scholarly journals Compounds with Anti-Onchocercal Activity from Voacanga africana Stapf (Apocynaceae): Identification and Molecular Modeling

Author(s):  
Smith Babiaka ◽  
Conrad Simoben ◽  
Kennedy Abuga ◽  
James Mbah ◽  
Rajshekhar Karpoormath ◽  
...  

A new iboga-vobasine-type isomeric bisindole alkaloid named voacamine A (1), along with eight known compounds, voacangine (2), voacristine (3), coronaridine (4), tabernanthine (5), iboxygaine (6), voacamine (7), voacorine (8), and conoduramine (9), were isolated from the stem bark of Voacanga africana. The structures of the compounds were determined by comprehensive spectroscopic analyses (1D- and 2D-NMR). Compounds 1, 2, 3, 4, 6, 7 and 8 were found to inhibit the motility of both the microfilariae (Mf) and adult male worms of Onchocerca ochengi, in a dose-dependent manner, but were only moderately active on the adult female worms upon biochemical assessment at 30 μM drug concentrations. The IC50 values of the isolates are 2.49-5.49 µM for microfilariae and 3.45-17.87 µM for adult males. Homology modeling was used to generate a 3D model of the the O. ochengi thioredoxin reductase target and docking simulation attempted to offer an explanation of the anti-onchocercal structure-activity relationship (SAR) of the isolated compounds. These alkaloids are new potential leads for the development of antifilirial drugs. The results of this study validate the traditional use of V. africana in the treatment of human onchocerciasis.

Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 70 ◽  
Author(s):  
Smith B. Babiaka ◽  
Conrad V. Simoben ◽  
Kennedy O. Abuga ◽  
James A. Mbah ◽  
Rajshekhar Karpoormath ◽  
...  

A new iboga-vobasine-type isomeric bisindole alkaloid named voacamine A (1), along with eight known compounds—voacangine (2), voacristine (3), coronaridine (4), tabernanthine (5), iboxygaine (6), voacamine (7), voacorine (8) and conoduramine (9)—were isolated from the stem bark of Voacangaafricana. The structures of the compounds were determined by comprehensive spectroscopic analyses. Compounds 1, 2, 3, 4, 6, 7 and 8 were found to inhibit the motility of both the microfilariae (Mf) and adult male worms of Onchocerca ochengi, in a dose-dependent manner, but were only moderately active on the adult female worms upon biochemical assessment at 30 μM drug concentrations. The IC50 values of the isolates are 2.49–5.49 µM for microfilariae and 3.45–17.87 µM for adult males. Homology modeling was used to generate a 3D model of the O. ochengi thioredoxin reductase target and docking simulation, followed by molecular dynamics and binding free energy calculations attempted to offer an explanation of the anti-onchocercal structure–activity relationship (SAR) of the isolated compounds. These alkaloids are new potential leads for the development of antifilarial drugs. The results of this study validate the traditional use of V. africana in the treatment of human onchocerciasis.


Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6626
Author(s):  
Edwin R. Sukandar ◽  
Sutin Kaennakam ◽  
Pia Raab ◽  
Xuehong Nöst ◽  
Kitiya Rassamee ◽  
...  

Garcinia picrorhiza, a woody plant native to Sulawesi and Maluku Islands, Indonesia, has been traditionally used as a wound healing ointment. In our continuous search for bioactive compounds from this plant, 15 phenolic compounds were isolated from its stem bark, including a previously undescribed dihydroisocoumarin, 2′-hydroxyannulatomarin, and two undescribed furanoxanthones, gerontoxanthone C hydrate and 3′-hydroxycalothorexanthone. The structures of the new metabolites were elucidated on the basis of spectroscopic analysis, including 1D and 2D NMR and HRESIMS. Gerontoxanthone C hydrate possessed cytotoxicity against four cancer cells (KB, HeLa S3, MCF-7, and Hep G2) with IC50 values ranging from 5.6 to 7.5 µM. Investigation on the anti-inflammatory activities showed that 3′-hydroxycalothorexanthone inhibited NO production in RAW 264.7 and BV-2 cell lines with IC50 values of 16.4 and 13.8 µM, respectively, whereas only (−)-annulatomarin possessed inhibition activity on COX-2 enzyme over 10% at 20 µM. This work describes the presence of 3,4-dihydroisocoumarin structures with a phenyl ring substituent at C-3, which are reported the first time in genus Garcinia. These findings also suggest the potential of furanxanthone derivatives as cytotoxic and anti-inflammatory agents for further pharmacological studies.


