Temperature Cycling Enables Efficient 13C SABRE-SHEATH Hyperpolarization and Imaging of [1-13C]-Pyruvate.

Molecular metabolic imaging in humans is dominated by positron emission tomography (PET). An emerging nonionizing alternative is hyperpolarized MRI of 13C-pyruvate, which is innocuous and has a central role in metabolism. However, similar to PET, hyperpolarized MRI with dissolution dynamic nuclear polarization (d-DNP) is complex costly, and requires significant infrastructure. In contrast, Signal Amplification By Reversible Exchange (SABRE) is a fast, cheap, and scalable hyperpolarization technique. SABRE in SHield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH) can transfer polarization from parahydrogen to 13C in pyruvate; however, polarization levels remained low relative to d-DNP (1.7% with SABRE-SHEATH versus ≈60% with DNP). Here we introduce a temperature cycling method for SABRE-SHEATH that enables >10% polarization on [1-13C]-pyruvate, sufficient for successful in vivo experiments. First, at lower temperatures, ≈20% polarization is accumulated on SABRE catalyst-bound pyruvate, which is released into free pyruvate at elevated temperatures. A kinetic model of differential equations is developed that explains this effect and characterizes critical relaxation and buildup parameters. With the large polarization, we demonstrate the first 13C pyruvate images with a cryogen-free MRI system operated at 1.5 T, illustrating that inexpensive hyperpolarization methods can be combined with low-cost MRI systems to obtain a broadly available, yet highly sensitive metabolic imaging platform.

Comparative Study of Piper sylvaticum Roxb. Leaves and Stems for Anxiolytic and Antioxidant Properties Through in vivo, in vitro, and in silico Approaches.

Piper sylvaticum Roxb. is traditionally used by the indigenous people of tropical and subtropical countries like Bangladesh, India, and China for relieving the common cold or a variety of chronic diseases, such as asthma, chronic coughing, piles, rheumatic pain, headaches, wounds, tuberculosis, indigestion, and dyspepsia. This study tested anxiolytic and antioxidant activities by in vivo, in vitro, and in silico experiments for the metabolites extracted (methanol) from the leaves and stems of P. sylvaticum (MEPSL and MEPSS). During the anxiolytic evaluation analyzed by elevated plus maze and hole board tests, MEPSL and MEPSS (200 and 400 mg/kg, body weight) exhibited a significant and dose-dependent reduction of anxiety-like behavior in mice. Similarly, mice treated with MEPSL and MEPSS demonstrated dose-dependent increases in locomotion and CNS simulative effects in open field test. In addition, both extracts (MEPSL and MEPSS) also showed moderate antioxidant activities in DPPH scavenging and ferric reducing power assays compared to the standard, ascorbic acid. In parallel, previously isolated bioactive compounds from this plant were documented and subjected to a molecular docking study to correlate them with the pharmacological outcomes. The selected four major phytocompounds displayed favorable binding affinities to potassium channel and xanthine oxidoreductase enzyme targets in molecular docking experiments. Overall, P. sylvaticum is bioactive, as is evident through experimental and computational analysis. Further experiments are necessary to evaluate purified novel compounds for the clinical evaluation.

Ficus cunia Buch.-Ham. ex Roxb. (leaves): An experimental evaluation of the cytotoxicity, thrombolytic, analgesic and neuropharmacological activities of its methanol extract.

Background The aim of this experiment was to evaluate the cytotoxic, thrombolytic, analgesic, sedative-hypnotic and anxiolytic activities of the methanolic extract of Ficus cunia leaves. Methods Primary phytochemical screening was accomplished by using established methods. Cytotoxicity was studied by brine shrimp lethality test, and the thrombolytic assay was conducted through clot lysis method with human blood. The in vivo action was done using mice of both sexes. The analgesic activity was evaluated by acetic acid-induced writhing test and formalin-induced paw licking test. Open field, hole cross and thiopental Na-induced sleeping time test were used to examine the sedative-hypnotic activity, and elevated plus maze (EPM) and hole board test were used to identify the anxiolytic activity. Results The results elicited that the extract contained several phytochemicals such as alkaloid, flavonoid, and tannin. The extract was found to have a median lethal concentration (LC50) value of 55.48 µg/mL in the brine shrimp lethality bioassay. It was also assessed for antithrombotic activity when compared with streptokinase; it has significant (p < 0.001) thrombolytic effect (34.72 ± 1.74%) contrasted with standard streptokinase (67 ± 1.56%). The extract at doses of 200 and 400 mg/kg produced inhibition of 32.58% and 46.63% in acetic acid-induced pain and 45.88 and 61.18% in formalin-induced pain. The sedative and hypnotic activities on the central nervous system of the methanol extract of F. cunia (MEFC) leaves were evaluated. The extract delivered critical sedative impact at the doses of 200 and 400 mg/kg (by oral route) treated with reference to the substance diazepam, and the hypnotic impact was also observed in the case of mice. MEFC at its maximum dose (400 mg/kg) significantly (p < 0.01) increased the time spent in the open arms of the EPM. In the hole board test, there was a dose-dependent (at 200 and 400 mg/kg) and a significant (p < 0.05 and p < 0.01) increase in the number of head pokes in comparison to control. Conclusions The results of the present study gave a helpful baseline in progression for the possible use of MEFC as a cytotoxic, thrombolytic, analgesic, sedative-hypnotic and anxiolytic drug.

