N-n-butyl haloperidol iodide mediates cardioprotection via regulating AMPK/FoxO1 signalling.

Derangement of redox condition largely contributes to cardiac ischemia/reperfusion (I/R) injury. FoxO1 is a transcription factor which transcripts a series of antioxidants to antagonize I/R-induced oxidative myocardial damage. N-n-butyl haloperidol iodide (F2 ) is a derivative derived from haloperidol structural modification with potent capacity of inhibiting oxidative stress. This investigation intends to validate whether cardio-protection of F2 is dependent on FoxO1 using an in vivo mouse I/R model and if so, to further elucidate the molecular regulating mechanism. This study initially revealed that F2 preconditioning led to a profound reduction in I/R injury, which was accompanied by attenuated oxidative stress and upregulation of antioxidants (SOD2 and catalase), nuclear FoxO1 and phosphorylation of AMPK. Furthermore, inactivation of FoxO1 with AS1842856 abolished the cardio-protective effect of F2 . Importantly, we identified F2 -mediated nuclear accumulation of FoxO1 is dependent on AMPK, as blockage of AMPK with compound C induced nuclear exit of FoxO1. Collectively, our data uncover that F2 pretreatment exerts significant protection against post ischemic myocardial injury by its regulation of AMPK/FoxO1 pathway, which may provide a new avenue for treating ischemic disease.

The Common LncRNAs of Neuroinflammation-Related Diseases.

Spatio-temporal specific long noncoding RNAs (lncRNAs) play important regulatory roles not only in the growth and development of the brain but also in the occurrence and development of neurologic diseases. Generally, the occurrence of neurologic diseases is accompanied by neuroinflammation. Elucidation of the regulatory mechanisms of lncRNAs on neuroinflammation is helpful for the clinical treatment of neurologic diseases. This paper focuses on recent findings on the regulatory effect of lncRNAs on neuroinflammatory diseases and selects 10 lncRNAs that have been intensively studied to analyze their mechanism action. The clinical treatment status of lncRNAs as drug targets is also reviewed. SIGNIFICANCE STATEMENT: Gene therapies such as clustered regularly interspaced short palindrome repeats technology, antisense RNA technology, and RNAi technology are gradually applied in clinical treatment, and the development of technology is based on a large number of basic research investigations. This paper focuses on the mechanisms of lncRNAs regulation of neuroinflammation, elucidates the beneficial or harmful effects of lncRNAs in neurosystemic diseases, and provides theoretical bases for lncRNAs as drug targets.

Helix B Surface Peptide Protects Cardiomyocytes From Hypoxia/Reoxygenation-induced Autophagy Through the PI3K/Akt Pathway.

BACKGROUND: Helix B surface peptide (HBSP) is a newly discovered tissue-protective erythropoietin derivative that provides benefits after myocardial ischemia/reperfusion. This study explores the cardioprotective effects of HBSP in myocardial cells in response to hypoxia/reoxygenation injury and its potential mechanism. METHODS: In this study, rat ventricular (H9c2) cell cultures were established and pretreated with HBSP. H9c2 cardiomyocytes were randomly assigned to the control, H/R, H/R + LY294002 (a PI3K inhibitor), HBSP + H/R, and HBSP + H/R + LY294002 groups. The pretreated cardiomyocytes underwent H/R, and the cardiomyocytes were monitored for viability through a CCK-8 assay, whereas flow cytometry was used to test cell apoptosis. Orgotein Superoxide Dismutase (SOD) and lactate dehydrogenase (LDH) expression were monitored by SOD and LDH kits, respectively. The expression of LC3 autophagosomes was determined by immunocytochemistry. The expression of LC3II/LC3I, p-Mammalian Target of Rapamycin (mTOR) mTOR, mTOR, Beclin 1, p-PI3K, PI3K p-Akt, and Akt was determined by Western blotting. RESULTS: HBSP increased cell viability and reduced SOD and LDH production, and it also reduced H/R-induced cell apoptosis. Moreover, the expression of the autophagy-related proteins (LC3II/LC3I) was inhibited by HBSP, whereas the expression of p-PI3K, p-Akt, and p-mTOR was enhanced. However, the PI3K inhibitor (LY294002) notably abolished these effects in H9c2 cells. CONCLUSIONS: HBSP inhibits excessive autophagy and apoptosis induced by H/R by activating the PI3K/Akt pathway. HBSP may potentially be a therapeutic intervention for myocardial ischemia/reperfusion injury.