2019 ◽  
pp. 249-257
Author(s):  
AA Aderinola ◽  
J Ejiofor ◽  
OE Oyinloye ◽  
TA Fasanya ◽  
E Eremu

Background: Diarrhoeal disease is the second leading cause of morbidity and mortality in developing countries requiring urgent attention. Many of the conventional anti-diarrhoeal drugs cause serious adverse effects, hence the need to screen various plants for their medicinal values becomes imperative. Objective: To investigate the anti-diarrhoeal activity of ethanolic stem bark extract of Newbouldia laevis in castor-oil induced diarrhoea in rats. Methods: The stem bark of Newbouldia laevis collected from Abeokuta, Ogun State, was air-dried, ground, macerated in 90% ethanol and concentrated to dryness in a water bath and then reconstituted using distilled water. Fifty (50) albino rats of both sexes used for the study were divided into two groups: A and B with twenty-five (25) rats per group. Group A was used for the gastro-intestinal motility test using charcoal meal while Group B was used for castor-oil induced diarrhoea test and the number of stool pellets was counted over an hour period. Results: The extract (250-1000mg/kg) showed significant (p = 0.0399) anti-diarrhoeal activity by decreasing the distance of the gastrointestinal movement of charcoal meal in the treated rats and also inhibited the severity of diarrhoea induced by castor-oil in a dose-dependent manner when compared with the control (distilled water). This activity could be attributed to phytochemicals like flavonoids and tannins present in Newbouldia laevis. Conclusion: The results showed that stem bark extract of Newbouldia laevis possesses a significant anti-diarrhoeal property and this supports the traditional use of the plant in the treatment of diarrhoea.


Pharmacology ◽  
2018 ◽  
Vol 102 (1-2) ◽  
pp. 81-87 ◽  
Author(s):  
Hongshan Ge ◽  
Lanlan Chen ◽  
Ying Su ◽  
Chunyan Jin ◽  
Ren-Shan Ge

Background: Estradiol, produced by aromatase (CYP19A1), is very important for reproduction. Folpet, captan, and captafol belong to the phthalimide class of fungicides. They are used to protect the leaves of plants or fruits. They could be endocrine disruptors and may disrupt CYP19A1 activity. Methods: In the present study, we investigated the effects of folpet, captan, and captafol on estradiol production and human CYP19A1 activity in JEG-3 cells. Results: Folpet, captan, and captafol decreased estradiol production in JEG-3 cells in a concentration-dependent manner. Folpet, captan, and captafol inhibited human CYP19A1 with inhibitory concentration (IC50) values of 3.55, 10.68, and 1.14 μmol/L respectively. These chemicals competitively inhibited human CYP19A1. Molecular docking simulation analysis showed that they tended to bind to the steroid-binding pocket of the CYP19A1. However, the required concentrations may not be relevant to the negligible systemic exposures in humans to these chemicals. Conclusion: Folpet, captan, and captafol are potential inhibitors of human CYP19A1.


1997 ◽  
Vol 78 (04) ◽  
pp. 1202-1208 ◽  
Author(s):  
Marianne Kjalke ◽  
Julie A Oliver ◽  
Dougald M Monroe ◽  
Maureane Hoffman ◽  
Mirella Ezban ◽  
...  

SummaryActive site-inactivated factor VIIa has potential as an antithrombotic agent. The effects of D-Phe-L-Phe-L-Arg-chloromethyl ketone-treated factor VIla (FFR-FVIIa) were evaluated in a cell-based system mimicking in vivo initiation of coagulation. FFR-FVIIa inhibited platelet activation (as measured by expression of P-selectin) and subsequent large-scale thrombin generation in a dose-dependent manner with IC50 values of 1.4 ± 0.8 nM (n = 8) and 0.9 ± 0.7 nM (n = 7), respectively. Kd for factor VIIa binding to monocytes ki for FFR-FVIIa competing with factor VIIa were similar (11.4 ± 0.8 pM and 10.6 ± 1.1 pM, respectively), showing that FFR-FVIIa binds to tissue factor in the tenase complex with the same affinity as factor VIIa. Using platelets from volunteers before and after ingestion of aspirin (1.3 g), there were no significant differences in the IC50 values of FFR-FVIIa [after aspirin ingestion, the IC50 values were 1.7 ± 0.9 nM (n = 8) for P-selectin expression, p = 0.37, and 1.4 ± 1.3 nM (n = 7) for thrombin generation, p = 0.38]. This shows that aspirin treatment of platelets does not influence the inhibition of tissue factor-initiated coagulation by FFR-FVIIa, probably because thrombin activation of platelets is not entirely dependent upon expression of thromboxane A2.


