Bioactivity-Guided Fractionation and Identification of Antidiabetic Compound of Syzygium polyanthum (Wight.)'s Leaf Extract in Streptozotocin-Induced Diabetic Rat Model.

(1) Background: An earlier study on the hypoglycemic activity of S. polyanthum (Wight.) leaf methanol extract identified squalene as the major chemical compound. The present study was conducted to assess the hypoglycemic effect of fractions and subfractions of the methanol extract of S. polyanthum compared to the squalene using a bioassay-guided in vivo study. (2) Methods: The methanol extract was fractionated using the liquid−liquid fractionation method. Streptozotocin-induced type 1 diabetic rat was used to study the hypoglycemic effect. (3) Results: The findings showed that chloroform fraction significantly (p < 0.05) lowered blood glucose levels of diabetic rats as compared to the control. Further fractionation of chloroform fraction yielded subfraction-1 and -2, whereby subfraction-1 exhibited a higher blood-glucose-lowering effect. The lipid profile test showed that the total cholesterol level of subfraction-1 and squalene-treated groups decreased significantly (p < 0.05). An immunohistochemistry study revealed that none of the treatments regenerated pancreatic ß-cells. Gas chromatography−mass spectrophotometer analysis identified the presence of squalene in the active methanol extract, chloroform fraction, and subfraction-1. In silico analysis revealed a higher affinity of squalene against protein receptors that control lipid metabolism than metformin. (4) Conclusions: Data obtained from the present work suggested the crude methanol extract exerted the highest hypoglycemic effect compared to fraction, subfraction, and squalene, confirming synergistic effect may be responsible for the hypoglycemic activity of S. polyanthum.

Safety assessment of the ethanolic extract of Gongronema latifolium Benth. leaves: a 90-day oral toxicity study in Sprague Dawley rats.

BACKGROUND: The leaves of Gongronema latifolium Benth. have long been recognized traditionally as a remedy for a variety of ailments in Africa. This study was conducted to evaluate the safety profile of the ethanolic extract of G. latifolium (GLES) leaves through a repeated dose 90-day oral toxicity study in male and female of Sprague Dawley rats. METHODS: GLES was orally administered at doses of 250, 500 and 1000 mg/kg/day consecutively for 90 days. RESULTS: No behavioral or physiological changes and mortality were observed. GLES did not have a marked impact on general hematological parameters and did not precipitate nephrotoxicity. However, compared to the control, serum triglycerides, total cholesterol and low-density lipoprotein levels were lower and white adipose tissue paired retroperitoneal fat depots were depleted in male rats treated with GLES3 by the end of the experiment. The liver was significantly enlarged in GLES-treated rats of both sexes. Negative gender-specific alterations were observed with the highest dose. Adverse risk was evident in the female rats mainly due to marked body weight gain and cerebrum weight reduction. CONCLUSION: Further research is needed to reach more specific conclusions about to the safety of ingesting high doses of GLES for long periods of time.

Vasorelaxant activities and the underlying pharmacological mechanisms of Gynura procumbens Merr. leaf extracts on rat thoracic aorta.

Previous studies have investigated the cardiovascular activity of Gynura procumbens Merr. single-solvent extracts. The objective of this study was to evaluate the in vitro vasorelaxant properties and the underlying pharmacological mechanisms of serial extracts and fractions of Gynura procumbens (GP). The leaves of GP were serially extracted with petroleum ether, chloroform, methanol and water using the maceration method. Suspended aortic ring preparations were pre-contracted with phenylephrine (PE 1 µM), followed by cumulative addition of GP extracts (0.25-3 mg/mL). The petroleum ether extract (GPPE) was the most potent among the four extracts. Pre-incubation of endothelium-intact aorta with atropine (1 µM), indomethacin (10 µM), methylene blue (10 µM), propranolol (1 µM) and potassium channel blockers such as TEA (1 µM), glibenclamide (10 µM), 4-aminopyridine (1 µM) and barium chloride (10 mM) had no effect on GPPE-induced vasorelaxation. The vasorelaxant effect of GPPE was partly diminished by pretreatment of aortic rings preparations with L-NAME (10 µM) and even more so in endothelium-denuded aortic rings, indicating a minimal involvement of endothelium-dependent pathway in GPPE-induced vasorelaxation. The calcium-induced vasocontractions were antagonized significantly and concentration-dependently by GPPE in calcium free and high potassium medium. These results illustrate that Ca2+ antagonizing actions of GPPE in rat isolated aorta are comparable to that of verapamil and may be mainly responsible for its vasodilation effect. The antioxidant activity of GPPE supports its vasorelaxant effect by attenuating the production of deleterious free radicals and reactive oxygen species in the vasculature.