Evaluation of reference genes for gene expression studies in mouse and N2a cell ischemic stroke models using quantitative real-time PCR.

BACKGROUND: Real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR) is a critical tool for evaluating the levels of mRNA transcribed from genes. Reliable RT-qPCR results largely depend on normalization to suitable reference genes. Middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation/reoxygenation (OGD/R) are models that are commonly used to study ischemic stroke. However, the proper reference genes for RNA analysis in these two models have not yet been determined. RESULTS: In this study, we evaluated the expression levels of six candidate housekeeping genes and selected the most suitable reference genes for RT-qPCR analyses of the cortices of MCAO mice and OGD/R-injured N2a cells. Four software programs, geNorm, NormFinder, BestKeeper and RefFinder, were used to validate the stabilities of the candidate reference genes. The results revealed that HPRT and 18S were the most stable reference genes in the cortices of MCAO mice and that ß-actin and cyclophilin were the most stable reference genes in the OGD/R-injured N2a cells; in contrast, GAPDH and Sdha were the least stable genes in the cortices of MCAO mice and the OGD/R-injured N2a cells, respectively. Moreover, a combination of HPRT, 18S and cyclophilin was most suitable for normalization in analyses of the cortices of MCAO mice, and a combination of ß-actin, cyclophilin, GAPDH, and 18S was most suitable for analyses of the OGD/R-injured N2a cells. CONCLUSIONS: This study provides appropriate reference genes for further RT-qPCR analyses of in vivo and in vitro ischemic stroke and demonstrates the necessity of validating reference genes for RNA analyses under variable conditions.

Protective effect of Gelofusine against cRGD-siRNA-induced nephrotoxicity in mice.

Based on successful targeting to the αvß3 integrin of cyclic arginine-glycine-aspartic acid (cRGD), cRGD-conjugated small interfering RNA (siRNA) exhibits tumor targeting and has become a new treatment strategy for solid tumors. However, the nephrotoxicity caused by its renal retention limits its clinical application. Here, we evaluated the protective effect of Gelofusine against cRGD-conjugated siRNA-induced nephrotoxicity in mice. Male Kunming mice (six per group) were either co-injected with Gelofusine and cRGD-siRNA or injected with cRGD-siRNA alone. After administration of these treatments five times, creatinine and blood urea nitrogen (BUN) levels were determined. Hematoxylin-eosin staining (HE staining) and transferase dUTP nick end labeling (TUNEL) analysis were used to compare the difference in renal damage between the groups. Additionally, fluorescence imaging was used to observe the distribution of cRGD-siRNA in vivo. The group co-injected with Gelofusine and cRGD-siRNA displayed lower creatinine and BUN levels than the cRGD-siRNA-alone group and showed less renal damage upon HE staining and TUNEL analysis. Gelofusine decreased the retention time and accelerated the elimination of cRGD-siRNA from the organs, as observed in the fluorescence images. These data indicate that Gelofusine significantly increased the excretion of cRGD-conjugated siRNA and reduced the associated renal damage.

Tumor-targeted in vivo gene silencing via systemic delivery of cRGD-conjugated siRNA.

