Antidepressant effects of crocin and its effects on transcript and protein levels of CREB, BDNF, and VGF in rat hippocampus

BACKGROUND: Antidepressants have been shown to affect levels of brain-derived neurotrophic factor (BDNF) and VGF (non-acronymic) whose transcriptions are dependent on cAMP response element binding protein (CREB) in long term treatment. The aim of this study was to verify the subacute antidepressant effects of crocin, an active constituent of saffron (Crocus sativus L.), and its effects on CREB, BDNF, and VGF proteins, transcript levels and amount of active, phosphorylated CREB (P-CREB) protein in rat hippocampus. METHODS: Crocin (12.5, 25, and 50 mg/kg), imipramine (10 mg/kg; positive control) and saline (1 mL/kg; neutral control) were administered intraperitoneally (IP) to male Wistar rats for 21 days. The antidepressant effects were studied using the forced swimming test (FST) on day 21 after injection. Protein expression and transcript levels of genes in the rat hippocampus were evaluated using western blot and quantitative reverse transcription-polymerase chain reaction (qRT-PCR), respectively. RESULTS: Crocin significantly reduced the immobility time in the FST. Western blot analysis showed that 25 and 50 mg/kg of crocin increased the levels of CREB and BDNF significantly and dose dependently. All doses of crocin increased the VGF levels in a dose-dependent manner. Levels of p-CREB increased significantly by 50 mg/kg dose of crocin. Only 12.5 mg/kg crocin could significantly increase the transcript levels of BDNF. No changes in CREB and VGF transcript levels were observed in all groups. CONCLUSIONS: These results suggest that crocin has antidepressant-like action by increasing CREB, BDNF and VGF levels in hippocampus

Nanolipoparticles-mediated MDR1 siRNA delivery reduces doxorubicin resistance in breast cancer cells and silences MDR1 expression in xenograft model of human breast cancer

Objective(s): P-glycoprotein (P-gp) is an efflux protein, the overexpression of which has been associated with multidrug resistance in various cancers. Although siRNA delivery to reverse P-gp expression may be promising for sensitizing of tumor cells to cytotoxic drugs, the therapeutic use of siRNA requires effective carriers that can deliver siRNA intracellularly with minimal toxicity on target cells. We investigated a special class of PEGylated lipid-based nanoparticles (NP), named nanolipoparticles (NLPs), for siRNA- mediated P-gp downregulation. Materials and Methods: NLPs were prepared based on low detergent dialysis method. After characterization, we evaluated the effect of NLPs on siRNA delivery, and P-gp downregulation compared to oligofectamineTM (OFA) in vitro and in vivo. Results: Our results showed a significant decrease in P-gp expression and subsequent enhancement of chemosensitivity to doxorubicin in vitro. Although the effectiveness of NLPs for in vitro siRNA delivery compared to OFA was limited, the results of in vivo studies showed noticeable effectiveness of NLPs for systemic siRNA delivery. siRNA delivery using NLPs could downregulate MDR1 in tumor cells more than 80%, while OFA had a reverse effect on MDR1 expression in vivo. Conclusion: The results indicated that the prepared NLPs could be suitable siRNA delivery systems for tumor therapy

A colorimetric aptasensor for selective detection of oxytetracycline in milk, using gold nanoparticles and oxytetracline-short aptamer

Objective (s): In light of misuse of antibiotics in animal husbandry and their side effects on human health, there is an argent need to develop simple and rapid methods for determining the quantification of antibiotics in biological systems. Materials and Methods: In this work a facile and ultrasensitive colorimetric aptasensor was reported for detection of oxytetracycline (OTC) in water and milk samples employing OTC-short aptamer and gold nanoparticles (AuNPs). Results: In the presence of OTC, the interaction between OTC and its aptamer leads to the separation of OTC aptamer from the surface of AuNPs which is followed by the aggregation of AuNPs by salt, showing an evident color change from red to blue. On the contrary, in the absence of OTC, the attachment of aptamer on the surface of AuNPs can protect AuNPs against salt-induced aggregation with a wine-red color. The proposed aptasensor exhibits excellent sensitivity for detection of OTC with linear range between 20 to 2000 nM with limit of detection (LOD) as low as 10 nM. Furthermore, this strategy was applied to detect OTC in spiked milk samples and presented satisfying linear range from 25 to 1500 nM with the LOD of 20 nM. Conclusion: Owing to demonstrating appropriate sensitivity and selectivity, the designed biosensor can be considered as a promising tool to be applied in the field of biomedicine and food safety

The effects of crocin on spatial memory impairment induced by hyoscine: Role of NMDA, AMPA, ERK, and CaMKII proteins in rat hippocampus