Correction to: Standardized extract of Ficus deltoidea stimulates insulin secretion and blocks hepatic glucose production by regulating the expression of glucose-metabolic genes in streptozitocin-induced diabetic rats.

After the publication of this article [1] it came to our attention that one author, Boon Yin Khoo, was erroneously omitted from the authorship list.

Acute and subchronic toxicity studies of methanol extract of Polygonum minus leaves in Sprague Dawley rats.

Medicinal plant preparations may contain high levels of toxic chemical constituents to potentially cause serious harm to animals and/or humans. Thus, toxicity studies are important to assess the toxic effects of plant derived products. Polygonum minus is used traditionally for different ailments in Southeast Asia. This study was conducted to establish the acute and subchronic toxicity profile of the methanol extract of P. minus leaves. The acute toxicity study showed that the methanol extract of P. minus is safe even at the highest dose tested of 2000 mg/kg in female Sprague Dawley rats. There were no behavioural or physiological changes and gross pathological abnormalities observed. The subchronic toxicity study of methanol extract of P. minus at 250, 500, 1000 and 2000 mg/kg were conducted in both sexes of Sprague Dawley rats. There were no changes observed in the extract treated animal's body weight, food and water intake, motor coordination, behaviour and mental alertness. The values of haematological and biochemical parameters were not different between the treated and control animals. The relative organ weights of extract-treated animals did not differ with that of control animals. Based on the present findings, the methanol extract of P. minus leaves could be considered safe up to the dose of 2000 mg/kg.

Vasorelaxant properties of Vernonia amygdalina ethanol extract and its possible mechanism.

CONTEXT: Vernonia amygdalina Del. (VA) (Asteraceae) is commonly used to treat hypertension in Malaysia. OBJECTIVE: This study investigates the vasorelaxant mechanism of VA ethanol extract (VAE) and analyzes its tri-step FTIR spectroscopy fingerprint. MATERIALS AND METHODS: Dried VA leaves were extracted with ethanol through maceration and concentrated using rotary evaporator before freeze-dried. The vasorelaxant activity and the underlying mechanisms of VAE using the cumulative concentration (0.01-2.55 mg/mL at 20-min intervals) were evaluated on aortic rings isolated from Sprague Dawley rats in the presence of antagonists. RESULTS: The tri-step FTIR spectroscopy showed that VAE contains alkaloids, flavonoids, and saponins. VAE caused the relaxation of pre-contracted aortic rings in the presence and absence of endothelium with EC50 of 0.057 ± 0.006 and 0.430 ± 0.196 mg/mL, respectively. In the presence of Nω-nitro-l-arginine methyl ester (EC50 0.971 ± 0.459 mg/mL), methylene blue (EC50 1.203 ± 0.426 mg/mL), indomethacin (EC50 2.128 ± 1.218 mg/mL), atropine (EC50 0.470 ± 0.325 mg/mL), and propranolol (EC50 0.314 ± 0.032 mg/mL), relaxation stimulated by VAE was significantly reduced. VAE acted on potassium channels, with its vasorelaxation effects significantly reduced by tetraethylammonium, 4-aminopyridine, barium chloride, and glibenclamide (EC50 0.548 ± 0.184, 0.158 ± 0.012, 0.847 ± 0.342, and 0.304 ± 0.075 mg/mL, respectively). VAE was also found to be active in reducing Ca2+ released from the sarcoplasmic reticulum and blocking calcium channels. CONCLUSIONS: The vasorelaxation effect of VAE involves upregulation of NO/cGMP and PGI2 signalling pathways, and modulation of calcium/potassium channels, and muscarinic and ß2-adrenergic receptor levels.

Overview of Antagonists Used for Determining the Mechanisms of Action Employed by Potential Vasodilators with Their Suggested Signaling Pathways.