In vivo analgesic effect of different extracts of Hopea odorata leaves in mice and in silico molecular docking and ADME/T property analysis of some isolated compounds from this plant.

Background The current study evaluates the analgesic effect of different extracts of Hopea odorata leaves in mice followed by molecular docking and absorption, distribution, metabolism, excretion, and toxicity (ADME/T) analysis of isolated compounds derived from the plant with the COX-1 enzyme. Methods In the present study, the dried leaves of H. odorata were subjected to extraction using methanol, ethanol, and water. In vivo analgesic activity was evaluated by using the acetic acid-induced writhing test and formalin-induced paw licking test, and in silico molecular docking and ADME/T study were performed using Schrödinger Maestro (version 11.1) and online-based tools, respectively, on eight isolated compounds. Results The results showed that the methanolic extract of leaves has highest significant dose-dependent analgesic activity at both 200 and 400 mg/kg followed by ethanolic extract of leaves. Among all the compounds, ampelopsin showed the best docking score of -7.055, ensuring strong binding affinity between the ligand and the receptor, and ADME/T analysis using Web-based tools ensures the compound has not violated Lipinski's rule of five indicating its safety consumption. Conclusions The result confirms the analgesic activity of H. odorata leaves in both in vivo and in silico assays. The data support ampelopsin to be a potent analgesic compound worthy of future clinical trials and its "drug-likeliness".

Assessment of the antioxidant, thrombolytic, analgesic, anti-inflammatory, antidepressant and anxiolytic activities of leaf extracts and fractions of Tetracera sarmentosa (L.) Vahl.

BACKGROUND: The plant under investigation (Tetracera sarmentosa) is a dicotyledonous flowering plant and belongs to the family Dilleniaceae. The goal of our investigation was to determine whether the leaf extracts of this plant held any significant medicinal properties. METHODS: Leaves of T. sarmentosa were extracted with pure ethanol (EETS) and methanol (METS), and then methanol extract fractioned with n-hexane (NHFMETS) and chloroform (CHFMETS). The extracts and fractions were tested for antioxidant activity, which was measured by using qualitative and quantitative procedures. Thrombolytic activity was evaluated by the clot lysis test. Analgesic activity was evaluated employing the acidic acid-induced writhing test, the formalin-induced paw licking test and tail immersion on Swiss albino mice. The anti-inflammatory activity test was studied using the paw edema test. Forced swimming, tail suspension, elevated plus maze and hole board model tests were used to evaluate neuropharmacological activity. RESULTS: All the extracts and fractions possessed antioxidant effects. All the extracts, fractions and streptokinase exhibited significant (p<0.0001) clot lysis. The extracts and fractions produced significant analgesic effects as evaluated by the acetic acid writhing test, the formalin-induced paw licking test and the tail immersion method. Similarly, carrageenan-induced inflammation was significantly antagonized by the treatments. The extracts and fractions also significantly showed neuropharmacological (antidepressant and anxiolytic) effects. CONCLUSIONS: The overall results suggested that this plant deserves further investigation to isolate the active compounds which are responsible for these activities and to establish the mechanism of action.

Antinociceptive Activity of Macaranga denticulata Muell. Arg. (Family: Euphorbiaceae): In Vivo and In Silico Studies.

