Current Drug Discovery Technologies - Volume 16, Issue 2, 2019

Background: Portulaca oleracea L. (Purslane) has been used in traditional medicine against hepatic injury, although its actual efficacy has not been fully understood. The present study aimed to critically review the recent literature data from 1990 to 2017 regarding the hepato-protective effects of Portulaca oleracea L. and its underlying mechanisms. Methods: Online literature resources were checked using different search engines such as Medline, PubMed, Iran Medex, Scopus, and Google Scholar to identify articles, editorials, and reviews about antidotal effects of Portulaca oleracea L. against hepatotoxic agents. Results: Few studies have indicated that Portulaca oleracea L. shows protective effects against hepatotoxic agents. However, due to lack of information in humans, more studies are needed to confirm the efficacy of Portulaca oleracea L. as a hepato-protective agent. Conclusion: The study found that Portulaca oleracea L. may be effective on hepatotoxicity by modulating oxidative stress and inflammation.

Dihydropyrimidinones are extremely advantageous small sized molecules owning adaptable pharmaceutical properties. With a molecular formula C4H6N2O, they hold a wide range of biological activities. It is a heterocyclic moiety having two N-atoms at positions 1 and 3. They are derivatives of pyrimidine containing an additional ketone group. They have inspired development of a wide range of synthetic methods for preparation and chemical transformations. Taking into consideration their structural similarity and involvement with DNA and RNA, they have become very imperative in the world of synthetic organic chemistry. Aryl substituted moieties and their derivatives are significant class of substances in medicinal and organic chemistry. Many alkaloids from natural marine sources comprising dihydropyrimidinones core have been isolated which possess fascinating biological properties. Intensive explorations have been carried out on these compounds because they possess close similitude to clinically used nifedipine, nicardipine etc. which are also Biginelli product analogues. Due to the interesting pharmacological properties associated with the privileged DHPM structures, the Biginelli reaction and related procedures have received increasing attention in recent years.

PKC is a family of serine-threonine kinases which play crucial roles in the regulation of important signal transduction pathways in mammalian cell-biology. These enzymes are themselves regulated by various molecules that can serve as ligands to the regulatory domains and translocate PKC to membrane for activity. The role of PKC in the modulation of both proliferative and apoptotic signaling in cancer has become a subject of immense interest after it was discovered that PKC regulates a myriad of enzymes and transcription factors involved in carcinogenic signaling. Therefore, PKC has served as an attractive target for the development of newer generation of anti-cancer drugs. The following review discusses the potential of PKC to be regarded as a target for anti-cancer therapy. We also review all the molecules that have been discovered so far to be regulators/activators/inhibitors of PKC and also how far these molecules can be considered as potential candidates for anti-cancer drug development based on PKC.

Introduction and Background: Linum usitatissimum L., known as common Flax or linseed, from the family Linnaceae, has long been cultivated in different nations due to its applications in medicine and industry. The present study aims to collect nearly all available information about chemical constituents of Flax, as well as pharmacological properties and confirmed clinical usages of it. Methods: We searched through databases such as Scopus and PubMed for relevant literature using the keywords: Linum usitatissimum, pharmacology and phytochemical from the beginning to 13 Aug 2017. Nearly 60 relevant papers, relating to a pharmacological and phytochemical constituent of L. usitatissimum were selected. Results and Discussion: According to our researches, various properties were attributed to L. usitatisimum including antioxidant, immunomodulatory, anti-inflammatory, antimicrobial, antiprotozoal, insecticidal, analgesic, anti-hyperlipidemia, anti-hyperglycemic, anti-tumor, wound healing and Feticidal activities. There were also many reports on disease prevention and healing properties of the flax. Diseases like: GI disorders, cardiovascular, urogenital, respiratory diseases and some neurological syndromes were mentioned to be treated by Flax. The application of Flax in drug formulations was also investigated. Conclusion: Despite so much animal studies that have been accomplished, there have not been enough clinical trials done on pharmacological properties of L. usitatissimum. Therefore, this study could be considered as a concise and up to date overview for further facile studies and clinical trials over the valuable plant, L. usitatissimum.