RNAi technology is taking strong position among the key therapeutic modalities, with dozens of siRNA-based programs entering and successfully progressing through clinical stages of drug development. To further explore potentials of RNAi technology as therapeutics, we engineered and tested VEGFR2 siRNA molecules specifically targeted to tumors through covalently conjugated cyclo(Arg-Gly-Asp-d-Phe-Lys[PEG-MAL]) (cRGD) peptide, known to bind αvß3 integrin receptors. cRGD-siRNAs were demonstrated to specifically enter and silence targeted genes in cultured αvß3 positive human cells (HUVEC). Microinjection of zebrafish blastocysts with VEGFR2 cRGD-siRNA resulted in specific inhibition of blood vessel growth. In tumor-bearing mice, intravenously injected cRGD-siRNA molecules generated no innate immune response and bio-distributed to tumor tissues. Continuous systemic delivery of two different VEGFR2 cRGD-siRNAs resulted in down-regulation of corresponding mRNA (55 and 45%) and protein (65 and 45%) in tumors, as well as in overall reduction of tumor volume (90 and 70%). These findings demonstrate strong potential of cRGD-siRNA molecules as anti-tumor therapy.

Regulation of lncRNA expression.

Long non-coding RNAs (lncRNAs) are series of transcripts with important biological functions. Various diseases have been associated with aberrant expression of lncRNAs and the related dysregulation of mRNAs. In this review, we highlight the mechanisms of dynamic lncRNA expression. The chromatin state contributes to the low and specific expression of lncRNAs. The transcription of non-coding RNA genes is regulated by many core transcription factors applied to protein-coding genes. However, specific DNA sequences may allow their unsynchronized transcription with their location-associated mRNAs. Additionally, there are multiple mechanisms involved in the post-transcriptional regulation of lncRNAs. Among these, microRNAs might have indispensible regulatory effects on lncRNAs, based on recent discoveries.

Cost-effectiveness of CYP2C19 genotyping to guide antiplatelet therapy for acute minor stroke and high-risk transient ischemic attack.

Dual antiplatelet therapy (DAPT) with clopidogrel plus aspirin within 48 h of acute minor strokes and transient ischemic attacks (TIAs) has been indicated to effectively reduce the rate of recurrent strokes. However, the efficacy of clopidogrel has been shown to be affected by cytochrome P450 2C19 (CYP2C19) polymorphisms. Patients carrying loss-of-function alleles (LoFAs) at a low risk of recurrence (ESRS < 3) cannot benefit from clopidogrel plus aspirin at all and may have an increased bleeding risk. In order to optimize antiplatelet therapy for these patients and avoid the waste of medical resources, it is important to identify the subgroups that genuinely benefit from DAPT with clopidogrel plus aspirin through CYP2C19 genotyping. This study sought to assess the cost-effectiveness of CYP2C19 genotyping to guide drug therapy for acute minor strokes or high-risk TIAs in China. A decision tree and Markov model were constructed to evaluate the cost-effectiveness of CYP2C19 genotyping. We used a healthcare payer perspective, and the primary outcomes included quality-adjusted life years (QALYs), costs and the incremental cost-effectiveness ratio (ICER). Sensitivity analyses were performed to evaluate the robustness of the results. CYP2C19 genotyping resulted in a lifetime gain of 0.031 QALYs at an additional cost of CNY 420.13 (US$ 59.85), yielding an ICER of CNY 13,552.74 (US$ 1930.59) per QALY gained. Probabilistic sensitivity analysis showed that genetic testing was more cost-effective in 95.7% of the simulations at the willingness-to-pay threshold of CNY 72,100 (GDP per capita, US$ 10,300) per QALY. Therefore, CYP2C19 genotyping to guide antiplatelet therapy for acute minor strokes and high-risk TIAs is highly cost-effective in China.

Erythropoietin helix B surface peptide modulates miR-21/Atg12 axis to alleviates cardiomyocyte hypoxia-reoxygenation injury.