Background: The present study was conducted to investigate the antinociceptive activity of methanol extract of Macaranga denticulata (Met.MD) in an animal model, followed by molecular docking analysis. Methods: Antinociceptive activity was determined by acetic acid-induced writhing and formalin-induced licking test in mice. Then, molecular docking study was performed to identify compounds having maximum activity against the COX-1 enzyme using Schrödinger Maestro (version 10.1) to determine docking fitness. Results: A preliminary phytochemical analysis of Met.MD revealed that it contained alkaloids, carbohydrates, phenols, flavonoids, tannins, and terpenoids. Met.MD exhibited a dose-dependent and statistically significant antinociceptive activity in the acetic acid and formalin test at the doses of 200 and 400 mg/kg. In addition, our docking study showed that macarangin had the best fitness score of -5.81 with COX-1 enzyme among six major compounds of M. denticulata. Conclusions: Results of the present study confirmed the potential antinociceptive activity of M. denticulata leaf extract in both in vivo and in silico models.

Antidiarrheal and antinociceptive activities of ethanol extract and its chloroform and pet ether fraction of Phrynium imbricatum (Roxb.) leaves in mice.

BACKGROUND: The objective of the study was to evaluate the antidiarrheal and antinociceptive activities of ethanol extract and its chloroform and pet ether fraction of Phrynium imbricatum (Roxb.) leaves in mice. METHODS: In the present study, the dried leaves of P. imbricatum were subjected to extraction with ethanol, and then it was fractioned by chloroform and pet ether solvent. Antidiarrheal effects were tested by using castor oil-induced diarrhea, castor oil-induced enteropooling, and gastrointestinal transit test. Antinociceptive activity was evaluated by using the acetic acid-induced writhing test and formalin-induced paw licking test. RESULTS: The standard drug loperamide (5 mg/kg) showed significant (p<0.001) inhibitory activity against castor oil-induced diarrhea, in which all the examined treatments decreased the frequency of defecation and were found to possess an anti-castor oil-induced enteropooling effect in mice by reducing both weight and volume of intestinal content significantly, and reducing the propulsive movement in castor oil-induced gastrointestinal transit using charcoal meal in mice. The results showed that the ethanol extract of P. imbricatum leaves has significant dose-dependent antinociceptive activity, and among its two different fractions, the pet ether fraction significantly inhibited the abdominal writhing induced by acetic acid and the licking times in formalin test at both phases. CONCLUSIONS: These findings suggest that the plant may be a potential source for the development of a new antinociceptive drug and slightly suitable for diarrhea, as it exhibited lower activity. Our observations resemble previously published data on P. imbricatum leaves.

In vivo analgesic, antipyretic and anti-inflammatory potential of leaf extracts and fractions of Eria javanica.

Background The objective of the study was to evaluate the antinociceptive, antipyretic and anti-inflammatory activities of ethanolic extract, methanolic extract and n-hexane and chloroform-soluble fractions of methanolic extract of Eria javanica leaves in animal model (rat and mice). Methods The anti-nociceptive potentials of the extracts were studied using the acetic acid-induced writhing test in mice and the antipyretic activity was investigated using yeast-induced pyrexia in rats. Anti-inflammatory activity test was done on rats at a dose by using carrageenan-induced paw edema test. Results In acetic acid-induced writhing inhibition study in Swiss albino mice, the crude methanolic extract at 200 mg/kg and 400 mg/kg doses and the n-hexane soluble fraction of crude methanolic extract at 400 mg/kg showed statistically significant activity with 53.21 % (p<0.001), 50.36 % (p<0.001) and 67.86 % (p<0.001) inhibition respectively compared to control. The crude ethanolic extract showed statistically significant antipyretic activity from 1 hours and onwards after administration at doses of 200 mg/kg body weight (p<0.005 at 1st hour and p<0.001 at 2nd, 3rd and 4th hour respectively) and 400 mg/kg body weight (p<0.05 at 1st hour and p<0.001 at 2nd, 3rd and 4th hour respectively). The crude methanolic extract showed statistically significant antipyretic activity from 2 hours and onwards at 400 mg/kg body weight (p<0.05 at 2nd hour and p<0.001 at 3rd and 4th hour respectively) and 200 mg/kg body weight dose showed statistically significant antipyretic activity from 3 hours and onward(p<0.001) in Brewer's yeast-induced pyrexia test in albino Wister rats. In carrageenan-induced rat's paw edema test, crude methanolic extract showed statistically significant anti-inflammatory activity from 2nd hour and onwards. The chloroform-soluble fraction of methanolic extract also showed significant activity from 1st hour onwards. Conclusions This study thereby indicates that leaves of E. javanica possess peripheral analgesic, antipyretic and anti-inflammatory activities and therefore a suitable candidate for further study.

Ethnopharmacological investigation of the aerial part of Phragmites karka (Poaceae).

