Most cited article - PubMed ID 26731378
In vitro synergistic effect of Hibiscus sabdariffa aqueous extract in combination with standard antibiotics against Helicobacter pylori clinical isolates
Thymus bovei Benth. (TB) is an important plant in the traditional medicine of the Mediterranean region. This study investigates the health-promoting properties of TB essential oil (TB-EO) for its possible use in clinical practice with regards to its cytotoxic, anti-herpes simplex virus type 2 (HSV-2), and antihypertensive (through inhibition of human angiotensin-converting enzyme; ACE) properties. The phytochemical profile of EO (99.9%) was analyzed by Gas Chromatography with Flame-Ionization Detection (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS). In this study, all biological methods were performed at the level of in vitro studies. The results showed that TB-EO exerted remarked cytotoxic properties against human cervical carcinoma cells, colon cancer cells, and lung adenocarcinoma cells with the half-maximal inhibitory concentration (IC50) values of 7.22, 9.30, and 8.62 µg/mL, respectively, in comparison with that of standard anticancer drug cisplatin with IC50 values of 4.24, 5.21, and 5.43 µg/mL, respectively. Fascinatingly, TB-EO showed very weak cytotoxicity on the healthy human fetal lung fibroblast cells with an IC50 value of 118.34 µg/mL compared with that of cisplatin (IC50 = 10.08 µg/mL). TB-EO, its main component geraniol, TB-EO combined with acyclovir (ACV) along with standard ACV, have displayed pronounced inhibitory properties against the replication of HSV-2 with the half-maximal effective concentration (EC50) values of 2.13, 1.92, 0.81 and 1.94 µg/mL, respectively, with corresponding selectivity indices (SI) 98.59, 109.38, 259.26 and 108.25, respectively. TB-EO and geraniol at a concentration of 15 µg/mL showed prominent inhibitory activities against ACE with % of inhibition 95.4% and 92.2%, respectively, compared with that of standard inhibitor captopril (99.8%; 15 µg/mL). Molecular docking studies were performed to unveil the mechanism of action of geraniol as well as structural parameters necessary for anti-HSV-2 activity (through the inhibition of HSV-2 protease) and ACE inhibition. This is the first report on the chemical composition of Egyptian TB-EO along with the above-mentioned biological activities. Our results may be considered as novel findings in the course of a search for new and active anticancer, anti-HSV-2 and antihypertensive agents, and expand the medicinal value of this plant and its phytochemicals in clinical practice.
- Keywords
- HSV-2, Thymus bovei Benth., anticancer, antihypertensive, essential oil, phytochemical profile,
- Publication type
- Journal Article MeSH
Studies on enzyme inhibition remain a crucial area in drug discovery since these studies have led to the discoveries of new lead compounds useful in the treatment of several diseases. In this study, protocatechuic acid (PCA), an active compound from Hibiscus sabdariffa L. has been evaluated for its inhibitory properties against jack bean urease (JBU) as well as its possible toxic effect on human gastric epithelial cells (GES-1). Anti-urease activity was evaluated by an Electrospray Ionization-Mass Spectrometry (ESI-MS) based method, while cytotoxicity was assayed by the MTT method. PCA exerted notable anti-JBU activity compared with that of acetohydroxamic acid (AHA), with IC50 values of 1.7 and 3.2 µM, respectively. PCA did not show any significant cytotoxic effect on (GES-1) cells at concentrations ranging from 1.12 to 3.12 µM. Molecular docking study revealed high spontaneous binding ability of PCA to the active site of urease. Additionally, the anti-urease activity was found to be related to the presence of hydroxyl moieties of PCA. This study presents PCA as a natural urease inhibitor, which could be used safely in the treatment of diseases caused by urease-producing bacteria.
- Keywords
- ESI-Mass spectrometry, Hibiscus sabdariffa L., cytotoxicity, molecular docking, protocatechuic acid, urease inhibitors,
- MeSH
- Cell Line MeSH
- Hibiscus chemistry MeSH
- Spectrometry, Mass, Electrospray Ionization MeSH
- Hydroxybenzoates chemistry MeSH
- Hydroxamic Acids chemistry MeSH
- Humans MeSH
- Molecular Docking Simulation methods MeSH
- Urease antagonists & inhibitors MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- acetohydroxamic acid MeSH Browser
- Hydroxybenzoates MeSH
- Hydroxamic Acids MeSH
- protocatechuic acid MeSH Browser
- Urease MeSH
Stomach infection with Helicobacter pylori (H. pylori) causes severe gastroduodenal diseases in a large number of patients worldwide. The H. pylori infection breaks up in early childhood, persists lifelong if not treated, and is associated with chronic gastritis and an increased risk of peptic ulcers and gastric cancer. In recent years, the problem of drug-resistant strains has become a global concern that makes the treatment more complicated and the infection persistent at higher levels when the antibiotic treatment is stopped. Such problems have led to the development of new strategies to eradicate an H. pylori infection. Currently, one of the most important strategies for the treatment of H. pylori infection is the use of urease inhibitors. Despite the fact that large numbers of molecules have been shown to exert potent inhibitory activity against H. pylori urease, most of them were prevented from being used in vivo and in clinical trials due to their hydrolytic instability, toxicity, and appearance of undesirable side effects. Therefore, it is crucial to focus attention on the available opportunities for the development of urease inhibitors with suitable pharmacokinetics, high hydrolytic stability, and free toxicological profiles. In this commentary, we aim to afford an outline on the current status of the use of urease inhibitors in the treatment of an H. pylori infection, and to discuss the possibility of their development as effective drugs in clinical trials.
- Keywords
- Helicobacter pylori (H. pylori) infection, children, drug development, pharmacokinetics, urease inhibitors,
- Publication type
- Journal Article MeSH
For decades, treatment of infectious diseases has been a strong focus of interest, for both researchers and healthcare providers. Chronic infection with Helicobacter pylori (H. pylori) has been reported to be associated with several diseases, such as ulcer disease, gastric adenocarcinoma and mucosa-associated lymphoid tissue (MALT) lymphoma. Infection with H. pylori is generally acquired during childhood and can persist indefinitely, if not treated systematically. Unfortunately, although several strategies have shown high efficacy results, treatment of the H. pylori infection fails in about 25%-30% of infected children. One main reason for this is due to the extensive use of antibiotics, which has created antibiotic resistance, associated with other adverse effects as well. Therefore, it is crucial to find alternative strategies to combat this resistance, and increase treatment efficacy results. Probiotics, which are live microorganisms that are orally administrated, have been found to be a useful regimen in the treatment of the H. pylori infection in children. Their use as a dietary supplement alone, or in combination with antibiotics, resulted in reduced side effects and higher efficacy rates of the H. pylori infection in children. Some probiotics can be considered an adjunctive treatment, especially when eradication of the H. pylori infection fails during initial treatment, and to help reduce adverse effects. However, the evidence of the beneficial role of probiotics is limited due to the small number of clinical trials that have been conducted and heterogeneity across studies in strains and dosage. Additionally, no investigations have been carried out in asymptomatic children. Therefore, large well-conducted studies are needed to evaluate the efficacy and safety of probiotics as an adjuvant therapy of the H. pylori infection.
- Keywords
- Helicobacter pylori infection, children, dietary supplements, eradication treatment, probiotics,
- Publication type
- Editorial MeSH