BACKGROUND: The erythropoietin helix B surface peptide (HBSP) has been shown to have neuroprotective and repair-damaging myocardium effects similar to erythropoietin (EPO). However, the protective mechanism of HBSP on cardiomyocyte hypoxia-reoxygenation (H/R) injury is not clear. METHODS: H9C2 cells were pretreated with HBSP and subjected to hypoxia/reoxygenation (H/R), changes in cell function, autophagy and apoptosis were assessed, respectively. Cells were transfected with miR-21 mimic and miR-NC, and the relative expression of miR-21 and Atg12 were detected by qRT-PCR. The target role of miR-21 and Atg12 was evaluated by dual-luciferase reporter. After transfected with si-Atg12 and si-NC, western blot was used to assess autophagy and apoptosis proteins, flow cytometry assay was used to detect apoptosis rate. RESULTS: We found the expression of miR-21 was significantly down-regulated, accompanied by remarkably activated of autophagy and apoptosis in H9C2 cells during H/R injury. Pleasantly, HBSP pretreatment has a similar effect as transfection of miR-21 mimic, which is to evidently inhibit autophagy and apoptosis by up-regulating miR-21 expression. Moreover, Bioinformatics analysis and luciferase reporter assay revealed that Atg12 was directly bond to miR-21. To further understand whether Atg12 is involved in the process of miR-21 regulating autophagy, si-Atg12 and si-NC were transfected into H9C2 cell, the results showed that knockdown of Atg12 enhances the inhibition autophagy and apoptosis effect of HBSP. CONCLUSION: These results demonstrate that HBSP inhibits myocardial H/R injury induced by autophagy over-activation and apoptosis via miR-21/Atg12 axis.

A tumor-targeting cRGD-EGFR siRNA conjugate and its anti-tumor effect on glioblastoma in vitro and in vivo.

The epidermal growth factor receptor (EGFR) is an important anti-tumor target. The development of novel molecular-targeted anti-tumor drugs that can target the interior of tumor cells and specifically silence EGFR expression is valuable and promising. In this work, a promising anti-tumor conjugate comprising methoxy-modified EGFR siRNA and cyclic arginine-glycine-aspartic acid (cRGD) peptides, which selectively bind to αvß3 integrins, was synthesized and examined. To prepare cRGD-EGFR siRNA (cRGD-siEGFR), cRGD was covalently conjugated to the 5'-end of an siRNA sense strand using a thiol-maleimide linker. The cellular uptake and cytotoxicity of cRGD-siEGFR in vitro were tested using an αvß3-positive U87MG cell line. In vivo bio-distribution, anti-tumor activity, immunogenicity and toxicity were investigated in a nude mouse tumor model through repeated i.v. administration of cRGD-siEGFR (7 times over a 48 h interval). Analyses of in vitro data showed that cRGD-siEGFR silenced EGFR expression effectively, with high tumor targeting ability. Administration of cRGD-siEGFR to tumor-bearing nude mice led to significant inhibition of tumor growth, obvious reduction of EGFR expression and down-regulation of EGFR mRNA and protein in tumor tissue. Furthermore, serum biochemistry and pathological section evaluation did not indicate any serious toxicity of cRGD-siEGFR in vivo. cRGD-siEGFR is likely a promising candidate with high targeting ability, substantial anti-tumor effects and low toxicity in vitro and in vivo.

LncRNA-N1LR Enhances Neuroprotection Against Ischemic Stroke Probably by Inhibiting p53 Phosphorylation.

In recent years, long noncoding RNAs (lncRNAs) have been shown to have critical roles in a broad range of cell biological processes. However, the activities of lncRNAs during ischemic stroke remain largely unknown. In this study, we carried out a genome-wide lncRNA microarray analysis in rat brains with ischemia/reperfusion (I/R) injury. The results revealed the differential expression of a subset of lncRNAs. Through the construction of lncRNA-mRNA co-expression networks, we identified lncRNA-N1LR as a novel I/R-induced lncRNA. The functions of lncRNA-N1LR were assessed by silencing and overexpressing this lncRNA in vitro and in vivo. We found that lncRNA-N1LR enhanced cell cycle progression and cell proliferation, and inhibited apoptosis in N2a cells subjected to in vitro ischemia (oxygen-glucose deprivation/reoxygenation, OGD/R). Furthermore, we showed that lncRNA-N1LR reduced neuronal apoptosis and neural cell loss in I/R-induced mouse brains. Mechanistically, we discovered that lncRNA-N1LR promoted neuroprotection probably through the inhibition of p53 phosphorylation on serine 15 in a manner that was independent of its location-associated gene Nck1. In summary, our results indicated that lncRNA-N1LR promoted neuroprotection against ischemic stroke probably by inactivating p53. Thus, we propose that lncRNA-N1LR may serve as a potential target for therapeutic intervention following ischemic brain injury.