Objective(s): Crocus sativus L. and its active constituent, crocin, have neuroprotective effects. The effects of crocin on memory impairment have been mentioned in studies but the signaling pathways  have not been evaluated. Therefore, the aim of this study was to evaluate the effects of crocin on the hyoscine-induced memory impairment in rat. Additionally, the level of NMDA (N-methyl-D-aspartate receptors), AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole-propionicd acid), ERK (extracellular signal-regulated kinases), CaMKII (calcium (Ca2+)/calmodulin (CaM)-dependent kinaseII) mRNA and proteins were determined in rat hippocampus. Materials and Methods: Crocin (10, 20, and 40 mg/kg), hyoscine (1.5 mg/kg), normal saline and rivastigmine  were administered intraperitoneally to male Wistar rats for 5 days. The effects on memory improvement were studied using Morris water maze (MWM) test. Then, the protein levels of NMDA, AMPA, ERK, pERK, CaMKII and p.CaMKII  in hippocampus were analized using the Western blot test. Furthermore, the mRNA levels of NMDA, AMPA, ERK and pCaMKII genes were evaluated using real-time quantitative reverse transcription-polymerase chain reaction (qRT- PCR) method. Results: Aadminestration of crocin (20 mg/kg) and rivastigmine  significantly improved learning and memory impairment induced by hyoscine. Also, administration of hyoscine reduced  protein level of pERK,  while treatment with crocin (20 mg/kg) recovered the protein level.  No changes were observed in the protein levels and mRNA gene expression of NMDA, AMPA, ERK, CaMKII and pCaMKII following adminestration of hyoscine or crocin. Conclusion: Adminestration of crocin improved memory and learning. The effect of crocin in this model can be mediated by alteration in pERK protein level in rat hippocampus

Design, synthesis and biological evaluation of novel coumarin-based benzamides as potent histone deacetylase inhibitors and anticancer agents

Histone deacetylases (HDACs) are attractive therapeutic targets for the treatment of cancer and other diseases. It has four classes (I-IV), among them especially class I isozyme are involved in promoting tumor cells proliferation, angiogenesis, differentiation, invasion and metastasis and also viable targets for cancer therapeutics. A novel series of coumarin-based benzamides was designed and synthesized as HDAC inhibitors. The cytotoxic activity of the synthesized compounds (8a-u) was evaluated against six human cancer cell lines including HCT116, A2780, MCF7, PC3, HL60 and A549 and a single normal cell line (Huvec). We evaluated their inhibitory activities against pan HDAC and HDAC1 isoform. Four compounds (8f, 8q, 8r and 8u) showed significant cytotoxicity with IC50 in the range of 0.53–57.59 μM on cancer cells and potent pan-HDAC inhibitory activity (consists of HDAC isoenzymes) (IC50 = 0.80–14.81 μM) and HDAC1 inhibitory activity (IC50 = 0.47–0.87 μM and also, had no effect on Huvec (human normal cell line) viability (IC50 > 100 μM). Among them, 8u displayed a higher potency for HDAC1 inhibition with IC50 value of 0.47 ± 0.02 μM near equal to the reference drug Entinostat (IC50 = 0.41 ± 0.06 μM). Molecular docking studies and Molecular dynamics simulation of compound 8a displayed possible mode of interaction between this compound and HDAC1enzym

Protective effect of thymoquinone, the active constituent of Nigella sativa fixed oil, against ethanol toxicity in rats

Objective(s): Long term consumption of ethanol may induce damage to many organs. Ethanol induces its noxious effects through reactive oxygen species production, and lipid peroxidation and apoptosis induction in different tissues and cell types. Previous experiments have indicated the antioxidant characteristics of thymoquinone, the active constituent of Nigella sativa fixed oil, against biologically dangerous reactive oxygen species. This experiment was planned to evaluate the protective effect of thymoquinone against subchronic ethanol toxicity in rats. Materials and Methods: Experiments were performed on six groups. Each group consisted of six animals, including control group (saline, gavage), ethanol-receiving group (3 g/kg/day, gavage), thymoquinone (2.5, 5, 10 mg/Kg/day, intraperitoneally (IP)) plus ethanol and thymoquinone (10 mg/Kg/day, IP) groups. Treatments were carried out in four weeks. Results: Thymoquinone reduced the ethanol-induced increase in the lipid peroxidation and severity of histopathological alteration in liver and kidney tissues. In addition it improved the levels of proinflammatory cytokines in liver tissue. Furthermore, thymoquinone corrected the liver enzymes level including alanine transaminase, aspartate transaminase and alkaline phosphatase in serum and glutathione content in liver and kidney tissues. Other experiments such as Western blot analysis and quantitative real-time RT-PCR revealed that thymoquinone suppressed the expression of Bax/Bcl-2 ratio (both protein and mRNA level), and caspases activation pursuant to ethanol toxicity. Conclusion: This study indicates that thymoquinone may have preventive effects against ethanol toxicity in the liver and kidney tissue through reduction in lipid peroxidation and inflammation, and also interrupting apoptosis

Targeted delivery of doxorubicin and therapeutic FOXM1 aptamer to tumor cells using gold nanoparticles modified with AS1411 and ATP aptamers

