Isolation of a novel isoprenylated phenolic compound and neuroprotective evaluation of Dodonaea viscosa extract against cerebral ischaemia-reperfusion injury in rats.

Dodonaea viscosa grows widely in Saudi Arabia, but studies evaluating its neuroprotective activity are lacking. Thus, this study aimed to isolate and identify the secondary metabolites and evaluate the neuroprotective effects of D. viscosa leaves. The isolation and identification of phytochemicals were performed using chromatographic and spectroscopic techniques. The neuroprotective potential of the extract was evaluated against focal cerebral ischaemia-reperfusion injury in rat model. Neurobehavioural deficits in the rats were evaluated, and their brains were harvested to measure infarct volume and oxidative biomarkers. Results revealed the presence of three compounds: a novel isoprenylated phenolic derivative that was elucidated as 4-hydroxy-3-(3'-methyl-2'-butenyl) phenyl 1-O-ß-D-apiosyl-(1''' â†’ 6'')- ß-D-glucopyranoside (named Viscomarfadol) and two known compounds (isorhamnetin-3-O-rutinoside and epicatechin (4-8) catechin). Pre-treatment of the rats with the extract improved neurological outcomes. It significantly reduced neurological deficits and infarct volume; significantly reduced lipid peroxidation, as evidenced by decreased malondialdehyde levels; and significantly elevated antioxidant (superoxide dismutase, catalase, and glutathione) activities. These results indicate that D. viscosa is a promising source of bioactive compounds that can improve neurological status, decrease infarct volume, and enhance antioxidant activities in rats with cerebral ischaemic injury. Thus, D. viscosa could be developed into an adjuvant therapy for ischaemic stroke and other oxidative stress-related neurodegenerative disorders. Further investigations are warranted to explore other bioactive compounds in D. viscosa and evaluate their potential neuroprotective activities.

PI3K-AKT Pathway Modulation by Thymoquinone Limits Tumor Growth and Glycolytic Metabolism in Colorectal Cancer.

Colorectal cancer (CRC) is the third leading cause of death in men and the fourth in women worldwide and is characterized by deranged cellular energetics. Thymoquinone, an active component from Nigella sativa, has been extensively studied against cancer, however, its role in affecting deregulated cancer metabolism is largely unknown. Further, the phosphoinositide 3-kinase (PI3K) pathway is one of the most activated pathways in cancer and its activation is central to most deregulated metabolic pathways for supporting the anabolic needs of growing cancer cells. Herein, we provide evidence that thymoquinone inhibits glycolytic metabolism (Warburg effect) in colorectal cancer cell lines. Further, we show that such an abrogation of deranged cell metabolism was due, at least in part, to the inhibition of the rate-limiting glycolytic enzyme, Hexokinase 2 (HK2), via modulating the PI3/AKT axis. While overexpression of HK2 showed that it is essential for fueling glycolytic metabolism as well as sustaining tumorigenicity, its pharmacologic and/or genetic inhibition led to a reduction in the observed effects. The results decipher HK2 mediated inhibitory effects of thymoquinone in modulating its glycolytic metabolism and antitumor effects. In conclusion, we provide evidence of metabolic perturbation by thymoquinone in CRC cells, highlighting its potential to be used/repurposed as an antimetabolite drug, though the latter needs further validation utilizing other suitable cell and/or preclinical animal models.

Attitudes and Associated Demographic Factors Contributing towards the Abuse of Illicit Drugs: A Cross-Sectional Study from Health Care Students in Saudi Arabia.

Background and objective: The purpose of this study is to compare the attitudes, views, and factors that influence drug abuse among pharmacy and nursing students at a Saudi Arabian university. Materials and Methods: A cross-sectional study, was conducted among pharmacy and nursing students who are currently enrolled in the respective courses at the study site. The data were collected over 4 months from August to November 2019 using structured self-administered paper-based questionnaires. Results: Among the participants, pharmacy students accounted for 184 (58.2%) while 132 (41.8%) of the students were from nursing. More than a third of the students 129, (40.8%) smoked cigarettes. The majority of pharmacy (80.4%) and nursing students (67.4%) reported having undertaken a drug misuse course in college. Among the participants, 132 (41.7%) stated that an offer from friends, followed by joy seeking 129 (40.8%), parents' divorce 126 (39.8%), having access to drugs 125 (39.5%), family issues 110 (34.8%), 66 (20.8%) having a family member who is addicted, and 101 (31.9%) reported curiosity to be the factors regarding the use of abusive drugs. Transient euphoria (75.9%) followed by depression 197 (62.3%) was the most prevalent physical or psychological change that occurred following drug use. The family size and father's education have significantly affected the attitudes scores of the students (F = 5.188; p = 0.0001). Conclusion: In this study, joy-seeking, access to drugs, and family issues were found to be the major factors listed as reasons for drug abuse, with some of them being controllable or reversible. Educating about the adverse outcomes of abused drugs is warranted.