2018 ◽  
Vol 16 (S1) ◽  
pp. S119-S129
Author(s):  
I. Namoune ◽  
B. Khettal ◽  
A.M. Assaf ◽  
S. Elhayek ◽  
L. Arrar

Marrubium vulgare (Lamiaceae) is frequently used in traditional medicine to treat many illnesses from ancient times. Its beneficial effects include antibacterial, antioedematogenic, and analgesic activities. This study was designed to evaluate the antioxidant and anti-inflammatory activities of organic and aqueous extracts of the leaves, the flowers, the stems, and the roots of Marrubium vulgare. The total phenolic and flavonoid contents as well as the antioxidant and the anti-inflammatory effects of methanol, chloroform, ethyl acetate, and aqueous extracts have been investigated by using different in-vitro methods. It was found that the ethyl acetate extract from Marrubium vulgare stems had the highest total phenolic content, while the ethyl acetate extract from the leaves yielded a high concentration of flavonoids. The ethyl acetate extract from the stems exhibited the highest activity in scavenging of 2,2-diphenyl- 1-picrylhydrazyl (DPPH), as well as in protecting erythrocytes. The leaves aqueous extract exhibited the highest ferrous chelating activity and its methanolic extract was found to be the strongest inhibitor of lipid peroxidation in β-carotene bleaching assay. The leaves chloroform extracts as well as the flowers methanol, chloroform, and ethyl acetate extracts were found to decrease the pro-inflammatory tumor necrosis factor alpha (TNF-α) cytokine levels in a dose-dependent manner. On the other hand, the flowers methanolic extract and the leaves methanol, ethyl acetate, and aqueous extracts decreased the interleukin-1 beta (IL- 1β) release. It was also found that the methanol extract from the flowers and the chloroform extract from the stems of Marrubium vulgare inhibited interleukin-8 (IL-8) release. This study provides a scientific basis for the traditional use of Marrubium vulgare as an anti-inflammatory agent and for the plant to be considered as an important resource of natural antioxidants.


2019 ◽  
Vol 26 (7) ◽  
pp. 494-501 ◽  
Author(s):  
Sameer Suresh Bhagyawant ◽  
Dakshita Tanaji Narvekar ◽  
Neha Gupta ◽  
Amita Bhadkaria ◽  
Ajay Kumar Gautam ◽  
...  

Background: Diabetes and hypertension are the major health concern and alleged to be of epidemic proportions. This has made it a numero uno subject at various levels of investigation. Glucosidase inhibitor provides the reasonable option in treatment of Diabetes Mellitus (DM) as it specifically targets post prandial hyperglycemia. The Angiotensin Converting Enzyme (ACE) plays an important role in hypertension. Therefore, inhibition of ACE in treatment of elevated blood pressure attracts special interest of the scientific community. Chickpea is a food legume and seeds contain carbohydrate binding protein- a lectin. Some of the biological properties of this lectin hitherto been elucidated. Methods: Purified by ion exchange chromatography, chickpea lectin was tested for its in vitro antioxidant, ACE-I inhibitory and anti-diabetic characteristic. Results: Lectin shows a characteristic improvement over the synthetic drugs like acarbose (oral anti-diabetic drug) and captopril (standard antihypertensive drug) when, their IC50 values are compared. Lectin significantly inhibited α-glucosidase and α-amylase in a concentration dependent manner with IC50 values of 85.41 ± 1.21 ҝg/ml and 65.05 ± 1.2 µg/ml compared to acarbose having IC50 70.20 ± 0.47 value of µg/ml and 50.52 ± 1.01 µg/ml respectively. β-Carotene bleaching assay showed antioxidant activity of lectin (72.3%) to be as active as Butylated Hydroxylanisole (BHA). In addition, lectin demonstrated inhibition against ACE-I with IC50 value of 57.43 ± 1.20 µg/ml compared to captopril. Conclusion: Lectin demonstrated its antioxidant character, ACE-I inhibition and significantly inhibitory for α-glucosidase and α-amylase seems to qualify as an anti-hyperglycemic therapeutic molecule. The biological effects of chickpea lectin display potential for reducing the parameters of medically debilitating conditions. These characteristics however needs to be established under in vivo systems too viz. animals through to humans.