This paper is a review on the types of antagonists and the signaling mechanism pathways that have been used to determine the mechanisms of action employed for vasodilation by test compounds. Thus, we exhaustively reviewed and analyzed reports related to this topic published in PubMed between the years of 2010 till 2015. The aim of this paperis to suggest the most appropriate type of antagonists that correspond to receptors that would be involved during the mechanistic studies, as well as the latest signaling pathways trends that are being studied in order to determine the route(s) that atest compound employs for inducing vasodilation. The methods to perform the mechanism studies were included. Fundamentally, the affinity, specificity and selectivity of the antagonists to their receptors or enzymes were clearly elaborated as well as the solubility and reversibility. All the signaling pathways on the mechanisms of action involved in the vascular tone regulation have been well described in previous review articles. However, the most appropriate antagonists that should be utilized have never been suggested and elaborated before, hence the reason for this review.

PRELIMINARY INVESTIGATION OF NORMOGLYCEMIC, ANTI-HYPERGLYCEMIC AND DYSLIPIDEMIC ACTIVITIES OF DIFFERENT EXTRACTS OF TINOSPORA CRISPA ON DIABETIC RAT.

Tinospora crispa is an indigenous medicinal plant belonging to Menispermaceae family, known localy as "akar patawali" or as "akar seruntum". Different parts of this plant are used for various therapeutic purposes for treatment of hypertension, stimulation of appetite, protection from mosquito bites and to treat ailments like jaundice, wounds, intestinal worms and skin infections, tooth and stomach aches, coughs, asthma and pleurisy. The stems were washed, dried, pulverized using Wiley Laboratory Mill apparatus and stored in dry air-tight plastic containers until use. Then, they were extracted successively with petroleum ether, chloroform, methanol and finally with water by maceration. The solvent was evaporated from each extract (using rotary evaporator), dried extract were stored at -4°C until used. Animals were randomly divided into six groups and each group having 6 animals for two sets of experiments. In the first test, healthy rats were treated orally with the plant extracts (1 g/kg) suspended in Tween 80. In the second test, the diabetic rats were fasted overnight. The test groups of 6 diabetic rats were treated orally with extracts of Tinospora crispa (1 g/kg), glibenclamide (10 mg/kg) and 10% Tween 80, (10 mL/kg), respectively. In these results, there was no significant effect on blood glucose levels in normal rats treated with different extracts of Tinospora crispa. The water extract of Tinospora crispa decreased the glucose levels in diabetic rats and has the ability to reduce lipid profile in diabetic rats as compared to control diabetic rats.

Vernonia amygdalina simultaneously suppresses gluconeogenesis and potentiates glucose oxidation via the pentose phosphate pathway in streptozotocin-induced diabetic rats.

BACKGROUND: This study evaluated the impact of Vernonia amygdalina (VA) on the transcription of key enzymes involved in cellular modulation of glucose in streptozotocin-induced diabetic rats in a bid to understand the possible anti-diabetic mechanism of VA. METHODS: The chloroform fraction of VA (200 mg/kg and 400 mg/kg body weight) was administered to SDRs for 7 and 14 days. Thereafter, the expression (transcription) of key carbohydrate regulatory genes was evaluated in selected tissues - adipose, muscle and liver. Also, the body weight and blood glucose changes were monitored. RESULTS: A 14-day administration of 200 mg and 400 mg of the extract and metformin (500 mg/kg) showed a striking decrease (P <0.05) in the expression of the gluconeogenic enzymes - fructose 1,6-bisphosphatase, phosphoenol pyruvate carboxykinase and glucose 6-phosphatase in the liver and muscle compared to the diabetic control. These genes were highly expressed in tissues of untreated diabetic rats (P <0.05) indicating severe gluconeogenesis. Furthermore, the extract as well as metformin significantly increased glucose oxidation via the pentose phosphate pathway (PPP) i.e. increased expression of the glucose 6-phosphate dehydrogenase (G6PDH) gene (P <0.05) in the liver. Conversely, the expression of the G6PDH in the muscle and adipose tissues significantly decreased (P <0.05), suggesting enhanced utilization of NADPH and ribose in the clearance of reactive oxygen species and for expression of other relevant genes respectively. Also, transcription of the cell proliferation regulatory enzyme, phosphatidylinositol 3-kinase increased in the liver, but decreased in the muscle and adipose tissues (P <0.05) upon treatment with the extract or metformin, implying that the liver responded to the VA and metformin treatments more than other organs. The extract administration also caused a decrease in the expression of key enzymes of glycolysis namely hexokinase and phosphofructokinase, suggestive of a glucose sparing for ribose and NADPH production in PPP. CONCLUSION: Overall, data obtained in this study suggest that VA exerts little or no effect on glycolysis; rather, it may achieve its anti-diabetic action by a simultaneous suppression of gluconeogenesis and potentiation of glucose oxidation via PPP pathway, almost exclusively in the liver.