Box-Behnken Design (BBD)-Based Optimization of Microwave-Assisted Extraction of Parthenolide from the Stems of Tarconanthus camphoratus and Cytotoxic Analysis.

Parthenolide, a strong cytotoxic compound found in different parts of Tarchonanthus camphoratus which motivated the authors to develop an optimized microwave-assisted extraction (MEA) method using Box-Behnken design (BBD) for efficient extraction of parthenolide from the stem of T. camphoratus and its validation by high-performance thin-layer chromatography (HPTLC) and cytotoxic analysis. The optimized parameters for microwave extraction were determined as: 51.5 °C extraction temperature, 50.8 min extraction time, and 211 W microwave power. A quadratic polynomial model was found the most suitable model with R2 of 0.9989 and coefficient of variation (CV) of 0.2898%. The high values of adjusted R2 (0.9974), predicted R2 (0.9945), and signal-to-noise ratio (74.23) indicated a good correlation and adequate signal, respectively. HPTLC analyzed the parthenolide (Rf = 0.16) content in T. camphoratus methanol extract (TCME) at λmax = 575 nm and found it as 0.9273% ± 0.0487% w/w, which was a higher than expected yield (0.9157% w/w). The TCME exhibited good cytotoxicity against HepG2 and MCF-7 cell lines (IC50 = 30.87 and 35.41 µg/mL, respectively), which further supported our findings of high parthenolide content in TCME. This optimized MAE method can be further applied to efficiently extract parthenolide from marketed herbal supplements containing different Tarconanthus species.

Cytotoxicity and molecular docking analysis of racemolactone I, a new sesquiterpene lactone isolated from Inula racemosa.

CONTEXT: Traditionally, Inula racemosa Hook. f. (Asteraceae) has been reported to be effective in cancer treatment which motivated the authors to explore the plant for novel anticancer compounds. OBJECTIVE: To isolate and characterize new cytotoxic phytoconstituents from I. racemosa roots. MATERIALS AND METHODS: The column chromatography of I. racemosa ethyl acetate extract furnished a novel sesquiterpene lactone whose structure was established by NMR (1D/2D), ES-MS and its cytotoxic properties were assessed on HeLa, MDAMB-231, and A549 cell lines using MTT and LDH (lactate dehydrogenase) assays. Further, morphological changes were analyzed by flow cytometry, mitochondrial membrane potential, AO-EtBr dual staining, and comet assay. Molecular docking and simulation were performed using Glide and Desmond softwares, respectively, to validate the mechanism of action. RESULTS: The isolated compound was identified as racemolactone I (compound 1). Amongst the cell lines tested, considerable changes were observed in HeLa cells. Compound 1 (IC50 = 0.9 µg/mL) significantly decreased cell viability (82%) concomitantly with high LDH release (76%) at 15 µg/mL. Diverse morphological alterations along with significant increase (9.23%) in apoptotic cells and decrease in viable cells were observed. AO-EtBr dual staining also confirmed the presence of 20% apoptotic cells. A gradual decrease in mitochondrial membrane potential was observed. HeLa cells showed significantly increased comet tail length (48.4 µm), indicating broken DNA strands. In silico studies exhibited that compound 1 binds to the active site of Polo-like kinase-1 and forms a stable complex. CONCLUSIONS: Racemolactone I was identified as potential anticancer agent, which can further be confirmed by in vivo investigations.

Cell proliferation activity delineated by molecular docking of four new compounds isolated from the aerial parts of Suaeda monoica Forssk. ex. J.F. Gmel.