2019 ◽  
Vol 16 (6) ◽  
pp. 474-477 ◽  
Author(s):  
Pham Van Khang ◽  
Nguyen Thi Hien Lan ◽  
Le Quang Truong ◽  
Mai Thi Minh Chau ◽  
Mai Xuan Truong ◽  
...  

In this report, two new steroidal glycosides were isolated and determined from n-butanol fraction of A.asphodeloides. The structures were confirmed in comparison with the spectral data of known compounds by using different spectroscopic analysis approaches including 1D & 2D-NMR techniques and HRMS. The anti-proliferation screening against cancer cell lines A549 and HeLa indicated that compound 1 exhibited good inhibitory activities with IC50 values of 0.79 and 0.55 µg/mL, respectively.


2018 ◽  
Vol 15 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Xiaofeng Bao ◽  
Ying Xue ◽  
Chao Xia ◽  
Yin Lu ◽  
Ningjing Yang ◽  
...  

Background: Chlamydiae, characterized by a unique biphasic life cycle, are a group of Gram-negative obligate intracellular bacterial pathogens responsible for diseases in a range of hosts including humans. Benzylidene acylhydrazide CF0001 could inhibit chlamydiae independent of iron starvation and T3SS inhibition. This finding promoted us to design and synthesize more benzylidene acylhydrazides to find novel anti-chlamydial agents. Methods: The carboxylic acids 1a-1d were coupled with Boc-hydrazide inpresence of EDCI and DMAP to obtain the intermediate 2a-2d in 60-62% yields. N-Boc deprotections were performed to obtain hydrazide hydrochloride salt 3a-3d. Nextly, the hydrazides were subjected to condensation with aldehydes to obtain benzylidene acylhydrazides 4a-4g in 30-52% yields in two steps. Results: Compound 4d exhibited best inhibitory effect on the formation and growth of chlamydial inclusions. The IC50 value of compound 4d for infectious progenies was 3.55 µM, better than 7.30 µM of CF0001. Conclusion: To find novel anti-chlamydial agents, we have designed and synthesized benzylidene acylhydrazides 4a-4g. Compounds 4a, 4d, 4g showed inhibitory activity on C. muridarum with the IC50 values from 3.55-12 µM. The 3,5-dibromo-4-hydroxyl substitutes on ring B are critical to keep their anti-chlamydial activity. Compound 4d inhibited C. muridarum in a dose-dependent manner without apparent cytotoxicity.


2019 ◽  
Vol 19 (11) ◽  
pp. 1399-1404 ◽  
Author(s):  
Yangcheng Liu ◽  
Wei Liu ◽  
Changlan Chen ◽  
Zheng Xiang ◽  
Hongwei Liu

Background and Purpose:: Patrinia villosa Juss is an important Chinese herbal medicine widely used for thousands of years, but few reports on the ingredients of the herb have been presented. In this study, we aim to isolate the bioactive compound from the plant. Material and Methods:: The air-dried leaves of P. villosa (15kg) were extracted three times with 70% EtOH under reflux. The condensed extract was suspended in H2O and partitioned with light petroleum, dichloromethane and n-BuOH. The dichloromethane portion was then subjected to normal-phase silica gel column chromatography, ODS silica gel column chromatography and semi-preparative HPLC to yield compound 1. Cytotoxicities of 1 were assayed on HepG2, A549 and A2780 cell lines. The mechanism of apoptosis and cell cycle on A549 was confirmed subsequently. Results: A new impecylone (Impecylone A) was isolated from the leaves of Patrinia villosa Juss, and its structures were established using 1D, 2D-NMR spectra and HR-ESI-MS. Impecylone A could selectivity inhibit HepG2 and A549 cell lines. The compound could induce apoptosis of A549 and arrest the cell cycle at G2/M phase in a dose-dependent manner. Conclusion: Impecylone A is a novel compound from Patrinia villosa Juss and could be a potential antitumor agent especially in the cell lines of A549.


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