Background: Prediction of proteins’ secondary structure is one of the major steps in the generation of homology models. These models provide structural information which is used to design suitable ligands for potential medicinal targets. However, selecting a proper tool between multiple Secondary Structure Prediction (SSP) options is challenging. The current study is an insight into currently favored methods and tools, within various contexts. Objective: A systematic review was performed for a comprehensive access to recent (2013-2016) studies which used or recommended protein SSP tools. Methods: Three databases, Web of Science, PubMed and Scopus were systematically searched and 99 out of the 209 studies were finally found eligible to extract data. Results: Four categories of applications for 59 retrieved SSP tools were: (I) prediction of structural features of a given sequence, (II) evaluation of a method, (III) providing input for a new SSP method and (IV) integrating an SSP tool as a component for a program. PSIPRED was found to be the most popular tool in all four categories. JPred and tools utilizing PHD (Profile network from HeiDelberg) method occupied second and third places of popularity in categories I and II. JPred was only found in the two first categories, while PHD was present in three fields. Conclusion: This study provides a comprehensive insight into the recent usage of SSP tools which could be helpful for selecting a proper tool.

Background: Leishmaniasis reaches millions of people around the world. The control of the disease is difficult due to the restricted access to the diagnosis and medication, and low adherence to the treatment. Thus, more efficient drugs are needed and natural products are good alternatives. Iridoids, natural products with reported leishmanicidal activity, can be exploited for the development of anti- Leishmania drugs. The aim of this study was to isolate and to investigate the in vitro activity of iridoids against Leishmania amazonensis and to compare the activity in silico of these compounds with those reported as active against this parasite. Methods: Iridoids were isolated by chromatographic methods. The in vitro activity of asperuloside (1) and geniposide (2) from Escalonia bifida, galiridoside (3) from Angelonia integerrima and theveridoside (4) and ipolamiide (5) from Amphilophium crucigerum was investigated against promastigote forms of Leishmania amazonensis. Molecular modeling studies of 1-5 and iridoids cited as active against Leishmania spp. were performed. Results: Compounds 1-5 (5-100 μM) did not inhibit the parasite survival. Physicochemical parameters predicted for 1-5 did not show differences compared to those described in literature. The SAR and the pharmacophoric model confirmed the importance of maintaining the cyclopentane[C]pyran ring of the iridoid, of oxygen-linked substituents at the C1 and C6 positions and of bulky substituents attached to the iridoid ring to present leishmanicidal activity. Conclusion: The results obtained in this study indicate that iridoids are a promising group of secondary metabolites and should be further investigated in the search for new anti-Leishmania drugs.

Background: Breast cancer is one of the common causes of mortality for women in Iran and other parts of the world. The substantial increasing rate of breast cancer in both developed and developing countries warns the scientists to provide more preventive steps and therapeutic measures. This study is conducted to investigate the impact of neurotransmitters (e.g., Dopamine) through their receptors and the importance of cancers via damaging immune system. It also evaluates dopamine receptors gene expression in the women with breast cancer at stages II or III and dopamine receptor D2 (DRD2) related agonist and antagonist drug effects on human breast cancer cells, including MCF-7 and SKBR-3. Methods: The patients were categorized into two groups: 30 native patients who were diagnosed with breast cancer at stages II and III, with the mean age of 44.6 years and they were reported to have the experience of a chronic stress or unpleasant life event. The second group included 30 individuals with the mean age of 39 years as the control group. In order to determine the RNA concentration in all samples, the RNA samples were extracted and cDNA was synthesized. The MCF-7 cells and SKBR-3 cells were treated with dopamine receptors agonists and antagonists. The MTT test was conducted to identify oxidative and reductive enzymes and to specify appropriate dosage at four concentrations of dopamine and Cabergoline on MCF-7 and SKBR-3 cells. Immunofluorescence staining was done by the use of a mixed dye containing acridine orange and ethidiume bromide on account of differentiating between apoptotic and necrotic cells. Flow cytometry assay was an applied method to differentiate necrotic from apoptotic cells. Results: Sixty seven and thirty three percent of the patients were related to stages II and III, respectively. About sixty three percent of the patients expressed ER, while fifty seven percent expressed PR. Thirty seven percent of the patients were identified as HER-2 positive. All types of D2-receptors were expressed in PBMC of patients with breast cancer and healthy individuals. The expression of the whole dopamine receptor subtypes (DRD2-DRD4) was carried out on MCF-7 cell line. The results of RT-PCR confirmed the expression of DRD2 on SKBR-3 cells, whereas the other types of D2- receptors did not have an expression. The remarkable differences in gene expression rates between patients and healthy individuals were revealed in the result of the Real-time PCR analysis. The over expression in DRD2 and DRD4 genes of PBMCs was observed in the patients with breast cancer at stages II and III. The great amount of apoptosis and necrosis occurred after the treatment of MCF-7 cells by Cabergoline from 25 to 100 μmolL-1 concentrations. Conclusion: This study revealed the features of dopamine receptors associated with apoptosis induction in breast cancer cells. Moreover, the use of D2-agonist based on dopamine receptors expression in various breast tumoral cells could be promising as a new insight of complementary therapy in breast cancer.