Standardized extract of Ficus deltoidea stimulates insulin secretion and blocks hepatic glucose production by regulating the expression of glucose-metabolic genes in streptozitocin-induced diabetic rats.

BACKGROUND: Recently, there has been increasing interest in Ficus deltoidea Jack. (Moraceae) due to its chemical composition and the potential health benefits. The present study was undertaken to investigate the effect of extracts of F. deltoidea leaves on diabetes. METHODS: The petroleum ether, chloroform and methanol extracts of F. deltoidea were prepared and subjected to standardization using preliminary phytochemical and HPLC analysis. Dose selection was made on the basis of acute oral toxicity study (50-5000 mg/kg b. w.) as per OECD guidelines. Diabetes mellitus was induced with streptozotocin and rats found diabetic were orally administered with the extract (250, 500 and 1000 mg/kg) for 14 days. Levels of blood glucose and insulin were measured in control as well as diabetic rats on 0, 7 and 14th day. In addition, glucose metabolism regulating gene expression was assessed using RT-PCR. RESULTS: HPLC analysis revealed that the methanol extract is enriched with C-glycosylflavones particularly, vitexin and isovitexin. In oral glucose tolerance test, oral administration of the methanol extract increased the glucose tolerance. The methanol extract showed significant (P < 0.01) antidiabetic activity. The extract treatment caused significant reduction (p < 0.01) in elevated fasting blood glucose level in streptozotocin-induced diabetic rats. The streptozotocin-related weight loss in rats was noticeably reversed by the extract treatment. Finally, RT-PCR analysis revealed a novel mechanisms for the anti-diabetic action of methanol extract of F. deltoidea. The extract exerted its effect via an increase of insulin secretion which impeded the hepatic glucose production, via down-regulation of phosphoenolpyruvate carboxykinase and glucose-6-phosphatase genes expression on one hand, and up-regulation of hepatic GK and PPARγ genes expression on the other hand. The extract caused an increased expression of GLUT-4 gene expression in skeletal muscles which leads to normalize the hyperglycemia. The extract also nullified the toxic effects of streptozitocin by blocking its entry into the islet ß-cells through reducing the expression of GLUT-2 gene. CONCLUSION: It can be concluded that, F. deltoidea could potentially inhibits the streptozitocin-induced hyperglycemia in rats. Further the herb can be utilized as useful remedy for alleviation of diabetes complications.

Effect of extraction solvents and plant parts used on the antihyperlipidemic and antioxidant effects of Garcinia atroviridis: a comparative study.

BACKGROUND: Garcinia atroviridis is a seasonal fruit plant found in many parts of South East Asia. The fruit rind is used in cooking and traditionally consumed for various reasons, including to lower blood cholesterol. A comparative study was undertaken to investigate the influence of extraction solvents and plant parts used on the lipid-lowering and antioxidant activities of Garcinia atroviridis. RESULTS: Aqueous extracts showed better antihyperlipidemic activity than the methanol extracts. Aqueous extract of ripe fruit showed the most potent antihyperlipidemic activity, comparable to that of atorvastatin. It significantly reduced the total cholesterol (P < 0.05), triglycerides (P < 0.01), low-density lipoprotein (P < 0.01), very-low-density lipoprotein (P < 0.01) and atherogenic index (P < 0.01). In contrast, antioxidant activities of methanol extracts of all parts of G. atroviridis were higher than their respective aqueous extracts, whereby the stem and leaves extracts showed better antioxidant activities than the fruits. CONCLUSION: Aqueous and methanol extracts of G. atroviridis showed higher antihyperlipidemic and antioxidant effects, respectively. Total phenolic and flavonoid contents showed significant correlations with antioxidant but not with antihyperlipidemic activities, indicating the involvement of other compounds. Contrary to the traditional belief, the present findings suggest that the fruit has higher antihyperlipidemic potential than the fruit rind.

Multi-constituent synergism is responsible for anti-inflammatory effect of Azadirachta indica leaf extract.