Using different chromatographic methods, four new compounds were isolated from the aerial parts of Suaeda monoica (Chenopodiaceae) along with 2-hydroxy-1-naphthoic acid (SCM-3). The structures of the new compounds were established as 6'-hydroxy-10'-geranilanyl naphtha-1-oate (SMC-1), 4,4,8ß,10ß-Tetramethyl-9ß-isobutanyl decalin-13-ol-13-O-ß-D-xylopyranoside (SCM-2), 6'-(2-hydroxynaphthalen-3-yl) hexanoic acid (SCM-4) and 1'-(2-Methoxy-3-naphthyl)-4'-(2''-methylbenzoyl)-n-butane (SMC-5) by IR, EIMS and NMR (1 & 2D) analyses. All compounds (50 µg/mL) were tested for cell proliferative potential on cultured human liver cell HepG2 cells by MTT assay. The results revealed a marked cell proliferative potential of all compounds (1.42-1.48 fold) as compared to untreated control. The results of molecular docking and binding with specific proteins such as PTEN (Phosphatase and Tensin homolog) and p53 also justify the cell proliferative potential of the isolated compounds. Glide program with Schrodinger suit 2018 was used to evaluate the binding between SMC compounds and proteins (PTEN and p53). The binding affinity of all compounds was in order of 104-105 M-1 towards both PTEN and p53. All the SMC compounds have been found to bind at the active site of PTEN, thereby may prevent the binding of phosphatidylinositiol 3,4,5-triphosphate (PI3P). In the locked position, PTEN would not be able to hydrolyze PI3P and hence the PI3P regulated signaling pathway remains active. Similarly, SMC molecules were found to interact with the amino acid residues (Ser99, Thr170, Gly199, and Asp224) which are critically involved in the formation of tetrameric p53. The blockage of p53 to attain its active conformation thus may prevent the recruitment of p53 on DNA and hence may promote cell proliferation.

Thermodynamic solubility and solvation behavior of ferulic acid in different (PEG-400 + water) binary solvent mixtures.

This work was carried out to determine solubility, solution thermodynamics, solvation behavior, and molecular interactions of a natural compound ferulic acid (FLA) in different '[polyethylene glycol-400 (PEG-400) + water]' binary solvent mixtures at 'T = 298.2 K to 318.2 K' and 'p = 0.1 MPa.' The mole fraction solubilities (xe) of FLA were determined by liquid chromatographic technique using a static equilibrium technique. The obtained solubility data of FLA were regressed using 'Van't Hoff, Apelblat, Yalkowsky-Roseman and Jouyban-Acree models.' The solubility of FLA (expressed in mole fraction) was enhanced with elevation in absolute temperature in each 'PEG-400 + water' binary solvent mixture evaluated. The maximum xe values of FLA were recorded in neat PEG-400 (1.94 × 10-1) at 'T = 318.2 K.' While, the minimum one was obtained in neat water (4.90 × 10-5) at 'T = 298.2 K.' The molecular interactions between FLA-PEG-400 and FLA-water were obtained by determination of activity coefficients of FLA in different 'PEG-400 + water' binary solvent mixtures. The physical data of activity coefficients recorded in this work suggested strong molecular interactions in FLA-PEG-400 in comparison with FLA-water. 'Apparent thermodynamic analysis' suggested an 'endothermic and entropy-driven dissolution' of FLA in each 'PEG-400 + water' binary solvent mixture investigated.

Comparative extraction and simple isolation improvement techniques of active constituents' momilactone A and B from rice husks of Oryza sativa by HPLC analysis and column chromatography.

This paper reports comparative extraction efficiencies and enhancement methods for natural herbicidal (growth inhibitors) compounds, momilactone A and B, respectively from the dried husks of Oryza sativa using different extraction techniques and different solvent systems. Four different extraction techniques viz. percolation, agitation with heat, sonication and soxhlet using five solvent systems as ethyl acetate, acetone, acetonitrile, methanol and methanol:water (8:2) were evaluated. In these studies, it was observed that maximum extract yield was obtained using in methanol and methanol/water mixture as extracting solvent by soxhlet technique although the content of total momilactones A and B was higher in the methanol/water mixture in comparison to other extractions. The successive and simple isolation enrichment technique for momilactones A and B were achieved by solid-matrix partitioning after the treatment of methanolic extract with charcoal and using ethyl acetate as extracting solvent for momilactones A and B. The quantitative analysis of the extraction and enrichment development protocol was validated by a simple, accurate, reproducible RP-HPLC-UV-VIS method using a binary gradient elution comprising of acetonitrile and water (70:30). The separation was achieved on a waters Spherisorb S10 ODS 2 column (250 × 4.6 mm, I.D., 10 µm) that achieved a greater degree of linearity within an overall concentration of extracts and momilactones A and B, 1 mg mL-1 and higher degree of correlation (0.9928 ≤ r2 ≤ 0.9936) for momilactones A and B. So far, comparative extraction of momilactones A and B and HPLC of these compounds has not been reported. Standards of momilactones A (1) and B (2) were isolated along with other two compounds as orizaterpenoid (3) and 7-ketostigmaterol (4) from ethyl acetate extract of rice hulls of O. sativa and checked purity by HPLC-PDA-MS and identification of these isolated compounds (1-4) by complete spectroscopic techniques as IR, 1H NMR, 13C NMR, 2D NMR and HR-MS. The qualitative analysis of momilactone A and B separation technique by thin layer chromatography was also developed.