Objective: In Iranian Traditional Medicine, the herbs with cold and wet temperament can help to improve insomnia. Portulaca oleracea has a cold and wet temperament, so the present study was carried out to investigate the sleep-prolonging effect of Portulaca oleracea. Methods: This work was an experimental study on mice which were randomly divided into these groups: saline (control); Diazepam: positive control); hydro-alcoholic extract of Portulaca oleracea (12.5, 25, 50, 75 and 100 mg/kg) by Soxhlet apparatus and maceration; in the effective (dose25 mg/kg), different fractions of extract were tested. Ethyl acetate fraction (EAF:); N hexane fraction (n-HF); water fraction (WF). All the test compounds were injected intraperitoneally (IP) 30 minutes before pentobarbital administration (30 mg/kg). Duration and latency of pentobarbital-induced sleep were recorded. Also, LD50 of Portulaca oleracea extract was determined and the possible neurotoxicity of the extract was tested on neural PC12 cells. Besides, 30 min after administration of hydroalcoholic extract (HAE) motor coordination (rota-rod test) was assessed. Results: HAE increased the duration of pentobarbital-induced sleep at doses of 25, 50, 75 and 100 mg/kg. The hypnotic effect of HAE was comparable to that induced by diazepam. Similarly, WF, EAF, and NHF at 25 mg/kg could increase sleep duration. The sleep latency was decreased by HAE and NHF but not by WF and EAF. The LD50 value for HAE was found to be 4.8 g/Kg. HAE and its fractions did not show neurotoxic effect in cultured PC12-cell line, also HAE did not affect the animals performance on the rotarod test. Conclusion: The present data demonstrated that Portulaca oleracea potentiates sleeping behaviors. The main components responsible for the hypnotic effects of this plant is most likely a non-polar agents which is found in NHF. Isolation of the active constituents may yield a novel sedative drug.

Background: The incidence of invasive fungal infections caused by Candida spp. has increased continuously in recent decades, especially in populations of immunocompromised patients or individuals hospitalized with serious underlying diseases. Therefore, the goal of our study was the search for new potent Candida albicans inhibitors via the development of QSAR models that could speed up this search process. A number of the most promising 1,3-oxazol-4-yltriphenylphosphonium derivatives with predicted activities were synthesized and experimentally tested. Furthermore, the toxicity of the studied compounds was determined in vitro using acetylcholinesterase enzyme as a biological marker. Methods: The classification QSAR models were created using Random Forests (WEKA-RF), k-Nearest Neighbors and Associative Neural Networks methods and different combinations of descriptors on the Online Chemical Modeling Environment (OCHEM) platform. Antifungal properties of the investigated compounds were performed using standard disk diffusion method. The enzyme inhibitory action of the compounds was determined by modified Ellman's method using acetylcholinesterase from the electric organ of Electrophorus electricus. Results: Three classification QSAR models were developed by the WEKA-RF, k-NN and ASNN methods using the ALogPS, E-State indices and Dragon v.7 descriptors. The predictive ability of the models was tested through cross-validation, giving a balanced accuracy BA = 80-91%. All compounds demonstrated good antifungal properties against Candida spp. and slight inhibition of the acetylcholinesterase activity. Conclusion: The high percentage of coincidence between the QSAR predictions and the experimental results confirmed the high predictive power of the developed QSAR models that can be applied as tools for finding new potential inhibitors against Candida spp. Furthermore, 1,3-oxazol-4- yl(triphenyl)phosphonium salts could be considered as promising candidates for the treatment of candidiasis and the disinfection of medical equipment.