CONTEXT: Azadirachta indica A. Juss. (Meliaceaes) leaves have been used traditionally to treat swelling and rheumatism in Indian cultures. OBJECTIVE: To fractionate A. indica leaf extracts using bioactivity guided manner for identification of the active anti-inflammatory principles. MATERIALS AND METHODS: Polarity-gradient sequential extracts (petroleum ether, chloroform, methanol, and water) of A. indica leaves were screened for their anti-inflammatory potential using the carrageenan-induced rat paw edema model (1 g/kg). The chloroform extract was sequentially fractionated to obtain n-hexane (F-1), n-hexane-chloroform (F-2), and chloroform (F-3) fractions and their inhibitory effect on rat paw edema was evaluated (500 mg/kg). Inhibitory effect of F-2 on granuloma formation, plasma interleukin (IL-1), and tumor necrosis factor (TNF-α) was assessed at the doses of 100, 200, and 400 mg/kg using the cotton pellet assay in rats. Three sub-fractions (SF-1, SF-2, and SF-3) were obtained upon chromatography of F-2, and their inhibitory effect on cyclooxygenase was assessed at 200 µg/mL concentration. The sub-fractions were subjected to gas chromatography-mass spectrometry (GC-MS). RESULTS: All the extracts showed significant anti-inflammatory effect; however, chloroform extract was the most effective against paw edema (53.25% inhibition). The three fractions of chloroform extract showed significant effect, while F-2 being the most potent (51.02%). F-2 demonstrated dose-dependent inhibition of granuloma and cytokines. Interestingly, all the sub-fractions of F-2 inhibited COX-1 and COX-2 with almost equal potential. GC-MS revealed that chemically the sub-fractions were totally different from each other. DISCUSSION AND CONCLUSION: Anti-inflammatory effect of A. indica is a result of cumulative and synergistic effects of diversified constituents with varying polarities that collectively exert the effect via suppression of cyclo-oxygenases and cytokines (IL-1 and TNF-α).

Flavonoids eupatorin and sinensetin present in Orthosiphon stamineus leaves inhibit inflammatory gene expression and STAT1 activation.

Cytokines and other inflammatory mediators, such as prostaglandin E2 (PGE2) and nitric oxide (NO) produced by cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), respectively, activate and drive inflammation and therefore serve as targets for anti-inflammatory drug development. Orthosiphon stamineus is an indigenous medicinal plant of Southeast Asia that has been traditionally used in the treatment of rheumatoid arthritis, gout, and other inflammatory disorders. The present study investigated the anti-inflammatory properties of Orthosiphon stamineus leaf chloroform extract (CE), its flavonoid-containing CE fraction 2 (CF2), and the flavonoids eupatorin, eupatorin-5-methyl ether (TMF), and sinensetin, identified from the CF2. It was found that CE (20 and 50 µg/mL) and CF2 (20 and 50 µg/mL) inhibited iNOS expression and NO production, as well as PGE2 production. Eupatorin and sinensetin inhibited iNOS and COX-2 expression and the production of NO (IC50 5.2 µM and 9.2 µM for eupatorin and sinensetin, respectively) and PGE2 (IC50 5.0 µM and 2.7 µM for eupatorin and sinensetin, respectively) in a dose-dependent manner. The extracts and the compounds also inhibited tumor necrosis factor α (TNF-α) production (IC50 5.0 µM and 2.7 µM for eupatorin and sinensetin, respectively). Eupatorin and sinensetin inhibited lipopolysaccharide (LPS)-induced activation of transcription factor signal transducers and activators of transcription 1α (STAT1α). Furthermore, eupatorin (50 mg/kg i. p.) and sinensetin (50 mg/kg i. p.) inhibited carrageenan-induced paw inflammation in mice. The results suggest that CE and CF2, as well as the known constituents of CF2, i.e., eupatorin and sinensetin, have meaningful anti-inflammatory properties which may be utilized in the development of novel anti-inflammatory treatments.

Safety assessment of methanol extract of red dragon fruit (Hylocereus polyrhizus): acute and subchronic toxicity studies.

Recently, the fruits of Hylocereus polyrhizus, known as red dragon fruit, have received much attention from growers worldwide. However, there is little toxicological information regarding the safety of repeated exposure to these fruits. The present study evaluated the potential toxicity of a methanol extract of H. polyrhizus fruit after acute and subchronic administration in rats. In the acute toxicity study, single doses of fruit extract (1250, 2500 and 5000 mg/kg) were administered to rats by oral gavage, and the rats were then monitored for 14 days. In the subchronic toxicity study, the fruit extract was administered orally to rats at doses of 1250, 2500 and 5000 mg/kg/day for 28 days. There was no mortality or signs of acute or subchronic toxicity. There was no significant difference in body weight, relative organ weight or hematological parameters in the subchronic toxicity study. Biochemical analysis showed some significant changes, including creatinine, globulin, total protein and urea levels. No abnormality of internal organs was observed between treatment and control groups. The lethal oral dose of the fruit extract is more than 5000 mg/kg and the no-observed-adverse-effect level (NOAEL) of the extract for both male and female rats is considered to be 5000 mg/kg per day for 28 days.