The influence of variations of furanosesquiterpenoids content of commercial samples of myrrh on their biological properties.

Myrrh is an oleo-gum-resin produced in the stem of Commiphora myrrha (Burseraceae) and used for centuries for different medicinal purposes. The present work was designed to evaluate the cytotoxic and antioxidant properties of seventeen myrrh samples (S1-S17) obtained from different retail markets of Saudi Arabia and Yemen regions, along with two furanosesquiterpenoids (CM-1 and CM-2). The cytotoxicity assay was carried out on HepG2, MCF-7 and HUVEC cell lines. S2, S5, S10, S12, CM-1, CM-2 exhibited significant cytotoxicity against HepG2/MCF-7 cell lines [IC50 (µg/mL): 13.8/10, 14/10, 14.5/11.3, 18/13.2, 9.5/12.5, 10/15.8, respectively) compare to vinblastin (IC50 (µg/mL): 2/2.5) whereas the remaining samples were found as mild active or inactive. The antioxidant properties of the samples were tested by ß-carotene-bleaching and DPPH free radical scavenging methods where the samples S8 (1000 µg/mL) exhibited the highest ß-carotene bleaching (76.2%) and free radical scavenging activity (79.8%). The HPTLC analysis was performed on NP-HPTLC plate using toluene, chloroform and glacial acetic acid as mobile phase in ratio of 7:2.9:0.1 (V/V/V). The validated HPTLC method furnished sharp, intense and compact peaks of CM-1 and CM-2 at Rf = 0.39 and 0.44, respectively. The highest/lowest content of CM-1 and CM-2 were found in S12/S5 and S5/S17, respectively. The molecular docking studies of CM-1 and CM-2 with human DNA topoisomerase IIα have shown that both the compounds were bound the active sites of the respective enzymes. Molecular dynamics simulation studies further confirmed that the interactions of CM-1 and CM-2 with topoisomerase were stable in nature. This study will help us in selection of appropriate myrrh sample for the greater benefits of the population in the Middle East region.

Antidiabetic, antioxidant, molecular docking and HPTLC analysis of miquelianin isolated from Euphorbia schimperi C. Presl.

The present study demonstrates the miquelianin or quercetin 3-O-glucuronide (compound 1) isolated from aerial parts of Euphorbia schimperi exhibited significant results for antioxidant and antidiabetic potential. The compound 1 along with kaempferol 3-O-glucuronide (compound 2) and quercetin 3-O-rhamnoside (compound 3) isolated from the same source were quantified by validated HPTLC method. Antioxidant activity was determined by chemical means in terms of ABTS radical cation and DPPH radical scavenging activity. Compound 1 showed significant scavenging activity in both ABTS and DPPH assays as compared to standard BHA. In ABTS method IC50 values of compound 1 and standard BHA is found to be 58.90 ±â€¯3.40 µg/mL and 28.70 ±â€¯5.20 µg/mL respectively while in DPPH assay IC50 values of Compound 1 and standard BHA is 47.20 ±â€¯4.90 µg/mL and 34.50 ±â€¯6.20 µg/mL respectively. Antidiabetic effect was studied through α-amylase and α-glucosidase inhibitory activity. The mechanistic approach through molecular modelling also support the strong binding sites of compound 1 which showed significant α-amylase and α-glucosidase inhibitory activities with IC50 values 128.34 ±â€¯12.30 and 89.20 ±â€¯9.20 µg/mL respectively as compared to acarbose 64.20 ±â€¯5.60 and 52.40 ±â€¯4.60 µg/mL respectively. The results of validated RP-HPTLC analyses revealed the concentration of compound 1 found to be 16.39 µg/mg and for compound 2 and compound 3 as 3.92 and 14.98 µg/mg of dried extract, respectively.