BACKGROUND: In this ethnopharmacological study, methanolic extract of the aerial plant parts of Phragmites karka (Family: Poaceae) and its petroleum ether and carbon tetrachloride fractions were investigated for bioactivities in Swiss-albino mice, namely, analgesic, central nervous system (CNS) depressant, hypoglycemic, and antidiarrheal activity. METHODS: The cold methanolic extract of the aerial plant parts of Phragmites karka (MEPK) was first prepared, and it was then further fractionated as petroleum ether (PEFMEPK) and carbon tetrachloride (CTFMEPK) fractions. Analgesic activity was performed employing acidic acid-induced writhing test, central analgesic effect by radiant heat tail-flick method. CNS depressant activity was evaluated by phenobarbitone-induced sleeping time test. Hypoglycemic activity was tested by glucose tolerance test (GTT). Antidiarrheal activity was evaluated by castor oil-induced diarrhea method. For all in vivo tests, doses of 200 and 400 mg/kg body weight were used. RESULTS: In the mice model, the MEPK, PEFMEPK, and CTFMEPK fractions showed significant peripheral analgesic activity at a dose of 400 mg/kg body weight with percentage of inhibition of acetic acid-induced writhing 77.67 (p<0.001), 33.50 (p<0.001), and 40.29 (p<0.001), respectively, compared to the standard dichlofenac (60.68%, p<0.001) group. The hypoglycemic properties of MEPK, PEFMEPK, and CTFMEPK extracts were evaluated in normoglycemic mice where the reduction of blood glucose level after 30 min of glucose load were 69.85%, 78.91%, and 72.73%, respectively, and for standard glibenclamide, the reduction was 72.85%. All results were significant (p<0.05). In the case of the CNS depressant activity by phenobarbitone-induced sleeping time test, the crude ME significantly reduced sleep latency by 57.14% and increased the duration of sleep by 63.29% compared to the control, which were comparable to that of standard diazepam (65.71% and 77.62%, respectively). Among all the extract and fractions, methanolic extract showed the maximum antidiarrheal effect. The methanolic extract at 200 mg/kg dose induced a significant decrease in the total number of defecation in 4 h (69.05% of inhibition, p<0.001) and at 400 mg/kg dose showed 76.19% of inhibition (p<0.001). CONCLUSIONS: In light of the available literature, these findings represent the first experimental investigation of biological activities of P. karka in the perspective of their traditional use.

Antioxidant, antidiarrheal, hypoglycemic and thrombolytic activities of organic and aqueous extracts of Hopea odorata leaves and in silico PASS prediction of its isolated compounds.

BACKGROUND: Hopea Odorata, locally known as Telsur (Bangladesh), has some traditional uses as folk medicine. This study aims to investigate the antioxidant, antidiarrheal, hypoglycemic and thrombolytic activities of H. odorata leaf extracts as new therapeutic prospects predicting the activity of some of the isolated compounds of this plant. METHODS: Leaves of Hopea odorata was extracted with pure methanol (MEHO), ethanol (EEHO) and water (AEHO). The extract was tested for antioxidant activity by using reducing power and H2O2 scavenging assay. Antidiarrheal effects were assayed by three standard methods of bioassay: Castor oil-induced diarrhea, Castor oil induced enteropooling and gastrointestinal transit test. Hypoglycemic effect was determined by normoglycemic model of mice. Thrombolytic activity was evaluated by clot lyses test for human and mice blood. In silico PASS prediction was applied for phytoconstituents namely Balanocarpol, Hopeaphenol and Ampelopsin H isolated from this plant. RESULT: Among the all extracts, MEHO exhibited strong antioxidant activity in both reducing power and H2O2 scavenging assay. Phenol content of MEHO was 297.22 ± 0.78 mg/g and flavonol content was 91.53 ± 1.82 mg/g. All the experiment of extracts at dose of 200 and 400 mg/kg and the standard drug loperamide (5 mg/kg) showed significant (p < 0.001) inhibition against castor oil induced diarrhea and castor oil induced enteropooling in mice. There were also significant (p < 0.01) reduction in gastrointestinal motility in the charcoal meal test. Leaf extract showed no significant (P < 0.01) decrease of blood glucose compared to Glibenclamide in normoglycemic mice. Using an in vitro thrombolytic model, MEHO showed the highest and significant clot lysis of human and mice blood compared to Streptokinase. PASS predicted the wide range of antioxidant, free radical scavenger, Nitric oxide scavenger, cardioprotectant, hepatoprotectant, thrombolytic, fibrinolytic, antibacterial, antifungal, anticarcinogenic, anthelmintic and anti-inflammatory activity of examined phytoconstituents. CONCLUSION: These findings suggest that the plant may be a potential source of new antidiarrheal, thrombolytic and antioxidative agents but it is found to have no antidiabetic capability. PASS prediction matched with present study for the extracts. Further study needs to identify the PASS predicted biological actions of the phytoconstituents.