Potent α-glucosidase and α-amylase inhibitory activities of standardized 50% ethanolic extracts and sinensetin from Orthosiphon stamineus Benth as anti-diabetic mechanism.

BACKGROUND: In the present study, we tested a 50% ethanolic extract of Orthosiphon stamineus plants and its isolated bioactive compound with respect to their α-glucosidase and α-amylase inhibitory activities. METHODS: Bioactive flavonoid sinensetin was isolated from 50% ethanolic extract of Orthosiphon stamineus. The structure of this pure compound was determined on the NMR data and the α-glucosidase and α-amylase inhibitory activities of isolated sinensetin and 50% ethanolic extract of Orthosiphon stamineus were evaluated. RESULTS: In vitro studies of a 50% ethanolic extract of O. stamineus and the isolated sinensetin compound showed inhibitory activity on α-glucosidase (IC50: 4.63 and 0.66 mg/ml, respectively) and α-amylase (IC50: 36.70 mg/ml and 1.13 mg/ml, respectively). Inhibition of these enzymes provides a strong biochemical basis for the management of type 2 diabetes via the control of glucose absorption. CONCLUSION: Alpha-glucosidase and α-amylase inhibition could the mechanisms through which the 50% ethanolic extract of O. stamineus and sinensetin exert their antidiabetic activity, indicating that it could have potential use in the management of non-insulin-dependent diabetes.

Mutagenic and antimutagenic assessment of methanol leaf extract of Myristica fragrans (Houtt.) using in vitro and in vivo genetic assays.

The role of diets in causing cancers necessitates the ongoing search for natural antimutagens of promising anticancer therapeutics. This study determined the potential anticancer efficacy of the leaf extract of Myristica fragrans (Houtt.). Methanol leaf extract of M. fragrans (Houtt.) alone was screened for mutagenicity in the bacterial reverse mutation (Ames) test, using the Salmonella typhimurium TA100 strain, the Allium cepa, and the mouse in vivo bone marrow micronucleus tests. The antimutagenicity of this extract against benzo[a]pyrene- and cyclophosphamide-induced mutations was evaluated. An antioxidant test on the extract was performed with 2,2-diphenyl-1-picrylhydrazyl, using butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as the standards, whereas its phytochemicals were elucidated by following the gas chromatography/mass spectrometry protocol. In S. typhimurium (TA100), the mutagenicity ratio at 200,500 and 1,000 µg/well was >2. Cell division in the A. cepa root tips and mouse bone marrow was significantly (P ≤ 0.05) inhibited at 2,000 and 4,000 mg/kg, whereas the observed chromosomal aberrations and micronucleated polychromatic erythrocytes were non-dose-related and were insignificantly (P ≥ 0.05) different from the negative control. Inhibition of benzo[a]pyrene- and cyclophosphamide-induced mutagenicity by this extract was above 40%. Half-maximal inhibitory concentration of the extract in the antioxidant test was lower than that of BHA and BHT. Phytochemical compounds, possessing antioxidant activity, may be responsible for the observed effects, suggesting a strong antimutagenic activity of the MeOH leaf extract of M. fragrans, a necessary characteristic of a promising anticancer agent.

Screening of stepping forces in an arthritic rat model using a novel analgesic meter and data acquisition system.

The stepping forces of normal and Freund Complete Adjuvant (FCA)-induced arthritic rats were studied in vivo using a proposed novel analgesic meter. An infrared charge-coupled device (CCD) camera and a data acquisition system were incorporated into the analgesic meter to determine and measure the weight of loads on the right hind paw before and after induction of arthritis by FCA injection into the paw cavity. FCA injection resulted in a significant reduction in the stepping force of the affected hind paw. The stepping force decreased to the minimum level on day 4 after the injection and then gradually increased up to day 25. Oral administration of prednisolone significantly increased the stepping forces of FCA-induced arthritic rats on days 14 and 21. These results suggest that the novel device is an effective tool for measuring the arthritic pain in in vivo studies even though walking is a dynamic condition.