Background: Farsetia hamiltonii Royle, also known as Hiran Chabba grows in desert regions. It is widely used as folk medicine to treat joint pains, diarrhea and diabetes. However, its antioxidant and iron chelation abilities both in vitro and in vivo have not yet been investigated. Methods: The 70% methanolic extract of F. hamiltonii (FHME) was investigated for its free radical scavenging and iron chelation potential, in vitro. An iron-overload situation was established by intraperitoneal injection of iron-dextran in Swiss albino mice, followed by oral administration of FHME. Liver damage and serum parameters due to iron-overload were measured biochemically and histopathologically to test iron-overload remediation and hepatoprotective potential of FHME. Phytochemical analyses were performed to determine its probable bioactive components. Results: FHME showed promising antioxidant activity, scavenged various reactive oxygen and nitrogen species and chelated iron in vitro. FHME reduced liver iron, serum ferritin, normalized serum parameters, reduced oxidative stress in liver, serum and improved liver antioxidant status in ironoverloaded mice. It also alleviated liver damage and fibrosis as evident from biochemical parameters and morphological analysis of liver sections. The phytochemical analyses of FHME reflected the presence of alkaloids, phenols, flavonoids and tannins. HPLC analysis indicated presence of tannic acid, quercetin, methyl gallate, catechin, reserpine, ascorbic acid and gallic acid. Conclusion: Based on the experimental outcome, FHME, an ethnologically important plant can be envisaged as excellent antioxidant and iron chelator drug capable of remediating iron-overload induced hepatotoxicity and the bioactive compounds present in FHME might be responsible for its efficacy.

Background: Diabetic foot ulcer (DFU) is one of the most common complications of diabetic patients. Mostly, non-healing DFU leads to infection, gangrene, amputation and even death. High costs and poor healing of the wounds need a new treatment such as alternative medicine. So, the aim of this study was to evaluate the efficacy of Aloe vera/ Plantago major gel (Plantavera gel) in healing of DFU. Methods: Forty patients with DFU enrolled in a double-blind randomized clinical trial. The patients who were randomly assigned into the intervention group (n = 20), received topical Plantavera gel in addition to the routine cares, whereas the patients in the control group (n = 20), received topical Placebo gel in addition to the routine cares. Intervention was done twice a day for 4 weeks in the both groups. Photography and an evaluation of DFU healing were conducted by a checklist and then were scored at baseline and at the end of each week. The collected data was analyzed by SPSS software. Results: At the end of the study, there was a significant difference between the two groups in terms of total ulcer score (P<0.001) and Plantavera gel significantly reduced the ulcer surface comparing with the control group (P=0.039). However, there was not a significant difference between the two groups (P=0.263) in terms of the ulcer depth. During this study, no side effect was observed for Plantavera gel in the intervention group. Conclusion: Topical Plantavera gel seems to be an effective, cheap and safe treatment. Of course, further studies are required to confirm the properties of the wound healing of this gel.

Background: According to new studies, only 60% of depressed patients respond to pharmaceutical treatment while suffering from their side effects. Natural products as adjuvant or alternative therapies should be examined to find safer and more effective ways to cope with depression. Objective: To find out the potential benefits of a combined herbal drug based on Echium amoenum compared with citalopram in the treatment of Major Depressive Disorder.. Design and Setting: In psychiatry clinics of Mashhad University of Medical Sciences, 50 patients who met the criteria for Major Depressive Disorder based on DSM-5 were studied in a parallel randomized controlled trial. Intervention: Subjects were randomly assigned to receive Echium amoenum compound syrup (EACS) or citalopram tablet for 8 weeks. Outcome Measures: The efficacy of treatments and recurrence of disease were surveyed and compared according to Hamilton depression rating scale at weeks 0, 4, 8, 12. Results: Patients in both groups of citalopram and EACS showed remarkable reduction in scores of Hamilton questionnaire. At the eighth week of treatment, the mean scores in EACS group were significantly lower than citalopram group (p-value = 0.03). 52% of patients suffered from various complications in citalopram group while just 12% of patients in EACS group reported few complications. Conclusion: Clinical efficacy of this herbal drug was significantly higher than citalopram, and complications were also less and lower in EACS group. Further studies with larger groups and para-clinical assessments such as serologic tests and QEEG would improve our understanding of the impacts and mechanisms of EACS.