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Two new E/Z neo-clerodane diterpene isomers, trivially named stachaegyptin D (1) and E (2), together with known compounds, stachysolon monoacetate (3) and stachysolon diacetate (4), were isolated from an organic-solvent extract of the medicinal herb Stachys aegyptiaca. Structures were elucidated by a combination of spectroscopic methods, including HREIMS, 1H, 13C, DEPT, and 2D NMR analysis, as well as, first time X-ray analysis for stachysolone (3). All isolated metabolites showed some activity against the human hepatocellular cell line, HepG2. Compound 4 was the most active with an IC50 of 59.5 μM.

Artificially designed miRNAs mimics and inhibitors that specifically target known oncogenes have attracted significant research attention. Herein, we aimed to explore whether MIR-375, MIR-145, and MIR-224 are involved in induction of apoptosis of CRC cells by regulating apoptosis-mediating genes MTDH, MAP3K1, PDK1, BAX, and BCL-XL. MTT assay was used to assess cell growth. Apoptosis was determined in terms of caspase activity measurement and phosphatidylserine detection using annexin V staining by flow cytometry. Quantitative real time PCR, Western blotting, and luciferase reporter assay were carried out to validate genes regulation and targeting by miRNAs. We found that ectopic expression of MIR-375 and MIR-145, and inhibition of MIR-224 can decrease cell growth and induce cell ability to undergo early apoptosis. At mRNA level, transfected cells displayed down-regulation of MTDH, PDK1 and BCL-XL, while BAX and MAP3K1 were up-regulated. Protein expression of MTDH was decreased in cells transfected with MIR-145 mimic and MIR-224 inhibitor but remained unchanged in MIR-375 mimic-transfected cells. Furthermore, MAP3K1 protein expression exibited a decreased level after MIR-375 transient expression with no significant change after MIR-145 mimic or MIR-224 inhibitor transfection. Luciferase reporter assay revealed that MIR-375 and MIR-145 can bind to 3'UTR of MTDH, supporting that MTDH is directly targeted by both miRNAs. Similarly, MAP3K1 was found to be directly regulated by MIR-375. The study concluded that the expression modulation of tumor suppressors MIR-375 and MIR-145, and oncomiR MIR-224 have the ability to induce apoptosis of CRC cells through regulation of apoptosis mediating genes MTDH, MAP3K1, PDK1, BCL-XL and BAX.

Phytochemical investigation of Stachys aegyptiaca resulted in the characterization of three new diterpenes (1-3) together with eleven known compounds including four neo-clerodane diterpenes and seven flavonoid aglycones. Structure elucidation was performed by spectroscopic analysis by HRFABMS, 1D and 2D NMR and X-ray. Isolated compounds were screened for anti-inflammatory activity using a lipopolysaccharide-induced nitric oxide inhibition assay employing murine macrophage cells. Among the assayed compounds, 13 (calycopterin) showed a concentration-dependent inhibition of LPS-induced nitric oxide release with a IC50 of 62.5 μM.

The alcoholic extract of Adhatoda vasica showed strong and reversible inhibition of the enzyme acetyl cholinesterase (AChE) with an IC50 = 294 μg/mL. Phytochemical study of the total alcoholic extract of A. vasica yielded four known compounds vasicine, vasicinone, vasicole and anisotine. Vasicine reversibly and competitively inhibited AChE with ki value 11.24 μM. On the other hand, rest of isolated alkaloids showed no/or weak inhibitory effect on AChE. Vasicine showed binding similarity to both galantamine and tacrine in the catalytic site. The obtained results support the multi-pharmacological properties of vasicine, which can be considered as a promising inhibitor for acetyl cholinesterase where it can be used directly or indirectly for the development of efficient anti-Alzheimer drug.

Elevation of acetylcholinesterase enzyme (AChE) has been reported to be implicated in the etiology of Alzheimer disease (AD). One of the encouraged strategies to fight AD is the plant-derived inhibitors. Amaryllidaceae species are enriched source of alkaloids. The inhibitory properties of roots and bulbs of Pancratium maritimum L. against AChE have been previously reported. In the present study, the flowers of the wild Egyptian P. maritimum were subjected to screening assays to evaluate its potency as inhibitor to AChE. Besides, its antioxidant and cytotoxic properties were also addressed. The acetylcholinesterase inhibitory properties of P. maritimum ; total extract and its alkaloid mixture were examined using Ellman’s assay. The direct antioxidant examination was carried out using DPPH assay whereas the indirect was monitored by the ability to protect Hepa1c1c7 cells against the induced cytotoxicity produced by tert-butyl hydroperoxide (TBHP). The cytotoxic effect of the total extract and crude alkaloid mixture was evaluated against the human liver hepatoma cell line (HepG2). P. maritimum flowers showed significant inhibitory activity against AChE. The potency of the alkaloid mixture, representing 5.0% of the flowers weight (IC 50 ; 22.02 ± 0.59 μg/ml) was about fourfold of its total extract (IC 50 ; 97.67 ± 4.06 μg/ml). The total extract was able to protect about 33.4% of Hepa1c1c7 against the induced intoxication that carried by TBHP rather than the alkaloid mixture. Weak antioxidant and cytotoxic activities were recorded by both examined samples. Flowers of the Egyptian P. maritimum L. could be an enriched source of AChE inhibitors.

Background The multidrug resistance (MDR) phenotype encounters a major challenge to the success of established chemotherapy in cancer patients. We hypothesized that cytotoxic medicinal plants with novel phytochemicals can overcome MDR and kill MDR-cells with similar efficacy as drug sensitive cells. Purpose We evaluated plant extracts from an unexplored ecosystem in Egypt with unusual climate and nutrient conditions for their activity against sensitive and multidrug-resistant cancer cell lines. Material and methods/study design Methylene chloride: methanol (1:1) and methanol: H2O (7:3) extracts of 40 plants were prepared resulting in a sum of 76 fraction containing compounds with varying polarity. The resazurin reduction assay was employed to evaluate the cytotoxicity of these extracts on five matched pairs of drug-sensitive and their drug-resistant cell lines. Flow cytometry and Western blotting was used to determine cell cycle analyses, apoptosis, and autophagy. Reactive oxygen species (ROS) were measured spectrophotometrically. Results Extracts derived from Withania obtusifolia (WO), Jasonia candicans (JC), Centaurea lippii (CL), and Pulicaria undulata (PU) were the most active ones among 76 extracts from 40 Egyptian medicinal plants. They showed a significant reduction of cell viability on drug-sensitive CCRF-CEM leukemia cell line with IC50 values less than 7 µg/ml. Low cross-resistance degrees were observed in multidrug-resistant CEM/ADR5000 cells towards CL (1.82-fold) and JC (6.09-fold). All other drug-resistant cell lines did not reveal cross-resistance to the four extracts. Further mechanistic assessment have been studied for these four extracts. Conclusion The methylene chloride: methanol (1:1) fractions of WO, JC, CL, and PU are promising cytotoxic extracts that could be used to combat MDR cancer cells through different cell death pathways.