Objective(s): A targeted delivery platform was prepared to co-deliver both doxorubicin (Dox) as an anticancer drug and FOXM1 aptamer as a therapeutic substance to breast cancer cells (4T1 and MCF-7) to reduce Dox side effects and increase its therapeutic efficacy. The targeted system (AuNPs-AFPA) consisted of FOXM1 aptamer, AS1411 aptamer (targeting oligonucleotide), ATP aptamer, and gold nanoparticles (AuNPs) as a carrier.Materials and Methods: AuNPs were synthesized by reduction of HAuCl4. Next, after pegylation of ATP aptamer, FOXM1 aptamer-PEGylated ATP aptamer conjugate (FPA) was prepared. Then, the AS1411 aptamer and FPA were exposed to the AuNPs surface through their thiol groups. Subsequently, Dox was loaded into the complex to form a targeted therapeutic complex.Results: The data of the MTT assay displayed that the targeted complex could remarkably reduce cell viability rate in target cells due to the overexpression of nucleolin on their cell membranes compared to nontarget cells, showing the targeting ability of AuNPs-AFPA-Dox. The in vivo antitumor effect confirmed that AuNPs-AFPA-Dox was capable of remarkably diminishing tumor growth relative to the free Dox in mice bearing 4T1 tumor cells. Conclusion: The results confirmed that the targeted system improved the therapeutic effect by loading high amounts of Dox alongside the presence of the therapeutic effect of FOXM1 aptamer. Finally, it can be concluded that AuNPs-AFPA-Dox by enhancing antitumor effectiveness and reducing toxicity toward non-target cells, can be used potentially as an effective strategy for the treatment of breast cancer.

Inhibition of Akt phosphorylation attenuates resistance to TNF-α cytotoxic effects in MCF-7 cells, but not in their doxorubicin resistant derivatives

Objective(s): Acquisition of TNF-α resistance plays role in the onset and growth of malignant tumors. Previous studies have demonstrated that MCF-7 cell line and its doxorubicin resistant variant MCF-7/Adr are resistant against the cytotoxic effects of TNF-α. In this study, we investigated the role of Akt activation in resistance of MCF-7 and MCF-7/Adr against TNF-α cytotoxicity. Materials and Methods: The role of Akt activation in TNF-α cytotoxicity was investigated by MTT cell viability assay following treatment of the cells with the chemical inhibitor of Akt activation with or without TNF-α treatment. Phosphorylation of Akt at Ser473 before and after 72 hr TNF-α treatment  was also determined by western blot. Results: TNF-α treatment led to enhancement of Akt Ser473 phosphorylation. Treatment of MCF-7 cells with TNF-α along with Akt-inhibitor agent, tricribine, attenuated Akt Ser473 phosphorylation and sensitized these cells to the cytotoxic effects of TNF-α in a dose and time dependent manner while tricribine treatment did not cause any significant cytotoxicity in MCF-7/Adr cells alone or in combination with TNF-α. Conclusion: These results demonstrate that Akt phosphorylation plays pivotal role in the resistance of MCF-7 cells against TNF-α-induced cytotoxicity while it might play no significant role in the resistance of MCF-7/Adr cells against TNF-α

Comparative proteome analysis of human esophageal cancer and adjacent normal tissues

Objective(s): Ranking as the sixth commonest cancer, esophageal squamous cell carcinoma (ESCC) represents one of the leading causes of cancer death worldwide. One of the main reasons for the low survival of patients with esophageal cancer is its late diagnosis. Materials and Methods: We used proteomics approach to analyze ESCC tissues with the aim of a better understanding of the malignant mechanism and searching candidate protein biomarkers for early diagnosis of esophageal cancer. The differential protein expression between cancerous               and normal esophageal tissues was investigated by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). Then proteins were identified by matrix-assisted laser desorption/ ionization tandem time-of-flight mass spectrometry (MALDI-TOF/TOF-MS) and MASCOT web based search engine. Results:We reported 4 differentially expressed proteins involved in the pathological process of esophageal cancer, such as annexinA1 (ANXA1), peroxiredoxin-2 (PRDX2), transgelin (TAGLN) andactin-aortic smooth muscle (ACTA2). Conclusion: In this report we have introduced new potential biomarker (ACTA2). Moreover, our data confirmed some already known markers for EC in our region

Regulation of skeletal muscle creatine kinase from a hibernating mammal

Control over skeletal muscle energetics is critical in hibernation to sustain viability over weeks of cold torpor and to support shivering thermogenesis during arousal. Creatine kinase (CK)1Abbreviations used: CK, creatine kinase; Cr, creatine; PCr, phosphocreatine; PKC, protein kinase C.1 has a key role in muscle energetics and this study analyzes muscle CK from ground squirrels, Spermophilus richardsonii. CK activity was ∼20% lower during hibernation than in euthermia, as was CK protein whereas CK mRNA was reduced by ∼70%. Hibernator CK showed reduced affinity for ATP and creatine, compared with euthermic CK. Incubations that promoted endogenous protein kinase or phosphatase action, coupled with ion exchange chromatography to separate high and low phosphate forms, showed that soluble CK from euthermic squirrels was a mix of phosphorylated and dephosphorylated forms whereas only phospho-CK was detected in hibernating animals. High and low phosphate CK forms had different affinities for ATP and creatine substrates but did not differ in stability to urea denaturation. About 20-25% of CK was bound to the insoluble fraction of muscle and bound CK showed different kinetic responses to kinase and phosphatase treatments