[Effects of serum starvation on cell cycle synchronization in primary human umbilical vein endothelial cells].

OBJECTIVE: To investigate the optimal starvation conditions of human umbilical vein endothelial cells (HUVECs) and establish a highly efficient and stable method for separating HUVECs. METHODS: HUVECs harvested from human umbilical cords by digestion with 0.1% collagenase II for 15 min were cultured in endothelial culture medium (ECM) containing 5% fetal bovine serum (FBS), 1% endothelial cell growth factor (ECGS) and 1% penicillin/streptomycin solution(P/S) at 37 degrees celsius; in 5% CO2. The cells were observed for cell morphology under an inverted microscope and identified with immunofluorescence assay. The purity of HUVECs was detected using flow cytometry (FCM). The cell cycles of HUVECs cultured in the presence of 0, 0.1%, 0.5%, and 1% FBS for 0, 6, 12, 18, and 24 h were analyzed with flow cytometry. RESULTS: s The purity of HUVECs harvested by digestion with 0.1% collagenase II reached 99.67%. The primary HUVECs showed a cobblestone or volute appearance in vitro. Immunocytochemistry showed that HUVECs highly expressed VIII-related antigen. Cell culture in the presence of different concentrations of FBS for 6 h resulted in 70% G0/G1 phase cells, which increased to 80%-90% at 12 h of cell culture, and further to around 95% at 18 and 24 h. CONCLUSION: Digestion with 0.1% collagenase II can obtain high-purity primary HUVECs. Culturing HUVECs in serum-free medium for 12 h can result in a high purity (over 80%) of G0/G1 phase cells.

Evaluation of melanoma antigen gene A3 expression in drug resistance of epidermal growth factor receptor-tyrosine kinase inhibitors in advanced nonsmall cell lung cancer treatment.

OBJECTIVE: To investigate the correlation between melanoma antigen gene A3 (MAGE-A3) expression and progression-free survival (PFS) of nonsmall cell lung cancer (NSCLC) patients with epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKIs) therapy, aiming to provide a basis for research and treatment of EGFR-TKIs resistance. RESEARCH AND METHODS: Retrospective analysis is conducted of PFS of 359 NSCLC patients who have been tested positive for EGFR, and experienced drug resistance during oral treatment of icotinib. MAGE-A3 expression is tested using immunology and histology chemistry methods, and T790M and c-MeT expression are tested using mutation-enriched polymerase chain reaction. RESULTS: (1) MAGE-A3 expression in targeted treatment of NSCLC patients shows a positive rate of 33.98%. The comparative difference between MAGE-A3 expression and T790M, c-MeT and other resistance genes was not statistically significant (P > 0.05). (2) MAGE-A3 expression was higher in patients with NSCLC targeted therapy of primary drug resistance of positive rate than acquired resistance; meanwhile the expression level differences in three modes of acquired resistance are statistically significant (P < 0.05). (3) PFS of MAGE-A3 positive expression in the targeted treatment of acquired drug resistance in patients with NSCLC is shorter than the PFS of MAGE-A3 negative expression (P = 0.01); the comparative PFS differences in the three kinds of acquired drug resistance pattern have statistical significance (P = 0.02). (4) PFS and levels of MAGE-A3 expression in NSCLC patients with the three modes of acquired resistance are negatively correlated (P < 0.01), and MAGE-A3 expression has no correlation with age, gender, pathological type or PS score (P > 0.05). CONCLUSION: MAGE-A3 expression in EGFR-TKIs target therapy in NSCLC patient suggests that there might be EGFR-TKIs drug resistance, and the higher the level of expression, the shorter the time of acquired drug resistance.