Bioactivity-guided isolation of ethyl-p-methoxycinnamate, an anti-inflammatory constituent, from Kaempferia galanga L. extracts.

This study evaluated the anti-inflammatory effect of Kaempferia galanga (KG) using an activity-guided approach. KG rhizomes were serially extracted with petroleum ether, chloroform, methanol and water. These extracts (2 g/kg each) were tested for their ability to inhibit carrageenan-induced rat paw edema. The chloroform extract was found to exert the highest inhibition (42.9%) compared to control (p < 0.001), hence it was further fractionated by washing serially with hexane, hexane-chloroform (1:1) and chloroform. The chloroform fraction (1 g/kg) showed the highest inhibitory effect (51.9%, (p < 0.001), on carrageenan-induced edema. This chloroform fraction was further fractionated with hexane-chloroform (1:3) and chloroform, and of the two fractions, the hexane-chloroform sub-fraction was the most effective in inhibiting edema (53.7%, p < 0.001). GC-MS analysis of the active sub-fraction identified ethyl-p-methoxycinnamate (EPMC) as the major component, which was re-crystallized. EPMC dose-dependently inhibited carrageenan-induced edema with an MIC of 100 mg/kg. Moreover, in an in vitro study, EPMC non-selectively inhibited the activities of cyclooxygenases 1 and 2, with IC50 values of 1.12 µM and 0.83 µM respectively. These results validate the anti-inflammatory activity of KG which may be exerted by the inhibition of cyclooxygenases 1 and 2. EPMC isolated from this plant may be the active anti-inflammatory agent.

Evaluation of anti-cancer activity of Acanthester planci extracts obtained by different methods of extraction.

Acanthaster planci, the crown-of-thorns starfish, naturally endowed with the numerous toxic spines around the dorsal area of its body. Scientific investigations demonstrated several toxico-pharmacological efficacies of A. planci such as, myonecrotic activity, hemorrhagic activity, hemolytic activity, mouse lethality, phospholipase A2 (PLA2) activity, capillary permeability-increasing activity, edema-forming activity, anticoagulant activity and histamine-releasing activity from mast cells. The present study was performed to evaluate the cytotoxic activity of A. planci extracts obtained by different methods of extraction on MCF-7 and HCT-116, human breast and colon cancer cell lines, respectively. Results of the cell proliferation assay showed that PBS extract exhibited very potent cytotoxic activity against both MCF-7 and HCT-116 cell lines with IC(50) of 13.48 µg/mL and 28.78 µg/mL, respectively, while the extracts prepared by Bligh and Dyer method showed moderate cytotoxicity effect against MCF-7 and HCT-116 cell lines, for chloroform extract, IC(50) = 121.37 µg/mL (MCF-7) and 77.65 µg/mL (HCT-116), and for methanol extract, IC(50) = 46.11 µg/mL (MCF-7) and 59.29 µg/mL (HCT-116). However, the extracts prepared by sequential extraction procedure from dried starfish found to be ineffective. This study paves the way for further investigation on the peptide composition in the PBS extract of the starfish to discover potential chemotherapeutic agents.

Moringa oleifera Lam. leaf extracts reverse metabolic syndrome in Sprague Dawley rats fed high-fructose high fat diet for 60-days.

Background: Moringa oleifera Lam. has been used traditionally for the treatment of different cardio-metabolic disorders. So, the aim was to assess its leaf extracts in metabolic syndrome rat model.Methods: Out of the total 36-rats, 6 rats were given normal matched diet (NMD) while the rest were provided high-fat diet and 20% fructose (HFD-20%F). Moringa oleifera leaf extracts were administered orally for 30 days. Body weight, blood glucose, BMI, blood pressure, lipids, insulin, insulin resistance, MCP-1, visceral fat and liver weight were evaluated.Results: Sixty-days feeding with HFD-20%F produced the metabolic syndrome features like hyperinsulinemia, insulin resistance, and increase in low-density lipoprotein (LDL), visceral fat, and liver weight significantly (p<.05) than the rats receiving (NMD). Moringa oleifera treatment for 30 days significantly provided the mitigation against metabolic syndrome features.Conclusion: Moringa oleifera Lam. leaf extract might be a good alternative herbal choice in the treatment of metabolic syndrome disease.