitutedphenyl)benzamides have the potential to become a kind of safer and more effective antiplatelet agents.

Role of Whole Plant Extract of Nelumbo nucifera Gaertn in the Treatment of Thrombolysis.

This study aims to find out the components responsible for the antithrombotic activity of Nelumbo nucifera. Petroleum ether, chloroform and hydroalcoholic extracts of whole plant of Nelumbo nucifera (Lotus) were prepared and assessed for its thrombolytic, anti-platelet aggregation activity and bleeding time. The extracts were further analyzed through HPTLC and GC-MS. Statistical analysis was conducted through ANOVA trailed by Tukey's multiple comparison test test. Hydroalcoholic extract showed the highest activity at the concentration of 400µg/ml in thrombolytic assay (42.03 ± 5.76), anti-platelet aggregation assay (57.93 ± 1.68) and bleeding time (70.17 ± 2.16) in comparison to clopodigrel (33.76 ± 3.43), aspirin (66.55 ± 1.86) and aspirin (93.85 ± 2.75) at the concentration of 100 µg/ml respectively. 25 peaks were identified through GC-MS, out of which, ferulic acid (14.2µ/g) and quercetin (5.4 µ/g) are active chemical compounds. HPTLC showed different chromatograms in hydroalcoholic extracts like (1) chlorogenic, (2) quercetin, (3) benzoic acid, (4) caffeic acid, (5) ferulic acid, (6) kaempferol, and (7) gallic acid. Based on these findings, flavonoids present in hydroalcoholic extract may be developed into a drug for clinical application for the treatment of thrombosis in patients.