Α­lipoic acid protects against cerebral ischemia/reperfusion-induced injury in rats.

It is well established that the brain is sensitive to ischemia/reperfusion (I/R)­induced injury. α­lipoic acid (LA), a free radical scavenger and antioxidant, has a neuroprotective effect against cerebral I/R­induced injury, however, the underlying mechanisms remain to be elucidated. Therefore, the present study was undertaken to evaluate whether LA was able to protect against cerebral I/R­induced injury and to examine the potential mechanisms. The neuroprotective effects of LA were investigated in a rat model of transient focal ischemia induced by middle cerebral artery occlusion (MCAO) followed by reperfusion. Adult male Sprague­Dawley rats were randomly assigned into the sham, cerebral I/R injury model and model plus LA groups. Cerebral I/R injury was induced by 90 min MCAO followed by reperfusion for 24 h. Cerebral infarct size was detected by 2,3,5­triphenyltetrazolium chloride staining. Neurological deficit score (NDS), brain water content and oxidative parameters, including malondialdehyde (MDA), nitric oxide (NO), total antioxidant capacity (T­AOC) and superoxide dismutase (SOD) were measured. The expression of cleaved caspase­3, brain­derived neurotrophic factor (BDNF), phosphatidylinositol­4,5­bisphosphate 3­kinase (PI3K), p­Akt and phosphorylated extracellular signal­regulated kinase 1/2 (p­ERK1/2) were also analyzed using western blotting. The present study demonstrated that pretreatment with LA significantly decreased the infarction size, brain water content and improved NDS. LA reversed the levels of oxidative parameters, including MDA, NO, T­AOC and SOD to their normal state in rat brains following cerebral I/R. Furthermore, the expression of cleaved caspase­3 markedly decreased and the expression of BDNF, PI3K, p­Akt and p­ERK1/2 significantly increased following administration of LA. On the basis of these findings, it was concluded that LA protected the brain from cerebral I/R damage by attenuation of oxidative stress and caspase­dependent apoptosis. Furthermore, LA exerts its neuroprotective effects potentially through activation of the BDNF­PI3K/Akt­ERK1/2 pathway.

α-Lipoic acid protects against hypoxia/reoxygenation-induced injury in human umbilical vein endothelial cells through suppression of apoptosis and autophagy.

α-Lipoic acid (ALA) is known as a powerful antioxidant, which has been reported to have protective effects against various cardiovascular diseases. The present study aimed to determine whether ALA pre- or post-treatment induced protective effects against hypoxia/reoxygenation-induced injury via inhibition of apoptosis and autophagy in human umbilical vein endothelial cells (HUVECs). In order to simulate the conditions of hypoxia/reoxygenation, HUVECs were subjected to 4 h of oxygen-glucose deprivation (OGD) followed by 12 h of reoxygenation. For the pre-treatment, ALA was added to the buffer 12 h prior to OGD, whereas for the post-treatment, ALA was added at the initiation of reoxygenation. The results demonstrated that ALA pre- or post-treatment significantly reduced lactate dehydrogenase (LDH) release induced through hypoxia/reoxygenation in HUVECs in a dose-dependent manner; of note, 1 mM ALA pre- or post-treatment exhibited the most potent protective effects. In addition, ALA significantly reduced hypoxia/reoxygenation-induced loss of mitochondrial membrane potential, apoptosis and the expression of cleaved caspase-3 in HUVECs. In the presence of the specific autophagy inhibitor 3-methyladenine, hypoxia/reoxygenation-induced apoptosis was significantly reduced. Furthermore, the formation of autophagosomes, cytosolic microtubule-associated protein 1A/1B-light chain 3 ratio and beclin1 levels significantly increased following hypoxia/reoxygenation injury; however, all of these effects were ameliorated following pre- or post-treatment with ALA. The results of the present study suggested that ALA may provide beneficial protection against hypoxia/reoxygenation-induced injury via attenuation of apoptosis and autophagy in HUVECs.