Antithrombotic and cytotoxic activities of four Bangladeshi plants and PASS prediction of their isolated compounds.

BACKGROUND: This study aims to investigate whether tested organic extracts possess antithrombotic properties with minimal or no toxicity and to predict the activity of some of their isolated compounds. METHODS: An in vitro thrombolytic model was used to check the clot lysis effect of four Bangladeshi herbal extracts viz., roots of Curculigo recurvata W.T. Aiton (Satipata), leaf of Amorphophallus bulbifer Roxb. (Olkachu), leaf of Phyllanthus sikkimensis Muell. Arg., and whole plant of Thunbergia grandiflora Roxb. (Nillata) using streptokinase as a positive control and water as a negative control. Cytotoxicity was screened by brine shrimp lethality bioassay using vincristine sulfate as positive control. In silico prediction of activity spectra for substances (PASS) prediction was applied for phytoconstituents, namely, nyasicoside, glucomannan, grandifloric acid, serine, and alanine. RESULTS: Using an in vitro thrombolytic model, C. recurvata, A. bulbifer, P. sikkimensis, and T. grandiflora showed 28.10±1.64%, 42.47±1.96%, 32.86±1.92%, and 25.51±1.67% of clot lysis, respectively. Reference drug streptokinase exhibited 75.00±3.04% clot lysis. Examined herbs showed significant (p<0.001) percentage (%) of clot lysis compared to negative control. In brine shrimp cytotoxic assay, C. recurvata, A. bulbifer, P. sikkimensis, and T. grandiflora showed LC50 values 210.64±3.44, 98.51±1.47, 187.29±2.01, and 386.43±3.02 µg/mL, respectively, with reference to vincristine sulfate (LC50 0.76±0.04). PASS predicted that examined phytoconstituents have a wide range of biological activity. CONCLUSIONS: Through our study it was found that A. bulbifer and P. sikkimensis could be considered as very promising and beneficial thrombolytic agents.

Investigation on hypoglycemic effects of ethanol extract of Alpinia nigra (Gaertn.) in animal model.

BACKGROUND: Our study aims at exploring the hypoglycemic effect, efficacy, and possible mode of action of ethanol extract of Alpinia nigra (EEAN) as an antidiabetic agent in an animal model. METHODS: Oral glucose tolerance test (OGTT) was used to identify primary hypoglycemic effect in mice. Three tests (glucose absorption, sucrose absorption, and disaccharidase activity) were carried out by gut perfusion and six segments studies to assess carbohydrate absorption and glucose utilization. RESULTS: In OGTT, at 400 mg/kg and 800 mg/kg dose of EEAN extract significantly improved oral glucose tolerance among normal mice at 60 min and 90 min with compared to control. Both doses of extract significantly (P < 0.01) reduced blood glucose level and showed the hypoglycemic effect by retarding 11.43% and 20.82% of blood glucose level after 2 h of administration in glucose-induced mice, respectively. In situ perfused rat intestinal model demonstrated reduced glucose absorption at a 500 mg/kg dose. Inhibition of intestinal disaccharidase was also found by the extract. This was confirmed, yet again, via the six segment study. Throughout the length of the gastrointestinal tract, sucrose digestion was found to be inhibited which is also evident in the six segment study. CONCLUSIONS: This study suggests that the EEAN has hypoglycemic effects in a dose-dependent manner by inhibiting intestinal glucose absorption, and these may be effective in the treatment of diabetes. Further study is required to explicate the effect this extract or the active compounds have on the individual glucose transporters and the precise mechanism.

Molecular docking analysis of known flavonoids as duel COX-2 inhibitors in the context of cancer.

Cyclooxygenase-2 (COX-2) catalyzed synthesis of prostaglandin E2 and it associates with tumor growth, infiltration, and metastasis in preclinical experiments. Known inhibitors against COX-2 exhibit toxicity. Therefore, it is of interest to screen natural compounds like flavanoids against COX-2. Molecular docking using 12 known flavanoids against COX-2 by FlexX and of ArgusLab were performed. All compounds showed a favourable binding energy of >-10 KJ/mol in FlexX and > -8 kcal/mol in ArgusLab. However, this data requires in vitro and in vivo verification for further consideration.