Meta-analysis of methylcobalamin alone and in combination with prostaglandin E1 in the treatment of diabetic peripheral neuropathy.

This study aimed to compare the efficacy and safety of prostaglandin E1 plus methylcobalamin (PGE1-MC) with that of methylcobalamin alone (MC) on diabetic peripheral neuropathy (DPN). We searched published randomized controlled trials (RCTs) of PGE1 combined with MC for DPN up to June 1, 2013. Data were extracted to evaluate methodological quality and describe characteristics of studies in duplicate. A random or a fixed effect model was used to analyze outcomes which were expressed as relative risk (RR) or mean difference with a 95 % confidence interval (CI). All data were analyzed using Review Manager 5.2 software. Twenty-six RCTs involving 2,107 individuals were included. Meta-analysis showed that PGE1-MC combination therapy was significantly better than MC monotherapy (RR = 1.40; 95 % CI 1.33-1.48) on efficacy. The weighted mean differences in nerve conduction velocities (NCVs) were 6.72 (95 % CI: 5.42-8.02) for median motor nerve conduction velocity (MNCV), 5.13 (CI 4.13-6.13) for median sensory nerve conduction velocity (SNCV), 5.74 (CI 4.87-6.61) for peroneal MNCV and 4.62 (CI 3.89-5.34) for peroneal SNCV in favor of the PGE1 + MC combination group. Moreover, there were no serious adverse events in both groups during the treatment period. The results of the meta-analysis show that treatment with PGE1-MC is safe and can gain better outcomes in neuropathic symptoms and NCVs compared with MC alone. However, the conclusion may not be strong because most of the studies included in this meta-analysis have poor methodological quality.

Something between the amazing functions and various morphologies of self-assembling peptides materials in the medical field.

In recent years, there are a growing number of researches in the field of self-assembling peptides. Due to their diversity structures and the promising applications, self-assembling peptides have already become the focus of studies in the fields of materials and biological science. Some amazing functions of these peptides in the medical field caught our attention, such as tissue repair and regeneration, therapeutic delivery, haemostasis, antimicrobial and so on. There are different morphologies of self-assembling peptides in different functions. This review provides an overview of the relationship between some amazing functions and various morphologies of self-assembling peptides principally. Furthermore, the mechanisms of peptide self-assembly are also discussed.

Self-assembled nanoparticles based on the c(RGDfk) peptide for the delivery of siRNA targeting the VEGFR2 gene for tumor therapy.

The clinical application of small interfering RNA (siRNA) has been restricted by their poor intracellular uptake, low serum stability, and inability to target specific cells. During the last several decades, a great deal of effort has been devoted to exploring materials for siRNA delivery. In this study, biodegradable, tumor-targeted, self-assembled peptide nanoparticles consisting of cyclo(Arg-Gly-Asp-d-Phe-Lys)-8-amino-3,6-dioxaoctanoic acid-ß-maleimidopropionic acid (hereafter referred to as RPM) were found to be an effective siRNA carrier both in vitro and in vivo. The nanoparticles were characterized based on transmission electron microscopy, circular dichroism spectra, and dynamic light scattering. In vitro analyses showed that the RPM/VEGFR2-siRNA exhibited negligible cytotoxicity and induced effective gene silencing. Delivery of the RPM/VEGFR2 (zebrafish)-siRNA into zebrafish embryos resulted in inhibition of neovascularization. Administration of RPM/VEGFR2 (mouse)-siRNA to tumor-bearing nude mice led to a significant inhibition of tumor growth, a marked reduction of vessels, and a down-regulation of VEGFR2 (messenger RNA and protein) in tumor tissue. Furthermore, the levels of IFN-α, IFN-γ, IL-12, and IL-6 in mouse serum, assayed via enzyme-linked immunosorbent assay, did not indicate any immunogenicity of the RPM/VEGFR2 (mouse)-siRNA in vivo. In conclusion, RPM may provide a safe and effective delivery vector for the clinical application of siRNAs in tumor therapy.